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bccafa26 | 1 | /* Expands front end tree to back end RTL for GCC |
b86e0f5c | 2 | Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, |
cde8f1c8 | 3 | 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 |
3bb6785a | 4 | Free Software Foundation, Inc. |
9dfbe515 | 5 | |
f12b58b3 | 6 | This file is part of GCC. |
9dfbe515 | 7 | |
f12b58b3 | 8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 10 | Software Foundation; either version 3, or (at your option) any later |
f12b58b3 | 11 | version. |
9dfbe515 | 12 | |
f12b58b3 | 13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
9dfbe515 | 17 | |
18 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
9dfbe515 | 21 | |
9dfbe515 | 22 | /* This file handles the generation of rtl code from tree structure |
23 | above the level of expressions, using subroutines in exp*.c and emit-rtl.c. | |
9dfbe515 | 24 | The functions whose names start with `expand_' are called by the |
fcb807f8 | 25 | expander to generate RTL instructions for various kinds of constructs. */ |
9dfbe515 | 26 | |
27 | #include "config.h" | |
405711de | 28 | #include "system.h" |
805e22b2 | 29 | #include "coretypes.h" |
30 | #include "tm.h" | |
3ef9782d | 31 | |
9dfbe515 | 32 | #include "rtl.h" |
64d5fb6a | 33 | #include "hard-reg-set.h" |
9dfbe515 | 34 | #include "tree.h" |
7953c610 | 35 | #include "tm_p.h" |
9dfbe515 | 36 | #include "flags.h" |
485aaaaf | 37 | #include "except.h" |
9dfbe515 | 38 | #include "function.h" |
9dfbe515 | 39 | #include "insn-config.h" |
9dfbe515 | 40 | #include "expr.h" |
d8fc4d0b | 41 | #include "libfuncs.h" |
9dfbe515 | 42 | #include "recog.h" |
649d8da6 | 43 | #include "machmode.h" |
12874aaf | 44 | #include "toplev.h" |
cd03a192 | 45 | #include "output.h" |
a7b0c170 | 46 | #include "ggc.h" |
20325f61 | 47 | #include "langhooks.h" |
cd0fe062 | 48 | #include "predict.h" |
315e4c10 | 49 | #include "optabs.h" |
45550790 | 50 | #include "target.h" |
67d6c12b | 51 | #include "regs.h" |
4527a0e8 | 52 | #include "alloc-pool.h" |
abd3e6b5 | 53 | #include "pretty-print.h" |
9dfbe515 | 54 | \f |
55 | /* Functions and data structures for expanding case statements. */ | |
56 | ||
57 | /* Case label structure, used to hold info on labels within case | |
58 | statements. We handle "range" labels; for a single-value label | |
59 | as in C, the high and low limits are the same. | |
60 | ||
2ca392fd | 61 | We start with a vector of case nodes sorted in ascending order, and |
62 | the default label as the last element in the vector. Before expanding | |
63 | to RTL, we transform this vector into a list linked via the RIGHT | |
64 | fields in the case_node struct. Nodes with higher case values are | |
65 | later in the list. | |
66 | ||
67 | Switch statements can be output in three forms. A branch table is | |
68 | used if there are more than a few labels and the labels are dense | |
9dfbe515 | 69 | within the range between the smallest and largest case value. If a |
70 | branch table is used, no further manipulations are done with the case | |
71 | node chain. | |
72 | ||
73 | The alternative to the use of a branch table is to generate a series | |
74 | of compare and jump insns. When that is done, we use the LEFT, RIGHT, | |
75 | and PARENT fields to hold a binary tree. Initially the tree is | |
b60acb0b | 76 | totally unbalanced, with everything on the right. We balance the tree |
77 | with nodes on the left having lower case values than the parent | |
9dfbe515 | 78 | and nodes on the right having higher values. We then output the tree |
2ca392fd | 79 | in order. |
80 | ||
81 | For very small, suitable switch statements, we can generate a series | |
82 | of simple bit test and branches instead. */ | |
9dfbe515 | 83 | |
4527a0e8 | 84 | struct case_node |
9dfbe515 | 85 | { |
86 | struct case_node *left; /* Left son in binary tree */ | |
87 | struct case_node *right; /* Right son in binary tree; also node chain */ | |
88 | struct case_node *parent; /* Parent of node in binary tree */ | |
89 | tree low; /* Lowest index value for this label */ | |
90 | tree high; /* Highest index value for this label */ | |
91 | tree code_label; /* Label to jump to when node matches */ | |
92 | }; | |
93 | ||
94 | typedef struct case_node case_node; | |
95 | typedef struct case_node *case_node_ptr; | |
96 | ||
97 | /* These are used by estimate_case_costs and balance_case_nodes. */ | |
98 | ||
99 | /* This must be a signed type, and non-ANSI compilers lack signed char. */ | |
aeee2a4b | 100 | static short cost_table_[129]; |
9dfbe515 | 101 | static int use_cost_table; |
861cd4f3 | 102 | static int cost_table_initialized; |
103 | ||
104 | /* Special care is needed because we allow -1, but TREE_INT_CST_LOW | |
105 | is unsigned. */ | |
47c251e5 | 106 | #define COST_TABLE(I) cost_table_[(unsigned HOST_WIDE_INT) ((I) + 1)] |
9dfbe515 | 107 | \f |
60b8c5b3 | 108 | static int n_occurrences (int, const char *); |
2389b26b | 109 | static bool tree_conflicts_with_clobbers_p (tree, HARD_REG_SET *); |
60b8c5b3 | 110 | static void expand_nl_goto_receiver (void); |
60b8c5b3 | 111 | static bool check_operand_nalternatives (tree, tree); |
112 | static bool check_unique_operand_names (tree, tree); | |
113 | static char *resolve_operand_name_1 (char *, tree, tree); | |
6388f9f7 | 114 | static void expand_null_return_1 (void); |
60b8c5b3 | 115 | static void expand_value_return (rtx); |
60b8c5b3 | 116 | static int estimate_case_costs (case_node_ptr); |
60b8c5b3 | 117 | static bool lshift_cheap_p (void); |
118 | static int case_bit_test_cmp (const void *, const void *); | |
119 | static void emit_case_bit_tests (tree, tree, tree, tree, case_node_ptr, rtx); | |
60b8c5b3 | 120 | static void balance_case_nodes (case_node_ptr *, case_node_ptr); |
121 | static int node_has_low_bound (case_node_ptr, tree); | |
122 | static int node_has_high_bound (case_node_ptr, tree); | |
123 | static int node_is_bounded (case_node_ptr, tree); | |
60b8c5b3 | 124 | static void emit_case_nodes (rtx, case_node_ptr, rtx, tree); |
8bacfa58 | 125 | static struct case_node *add_case_node (struct case_node *, tree, |
4527a0e8 | 126 | tree, tree, tree, alloc_pool); |
bccd9980 | 127 | |
9dfbe515 | 128 | \f |
129 | /* Return the rtx-label that corresponds to a LABEL_DECL, | |
130 | creating it if necessary. */ | |
131 | ||
132 | rtx | |
60b8c5b3 | 133 | label_rtx (tree label) |
9dfbe515 | 134 | { |
04e579b6 | 135 | gcc_assert (TREE_CODE (label) == LABEL_DECL); |
9dfbe515 | 136 | |
0e8e37b2 | 137 | if (!DECL_RTL_SET_P (label)) |
4ee9c684 | 138 | { |
139 | rtx r = gen_label_rtx (); | |
140 | SET_DECL_RTL (label, r); | |
141 | if (FORCED_LABEL (label) || DECL_NONLOCAL (label)) | |
142 | LABEL_PRESERVE_P (r) = 1; | |
143 | } | |
9dfbe515 | 144 | |
0e8e37b2 | 145 | return DECL_RTL (label); |
9dfbe515 | 146 | } |
147 | ||
78a75ebd | 148 | /* As above, but also put it on the forced-reference list of the |
149 | function that contains it. */ | |
150 | rtx | |
60b8c5b3 | 151 | force_label_rtx (tree label) |
78a75ebd | 152 | { |
153 | rtx ref = label_rtx (label); | |
154 | tree function = decl_function_context (label); | |
78a75ebd | 155 | |
04e579b6 | 156 | gcc_assert (function); |
78a75ebd | 157 | |
b079a207 | 158 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, ref, forced_labels); |
78a75ebd | 159 | return ref; |
160 | } | |
0e8e37b2 | 161 | |
9dfbe515 | 162 | /* Add an unconditional jump to LABEL as the next sequential instruction. */ |
163 | ||
164 | void | |
60b8c5b3 | 165 | emit_jump (rtx label) |
9dfbe515 | 166 | { |
167 | do_pending_stack_adjust (); | |
168 | emit_jump_insn (gen_jump (label)); | |
169 | emit_barrier (); | |
170 | } | |
171 | ||
172 | /* Emit code to jump to the address | |
173 | specified by the pointer expression EXP. */ | |
174 | ||
175 | void | |
60b8c5b3 | 176 | expand_computed_goto (tree exp) |
9dfbe515 | 177 | { |
8ec3c5c2 | 178 | rtx x = expand_normal (exp); |
1ca63194 | 179 | |
85d654dd | 180 | x = convert_memory_address (Pmode, x); |
c05e9d61 | 181 | |
939d0e9e | 182 | do_pending_stack_adjust (); |
183 | emit_indirect_jump (x); | |
9dfbe515 | 184 | } |
185 | \f | |
186 | /* Handle goto statements and the labels that they can go to. */ | |
187 | ||
188 | /* Specify the location in the RTL code of a label LABEL, | |
189 | which is a LABEL_DECL tree node. | |
190 | ||
191 | This is used for the kind of label that the user can jump to with a | |
192 | goto statement, and for alternatives of a switch or case statement. | |
193 | RTL labels generated for loops and conditionals don't go through here; | |
194 | they are generated directly at the RTL level, by other functions below. | |
195 | ||
196 | Note that this has nothing to do with defining label *names*. | |
197 | Languages vary in how they do that and what that even means. */ | |
198 | ||
199 | void | |
60b8c5b3 | 200 | expand_label (tree label) |
9dfbe515 | 201 | { |
4ee9c684 | 202 | rtx label_r = label_rtx (label); |
9dfbe515 | 203 | |
204 | do_pending_stack_adjust (); | |
4ee9c684 | 205 | emit_label (label_r); |
9dfbe515 | 206 | if (DECL_NAME (label)) |
207 | LABEL_NAME (DECL_RTL (label)) = IDENTIFIER_POINTER (DECL_NAME (label)); | |
208 | ||
4ee9c684 | 209 | if (DECL_NONLOCAL (label)) |
210 | { | |
211 | expand_nl_goto_receiver (); | |
212 | nonlocal_goto_handler_labels | |
213 | = gen_rtx_EXPR_LIST (VOIDmode, label_r, | |
214 | nonlocal_goto_handler_labels); | |
215 | } | |
216 | ||
217 | if (FORCED_LABEL (label)) | |
218 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, label_r, forced_labels); | |
491e04ef | 219 | |
4ee9c684 | 220 | if (DECL_NONLOCAL (label) || FORCED_LABEL (label)) |
221 | maybe_set_first_label_num (label_r); | |
9dfbe515 | 222 | } |
223 | ||
9dfbe515 | 224 | /* Generate RTL code for a `goto' statement with target label LABEL. |
225 | LABEL should be a LABEL_DECL tree node that was or will later be | |
226 | defined with `expand_label'. */ | |
227 | ||
228 | void | |
60b8c5b3 | 229 | expand_goto (tree label) |
9dfbe515 | 230 | { |
4ee9c684 | 231 | #ifdef ENABLE_CHECKING |
232 | /* Check for a nonlocal goto to a containing function. Should have | |
233 | gotten translated to __builtin_nonlocal_goto. */ | |
234 | tree context = decl_function_context (label); | |
04e579b6 | 235 | gcc_assert (!context || context == current_function_decl); |
9dfbe515 | 236 | #endif |
615166bb | 237 | |
6388f9f7 | 238 | emit_jump (label_rtx (label)); |
9dfbe515 | 239 | } |
ff89ffb2 | 240 | \f |
241 | /* Return the number of times character C occurs in string S. */ | |
242 | static int | |
60b8c5b3 | 243 | n_occurrences (int c, const char *s) |
ff89ffb2 | 244 | { |
245 | int n = 0; | |
246 | while (*s) | |
247 | n += (*s++ == c); | |
248 | return n; | |
249 | } | |
9dfbe515 | 250 | \f |
251 | /* Generate RTL for an asm statement (explicit assembler code). | |
c52051b7 | 252 | STRING is a STRING_CST node containing the assembler code text, |
253 | or an ADDR_EXPR containing a STRING_CST. VOL nonzero means the | |
254 | insn is volatile; don't optimize it. */ | |
9dfbe515 | 255 | |
9bd0c476 | 256 | static void |
09fb10e8 | 257 | expand_asm_loc (tree string, int vol, location_t locus) |
9dfbe515 | 258 | { |
c52051b7 | 259 | rtx body; |
260 | ||
261 | if (TREE_CODE (string) == ADDR_EXPR) | |
262 | string = TREE_OPERAND (string, 0); | |
263 | ||
09fb10e8 | 264 | body = gen_rtx_ASM_INPUT_loc (VOIDmode, |
265 | ggc_strdup (TREE_STRING_POINTER (string)), | |
266 | locus); | |
c52051b7 | 267 | |
268 | MEM_VOLATILE_P (body) = vol; | |
9dfbe515 | 269 | |
c52051b7 | 270 | emit_insn (body); |
9dfbe515 | 271 | } |
272 | ||
37c0f956 | 273 | /* Parse the output constraint pointed to by *CONSTRAINT_P. It is the |
274 | OPERAND_NUMth output operand, indexed from zero. There are NINPUTS | |
275 | inputs and NOUTPUTS outputs to this extended-asm. Upon return, | |
276 | *ALLOWS_MEM will be TRUE iff the constraint allows the use of a | |
277 | memory operand. Similarly, *ALLOWS_REG will be TRUE iff the | |
278 | constraint allows the use of a register operand. And, *IS_INOUT | |
279 | will be true if the operand is read-write, i.e., if it is used as | |
280 | an input as well as an output. If *CONSTRAINT_P is not in | |
281 | canonical form, it will be made canonical. (Note that `+' will be | |
de132707 | 282 | replaced with `=' as part of this process.) |
37c0f956 | 283 | |
284 | Returns TRUE if all went well; FALSE if an error occurred. */ | |
285 | ||
286 | bool | |
60b8c5b3 | 287 | parse_output_constraint (const char **constraint_p, int operand_num, |
288 | int ninputs, int noutputs, bool *allows_mem, | |
289 | bool *allows_reg, bool *is_inout) | |
37c0f956 | 290 | { |
291 | const char *constraint = *constraint_p; | |
292 | const char *p; | |
293 | ||
294 | /* Assume the constraint doesn't allow the use of either a register | |
295 | or memory. */ | |
296 | *allows_mem = false; | |
297 | *allows_reg = false; | |
298 | ||
299 | /* Allow the `=' or `+' to not be at the beginning of the string, | |
300 | since it wasn't explicitly documented that way, and there is a | |
301 | large body of code that puts it last. Swap the character to | |
302 | the front, so as not to uglify any place else. */ | |
303 | p = strchr (constraint, '='); | |
304 | if (!p) | |
305 | p = strchr (constraint, '+'); | |
306 | ||
307 | /* If the string doesn't contain an `=', issue an error | |
308 | message. */ | |
309 | if (!p) | |
310 | { | |
eb586f2c | 311 | error ("output operand constraint lacks %<=%>"); |
37c0f956 | 312 | return false; |
313 | } | |
314 | ||
315 | /* If the constraint begins with `+', then the operand is both read | |
316 | from and written to. */ | |
317 | *is_inout = (*p == '+'); | |
318 | ||
37c0f956 | 319 | /* Canonicalize the output constraint so that it begins with `='. */ |
d72a7307 | 320 | if (p != constraint || *is_inout) |
37c0f956 | 321 | { |
322 | char *buf; | |
323 | size_t c_len = strlen (constraint); | |
324 | ||
325 | if (p != constraint) | |
c3ceba8e | 326 | warning (0, "output constraint %qc for operand %d " |
eb586f2c | 327 | "is not at the beginning", |
37c0f956 | 328 | *p, operand_num); |
329 | ||
330 | /* Make a copy of the constraint. */ | |
f7f3687c | 331 | buf = XALLOCAVEC (char, c_len + 1); |
37c0f956 | 332 | strcpy (buf, constraint); |
333 | /* Swap the first character and the `=' or `+'. */ | |
334 | buf[p - constraint] = buf[0]; | |
335 | /* Make sure the first character is an `='. (Until we do this, | |
336 | it might be a `+'.) */ | |
337 | buf[0] = '='; | |
338 | /* Replace the constraint with the canonicalized string. */ | |
339 | *constraint_p = ggc_alloc_string (buf, c_len); | |
340 | constraint = *constraint_p; | |
341 | } | |
342 | ||
343 | /* Loop through the constraint string. */ | |
48ea5577 | 344 | for (p = constraint + 1; *p; p += CONSTRAINT_LEN (*p, p)) |
37c0f956 | 345 | switch (*p) |
346 | { | |
347 | case '+': | |
348 | case '=': | |
eb586f2c | 349 | error ("operand constraint contains incorrectly positioned " |
350 | "%<+%> or %<=%>"); | |
37c0f956 | 351 | return false; |
40734805 | 352 | |
37c0f956 | 353 | case '%': |
354 | if (operand_num + 1 == ninputs + noutputs) | |
355 | { | |
eb586f2c | 356 | error ("%<%%%> constraint used with last operand"); |
37c0f956 | 357 | return false; |
358 | } | |
359 | break; | |
360 | ||
e9ff93b1 | 361 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
37c0f956 | 362 | *allows_mem = true; |
363 | break; | |
364 | ||
365 | case '?': case '!': case '*': case '&': case '#': | |
366 | case 'E': case 'F': case 'G': case 'H': | |
367 | case 's': case 'i': case 'n': | |
368 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
369 | case 'N': case 'O': case 'P': case ',': | |
370 | break; | |
371 | ||
372 | case '0': case '1': case '2': case '3': case '4': | |
373 | case '5': case '6': case '7': case '8': case '9': | |
2c7f203c | 374 | case '[': |
37c0f956 | 375 | error ("matching constraint not valid in output operand"); |
376 | return false; | |
377 | ||
378 | case '<': case '>': | |
379 | /* ??? Before flow, auto inc/dec insns are not supposed to exist, | |
380 | excepting those that expand_call created. So match memory | |
381 | and hope. */ | |
382 | *allows_mem = true; | |
383 | break; | |
384 | ||
385 | case 'g': case 'X': | |
386 | *allows_reg = true; | |
387 | *allows_mem = true; | |
388 | break; | |
40734805 | 389 | |
37c0f956 | 390 | case 'p': case 'r': |
391 | *allows_reg = true; | |
392 | break; | |
393 | ||
394 | default: | |
395 | if (!ISALPHA (*p)) | |
396 | break; | |
48ea5577 | 397 | if (REG_CLASS_FROM_CONSTRAINT (*p, p) != NO_REGS) |
37c0f956 | 398 | *allows_reg = true; |
48ea5577 | 399 | #ifdef EXTRA_CONSTRAINT_STR |
400 | else if (EXTRA_ADDRESS_CONSTRAINT (*p, p)) | |
a5004c3d | 401 | *allows_reg = true; |
48ea5577 | 402 | else if (EXTRA_MEMORY_CONSTRAINT (*p, p)) |
a5004c3d | 403 | *allows_mem = true; |
37c0f956 | 404 | else |
405 | { | |
406 | /* Otherwise we can't assume anything about the nature of | |
407 | the constraint except that it isn't purely registers. | |
408 | Treat it like "g" and hope for the best. */ | |
409 | *allows_reg = true; | |
410 | *allows_mem = true; | |
411 | } | |
412 | #endif | |
413 | break; | |
414 | } | |
415 | ||
416 | return true; | |
417 | } | |
418 | ||
727dae1b | 419 | /* Similar, but for input constraints. */ |
420 | ||
d7e38994 | 421 | bool |
60b8c5b3 | 422 | parse_input_constraint (const char **constraint_p, int input_num, |
423 | int ninputs, int noutputs, int ninout, | |
424 | const char * const * constraints, | |
425 | bool *allows_mem, bool *allows_reg) | |
727dae1b | 426 | { |
427 | const char *constraint = *constraint_p; | |
428 | const char *orig_constraint = constraint; | |
429 | size_t c_len = strlen (constraint); | |
430 | size_t j; | |
23ec9bd9 | 431 | bool saw_match = false; |
727dae1b | 432 | |
433 | /* Assume the constraint doesn't allow the use of either | |
434 | a register or memory. */ | |
435 | *allows_mem = false; | |
436 | *allows_reg = false; | |
437 | ||
438 | /* Make sure constraint has neither `=', `+', nor '&'. */ | |
439 | ||
48ea5577 | 440 | for (j = 0; j < c_len; j += CONSTRAINT_LEN (constraint[j], constraint+j)) |
727dae1b | 441 | switch (constraint[j]) |
442 | { | |
443 | case '+': case '=': case '&': | |
444 | if (constraint == orig_constraint) | |
445 | { | |
eb586f2c | 446 | error ("input operand constraint contains %qc", constraint[j]); |
727dae1b | 447 | return false; |
448 | } | |
449 | break; | |
450 | ||
451 | case '%': | |
452 | if (constraint == orig_constraint | |
453 | && input_num + 1 == ninputs - ninout) | |
454 | { | |
eb586f2c | 455 | error ("%<%%%> constraint used with last operand"); |
727dae1b | 456 | return false; |
457 | } | |
458 | break; | |
459 | ||
e9ff93b1 | 460 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
727dae1b | 461 | *allows_mem = true; |
462 | break; | |
463 | ||
464 | case '<': case '>': | |
465 | case '?': case '!': case '*': case '#': | |
466 | case 'E': case 'F': case 'G': case 'H': | |
467 | case 's': case 'i': case 'n': | |
468 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
469 | case 'N': case 'O': case 'P': case ',': | |
470 | break; | |
471 | ||
472 | /* Whether or not a numeric constraint allows a register is | |
473 | decided by the matching constraint, and so there is no need | |
474 | to do anything special with them. We must handle them in | |
475 | the default case, so that we don't unnecessarily force | |
476 | operands to memory. */ | |
477 | case '0': case '1': case '2': case '3': case '4': | |
478 | case '5': case '6': case '7': case '8': case '9': | |
479 | { | |
480 | char *end; | |
481 | unsigned long match; | |
482 | ||
23ec9bd9 | 483 | saw_match = true; |
484 | ||
727dae1b | 485 | match = strtoul (constraint + j, &end, 10); |
486 | if (match >= (unsigned long) noutputs) | |
487 | { | |
488 | error ("matching constraint references invalid operand number"); | |
489 | return false; | |
490 | } | |
491 | ||
492 | /* Try and find the real constraint for this dup. Only do this | |
493 | if the matching constraint is the only alternative. */ | |
494 | if (*end == '\0' | |
495 | && (j == 0 || (j == 1 && constraint[0] == '%'))) | |
496 | { | |
497 | constraint = constraints[match]; | |
498 | *constraint_p = constraint; | |
499 | c_len = strlen (constraint); | |
500 | j = 0; | |
48ea5577 | 501 | /* ??? At the end of the loop, we will skip the first part of |
502 | the matched constraint. This assumes not only that the | |
503 | other constraint is an output constraint, but also that | |
504 | the '=' or '+' come first. */ | |
727dae1b | 505 | break; |
506 | } | |
507 | else | |
508 | j = end - constraint; | |
48ea5577 | 509 | /* Anticipate increment at end of loop. */ |
510 | j--; | |
727dae1b | 511 | } |
512 | /* Fall through. */ | |
513 | ||
514 | case 'p': case 'r': | |
515 | *allows_reg = true; | |
516 | break; | |
517 | ||
518 | case 'g': case 'X': | |
519 | *allows_reg = true; | |
520 | *allows_mem = true; | |
521 | break; | |
522 | ||
523 | default: | |
524 | if (! ISALPHA (constraint[j])) | |
525 | { | |
eb586f2c | 526 | error ("invalid punctuation %qc in constraint", constraint[j]); |
727dae1b | 527 | return false; |
528 | } | |
48ea5577 | 529 | if (REG_CLASS_FROM_CONSTRAINT (constraint[j], constraint + j) |
530 | != NO_REGS) | |
727dae1b | 531 | *allows_reg = true; |
48ea5577 | 532 | #ifdef EXTRA_CONSTRAINT_STR |
533 | else if (EXTRA_ADDRESS_CONSTRAINT (constraint[j], constraint + j)) | |
a5004c3d | 534 | *allows_reg = true; |
48ea5577 | 535 | else if (EXTRA_MEMORY_CONSTRAINT (constraint[j], constraint + j)) |
a5004c3d | 536 | *allows_mem = true; |
727dae1b | 537 | else |
538 | { | |
539 | /* Otherwise we can't assume anything about the nature of | |
540 | the constraint except that it isn't purely registers. | |
541 | Treat it like "g" and hope for the best. */ | |
542 | *allows_reg = true; | |
543 | *allows_mem = true; | |
544 | } | |
545 | #endif | |
546 | break; | |
547 | } | |
548 | ||
23ec9bd9 | 549 | if (saw_match && !*allows_reg) |
c3ceba8e | 550 | warning (0, "matching constraint does not allow a register"); |
23ec9bd9 | 551 | |
727dae1b | 552 | return true; |
553 | } | |
554 | ||
2389b26b | 555 | /* Return DECL iff there's an overlap between *REGS and DECL, where DECL |
556 | can be an asm-declared register. Called via walk_tree. */ | |
3d52d305 | 557 | |
2389b26b | 558 | static tree |
559 | decl_overlaps_hard_reg_set_p (tree *declp, int *walk_subtrees ATTRIBUTE_UNUSED, | |
560 | void *data) | |
3d52d305 | 561 | { |
2389b26b | 562 | tree decl = *declp; |
f7f3687c | 563 | const HARD_REG_SET *const regs = (const HARD_REG_SET *) data; |
2389b26b | 564 | |
56753e9d | 565 | if (TREE_CODE (decl) == VAR_DECL) |
3d52d305 | 566 | { |
56753e9d | 567 | if (DECL_HARD_REGISTER (decl) |
2389b26b | 568 | && REG_P (DECL_RTL (decl)) |
569 | && REGNO (DECL_RTL (decl)) < FIRST_PSEUDO_REGISTER) | |
570 | { | |
571 | rtx reg = DECL_RTL (decl); | |
a2c6f0b7 | 572 | |
573 | if (overlaps_hard_reg_set_p (*regs, GET_MODE (reg), REGNO (reg))) | |
574 | return decl; | |
2389b26b | 575 | } |
576 | walk_subtrees = 0; | |
64d5fb6a | 577 | } |
56753e9d | 578 | else if (TYPE_P (decl) || TREE_CODE (decl) == PARM_DECL) |
2389b26b | 579 | walk_subtrees = 0; |
580 | return NULL_TREE; | |
64d5fb6a | 581 | } |
582 | ||
2389b26b | 583 | /* If there is an overlap between *REGS and DECL, return the first overlap |
584 | found. */ | |
585 | tree | |
586 | tree_overlaps_hard_reg_set (tree decl, HARD_REG_SET *regs) | |
587 | { | |
588 | return walk_tree (&decl, decl_overlaps_hard_reg_set_p, regs, NULL); | |
589 | } | |
64d5fb6a | 590 | |
591 | /* Check for overlap between registers marked in CLOBBERED_REGS and | |
2389b26b | 592 | anything inappropriate in T. Emit error and return the register |
593 | variable definition for error, NULL_TREE for ok. */ | |
64d5fb6a | 594 | |
595 | static bool | |
2389b26b | 596 | tree_conflicts_with_clobbers_p (tree t, HARD_REG_SET *clobbered_regs) |
64d5fb6a | 597 | { |
598 | /* Conflicts between asm-declared register variables and the clobber | |
599 | list are not allowed. */ | |
2389b26b | 600 | tree overlap = tree_overlaps_hard_reg_set (t, clobbered_regs); |
601 | ||
602 | if (overlap) | |
64d5fb6a | 603 | { |
abd3e6b5 | 604 | error ("asm-specifier for variable %qE conflicts with asm clobber list", |
605 | DECL_NAME (overlap)); | |
64d5fb6a | 606 | |
607 | /* Reset registerness to stop multiple errors emitted for a single | |
608 | variable. */ | |
2389b26b | 609 | DECL_REGISTER (overlap) = 0; |
64d5fb6a | 610 | return true; |
3d52d305 | 611 | } |
64d5fb6a | 612 | |
3d52d305 | 613 | return false; |
614 | } | |
615 | ||
9dfbe515 | 616 | /* Generate RTL for an asm statement with arguments. |
617 | STRING is the instruction template. | |
618 | OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs. | |
619 | Each output or input has an expression in the TREE_VALUE and | |
f0b5f617 | 620 | a tree list in TREE_PURPOSE which in turn contains a constraint |
40734805 | 621 | name in TREE_VALUE (or NULL_TREE) and a constraint string |
598b3ed1 | 622 | in TREE_PURPOSE. |
9dfbe515 | 623 | CLOBBERS is a list of STRING_CST nodes each naming a hard register |
624 | that is clobbered by this insn. | |
625 | ||
626 | Not all kinds of lvalue that may appear in OUTPUTS can be stored directly. | |
627 | Some elements of OUTPUTS may be replaced with trees representing temporary | |
628 | values. The caller should copy those temporary values to the originally | |
629 | specified lvalues. | |
630 | ||
631 | VOL nonzero means the insn is volatile; don't optimize it. */ | |
632 | ||
9bd0c476 | 633 | static void |
60b8c5b3 | 634 | expand_asm_operands (tree string, tree outputs, tree inputs, |
867bd639 | 635 | tree clobbers, int vol, location_t locus) |
9dfbe515 | 636 | { |
2c7f203c | 637 | rtvec argvec, constraintvec; |
9dfbe515 | 638 | rtx body; |
639 | int ninputs = list_length (inputs); | |
640 | int noutputs = list_length (outputs); | |
727dae1b | 641 | int ninout; |
add87c42 | 642 | int nclobbers; |
3d52d305 | 643 | HARD_REG_SET clobbered_regs; |
644 | int clobber_conflict_found = 0; | |
9dfbe515 | 645 | tree tail; |
ef13e68f | 646 | tree t; |
19cb6b50 | 647 | int i; |
9dfbe515 | 648 | /* Vector of RTX's of evaluated output operands. */ |
f7f3687c | 649 | rtx *output_rtx = XALLOCAVEC (rtx, noutputs); |
650 | int *inout_opnum = XALLOCAVEC (int, noutputs); | |
651 | rtx *real_output_rtx = XALLOCAVEC (rtx, noutputs); | |
652 | enum machine_mode *inout_mode = XALLOCAVEC (enum machine_mode, noutputs); | |
653 | const char **constraints = XALLOCAVEC (const char *, noutputs + ninputs); | |
316bc009 | 654 | int old_generating_concat_p = generating_concat_p; |
9dfbe515 | 655 | |
997d68fe | 656 | /* An ASM with no outputs needs to be treated as volatile, for now. */ |
69bbada3 | 657 | if (noutputs == 0) |
658 | vol = 1; | |
659 | ||
2c7f203c | 660 | if (! check_operand_nalternatives (outputs, inputs)) |
661 | return; | |
662 | ||
ef13e68f | 663 | string = resolve_asm_operand_names (string, outputs, inputs); |
664 | ||
665 | /* Collect constraints. */ | |
666 | i = 0; | |
667 | for (t = outputs; t ; t = TREE_CHAIN (t), i++) | |
668 | constraints[i] = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); | |
669 | for (t = inputs; t ; t = TREE_CHAIN (t), i++) | |
670 | constraints[i] = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); | |
2c7f203c | 671 | |
b83e57f8 | 672 | /* Sometimes we wish to automatically clobber registers across an asm. |
673 | Case in point is when the i386 backend moved from cc0 to a hard reg -- | |
dd5b4b36 | 674 | maintaining source-level compatibility means automatically clobbering |
b83e57f8 | 675 | the flags register. */ |
64d5fb6a | 676 | clobbers = targetm.md_asm_clobbers (outputs, inputs, clobbers); |
b83e57f8 | 677 | |
add87c42 | 678 | /* Count the number of meaningful clobbered registers, ignoring what |
679 | we would ignore later. */ | |
680 | nclobbers = 0; | |
3d52d305 | 681 | CLEAR_HARD_REG_SET (clobbered_regs); |
add87c42 | 682 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) |
683 | { | |
b3790f16 | 684 | const char *regname; |
685 | ||
686 | if (TREE_VALUE (tail) == error_mark_node) | |
687 | return; | |
688 | regname = TREE_STRING_POINTER (TREE_VALUE (tail)); | |
155b05dc | 689 | |
426b38c9 | 690 | i = decode_reg_name (regname); |
691 | if (i >= 0 || i == -4) | |
add87c42 | 692 | ++nclobbers; |
fd8b69ed | 693 | else if (i == -2) |
eb586f2c | 694 | error ("unknown register name %qs in %<asm%>", regname); |
3d52d305 | 695 | |
696 | /* Mark clobbered registers. */ | |
697 | if (i >= 0) | |
e433ac65 | 698 | { |
778ac06a | 699 | /* Clobbering the PIC register is an error. */ |
3473aefe | 700 | if (i == (int) PIC_OFFSET_TABLE_REGNUM) |
e433ac65 | 701 | { |
eb586f2c | 702 | error ("PIC register %qs clobbered in %<asm%>", regname); |
e433ac65 | 703 | return; |
704 | } | |
705 | ||
706 | SET_HARD_REG_BIT (clobbered_regs, i); | |
707 | } | |
add87c42 | 708 | } |
709 | ||
727dae1b | 710 | /* First pass over inputs and outputs checks validity and sets |
711 | mark_addressable if needed. */ | |
712 | ||
713 | ninout = 0; | |
9dfbe515 | 714 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
715 | { | |
716 | tree val = TREE_VALUE (tail); | |
f7af3d34 | 717 | tree type = TREE_TYPE (val); |
727dae1b | 718 | const char *constraint; |
37c0f956 | 719 | bool is_inout; |
720 | bool allows_reg; | |
721 | bool allows_mem; | |
9dfbe515 | 722 | |
723 | /* If there's an erroneous arg, emit no insn. */ | |
37c0f956 | 724 | if (type == error_mark_node) |
9dfbe515 | 725 | return; |
726 | ||
37c0f956 | 727 | /* Try to parse the output constraint. If that fails, there's |
728 | no point in going further. */ | |
727dae1b | 729 | constraint = constraints[i]; |
730 | if (!parse_output_constraint (&constraint, i, ninputs, noutputs, | |
731 | &allows_mem, &allows_reg, &is_inout)) | |
732 | return; | |
733 | ||
734 | if (! allows_reg | |
735 | && (allows_mem | |
736 | || is_inout | |
737 | || (DECL_P (val) | |
8ad4c111 | 738 | && REG_P (DECL_RTL (val)) |
727dae1b | 739 | && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type)))) |
dc24ddbd | 740 | lang_hooks.mark_addressable (val); |
727dae1b | 741 | |
742 | if (is_inout) | |
743 | ninout++; | |
744 | } | |
745 | ||
746 | ninputs += ninout; | |
747 | if (ninputs + noutputs > MAX_RECOG_OPERANDS) | |
748 | { | |
eb586f2c | 749 | error ("more than %d operands in %<asm%>", MAX_RECOG_OPERANDS); |
727dae1b | 750 | return; |
751 | } | |
752 | ||
753 | for (i = 0, tail = inputs; tail; i++, tail = TREE_CHAIN (tail)) | |
754 | { | |
755 | bool allows_reg, allows_mem; | |
756 | const char *constraint; | |
757 | ||
758 | /* If there's an erroneous arg, emit no insn, because the ASM_INPUT | |
759 | would get VOIDmode and that could cause a crash in reload. */ | |
760 | if (TREE_TYPE (TREE_VALUE (tail)) == error_mark_node) | |
761 | return; | |
762 | ||
763 | constraint = constraints[i + noutputs]; | |
764 | if (! parse_input_constraint (&constraint, i, ninputs, noutputs, ninout, | |
765 | constraints, &allows_mem, &allows_reg)) | |
37c0f956 | 766 | return; |
4beb7473 | 767 | |
727dae1b | 768 | if (! allows_reg && allows_mem) |
dc24ddbd | 769 | lang_hooks.mark_addressable (TREE_VALUE (tail)); |
727dae1b | 770 | } |
771 | ||
772 | /* Second pass evaluates arguments. */ | |
773 | ||
774 | ninout = 0; | |
775 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
776 | { | |
777 | tree val = TREE_VALUE (tail); | |
778 | tree type = TREE_TYPE (val); | |
779 | bool is_inout; | |
780 | bool allows_reg; | |
781 | bool allows_mem; | |
154ffe7e | 782 | rtx op; |
04e579b6 | 783 | bool ok; |
727dae1b | 784 | |
04e579b6 | 785 | ok = parse_output_constraint (&constraints[i], i, ninputs, |
727dae1b | 786 | noutputs, &allows_mem, &allows_reg, |
04e579b6 | 787 | &is_inout); |
788 | gcc_assert (ok); | |
727dae1b | 789 | |
4beb7473 | 790 | /* If an output operand is not a decl or indirect ref and our constraint |
791 | allows a register, make a temporary to act as an intermediate. | |
792 | Make the asm insn write into that, then our caller will copy it to | |
793 | the real output operand. Likewise for promoted variables. */ | |
9dfbe515 | 794 | |
316bc009 | 795 | generating_concat_p = 0; |
796 | ||
adc27eec | 797 | real_output_rtx[i] = NULL_RTX; |
24871a8e | 798 | if ((TREE_CODE (val) == INDIRECT_REF |
799 | && allows_mem) | |
9308e976 | 800 | || (DECL_P (val) |
8ad4c111 | 801 | && (allows_mem || REG_P (DECL_RTL (val))) |
802 | && ! (REG_P (DECL_RTL (val)) | |
4beb7473 | 803 | && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type))) |
9e03c9f8 | 804 | || ! allows_reg |
ff89ffb2 | 805 | || is_inout) |
4beb7473 | 806 | { |
154ffe7e | 807 | op = expand_expr (val, NULL_RTX, VOIDmode, EXPAND_WRITE); |
e16ceb8e | 808 | if (MEM_P (op)) |
154ffe7e | 809 | op = validize_mem (op); |
4beb7473 | 810 | |
e16ceb8e | 811 | if (! allows_reg && !MEM_P (op)) |
4beb7473 | 812 | error ("output number %d not directly addressable", i); |
e16ceb8e | 813 | if ((! allows_mem && MEM_P (op)) |
154ffe7e | 814 | || GET_CODE (op) == CONCAT) |
adc27eec | 815 | { |
0a534ba7 | 816 | real_output_rtx[i] = op; |
154ffe7e | 817 | op = gen_reg_rtx (GET_MODE (op)); |
9e03c9f8 | 818 | if (is_inout) |
154ffe7e | 819 | emit_move_insn (op, real_output_rtx[i]); |
adc27eec | 820 | } |
4beb7473 | 821 | } |
f7af3d34 | 822 | else |
5ea3104e | 823 | { |
154ffe7e | 824 | op = assign_temp (type, 0, 0, 1); |
825 | op = validize_mem (op); | |
826 | TREE_VALUE (tail) = make_tree (type, op); | |
f7af3d34 | 827 | } |
154ffe7e | 828 | output_rtx[i] = op; |
04d020d0 | 829 | |
316bc009 | 830 | generating_concat_p = old_generating_concat_p; |
831 | ||
ff89ffb2 | 832 | if (is_inout) |
04d020d0 | 833 | { |
727dae1b | 834 | inout_mode[ninout] = TYPE_MODE (type); |
04d020d0 | 835 | inout_opnum[ninout++] = i; |
836 | } | |
3d52d305 | 837 | |
2389b26b | 838 | if (tree_conflicts_with_clobbers_p (val, &clobbered_regs)) |
3d52d305 | 839 | clobber_conflict_found = 1; |
9dfbe515 | 840 | } |
841 | ||
2c7f203c | 842 | /* Make vectors for the expression-rtx, constraint strings, |
843 | and named operands. */ | |
9dfbe515 | 844 | |
845 | argvec = rtvec_alloc (ninputs); | |
2c7f203c | 846 | constraintvec = rtvec_alloc (ninputs); |
9dfbe515 | 847 | |
d91f2122 | 848 | body = gen_rtx_ASM_OPERANDS ((noutputs == 0 ? VOIDmode |
849 | : GET_MODE (output_rtx[0])), | |
d5406300 | 850 | ggc_strdup (TREE_STRING_POINTER (string)), |
2c7f203c | 851 | empty_string, 0, argvec, constraintvec, |
7bd3dcc4 | 852 | locus); |
220345e0 | 853 | |
ab12bb63 | 854 | MEM_VOLATILE_P (body) = vol; |
9dfbe515 | 855 | |
856 | /* Eval the inputs and put them into ARGVEC. | |
857 | Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */ | |
858 | ||
2c7f203c | 859 | for (i = 0, tail = inputs; tail; tail = TREE_CHAIN (tail), ++i) |
9dfbe515 | 860 | { |
727dae1b | 861 | bool allows_reg, allows_mem; |
862 | const char *constraint; | |
863 | tree val, type; | |
6d2e66f1 | 864 | rtx op; |
04e579b6 | 865 | bool ok; |
9dfbe515 | 866 | |
727dae1b | 867 | constraint = constraints[i + noutputs]; |
04e579b6 | 868 | ok = parse_input_constraint (&constraint, i, ninputs, noutputs, ninout, |
869 | constraints, &allows_mem, &allows_reg); | |
870 | gcc_assert (ok); | |
ff89ffb2 | 871 | |
727dae1b | 872 | generating_concat_p = 0; |
01b88844 | 873 | |
727dae1b | 874 | val = TREE_VALUE (tail); |
875 | type = TREE_TYPE (val); | |
41527000 | 876 | /* EXPAND_INITIALIZER will not generate code for valid initializer |
877 | constants, but will still generate code for other types of operand. | |
878 | This is the behavior we want for constant constraints. */ | |
68b956ae | 879 | op = expand_expr (val, NULL_RTX, VOIDmode, |
41527000 | 880 | allows_reg ? EXPAND_NORMAL |
881 | : allows_mem ? EXPAND_MEMORY | |
882 | : EXPAND_INITIALIZER); | |
01b88844 | 883 | |
316bc009 | 884 | /* Never pass a CONCAT to an ASM. */ |
316bc009 | 885 | if (GET_CODE (op) == CONCAT) |
886 | op = force_reg (GET_MODE (op), op); | |
e16ceb8e | 887 | else if (MEM_P (op)) |
154ffe7e | 888 | op = validize_mem (op); |
316bc009 | 889 | |
cde8f1c8 | 890 | if (asm_operand_ok (op, constraint, NULL) <= 0) |
01b88844 | 891 | { |
3bcb100d | 892 | if (allows_reg && TYPE_MODE (type) != BLKmode) |
727dae1b | 893 | op = force_reg (TYPE_MODE (type), op); |
9e03c9f8 | 894 | else if (!allows_mem) |
c3ceba8e | 895 | warning (0, "asm operand %d probably doesn%'t match constraints", |
2c7f203c | 896 | i + noutputs); |
e16ceb8e | 897 | else if (MEM_P (op)) |
727dae1b | 898 | { |
0c7968a1 | 899 | /* We won't recognize either volatile memory or memory |
900 | with a queued address as available a memory_operand | |
901 | at this point. Ignore it: clearly this *is* a memory. */ | |
727dae1b | 902 | } |
6d2e66f1 | 903 | else |
68b956ae | 904 | { |
c3ceba8e | 905 | warning (0, "use of memory input without lvalue in " |
5eae4518 | 906 | "asm operand %d is deprecated", i + noutputs); |
68b956ae | 907 | |
908 | if (CONSTANT_P (op)) | |
909 | { | |
875abd36 | 910 | rtx mem = force_const_mem (TYPE_MODE (type), op); |
911 | if (mem) | |
912 | op = validize_mem (mem); | |
913 | else | |
914 | op = force_reg (TYPE_MODE (type), op); | |
68b956ae | 915 | } |
8ad4c111 | 916 | if (REG_P (op) |
875abd36 | 917 | || GET_CODE (op) == SUBREG |
875abd36 | 918 | || GET_CODE (op) == CONCAT) |
68b956ae | 919 | { |
920 | tree qual_type = build_qualified_type (type, | |
921 | (TYPE_QUALS (type) | |
922 | | TYPE_QUAL_CONST)); | |
923 | rtx memloc = assign_temp (qual_type, 1, 1, 1); | |
924 | memloc = validize_mem (memloc); | |
925 | emit_move_insn (memloc, op); | |
926 | op = memloc; | |
927 | } | |
928 | } | |
01b88844 | 929 | } |
727dae1b | 930 | |
316bc009 | 931 | generating_concat_p = old_generating_concat_p; |
d91f2122 | 932 | ASM_OPERANDS_INPUT (body, i) = op; |
ff89ffb2 | 933 | |
d91f2122 | 934 | ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body, i) |
d5406300 | 935 | = gen_rtx_ASM_INPUT (TYPE_MODE (type), |
936 | ggc_strdup (constraints[i + noutputs])); | |
3d52d305 | 937 | |
2389b26b | 938 | if (tree_conflicts_with_clobbers_p (val, &clobbered_regs)) |
3d52d305 | 939 | clobber_conflict_found = 1; |
9dfbe515 | 940 | } |
941 | ||
155b05dc | 942 | /* Protect all the operands from the queue now that they have all been |
943 | evaluated. */ | |
9dfbe515 | 944 | |
316bc009 | 945 | generating_concat_p = 0; |
946 | ||
67610d42 | 947 | /* For in-out operands, copy output rtx to input rtx. */ |
04d020d0 | 948 | for (i = 0; i < ninout; i++) |
949 | { | |
04d020d0 | 950 | int j = inout_opnum[i]; |
2c7f203c | 951 | char buffer[16]; |
04d020d0 | 952 | |
d91f2122 | 953 | ASM_OPERANDS_INPUT (body, ninputs - ninout + i) |
04d020d0 | 954 | = output_rtx[j]; |
2c7f203c | 955 | |
956 | sprintf (buffer, "%d", j); | |
d91f2122 | 957 | ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body, ninputs - ninout + i) |
6327cf58 | 958 | = gen_rtx_ASM_INPUT (inout_mode[i], ggc_strdup (buffer)); |
04d020d0 | 959 | } |
960 | ||
316bc009 | 961 | generating_concat_p = old_generating_concat_p; |
962 | ||
9dfbe515 | 963 | /* Now, for each output, construct an rtx |
2c7f203c | 964 | (set OUTPUT (asm_operands INSN OUTPUTCONSTRAINT OUTPUTNUMBER |
965 | ARGVEC CONSTRAINTS OPNAMES)) | |
9dfbe515 | 966 | If there is more than one, put them inside a PARALLEL. */ |
967 | ||
968 | if (noutputs == 1 && nclobbers == 0) | |
969 | { | |
d5406300 | 970 | ASM_OPERANDS_OUTPUT_CONSTRAINT (body) = ggc_strdup (constraints[0]); |
805e22b2 | 971 | emit_insn (gen_rtx_SET (VOIDmode, output_rtx[0], body)); |
9dfbe515 | 972 | } |
155b05dc | 973 | |
9dfbe515 | 974 | else if (noutputs == 0 && nclobbers == 0) |
975 | { | |
976 | /* No output operands: put in a raw ASM_OPERANDS rtx. */ | |
805e22b2 | 977 | emit_insn (body); |
9dfbe515 | 978 | } |
155b05dc | 979 | |
9dfbe515 | 980 | else |
981 | { | |
982 | rtx obody = body; | |
983 | int num = noutputs; | |
155b05dc | 984 | |
985 | if (num == 0) | |
986 | num = 1; | |
987 | ||
941522d6 | 988 | body = gen_rtx_PARALLEL (VOIDmode, rtvec_alloc (num + nclobbers)); |
9dfbe515 | 989 | |
990 | /* For each output operand, store a SET. */ | |
9dfbe515 | 991 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
992 | { | |
993 | XVECEXP (body, 0, i) | |
941522d6 | 994 | = gen_rtx_SET (VOIDmode, |
995 | output_rtx[i], | |
7014838c | 996 | gen_rtx_ASM_OPERANDS |
d91f2122 | 997 | (GET_MODE (output_rtx[i]), |
d5406300 | 998 | ggc_strdup (TREE_STRING_POINTER (string)), |
999 | ggc_strdup (constraints[i]), | |
1000 | i, argvec, constraintvec, locus)); | |
7014838c | 1001 | |
9dfbe515 | 1002 | MEM_VOLATILE_P (SET_SRC (XVECEXP (body, 0, i))) = vol; |
1003 | } | |
1004 | ||
1005 | /* If there are no outputs (but there are some clobbers) | |
1006 | store the bare ASM_OPERANDS into the PARALLEL. */ | |
1007 | ||
1008 | if (i == 0) | |
1009 | XVECEXP (body, 0, i++) = obody; | |
1010 | ||
1011 | /* Store (clobber REG) for each clobbered register specified. */ | |
1012 | ||
add87c42 | 1013 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) |
9dfbe515 | 1014 | { |
a61deedf | 1015 | const char *regname = TREE_STRING_POINTER (TREE_VALUE (tail)); |
bdf74c8a | 1016 | int j = decode_reg_name (regname); |
3d52d305 | 1017 | rtx clobbered_reg; |
9dfbe515 | 1018 | |
bdf74c8a | 1019 | if (j < 0) |
9dfbe515 | 1020 | { |
426b38c9 | 1021 | if (j == -3) /* `cc', which is not a register */ |
48c6936b | 1022 | continue; |
1023 | ||
426b38c9 | 1024 | if (j == -4) /* `memory', don't cache memory across asm */ |
1025 | { | |
665446b8 | 1026 | XVECEXP (body, 0, i++) |
941522d6 | 1027 | = gen_rtx_CLOBBER (VOIDmode, |
7014838c | 1028 | gen_rtx_MEM |
1029 | (BLKmode, | |
1030 | gen_rtx_SCRATCH (VOIDmode))); | |
426b38c9 | 1031 | continue; |
1032 | } | |
1033 | ||
ad87de1e | 1034 | /* Ignore unknown register, error already signaled. */ |
c9cba93a | 1035 | continue; |
9dfbe515 | 1036 | } |
1037 | ||
1038 | /* Use QImode since that's guaranteed to clobber just one reg. */ | |
3d52d305 | 1039 | clobbered_reg = gen_rtx_REG (QImode, j); |
1040 | ||
1041 | /* Do sanity check for overlap between clobbers and respectively | |
1042 | input and outputs that hasn't been handled. Such overlap | |
1043 | should have been detected and reported above. */ | |
1044 | if (!clobber_conflict_found) | |
1045 | { | |
1046 | int opno; | |
1047 | ||
1048 | /* We test the old body (obody) contents to avoid tripping | |
1049 | over the under-construction body. */ | |
1050 | for (opno = 0; opno < noutputs; opno++) | |
1051 | if (reg_overlap_mentioned_p (clobbered_reg, output_rtx[opno])) | |
1052 | internal_error ("asm clobber conflict with output operand"); | |
1053 | ||
1054 | for (opno = 0; opno < ninputs - ninout; opno++) | |
1055 | if (reg_overlap_mentioned_p (clobbered_reg, | |
1056 | ASM_OPERANDS_INPUT (obody, opno))) | |
1057 | internal_error ("asm clobber conflict with input operand"); | |
1058 | } | |
1059 | ||
add87c42 | 1060 | XVECEXP (body, 0, i++) |
3d52d305 | 1061 | = gen_rtx_CLOBBER (VOIDmode, clobbered_reg); |
9dfbe515 | 1062 | } |
1063 | ||
805e22b2 | 1064 | emit_insn (body); |
9dfbe515 | 1065 | } |
1066 | ||
adc27eec | 1067 | /* For any outputs that needed reloading into registers, spill them |
1068 | back to where they belong. */ | |
1069 | for (i = 0; i < noutputs; ++i) | |
1070 | if (real_output_rtx[i]) | |
1071 | emit_move_insn (real_output_rtx[i], output_rtx[i]); | |
1072 | ||
18d50ae6 | 1073 | crtl->has_asm_statement = 1; |
9dfbe515 | 1074 | free_temp_slots (); |
1075 | } | |
2c7f203c | 1076 | |
4ee9c684 | 1077 | void |
1078 | expand_asm_expr (tree exp) | |
1079 | { | |
1080 | int noutputs, i; | |
1081 | tree outputs, tail; | |
1082 | tree *o; | |
1083 | ||
1084 | if (ASM_INPUT_P (exp)) | |
1085 | { | |
09fb10e8 | 1086 | expand_asm_loc (ASM_STRING (exp), ASM_VOLATILE_P (exp), input_location); |
4ee9c684 | 1087 | return; |
1088 | } | |
1089 | ||
1090 | outputs = ASM_OUTPUTS (exp); | |
1091 | noutputs = list_length (outputs); | |
1092 | /* o[I] is the place that output number I should be written. */ | |
1093 | o = (tree *) alloca (noutputs * sizeof (tree)); | |
1094 | ||
1095 | /* Record the contents of OUTPUTS before it is modified. */ | |
1096 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
1097 | o[i] = TREE_VALUE (tail); | |
1098 | ||
1099 | /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of | |
1100 | OUTPUTS some trees for where the values were actually stored. */ | |
1101 | expand_asm_operands (ASM_STRING (exp), outputs, ASM_INPUTS (exp), | |
1102 | ASM_CLOBBERS (exp), ASM_VOLATILE_P (exp), | |
1103 | input_location); | |
1104 | ||
1105 | /* Copy all the intermediate outputs into the specified outputs. */ | |
1106 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
1107 | { | |
1108 | if (o[i] != TREE_VALUE (tail)) | |
1109 | { | |
5b5037b3 | 1110 | expand_assignment (o[i], TREE_VALUE (tail), false); |
4ee9c684 | 1111 | free_temp_slots (); |
1112 | ||
1113 | /* Restore the original value so that it's correct the next | |
1114 | time we expand this function. */ | |
1115 | TREE_VALUE (tail) = o[i]; | |
1116 | } | |
1117 | } | |
4ee9c684 | 1118 | } |
1119 | ||
2c7f203c | 1120 | /* A subroutine of expand_asm_operands. Check that all operands have |
1121 | the same number of alternatives. Return true if so. */ | |
1122 | ||
1123 | static bool | |
60b8c5b3 | 1124 | check_operand_nalternatives (tree outputs, tree inputs) |
2c7f203c | 1125 | { |
1126 | if (outputs || inputs) | |
1127 | { | |
1128 | tree tmp = TREE_PURPOSE (outputs ? outputs : inputs); | |
1129 | int nalternatives | |
1130 | = n_occurrences (',', TREE_STRING_POINTER (TREE_VALUE (tmp))); | |
1131 | tree next = inputs; | |
1132 | ||
1133 | if (nalternatives + 1 > MAX_RECOG_ALTERNATIVES) | |
1134 | { | |
eb586f2c | 1135 | error ("too many alternatives in %<asm%>"); |
2c7f203c | 1136 | return false; |
1137 | } | |
1138 | ||
1139 | tmp = outputs; | |
1140 | while (tmp) | |
1141 | { | |
1142 | const char *constraint | |
1143 | = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tmp))); | |
1144 | ||
1145 | if (n_occurrences (',', constraint) != nalternatives) | |
1146 | { | |
eb586f2c | 1147 | error ("operand constraints for %<asm%> differ " |
1148 | "in number of alternatives"); | |
2c7f203c | 1149 | return false; |
1150 | } | |
1151 | ||
1152 | if (TREE_CHAIN (tmp)) | |
1153 | tmp = TREE_CHAIN (tmp); | |
1154 | else | |
1155 | tmp = next, next = 0; | |
1156 | } | |
1157 | } | |
1158 | ||
1159 | return true; | |
1160 | } | |
1161 | ||
1162 | /* A subroutine of expand_asm_operands. Check that all operand names | |
1163 | are unique. Return true if so. We rely on the fact that these names | |
1164 | are identifiers, and so have been canonicalized by get_identifier, | |
1165 | so all we need are pointer comparisons. */ | |
1166 | ||
1167 | static bool | |
60b8c5b3 | 1168 | check_unique_operand_names (tree outputs, tree inputs) |
2c7f203c | 1169 | { |
1170 | tree i, j; | |
1171 | ||
1172 | for (i = outputs; i ; i = TREE_CHAIN (i)) | |
1173 | { | |
1174 | tree i_name = TREE_PURPOSE (TREE_PURPOSE (i)); | |
1175 | if (! i_name) | |
1176 | continue; | |
1177 | ||
1178 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
e3189f72 | 1179 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
2c7f203c | 1180 | goto failure; |
1181 | } | |
1182 | ||
1183 | for (i = inputs; i ; i = TREE_CHAIN (i)) | |
1184 | { | |
1185 | tree i_name = TREE_PURPOSE (TREE_PURPOSE (i)); | |
1186 | if (! i_name) | |
1187 | continue; | |
1188 | ||
1189 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
e3189f72 | 1190 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
2c7f203c | 1191 | goto failure; |
1192 | for (j = outputs; j ; j = TREE_CHAIN (j)) | |
e3189f72 | 1193 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
2c7f203c | 1194 | goto failure; |
1195 | } | |
1196 | ||
1197 | return true; | |
1198 | ||
1199 | failure: | |
eb586f2c | 1200 | error ("duplicate asm operand name %qs", |
e3189f72 | 1201 | TREE_STRING_POINTER (TREE_PURPOSE (TREE_PURPOSE (i)))); |
2c7f203c | 1202 | return false; |
1203 | } | |
1204 | ||
1205 | /* A subroutine of expand_asm_operands. Resolve the names of the operands | |
1206 | in *POUTPUTS and *PINPUTS to numbers, and replace the name expansions in | |
1207 | STRING and in the constraints to those numbers. */ | |
1208 | ||
ef13e68f | 1209 | tree |
1210 | resolve_asm_operand_names (tree string, tree outputs, tree inputs) | |
2c7f203c | 1211 | { |
ef13e68f | 1212 | char *buffer; |
2c7f203c | 1213 | char *p; |
957697db | 1214 | const char *c; |
2c7f203c | 1215 | tree t; |
1216 | ||
d7e38994 | 1217 | check_unique_operand_names (outputs, inputs); |
1218 | ||
ef13e68f | 1219 | /* Substitute [<name>] in input constraint strings. There should be no |
1220 | named operands in output constraints. */ | |
1221 | for (t = inputs; t ; t = TREE_CHAIN (t)) | |
1222 | { | |
957697db | 1223 | c = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); |
ef13e68f | 1224 | if (strchr (c, '[') != NULL) |
1225 | { | |
1226 | p = buffer = xstrdup (c); | |
1227 | while ((p = strchr (p, '[')) != NULL) | |
1228 | p = resolve_operand_name_1 (p, outputs, inputs); | |
1229 | TREE_VALUE (TREE_PURPOSE (t)) | |
1230 | = build_string (strlen (buffer), buffer); | |
1231 | free (buffer); | |
1232 | } | |
1233 | } | |
1234 | ||
957697db | 1235 | /* Now check for any needed substitutions in the template. */ |
1236 | c = TREE_STRING_POINTER (string); | |
1237 | while ((c = strchr (c, '%')) != NULL) | |
2c7f203c | 1238 | { |
957697db | 1239 | if (c[1] == '[') |
1240 | break; | |
1241 | else if (ISALPHA (c[1]) && c[2] == '[') | |
1242 | break; | |
f9477390 | 1243 | else |
1244 | { | |
957697db | 1245 | c += 1; |
f9477390 | 1246 | continue; |
1247 | } | |
2c7f203c | 1248 | } |
1249 | ||
957697db | 1250 | if (c) |
1251 | { | |
1252 | /* OK, we need to make a copy so we can perform the substitutions. | |
1253 | Assume that we will not need extra space--we get to remove '[' | |
1254 | and ']', which means we cannot have a problem until we have more | |
1255 | than 999 operands. */ | |
1256 | buffer = xstrdup (TREE_STRING_POINTER (string)); | |
1257 | p = buffer + (c - TREE_STRING_POINTER (string)); | |
491e04ef | 1258 | |
957697db | 1259 | while ((p = strchr (p, '%')) != NULL) |
1260 | { | |
1261 | if (p[1] == '[') | |
1262 | p += 1; | |
1263 | else if (ISALPHA (p[1]) && p[2] == '[') | |
1264 | p += 2; | |
1265 | else | |
1266 | { | |
1267 | p += 1; | |
1268 | continue; | |
1269 | } | |
1270 | ||
1271 | p = resolve_operand_name_1 (p, outputs, inputs); | |
1272 | } | |
1273 | ||
1274 | string = build_string (strlen (buffer), buffer); | |
1275 | free (buffer); | |
1276 | } | |
2c7f203c | 1277 | |
2c7f203c | 1278 | return string; |
1279 | } | |
1280 | ||
1281 | /* A subroutine of resolve_operand_names. P points to the '[' for a | |
1282 | potential named operand of the form [<name>]. In place, replace | |
40734805 | 1283 | the name and brackets with a number. Return a pointer to the |
2c7f203c | 1284 | balance of the string after substitution. */ |
1285 | ||
1286 | static char * | |
60b8c5b3 | 1287 | resolve_operand_name_1 (char *p, tree outputs, tree inputs) |
2c7f203c | 1288 | { |
1289 | char *q; | |
1290 | int op; | |
1291 | tree t; | |
1292 | size_t len; | |
1293 | ||
1294 | /* Collect the operand name. */ | |
1295 | q = strchr (p, ']'); | |
1296 | if (!q) | |
1297 | { | |
1298 | error ("missing close brace for named operand"); | |
1299 | return strchr (p, '\0'); | |
1300 | } | |
1301 | len = q - p - 1; | |
1302 | ||
1303 | /* Resolve the name to a number. */ | |
1304 | for (op = 0, t = outputs; t ; t = TREE_CHAIN (t), op++) | |
1305 | { | |
e3189f72 | 1306 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1307 | if (name) | |
db4c0bc2 | 1308 | { |
e3189f72 | 1309 | const char *c = TREE_STRING_POINTER (name); |
db4c0bc2 | 1310 | if (strncmp (c, p + 1, len) == 0 && c[len] == '\0') |
1311 | goto found; | |
1312 | } | |
2c7f203c | 1313 | } |
1314 | for (t = inputs; t ; t = TREE_CHAIN (t), op++) | |
1315 | { | |
e3189f72 | 1316 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1317 | if (name) | |
db4c0bc2 | 1318 | { |
e3189f72 | 1319 | const char *c = TREE_STRING_POINTER (name); |
db4c0bc2 | 1320 | if (strncmp (c, p + 1, len) == 0 && c[len] == '\0') |
1321 | goto found; | |
1322 | } | |
2c7f203c | 1323 | } |
1324 | ||
1325 | *q = '\0'; | |
abd3e6b5 | 1326 | error ("undefined named operand %qs", identifier_to_locale (p + 1)); |
2c7f203c | 1327 | op = 0; |
1328 | found: | |
1329 | ||
1330 | /* Replace the name with the number. Unfortunately, not all libraries | |
1331 | get the return value of sprintf correct, so search for the end of the | |
1332 | generated string by hand. */ | |
1333 | sprintf (p, "%d", op); | |
1334 | p = strchr (p, '\0'); | |
1335 | ||
1336 | /* Verify the no extra buffer space assumption. */ | |
04e579b6 | 1337 | gcc_assert (p <= q); |
2c7f203c | 1338 | |
1339 | /* Shift the rest of the buffer down to fill the gap. */ | |
1340 | memmove (p, q + 1, strlen (q + 1) + 1); | |
1341 | ||
1342 | return p; | |
1343 | } | |
9dfbe515 | 1344 | \f |
735f4358 | 1345 | /* Generate RTL to evaluate the expression EXP. */ |
9dfbe515 | 1346 | |
1347 | void | |
60b8c5b3 | 1348 | expand_expr_stmt (tree exp) |
d513ec2f | 1349 | { |
1350 | rtx value; | |
1351 | tree type; | |
fe9740fd | 1352 | |
1db6d067 | 1353 | value = expand_expr (exp, const0_rtx, VOIDmode, EXPAND_NORMAL); |
d513ec2f | 1354 | type = TREE_TYPE (exp); |
9dfbe515 | 1355 | |
1356 | /* If all we do is reference a volatile value in memory, | |
1357 | copy it to a register to be sure it is actually touched. */ | |
e16ceb8e | 1358 | if (value && MEM_P (value) && TREE_THIS_VOLATILE (exp)) |
9dfbe515 | 1359 | { |
d513ec2f | 1360 | if (TYPE_MODE (type) == VOIDmode) |
0baf472d | 1361 | ; |
d513ec2f | 1362 | else if (TYPE_MODE (type) != BLKmode) |
1363 | value = copy_to_reg (value); | |
9dfbe515 | 1364 | else |
9f4911c9 | 1365 | { |
1366 | rtx lab = gen_label_rtx (); | |
67610d42 | 1367 | |
9f4911c9 | 1368 | /* Compare the value with itself to reference it. */ |
d513ec2f | 1369 | emit_cmp_and_jump_insns (value, value, EQ, |
8ec3c5c2 | 1370 | expand_normal (TYPE_SIZE (type)), |
7e69f45b | 1371 | BLKmode, 0, lab); |
9f4911c9 | 1372 | emit_label (lab); |
1373 | } | |
9dfbe515 | 1374 | } |
1375 | ||
735f4358 | 1376 | /* Free any temporaries used to evaluate this expression. */ |
9dfbe515 | 1377 | free_temp_slots (); |
9dfbe515 | 1378 | } |
1379 | ||
1380 | /* Warn if EXP contains any computations whose results are not used. | |
491e04ef | 1381 | Return 1 if a warning is printed; 0 otherwise. LOCUS is the |
c48505a3 | 1382 | (potential) location of the expression. */ |
9dfbe515 | 1383 | |
12ba0afe | 1384 | int |
b7bf20db | 1385 | warn_if_unused_value (const_tree exp, location_t locus) |
9dfbe515 | 1386 | { |
c48505a3 | 1387 | restart: |
1c3d3e7c | 1388 | if (TREE_USED (exp) || TREE_NO_WARNING (exp)) |
9dfbe515 | 1389 | return 0; |
1390 | ||
f60bd4a6 | 1391 | /* Don't warn about void constructs. This includes casting to void, |
1392 | void function calls, and statement expressions with a final cast | |
1393 | to void. */ | |
1394 | if (VOID_TYPE_P (TREE_TYPE (exp))) | |
1395 | return 0; | |
1396 | ||
51a40400 | 1397 | if (EXPR_HAS_LOCATION (exp)) |
1398 | locus = EXPR_LOCATION (exp); | |
c48505a3 | 1399 | |
9dfbe515 | 1400 | switch (TREE_CODE (exp)) |
1401 | { | |
1402 | case PREINCREMENT_EXPR: | |
1403 | case POSTINCREMENT_EXPR: | |
1404 | case PREDECREMENT_EXPR: | |
1405 | case POSTDECREMENT_EXPR: | |
1406 | case MODIFY_EXPR: | |
1407 | case INIT_EXPR: | |
1408 | case TARGET_EXPR: | |
1409 | case CALL_EXPR: | |
45a10898 | 1410 | case TRY_CATCH_EXPR: |
9dfbe515 | 1411 | case WITH_CLEANUP_EXPR: |
1412 | case EXIT_EXPR: | |
7229f9d7 | 1413 | case VA_ARG_EXPR: |
9dfbe515 | 1414 | return 0; |
1415 | ||
1416 | case BIND_EXPR: | |
1417 | /* For a binding, warn if no side effect within it. */ | |
c48505a3 | 1418 | exp = BIND_EXPR_BODY (exp); |
1419 | goto restart; | |
9dfbe515 | 1420 | |
547a8b24 | 1421 | case SAVE_EXPR: |
a1d07e97 | 1422 | case NON_LVALUE_EXPR: |
c48505a3 | 1423 | exp = TREE_OPERAND (exp, 0); |
1424 | goto restart; | |
547a8b24 | 1425 | |
9dfbe515 | 1426 | case TRUTH_ORIF_EXPR: |
1427 | case TRUTH_ANDIF_EXPR: | |
1428 | /* In && or ||, warn if 2nd operand has no side effect. */ | |
c48505a3 | 1429 | exp = TREE_OPERAND (exp, 1); |
1430 | goto restart; | |
9dfbe515 | 1431 | |
1432 | case COMPOUND_EXPR: | |
c48505a3 | 1433 | if (warn_if_unused_value (TREE_OPERAND (exp, 0), locus)) |
9dfbe515 | 1434 | return 1; |
17743085 | 1435 | /* Let people do `(foo (), 0)' without a warning. */ |
1436 | if (TREE_CONSTANT (TREE_OPERAND (exp, 1))) | |
1437 | return 0; | |
c48505a3 | 1438 | exp = TREE_OPERAND (exp, 1); |
1439 | goto restart; | |
9dfbe515 | 1440 | |
1c3d3e7c | 1441 | case COND_EXPR: |
1442 | /* If this is an expression with side effects, don't warn; this | |
1443 | case commonly appears in macro expansions. */ | |
1444 | if (TREE_SIDE_EFFECTS (exp)) | |
9dfbe515 | 1445 | return 0; |
1c3d3e7c | 1446 | goto warn; |
9dfbe515 | 1447 | |
3201915f | 1448 | case INDIRECT_REF: |
1449 | /* Don't warn about automatic dereferencing of references, since | |
1450 | the user cannot control it. */ | |
1451 | if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == REFERENCE_TYPE) | |
c48505a3 | 1452 | { |
1453 | exp = TREE_OPERAND (exp, 0); | |
1454 | goto restart; | |
1455 | } | |
67610d42 | 1456 | /* Fall through. */ |
1457 | ||
9dfbe515 | 1458 | default: |
9f4911c9 | 1459 | /* Referencing a volatile value is a side effect, so don't warn. */ |
ce45a448 | 1460 | if ((DECL_P (exp) || REFERENCE_CLASS_P (exp)) |
9f4911c9 | 1461 | && TREE_THIS_VOLATILE (exp)) |
1462 | return 0; | |
f3c6d29a | 1463 | |
1464 | /* If this is an expression which has no operands, there is no value | |
1465 | to be unused. There are no such language-independent codes, | |
1466 | but front ends may define such. */ | |
c2f47e15 | 1467 | if (EXPRESSION_CLASS_P (exp) && TREE_OPERAND_LENGTH (exp) == 0) |
f3c6d29a | 1468 | return 0; |
1469 | ||
1c3d3e7c | 1470 | warn: |
2006d7dc | 1471 | warning (OPT_Wunused_value, "%Hvalue computed is not used", &locus); |
9dfbe515 | 1472 | return 1; |
1473 | } | |
1474 | } | |
9dfbe515 | 1475 | |
9dfbe515 | 1476 | \f |
1477 | /* Generate RTL to return from the current function, with no value. | |
1478 | (That is, we do not do anything about returning any value.) */ | |
1479 | ||
1480 | void | |
60b8c5b3 | 1481 | expand_null_return (void) |
9dfbe515 | 1482 | { |
67610d42 | 1483 | /* If this function was declared to return a value, but we |
631ef7ce | 1484 | didn't, clobber the return registers so that they are not |
3fb1e43b | 1485 | propagated live to the rest of the function. */ |
2766437e | 1486 | clobber_return_register (); |
9dfbe515 | 1487 | |
6388f9f7 | 1488 | expand_null_return_1 (); |
9dfbe515 | 1489 | } |
1490 | ||
62380d2d | 1491 | /* Generate RTL to return directly from the current function. |
1492 | (That is, we bypass any return value.) */ | |
1493 | ||
1494 | void | |
1495 | expand_naked_return (void) | |
1496 | { | |
6388f9f7 | 1497 | rtx end_label; |
62380d2d | 1498 | |
1499 | clear_pending_stack_adjust (); | |
1500 | do_pending_stack_adjust (); | |
62380d2d | 1501 | |
6388f9f7 | 1502 | end_label = naked_return_label; |
62380d2d | 1503 | if (end_label == 0) |
1504 | end_label = naked_return_label = gen_label_rtx (); | |
6388f9f7 | 1505 | |
1506 | emit_jump (end_label); | |
62380d2d | 1507 | } |
1508 | ||
9dfbe515 | 1509 | /* Generate RTL to return from the current function, with value VAL. */ |
1510 | ||
4098a600 | 1511 | static void |
60b8c5b3 | 1512 | expand_value_return (rtx val) |
9dfbe515 | 1513 | { |
9dfbe515 | 1514 | /* Copy the value to the return location |
1515 | unless it's already there. */ | |
1516 | ||
24049db9 | 1517 | rtx return_reg = DECL_RTL (DECL_RESULT (current_function_decl)); |
9dfbe515 | 1518 | if (return_reg != val) |
d6fe1ae4 | 1519 | { |
d6fe1ae4 | 1520 | tree type = TREE_TYPE (DECL_RESULT (current_function_decl)); |
45550790 | 1521 | if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl))) |
1522 | { | |
78a8ed03 | 1523 | int unsignedp = TYPE_UNSIGNED (type); |
45550790 | 1524 | enum machine_mode old_mode |
1525 | = DECL_MODE (DECL_RESULT (current_function_decl)); | |
1526 | enum machine_mode mode | |
1527 | = promote_mode (type, old_mode, &unsignedp, 1); | |
1528 | ||
1529 | if (mode != old_mode) | |
1530 | val = convert_modes (mode, old_mode, val, unsignedp); | |
1531 | } | |
155b05dc | 1532 | if (GET_CODE (return_reg) == PARALLEL) |
5f4cd670 | 1533 | emit_group_load (return_reg, val, type, int_size_in_bytes (type)); |
155b05dc | 1534 | else |
d6fe1ae4 | 1535 | emit_move_insn (return_reg, val); |
1536 | } | |
155b05dc | 1537 | |
6388f9f7 | 1538 | expand_null_return_1 (); |
9dfbe515 | 1539 | } |
1540 | ||
6388f9f7 | 1541 | /* Output a return with no value. */ |
9dfbe515 | 1542 | |
1543 | static void | |
6388f9f7 | 1544 | expand_null_return_1 (void) |
9dfbe515 | 1545 | { |
9dfbe515 | 1546 | clear_pending_stack_adjust (); |
1547 | do_pending_stack_adjust (); | |
7861133f | 1548 | emit_jump (return_label); |
9dfbe515 | 1549 | } |
1550 | \f | |
1551 | /* Generate RTL to evaluate the expression RETVAL and return it | |
1552 | from the current function. */ | |
1553 | ||
1554 | void | |
60b8c5b3 | 1555 | expand_return (tree retval) |
9dfbe515 | 1556 | { |
0e8e37b2 | 1557 | rtx result_rtl; |
19cb6b50 | 1558 | rtx val = 0; |
9dfbe515 | 1559 | tree retval_rhs; |
9dfbe515 | 1560 | |
1561 | /* If function wants no value, give it none. */ | |
1562 | if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl))) == VOID_TYPE) | |
1563 | { | |
8ec3c5c2 | 1564 | expand_normal (retval); |
9dfbe515 | 1565 | expand_null_return (); |
1566 | return; | |
1567 | } | |
1568 | ||
a6260fc7 | 1569 | if (retval == error_mark_node) |
fb9fa837 | 1570 | { |
1571 | /* Treat this like a return of no value from a function that | |
1572 | returns a value. */ | |
1573 | expand_null_return (); | |
40734805 | 1574 | return; |
fb9fa837 | 1575 | } |
75a70cf9 | 1576 | else if ((TREE_CODE (retval) == MODIFY_EXPR |
6388f9f7 | 1577 | || TREE_CODE (retval) == INIT_EXPR) |
75a70cf9 | 1578 | && TREE_CODE (TREE_OPERAND (retval, 0)) == RESULT_DECL) |
1579 | retval_rhs = TREE_OPERAND (retval, 1); | |
9dfbe515 | 1580 | else |
4ee9c684 | 1581 | retval_rhs = retval; |
9dfbe515 | 1582 | |
0e8e37b2 | 1583 | result_rtl = DECL_RTL (DECL_RESULT (current_function_decl)); |
1584 | ||
6f4df69d | 1585 | /* If we are returning the RESULT_DECL, then the value has already |
1586 | been stored into it, so we don't have to do anything special. */ | |
1587 | if (TREE_CODE (retval_rhs) == RESULT_DECL) | |
1588 | expand_value_return (result_rtl); | |
1589 | ||
7e56e13e | 1590 | /* If the result is an aggregate that is being returned in one (or more) |
1591 | registers, load the registers here. The compiler currently can't handle | |
1592 | copying a BLKmode value into registers. We could put this code in a | |
1593 | more general area (for use by everyone instead of just function | |
1594 | call/return), but until this feature is generally usable it is kept here | |
6388f9f7 | 1595 | (and in expand_call). */ |
7e56e13e | 1596 | |
6f4df69d | 1597 | else if (retval_rhs != 0 |
75a70cf9 | 1598 | && TYPE_MODE (TREE_TYPE (retval_rhs)) == BLKmode |
6f4df69d | 1599 | && REG_P (result_rtl)) |
7e56e13e | 1600 | { |
02e7a332 | 1601 | int i; |
1602 | unsigned HOST_WIDE_INT bitpos, xbitpos; | |
2c8ff1ed | 1603 | unsigned HOST_WIDE_INT padding_correction = 0; |
02e7a332 | 1604 | unsigned HOST_WIDE_INT bytes |
1605 | = int_size_in_bytes (TREE_TYPE (retval_rhs)); | |
7e56e13e | 1606 | int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD; |
02e7a332 | 1607 | unsigned int bitsize |
1608 | = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs)), BITS_PER_WORD); | |
f7f3687c | 1609 | rtx *result_pseudos = XALLOCAVEC (rtx, n_regs); |
b1924c4b | 1610 | rtx result_reg, src = NULL_RTX, dst = NULL_RTX; |
8ec3c5c2 | 1611 | rtx result_val = expand_normal (retval_rhs); |
e82ca248 | 1612 | enum machine_mode tmpmode, result_reg_mode; |
7e56e13e | 1613 | |
cc119c14 | 1614 | if (bytes == 0) |
1615 | { | |
1616 | expand_null_return (); | |
1617 | return; | |
1618 | } | |
1619 | ||
2c8ff1ed | 1620 | /* If the structure doesn't take up a whole number of words, see |
1621 | whether the register value should be padded on the left or on | |
1622 | the right. Set PADDING_CORRECTION to the number of padding | |
1623 | bits needed on the left side. | |
1624 | ||
1625 | In most ABIs, the structure will be returned at the least end of | |
1626 | the register, which translates to right padding on little-endian | |
1627 | targets and left padding on big-endian targets. The opposite | |
1628 | holds if the structure is returned at the most significant | |
1629 | end of the register. */ | |
1630 | if (bytes % UNITS_PER_WORD != 0 | |
1631 | && (targetm.calls.return_in_msb (TREE_TYPE (retval_rhs)) | |
1632 | ? !BYTES_BIG_ENDIAN | |
1633 | : BYTES_BIG_ENDIAN)) | |
1634 | padding_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD) | |
1635 | * BITS_PER_UNIT)); | |
f710f2e5 | 1636 | |
67610d42 | 1637 | /* Copy the structure BITSIZE bits at a time. */ |
2c8ff1ed | 1638 | for (bitpos = 0, xbitpos = padding_correction; |
f710f2e5 | 1639 | bitpos < bytes * BITS_PER_UNIT; |
1640 | bitpos += bitsize, xbitpos += bitsize) | |
7e56e13e | 1641 | { |
f710f2e5 | 1642 | /* We need a new destination pseudo each time xbitpos is |
2c8ff1ed | 1643 | on a word boundary and when xbitpos == padding_correction |
f710f2e5 | 1644 | (the first time through). */ |
1645 | if (xbitpos % BITS_PER_WORD == 0 | |
2c8ff1ed | 1646 | || xbitpos == padding_correction) |
7e56e13e | 1647 | { |
f710f2e5 | 1648 | /* Generate an appropriate register. */ |
1649 | dst = gen_reg_rtx (word_mode); | |
1650 | result_pseudos[xbitpos / BITS_PER_WORD] = dst; | |
1651 | ||
65a3eed5 | 1652 | /* Clear the destination before we move anything into it. */ |
1653 | emit_move_insn (dst, CONST0_RTX (GET_MODE (dst))); | |
7e56e13e | 1654 | } |
f710f2e5 | 1655 | |
1656 | /* We need a new source operand each time bitpos is on a word | |
1657 | boundary. */ | |
1658 | if (bitpos % BITS_PER_WORD == 0) | |
1659 | src = operand_subword_force (result_val, | |
1660 | bitpos / BITS_PER_WORD, | |
1661 | BLKmode); | |
1662 | ||
1663 | /* Use bitpos for the source extraction (left justified) and | |
1664 | xbitpos for the destination store (right justified). */ | |
1665 | store_bit_field (dst, bitsize, xbitpos % BITS_PER_WORD, word_mode, | |
1666 | extract_bit_field (src, bitsize, | |
1667 | bitpos % BITS_PER_WORD, 1, | |
1445ea5b | 1668 | NULL_RTX, word_mode, word_mode)); |
7e56e13e | 1669 | } |
1670 | ||
2c8ff1ed | 1671 | tmpmode = GET_MODE (result_rtl); |
1672 | if (tmpmode == BLKmode) | |
1673 | { | |
1674 | /* Find the smallest integer mode large enough to hold the | |
1675 | entire structure and use that mode instead of BLKmode | |
1676 | on the USE insn for the return register. */ | |
1677 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); | |
1678 | tmpmode != VOIDmode; | |
1679 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) | |
1680 | /* Have we found a large enough mode? */ | |
1681 | if (GET_MODE_SIZE (tmpmode) >= bytes) | |
1682 | break; | |
7e56e13e | 1683 | |
04e579b6 | 1684 | /* A suitable mode should have been found. */ |
1685 | gcc_assert (tmpmode != VOIDmode); | |
7e56e13e | 1686 | |
2c8ff1ed | 1687 | PUT_MODE (result_rtl, tmpmode); |
1688 | } | |
6a31fbc7 | 1689 | |
e82ca248 | 1690 | if (GET_MODE_SIZE (tmpmode) < GET_MODE_SIZE (word_mode)) |
1691 | result_reg_mode = word_mode; | |
1692 | else | |
1693 | result_reg_mode = tmpmode; | |
1694 | result_reg = gen_reg_rtx (result_reg_mode); | |
1695 | ||
6a31fbc7 | 1696 | for (i = 0; i < n_regs; i++) |
e82ca248 | 1697 | emit_move_insn (operand_subword (result_reg, i, 0, result_reg_mode), |
6a31fbc7 | 1698 | result_pseudos[i]); |
7e56e13e | 1699 | |
e82ca248 | 1700 | if (tmpmode != result_reg_mode) |
1701 | result_reg = gen_lowpart (tmpmode, result_reg); | |
1702 | ||
7e56e13e | 1703 | expand_value_return (result_reg); |
1704 | } | |
28fac5c2 | 1705 | else if (retval_rhs != 0 |
1706 | && !VOID_TYPE_P (TREE_TYPE (retval_rhs)) | |
8ad4c111 | 1707 | && (REG_P (result_rtl) |
28fac5c2 | 1708 | || (GET_CODE (result_rtl) == PARALLEL))) |
9dfbe515 | 1709 | { |
155b05dc | 1710 | /* Calculate the return value into a temporary (usually a pseudo |
1711 | reg). */ | |
387bc205 | 1712 | tree ot = TREE_TYPE (DECL_RESULT (current_function_decl)); |
1713 | tree nt = build_qualified_type (ot, TYPE_QUALS (ot) | TYPE_QUAL_CONST); | |
1714 | ||
1715 | val = assign_temp (nt, 0, 0, 1); | |
1db6d067 | 1716 | val = expand_expr (retval_rhs, val, GET_MODE (val), EXPAND_NORMAL); |
97c87eea | 1717 | val = force_not_mem (val); |
6388f9f7 | 1718 | /* Return the calculated value. */ |
05d18e8b | 1719 | expand_value_return (val); |
9dfbe515 | 1720 | } |
1721 | else | |
1722 | { | |
6388f9f7 | 1723 | /* No hard reg used; calculate value into hard return reg. */ |
1db6d067 | 1724 | expand_expr (retval, const0_rtx, VOIDmode, EXPAND_NORMAL); |
155b05dc | 1725 | expand_value_return (result_rtl); |
9dfbe515 | 1726 | } |
1727 | } | |
9dfbe515 | 1728 | \f |
0deb06c7 | 1729 | /* Emit code to restore vital registers at the beginning of a nonlocal goto |
1730 | handler. */ | |
1731 | static void | |
60b8c5b3 | 1732 | expand_nl_goto_receiver (void) |
0deb06c7 | 1733 | { |
4ee9c684 | 1734 | /* Clobber the FP when we get here, so we have to make sure it's |
66891732 | 1735 | marked as used by this function. */ |
18b42941 | 1736 | emit_use (hard_frame_pointer_rtx); |
66891732 | 1737 | |
1738 | /* Mark the static chain as clobbered here so life information | |
1739 | doesn't get messed up for it. */ | |
18b42941 | 1740 | emit_clobber (static_chain_rtx); |
66891732 | 1741 | |
0deb06c7 | 1742 | #ifdef HAVE_nonlocal_goto |
1743 | if (! HAVE_nonlocal_goto) | |
1744 | #endif | |
1745 | /* First adjust our frame pointer to its actual value. It was | |
1746 | previously set to the start of the virtual area corresponding to | |
1747 | the stacked variables when we branched here and now needs to be | |
1748 | adjusted to the actual hardware fp value. | |
1749 | ||
1750 | Assignments are to virtual registers are converted by | |
1751 | instantiate_virtual_regs into the corresponding assignment | |
1752 | to the underlying register (fp in this case) that makes | |
1753 | the original assignment true. | |
1754 | So the following insn will actually be | |
1755 | decrementing fp by STARTING_FRAME_OFFSET. */ | |
1756 | emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx); | |
1757 | ||
1758 | #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM | |
1759 | if (fixed_regs[ARG_POINTER_REGNUM]) | |
1760 | { | |
1761 | #ifdef ELIMINABLE_REGS | |
1762 | /* If the argument pointer can be eliminated in favor of the | |
1763 | frame pointer, we don't need to restore it. We assume here | |
1764 | that if such an elimination is present, it can always be used. | |
1765 | This is the case on all known machines; if we don't make this | |
1766 | assumption, we do unnecessary saving on many machines. */ | |
e99c3a1d | 1767 | static const struct elims {const int from, to;} elim_regs[] = ELIMINABLE_REGS; |
0deb06c7 | 1768 | size_t i; |
1769 | ||
3098b2d3 | 1770 | for (i = 0; i < ARRAY_SIZE (elim_regs); i++) |
0deb06c7 | 1771 | if (elim_regs[i].from == ARG_POINTER_REGNUM |
1772 | && elim_regs[i].to == HARD_FRAME_POINTER_REGNUM) | |
1773 | break; | |
1774 | ||
3098b2d3 | 1775 | if (i == ARRAY_SIZE (elim_regs)) |
0deb06c7 | 1776 | #endif |
1777 | { | |
1778 | /* Now restore our arg pointer from the address at which it | |
05927e40 | 1779 | was saved in our stack frame. */ |
27a7a23a | 1780 | emit_move_insn (crtl->args.internal_arg_pointer, |
b079a207 | 1781 | copy_to_reg (get_arg_pointer_save_area ())); |
0deb06c7 | 1782 | } |
1783 | } | |
1784 | #endif | |
1785 | ||
1786 | #ifdef HAVE_nonlocal_goto_receiver | |
1787 | if (HAVE_nonlocal_goto_receiver) | |
1788 | emit_insn (gen_nonlocal_goto_receiver ()); | |
1789 | #endif | |
66891732 | 1790 | |
3072d30e | 1791 | /* We must not allow the code we just generated to be reordered by |
1792 | scheduling. Specifically, the update of the frame pointer must | |
1793 | happen immediately, not later. */ | |
1794 | emit_insn (gen_blockage ()); | |
0deb06c7 | 1795 | } |
9dfbe515 | 1796 | \f |
1797 | /* Generate RTL for the automatic variable declaration DECL. | |
d9450e9f | 1798 | (Other kinds of declarations are simply ignored if seen here.) */ |
9dfbe515 | 1799 | |
1800 | void | |
60b8c5b3 | 1801 | expand_decl (tree decl) |
9dfbe515 | 1802 | { |
649d8da6 | 1803 | tree type; |
1804 | ||
649d8da6 | 1805 | type = TREE_TYPE (decl); |
9dfbe515 | 1806 | |
10b65125 | 1807 | /* For a CONST_DECL, set mode, alignment, and sizes from those of the |
1808 | type in case this node is used in a reference. */ | |
1809 | if (TREE_CODE (decl) == CONST_DECL) | |
1810 | { | |
1811 | DECL_MODE (decl) = TYPE_MODE (type); | |
1812 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
1813 | DECL_SIZE (decl) = TYPE_SIZE (type); | |
1814 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
1815 | return; | |
1816 | } | |
9dfbe515 | 1817 | |
10b65125 | 1818 | /* Otherwise, only automatic variables need any expansion done. Static and |
1819 | external variables, and external functions, will be handled by | |
1820 | `assemble_variable' (called from finish_decl). TYPE_DECL requires | |
1821 | nothing. PARM_DECLs are handled in `assign_parms'. */ | |
9dfbe515 | 1822 | if (TREE_CODE (decl) != VAR_DECL) |
1823 | return; | |
10b65125 | 1824 | |
486a79cd | 1825 | if (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) |
9dfbe515 | 1826 | return; |
1827 | ||
1828 | /* Create the RTL representation for the variable. */ | |
1829 | ||
1830 | if (type == error_mark_node) | |
0e8e37b2 | 1831 | SET_DECL_RTL (decl, gen_rtx_MEM (BLKmode, const0_rtx)); |
387bc205 | 1832 | |
9dfbe515 | 1833 | else if (DECL_SIZE (decl) == 0) |
9dfbe515 | 1834 | { |
4852b829 | 1835 | /* Variable with incomplete type. */ |
d05cd611 | 1836 | rtx x; |
9dfbe515 | 1837 | if (DECL_INITIAL (decl) == 0) |
1838 | /* Error message was already done; now avoid a crash. */ | |
d05cd611 | 1839 | x = gen_rtx_MEM (BLKmode, const0_rtx); |
9dfbe515 | 1840 | else |
1841 | /* An initializer is going to decide the size of this array. | |
1842 | Until we know the size, represent its address with a reg. */ | |
d05cd611 | 1843 | x = gen_rtx_MEM (BLKmode, gen_reg_rtx (Pmode)); |
f7c44134 | 1844 | |
d05cd611 | 1845 | set_mem_attributes (x, decl, 1); |
1846 | SET_DECL_RTL (decl, x); | |
9dfbe515 | 1847 | } |
e8825bb0 | 1848 | else if (use_register_for_decl (decl)) |
9dfbe515 | 1849 | { |
1850 | /* Automatic variable that can go in a register. */ | |
78a8ed03 | 1851 | int unsignedp = TYPE_UNSIGNED (type); |
01ed6270 | 1852 | enum machine_mode reg_mode |
1853 | = promote_mode (type, DECL_MODE (decl), &unsignedp, 0); | |
e4d8e555 | 1854 | |
0e8e37b2 | 1855 | SET_DECL_RTL (decl, gen_reg_rtx (reg_mode)); |
fcdc122e | 1856 | |
7d1e918b | 1857 | /* Note if the object is a user variable. */ |
ef13e68f | 1858 | if (!DECL_ARTIFICIAL (decl)) |
7d1e918b | 1859 | mark_user_reg (DECL_RTL (decl)); |
1860 | ||
9961142a | 1861 | if (POINTER_TYPE_P (type)) |
1862 | mark_reg_pointer (DECL_RTL (decl), | |
1863 | TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); | |
9dfbe515 | 1864 | } |
109029a3 | 1865 | |
4852b829 | 1866 | else |
9dfbe515 | 1867 | { |
9dfbe515 | 1868 | rtx oldaddr = 0; |
1869 | rtx addr; | |
fcdc122e | 1870 | rtx x; |
9dfbe515 | 1871 | |
4852b829 | 1872 | /* Variable-sized decls are dealt with in the gimplifier. */ |
1873 | gcc_assert (TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST); | |
1874 | ||
9dfbe515 | 1875 | /* If we previously made RTL for this decl, it must be an array |
1876 | whose size was determined by the initializer. | |
1877 | The old address was a register; set that register now | |
1878 | to the proper address. */ | |
0e8e37b2 | 1879 | if (DECL_RTL_SET_P (decl)) |
9dfbe515 | 1880 | { |
04e579b6 | 1881 | gcc_assert (MEM_P (DECL_RTL (decl))); |
1882 | gcc_assert (REG_P (XEXP (DECL_RTL (decl), 0))); | |
9dfbe515 | 1883 | oldaddr = XEXP (DECL_RTL (decl), 0); |
1884 | } | |
1885 | ||
9dfbe515 | 1886 | /* Set alignment we actually gave this decl. */ |
1887 | DECL_ALIGN (decl) = (DECL_MODE (decl) == BLKmode ? BIGGEST_ALIGNMENT | |
1888 | : GET_MODE_BITSIZE (DECL_MODE (decl))); | |
aca14577 | 1889 | DECL_USER_ALIGN (decl) = 0; |
9dfbe515 | 1890 | |
567c22a9 | 1891 | x = assign_temp (decl, 1, 1, 1); |
fcdc122e | 1892 | set_mem_attributes (x, decl, 1); |
1893 | SET_DECL_RTL (decl, x); | |
1894 | ||
9dfbe515 | 1895 | if (oldaddr) |
1896 | { | |
1897 | addr = force_operand (XEXP (DECL_RTL (decl), 0), oldaddr); | |
1898 | if (addr != oldaddr) | |
1899 | emit_move_insn (oldaddr, addr); | |
1900 | } | |
9dfbe515 | 1901 | } |
9dfbe515 | 1902 | } |
1903 | \f | |
4ee9c684 | 1904 | /* Emit code to save the current value of stack. */ |
1905 | rtx | |
1906 | expand_stack_save (void) | |
1907 | { | |
1908 | rtx ret = NULL_RTX; | |
1909 | ||
1910 | do_pending_stack_adjust (); | |
1911 | emit_stack_save (SAVE_BLOCK, &ret, NULL_RTX); | |
1912 | return ret; | |
1913 | } | |
1914 | ||
1915 | /* Emit code to restore the current value of stack. */ | |
1916 | void | |
1917 | expand_stack_restore (tree var) | |
1918 | { | |
b71f72d7 | 1919 | rtx sa = expand_normal (var); |
4ee9c684 | 1920 | |
fbf51400 | 1921 | sa = convert_memory_address (Pmode, sa); |
4ee9c684 | 1922 | emit_stack_restore (SAVE_BLOCK, sa, NULL_RTX); |
1923 | } | |
9dfbe515 | 1924 | \f |
fcb807f8 | 1925 | /* Do the insertion of a case label into case_list. The labels are |
1926 | fed to us in descending order from the sorted vector of case labels used | |
2ca392fd | 1927 | in the tree part of the middle end. So the list we construct is |
8bacfa58 | 1928 | sorted in ascending order. The bounds on the case range, LOW and HIGH, |
1929 | are converted to case's index type TYPE. */ | |
33fbacb1 | 1930 | |
8bacfa58 | 1931 | static struct case_node * |
1932 | add_case_node (struct case_node *head, tree type, tree low, tree high, | |
4527a0e8 | 1933 | tree label, alloc_pool case_node_pool) |
33fbacb1 | 1934 | { |
8bacfa58 | 1935 | tree min_value, max_value; |
2ca392fd | 1936 | struct case_node *r; |
33fbacb1 | 1937 | |
8bacfa58 | 1938 | gcc_assert (TREE_CODE (low) == INTEGER_CST); |
1939 | gcc_assert (!high || TREE_CODE (high) == INTEGER_CST); | |
1940 | ||
1941 | min_value = TYPE_MIN_VALUE (type); | |
1942 | max_value = TYPE_MAX_VALUE (type); | |
1943 | ||
225ec6aa | 1944 | /* If there's no HIGH value, then this is not a case range; it's |
1945 | just a simple case label. But that's just a degenerate case | |
2ca392fd | 1946 | range. |
1947 | If the bounds are equal, turn this into the one-value case. */ | |
1948 | if (!high || tree_int_cst_equal (low, high)) | |
8bacfa58 | 1949 | { |
1950 | /* If the simple case value is unreachable, ignore it. */ | |
c97348a7 | 1951 | if ((TREE_CODE (min_value) == INTEGER_CST |
1952 | && tree_int_cst_compare (low, min_value) < 0) | |
1953 | || (TREE_CODE (max_value) == INTEGER_CST | |
1954 | && tree_int_cst_compare (low, max_value) > 0)) | |
8bacfa58 | 1955 | return head; |
1956 | low = fold_convert (type, low); | |
1957 | high = low; | |
1958 | } | |
1959 | else | |
1960 | { | |
1961 | /* If the entire case range is unreachable, ignore it. */ | |
c97348a7 | 1962 | if ((TREE_CODE (min_value) == INTEGER_CST |
1963 | && tree_int_cst_compare (high, min_value) < 0) | |
1964 | || (TREE_CODE (max_value) == INTEGER_CST | |
1965 | && tree_int_cst_compare (low, max_value) > 0)) | |
8bacfa58 | 1966 | return head; |
1967 | ||
1968 | /* If the lower bound is less than the index type's minimum | |
1969 | value, truncate the range bounds. */ | |
c97348a7 | 1970 | if (TREE_CODE (min_value) == INTEGER_CST |
1971 | && tree_int_cst_compare (low, min_value) < 0) | |
8bacfa58 | 1972 | low = min_value; |
1973 | low = fold_convert (type, low); | |
1974 | ||
1975 | /* If the upper bound is greater than the index type's maximum | |
1976 | value, truncate the range bounds. */ | |
c97348a7 | 1977 | if (TREE_CODE (max_value) == INTEGER_CST |
1978 | && tree_int_cst_compare (high, max_value) > 0) | |
8bacfa58 | 1979 | high = max_value; |
1980 | high = fold_convert (type, high); | |
1981 | } | |
1982 | ||
225ec6aa | 1983 | |
335cf3d5 | 1984 | /* Add this label to the chain. Make sure to drop overflow flags. */ |
4527a0e8 | 1985 | r = (struct case_node *) pool_alloc (case_node_pool); |
335cf3d5 | 1986 | r->low = build_int_cst_wide (TREE_TYPE (low), TREE_INT_CST_LOW (low), |
1987 | TREE_INT_CST_HIGH (low)); | |
1988 | r->high = build_int_cst_wide (TREE_TYPE (high), TREE_INT_CST_LOW (high), | |
1989 | TREE_INT_CST_HIGH (high)); | |
33fbacb1 | 1990 | r->code_label = label; |
2ca392fd | 1991 | r->parent = r->left = NULL; |
fcb807f8 | 1992 | r->right = head; |
1993 | return r; | |
9dfbe515 | 1994 | } |
9dfbe515 | 1995 | \f |
315e4c10 | 1996 | /* Maximum number of case bit tests. */ |
1997 | #define MAX_CASE_BIT_TESTS 3 | |
1998 | ||
1999 | /* By default, enable case bit tests on targets with ashlsi3. */ | |
2000 | #ifndef CASE_USE_BIT_TESTS | |
99bdde56 | 2001 | #define CASE_USE_BIT_TESTS (optab_handler (ashl_optab, word_mode)->insn_code \ |
315e4c10 | 2002 | != CODE_FOR_nothing) |
2003 | #endif | |
2004 | ||
2005 | ||
2006 | /* A case_bit_test represents a set of case nodes that may be | |
2007 | selected from using a bit-wise comparison. HI and LO hold | |
2008 | the integer to be tested against, LABEL contains the label | |
2009 | to jump to upon success and BITS counts the number of case | |
2010 | nodes handled by this test, typically the number of bits | |
2011 | set in HI:LO. */ | |
2012 | ||
2013 | struct case_bit_test | |
2014 | { | |
2015 | HOST_WIDE_INT hi; | |
2016 | HOST_WIDE_INT lo; | |
2017 | rtx label; | |
2018 | int bits; | |
2019 | }; | |
2020 | ||
2021 | /* Determine whether "1 << x" is relatively cheap in word_mode. */ | |
2022 | ||
a046944b | 2023 | static |
2024 | bool lshift_cheap_p (void) | |
315e4c10 | 2025 | { |
2026 | static bool init = false; | |
2027 | static bool cheap = true; | |
2028 | ||
2029 | if (!init) | |
2030 | { | |
2031 | rtx reg = gen_rtx_REG (word_mode, 10000); | |
f529eb25 | 2032 | int cost = rtx_cost (gen_rtx_ASHIFT (word_mode, const1_rtx, reg), SET, |
2033 | optimize_insn_for_speed_p ()); | |
315e4c10 | 2034 | cheap = cost < COSTS_N_INSNS (3); |
2035 | init = true; | |
2036 | } | |
2037 | ||
2038 | return cheap; | |
2039 | } | |
2040 | ||
2041 | /* Comparison function for qsort to order bit tests by decreasing | |
2042 | number of case nodes, i.e. the node with the most cases gets | |
2043 | tested first. */ | |
2044 | ||
b624a250 | 2045 | static int |
2046 | case_bit_test_cmp (const void *p1, const void *p2) | |
315e4c10 | 2047 | { |
f7f3687c | 2048 | const struct case_bit_test *const d1 = (const struct case_bit_test *) p1; |
2049 | const struct case_bit_test *const d2 = (const struct case_bit_test *) p2; | |
315e4c10 | 2050 | |
d2f7f511 | 2051 | if (d2->bits != d1->bits) |
2052 | return d2->bits - d1->bits; | |
2053 | ||
2054 | /* Stabilize the sort. */ | |
2055 | return CODE_LABEL_NUMBER (d2->label) - CODE_LABEL_NUMBER (d1->label); | |
315e4c10 | 2056 | } |
2057 | ||
2058 | /* Expand a switch statement by a short sequence of bit-wise | |
2059 | comparisons. "switch(x)" is effectively converted into | |
2060 | "if ((1 << (x-MINVAL)) & CST)" where CST and MINVAL are | |
2061 | integer constants. | |
2062 | ||
2063 | INDEX_EXPR is the value being switched on, which is of | |
2064 | type INDEX_TYPE. MINVAL is the lowest case value of in | |
2065 | the case nodes, of INDEX_TYPE type, and RANGE is highest | |
2066 | value minus MINVAL, also of type INDEX_TYPE. NODES is | |
2067 | the set of case nodes, and DEFAULT_LABEL is the label to | |
2068 | branch to should none of the cases match. | |
2069 | ||
2070 | There *MUST* be MAX_CASE_BIT_TESTS or less unique case | |
2071 | node targets. */ | |
2072 | ||
2073 | static void | |
60b8c5b3 | 2074 | emit_case_bit_tests (tree index_type, tree index_expr, tree minval, |
2075 | tree range, case_node_ptr nodes, rtx default_label) | |
315e4c10 | 2076 | { |
2077 | struct case_bit_test test[MAX_CASE_BIT_TESTS]; | |
2078 | enum machine_mode mode; | |
2079 | rtx expr, index, label; | |
2080 | unsigned int i,j,lo,hi; | |
2081 | struct case_node *n; | |
2082 | unsigned int count; | |
2083 | ||
2084 | count = 0; | |
2085 | for (n = nodes; n; n = n->right) | |
2086 | { | |
2087 | label = label_rtx (n->code_label); | |
2088 | for (i = 0; i < count; i++) | |
fcb807f8 | 2089 | if (label == test[i].label) |
315e4c10 | 2090 | break; |
2091 | ||
2092 | if (i == count) | |
2093 | { | |
04e579b6 | 2094 | gcc_assert (count < MAX_CASE_BIT_TESTS); |
2095 | test[i].hi = 0; | |
2096 | test[i].lo = 0; | |
315e4c10 | 2097 | test[i].label = label; |
2098 | test[i].bits = 1; | |
2099 | count++; | |
2100 | } | |
2101 | else | |
2102 | test[i].bits++; | |
2103 | ||
faa43f85 | 2104 | lo = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2105 | n->low, minval), 1); | |
2106 | hi = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, | |
2107 | n->high, minval), 1); | |
315e4c10 | 2108 | for (j = lo; j <= hi; j++) |
2109 | if (j >= HOST_BITS_PER_WIDE_INT) | |
2110 | test[i].hi |= (HOST_WIDE_INT) 1 << (j - HOST_BITS_PER_INT); | |
2111 | else | |
2112 | test[i].lo |= (HOST_WIDE_INT) 1 << j; | |
2113 | } | |
2114 | ||
2115 | qsort (test, count, sizeof(*test), case_bit_test_cmp); | |
2116 | ||
faa43f85 | 2117 | index_expr = fold_build2 (MINUS_EXPR, index_type, |
2118 | fold_convert (index_type, index_expr), | |
2119 | fold_convert (index_type, minval)); | |
8ec3c5c2 | 2120 | index = expand_normal (index_expr); |
315e4c10 | 2121 | do_pending_stack_adjust (); |
2122 | ||
2123 | mode = TYPE_MODE (index_type); | |
8ec3c5c2 | 2124 | expr = expand_normal (range); |
72c30859 | 2125 | if (default_label) |
2126 | emit_cmp_and_jump_insns (index, expr, GTU, NULL_RTX, mode, 1, | |
2127 | default_label); | |
315e4c10 | 2128 | |
2129 | index = convert_to_mode (word_mode, index, 0); | |
2130 | index = expand_binop (word_mode, ashl_optab, const1_rtx, | |
2131 | index, NULL_RTX, 1, OPTAB_WIDEN); | |
2132 | ||
2133 | for (i = 0; i < count; i++) | |
2134 | { | |
2135 | expr = immed_double_const (test[i].lo, test[i].hi, word_mode); | |
2136 | expr = expand_binop (word_mode, and_optab, index, expr, | |
2137 | NULL_RTX, 1, OPTAB_WIDEN); | |
2138 | emit_cmp_and_jump_insns (expr, const0_rtx, NE, NULL_RTX, | |
2139 | word_mode, 1, test[i].label); | |
2140 | } | |
2141 | ||
72c30859 | 2142 | if (default_label) |
2143 | emit_jump (default_label); | |
315e4c10 | 2144 | } |
539a3a92 | 2145 | |
bf83534c | 2146 | #ifndef HAVE_casesi |
2147 | #define HAVE_casesi 0 | |
2148 | #endif | |
2149 | ||
2150 | #ifndef HAVE_tablejump | |
2151 | #define HAVE_tablejump 0 | |
2152 | #endif | |
2153 | ||
b655fbd3 | 2154 | /* Terminate a case (Pascal/Ada) or switch (C) statement |
88c06177 | 2155 | in which ORIG_INDEX is the expression to be tested. |
79dc3b8e | 2156 | If ORIG_TYPE is not NULL, it is the original ORIG_INDEX |
2157 | type as given in the source before any compiler conversions. | |
9dfbe515 | 2158 | Generate the code to test it and jump to the right place. */ |
2159 | ||
2160 | void | |
fcb807f8 | 2161 | expand_case (tree exp) |
9dfbe515 | 2162 | { |
374284d3 | 2163 | tree minval = NULL_TREE, maxval = NULL_TREE, range = NULL_TREE; |
9dfbe515 | 2164 | rtx default_label = 0; |
083ec769 | 2165 | struct case_node *n; |
315e4c10 | 2166 | unsigned int count, uniq; |
9dfbe515 | 2167 | rtx index; |
649d8da6 | 2168 | rtx table_label; |
9dfbe515 | 2169 | int ncases; |
2170 | rtx *labelvec; | |
ad4583d9 | 2171 | int i; |
315e4c10 | 2172 | rtx before_case, end, lab; |
649d8da6 | 2173 | |
fcb807f8 | 2174 | tree vec = SWITCH_LABELS (exp); |
2175 | tree orig_type = TREE_TYPE (exp); | |
2176 | tree index_expr = SWITCH_COND (exp); | |
2177 | tree index_type = TREE_TYPE (index_expr); | |
2178 | int unsignedp = TYPE_UNSIGNED (index_type); | |
2179 | ||
2180 | /* The insn after which the case dispatch should finally | |
2181 | be emitted. Zero for a dummy. */ | |
2182 | rtx start; | |
2183 | ||
2184 | /* A list of case labels; it is first built as a list and it may then | |
2185 | be rearranged into a nearly balanced binary tree. */ | |
2186 | struct case_node *case_list = 0; | |
2187 | ||
2188 | /* Label to jump to if no case matches. */ | |
72c30859 | 2189 | tree default_label_decl = NULL_TREE; |
fcb807f8 | 2190 | |
4527a0e8 | 2191 | alloc_pool case_node_pool = create_alloc_pool ("struct case_node pool", |
2192 | sizeof (struct case_node), | |
2193 | 100); | |
2194 | ||
fcb807f8 | 2195 | /* The switch body is lowered in gimplify.c, we should never have |
2196 | switches with a non-NULL SWITCH_BODY here. */ | |
04e579b6 | 2197 | gcc_assert (!SWITCH_BODY (exp)); |
2198 | gcc_assert (SWITCH_LABELS (exp)); | |
e1b37bbb | 2199 | |
9dfbe515 | 2200 | do_pending_stack_adjust (); |
2201 | ||
2202 | /* An ERROR_MARK occurs for various reasons including invalid data type. */ | |
baf56508 | 2203 | if (index_type != error_mark_node) |
9dfbe515 | 2204 | { |
9d6b2687 | 2205 | tree elt; |
083ec769 | 2206 | bitmap label_bitmap; |
72c30859 | 2207 | int vl = TREE_VEC_LENGTH (vec); |
8bacfa58 | 2208 | |
32dc5157 | 2209 | /* cleanup_tree_cfg removes all SWITCH_EXPR with their index |
2210 | expressions being INTEGER_CST. */ | |
2211 | gcc_assert (TREE_CODE (index_expr) != INTEGER_CST); | |
2212 | ||
72c30859 | 2213 | /* The default case, if ever taken, is at the end of TREE_VEC. */ |
2214 | elt = TREE_VEC_ELT (vec, vl - 1); | |
2215 | if (!CASE_LOW (elt) && !CASE_HIGH (elt)) | |
2216 | { | |
2217 | default_label_decl = CASE_LABEL (elt); | |
2218 | --vl; | |
2219 | } | |
9d6b2687 | 2220 | |
72c30859 | 2221 | for (i = vl - 1; i >= 0; --i) |
9d6b2687 | 2222 | { |
b655fbd3 | 2223 | tree low, high; |
9d6b2687 | 2224 | elt = TREE_VEC_ELT (vec, i); |
b655fbd3 | 2225 | |
2226 | low = CASE_LOW (elt); | |
2227 | gcc_assert (low); | |
2228 | high = CASE_HIGH (elt); | |
2229 | ||
2230 | /* Discard empty ranges. */ | |
be813cbd | 2231 | if (high && tree_int_cst_lt (high, low)) |
b655fbd3 | 2232 | continue; |
2233 | ||
2234 | case_list = add_case_node (case_list, index_type, low, high, | |
4527a0e8 | 2235 | CASE_LABEL (elt), case_node_pool); |
8bacfa58 | 2236 | } |
2237 | ||
2238 | ||
1edb3690 | 2239 | before_case = start = get_last_insn (); |
72c30859 | 2240 | if (default_label_decl) |
2241 | default_label = label_rtx (default_label_decl); | |
9dfbe515 | 2242 | |
c5d2e41c | 2243 | /* Get upper and lower bounds of case values. */ |
9dfbe515 | 2244 | |
315e4c10 | 2245 | uniq = 0; |
9dfbe515 | 2246 | count = 0; |
27335ffd | 2247 | label_bitmap = BITMAP_ALLOC (NULL); |
fcb807f8 | 2248 | for (n = case_list; n; n = n->right) |
9dfbe515 | 2249 | { |
9dfbe515 | 2250 | /* Count the elements and track the largest and smallest |
2251 | of them (treating them as signed even if they are not). */ | |
2252 | if (count++ == 0) | |
2253 | { | |
2254 | minval = n->low; | |
2255 | maxval = n->high; | |
2256 | } | |
2257 | else | |
2258 | { | |
be813cbd | 2259 | if (tree_int_cst_lt (n->low, minval)) |
9dfbe515 | 2260 | minval = n->low; |
be813cbd | 2261 | if (tree_int_cst_lt (maxval, n->high)) |
9dfbe515 | 2262 | maxval = n->high; |
2263 | } | |
2264 | /* A range counts double, since it requires two compares. */ | |
2265 | if (! tree_int_cst_equal (n->low, n->high)) | |
2266 | count++; | |
315e4c10 | 2267 | |
083ec769 | 2268 | /* If we have not seen this label yet, then increase the |
2269 | number of unique case node targets seen. */ | |
315e4c10 | 2270 | lab = label_rtx (n->code_label); |
083ec769 | 2271 | if (!bitmap_bit_p (label_bitmap, CODE_LABEL_NUMBER (lab))) |
2272 | { | |
2273 | bitmap_set_bit (label_bitmap, CODE_LABEL_NUMBER (lab)); | |
2274 | uniq++; | |
2275 | } | |
9dfbe515 | 2276 | } |
2277 | ||
27335ffd | 2278 | BITMAP_FREE (label_bitmap); |
083ec769 | 2279 | |
f28dc0d7 | 2280 | /* cleanup_tree_cfg removes all SWITCH_EXPR with a single |
d47a5ab1 | 2281 | destination, such as one with a default case only. However, |
2282 | it doesn't remove cases that are out of range for the switch | |
2283 | type, so we may still get a zero here. */ | |
2284 | if (count == 0) | |
2285 | { | |
72c30859 | 2286 | if (default_label) |
2287 | emit_jump (default_label); | |
4527a0e8 | 2288 | free_alloc_pool (case_node_pool); |
d47a5ab1 | 2289 | return; |
2290 | } | |
9dfbe515 | 2291 | |
f28dc0d7 | 2292 | /* Compute span of values. */ |
faa43f85 | 2293 | range = fold_build2 (MINUS_EXPR, index_type, maxval, minval); |
97fb2bd2 | 2294 | |
315e4c10 | 2295 | /* Try implementing this switch statement by a short sequence of |
2296 | bit-wise comparisons. However, we let the binary-tree case | |
2297 | below handle constant index expressions. */ | |
f28dc0d7 | 2298 | if (CASE_USE_BIT_TESTS |
2299 | && ! TREE_CONSTANT (index_expr) | |
2300 | && compare_tree_int (range, GET_MODE_BITSIZE (word_mode)) < 0 | |
2301 | && compare_tree_int (range, 0) > 0 | |
2302 | && lshift_cheap_p () | |
2303 | && ((uniq == 1 && count >= 3) | |
2304 | || (uniq == 2 && count >= 5) | |
2305 | || (uniq == 3 && count >= 6))) | |
315e4c10 | 2306 | { |
2307 | /* Optimize the case where all the case values fit in a | |
2308 | word without having to subtract MINVAL. In this case, | |
2309 | we can optimize away the subtraction. */ | |
2310 | if (compare_tree_int (minval, 0) > 0 | |
2311 | && compare_tree_int (maxval, GET_MODE_BITSIZE (word_mode)) < 0) | |
2312 | { | |
b4bd9527 | 2313 | minval = build_int_cst (index_type, 0); |
315e4c10 | 2314 | range = maxval; |
2315 | } | |
2316 | emit_case_bit_tests (index_type, index_expr, minval, range, | |
fcb807f8 | 2317 | case_list, default_label); |
315e4c10 | 2318 | } |
2319 | ||
9dfbe515 | 2320 | /* If range of values is much bigger than number of values, |
2321 | make a sequence of conditional branches instead of a dispatch. | |
2322 | If the switch-index is a constant, do it this way | |
2323 | because we can optimize it. */ | |
a608c433 | 2324 | |
906bb5c3 | 2325 | else if (count < targetm.case_values_threshold () |
dc0fc022 | 2326 | || compare_tree_int (range, |
0bfd8d5c | 2327 | (optimize_insn_for_size_p () ? 3 : 10) * count) > 0 |
68ba29ec | 2328 | /* RANGE may be signed, and really large ranges will show up |
2329 | as negative numbers. */ | |
2330 | || compare_tree_int (range, 0) < 0 | |
d39b53a8 | 2331 | #ifndef ASM_OUTPUT_ADDR_DIFF_ELT |
2332 | || flag_pic | |
2333 | #endif | |
51d8e657 | 2334 | || !flag_jump_tables |
bf83534c | 2335 | || TREE_CONSTANT (index_expr) |
2336 | /* If neither casesi or tablejump is available, we can | |
2337 | only go this way. */ | |
2338 | || (!HAVE_casesi && !HAVE_tablejump)) | |
9dfbe515 | 2339 | { |
8ec3c5c2 | 2340 | index = expand_normal (index_expr); |
9dfbe515 | 2341 | |
2342 | /* If the index is a short or char that we do not have | |
2343 | an insn to handle comparisons directly, convert it to | |
2344 | a full integer now, rather than letting each comparison | |
2345 | generate the conversion. */ | |
2346 | ||
2347 | if (GET_MODE_CLASS (GET_MODE (index)) == MODE_INT | |
ad99e708 | 2348 | && ! have_insn_for (COMPARE, GET_MODE (index))) |
9dfbe515 | 2349 | { |
2350 | enum machine_mode wider_mode; | |
2351 | for (wider_mode = GET_MODE (index); wider_mode != VOIDmode; | |
2352 | wider_mode = GET_MODE_WIDER_MODE (wider_mode)) | |
ad99e708 | 2353 | if (have_insn_for (COMPARE, wider_mode)) |
9dfbe515 | 2354 | { |
2355 | index = convert_to_mode (wider_mode, index, unsignedp); | |
2356 | break; | |
2357 | } | |
2358 | } | |
2359 | ||
9dfbe515 | 2360 | do_pending_stack_adjust (); |
2361 | ||
e16ceb8e | 2362 | if (MEM_P (index)) |
9dfbe515 | 2363 | index = copy_to_reg (index); |
9dfbe515 | 2364 | |
cc15f557 | 2365 | /* We generate a binary decision tree to select the |
2366 | appropriate target code. This is done as follows: | |
32dc5157 | 2367 | |
2368 | The list of cases is rearranged into a binary tree, | |
2369 | nearly optimal assuming equal probability for each case. | |
2370 | ||
2371 | The tree is transformed into RTL, eliminating | |
2372 | redundant test conditions at the same time. | |
2373 | ||
2374 | If program flow could reach the end of the | |
2375 | decision tree an unconditional jump to the | |
2376 | default code is emitted. */ | |
2377 | ||
2378 | use_cost_table | |
2379 | = (TREE_CODE (orig_type) != ENUMERAL_TYPE | |
2380 | && estimate_case_costs (case_list)); | |
2381 | balance_case_nodes (&case_list, NULL); | |
2382 | emit_case_nodes (index, case_list, default_label, index_type); | |
72c30859 | 2383 | if (default_label) |
2384 | emit_jump (default_label); | |
9dfbe515 | 2385 | } |
2386 | else | |
2387 | { | |
469b75f7 | 2388 | rtx fallback_label = label_rtx (case_list->code_label); |
427d3c76 | 2389 | table_label = gen_label_rtx (); |
539a3a92 | 2390 | if (! try_casesi (index_type, index_expr, minval, range, |
469b75f7 | 2391 | table_label, default_label, fallback_label)) |
9dfbe515 | 2392 | { |
04e579b6 | 2393 | bool ok; |
81098a4a | 2394 | |
40734805 | 2395 | /* Index jumptables from zero for suitable values of |
81098a4a | 2396 | minval to avoid a subtraction. */ |
0bfd8d5c | 2397 | if (optimize_insn_for_speed_p () |
40734805 | 2398 | && compare_tree_int (minval, 0) > 0 |
2399 | && compare_tree_int (minval, 3) < 0) | |
2400 | { | |
b4bd9527 | 2401 | minval = build_int_cst (index_type, 0); |
40734805 | 2402 | range = maxval; |
2403 | } | |
81098a4a | 2404 | |
04e579b6 | 2405 | ok = try_tablejump (index_type, index_expr, minval, range, |
2406 | table_label, default_label); | |
2407 | gcc_assert (ok); | |
9dfbe515 | 2408 | } |
40734805 | 2409 | |
9dfbe515 | 2410 | /* Get table of labels to jump to, in order of case index. */ |
2411 | ||
81098a4a | 2412 | ncases = tree_low_cst (range, 0) + 1; |
f7f3687c | 2413 | labelvec = XALLOCAVEC (rtx, ncases); |
f0af5a88 | 2414 | memset (labelvec, 0, ncases * sizeof (rtx)); |
9dfbe515 | 2415 | |
fcb807f8 | 2416 | for (n = case_list; n; n = n->right) |
9dfbe515 | 2417 | { |
332fae17 | 2418 | /* Compute the low and high bounds relative to the minimum |
2419 | value since that should fit in a HOST_WIDE_INT while the | |
2420 | actual values may not. */ | |
2421 | HOST_WIDE_INT i_low | |
faa43f85 | 2422 | = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2423 | n->low, minval), 1); | |
332fae17 | 2424 | HOST_WIDE_INT i_high |
faa43f85 | 2425 | = tree_low_cst (fold_build2 (MINUS_EXPR, index_type, |
2426 | n->high, minval), 1); | |
332fae17 | 2427 | HOST_WIDE_INT i; |
2428 | ||
2429 | for (i = i_low; i <= i_high; i ++) | |
2430 | labelvec[i] | |
2431 | = gen_rtx_LABEL_REF (Pmode, label_rtx (n->code_label)); | |
9dfbe515 | 2432 | } |
2433 | ||
469b75f7 | 2434 | /* Fill in the gaps with the default. We may have gaps at |
2435 | the beginning if we tried to avoid the minval subtraction, | |
2436 | so substitute some label even if the default label was | |
2437 | deemed unreachable. */ | |
2438 | if (!default_label) | |
2439 | default_label = fallback_label; | |
2440 | for (i = 0; i < ncases; i++) | |
2441 | if (labelvec[i] == 0) | |
2442 | labelvec[i] = gen_rtx_LABEL_REF (Pmode, default_label); | |
9dfbe515 | 2443 | |
2358393e | 2444 | /* Output the table. */ |
9dfbe515 | 2445 | emit_label (table_label); |
2446 | ||
25d1d1e9 | 2447 | if (CASE_VECTOR_PC_RELATIVE || flag_pic) |
941522d6 | 2448 | emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE, |
2449 | gen_rtx_LABEL_REF (Pmode, table_label), | |
9eaab178 | 2450 | gen_rtvec_v (ncases, labelvec), |
67610d42 | 2451 | const0_rtx, const0_rtx)); |
9dfbe515 | 2452 | else |
941522d6 | 2453 | emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE, |
2454 | gen_rtvec_v (ncases, labelvec))); | |
9dfbe515 | 2455 | |
ac7d3688 | 2456 | /* Record no drop-through after the table. */ |
9dfbe515 | 2457 | emit_barrier (); |
9dfbe515 | 2458 | } |
2459 | ||
3612339f | 2460 | before_case = NEXT_INSN (before_case); |
2461 | end = get_last_insn (); | |
fcb807f8 | 2462 | reorder_insns (before_case, end, start); |
9dfbe515 | 2463 | } |
baf56508 | 2464 | |
9dfbe515 | 2465 | free_temp_slots (); |
4527a0e8 | 2466 | free_alloc_pool (case_node_pool); |
9dfbe515 | 2467 | } |
2468 | ||
85afca2d | 2469 | /* Generate code to jump to LABEL if OP0 and OP1 are equal in mode MODE. */ |
9dfbe515 | 2470 | |
2471 | static void | |
85afca2d | 2472 | do_jump_if_equal (enum machine_mode mode, rtx op0, rtx op1, rtx label, |
2473 | int unsignedp) | |
9dfbe515 | 2474 | { |
85afca2d | 2475 | do_compare_rtx_and_jump (op0, op1, EQ, unsignedp, mode, |
2476 | NULL_RTX, NULL_RTX, label); | |
9dfbe515 | 2477 | } |
2478 | \f | |
2479 | /* Not all case values are encountered equally. This function | |
2480 | uses a heuristic to weight case labels, in cases where that | |
2481 | looks like a reasonable thing to do. | |
2482 | ||
2483 | Right now, all we try to guess is text, and we establish the | |
2484 | following weights: | |
2485 | ||
2486 | chars above space: 16 | |
2487 | digits: 16 | |
2488 | default: 12 | |
2489 | space, punct: 8 | |
2490 | tab: 4 | |
2491 | newline: 2 | |
2492 | other "\" chars: 1 | |
2493 | remaining chars: 0 | |
2494 | ||
2495 | If we find any cases in the switch that are not either -1 or in the range | |
2496 | of valid ASCII characters, or are control characters other than those | |
2497 | commonly used with "\", don't treat this switch scanning text. | |
2498 | ||
2499 | Return 1 if these nodes are suitable for cost estimation, otherwise | |
2500 | return 0. */ | |
2501 | ||
2502 | static int | |
60b8c5b3 | 2503 | estimate_case_costs (case_node_ptr node) |
9dfbe515 | 2504 | { |
c87787ad | 2505 | tree min_ascii = integer_minus_one_node; |
37e8021c | 2506 | tree max_ascii = build_int_cst (TREE_TYPE (node->high), 127); |
9dfbe515 | 2507 | case_node_ptr n; |
2508 | int i; | |
2509 | ||
2510 | /* If we haven't already made the cost table, make it now. Note that the | |
2511 | lower bound of the table is -1, not zero. */ | |
2512 | ||
861cd4f3 | 2513 | if (! cost_table_initialized) |
9dfbe515 | 2514 | { |
861cd4f3 | 2515 | cost_table_initialized = 1; |
9dfbe515 | 2516 | |
2517 | for (i = 0; i < 128; i++) | |
2518 | { | |
cc404a47 | 2519 | if (ISALNUM (i)) |
861cd4f3 | 2520 | COST_TABLE (i) = 16; |
cc404a47 | 2521 | else if (ISPUNCT (i)) |
861cd4f3 | 2522 | COST_TABLE (i) = 8; |
cc404a47 | 2523 | else if (ISCNTRL (i)) |
861cd4f3 | 2524 | COST_TABLE (i) = -1; |
9dfbe515 | 2525 | } |
2526 | ||
861cd4f3 | 2527 | COST_TABLE (' ') = 8; |
2528 | COST_TABLE ('\t') = 4; | |
2529 | COST_TABLE ('\0') = 4; | |
2530 | COST_TABLE ('\n') = 2; | |
2531 | COST_TABLE ('\f') = 1; | |
2532 | COST_TABLE ('\v') = 1; | |
2533 | COST_TABLE ('\b') = 1; | |
9dfbe515 | 2534 | } |
2535 | ||
2536 | /* See if all the case expressions look like text. It is text if the | |
2537 | constant is >= -1 and the highest constant is <= 127. Do all comparisons | |
2538 | as signed arithmetic since we don't want to ever access cost_table with a | |
2539 | value less than -1. Also check that none of the constants in a range | |
2540 | are strange control characters. */ | |
2541 | ||
2542 | for (n = node; n; n = n->right) | |
2543 | { | |
be813cbd | 2544 | if (tree_int_cst_lt (n->low, min_ascii) |
2545 | || tree_int_cst_lt (max_ascii, n->high)) | |
9dfbe515 | 2546 | return 0; |
2547 | ||
a0c2c45b | 2548 | for (i = (HOST_WIDE_INT) TREE_INT_CST_LOW (n->low); |
2549 | i <= (HOST_WIDE_INT) TREE_INT_CST_LOW (n->high); i++) | |
861cd4f3 | 2550 | if (COST_TABLE (i) < 0) |
9dfbe515 | 2551 | return 0; |
2552 | } | |
2553 | ||
2554 | /* All interesting values are within the range of interesting | |
2555 | ASCII characters. */ | |
2556 | return 1; | |
2557 | } | |
2558 | ||
9dfbe515 | 2559 | /* Take an ordered list of case nodes |
2560 | and transform them into a near optimal binary tree, | |
4bbea254 | 2561 | on the assumption that any target code selection value is as |
9dfbe515 | 2562 | likely as any other. |
2563 | ||
2564 | The transformation is performed by splitting the ordered | |
2565 | list into two equal sections plus a pivot. The parts are | |
2566 | then attached to the pivot as left and right branches. Each | |
3398e91d | 2567 | branch is then transformed recursively. */ |
9dfbe515 | 2568 | |
2569 | static void | |
60b8c5b3 | 2570 | balance_case_nodes (case_node_ptr *head, case_node_ptr parent) |
9dfbe515 | 2571 | { |
19cb6b50 | 2572 | case_node_ptr np; |
9dfbe515 | 2573 | |
2574 | np = *head; | |
2575 | if (np) | |
2576 | { | |
2577 | int cost = 0; | |
2578 | int i = 0; | |
2579 | int ranges = 0; | |
19cb6b50 | 2580 | case_node_ptr *npp; |
9dfbe515 | 2581 | case_node_ptr left; |
2582 | ||
2583 | /* Count the number of entries on branch. Also count the ranges. */ | |
2584 | ||
2585 | while (np) | |
2586 | { | |
2587 | if (!tree_int_cst_equal (np->low, np->high)) | |
2588 | { | |
2589 | ranges++; | |
2590 | if (use_cost_table) | |
861cd4f3 | 2591 | cost += COST_TABLE (TREE_INT_CST_LOW (np->high)); |
9dfbe515 | 2592 | } |
2593 | ||
2594 | if (use_cost_table) | |
861cd4f3 | 2595 | cost += COST_TABLE (TREE_INT_CST_LOW (np->low)); |
9dfbe515 | 2596 | |
2597 | i++; | |
2598 | np = np->right; | |
2599 | } | |
2600 | ||
2601 | if (i > 2) | |
2602 | { | |
2603 | /* Split this list if it is long enough for that to help. */ | |
2604 | npp = head; | |
2605 | left = *npp; | |
2606 | if (use_cost_table) | |
2607 | { | |
2608 | /* Find the place in the list that bisects the list's total cost, | |
2609 | Here I gets half the total cost. */ | |
2610 | int n_moved = 0; | |
2611 | i = (cost + 1) / 2; | |
2612 | while (1) | |
2613 | { | |
2614 | /* Skip nodes while their cost does not reach that amount. */ | |
2615 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
861cd4f3 | 2616 | i -= COST_TABLE (TREE_INT_CST_LOW ((*npp)->high)); |
2617 | i -= COST_TABLE (TREE_INT_CST_LOW ((*npp)->low)); | |
9dfbe515 | 2618 | if (i <= 0) |
2619 | break; | |
2620 | npp = &(*npp)->right; | |
2621 | n_moved += 1; | |
2622 | } | |
2623 | if (n_moved == 0) | |
2624 | { | |
2625 | /* Leave this branch lopsided, but optimize left-hand | |
2626 | side and fill in `parent' fields for right-hand side. */ | |
2627 | np = *head; | |
2628 | np->parent = parent; | |
2629 | balance_case_nodes (&np->left, np); | |
2630 | for (; np->right; np = np->right) | |
2631 | np->right->parent = np; | |
2632 | return; | |
2633 | } | |
2634 | } | |
2635 | /* If there are just three nodes, split at the middle one. */ | |
2636 | else if (i == 3) | |
2637 | npp = &(*npp)->right; | |
2638 | else | |
2639 | { | |
2640 | /* Find the place in the list that bisects the list's total cost, | |
2641 | where ranges count as 2. | |
2642 | Here I gets half the total cost. */ | |
2643 | i = (i + ranges + 1) / 2; | |
2644 | while (1) | |
2645 | { | |
2646 | /* Skip nodes while their cost does not reach that amount. */ | |
2647 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
2648 | i--; | |
2649 | i--; | |
2650 | if (i <= 0) | |
2651 | break; | |
2652 | npp = &(*npp)->right; | |
2653 | } | |
2654 | } | |
2655 | *head = np = *npp; | |
2656 | *npp = 0; | |
2657 | np->parent = parent; | |
2658 | np->left = left; | |
2659 | ||
2660 | /* Optimize each of the two split parts. */ | |
2661 | balance_case_nodes (&np->left, np); | |
2662 | balance_case_nodes (&np->right, np); | |
2663 | } | |
2664 | else | |
2665 | { | |
2666 | /* Else leave this branch as one level, | |
2667 | but fill in `parent' fields. */ | |
2668 | np = *head; | |
2669 | np->parent = parent; | |
2670 | for (; np->right; np = np->right) | |
2671 | np->right->parent = np; | |
2672 | } | |
2673 | } | |
2674 | } | |
2675 | \f | |
2676 | /* Search the parent sections of the case node tree | |
2677 | to see if a test for the lower bound of NODE would be redundant. | |
2678 | INDEX_TYPE is the type of the index expression. | |
2679 | ||
2680 | The instructions to generate the case decision tree are | |
2681 | output in the same order as nodes are processed so it is | |
2682 | known that if a parent node checks the range of the current | |
2683 | node minus one that the current node is bounded at its lower | |
2684 | span. Thus the test would be redundant. */ | |
2685 | ||
2686 | static int | |
60b8c5b3 | 2687 | node_has_low_bound (case_node_ptr node, tree index_type) |
9dfbe515 | 2688 | { |
2689 | tree low_minus_one; | |
2690 | case_node_ptr pnode; | |
2691 | ||
2692 | /* If the lower bound of this node is the lowest value in the index type, | |
2693 | we need not test it. */ | |
2694 | ||
2695 | if (tree_int_cst_equal (node->low, TYPE_MIN_VALUE (index_type))) | |
2696 | return 1; | |
2697 | ||
2698 | /* If this node has a left branch, the value at the left must be less | |
2699 | than that at this node, so it cannot be bounded at the bottom and | |
2700 | we need not bother testing any further. */ | |
2701 | ||
2702 | if (node->left) | |
2703 | return 0; | |
2704 | ||
faa43f85 | 2705 | low_minus_one = fold_build2 (MINUS_EXPR, TREE_TYPE (node->low), |
b4bd9527 | 2706 | node->low, |
2707 | build_int_cst (TREE_TYPE (node->low), 1)); | |
9dfbe515 | 2708 | |
2709 | /* If the subtraction above overflowed, we can't verify anything. | |
2710 | Otherwise, look for a parent that tests our value - 1. */ | |
2711 | ||
2712 | if (! tree_int_cst_lt (low_minus_one, node->low)) | |
2713 | return 0; | |
2714 | ||
2715 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
2716 | if (tree_int_cst_equal (low_minus_one, pnode->high)) | |
2717 | return 1; | |
2718 | ||
2719 | return 0; | |
2720 | } | |
2721 | ||
2722 | /* Search the parent sections of the case node tree | |
2723 | to see if a test for the upper bound of NODE would be redundant. | |
2724 | INDEX_TYPE is the type of the index expression. | |
2725 | ||
2726 | The instructions to generate the case decision tree are | |
2727 | output in the same order as nodes are processed so it is | |
2728 | known that if a parent node checks the range of the current | |
2729 | node plus one that the current node is bounded at its upper | |
2730 | span. Thus the test would be redundant. */ | |
2731 | ||
2732 | static int | |
60b8c5b3 | 2733 | node_has_high_bound (case_node_ptr node, tree index_type) |
9dfbe515 | 2734 | { |
2735 | tree high_plus_one; | |
2736 | case_node_ptr pnode; | |
2737 | ||
f52483b5 | 2738 | /* If there is no upper bound, obviously no test is needed. */ |
2739 | ||
2740 | if (TYPE_MAX_VALUE (index_type) == NULL) | |
2741 | return 1; | |
2742 | ||
9dfbe515 | 2743 | /* If the upper bound of this node is the highest value in the type |
2744 | of the index expression, we need not test against it. */ | |
2745 | ||
2746 | if (tree_int_cst_equal (node->high, TYPE_MAX_VALUE (index_type))) | |
2747 | return 1; | |
2748 | ||
2749 | /* If this node has a right branch, the value at the right must be greater | |
2750 | than that at this node, so it cannot be bounded at the top and | |
2751 | we need not bother testing any further. */ | |
2752 | ||
2753 | if (node->right) | |
2754 | return 0; | |
2755 | ||
faa43f85 | 2756 | high_plus_one = fold_build2 (PLUS_EXPR, TREE_TYPE (node->high), |
b4bd9527 | 2757 | node->high, |
2758 | build_int_cst (TREE_TYPE (node->high), 1)); | |
9dfbe515 | 2759 | |
2760 | /* If the addition above overflowed, we can't verify anything. | |
2761 | Otherwise, look for a parent that tests our value + 1. */ | |
2762 | ||
2763 | if (! tree_int_cst_lt (node->high, high_plus_one)) | |
2764 | return 0; | |
2765 | ||
2766 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
2767 | if (tree_int_cst_equal (high_plus_one, pnode->low)) | |
2768 | return 1; | |
2769 | ||
2770 | return 0; | |
2771 | } | |
2772 | ||
2773 | /* Search the parent sections of the | |
2774 | case node tree to see if both tests for the upper and lower | |
2775 | bounds of NODE would be redundant. */ | |
2776 | ||
2777 | static int | |
60b8c5b3 | 2778 | node_is_bounded (case_node_ptr node, tree index_type) |
9dfbe515 | 2779 | { |
2780 | return (node_has_low_bound (node, index_type) | |
2781 | && node_has_high_bound (node, index_type)); | |
2782 | } | |
9dfbe515 | 2783 | \f |
2784 | /* Emit step-by-step code to select a case for the value of INDEX. | |
2785 | The thus generated decision tree follows the form of the | |
2786 | case-node binary tree NODE, whose nodes represent test conditions. | |
2787 | INDEX_TYPE is the type of the index of the switch. | |
2788 | ||
2789 | Care is taken to prune redundant tests from the decision tree | |
2790 | by detecting any boundary conditions already checked by | |
2791 | emitted rtx. (See node_has_high_bound, node_has_low_bound | |
2792 | and node_is_bounded, above.) | |
2793 | ||
2794 | Where the test conditions can be shown to be redundant we emit | |
2795 | an unconditional jump to the target code. As a further | |
2796 | optimization, the subordinates of a tree node are examined to | |
2797 | check for bounded nodes. In this case conditional and/or | |
2798 | unconditional jumps as a result of the boundary check for the | |
2799 | current node are arranged to target the subordinates associated | |
3398e91d | 2800 | code for out of bound conditions on the current node. |
9dfbe515 | 2801 | |
eb2f80f3 | 2802 | We can assume that when control reaches the code generated here, |
9dfbe515 | 2803 | the index value has already been compared with the parents |
2804 | of this node, and determined to be on the same side of each parent | |
2805 | as this node is. Thus, if this node tests for the value 51, | |
2806 | and a parent tested for 52, we don't need to consider | |
2807 | the possibility of a value greater than 51. If another parent | |
2808 | tests for the value 50, then this node need not test anything. */ | |
2809 | ||
2810 | static void | |
60b8c5b3 | 2811 | emit_case_nodes (rtx index, case_node_ptr node, rtx default_label, |
2812 | tree index_type) | |
9dfbe515 | 2813 | { |
2814 | /* If INDEX has an unsigned type, we must make unsigned branches. */ | |
78a8ed03 | 2815 | int unsignedp = TYPE_UNSIGNED (index_type); |
9dfbe515 | 2816 | enum machine_mode mode = GET_MODE (index); |
213b27c9 | 2817 | enum machine_mode imode = TYPE_MODE (index_type); |
9dfbe515 | 2818 | |
a4047043 | 2819 | /* Handle indices detected as constant during RTL expansion. */ |
2820 | if (mode == VOIDmode) | |
2821 | mode = imode; | |
2822 | ||
9dfbe515 | 2823 | /* See if our parents have already tested everything for us. |
2824 | If they have, emit an unconditional jump for this node. */ | |
2825 | if (node_is_bounded (node, index_type)) | |
2826 | emit_jump (label_rtx (node->code_label)); | |
2827 | ||
2828 | else if (tree_int_cst_equal (node->low, node->high)) | |
2829 | { | |
2830 | /* Node is single valued. First see if the index expression matches | |
a92771b8 | 2831 | this node and then check our children, if any. */ |
9dfbe515 | 2832 | |
85afca2d | 2833 | do_jump_if_equal (mode, index, |
213b27c9 | 2834 | convert_modes (mode, imode, |
8ec3c5c2 | 2835 | expand_normal (node->low), |
213b27c9 | 2836 | unsignedp), |
9dfbe515 | 2837 | label_rtx (node->code_label), unsignedp); |
2838 | ||
2839 | if (node->right != 0 && node->left != 0) | |
2840 | { | |
2841 | /* This node has children on both sides. | |
2842 | Dispatch to one side or the other | |
2843 | by comparing the index value with this node's value. | |
2844 | If one subtree is bounded, check that one first, | |
2845 | so we can avoid real branches in the tree. */ | |
2846 | ||
2847 | if (node_is_bounded (node->right, index_type)) | |
2848 | { | |
67610d42 | 2849 | emit_cmp_and_jump_insns (index, |
213b27c9 | 2850 | convert_modes |
2851 | (mode, imode, | |
8ec3c5c2 | 2852 | expand_normal (node->high), |
213b27c9 | 2853 | unsignedp), |
7e69f45b | 2854 | GT, NULL_RTX, mode, unsignedp, |
67610d42 | 2855 | label_rtx (node->right->code_label)); |
9dfbe515 | 2856 | emit_case_nodes (index, node->left, default_label, index_type); |
2857 | } | |
2858 | ||
2859 | else if (node_is_bounded (node->left, index_type)) | |
2860 | { | |
67610d42 | 2861 | emit_cmp_and_jump_insns (index, |
213b27c9 | 2862 | convert_modes |
2863 | (mode, imode, | |
8ec3c5c2 | 2864 | expand_normal (node->high), |
213b27c9 | 2865 | unsignedp), |
7e69f45b | 2866 | LT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 2867 | label_rtx (node->left->code_label)); |
9dfbe515 | 2868 | emit_case_nodes (index, node->right, default_label, index_type); |
2869 | } | |
2870 | ||
84e90d04 | 2871 | /* If both children are single-valued cases with no |
2872 | children, finish up all the work. This way, we can save | |
2873 | one ordered comparison. */ | |
2874 | else if (tree_int_cst_equal (node->right->low, node->right->high) | |
2875 | && node->right->left == 0 | |
2876 | && node->right->right == 0 | |
2877 | && tree_int_cst_equal (node->left->low, node->left->high) | |
2878 | && node->left->left == 0 | |
2879 | && node->left->right == 0) | |
2880 | { | |
2881 | /* Neither node is bounded. First distinguish the two sides; | |
2882 | then emit the code for one side at a time. */ | |
2883 | ||
2884 | /* See if the value matches what the right hand side | |
2885 | wants. */ | |
85afca2d | 2886 | do_jump_if_equal (mode, index, |
84e90d04 | 2887 | convert_modes (mode, imode, |
8ec3c5c2 | 2888 | expand_normal (node->right->low), |
84e90d04 | 2889 | unsignedp), |
2890 | label_rtx (node->right->code_label), | |
2891 | unsignedp); | |
2892 | ||
2893 | /* See if the value matches what the left hand side | |
2894 | wants. */ | |
85afca2d | 2895 | do_jump_if_equal (mode, index, |
84e90d04 | 2896 | convert_modes (mode, imode, |
8ec3c5c2 | 2897 | expand_normal (node->left->low), |
84e90d04 | 2898 | unsignedp), |
2899 | label_rtx (node->left->code_label), | |
2900 | unsignedp); | |
2901 | } | |
2902 | ||
9dfbe515 | 2903 | else |
2904 | { | |
2905 | /* Neither node is bounded. First distinguish the two sides; | |
2906 | then emit the code for one side at a time. */ | |
2907 | ||
67610d42 | 2908 | tree test_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); |
9dfbe515 | 2909 | |
2910 | /* See if the value is on the right. */ | |
67610d42 | 2911 | emit_cmp_and_jump_insns (index, |
213b27c9 | 2912 | convert_modes |
2913 | (mode, imode, | |
8ec3c5c2 | 2914 | expand_normal (node->high), |
213b27c9 | 2915 | unsignedp), |
7e69f45b | 2916 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 2917 | label_rtx (test_label)); |
9dfbe515 | 2918 | |
2919 | /* Value must be on the left. | |
2920 | Handle the left-hand subtree. */ | |
2921 | emit_case_nodes (index, node->left, default_label, index_type); | |
2922 | /* If left-hand subtree does nothing, | |
2923 | go to default. */ | |
72c30859 | 2924 | if (default_label) |
2925 | emit_jump (default_label); | |
9dfbe515 | 2926 | |
2927 | /* Code branches here for the right-hand subtree. */ | |
2928 | expand_label (test_label); | |
2929 | emit_case_nodes (index, node->right, default_label, index_type); | |
2930 | } | |
2931 | } | |
2932 | ||
2933 | else if (node->right != 0 && node->left == 0) | |
2934 | { | |
a33d8949 | 2935 | /* Here we have a right child but no left so we issue a conditional |
9dfbe515 | 2936 | branch to default and process the right child. |
2937 | ||
a33d8949 | 2938 | Omit the conditional branch to default if the right child |
2939 | does not have any children and is single valued; it would | |
2940 | cost too much space to save so little time. */ | |
9dfbe515 | 2941 | |
b60acb0b | 2942 | if (node->right->right || node->right->left |
9dfbe515 | 2943 | || !tree_int_cst_equal (node->right->low, node->right->high)) |
2944 | { | |
2945 | if (!node_has_low_bound (node, index_type)) | |
2946 | { | |
67610d42 | 2947 | emit_cmp_and_jump_insns (index, |
213b27c9 | 2948 | convert_modes |
2949 | (mode, imode, | |
8ec3c5c2 | 2950 | expand_normal (node->high), |
213b27c9 | 2951 | unsignedp), |
7e69f45b | 2952 | LT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 2953 | default_label); |
9dfbe515 | 2954 | } |
2955 | ||
2956 | emit_case_nodes (index, node->right, default_label, index_type); | |
2957 | } | |
2958 | else | |
2959 | /* We cannot process node->right normally | |
2960 | since we haven't ruled out the numbers less than | |
2961 | this node's value. So handle node->right explicitly. */ | |
85afca2d | 2962 | do_jump_if_equal (mode, index, |
213b27c9 | 2963 | convert_modes |
2964 | (mode, imode, | |
8ec3c5c2 | 2965 | expand_normal (node->right->low), |
213b27c9 | 2966 | unsignedp), |
9dfbe515 | 2967 | label_rtx (node->right->code_label), unsignedp); |
2968 | } | |
2969 | ||
2970 | else if (node->right == 0 && node->left != 0) | |
2971 | { | |
2972 | /* Just one subtree, on the left. */ | |
67610d42 | 2973 | if (node->left->left || node->left->right |
9dfbe515 | 2974 | || !tree_int_cst_equal (node->left->low, node->left->high)) |
2975 | { | |
2976 | if (!node_has_high_bound (node, index_type)) | |
2977 | { | |
213b27c9 | 2978 | emit_cmp_and_jump_insns (index, |
2979 | convert_modes | |
2980 | (mode, imode, | |
8ec3c5c2 | 2981 | expand_normal (node->high), |
213b27c9 | 2982 | unsignedp), |
7e69f45b | 2983 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 2984 | default_label); |
9dfbe515 | 2985 | } |
2986 | ||
2987 | emit_case_nodes (index, node->left, default_label, index_type); | |
2988 | } | |
2989 | else | |
2990 | /* We cannot process node->left normally | |
2991 | since we haven't ruled out the numbers less than | |
2992 | this node's value. So handle node->left explicitly. */ | |
85afca2d | 2993 | do_jump_if_equal (mode, index, |
213b27c9 | 2994 | convert_modes |
2995 | (mode, imode, | |
8ec3c5c2 | 2996 | expand_normal (node->left->low), |
213b27c9 | 2997 | unsignedp), |
9dfbe515 | 2998 | label_rtx (node->left->code_label), unsignedp); |
2999 | } | |
3000 | } | |
3001 | else | |
3002 | { | |
3003 | /* Node is a range. These cases are very similar to those for a single | |
3004 | value, except that we do not start by testing whether this node | |
3005 | is the one to branch to. */ | |
3006 | ||
3007 | if (node->right != 0 && node->left != 0) | |
3008 | { | |
3009 | /* Node has subtrees on both sides. | |
3010 | If the right-hand subtree is bounded, | |
3011 | test for it first, since we can go straight there. | |
3012 | Otherwise, we need to make a branch in the control structure, | |
3013 | then handle the two subtrees. */ | |
3014 | tree test_label = 0; | |
3015 | ||
9dfbe515 | 3016 | if (node_is_bounded (node->right, index_type)) |
3017 | /* Right hand node is fully bounded so we can eliminate any | |
3018 | testing and branch directly to the target code. */ | |
213b27c9 | 3019 | emit_cmp_and_jump_insns (index, |
3020 | convert_modes | |
3021 | (mode, imode, | |
8ec3c5c2 | 3022 | expand_normal (node->high), |
213b27c9 | 3023 | unsignedp), |
7e69f45b | 3024 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3025 | label_rtx (node->right->code_label)); |
9dfbe515 | 3026 | else |
3027 | { | |
3028 | /* Right hand node requires testing. | |
3029 | Branch to a label where we will handle it later. */ | |
3030 | ||
3031 | test_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); | |
67610d42 | 3032 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3033 | convert_modes |
3034 | (mode, imode, | |
8ec3c5c2 | 3035 | expand_normal (node->high), |
213b27c9 | 3036 | unsignedp), |
7e69f45b | 3037 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3038 | label_rtx (test_label)); |
9dfbe515 | 3039 | } |
3040 | ||
3041 | /* Value belongs to this node or to the left-hand subtree. */ | |
3042 | ||
213b27c9 | 3043 | emit_cmp_and_jump_insns (index, |
3044 | convert_modes | |
3045 | (mode, imode, | |
8ec3c5c2 | 3046 | expand_normal (node->low), |
213b27c9 | 3047 | unsignedp), |
7e69f45b | 3048 | GE, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3049 | label_rtx (node->code_label)); |
9dfbe515 | 3050 | |
3051 | /* Handle the left-hand subtree. */ | |
3052 | emit_case_nodes (index, node->left, default_label, index_type); | |
3053 | ||
3054 | /* If right node had to be handled later, do that now. */ | |
3055 | ||
3056 | if (test_label) | |
3057 | { | |
3058 | /* If the left-hand subtree fell through, | |
3059 | don't let it fall into the right-hand subtree. */ | |
72c30859 | 3060 | if (default_label) |
3061 | emit_jump (default_label); | |
9dfbe515 | 3062 | |
3063 | expand_label (test_label); | |
3064 | emit_case_nodes (index, node->right, default_label, index_type); | |
3065 | } | |
3066 | } | |
3067 | ||
3068 | else if (node->right != 0 && node->left == 0) | |
3069 | { | |
3070 | /* Deal with values to the left of this node, | |
3071 | if they are possible. */ | |
3072 | if (!node_has_low_bound (node, index_type)) | |
3073 | { | |
67610d42 | 3074 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3075 | convert_modes |
3076 | (mode, imode, | |
8ec3c5c2 | 3077 | expand_normal (node->low), |
213b27c9 | 3078 | unsignedp), |
7e69f45b | 3079 | LT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3080 | default_label); |
9dfbe515 | 3081 | } |
3082 | ||
3083 | /* Value belongs to this node or to the right-hand subtree. */ | |
3084 | ||
213b27c9 | 3085 | emit_cmp_and_jump_insns (index, |
3086 | convert_modes | |
3087 | (mode, imode, | |
8ec3c5c2 | 3088 | expand_normal (node->high), |
213b27c9 | 3089 | unsignedp), |
7e69f45b | 3090 | LE, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3091 | label_rtx (node->code_label)); |
9dfbe515 | 3092 | |
3093 | emit_case_nodes (index, node->right, default_label, index_type); | |
3094 | } | |
3095 | ||
3096 | else if (node->right == 0 && node->left != 0) | |
3097 | { | |
3098 | /* Deal with values to the right of this node, | |
3099 | if they are possible. */ | |
3100 | if (!node_has_high_bound (node, index_type)) | |
3101 | { | |
67610d42 | 3102 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3103 | convert_modes |
3104 | (mode, imode, | |
8ec3c5c2 | 3105 | expand_normal (node->high), |
213b27c9 | 3106 | unsignedp), |
7e69f45b | 3107 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3108 | default_label); |
9dfbe515 | 3109 | } |
3110 | ||
3111 | /* Value belongs to this node or to the left-hand subtree. */ | |
3112 | ||
67610d42 | 3113 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3114 | convert_modes |
3115 | (mode, imode, | |
8ec3c5c2 | 3116 | expand_normal (node->low), |
213b27c9 | 3117 | unsignedp), |
7e69f45b | 3118 | GE, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3119 | label_rtx (node->code_label)); |
9dfbe515 | 3120 | |
3121 | emit_case_nodes (index, node->left, default_label, index_type); | |
3122 | } | |
3123 | ||
3124 | else | |
3125 | { | |
3126 | /* Node has no children so we check low and high bounds to remove | |
3127 | redundant tests. Only one of the bounds can exist, | |
3128 | since otherwise this node is bounded--a case tested already. */ | |
f6664fee | 3129 | int high_bound = node_has_high_bound (node, index_type); |
3130 | int low_bound = node_has_low_bound (node, index_type); | |
9dfbe515 | 3131 | |
f6664fee | 3132 | if (!high_bound && low_bound) |
9dfbe515 | 3133 | { |
67610d42 | 3134 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3135 | convert_modes |
3136 | (mode, imode, | |
8ec3c5c2 | 3137 | expand_normal (node->high), |
213b27c9 | 3138 | unsignedp), |
7e69f45b | 3139 | GT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3140 | default_label); |
9dfbe515 | 3141 | } |
3142 | ||
f6664fee | 3143 | else if (!low_bound && high_bound) |
9dfbe515 | 3144 | { |
67610d42 | 3145 | emit_cmp_and_jump_insns (index, |
213b27c9 | 3146 | convert_modes |
3147 | (mode, imode, | |
8ec3c5c2 | 3148 | expand_normal (node->low), |
213b27c9 | 3149 | unsignedp), |
7e69f45b | 3150 | LT, NULL_RTX, mode, unsignedp, |
5a894bc6 | 3151 | default_label); |
9dfbe515 | 3152 | } |
f6664fee | 3153 | else if (!low_bound && !high_bound) |
3154 | { | |
afa9f587 | 3155 | /* Widen LOW and HIGH to the same width as INDEX. */ |
dc24ddbd | 3156 | tree type = lang_hooks.types.type_for_mode (mode, unsignedp); |
afa9f587 | 3157 | tree low = build1 (CONVERT_EXPR, type, node->low); |
3158 | tree high = build1 (CONVERT_EXPR, type, node->high); | |
ad99e708 | 3159 | rtx low_rtx, new_index, new_bound; |
afa9f587 | 3160 | |
3161 | /* Instead of doing two branches, emit one unsigned branch for | |
3162 | (index-low) > (high-low). */ | |
8ec3c5c2 | 3163 | low_rtx = expand_expr (low, NULL_RTX, mode, EXPAND_NORMAL); |
ad99e708 | 3164 | new_index = expand_simple_binop (mode, MINUS, index, low_rtx, |
3165 | NULL_RTX, unsignedp, | |
3166 | OPTAB_WIDEN); | |
faa43f85 | 3167 | new_bound = expand_expr (fold_build2 (MINUS_EXPR, type, |
3168 | high, low), | |
8ec3c5c2 | 3169 | NULL_RTX, mode, EXPAND_NORMAL); |
40734805 | 3170 | |
afa9f587 | 3171 | emit_cmp_and_jump_insns (new_index, new_bound, GT, NULL_RTX, |
7e69f45b | 3172 | mode, 1, default_label); |
f6664fee | 3173 | } |
9dfbe515 | 3174 | |
3175 | emit_jump (label_rtx (node->code_label)); | |
3176 | } | |
3177 | } | |
3178 | } |