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38f8b050 | 1 | /* Target hook definitions. |
7adcbafe | 2 | Copyright (C) 2001-2022 Free Software Foundation, Inc. |
38f8b050 JR |
3 | |
4 | This program is free software; you can redistribute it and/or modify it | |
5 | under the terms of the GNU General Public License as published by the | |
6 | Free Software Foundation; either version 3, or (at your option) any | |
7 | later version. | |
8 | ||
9 | This program is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | GNU General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU General Public License | |
15 | along with this program; see the file COPYING3. If not see | |
16 | <http://www.gnu.org/licenses/>. | |
17 | ||
18 | In other words, you are welcome to use, share and improve this program. | |
19 | You are forbidden to forbid anyone else to use, share and improve | |
20 | what you give them. Help stamp out software-hoarding! */ | |
21 | ||
acce4e77 JM |
22 | /* See target-hooks-macros.h for details of macros that should be |
23 | provided by the including file, and how to use them here. */ | |
24 | #include "target-hooks-macros.h" | |
38f8b050 | 25 | |
acce4e77 JM |
26 | #undef HOOK_TYPE |
27 | #define HOOK_TYPE "Target Hook" | |
38f8b050 | 28 | |
acce4e77 | 29 | HOOK_VECTOR (TARGET_INITIALIZER, gcc_target) |
38f8b050 JR |
30 | |
31 | /* Functions that output assembler for the target. */ | |
32 | #define HOOK_PREFIX "TARGET_ASM_" | |
33 | HOOK_VECTOR (TARGET_ASM_OUT, asm_out) | |
34 | ||
35 | /* Opening and closing parentheses for asm expression grouping. */ | |
36 | DEFHOOKPOD | |
37 | (open_paren, | |
673c2f63 JM |
38 | "These target hooks are C string constants, describing the syntax in the\n\ |
39 | assembler for grouping arithmetic expressions. If not overridden, they\n\ | |
40 | default to normal parentheses, which is correct for most assemblers.", | |
38f8b050 JR |
41 | const char *, "(") |
42 | DEFHOOKPODX (close_paren, const char *, ")") | |
43 | ||
44 | /* Assembler instructions for creating various kinds of integer object. */ | |
45 | DEFHOOKPOD | |
46 | (byte_op, | |
673c2f63 | 47 | "@deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_HI_OP\n\ |
cac6691c | 48 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_PSI_OP\n\ |
673c2f63 | 49 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_SI_OP\n\ |
cac6691c | 50 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_PDI_OP\n\ |
673c2f63 | 51 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_DI_OP\n\ |
cac6691c | 52 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_PTI_OP\n\ |
673c2f63 JM |
53 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_ALIGNED_TI_OP\n\ |
54 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_HI_OP\n\ | |
cac6691c | 55 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_PSI_OP\n\ |
673c2f63 | 56 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_SI_OP\n\ |
cac6691c | 57 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_PDI_OP\n\ |
673c2f63 | 58 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_DI_OP\n\ |
cac6691c | 59 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_PTI_OP\n\ |
673c2f63 JM |
60 | @deftypevrx {Target Hook} {const char *} TARGET_ASM_UNALIGNED_TI_OP\n\ |
61 | These hooks specify assembly directives for creating certain kinds\n\ | |
62 | of integer object. The @code{TARGET_ASM_BYTE_OP} directive creates a\n\ | |
63 | byte-sized object, the @code{TARGET_ASM_ALIGNED_HI_OP} one creates an\n\ | |
64 | aligned two-byte object, and so on. Any of the hooks may be\n\ | |
65 | @code{NULL}, indicating that no suitable directive is available.\n\ | |
66 | \n\ | |
67 | The compiler will print these strings at the start of a new line,\n\ | |
68 | followed immediately by the object's initial value. In most cases,\n\ | |
69 | the string should contain a tab, a pseudo-op, and then another tab.", | |
38f8b050 JR |
70 | const char *, "\t.byte\t") |
71 | DEFHOOKPOD (aligned_op, "*", struct asm_int_op, TARGET_ASM_ALIGNED_INT_OP) | |
72 | DEFHOOKPOD (unaligned_op, "*", struct asm_int_op, TARGET_ASM_UNALIGNED_INT_OP) | |
73 | ||
74 | /* Try to output the assembler code for an integer object whose | |
75 | value is given by X. SIZE is the size of the object in bytes and | |
76 | ALIGNED_P indicates whether it is aligned. Return true if | |
77 | successful. Only handles cases for which BYTE_OP, ALIGNED_OP | |
78 | and UNALIGNED_OP are NULL. */ | |
79 | DEFHOOK | |
80 | (integer, | |
673c2f63 JM |
81 | "The @code{assemble_integer} function uses this hook to output an\n\ |
82 | integer object. @var{x} is the object's value, @var{size} is its size\n\ | |
83 | in bytes and @var{aligned_p} indicates whether it is aligned. The\n\ | |
84 | function should return @code{true} if it was able to output the\n\ | |
85 | object. If it returns false, @code{assemble_integer} will try to\n\ | |
86 | split the object into smaller parts.\n\ | |
87 | \n\ | |
88 | The default implementation of this hook will use the\n\ | |
89 | @code{TARGET_ASM_BYTE_OP} family of strings, returning @code{false}\n\ | |
90 | when the relevant string is @code{NULL}.", | |
38f8b050 JR |
91 | /* Only handles cases for which BYTE_OP, ALIGNED_OP and UNALIGNED_OP are |
92 | NULL. */ | |
93 | bool, (rtx x, unsigned int size, int aligned_p), | |
94 | default_assemble_integer) | |
95 | ||
dddb7af4 ST |
96 | /* Assembly strings required after the .cfi_startproc label. */ |
97 | DEFHOOK | |
98 | (post_cfi_startproc, | |
99 | "This target hook is used to emit assembly strings required by the target\n\ | |
100 | after the .cfi_startproc directive. The first argument is the file stream to\n\ | |
7e1f39b6 JL |
101 | write the strings to and the second argument is the function\'s declaration. The\n\ |
102 | expected use is to add more .cfi_* directives.\n\ | |
dddb7af4 ST |
103 | \n\ |
104 | The default is to not output any assembly strings.", | |
105 | void, (FILE *, tree), | |
106 | hook_void_FILEptr_tree) | |
107 | ||
dc2af904 BS |
108 | /* Notify the backend that we have completed emitting the data for a |
109 | decl. */ | |
110 | DEFHOOK | |
111 | (decl_end, | |
112 | "Define this hook if the target assembler requires a special marker to\n\ | |
113 | terminate an initialized variable declaration.", | |
114 | void, (void), | |
115 | hook_void_void) | |
116 | ||
38f8b050 JR |
117 | /* Output code that will globalize a label. */ |
118 | DEFHOOK | |
119 | (globalize_label, | |
673c2f63 JM |
120 | "This target hook is a function to output to the stdio stream\n\ |
121 | @var{stream} some commands that will make the label @var{name} global;\n\ | |
122 | that is, available for reference from other files.\n\ | |
123 | \n\ | |
124 | The default implementation relies on a proper definition of\n\ | |
125 | @code{GLOBAL_ASM_OP}.", | |
38f8b050 JR |
126 | void, (FILE *stream, const char *name), |
127 | default_globalize_label) | |
128 | ||
129 | /* Output code that will globalize a declaration. */ | |
130 | DEFHOOK | |
131 | (globalize_decl_name, | |
673c2f63 JM |
132 | "This target hook is a function to output to the stdio stream\n\ |
133 | @var{stream} some commands that will make the name associated with @var{decl}\n\ | |
134 | global; that is, available for reference from other files.\n\ | |
135 | \n\ | |
136 | The default implementation uses the TARGET_ASM_GLOBALIZE_LABEL target hook.", | |
38f8b050 JR |
137 | void, (FILE *stream, tree decl), default_globalize_decl_name) |
138 | ||
0d4b5b86 BS |
139 | /* Output code that will declare an external variable. */ |
140 | DEFHOOK | |
141 | (assemble_undefined_decl, | |
142 | "This target hook is a function to output to the stdio stream\n\ | |
143 | @var{stream} some commands that will declare the name associated with\n\ | |
144 | @var{decl} which is not defined in the current translation unit. Most\n\ | |
145 | assemblers do not require anything to be output in this case.", | |
146 | void, (FILE *stream, const char *name, const_tree decl), | |
147 | hook_void_FILEptr_constcharptr_const_tree) | |
148 | ||
38f8b050 JR |
149 | /* Output code that will emit a label for unwind info, if this |
150 | target requires such labels. Second argument is the decl the | |
151 | unwind info is associated with, third is a boolean: true if | |
152 | this is for exception handling, fourth is a boolean: true if | |
153 | this is only a placeholder for an omitted FDE. */ | |
154 | DEFHOOK | |
155 | (emit_unwind_label, | |
673c2f63 JM |
156 | "This target hook emits a label at the beginning of each FDE@. It\n\ |
157 | should be defined on targets where FDEs need special labels, and it\n\ | |
158 | should write the appropriate label, for the FDE associated with the\n\ | |
159 | function declaration @var{decl}, to the stdio stream @var{stream}.\n\ | |
160 | The third argument, @var{for_eh}, is a boolean: true if this is for an\n\ | |
161 | exception table. The fourth argument, @var{empty}, is a boolean:\n\ | |
162 | true if this is a placeholder label for an omitted FDE@.\n\ | |
163 | \n\ | |
164 | The default is that FDEs are not given nonlocal labels.", | |
38f8b050 JR |
165 | void, (FILE *stream, tree decl, int for_eh, int empty), |
166 | default_emit_unwind_label) | |
167 | ||
168 | /* Output code that will emit a label to divide up the exception table. */ | |
169 | DEFHOOK | |
170 | (emit_except_table_label, | |
673c2f63 JM |
171 | "This target hook emits a label at the beginning of the exception table.\n\ |
172 | It should be defined on targets where it is desirable for the table\n\ | |
173 | to be broken up according to function.\n\ | |
174 | \n\ | |
175 | The default is that no label is emitted.", | |
38f8b050 JR |
176 | void, (FILE *stream), |
177 | default_emit_except_table_label) | |
178 | ||
a68b5e52 RH |
179 | /* Emit a directive for setting the personality for the function. */ |
180 | DEFHOOK | |
181 | (emit_except_personality, | |
4d3907c2 ML |
182 | "If the target implements @code{TARGET_ASM_UNWIND_EMIT}, this hook may be\n\ |
183 | used to emit a directive to install a personality hook into the unwind\n\ | |
184 | info. This hook should not be used if dwarf2 unwind info is used.", | |
a68b5e52 RH |
185 | void, (rtx personality), |
186 | NULL) | |
187 | ||
5d46ec3d IS |
188 | /* If necessary, modify personality and LSDA references to handle |
189 | indirection. This is used when the assembler supports CFI directives. */ | |
190 | DEFHOOK | |
191 | (make_eh_symbol_indirect, | |
4d3907c2 ML |
192 | "If necessary, modify personality and LSDA references to handle indirection.\n\ |
193 | The original symbol is in @code{origsymbol} and if @code{pubvis} is true\n\ | |
194 | the symbol is visible outside the TU.", | |
5d46ec3d IS |
195 | rtx, (rtx origsymbol, bool pubvis), |
196 | NULL) | |
197 | ||
38f8b050 JR |
198 | /* Emit any directives required to unwind this instruction. */ |
199 | DEFHOOK | |
200 | (unwind_emit, | |
673c2f63 JM |
201 | "This target hook emits assembly directives required to unwind the\n\ |
202 | given instruction. This is only used when @code{TARGET_EXCEPT_UNWIND_INFO}\n\ | |
203 | returns @code{UI_TARGET}.", | |
ac44248e | 204 | void, (FILE *stream, rtx_insn *insn), |
2784ed9c | 205 | NULL) |
38f8b050 | 206 | |
3bc6b3e6 RH |
207 | DEFHOOKPOD |
208 | (unwind_emit_before_insn, | |
4d3907c2 ML |
209 | "True if the @code{TARGET_ASM_UNWIND_EMIT} hook should be called before\n\ |
210 | the assembly for @var{insn} has been emitted, false if the hook should\n\ | |
211 | be called afterward.", | |
3bc6b3e6 RH |
212 | bool, true) |
213 | ||
491d5b3c IS |
214 | /* Return true if the target needs extra instructions to restore the current |
215 | frame address after a DW_CFA_restore_state opcode. */ | |
216 | DEFHOOK | |
217 | (should_restore_cfa_state, | |
4d3907c2 ML |
218 | "For DWARF-based unwind frames, two CFI instructions provide for save and\n\ |
219 | restore of register state. GCC maintains the current frame address (CFA)\n\ | |
220 | separately from the register bank but the unwinder in libgcc preserves this\n\ | |
221 | state along with the registers (and this is expected by the code that writes\n\ | |
222 | the unwind frames). This hook allows the target to specify that the CFA data\n\ | |
223 | is not saved/restored along with the registers by the target unwinder so that\n\ | |
224 | suitable additional instructions should be emitted to restore it.", | |
491d5b3c IS |
225 | bool, (void), |
226 | hook_bool_void_false) | |
227 | ||
4ee3b013 JR |
228 | /* Generate an internal label. |
229 | For now this is just a wrapper for ASM_GENERATE_INTERNAL_LABEL. */ | |
230 | DEFHOOK_UNDOC | |
231 | (generate_internal_label, | |
232 | "", | |
233 | void, (char *buf, const char *prefix, unsigned long labelno), | |
234 | default_generate_internal_label) | |
235 | ||
38f8b050 JR |
236 | /* Output an internal label. */ |
237 | DEFHOOK | |
238 | (internal_label, | |
673c2f63 JM |
239 | "A function to output to the stdio stream @var{stream} a label whose\n\ |
240 | name is made from the string @var{prefix} and the number @var{labelno}.\n\ | |
241 | \n\ | |
242 | It is absolutely essential that these labels be distinct from the labels\n\ | |
243 | used for user-level functions and variables. Otherwise, certain programs\n\ | |
244 | will have name conflicts with internal labels.\n\ | |
245 | \n\ | |
246 | It is desirable to exclude internal labels from the symbol table of the\n\ | |
247 | object file. Most assemblers have a naming convention for labels that\n\ | |
248 | should be excluded; on many systems, the letter @samp{L} at the\n\ | |
249 | beginning of a label has this effect. You should find out what\n\ | |
250 | convention your system uses, and follow it.\n\ | |
251 | \n\ | |
252 | The default version of this function utilizes @code{ASM_GENERATE_INTERNAL_LABEL}.", | |
38f8b050 JR |
253 | void, (FILE *stream, const char *prefix, unsigned long labelno), |
254 | default_internal_label) | |
255 | ||
256 | /* Output label for the constant. */ | |
ad78130c | 257 | DEFHOOK |
38f8b050 | 258 | (declare_constant_name, |
673c2f63 JM |
259 | "A target hook to output to the stdio stream @var{file} any text necessary\n\ |
260 | for declaring the name @var{name} of a constant which is being defined. This\n\ | |
261 | target hook is responsible for outputting the label definition (perhaps using\n\ | |
262 | @code{assemble_label}). The argument @var{exp} is the value of the constant,\n\ | |
263 | and @var{size} is the size of the constant in bytes. The @var{name}\n\ | |
264 | will be an internal label.\n\ | |
265 | \n\ | |
266 | The default version of this target hook, define the @var{name} in the\n\ | |
267 | usual manner as a label (by means of @code{assemble_label}).\n\ | |
268 | \n\ | |
269 | You may wish to use @code{ASM_OUTPUT_TYPE_DIRECTIVE} in this target hook.", | |
ad78130c | 270 | void, (FILE *file, const char *name, const_tree expr, HOST_WIDE_INT size), |
38f8b050 JR |
271 | default_asm_declare_constant_name) |
272 | ||
273 | /* Emit a ttype table reference to a typeinfo object. */ | |
274 | DEFHOOK | |
275 | (ttype, | |
673c2f63 JM |
276 | "This hook is used to output a reference from a frame unwinding table to\n\ |
277 | the type_info object identified by @var{sym}. It should return @code{true}\n\ | |
278 | if the reference was output. Returning @code{false} will cause the\n\ | |
279 | reference to be output using the normal Dwarf2 routines.", | |
38f8b050 JR |
280 | bool, (rtx sym), |
281 | hook_bool_rtx_false) | |
282 | ||
283 | /* Emit an assembler directive to set visibility for the symbol | |
284 | associated with the tree decl. */ | |
285 | DEFHOOK | |
286 | (assemble_visibility, | |
673c2f63 JM |
287 | "This target hook is a function to output to @var{asm_out_file} some\n\ |
288 | commands that will make the symbol(s) associated with @var{decl} have\n\ | |
289 | hidden, protected or internal visibility as specified by @var{visibility}.", | |
38f8b050 JR |
290 | void, (tree decl, int visibility), |
291 | default_assemble_visibility) | |
292 | ||
417ca011 TD |
293 | DEFHOOK |
294 | (print_patchable_function_entry, | |
295 | "Generate a patchable area at the function start, consisting of\n\ | |
296 | @var{patch_area_size} NOP instructions. If the target supports named\n\ | |
297 | sections and if @var{record_p} is true, insert a pointer to the current\n\ | |
298 | location in the table of patchable functions. The default implementation\n\ | |
299 | of the hook places the table of pointers in the special section named\n\ | |
300 | @code{__patchable_function_entries}.", | |
301 | void, (FILE *file, unsigned HOST_WIDE_INT patch_area_size, bool record_p), | |
302 | default_print_patchable_function_entry) | |
303 | ||
38f8b050 JR |
304 | /* Output the assembler code for entry to a function. */ |
305 | DEFHOOK | |
306 | (function_prologue, | |
673c2f63 JM |
307 | "If defined, a function that outputs the assembler code for entry to a\n\ |
308 | function. The prologue is responsible for setting up the stack frame,\n\ | |
309 | initializing the frame pointer register, saving registers that must be\n\ | |
310 | saved, and allocating @var{size} additional bytes of storage for the\n\ | |
42776416 RS |
311 | local variables. @var{file} is a stdio stream to which the assembler\n\ |
312 | code should be output.\n\ | |
673c2f63 JM |
313 | \n\ |
314 | The label for the beginning of the function need not be output by this\n\ | |
315 | macro. That has already been done when the macro is run.\n\ | |
316 | \n\ | |
317 | @findex regs_ever_live\n\ | |
318 | To determine which registers to save, the macro can refer to the array\n\ | |
319 | @code{regs_ever_live}: element @var{r} is nonzero if hard register\n\ | |
320 | @var{r} is used anywhere within the function. This implies the function\n\ | |
321 | prologue should save register @var{r}, provided it is not one of the\n\ | |
322 | call-used registers. (@code{TARGET_ASM_FUNCTION_EPILOGUE} must likewise use\n\ | |
323 | @code{regs_ever_live}.)\n\ | |
324 | \n\ | |
325 | On machines that have ``register windows'', the function entry code does\n\ | |
326 | not save on the stack the registers that are in the windows, even if\n\ | |
327 | they are supposed to be preserved by function calls; instead it takes\n\ | |
328 | appropriate steps to ``push'' the register stack, if any non-call-used\n\ | |
329 | registers are used in the function.\n\ | |
330 | \n\ | |
331 | @findex frame_pointer_needed\n\ | |
332 | On machines where functions may or may not have frame-pointers, the\n\ | |
333 | function entry code must vary accordingly; it must set up the frame\n\ | |
334 | pointer if one is wanted, and not otherwise. To determine whether a\n\ | |
335 | frame pointer is in wanted, the macro can refer to the variable\n\ | |
336 | @code{frame_pointer_needed}. The variable's value will be 1 at run\n\ | |
337 | time in a function that needs a frame pointer. @xref{Elimination}.\n\ | |
338 | \n\ | |
339 | The function entry code is responsible for allocating any stack space\n\ | |
340 | required for the function. This stack space consists of the regions\n\ | |
341 | listed below. In most cases, these regions are allocated in the\n\ | |
342 | order listed, with the last listed region closest to the top of the\n\ | |
343 | stack (the lowest address if @code{STACK_GROWS_DOWNWARD} is defined, and\n\ | |
344 | the highest address if it is not defined). You can use a different order\n\ | |
345 | for a machine if doing so is more convenient or required for\n\ | |
346 | compatibility reasons. Except in cases where required by standard\n\ | |
347 | or by a debugger, there is no reason why the stack layout used by GCC\n\ | |
348 | need agree with that used by other compilers for a machine.", | |
42776416 | 349 | void, (FILE *file), |
38f8b050 JR |
350 | default_function_pro_epilogue) |
351 | ||
352 | /* Output the assembler code for end of prologue. */ | |
353 | DEFHOOK | |
354 | (function_end_prologue, | |
673c2f63 JM |
355 | "If defined, a function that outputs assembler code at the end of a\n\ |
356 | prologue. This should be used when the function prologue is being\n\ | |
357 | emitted as RTL, and you have some extra assembler that needs to be\n\ | |
358 | emitted. @xref{prologue instruction pattern}.", | |
38f8b050 JR |
359 | void, (FILE *file), |
360 | no_asm_to_stream) | |
361 | ||
362 | /* Output the assembler code for start of epilogue. */ | |
363 | DEFHOOK | |
364 | (function_begin_epilogue, | |
673c2f63 JM |
365 | "If defined, a function that outputs assembler code at the start of an\n\ |
366 | epilogue. This should be used when the function epilogue is being\n\ | |
367 | emitted as RTL, and you have some extra assembler that needs to be\n\ | |
368 | emitted. @xref{epilogue instruction pattern}.", | |
38f8b050 JR |
369 | void, (FILE *file), |
370 | no_asm_to_stream) | |
371 | ||
372 | /* Output the assembler code for function exit. */ | |
373 | DEFHOOK | |
374 | (function_epilogue, | |
673c2f63 JM |
375 | "If defined, a function that outputs the assembler code for exit from a\n\ |
376 | function. The epilogue is responsible for restoring the saved\n\ | |
377 | registers and stack pointer to their values when the function was\n\ | |
378 | called, and returning control to the caller. This macro takes the\n\ | |
42776416 | 379 | same argument as the macro @code{TARGET_ASM_FUNCTION_PROLOGUE}, and the\n\ |
673c2f63 JM |
380 | registers to restore are determined from @code{regs_ever_live} and\n\ |
381 | @code{CALL_USED_REGISTERS} in the same way.\n\ | |
382 | \n\ | |
383 | On some machines, there is a single instruction that does all the work\n\ | |
384 | of returning from the function. On these machines, give that\n\ | |
385 | instruction the name @samp{return} and do not define the macro\n\ | |
386 | @code{TARGET_ASM_FUNCTION_EPILOGUE} at all.\n\ | |
387 | \n\ | |
388 | Do not define a pattern named @samp{return} if you want the\n\ | |
389 | @code{TARGET_ASM_FUNCTION_EPILOGUE} to be used. If you want the target\n\ | |
390 | switches to control whether return instructions or epilogues are used,\n\ | |
391 | define a @samp{return} pattern with a validity condition that tests the\n\ | |
392 | target switches appropriately. If the @samp{return} pattern's validity\n\ | |
393 | condition is false, epilogues will be used.\n\ | |
394 | \n\ | |
395 | On machines where functions may or may not have frame-pointers, the\n\ | |
396 | function exit code must vary accordingly. Sometimes the code for these\n\ | |
397 | two cases is completely different. To determine whether a frame pointer\n\ | |
398 | is wanted, the macro can refer to the variable\n\ | |
399 | @code{frame_pointer_needed}. The variable's value will be 1 when compiling\n\ | |
400 | a function that needs a frame pointer.\n\ | |
401 | \n\ | |
402 | Normally, @code{TARGET_ASM_FUNCTION_PROLOGUE} and\n\ | |
403 | @code{TARGET_ASM_FUNCTION_EPILOGUE} must treat leaf functions specially.\n\ | |
404 | The C variable @code{current_function_is_leaf} is nonzero for such a\n\ | |
405 | function. @xref{Leaf Functions}.\n\ | |
406 | \n\ | |
407 | On some machines, some functions pop their arguments on exit while\n\ | |
408 | others leave that for the caller to do. For example, the 68020 when\n\ | |
409 | given @option{-mrtd} pops arguments in functions that take a fixed\n\ | |
410 | number of arguments.\n\ | |
411 | \n\ | |
412 | @findex pops_args\n\ | |
413 | @findex crtl->args.pops_args\n\ | |
414 | Your definition of the macro @code{RETURN_POPS_ARGS} decides which\n\ | |
415 | functions pop their own arguments. @code{TARGET_ASM_FUNCTION_EPILOGUE}\n\ | |
416 | needs to know what was decided. The number of bytes of the current\n\ | |
417 | function's arguments that this function should pop is available in\n\ | |
418 | @code{crtl->args.pops_args}. @xref{Scalar Return}.", | |
42776416 | 419 | void, (FILE *file), |
38f8b050 JR |
420 | default_function_pro_epilogue) |
421 | ||
422 | /* Initialize target-specific sections. */ | |
423 | DEFHOOK | |
424 | (init_sections, | |
673c2f63 | 425 | "Define this hook if you need to do something special to set up the\n\ |
e53b6e56 | 426 | @file{varasm.cc} sections, or if your target has some special sections\n\ |
673c2f63 JM |
427 | of its own that you need to create.\n\ |
428 | \n\ | |
429 | GCC calls this hook after processing the command line, but before writing\n\ | |
430 | any assembly code, and before calling any of the section-returning hooks\n\ | |
431 | described below.", | |
38f8b050 JR |
432 | void, (void), |
433 | hook_void_void) | |
434 | ||
435 | /* Tell assembler to change to section NAME with attributes FLAGS. | |
436 | If DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with | |
437 | which this section is associated. */ | |
438 | DEFHOOK | |
439 | (named_section, | |
673c2f63 JM |
440 | "Output assembly directives to switch to section @var{name}. The section\n\ |
441 | should have attributes as specified by @var{flags}, which is a bit mask\n\ | |
442 | of the @code{SECTION_*} flags defined in @file{output.h}. If @var{decl}\n\ | |
443 | is non-NULL, it is the @code{VAR_DECL} or @code{FUNCTION_DECL} with which\n\ | |
444 | this section is associated.", | |
38f8b050 JR |
445 | void, (const char *name, unsigned int flags, tree decl), |
446 | default_no_named_section) | |
447 | ||
0ee70cc0 AV |
448 | /* Tell assembler what section attributes to assign this elf section |
449 | declaration, using their numerical value. */ | |
450 | DEFHOOK | |
451 | (elf_flags_numeric, | |
452 | "This hook can be used to encode ELF section flags for which no letter\n\ | |
453 | code has been defined in the assembler. It is called by\n\ | |
454 | @code{default_asm_named_section} whenever the section flags need to be\n\ | |
455 | emitted in the assembler output. If the hook returns true, then the\n\ | |
456 | numerical value for ELF section flags should be calculated from\n\ | |
759a6472 AV |
457 | @var{flags} and saved in @var{*num}; the value is printed out instead of the\n\ |
458 | normal sequence of letter codes. If the hook is not defined, or if it\n\ | |
459 | returns false, then @var{num} is ignored and the traditional letter sequence\n\ | |
460 | is emitted.", | |
0ee70cc0 | 461 | bool, (unsigned int flags, unsigned int *num), |
bf072854 | 462 | hook_bool_uint_uintp_false) |
0ee70cc0 | 463 | |
f16d3f39 JH |
464 | /* Return preferred text (sub)section for function DECL. |
465 | Main purpose of this function is to separate cold, normal and hot | |
466 | functions. STARTUP is true when function is known to be used only | |
467 | at startup (from static constructors or it is main()). | |
468 | EXIT is true when function is known to be used only at exit | |
469 | (from static destructors). | |
470 | Return NULL if function should go to default text section. */ | |
471 | DEFHOOK | |
472 | (function_section, | |
673c2f63 JM |
473 | "Return preferred text (sub)section for function @var{decl}.\n\ |
474 | Main purpose of this function is to separate cold, normal and hot\n\ | |
475 | functions. @var{startup} is true when function is known to be used only\n\ | |
476 | at startup (from static constructors or it is @code{main()}).\n\ | |
477 | @var{exit} is true when function is known to be used only at exit\n\ | |
478 | (from static destructors).\n\ | |
479 | Return NULL if function should go to default text section.", | |
f16d3f39 JH |
480 | section *, (tree decl, enum node_frequency freq, bool startup, bool exit), |
481 | default_function_section) | |
482 | ||
14d11d40 IS |
483 | /* Output the assembler code for function exit. */ |
484 | DEFHOOK | |
485 | (function_switched_text_sections, | |
4d3907c2 ML |
486 | "Used by the target to emit any assembler directives or additional\n\ |
487 | labels needed when a function is partitioned between different\n\ | |
488 | sections. Output should be written to @var{file}. The function\n\ | |
489 | decl is available as @var{decl} and the new section is `cold' if\n\ | |
490 | @var{new_is_cold} is @code{true}.", | |
14d11d40 IS |
491 | void, (FILE *file, tree decl, bool new_is_cold), |
492 | default_function_switched_text_sections) | |
493 | ||
38f8b050 JR |
494 | /* Return a mask describing how relocations should be treated when |
495 | selecting sections. Bit 1 should be set if global relocations | |
496 | should be placed in a read-write section; bit 0 should be set if | |
497 | local relocations should be placed in a read-write section. */ | |
498 | DEFHOOK | |
499 | (reloc_rw_mask, | |
673c2f63 JM |
500 | "Return a mask describing how relocations should be treated when\n\ |
501 | selecting sections. Bit 1 should be set if global relocations\n\ | |
502 | should be placed in a read-write section; bit 0 should be set if\n\ | |
503 | local relocations should be placed in a read-write section.\n\ | |
504 | \n\ | |
505 | The default version of this function returns 3 when @option{-fpic}\n\ | |
506 | is in effect, and 0 otherwise. The hook is typically redefined\n\ | |
507 | when the target cannot support (some kinds of) dynamic relocations\n\ | |
508 | in read-only sections even in executables.", | |
38f8b050 JR |
509 | int, (void), |
510 | default_reloc_rw_mask) | |
511 | ||
af1682fc AS |
512 | /* Return a flag for either generating ADDR_DIF_VEC table |
513 | or ADDR_VEC table for jumps in case of -fPIC/-fPIE. */ | |
514 | DEFHOOK | |
515 | (generate_pic_addr_diff_vec, | |
516 | "Return true to generate ADDR_DIF_VEC table\n\ | |
517 | or false to generate ADDR_VEC table for jumps in case of -fPIC.\n\ | |
518 | \n\ | |
519 | The default version of this function returns true if flag_pic\n\ | |
520 | equals true and false otherwise", | |
521 | bool, (void), | |
522 | default_generate_pic_addr_diff_vec) | |
523 | ||
38f8b050 JR |
524 | /* Return a section for EXP. It may be a DECL or a constant. RELOC |
525 | is nonzero if runtime relocations must be applied; bit 1 will be | |
526 | set if the runtime relocations require non-local name resolution. | |
527 | ALIGN is the required alignment of the data. */ | |
528 | DEFHOOK | |
529 | (select_section, | |
673c2f63 JM |
530 | "Return the section into which @var{exp} should be placed. You can\n\ |
531 | assume that @var{exp} is either a @code{VAR_DECL} node or a constant of\n\ | |
532 | some sort. @var{reloc} indicates whether the initial value of @var{exp}\n\ | |
533 | requires link-time relocations. Bit 0 is set when variable contains\n\ | |
534 | local relocations only, while bit 1 is set for global relocations.\n\ | |
535 | @var{align} is the constant alignment in bits.\n\ | |
536 | \n\ | |
537 | The default version of this function takes care of putting read-only\n\ | |
538 | variables in @code{readonly_data_section}.\n\ | |
539 | \n\ | |
540 | See also @var{USE_SELECT_SECTION_FOR_FUNCTIONS}.", | |
38f8b050 JR |
541 | section *, (tree exp, int reloc, unsigned HOST_WIDE_INT align), |
542 | default_select_section) | |
543 | ||
544 | /* Return a section for X. MODE is X's mode and ALIGN is its | |
545 | alignment in bits. */ | |
546 | DEFHOOK | |
547 | (select_rtx_section, | |
673c2f63 JM |
548 | "Return the section into which a constant @var{x}, of mode @var{mode},\n\ |
549 | should be placed. You can assume that @var{x} is some kind of\n\ | |
550 | constant in RTL@. The argument @var{mode} is redundant except in the\n\ | |
551 | case of a @code{const_int} rtx. @var{align} is the constant alignment\n\ | |
552 | in bits.\n\ | |
553 | \n\ | |
554 | The default version of this function takes care of putting symbolic\n\ | |
555 | constants in @code{flag_pic} mode in @code{data_section} and everything\n\ | |
556 | else in @code{readonly_data_section}.", | |
ef4bddc2 | 557 | section *, (machine_mode mode, rtx x, unsigned HOST_WIDE_INT align), |
38f8b050 JR |
558 | default_select_rtx_section) |
559 | ||
560 | /* Select a unique section name for DECL. RELOC is the same as | |
561 | for SELECT_SECTION. */ | |
562 | DEFHOOK | |
563 | (unique_section, | |
673c2f63 JM |
564 | "Build up a unique section name, expressed as a @code{STRING_CST} node,\n\ |
565 | and assign it to @samp{DECL_SECTION_NAME (@var{decl})}.\n\ | |
566 | As with @code{TARGET_ASM_SELECT_SECTION}, @var{reloc} indicates whether\n\ | |
567 | the initial value of @var{exp} requires link-time relocations.\n\ | |
568 | \n\ | |
569 | The default version of this function appends the symbol name to the\n\ | |
570 | ELF section name that would normally be used for the symbol. For\n\ | |
571 | example, the function @code{foo} would be placed in @code{.text.foo}.\n\ | |
572 | Whatever the actual target object format, this is often good enough.", | |
38f8b050 JR |
573 | void, (tree decl, int reloc), |
574 | default_unique_section) | |
575 | ||
d5ac0401 HG |
576 | /* Return the readonly data or relocated readonly data section |
577 | associated with function DECL. */ | |
38f8b050 JR |
578 | DEFHOOK |
579 | (function_rodata_section, | |
d5ac0401 HG |
580 | "Return the readonly data or reloc readonly data section associated with\n\ |
581 | @samp{DECL_SECTION_NAME (@var{decl})}. @var{relocatable} selects the latter\n\ | |
582 | over the former.\n\ | |
673c2f63 JM |
583 | The default version of this function selects @code{.gnu.linkonce.r.name} if\n\ |
584 | the function's section is @code{.gnu.linkonce.t.name}, @code{.rodata.name}\n\ | |
d5ac0401 HG |
585 | or @code{.data.rel.ro.name} if function is in @code{.text.name}, and\n\ |
586 | the normal readonly-data or reloc readonly data section otherwise.", | |
587 | section *, (tree decl, bool relocatable), | |
38f8b050 JR |
588 | default_function_rodata_section) |
589 | ||
727a65e6 BS |
590 | /* Nonnull if the target wants to override the default ".rodata" prefix |
591 | for mergeable data sections. */ | |
592 | DEFHOOKPOD | |
593 | (mergeable_rodata_prefix, | |
594 | "Usually, the compiler uses the prefix @code{\".rodata\"} to construct\n\ | |
595 | section names for mergeable constant data. Define this macro to override\n\ | |
596 | the string if a different section name should be used.", | |
597 | const char *, ".rodata") | |
598 | ||
50b0b78a IS |
599 | /* Return the section to be used for transactional memory clone tables. */ |
600 | DEFHOOK | |
601 | (tm_clone_table_section, | |
4d3907c2 ML |
602 | "Return the section that should be used for transactional memory clone\n\ |
603 | tables.", | |
50b0b78a IS |
604 | section *, (void), default_clone_table_section) |
605 | ||
38f8b050 JR |
606 | /* Output a constructor for a symbol with a given priority. */ |
607 | DEFHOOK | |
608 | (constructor, | |
673c2f63 JM |
609 | "If defined, a function that outputs assembler code to arrange to call\n\ |
610 | the function referenced by @var{symbol} at initialization time.\n\ | |
611 | \n\ | |
612 | Assume that @var{symbol} is a @code{SYMBOL_REF} for a function taking\n\ | |
613 | no arguments and with no return value. If the target supports initialization\n\ | |
614 | priorities, @var{priority} is a value between 0 and @code{MAX_INIT_PRIORITY};\n\ | |
615 | otherwise it must be @code{DEFAULT_INIT_PRIORITY}.\n\ | |
616 | \n\ | |
617 | If this macro is not defined by the target, a suitable default will\n\ | |
618 | be chosen if (1) the target supports arbitrary section names, (2) the\n\ | |
619 | target defines @code{CTORS_SECTION_ASM_OP}, or (3) @code{USE_COLLECT2}\n\ | |
620 | is not defined.", | |
38f8b050 JR |
621 | void, (rtx symbol, int priority), NULL) |
622 | ||
623 | /* Output a destructor for a symbol with a given priority. */ | |
624 | DEFHOOK | |
625 | (destructor, | |
673c2f63 JM |
626 | "This is like @code{TARGET_ASM_CONSTRUCTOR} but used for termination\n\ |
627 | functions rather than initialization functions.", | |
38f8b050 JR |
628 | void, (rtx symbol, int priority), NULL) |
629 | ||
630 | /* Output the assembler code for a thunk function. THUNK_DECL is the | |
631 | declaration for the thunk function itself, FUNCTION is the decl for | |
632 | the target function. DELTA is an immediate constant offset to be | |
633 | added to THIS. If VCALL_OFFSET is nonzero, the word at | |
634 | *(*this + vcall_offset) should be added to THIS. */ | |
635 | DEFHOOK | |
636 | (output_mi_thunk, | |
673c2f63 JM |
637 | "A function that outputs the assembler code for a thunk\n\ |
638 | function, used to implement C++ virtual function calls with multiple\n\ | |
639 | inheritance. The thunk acts as a wrapper around a virtual function,\n\ | |
640 | adjusting the implicit object parameter before handing control off to\n\ | |
641 | the real function.\n\ | |
642 | \n\ | |
643 | First, emit code to add the integer @var{delta} to the location that\n\ | |
644 | contains the incoming first argument. Assume that this argument\n\ | |
645 | contains a pointer, and is the one used to pass the @code{this} pointer\n\ | |
646 | in C++. This is the incoming argument @emph{before} the function prologue,\n\ | |
647 | e.g.@: @samp{%o0} on a sparc. The addition must preserve the values of\n\ | |
648 | all other incoming arguments.\n\ | |
649 | \n\ | |
650 | Then, if @var{vcall_offset} is nonzero, an additional adjustment should be\n\ | |
651 | made after adding @code{delta}. In particular, if @var{p} is the\n\ | |
652 | adjusted pointer, the following adjustment should be made:\n\ | |
653 | \n\ | |
654 | @smallexample\n\ | |
655 | p += (*((ptrdiff_t **)p))[vcall_offset/sizeof(ptrdiff_t)]\n\ | |
656 | @end smallexample\n\ | |
657 | \n\ | |
658 | After the additions, emit code to jump to @var{function}, which is a\n\ | |
659 | @code{FUNCTION_DECL}. This is a direct pure jump, not a call, and does\n\ | |
660 | not touch the return address. Hence returning from @var{FUNCTION} will\n\ | |
661 | return to whoever called the current @samp{thunk}.\n\ | |
662 | \n\ | |
663 | The effect must be as if @var{function} had been called directly with\n\ | |
664 | the adjusted first argument. This macro is responsible for emitting all\n\ | |
665 | of the code for a thunk function; @code{TARGET_ASM_FUNCTION_PROLOGUE}\n\ | |
666 | and @code{TARGET_ASM_FUNCTION_EPILOGUE} are not invoked.\n\ | |
667 | \n\ | |
668 | The @var{thunk_fndecl} is redundant. (@var{delta} and @var{function}\n\ | |
669 | have already been extracted from it.) It might possibly be useful on\n\ | |
670 | some targets, but probably not.\n\ | |
671 | \n\ | |
672 | If you do not define this macro, the target-independent code in the C++\n\ | |
673 | front end will generate a less efficient heavyweight thunk that calls\n\ | |
674 | @var{function} instead of jumping to it. The generic approach does\n\ | |
675 | not support varargs.", | |
38f8b050 JR |
676 | void, (FILE *file, tree thunk_fndecl, HOST_WIDE_INT delta, |
677 | HOST_WIDE_INT vcall_offset, tree function), | |
678 | NULL) | |
679 | ||
680 | /* Determine whether output_mi_thunk would succeed. */ | |
681 | /* ??? Ideally, this hook would not exist, and success or failure | |
682 | would be returned from output_mi_thunk directly. But there's | |
683 | too much undo-able setup involved in invoking output_mi_thunk. | |
684 | Could be fixed by making output_mi_thunk emit rtl instead of | |
685 | text to the output file. */ | |
686 | DEFHOOK | |
687 | (can_output_mi_thunk, | |
673c2f63 JM |
688 | "A function that returns true if TARGET_ASM_OUTPUT_MI_THUNK would be able\n\ |
689 | to output the assembler code for the thunk function specified by the\n\ | |
690 | arguments it is passed, and false otherwise. In the latter case, the\n\ | |
691 | generic approach will be used by the C++ front end, with the limitations\n\ | |
692 | previously exposed.", | |
38f8b050 JR |
693 | bool, (const_tree thunk_fndecl, HOST_WIDE_INT delta, |
694 | HOST_WIDE_INT vcall_offset, const_tree function), | |
695 | hook_bool_const_tree_hwi_hwi_const_tree_false) | |
696 | ||
697 | /* Output any boilerplate text needed at the beginning of a | |
698 | translation unit. */ | |
699 | DEFHOOK | |
700 | (file_start, | |
673c2f63 JM |
701 | "Output to @code{asm_out_file} any text which the assembler expects to\n\ |
702 | find at the beginning of a file. The default behavior is controlled\n\ | |
703 | by two flags, documented below. Unless your target's assembler is\n\ | |
704 | quite unusual, if you override the default, you should call\n\ | |
705 | @code{default_file_start} at some point in your target hook. This\n\ | |
706 | lets other target files rely on these variables.", | |
38f8b050 JR |
707 | void, (void), |
708 | default_file_start) | |
709 | ||
710 | /* Output any boilerplate text needed at the end of a translation unit. */ | |
711 | DEFHOOK | |
712 | (file_end, | |
673c2f63 JM |
713 | "Output to @code{asm_out_file} any text which the assembler expects\n\ |
714 | to find at the end of a file. The default is to output nothing.", | |
38f8b050 JR |
715 | void, (void), |
716 | hook_void_void) | |
717 | ||
718 | /* Output any boilerplate text needed at the beginning of an | |
719 | LTO output stream. */ | |
720 | DEFHOOK | |
721 | (lto_start, | |
673c2f63 JM |
722 | "Output to @code{asm_out_file} any text which the assembler expects\n\ |
723 | to find at the start of an LTO section. The default is to output\n\ | |
724 | nothing.", | |
38f8b050 JR |
725 | void, (void), |
726 | hook_void_void) | |
727 | ||
728 | /* Output any boilerplate text needed at the end of an | |
729 | LTO output stream. */ | |
730 | DEFHOOK | |
731 | (lto_end, | |
673c2f63 JM |
732 | "Output to @code{asm_out_file} any text which the assembler expects\n\ |
733 | to find at the end of an LTO section. The default is to output\n\ | |
734 | nothing.", | |
38f8b050 JR |
735 | void, (void), |
736 | hook_void_void) | |
737 | ||
738 | /* Output any boilerplace text needed at the end of a | |
739 | translation unit before debug and unwind info is emitted. */ | |
740 | DEFHOOK | |
741 | (code_end, | |
673c2f63 JM |
742 | "Output to @code{asm_out_file} any text which is needed before emitting\n\ |
743 | unwind info and debug info at the end of a file. Some targets emit\n\ | |
744 | here PIC setup thunks that cannot be emitted at the end of file,\n\ | |
745 | because they couldn't have unwind info then. The default is to output\n\ | |
746 | nothing.", | |
38f8b050 JR |
747 | void, (void), |
748 | hook_void_void) | |
749 | ||
750 | /* Output an assembler pseudo-op to declare a library function name | |
751 | external. */ | |
752 | DEFHOOK | |
753 | (external_libcall, | |
673c2f63 JM |
754 | "This target hook is a function to output to @var{asm_out_file} an assembler\n\ |
755 | pseudo-op to declare a library function name external. The name of the\n\ | |
756 | library function is given by @var{symref}, which is a @code{symbol_ref}.", | |
38f8b050 JR |
757 | void, (rtx symref), |
758 | default_external_libcall) | |
759 | ||
760 | /* Output an assembler directive to mark decl live. This instructs | |
761 | linker to not dead code strip this symbol. */ | |
762 | DEFHOOK | |
763 | (mark_decl_preserved, | |
673c2f63 JM |
764 | "This target hook is a function to output to @var{asm_out_file} an assembler\n\ |
765 | directive to annotate @var{symbol} as used. The Darwin target uses the\n\ | |
766 | .no_dead_code_strip directive.", | |
38f8b050 JR |
767 | void, (const char *symbol), |
768 | hook_void_constcharptr) | |
769 | ||
770 | /* Output a record of the command line switches that have been passed. */ | |
771 | DEFHOOK | |
772 | (record_gcc_switches, | |
673c2f63 | 773 | "Provides the target with the ability to record the gcc command line\n\ |
7caa4970 | 774 | switches provided as argument.\n\ |
673c2f63 JM |
775 | \n\ |
776 | By default this hook is set to NULL, but an example implementation is\n\ | |
777 | provided for ELF based targets. Called @var{elf_record_gcc_switches},\n\ | |
778 | it records the switches as ASCII text inside a new, string mergeable\n\ | |
779 | section in the assembler output file. The name of the new section is\n\ | |
780 | provided by the @code{TARGET_ASM_RECORD_GCC_SWITCHES_SECTION} target\n\ | |
781 | hook.", | |
7caa4970 | 782 | void, (const char *), |
38f8b050 JR |
783 | NULL) |
784 | ||
785 | /* The name of the section that the example ELF implementation of | |
786 | record_gcc_switches will use to store the information. Target | |
787 | specific versions of record_gcc_switches may or may not use | |
788 | this information. */ | |
789 | DEFHOOKPOD | |
790 | (record_gcc_switches_section, | |
673c2f63 JM |
791 | "This is the name of the section that will be created by the example\n\ |
792 | ELF implementation of the @code{TARGET_ASM_RECORD_GCC_SWITCHES} target\n\ | |
793 | hook.", | |
38f8b050 JR |
794 | const char *, ".GCC.command.line") |
795 | ||
796 | /* Output the definition of a section anchor. */ | |
797 | DEFHOOK | |
798 | (output_anchor, | |
673c2f63 JM |
799 | "Write the assembly code to define section anchor @var{x}, which is a\n\ |
800 | @code{SYMBOL_REF} for which @samp{SYMBOL_REF_ANCHOR_P (@var{x})} is true.\n\ | |
801 | The hook is called with the assembly output position set to the beginning\n\ | |
802 | of @code{SYMBOL_REF_BLOCK (@var{x})}.\n\ | |
803 | \n\ | |
804 | If @code{ASM_OUTPUT_DEF} is available, the hook's default definition uses\n\ | |
805 | it to define the symbol as @samp{. + SYMBOL_REF_BLOCK_OFFSET (@var{x})}.\n\ | |
806 | If @code{ASM_OUTPUT_DEF} is not available, the hook's default definition\n\ | |
807 | is @code{NULL}, which disables the use of section anchors altogether.", | |
38f8b050 JR |
808 | void, (rtx x), |
809 | default_asm_output_anchor) | |
810 | ||
a8781821 SB |
811 | DEFHOOK |
812 | (output_ident, | |
4d3907c2 ML |
813 | "Output a string based on @var{name}, suitable for the @samp{#ident}\n\ |
814 | directive, or the equivalent directive or pragma in non-C-family languages.\n\ | |
815 | If this hook is not defined, nothing is output for the @samp{#ident}\n\ | |
816 | directive.", | |
a8781821 SB |
817 | void, (const char *name), |
818 | hook_void_constcharptr) | |
819 | ||
38f8b050 JR |
820 | /* Output a DTP-relative reference to a TLS symbol. */ |
821 | DEFHOOK | |
822 | (output_dwarf_dtprel, | |
673c2f63 JM |
823 | "If defined, this target hook is a function which outputs a DTP-relative\n\ |
824 | reference to the given TLS symbol of the specified size.", | |
38f8b050 JR |
825 | void, (FILE *file, int size, rtx x), |
826 | NULL) | |
827 | ||
828 | /* Some target machines need to postscan each insn after it is output. */ | |
829 | DEFHOOK | |
830 | (final_postscan_insn, | |
673c2f63 JM |
831 | "If defined, this target hook is a function which is executed just after the\n\ |
832 | output of assembler code for @var{insn}, to change the mode of the assembler\n\ | |
833 | if necessary.\n\ | |
834 | \n\ | |
835 | Here the argument @var{opvec} is the vector containing the operands\n\ | |
836 | extracted from @var{insn}, and @var{noperands} is the number of\n\ | |
837 | elements of the vector which contain meaningful data for this insn.\n\ | |
838 | The contents of this vector are what was used to convert the insn\n\ | |
839 | template into assembler code, so you can change the assembler mode\n\ | |
840 | by checking the contents of the vector.", | |
ac44248e | 841 | void, (FILE *file, rtx_insn *insn, rtx *opvec, int noperands), |
38f8b050 JR |
842 | NULL) |
843 | ||
844 | /* Emit the trampoline template. This hook may be NULL. */ | |
845 | DEFHOOK | |
846 | (trampoline_template, | |
673c2f63 JM |
847 | "This hook is called by @code{assemble_trampoline_template} to output,\n\ |
848 | on the stream @var{f}, assembler code for a block of data that contains\n\ | |
849 | the constant parts of a trampoline. This code should not include a\n\ | |
850 | label---the label is taken care of automatically.\n\ | |
851 | \n\ | |
852 | If you do not define this hook, it means no template is needed\n\ | |
853 | for the target. Do not define this hook on systems where the block move\n\ | |
854 | code to copy the trampoline into place would be larger than the code\n\ | |
855 | to generate it on the spot.", | |
38f8b050 JR |
856 | void, (FILE *f), |
857 | NULL) | |
858 | ||
b5f5d41d AS |
859 | DEFHOOK |
860 | (output_source_filename, | |
4d3907c2 ML |
861 | "Output DWARF debugging information which indicates that filename\n\ |
862 | @var{name} is the current source file to the stdio stream @var{file}.\n\ | |
863 | \n\ | |
864 | This target hook need not be defined if the standard form of output\n\ | |
865 | for the file format in use is appropriate.", | |
b5f5d41d AS |
866 | void ,(FILE *file, const char *name), |
867 | default_asm_output_source_filename) | |
868 | ||
6cbd8875 AS |
869 | DEFHOOK |
870 | (output_addr_const_extra, | |
673c2f63 JM |
871 | "A target hook to recognize @var{rtx} patterns that @code{output_addr_const}\n\ |
872 | can't deal with, and output assembly code to @var{file} corresponding to\n\ | |
873 | the pattern @var{x}. This may be used to allow machine-dependent\n\ | |
874 | @code{UNSPEC}s to appear within constants.\n\ | |
875 | \n\ | |
876 | If target hook fails to recognize a pattern, it must return @code{false},\n\ | |
877 | so that a standard error message is printed. If it prints an error message\n\ | |
878 | itself, by calling, for example, @code{output_operand_lossage}, it may just\n\ | |
879 | return @code{true}.", | |
6cbd8875 | 880 | bool, (FILE *file, rtx x), |
e1267133 | 881 | hook_bool_FILEptr_rtx_false) |
6cbd8875 | 882 | |
38f8b050 JR |
883 | /* ??? The TARGET_PRINT_OPERAND* hooks are part of the asm_out struct, |
884 | even though that is not reflected in the macro name to override their | |
885 | initializers. */ | |
886 | #undef HOOK_PREFIX | |
887 | #define HOOK_PREFIX "TARGET_" | |
888 | ||
889 | /* Emit a machine-specific insn operand. */ | |
4d00d5dd JR |
890 | /* ??? tm.texi only documents the old macro PRINT_OPERAND, |
891 | not this hook, and uses a different name for the argument FILE. */ | |
38f8b050 JR |
892 | DEFHOOK_UNDOC |
893 | (print_operand, | |
894 | "", | |
895 | void, (FILE *file, rtx x, int code), | |
896 | default_print_operand) | |
897 | ||
898 | /* Emit a machine-specific memory address. */ | |
4d00d5dd JR |
899 | /* ??? tm.texi only documents the old macro PRINT_OPERAND_ADDRESS, |
900 | not this hook, and uses different argument names. */ | |
38f8b050 JR |
901 | DEFHOOK_UNDOC |
902 | (print_operand_address, | |
903 | "", | |
cc8ca59e | 904 | void, (FILE *file, machine_mode mode, rtx addr), |
38f8b050 JR |
905 | default_print_operand_address) |
906 | ||
907 | /* Determine whether CODE is a valid punctuation character for the | |
908 | `print_operand' hook. */ | |
4d00d5dd JR |
909 | /* ??? tm.texi only documents the old macro PRINT_OPERAND_PUNCT_VALID_P, |
910 | not this hook. */ | |
38f8b050 JR |
911 | DEFHOOK_UNDOC |
912 | (print_operand_punct_valid_p, | |
913 | "", | |
914 | bool ,(unsigned char code), | |
915 | default_print_operand_punct_valid_p) | |
916 | ||
77754180 DK |
917 | /* Given a symbol name, perform same mangling as assemble_name and |
918 | ASM_OUTPUT_LABELREF, returning result as an IDENTIFIER_NODE. */ | |
919 | DEFHOOK | |
920 | (mangle_assembler_name, | |
e53b6e56 | 921 | "Given a symbol @var{name}, perform same mangling as @code{varasm.cc}'s\n\ |
4d3907c2 ML |
922 | @code{assemble_name}, but in memory rather than to a file stream, returning\n\ |
923 | result as an @code{IDENTIFIER_NODE}. Required for correct LTO symtabs. The\n\ | |
924 | default implementation calls the @code{TARGET_STRIP_NAME_ENCODING} hook and\n\ | |
925 | then prepends the @code{USER_LABEL_PREFIX}, if any.", | |
77754180 DK |
926 | tree, (const char *name), |
927 | default_mangle_assembler_name) | |
928 | ||
38f8b050 JR |
929 | HOOK_VECTOR_END (asm_out) |
930 | ||
931 | /* Functions relating to instruction scheduling. All of these | |
e53b6e56 | 932 | default to null pointers, which haifa-sched.cc looks for and handles. */ |
38f8b050 JR |
933 | #undef HOOK_PREFIX |
934 | #define HOOK_PREFIX "TARGET_SCHED_" | |
935 | HOOK_VECTOR (TARGET_SCHED, sched) | |
936 | ||
937 | /* Given the current cost, COST, of an insn, INSN, calculate and | |
938 | return a new cost based on its relationship to DEP_INSN through | |
939 | the dependence LINK. The default is to make no adjustment. */ | |
940 | DEFHOOK | |
941 | (adjust_cost, | |
673c2f63 | 942 | "This function corrects the value of @var{cost} based on the\n\ |
b505225b TS |
943 | relationship between @var{insn} and @var{dep_insn} through a\n\ |
944 | dependence of type dep_type, and strength @var{dw}. It should return the new\n\ | |
945 | value. The default is to make no adjustment to @var{cost}. This can be\n\ | |
946 | used for example to specify to the scheduler using the traditional pipeline\n\ | |
947 | description that an output- or anti-dependence does not incur the same cost\n\ | |
948 | as a data-dependence. If the scheduler using the automaton based pipeline\n\ | |
673c2f63 JM |
949 | description, the cost of anti-dependence is zero and the cost of\n\ |
950 | output-dependence is maximum of one and the difference of latency\n\ | |
951 | times of the first and the second insns. If these values are not\n\ | |
952 | acceptable, you could use the hook to modify them too. See also\n\ | |
953 | @pxref{Processor pipeline description}.", | |
b505225b TS |
954 | int, (rtx_insn *insn, int dep_type1, rtx_insn *dep_insn, int cost, |
955 | unsigned int dw), | |
956 | NULL) | |
38f8b050 JR |
957 | |
958 | /* Adjust the priority of an insn as you see fit. Returns the new priority. */ | |
959 | DEFHOOK | |
960 | (adjust_priority, | |
673c2f63 JM |
961 | "This hook adjusts the integer scheduling priority @var{priority} of\n\ |
962 | @var{insn}. It should return the new priority. Increase the priority to\n\ | |
963 | execute @var{insn} earlier, reduce the priority to execute @var{insn}\n\ | |
964 | later. Do not define this hook if you do not need to adjust the\n\ | |
965 | scheduling priorities of insns.", | |
ac44248e | 966 | int, (rtx_insn *insn, int priority), NULL) |
38f8b050 JR |
967 | |
968 | /* Function which returns the maximum number of insns that can be | |
969 | scheduled in the same machine cycle. This must be constant | |
970 | over an entire compilation. The default is 1. */ | |
971 | DEFHOOK | |
972 | (issue_rate, | |
673c2f63 JM |
973 | "This hook returns the maximum number of instructions that can ever\n\ |
974 | issue at the same time on the target machine. The default is one.\n\ | |
975 | Although the insn scheduler can define itself the possibility of issue\n\ | |
976 | an insn on the same cycle, the value can serve as an additional\n\ | |
977 | constraint to issue insns on the same simulated processor cycle (see\n\ | |
978 | hooks @samp{TARGET_SCHED_REORDER} and @samp{TARGET_SCHED_REORDER2}).\n\ | |
979 | This value must be constant over the entire compilation. If you need\n\ | |
980 | it to vary depending on what the instructions are, you must use\n\ | |
981 | @samp{TARGET_SCHED_VARIABLE_ISSUE}.", | |
38f8b050 JR |
982 | int, (void), NULL) |
983 | ||
984 | /* Calculate how much this insn affects how many more insns we | |
985 | can emit this cycle. Default is they all cost the same. */ | |
986 | DEFHOOK | |
987 | (variable_issue, | |
673c2f63 JM |
988 | "This hook is executed by the scheduler after it has scheduled an insn\n\ |
989 | from the ready list. It should return the number of insns which can\n\ | |
990 | still be issued in the current cycle. The default is\n\ | |
991 | @samp{@w{@var{more} - 1}} for insns other than @code{CLOBBER} and\n\ | |
992 | @code{USE}, which normally are not counted against the issue rate.\n\ | |
993 | You should define this hook if some insns take more machine resources\n\ | |
994 | than others, so that fewer insns can follow them in the same cycle.\n\ | |
995 | @var{file} is either a null pointer, or a stdio stream to write any\n\ | |
996 | debug output to. @var{verbose} is the verbose level provided by\n\ | |
997 | @option{-fsched-verbose-@var{n}}. @var{insn} is the instruction that\n\ | |
998 | was scheduled.", | |
ac44248e | 999 | int, (FILE *file, int verbose, rtx_insn *insn, int more), NULL) |
38f8b050 JR |
1000 | |
1001 | /* Initialize machine-dependent scheduling code. */ | |
1002 | DEFHOOK | |
1003 | (init, | |
673c2f63 JM |
1004 | "This hook is executed by the scheduler at the beginning of each block of\n\ |
1005 | instructions that are to be scheduled. @var{file} is either a null\n\ | |
1006 | pointer, or a stdio stream to write any debug output to. @var{verbose}\n\ | |
1007 | is the verbose level provided by @option{-fsched-verbose-@var{n}}.\n\ | |
1008 | @var{max_ready} is the maximum number of insns in the current scheduling\n\ | |
1009 | region that can be live at the same time. This can be used to allocate\n\ | |
1010 | scratch space if it is needed, e.g.@: by @samp{TARGET_SCHED_REORDER}.", | |
38f8b050 JR |
1011 | void, (FILE *file, int verbose, int max_ready), NULL) |
1012 | ||
1013 | /* Finalize machine-dependent scheduling code. */ | |
1014 | DEFHOOK | |
1015 | (finish, | |
673c2f63 JM |
1016 | "This hook is executed by the scheduler at the end of each block of\n\ |
1017 | instructions that are to be scheduled. It can be used to perform\n\ | |
1018 | cleanup of any actions done by the other scheduling hooks. @var{file}\n\ | |
1019 | is either a null pointer, or a stdio stream to write any debug output\n\ | |
1020 | to. @var{verbose} is the verbose level provided by\n\ | |
1021 | @option{-fsched-verbose-@var{n}}.", | |
38f8b050 JR |
1022 | void, (FILE *file, int verbose), NULL) |
1023 | ||
1024 | /* Initialize machine-dependent function wide scheduling code. */ | |
1025 | DEFHOOK | |
1026 | (init_global, | |
673c2f63 JM |
1027 | "This hook is executed by the scheduler after function level initializations.\n\ |
1028 | @var{file} is either a null pointer, or a stdio stream to write any debug output to.\n\ | |
1029 | @var{verbose} is the verbose level provided by @option{-fsched-verbose-@var{n}}.\n\ | |
1030 | @var{old_max_uid} is the maximum insn uid when scheduling begins.", | |
38f8b050 JR |
1031 | void, (FILE *file, int verbose, int old_max_uid), NULL) |
1032 | ||
1033 | /* Finalize machine-dependent function wide scheduling code. */ | |
1034 | DEFHOOK | |
1035 | (finish_global, | |
673c2f63 JM |
1036 | "This is the cleanup hook corresponding to @code{TARGET_SCHED_INIT_GLOBAL}.\n\ |
1037 | @var{file} is either a null pointer, or a stdio stream to write any debug output to.\n\ | |
1038 | @var{verbose} is the verbose level provided by @option{-fsched-verbose-@var{n}}.", | |
38f8b050 JR |
1039 | void, (FILE *file, int verbose), NULL) |
1040 | ||
1041 | /* Reorder insns in a machine-dependent fashion, in two different | |
1042 | places. Default does nothing. */ | |
1043 | DEFHOOK | |
1044 | (reorder, | |
673c2f63 JM |
1045 | "This hook is executed by the scheduler after it has scheduled the ready\n\ |
1046 | list, to allow the machine description to reorder it (for example to\n\ | |
1047 | combine two small instructions together on @samp{VLIW} machines).\n\ | |
1048 | @var{file} is either a null pointer, or a stdio stream to write any\n\ | |
1049 | debug output to. @var{verbose} is the verbose level provided by\n\ | |
1050 | @option{-fsched-verbose-@var{n}}. @var{ready} is a pointer to the ready\n\ | |
1051 | list of instructions that are ready to be scheduled. @var{n_readyp} is\n\ | |
1052 | a pointer to the number of elements in the ready list. The scheduler\n\ | |
1053 | reads the ready list in reverse order, starting with\n\ | |
1054 | @var{ready}[@var{*n_readyp} @minus{} 1] and going to @var{ready}[0]. @var{clock}\n\ | |
1055 | is the timer tick of the scheduler. You may modify the ready list and\n\ | |
1056 | the number of ready insns. The return value is the number of insns that\n\ | |
1057 | can issue this cycle; normally this is just @code{issue_rate}. See also\n\ | |
1058 | @samp{TARGET_SCHED_REORDER2}.", | |
ce1ce33a | 1059 | int, (FILE *file, int verbose, rtx_insn **ready, int *n_readyp, int clock), NULL) |
38f8b050 JR |
1060 | |
1061 | DEFHOOK | |
1062 | (reorder2, | |
673c2f63 JM |
1063 | "Like @samp{TARGET_SCHED_REORDER}, but called at a different time. That\n\ |
1064 | function is called whenever the scheduler starts a new cycle. This one\n\ | |
1065 | is called once per iteration over a cycle, immediately after\n\ | |
1066 | @samp{TARGET_SCHED_VARIABLE_ISSUE}; it can reorder the ready list and\n\ | |
1067 | return the number of insns to be scheduled in the same cycle. Defining\n\ | |
1068 | this hook can be useful if there are frequent situations where\n\ | |
1069 | scheduling one insn causes other insns to become ready in the same\n\ | |
1070 | cycle. These other insns can then be taken into account properly.", | |
ce1ce33a | 1071 | int, (FILE *file, int verbose, rtx_insn **ready, int *n_readyp, int clock), NULL) |
38f8b050 | 1072 | |
0dc41f28 WM |
1073 | DEFHOOK |
1074 | (macro_fusion_p, | |
1075 | "This hook is used to check whether target platform supports macro fusion.", | |
1076 | bool, (void), NULL) | |
1077 | ||
1078 | DEFHOOK | |
1079 | (macro_fusion_pair_p, | |
892d9879 KT |
1080 | "This hook is used to check whether two insns should be macro fused for\n\ |
1081 | a target microarchitecture. If this hook returns true for the given insn pair\n\ | |
1082 | (@var{prev} and @var{curr}), the scheduler will put them into a sched\n\ | |
1083 | group, and they will not be scheduled apart. The two insns will be either\n\ | |
1084 | two SET insns or a compare and a conditional jump and this hook should\n\ | |
1085 | validate any dependencies needed to fuse the two insns together.", | |
1086 | bool, (rtx_insn *prev, rtx_insn *curr), NULL) | |
0dc41f28 | 1087 | |
38f8b050 JR |
1088 | /* The following member value is a pointer to a function called |
1089 | after evaluation forward dependencies of insns in chain given | |
1090 | by two parameter values (head and tail correspondingly). */ | |
1091 | DEFHOOK | |
1092 | (dependencies_evaluation_hook, | |
673c2f63 JM |
1093 | "This hook is called after evaluation forward dependencies of insns in\n\ |
1094 | chain given by two parameter values (@var{head} and @var{tail}\n\ | |
1095 | correspondingly) but before insns scheduling of the insn chain. For\n\ | |
1096 | example, it can be used for better insn classification if it requires\n\ | |
1097 | analysis of dependencies. This hook can use backward and forward\n\ | |
1098 | dependencies of the insn scheduler because they are already\n\ | |
1099 | calculated.", | |
ce1ce33a | 1100 | void, (rtx_insn *head, rtx_insn *tail), NULL) |
38f8b050 JR |
1101 | |
1102 | /* The values of the following four members are pointers to functions | |
1103 | used to simplify the automaton descriptions. dfa_pre_cycle_insn and | |
1104 | dfa_post_cycle_insn give functions returning insns which are used to | |
1105 | change the pipeline hazard recognizer state when the new simulated | |
1106 | processor cycle correspondingly starts and finishes. The function | |
1107 | defined by init_dfa_pre_cycle_insn and init_dfa_post_cycle_insn are | |
1108 | used to initialize the corresponding insns. The default values of | |
1109 | the members result in not changing the automaton state when the | |
1110 | new simulated processor cycle correspondingly starts and finishes. */ | |
1111 | ||
1112 | DEFHOOK | |
1113 | (init_dfa_pre_cycle_insn, | |
673c2f63 | 1114 | "The hook can be used to initialize data used by the previous hook.", |
38f8b050 JR |
1115 | void, (void), NULL) |
1116 | ||
1117 | DEFHOOK | |
1118 | (dfa_pre_cycle_insn, | |
673c2f63 JM |
1119 | "The hook returns an RTL insn. The automaton state used in the\n\ |
1120 | pipeline hazard recognizer is changed as if the insn were scheduled\n\ | |
1121 | when the new simulated processor cycle starts. Usage of the hook may\n\ | |
1122 | simplify the automaton pipeline description for some @acronym{VLIW}\n\ | |
1123 | processors. If the hook is defined, it is used only for the automaton\n\ | |
1124 | based pipeline description. The default is not to change the state\n\ | |
1125 | when the new simulated processor cycle starts.", | |
38f8b050 JR |
1126 | rtx, (void), NULL) |
1127 | ||
1128 | DEFHOOK | |
1129 | (init_dfa_post_cycle_insn, | |
673c2f63 JM |
1130 | "The hook is analogous to @samp{TARGET_SCHED_INIT_DFA_PRE_CYCLE_INSN} but\n\ |
1131 | used to initialize data used by the previous hook.", | |
38f8b050 JR |
1132 | void, (void), NULL) |
1133 | ||
1134 | DEFHOOK | |
1135 | (dfa_post_cycle_insn, | |
673c2f63 JM |
1136 | "The hook is analogous to @samp{TARGET_SCHED_DFA_PRE_CYCLE_INSN} but used\n\ |
1137 | to changed the state as if the insn were scheduled when the new\n\ | |
1138 | simulated processor cycle finishes.", | |
ac44248e | 1139 | rtx_insn *, (void), NULL) |
38f8b050 JR |
1140 | |
1141 | /* The values of the following two members are pointers to | |
1142 | functions used to simplify the automaton descriptions. | |
1143 | dfa_pre_advance_cycle and dfa_post_advance_cycle are getting called | |
1144 | immediately before and after cycle is advanced. */ | |
1145 | ||
1146 | DEFHOOK | |
1147 | (dfa_pre_advance_cycle, | |
673c2f63 JM |
1148 | "The hook to notify target that the current simulated cycle is about to finish.\n\ |
1149 | The hook is analogous to @samp{TARGET_SCHED_DFA_PRE_CYCLE_INSN} but used\n\ | |
1150 | to change the state in more complicated situations - e.g., when advancing\n\ | |
1151 | state on a single insn is not enough.", | |
38f8b050 JR |
1152 | void, (void), NULL) |
1153 | ||
1154 | DEFHOOK | |
1155 | (dfa_post_advance_cycle, | |
673c2f63 JM |
1156 | "The hook to notify target that new simulated cycle has just started.\n\ |
1157 | The hook is analogous to @samp{TARGET_SCHED_DFA_POST_CYCLE_INSN} but used\n\ | |
1158 | to change the state in more complicated situations - e.g., when advancing\n\ | |
1159 | state on a single insn is not enough.", | |
38f8b050 JR |
1160 | void, (void), NULL) |
1161 | ||
1162 | /* The following member value is a pointer to a function returning value | |
1163 | which defines how many insns in queue `ready' will we try for | |
1164 | multi-pass scheduling. If the member value is nonzero and the | |
1165 | function returns positive value, the DFA based scheduler will make | |
1166 | multi-pass scheduling for the first cycle. In other words, we will | |
1167 | try to choose ready insn which permits to start maximum number of | |
1168 | insns on the same cycle. */ | |
1169 | DEFHOOK | |
1170 | (first_cycle_multipass_dfa_lookahead, | |
673c2f63 JM |
1171 | "This hook controls better choosing an insn from the ready insn queue\n\ |
1172 | for the @acronym{DFA}-based insn scheduler. Usually the scheduler\n\ | |
1173 | chooses the first insn from the queue. If the hook returns a positive\n\ | |
1174 | value, an additional scheduler code tries all permutations of\n\ | |
1175 | @samp{TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD ()}\n\ | |
1176 | subsequent ready insns to choose an insn whose issue will result in\n\ | |
1177 | maximal number of issued insns on the same cycle. For the\n\ | |
1178 | @acronym{VLIW} processor, the code could actually solve the problem of\n\ | |
1179 | packing simple insns into the @acronym{VLIW} insn. Of course, if the\n\ | |
1180 | rules of @acronym{VLIW} packing are described in the automaton.\n\ | |
1181 | \n\ | |
1182 | This code also could be used for superscalar @acronym{RISC}\n\ | |
1183 | processors. Let us consider a superscalar @acronym{RISC} processor\n\ | |
1184 | with 3 pipelines. Some insns can be executed in pipelines @var{A} or\n\ | |
1185 | @var{B}, some insns can be executed only in pipelines @var{B} or\n\ | |
1186 | @var{C}, and one insn can be executed in pipeline @var{B}. The\n\ | |
1187 | processor may issue the 1st insn into @var{A} and the 2nd one into\n\ | |
1188 | @var{B}. In this case, the 3rd insn will wait for freeing @var{B}\n\ | |
1189 | until the next cycle. If the scheduler issues the 3rd insn the first,\n\ | |
1190 | the processor could issue all 3 insns per cycle.\n\ | |
1191 | \n\ | |
1192 | Actually this code demonstrates advantages of the automaton based\n\ | |
1193 | pipeline hazard recognizer. We try quickly and easy many insn\n\ | |
1194 | schedules to choose the best one.\n\ | |
1195 | \n\ | |
1196 | The default is no multipass scheduling.", | |
38f8b050 JR |
1197 | int, (void), NULL) |
1198 | ||
1199 | /* The following member value is pointer to a function controlling | |
1200 | what insns from the ready insn queue will be considered for the | |
1201 | multipass insn scheduling. If the hook returns zero for insn | |
1202 | passed as the parameter, the insn will be not chosen to be issued. */ | |
1203 | DEFHOOK | |
1204 | (first_cycle_multipass_dfa_lookahead_guard, | |
673c2f63 JM |
1205 | "\n\ |
1206 | This hook controls what insns from the ready insn queue will be\n\ | |
1207 | considered for the multipass insn scheduling. If the hook returns\n\ | |
4960a0cb MK |
1208 | zero for @var{insn}, the insn will be considered in multipass scheduling.\n\ |
1209 | Positive return values will remove @var{insn} from consideration on\n\ | |
1210 | the current round of multipass scheduling.\n\ | |
1211 | Negative return values will remove @var{insn} from consideration for given\n\ | |
1212 | number of cycles.\n\ | |
1213 | Backends should be careful about returning non-zero for highest priority\n\ | |
1214 | instruction at position 0 in the ready list. @var{ready_index} is passed\n\ | |
1215 | to allow backends make correct judgements.\n\ | |
673c2f63 JM |
1216 | \n\ |
1217 | The default is that any ready insns can be chosen to be issued.", | |
ac44248e | 1218 | int, (rtx_insn *insn, int ready_index), NULL) |
38f8b050 | 1219 | |
894fd6f2 MK |
1220 | /* This hook prepares the target for a new round of multipass |
1221 | scheduling. | |
1222 | DATA is a pointer to target-specific data used for multipass scheduling. | |
1223 | READY_TRY and N_READY represent the current state of search in the | |
1224 | optimization space. The target can filter out instructions that | |
1225 | should not be tried during current round by setting corresponding | |
1226 | elements in READY_TRY to non-zero. | |
1227 | FIRST_CYCLE_INSN_P is true if this is the first round of multipass | |
1228 | scheduling on current cycle. */ | |
1229 | DEFHOOK | |
1230 | (first_cycle_multipass_begin, | |
673c2f63 JM |
1231 | "This hook prepares the target backend for a new round of multipass\n\ |
1232 | scheduling.", | |
4960a0cb | 1233 | void, (void *data, signed char *ready_try, int n_ready, bool first_cycle_insn_p), |
894fd6f2 MK |
1234 | NULL) |
1235 | ||
1236 | /* This hook is called when multipass scheduling evaluates instruction INSN. | |
1237 | DATA is a pointer to target-specific data that can be used to record effects | |
1238 | of INSN on CPU that are not described in DFA. | |
1239 | READY_TRY and N_READY represent the current state of search in the | |
1240 | optimization space. The target can filter out instructions that | |
073a8998 | 1241 | should not be tried after issuing INSN by setting corresponding |
894fd6f2 MK |
1242 | elements in READY_TRY to non-zero. |
1243 | INSN is the instruction being evaluated. | |
1244 | PREV_DATA is a pointer to target-specific data corresponding | |
073a8998 | 1245 | to a state before issuing INSN. */ |
894fd6f2 MK |
1246 | DEFHOOK |
1247 | (first_cycle_multipass_issue, | |
673c2f63 | 1248 | "This hook is called when multipass scheduling evaluates instruction INSN.", |
ac44248e | 1249 | void, (void *data, signed char *ready_try, int n_ready, rtx_insn *insn, |
894fd6f2 MK |
1250 | const void *prev_data), NULL) |
1251 | ||
1252 | /* This hook is called when multipass scheduling backtracks from evaluation of | |
1253 | instruction corresponding to DATA. | |
1254 | DATA is a pointer to target-specific data that stores the effects | |
1255 | of instruction from which the algorithm backtracks on CPU that are not | |
1256 | described in DFA. | |
1257 | READY_TRY and N_READY represent the current state of search in the | |
1258 | optimization space. The target can filter out instructions that | |
073a8998 | 1259 | should not be tried after issuing INSN by setting corresponding |
894fd6f2 MK |
1260 | elements in READY_TRY to non-zero. */ |
1261 | DEFHOOK | |
1262 | (first_cycle_multipass_backtrack, | |
673c2f63 JM |
1263 | "This is called when multipass scheduling backtracks from evaluation of\n\ |
1264 | an instruction.", | |
4960a0cb | 1265 | void, (const void *data, signed char *ready_try, int n_ready), NULL) |
894fd6f2 MK |
1266 | |
1267 | /* This hook notifies the target about the result of the concluded current | |
1268 | round of multipass scheduling. | |
1269 | DATA is a pointer. | |
1270 | If DATA is non-NULL it points to target-specific data used for multipass | |
1271 | scheduling which corresponds to instruction at the start of the chain of | |
1272 | the winning solution. DATA is NULL when multipass scheduling cannot find | |
1273 | a good enough solution on current cycle and decides to retry later, | |
1274 | usually after advancing the cycle count. */ | |
1275 | DEFHOOK | |
1276 | (first_cycle_multipass_end, | |
673c2f63 JM |
1277 | "This hook notifies the target about the result of the concluded current\n\ |
1278 | round of multipass scheduling.", | |
894fd6f2 MK |
1279 | void, (const void *data), NULL) |
1280 | ||
1281 | /* This hook is called to initialize target-specific data for multipass | |
1282 | scheduling after it has been allocated. | |
1283 | DATA is a pointer to target-specific data that stores the effects | |
1284 | of instruction from which the algorithm backtracks on CPU that are not | |
1285 | described in DFA. */ | |
1286 | DEFHOOK | |
1287 | (first_cycle_multipass_init, | |
673c2f63 | 1288 | "This hook initializes target-specific data used in multipass scheduling.", |
894fd6f2 MK |
1289 | void, (void *data), NULL) |
1290 | ||
1291 | /* This hook is called to finalize target-specific data for multipass | |
1292 | scheduling before it is deallocated. | |
1293 | DATA is a pointer to target-specific data that stores the effects | |
1294 | of instruction from which the algorithm backtracks on CPU that are not | |
1295 | described in DFA. */ | |
1296 | DEFHOOK | |
1297 | (first_cycle_multipass_fini, | |
673c2f63 | 1298 | "This hook finalizes target-specific data used in multipass scheduling.", |
894fd6f2 MK |
1299 | void, (void *data), NULL) |
1300 | ||
38f8b050 JR |
1301 | /* The following member value is pointer to a function called by |
1302 | the insn scheduler before issuing insn passed as the third | |
1303 | parameter on given cycle. If the hook returns nonzero, the | |
1304 | insn is not issued on given processors cycle. Instead of that, | |
1305 | the processor cycle is advanced. If the value passed through | |
1306 | the last parameter is zero, the insn ready queue is not sorted | |
1307 | on the new cycle start as usually. The first parameter passes | |
1308 | file for debugging output. The second one passes the scheduler | |
1309 | verbose level of the debugging output. The forth and the fifth | |
1310 | parameter values are correspondingly processor cycle on which | |
1311 | the previous insn has been issued and the current processor cycle. */ | |
c06bbdf7 | 1312 | DEFHOOK |
38f8b050 | 1313 | (dfa_new_cycle, |
673c2f63 JM |
1314 | "This hook is called by the insn scheduler before issuing @var{insn}\n\ |
1315 | on cycle @var{clock}. If the hook returns nonzero,\n\ | |
1316 | @var{insn} is not issued on this processor cycle. Instead,\n\ | |
1317 | the processor cycle is advanced. If *@var{sort_p}\n\ | |
1318 | is zero, the insn ready queue is not sorted on the new cycle\n\ | |
1319 | start as usually. @var{dump} and @var{verbose} specify the file and\n\ | |
1320 | verbosity level to use for debugging output.\n\ | |
1321 | @var{last_clock} and @var{clock} are, respectively, the\n\ | |
1322 | processor cycle on which the previous insn has been issued,\n\ | |
1323 | and the current processor cycle.", | |
ac44248e | 1324 | int, (FILE *dump, int verbose, rtx_insn *insn, int last_clock, |
c06bbdf7 | 1325 | int clock, int *sort_p), |
38f8b050 JR |
1326 | NULL) |
1327 | ||
1328 | /* The following member value is a pointer to a function called by the | |
1329 | insn scheduler. It should return true if there exists a dependence | |
1330 | which is considered costly by the target, between the insn | |
1331 | DEP_PRO (&_DEP), and the insn DEP_CON (&_DEP). The first parameter is | |
1332 | the dep that represents the dependence between the two insns. The | |
1333 | second argument is the cost of the dependence as estimated by | |
1334 | the scheduler. The last argument is the distance in cycles | |
1335 | between the already scheduled insn (first parameter) and the | |
1336 | second insn (second parameter). */ | |
1337 | DEFHOOK | |
1338 | (is_costly_dependence, | |
673c2f63 JM |
1339 | "This hook is used to define which dependences are considered costly by\n\ |
1340 | the target, so costly that it is not advisable to schedule the insns that\n\ | |
1341 | are involved in the dependence too close to one another. The parameters\n\ | |
1342 | to this hook are as follows: The first parameter @var{_dep} is the dependence\n\ | |
1343 | being evaluated. The second parameter @var{cost} is the cost of the\n\ | |
1344 | dependence as estimated by the scheduler, and the third\n\ | |
1345 | parameter @var{distance} is the distance in cycles between the two insns.\n\ | |
1346 | The hook returns @code{true} if considering the distance between the two\n\ | |
1347 | insns the dependence between them is considered costly by the target,\n\ | |
1348 | and @code{false} otherwise.\n\ | |
1349 | \n\ | |
1350 | Defining this hook can be useful in multiple-issue out-of-order machines,\n\ | |
1351 | where (a) it's practically hopeless to predict the actual data/resource\n\ | |
1352 | delays, however: (b) there's a better chance to predict the actual grouping\n\ | |
1353 | that will be formed, and (c) correctly emulating the grouping can be very\n\ | |
1354 | important. In such targets one may want to allow issuing dependent insns\n\ | |
1355 | closer to one another---i.e., closer than the dependence distance; however,\n\ | |
1356 | not in cases of ``costly dependences'', which this hooks allows to define.", | |
38f8b050 JR |
1357 | bool, (struct _dep *_dep, int cost, int distance), NULL) |
1358 | ||
38f8b050 JR |
1359 | /* The following member value is a pointer to a function called |
1360 | by the insn scheduler. This hook is called to notify the backend | |
1361 | that new instructions were emitted. */ | |
1362 | DEFHOOK | |
1363 | (h_i_d_extended, | |
673c2f63 JM |
1364 | "This hook is called by the insn scheduler after emitting a new instruction to\n\ |
1365 | the instruction stream. The hook notifies a target backend to extend its\n\ | |
1366 | per instruction data structures.", | |
38f8b050 JR |
1367 | void, (void), NULL) |
1368 | ||
1369 | /* Next 5 functions are for multi-point scheduling. */ | |
1370 | ||
1371 | /* Allocate memory for scheduler context. */ | |
1372 | DEFHOOK | |
1373 | (alloc_sched_context, | |
673c2f63 | 1374 | "Return a pointer to a store large enough to hold target scheduling context.", |
38f8b050 JR |
1375 | void *, (void), NULL) |
1376 | ||
1377 | /* Fills the context from the local machine scheduler context. */ | |
1378 | DEFHOOK | |
1379 | (init_sched_context, | |
673c2f63 JM |
1380 | "Initialize store pointed to by @var{tc} to hold target scheduling context.\n\ |
1381 | It @var{clean_p} is true then initialize @var{tc} as if scheduler is at the\n\ | |
1382 | beginning of the block. Otherwise, copy the current context into @var{tc}.", | |
38f8b050 JR |
1383 | void, (void *tc, bool clean_p), NULL) |
1384 | ||
1385 | /* Sets local machine scheduler context to a saved value. */ | |
1386 | DEFHOOK | |
1387 | (set_sched_context, | |
673c2f63 | 1388 | "Copy target scheduling context pointed to by @var{tc} to the current context.", |
38f8b050 JR |
1389 | void, (void *tc), NULL) |
1390 | ||
1391 | /* Clears a scheduler context so it becomes like after init. */ | |
1392 | DEFHOOK | |
1393 | (clear_sched_context, | |
673c2f63 | 1394 | "Deallocate internal data in target scheduling context pointed to by @var{tc}.", |
38f8b050 JR |
1395 | void, (void *tc), NULL) |
1396 | ||
1397 | /* Frees the scheduler context. */ | |
1398 | DEFHOOK | |
1399 | (free_sched_context, | |
673c2f63 | 1400 | "Deallocate a store for target scheduling context pointed to by @var{tc}.", |
38f8b050 JR |
1401 | void, (void *tc), NULL) |
1402 | ||
1403 | /* The following member value is a pointer to a function called | |
1404 | by the insn scheduler. | |
1405 | The first parameter is an instruction, the second parameter is the type | |
1406 | of the requested speculation, and the third parameter is a pointer to the | |
1407 | speculative pattern of the corresponding type (set if return value == 1). | |
1408 | It should return | |
1409 | -1, if there is no pattern, that will satisfy the requested speculation type, | |
1410 | 0, if current pattern satisfies the requested speculation type, | |
1411 | 1, if pattern of the instruction should be changed to the newly | |
1412 | generated one. */ | |
1413 | DEFHOOK | |
1414 | (speculate_insn, | |
673c2f63 JM |
1415 | "This hook is called by the insn scheduler when @var{insn} has only\n\ |
1416 | speculative dependencies and therefore can be scheduled speculatively.\n\ | |
1417 | The hook is used to check if the pattern of @var{insn} has a speculative\n\ | |
1418 | version and, in case of successful check, to generate that speculative\n\ | |
1419 | pattern. The hook should return 1, if the instruction has a speculative form,\n\ | |
1420 | or @minus{}1, if it doesn't. @var{request} describes the type of requested\n\ | |
1421 | speculation. If the return value equals 1 then @var{new_pat} is assigned\n\ | |
1422 | the generated speculative pattern.", | |
ac44248e | 1423 | int, (rtx_insn *insn, unsigned int dep_status, rtx *new_pat), NULL) |
38f8b050 JR |
1424 | |
1425 | /* The following member value is a pointer to a function called | |
1426 | by the insn scheduler. It should return true if the check instruction | |
1427 | passed as the parameter needs a recovery block. */ | |
1428 | DEFHOOK | |
1429 | (needs_block_p, | |
673c2f63 JM |
1430 | "This hook is called by the insn scheduler during generation of recovery code\n\ |
1431 | for @var{insn}. It should return @code{true}, if the corresponding check\n\ | |
1432 | instruction should branch to recovery code, or @code{false} otherwise.", | |
8e90de43 | 1433 | bool, (unsigned int dep_status), NULL) |
38f8b050 JR |
1434 | |
1435 | /* The following member value is a pointer to a function called | |
1436 | by the insn scheduler. It should return a pattern for the check | |
1437 | instruction. | |
1438 | The first parameter is a speculative instruction, the second parameter | |
1439 | is the label of the corresponding recovery block (or null, if it is a | |
8e90de43 SB |
1440 | simple check). The third parameter is the kind of speculation that |
1441 | is being performed. */ | |
38f8b050 JR |
1442 | DEFHOOK |
1443 | (gen_spec_check, | |
673c2f63 JM |
1444 | "This hook is called by the insn scheduler to generate a pattern for recovery\n\ |
1445 | check instruction. If @var{mutate_p} is zero, then @var{insn} is a\n\ | |
1446 | speculative instruction for which the check should be generated.\n\ | |
1447 | @var{label} is either a label of a basic block, where recovery code should\n\ | |
1448 | be emitted, or a null pointer, when requested check doesn't branch to\n\ | |
1449 | recovery code (a simple check). If @var{mutate_p} is nonzero, then\n\ | |
1450 | a pattern for a branchy check corresponding to a simple check denoted by\n\ | |
1451 | @var{insn} should be generated. In this case @var{label} can't be null.", | |
ac44248e | 1452 | rtx, (rtx_insn *insn, rtx_insn *label, unsigned int ds), NULL) |
38f8b050 | 1453 | |
38f8b050 JR |
1454 | /* The following member value is a pointer to a function that provides |
1455 | information about the speculation capabilities of the target. | |
1456 | The parameter is a pointer to spec_info variable. */ | |
1457 | DEFHOOK | |
1458 | (set_sched_flags, | |
673c2f63 JM |
1459 | "This hook is used by the insn scheduler to find out what features should be\n\ |
1460 | enabled/used.\n\ | |
1461 | The structure *@var{spec_info} should be filled in by the target.\n\ | |
1462 | The structure describes speculation types that can be used in the scheduler.", | |
38f8b050 JR |
1463 | void, (struct spec_info_def *spec_info), NULL) |
1464 | ||
1465 | DEFHOOK_UNDOC | |
1466 | (get_insn_spec_ds, | |
1467 | "Return speculation types of instruction @var{insn}.", | |
ac44248e | 1468 | unsigned int, (rtx_insn *insn), NULL) |
38f8b050 JR |
1469 | |
1470 | DEFHOOK_UNDOC | |
1471 | (get_insn_checked_ds, | |
1472 | "Return speculation types that are checked for instruction @var{insn}", | |
ac44248e | 1473 | unsigned int, (rtx_insn *insn), NULL) |
38f8b050 | 1474 | |
176274c9 SB |
1475 | DEFHOOK |
1476 | (can_speculate_insn, | |
1477 | "Some instructions should never be speculated by the schedulers, usually\n\ | |
1478 | because the instruction is too expensive to get this wrong. Often such\n\ | |
1479 | instructions have long latency, and often they are not fully modeled in the\n\ | |
1480 | pipeline descriptions. This hook should return @code{false} if @var{insn}\n\ | |
1481 | should not be speculated.", | |
1482 | bool, (rtx_insn *insn), hook_bool_rtx_insn_true) | |
1483 | ||
38f8b050 JR |
1484 | DEFHOOK_UNDOC |
1485 | (skip_rtx_p, | |
1486 | "Return bool if rtx scanning should just skip current layer and\ | |
1487 | advance to the inner rtxes.", | |
1488 | bool, (const_rtx x), NULL) | |
1489 | ||
1490 | /* The following member value is a pointer to a function that provides | |
1491 | information about the target resource-based lower bound which is | |
1492 | used by the swing modulo scheduler. The parameter is a pointer | |
1493 | to ddg variable. */ | |
1494 | DEFHOOK | |
1495 | (sms_res_mii, | |
673c2f63 JM |
1496 | "This hook is called by the swing modulo scheduler to calculate a\n\ |
1497 | resource-based lower bound which is based on the resources available in\n\ | |
1498 | the machine and the resources required by each instruction. The target\n\ | |
1499 | backend can use @var{g} to calculate such bound. A very simple lower\n\ | |
1500 | bound will be used in case this hook is not implemented: the total number\n\ | |
1501 | of instructions divided by the issue rate.", | |
38f8b050 JR |
1502 | int, (struct ddg *g), NULL) |
1503 | ||
7942e47e RY |
1504 | /* The following member value is a function that initializes dispatch |
1505 | schedling and adds instructions to dispatch window according to its | |
1506 | parameters. */ | |
1507 | DEFHOOK | |
1508 | (dispatch_do, | |
673c2f63 JM |
1509 | "This hook is called by Haifa Scheduler. It performs the operation specified\n\ |
1510 | in its second parameter.", | |
ac44248e DM |
1511 | void, (rtx_insn *insn, int x), |
1512 | hook_void_rtx_insn_int) | |
7942e47e | 1513 | |
700d4cb0 | 1514 | /* The following member value is a function that returns true is |
7942e47e RY |
1515 | dispatch schedling is supported in hardware and condition passed |
1516 | as the second parameter is true. */ | |
1517 | DEFHOOK | |
1518 | (dispatch, | |
673c2f63 JM |
1519 | "This hook is called by Haifa Scheduler. It returns true if dispatch scheduling\n\ |
1520 | is supported in hardware and the condition specified in the parameter is true.", | |
ac44248e DM |
1521 | bool, (rtx_insn *insn, int x), |
1522 | hook_bool_rtx_insn_int_false) | |
7942e47e | 1523 | |
b0bd15f7 BS |
1524 | DEFHOOKPOD |
1525 | (exposed_pipeline, | |
1526 | "True if the processor has an exposed pipeline, which means that not just\n\ | |
1527 | the order of instructions is important for correctness when scheduling, but\n\ | |
1528 | also the latencies of operations.", | |
1529 | bool, false) | |
1530 | ||
df7b0cc4 EI |
1531 | /* The following member value is a function that returns number |
1532 | of operations reassociator should try to put in parallel for | |
1533 | statements of the given type. By default 1 is used. */ | |
1534 | DEFHOOK | |
1535 | (reassociation_width, | |
1536 | "This hook is called by tree reassociator to determine a level of\n\ | |
1537 | parallelism required in output calculations chain.", | |
ef4bddc2 | 1538 | int, (unsigned int opc, machine_mode mode), |
df7b0cc4 EI |
1539 | hook_int_uint_mode_1) |
1540 | ||
b16abbcb BC |
1541 | /* The following member value is a function that returns priority for |
1542 | fusion of each instruction via pointer parameters. */ | |
1543 | DEFHOOK | |
1544 | (fusion_priority, | |
1545 | "This hook is called by scheduling fusion pass. It calculates fusion\n\ | |
1546 | priorities for each instruction passed in by parameter. The priorities\n\ | |
1547 | are returned via pointer parameters.\n\ | |
1548 | \n\ | |
1549 | @var{insn} is the instruction whose priorities need to be calculated.\n\ | |
1550 | @var{max_pri} is the maximum priority can be returned in any cases.\n\ | |
1551 | @var{fusion_pri} is the pointer parameter through which @var{insn}'s\n\ | |
1552 | fusion priority should be calculated and returned.\n\ | |
1553 | @var{pri} is the pointer parameter through which @var{insn}'s priority\n\ | |
1554 | should be calculated and returned.\n\ | |
1555 | \n\ | |
1556 | Same @var{fusion_pri} should be returned for instructions which should\n\ | |
1557 | be scheduled together. Different @var{pri} should be returned for\n\ | |
1558 | instructions with same @var{fusion_pri}. @var{fusion_pri} is the major\n\ | |
1559 | sort key, @var{pri} is the minor sort key. All instructions will be\n\ | |
1560 | scheduled according to the two priorities. All priorities calculated\n\ | |
1561 | should be between 0 (exclusive) and @var{max_pri} (inclusive). To avoid\n\ | |
1562 | false dependencies, @var{fusion_pri} of instructions which need to be\n\ | |
1563 | scheduled together should be smaller than @var{fusion_pri} of irrelevant\n\ | |
1564 | instructions.\n\ | |
1565 | \n\ | |
1566 | Given below example:\n\ | |
1567 | \n\ | |
51be4977 | 1568 | @smallexample\n\ |
b16abbcb BC |
1569 | ldr r10, [r1, 4]\n\ |
1570 | add r4, r4, r10\n\ | |
1571 | ldr r15, [r2, 8]\n\ | |
1572 | sub r5, r5, r15\n\ | |
1573 | ldr r11, [r1, 0]\n\ | |
1574 | add r4, r4, r11\n\ | |
1575 | ldr r16, [r2, 12]\n\ | |
1576 | sub r5, r5, r16\n\ | |
51be4977 | 1577 | @end smallexample\n\ |
b16abbcb BC |
1578 | \n\ |
1579 | On targets like ARM/AArch64, the two pairs of consecutive loads should be\n\ | |
1580 | merged. Since peephole2 pass can't help in this case unless consecutive\n\ | |
1581 | loads are actually next to each other in instruction flow. That's where\n\ | |
1582 | this scheduling fusion pass works. This hook calculates priority for each\n\ | |
1583 | instruction based on its fustion type, like:\n\ | |
1584 | \n\ | |
51be4977 BC |
1585 | @smallexample\n\ |
1586 | ldr r10, [r1, 4] ; fusion_pri=99, pri=96\n\ | |
1587 | add r4, r4, r10 ; fusion_pri=100, pri=100\n\ | |
1588 | ldr r15, [r2, 8] ; fusion_pri=98, pri=92\n\ | |
1589 | sub r5, r5, r15 ; fusion_pri=100, pri=100\n\ | |
1590 | ldr r11, [r1, 0] ; fusion_pri=99, pri=100\n\ | |
1591 | add r4, r4, r11 ; fusion_pri=100, pri=100\n\ | |
1592 | ldr r16, [r2, 12] ; fusion_pri=98, pri=88\n\ | |
1593 | sub r5, r5, r16 ; fusion_pri=100, pri=100\n\ | |
1594 | @end smallexample\n\ | |
b16abbcb BC |
1595 | \n\ |
1596 | Scheduling fusion pass then sorts all ready to issue instructions according\n\ | |
1597 | to the priorities. As a result, instructions of same fusion type will be\n\ | |
1598 | pushed together in instruction flow, like:\n\ | |
1599 | \n\ | |
51be4977 | 1600 | @smallexample\n\ |
b16abbcb BC |
1601 | ldr r11, [r1, 0]\n\ |
1602 | ldr r10, [r1, 4]\n\ | |
1603 | ldr r15, [r2, 8]\n\ | |
1604 | ldr r16, [r2, 12]\n\ | |
1605 | add r4, r4, r10\n\ | |
1606 | sub r5, r5, r15\n\ | |
1607 | add r4, r4, r11\n\ | |
1608 | sub r5, r5, r16\n\ | |
51be4977 | 1609 | @end smallexample\n\ |
b16abbcb BC |
1610 | \n\ |
1611 | Now peephole2 pass can simply merge the two pairs of loads.\n\ | |
1612 | \n\ | |
1613 | Since scheduling fusion pass relies on peephole2 to do real fusion\n\ | |
1614 | work, it is only enabled by default when peephole2 is in effect.\n\ | |
1615 | \n\ | |
1616 | This is firstly introduced on ARM/AArch64 targets, please refer to\n\ | |
1617 | the hook implementation for how different fusion types are supported.", | |
1618 | void, (rtx_insn *insn, int max_pri, int *fusion_pri, int *pri), NULL) | |
1619 | ||
38f8b050 JR |
1620 | HOOK_VECTOR_END (sched) |
1621 | ||
e76c7157 | 1622 | /* Functions relating to OpenMP SIMD and __attribute__((simd)) clones. */ |
0136f8f0 AH |
1623 | #undef HOOK_PREFIX |
1624 | #define HOOK_PREFIX "TARGET_SIMD_CLONE_" | |
1625 | HOOK_VECTOR (TARGET_SIMD_CLONE, simd_clone) | |
1626 | ||
1627 | DEFHOOK | |
1628 | (compute_vecsize_and_simdlen, | |
1629 | "This hook should set @var{vecsize_mangle}, @var{vecsize_int}, @var{vecsize_float}\n\ | |
1630 | fields in @var{simd_clone} structure pointed by @var{clone_info} argument and also\n\ | |
1631 | @var{simdlen} field if it was previously 0.\n\ | |
1632 | The hook should return 0 if SIMD clones shouldn't be emitted,\n\ | |
1633 | or number of @var{vecsize_mangle} variants that should be emitted.", | |
1634 | int, (struct cgraph_node *, struct cgraph_simd_clone *, tree, int), NULL) | |
1635 | ||
1636 | DEFHOOK | |
1637 | (adjust, | |
1638 | "This hook should add implicit @code{attribute(target(\"...\"))} attribute\n\ | |
1639 | to SIMD clone @var{node} if needed.", | |
1640 | void, (struct cgraph_node *), NULL) | |
1641 | ||
1642 | DEFHOOK | |
1643 | (usable, | |
1644 | "This hook should return -1 if SIMD clone @var{node} shouldn't be used\n\ | |
1645 | in vectorized loops in current function, or non-negative number if it is\n\ | |
1646 | usable. In that case, the smaller the number is, the more desirable it is\n\ | |
1647 | to use it.", | |
1648 | int, (struct cgraph_node *), NULL) | |
1649 | ||
1650 | HOOK_VECTOR_END (simd_clone) | |
1651 | ||
5012919d AM |
1652 | /* Functions relating to OpenMP SIMT vectorization transform. */ |
1653 | #undef HOOK_PREFIX | |
1654 | #define HOOK_PREFIX "TARGET_SIMT_" | |
1655 | HOOK_VECTOR (TARGET_SIMT, simt) | |
1656 | ||
1657 | DEFHOOK | |
1658 | (vf, | |
1659 | "Return number of threads in SIMT thread group on the target.", | |
1660 | int, (void), NULL) | |
1661 | ||
1662 | HOOK_VECTOR_END (simt) | |
1663 | ||
9ba66bf5 JJ |
1664 | /* Functions relating to OpenMP. */ |
1665 | #undef HOOK_PREFIX | |
1666 | #define HOOK_PREFIX "TARGET_OMP_" | |
1667 | HOOK_VECTOR (TARGET_OMP, omp) | |
1668 | ||
1669 | DEFHOOK | |
1670 | (device_kind_arch_isa, | |
1671 | "Return 1 if @var{trait} @var{name} is present in the OpenMP context's\n\ | |
1672 | device trait set, return 0 if not present in any OpenMP context in the\n\ | |
1673 | whole translation unit, or -1 if not present in the current OpenMP context\n\ | |
1674 | but might be present in another OpenMP context in the same TU.", | |
1675 | int, (enum omp_device_kind_arch_isa trait, const char *name), NULL) | |
1676 | ||
1677 | HOOK_VECTOR_END (omp) | |
1678 | ||
94829f87 NS |
1679 | /* Functions relating to openacc. */ |
1680 | #undef HOOK_PREFIX | |
1681 | #define HOOK_PREFIX "TARGET_GOACC_" | |
1682 | HOOK_VECTOR (TARGET_GOACC, goacc) | |
1683 | ||
1684 | DEFHOOK | |
1685 | (validate_dims, | |
1686 | "This hook should check the launch dimensions provided for an OpenACC\n\ | |
1687 | compute region, or routine. Defaulted values are represented as -1\n\ | |
b6adbb9f | 1688 | and non-constant values as 0. The @var{fn_level} is negative for the\n\ |
700d4cb0 | 1689 | function corresponding to the compute region. For a routine it is the\n\ |
b6adbb9f NS |
1690 | outermost level at which partitioned execution may be spawned. The hook\n\ |
1691 | should verify non-default values. If DECL is NULL, global defaults\n\ | |
1692 | are being validated and unspecified defaults should be filled in.\n\ | |
1693 | Diagnostics should be issued as appropriate. Return\n\ | |
94829f87 NS |
1694 | true, if changes have been made. You must override this hook to\n\ |
1695 | provide dimensions larger than 1.", | |
46dedae6 | 1696 | bool, (tree decl, int *dims, int fn_level, unsigned used), |
94829f87 NS |
1697 | default_goacc_validate_dims) |
1698 | ||
bd751975 NS |
1699 | DEFHOOK |
1700 | (dim_limit, | |
1701 | "This hook should return the maximum size of a particular dimension,\n\ | |
1702 | or zero if unbounded.", | |
1703 | int, (int axis), | |
1704 | default_goacc_dim_limit) | |
1705 | ||
6e91acf8 NS |
1706 | DEFHOOK |
1707 | (fork_join, | |
9bd46bc9 NS |
1708 | "This hook can be used to convert IFN_GOACC_FORK and IFN_GOACC_JOIN\n\ |
1709 | function calls to target-specific gimple, or indicate whether they\n\ | |
1710 | should be retained. It is executed during the oacc_device_lower pass.\n\ | |
1711 | It should return true, if the call should be retained. It should\n\ | |
1712 | return false, if it is to be deleted (either because target-specific\n\ | |
1713 | gimple has been inserted before it, or there is no need for it).\n\ | |
1714 | The default hook returns false, if there are no RTL expanders for them.", | |
6e91acf8 NS |
1715 | bool, (gcall *call, const int *dims, bool is_fork), |
1716 | default_goacc_fork_join) | |
1717 | ||
e5014671 NS |
1718 | DEFHOOK |
1719 | (reduction, | |
1720 | "This hook is used by the oacc_transform pass to expand calls to the\n\ | |
1721 | @var{GOACC_REDUCTION} internal function, into a sequence of gimple\n\ | |
1722 | instructions. @var{call} is gimple statement containing the call to\n\ | |
1723 | the function. This hook removes statement @var{call} after the\n\ | |
1724 | expanded sequence has been inserted. This hook is also responsible\n\ | |
1725 | for allocating any storage for reductions when necessary.", | |
1726 | void, (gcall *call), | |
1727 | default_goacc_reduction) | |
1728 | ||
29a2f518 JB |
1729 | DEFHOOK |
1730 | (adjust_private_decl, | |
1731 | "This hook, if defined, is used by accelerator target back-ends to adjust\n\ | |
1732 | OpenACC variable declarations that should be made private to the given\n\ | |
1733 | parallelism level (i.e. @code{GOMP_DIM_GANG}, @code{GOMP_DIM_WORKER} or\n\ | |
1734 | @code{GOMP_DIM_VECTOR}). A typical use for this hook is to force variable\n\ | |
1735 | declarations at the @code{gang} level to reside in GPU shared memory.\n\ | |
11b8286a | 1736 | @var{loc} may be used for diagnostic purposes.\n\ |
29a2f518 JB |
1737 | \n\ |
1738 | You may also use the @code{TARGET_GOACC_EXPAND_VAR_DECL} hook if the\n\ | |
1739 | adjusted variable declaration needs to be expanded to RTL in a non-standard\n\ | |
1740 | way.", | |
11b8286a | 1741 | tree, (location_t loc, tree var, int level), |
29a2f518 JB |
1742 | NULL) |
1743 | ||
1744 | DEFHOOK | |
1745 | (expand_var_decl, | |
1746 | "This hook, if defined, is used by accelerator target back-ends to expand\n\ | |
1747 | specially handled kinds of @code{VAR_DECL} expressions. A particular use is\n\ | |
1748 | to place variables with specific attributes inside special accelarator\n\ | |
1749 | memories. A return value of @code{NULL} indicates that the target does not\n\ | |
1750 | handle this @code{VAR_DECL}, and normal RTL expanding is resumed.\n\ | |
1751 | \n\ | |
1752 | Only define this hook if your accelerator target needs to expand certain\n\ | |
1753 | @code{VAR_DECL} nodes in a way that differs from the default. You can also adjust\n\ | |
1754 | private variables at OpenACC device-lowering time using the\n\ | |
1755 | @code{TARGET_GOACC_ADJUST_PRIVATE_DECL} target hook.", | |
1756 | rtx, (tree var), | |
1757 | NULL) | |
1758 | ||
e2a58ed6 JB |
1759 | DEFHOOK |
1760 | (create_worker_broadcast_record, | |
1761 | "Create a record used to propagate local-variable state from an active\n\ | |
1762 | worker to other workers. A possible implementation might adjust the type\n\ | |
1763 | of REC to place the new variable in shared GPU memory.\n\ | |
1764 | \n\ | |
1765 | Presence of this target hook indicates that middle end neutering/broadcasting\n\ | |
1766 | be used.", | |
2a3f9f65 JB |
1767 | tree, (tree rec, bool sender, const char *name, unsigned HOST_WIDE_INT offset), |
1768 | NULL) | |
1769 | ||
1770 | DEFHOOK | |
1771 | (shared_mem_layout, | |
1772 | "Lay out a fixed shared-memory region on the target. The LO and HI\n\ | |
1773 | arguments should be set to a range of addresses that can be used for worker\n\ | |
1774 | broadcasting. The dimensions, reduction size and gang-private size\n\ | |
1775 | arguments are for the current offload region.", | |
1776 | void, (unsigned HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, int[], | |
1777 | unsigned HOST_WIDE_INT[], unsigned HOST_WIDE_INT[]), | |
e2a58ed6 JB |
1778 | NULL) |
1779 | ||
94829f87 NS |
1780 | HOOK_VECTOR_END (goacc) |
1781 | ||
38f8b050 JR |
1782 | /* Functions relating to vectorization. */ |
1783 | #undef HOOK_PREFIX | |
1784 | #define HOOK_PREFIX "TARGET_VECTORIZE_" | |
1785 | HOOK_VECTOR (TARGET_VECTORIZE, vectorize) | |
1786 | ||
1787 | /* The following member value is a pointer to a function called | |
1788 | by the vectorizer, and return the decl of the target builtin | |
1789 | function. */ | |
1790 | DEFHOOK | |
1791 | (builtin_mask_for_load, | |
673c2f63 JM |
1792 | "This hook should return the DECL of a function @var{f} that given an\n\ |
1793 | address @var{addr} as an argument returns a mask @var{m} that can be\n\ | |
1794 | used to extract from two vectors the relevant data that resides in\n\ | |
1795 | @var{addr} in case @var{addr} is not properly aligned.\n\ | |
1796 | \n\ | |
1797 | The autovectorizer, when vectorizing a load operation from an address\n\ | |
1798 | @var{addr} that may be unaligned, will generate two vector loads from\n\ | |
1799 | the two aligned addresses around @var{addr}. It then generates a\n\ | |
1800 | @code{REALIGN_LOAD} operation to extract the relevant data from the\n\ | |
1801 | two loaded vectors. The first two arguments to @code{REALIGN_LOAD},\n\ | |
1802 | @var{v1} and @var{v2}, are the two vectors, each of size @var{VS}, and\n\ | |
1803 | the third argument, @var{OFF}, defines how the data will be extracted\n\ | |
1804 | from these two vectors: if @var{OFF} is 0, then the returned vector is\n\ | |
1805 | @var{v2}; otherwise, the returned vector is composed from the last\n\ | |
1806 | @var{VS}-@var{OFF} elements of @var{v1} concatenated to the first\n\ | |
1807 | @var{OFF} elements of @var{v2}.\n\ | |
1808 | \n\ | |
1809 | If this hook is defined, the autovectorizer will generate a call\n\ | |
1810 | to @var{f} (using the DECL tree that this hook returns) and will\n\ | |
1811 | use the return value of @var{f} as the argument @var{OFF} to\n\ | |
1812 | @code{REALIGN_LOAD}. Therefore, the mask @var{m} returned by @var{f}\n\ | |
1813 | should comply with the semantics expected by @code{REALIGN_LOAD}\n\ | |
1814 | described above.\n\ | |
1815 | If this hook is not defined, then @var{addr} will be used as\n\ | |
1816 | the argument @var{OFF} to @code{REALIGN_LOAD}, in which case the low\n\ | |
1817 | log2(@var{VS}) @minus{} 1 bits of @var{addr} will be considered.", | |
38f8b050 JR |
1818 | tree, (void), NULL) |
1819 | ||
10766209 RS |
1820 | /* Returns a built-in function that realizes the vectorized version of |
1821 | a target-independent function, or NULL_TREE if not available. */ | |
38f8b050 JR |
1822 | DEFHOOK |
1823 | (builtin_vectorized_function, | |
673c2f63 | 1824 | "This hook should return the decl of a function that implements the\n\ |
10766209 | 1825 | vectorized variant of the function with the @code{combined_fn} code\n\ |
673c2f63 | 1826 | @var{code} or @code{NULL_TREE} if such a function is not available.\n\ |
10766209 RS |
1827 | The return type of the vectorized function shall be of vector type\n\ |
1828 | @var{vec_type_out} and the argument types should be @var{vec_type_in}.", | |
1829 | tree, (unsigned code, tree vec_type_out, tree vec_type_in), | |
1830 | default_builtin_vectorized_function) | |
1831 | ||
1832 | /* Returns a built-in function that realizes the vectorized version of | |
1833 | a target-specific function, or NULL_TREE if not available. */ | |
1834 | DEFHOOK | |
1835 | (builtin_md_vectorized_function, | |
1836 | "This hook should return the decl of a function that implements the\n\ | |
1837 | vectorized variant of target built-in function @code{fndecl}. The\n\ | |
673c2f63 JM |
1838 | return type of the vectorized function shall be of vector type\n\ |
1839 | @var{vec_type_out} and the argument types should be @var{vec_type_in}.", | |
38f8b050 | 1840 | tree, (tree fndecl, tree vec_type_out, tree vec_type_in), |
10766209 | 1841 | default_builtin_md_vectorized_function) |
38f8b050 | 1842 | |
720f5239 IR |
1843 | /* Cost of different vector/scalar statements in vectorization cost |
1844 | model. In case of misaligned vector loads and stores the cost depends | |
1845 | on the data type and misalignment value. */ | |
38f8b050 JR |
1846 | DEFHOOK |
1847 | (builtin_vectorization_cost, | |
673c2f63 JM |
1848 | "Returns cost of different scalar or vector statements for vectorization cost model.\n\ |
1849 | For vector memory operations the cost may depend on type (@var{vectype}) and\n\ | |
1850 | misalignment value (@var{misalign}).", | |
720f5239 | 1851 | int, (enum vect_cost_for_stmt type_of_cost, tree vectype, int misalign), |
38f8b050 JR |
1852 | default_builtin_vectorization_cost) |
1853 | ||
f702e7d4 RS |
1854 | DEFHOOK |
1855 | (preferred_vector_alignment, | |
1856 | "This hook returns the preferred alignment in bits for accesses to\n\ | |
1857 | vectors of type @var{type} in vectorized code. This might be less than\n\ | |
1858 | or greater than the ABI-defined value returned by\n\ | |
1859 | @code{TARGET_VECTOR_ALIGNMENT}. It can be equal to the alignment of\n\ | |
1860 | a single element, in which case the vectorizer will not try to optimize\n\ | |
1861 | for alignment.\n\ | |
1862 | \n\ | |
1863 | The default hook returns @code{TYPE_ALIGN (@var{type})}, which is\n\ | |
1864 | correct for most targets.", | |
ca31798e | 1865 | poly_uint64, (const_tree type), |
f702e7d4 RS |
1866 | default_preferred_vector_alignment) |
1867 | ||
38f8b050 | 1868 | /* Return true if vector alignment is reachable (by peeling N |
c2873892 | 1869 | iterations) for the given scalar type. */ |
38f8b050 JR |
1870 | DEFHOOK |
1871 | (vector_alignment_reachable, | |
4d3907c2 ML |
1872 | "Return true if vector alignment is reachable (by peeling N iterations)\n\ |
1873 | for the given scalar type @var{type}. @var{is_packed} is false if the scalar\n\ | |
1874 | access using @var{type} is known to be naturally aligned.", | |
38f8b050 JR |
1875 | bool, (const_tree type, bool is_packed), |
1876 | default_builtin_vector_alignment_reachable) | |
1877 | ||
38f8b050 | 1878 | DEFHOOK |
f151c9e1 RS |
1879 | (vec_perm_const, |
1880 | "This hook is used to test whether the target can permute up to two\n\ | |
1881 | vectors of mode @var{mode} using the permutation vector @code{sel}, and\n\ | |
1882 | also to emit such a permutation. In the former case @var{in0}, @var{in1}\n\ | |
1883 | and @var{out} are all null. In the latter case @var{in0} and @var{in1} are\n\ | |
1884 | the source vectors and @var{out} is the destination vector; all three are\n\ | |
841548f0 | 1885 | operands of mode @var{mode}. @var{in1} is the same as @var{in0} if\n\ |
f151c9e1 RS |
1886 | @var{sel} describes a permutation on one vector instead of two.\n\ |
1887 | \n\ | |
1888 | Return true if the operation is possible, emitting instructions for it\n\ | |
1889 | if rtxes are provided.\n\ | |
1890 | \n\ | |
1891 | @cindex @code{vec_perm@var{m}} instruction pattern\n\ | |
1892 | If the hook returns false for a mode with multibyte elements, GCC will\n\ | |
1893 | try the equivalent byte operation. If that also fails, it will try forcing\n\ | |
1894 | the selector into a register and using the @var{vec_perm@var{mode}}\n\ | |
1895 | instruction pattern. There is no need for the hook to handle these two\n\ | |
1896 | implementation approaches itself.", | |
1897 | bool, (machine_mode mode, rtx output, rtx in0, rtx in1, | |
1898 | const vec_perm_indices &sel), | |
22e4dee7 | 1899 | NULL) |
38f8b050 JR |
1900 | |
1901 | /* Return true if the target supports misaligned store/load of a | |
1902 | specific factor denoted in the third parameter. The last parameter | |
1903 | is true if the access is defined in a packed struct. */ | |
1904 | DEFHOOK | |
1905 | (support_vector_misalignment, | |
673c2f63 JM |
1906 | "This hook should return true if the target supports misaligned vector\n\ |
1907 | store/load of a specific factor denoted in the @var{misalignment}\n\ | |
1908 | parameter. The vector store/load should be of machine mode @var{mode} and\n\ | |
1909 | the elements in the vectors should be of type @var{type}. @var{is_packed}\n\ | |
1910 | parameter is true if the memory access is defined in a packed struct.", | |
38f8b050 | 1911 | bool, |
ef4bddc2 | 1912 | (machine_mode mode, const_tree type, int misalignment, bool is_packed), |
38f8b050 JR |
1913 | default_builtin_support_vector_misalignment) |
1914 | ||
cc4b5170 RG |
1915 | /* Returns the preferred mode for SIMD operations for the specified |
1916 | scalar mode. */ | |
26983c22 | 1917 | DEFHOOK |
cc4b5170 | 1918 | (preferred_simd_mode, |
673c2f63 JM |
1919 | "This hook should return the preferred mode for vectorizing scalar\n\ |
1920 | mode @var{mode}. The default is\n\ | |
1921 | equal to @code{word_mode}, because the vectorizer can do some\n\ | |
1922 | transformations even in absence of specialized @acronym{SIMD} hardware.", | |
ef4bddc2 | 1923 | machine_mode, |
005ba29c | 1924 | (scalar_mode mode), |
cc4b5170 | 1925 | default_preferred_simd_mode) |
26983c22 | 1926 | |
c803b2a9 RB |
1927 | /* Returns the preferred mode for splitting SIMD reductions to. */ |
1928 | DEFHOOK | |
1929 | (split_reduction, | |
1930 | "This hook should return the preferred mode to split the final reduction\n\ | |
1931 | step on @var{mode} to. The reduction is then carried out reducing upper\n\ | |
1932 | against lower halves of vectors recursively until the specified mode is\n\ | |
1933 | reached. The default is @var{mode} which means no splitting.", | |
1934 | machine_mode, | |
1935 | (machine_mode), | |
1936 | default_split_reduction) | |
1937 | ||
767f865f RG |
1938 | /* Returns a mask of vector sizes to iterate over when auto-vectorizing |
1939 | after processing the preferred one derived from preferred_simd_mode. */ | |
1940 | DEFHOOK | |
e021fb86 RS |
1941 | (autovectorize_vector_modes, |
1942 | "If using the mode returned by @code{TARGET_VECTORIZE_PREFERRED_SIMD_MODE}\n\ | |
1943 | is not the only approach worth considering, this hook should add one mode to\n\ | |
1944 | @var{modes} for each useful alternative approach. These modes are then\n\ | |
1945 | passed to @code{TARGET_VECTORIZE_RELATED_MODE} to obtain the vector mode\n\ | |
1946 | for a given element mode.\n\ | |
1947 | \n\ | |
1948 | The modes returned in @var{modes} should use the smallest element mode\n\ | |
1949 | possible for the vectorization approach that they represent, preferring\n\ | |
1950 | integer modes over floating-poing modes in the event of a tie. The first\n\ | |
1951 | mode should be the @code{TARGET_VECTORIZE_PREFERRED_SIMD_MODE} for its\n\ | |
1952 | element mode.\n\ | |
1953 | \n\ | |
1954 | If @var{all} is true, add suitable vector modes even when they are generally\n\ | |
f63445e5 | 1955 | not expected to be worthwhile.\n\ |
86e36728 | 1956 | \n\ |
bcc7e346 RS |
1957 | The hook returns a bitmask of flags that control how the modes in\n\ |
1958 | @var{modes} are used. The flags are:\n\ | |
1959 | @table @code\n\ | |
1960 | @item VECT_COMPARE_COSTS\n\ | |
1961 | Tells the loop vectorizer to try all the provided modes and pick the one\n\ | |
1962 | with the lowest cost. By default the vectorizer will choose the first\n\ | |
1963 | mode that works.\n\ | |
1964 | @end table\n\ | |
1965 | \n\ | |
86e36728 RS |
1966 | The hook does not need to do anything if the vector returned by\n\ |
1967 | @code{TARGET_VECTORIZE_PREFERRED_SIMD_MODE} is the only one relevant\n\ | |
bcc7e346 RS |
1968 | for autovectorization. The default implementation adds no modes and\n\ |
1969 | returns 0.", | |
1970 | unsigned int, | |
e021fb86 RS |
1971 | (vector_modes *modes, bool all), |
1972 | default_autovectorize_vector_modes) | |
767f865f | 1973 | |
f0955233 RS |
1974 | DEFHOOK |
1975 | (related_mode, | |
1976 | "If a piece of code is using vector mode @var{vector_mode} and also wants\n\ | |
1977 | to operate on elements of mode @var{element_mode}, return the vector mode\n\ | |
1978 | it should use for those elements. If @var{nunits} is nonzero, ensure that\n\ | |
1979 | the mode has exactly @var{nunits} elements, otherwise pick whichever vector\n\ | |
1980 | size pairs the most naturally with @var{vector_mode}. Return an empty\n\ | |
1981 | @code{opt_machine_mode} if there is no supported vector mode with the\n\ | |
1982 | required properties.\n\ | |
1983 | \n\ | |
1984 | There is no prescribed way of handling the case in which @var{nunits}\n\ | |
1985 | is zero. One common choice is to pick a vector mode with the same size\n\ | |
1986 | as @var{vector_mode}; this is the natural choice if the target has a\n\ | |
1987 | fixed vector size. Another option is to choose a vector mode with the\n\ | |
1988 | same number of elements as @var{vector_mode}; this is the natural choice\n\ | |
1989 | if the target has a fixed number of elements. Alternatively, the hook\n\ | |
1990 | might choose a middle ground, such as trying to keep the number of\n\ | |
1991 | elements as similar as possible while applying maximum and minimum\n\ | |
1992 | vector sizes.\n\ | |
1993 | \n\ | |
1994 | The default implementation uses @code{mode_for_vector} to find the\n\ | |
1995 | requested mode, returning a mode with the same size as @var{vector_mode}\n\ | |
1996 | when @var{nunits} is zero. This is the correct behavior for most targets.", | |
1997 | opt_machine_mode, | |
1998 | (machine_mode vector_mode, scalar_mode element_mode, poly_uint64 nunits), | |
1999 | default_vectorize_related_mode) | |
2000 | ||
9f47c7e5 IE |
2001 | /* Function to get a target mode for a vector mask. */ |
2002 | DEFHOOK | |
2003 | (get_mask_mode, | |
10116ec1 RS |
2004 | "Return the mode to use for a vector mask that holds one boolean\n\ |
2005 | result for each element of vector mode @var{mode}. The returned mask mode\n\ | |
2006 | can be a vector of integers (class @code{MODE_VECTOR_INT}), a vector of\n\ | |
2007 | booleans (class @code{MODE_VECTOR_BOOL}) or a scalar integer (class\n\ | |
2008 | @code{MODE_INT}). Return an empty @code{opt_machine_mode} if no such\n\ | |
2009 | mask mode exists.\n\ | |
2010 | \n\ | |
2011 | The default implementation returns a @code{MODE_VECTOR_INT} with the\n\ | |
2012 | same size and number of elements as @var{mode}, if such a mode exists.", | |
3981fbb6 | 2013 | opt_machine_mode, |
10116ec1 | 2014 | (machine_mode mode), |
9f47c7e5 IE |
2015 | default_get_mask_mode) |
2016 | ||
76a34e3f RS |
2017 | /* Function to say whether a masked operation is expensive when the |
2018 | mask is all zeros. */ | |
2019 | DEFHOOK | |
2020 | (empty_mask_is_expensive, | |
2021 | "This hook returns true if masked internal function @var{ifn} (really of\n\ | |
2022 | type @code{internal_fn}) should be considered expensive when the mask is\n\ | |
2023 | all zeros. GCC can then try to branch around the instruction instead.", | |
2024 | bool, | |
2025 | (unsigned ifn), | |
2026 | default_empty_mask_is_expensive) | |
2027 | ||
aec7ae7d JJ |
2028 | /* Target builtin that implements vector gather operation. */ |
2029 | DEFHOOK | |
2030 | (builtin_gather, | |
673c2f63 JM |
2031 | "Target builtin that implements vector gather operation. @var{mem_vectype}\n\ |
2032 | is the vector type of the load and @var{index_type} is scalar type of\n\ | |
2033 | the index, scaled by @var{scale}.\n\ | |
2034 | The default is @code{NULL_TREE} which means to not vectorize gather\n\ | |
2035 | loads.", | |
aec7ae7d JJ |
2036 | tree, |
2037 | (const_tree mem_vectype, const_tree index_type, int scale), | |
2038 | NULL) | |
2039 | ||
3bab6342 AT |
2040 | /* Target builtin that implements vector scatter operation. */ |
2041 | DEFHOOK | |
2042 | (builtin_scatter, | |
2043 | "Target builtin that implements vector scatter operation. @var{vectype}\n\ | |
2044 | is the vector type of the store and @var{index_type} is scalar type of\n\ | |
2045 | the index, scaled by @var{scale}.\n\ | |
2046 | The default is @code{NULL_TREE} which means to not vectorize scatter\n\ | |
2047 | stores.", | |
2048 | tree, | |
2049 | (const_tree vectype, const_tree index_type, int scale), | |
2050 | NULL) | |
2051 | ||
c3e7ee41 BS |
2052 | /* Target function to initialize the cost model for a loop or block. */ |
2053 | DEFHOOK | |
6239dd05 | 2054 | (create_costs, |
4d3907c2 ML |
2055 | "This hook should initialize target-specific data structures in preparation\n\ |
2056 | for modeling the costs of vectorizing a loop or basic block. The default\n\ | |
2057 | allocates three unsigned integers for accumulating costs for the prologue,\n\ | |
2058 | body, and epilogue of the loop or basic block. If @var{loop_info} is\n\ | |
2059 | non-NULL, it identifies the loop being vectorized; otherwise a single block\n\ | |
2060 | is being vectorized. If @var{costing_for_scalar} is true, it indicates the\n\ | |
2061 | current cost model is for the scalar version of a loop or block; otherwise\n\ | |
2062 | it is for the vector version.", | |
6239dd05 RS |
2063 | class vector_costs *, |
2064 | (vec_info *vinfo, bool costing_for_scalar), | |
2065 | default_vectorize_create_costs) | |
c3e7ee41 | 2066 | |
38f8b050 JR |
2067 | HOOK_VECTOR_END (vectorize) |
2068 | ||
2069 | #undef HOOK_PREFIX | |
2070 | #define HOOK_PREFIX "TARGET_" | |
2071 | ||
6a86928d RS |
2072 | DEFHOOK |
2073 | (preferred_else_value, | |
2074 | "This hook returns the target's preferred final argument for a call\n\ | |
2075 | to conditional internal function @var{ifn} (really of type\n\ | |
2076 | @code{internal_fn}). @var{type} specifies the return type of the\n\ | |
2077 | function and @var{ops} are the operands to the conditional operation,\n\ | |
2078 | of which there are @var{nops}.\n\ | |
2079 | \n\ | |
2080 | For example, if @var{ifn} is @code{IFN_COND_ADD}, the hook returns\n\ | |
2081 | a value of type @var{type} that should be used when @samp{@var{ops}[0]}\n\ | |
2082 | and @samp{@var{ops}[1]} are conditionally added together.\n\ | |
2083 | \n\ | |
2084 | This hook is only relevant if the target supports conditional patterns\n\ | |
2085 | like @code{cond_add@var{m}}. The default implementation returns a zero\n\ | |
2086 | constant of type @var{type}.", | |
2087 | tree, | |
2088 | (unsigned ifn, tree type, unsigned nops, tree *ops), | |
2089 | default_preferred_else_value) | |
2090 | ||
ec6fe917 IV |
2091 | DEFHOOK |
2092 | (record_offload_symbol, | |
2093 | "Used when offloaded functions are seen in the compilation unit and no named\n\ | |
2094 | sections are available. It is called once for each symbol that must be\n\ | |
2095 | recorded in the offload function and variable table.", | |
2096 | void, (tree), | |
2097 | hook_void_tree) | |
2098 | ||
6d2b7199 BS |
2099 | DEFHOOKPOD |
2100 | (absolute_biggest_alignment, | |
2101 | "If defined, this target hook specifies the absolute biggest alignment\n\ | |
2102 | that a type or variable can have on this machine, otherwise,\n\ | |
2103 | @code{BIGGEST_ALIGNMENT} is used.", | |
2104 | HOST_WIDE_INT, BIGGEST_ALIGNMENT) | |
2105 | ||
38f8b050 JR |
2106 | /* Allow target specific overriding of option settings after options have |
2107 | been changed by an attribute or pragma or when it is reset at the | |
2108 | end of the code affected by an attribute or pragma. */ | |
2109 | DEFHOOK | |
2110 | (override_options_after_change, | |
673c2f63 JM |
2111 | "This target function is similar to the hook @code{TARGET_OPTION_OVERRIDE}\n\ |
2112 | but is called when the optimize level is changed via an attribute or\n\ | |
2113 | pragma or when it is reset at the end of the code affected by the\n\ | |
2114 | attribute or pragma. It is not called at the beginning of compilation\n\ | |
2115 | when @code{TARGET_OPTION_OVERRIDE} is called so if you want to perform these\n\ | |
2116 | actions then, you should have @code{TARGET_OPTION_OVERRIDE} call\n\ | |
2117 | @code{TARGET_OVERRIDE_OPTIONS_AFTER_CHANGE}.", | |
38f8b050 JR |
2118 | void, (void), |
2119 | hook_void_void) | |
2120 | ||
c713ddc0 BS |
2121 | DEFHOOK |
2122 | (offload_options, | |
2123 | "Used when writing out the list of options into an LTO file. It should\n\ | |
2124 | translate any relevant target-specific options (such as the ABI in use)\n\ | |
2125 | into one of the @option{-foffload} options that exist as a common interface\n\ | |
2126 | to express such options. It should return a string containing these options,\n\ | |
2127 | separated by spaces, which the caller will free.\n", | |
2128 | char *, (void), hook_charptr_void_null) | |
2129 | ||
38f8b050 JR |
2130 | DEFHOOK_UNDOC |
2131 | (eh_return_filter_mode, | |
2132 | "Return machine mode for filter value.", | |
095a2d76 | 2133 | scalar_int_mode, (void), |
38f8b050 JR |
2134 | default_eh_return_filter_mode) |
2135 | ||
2136 | /* Return machine mode for libgcc expanded cmp instructions. */ | |
2137 | DEFHOOK | |
2138 | (libgcc_cmp_return_mode, | |
673c2f63 JM |
2139 | "This target hook should return the mode to be used for the return value\n\ |
2140 | of compare instructions expanded to libgcc calls. If not defined\n\ | |
2141 | @code{word_mode} is returned which is the right choice for a majority of\n\ | |
2142 | targets.", | |
095a2d76 | 2143 | scalar_int_mode, (void), |
38f8b050 JR |
2144 | default_libgcc_cmp_return_mode) |
2145 | ||
2146 | /* Return machine mode for libgcc expanded shift instructions. */ | |
2147 | DEFHOOK | |
2148 | (libgcc_shift_count_mode, | |
673c2f63 JM |
2149 | "This target hook should return the mode to be used for the shift count operand\n\ |
2150 | of shift instructions expanded to libgcc calls. If not defined\n\ | |
2151 | @code{word_mode} is returned which is the right choice for a majority of\n\ | |
2152 | targets.", | |
095a2d76 | 2153 | scalar_int_mode, (void), |
38f8b050 JR |
2154 | default_libgcc_shift_count_mode) |
2155 | ||
2156 | /* Return machine mode to be used for _Unwind_Word type. */ | |
2157 | DEFHOOK | |
2158 | (unwind_word_mode, | |
673c2f63 JM |
2159 | "Return machine mode to be used for @code{_Unwind_Word} type.\n\ |
2160 | The default is to use @code{word_mode}.", | |
095a2d76 | 2161 | scalar_int_mode, (void), |
38f8b050 JR |
2162 | default_unwind_word_mode) |
2163 | ||
2164 | /* Given two decls, merge their attributes and return the result. */ | |
2165 | DEFHOOK | |
2166 | (merge_decl_attributes, | |
673c2f63 JM |
2167 | "Define this target hook if the merging of decl attributes needs special\n\ |
2168 | handling. If defined, the result is a list of the combined\n\ | |
2169 | @code{DECL_ATTRIBUTES} of @var{olddecl} and @var{newdecl}.\n\ | |
2170 | @var{newdecl} is a duplicate declaration of @var{olddecl}. Examples of\n\ | |
2171 | when this is needed are when one attribute overrides another, or when an\n\ | |
2172 | attribute is nullified by a subsequent definition. This function may\n\ | |
2173 | call @code{merge_attributes} to handle machine-independent merging.\n\ | |
2174 | \n\ | |
2175 | @findex TARGET_DLLIMPORT_DECL_ATTRIBUTES\n\ | |
2176 | If the only target-specific handling you require is @samp{dllimport}\n\ | |
2177 | for Microsoft Windows targets, you should define the macro\n\ | |
2178 | @code{TARGET_DLLIMPORT_DECL_ATTRIBUTES} to @code{1}. The compiler\n\ | |
2179 | will then define a function called\n\ | |
2180 | @code{merge_dllimport_decl_attributes} which can then be defined as\n\ | |
2181 | the expansion of @code{TARGET_MERGE_DECL_ATTRIBUTES}. You can also\n\ | |
2182 | add @code{handle_dll_attribute} in the attribute table for your port\n\ | |
2183 | to perform initial processing of the @samp{dllimport} and\n\ | |
2184 | @samp{dllexport} attributes. This is done in @file{i386/cygwin.h} and\n\ | |
e53b6e56 | 2185 | @file{i386/i386.cc}, for example.", |
38f8b050 JR |
2186 | tree, (tree olddecl, tree newdecl), |
2187 | merge_decl_attributes) | |
2188 | ||
2189 | /* Given two types, merge their attributes and return the result. */ | |
2190 | DEFHOOK | |
2191 | (merge_type_attributes, | |
673c2f63 JM |
2192 | "Define this target hook if the merging of type attributes needs special\n\ |
2193 | handling. If defined, the result is a list of the combined\n\ | |
2194 | @code{TYPE_ATTRIBUTES} of @var{type1} and @var{type2}. It is assumed\n\ | |
2195 | that @code{comptypes} has already been called and returned 1. This\n\ | |
2196 | function may call @code{merge_attributes} to handle machine-independent\n\ | |
2197 | merging.", | |
38f8b050 JR |
2198 | tree, (tree type1, tree type2), |
2199 | merge_type_attributes) | |
2200 | ||
2201 | /* Table of machine attributes and functions to handle them. | |
2202 | Ignored if NULL. */ | |
2203 | DEFHOOKPOD | |
2204 | (attribute_table, | |
673c2f63 | 2205 | "If defined, this target hook points to an array of @samp{struct\n\ |
15ab4e1e | 2206 | attribute_spec} (defined in @file{tree-core.h}) specifying the machine\n\ |
673c2f63 JM |
2207 | specific attributes for this target and some of the restrictions on the\n\ |
2208 | entities to which these attributes are applied and the arguments they\n\ | |
2209 | take.", | |
38f8b050 JR |
2210 | const struct attribute_spec *, NULL) |
2211 | ||
2212 | /* Return true iff attribute NAME expects a plain identifier as its first | |
2213 | argument. */ | |
2214 | DEFHOOK | |
2215 | (attribute_takes_identifier_p, | |
673c2f63 JM |
2216 | "If defined, this target hook is a function which returns true if the\n\ |
2217 | machine-specific attribute named @var{name} expects an identifier\n\ | |
2218 | given as its first argument to be passed on as a plain identifier, not\n\ | |
2219 | subjected to name lookup. If this is not defined, the default is\n\ | |
2220 | false for all machine-specific attributes.", | |
38f8b050 JR |
2221 | bool, (const_tree name), |
2222 | hook_bool_const_tree_false) | |
2223 | ||
2224 | /* Return zero if the attributes on TYPE1 and TYPE2 are incompatible, | |
2225 | one if they are compatible and two if they are nearly compatible | |
2226 | (which causes a warning to be generated). */ | |
2227 | DEFHOOK | |
2228 | (comp_type_attributes, | |
673c2f63 JM |
2229 | "If defined, this target hook is a function which returns zero if the attributes on\n\ |
2230 | @var{type1} and @var{type2} are incompatible, one if they are compatible,\n\ | |
2231 | and two if they are nearly compatible (which causes a warning to be\n\ | |
2232 | generated). If this is not defined, machine-specific attributes are\n\ | |
2233 | supposed always to be compatible.", | |
38f8b050 JR |
2234 | int, (const_tree type1, const_tree type2), |
2235 | hook_int_const_tree_const_tree_1) | |
2236 | ||
2237 | /* Assign default attributes to the newly defined TYPE. */ | |
2238 | DEFHOOK | |
2239 | (set_default_type_attributes, | |
673c2f63 JM |
2240 | "If defined, this target hook is a function which assigns default attributes to\n\ |
2241 | the newly defined @var{type}.", | |
38f8b050 JR |
2242 | void, (tree type), |
2243 | hook_void_tree) | |
2244 | ||
2245 | /* Insert attributes on the newly created DECL. */ | |
2246 | DEFHOOK | |
2247 | (insert_attributes, | |
673c2f63 JM |
2248 | "Define this target hook if you want to be able to add attributes to a decl\n\ |
2249 | when it is being created. This is normally useful for back ends which\n\ | |
2250 | wish to implement a pragma by using the attributes which correspond to\n\ | |
2251 | the pragma's effect. The @var{node} argument is the decl which is being\n\ | |
2252 | created. The @var{attr_ptr} argument is a pointer to the attribute list\n\ | |
2253 | for this decl. The list itself should not be modified, since it may be\n\ | |
2254 | shared with other decls, but attributes may be chained on the head of\n\ | |
2255 | the list and @code{*@var{attr_ptr}} modified to point to the new\n\ | |
2256 | attributes, or a copy of the list may be made if further changes are\n\ | |
2257 | needed.", | |
38f8b050 JR |
2258 | void, (tree node, tree *attr_ptr), |
2259 | hook_void_tree_treeptr) | |
2260 | ||
7a4418a5 JL |
2261 | /* Perform additional target-specific processing of generic attributes. */ |
2262 | DEFHOOK | |
2263 | (handle_generic_attribute, | |
2264 | "Define this target hook if you want to be able to perform additional\n\ | |
2265 | target-specific processing of an attribute which is handled generically\n\ | |
2266 | by a front end. The arguments are the same as those which are passed to\n\ | |
2267 | attribute handlers. So far this only affects the @var{noinit} and\n\ | |
2268 | @var{section} attribute.", | |
2269 | tree, (tree *node, tree name, tree args, int flags, bool *no_add_attrs), | |
2270 | hook_tree_treeptr_tree_tree_int_boolptr_null) | |
2271 | ||
38f8b050 JR |
2272 | /* Return true if FNDECL (which has at least one machine attribute) |
2273 | can be inlined despite its machine attributes, false otherwise. */ | |
2274 | DEFHOOK | |
2275 | (function_attribute_inlinable_p, | |
673c2f63 | 2276 | "@cindex inlining\n\ |
5bd40ade | 2277 | This target hook returns @code{true} if it is OK to inline @var{fndecl}\n\ |
673c2f63 JM |
2278 | into the current function, despite its having target-specific\n\ |
2279 | attributes, @code{false} otherwise. By default, if a function has a\n\ | |
2280 | target specific attribute attached to it, it will not be inlined.", | |
38f8b050 JR |
2281 | bool, (const_tree fndecl), |
2282 | hook_bool_const_tree_false) | |
2283 | ||
2284 | /* Return true if bitfields in RECORD_TYPE should follow the | |
2285 | Microsoft Visual C++ bitfield layout rules. */ | |
2286 | DEFHOOK | |
2287 | (ms_bitfield_layout_p, | |
673c2f63 JM |
2288 | "This target hook returns @code{true} if bit-fields in the given\n\ |
2289 | @var{record_type} are to be laid out following the rules of Microsoft\n\ | |
2290 | Visual C/C++, namely: (i) a bit-field won't share the same storage\n\ | |
2291 | unit with the previous bit-field if their underlying types have\n\ | |
2292 | different sizes, and the bit-field will be aligned to the highest\n\ | |
2293 | alignment of the underlying types of itself and of the previous\n\ | |
2294 | bit-field; (ii) a zero-sized bit-field will affect the alignment of\n\ | |
2295 | the whole enclosing structure, even if it is unnamed; except that\n\ | |
2296 | (iii) a zero-sized bit-field will be disregarded unless it follows\n\ | |
2297 | another bit-field of nonzero size. If this hook returns @code{true},\n\ | |
2298 | other macros that control bit-field layout are ignored.\n\ | |
2299 | \n\ | |
2300 | When a bit-field is inserted into a packed record, the whole size\n\ | |
2301 | of the underlying type is used by one or more same-size adjacent\n\ | |
2302 | bit-fields (that is, if its long:3, 32 bits is used in the record,\n\ | |
2303 | and any additional adjacent long bit-fields are packed into the same\n\ | |
2304 | chunk of 32 bits. However, if the size changes, a new field of that\n\ | |
2305 | size is allocated). In an unpacked record, this is the same as using\n\ | |
2306 | alignment, but not equivalent when packing.\n\ | |
2307 | \n\ | |
2308 | If both MS bit-fields and @samp{__attribute__((packed))} are used,\n\ | |
2309 | the latter will take precedence. If @samp{__attribute__((packed))} is\n\ | |
2310 | used on a single field when MS bit-fields are in use, it will take\n\ | |
2311 | precedence for that field, but the alignment of the rest of the structure\n\ | |
2312 | may affect its placement.", | |
38f8b050 JR |
2313 | bool, (const_tree record_type), |
2314 | hook_bool_const_tree_false) | |
2315 | ||
2e681adf JR |
2316 | /* For now this is only an interface to WORDS_BIG_ENDIAN for |
2317 | target-independent code like the front ends, need performance testing | |
2318 | before switching completely to the target hook. */ | |
2319 | DEFHOOK_UNDOC | |
2320 | (words_big_endian, | |
2321 | "", | |
2322 | bool, (void), | |
2323 | targhook_words_big_endian) | |
2324 | ||
2325 | /* Likewise for FLOAT_WORDS_BIG_ENDIAN. */ | |
2326 | DEFHOOK_UNDOC | |
2327 | (float_words_big_endian, | |
2328 | "", | |
2329 | bool, (void), | |
2330 | targhook_float_words_big_endian) | |
2331 | ||
9193fb05 JM |
2332 | DEFHOOK |
2333 | (float_exceptions_rounding_supported_p, | |
4d3907c2 ML |
2334 | "Returns true if the target supports IEEE 754 floating-point exceptions\n\ |
2335 | and rounding modes, false otherwise. This is intended to relate to the\n\ | |
2336 | @code{float} and @code{double} types, but not necessarily @code{long double}.\n\ | |
2337 | By default, returns true if the @code{adddf3} instruction pattern is\n\ | |
2338 | available and false otherwise, on the assumption that hardware floating\n\ | |
2339 | point supports exceptions and rounding modes but software floating point\n\ | |
2340 | does not.", | |
9193fb05 JM |
2341 | bool, (void), |
2342 | default_float_exceptions_rounding_supported_p) | |
2343 | ||
38f8b050 JR |
2344 | /* True if the target supports decimal floating point. */ |
2345 | DEFHOOK | |
2346 | (decimal_float_supported_p, | |
673c2f63 | 2347 | "Returns true if the target supports decimal floating point.", |
38f8b050 JR |
2348 | bool, (void), |
2349 | default_decimal_float_supported_p) | |
2350 | ||
2351 | /* True if the target supports fixed-point. */ | |
2352 | DEFHOOK | |
2353 | (fixed_point_supported_p, | |
673c2f63 | 2354 | "Returns true if the target supports fixed-point arithmetic.", |
38f8b050 JR |
2355 | bool, (void), |
2356 | default_fixed_point_supported_p) | |
2357 | ||
2358 | /* Return true if anonymous bitfields affect structure alignment. */ | |
2359 | DEFHOOK | |
2360 | (align_anon_bitfield, | |
673c2f63 JM |
2361 | "When @code{PCC_BITFIELD_TYPE_MATTERS} is true this hook will determine\n\ |
2362 | whether unnamed bitfields affect the alignment of the containing\n\ | |
2363 | structure. The hook should return true if the structure should inherit\n\ | |
2364 | the alignment requirements of an unnamed bitfield's type.", | |
38f8b050 JR |
2365 | bool, (void), |
2366 | hook_bool_void_false) | |
2367 | ||
2368 | /* Return true if volatile bitfields should use the narrowest type possible. | |
2369 | Return false if they should use the container type. */ | |
2370 | DEFHOOK | |
2371 | (narrow_volatile_bitfield, | |
673c2f63 JM |
2372 | "This target hook should return @code{true} if accesses to volatile bitfields\n\ |
2373 | should use the narrowest mode possible. It should return @code{false} if\n\ | |
2374 | these accesses should use the bitfield container type.\n\ | |
2375 | \n\ | |
7d0b9a9c | 2376 | The default is @code{false}.", |
38f8b050 JR |
2377 | bool, (void), |
2378 | hook_bool_void_false) | |
2379 | ||
2380 | /* Set up target-specific built-in functions. */ | |
2381 | DEFHOOK | |
2382 | (init_builtins, | |
673c2f63 JM |
2383 | "Define this hook if you have any machine-specific built-in functions\n\ |
2384 | that need to be defined. It should be a function that performs the\n\ | |
2385 | necessary setup.\n\ | |
2386 | \n\ | |
2387 | Machine specific built-in functions can be useful to expand special machine\n\ | |
2388 | instructions that would otherwise not normally be generated because\n\ | |
2389 | they have no equivalent in the source language (for example, SIMD vector\n\ | |
2390 | instructions or prefetch instructions).\n\ | |
2391 | \n\ | |
2392 | To create a built-in function, call the function\n\ | |
2393 | @code{lang_hooks.builtin_function}\n\ | |
2394 | which is defined by the language front end. You can use any type nodes set\n\ | |
2395 | up by @code{build_common_tree_nodes};\n\ | |
2396 | only language front ends that use those two functions will call\n\ | |
2397 | @samp{TARGET_INIT_BUILTINS}.", | |
38f8b050 JR |
2398 | void, (void), |
2399 | hook_void_void) | |
2400 | ||
2401 | /* Initialize (if INITIALIZE_P is true) and return the target-specific | |
2402 | built-in function decl for CODE. | |
2403 | Return NULL if that is not possible. Return error_mark_node if CODE | |
2404 | is outside of the range of valid target builtin function codes. */ | |
2405 | DEFHOOK | |
2406 | (builtin_decl, | |
673c2f63 JM |
2407 | "Define this hook if you have any machine-specific built-in functions\n\ |
2408 | that need to be defined. It should be a function that returns the\n\ | |
2409 | builtin function declaration for the builtin function code @var{code}.\n\ | |
2410 | If there is no such builtin and it cannot be initialized at this time\n\ | |
2411 | if @var{initialize_p} is true the function should return @code{NULL_TREE}.\n\ | |
2412 | If @var{code} is out of range the function should return\n\ | |
2413 | @code{error_mark_node}.", | |
38f8b050 JR |
2414 | tree, (unsigned code, bool initialize_p), NULL) |
2415 | ||
2416 | /* Expand a target-specific builtin. */ | |
2417 | DEFHOOK | |
2418 | (expand_builtin, | |
673c2f63 JM |
2419 | "\n\ |
2420 | Expand a call to a machine specific built-in function that was set up by\n\ | |
2421 | @samp{TARGET_INIT_BUILTINS}. @var{exp} is the expression for the\n\ | |
2422 | function call; the result should go to @var{target} if that is\n\ | |
2423 | convenient, and have mode @var{mode} if that is convenient.\n\ | |
2424 | @var{subtarget} may be used as the target for computing one of\n\ | |
2425 | @var{exp}'s operands. @var{ignore} is nonzero if the value is to be\n\ | |
2426 | ignored. This function should return the result of the call to the\n\ | |
2427 | built-in function.", | |
38f8b050 | 2428 | rtx, |
ef4bddc2 | 2429 | (tree exp, rtx target, rtx subtarget, machine_mode mode, int ignore), |
38f8b050 JR |
2430 | default_expand_builtin) |
2431 | ||
2432 | /* Select a replacement for a target-specific builtin. This is done | |
2433 | *before* regular type checking, and so allows the target to | |
2434 | implement a crude form of function overloading. The result is a | |
2435 | complete expression that implements the operation. PARAMS really | |
2436 | has type VEC(tree,gc)*, but we don't want to include tree.h here. */ | |
d66f5459 | 2437 | DEFHOOK |
38f8b050 | 2438 | (resolve_overloaded_builtin, |
673c2f63 JM |
2439 | "Select a replacement for a machine specific built-in function that\n\ |
2440 | was set up by @samp{TARGET_INIT_BUILTINS}. This is done\n\ | |
2441 | @emph{before} regular type checking, and so allows the target to\n\ | |
2442 | implement a crude form of function overloading. @var{fndecl} is the\n\ | |
2443 | declaration of the built-in function. @var{arglist} is the list of\n\ | |
2444 | arguments passed to the built-in function. The result is a\n\ | |
2445 | complete expression that implements the operation, usually\n\ | |
2446 | another @code{CALL_EXPR}.\n\ | |
2447 | @var{arglist} really has type @samp{VEC(tree,gc)*}", | |
d66f5459 | 2448 | tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL) |
38f8b050 | 2449 | |
c6447c20 RS |
2450 | DEFHOOK |
2451 | (check_builtin_call, | |
2452 | "Perform semantic checking on a call to a machine-specific built-in\n\ | |
2453 | function after its arguments have been constrained to the function\n\ | |
2454 | signature. Return true if the call is valid, otherwise report an error\n\ | |
2455 | and return false.\n\ | |
2456 | \n\ | |
2457 | This hook is called after @code{TARGET_RESOLVE_OVERLOADED_BUILTIN}.\n\ | |
2458 | The call was originally to built-in function @var{orig_fndecl},\n\ | |
2459 | but after the optional @code{TARGET_RESOLVE_OVERLOADED_BUILTIN}\n\ | |
2460 | step is now to built-in function @var{fndecl}. @var{loc} is the\n\ | |
2461 | location of the call and @var{args} is an array of function arguments,\n\ | |
2462 | of which there are @var{nargs}. @var{arg_loc} specifies the location\n\ | |
2463 | of each argument.", | |
2464 | bool, (location_t loc, vec<location_t> arg_loc, tree fndecl, | |
2465 | tree orig_fndecl, unsigned int nargs, tree *args), | |
2466 | NULL) | |
2467 | ||
ea679d55 JG |
2468 | /* Fold a target-specific builtin to a tree valid for both GIMPLE |
2469 | and GENERIC. */ | |
08914aaa | 2470 | DEFHOOK |
38f8b050 | 2471 | (fold_builtin, |
673c2f63 JM |
2472 | "Fold a call to a machine specific built-in function that was set up by\n\ |
2473 | @samp{TARGET_INIT_BUILTINS}. @var{fndecl} is the declaration of the\n\ | |
2474 | built-in function. @var{n_args} is the number of arguments passed to\n\ | |
2475 | the function; the arguments themselves are pointed to by @var{argp}.\n\ | |
2476 | The result is another tree, valid for both GIMPLE and GENERIC,\n\ | |
2477 | containing a simplified expression for the call's result. If\n\ | |
2478 | @var{ignore} is true the value will be ignored.", | |
08914aaa | 2479 | tree, (tree fndecl, int n_args, tree *argp, bool ignore), |
38f8b050 JR |
2480 | hook_tree_tree_int_treep_bool_null) |
2481 | ||
ea679d55 JG |
2482 | /* Fold a target-specific builtin to a valid GIMPLE tree. */ |
2483 | DEFHOOK | |
2484 | (gimple_fold_builtin, | |
2485 | "Fold a call to a machine specific built-in function that was set up\n\ | |
2486 | by @samp{TARGET_INIT_BUILTINS}. @var{gsi} points to the gimple\n\ | |
2487 | statement holding the function call. Returns true if any change\n\ | |
2488 | was made to the GIMPLE stream.", | |
2489 | bool, (gimple_stmt_iterator *gsi), | |
2490 | hook_bool_gsiptr_false) | |
2491 | ||
3649b9b7 ST |
2492 | /* Target hook is used to compare the target attributes in two functions to |
2493 | determine which function's features get higher priority. This is used | |
2494 | during function multi-versioning to figure out the order in which two | |
2495 | versions must be dispatched. A function version with a higher priority | |
2496 | is checked for dispatching earlier. DECL1 and DECL2 are | |
2497 | the two function decls that will be compared. It returns positive value | |
2498 | if DECL1 is higher priority, negative value if DECL2 is higher priority | |
2499 | and 0 if they are the same. */ | |
2500 | DEFHOOK | |
2501 | (compare_version_priority, | |
673c2f63 JM |
2502 | "This hook is used to compare the target attributes in two functions to\n\ |
2503 | determine which function's features get higher priority. This is used\n\ | |
2504 | during function multi-versioning to figure out the order in which two\n\ | |
2505 | versions must be dispatched. A function version with a higher priority\n\ | |
2506 | is checked for dispatching earlier. @var{decl1} and @var{decl2} are\n\ | |
2507 | the two function decls that will be compared.", | |
3649b9b7 ST |
2508 | int, (tree decl1, tree decl2), NULL) |
2509 | ||
2510 | /* Target hook is used to generate the dispatcher logic to invoke the right | |
2511 | function version at run-time for a given set of function versions. | |
2512 | ARG points to the callgraph node of the dispatcher function whose body | |
2513 | must be generated. */ | |
2514 | DEFHOOK | |
2515 | (generate_version_dispatcher_body, | |
673c2f63 JM |
2516 | "This hook is used to generate the dispatcher logic to invoke the right\n\ |
2517 | function version at run-time for a given set of function versions.\n\ | |
2518 | @var{arg} points to the callgraph node of the dispatcher function whose\n\ | |
2519 | body must be generated.", | |
3649b9b7 ST |
2520 | tree, (void *arg), NULL) |
2521 | ||
2522 | /* Target hook is used to get the dispatcher function for a set of function | |
2523 | versions. The dispatcher function is called to invoke the right function | |
2524 | version at run-time. DECL is one version from a set of semantically | |
2525 | identical versions. */ | |
2526 | DEFHOOK | |
2527 | (get_function_versions_dispatcher, | |
673c2f63 JM |
2528 | "This hook is used to get the dispatcher function for a set of function\n\ |
2529 | versions. The dispatcher function is called to invoke the right function\n\ | |
2530 | version at run-time. @var{decl} is one version from a set of semantically\n\ | |
2531 | identical versions.", | |
3649b9b7 ST |
2532 | tree, (void *decl), NULL) |
2533 | ||
38f8b050 | 2534 | /* Returns a code for a target-specific builtin that implements |
ee62a5a6 | 2535 | reciprocal of a target-specific function, or NULL_TREE if not available. */ |
89356d17 | 2536 | DEFHOOK |
38f8b050 | 2537 | (builtin_reciprocal, |
ee62a5a6 RS |
2538 | "This hook should return the DECL of a function that implements the\n\ |
2539 | reciprocal of the machine-specific builtin function @var{fndecl}, or\n\ | |
7b90c63a | 2540 | @code{NULL_TREE} if such a function is not available.", |
ee62a5a6 | 2541 | tree, (tree fndecl), |
38f8b050 JR |
2542 | default_builtin_reciprocal) |
2543 | ||
2544 | /* For a vendor-specific TYPE, return a pointer to a statically-allocated | |
2545 | string containing the C++ mangling for TYPE. In all other cases, return | |
2546 | NULL. */ | |
2547 | DEFHOOK | |
2548 | (mangle_type, | |
673c2f63 JM |
2549 | "If your target defines any fundamental types, or any types your target\n\ |
2550 | uses should be mangled differently from the default, define this hook\n\ | |
2551 | to return the appropriate encoding for these types as part of a C++\n\ | |
2552 | mangled name. The @var{type} argument is the tree structure representing\n\ | |
2553 | the type to be mangled. The hook may be applied to trees which are\n\ | |
2554 | not target-specific fundamental types; it should return @code{NULL}\n\ | |
2555 | for all such types, as well as arguments it does not recognize. If the\n\ | |
2556 | return value is not @code{NULL}, it must point to a statically-allocated\n\ | |
2557 | string constant.\n\ | |
2558 | \n\ | |
2559 | Target-specific fundamental types might be new fundamental types or\n\ | |
2560 | qualified versions of ordinary fundamental types. Encode new\n\ | |
2561 | fundamental types as @samp{@w{u @var{n} @var{name}}}, where @var{name}\n\ | |
2562 | is the name used for the type in source code, and @var{n} is the\n\ | |
2563 | length of @var{name} in decimal. Encode qualified versions of\n\ | |
2564 | ordinary types as @samp{@w{U @var{n} @var{name} @var{code}}}, where\n\ | |
2565 | @var{name} is the name used for the type qualifier in source code,\n\ | |
2566 | @var{n} is the length of @var{name} as above, and @var{code} is the\n\ | |
2567 | code used to represent the unqualified version of this type. (See\n\ | |
e53b6e56 | 2568 | @code{write_builtin_type} in @file{cp/mangle.cc} for the list of\n\ |
673c2f63 JM |
2569 | codes.) In both cases the spaces are for clarity; do not include any\n\ |
2570 | spaces in your string.\n\ | |
2571 | \n\ | |
2572 | This hook is applied to types prior to typedef resolution. If the mangled\n\ | |
2573 | name for a particular type depends only on that type's main variant, you\n\ | |
2574 | can perform typedef resolution yourself using @code{TYPE_MAIN_VARIANT}\n\ | |
2575 | before mangling.\n\ | |
2576 | \n\ | |
2577 | The default version of this hook always returns @code{NULL}, which is\n\ | |
2578 | appropriate for a target that does not define any new fundamental\n\ | |
2579 | types.", | |
38f8b050 JR |
2580 | const char *, (const_tree type), |
2581 | hook_constcharptr_const_tree_null) | |
2582 | ||
2583 | /* Make any adjustments to libfunc names needed for this target. */ | |
2584 | DEFHOOK | |
2585 | (init_libfuncs, | |
673c2f63 JM |
2586 | "This hook should declare additional library routines or rename\n\ |
2587 | existing ones, using the functions @code{set_optab_libfunc} and\n\ | |
e53b6e56 | 2588 | @code{init_one_libfunc} defined in @file{optabs.cc}.\n\ |
673c2f63 JM |
2589 | @code{init_optabs} calls this macro after initializing all the normal\n\ |
2590 | library routines.\n\ | |
2591 | \n\ | |
2592 | The default is to do nothing. Most ports don't need to define this hook.", | |
38f8b050 JR |
2593 | void, (void), |
2594 | hook_void_void) | |
2595 | ||
cdbf4541 BS |
2596 | /* Add a __gnu_ prefix to library functions rather than just __. */ |
2597 | DEFHOOKPOD | |
2598 | (libfunc_gnu_prefix, | |
2599 | "If false (the default), internal library routines start with two\n\ | |
2600 | underscores. If set to true, these routines start with @code{__gnu_}\n\ | |
2601 | instead. E.g., @code{__muldi3} changes to @code{__gnu_muldi3}. This\n\ | |
2602 | currently only affects functions defined in @file{libgcc2.c}. If this\n\ | |
2603 | is set to true, the @file{tm.h} file must also\n\ | |
2604 | @code{#define LIBGCC2_GNU_PREFIX}.", | |
2605 | bool, false) | |
2606 | ||
38f8b050 JR |
2607 | /* Given a decl, a section name, and whether the decl initializer |
2608 | has relocs, choose attributes for the section. */ | |
2609 | /* ??? Should be merged with SELECT_SECTION and UNIQUE_SECTION. */ | |
2610 | DEFHOOK | |
2611 | (section_type_flags, | |
673c2f63 JM |
2612 | "Choose a set of section attributes for use by @code{TARGET_ASM_NAMED_SECTION}\n\ |
2613 | based on a variable or function decl, a section name, and whether or not the\n\ | |
2614 | declaration's initializer may contain runtime relocations. @var{decl} may be\n\ | |
2615 | null, in which case read-write data should be assumed.\n\ | |
2616 | \n\ | |
2617 | The default version of this function handles choosing code vs data,\n\ | |
2618 | read-only vs read-write data, and @code{flag_pic}. You should only\n\ | |
2619 | need to override this if your target has special flags that might be\n\ | |
2620 | set via @code{__attribute__}.", | |
38f8b050 JR |
2621 | unsigned int, (tree decl, const char *name, int reloc), |
2622 | default_section_type_flags) | |
2623 | ||
d33d9e47 AI |
2624 | DEFHOOK |
2625 | (libc_has_function, | |
2626 | "This hook determines whether a function from a class of functions\n\ | |
bae974e6 TV |
2627 | @var{fn_class} is present in the target C library. If @var{type} is NULL,\n\ |
2628 | the caller asks for support for all standard (float, double, long double)\n\ | |
2629 | types. If @var{type} is non-NULL, the caller asks for support for a\n\ | |
2630 | specific type.", | |
2631 | bool, (enum function_class fn_class, tree type), | |
d33d9e47 AI |
2632 | default_libc_has_function) |
2633 | ||
db91c7cf ML |
2634 | DEFHOOK |
2635 | (libc_has_fast_function, | |
2636 | "This hook determines whether a function from a class of functions\n\ | |
c53bb876 | 2637 | @code{(enum function_class)}@var{fcode} has a fast implementation.", |
db91c7cf ML |
2638 | bool, (int fcode), |
2639 | default_libc_has_fast_function) | |
2640 | ||
38f8b050 JR |
2641 | /* True if new jumps cannot be created, to replace existing ones or |
2642 | not, at the current point in the compilation. */ | |
2643 | DEFHOOK | |
2644 | (cannot_modify_jumps_p, | |
673c2f63 JM |
2645 | "This target hook returns @code{true} past the point in which new jump\n\ |
2646 | instructions could be created. On machines that require a register for\n\ | |
2647 | every jump such as the SHmedia ISA of SH5, this point would typically be\n\ | |
2648 | reload, so this target hook should be defined to a function such as:\n\ | |
2649 | \n\ | |
2650 | @smallexample\n\ | |
2651 | static bool\n\ | |
2652 | cannot_modify_jumps_past_reload_p ()\n\ | |
2653 | @{\n\ | |
2654 | return (reload_completed || reload_in_progress);\n\ | |
2655 | @}\n\ | |
2656 | @end smallexample", | |
38f8b050 JR |
2657 | bool, (void), |
2658 | hook_bool_void_false) | |
2659 | ||
4b4de898 JR |
2660 | /* True if FOLLOWER may be modified to follow FOLLOWEE. */ |
2661 | DEFHOOK | |
2662 | (can_follow_jump, | |
4d3907c2 ML |
2663 | "FOLLOWER and FOLLOWEE are JUMP_INSN instructions;\n\ |
2664 | return true if FOLLOWER may be modified to follow FOLLOWEE;\n\ | |
2665 | false, if it can't.\n\ | |
2666 | For example, on some targets, certain kinds of branches can't be made to\n\ | |
2667 | follow through a hot/cold partitioning.", | |
c1ce59ab DM |
2668 | bool, (const rtx_insn *follower, const rtx_insn *followee), |
2669 | hook_bool_const_rtx_insn_const_rtx_insn_true) | |
4b4de898 | 2670 | |
38f8b050 JR |
2671 | /* Return true if the target supports conditional execution. */ |
2672 | DEFHOOK | |
2673 | (have_conditional_execution, | |
673c2f63 JM |
2674 | "This target hook returns true if the target supports conditional execution.\n\ |
2675 | This target hook is required only when the target has several different\n\ | |
2676 | modes and they have different conditional execution capability, such as ARM.", | |
38f8b050 JR |
2677 | bool, (void), |
2678 | default_have_conditional_execution) | |
2679 | ||
2e0f1341 ZC |
2680 | DEFHOOK |
2681 | (gen_ccmp_first, | |
5f3bc026 | 2682 | "This function prepares to emit a comparison insn for the first compare in a\n\ |
c8012fbc WD |
2683 | sequence of conditional comparisions. It returns an appropriate comparison\n\ |
2684 | with @code{CC} for passing to @code{gen_ccmp_next} or @code{cbranch_optab}.\n\ | |
2685 | The insns to prepare the compare are saved in @var{prep_seq} and the compare\n\ | |
2686 | insns are saved in @var{gen_seq}. They will be emitted when all the\n\ | |
700d4cb0 | 2687 | compares in the conditional comparision are generated without error.\n\ |
c8012fbc | 2688 | @var{code} is the @code{rtx_code} of the compare for @var{op0} and @var{op1}.", |
cb4347e8 | 2689 | rtx, (rtx_insn **prep_seq, rtx_insn **gen_seq, int code, tree op0, tree op1), |
2e0f1341 ZC |
2690 | NULL) |
2691 | ||
2692 | DEFHOOK | |
2693 | (gen_ccmp_next, | |
c8012fbc WD |
2694 | "This function prepares to emit a conditional comparison within a sequence\n\ |
2695 | of conditional comparisons. It returns an appropriate comparison with\n\ | |
2696 | @code{CC} for passing to @code{gen_ccmp_next} or @code{cbranch_optab}.\n\ | |
2697 | The insns to prepare the compare are saved in @var{prep_seq} and the compare\n\ | |
2698 | insns are saved in @var{gen_seq}. They will be emitted when all the\n\ | |
2699 | compares in the conditional comparision are generated without error. The\n\ | |
2700 | @var{prev} expression is the result of a prior call to @code{gen_ccmp_first}\n\ | |
2701 | or @code{gen_ccmp_next}. It may return @code{NULL} if the combination of\n\ | |
2702 | @var{prev} and this comparison is not supported, otherwise the result must\n\ | |
2703 | be appropriate for passing to @code{gen_ccmp_next} or @code{cbranch_optab}.\n\ | |
2704 | @var{code} is the @code{rtx_code} of the compare for @var{op0} and @var{op1}.\n\ | |
2705 | @var{bit_code} is @code{AND} or @code{IOR}, which is the op on the compares.", | |
cb4347e8 | 2706 | rtx, (rtx_insn **prep_seq, rtx_insn **gen_seq, rtx prev, int cmp_code, tree op0, tree op1, int bit_code), |
2e0f1341 ZC |
2707 | NULL) |
2708 | ||
e5e164ef L |
2709 | DEFHOOK |
2710 | (gen_memset_scratch_rtx, | |
2711 | "This hook should return an rtx for a scratch register in @var{mode} to\n\ | |
2712 | be used when expanding memset calls. The backend can use a hard scratch\n\ | |
2713 | register to avoid stack realignment when expanding memset. The default\n\ | |
2714 | is @code{gen_reg_rtx}.", | |
2715 | rtx, (machine_mode mode), | |
2716 | gen_reg_rtx) | |
2717 | ||
38f8b050 JR |
2718 | /* Return a new value for loop unroll size. */ |
2719 | DEFHOOK | |
2720 | (loop_unroll_adjust, | |
673c2f63 JM |
2721 | "This target hook returns a new value for the number of times @var{loop}\n\ |
2722 | should be unrolled. The parameter @var{nunroll} is the number of times\n\ | |
2723 | the loop is to be unrolled. The parameter @var{loop} is a pointer to\n\ | |
2724 | the loop, which is going to be checked for unrolling. This target hook\n\ | |
2725 | is required only when the target has special constraints like maximum\n\ | |
2726 | number of memory accesses.", | |
99b1c316 | 2727 | unsigned, (unsigned nunroll, class loop *loop), |
38f8b050 JR |
2728 | NULL) |
2729 | ||
1a627b35 RS |
2730 | /* True if X is a legitimate MODE-mode immediate operand. */ |
2731 | DEFHOOK | |
2732 | (legitimate_constant_p, | |
673c2f63 JM |
2733 | "This hook returns true if @var{x} is a legitimate constant for a\n\ |
2734 | @var{mode}-mode immediate operand on the target machine. You can assume that\n\ | |
2735 | @var{x} satisfies @code{CONSTANT_P}, so you need not check this.\n\ | |
2736 | \n\ | |
2737 | The default definition returns true.", | |
ef4bddc2 | 2738 | bool, (machine_mode mode, rtx x), |
1a627b35 RS |
2739 | hook_bool_mode_rtx_true) |
2740 | ||
a21b3997 DE |
2741 | /* True if X is a TLS operand whose value should be pre-computed. */ |
2742 | DEFHOOK | |
2743 | (precompute_tls_p, | |
2744 | "This hook returns true if @var{x} is a TLS operand on the target\n\ | |
2745 | machine that should be pre-computed when used as the argument in a call.\n\ | |
2746 | You can assume that @var{x} satisfies @code{CONSTANT_P}, so you need not \n\ | |
2747 | check this.\n\ | |
2748 | \n\ | |
2749 | The default definition returns false.", | |
2750 | bool, (machine_mode mode, rtx x), | |
2751 | hook_bool_mode_rtx_false) | |
2752 | ||
38f8b050 JR |
2753 | /* True if the constant X cannot be placed in the constant pool. */ |
2754 | DEFHOOK | |
2755 | (cannot_force_const_mem, | |
673c2f63 JM |
2756 | "This hook should return true if @var{x} is of a form that cannot (or\n\ |
2757 | should not) be spilled to the constant pool. @var{mode} is the mode\n\ | |
2758 | of @var{x}.\n\ | |
2759 | \n\ | |
2760 | The default version of this hook returns false.\n\ | |
2761 | \n\ | |
2762 | The primary reason to define this hook is to prevent reload from\n\ | |
2763 | deciding that a non-legitimate constant would be better reloaded\n\ | |
2764 | from the constant pool instead of spilling and reloading a register\n\ | |
2765 | holding the constant. This restriction is often true of addresses\n\ | |
2766 | of TLS symbols for various targets.", | |
ef4bddc2 | 2767 | bool, (machine_mode mode, rtx x), |
fbbf66e7 | 2768 | hook_bool_mode_rtx_false) |
38f8b050 JR |
2769 | |
2770 | DEFHOOK_UNDOC | |
2771 | (cannot_copy_insn_p, | |
2772 | "True if the insn @var{x} cannot be duplicated.", | |
ac44248e | 2773 | bool, (rtx_insn *), NULL) |
38f8b050 JR |
2774 | |
2775 | /* True if X is considered to be commutative. */ | |
2776 | DEFHOOK | |
2777 | (commutative_p, | |
673c2f63 JM |
2778 | "This target hook returns @code{true} if @var{x} is considered to be commutative.\n\ |
2779 | Usually, this is just COMMUTATIVE_P (@var{x}), but the HP PA doesn't consider\n\ | |
2780 | PLUS to be commutative inside a MEM@. @var{outer_code} is the rtx code\n\ | |
2781 | of the enclosing rtl, if known, otherwise it is UNKNOWN.", | |
38f8b050 JR |
2782 | bool, (const_rtx x, int outer_code), |
2783 | hook_bool_const_rtx_commutative_p) | |
2784 | ||
2785 | /* True if ADDR is an address-expression whose effect depends | |
2786 | on the mode of the memory reference it is used in. */ | |
2787 | DEFHOOK | |
2788 | (mode_dependent_address_p, | |
673c2f63 JM |
2789 | "This hook returns @code{true} if memory address @var{addr} in address\n\ |
2790 | space @var{addrspace} can have\n\ | |
2791 | different meanings depending on the machine mode of the memory\n\ | |
2792 | reference it is used for or if the address is valid for some modes\n\ | |
2793 | but not others.\n\ | |
2794 | \n\ | |
2795 | Autoincrement and autodecrement addresses typically have mode-dependent\n\ | |
2796 | effects because the amount of the increment or decrement is the size\n\ | |
2797 | of the operand being addressed. Some machines have other mode-dependent\n\ | |
2798 | addresses. Many RISC machines have no mode-dependent addresses.\n\ | |
2799 | \n\ | |
2800 | You may assume that @var{addr} is a valid address for the machine.\n\ | |
2801 | \n\ | |
2802 | The default version of this hook returns @code{false}.", | |
5bfed9a9 | 2803 | bool, (const_rtx addr, addr_space_t addrspace), |
38f8b050 JR |
2804 | default_mode_dependent_address_p) |
2805 | ||
2806 | /* Given an invalid address X for a given machine mode, try machine-specific | |
2807 | ways to make it legitimate. Return X or an invalid address on failure. */ | |
2808 | DEFHOOK | |
2809 | (legitimize_address, | |
673c2f63 JM |
2810 | "This hook is given an invalid memory address @var{x} for an\n\ |
2811 | operand of mode @var{mode} and should try to return a valid memory\n\ | |
2812 | address.\n\ | |
2813 | \n\ | |
2814 | @findex break_out_memory_refs\n\ | |
2815 | @var{x} will always be the result of a call to @code{break_out_memory_refs},\n\ | |
2816 | and @var{oldx} will be the operand that was given to that function to produce\n\ | |
2817 | @var{x}.\n\ | |
2818 | \n\ | |
2819 | The code of the hook should not alter the substructure of\n\ | |
2820 | @var{x}. If it transforms @var{x} into a more legitimate form, it\n\ | |
2821 | should return the new @var{x}.\n\ | |
2822 | \n\ | |
2823 | It is not necessary for this hook to come up with a legitimate address,\n\ | |
2824 | with the exception of native TLS addresses (@pxref{Emulated TLS}).\n\ | |
2825 | The compiler has standard ways of doing so in all cases. In fact, if\n\ | |
2826 | the target supports only emulated TLS, it\n\ | |
2827 | is safe to omit this hook or make it return @var{x} if it cannot find\n\ | |
2828 | a valid way to legitimize the address. But often a machine-dependent\n\ | |
2829 | strategy can generate better code.", | |
ef4bddc2 | 2830 | rtx, (rtx x, rtx oldx, machine_mode mode), |
38f8b050 JR |
2831 | default_legitimize_address) |
2832 | ||
2833 | /* Given an address RTX, undo the effects of LEGITIMIZE_ADDRESS. */ | |
2834 | DEFHOOK | |
2835 | (delegitimize_address, | |
673c2f63 JM |
2836 | "This hook is used to undo the possibly obfuscating effects of the\n\ |
2837 | @code{LEGITIMIZE_ADDRESS} and @code{LEGITIMIZE_RELOAD_ADDRESS} target\n\ | |
2838 | macros. Some backend implementations of these macros wrap symbol\n\ | |
2839 | references inside an @code{UNSPEC} rtx to represent PIC or similar\n\ | |
2840 | addressing modes. This target hook allows GCC's optimizers to understand\n\ | |
2841 | the semantics of these opaque @code{UNSPEC}s by converting them back\n\ | |
2842 | into their original form.", | |
38f8b050 JR |
2843 | rtx, (rtx x), |
2844 | delegitimize_mem_from_attrs) | |
2845 | ||
93bcc8c9 JJ |
2846 | /* Given an RTX, return true if it is not ok to emit it into debug info |
2847 | section. */ | |
2848 | DEFHOOK | |
2849 | (const_not_ok_for_debug_p, | |
673c2f63 JM |
2850 | "This hook should return true if @var{x} should not be emitted into\n\ |
2851 | debug sections.", | |
93bcc8c9 | 2852 | bool, (rtx x), |
6b10f174 | 2853 | default_const_not_ok_for_debug_p) |
93bcc8c9 | 2854 | |
38f8b050 JR |
2855 | /* Given an address RTX, say whether it is valid. */ |
2856 | DEFHOOK | |
2857 | (legitimate_address_p, | |
673c2f63 JM |
2858 | "A function that returns whether @var{x} (an RTX) is a legitimate memory\n\ |
2859 | address on the target machine for a memory operand of mode @var{mode}.\n\ | |
2860 | \n\ | |
2861 | Legitimate addresses are defined in two variants: a strict variant and a\n\ | |
2862 | non-strict one. The @var{strict} parameter chooses which variant is\n\ | |
2863 | desired by the caller.\n\ | |
2864 | \n\ | |
2865 | The strict variant is used in the reload pass. It must be defined so\n\ | |
2866 | that any pseudo-register that has not been allocated a hard register is\n\ | |
2867 | considered a memory reference. This is because in contexts where some\n\ | |
2868 | kind of register is required, a pseudo-register with no hard register\n\ | |
2869 | must be rejected. For non-hard registers, the strict variant should look\n\ | |
2870 | up the @code{reg_renumber} array; it should then proceed using the hard\n\ | |
2871 | register number in the array, or treat the pseudo as a memory reference\n\ | |
2872 | if the array holds @code{-1}.\n\ | |
2873 | \n\ | |
2874 | The non-strict variant is used in other passes. It must be defined to\n\ | |
2875 | accept all pseudo-registers in every context where some kind of\n\ | |
2876 | register is required.\n\ | |
2877 | \n\ | |
2878 | Normally, constant addresses which are the sum of a @code{symbol_ref}\n\ | |
2879 | and an integer are stored inside a @code{const} RTX to mark them as\n\ | |
2880 | constant. Therefore, there is no need to recognize such sums\n\ | |
2881 | specifically as legitimate addresses. Normally you would simply\n\ | |
2882 | recognize any @code{const} as legitimate.\n\ | |
2883 | \n\ | |
2884 | Usually @code{PRINT_OPERAND_ADDRESS} is not prepared to handle constant\n\ | |
2885 | sums that are not marked with @code{const}. It assumes that a naked\n\ | |
2886 | @code{plus} indicates indexing. If so, then you @emph{must} reject such\n\ | |
2887 | naked constant sums as illegitimate addresses, so that none of them will\n\ | |
2888 | be given to @code{PRINT_OPERAND_ADDRESS}.\n\ | |
2889 | \n\ | |
2890 | @cindex @code{TARGET_ENCODE_SECTION_INFO} and address validation\n\ | |
2891 | On some machines, whether a symbolic address is legitimate depends on\n\ | |
2892 | the section that the address refers to. On these machines, define the\n\ | |
2893 | target hook @code{TARGET_ENCODE_SECTION_INFO} to store the information\n\ | |
2894 | into the @code{symbol_ref}, and then check for it here. When you see a\n\ | |
2895 | @code{const}, you will have to look inside it to find the\n\ | |
2896 | @code{symbol_ref} in order to determine the section. @xref{Assembler\n\ | |
2897 | Format}.\n\ | |
2898 | \n\ | |
2899 | @cindex @code{GO_IF_LEGITIMATE_ADDRESS}\n\ | |
2900 | Some ports are still using a deprecated legacy substitute for\n\ | |
2901 | this hook, the @code{GO_IF_LEGITIMATE_ADDRESS} macro. This macro\n\ | |
2902 | has this syntax:\n\ | |
2903 | \n\ | |
2904 | @example\n\ | |
2905 | #define GO_IF_LEGITIMATE_ADDRESS (@var{mode}, @var{x}, @var{label})\n\ | |
2906 | @end example\n\ | |
2907 | \n\ | |
2908 | @noindent\n\ | |
2909 | and should @code{goto @var{label}} if the address @var{x} is a valid\n\ | |
2910 | address on the target machine for a memory operand of mode @var{mode}.\n\ | |
2911 | \n\ | |
2912 | @findex REG_OK_STRICT\n\ | |
2913 | Compiler source files that want to use the strict variant of this\n\ | |
2914 | macro define the macro @code{REG_OK_STRICT}. You should use an\n\ | |
2915 | @code{#ifdef REG_OK_STRICT} conditional to define the strict variant in\n\ | |
2916 | that case and the non-strict variant otherwise.\n\ | |
2917 | \n\ | |
2918 | Using the hook is usually simpler because it limits the number of\n\ | |
2919 | files that are recompiled when changes are made.", | |
ef4bddc2 | 2920 | bool, (machine_mode mode, rtx x, bool strict), |
38f8b050 JR |
2921 | default_legitimate_address_p) |
2922 | ||
2923 | /* True if the given constant can be put into an object_block. */ | |
2924 | DEFHOOK | |
2925 | (use_blocks_for_constant_p, | |
673c2f63 JM |
2926 | "This hook should return true if pool entries for constant @var{x} can\n\ |
2927 | be placed in an @code{object_block} structure. @var{mode} is the mode\n\ | |
2928 | of @var{x}.\n\ | |
2929 | \n\ | |
2930 | The default version returns false for all constants.", | |
ef4bddc2 | 2931 | bool, (machine_mode mode, const_rtx x), |
38f8b050 JR |
2932 | hook_bool_mode_const_rtx_false) |
2933 | ||
361a58da DE |
2934 | /* True if the given decl can be put into an object_block. */ |
2935 | DEFHOOK | |
2936 | (use_blocks_for_decl_p, | |
673c2f63 JM |
2937 | "This hook should return true if pool entries for @var{decl} should\n\ |
2938 | be placed in an @code{object_block} structure.\n\ | |
2939 | \n\ | |
2940 | The default version returns true for all decls.", | |
361a58da DE |
2941 | bool, (const_tree decl), |
2942 | hook_bool_const_tree_true) | |
2943 | ||
38f8b050 JR |
2944 | /* The minimum and maximum byte offsets for anchored addresses. */ |
2945 | DEFHOOKPOD | |
2946 | (min_anchor_offset, | |
673c2f63 JM |
2947 | "The minimum offset that should be applied to a section anchor.\n\ |
2948 | On most targets, it should be the smallest offset that can be\n\ | |
2949 | applied to a base register while still giving a legitimate address\n\ | |
2950 | for every mode. The default value is 0.", | |
38f8b050 JR |
2951 | HOST_WIDE_INT, 0) |
2952 | ||
2953 | DEFHOOKPOD | |
2954 | (max_anchor_offset, | |
673c2f63 JM |
2955 | "Like @code{TARGET_MIN_ANCHOR_OFFSET}, but the maximum (inclusive)\n\ |
2956 | offset that should be applied to section anchors. The default\n\ | |
2957 | value is 0.", | |
38f8b050 JR |
2958 | HOST_WIDE_INT, 0) |
2959 | ||
2960 | /* True if section anchors can be used to access the given symbol. */ | |
2961 | DEFHOOK | |
2962 | (use_anchors_for_symbol_p, | |
673c2f63 JM |
2963 | "Return true if GCC should attempt to use anchors to access @code{SYMBOL_REF}\n\ |
2964 | @var{x}. You can assume @samp{SYMBOL_REF_HAS_BLOCK_INFO_P (@var{x})} and\n\ | |
2965 | @samp{!SYMBOL_REF_ANCHOR_P (@var{x})}.\n\ | |
2966 | \n\ | |
2967 | The default version is correct for most targets, but you might need to\n\ | |
2968 | intercept this hook to handle things like target-specific attributes\n\ | |
2969 | or target-specific sections.", | |
38f8b050 JR |
2970 | bool, (const_rtx x), |
2971 | default_use_anchors_for_symbol_p) | |
2972 | ||
2f251a05 AI |
2973 | /* True if target supports indirect functions. */ |
2974 | DEFHOOK | |
2975 | (has_ifunc_p, | |
2976 | "It returns true if the target supports GNU indirect functions.\n\ | |
2977 | The support includes the assembler, linker and dynamic linker.\n\ | |
2978 | The default value of this hook is based on target's libc.", | |
2979 | bool, (void), | |
2980 | default_has_ifunc_p) | |
2981 | ||
f7854b90 L |
2982 | /* True if it is OK to reference indirect function resolvers locally. */ |
2983 | DEFHOOK | |
2984 | (ifunc_ref_local_ok, | |
2985 | "Return true if it is OK to reference indirect function resolvers\n\ | |
2986 | locally. The default is to return false.", | |
2987 | bool, (void), | |
2988 | hook_bool_void_false) | |
2989 | ||
38f8b050 JR |
2990 | /* True if it is OK to do sibling call optimization for the specified |
2991 | call expression EXP. DECL will be the called function, or NULL if | |
2992 | this is an indirect call. */ | |
2993 | DEFHOOK | |
2994 | (function_ok_for_sibcall, | |
5bd40ade | 2995 | "True if it is OK to do sibling call optimization for the specified\n\ |
673c2f63 JM |
2996 | call expression @var{exp}. @var{decl} will be the called function,\n\ |
2997 | or @code{NULL} if this is an indirect call.\n\ | |
2998 | \n\ | |
2999 | It is not uncommon for limitations of calling conventions to prevent\n\ | |
3000 | tail calls to functions outside the current unit of translation, or\n\ | |
3001 | during PIC compilation. The hook is used to enforce these restrictions,\n\ | |
67914693 | 3002 | as the @code{sibcall} md pattern cannot fail, or fall over to a\n\ |
673c2f63 JM |
3003 | ``normal'' call. The criteria for successful sibling call optimization\n\ |
3004 | may vary greatly between different architectures.", | |
38f8b050 JR |
3005 | bool, (tree decl, tree exp), |
3006 | hook_bool_tree_tree_false) | |
3007 | ||
3008 | /* Establish appropriate back-end context for processing the function | |
3009 | FNDECL. The argument might be NULL to indicate processing at top | |
3010 | level, outside of any function scope. */ | |
3011 | DEFHOOK | |
3012 | (set_current_function, | |
673c2f63 JM |
3013 | "The compiler invokes this hook whenever it changes its current function\n\ |
3014 | context (@code{cfun}). You can define this function if\n\ | |
3015 | the back end needs to perform any initialization or reset actions on a\n\ | |
3016 | per-function basis. For example, it may be used to implement function\n\ | |
3017 | attributes that affect register usage or code generation patterns.\n\ | |
3018 | The argument @var{decl} is the declaration for the new function context,\n\ | |
3019 | and may be null to indicate that the compiler has left a function context\n\ | |
3020 | and is returning to processing at the top level.\n\ | |
3021 | The default hook function does nothing.\n\ | |
3022 | \n\ | |
3023 | GCC sets @code{cfun} to a dummy function context during initialization of\n\ | |
3024 | some parts of the back end. The hook function is not invoked in this\n\ | |
3025 | situation; you need not worry about the hook being invoked recursively,\n\ | |
3026 | or when the back end is in a partially-initialized state.\n\ | |
3027 | @code{cfun} might be @code{NULL} to indicate processing at top level,\n\ | |
3028 | outside of any function scope.", | |
38f8b050 JR |
3029 | void, (tree decl), hook_void_tree) |
3030 | ||
3031 | /* True if EXP should be placed in a "small data" section. */ | |
3032 | DEFHOOK | |
3033 | (in_small_data_p, | |
673c2f63 JM |
3034 | "Returns true if @var{exp} should be placed into a ``small data'' section.\n\ |
3035 | The default version of this hook always returns false.", | |
38f8b050 JR |
3036 | bool, (const_tree exp), |
3037 | hook_bool_const_tree_false) | |
3038 | ||
3039 | /* True if EXP names an object for which name resolution must resolve | |
3040 | to the current executable or shared library. */ | |
3041 | DEFHOOK | |
3042 | (binds_local_p, | |
673c2f63 JM |
3043 | "Returns true if @var{exp} names an object for which name resolution\n\ |
3044 | rules must resolve to the current ``module'' (dynamic shared library\n\ | |
3045 | or executable image).\n\ | |
3046 | \n\ | |
3047 | The default version of this hook implements the name resolution rules\n\ | |
3048 | for ELF, which has a looser model of global name binding than other\n\ | |
3049 | currently supported object file formats.", | |
38f8b050 JR |
3050 | bool, (const_tree exp), |
3051 | default_binds_local_p) | |
3052 | ||
3c5273a9 KT |
3053 | /* Check if profiling code is before or after prologue. */ |
3054 | DEFHOOK | |
3055 | (profile_before_prologue, | |
3056 | "It returns true if target wants profile code emitted before prologue.\n\n\ | |
3057 | The default version of this hook use the target macro\n\ | |
3058 | @code{PROFILE_BEFORE_PROLOGUE}.", | |
3059 | bool, (void), | |
3060 | default_profile_before_prologue) | |
3061 | ||
d56a43a0 AK |
3062 | /* Return true if a leaf function should stay leaf even with profiling |
3063 | enabled. */ | |
3064 | DEFHOOK | |
3065 | (keep_leaf_when_profiled, | |
4d3907c2 ML |
3066 | "This target hook returns true if the target wants the leaf flag for\n\ |
3067 | the current function to stay true even if it calls mcount. This might\n\ | |
3068 | make sense for targets using the leaf flag only to determine whether a\n\ | |
3069 | stack frame needs to be generated or not and for which the call to\n\ | |
3070 | mcount is generated before the function prologue.", | |
d56a43a0 AK |
3071 | bool, (void), |
3072 | default_keep_leaf_when_profiled) | |
3073 | ||
38f8b050 JR |
3074 | /* Modify and return the identifier of a DECL's external name, |
3075 | originally identified by ID, as required by the target, | |
3076 | (eg, append @nn to windows32 stdcall function names). | |
3077 | The default is to return ID without modification. */ | |
3078 | DEFHOOK | |
3079 | (mangle_decl_assembler_name, | |
673c2f63 JM |
3080 | "Define this hook if you need to postprocess the assembler name generated\n\ |
3081 | by target-independent code. The @var{id} provided to this hook will be\n\ | |
3082 | the computed name (e.g., the macro @code{DECL_NAME} of the @var{decl} in C,\n\ | |
3083 | or the mangled name of the @var{decl} in C++). The return value of the\n\ | |
3084 | hook is an @code{IDENTIFIER_NODE} for the appropriate mangled name on\n\ | |
3085 | your target system. The default implementation of this hook just\n\ | |
3086 | returns the @var{id} provided.", | |
38f8b050 JR |
3087 | tree, (tree decl, tree id), |
3088 | default_mangle_decl_assembler_name) | |
3089 | ||
3090 | /* Do something target-specific to record properties of the DECL into | |
3091 | the associated SYMBOL_REF. */ | |
3092 | DEFHOOK | |
3093 | (encode_section_info, | |
673c2f63 JM |
3094 | "Define this hook if references to a symbol or a constant must be\n\ |
3095 | treated differently depending on something about the variable or\n\ | |
3096 | function named by the symbol (such as what section it is in).\n\ | |
3097 | \n\ | |
3098 | The hook is executed immediately after rtl has been created for\n\ | |
3099 | @var{decl}, which may be a variable or function declaration or\n\ | |
3100 | an entry in the constant pool. In either case, @var{rtl} is the\n\ | |
3101 | rtl in question. Do @emph{not} use @code{DECL_RTL (@var{decl})}\n\ | |
3102 | in this hook; that field may not have been initialized yet.\n\ | |
3103 | \n\ | |
3104 | In the case of a constant, it is safe to assume that the rtl is\n\ | |
3105 | a @code{mem} whose address is a @code{symbol_ref}. Most decls\n\ | |
3106 | will also have this form, but that is not guaranteed. Global\n\ | |
3107 | register variables, for instance, will have a @code{reg} for their\n\ | |
3108 | rtl. (Normally the right thing to do with such unusual rtl is\n\ | |
3109 | leave it alone.)\n\ | |
3110 | \n\ | |
3111 | The @var{new_decl_p} argument will be true if this is the first time\n\ | |
3112 | that @code{TARGET_ENCODE_SECTION_INFO} has been invoked on this decl. It will\n\ | |
3113 | be false for subsequent invocations, which will happen for duplicate\n\ | |
3114 | declarations. Whether or not anything must be done for the duplicate\n\ | |
3115 | declaration depends on whether the hook examines @code{DECL_ATTRIBUTES}.\n\ | |
3116 | @var{new_decl_p} is always true when the hook is called for a constant.\n\ | |
3117 | \n\ | |
3118 | @cindex @code{SYMBOL_REF_FLAG}, in @code{TARGET_ENCODE_SECTION_INFO}\n\ | |
3119 | The usual thing for this hook to do is to record flags in the\n\ | |
3120 | @code{symbol_ref}, using @code{SYMBOL_REF_FLAG} or @code{SYMBOL_REF_FLAGS}.\n\ | |
3121 | Historically, the name string was modified if it was necessary to\n\ | |
3122 | encode more than one bit of information, but this practice is now\n\ | |
3123 | discouraged; use @code{SYMBOL_REF_FLAGS}.\n\ | |
3124 | \n\ | |
3125 | The default definition of this hook, @code{default_encode_section_info}\n\ | |
e53b6e56 | 3126 | in @file{varasm.cc}, sets a number of commonly-useful bits in\n\ |
673c2f63 JM |
3127 | @code{SYMBOL_REF_FLAGS}. Check whether the default does what you need\n\ |
3128 | before overriding it.", | |
38f8b050 JR |
3129 | void, (tree decl, rtx rtl, int new_decl_p), |
3130 | default_encode_section_info) | |
3131 | ||
3132 | /* Undo the effects of encode_section_info on the symbol string. */ | |
3133 | DEFHOOK | |
3134 | (strip_name_encoding, | |
673c2f63 JM |
3135 | "Decode @var{name} and return the real name part, sans\n\ |
3136 | the characters that @code{TARGET_ENCODE_SECTION_INFO}\n\ | |
3137 | may have added.", | |
38f8b050 JR |
3138 | const char *, (const char *name), |
3139 | default_strip_name_encoding) | |
3140 | ||
3141 | /* If shift optabs for MODE are known to always truncate the shift count, | |
3142 | return the mask that they apply. Return 0 otherwise. */ | |
3143 | DEFHOOK | |
3144 | (shift_truncation_mask, | |
673c2f63 JM |
3145 | "This function describes how the standard shift patterns for @var{mode}\n\ |
3146 | deal with shifts by negative amounts or by more than the width of the mode.\n\ | |
3147 | @xref{shift patterns}.\n\ | |
3148 | \n\ | |
3149 | On many machines, the shift patterns will apply a mask @var{m} to the\n\ | |
3150 | shift count, meaning that a fixed-width shift of @var{x} by @var{y} is\n\ | |
3151 | equivalent to an arbitrary-width shift of @var{x} by @var{y & m}. If\n\ | |
3152 | this is true for mode @var{mode}, the function should return @var{m},\n\ | |
3153 | otherwise it should return 0. A return value of 0 indicates that no\n\ | |
3154 | particular behavior is guaranteed.\n\ | |
3155 | \n\ | |
3156 | Note that, unlike @code{SHIFT_COUNT_TRUNCATED}, this function does\n\ | |
3157 | @emph{not} apply to general shift rtxes; it applies only to instructions\n\ | |
3158 | that are generated by the named shift patterns.\n\ | |
3159 | \n\ | |
3160 | The default implementation of this function returns\n\ | |
3161 | @code{GET_MODE_BITSIZE (@var{mode}) - 1} if @code{SHIFT_COUNT_TRUNCATED}\n\ | |
3162 | and 0 otherwise. This definition is always safe, but if\n\ | |
3163 | @code{SHIFT_COUNT_TRUNCATED} is false, and some shift patterns\n\ | |
3164 | nevertheless truncate the shift count, you may get better code\n\ | |
3165 | by overriding it.", | |
ef4bddc2 | 3166 | unsigned HOST_WIDE_INT, (machine_mode mode), |
38f8b050 JR |
3167 | default_shift_truncation_mask) |
3168 | ||
3169 | /* Return the number of divisions in the given MODE that should be present, | |
3170 | so that it is profitable to turn the division into a multiplication by | |
3171 | the reciprocal. */ | |
3172 | DEFHOOK | |
3173 | (min_divisions_for_recip_mul, | |
673c2f63 JM |
3174 | "When @option{-ffast-math} is in effect, GCC tries to optimize\n\ |
3175 | divisions by the same divisor, by turning them into multiplications by\n\ | |
3176 | the reciprocal. This target hook specifies the minimum number of divisions\n\ | |
3177 | that should be there for GCC to perform the optimization for a variable\n\ | |
3178 | of mode @var{mode}. The default implementation returns 3 if the machine\n\ | |
3179 | has an instruction for the division, and 2 if it does not.", | |
ef4bddc2 | 3180 | unsigned int, (machine_mode mode), |
38f8b050 JR |
3181 | default_min_divisions_for_recip_mul) |
3182 | ||
bb149ca2 RS |
3183 | DEFHOOK |
3184 | (truly_noop_truncation, | |
3185 | "This hook returns true if it is safe to ``convert'' a value of\n\ | |
3186 | @var{inprec} bits to one of @var{outprec} bits (where @var{outprec} is\n\ | |
3187 | smaller than @var{inprec}) by merely operating on it as if it had only\n\ | |
3188 | @var{outprec} bits. The default returns true unconditionally, which\n\ | |
5abe0d81 RS |
3189 | is correct for most machines. When @code{TARGET_TRULY_NOOP_TRUNCATION}\n\ |
3190 | returns false, the machine description should provide a @code{trunc}\n\ | |
3191 | optab to specify the RTL that performs the required truncation.\n\ | |
bb149ca2 RS |
3192 | \n\ |
3193 | If @code{TARGET_MODES_TIEABLE_P} returns false for a pair of modes,\n\ | |
3194 | suboptimal code can result if this hook returns true for the corresponding\n\ | |
3195 | mode sizes. Making this hook return false in such cases may improve things.", | |
37b2b8f9 RS |
3196 | bool, (poly_uint64 outprec, poly_uint64 inprec), |
3197 | hook_bool_puint64_puint64_true) | |
bb149ca2 | 3198 | |
38f8b050 JR |
3199 | /* If the representation of integral MODE is such that values are |
3200 | always sign-extended to a wider mode MODE_REP then return | |
3201 | SIGN_EXTEND. Return UNKNOWN otherwise. */ | |
3202 | /* Note that the return type ought to be RTX_CODE, but that's not | |
3203 | necessarily defined at this point. */ | |
3204 | DEFHOOK | |
3205 | (mode_rep_extended, | |
673c2f63 JM |
3206 | "The representation of an integral mode can be such that the values\n\ |
3207 | are always extended to a wider integral mode. Return\n\ | |
3208 | @code{SIGN_EXTEND} if values of @var{mode} are represented in\n\ | |
3209 | sign-extended form to @var{rep_mode}. Return @code{UNKNOWN}\n\ | |
3210 | otherwise. (Currently, none of the targets use zero-extended\n\ | |
3211 | representation this way so unlike @code{LOAD_EXTEND_OP},\n\ | |
3212 | @code{TARGET_MODE_REP_EXTENDED} is expected to return either\n\ | |
3213 | @code{SIGN_EXTEND} or @code{UNKNOWN}. Also no target extends\n\ | |
3214 | @var{mode} to @var{rep_mode} so that @var{rep_mode} is not the next\n\ | |
3215 | widest integral mode and currently we take advantage of this fact.)\n\ | |
3216 | \n\ | |
3217 | Similarly to @code{LOAD_EXTEND_OP} you may return a non-@code{UNKNOWN}\n\ | |
3218 | value even if the extension is not performed on certain hard registers\n\ | |
3219 | as long as for the @code{REGNO_REG_CLASS} of these hard registers\n\ | |
0d803030 | 3220 | @code{TARGET_CAN_CHANGE_MODE_CLASS} returns false.\n\ |
673c2f63 JM |
3221 | \n\ |
3222 | Note that @code{TARGET_MODE_REP_EXTENDED} and @code{LOAD_EXTEND_OP}\n\ | |
3223 | describe two related properties. If you define\n\ | |
3224 | @code{TARGET_MODE_REP_EXTENDED (mode, word_mode)} you probably also want\n\ | |
3225 | to define @code{LOAD_EXTEND_OP (mode)} to return the same type of\n\ | |
3226 | extension.\n\ | |
3227 | \n\ | |
3228 | In order to enforce the representation of @code{mode},\n\ | |
bb149ca2 | 3229 | @code{TARGET_TRULY_NOOP_TRUNCATION} should return false when truncating to\n\ |
673c2f63 | 3230 | @code{mode}.", |
095a2d76 | 3231 | int, (scalar_int_mode mode, scalar_int_mode rep_mode), |
38f8b050 JR |
3232 | default_mode_rep_extended) |
3233 | ||
4d3907c2 | 3234 | DEFHOOK |
82957a73 PB |
3235 | (setjmp_preserves_nonvolatile_regs_p, |
3236 | "On some targets, it is assumed that the compiler will spill all pseudos\n\ | |
3237 | that are live across a call to @code{setjmp}, while other targets treat\n\ | |
3238 | @code{setjmp} calls as normal function calls.\n\ | |
3239 | \n\ | |
3240 | This hook returns false if @code{setjmp} calls do not preserve all\n\ | |
3241 | non-volatile registers so that gcc that must spill all pseudos that are\n\ | |
3242 | live across @code{setjmp} calls. Define this to return true if the\n\ | |
3243 | target does not need to spill all pseudos live across @code{setjmp} calls.\n\ | |
3244 | The default implementation conservatively assumes all pseudos must be\n\ | |
3245 | spilled across @code{setjmp} calls.", | |
3246 | bool, (void), | |
3247 | hook_bool_void_false) | |
3248 | ||
38f8b050 JR |
3249 | /* True if MODE is valid for a pointer in __attribute__((mode("MODE"))). */ |
3250 | DEFHOOK | |
3251 | (valid_pointer_mode, | |
673c2f63 JM |
3252 | "Define this to return nonzero if the port can handle pointers\n\ |
3253 | with machine mode @var{mode}. The default version of this\n\ | |
3254 | hook returns true for both @code{ptr_mode} and @code{Pmode}.", | |
095a2d76 | 3255 | bool, (scalar_int_mode mode), |
38f8b050 JR |
3256 | default_valid_pointer_mode) |
3257 | ||
7352c013 RG |
3258 | /* Disambiguate with errno. */ |
3259 | DEFHOOK | |
3260 | (ref_may_alias_errno, | |
4d3907c2 ML |
3261 | "Define this to return nonzero if the memory reference @var{ref}\n\ |
3262 | may alias with the system C library errno location. The default\n\ | |
3263 | version of this hook assumes the system C library errno location\n\ | |
3264 | is either a declaration of type int or accessed by dereferencing\n\ | |
3265 | a pointer to int.", | |
99b1c316 | 3266 | bool, (ao_ref *ref), |
7352c013 RG |
3267 | default_ref_may_alias_errno) |
3268 | ||
38f8b050 JR |
3269 | /* Support for named address spaces. */ |
3270 | #undef HOOK_PREFIX | |
3271 | #define HOOK_PREFIX "TARGET_ADDR_SPACE_" | |
3272 | HOOK_VECTOR (TARGET_ADDR_SPACE_HOOKS, addr_space) | |
3273 | ||
3274 | /* MODE to use for a pointer into another address space. */ | |
3275 | DEFHOOK | |
3276 | (pointer_mode, | |
673c2f63 JM |
3277 | "Define this to return the machine mode to use for pointers to\n\ |
3278 | @var{address_space} if the target supports named address spaces.\n\ | |
0a798c16 | 3279 | The default version of this hook returns @code{ptr_mode}.", |
095a2d76 | 3280 | scalar_int_mode, (addr_space_t address_space), |
38f8b050 JR |
3281 | default_addr_space_pointer_mode) |
3282 | ||
3283 | /* MODE to use for an address in another address space. */ | |
3284 | DEFHOOK | |
3285 | (address_mode, | |
673c2f63 JM |
3286 | "Define this to return the machine mode to use for addresses in\n\ |
3287 | @var{address_space} if the target supports named address spaces.\n\ | |
0a798c16 | 3288 | The default version of this hook returns @code{Pmode}.", |
095a2d76 | 3289 | scalar_int_mode, (addr_space_t address_space), |
38f8b050 JR |
3290 | default_addr_space_address_mode) |
3291 | ||
3292 | /* True if MODE is valid for a pointer in __attribute__((mode("MODE"))) | |
3293 | in another address space. */ | |
3294 | DEFHOOK | |
3295 | (valid_pointer_mode, | |
673c2f63 JM |
3296 | "Define this to return nonzero if the port can handle pointers\n\ |
3297 | with machine mode @var{mode} to address space @var{as}. This target\n\ | |
3298 | hook is the same as the @code{TARGET_VALID_POINTER_MODE} target hook,\n\ | |
3299 | except that it includes explicit named address space support. The default\n\ | |
3300 | version of this hook returns true for the modes returned by either the\n\ | |
3301 | @code{TARGET_ADDR_SPACE_POINTER_MODE} or @code{TARGET_ADDR_SPACE_ADDRESS_MODE}\n\ | |
3302 | target hooks for the given address space.", | |
095a2d76 | 3303 | bool, (scalar_int_mode mode, addr_space_t as), |
38f8b050 JR |
3304 | default_addr_space_valid_pointer_mode) |
3305 | ||
3306 | /* True if an address is a valid memory address to a given named address | |
3307 | space for a given mode. */ | |
3308 | DEFHOOK | |
3309 | (legitimate_address_p, | |
673c2f63 JM |
3310 | "Define this to return true if @var{exp} is a valid address for mode\n\ |
3311 | @var{mode} in the named address space @var{as}. The @var{strict}\n\ | |
3312 | parameter says whether strict addressing is in effect after reload has\n\ | |
3313 | finished. This target hook is the same as the\n\ | |
3314 | @code{TARGET_LEGITIMATE_ADDRESS_P} target hook, except that it includes\n\ | |
3315 | explicit named address space support.", | |
ef4bddc2 | 3316 | bool, (machine_mode mode, rtx exp, bool strict, addr_space_t as), |
38f8b050 JR |
3317 | default_addr_space_legitimate_address_p) |
3318 | ||
3319 | /* Return an updated address to convert an invalid pointer to a named | |
3320 | address space to a valid one. If NULL_RTX is returned use machine | |
3321 | independent methods to make the address valid. */ | |
3322 | DEFHOOK | |
3323 | (legitimize_address, | |
673c2f63 JM |
3324 | "Define this to modify an invalid address @var{x} to be a valid address\n\ |
3325 | with mode @var{mode} in the named address space @var{as}. This target\n\ | |
3326 | hook is the same as the @code{TARGET_LEGITIMIZE_ADDRESS} target hook,\n\ | |
3327 | except that it includes explicit named address space support.", | |
ef4bddc2 | 3328 | rtx, (rtx x, rtx oldx, machine_mode mode, addr_space_t as), |
38f8b050 JR |
3329 | default_addr_space_legitimize_address) |
3330 | ||
3331 | /* True if one named address space is a subset of another named address. */ | |
3332 | DEFHOOK | |
3333 | (subset_p, | |
673c2f63 JM |
3334 | "Define this to return whether the @var{subset} named address space is\n\ |
3335 | contained within the @var{superset} named address space. Pointers to\n\ | |
3336 | a named address space that is a subset of another named address space\n\ | |
3337 | will be converted automatically without a cast if used together in\n\ | |
3338 | arithmetic operations. Pointers to a superset address space can be\n\ | |
3339 | converted to pointers to a subset address space via explicit casts.", | |
b5bcaa4a | 3340 | bool, (addr_space_t subset, addr_space_t superset), |
38f8b050 JR |
3341 | default_addr_space_subset_p) |
3342 | ||
6626f970 RH |
3343 | /* True if 0 is a valid address in the address space, or false if |
3344 | 0 is a NULL in the address space. */ | |
3345 | DEFHOOK | |
3346 | (zero_address_valid, | |
3347 | "Define this to modify the default handling of address 0 for the\n\ | |
3348 | address space. Return true if 0 should be considered a valid address.", | |
3349 | bool, (addr_space_t as), | |
3350 | default_addr_space_zero_address_valid) | |
3351 | ||
38f8b050 JR |
3352 | /* Function to convert an rtl expression from one address space to another. */ |
3353 | DEFHOOK | |
3354 | (convert, | |
673c2f63 JM |
3355 | "Define this to convert the pointer expression represented by the RTL\n\ |
3356 | @var{op} with type @var{from_type} that points to a named address\n\ | |
3357 | space to a new pointer expression with type @var{to_type} that points\n\ | |
3358 | to a different named address space. When this hook it called, it is\n\ | |
3359 | guaranteed that one of the two address spaces is a subset of the other,\n\ | |
3360 | as determined by the @code{TARGET_ADDR_SPACE_SUBSET_P} target hook.", | |
38f8b050 JR |
3361 | rtx, (rtx op, tree from_type, tree to_type), |
3362 | default_addr_space_convert) | |
3363 | ||
f736b911 RH |
3364 | /* Function to encode an address space into dwarf. */ |
3365 | DEFHOOK | |
3366 | (debug, | |
3367 | "Define this to define how the address space is encoded in dwarf.\n\ | |
3368 | The result is the value to be used with @code{DW_AT_address_class}.", | |
3369 | int, (addr_space_t as), | |
3370 | default_addr_space_debug) | |
3371 | ||
ffc22840 GJL |
3372 | /* Function to emit custom diagnostic if an address space is used. */ |
3373 | DEFHOOK | |
3374 | (diagnose_usage, | |
3375 | "Define this hook if the availability of an address space depends on\n\ | |
3376 | command line options and some diagnostics should be printed when the\n\ | |
3377 | address space is used. This hook is called during parsing and allows\n\ | |
3378 | to emit a better diagnostic compared to the case where the address space\n\ | |
3379 | was not registered with @code{c_register_addr_space}. @var{as} is\n\ | |
3380 | the address space as registered with @code{c_register_addr_space}.\n\ | |
3381 | @var{loc} is the location of the address space qualifier token.\n\ | |
3382 | The default implementation does nothing.", | |
3383 | void, (addr_space_t as, location_t loc), | |
3384 | default_addr_space_diagnose_usage) | |
3385 | ||
38f8b050 JR |
3386 | HOOK_VECTOR_END (addr_space) |
3387 | ||
3388 | #undef HOOK_PREFIX | |
3389 | #define HOOK_PREFIX "TARGET_" | |
3390 | ||
0a9d711d SP |
3391 | DEFHOOK |
3392 | (lower_local_decl_alignment, | |
3393 | "Define this hook to lower alignment of local, parm or result\n\ | |
3394 | decl @samp{(@var{decl})}.", | |
3395 | void, (tree decl), | |
3396 | hook_void_tree) | |
3397 | ||
f073de07 RS |
3398 | DEFHOOK |
3399 | (static_rtx_alignment, | |
3400 | "This hook returns the preferred alignment in bits for a\n\ | |
3401 | statically-allocated rtx, such as a constant pool entry. @var{mode}\n\ | |
3402 | is the mode of the rtx. The default implementation returns\n\ | |
3403 | @samp{GET_MODE_ALIGNMENT (@var{mode})}.", | |
3404 | HOST_WIDE_INT, (machine_mode mode), | |
3405 | default_static_rtx_alignment) | |
3406 | ||
58e17cf8 RS |
3407 | DEFHOOK |
3408 | (constant_alignment, | |
3409 | "This hook returns the alignment in bits of a constant that is being\n\ | |
3410 | placed in memory. @var{constant} is the constant and @var{basic_align}\n\ | |
3411 | is the alignment that the object would ordinarily have.\n\ | |
3412 | \n\ | |
3413 | The default definition just returns @var{basic_align}.\n\ | |
3414 | \n\ | |
3415 | The typical use of this hook is to increase alignment for string\n\ | |
3416 | constants to be word aligned so that @code{strcpy} calls that copy\n\ | |
3417 | constants can be done inline. The function\n\ | |
3418 | @code{constant_alignment_word_strings} provides such a definition.", | |
3419 | HOST_WIDE_INT, (const_tree constant, HOST_WIDE_INT basic_align), | |
3420 | default_constant_alignment) | |
3421 | ||
8de583fc PB |
3422 | DEFHOOK |
3423 | (translate_mode_attribute, | |
3424 | "Define this hook if during mode attribute processing, the port should\n\ | |
3425 | translate machine_mode @var{mode} to another mode. For example, rs6000's\n\ | |
3426 | @code{KFmode}, when it is the same as @code{TFmode}.\n\ | |
3427 | \n\ | |
3428 | The default version of the hook returns that mode that was passed in.", | |
3429 | machine_mode, (machine_mode mode), | |
3430 | default_translate_mode_attribute) | |
3431 | ||
38f8b050 JR |
3432 | /* True if MODE is valid for the target. By "valid", we mean able to |
3433 | be manipulated in non-trivial ways. In particular, this means all | |
3434 | the arithmetic is supported. */ | |
3435 | DEFHOOK | |
3436 | (scalar_mode_supported_p, | |
673c2f63 JM |
3437 | "Define this to return nonzero if the port is prepared to handle\n\ |
3438 | insns involving scalar mode @var{mode}. For a scalar mode to be\n\ | |
3439 | considered supported, all the basic arithmetic and comparisons\n\ | |
3440 | must work.\n\ | |
3441 | \n\ | |
3442 | The default version of this hook returns true for any mode\n\ | |
3443 | required to handle the basic C types (as defined by the port).\n\ | |
3444 | Included here are the double-word arithmetic supported by the\n\ | |
e53b6e56 | 3445 | code in @file{optabs.cc}.", |
18e2a8b8 | 3446 | bool, (scalar_mode mode), |
38f8b050 JR |
3447 | default_scalar_mode_supported_p) |
3448 | ||
3449 | /* Similarly for vector modes. "Supported" here is less strict. At | |
3450 | least some operations are supported; need to check optabs or builtins | |
3451 | for further details. */ | |
3452 | DEFHOOK | |
3453 | (vector_mode_supported_p, | |
673c2f63 JM |
3454 | "Define this to return nonzero if the port is prepared to handle\n\ |
3455 | insns involving vector mode @var{mode}. At the very least, it\n\ | |
3456 | must have move patterns for this mode.", | |
ef4bddc2 | 3457 | bool, (machine_mode mode), |
38f8b050 JR |
3458 | hook_bool_mode_false) |
3459 | ||
482b2b43 RS |
3460 | DEFHOOK |
3461 | (compatible_vector_types_p, | |
3462 | "Return true if there is no target-specific reason for treating\n\ | |
3463 | vector types @var{type1} and @var{type2} as distinct types. The caller\n\ | |
3464 | has already checked for target-independent reasons, meaning that the\n\ | |
3465 | types are known to have the same mode, to have the same number of elements,\n\ | |
3466 | and to have what the caller considers to be compatible element types.\n\ | |
3467 | \n\ | |
3468 | The main reason for defining this hook is to reject pairs of types\n\ | |
3469 | that are handled differently by the target's calling convention.\n\ | |
3470 | For example, when a new @var{N}-bit vector architecture is added\n\ | |
3471 | to a target, the target may want to handle normal @var{N}-bit\n\ | |
3472 | @code{VECTOR_TYPE} arguments and return values in the same way as\n\ | |
3473 | before, to maintain backwards compatibility. However, it may also\n\ | |
3474 | provide new, architecture-specific @code{VECTOR_TYPE}s that are passed\n\ | |
3475 | and returned in a more efficient way. It is then important to maintain\n\ | |
3476 | a distinction between the ``normal'' @code{VECTOR_TYPE}s and the new\n\ | |
3477 | architecture-specific ones.\n\ | |
3478 | \n\ | |
3479 | The default implementation returns true, which is correct for most targets.", | |
3480 | bool, (const_tree type1, const_tree type2), | |
3481 | hook_bool_const_tree_const_tree_true) | |
3482 | ||
5aea1e76 UW |
3483 | DEFHOOK |
3484 | (vector_alignment, | |
3485 | "This hook can be used to define the alignment for a vector of type\n\ | |
3486 | @var{type}, in order to comply with a platform ABI. The default is to\n\ | |
3487 | require natural alignment for vector types. The alignment returned by\n\ | |
3488 | this hook must be a power-of-two multiple of the default alignment of\n\ | |
3489 | the vector element type.", | |
3490 | HOST_WIDE_INT, (const_tree type), | |
3491 | default_vector_alignment) | |
3492 | ||
695da534 RS |
3493 | DEFHOOK |
3494 | (array_mode, | |
3495 | "Return the mode that GCC should use for an array that has\n\ | |
3496 | @var{nelems} elements, with each element having mode @var{mode}.\n\ | |
3497 | Return no mode if the target has no special requirements. In the\n\ | |
3498 | latter case, GCC looks for an integer mode of the appropriate size\n\ | |
3499 | if available and uses BLKmode otherwise. Usually the search for the\n\ | |
3500 | integer mode is limited to @code{MAX_FIXED_MODE_SIZE}, but the\n\ | |
3501 | @code{TARGET_ARRAY_MODE_SUPPORTED_P} hook allows a larger mode to be\n\ | |
3502 | used in specific cases.\n\ | |
3503 | \n\ | |
3504 | The main use of this hook is to specify that an array of vectors should\n\ | |
3505 | also have a vector mode. The default implementation returns no mode.", | |
3506 | opt_machine_mode, (machine_mode mode, unsigned HOST_WIDE_INT nelems), | |
3507 | hook_optmode_mode_uhwi_none) | |
3508 | ||
0f6d54f7 RS |
3509 | /* True if we should try to use a scalar mode to represent an array, |
3510 | overriding the usual MAX_FIXED_MODE limit. */ | |
3511 | DEFHOOK | |
3512 | (array_mode_supported_p, | |
3513 | "Return true if GCC should try to use a scalar mode to store an array\n\ | |
3514 | of @var{nelems} elements, given that each element has mode @var{mode}.\n\ | |
3515 | Returning true here overrides the usual @code{MAX_FIXED_MODE} limit\n\ | |
3516 | and allows GCC to use any defined integer mode.\n\ | |
3517 | \n\ | |
3518 | One use of this hook is to support vector load and store operations\n\ | |
3519 | that operate on several homogeneous vectors. For example, ARM NEON\n\ | |
3520 | has operations like:\n\ | |
3521 | \n\ | |
3522 | @smallexample\n\ | |
3523 | int8x8x3_t vld3_s8 (const int8_t *)\n\ | |
3524 | @end smallexample\n\ | |
3525 | \n\ | |
3526 | where the return type is defined as:\n\ | |
3527 | \n\ | |
3528 | @smallexample\n\ | |
3529 | typedef struct int8x8x3_t\n\ | |
3530 | @{\n\ | |
3531 | int8x8_t val[3];\n\ | |
3532 | @} int8x8x3_t;\n\ | |
3533 | @end smallexample\n\ | |
3534 | \n\ | |
3535 | If this hook allows @code{val} to have a scalar mode, then\n\ | |
3536 | @code{int8x8x3_t} can have the same mode. GCC can then store\n\ | |
3537 | @code{int8x8x3_t}s in registers rather than forcing them onto the stack.", | |
ef4bddc2 | 3538 | bool, (machine_mode mode, unsigned HOST_WIDE_INT nelems), |
0f6d54f7 RS |
3539 | hook_bool_mode_uhwi_false) |
3540 | ||
8cc4b7a2 JM |
3541 | DEFHOOK |
3542 | (libgcc_floating_mode_supported_p, | |
3543 | "Define this to return nonzero if libgcc provides support for the \n\ | |
3544 | floating-point mode @var{mode}, which is known to pass \n\ | |
3545 | @code{TARGET_SCALAR_MODE_SUPPORTED_P}. The default version of this \n\ | |
3546 | hook returns true for all of @code{SFmode}, @code{DFmode}, \n\ | |
3547 | @code{XFmode} and @code{TFmode}, if such modes exist.", | |
7c5bd57a | 3548 | bool, (scalar_float_mode mode), |
8cc4b7a2 JM |
3549 | default_libgcc_floating_mode_supported_p) |
3550 | ||
c65699ef JM |
3551 | DEFHOOK |
3552 | (floatn_mode, | |
3553 | "Define this to return the machine mode to use for the type \n\ | |
3554 | @code{_Float@var{n}}, if @var{extended} is false, or the type \n\ | |
1ce87609 RS |
3555 | @code{_Float@var{n}x}, if @var{extended} is true. If such a type is not\n\ |
3556 | supported, return @code{opt_scalar_float_mode ()}. The default version of\n\ | |
3557 | this hook returns @code{SFmode} for @code{_Float32}, @code{DFmode} for\n\ | |
c65699ef JM |
3558 | @code{_Float64} and @code{_Float32x} and @code{TFmode} for \n\ |
3559 | @code{_Float128}, if those modes exist and satisfy the requirements for \n\ | |
3560 | those types and pass @code{TARGET_SCALAR_MODE_SUPPORTED_P} and \n\ | |
3561 | @code{TARGET_LIBGCC_FLOATING_MODE_SUPPORTED_P}; for @code{_Float64x}, it \n\ | |
3562 | returns the first of @code{XFmode} and @code{TFmode} that exists and \n\ | |
3563 | satisfies the same requirements; for other types, it returns \n\ | |
1ce87609 RS |
3564 | @code{opt_scalar_float_mode ()}. The hook is only called for values\n\ |
3565 | of @var{n} and @var{extended} that are valid according to\n\ | |
3566 | ISO/IEC TS 18661-3:2015; that is, @var{n} is one of 32, 64, 128, or,\n\ | |
3567 | if @var{extended} is false, 16 or greater than 128 and a multiple of 32.", | |
3568 | opt_scalar_float_mode, (int n, bool extended), | |
c65699ef JM |
3569 | default_floatn_mode) |
3570 | ||
c6762423 MM |
3571 | DEFHOOK |
3572 | (floatn_builtin_p, | |
3573 | "Define this to return true if the @code{_Float@var{n}} and\n\ | |
3574 | @code{_Float@var{n}x} built-in functions should implicitly enable the\n\ | |
3575 | built-in function without the @code{__builtin_} prefix in addition to the\n\ | |
3576 | normal built-in function with the @code{__builtin_} prefix. The default is\n\ | |
3577 | to only enable built-in functions without the @code{__builtin_} prefix for\n\ | |
3578 | the GNU C langauge. In strict ANSI/ISO mode, the built-in function without\n\ | |
3579 | the @code{__builtin_} prefix is not enabled. The argument @code{FUNC} is the\n\ | |
3580 | @code{enum built_in_function} id of the function to be enabled.", | |
3581 | bool, (int func), | |
3582 | default_floatn_builtin_p) | |
3583 | ||
38f8b050 JR |
3584 | /* Compute cost of moving data from a register of class FROM to one of |
3585 | TO, using MODE. */ | |
3586 | DEFHOOK | |
3587 | (register_move_cost, | |
673c2f63 JM |
3588 | "This target hook should return the cost of moving data of mode @var{mode}\n\ |
3589 | from a register in class @var{from} to one in class @var{to}. The classes\n\ | |
3590 | are expressed using the enumeration values such as @code{GENERAL_REGS}.\n\ | |
3591 | A value of 2 is the default; other values are interpreted relative to\n\ | |
3592 | that.\n\ | |
3593 | \n\ | |
3594 | It is not required that the cost always equal 2 when @var{from} is the\n\ | |
3595 | same as @var{to}; on some machines it is expensive to move between\n\ | |
3596 | registers if they are not general registers.\n\ | |
3597 | \n\ | |
3598 | If reload sees an insn consisting of a single @code{set} between two\n\ | |
3599 | hard registers, and if @code{TARGET_REGISTER_MOVE_COST} applied to their\n\ | |
3600 | classes returns a value of 2, reload does not check to ensure that the\n\ | |
3601 | constraints of the insn are met. Setting a cost of other than 2 will\n\ | |
3602 | allow reload to verify that the constraints are met. You should do this\n\ | |
3603 | if the @samp{mov@var{m}} pattern's constraints do not allow such copying.\n\ | |
3604 | \n\ | |
3605 | The default version of this function returns 2.", | |
ef4bddc2 | 3606 | int, (machine_mode mode, reg_class_t from, reg_class_t to), |
38f8b050 JR |
3607 | default_register_move_cost) |
3608 | ||
3609 | /* Compute cost of moving registers to/from memory. */ | |
3610 | /* ??? Documenting the argument types for this hook requires a GFDL | |
3611 | license grant. Also, the documentation uses a different name for RCLASS. */ | |
911852ff | 3612 | DEFHOOK |
38f8b050 | 3613 | (memory_move_cost, |
673c2f63 JM |
3614 | "This target hook should return the cost of moving data of mode @var{mode}\n\ |
3615 | between a register of class @var{rclass} and memory; @var{in} is @code{false}\n\ | |
3616 | if the value is to be written to memory, @code{true} if it is to be read in.\n\ | |
3617 | This cost is relative to those in @code{TARGET_REGISTER_MOVE_COST}.\n\ | |
3618 | If moving between registers and memory is more expensive than between two\n\ | |
3619 | registers, you should add this target hook to express the relative cost.\n\ | |
3620 | \n\ | |
3621 | If you do not add this target hook, GCC uses a default cost of 4 plus\n\ | |
3622 | the cost of copying via a secondary reload register, if one is\n\ | |
3623 | needed. If your machine requires a secondary reload register to copy\n\ | |
3624 | between memory and a register of @var{rclass} but the reload mechanism is\n\ | |
3625 | more complex than copying via an intermediate, use this target hook to\n\ | |
3626 | reflect the actual cost of the move.\n\ | |
3627 | \n\ | |
3628 | GCC defines the function @code{memory_move_secondary_cost} if\n\ | |
3629 | secondary reloads are needed. It computes the costs due to copying via\n\ | |
3630 | a secondary register. If your machine copies from memory using a\n\ | |
3631 | secondary register in the conventional way but the default base value of\n\ | |
3632 | 4 is not correct for your machine, use this target hook to add some other\n\ | |
3633 | value to the result of that function. The arguments to that function\n\ | |
3634 | are the same as to this target hook.", | |
ef4bddc2 | 3635 | int, (machine_mode mode, reg_class_t rclass, bool in), |
38f8b050 JR |
3636 | default_memory_move_cost) |
3637 | ||
7cbed008 JG |
3638 | DEFHOOK |
3639 | (use_by_pieces_infrastructure_p, | |
3640 | "GCC will attempt several strategies when asked to copy between\n\ | |
3641 | two areas of memory, or to set, clear or store to memory, for example\n\ | |
3642 | when copying a @code{struct}. The @code{by_pieces} infrastructure\n\ | |
3643 | implements such memory operations as a sequence of load, store or move\n\ | |
3644 | insns. Alternate strategies are to expand the\n\ | |
76715c32 | 3645 | @code{cpymem} or @code{setmem} optabs, to emit a library call, or to emit\n\ |
7cbed008 JG |
3646 | unit-by-unit, loop-based operations.\n\ |
3647 | \n\ | |
3648 | This target hook should return true if, for a memory operation with a\n\ | |
3649 | given @var{size} and @var{alignment}, using the @code{by_pieces}\n\ | |
3650 | infrastructure is expected to result in better code generation.\n\ | |
3651 | Both @var{size} and @var{alignment} are measured in terms of storage\n\ | |
3652 | units.\n\ | |
3653 | \n\ | |
3654 | The parameter @var{op} is one of: @code{CLEAR_BY_PIECES},\n\ | |
36b85e43 BS |
3655 | @code{MOVE_BY_PIECES}, @code{SET_BY_PIECES}, @code{STORE_BY_PIECES} or\n\ |
3656 | @code{COMPARE_BY_PIECES}. These describe the type of memory operation\n\ | |
3657 | under consideration.\n\ | |
7cbed008 JG |
3658 | \n\ |
3659 | The parameter @var{speed_p} is true if the code is currently being\n\ | |
3660 | optimized for speed rather than size.\n\ | |
3661 | \n\ | |
3662 | Returning true for higher values of @var{size} can improve code generation\n\ | |
3663 | for speed if the target does not provide an implementation of the\n\ | |
76715c32 | 3664 | @code{cpymem} or @code{setmem} standard names, if the @code{cpymem} or\n\ |
7cbed008 JG |
3665 | @code{setmem} implementation would be more expensive than a sequence of\n\ |
3666 | insns, or if the overhead of a library call would dominate that of\n\ | |
3667 | the body of the memory operation.\n\ | |
3668 | \n\ | |
3669 | Returning true for higher values of @code{size} may also cause an increase\n\ | |
3670 | in code size, for example where the number of insns emitted to perform a\n\ | |
3671 | move would be greater than that of a library call.", | |
445d7826 | 3672 | bool, (unsigned HOST_WIDE_INT size, unsigned int alignment, |
7cbed008 JG |
3673 | enum by_pieces_operation op, bool speed_p), |
3674 | default_use_by_pieces_infrastructure_p) | |
3675 | ||
985b3a68 L |
3676 | DEFHOOK |
3677 | (overlap_op_by_pieces_p, | |
3678 | "This target hook should return true if when the @code{by_pieces}\n\ | |
3679 | infrastructure is used, an offset adjusted unaligned memory operation\n\ | |
3680 | in the smallest integer mode for the last piece operation of a memory\n\ | |
3681 | region can be generated to avoid doing more than one smaller operations.", | |
3682 | bool, (void), | |
3683 | hook_bool_void_false) | |
3684 | ||
36b85e43 BS |
3685 | DEFHOOK |
3686 | (compare_by_pieces_branch_ratio, | |
3687 | "When expanding a block comparison in MODE, gcc can try to reduce the\n\ | |
3688 | number of branches at the expense of more memory operations. This hook\n\ | |
3689 | allows the target to override the default choice. It should return the\n\ | |
3690 | factor by which branches should be reduced over the plain expansion with\n\ | |
3691 | one comparison per @var{mode}-sized piece. A port can also prevent a\n\ | |
3692 | particular mode from being used for block comparisons by returning a\n\ | |
3693 | negative number from this hook.", | |
3694 | int, (machine_mode mode), | |
3695 | default_compare_by_pieces_branch_ratio) | |
3696 | ||
e0bd6c9f RS |
3697 | DEFHOOK |
3698 | (slow_unaligned_access, | |
3699 | "This hook returns true if memory accesses described by the\n\ | |
3700 | @var{mode} and @var{alignment} parameters have a cost many times greater\n\ | |
3701 | than aligned accesses, for example if they are emulated in a trap handler.\n\ | |
630ba2fd | 3702 | This hook is invoked only for unaligned accesses, i.e.@: when\n\ |
e0bd6c9f RS |
3703 | @code{@var{alignment} < GET_MODE_ALIGNMENT (@var{mode})}.\n\ |
3704 | \n\ | |
3705 | When this hook returns true, the compiler will act as if\n\ | |
3706 | @code{STRICT_ALIGNMENT} were true when generating code for block\n\ | |
3707 | moves. This can cause significantly more instructions to be produced.\n\ | |
3708 | Therefore, do not make this hook return true if unaligned accesses only\n\ | |
3709 | add a cycle or two to the time for a memory access.\n\ | |
3710 | \n\ | |
3711 | The hook must return true whenever @code{STRICT_ALIGNMENT} is true.\n\ | |
3712 | The default implementation returns @code{STRICT_ALIGNMENT}.", | |
3713 | bool, (machine_mode mode, unsigned int align), | |
3714 | default_slow_unaligned_access) | |
3715 | ||
d95ab70a RS |
3716 | DEFHOOK |
3717 | (optab_supported_p, | |
3718 | "Return true if the optimizers should use optab @var{op} with\n\ | |
3719 | modes @var{mode1} and @var{mode2} for optimization type @var{opt_type}.\n\ | |
3720 | The optab is known to have an associated @file{.md} instruction\n\ | |
3721 | whose C condition is true. @var{mode2} is only meaningful for conversion\n\ | |
3722 | optabs; for direct optabs it is a copy of @var{mode1}.\n\ | |
3723 | \n\ | |
3724 | For example, when called with @var{op} equal to @code{rint_optab} and\n\ | |
3725 | @var{mode1} equal to @code{DFmode}, the hook should say whether the\n\ | |
3726 | optimizers should use optab @code{rintdf2}.\n\ | |
3727 | \n\ | |
3728 | The default hook returns true for all inputs.", | |
3729 | bool, (int op, machine_mode mode1, machine_mode mode2, | |
3730 | optimization_type opt_type), | |
3731 | default_optab_supported_p) | |
3732 | ||
38f8b050 JR |
3733 | /* True for MODE if the target expects that registers in this mode will |
3734 | be allocated to registers in a small register class. The compiler is | |
3735 | allowed to use registers explicitly used in the rtl as spill registers | |
3736 | but it should prevent extending the lifetime of these registers. */ | |
3737 | DEFHOOK | |
3738 | (small_register_classes_for_mode_p, | |
673c2f63 JM |
3739 | "Define this to return nonzero for machine modes for which the port has\n\ |
3740 | small register classes. If this target hook returns nonzero for a given\n\ | |
3741 | @var{mode}, the compiler will try to minimize the lifetime of registers\n\ | |
3742 | in @var{mode}. The hook may be called with @code{VOIDmode} as argument.\n\ | |
3743 | In this case, the hook is expected to return nonzero if it returns nonzero\n\ | |
3744 | for any mode.\n\ | |
3745 | \n\ | |
3746 | On some machines, it is risky to let hard registers live across arbitrary\n\ | |
3747 | insns. Typically, these machines have instructions that require values\n\ | |
3748 | to be in specific registers (like an accumulator), and reload will fail\n\ | |
3749 | if the required hard register is used for another purpose across such an\n\ | |
3750 | insn.\n\ | |
3751 | \n\ | |
3752 | Passes before reload do not know which hard registers will be used\n\ | |
3753 | in an instruction, but the machine modes of the registers set or used in\n\ | |
3754 | the instruction are already known. And for some machines, register\n\ | |
3755 | classes are small for, say, integer registers but not for floating point\n\ | |
3756 | registers. For example, the AMD x86-64 architecture requires specific\n\ | |
3757 | registers for the legacy x86 integer instructions, but there are many\n\ | |
3758 | SSE registers for floating point operations. On such targets, a good\n\ | |
3759 | strategy may be to return nonzero from this hook for @code{INTEGRAL_MODE_P}\n\ | |
3760 | machine modes but zero for the SSE register classes.\n\ | |
3761 | \n\ | |
3762 | The default version of this hook returns false for any mode. It is always\n\ | |
3763 | safe to redefine this hook to return with a nonzero value. But if you\n\ | |
3764 | unnecessarily define it, you will reduce the amount of optimizations\n\ | |
3765 | that can be performed in some cases. If you do not define this hook\n\ | |
3766 | to return a nonzero value when it is required, the compiler will run out\n\ | |
3767 | of spill registers and print a fatal error message.", | |
ef4bddc2 | 3768 | bool, (machine_mode mode), |
38f8b050 JR |
3769 | hook_bool_mode_false) |
3770 | ||
e692f276 RH |
3771 | /* Register number for a flags register. Only needs to be defined if the |
3772 | target is constrainted to use post-reload comparison elimination. */ | |
3773 | DEFHOOKPOD | |
3774 | (flags_regnum, | |
9adea939 HPN |
3775 | "If the target has a dedicated flags register, and it needs to use the\n\ |
3776 | post-reload comparison elimination pass, or the delay slot filler pass,\n\ | |
3777 | then this value should be set appropriately.", | |
3778 | unsigned int, INVALID_REGNUM) | |
e692f276 | 3779 | |
38f8b050 JR |
3780 | /* Compute a (partial) cost for rtx X. Return true if the complete |
3781 | cost has been computed, and false if subexpressions should be | |
3782 | scanned. In either case, *TOTAL contains the cost result. */ | |
e548c9df | 3783 | /* Note that OUTER_CODE ought to be RTX_CODE, but that's |
38f8b050 JR |
3784 | not necessarily defined at this point. */ |
3785 | DEFHOOK | |
3786 | (rtx_costs, | |
673c2f63 JM |
3787 | "This target hook describes the relative costs of RTL expressions.\n\ |
3788 | \n\ | |
3789 | The cost may depend on the precise form of the expression, which is\n\ | |
3790 | available for examination in @var{x}, and the fact that @var{x} appears\n\ | |
3791 | as operand @var{opno} of an expression with rtx code @var{outer_code}.\n\ | |
3792 | That is, the hook can assume that there is some rtx @var{y} such\n\ | |
3793 | that @samp{GET_CODE (@var{y}) == @var{outer_code}} and such that\n\ | |
3794 | either (a) @samp{XEXP (@var{y}, @var{opno}) == @var{x}} or\n\ | |
3795 | (b) @samp{XVEC (@var{y}, @var{opno})} contains @var{x}.\n\ | |
3796 | \n\ | |
e548c9df AM |
3797 | @var{mode} is @var{x}'s machine mode, or for cases like @code{const_int} that\n\ |
3798 | do not have a mode, the mode in which @var{x} is used.\n\ | |
673c2f63 JM |
3799 | \n\ |
3800 | In implementing this hook, you can use the construct\n\ | |
3801 | @code{COSTS_N_INSNS (@var{n})} to specify a cost equal to @var{n} fast\n\ | |
3802 | instructions.\n\ | |
3803 | \n\ | |
3804 | On entry to the hook, @code{*@var{total}} contains a default estimate\n\ | |
3805 | for the cost of the expression. The hook should modify this value as\n\ | |
3806 | necessary. Traditionally, the default costs are @code{COSTS_N_INSNS (5)}\n\ | |
3807 | for multiplications, @code{COSTS_N_INSNS (7)} for division and modulus\n\ | |
3808 | operations, and @code{COSTS_N_INSNS (1)} for all other operations.\n\ | |
3809 | \n\ | |
3810 | When optimizing for code size, i.e.@: when @code{speed} is\n\ | |
3811 | false, this target hook should be used to estimate the relative\n\ | |
3812 | size cost of an expression, again relative to @code{COSTS_N_INSNS}.\n\ | |
3813 | \n\ | |
3814 | The hook returns true when all subexpressions of @var{x} have been\n\ | |
3815 | processed, and false when @code{rtx_cost} should recurse.", | |
e548c9df AM |
3816 | bool, (rtx x, machine_mode mode, int outer_code, int opno, int *total, bool speed), |
3817 | hook_bool_rtx_mode_int_int_intp_bool_false) | |
38f8b050 JR |
3818 | |
3819 | /* Compute the cost of X, used as an address. Never called with | |
3820 | invalid addresses. */ | |
3821 | DEFHOOK | |
3822 | (address_cost, | |
673c2f63 JM |
3823 | "This hook computes the cost of an addressing mode that contains\n\ |
3824 | @var{address}. If not defined, the cost is computed from\n\ | |
3825 | the @var{address} expression and the @code{TARGET_RTX_COST} hook.\n\ | |
3826 | \n\ | |
3827 | For most CISC machines, the default cost is a good approximation of the\n\ | |
3828 | true cost of the addressing mode. However, on RISC machines, all\n\ | |
3829 | instructions normally have the same length and execution time. Hence\n\ | |
3830 | all addresses will have equal costs.\n\ | |
3831 | \n\ | |
3832 | In cases where more than one form of an address is known, the form with\n\ | |
3833 | the lowest cost will be used. If multiple forms have the same, lowest,\n\ | |
3834 | cost, the one that is the most complex will be used.\n\ | |
3835 | \n\ | |
3836 | For example, suppose an address that is equal to the sum of a register\n\ | |
3837 | and a constant is used twice in the same basic block. When this macro\n\ | |
3838 | is not defined, the address will be computed in a register and memory\n\ | |
3839 | references will be indirect through that register. On machines where\n\ | |
3840 | the cost of the addressing mode containing the sum is no higher than\n\ | |
3841 | that of a simple indirect reference, this will produce an additional\n\ | |
3842 | instruction and possibly require an additional register. Proper\n\ | |
3843 | specification of this macro eliminates this overhead for such machines.\n\ | |
3844 | \n\ | |
3845 | This hook is never called with an invalid address.\n\ | |
3846 | \n\ | |
3847 | On machines where an address involving more than one register is as\n\ | |
3848 | cheap as an address computation involving only one register, defining\n\ | |
3849 | @code{TARGET_ADDRESS_COST} to reflect this can cause two registers to\n\ | |
3850 | be live over a region of code where only one would have been if\n\ | |
3851 | @code{TARGET_ADDRESS_COST} were not defined in that manner. This effect\n\ | |
3852 | should be considered in the definition of this macro. Equivalent costs\n\ | |
3853 | should probably only be given to addresses with different numbers of\n\ | |
3854 | registers on machines with lots of registers.", | |
ef4bddc2 | 3855 | int, (rtx address, machine_mode mode, addr_space_t as, bool speed), |
38f8b050 JR |
3856 | default_address_cost) |
3857 | ||
94105f5c SB |
3858 | /* Compute a cost for INSN. */ |
3859 | DEFHOOK | |
3860 | (insn_cost, | |
3861 | "This target hook describes the relative costs of RTL instructions.\n\ | |
3862 | \n\ | |
3863 | In implementing this hook, you can use the construct\n\ | |
3864 | @code{COSTS_N_INSNS (@var{n})} to specify a cost equal to @var{n} fast\n\ | |
3865 | instructions.\n\ | |
3866 | \n\ | |
3867 | When optimizing for code size, i.e.@: when @code{speed} is\n\ | |
3868 | false, this target hook should be used to estimate the relative\n\ | |
3869 | size cost of an expression, again relative to @code{COSTS_N_INSNS}.", | |
3870 | int, (rtx_insn *insn, bool speed), NULL) | |
3871 | ||
e914c11a JG |
3872 | /* Give a cost, in RTX Costs units, for an edge. Like BRANCH_COST, but with |
3873 | well defined units. */ | |
3874 | DEFHOOK | |
3875 | (max_noce_ifcvt_seq_cost, | |
3876 | "This hook returns a value in the same units as @code{TARGET_RTX_COSTS},\n\ | |
3877 | giving the maximum acceptable cost for a sequence generated by the RTL\n\ | |
3878 | if-conversion pass when conditional execution is not available.\n\ | |
3879 | The RTL if-conversion pass attempts to convert conditional operations\n\ | |
3880 | that would require a branch to a series of unconditional operations and\n\ | |
3881 | @code{mov@var{mode}cc} insns. This hook returns the maximum cost of the\n\ | |
3882 | unconditional instructions and the @code{mov@var{mode}cc} insns.\n\ | |
3883 | RTL if-conversion is cancelled if the cost of the converted sequence\n\ | |
3884 | is greater than the value returned by this hook.\n\ | |
3885 | \n\ | |
3886 | @code{e} is the edge between the basic block containing the conditional\n\ | |
3887 | branch to the basic block which would be executed if the condition\n\ | |
3888 | were true.\n\ | |
3889 | \n\ | |
3890 | The default implementation of this hook uses the\n\ | |
3891 | @code{max-rtl-if-conversion-[un]predictable} parameters if they are set,\n\ | |
3892 | and uses a multiple of @code{BRANCH_COST} otherwise.", | |
3893 | unsigned int, (edge e), | |
3894 | default_max_noce_ifcvt_seq_cost) | |
3895 | ||
d16e2ddd JJ |
3896 | /* Return true if the given instruction sequence is a good candidate |
3897 | as a replacement for the if-convertible sequence. */ | |
3898 | DEFHOOK | |
3899 | (noce_conversion_profitable_p, | |
3900 | "This hook returns true if the instruction sequence @code{seq} is a good\n\ | |
3901 | candidate as a replacement for the if-convertible sequence described in\n\ | |
3902 | @code{if_info}.", | |
3903 | bool, (rtx_insn *seq, struct noce_if_info *if_info), | |
3904 | default_noce_conversion_profitable_p) | |
3905 | ||
de6320a8 CB |
3906 | /* Return true if new_addr should be preferred over the existing address used by |
3907 | memref in insn. */ | |
3908 | DEFHOOK | |
3909 | (new_address_profitable_p, | |
3910 | "Return @code{true} if it is profitable to replace the address in\n\ | |
3911 | @var{memref} with @var{new_addr}. This allows targets to prevent the\n\ | |
3912 | scheduler from undoing address optimizations. The instruction containing the\n\ | |
3913 | memref is @var{insn}. The default implementation returns @code{true}.", | |
3914 | bool, (rtx memref, rtx_insn * insn, rtx new_addr), | |
3915 | default_new_address_profitable_p) | |
3916 | ||
e535b963 RS |
3917 | DEFHOOK |
3918 | (estimated_poly_value, | |
3919 | "Return an estimate of the runtime value of @var{val}, for use in\n\ | |
64432b68 KT |
3920 | things like cost calculations or profiling frequencies. @var{kind} is used\n\ |
3921 | to ask for the minimum, maximum, and likely estimates of the value through\n\ | |
3922 | the @code{POLY_VALUE_MIN}, @code{POLY_VALUE_MAX} and\n\ | |
3923 | @code{POLY_VALUE_LIKELY} values. The default\n\ | |
e535b963 | 3924 | implementation returns the lowest possible value of @var{val}.", |
64432b68 | 3925 | HOST_WIDE_INT, (poly_int64 val, poly_value_estimate_kind kind), |
e535b963 RS |
3926 | default_estimated_poly_value) |
3927 | ||
f52a73a4 SD |
3928 | /* Permit speculative instructions in delay slots during delayed-branch |
3929 | scheduling. */ | |
3930 | DEFHOOK | |
3931 | (no_speculation_in_delay_slots_p, | |
3932 | "This predicate controls the use of the eager delay slot filler to disallow\n\ | |
3933 | speculatively executed instructions being placed in delay slots. Targets\n\ | |
3934 | such as certain MIPS architectures possess both branches with and without\n\ | |
3935 | delay slots. As the eager delay slot filler can decrease performance,\n\ | |
3936 | disabling it is beneficial when ordinary branches are available. Use of\n\ | |
3937 | delay slot branches filled using the basic filler is often still desirable\n\ | |
4d3907c2 ML |
3938 | as the delay slot can hide a pipeline bubble.", |
3939 | bool, (void), | |
f52a73a4 SD |
3940 | hook_bool_void_false) |
3941 | ||
38f8b050 JR |
3942 | /* Return where to allocate pseudo for a given hard register initial value. */ |
3943 | DEFHOOK | |
3944 | (allocate_initial_value, | |
673c2f63 JM |
3945 | "\n\ |
3946 | When the initial value of a hard register has been copied in a pseudo\n\ | |
3947 | register, it is often not necessary to actually allocate another register\n\ | |
3948 | to this pseudo register, because the original hard register or a stack slot\n\ | |
3949 | it has been saved into can be used. @code{TARGET_ALLOCATE_INITIAL_VALUE}\n\ | |
3950 | is called at the start of register allocation once for each hard register\n\ | |
3951 | that had its initial value copied by using\n\ | |
3952 | @code{get_func_hard_reg_initial_val} or @code{get_hard_reg_initial_val}.\n\ | |
3953 | Possible values are @code{NULL_RTX}, if you don't want\n\ | |
3954 | to do any special allocation, a @code{REG} rtx---that would typically be\n\ | |
3955 | the hard register itself, if it is known not to be clobbered---or a\n\ | |
3956 | @code{MEM}.\n\ | |
3957 | If you are returning a @code{MEM}, this is only a hint for the allocator;\n\ | |
3958 | it might decide to use another register anyways.\n\ | |
3959 | You may use @code{current_function_is_leaf} or \n\ | |
3960 | @code{REG_N_SETS} in the hook to determine if the hard\n\ | |
3961 | register in question will not be clobbered.\n\ | |
3962 | The default value of this hook is @code{NULL}, which disables any special\n\ | |
3963 | allocation.", | |
38f8b050 JR |
3964 | rtx, (rtx hard_reg), NULL) |
3965 | ||
c84a808e | 3966 | /* Return nonzero if evaluating UNSPEC X might cause a trap. |
e53b6e56 | 3967 | FLAGS has the same meaning as in rtlanal.cc: may_trap_p_1. */ |
38f8b050 JR |
3968 | DEFHOOK |
3969 | (unspec_may_trap_p, | |
673c2f63 JM |
3970 | "This target hook returns nonzero if @var{x}, an @code{unspec} or\n\ |
3971 | @code{unspec_volatile} operation, might cause a trap. Targets can use\n\ | |
3972 | this hook to enhance precision of analysis for @code{unspec} and\n\ | |
3973 | @code{unspec_volatile} operations. You may call @code{may_trap_p_1}\n\ | |
3974 | to analyze inner elements of @var{x} in which case @var{flags} should be\n\ | |
3975 | passed along.", | |
38f8b050 JR |
3976 | int, (const_rtx x, unsigned flags), |
3977 | default_unspec_may_trap_p) | |
3978 | ||
3979 | /* Given a register, this hook should return a parallel of registers | |
3980 | to represent where to find the register pieces. Define this hook | |
3981 | if the register and its mode are represented in Dwarf in | |
3982 | non-contiguous locations, or if the register should be | |
3983 | represented in more than one register in Dwarf. Otherwise, this | |
3984 | hook should return NULL_RTX. */ | |
3985 | DEFHOOK | |
3986 | (dwarf_register_span, | |
673c2f63 JM |
3987 | "Given a register, this hook should return a parallel of registers to\n\ |
3988 | represent where to find the register pieces. Define this hook if the\n\ | |
3989 | register and its mode are represented in Dwarf in non-contiguous\n\ | |
3990 | locations, or if the register should be represented in more than one\n\ | |
3991 | register in Dwarf. Otherwise, this hook should return @code{NULL_RTX}.\n\ | |
3992 | If not defined, the default is to return @code{NULL_RTX}.", | |
38f8b050 JR |
3993 | rtx, (rtx reg), |
3994 | hook_rtx_rtx_null) | |
3995 | ||
ff050c66 MF |
3996 | /* Given a register return the mode of the corresponding DWARF frame |
3997 | register. */ | |
3998 | DEFHOOK | |
3999 | (dwarf_frame_reg_mode, | |
4000 | "Given a register, this hook should return the mode which the\n\ | |
4001 | corresponding Dwarf frame register should have. This is normally\n\ | |
4002 | used to return a smaller mode than the raw mode to prevent call\n\ | |
4003 | clobbered parts of a register altering the frame register size", | |
ef4bddc2 | 4004 | machine_mode, (int regno), |
ff050c66 MF |
4005 | default_dwarf_frame_reg_mode) |
4006 | ||
38f8b050 JR |
4007 | /* If expand_builtin_init_dwarf_reg_sizes needs to fill in table |
4008 | entries not corresponding directly to registers below | |
4009 | FIRST_PSEUDO_REGISTER, this hook should generate the necessary | |
4010 | code, given the address of the table. */ | |
4011 | DEFHOOK | |
4012 | (init_dwarf_reg_sizes_extra, | |
673c2f63 JM |
4013 | "If some registers are represented in Dwarf-2 unwind information in\n\ |
4014 | multiple pieces, define this hook to fill in information about the\n\ | |
4015 | sizes of those pieces in the table used by the unwinder at runtime.\n\ | |
4016 | It will be called by @code{expand_builtin_init_dwarf_reg_sizes} after\n\ | |
4017 | filling in a single size corresponding to each hard register;\n\ | |
4018 | @var{address} is the address of the table.", | |
38f8b050 JR |
4019 | void, (tree address), |
4020 | hook_void_tree) | |
4021 | ||
4022 | /* Fetch the fixed register(s) which hold condition codes, for | |
4023 | targets where it makes sense to look for duplicate assignments to | |
4024 | the condition codes. This should return true if there is such a | |
4025 | register, false otherwise. The arguments should be set to the | |
4026 | fixed register numbers. Up to two condition code registers are | |
4027 | supported. If there is only one for this target, the int pointed | |
4028 | at by the second argument should be set to -1. */ | |
4029 | DEFHOOK | |
4030 | (fixed_condition_code_regs, | |
bd1cd0d0 | 4031 | "On targets which use a hard\n\ |
673c2f63 JM |
4032 | register rather than a pseudo-register to hold condition codes, the\n\ |
4033 | regular CSE passes are often not able to identify cases in which the\n\ | |
4034 | hard register is set to a common value. Use this hook to enable a\n\ | |
4035 | small pass which optimizes such cases. This hook should return true\n\ | |
4036 | to enable this pass, and it should set the integers to which its\n\ | |
4037 | arguments point to the hard register numbers used for condition codes.\n\ | |
4038 | When there is only one such register, as is true on most systems, the\n\ | |
4039 | integer pointed to by @var{p2} should be set to\n\ | |
4040 | @code{INVALID_REGNUM}.\n\ | |
4041 | \n\ | |
4042 | The default version of this hook returns false.", | |
38f8b050 JR |
4043 | bool, (unsigned int *p1, unsigned int *p2), |
4044 | hook_bool_uintp_uintp_false) | |
4045 | ||
4046 | /* If two condition code modes are compatible, return a condition | |
4047 | code mode which is compatible with both, such that a comparison | |
4048 | done in the returned mode will work for both of the original | |
4049 | modes. If the condition code modes are not compatible, return | |
4050 | VOIDmode. */ | |
4051 | DEFHOOK | |
4052 | (cc_modes_compatible, | |
673c2f63 JM |
4053 | "On targets which use multiple condition code modes in class\n\ |
4054 | @code{MODE_CC}, it is sometimes the case that a comparison can be\n\ | |
4055 | validly done in more than one mode. On such a system, define this\n\ | |
4056 | target hook to take two mode arguments and to return a mode in which\n\ | |
4057 | both comparisons may be validly done. If there is no such mode,\n\ | |
4058 | return @code{VOIDmode}.\n\ | |
4059 | \n\ | |
4060 | The default version of this hook checks whether the modes are the\n\ | |
4061 | same. If they are, it returns that mode. If they are different, it\n\ | |
4062 | returns @code{VOIDmode}.", | |
ef4bddc2 | 4063 | machine_mode, (machine_mode m1, machine_mode m2), |
38f8b050 JR |
4064 | default_cc_modes_compatible) |
4065 | ||
4066 | /* Do machine-dependent code transformations. Called just before | |
4067 | delayed-branch scheduling. */ | |
4068 | DEFHOOK | |
4069 | (machine_dependent_reorg, | |
673c2f63 JM |
4070 | "If non-null, this hook performs a target-specific pass over the\n\ |
4071 | instruction stream. The compiler will run it at all optimization levels,\n\ | |
4072 | just before the point at which it normally does delayed-branch scheduling.\n\ | |
4073 | \n\ | |
4074 | The exact purpose of the hook varies from target to target. Some use\n\ | |
4075 | it to do transformations that are necessary for correctness, such as\n\ | |
4076 | laying out in-function constant pools or avoiding hardware hazards.\n\ | |
4077 | Others use it as an opportunity to do some machine-dependent optimizations.\n\ | |
4078 | \n\ | |
4079 | You need not implement the hook if it has nothing to do. The default\n\ | |
4080 | definition is null.", | |
38f8b050 JR |
4081 | void, (void), NULL) |
4082 | ||
4083 | /* Create the __builtin_va_list type. */ | |
4084 | DEFHOOK | |
4085 | (build_builtin_va_list, | |
673c2f63 JM |
4086 | "This hook returns a type node for @code{va_list} for the target.\n\ |
4087 | The default version of the hook returns @code{void*}.", | |
38f8b050 JR |
4088 | tree, (void), |
4089 | std_build_builtin_va_list) | |
4090 | ||
4091 | /* Enumerate the va list variants. */ | |
07a5b2bc | 4092 | DEFHOOK |
38f8b050 | 4093 | (enum_va_list_p, |
673c2f63 JM |
4094 | "This target hook is used in function @code{c_common_nodes_and_builtins}\n\ |
4095 | to iterate through the target specific builtin types for va_list. The\n\ | |
4096 | variable @var{idx} is used as iterator. @var{pname} has to be a pointer\n\ | |
4097 | to a @code{const char *} and @var{ptree} a pointer to a @code{tree} typed\n\ | |
4098 | variable.\n\ | |
4099 | The arguments @var{pname} and @var{ptree} are used to store the result of\n\ | |
4100 | this macro and are set to the name of the va_list builtin type and its\n\ | |
4101 | internal type.\n\ | |
4102 | If the return value of this macro is zero, then there is no more element.\n\ | |
4103 | Otherwise the @var{IDX} should be increased for the next call of this\n\ | |
4104 | macro to iterate through all types.", | |
38f8b050 JR |
4105 | int, (int idx, const char **pname, tree *ptree), |
4106 | NULL) | |
4107 | ||
4108 | /* Get the cfun/fndecl calling abi __builtin_va_list type. */ | |
4109 | DEFHOOK | |
4110 | (fn_abi_va_list, | |
673c2f63 JM |
4111 | "This hook returns the va_list type of the calling convention specified by\n\ |
4112 | @var{fndecl}.\n\ | |
4113 | The default version of this hook returns @code{va_list_type_node}.", | |
38f8b050 JR |
4114 | tree, (tree fndecl), |
4115 | std_fn_abi_va_list) | |
4116 | ||
4117 | /* Get the __builtin_va_list type dependent on input type. */ | |
4118 | DEFHOOK | |
4119 | (canonical_va_list_type, | |
673c2f63 JM |
4120 | "This hook returns the va_list type of the calling convention specified by the\n\ |
4121 | type of @var{type}. If @var{type} is not a valid va_list type, it returns\n\ | |
4122 | @code{NULL_TREE}.", | |
38f8b050 JR |
4123 | tree, (tree type), |
4124 | std_canonical_va_list_type) | |
4125 | ||
4126 | /* ??? Documenting this hook requires a GFDL license grant. */ | |
4127 | DEFHOOK_UNDOC | |
4128 | (expand_builtin_va_start, | |
4129 | "Expand the @code{__builtin_va_start} builtin.", | |
4130 | void, (tree valist, rtx nextarg), NULL) | |
4131 | ||
4132 | /* Gimplifies a VA_ARG_EXPR. */ | |
4133 | DEFHOOK | |
4134 | (gimplify_va_arg_expr, | |
673c2f63 JM |
4135 | "This hook performs target-specific gimplification of\n\ |
4136 | @code{VA_ARG_EXPR}. The first two parameters correspond to the\n\ | |
4137 | arguments to @code{va_arg}; the latter two are as in\n\ | |
e53b6e56 | 4138 | @code{gimplify.cc:gimplify_expr}.", |
38f8b050 JR |
4139 | tree, (tree valist, tree type, gimple_seq *pre_p, gimple_seq *post_p), |
4140 | std_gimplify_va_arg_expr) | |
4141 | ||
4142 | /* Validity-checking routines for PCH files, target-specific. | |
4143 | get_pch_validity returns a pointer to the data to be stored, | |
4144 | and stores the size in its argument. pch_valid_p gets the same | |
4145 | information back and returns NULL if the PCH is valid, | |
4146 | or an error message if not. */ | |
4147 | DEFHOOK | |
4148 | (get_pch_validity, | |
673c2f63 JM |
4149 | "This hook returns a pointer to the data needed by\n\ |
4150 | @code{TARGET_PCH_VALID_P} and sets\n\ | |
4151 | @samp{*@var{sz}} to the size of the data in bytes.", | |
38f8b050 JR |
4152 | void *, (size_t *sz), |
4153 | default_get_pch_validity) | |
4154 | ||
4155 | DEFHOOK | |
4156 | (pch_valid_p, | |
673c2f63 JM |
4157 | "This hook checks whether the options used to create a PCH file are\n\ |
4158 | compatible with the current settings. It returns @code{NULL}\n\ | |
4159 | if so and a suitable error message if not. Error messages will\n\ | |
4160 | be presented to the user and must be localized using @samp{_(@var{msg})}.\n\ | |
4161 | \n\ | |
4162 | @var{data} is the data that was returned by @code{TARGET_GET_PCH_VALIDITY}\n\ | |
4163 | when the PCH file was created and @var{sz} is the size of that data in bytes.\n\ | |
4164 | It's safe to assume that the data was created by the same version of the\n\ | |
4165 | compiler, so no format checking is needed.\n\ | |
4166 | \n\ | |
4167 | The default definition of @code{default_pch_valid_p} should be\n\ | |
4168 | suitable for most targets.", | |
38f8b050 JR |
4169 | const char *, (const void *data, size_t sz), |
4170 | default_pch_valid_p) | |
4171 | ||
e32ea2d1 RS |
4172 | DEFHOOK |
4173 | (prepare_pch_save, | |
4174 | "Called before writing out a PCH file. If the target has some\n\ | |
4175 | garbage-collected data that needs to be in a particular state on PCH loads,\n\ | |
4176 | it can use this hook to enforce that state. Very few targets need\n\ | |
4177 | to do anything here.", | |
4178 | void, (void), | |
4179 | hook_void_void) | |
4180 | ||
38f8b050 JR |
4181 | /* If nonnull, this function checks whether a PCH file with the |
4182 | given set of target flags can be used. It returns NULL if so, | |
4183 | otherwise it returns an error message. */ | |
4184 | DEFHOOK | |
4185 | (check_pch_target_flags, | |
673c2f63 JM |
4186 | "If this hook is nonnull, the default implementation of\n\ |
4187 | @code{TARGET_PCH_VALID_P} will use it to check for compatible values\n\ | |
4188 | of @code{target_flags}. @var{pch_flags} specifies the value that\n\ | |
4189 | @code{target_flags} had when the PCH file was created. The return\n\ | |
4190 | value is the same as for @code{TARGET_PCH_VALID_P}.", | |
38f8b050 JR |
4191 | const char *, (int pch_flags), NULL) |
4192 | ||
4193 | /* True if the compiler should give an enum type only as many | |
4194 | bytes as it takes to represent the range of possible values of | |
4195 | that type. */ | |
4196 | DEFHOOK | |
4197 | (default_short_enums, | |
673c2f63 JM |
4198 | "This target hook should return true if the compiler should give an\n\ |
4199 | @code{enum} type only as many bytes as it takes to represent the range\n\ | |
4200 | of possible values of that type. It should return false if all\n\ | |
4201 | @code{enum} types should be allocated like @code{int}.\n\ | |
4202 | \n\ | |
4203 | The default is to return false.", | |
38f8b050 JR |
4204 | bool, (void), |
4205 | hook_bool_void_false) | |
4206 | ||
4207 | /* This target hook returns an rtx that is used to store the address | |
4208 | of the current frame into the built-in setjmp buffer. */ | |
4209 | DEFHOOK | |
4210 | (builtin_setjmp_frame_value, | |
673c2f63 JM |
4211 | "This target hook should return an rtx that is used to store\n\ |
4212 | the address of the current frame into the built in @code{setjmp} buffer.\n\ | |
4213 | The default value, @code{virtual_stack_vars_rtx}, is correct for most\n\ | |
4214 | machines. One reason you may need to define this target hook is if\n\ | |
4215 | @code{hard_frame_pointer_rtx} is the appropriate value on your machine.", | |
38f8b050 JR |
4216 | rtx, (void), |
4217 | default_builtin_setjmp_frame_value) | |
4218 | ||
7ca35180 RH |
4219 | /* This target hook should manipulate the outputs, inputs, constraints, |
4220 | and clobbers the port wishes for pre-processing the asm. */ | |
4221 | DEFHOOK | |
4222 | (md_asm_adjust, | |
4223 | "This target hook may add @dfn{clobbers} to @var{clobbers} and\n\ | |
4224 | @var{clobbered_regs} for any hard regs the port wishes to automatically\n\ | |
4225 | clobber for an asm. The @var{outputs} and @var{inputs} may be inspected\n\ | |
8d76ff99 TS |
4226 | to avoid clobbering a register that is already used by the asm. @var{loc}\n\ |
4227 | is the source location of the asm.\n\ | |
7ca35180 | 4228 | \n\ |
e52ef6e6 IL |
4229 | It may modify the @var{outputs}, @var{inputs}, @var{input_modes}, and\n\ |
4230 | @var{constraints} as necessary for other pre-processing. In this case the\n\ | |
4231 | return value is a sequence of insns to emit after the asm. Note that\n\ | |
4232 | changes to @var{inputs} must be accompanied by the corresponding changes\n\ | |
4233 | to @var{input_modes}.", | |
7ca35180 | 4234 | rtx_insn *, |
e52ef6e6 IL |
4235 | (vec<rtx>& outputs, vec<rtx>& inputs, vec<machine_mode>& input_modes, |
4236 | vec<const char *>& constraints, vec<rtx>& clobbers, | |
8d76ff99 | 4237 | HARD_REG_SET& clobbered_regs, location_t loc), |
7ca35180 | 4238 | NULL) |
38f8b050 JR |
4239 | |
4240 | /* This target hook allows the backend to specify a calling convention | |
4241 | in the debug information. This function actually returns an | |
4242 | enum dwarf_calling_convention, but because of forward declarations | |
4243 | and not wanting to include dwarf2.h everywhere target.h is included | |
4244 | the function is being declared as an int. */ | |
4245 | DEFHOOK | |
4246 | (dwarf_calling_convention, | |
673c2f63 JM |
4247 | "Define this to enable the dwarf attribute @code{DW_AT_calling_convention} to\n\ |
4248 | be emitted for each function. Instead of an integer return the enum\n\ | |
4249 | value for the @code{DW_CC_} tag.", | |
38f8b050 JR |
4250 | int, (const_tree function), |
4251 | hook_int_const_tree_0) | |
4252 | ||
4253 | /* This target hook allows the backend to emit frame-related insns that | |
4254 | contain UNSPECs or UNSPEC_VOLATILEs. The call frame debugging info | |
4255 | engine will invoke it on insns of the form | |
4256 | (set (reg) (unspec [...] UNSPEC_INDEX)) | |
4257 | and | |
4258 | (set (reg) (unspec_volatile [...] UNSPECV_INDEX)) | |
4259 | to let the backend emit the call frame instructions. */ | |
4260 | DEFHOOK | |
4261 | (dwarf_handle_frame_unspec, | |
673c2f63 JM |
4262 | "This target hook allows the backend to emit frame-related insns that\n\ |
4263 | contain UNSPECs or UNSPEC_VOLATILEs. The DWARF 2 call frame debugging\n\ | |
4264 | info engine will invoke it on insns of the form\n\ | |
4265 | @smallexample\n\ | |
4266 | (set (reg) (unspec [@dots{}] UNSPEC_INDEX))\n\ | |
4267 | @end smallexample\n\ | |
4268 | and\n\ | |
4269 | @smallexample\n\ | |
4270 | (set (reg) (unspec_volatile [@dots{}] UNSPECV_INDEX)).\n\ | |
4271 | @end smallexample\n\ | |
4272 | to let the backend emit the call frame instructions. @var{label} is\n\ | |
4273 | the CFI label attached to the insn, @var{pattern} is the pattern of\n\ | |
4274 | the insn and @var{index} is @code{UNSPEC_INDEX} or @code{UNSPECV_INDEX}.", | |
38f8b050 JR |
4275 | void, (const char *label, rtx pattern, int index), NULL) |
4276 | ||
74c74aa0 RS |
4277 | DEFHOOK |
4278 | (dwarf_poly_indeterminate_value, | |
4279 | "Express the value of @code{poly_int} indeterminate @var{i} as a DWARF\n\ | |
4280 | expression, with @var{i} counting from 1. Return the number of a DWARF\n\ | |
4281 | register @var{R} and set @samp{*@var{factor}} and @samp{*@var{offset}} such\n\ | |
4282 | that the value of the indeterminate is:\n\ | |
4283 | @smallexample\n\ | |
4284 | value_of(@var{R}) / @var{factor} - @var{offset}\n\ | |
4285 | @end smallexample\n\ | |
4286 | \n\ | |
4287 | A target only needs to define this hook if it sets\n\ | |
4288 | @samp{NUM_POLY_INT_COEFFS} to a value greater than 1.", | |
4289 | unsigned int, (unsigned int i, unsigned int *factor, int *offset), | |
4290 | default_dwarf_poly_indeterminate_value) | |
4291 | ||
38f8b050 JR |
4292 | /* ??? Documenting this hook requires a GFDL license grant. */ |
4293 | DEFHOOK_UNDOC | |
4294 | (stdarg_optimize_hook, | |
4295 | "Perform architecture specific checking of statements gimplified\ | |
4296 | from @code{VA_ARG_EXPR}. @var{stmt} is the statement. Returns true if\ | |
4297 | the statement doesn't need to be checked for @code{va_list} references.", | |
355fe088 | 4298 | bool, (struct stdarg_info *ai, const gimple *stmt), NULL) |
38f8b050 JR |
4299 | |
4300 | /* This target hook allows the operating system to override the DECL | |
4301 | that represents the external variable that contains the stack | |
4302 | protection guard variable. The type of this DECL is ptr_type_node. */ | |
4303 | DEFHOOK | |
4304 | (stack_protect_guard, | |
673c2f63 JM |
4305 | "This hook returns a @code{DECL} node for the external variable to use\n\ |
4306 | for the stack protection guard. This variable is initialized by the\n\ | |
4307 | runtime to some random value and is used to initialize the guard value\n\ | |
4308 | that is placed at the top of the local stack frame. The type of this\n\ | |
4309 | variable must be @code{ptr_type_node}.\n\ | |
4310 | \n\ | |
4311 | The default version of this hook creates a variable called\n\ | |
4312 | @samp{__stack_chk_guard}, which is normally defined in @file{libgcc2.c}.", | |
38f8b050 JR |
4313 | tree, (void), |
4314 | default_stack_protect_guard) | |
4315 | ||
4316 | /* This target hook allows the operating system to override the CALL_EXPR | |
4317 | that is invoked when a check vs the guard variable fails. */ | |
4318 | DEFHOOK | |
4319 | (stack_protect_fail, | |
673c2f63 JM |
4320 | "This hook returns a @code{CALL_EXPR} that alerts the runtime that the\n\ |
4321 | stack protect guard variable has been modified. This expression should\n\ | |
4322 | involve a call to a @code{noreturn} function.\n\ | |
4323 | \n\ | |
4324 | The default version of this hook invokes a function called\n\ | |
4325 | @samp{__stack_chk_fail}, taking no arguments. This function is\n\ | |
4326 | normally defined in @file{libgcc2.c}.", | |
38f8b050 JR |
4327 | tree, (void), |
4328 | default_external_stack_protect_fail) | |
4329 | ||
87a5dc2d JW |
4330 | /* This target hook allows the operating system to disable the default stack |
4331 | protector runtime support. */ | |
4332 | DEFHOOK | |
4333 | (stack_protect_runtime_enabled_p, | |
4d3907c2 ML |
4334 | "Returns true if the target wants GCC's default stack protect runtime support,\n\ |
4335 | otherwise return false. The default implementation always returns true.", | |
87a5dc2d JW |
4336 | bool, (void), |
4337 | hook_bool_void_true) | |
4338 | ||
425fc685 RE |
4339 | DEFHOOK |
4340 | (have_speculation_safe_value, | |
4341 | "This hook is used to determine the level of target support for\n\ | |
4342 | @code{__builtin_speculation_safe_value}. If called with an argument\n\ | |
4343 | of false, it returns true if the target has been modified to support\n\ | |
4344 | this builtin. If called with an argument of true, it returns true\n\ | |
4345 | if the target requires active mitigation execution might be speculative.\n\ | |
4346 | \n\ | |
4347 | The default implementation returns false if the target does not define\n\ | |
4348 | a pattern named @code{speculation_barrier}. Else it returns true\n\ | |
4349 | for the first case and whether the pattern is enabled for the current\n\ | |
f3debef3 RE |
4350 | compilation for the second case.\n\ |
4351 | \n\ | |
4352 | For targets that have no processors that can execute instructions\n\ | |
4353 | speculatively an alternative implemenation of this hook is available:\n\ | |
4354 | simply redefine this hook to @code{speculation_safe_value_not_needed}\n\ | |
4355 | along with your other target hooks.", | |
425fc685 RE |
4356 | bool, (bool active), default_have_speculation_safe_value) |
4357 | ||
4358 | DEFHOOK | |
4359 | (speculation_safe_value, | |
4360 | "This target hook can be used to generate a target-specific code\n\ | |
4361 | sequence that implements the @code{__builtin_speculation_safe_value}\n\ | |
4362 | built-in function. The function must always return @var{val} in\n\ | |
4363 | @var{result} in mode @var{mode} when the cpu is not executing\n\ | |
4364 | speculatively, but must never return that when speculating until it\n\ | |
4365 | is known that the speculation will not be unwound. The hook supports\n\ | |
4366 | two primary mechanisms for implementing the requirements. The first\n\ | |
4367 | is to emit a speculation barrier which forces the processor to wait\n\ | |
4368 | until all prior speculative operations have been resolved; the second\n\ | |
4369 | is to use a target-specific mechanism that can track the speculation\n\ | |
4370 | state and to return @var{failval} if it can determine that\n\ | |
4371 | speculation must be unwound at a later time.\n\ | |
4372 | \n\ | |
4373 | The default implementation simply copies @var{val} to @var{result} and\n\ | |
4374 | emits a @code{speculation_barrier} instruction if that is defined.", | |
4375 | rtx, (machine_mode mode, rtx result, rtx val, rtx failval), | |
4376 | default_speculation_safe_value) | |
4377 | ||
74b5fcf7 KL |
4378 | DEFHOOK |
4379 | (predict_doloop_p, | |
4380 | "Return true if we can predict it is possible to use a low-overhead loop\n\ | |
4381 | for a particular loop. The parameter @var{loop} is a pointer to the loop.\n\ | |
4382 | This target hook is required only when the target supports low-overhead\n\ | |
4383 | loops, and will help ivopts to make some decisions.\n\ | |
4384 | The default version of this hook returns false.", | |
99b1c316 | 4385 | bool, (class loop *loop), |
74b5fcf7 | 4386 | default_predict_doloop_p) |
425fc685 | 4387 | |
603a4ad4 KL |
4388 | DEFHOOKPOD |
4389 | (have_count_reg_decr_p, | |
4390 | "Return true if the target supports hardware count register for decrement\n\ | |
4391 | and branch.\n\ | |
4392 | The default value is false.", | |
4393 | bool, false) | |
4394 | ||
4395 | DEFHOOKPOD | |
4396 | (doloop_cost_for_generic, | |
4397 | "One IV candidate dedicated for doloop is introduced in IVOPTs, we can\n\ | |
4398 | calculate the computation cost of adopting it to any generic IV use by\n\ | |
4399 | function get_computation_cost as before. But for targets which have\n\ | |
4400 | hardware count register support for decrement and branch, it may have to\n\ | |
4401 | move IV value from hardware count register to general purpose register\n\ | |
4402 | while doloop IV candidate is used for generic IV uses. It probably takes\n\ | |
4403 | expensive penalty. This hook allows target owners to define the cost for\n\ | |
4404 | this especially for generic IV uses.\n\ | |
4405 | The default value is zero.", | |
4406 | int64_t, 0) | |
4407 | ||
4408 | DEFHOOKPOD | |
4409 | (doloop_cost_for_address, | |
4410 | "One IV candidate dedicated for doloop is introduced in IVOPTs, we can\n\ | |
4411 | calculate the computation cost of adopting it to any address IV use by\n\ | |
4412 | function get_computation_cost as before. But for targets which have\n\ | |
4413 | hardware count register support for decrement and branch, it may have to\n\ | |
4414 | move IV value from hardware count register to general purpose register\n\ | |
4415 | while doloop IV candidate is used for address IV uses. It probably takes\n\ | |
4416 | expensive penalty. This hook allows target owners to define the cost for\n\ | |
4417 | this escpecially for address IV uses.\n\ | |
4418 | The default value is zero.", | |
4419 | int64_t, 0) | |
4420 | ||
1d0216c8 RS |
4421 | DEFHOOK |
4422 | (can_use_doloop_p, | |
4423 | "Return true if it is possible to use low-overhead loops (@code{doloop_end}\n\ | |
4424 | and @code{doloop_begin}) for a particular loop. @var{iterations} gives the\n\ | |
4425 | exact number of iterations, or 0 if not known. @var{iterations_max} gives\n\ | |
4426 | the maximum number of iterations, or 0 if not known. @var{loop_depth} is\n\ | |
4427 | the nesting depth of the loop, with 1 for innermost loops, 2 for loops that\n\ | |
4428 | contain innermost loops, and so on. @var{entered_at_top} is true if the\n\ | |
4429 | loop is only entered from the top.\n\ | |
4430 | \n\ | |
4431 | This hook is only used if @code{doloop_end} is available. The default\n\ | |
4432 | implementation returns true. You can use @code{can_use_doloop_if_innermost}\n\ | |
4433 | if the loop must be the innermost, and if there are no other restrictions.", | |
807e902e | 4434 | bool, (const widest_int &iterations, const widest_int &iterations_max, |
1d0216c8 | 4435 | unsigned int loop_depth, bool entered_at_top), |
807e902e | 4436 | hook_bool_wint_wint_uint_bool_true) |
1d0216c8 | 4437 | |
38f8b050 JR |
4438 | /* Returns NULL if target supports the insn within a doloop block, |
4439 | otherwise it returns an error message. */ | |
4440 | DEFHOOK | |
4441 | (invalid_within_doloop, | |
673c2f63 JM |
4442 | "\n\ |
4443 | Take an instruction in @var{insn} and return NULL if it is valid within a\n\ | |
4444 | low-overhead loop, otherwise return a string explaining why doloop\n\ | |
4445 | could not be applied.\n\ | |
4446 | \n\ | |
4447 | Many targets use special registers for low-overhead looping. For any\n\ | |
4448 | instruction that clobbers these this function should return a string indicating\n\ | |
4449 | the reason why the doloop could not be applied.\n\ | |
4450 | By default, the RTL loop optimizer does not use a present doloop pattern for\n\ | |
4451 | loops containing function calls or branch on table instructions.", | |
ac44248e | 4452 | const char *, (const rtx_insn *insn), |
38f8b050 JR |
4453 | default_invalid_within_doloop) |
4454 | ||
aafa38b5 JG |
4455 | /* Returns the machine mode which the target prefers for doloop IV. */ |
4456 | DEFHOOK | |
4457 | (preferred_doloop_mode, | |
4458 | "This hook takes a @var{mode} for a doloop IV, where @code{mode} is the\n\ | |
4459 | original mode for the operation. If the target prefers an alternate\n\ | |
4460 | @code{mode} for the operation, then this hook should return that mode;\n\ | |
4461 | otherwise the original @code{mode} should be returned. For example, on a\n\ | |
4462 | 64-bit target, @code{DImode} might be preferred over @code{SImode}. Both the\n\ | |
4463 | original and the returned modes should be @code{MODE_INT}.", | |
4464 | machine_mode, | |
4465 | (machine_mode mode), | |
4466 | default_preferred_doloop_mode) | |
4467 | ||
78e4f1ad UB |
4468 | /* Returns true for a legitimate combined insn. */ |
4469 | DEFHOOK | |
4470 | (legitimate_combined_insn, | |
4d3907c2 ML |
4471 | "Take an instruction in @var{insn} and return @code{false} if the instruction\n\ |
4472 | is not appropriate as a combination of two or more instructions. The\n\ | |
4473 | default is to accept all instructions.", | |
ac44248e DM |
4474 | bool, (rtx_insn *insn), |
4475 | hook_bool_rtx_insn_true) | |
78e4f1ad | 4476 | |
38f8b050 JR |
4477 | DEFHOOK |
4478 | (valid_dllimport_attribute_p, | |
4d3907c2 ML |
4479 | "@var{decl} is a variable or function with @code{__attribute__((dllimport))}\n\ |
4480 | specified. Use this hook if the target needs to add extra validation\n\ | |
4481 | checks to @code{handle_dll_attribute}.", | |
38f8b050 JR |
4482 | bool, (const_tree decl), |
4483 | hook_bool_const_tree_true) | |
4484 | ||
4485 | /* If non-zero, align constant anchors in CSE to a multiple of this | |
4486 | value. */ | |
4487 | DEFHOOKPOD | |
4488 | (const_anchor, | |
673c2f63 JM |
4489 | "On some architectures it can take multiple instructions to synthesize\n\ |
4490 | a constant. If there is another constant already in a register that\n\ | |
4491 | is close enough in value then it is preferable that the new constant\n\ | |
4492 | is computed from this register using immediate addition or\n\ | |
4493 | subtraction. We accomplish this through CSE. Besides the value of\n\ | |
4494 | the constant we also add a lower and an upper constant anchor to the\n\ | |
4495 | available expressions. These are then queried when encountering new\n\ | |
4496 | constants. The anchors are computed by rounding the constant up and\n\ | |
4497 | down to a multiple of the value of @code{TARGET_CONST_ANCHOR}.\n\ | |
4498 | @code{TARGET_CONST_ANCHOR} should be the maximum positive value\n\ | |
4499 | accepted by immediate-add plus one. We currently assume that the\n\ | |
4500 | value of @code{TARGET_CONST_ANCHOR} is a power of 2. For example, on\n\ | |
4501 | MIPS, where add-immediate takes a 16-bit signed value,\n\ | |
4502 | @code{TARGET_CONST_ANCHOR} is set to @samp{0x8000}. The default value\n\ | |
4503 | is zero, which disables this optimization.", | |
38f8b050 JR |
4504 | unsigned HOST_WIDE_INT, 0) |
4505 | ||
5dcfdccd KY |
4506 | /* Defines, which target-dependent bits (upper 16) are used by port */ |
4507 | DEFHOOK | |
4508 | (memmodel_check, | |
673c2f63 JM |
4509 | "Validate target specific memory model mask bits. When NULL no target specific\n\ |
4510 | memory model bits are allowed.", | |
5dcfdccd KY |
4511 | unsigned HOST_WIDE_INT, (unsigned HOST_WIDE_INT val), NULL) |
4512 | ||
dfe06d3e JJ |
4513 | /* Defines an offset bitwise ored into shifted address to get corresponding |
4514 | Address Sanitizer shadow address, or -1 if Address Sanitizer is not | |
4515 | supported by the target. */ | |
4516 | DEFHOOK | |
4517 | (asan_shadow_offset, | |
4518 | "Return the offset bitwise ored into shifted address to get corresponding\n\ | |
4519 | Address Sanitizer shadow memory address. NULL if Address Sanitizer is not\n\ | |
dcf0dde4 JW |
4520 | supported by the target. May return 0 if Address Sanitizer is not supported\n\ |
4521 | by a subtarget.", | |
dfe06d3e JJ |
4522 | unsigned HOST_WIDE_INT, (void), |
4523 | NULL) | |
4524 | ||
38f8b050 JR |
4525 | /* Functions relating to calls - argument passing, returns, etc. */ |
4526 | /* Members of struct call have no special macro prefix. */ | |
4527 | HOOK_VECTOR (TARGET_CALLS, calls) | |
4528 | ||
4529 | DEFHOOK | |
4530 | (promote_function_mode, | |
673c2f63 JM |
4531 | "Like @code{PROMOTE_MODE}, but it is applied to outgoing function arguments or\n\ |
4532 | function return values. The target hook should return the new mode\n\ | |
4533 | and possibly change @code{*@var{punsignedp}} if the promotion should\n\ | |
4534 | change signedness. This function is called only for scalar @emph{or\n\ | |
4535 | pointer} types.\n\ | |
4536 | \n\ | |
4537 | @var{for_return} allows to distinguish the promotion of arguments and\n\ | |
4538 | return values. If it is @code{1}, a return value is being promoted and\n\ | |
4539 | @code{TARGET_FUNCTION_VALUE} must perform the same promotions done here.\n\ | |
4540 | If it is @code{2}, the returned mode should be that of the register in\n\ | |
4541 | which an incoming parameter is copied, or the outgoing result is computed;\n\ | |
4542 | then the hook should return the same mode as @code{promote_mode}, though\n\ | |
4543 | the signedness may be different.\n\ | |
4544 | \n\ | |
4545 | @var{type} can be NULL when promoting function arguments of libcalls.\n\ | |
4546 | \n\ | |
4547 | The default is to not promote arguments and return values. You can\n\ | |
4548 | also define the hook to @code{default_promote_function_mode_always_promote}\n\ | |
4549 | if you would like to apply the same rules given by @code{PROMOTE_MODE}.", | |
ef4bddc2 | 4550 | machine_mode, (const_tree type, machine_mode mode, int *punsignedp, |
38f8b050 JR |
4551 | const_tree funtype, int for_return), |
4552 | default_promote_function_mode) | |
4553 | ||
4554 | DEFHOOK | |
4555 | (promote_prototypes, | |
673c2f63 JM |
4556 | "This target hook returns @code{true} if an argument declared in a\n\ |
4557 | prototype as an integral type smaller than @code{int} should actually be\n\ | |
4558 | passed as an @code{int}. In addition to avoiding errors in certain\n\ | |
4559 | cases of mismatch, it also makes for better code on certain machines.\n\ | |
4560 | The default is to not promote prototypes.", | |
38f8b050 JR |
4561 | bool, (const_tree fntype), |
4562 | hook_bool_const_tree_false) | |
4563 | ||
4564 | DEFHOOK | |
4565 | (struct_value_rtx, | |
673c2f63 JM |
4566 | "This target hook should return the location of the structure value\n\ |
4567 | address (normally a @code{mem} or @code{reg}), or 0 if the address is\n\ | |
4568 | passed as an ``invisible'' first argument. Note that @var{fndecl} may\n\ | |
4569 | be @code{NULL}, for libcalls. You do not need to define this target\n\ | |
4570 | hook if the address is always passed as an ``invisible'' first\n\ | |
4571 | argument.\n\ | |
4572 | \n\ | |
4573 | On some architectures the place where the structure value address\n\ | |
4574 | is found by the called function is not the same place that the\n\ | |
4575 | caller put it. This can be due to register windows, or it could\n\ | |
4576 | be because the function prologue moves it to a different place.\n\ | |
4577 | @var{incoming} is @code{1} or @code{2} when the location is needed in\n\ | |
4578 | the context of the called function, and @code{0} in the context of\n\ | |
4579 | the caller.\n\ | |
4580 | \n\ | |
4581 | If @var{incoming} is nonzero and the address is to be found on the\n\ | |
4582 | stack, return a @code{mem} which refers to the frame pointer. If\n\ | |
4583 | @var{incoming} is @code{2}, the result is being used to fetch the\n\ | |
4584 | structure value address at the beginning of a function. If you need\n\ | |
4585 | to emit adjusting code, you should do it at this point.", | |
38f8b050 JR |
4586 | rtx, (tree fndecl, int incoming), |
4587 | hook_rtx_tree_int_null) | |
e0d14c39 BS |
4588 | |
4589 | DEFHOOKPOD | |
4590 | (omit_struct_return_reg, | |
4591 | "Normally, when a function returns a structure by memory, the address\n\ | |
4592 | is passed as an invisible pointer argument, but the compiler also\n\ | |
4593 | arranges to return the address from the function like it would a normal\n\ | |
9c582551 | 4594 | pointer return value. Define this to true if that behavior is\n\ |
e0d14c39 BS |
4595 | undesirable on your target.", |
4596 | bool, false) | |
4597 | ||
38f8b050 JR |
4598 | DEFHOOK |
4599 | (return_in_memory, | |
673c2f63 JM |
4600 | "This target hook should return a nonzero value to say to return the\n\ |
4601 | function value in memory, just as large structures are always returned.\n\ | |
4602 | Here @var{type} will be the data type of the value, and @var{fntype}\n\ | |
4603 | will be the type of the function doing the returning, or @code{NULL} for\n\ | |
4604 | libcalls.\n\ | |
4605 | \n\ | |
4606 | Note that values of mode @code{BLKmode} must be explicitly handled\n\ | |
4607 | by this function. Also, the option @option{-fpcc-struct-return}\n\ | |
4608 | takes effect regardless of this macro. On most systems, it is\n\ | |
4609 | possible to leave the hook undefined; this causes a default\n\ | |
4610 | definition to be used, whose value is the constant 1 for @code{BLKmode}\n\ | |
4611 | values, and 0 otherwise.\n\ | |
4612 | \n\ | |
4613 | Do not use this hook to indicate that structures and unions should always\n\ | |
4614 | be returned in memory. You should instead use @code{DEFAULT_PCC_STRUCT_RETURN}\n\ | |
4615 | to indicate this.", | |
38f8b050 JR |
4616 | bool, (const_tree type, const_tree fntype), |
4617 | default_return_in_memory) | |
4618 | ||
4619 | DEFHOOK | |
4620 | (return_in_msb, | |
673c2f63 JM |
4621 | "This hook should return true if values of type @var{type} are returned\n\ |
4622 | at the most significant end of a register (in other words, if they are\n\ | |
4623 | padded at the least significant end). You can assume that @var{type}\n\ | |
4624 | is returned in a register; the caller is required to check this.\n\ | |
4625 | \n\ | |
4626 | Note that the register provided by @code{TARGET_FUNCTION_VALUE} must\n\ | |
4627 | be able to hold the complete return value. For example, if a 1-, 2-\n\ | |
4628 | or 3-byte structure is returned at the most significant end of a\n\ | |
4629 | 4-byte register, @code{TARGET_FUNCTION_VALUE} should provide an\n\ | |
4630 | @code{SImode} rtx.", | |
38f8b050 JR |
4631 | bool, (const_tree type), |
4632 | hook_bool_const_tree_false) | |
4633 | ||
4634 | /* Return true if a parameter must be passed by reference. TYPE may | |
4635 | be null if this is a libcall. CA may be null if this query is | |
4636 | from __builtin_va_arg. */ | |
ec9f85e5 | 4637 | DEFHOOK |
38f8b050 | 4638 | (pass_by_reference, |
52090e4d | 4639 | "This target hook should return @code{true} if argument @var{arg} at the\n\ |
673c2f63 JM |
4640 | position indicated by @var{cum} should be passed by reference. This\n\ |
4641 | predicate is queried after target independent reasons for being\n\ | |
52090e4d | 4642 | passed by reference, such as @code{TREE_ADDRESSABLE (@var{arg}.type)}.\n\ |
673c2f63 JM |
4643 | \n\ |
4644 | If the hook returns true, a copy of that argument is made in memory and a\n\ | |
4645 | pointer to the argument is passed instead of the argument itself.\n\ | |
4646 | The pointer is passed in whatever way is appropriate for passing a pointer\n\ | |
4647 | to that type.", | |
38f8b050 | 4648 | bool, |
52090e4d RS |
4649 | (cumulative_args_t cum, const function_arg_info &arg), |
4650 | hook_bool_CUMULATIVE_ARGS_arg_info_false) | |
38f8b050 JR |
4651 | |
4652 | DEFHOOK | |
4653 | (expand_builtin_saveregs, | |
673c2f63 JM |
4654 | "If defined, this hook produces the machine-specific code for a call to\n\ |
4655 | @code{__builtin_saveregs}. This code will be moved to the very\n\ | |
4656 | beginning of the function, before any parameter access are made. The\n\ | |
4657 | return value of this function should be an RTX that contains the value\n\ | |
4658 | to use as the return of @code{__builtin_saveregs}.", | |
38f8b050 JR |
4659 | rtx, (void), |
4660 | default_expand_builtin_saveregs) | |
4661 | ||
4662 | /* Returns pretend_argument_size. */ | |
4663 | DEFHOOK | |
4664 | (setup_incoming_varargs, | |
673c2f63 JM |
4665 | "This target hook offers an alternative to using\n\ |
4666 | @code{__builtin_saveregs} and defining the hook\n\ | |
4667 | @code{TARGET_EXPAND_BUILTIN_SAVEREGS}. Use it to store the anonymous\n\ | |
4668 | register arguments into the stack so that all the arguments appear to\n\ | |
4669 | have been passed consecutively on the stack. Once this is done, you can\n\ | |
4670 | use the standard implementation of varargs that works for machines that\n\ | |
4671 | pass all their arguments on the stack.\n\ | |
4672 | \n\ | |
4673 | The argument @var{args_so_far} points to the @code{CUMULATIVE_ARGS} data\n\ | |
4674 | structure, containing the values that are obtained after processing the\n\ | |
e7056ca4 RS |
4675 | named arguments. The argument @var{arg} describes the last of these named\n\ |
4676 | arguments.\n\ | |
673c2f63 JM |
4677 | \n\ |
4678 | The target hook should do two things: first, push onto the stack all the\n\ | |
4679 | argument registers @emph{not} used for the named arguments, and second,\n\ | |
4680 | store the size of the data thus pushed into the @code{int}-valued\n\ | |
4681 | variable pointed to by @var{pretend_args_size}. The value that you\n\ | |
4682 | store here will serve as additional offset for setting up the stack\n\ | |
4683 | frame.\n\ | |
4684 | \n\ | |
4685 | Because you must generate code to push the anonymous arguments at\n\ | |
4686 | compile time without knowing their data types,\n\ | |
4687 | @code{TARGET_SETUP_INCOMING_VARARGS} is only useful on machines that\n\ | |
4688 | have just a single category of argument register and use it uniformly\n\ | |
4689 | for all data types.\n\ | |
4690 | \n\ | |
4691 | If the argument @var{second_time} is nonzero, it means that the\n\ | |
4692 | arguments of the function are being analyzed for the second time. This\n\ | |
4693 | happens for an inline function, which is not actually compiled until the\n\ | |
4694 | end of the source file. The hook @code{TARGET_SETUP_INCOMING_VARARGS} should\n\ | |
4695 | not generate any instructions in this case.", | |
e7056ca4 | 4696 | void, (cumulative_args_t args_so_far, const function_arg_info &arg, |
38f8b050 JR |
4697 | int *pretend_args_size, int second_time), |
4698 | default_setup_incoming_varargs) | |
4699 | ||
2f21e1ba BS |
4700 | DEFHOOK |
4701 | (call_args, | |
4702 | "While generating RTL for a function call, this target hook is invoked once\n\ | |
4703 | for each argument passed to the function, either a register returned by\n\ | |
4704 | @code{TARGET_FUNCTION_ARG} or a memory location. It is called just\n\ | |
4705 | before the point where argument registers are stored. The type of the\n\ | |
4706 | function to be called is also passed as the second argument; it is\n\ | |
4707 | @code{NULL_TREE} for libcalls. The @code{TARGET_END_CALL_ARGS} hook is\n\ | |
4708 | invoked just after the code to copy the return reg has been emitted.\n\ | |
4709 | This functionality can be used to perform special setup of call argument\n\ | |
4710 | registers if a target needs it.\n\ | |
4711 | For functions without arguments, the hook is called once with @code{pc_rtx}\n\ | |
4712 | passed instead of an argument register.\n\ | |
4713 | Most ports do not need to implement anything for this hook.", | |
4714 | void, (rtx, tree), | |
4715 | hook_void_rtx_tree) | |
4716 | ||
4717 | DEFHOOK | |
4718 | (end_call_args, | |
4719 | "This target hook is invoked while generating RTL for a function call,\n\ | |
4720 | just after the point where the return reg is copied into a pseudo. It\n\ | |
4721 | signals that all the call argument and return registers for the just\n\ | |
4722 | emitted call are now no longer in use.\n\ | |
4723 | Most ports do not need to implement anything for this hook.", | |
4724 | void, (void), | |
4725 | hook_void_void) | |
4726 | ||
967b4653 L |
4727 | DEFHOOK |
4728 | (push_argument, | |
4729 | "This target hook returns @code{true} if push instructions will be\n\ | |
4730 | used to pass outgoing arguments. When the push instruction usage is\n\ | |
4731 | optional, @var{npush} is nonzero to indicate the number of bytes to\n\ | |
4732 | push. Otherwise, @var{npush} is zero. If the target machine does not\n\ | |
4733 | have a push instruction or push instruction should be avoided,\n\ | |
4734 | @code{false} should be returned. That directs GCC to use an alternate\n\ | |
4735 | strategy: to allocate the entire argument block and then store the\n\ | |
4736 | arguments into it. If this target hook may return @code{true},\n\ | |
4737 | @code{PUSH_ROUNDING} must be defined.", | |
4738 | bool, (unsigned int npush), | |
4739 | default_push_argument) | |
4740 | ||
38f8b050 JR |
4741 | DEFHOOK |
4742 | (strict_argument_naming, | |
673c2f63 JM |
4743 | "Define this hook to return @code{true} if the location where a function\n\ |
4744 | argument is passed depends on whether or not it is a named argument.\n\ | |
4745 | \n\ | |
4746 | This hook controls how the @var{named} argument to @code{TARGET_FUNCTION_ARG}\n\ | |
4747 | is set for varargs and stdarg functions. If this hook returns\n\ | |
4748 | @code{true}, the @var{named} argument is always true for named\n\ | |
4749 | arguments, and false for unnamed arguments. If it returns @code{false},\n\ | |
4750 | but @code{TARGET_PRETEND_OUTGOING_VARARGS_NAMED} returns @code{true},\n\ | |
4751 | then all arguments are treated as named. Otherwise, all named arguments\n\ | |
4752 | except the last are treated as named.\n\ | |
4753 | \n\ | |
4754 | You need not define this hook if it always returns @code{false}.", | |
d5cc9181 | 4755 | bool, (cumulative_args_t ca), |
38f8b050 JR |
4756 | hook_bool_CUMULATIVE_ARGS_false) |
4757 | ||
4758 | /* Returns true if we should use | |
4759 | targetm.calls.setup_incoming_varargs() and/or | |
4760 | targetm.calls.strict_argument_naming(). */ | |
4761 | DEFHOOK | |
4762 | (pretend_outgoing_varargs_named, | |
673c2f63 JM |
4763 | "If you need to conditionally change ABIs so that one works with\n\ |
4764 | @code{TARGET_SETUP_INCOMING_VARARGS}, but the other works like neither\n\ | |
4765 | @code{TARGET_SETUP_INCOMING_VARARGS} nor @code{TARGET_STRICT_ARGUMENT_NAMING} was\n\ | |
4766 | defined, then define this hook to return @code{true} if\n\ | |
4767 | @code{TARGET_SETUP_INCOMING_VARARGS} is used, @code{false} otherwise.\n\ | |
4768 | Otherwise, you should not define this hook.", | |
d5cc9181 | 4769 | bool, (cumulative_args_t ca), |
38f8b050 JR |
4770 | default_pretend_outgoing_varargs_named) |
4771 | ||
4772 | /* Given a complex type T, return true if a parameter of type T | |
4773 | should be passed as two scalars. */ | |
4774 | DEFHOOK | |
4775 | (split_complex_arg, | |
673c2f63 JM |
4776 | "This hook should return true if parameter of type @var{type} are passed\n\ |
4777 | as two scalar parameters. By default, GCC will attempt to pack complex\n\ | |
4778 | arguments into the target's word size. Some ABIs require complex arguments\n\ | |
4779 | to be split and treated as their individual components. For example, on\n\ | |
4780 | AIX64, complex floats should be passed in a pair of floating point\n\ | |
4781 | registers, even though a complex float would fit in one 64-bit floating\n\ | |
4782 | point register.\n\ | |
4783 | \n\ | |
4784 | The default value of this hook is @code{NULL}, which is treated as always\n\ | |
4785 | false.", | |
38f8b050 JR |
4786 | bool, (const_tree type), NULL) |
4787 | ||
4788 | /* Return true if type T, mode MODE, may not be passed in registers, | |
4789 | but must be passed on the stack. */ | |
4790 | /* ??? This predicate should be applied strictly after pass-by-reference. | |
4791 | Need audit to verify that this is the case. */ | |
4792 | DEFHOOK | |
4793 | (must_pass_in_stack, | |
0ffef200 | 4794 | "This target hook should return @code{true} if we should not pass @var{arg}\n\ |
673c2f63 JM |
4795 | solely in registers. The file @file{expr.h} defines a\n\ |
4796 | definition that is usually appropriate, refer to @file{expr.h} for additional\n\ | |
4797 | documentation.", | |
0ffef200 | 4798 | bool, (const function_arg_info &arg), |
38f8b050 JR |
4799 | must_pass_in_stack_var_size_or_pad) |
4800 | ||
4801 | /* Return true if type TYPE, mode MODE, which is passed by reference, | |
4802 | should have the object copy generated by the callee rather than | |
4803 | the caller. It is never called for TYPE requiring constructors. */ | |
4804 | DEFHOOK | |
4805 | (callee_copies, | |
673c2f63 JM |
4806 | "The function argument described by the parameters to this hook is\n\ |
4807 | known to be passed by reference. The hook should return true if the\n\ | |
4808 | function argument should be copied by the callee instead of copied\n\ | |
4809 | by the caller.\n\ | |
4810 | \n\ | |
4811 | For any argument for which the hook returns true, if it can be\n\ | |
4812 | determined that the argument is not modified, then a copy need\n\ | |
4813 | not be generated.\n\ | |
4814 | \n\ | |
4815 | The default version of this hook always returns false.", | |
38f8b050 | 4816 | bool, |
7256c719 RS |
4817 | (cumulative_args_t cum, const function_arg_info &arg), |
4818 | hook_bool_CUMULATIVE_ARGS_arg_info_false) | |
38f8b050 JR |
4819 | |
4820 | /* Return zero for arguments passed entirely on the stack or entirely | |
4821 | in registers. If passed in both, return the number of bytes passed | |
4822 | in registers; the balance is therefore passed on the stack. */ | |
4823 | DEFHOOK | |
4824 | (arg_partial_bytes, | |
673c2f63 JM |
4825 | "This target hook returns the number of bytes at the beginning of an\n\ |
4826 | argument that must be put in registers. The value must be zero for\n\ | |
4827 | arguments that are passed entirely in registers or that are entirely\n\ | |
4828 | pushed on the stack.\n\ | |
4829 | \n\ | |
4830 | On some machines, certain arguments must be passed partially in\n\ | |
4831 | registers and partially in memory. On these machines, typically the\n\ | |
4832 | first few words of arguments are passed in registers, and the rest\n\ | |
4833 | on the stack. If a multi-word argument (a @code{double} or a\n\ | |
4834 | structure) crosses that boundary, its first few words must be passed\n\ | |
4835 | in registers and the rest must be pushed. This macro tells the\n\ | |
4836 | compiler when this occurs, and how many bytes should go in registers.\n\ | |
4837 | \n\ | |
4838 | @code{TARGET_FUNCTION_ARG} for these arguments should return the first\n\ | |
4839 | register to be used by the caller for this argument; likewise\n\ | |
4840 | @code{TARGET_FUNCTION_INCOMING_ARG}, for the called function.", | |
a7c81bc1 RS |
4841 | int, (cumulative_args_t cum, const function_arg_info &arg), |
4842 | hook_int_CUMULATIVE_ARGS_arg_info_0) | |
38f8b050 JR |
4843 | |
4844 | /* Update the state in CA to advance past an argument in the | |
4845 | argument list. The values MODE, TYPE, and NAMED describe that | |
4846 | argument. */ | |
b25b9e8f | 4847 | DEFHOOK |
38f8b050 | 4848 | (function_arg_advance, |
673c2f63 | 4849 | "This hook updates the summarizer variable pointed to by @var{ca} to\n\ |
6930c98c | 4850 | advance past argument @var{arg} in the argument list. Once this is done,\n\ |
673c2f63 JM |
4851 | the variable @var{cum} is suitable for analyzing the @emph{following}\n\ |
4852 | argument with @code{TARGET_FUNCTION_ARG}, etc.\n\ | |
4853 | \n\ | |
4854 | This hook need not do anything if the argument in question was passed\n\ | |
4855 | on the stack. The compiler knows how to track the amount of stack space\n\ | |
4856 | used for arguments without any special help.", | |
38f8b050 | 4857 | void, |
6930c98c | 4858 | (cumulative_args_t ca, const function_arg_info &arg), |
38f8b050 JR |
4859 | default_function_arg_advance) |
4860 | ||
870118b7 RS |
4861 | DEFHOOK |
4862 | (function_arg_offset, | |
4863 | "This hook returns the number of bytes to add to the offset of an\n\ | |
4864 | argument of type @var{type} and mode @var{mode} when passed in memory.\n\ | |
4865 | This is needed for the SPU, which passes @code{char} and @code{short}\n\ | |
4866 | arguments in the preferred slot that is in the middle of the quad word\n\ | |
4867 | instead of starting at the top. The default implementation returns 0.", | |
4868 | HOST_WIDE_INT, (machine_mode mode, const_tree type), | |
4869 | default_function_arg_offset) | |
4870 | ||
76b0cbf8 RS |
4871 | DEFHOOK |
4872 | (function_arg_padding, | |
4873 | "This hook determines whether, and in which direction, to pad out\n\ | |
4874 | an argument of mode @var{mode} and type @var{type}. It returns\n\ | |
4875 | @code{PAD_UPWARD} to insert padding above the argument, @code{PAD_DOWNWARD}\n\ | |
4876 | to insert padding below the argument, or @code{PAD_NONE} to inhibit padding.\n\ | |
4877 | \n\ | |
4878 | The @emph{amount} of padding is not controlled by this hook, but by\n\ | |
4879 | @code{TARGET_FUNCTION_ARG_ROUND_BOUNDARY}. It is always just enough\n\ | |
4880 | to reach the next multiple of that boundary.\n\ | |
4881 | \n\ | |
4882 | This hook has a default definition that is right for most systems.\n\ | |
4883 | For little-endian machines, the default is to pad upward. For\n\ | |
4884 | big-endian machines, the default is to pad downward for an argument of\n\ | |
4885 | constant size shorter than an @code{int}, and upward otherwise.", | |
4886 | pad_direction, (machine_mode mode, const_tree type), | |
4887 | default_function_arg_padding) | |
4888 | ||
38f8b050 JR |
4889 | /* Return zero if the argument described by the state of CA should |
4890 | be placed on a stack, or a hard register in which to store the | |
4891 | argument. The values MODE, TYPE, and NAMED describe that | |
4892 | argument. */ | |
b25b9e8f | 4893 | DEFHOOK |
38f8b050 | 4894 | (function_arg, |
6783fdb7 RS |
4895 | "Return an RTX indicating whether function argument @var{arg} is passed\n\ |
4896 | in a register and if so, which register. Argument @var{ca} summarizes all\n\ | |
4897 | the previous arguments.\n\ | |
673c2f63 JM |
4898 | \n\ |
4899 | The return value is usually either a @code{reg} RTX for the hard\n\ | |
4900 | register in which to pass the argument, or zero to pass the argument\n\ | |
4901 | on the stack.\n\ | |
4902 | \n\ | |
4903 | The value of the expression can also be a @code{parallel} RTX@. This is\n\ | |
4904 | used when an argument is passed in multiple locations. The mode of the\n\ | |
4905 | @code{parallel} should be the mode of the entire argument. The\n\ | |
4906 | @code{parallel} holds any number of @code{expr_list} pairs; each one\n\ | |
4907 | describes where part of the argument is passed. In each\n\ | |
4908 | @code{expr_list} the first operand must be a @code{reg} RTX for the hard\n\ | |
4909 | register in which to pass this part of the argument, and the mode of the\n\ | |
4910 | register RTX indicates how large this part of the argument is. The\n\ | |
4911 | second operand of the @code{expr_list} is a @code{const_int} which gives\n\ | |
4912 | the offset in bytes into the entire argument of where this part starts.\n\ | |
4913 | As a special exception the first @code{expr_list} in the @code{parallel}\n\ | |
4914 | RTX may have a first operand of zero. This indicates that the entire\n\ | |
4915 | argument is also stored on the stack.\n\ | |
4916 | \n\ | |
4917 | The last time this hook is called, it is called with @code{MODE ==\n\ | |
4918 | VOIDmode}, and its result is passed to the @code{call} or @code{call_value}\n\ | |
4919 | pattern as operands 2 and 3 respectively.\n\ | |
4920 | \n\ | |
4921 | @cindex @file{stdarg.h} and register arguments\n\ | |
4922 | The usual way to make the ISO library @file{stdarg.h} work on a\n\ | |
4923 | machine where some arguments are usually passed in registers, is to\n\ | |
4924 | cause nameless arguments to be passed on the stack instead. This is\n\ | |
4925 | done by making @code{TARGET_FUNCTION_ARG} return 0 whenever\n\ | |
4926 | @var{named} is @code{false}.\n\ | |
4927 | \n\ | |
4928 | @cindex @code{TARGET_MUST_PASS_IN_STACK}, and @code{TARGET_FUNCTION_ARG}\n\ | |
4929 | @cindex @code{REG_PARM_STACK_SPACE}, and @code{TARGET_FUNCTION_ARG}\n\ | |
4930 | You may use the hook @code{targetm.calls.must_pass_in_stack}\n\ | |
4931 | in the definition of this macro to determine if this argument is of a\n\ | |
4932 | type that must be passed in the stack. If @code{REG_PARM_STACK_SPACE}\n\ | |
4933 | is not defined and @code{TARGET_FUNCTION_ARG} returns nonzero for such an\n\ | |
4934 | argument, the compiler will abort. If @code{REG_PARM_STACK_SPACE} is\n\ | |
4935 | defined, the argument will be computed in the stack and then loaded into\n\ | |
4936 | a register.", | |
6783fdb7 | 4937 | rtx, (cumulative_args_t ca, const function_arg_info &arg), |
38f8b050 JR |
4938 | default_function_arg) |
4939 | ||
b25b9e8f | 4940 | DEFHOOK |
38f8b050 | 4941 | (function_incoming_arg, |
4a235312 L |
4942 | "Define this hook if the caller and callee on the target have different\n\ |
4943 | views of where arguments are passed. Also define this hook if there are\n\ | |
4944 | functions that are never directly called, but are invoked by the hardware\n\ | |
4945 | and which have nonstandard calling conventions.\n\ | |
673c2f63 | 4946 | \n\ |
4a235312 | 4947 | In this case @code{TARGET_FUNCTION_ARG} computes the register in\n\ |
673c2f63 JM |
4948 | which the caller passes the value, and\n\ |
4949 | @code{TARGET_FUNCTION_INCOMING_ARG} should be defined in a similar\n\ | |
4950 | fashion to tell the function being called where the arguments will\n\ | |
4951 | arrive.\n\ | |
4952 | \n\ | |
4a235312 L |
4953 | @code{TARGET_FUNCTION_INCOMING_ARG} can also return arbitrary address\n\ |
4954 | computation using hard register, which can be forced into a register,\n\ | |
4955 | so that it can be used to pass special arguments.\n\ | |
4956 | \n\ | |
673c2f63 JM |
4957 | If @code{TARGET_FUNCTION_INCOMING_ARG} is not defined,\n\ |
4958 | @code{TARGET_FUNCTION_ARG} serves both purposes.", | |
6783fdb7 | 4959 | rtx, (cumulative_args_t ca, const function_arg_info &arg), |
38f8b050 JR |
4960 | default_function_incoming_arg) |
4961 | ||
c2ed6cf8 NF |
4962 | DEFHOOK |
4963 | (function_arg_boundary, | |
673c2f63 JM |
4964 | "This hook returns the alignment boundary, in bits, of an argument\n\ |
4965 | with the specified mode and type. The default hook returns\n\ | |
4966 | @code{PARM_BOUNDARY} for all arguments.", | |
ef4bddc2 | 4967 | unsigned int, (machine_mode mode, const_tree type), |
c2ed6cf8 NF |
4968 | default_function_arg_boundary) |
4969 | ||
123148b5 BS |
4970 | DEFHOOK |
4971 | (function_arg_round_boundary, | |
4972 | "Normally, the size of an argument is rounded up to @code{PARM_BOUNDARY},\n\ | |
4973 | which is the default value for this hook. You can define this hook to\n\ | |
4974 | return a different value if an argument size must be rounded to a larger\n\ | |
4975 | value.", | |
ef4bddc2 | 4976 | unsigned int, (machine_mode mode, const_tree type), |
123148b5 BS |
4977 | default_function_arg_round_boundary) |
4978 | ||
38f8b050 JR |
4979 | /* Return the diagnostic message string if function without a prototype |
4980 | is not allowed for this 'val' argument; NULL otherwise. */ | |
4981 | DEFHOOK | |
4982 | (invalid_arg_for_unprototyped_fn, | |
673c2f63 JM |
4983 | "If defined, this macro returns the diagnostic message when it is\n\ |
4984 | illegal to pass argument @var{val} to function @var{funcdecl}\n\ | |
4985 | with prototype @var{typelist}.", | |
38f8b050 JR |
4986 | const char *, (const_tree typelist, const_tree funcdecl, const_tree val), |
4987 | hook_invalid_arg_for_unprototyped_fn) | |
4988 | ||
4989 | /* Return an rtx for the return value location of the function | |
4990 | specified by FN_DECL_OR_TYPE with a return type of RET_TYPE. */ | |
4991 | DEFHOOK | |
4992 | (function_value, | |
673c2f63 JM |
4993 | "\n\ |
4994 | Define this to return an RTX representing the place where a function\n\ | |
4995 | returns or receives a value of data type @var{ret_type}, a tree node\n\ | |
4996 | representing a data type. @var{fn_decl_or_type} is a tree node\n\ | |
4997 | representing @code{FUNCTION_DECL} or @code{FUNCTION_TYPE} of a\n\ | |
4998 | function being called. If @var{outgoing} is false, the hook should\n\ | |
4999 | compute the register in which the caller will see the return value.\n\ | |
5000 | Otherwise, the hook should return an RTX representing the place where\n\ | |
5001 | a function returns a value.\n\ | |
5002 | \n\ | |
5003 | On many machines, only @code{TYPE_MODE (@var{ret_type})} is relevant.\n\ | |
5004 | (Actually, on most machines, scalar values are returned in the same\n\ | |
5005 | place regardless of mode.) The value of the expression is usually a\n\ | |
5006 | @code{reg} RTX for the hard register where the return value is stored.\n\ | |
5007 | The value can also be a @code{parallel} RTX, if the return value is in\n\ | |
5008 | multiple places. See @code{TARGET_FUNCTION_ARG} for an explanation of the\n\ | |
5009 | @code{parallel} form. Note that the callee will populate every\n\ | |
5010 | location specified in the @code{parallel}, but if the first element of\n\ | |
5011 | the @code{parallel} contains the whole return value, callers will use\n\ | |
5012 | that element as the canonical location and ignore the others. The m68k\n\ | |
5013 | port uses this type of @code{parallel} to return pointers in both\n\ | |
5014 | @samp{%a0} (the canonical location) and @samp{%d0}.\n\ | |
5015 | \n\ | |
5016 | If @code{TARGET_PROMOTE_FUNCTION_RETURN} returns true, you must apply\n\ | |
5017 | the same promotion rules specified in @code{PROMOTE_MODE} if\n\ | |
5018 | @var{valtype} is a scalar type.\n\ | |
5019 | \n\ | |
5020 | If the precise function being called is known, @var{func} is a tree\n\ | |
5021 | node (@code{FUNCTION_DECL}) for it; otherwise, @var{func} is a null\n\ | |
5022 | pointer. This makes it possible to use a different value-returning\n\ | |
5023 | convention for specific functions when all their calls are\n\ | |
5024 | known.\n\ | |
5025 | \n\ | |
5026 | Some target machines have ``register windows'' so that the register in\n\ | |
5027 | which a function returns its value is not the same as the one in which\n\ | |
5028 | the caller sees the value. For such machines, you should return\n\ | |
5029 | different RTX depending on @var{outgoing}.\n\ | |
5030 | \n\ | |
5031 | @code{TARGET_FUNCTION_VALUE} is not used for return values with\n\ | |
5032 | aggregate data types, because these are returned in another way. See\n\ | |
5033 | @code{TARGET_STRUCT_VALUE_RTX} and related macros, below.", | |
38f8b050 JR |
5034 | rtx, (const_tree ret_type, const_tree fn_decl_or_type, bool outgoing), |
5035 | default_function_value) | |
5036 | ||
5037 | /* Return the rtx for the result of a libcall of mode MODE, | |
5038 | calling the function FN_NAME. */ | |
5039 | DEFHOOK | |
5040 | (libcall_value, | |
673c2f63 JM |
5041 | "Define this hook if the back-end needs to know the name of the libcall\n\ |
5042 | function in order to determine where the result should be returned.\n\ | |
5043 | \n\ | |
5044 | The mode of the result is given by @var{mode} and the name of the called\n\ | |
5045 | library function is given by @var{fun}. The hook should return an RTX\n\ | |
5046 | representing the place where the library function result will be returned.\n\ | |
5047 | \n\ | |
5048 | If this hook is not defined, then LIBCALL_VALUE will be used.", | |
ef4bddc2 | 5049 | rtx, (machine_mode mode, const_rtx fun), |
38f8b050 JR |
5050 | default_libcall_value) |
5051 | ||
5052 | /* Return true if REGNO is a possible register number for | |
5053 | a function value as seen by the caller. */ | |
5054 | DEFHOOK | |
5055 | (function_value_regno_p, | |
673c2f63 JM |
5056 | "A target hook that return @code{true} if @var{regno} is the number of a hard\n\ |
5057 | register in which the values of called function may come back.\n\ | |
5058 | \n\ | |
5059 | A register whose use for returning values is limited to serving as the\n\ | |
5060 | second of a pair (for a value of type @code{double}, say) need not be\n\ | |
5061 | recognized by this target hook.\n\ | |
5062 | \n\ | |
5063 | If the machine has register windows, so that the caller and the called\n\ | |
5064 | function use different registers for the return value, this target hook\n\ | |
5065 | should recognize only the caller's register numbers.\n\ | |
5066 | \n\ | |
5067 | If this hook is not defined, then FUNCTION_VALUE_REGNO_P will be used.", | |
38f8b050 JR |
5068 | bool, (const unsigned int regno), |
5069 | default_function_value_regno_p) | |
5070 | ||
002ffd3c RS |
5071 | DEFHOOK |
5072 | (fntype_abi, | |
5073 | "Return the ABI used by a function with type @var{type}; see the\n\ | |
5074 | definition of @code{predefined_function_abi} for details of the ABI\n\ | |
5075 | descriptor. Targets only need to define this hook if they support\n\ | |
5076 | interoperability between several ABIs in the same translation unit.", | |
5077 | const predefined_function_abi &, (const_tree type), | |
5078 | NULL) | |
5079 | ||
5a5a3bc5 RS |
5080 | DEFHOOK |
5081 | (insn_callee_abi, | |
5082 | "This hook returns a description of the ABI used by the target of\n\ | |
5083 | call instruction @var{insn}; see the definition of\n\ | |
5084 | @code{predefined_function_abi} for details of the ABI descriptor.\n\ | |
5085 | Only the global function @code{insn_callee_abi} should call this hook\n\ | |
5086 | directly.\n\ | |
5087 | \n\ | |
5088 | Targets only need to define this hook if they support\n\ | |
5089 | interoperability between several ABIs in the same translation unit.", | |
5090 | const predefined_function_abi &, (const rtx_insn *insn), | |
5091 | NULL) | |
5092 | ||
38f8b050 JR |
5093 | /* ??? Documenting this hook requires a GFDL license grant. */ |
5094 | DEFHOOK_UNDOC | |
5095 | (internal_arg_pointer, | |
5096 | "Return an rtx for the argument pointer incoming to the\ | |
5097 | current function.", | |
5098 | rtx, (void), | |
5099 | default_internal_arg_pointer) | |
5100 | ||
5101 | /* Update the current function stack boundary if needed. */ | |
5102 | DEFHOOK | |
5103 | (update_stack_boundary, | |
673c2f63 JM |
5104 | "Define this macro to update the current function stack boundary if\n\ |
5105 | necessary.", | |
38f8b050 JR |
5106 | void, (void), NULL) |
5107 | ||
5108 | /* Handle stack alignment and return an rtx for Dynamic Realign | |
5109 | Argument Pointer if necessary. */ | |
5110 | DEFHOOK | |
5111 | (get_drap_rtx, | |
673c2f63 JM |
5112 | "This hook should return an rtx for Dynamic Realign Argument Pointer (DRAP) if a\n\ |
5113 | different argument pointer register is needed to access the function's\n\ | |
5114 | argument list due to stack realignment. Return @code{NULL} if no DRAP\n\ | |
5115 | is needed.", | |
38f8b050 JR |
5116 | rtx, (void), NULL) |
5117 | ||
d10f3e90 | 5118 | /* Generate instruction sequence to zero call used registers. */ |
5119 | DEFHOOK | |
5120 | (zero_call_used_regs, | |
5121 | "This target hook emits instructions to zero the subset of @var{selected_regs}\n\ | |
5122 | that could conceivably contain values that are useful to an attacker.\n\ | |
5123 | Return the set of registers that were actually cleared.\n\ | |
5124 | \n\ | |
5125 | The default implementation uses normal move instructions to zero\n\ | |
5126 | all the registers in @var{selected_regs}. Define this hook if the\n\ | |
5127 | target has more efficient ways of zeroing certain registers,\n\ | |
5128 | or if you believe that certain registers would never contain\n\ | |
5129 | values that are useful to an attacker.", | |
5130 | HARD_REG_SET, (HARD_REG_SET selected_regs), | |
5131 | default_zero_call_used_regs) | |
5132 | ||
38f8b050 JR |
5133 | /* Return true if all function parameters should be spilled to the |
5134 | stack. */ | |
5135 | DEFHOOK | |
5136 | (allocate_stack_slots_for_args, | |
673c2f63 JM |
5137 | "When optimization is disabled, this hook indicates whether or not\n\ |
5138 | arguments should be allocated to stack slots. Normally, GCC allocates\n\ | |
5139 | stacks slots for arguments when not optimizing in order to make\n\ | |
5140 | debugging easier. However, when a function is declared with\n\ | |
5141 | @code{__attribute__((naked))}, there is no stack frame, and the compiler\n\ | |
5142 | cannot safely move arguments from the registers in which they are passed\n\ | |
5143 | to the stack. Therefore, this hook should return true in general, but\n\ | |
5144 | false for naked functions. The default implementation always returns true.", | |
38f8b050 JR |
5145 | bool, (void), |
5146 | hook_bool_void_true) | |
5147 | ||
c21df29b RH |
5148 | /* Return an rtx for the static chain for FNDECL_OR_TYPE. If INCOMING_P |
5149 | is true, then it should be for the callee; otherwise for the caller. */ | |
38f8b050 JR |
5150 | DEFHOOK |
5151 | (static_chain, | |
673c2f63 JM |
5152 | "This hook replaces the use of @code{STATIC_CHAIN_REGNUM} et al for\n\ |
5153 | targets that may use different static chain locations for different\n\ | |
5154 | nested functions. This may be required if the target has function\n\ | |
5155 | attributes that affect the calling conventions of the function and\n\ | |
5156 | those calling conventions use different static chain locations.\n\ | |
5157 | \n\ | |
5158 | The default version of this hook uses @code{STATIC_CHAIN_REGNUM} et al.\n\ | |
5159 | \n\ | |
5160 | If the static chain is passed in memory, this hook should be used to\n\ | |
5161 | provide rtx giving @code{mem} expressions that denote where they are stored.\n\ | |
5162 | Often the @code{mem} expression as seen by the caller will be at an offset\n\ | |
5163 | from the stack pointer and the @code{mem} expression as seen by the callee\n\ | |
5164 | will be at an offset from the frame pointer.\n\ | |
5165 | @findex stack_pointer_rtx\n\ | |
5166 | @findex frame_pointer_rtx\n\ | |
5167 | @findex arg_pointer_rtx\n\ | |
5168 | The variables @code{stack_pointer_rtx}, @code{frame_pointer_rtx}, and\n\ | |
5169 | @code{arg_pointer_rtx} will have been initialized and should be used\n\ | |
5170 | to refer to those items.", | |
c21df29b | 5171 | rtx, (const_tree fndecl_or_type, bool incoming_p), |
38f8b050 JR |
5172 | default_static_chain) |
5173 | ||
5174 | /* Fill in the trampoline at MEM with a call to FNDECL and a | |
5175 | static chain value of CHAIN. */ | |
5176 | DEFHOOK | |
5177 | (trampoline_init, | |
673c2f63 JM |
5178 | "This hook is called to initialize a trampoline.\n\ |
5179 | @var{m_tramp} is an RTX for the memory block for the trampoline; @var{fndecl}\n\ | |
5180 | is the @code{FUNCTION_DECL} for the nested function; @var{static_chain} is an\n\ | |
5181 | RTX for the static chain value that should be passed to the function\n\ | |
5182 | when it is called.\n\ | |
5183 | \n\ | |
5184 | If the target defines @code{TARGET_ASM_TRAMPOLINE_TEMPLATE}, then the\n\ | |
5185 | first thing this hook should do is emit a block move into @var{m_tramp}\n\ | |
5186 | from the memory block returned by @code{assemble_trampoline_template}.\n\ | |
5187 | Note that the block move need only cover the constant parts of the\n\ | |
5188 | trampoline. If the target isolates the variable parts of the trampoline\n\ | |
5189 | to the end, not all @code{TRAMPOLINE_SIZE} bytes need be copied.\n\ | |
5190 | \n\ | |
c05ece92 AO |
5191 | If the target requires any other actions, such as flushing caches\n\ |
5192 | (possibly calling function maybe_emit_call_builtin___clear_cache) or\n\ | |
673c2f63 JM |
5193 | enabling stack execution, these actions should be performed after\n\ |
5194 | initializing the trampoline proper.", | |
38f8b050 JR |
5195 | void, (rtx m_tramp, tree fndecl, rtx static_chain), |
5196 | default_trampoline_init) | |
5197 | ||
c05ece92 AO |
5198 | /* Emit a call to a function to clear the instruction cache. */ |
5199 | DEFHOOK | |
5200 | (emit_call_builtin___clear_cache, | |
5201 | "On targets that do not define a @code{clear_cache} insn expander,\n\ | |
5202 | but that define the @code{CLEAR_CACHE_INSN} macro,\n\ | |
5203 | maybe_emit_call_builtin___clear_cache relies on this target hook\n\ | |
5204 | to clear an address range in the instruction cache.\n\ | |
5205 | \n\ | |
5206 | The default implementation calls the @code{__clear_cache} builtin,\n\ | |
5207 | taking the assembler name from the builtin declaration. Overriding\n\ | |
5208 | definitions may call alternate functions, with alternate calling\n\ | |
5209 | conventions, or emit alternate RTX to perform the job.", | |
5210 | void, (rtx begin, rtx end), | |
5211 | default_emit_call_builtin___clear_cache) | |
5212 | ||
38f8b050 JR |
5213 | /* Adjust the address of the trampoline in a target-specific way. */ |
5214 | DEFHOOK | |
5215 | (trampoline_adjust_address, | |
673c2f63 JM |
5216 | "This hook should perform any machine-specific adjustment in\n\ |
5217 | the address of the trampoline. Its argument contains the address of the\n\ | |
5218 | memory block that was passed to @code{TARGET_TRAMPOLINE_INIT}. In case\n\ | |
5219 | the address to be used for a function call should be different from the\n\ | |
5220 | address at which the template was stored, the different address should\n\ | |
5221 | be returned; otherwise @var{addr} should be returned unchanged.\n\ | |
5222 | If this hook is not defined, @var{addr} will be used for function calls.", | |
38f8b050 JR |
5223 | rtx, (rtx addr), NULL) |
5224 | ||
4c640e26 EB |
5225 | DEFHOOKPOD |
5226 | (custom_function_descriptors, | |
92b6df43 SL |
5227 | "If the target can use GCC's generic descriptor mechanism for nested\n\ |
5228 | functions, define this hook to a power of 2 representing an unused bit\n\ | |
5229 | in function pointers which can be used to differentiate descriptors at\n\ | |
5230 | run time. This value gives the number of bytes by which descriptor\n\ | |
5231 | pointers are misaligned compared to function pointers. For example, on\n\ | |
5232 | targets that require functions to be aligned to a 4-byte boundary, a\n\ | |
5233 | value of either 1 or 2 is appropriate unless the architecture already\n\ | |
5234 | reserves the bit for another purpose, such as on ARM.\n\ | |
5235 | \n\ | |
5236 | Define this hook to 0 if the target implements ABI support for\n\ | |
5237 | function descriptors in its standard calling sequence, like for example\n\ | |
5238 | HPPA or IA-64.\n\ | |
5239 | \n\ | |
5240 | Using descriptors for nested functions\n\ | |
4c640e26 | 5241 | eliminates the need for trampolines that reside on the stack and require\n\ |
4d3907c2 | 5242 | it to be made executable.", |
4c640e26 EB |
5243 | int, -1) |
5244 | ||
38f8b050 JR |
5245 | /* Return the number of bytes of its own arguments that a function |
5246 | pops on returning, or 0 if the function pops no arguments and the | |
5247 | caller must therefore pop them all after the function returns. */ | |
5248 | /* ??? tm.texi has no types for the parameters. */ | |
893d13d5 | 5249 | DEFHOOK |
38f8b050 | 5250 | (return_pops_args, |
673c2f63 JM |
5251 | "This target hook returns the number of bytes of its own arguments that\n\ |
5252 | a function pops on returning, or 0 if the function pops no arguments\n\ | |
5253 | and the caller must therefore pop them all after the function returns.\n\ | |
5254 | \n\ | |
5255 | @var{fundecl} is a C variable whose value is a tree node that describes\n\ | |
5256 | the function in question. Normally it is a node of type\n\ | |
5257 | @code{FUNCTION_DECL} that describes the declaration of the function.\n\ | |
5258 | From this you can obtain the @code{DECL_ATTRIBUTES} of the function.\n\ | |
5259 | \n\ | |
5260 | @var{funtype} is a C variable whose value is a tree node that\n\ | |
5261 | describes the function in question. Normally it is a node of type\n\ | |
5262 | @code{FUNCTION_TYPE} that describes the data type of the function.\n\ | |
5263 | From this it is possible to obtain the data types of the value and\n\ | |
5264 | arguments (if known).\n\ | |
5265 | \n\ | |
5266 | When a call to a library function is being considered, @var{fundecl}\n\ | |
5267 | will contain an identifier node for the library function. Thus, if\n\ | |
5268 | you need to distinguish among various library functions, you can do so\n\ | |
5269 | by their names. Note that ``library function'' in this context means\n\ | |
5270 | a function used to perform arithmetic, whose name is known specially\n\ | |
5271 | in the compiler and was not mentioned in the C code being compiled.\n\ | |
5272 | \n\ | |
5273 | @var{size} is the number of bytes of arguments passed on the\n\ | |
5274 | stack. If a variable number of bytes is passed, it is zero, and\n\ | |
5275 | argument popping will always be the responsibility of the calling function.\n\ | |
5276 | \n\ | |
5277 | On the VAX, all functions always pop their arguments, so the definition\n\ | |
5278 | of this macro is @var{size}. On the 68000, using the standard\n\ | |
5279 | calling convention, no functions pop their arguments, so the value of\n\ | |
5280 | the macro is always 0 in this case. But an alternative calling\n\ | |
5281 | convention is available in which functions that take a fixed number of\n\ | |
5282 | arguments pop them but other functions (such as @code{printf}) pop\n\ | |
5283 | nothing (the caller pops all). When this convention is in use,\n\ | |
5284 | @var{funtype} is examined to determine whether a function takes a fixed\n\ | |
5285 | number of arguments.", | |
a20c5714 | 5286 | poly_int64, (tree fundecl, tree funtype, poly_int64 size), |
38f8b050 JR |
5287 | default_return_pops_args) |
5288 | ||
ffa88471 SE |
5289 | /* Return a mode wide enough to copy any function value that might be |
5290 | returned. */ | |
5291 | DEFHOOK | |
5292 | (get_raw_result_mode, | |
4d3907c2 ML |
5293 | "This target hook returns the mode to be used when accessing raw return\n\ |
5294 | registers in @code{__builtin_return}. Define this macro if the value\n\ | |
5295 | in @var{reg_raw_mode} is not correct.", | |
ef1d3b57 | 5296 | fixed_size_mode, (int regno), |
ffa88471 SE |
5297 | default_get_reg_raw_mode) |
5298 | ||
5299 | /* Return a mode wide enough to copy any argument value that might be | |
5300 | passed. */ | |
5301 | DEFHOOK | |
5302 | (get_raw_arg_mode, | |
4d3907c2 ML |
5303 | "This target hook returns the mode to be used when accessing raw argument\n\ |
5304 | registers in @code{__builtin_apply_args}. Define this macro if the value\n\ | |
5305 | in @var{reg_raw_mode} is not correct.", | |
ef1d3b57 | 5306 | fixed_size_mode, (int regno), |
ffa88471 SE |
5307 | default_get_reg_raw_mode) |
5308 | ||
974aedcc MP |
5309 | /* Return true if a type is an empty record. */ |
5310 | DEFHOOK | |
5311 | (empty_record_p, | |
5312 | "This target hook returns true if the type is an empty record. The default\n\ | |
5313 | is to return @code{false}.", | |
5314 | bool, (const_tree type), | |
5315 | hook_bool_const_tree_false) | |
5316 | ||
5317 | /* Warn about the change in empty class parameter passing ABI. */ | |
5318 | DEFHOOK | |
5319 | (warn_parameter_passing_abi, | |
5320 | "This target hook warns about the change in empty class parameter passing\n\ | |
5321 | ABI.", | |
5322 | void, (cumulative_args_t ca, tree type), | |
5323 | hook_void_CUMULATIVE_ARGS_tree) | |
5324 | ||
38f8b050 JR |
5325 | HOOK_VECTOR_END (calls) |
5326 | ||
bcb21886 KY |
5327 | DEFHOOK |
5328 | (use_pseudo_pic_reg, | |
5329 | "This hook should return 1 in case pseudo register should be created\n\ | |
5330 | for pic_offset_table_rtx during function expand.", | |
5331 | bool, (void), | |
5332 | hook_bool_void_false) | |
5333 | ||
5334 | DEFHOOK | |
5335 | (init_pic_reg, | |
5336 | "Perform a target dependent initialization of pic_offset_table_rtx.\n\ | |
5337 | This hook is called at the start of register allocation.", | |
5338 | void, (void), | |
5339 | hook_void_void) | |
5340 | ||
38f8b050 JR |
5341 | /* Return the diagnostic message string if conversion from FROMTYPE |
5342 | to TOTYPE is not allowed, NULL otherwise. */ | |
5343 | DEFHOOK | |
5344 | (invalid_conversion, | |
673c2f63 JM |
5345 | "If defined, this macro returns the diagnostic message when it is\n\ |
5346 | invalid to convert from @var{fromtype} to @var{totype}, or @code{NULL}\n\ | |
5347 | if validity should be determined by the front end.", | |
38f8b050 JR |
5348 | const char *, (const_tree fromtype, const_tree totype), |
5349 | hook_constcharptr_const_tree_const_tree_null) | |
5350 | ||
5351 | /* Return the diagnostic message string if the unary operation OP is | |
5352 | not permitted on TYPE, NULL otherwise. */ | |
5353 | DEFHOOK | |
5354 | (invalid_unary_op, | |
673c2f63 JM |
5355 | "If defined, this macro returns the diagnostic message when it is\n\ |
5356 | invalid to apply operation @var{op} (where unary plus is denoted by\n\ | |
5357 | @code{CONVERT_EXPR}) to an operand of type @var{type}, or @code{NULL}\n\ | |
5358 | if validity should be determined by the front end.", | |
38f8b050 JR |
5359 | const char *, (int op, const_tree type), |
5360 | hook_constcharptr_int_const_tree_null) | |
5361 | ||
5362 | /* Return the diagnostic message string if the binary operation OP | |
5363 | is not permitted on TYPE1 and TYPE2, NULL otherwise. */ | |
5364 | DEFHOOK | |
5365 | (invalid_binary_op, | |
673c2f63 JM |
5366 | "If defined, this macro returns the diagnostic message when it is\n\ |
5367 | invalid to apply operation @var{op} to operands of types @var{type1}\n\ | |
5368 | and @var{type2}, or @code{NULL} if validity should be determined by\n\ | |
5369 | the front end.", | |
38f8b050 JR |
5370 | const char *, (int op, const_tree type1, const_tree type2), |
5371 | hook_constcharptr_int_const_tree_const_tree_null) | |
5372 | ||
38f8b050 JR |
5373 | /* If values of TYPE are promoted to some other type when used in |
5374 | expressions (analogous to the integer promotions), return that type, | |
5375 | or NULL_TREE otherwise. */ | |
5376 | DEFHOOK | |
5377 | (promoted_type, | |
673c2f63 JM |
5378 | "If defined, this target hook returns the type to which values of\n\ |
5379 | @var{type} should be promoted when they appear in expressions,\n\ | |
5380 | analogous to the integer promotions, or @code{NULL_TREE} to use the\n\ | |
5381 | front end's normal promotion rules. This hook is useful when there are\n\ | |
5382 | target-specific types with special promotion rules.\n\ | |
5383 | This is currently used only by the C and C++ front ends.", | |
38f8b050 JR |
5384 | tree, (const_tree type), |
5385 | hook_tree_const_tree_null) | |
5386 | ||
5387 | /* Convert EXPR to TYPE, if target-specific types with special conversion | |
5388 | rules are involved. Return the converted expression, or NULL to apply | |
5389 | the standard conversion rules. */ | |
5390 | DEFHOOK | |
5391 | (convert_to_type, | |
673c2f63 JM |
5392 | "If defined, this hook returns the result of converting @var{expr} to\n\ |
5393 | @var{type}. It should return the converted expression,\n\ | |
5394 | or @code{NULL_TREE} to apply the front end's normal conversion rules.\n\ | |
5395 | This hook is useful when there are target-specific types with special\n\ | |
5396 | conversion rules.\n\ | |
5397 | This is currently used only by the C and C++ front ends.", | |
38f8b050 JR |
5398 | tree, (tree type, tree expr), |
5399 | hook_tree_tree_tree_null) | |
5400 | ||
65ef05d0 RS |
5401 | DEFHOOK |
5402 | (verify_type_context, | |
5403 | "If defined, this hook returns false if there is a target-specific reason\n\ | |
5404 | why type @var{type} cannot be used in the source language context described\n\ | |
5405 | by @var{context}. When @var{silent_p} is false, the hook also reports an\n\ | |
5406 | error against @var{loc} for invalid uses of @var{type}.\n\ | |
5407 | \n\ | |
5408 | Calls to this hook should be made through the global function\n\ | |
5409 | @code{verify_type_context}, which makes the @var{silent_p} parameter\n\ | |
5410 | default to false and also handles @code{error_mark_node}.\n\ | |
5411 | \n\ | |
5412 | The default implementation always returns true.", | |
5413 | bool, (location_t loc, type_context_kind context, const_tree type, | |
5414 | bool silent_p), | |
5415 | NULL) | |
5416 | ||
0d803030 RS |
5417 | DEFHOOK |
5418 | (can_change_mode_class, | |
5419 | "This hook returns true if it is possible to bitcast values held in\n\ | |
5420 | registers of class @var{rclass} from mode @var{from} to mode @var{to}\n\ | |
5421 | and if doing so preserves the low-order bits that are common to both modes.\n\ | |
5422 | The result is only meaningful if @var{rclass} has registers that can hold\n\ | |
5423 | both @code{from} and @code{to}. The default implementation returns true.\n\ | |
5424 | \n\ | |
5425 | As an example of when such bitcasting is invalid, loading 32-bit integer or\n\ | |
5426 | floating-point objects into floating-point registers on Alpha extends them\n\ | |
5427 | to 64 bits. Therefore loading a 64-bit object and then storing it as a\n\ | |
5428 | 32-bit object does not store the low-order 32 bits, as would be the case\n\ | |
5429 | for a normal register. Therefore, @file{alpha.h} defines\n\ | |
5430 | @code{TARGET_CAN_CHANGE_MODE_CLASS} to return:\n\ | |
5431 | \n\ | |
5432 | @smallexample\n\ | |
5433 | (GET_MODE_SIZE (from) == GET_MODE_SIZE (to)\n\ | |
5434 | || !reg_classes_intersect_p (FLOAT_REGS, rclass))\n\ | |
5435 | @end smallexample\n\ | |
5436 | \n\ | |
5437 | Even if storing from a register in mode @var{to} would be valid,\n\ | |
5438 | if both @var{from} and @code{raw_reg_mode} for @var{rclass} are wider\n\ | |
5439 | than @code{word_mode}, then we must prevent @var{to} narrowing the\n\ | |
5440 | mode. This happens when the middle-end assumes that it can load\n\ | |
5441 | or store pieces of an @var{N}-word pseudo, and that the pseudo will\n\ | |
5442 | eventually be allocated to @var{N} @code{word_mode} hard registers.\n\ | |
5443 | Failure to prevent this kind of mode change will result in the\n\ | |
5444 | entire @code{raw_reg_mode} being modified instead of the partial\n\ | |
5445 | value that the middle-end intended.", | |
5446 | bool, (machine_mode from, machine_mode to, reg_class_t rclass), | |
5447 | hook_bool_mode_mode_reg_class_t_true) | |
5448 | ||
5074a1f8 VM |
5449 | /* Change pseudo allocno class calculated by IRA. */ |
5450 | DEFHOOK | |
5451 | (ira_change_pseudo_allocno_class, | |
5452 | "A target hook which can change allocno class for given pseudo from\n\ | |
31e2b5a3 | 5453 | allocno and best class calculated by IRA.\n\ |
5074a1f8 VM |
5454 | \n\ |
5455 | The default version of this target hook always returns given class.", | |
31e2b5a3 | 5456 | reg_class_t, (int, reg_class_t, reg_class_t), |
5074a1f8 VM |
5457 | default_ira_change_pseudo_allocno_class) |
5458 | ||
55a2c322 VM |
5459 | /* Return true if we use LRA instead of reload. */ |
5460 | DEFHOOK | |
5461 | (lra_p, | |
4d3907c2 ML |
5462 | "A target hook which returns true if we use LRA instead of reload pass.\n\ |
5463 | \n\ | |
5464 | The default version of this target hook returns true. New ports\n\ | |
5465 | should use LRA, and existing ports are encouraged to convert.", | |
55a2c322 VM |
5466 | bool, (void), |
5467 | default_lra_p) | |
5468 | ||
5469 | /* Return register priority of given hard regno for the current target. */ | |
5470 | DEFHOOK | |
5471 | (register_priority, | |
4d3907c2 ML |
5472 | "A target hook which returns the register priority number to which the\n\ |
5473 | register @var{hard_regno} belongs to. The bigger the number, the\n\ | |
5474 | more preferable the hard register usage (when all other conditions are\n\ | |
5475 | the same). This hook can be used to prefer some hard register over\n\ | |
5476 | others in LRA. For example, some x86-64 register usage needs\n\ | |
5477 | additional prefix which makes instructions longer. The hook can\n\ | |
5478 | return lower priority number for such registers make them less favorable\n\ | |
5479 | and as result making the generated code smaller.\n\ | |
5480 | \n\ | |
5481 | The default version of this target hook returns always zero.", | |
55a2c322 VM |
5482 | int, (int), |
5483 | default_register_priority) | |
5484 | ||
3b9ceb4b VM |
5485 | /* Return true if we need register usage leveling. */ |
5486 | DEFHOOK | |
5487 | (register_usage_leveling_p, | |
4d3907c2 ML |
5488 | "A target hook which returns true if we need register usage leveling.\n\ |
5489 | That means if a few hard registers are equally good for the\n\ | |
5490 | assignment, we choose the least used hard register. The register\n\ | |
5491 | usage leveling may be profitable for some targets. Don't use the\n\ | |
5492 | usage leveling for targets with conditional execution or targets\n\ | |
5493 | with big register files as it hurts if-conversion and cross-jumping\n\ | |
5494 | optimizations.\n\ | |
5495 | \n\ | |
5496 | The default version of this target hook returns always false.", | |
3b9ceb4b VM |
5497 | bool, (void), |
5498 | default_register_usage_leveling_p) | |
5499 | ||
55a2c322 VM |
5500 | /* Return true if maximal address displacement can be different. */ |
5501 | DEFHOOK | |
5502 | (different_addr_displacement_p, | |
4d3907c2 ML |
5503 | "A target hook which returns true if an address with the same structure\n\ |
5504 | can have different maximal legitimate displacement. For example, the\n\ | |
5505 | displacement can depend on memory mode or on operand combinations in\n\ | |
5506 | the insn.\n\ | |
5507 | \n\ | |
5508 | The default version of this target hook returns always false.", | |
55a2c322 VM |
5509 | bool, (void), |
5510 | default_different_addr_displacement_p) | |
5511 | ||
5512 | /* Determine class for spilling pseudos of given mode into registers | |
5513 | instead of memory. */ | |
5514 | DEFHOOK | |
5515 | (spill_class, | |
4d3907c2 ML |
5516 | "This hook defines a class of registers which could be used for spilling\n\ |
5517 | pseudos of the given mode and class, or @code{NO_REGS} if only memory\n\ | |
5518 | should be used. Not defining this hook is equivalent to returning\n\ | |
5519 | @code{NO_REGS} for all inputs.", | |
ef4bddc2 | 5520 | reg_class_t, (reg_class_t, machine_mode), |
55a2c322 VM |
5521 | NULL) |
5522 | ||
e93f30a6 VM |
5523 | /* Determine an additional allocno class. */ |
5524 | DEFHOOK | |
5525 | (additional_allocno_class_p, | |
4d3907c2 ML |
5526 | "This hook should return @code{true} if given class of registers should\n\ |
5527 | be an allocno class in any way. Usually RA uses only one register\n\ | |
5528 | class from all classes containing the same register set. In some\n\ | |
5529 | complicated cases, you need to have two or more such classes as\n\ | |
5530 | allocno ones for RA correct work. Not defining this hook is\n\ | |
5531 | equivalent to returning @code{false} for all inputs.", | |
e93f30a6 VM |
5532 | bool, (reg_class_t), |
5533 | hook_bool_reg_class_t_false) | |
5534 | ||
42e37616 DM |
5535 | DEFHOOK |
5536 | (cstore_mode, | |
4d3907c2 ML |
5537 | "This hook defines the machine mode to use for the boolean result of\n\ |
5538 | conditional store patterns. The ICODE argument is the instruction code\n\ | |
5539 | for the cstore being performed. Not definiting this hook is the same\n\ | |
5540 | as accepting the mode encoded into operand 0 of the cstore expander\n\ | |
5541 | patterns.", | |
7cc237a6 | 5542 | scalar_int_mode, (enum insn_code icode), |
42e37616 DM |
5543 | default_cstore_mode) |
5544 | ||
b4ff394c PH |
5545 | /* This target hook allows the backend to compute the register pressure |
5546 | classes to use. */ | |
5547 | DEFHOOK | |
5548 | (compute_pressure_classes, | |
4d3907c2 ML |
5549 | "A target hook which lets a backend compute the set of pressure classes to\n\ |
5550 | be used by those optimization passes which take register pressure into\n\ | |
5551 | account, as opposed to letting IRA compute them. It returns the number of\n\ | |
5552 | register classes stored in the array @var{pressure_classes}.", | |
b4ff394c PH |
5553 | int, (enum reg_class *pressure_classes), NULL) |
5554 | ||
d9886a9e L |
5555 | /* True if a structure, union or array with MODE containing FIELD should |
5556 | be accessed using BLKmode. */ | |
5557 | DEFHOOK | |
5558 | (member_type_forces_blk, | |
673c2f63 JM |
5559 | "Return true if a structure, union or array containing @var{field} should\n\ |
5560 | be accessed using @code{BLKMODE}.\n\ | |
5561 | \n\ | |
5562 | If @var{field} is the only field in the structure, @var{mode} is its\n\ | |
5563 | mode, otherwise @var{mode} is VOIDmode. @var{mode} is provided in the\n\ | |
5564 | case where structures of one field would require the structure's mode to\n\ | |
5565 | retain the field's mode.\n\ | |
5566 | \n\ | |
5567 | Normally, this is not needed.", | |
ef4bddc2 | 5568 | bool, (const_tree field, machine_mode mode), |
d9886a9e L |
5569 | default_member_type_forces_blk) |
5570 | ||
e53b6e56 | 5571 | /* See tree-ssa-math-opts.cc:divmod_candidate_p for conditions |
e72531b9 PK |
5572 | that gate the divod transform. */ |
5573 | DEFHOOK | |
5574 | (expand_divmod_libfunc, | |
5575 | "Define this hook for enabling divmod transform if the port does not have\n\ | |
4d3907c2 | 5576 | hardware divmod insn but defines target-specific divmod libfuncs.", |
e72531b9 PK |
5577 | void, (rtx libfunc, machine_mode mode, rtx op0, rtx op1, rtx *quot, rtx *rem), |
5578 | NULL) | |
5579 | ||
38f8b050 JR |
5580 | /* Return the class for a secondary reload, and fill in extra information. */ |
5581 | DEFHOOK | |
5582 | (secondary_reload, | |
673c2f63 JM |
5583 | "Many machines have some registers that cannot be copied directly to or\n\ |
5584 | from memory or even from other types of registers. An example is the\n\ | |
5585 | @samp{MQ} register, which on most machines, can only be copied to or\n\ | |
5586 | from general registers, but not memory. Below, we shall be using the\n\ | |
5587 | term 'intermediate register' when a move operation cannot be performed\n\ | |
5588 | directly, but has to be done by copying the source into the intermediate\n\ | |
5589 | register first, and then copying the intermediate register to the\n\ | |
5590 | destination. An intermediate register always has the same mode as\n\ | |
5591 | source and destination. Since it holds the actual value being copied,\n\ | |
5592 | reload might apply optimizations to re-use an intermediate register\n\ | |
5593 | and eliding the copy from the source when it can determine that the\n\ | |
5594 | intermediate register still holds the required value.\n\ | |
5595 | \n\ | |
5596 | Another kind of secondary reload is required on some machines which\n\ | |
5597 | allow copying all registers to and from memory, but require a scratch\n\ | |
5598 | register for stores to some memory locations (e.g., those with symbolic\n\ | |
5599 | address on the RT, and those with certain symbolic address on the SPARC\n\ | |
5600 | when compiling PIC)@. Scratch registers need not have the same mode\n\ | |
5601 | as the value being copied, and usually hold a different value than\n\ | |
5602 | that being copied. Special patterns in the md file are needed to\n\ | |
5603 | describe how the copy is performed with the help of the scratch register;\n\ | |
5604 | these patterns also describe the number, register class(es) and mode(s)\n\ | |
5605 | of the scratch register(s).\n\ | |
5606 | \n\ | |
5607 | In some cases, both an intermediate and a scratch register are required.\n\ | |
5608 | \n\ | |
5609 | For input reloads, this target hook is called with nonzero @var{in_p},\n\ | |
5610 | and @var{x} is an rtx that needs to be copied to a register of class\n\ | |
5611 | @var{reload_class} in @var{reload_mode}. For output reloads, this target\n\ | |
5612 | hook is called with zero @var{in_p}, and a register of class @var{reload_class}\n\ | |
5613 | needs to be copied to rtx @var{x} in @var{reload_mode}.\n\ | |
5614 | \n\ | |
5615 | If copying a register of @var{reload_class} from/to @var{x} requires\n\ | |
5616 | an intermediate register, the hook @code{secondary_reload} should\n\ | |
5617 | return the register class required for this intermediate register.\n\ | |
5618 | If no intermediate register is required, it should return NO_REGS.\n\ | |
5619 | If more than one intermediate register is required, describe the one\n\ | |
5620 | that is closest in the copy chain to the reload register.\n\ | |
5621 | \n\ | |
5622 | If scratch registers are needed, you also have to describe how to\n\ | |
5623 | perform the copy from/to the reload register to/from this\n\ | |
5624 | closest intermediate register. Or if no intermediate register is\n\ | |
5625 | required, but still a scratch register is needed, describe the\n\ | |
5626 | copy from/to the reload register to/from the reload operand @var{x}.\n\ | |
5627 | \n\ | |
5628 | You do this by setting @code{sri->icode} to the instruction code of a pattern\n\ | |
5629 | in the md file which performs the move. Operands 0 and 1 are the output\n\ | |
5630 | and input of this copy, respectively. Operands from operand 2 onward are\n\ | |
5631 | for scratch operands. These scratch operands must have a mode, and a\n\ | |
5632 | single-register-class\n\ | |
5633 | @c [later: or memory]\n\ | |
5634 | output constraint.\n\ | |
5635 | \n\ | |
5636 | When an intermediate register is used, the @code{secondary_reload}\n\ | |
5637 | hook will be called again to determine how to copy the intermediate\n\ | |
5638 | register to/from the reload operand @var{x}, so your hook must also\n\ | |
5639 | have code to handle the register class of the intermediate operand.\n\ | |
5640 | \n\ | |
5641 | @c [For later: maybe we'll allow multi-alternative reload patterns -\n\ | |
5642 | @c the port maintainer could name a mov<mode> pattern that has clobbers -\n\ | |
5643 | @c and match the constraints of input and output to determine the required\n\ | |
5644 | @c alternative. A restriction would be that constraints used to match\n\ | |
5645 | @c against reloads registers would have to be written as register class\n\ | |
5646 | @c constraints, or we need a new target macro / hook that tells us if an\n\ | |
5647 | @c arbitrary constraint can match an unknown register of a given class.\n\ | |
5648 | @c Such a macro / hook would also be useful in other places.]\n\ | |
5649 | \n\ | |
5650 | \n\ | |
5651 | @var{x} might be a pseudo-register or a @code{subreg} of a\n\ | |
5652 | pseudo-register, which could either be in a hard register or in memory.\n\ | |
5653 | Use @code{true_regnum} to find out; it will return @minus{}1 if the pseudo is\n\ | |
5654 | in memory and the hard register number if it is in a register.\n\ | |
5655 | \n\ | |
5656 | Scratch operands in memory (constraint @code{\"=m\"} / @code{\"=&m\"}) are\n\ | |
5657 | currently not supported. For the time being, you will have to continue\n\ | |
f15643d4 | 5658 | to use @code{TARGET_SECONDARY_MEMORY_NEEDED} for that purpose.\n\ |
673c2f63 JM |
5659 | \n\ |
5660 | @code{copy_cost} also uses this target hook to find out how values are\n\ | |
5661 | copied. If you want it to include some extra cost for the need to allocate\n\ | |
5662 | (a) scratch register(s), set @code{sri->extra_cost} to the additional cost.\n\ | |
5663 | Or if two dependent moves are supposed to have a lower cost than the sum\n\ | |
5664 | of the individual moves due to expected fortuitous scheduling and/or special\n\ | |
5665 | forwarding logic, you can set @code{sri->extra_cost} to a negative amount.", | |
a87cf97e | 5666 | reg_class_t, |
ef4bddc2 | 5667 | (bool in_p, rtx x, reg_class_t reload_class, machine_mode reload_mode, |
38f8b050 JR |
5668 | secondary_reload_info *sri), |
5669 | default_secondary_reload) | |
5670 | ||
f15643d4 RS |
5671 | DEFHOOK |
5672 | (secondary_memory_needed, | |
5673 | "Certain machines have the property that some registers cannot be copied\n\ | |
5674 | to some other registers without using memory. Define this hook on\n\ | |
5675 | those machines to return true if objects of mode @var{m} in registers\n\ | |
5676 | of @var{class1} can only be copied to registers of class @var{class2} by\n\ | |
5677 | storing a register of @var{class1} into memory and loading that memory\n\ | |
5678 | location into a register of @var{class2}. The default definition returns\n\ | |
5679 | false for all inputs.", | |
5680 | bool, (machine_mode mode, reg_class_t class1, reg_class_t class2), | |
5681 | hook_bool_mode_reg_class_t_reg_class_t_false) | |
5682 | ||
94e23f53 RS |
5683 | DEFHOOK |
5684 | (secondary_memory_needed_mode, | |
f15643d4 | 5685 | "If @code{TARGET_SECONDARY_MEMORY_NEEDED} tells the compiler to use memory\n\ |
94e23f53 RS |
5686 | when moving between two particular registers of mode @var{mode},\n\ |
5687 | this hook specifies the mode that the memory should have.\n\ | |
5688 | \n\ | |
5689 | The default depends on @code{TARGET_LRA_P}. Without LRA, the default\n\ | |
5690 | is to use a word-sized mode for integral modes that are smaller than a\n\ | |
5691 | a word. This is right thing to do on most machines because it ensures\n\ | |
5692 | that all bits of the register are copied and prevents accesses to the\n\ | |
5693 | registers in a narrower mode, which some machines prohibit for\n\ | |
5694 | floating-point registers.\n\ | |
5695 | \n\ | |
5696 | However, this default behavior is not correct on some machines, such as\n\ | |
5697 | the DEC Alpha, that store short integers in floating-point registers\n\ | |
5698 | differently than in integer registers. On those machines, the default\n\ | |
5699 | widening will not work correctly and you must define this hook to\n\ | |
e53b6e56 | 5700 | suppress that widening in some cases. See the file @file{alpha.cc} for\n\ |
94e23f53 RS |
5701 | details.\n\ |
5702 | \n\ | |
5703 | With LRA, the default is to use @var{mode} unmodified.", | |
5704 | machine_mode, (machine_mode mode), | |
5705 | default_secondary_memory_needed_mode) | |
5706 | ||
fba42e24 AS |
5707 | /* Given an rtx X being reloaded into a reg required to be in class CLASS, |
5708 | return the class of reg to actually use. */ | |
5709 | DEFHOOK | |
5710 | (preferred_reload_class, | |
673c2f63 JM |
5711 | "A target hook that places additional restrictions on the register class\n\ |
5712 | to use when it is necessary to copy value @var{x} into a register in class\n\ | |
5713 | @var{rclass}. The value is a register class; perhaps @var{rclass}, or perhaps\n\ | |
5714 | another, smaller class.\n\ | |
5715 | \n\ | |
5716 | The default version of this hook always returns value of @code{rclass} argument.\n\ | |
5717 | \n\ | |
5718 | Sometimes returning a more restrictive class makes better code. For\n\ | |
5719 | example, on the 68000, when @var{x} is an integer constant that is in range\n\ | |
5720 | for a @samp{moveq} instruction, the value of this macro is always\n\ | |
5721 | @code{DATA_REGS} as long as @var{rclass} includes the data registers.\n\ | |
5722 | Requiring a data register guarantees that a @samp{moveq} will be used.\n\ | |
5723 | \n\ | |
5724 | One case where @code{TARGET_PREFERRED_RELOAD_CLASS} must not return\n\ | |
5725 | @var{rclass} is if @var{x} is a legitimate constant which cannot be\n\ | |
5726 | loaded into some register class. By returning @code{NO_REGS} you can\n\ | |
5727 | force @var{x} into a memory location. For example, rs6000 can load\n\ | |
5728 | immediate values into general-purpose registers, but does not have an\n\ | |
5729 | instruction for loading an immediate value into a floating-point\n\ | |
5730 | register, so @code{TARGET_PREFERRED_RELOAD_CLASS} returns @code{NO_REGS} when\n\ | |
5731 | @var{x} is a floating-point constant. If the constant can't be loaded\n\ | |
5732 | into any kind of register, code generation will be better if\n\ | |
5733 | @code{TARGET_LEGITIMATE_CONSTANT_P} makes the constant illegitimate instead\n\ | |
5734 | of using @code{TARGET_PREFERRED_RELOAD_CLASS}.\n\ | |
5735 | \n\ | |
5736 | If an insn has pseudos in it after register allocation, reload will go\n\ | |
5737 | through the alternatives and call repeatedly @code{TARGET_PREFERRED_RELOAD_CLASS}\n\ | |
5738 | to find the best one. Returning @code{NO_REGS}, in this case, makes\n\ | |
5739 | reload add a @code{!} in front of the constraint: the x86 back-end uses\n\ | |
5740 | this feature to discourage usage of 387 registers when math is done in\n\ | |
5741 | the SSE registers (and vice versa).", | |
fba42e24 AS |
5742 | reg_class_t, |
5743 | (rtx x, reg_class_t rclass), | |
5744 | default_preferred_reload_class) | |
5745 | ||
abd26bfb AS |
5746 | /* Like TARGET_PREFERRED_RELOAD_CLASS, but for output reloads instead of |
5747 | input reloads. */ | |
5748 | DEFHOOK | |
5749 | (preferred_output_reload_class, | |
673c2f63 JM |
5750 | "Like @code{TARGET_PREFERRED_RELOAD_CLASS}, but for output reloads instead of\n\ |
5751 | input reloads.\n\ | |
5752 | \n\ | |
5753 | The default version of this hook always returns value of @code{rclass}\n\ | |
5754 | argument.\n\ | |
5755 | \n\ | |
5756 | You can also use @code{TARGET_PREFERRED_OUTPUT_RELOAD_CLASS} to discourage\n\ | |
5757 | reload from using some alternatives, like @code{TARGET_PREFERRED_RELOAD_CLASS}.", | |
abd26bfb AS |
5758 | reg_class_t, |
5759 | (rtx x, reg_class_t rclass), | |
5760 | default_preferred_output_reload_class) | |
5761 | ||
5cce8171 RS |
5762 | DEFHOOK |
5763 | (select_early_remat_modes, | |
5764 | "On some targets, certain modes cannot be held in registers around a\n\ | |
5765 | standard ABI call and are relatively expensive to spill to the stack.\n\ | |
5766 | The early rematerialization pass can help in such cases by aggressively\n\ | |
5767 | recomputing values after calls, so that they don't need to be spilled.\n\ | |
5768 | \n\ | |
5769 | This hook returns the set of such modes by setting the associated bits\n\ | |
5770 | in @var{modes}. The default implementation selects no modes, which has\n\ | |
5771 | the effect of disabling the early rematerialization pass.", | |
5772 | void, (sbitmap modes), | |
5773 | default_select_early_remat_modes) | |
5774 | ||
07b8f0a8 AS |
5775 | DEFHOOK |
5776 | (class_likely_spilled_p, | |
673c2f63 JM |
5777 | "A target hook which returns @code{true} if pseudos that have been assigned\n\ |
5778 | to registers of class @var{rclass} would likely be spilled because\n\ | |
5779 | registers of @var{rclass} are needed for spill registers.\n\ | |
5780 | \n\ | |
5781 | The default version of this target hook returns @code{true} if @var{rclass}\n\ | |
5782 | has exactly one register and @code{false} otherwise. On most machines, this\n\ | |
5783 | default should be used. For generally register-starved machines, such as\n\ | |
5784 | i386, or machines with right register constraints, such as SH, this hook\n\ | |
5785 | can be used to avoid excessive spilling.\n\ | |
5786 | \n\ | |
5787 | This hook is also used by some of the global intra-procedural code\n\ | |
5788 | transformations to throtle code motion, to avoid increasing register\n\ | |
5789 | pressure.", | |
07b8f0a8 AS |
5790 | bool, (reg_class_t rclass), |
5791 | default_class_likely_spilled_p) | |
5792 | ||
a8c44c52 AS |
5793 | /* Return the maximum number of consecutive registers |
5794 | needed to represent mode MODE in a register of class RCLASS. */ | |
5795 | DEFHOOK | |
5796 | (class_max_nregs, | |
673c2f63 JM |
5797 | "A target hook returns the maximum number of consecutive registers\n\ |
5798 | of class @var{rclass} needed to hold a value of mode @var{mode}.\n\ | |
5799 | \n\ | |
c43f4279 RS |
5800 | This is closely related to the macro @code{TARGET_HARD_REGNO_NREGS}.\n\ |
5801 | In fact, the value returned by @code{TARGET_CLASS_MAX_NREGS (@var{rclass},\n\ | |
673c2f63 | 5802 | @var{mode})} target hook should be the maximum value of\n\ |
c43f4279 | 5803 | @code{TARGET_HARD_REGNO_NREGS (@var{regno}, @var{mode})} for all @var{regno}\n\ |
673c2f63 JM |
5804 | values in the class @var{rclass}.\n\ |
5805 | \n\ | |
5806 | This target hook helps control the handling of multiple-word values\n\ | |
5807 | in the reload pass.\n\ | |
5808 | \n\ | |
5809 | The default version of this target hook returns the size of @var{mode}\n\ | |
5810 | in words.", | |
ef4bddc2 | 5811 | unsigned char, (reg_class_t rclass, machine_mode mode), |
a8c44c52 AS |
5812 | default_class_max_nregs) |
5813 | ||
5f286f4a YQ |
5814 | DEFHOOK |
5815 | (preferred_rename_class, | |
4d3907c2 ML |
5816 | "A target hook that places additional preference on the register\n\ |
5817 | class to use when it is necessary to rename a register in class\n\ | |
5818 | @var{rclass} to another class, or perhaps @var{NO_REGS}, if no\n\ | |
5819 | preferred register class is found or hook @code{preferred_rename_class}\n\ | |
5820 | is not implemented.\n\ | |
5821 | Sometimes returning a more restrictive class makes better code. For\n\ | |
5822 | example, on ARM, thumb-2 instructions using @code{LO_REGS} may be\n\ | |
5823 | smaller than instructions using @code{GENERIC_REGS}. By returning\n\ | |
5824 | @code{LO_REGS} from @code{preferred_rename_class}, code size can\n\ | |
5825 | be reduced.", | |
5f286f4a YQ |
5826 | reg_class_t, (reg_class_t rclass), |
5827 | default_preferred_rename_class) | |
5828 | ||
d6220b11 KK |
5829 | /* This target hook allows the backend to avoid unsafe substitution |
5830 | during register allocation. */ | |
5831 | DEFHOOK | |
5832 | (cannot_substitute_mem_equiv_p, | |
5833 | "A target hook which returns @code{true} if @var{subst} can't\n\ | |
5834 | substitute safely pseudos with equivalent memory values during\n\ | |
5835 | register allocation.\n\ | |
5836 | The default version of this target hook returns @code{false}.\n\ | |
5837 | On most machines, this default should be used. For generally\n\ | |
5838 | machines with non orthogonal register usage for addressing, such\n\ | |
5839 | as SH, this hook can be used to avoid excessive spilling.", | |
5840 | bool, (rtx subst), | |
5841 | hook_bool_rtx_false) | |
5842 | ||
14133a4d KK |
5843 | /* This target hook allows the backend to legitimize base plus |
5844 | displacement addressing. */ | |
5845 | DEFHOOK | |
5846 | (legitimize_address_displacement, | |
9005477f RS |
5847 | "This hook tries to split address offset @var{orig_offset} into\n\ |
5848 | two parts: one that should be added to the base address to create\n\ | |
5849 | a local anchor point, and an additional offset that can be applied\n\ | |
5850 | to the anchor to address a value of mode @var{mode}. The idea is that\n\ | |
5851 | the local anchor could be shared by other accesses to nearby locations.\n\ | |
5852 | \n\ | |
5853 | The hook returns true if it succeeds, storing the offset of the\n\ | |
5854 | anchor from the base in @var{offset1} and the offset of the final address\n\ | |
5855 | from the anchor in @var{offset2}. The default implementation returns false.", | |
5856 | bool, (rtx *offset1, rtx *offset2, poly_int64 orig_offset, machine_mode mode), | |
14133a4d KK |
5857 | default_legitimize_address_displacement) |
5858 | ||
38f8b050 JR |
5859 | /* This target hook allows the backend to perform additional |
5860 | processing while initializing for variable expansion. */ | |
5861 | DEFHOOK | |
5862 | (expand_to_rtl_hook, | |
673c2f63 JM |
5863 | "This hook is called just before expansion into rtl, allowing the target\n\ |
5864 | to perform additional initializations or analysis before the expansion.\n\ | |
5865 | For example, the rs6000 port uses it to allocate a scratch stack slot\n\ | |
5866 | for use in copying SDmode values between memory and floating point\n\ | |
5867 | registers whenever the function being expanded has any SDmode\n\ | |
5868 | usage.", | |
38f8b050 JR |
5869 | void, (void), |
5870 | hook_void_void) | |
5871 | ||
5872 | /* This target hook allows the backend to perform additional | |
5873 | instantiations on rtx that are not actually in insns yet, | |
5874 | but will be later. */ | |
5875 | DEFHOOK | |
5876 | (instantiate_decls, | |
673c2f63 JM |
5877 | "This hook allows the backend to perform additional instantiations on rtl\n\ |
5878 | that are not actually in any insns yet, but will be later.", | |
38f8b050 JR |
5879 | void, (void), |
5880 | hook_void_void) | |
5881 | ||
c43f4279 RS |
5882 | DEFHOOK |
5883 | (hard_regno_nregs, | |
5884 | "This hook returns the number of consecutive hard registers, starting\n\ | |
5885 | at register number @var{regno}, required to hold a value of mode\n\ | |
5886 | @var{mode}. This hook must never return zero, even if a register\n\ | |
5887 | cannot hold the requested mode - indicate that with\n\ | |
0d803030 RS |
5888 | @code{TARGET_HARD_REGNO_MODE_OK} and/or\n\ |
5889 | @code{TARGET_CAN_CHANGE_MODE_CLASS} instead.\n\ | |
c43f4279 RS |
5890 | \n\ |
5891 | The default definition returns the number of words in @var{mode}.", | |
5892 | unsigned int, (unsigned int regno, machine_mode mode), | |
5893 | default_hard_regno_nregs) | |
5894 | ||
f939c3e6 RS |
5895 | DEFHOOK |
5896 | (hard_regno_mode_ok, | |
5897 | "This hook returns true if it is permissible to store a value\n\ | |
5898 | of mode @var{mode} in hard register number @var{regno} (or in several\n\ | |
5899 | registers starting with that one). The default definition returns true\n\ | |
5900 | unconditionally.\n\ | |
5901 | \n\ | |
5902 | You need not include code to check for the numbers of fixed registers,\n\ | |
5903 | because the allocation mechanism considers them to be always occupied.\n\ | |
5904 | \n\ | |
5905 | @cindex register pairs\n\ | |
5906 | On some machines, double-precision values must be kept in even/odd\n\ | |
5907 | register pairs. You can implement that by defining this hook to reject\n\ | |
5908 | odd register numbers for such modes.\n\ | |
5909 | \n\ | |
5910 | The minimum requirement for a mode to be OK in a register is that the\n\ | |
5911 | @samp{mov@var{mode}} instruction pattern support moves between the\n\ | |
5912 | register and other hard register in the same class and that moving a\n\ | |
5913 | value into the register and back out not alter it.\n\ | |
5914 | \n\ | |
5915 | Since the same instruction used to move @code{word_mode} will work for\n\ | |
5916 | all narrower integer modes, it is not necessary on any machine for\n\ | |
5917 | this hook to distinguish between these modes, provided you define\n\ | |
5918 | patterns @samp{movhi}, etc., to take advantage of this. This is\n\ | |
5919 | useful because of the interaction between @code{TARGET_HARD_REGNO_MODE_OK}\n\ | |
99e1629f RS |
5920 | and @code{TARGET_MODES_TIEABLE_P}; it is very desirable for all integer\n\ |
5921 | modes to be tieable.\n\ | |
f939c3e6 RS |
5922 | \n\ |
5923 | Many machines have special registers for floating point arithmetic.\n\ | |
5924 | Often people assume that floating point machine modes are allowed only\n\ | |
5925 | in floating point registers. This is not true. Any registers that\n\ | |
5926 | can hold integers can safely @emph{hold} a floating point machine\n\ | |
5927 | mode, whether or not floating arithmetic can be done on it in those\n\ | |
5928 | registers. Integer move instructions can be used to move the values.\n\ | |
5929 | \n\ | |
5930 | On some machines, though, the converse is true: fixed-point machine\n\ | |
5931 | modes may not go in floating registers. This is true if the floating\n\ | |
5932 | registers normalize any value stored in them, because storing a\n\ | |
5933 | non-floating value there would garble it. In this case,\n\ | |
5934 | @code{TARGET_HARD_REGNO_MODE_OK} should reject fixed-point machine modes in\n\ | |
5935 | floating registers. But if the floating registers do not automatically\n\ | |
5936 | normalize, if you can store any bit pattern in one and retrieve it\n\ | |
5937 | unchanged without a trap, then any machine mode may go in a floating\n\ | |
5938 | register, so you can define this hook to say so.\n\ | |
5939 | \n\ | |
5940 | The primary significance of special floating registers is rather that\n\ | |
5941 | they are the registers acceptable in floating point arithmetic\n\ | |
5942 | instructions. However, this is of no concern to\n\ | |
5943 | @code{TARGET_HARD_REGNO_MODE_OK}. You handle it by writing the proper\n\ | |
5944 | constraints for those instructions.\n\ | |
5945 | \n\ | |
5946 | On some machines, the floating registers are especially slow to access,\n\ | |
5947 | so that it is better to store a value in a stack frame than in such a\n\ | |
5948 | register if floating point arithmetic is not being done. As long as the\n\ | |
5949 | floating registers are not in class @code{GENERAL_REGS}, they will not\n\ | |
5950 | be used unless some pattern's constraint asks for one.", | |
5951 | bool, (unsigned int regno, machine_mode mode), | |
5952 | hook_bool_uint_mode_true) | |
5953 | ||
99e1629f RS |
5954 | DEFHOOK |
5955 | (modes_tieable_p, | |
5956 | "This hook returns true if a value of mode @var{mode1} is accessible\n\ | |
5957 | in mode @var{mode2} without copying.\n\ | |
5958 | \n\ | |
5959 | If @code{TARGET_HARD_REGNO_MODE_OK (@var{r}, @var{mode1})} and\n\ | |
5960 | @code{TARGET_HARD_REGNO_MODE_OK (@var{r}, @var{mode2})} are always\n\ | |
5961 | the same for any @var{r}, then\n\ | |
5962 | @code{TARGET_MODES_TIEABLE_P (@var{mode1}, @var{mode2})}\n\ | |
5963 | should be true. If they differ for any @var{r}, you should define\n\ | |
5964 | this hook to return false unless some other mechanism ensures the\n\ | |
5965 | accessibility of the value in a narrower mode.\n\ | |
5966 | \n\ | |
5967 | You should define this hook to return true in as many cases as\n\ | |
5968 | possible since doing so will allow GCC to perform better register\n\ | |
5969 | allocation. The default definition returns true unconditionally.", | |
5970 | bool, (machine_mode mode1, machine_mode mode2), | |
5971 | hook_bool_mode_mode_true) | |
5972 | ||
38f8b050 JR |
5973 | /* Return true if is OK to use a hard register REGNO as scratch register |
5974 | in peephole2. */ | |
5975 | DEFHOOK | |
5976 | (hard_regno_scratch_ok, | |
673c2f63 JM |
5977 | "This target hook should return @code{true} if it is OK to use a hard register\n\ |
5978 | @var{regno} as scratch reg in peephole2.\n\ | |
5979 | \n\ | |
5980 | One common use of this macro is to prevent using of a register that\n\ | |
5981 | is not saved by a prologue in an interrupt handler.\n\ | |
5982 | \n\ | |
5983 | The default version of this hook always returns @code{true}.", | |
38f8b050 JR |
5984 | bool, (unsigned int regno), |
5985 | default_hard_regno_scratch_ok) | |
5986 | ||
80ec73f4 RS |
5987 | DEFHOOK |
5988 | (hard_regno_call_part_clobbered, | |
6ee2cc70 RS |
5989 | "ABIs usually specify that calls must preserve the full contents\n\ |
5990 | of a particular register, or that calls can alter any part of a\n\ | |
5991 | particular register. This information is captured by the target macro\n\ | |
5992 | @code{CALL_REALLY_USED_REGISTERS}. However, some ABIs specify that calls\n\ | |
5993 | must preserve certain bits of a particular register but can alter others.\n\ | |
5994 | This hook should return true if this applies to at least one of the\n\ | |
5995 | registers in @samp{(reg:@var{mode} @var{regno})}, and if as a result the\n\ | |
5996 | call would alter part of the @var{mode} value. For example, if a call\n\ | |
5997 | preserves the low 32 bits of a 64-bit hard register @var{regno} but can\n\ | |
5998 | clobber the upper 32 bits, this hook should return true for a 64-bit mode\n\ | |
5999 | but false for a 32-bit mode.\n\ | |
6000 | \n\ | |
6001 | The value of @var{abi_id} comes from the @code{predefined_function_abi}\n\ | |
6002 | structure that describes the ABI of the call; see the definition of the\n\ | |
6003 | structure for more details. If (as is usual) the target uses the same ABI\n\ | |
6004 | for all functions in a translation unit, @var{abi_id} is always 0.\n\ | |
80ec73f4 RS |
6005 | \n\ |
6006 | The default implementation returns false, which is correct\n\ | |
6007 | for targets that don't have partly call-clobbered registers.", | |
6ee2cc70 RS |
6008 | bool, (unsigned int abi_id, unsigned int regno, machine_mode mode), |
6009 | hook_bool_uint_uint_mode_false) | |
473574ee | 6010 | |
e8cecccc ML |
6011 | DEFHOOK |
6012 | (get_multilib_abi_name, | |
6013 | "This hook returns name of multilib ABI name.", | |
6014 | const char *, (void), | |
6015 | hook_constcharptr_void_null) | |
6016 | ||
38f8b050 JR |
6017 | /* Return the smallest number of different values for which it is best to |
6018 | use a jump-table instead of a tree of conditional branches. */ | |
6019 | DEFHOOK | |
6020 | (case_values_threshold, | |
673c2f63 JM |
6021 | "This function return the smallest number of different values for which it\n\ |
6022 | is best to use a jump-table instead of a tree of conditional branches.\n\ | |
6023 | The default is four for machines with a @code{casesi} instruction and\n\ | |
6024 | five otherwise. This is best for most machines.", | |
38f8b050 JR |
6025 | unsigned int, (void), |
6026 | default_case_values_threshold) | |
6027 | ||
2a31c321 RS |
6028 | DEFHOOK |
6029 | (starting_frame_offset, | |
6030 | "This hook returns the offset from the frame pointer to the first local\n\ | |
6031 | variable slot to be allocated. If @code{FRAME_GROWS_DOWNWARD}, it is the\n\ | |
6032 | offset to @emph{end} of the first slot allocated, otherwise it is the\n\ | |
6033 | offset to @emph{beginning} of the first slot allocated. The default\n\ | |
6034 | implementation returns 0.", | |
6035 | HOST_WIDE_INT, (void), | |
6036 | hook_hwi_void_0) | |
6037 | ||
29eb9a44 BE |
6038 | /* Optional callback to advise the target to compute the frame layout. */ |
6039 | DEFHOOK | |
6040 | (compute_frame_layout, | |
6041 | "This target hook is called once each time the frame layout needs to be\n\ | |
6042 | recalculated. The calculations can be cached by the target and can then\n\ | |
6043 | be used by @code{INITIAL_ELIMINATION_OFFSET} instead of re-computing the\n\ | |
6044 | layout on every invocation of that hook. This is particularly useful\n\ | |
6045 | for targets that have an expensive frame layout function. Implementing\n\ | |
6046 | this callback is optional.", | |
6047 | void, (void), | |
6048 | hook_void_void) | |
6049 | ||
53680238 | 6050 | /* Return true if a function must have and use a frame pointer. */ |
38f8b050 JR |
6051 | DEFHOOK |
6052 | (frame_pointer_required, | |
673c2f63 JM |
6053 | "This target hook should return @code{true} if a function must have and use\n\ |
6054 | a frame pointer. This target hook is called in the reload pass. If its return\n\ | |
6055 | value is @code{true} the function will have a frame pointer.\n\ | |
6056 | \n\ | |
6057 | This target hook can in principle examine the current function and decide\n\ | |
6058 | according to the facts, but on most machines the constant @code{false} or the\n\ | |
6059 | constant @code{true} suffices. Use @code{false} when the machine allows code\n\ | |
6060 | to be generated with no frame pointer, and doing so saves some time or space.\n\ | |
6061 | Use @code{true} when there is no possible advantage to avoiding a frame\n\ | |
6062 | pointer.\n\ | |
6063 | \n\ | |
6064 | In certain cases, the compiler does not know how to produce valid code\n\ | |
6065 | without a frame pointer. The compiler recognizes those cases and\n\ | |
6066 | automatically gives the function a frame pointer regardless of what\n\ | |
53680238 | 6067 | @code{targetm.frame_pointer_required} returns. You don't need to worry about\n\ |
673c2f63 JM |
6068 | them.\n\ |
6069 | \n\ | |
6070 | In a function that does not require a frame pointer, the frame pointer\n\ | |
6071 | register can be allocated for ordinary usage, unless you mark it as a\n\ | |
6072 | fixed register. See @code{FIXED_REGISTERS} for more information.\n\ | |
6073 | \n\ | |
6074 | Default return value is @code{false}.", | |
38f8b050 JR |
6075 | bool, (void), |
6076 | hook_bool_void_false) | |
6077 | ||
6078 | /* Returns true if the compiler is allowed to try to replace register number | |
6079 | from-reg with register number to-reg. */ | |
6080 | DEFHOOK | |
6081 | (can_eliminate, | |
53680238 | 6082 | "This target hook should return @code{true} if the compiler is allowed to\n\ |
673c2f63 | 6083 | try to replace register number @var{from_reg} with register number\n\ |
53680238 BE |
6084 | @var{to_reg}. This target hook will usually be @code{true}, since most of the\n\ |
6085 | cases preventing register elimination are things that the compiler already\n\ | |
673c2f63 JM |
6086 | knows about.\n\ |
6087 | \n\ | |
6088 | Default return value is @code{true}.", | |
38f8b050 JR |
6089 | bool, (const int from_reg, const int to_reg), |
6090 | hook_bool_const_int_const_int_true) | |
6091 | ||
5efd84c5 NF |
6092 | /* Modify any or all of fixed_regs, call_used_regs, global_regs, |
6093 | reg_names, and reg_class_contents to account of the vagaries of the | |
6094 | target. */ | |
6095 | DEFHOOK | |
6096 | (conditional_register_usage, | |
673c2f63 JM |
6097 | "This hook may conditionally modify five variables\n\ |
6098 | @code{fixed_regs}, @code{call_used_regs}, @code{global_regs},\n\ | |
6099 | @code{reg_names}, and @code{reg_class_contents}, to take into account\n\ | |
6100 | any dependence of these register sets on target flags. The first three\n\ | |
527a3750 | 6101 | of these are of type @code{char []} (interpreted as boolean vectors).\n\ |
673c2f63 JM |
6102 | @code{global_regs} is a @code{const char *[]}, and\n\ |
6103 | @code{reg_class_contents} is a @code{HARD_REG_SET}. Before the macro is\n\ | |
6104 | called, @code{fixed_regs}, @code{call_used_regs},\n\ | |
6105 | @code{reg_class_contents}, and @code{reg_names} have been initialized\n\ | |
6106 | from @code{FIXED_REGISTERS}, @code{CALL_USED_REGISTERS},\n\ | |
6107 | @code{REG_CLASS_CONTENTS}, and @code{REGISTER_NAMES}, respectively.\n\ | |
6108 | @code{global_regs} has been cleared, and any @option{-ffixed-@var{reg}},\n\ | |
6109 | @option{-fcall-used-@var{reg}} and @option{-fcall-saved-@var{reg}}\n\ | |
6110 | command options have been applied.\n\ | |
6111 | \n\ | |
6112 | @cindex disabling certain registers\n\ | |
6113 | @cindex controlling register usage\n\ | |
6114 | If the usage of an entire class of registers depends on the target\n\ | |
6115 | flags, you may indicate this to GCC by using this macro to modify\n\ | |
6116 | @code{fixed_regs} and @code{call_used_regs} to 1 for each of the\n\ | |
b48e9677 RS |
6117 | registers in the classes which should not be used by GCC@. Also make\n\ |
6118 | @code{define_register_constraint}s return @code{NO_REGS} for constraints\n\ | |
6119 | that shouldn't be used.\n\ | |
673c2f63 JM |
6120 | \n\ |
6121 | (However, if this class is not included in @code{GENERAL_REGS} and all\n\ | |
6122 | of the insn patterns whose constraints permit this class are\n\ | |
6123 | controlled by target switches, then GCC will automatically avoid using\n\ | |
6124 | these registers when the target switches are opposed to them.)", | |
5efd84c5 NF |
6125 | void, (void), |
6126 | hook_void_void) | |
6127 | ||
8c1dd970 | 6128 | DEFHOOK |
2c25083e TC |
6129 | (stack_clash_protection_alloca_probe_range, |
6130 | "Some targets have an ABI defined interval for which no probing needs to be done.\n\ | |
4d3907c2 | 6131 | When a probe does need to be done this same interval is used as the probe distance\n\ |
2c25083e TC |
6132 | up when doing stack clash protection for alloca.\n\ |
6133 | On such targets this value can be set to override the default probing up interval.\n\ | |
4d3907c2 ML |
6134 | Define this variable to return nonzero if such a probe range is required or zero otherwise.\n\ |
6135 | Defining this hook also requires your functions which make use of alloca to have at least 8 byes\n\ | |
2c25083e TC |
6136 | of outgoing arguments. If this is not the case the stack will be corrupted.\n\ |
6137 | You need not define this macro if it would always have the value zero.", | |
6138 | HOST_WIDE_INT, (void), | |
6139 | default_stack_clash_protection_alloca_probe_range) | |
8c1dd970 JL |
6140 | |
6141 | ||
38f8b050 JR |
6142 | /* Functions specific to the C family of frontends. */ |
6143 | #undef HOOK_PREFIX | |
6144 | #define HOOK_PREFIX "TARGET_C_" | |
6145 | HOOK_VECTOR (TARGET_C, c) | |
6146 | ||
6147 | /* ??? Documenting this hook requires a GFDL license grant. */ | |
6148 | DEFHOOK_UNDOC | |
6149 | (mode_for_suffix, | |
6150 | "Return machine mode for non-standard constant literal suffix @var{c},\ | |
6151 | or VOIDmode if non-standard suffixes are unsupported.", | |
ef4bddc2 | 6152 | machine_mode, (char c), |
38f8b050 JR |
6153 | default_mode_for_suffix) |
6154 | ||
42e02b20 JG |
6155 | DEFHOOK |
6156 | (excess_precision, | |
4d3907c2 ML |
6157 | "Return a value, with the same meaning as the C99 macro\n\ |
6158 | @code{FLT_EVAL_METHOD} that describes which excess precision should be\n\ | |
6159 | applied. @var{type} is either @code{EXCESS_PRECISION_TYPE_IMPLICIT},\n\ | |
f19a3270 | 6160 | @code{EXCESS_PRECISION_TYPE_FAST},\n\ |
6161 | @code{EXCESS_PRECISION_TYPE_STANDARD}, or\n\ | |
6162 | @code{EXCESS_PRECISION_TYPE_FLOAT16}. For\n\ | |
4d3907c2 ML |
6163 | @code{EXCESS_PRECISION_TYPE_IMPLICIT}, the target should return which\n\ |
6164 | precision and range operations will be implictly evaluated in regardless\n\ | |
6165 | of the excess precision explicitly added. For\n\ | |
f19a3270 | 6166 | @code{EXCESS_PRECISION_TYPE_STANDARD}, \n\ |
6167 | @code{EXCESS_PRECISION_TYPE_FLOAT16}, and\n\ | |
4d3907c2 ML |
6168 | @code{EXCESS_PRECISION_TYPE_FAST}, the target should return the\n\ |
6169 | explicit excess precision that should be added depending on the\n\ | |
6170 | value set for @option{-fexcess-precision=@r{[}standard@r{|}fast@r{]}}.\n\ | |
6171 | Note that unpredictable explicit excess precision does not make sense,\n\ | |
6172 | so a target should never return @code{FLT_EVAL_METHOD_UNPREDICTABLE}\n\ | |
f19a3270 | 6173 | when @var{type} is @code{EXCESS_PRECISION_TYPE_STANDARD},\n\ |
6174 | @code{EXCESS_PRECISION_TYPE_FLOAT16} or\n\ | |
4d3907c2 | 6175 | @code{EXCESS_PRECISION_TYPE_FAST}.", |
42e02b20 JG |
6176 | enum flt_eval_method, (enum excess_precision_type type), |
6177 | default_excess_precision) | |
6178 | ||
38f8b050 JR |
6179 | HOOK_VECTOR_END (c) |
6180 | ||
6181 | /* Functions specific to the C++ frontend. */ | |
6182 | #undef HOOK_PREFIX | |
6183 | #define HOOK_PREFIX "TARGET_CXX_" | |
6184 | HOOK_VECTOR (TARGET_CXX, cxx) | |
6185 | ||
6186 | /* Return the integer type used for guard variables. */ | |
6187 | DEFHOOK | |
6188 | (guard_type, | |
673c2f63 JM |
6189 | "Define this hook to override the integer type used for guard variables.\n\ |
6190 | These are used to implement one-time construction of static objects. The\n\ | |
6191 | default is long_long_integer_type_node.", | |
38f8b050 JR |
6192 | tree, (void), |
6193 | default_cxx_guard_type) | |
6194 | ||
6195 | /* Return true if only the low bit of the guard should be tested. */ | |
6196 | DEFHOOK | |
6197 | (guard_mask_bit, | |
673c2f63 JM |
6198 | "This hook determines how guard variables are used. It should return\n\ |
6199 | @code{false} (the default) if the first byte should be used. A return value of\n\ | |
6200 | @code{true} indicates that only the least significant bit should be used.", | |
38f8b050 JR |
6201 | bool, (void), |
6202 | hook_bool_void_false) | |
6203 | ||
6204 | /* Returns the size of the array cookie for an array of type. */ | |
6205 | DEFHOOK | |
6206 | (get_cookie_size, | |
673c2f63 JM |
6207 | "This hook returns the size of the cookie to use when allocating an array\n\ |
6208 | whose elements have the indicated @var{type}. Assumes that it is already\n\ | |
6209 | known that a cookie is needed. The default is\n\ | |
6210 | @code{max(sizeof (size_t), alignof(type))}, as defined in section 2.7 of the\n\ | |
6211 | IA64/Generic C++ ABI@.", | |
38f8b050 JR |
6212 | tree, (tree type), |
6213 | default_cxx_get_cookie_size) | |
6214 | ||
6215 | /* Returns true if the element size should be stored in the array cookie. */ | |
6216 | DEFHOOK | |
6217 | (cookie_has_size, | |
673c2f63 JM |
6218 | "This hook should return @code{true} if the element size should be stored in\n\ |
6219 | array cookies. The default is to return @code{false}.", | |
38f8b050 JR |
6220 | bool, (void), |
6221 | hook_bool_void_false) | |
6222 | ||
6223 | /* Allows backends to perform additional processing when | |
6224 | deciding if a class should be exported or imported. */ | |
6225 | DEFHOOK | |
6226 | (import_export_class, | |
673c2f63 JM |
6227 | "If defined by a backend this hook allows the decision made to export\n\ |
6228 | class @var{type} to be overruled. Upon entry @var{import_export}\n\ | |
6229 | will contain 1 if the class is going to be exported, @minus{}1 if it is going\n\ | |
6230 | to be imported and 0 otherwise. This function should return the\n\ | |
6231 | modified value and perform any other actions necessary to support the\n\ | |
6232 | backend's targeted operating system.", | |
38f8b050 JR |
6233 | int, (tree type, int import_export), NULL) |
6234 | ||
6235 | /* Returns true if constructors and destructors return "this". */ | |
6236 | DEFHOOK | |
6237 | (cdtor_returns_this, | |
673c2f63 JM |
6238 | "This hook should return @code{true} if constructors and destructors return\n\ |
6239 | the address of the object created/destroyed. The default is to return\n\ | |
6240 | @code{false}.", | |
38f8b050 JR |
6241 | bool, (void), |
6242 | hook_bool_void_false) | |
6243 | ||
6244 | /* Returns true if the key method for a class can be an inline | |
6245 | function, so long as it is not declared inline in the class | |
6246 | itself. Returning true is the behavior required by the Itanium C++ ABI. */ | |
6247 | DEFHOOK | |
6248 | (key_method_may_be_inline, | |
673c2f63 JM |
6249 | "This hook returns true if the key method for a class (i.e., the method\n\ |
6250 | which, if defined in the current translation unit, causes the virtual\n\ | |
6251 | table to be emitted) may be an inline function. Under the standard\n\ | |
6252 | Itanium C++ ABI the key method may be an inline function so long as\n\ | |
6253 | the function is not declared inline in the class definition. Under\n\ | |
6254 | some variants of the ABI, an inline function can never be the key\n\ | |
6255 | method. The default is to return @code{true}.", | |
38f8b050 JR |
6256 | bool, (void), |
6257 | hook_bool_void_true) | |
6258 | ||
6259 | DEFHOOK | |
6260 | (determine_class_data_visibility, | |
4d3907c2 ML |
6261 | "@var{decl} is a virtual table, virtual table table, typeinfo object,\n\ |
6262 | or other similar implicit class data object that will be emitted with\n\ | |
6263 | external linkage in this translation unit. No ELF visibility has been\n\ | |
6264 | explicitly specified. If the target needs to specify a visibility\n\ | |
6265 | other than that of the containing class, use this hook to set\n\ | |
6266 | @code{DECL_VISIBILITY} and @code{DECL_VISIBILITY_SPECIFIED}.", | |
38f8b050 JR |
6267 | void, (tree decl), |
6268 | hook_void_tree) | |
6269 | ||
6270 | /* Returns true (the default) if virtual tables and other | |
6271 | similar implicit class data objects are always COMDAT if they | |
6272 | have external linkage. If this hook returns false, then | |
6273 | class data for classes whose virtual table will be emitted in | |
6274 | only one translation unit will not be COMDAT. */ | |
6275 | DEFHOOK | |
6276 | (class_data_always_comdat, | |
673c2f63 JM |
6277 | "This hook returns true (the default) if virtual tables and other\n\ |
6278 | similar implicit class data objects are always COMDAT if they have\n\ | |
6279 | external linkage. If this hook returns false, then class data for\n\ | |
6280 | classes whose virtual table will be emitted in only one translation\n\ | |
6281 | unit will not be COMDAT.", | |
38f8b050 JR |
6282 | bool, (void), |
6283 | hook_bool_void_true) | |
6284 | ||
6285 | /* Returns true (the default) if the RTTI for the basic types, | |
6286 | which is always defined in the C++ runtime, should be COMDAT; | |
6287 | false if it should not be COMDAT. */ | |
6288 | DEFHOOK | |
6289 | (library_rtti_comdat, | |
673c2f63 JM |
6290 | "This hook returns true (the default) if the RTTI information for\n\ |
6291 | the basic types which is defined in the C++ runtime should always\n\ | |
6292 | be COMDAT, false if it should not be COMDAT.", | |
38f8b050 JR |
6293 | bool, (void), |
6294 | hook_bool_void_true) | |
6295 | ||
6296 | /* Returns true if __aeabi_atexit should be used to register static | |
6297 | destructors. */ | |
6298 | DEFHOOK | |
6299 | (use_aeabi_atexit, | |
673c2f63 JM |
6300 | "This hook returns true if @code{__aeabi_atexit} (as defined by the ARM EABI)\n\ |
6301 | should be used to register static destructors when @option{-fuse-cxa-atexit}\n\ | |
6302 | is in effect. The default is to return false to use @code{__cxa_atexit}.", | |
38f8b050 JR |
6303 | bool, (void), |
6304 | hook_bool_void_false) | |
6305 | ||
6306 | /* Returns true if target may use atexit in the same manner as | |
6307 | __cxa_atexit to register static destructors. */ | |
6308 | DEFHOOK | |
6309 | (use_atexit_for_cxa_atexit, | |
673c2f63 JM |
6310 | "This hook returns true if the target @code{atexit} function can be used\n\ |
6311 | in the same manner as @code{__cxa_atexit} to register C++ static\n\ | |
6312 | destructors. This requires that @code{atexit}-registered functions in\n\ | |
6313 | shared libraries are run in the correct order when the libraries are\n\ | |
6314 | unloaded. The default is to return false.", | |
38f8b050 JR |
6315 | bool, (void), |
6316 | hook_bool_void_false) | |
6317 | ||
6318 | DEFHOOK | |
6319 | (adjust_class_at_definition, | |
4d3907c2 ML |
6320 | "@var{type} is a C++ class (i.e., RECORD_TYPE or UNION_TYPE) that has just\n\ |
6321 | been defined. Use this hook to make adjustments to the class (eg, tweak\n\ | |
6322 | visibility or perform any other required target modifications).", | |
38f8b050 JR |
6323 | void, (tree type), |
6324 | hook_void_tree) | |
6325 | ||
5b880ea6 RO |
6326 | DEFHOOK |
6327 | (decl_mangling_context, | |
6328 | "Return target-specific mangling context of @var{decl} or @code{NULL_TREE}.", | |
6329 | tree, (const_tree decl), | |
6330 | hook_tree_const_tree_null) | |
6331 | ||
38f8b050 JR |
6332 | HOOK_VECTOR_END (cxx) |
6333 | ||
6334 | /* Functions and data for emulated TLS support. */ | |
6335 | #undef HOOK_PREFIX | |
6336 | #define HOOK_PREFIX "TARGET_EMUTLS_" | |
6337 | HOOK_VECTOR (TARGET_EMUTLS, emutls) | |
6338 | ||
6339 | /* Name of the address and common functions. */ | |
6340 | DEFHOOKPOD | |
6341 | (get_address, | |
673c2f63 JM |
6342 | "Contains the name of the helper function that uses a TLS control\n\ |
6343 | object to locate a TLS instance. The default causes libgcc's\n\ | |
6344 | emulated TLS helper function to be used.", | |
38f8b050 JR |
6345 | const char *, "__builtin___emutls_get_address") |
6346 | ||
6347 | DEFHOOKPOD | |
6348 | (register_common, | |
673c2f63 JM |
6349 | "Contains the name of the helper function that should be used at\n\ |
6350 | program startup to register TLS objects that are implicitly\n\ | |
6351 | initialized to zero. If this is @code{NULL}, all TLS objects will\n\ | |
6352 | have explicit initializers. The default causes libgcc's emulated TLS\n\ | |
6353 | registration function to be used.", | |
38f8b050 JR |
6354 | const char *, "__builtin___emutls_register_common") |
6355 | ||
6356 | /* Prefixes for proxy variable and template. */ | |
6357 | DEFHOOKPOD | |
6358 | (var_section, | |
673c2f63 JM |
6359 | "Contains the name of the section in which TLS control variables should\n\ |
6360 | be placed. The default of @code{NULL} allows these to be placed in\n\ | |
6361 | any section.", | |
38f8b050 JR |
6362 | const char *, NULL) |
6363 | ||
6364 | DEFHOOKPOD | |
6365 | (tmpl_section, | |
673c2f63 JM |
6366 | "Contains the name of the section in which TLS initializers should be\n\ |
6367 | placed. The default of @code{NULL} allows these to be placed in any\n\ | |
6368 | section.", | |
38f8b050 JR |
6369 | const char *, NULL) |
6370 | ||
6371 | /* Prefixes for proxy variable and template. */ | |
6372 | DEFHOOKPOD | |
6373 | (var_prefix, | |
673c2f63 JM |
6374 | "Contains the prefix to be prepended to TLS control variable names.\n\ |
6375 | The default of @code{NULL} uses a target-specific prefix.", | |
38f8b050 JR |
6376 | const char *, NULL) |
6377 | ||
6378 | DEFHOOKPOD | |
6379 | (tmpl_prefix, | |
673c2f63 JM |
6380 | "Contains the prefix to be prepended to TLS initializer objects. The\n\ |
6381 | default of @code{NULL} uses a target-specific prefix.", | |
38f8b050 JR |
6382 | const char *, NULL) |
6383 | ||
6384 | /* Function to generate field definitions of the proxy variable. */ | |
6385 | DEFHOOK | |
6386 | (var_fields, | |
673c2f63 JM |
6387 | "Specifies a function that generates the FIELD_DECLs for a TLS control\n\ |
6388 | object type. @var{type} is the RECORD_TYPE the fields are for and\n\ | |
6389 | @var{name} should be filled with the structure tag, if the default of\n\ | |
6390 | @code{__emutls_object} is unsuitable. The default creates a type suitable\n\ | |
6391 | for libgcc's emulated TLS function.", | |
38f8b050 JR |
6392 | tree, (tree type, tree *name), |
6393 | default_emutls_var_fields) | |
6394 | ||
6395 | /* Function to initialize a proxy variable. */ | |
6396 | DEFHOOK | |
6397 | (var_init, | |
673c2f63 JM |
6398 | "Specifies a function that generates the CONSTRUCTOR to initialize a\n\ |
6399 | TLS control object. @var{var} is the TLS control object, @var{decl}\n\ | |
6400 | is the TLS object and @var{tmpl_addr} is the address of the\n\ | |
6401 | initializer. The default initializes libgcc's emulated TLS control object.", | |
38f8b050 JR |
6402 | tree, (tree var, tree decl, tree tmpl_addr), |
6403 | default_emutls_var_init) | |
6404 | ||
6405 | /* Whether we are allowed to alter the usual alignment of the | |
6406 | proxy variable. */ | |
6407 | DEFHOOKPOD | |
6408 | (var_align_fixed, | |
673c2f63 JM |
6409 | "Specifies whether the alignment of TLS control variable objects is\n\ |
6410 | fixed and should not be increased as some backends may do to optimize\n\ | |
6411 | single objects. The default is false.", | |
38f8b050 JR |
6412 | bool, false) |
6413 | ||
6414 | /* Whether we can emit debug information for TLS vars. */ | |
6415 | DEFHOOKPOD | |
6416 | (debug_form_tls_address, | |
673c2f63 JM |
6417 | "Specifies whether a DWARF @code{DW_OP_form_tls_address} location descriptor\n\ |
6418 | may be used to describe emulated TLS control objects.", | |
38f8b050 JR |
6419 | bool, false) |
6420 | ||
6421 | HOOK_VECTOR_END (emutls) | |
6422 | ||
6423 | #undef HOOK_PREFIX | |
6424 | #define HOOK_PREFIX "TARGET_OPTION_" | |
6425 | HOOK_VECTOR (TARGET_OPTION_HOOKS, target_option_hooks) | |
6426 | ||
7aa7f2e3 SL |
6427 | /* Function to validate the attribute((target(...))) strings. If |
6428 | the option is validated, the hook should also fill in | |
6429 | DECL_FUNCTION_SPECIFIC_TARGET in the function decl node. */ | |
38f8b050 JR |
6430 | DEFHOOK |
6431 | (valid_attribute_p, | |
673c2f63 JM |
6432 | "This hook is called to parse @code{attribute(target(\"...\"))}, which\n\ |
6433 | allows setting target-specific options on individual functions.\n\ | |
6434 | These function-specific options may differ\n\ | |
6435 | from the options specified on the command line. The hook should return\n\ | |
6436 | @code{true} if the options are valid.\n\ | |
6437 | \n\ | |
6438 | The hook should set the @code{DECL_FUNCTION_SPECIFIC_TARGET} field in\n\ | |
6439 | the function declaration to hold a pointer to a target-specific\n\ | |
6440 | @code{struct cl_target_option} structure.", | |
38f8b050 JR |
6441 | bool, (tree fndecl, tree name, tree args, int flags), |
6442 | default_target_option_valid_attribute_p) | |
6443 | ||
6444 | /* Function to save any extra target state in the target options structure. */ | |
6445 | DEFHOOK | |
6446 | (save, | |
673c2f63 JM |
6447 | "This hook is called to save any additional target-specific information\n\ |
6448 | in the @code{struct cl_target_option} structure for function-specific\n\ | |
bf7b5747 | 6449 | options from the @code{struct gcc_options} structure.\n\ |
673c2f63 | 6450 | @xref{Option file format}.", |
ba948b37 JJ |
6451 | void, (struct cl_target_option *ptr, struct gcc_options *opts, |
6452 | struct gcc_options *opts_set), NULL) | |
38f8b050 JR |
6453 | |
6454 | /* Function to restore any extra target state from the target options | |
6455 | structure. */ | |
6456 | DEFHOOK | |
6457 | (restore, | |
673c2f63 JM |
6458 | "This hook is called to restore any additional target-specific\n\ |
6459 | information in the @code{struct cl_target_option} structure for\n\ | |
bf7b5747 | 6460 | function-specific options to the @code{struct gcc_options} structure.", |
ba948b37 JJ |
6461 | void, (struct gcc_options *opts, struct gcc_options *opts_set, |
6462 | struct cl_target_option *ptr), NULL) | |
38f8b050 | 6463 | |
59913123 JJ |
6464 | /* Function to update target-specific option information after being |
6465 | streamed in. */ | |
6466 | DEFHOOK | |
6467 | (post_stream_in, | |
6468 | "This hook is called to update target-specific information in the\n\ | |
6469 | @code{struct cl_target_option} structure after it is streamed in from\n\ | |
6470 | LTO bytecode.", | |
6471 | void, (struct cl_target_option *ptr), NULL) | |
6472 | ||
38f8b050 JR |
6473 | /* Function to print any extra target state from the target options |
6474 | structure. */ | |
6475 | DEFHOOK | |
6476 | (print, | |
673c2f63 JM |
6477 | "This hook is called to print any additional target-specific\n\ |
6478 | information in the @code{struct cl_target_option} structure for\n\ | |
6479 | function-specific options.", | |
38f8b050 JR |
6480 | void, (FILE *file, int indent, struct cl_target_option *ptr), NULL) |
6481 | ||
7aa7f2e3 | 6482 | /* Function to parse arguments to be validated for #pragma target, and to |
38f8b050 JR |
6483 | change the state if the options are valid. If the first argument is |
6484 | NULL, the second argument specifies the default options to use. Return | |
6485 | true if the options are valid, and set the current state. */ | |
56cb42ea | 6486 | DEFHOOK |
38f8b050 | 6487 | (pragma_parse, |
673c2f63 JM |
6488 | "This target hook parses the options for @code{#pragma GCC target}, which\n\ |
6489 | sets the target-specific options for functions that occur later in the\n\ | |
6490 | input stream. The options accepted should be the same as those handled by the\n\ | |
6491 | @code{TARGET_OPTION_VALID_ATTRIBUTE_P} hook.", | |
38f8b050 JR |
6492 | bool, (tree args, tree pop_target), |
6493 | default_target_option_pragma_parse) | |
6494 | ||
6495 | /* Do option overrides for the target. */ | |
6496 | DEFHOOK | |
6497 | (override, | |
673c2f63 JM |
6498 | "Sometimes certain combinations of command options do not make sense on\n\ |
6499 | a particular target machine. You can override the hook\n\ | |
6500 | @code{TARGET_OPTION_OVERRIDE} to take account of this. This hooks is called\n\ | |
6501 | once just after all the command options have been parsed.\n\ | |
6502 | \n\ | |
6503 | Don't use this hook to turn on various extra optimizations for\n\ | |
6504 | @option{-O}. That is what @code{TARGET_OPTION_OPTIMIZATION} is for.\n\ | |
6505 | \n\ | |
6506 | If you need to do something whenever the optimization level is\n\ | |
6507 | changed via the optimize attribute or pragma, see\n\ | |
6508 | @code{TARGET_OVERRIDE_OPTIONS_AFTER_CHANGE}", | |
38f8b050 | 6509 | void, (void), |
c5387660 | 6510 | hook_void_void) |
38f8b050 | 6511 | |
3649b9b7 ST |
6512 | /* This function returns true if DECL1 and DECL2 are versions of the same |
6513 | function. DECL1 and DECL2 are function versions if and only if they | |
6514 | have the same function signature and different target specific attributes, | |
6515 | that is, they are compiled for different target machines. */ | |
6516 | DEFHOOK | |
6517 | (function_versions, | |
673c2f63 JM |
6518 | "This target hook returns @code{true} if @var{DECL1} and @var{DECL2} are\n\ |
6519 | versions of the same function. @var{DECL1} and @var{DECL2} are function\n\ | |
6520 | versions if and only if they have the same function signature and\n\ | |
6521 | different target specific attributes, that is, they are compiled for\n\ | |
6522 | different target machines.", | |
3649b9b7 ST |
6523 | bool, (tree decl1, tree decl2), |
6524 | hook_bool_tree_tree_false) | |
6525 | ||
38f8b050 JR |
6526 | /* Function to determine if one function can inline another function. */ |
6527 | #undef HOOK_PREFIX | |
6528 | #define HOOK_PREFIX "TARGET_" | |
6529 | DEFHOOK | |
6530 | (can_inline_p, | |
673c2f63 JM |
6531 | "This target hook returns @code{false} if the @var{caller} function\n\ |
6532 | cannot inline @var{callee}, based on target specific information. By\n\ | |
6533 | default, inlining is not allowed if the callee function has function\n\ | |
6534 | specific target options and the caller does not use the same options.", | |
38f8b050 JR |
6535 | bool, (tree caller, tree callee), |
6536 | default_target_can_inline_p) | |
6537 | ||
0fc60c18 KL |
6538 | DEFHOOK |
6539 | (update_ipa_fn_target_info, | |
6540 | "Allow target to analyze all gimple statements for the given function to\n\ | |
6541 | record and update some target specific information for inlining. A typical\n\ | |
6542 | example is that a caller with one isa feature disabled is normally not\n\ | |
6543 | allowed to inline a callee with that same isa feature enabled even which is\n\ | |
6544 | attributed by always_inline, but with the conservative analysis on all\n\ | |
6545 | statements of the callee if we are able to guarantee the callee does not\n\ | |
6546 | exploit any instructions from the mismatch isa feature, it would be safe to\n\ | |
6547 | allow the caller to inline the callee.\n\ | |
6548 | @var{info} is one @code{unsigned int} value to record information in which\n\ | |
6549 | one set bit indicates one corresponding feature is detected in the analysis,\n\ | |
6550 | @var{stmt} is the statement being analyzed. Return true if target still\n\ | |
6551 | need to analyze the subsequent statements, otherwise return false to stop\n\ | |
6552 | subsequent analysis.\n\ | |
6553 | The default version of this hook returns false.", | |
6554 | bool, (unsigned int& info, const gimple* stmt), | |
6555 | default_update_ipa_fn_target_info) | |
6556 | ||
6557 | DEFHOOK | |
6558 | (need_ipa_fn_target_info, | |
6559 | "Allow target to check early whether it is necessary to analyze all gimple\n\ | |
6560 | statements in the given function to update target specific information for\n\ | |
6561 | inlining. See hook @code{update_ipa_fn_target_info} for usage example of\n\ | |
6562 | target specific information. This hook is expected to be invoked ahead of\n\ | |
6563 | the iterating with hook @code{update_ipa_fn_target_info}.\n\ | |
6564 | @var{decl} is the function being analyzed, @var{info} is the same as what\n\ | |
6565 | in hook @code{update_ipa_fn_target_info}, target can do one time update\n\ | |
6566 | into @var{info} without iterating for some case. Return true if target\n\ | |
6567 | decides to analyze all gimple statements to collect information, otherwise\n\ | |
6568 | return false.\n\ | |
6569 | The default version of this hook returns false.", | |
6570 | bool, (const_tree decl, unsigned int& info), | |
6571 | default_need_ipa_fn_target_info) | |
6572 | ||
63b0cb04 CB |
6573 | DEFHOOK |
6574 | (relayout_function, | |
4d3907c2 ML |
6575 | "This target hook fixes function @var{fndecl} after attributes are processed.\n\ |
6576 | Default does nothing. On ARM, the default function's alignment is updated\n\ | |
6577 | with the attribute target.", | |
63b0cb04 CB |
6578 | void, (tree fndecl), |
6579 | hook_void_tree) | |
6580 | ||
38f8b050 JR |
6581 | HOOK_VECTOR_END (target_option) |
6582 | ||
6583 | /* For targets that need to mark extra registers as live on entry to | |
6584 | the function, they should define this target hook and set their | |
6585 | bits in the bitmap passed in. */ | |
6586 | DEFHOOK | |
6587 | (extra_live_on_entry, | |
673c2f63 JM |
6588 | "Add any hard registers to @var{regs} that are live on entry to the\n\ |
6589 | function. This hook only needs to be defined to provide registers that\n\ | |
6590 | cannot be found by examination of FUNCTION_ARG_REGNO_P, the callee saved\n\ | |
6591 | registers, STATIC_CHAIN_INCOMING_REGNUM, STATIC_CHAIN_REGNUM,\n\ | |
6592 | TARGET_STRUCT_VALUE_RTX, FRAME_POINTER_REGNUM, EH_USES,\n\ | |
6593 | FRAME_POINTER_REGNUM, ARG_POINTER_REGNUM, and the PIC_OFFSET_TABLE_REGNUM.", | |
38f8b050 JR |
6594 | void, (bitmap regs), |
6595 | hook_void_bitmap) | |
6596 | ||
aaeaa9a9 | 6597 | /* Targets should define this target hook to mark that non-callee clobbers are |
73b3e61b TV |
6598 | present in CALL_INSN_FUNCTION_USAGE for all the calls that bind to a local |
6599 | definition. */ | |
aaeaa9a9 RO |
6600 | DEFHOOKPOD |
6601 | (call_fusage_contains_non_callee_clobbers, | |
73b3e61b TV |
6602 | "Set to true if each call that binds to a local definition explicitly\n\ |
6603 | clobbers or sets all non-fixed registers modified by performing the call.\n\ | |
6604 | That is, by the call pattern itself, or by code that might be inserted by the\n\ | |
630ba2fd | 6605 | linker (e.g.@: stubs, veneers, branch islands), but not including those\n\ |
73b3e61b TV |
6606 | modifiable by the callee. The affected registers may be mentioned explicitly\n\ |
6607 | in the call pattern, or included as clobbers in CALL_INSN_FUNCTION_USAGE.\n\ | |
6608 | The default version of this hook is set to false. The purpose of this hook\n\ | |
1e288103 | 6609 | is to enable the fipa-ra optimization.", |
aaeaa9a9 RO |
6610 | bool, |
6611 | false) | |
6612 | ||
ee3d2ecd JJ |
6613 | /* Fill in additional registers set up by prologue into a regset. */ |
6614 | DEFHOOK | |
6615 | (set_up_by_prologue, | |
4d3907c2 ML |
6616 | "This hook should add additional registers that are computed by the prologue\n\ |
6617 | to the hard regset for shrink-wrapping optimization purposes.", | |
ee3d2ecd JJ |
6618 | void, (struct hard_reg_set_container *), |
6619 | NULL) | |
6620 | ||
d45eae79 SL |
6621 | /* For targets that have attributes that can affect whether a |
6622 | function's return statements need checking. For instance a 'naked' | |
6623 | function attribute. */ | |
6624 | DEFHOOK | |
6625 | (warn_func_return, | |
4d3907c2 ML |
6626 | "True if a function's return statements should be checked for matching\n\ |
6627 | the function's return type. This includes checking for falling off the end\n\ | |
6628 | of a non-void function. Return false if no such check should be made.", | |
d45eae79 SL |
6629 | bool, (tree), |
6630 | hook_bool_tree_true) | |
6631 | ||
20a6ece0 SB |
6632 | #undef HOOK_PREFIX |
6633 | #define HOOK_PREFIX "TARGET_SHRINK_WRAP_" | |
6634 | HOOK_VECTOR (TARGET_SHRINK_WRAP_HOOKS, shrink_wrap) | |
6635 | ||
6636 | DEFHOOK | |
6637 | (get_separate_components, | |
6638 | "This hook should return an @code{sbitmap} with the bits set for those\n\ | |
6639 | components that can be separately shrink-wrapped in the current function.\n\ | |
6640 | Return @code{NULL} if the current function should not get any separate\n\ | |
6641 | shrink-wrapping.\n\ | |
6642 | Don't define this hook if it would always return @code{NULL}.\n\ | |
6643 | If it is defined, the other hooks in this group have to be defined as well.", | |
6644 | sbitmap, (void), | |
6645 | NULL) | |
6646 | ||
6647 | DEFHOOK | |
6648 | (components_for_bb, | |
6649 | "This hook should return an @code{sbitmap} with the bits set for those\n\ | |
6650 | components where either the prologue component has to be executed before\n\ | |
6651 | the @code{basic_block}, or the epilogue component after it, or both.", | |
6652 | sbitmap, (basic_block), | |
6653 | NULL) | |
6654 | ||
6655 | DEFHOOK | |
6656 | (disqualify_components, | |
6657 | "This hook should clear the bits in the @var{components} bitmap for those\n\ | |
6658 | components in @var{edge_components} that the target cannot handle on edge\n\ | |
6659 | @var{e}, where @var{is_prologue} says if this is for a prologue or an\n\ | |
6660 | epilogue instead.", | |
6661 | void, (sbitmap components, edge e, sbitmap edge_components, bool is_prologue), | |
6662 | NULL) | |
6663 | ||
6664 | DEFHOOK | |
6665 | (emit_prologue_components, | |
6666 | "Emit prologue insns for the components indicated by the parameter.", | |
6667 | void, (sbitmap), | |
6668 | NULL) | |
6669 | ||
6670 | DEFHOOK | |
6671 | (emit_epilogue_components, | |
6672 | "Emit epilogue insns for the components indicated by the parameter.", | |
6673 | void, (sbitmap), | |
6674 | NULL) | |
6675 | ||
6676 | DEFHOOK | |
6677 | (set_handled_components, | |
6678 | "Mark the components in the parameter as handled, so that the\n\ | |
6679 | @code{prologue} and @code{epilogue} named patterns know to ignore those\n\ | |
6680 | components. The target code should not hang on to the @code{sbitmap}, it\n\ | |
6681 | will be deleted after this call.", | |
6682 | void, (sbitmap), | |
6683 | NULL) | |
6684 | ||
6685 | HOOK_VECTOR_END (shrink_wrap) | |
6686 | #undef HOOK_PREFIX | |
6687 | #define HOOK_PREFIX "TARGET_" | |
6688 | ||
f0a0390e RH |
6689 | /* Determine the type of unwind info to emit for debugging. */ |
6690 | DEFHOOK | |
6691 | (debug_unwind_info, | |
673c2f63 JM |
6692 | "This hook defines the mechanism that will be used for describing frame\n\ |
6693 | unwind information to the debugger. Normally the hook will return\n\ | |
6694 | @code{UI_DWARF2} if DWARF 2 debug information is enabled, and\n\ | |
6695 | return @code{UI_NONE} otherwise.\n\ | |
6696 | \n\ | |
6697 | A target may return @code{UI_DWARF2} even when DWARF 2 debug information\n\ | |
6698 | is disabled in order to always output DWARF 2 frame information.\n\ | |
6699 | \n\ | |
6700 | A target may return @code{UI_TARGET} if it has ABI specified unwind tables.\n\ | |
6701 | This will suppress generation of the normal debug frame unwind information.", | |
f0a0390e RH |
6702 | enum unwind_info_type, (void), |
6703 | default_debug_unwind_info) | |
6704 | ||
924c9e3e | 6705 | DEFHOOK |
4d3907c2 ML |
6706 | (reset_location_view, |
6707 | "This hook, if defined, enables -ginternal-reset-location-views, and\n\ | |
924c9e3e AO |
6708 | uses its result to override cases in which the estimated min insn\n\ |
6709 | length might be nonzero even when a PC advance (i.e., a view reset)\n\ | |
6710 | cannot be taken for granted.\n\ | |
6711 | \n\ | |
6712 | If the hook is defined, it must return a positive value to indicate\n\ | |
6713 | the insn definitely advances the PC, and so the view number can be\n\ | |
6714 | safely assumed to be reset; a negative value to mean the insn\n\ | |
6715 | definitely does not advance the PC, and os the view number must not\n\ | |
6716 | be reset; or zero to decide based on the estimated insn length.\n\ | |
6717 | \n\ | |
6718 | If insn length is to be regarded as reliable, set the hook to\n\ | |
6719 | @code{hook_int_rtx_insn_0}.", | |
6720 | int, (rtx_insn *), NULL) | |
6721 | ||
c354951b AK |
6722 | /* The code parameter should be of type enum rtx_code but this is not |
6723 | defined at this time. */ | |
6724 | DEFHOOK | |
6725 | (canonicalize_comparison, | |
673c2f63 JM |
6726 | "On some machines not all possible comparisons are defined, but you can\n\ |
6727 | convert an invalid comparison into a valid one. For example, the Alpha\n\ | |
6728 | does not have a @code{GT} comparison, but you can use an @code{LT}\n\ | |
6729 | comparison instead and swap the order of the operands.\n\ | |
6730 | \n\ | |
6731 | On such machines, implement this hook to do any required conversions.\n\ | |
6732 | @var{code} is the initial comparison code and @var{op0} and @var{op1}\n\ | |
6733 | are the left and right operands of the comparison, respectively. If\n\ | |
6734 | @var{op0_preserve_value} is @code{true} the implementation is not\n\ | |
6735 | allowed to change the value of @var{op0} since the value might be used\n\ | |
6736 | in RTXs which aren't comparisons. E.g. the implementation is not\n\ | |
6737 | allowed to swap operands in that case.\n\ | |
6738 | \n\ | |
6739 | GCC will not assume that the comparison resulting from this macro is\n\ | |
6740 | valid but will see if the resulting insn matches a pattern in the\n\ | |
6741 | @file{md} file.\n\ | |
6742 | \n\ | |
6743 | You need not to implement this hook if it would never change the\n\ | |
6744 | comparison code or operands.", | |
c354951b AK |
6745 | void, (int *code, rtx *op0, rtx *op1, bool op0_preserve_value), |
6746 | default_canonicalize_comparison) | |
6747 | ||
894d8b41 EB |
6748 | DEFHOOK |
6749 | (min_arithmetic_precision, | |
6750 | "On some RISC architectures with 64-bit registers, the processor also\n\ | |
6751 | maintains 32-bit condition codes that make it possible to do real 32-bit\n\ | |
6752 | arithmetic, although the operations are performed on the full registers.\n\ | |
6753 | \n\ | |
6754 | On such architectures, defining this hook to 32 tells the compiler to try\n\ | |
6755 | using 32-bit arithmetical operations setting the condition codes instead\n\ | |
6756 | of doing full 64-bit arithmetic.\n\ | |
6757 | \n\ | |
6758 | More generally, define this hook on RISC architectures if you want the\n\ | |
6759 | compiler to try using arithmetical operations setting the condition codes\n\ | |
6760 | with a precision lower than the word precision.\n\ | |
6761 | \n\ | |
6762 | You need not define this hook if @code{WORD_REGISTER_OPERATIONS} is not\n\ | |
6763 | defined to 1.", | |
6764 | unsigned int, (void), default_min_arithmetic_precision) | |
6765 | ||
57c5ab1b RH |
6766 | DEFHOOKPOD |
6767 | (atomic_test_and_set_trueval, | |
4d3907c2 ML |
6768 | "This value should be set if the result written by\n\ |
6769 | @code{atomic_test_and_set} is not exactly 1, i.e.@: the\n\ | |
6770 | @code{bool} @code{true}.", | |
57c5ab1b | 6771 | unsigned char, 1) |
267bac10 | 6772 | |
fceec4d3 AM |
6773 | /* Return an unsigned int representing the alignment (in bits) of the atomic |
6774 | type which maps to machine MODE. This allows alignment to be overridden | |
6775 | as needed. */ | |
6776 | DEFHOOK | |
6777 | (atomic_align_for_mode, | |
4d3907c2 ML |
6778 | "If defined, this function returns an appropriate alignment in bits for an\n\ |
6779 | atomic object of machine_mode @var{mode}. If 0 is returned then the\n\ | |
6780 | default alignment for the specified mode is used.", | |
ef4bddc2 | 6781 | unsigned int, (machine_mode mode), |
fceec4d3 AM |
6782 | hook_uint_mode_0) |
6783 | ||
267bac10 JM |
6784 | DEFHOOK |
6785 | (atomic_assign_expand_fenv, | |
4d3907c2 ML |
6786 | "ISO C11 requires atomic compound assignments that may raise floating-point\n\ |
6787 | exceptions to raise exceptions corresponding to the arithmetic operation\n\ | |
6788 | whose result was successfully stored in a compare-and-exchange sequence.\n\ | |
6789 | This requires code equivalent to calls to @code{feholdexcept},\n\ | |
6790 | @code{feclearexcept} and @code{feupdateenv} to be generated at\n\ | |
6791 | appropriate points in the compare-and-exchange sequence. This hook should\n\ | |
6792 | set @code{*@var{hold}} to an expression equivalent to the call to\n\ | |
6793 | @code{feholdexcept}, @code{*@var{clear}} to an expression equivalent to\n\ | |
6794 | the call to @code{feclearexcept} and @code{*@var{update}} to an expression\n\ | |
6795 | equivalent to the call to @code{feupdateenv}. The three expressions are\n\ | |
6796 | @code{NULL_TREE} on entry to the hook and may be left as @code{NULL_TREE}\n\ | |
6797 | if no code is required in a particular place. The default implementation\n\ | |
6798 | leaves all three expressions as @code{NULL_TREE}. The\n\ | |
6799 | @code{__atomic_feraiseexcept} function from @code{libatomic} may be of use\n\ | |
6800 | as part of the code generated in @code{*@var{update}}.", | |
267bac10 JM |
6801 | void, (tree *hold, tree *clear, tree *update), |
6802 | default_atomic_assign_expand_fenv) | |
6803 | ||
38f8b050 JR |
6804 | /* Leave the boolean fields at the end. */ |
6805 | ||
38f8b050 JR |
6806 | /* True if we can create zeroed data by switching to a BSS section |
6807 | and then using ASM_OUTPUT_SKIP to allocate the space. */ | |
6808 | DEFHOOKPOD | |
6809 | (have_switchable_bss_sections, | |
673c2f63 JM |
6810 | "This flag is true if we can create zeroed data by switching to a BSS\n\ |
6811 | section and then using @code{ASM_OUTPUT_SKIP} to allocate the space.\n\ | |
6812 | This is true on most ELF targets.", | |
38f8b050 JR |
6813 | bool, false) |
6814 | ||
6815 | /* True if "native" constructors and destructors are supported, | |
6816 | false if we're using collect2 for the job. */ | |
6817 | DEFHOOKPOD | |
6818 | (have_ctors_dtors, | |
673c2f63 JM |
6819 | "This value is true if the target supports some ``native'' method of\n\ |
6820 | collecting constructors and destructors to be run at startup and exit.\n\ | |
6821 | It is false if we must use @command{collect2}.", | |
38f8b050 JR |
6822 | bool, false) |
6823 | ||
fabe8cc4 IS |
6824 | /* True if the target wants DTORs to be run from cxa_atexit. */ |
6825 | DEFHOOKPOD | |
6826 | (dtors_from_cxa_atexit, | |
6827 | "This value is true if the target wants destructors to be queued to be\n\ | |
6828 | run from __cxa_atexit. If this is the case then, for each priority level,\n\ | |
6829 | a new constructor will be entered that registers the destructors for that\n\ | |
6830 | level with __cxa_atexit (and there will be no destructors emitted).\n\ | |
6831 | It is false the method implied by @code{have_ctors_dtors} is used.", | |
6832 | bool, false) | |
6833 | ||
38f8b050 JR |
6834 | /* True if thread-local storage is supported. */ |
6835 | DEFHOOKPOD | |
6836 | (have_tls, | |
673c2f63 JM |
6837 | "Contains the value true if the target supports thread-local storage.\n\ |
6838 | The default value is false.", | |
38f8b050 JR |
6839 | bool, false) |
6840 | ||
6841 | /* True if a small readonly data section is supported. */ | |
6842 | DEFHOOKPOD | |
6843 | (have_srodata_section, | |
673c2f63 JM |
6844 | "Contains the value true if the target places read-only\n\ |
6845 | ``small data'' into a separate section. The default value is false.", | |
38f8b050 JR |
6846 | bool, false) |
6847 | ||
6848 | /* True if EH frame info sections should be zero-terminated. */ | |
6849 | DEFHOOKPOD | |
6850 | (terminate_dw2_eh_frame_info, | |
673c2f63 JM |
6851 | "Contains the value true if the target should add a zero word onto the\n\ |
6852 | end of a Dwarf-2 frame info section when used for exception handling.\n\ | |
6853 | Default value is false if @code{EH_FRAME_SECTION_NAME} is defined, and\n\ | |
6854 | true otherwise.", | |
38f8b050 JR |
6855 | bool, true) |
6856 | ||
6857 | /* True if #NO_APP should be emitted at the beginning of assembly output. */ | |
6858 | DEFHOOKPOD | |
6859 | (asm_file_start_app_off, | |
673c2f63 JM |
6860 | "If this flag is true, the text of the macro @code{ASM_APP_OFF} will be\n\ |
6861 | printed as the very first line in the assembly file, unless\n\ | |
6862 | @option{-fverbose-asm} is in effect. (If that macro has been defined\n\ | |
6863 | to the empty string, this variable has no effect.) With the normal\n\ | |
6864 | definition of @code{ASM_APP_OFF}, the effect is to notify the GNU\n\ | |
6865 | assembler that it need not bother stripping comments or extra\n\ | |
6866 | whitespace from its input. This allows it to work a bit faster.\n\ | |
6867 | \n\ | |
6868 | The default is false. You should not set it to true unless you have\n\ | |
6869 | verified that your port does not generate any extra whitespace or\n\ | |
6870 | comments that will cause GAS to issue errors in NO_APP mode.", | |
38f8b050 JR |
6871 | bool, false) |
6872 | ||
6873 | /* True if output_file_directive should be called for main_input_filename | |
6874 | at the beginning of assembly output. */ | |
6875 | DEFHOOKPOD | |
6876 | (asm_file_start_file_directive, | |
673c2f63 JM |
6877 | "If this flag is true, @code{output_file_directive} will be called\n\ |
6878 | for the primary source file, immediately after printing\n\ | |
6879 | @code{ASM_APP_OFF} (if that is enabled). Most ELF assemblers expect\n\ | |
6880 | this to be done. The default is false.", | |
38f8b050 | 6881 | bool, false) |
38f8b050 JR |
6882 | |
6883 | /* Returns true if we should generate exception tables for use with the | |
6884 | ARM EABI. The effects the encoding of function exception specifications. */ | |
6885 | DEFHOOKPOD | |
6886 | (arm_eabi_unwinder, | |
673c2f63 JM |
6887 | "This flag should be set to @code{true} on targets that use an ARM EABI\n\ |
6888 | based unwinding library, and @code{false} on other targets. This effects\n\ | |
6889 | the format of unwinding tables, and how the unwinder in entered after\n\ | |
6890 | running a cleanup. The default is @code{false}.", | |
38f8b050 JR |
6891 | bool, false) |
6892 | ||
9730bc27 TT |
6893 | DEFHOOKPOD |
6894 | (want_debug_pub_sections, | |
4d3907c2 ML |
6895 | "True if the @code{.debug_pubtypes} and @code{.debug_pubnames} sections\n\ |
6896 | should be emitted. These sections are not used on most platforms, and\n\ | |
6897 | in particular GDB does not use them.", | |
9730bc27 TT |
6898 | bool, false) |
6899 | ||
2ba42841 | 6900 | DEFHOOKPOD |
4d3907c2 ML |
6901 | (delay_sched2, |
6902 | "True if sched2 is not to be run at its normal place.\n\ | |
2ba42841 AO |
6903 | This usually means it will be run as part of machine-specific reorg.", |
6904 | bool, false) | |
6905 | ||
6906 | DEFHOOKPOD | |
4d3907c2 ML |
6907 | (delay_vartrack, |
6908 | "True if vartrack is not to be run at its normal place.\n\ | |
2ba42841 AO |
6909 | This usually means it will be run as part of machine-specific reorg.", |
6910 | bool, false) | |
6911 | ||
a50fa76a | 6912 | DEFHOOKPOD |
4d3907c2 ML |
6913 | (no_register_allocation, |
6914 | "True if register allocation and the passes\n\ | |
a50fa76a BS |
6915 | following it should not be run. Usually true only for virtual assembler\n\ |
6916 | targets.", | |
6917 | bool, false) | |
6918 | ||
38f8b050 JR |
6919 | /* Leave the boolean fields at the end. */ |
6920 | ||
06b90602 CB |
6921 | /* Functions related to mode switching. */ |
6922 | #undef HOOK_PREFIX | |
6923 | #define HOOK_PREFIX "TARGET_MODE_" | |
6924 | HOOK_VECTOR (TARGET_TOGGLE_, mode_switching) | |
6925 | ||
6926 | DEFHOOK | |
6927 | (emit, | |
4d3907c2 ML |
6928 | "Generate one or more insns to set @var{entity} to @var{mode}.\n\ |
6929 | @var{hard_reg_live} is the set of hard registers live at the point where\n\ | |
6930 | the insn(s) are to be inserted. @var{prev_moxde} indicates the mode\n\ | |
6931 | to switch from. Sets of a lower numbered entity will be emitted before\n\ | |
6932 | sets of a higher numbered entity to a mode of the same or lower priority.", | |
cbb1e3d9 | 6933 | void, (int entity, int mode, int prev_mode, HARD_REG_SET regs_live), NULL) |
06b90602 CB |
6934 | |
6935 | DEFHOOK | |
6936 | (needed, | |
4d3907c2 ML |
6937 | "@var{entity} is an integer specifying a mode-switched entity.\n\ |
6938 | If @code{OPTIMIZE_MODE_SWITCHING} is defined, you must define this macro\n\ | |
6939 | to return an integer value not larger than the corresponding element\n\ | |
6940 | in @code{NUM_MODES_FOR_MODE_SWITCHING}, to denote the mode that @var{entity}\n\ | |
6941 | must be switched into prior to the execution of @var{insn}.", | |
ac44248e | 6942 | int, (int entity, rtx_insn *insn), NULL) |
06b90602 CB |
6943 | |
6944 | DEFHOOK | |
6945 | (after, | |
4d3907c2 ML |
6946 | "@var{entity} is an integer specifying a mode-switched entity.\n\ |
6947 | If this macro is defined, it is evaluated for every @var{insn} during mode\n\ | |
6948 | switching. It determines the mode that an insn results\n\ | |
6949 | in (if different from the incoming mode).", | |
ac44248e | 6950 | int, (int entity, int mode, rtx_insn *insn), NULL) |
06b90602 CB |
6951 | |
6952 | DEFHOOK | |
6953 | (entry, | |
4d3907c2 ML |
6954 | "If this macro is defined, it is evaluated for every @var{entity} that\n\ |
6955 | needs mode switching. It should evaluate to an integer, which is a mode\n\ | |
6956 | that @var{entity} is assumed to be switched to at function entry.\n\ | |
6957 | If @code{TARGET_MODE_ENTRY} is defined then @code{TARGET_MODE_EXIT}\n\ | |
6958 | must be defined.", | |
06b90602 CB |
6959 | int, (int entity), NULL) |
6960 | ||
6961 | DEFHOOK | |
6962 | (exit, | |
4d3907c2 ML |
6963 | "If this macro is defined, it is evaluated for every @var{entity} that\n\ |
6964 | needs mode switching. It should evaluate to an integer, which is a mode\n\ | |
6965 | that @var{entity} is assumed to be switched to at function exit.\n\ | |
6966 | If @code{TARGET_MODE_EXIT} is defined then @code{TARGET_MODE_ENTRY}\n\ | |
6967 | must be defined.", | |
06b90602 CB |
6968 | int, (int entity), NULL) |
6969 | ||
6970 | DEFHOOK | |
6971 | (priority, | |
4d3907c2 ML |
6972 | "This macro specifies the order in which modes for @var{entity}\n\ |
6973 | are processed. 0 is the highest priority,\n\ | |
6974 | @code{NUM_MODES_FOR_MODE_SWITCHING[@var{entity}] - 1} the lowest.\n\ | |
6975 | The value of the macro should be an integer designating a mode\n\ | |
6976 | for @var{entity}. For any fixed @var{entity}, @code{mode_priority}\n\ | |
6977 | (@var{entity}, @var{n}) shall be a bijection in 0 @dots{}\n\ | |
6978 | @code{num_modes_for_mode_switching[@var{entity}] - 1}.", | |
06b90602 CB |
6979 | int, (int entity, int n), NULL) |
6980 | ||
6981 | HOOK_VECTOR_END (mode_switching) | |
6982 | ||
3bd87832 MM |
6983 | #undef HOOK_PREFIX |
6984 | #define HOOK_PREFIX "TARGET_MEMTAG_" | |
6985 | HOOK_VECTOR (TARGET_MEMTAG_, memtag) | |
6986 | ||
6987 | DEFHOOK | |
6988 | (can_tag_addresses, | |
6989 | "True if the backend architecture naturally supports ignoring some region\n\ | |
6990 | of pointers. This feature means that @option{-fsanitize=hwaddress} can\n\ | |
6991 | work.\n\ | |
6992 | \n\ | |
6993 | At preset, this feature does not support address spaces. It also requires\n\ | |
6994 | @code{Pmode} to be the same as @code{ptr_mode}.", | |
6995 | bool, (), default_memtag_can_tag_addresses) | |
6996 | ||
0854b584 MM |
6997 | DEFHOOK |
6998 | (tag_size, | |
6999 | "Return the size of a tag (in bits) for this platform.\n\ | |
7000 | \n\ | |
7001 | The default returns 8.", | |
7002 | uint8_t, (), default_memtag_tag_size) | |
7003 | ||
7004 | DEFHOOK | |
7005 | (granule_size, | |
7006 | "Return the size in real memory that each byte in shadow memory refers to.\n\ | |
7007 | I.e. if a variable is @var{X} bytes long in memory, then this hook should\n\ | |
7008 | return the value @var{Y} such that the tag in shadow memory spans\n\ | |
7009 | @var{X}/@var{Y} bytes.\n\ | |
7010 | \n\ | |
7011 | Most variables will need to be aligned to this amount since two variables\n\ | |
7012 | that are neighbors in memory and share a tag granule would need to share\n\ | |
7013 | the same tag.\n\ | |
7014 | \n\ | |
7015 | The default returns 16.", | |
7016 | uint8_t, (), default_memtag_granule_size) | |
7017 | ||
7018 | DEFHOOK | |
7019 | (insert_random_tag, | |
7020 | "Return an RTX representing the value of @var{untagged} but with a\n\ | |
7021 | (possibly) random tag in it.\n\ | |
7022 | Put that value into @var{target} if it is convenient to do so.\n\ | |
7023 | This function is used to generate a tagged base for the current stack frame.", | |
7024 | rtx, (rtx untagged, rtx target), default_memtag_insert_random_tag) | |
7025 | ||
7026 | DEFHOOK | |
7027 | (add_tag, | |
7028 | "Return an RTX that represents the result of adding @var{addr_offset} to\n\ | |
7029 | the address in pointer @var{base} and @var{tag_offset} to the tag in pointer\n\ | |
7030 | @var{base}.\n\ | |
7031 | The resulting RTX must either be a valid memory address or be able to get\n\ | |
7032 | put into an operand with @code{force_operand}.\n\ | |
7033 | \n\ | |
7034 | Unlike other memtag hooks, this must return an expression and not emit any\n\ | |
7035 | RTL.", | |
7036 | rtx, (rtx base, poly_int64 addr_offset, uint8_t tag_offset), | |
7037 | default_memtag_add_tag) | |
7038 | ||
7039 | DEFHOOK | |
7040 | (set_tag, | |
7041 | "Return an RTX representing @var{untagged_base} but with the tag @var{tag}.\n\ | |
7042 | Try and store this in @var{target} if convenient.\n\ | |
7043 | @var{untagged_base} is required to have a zero tag when this hook is called.\n\ | |
7044 | The default of this hook is to set the top byte of @var{untagged_base} to\n\ | |
7045 | @var{tag}.", | |
7046 | rtx, (rtx untagged_base, rtx tag, rtx target), default_memtag_set_tag) | |
7047 | ||
7048 | DEFHOOK | |
7049 | (extract_tag, | |
7050 | "Return an RTX representing the tag stored in @var{tagged_pointer}.\n\ | |
7051 | Store the result in @var{target} if it is convenient.\n\ | |
7052 | The default represents the top byte of the original pointer.", | |
7053 | rtx, (rtx tagged_pointer, rtx target), default_memtag_extract_tag) | |
7054 | ||
7055 | DEFHOOK | |
7056 | (untagged_pointer, | |
7057 | "Return an RTX representing @var{tagged_pointer} with its tag set to zero.\n\ | |
7058 | Store the result in @var{target} if convenient.\n\ | |
7059 | The default clears the top byte of the original pointer.", | |
7060 | rtx, (rtx tagged_pointer, rtx target), default_memtag_untagged_pointer) | |
7061 | ||
3bd87832 | 7062 | HOOK_VECTOR_END (memtag) |
4bccb39e RS |
7063 | #undef HOOK_PREFIX |
7064 | #define HOOK_PREFIX "TARGET_" | |
7065 | ||
7066 | #define DEF_TARGET_INSN(NAME, PROTO) \ | |
7067 | DEFHOOK_UNDOC (have_##NAME, "", bool, (void), false) | |
7068 | #include "target-insns.def" | |
7069 | #undef DEF_TARGET_INSN | |
7070 | ||
7071 | #define DEF_TARGET_INSN(NAME, PROTO) \ | |
7072 | DEFHOOK_UNDOC (gen_##NAME, "", rtx_insn *, PROTO, NULL) | |
7073 | #include "target-insns.def" | |
7074 | #undef DEF_TARGET_INSN | |
7075 | ||
8684d89d RS |
7076 | #define DEF_TARGET_INSN(NAME, PROTO) \ |
7077 | DEFHOOKPOD (code_for_##NAME, "*", enum insn_code, CODE_FOR_nothing) | |
7078 | #include "target-insns.def" | |
7079 | #undef DEF_TARGET_INSN | |
7080 | ||
40af5894 DM |
7081 | DEFHOOK |
7082 | (run_target_selftests, | |
7083 | "If selftests are enabled, run any selftests for this target.", | |
7084 | void, (void), | |
7085 | NULL) | |
7086 | ||
8cdcea51 SH |
7087 | DEFHOOK |
7088 | (gcov_type_size, | |
7089 | "Returns the gcov type size in bits. This type is used for example for\n\ | |
7090 | counters incremented by profiling and code-coverage events. The default\n\ | |
7091 | value is 64, if the type size of long long is greater than 32, otherwise the\n\ | |
7092 | default value is 32. A 64-bit type is recommended to avoid overflows of the\n\ | |
7093 | counters. If the @option{-fprofile-update=atomic} is used, then the\n\ | |
7094 | counters are incremented using atomic operations. Targets not supporting\n\ | |
7095 | 64-bit atomic operations may override the default value and request a 32-bit\n\ | |
7096 | type.", | |
7097 | HOST_WIDE_INT, (void), default_gcov_type_size) | |
7098 | ||
38f8b050 JR |
7099 | /* Close the 'struct gcc_target' definition. */ |
7100 | HOOK_VECTOR_END (C90_EMPTY_HACK) | |
06b90602 | 7101 |