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18ca7dab | 1 | /* Subroutines for manipulating rtx's in semantically interesting ways. |
e5e809f4 | 2 | Copyright (C) 1987, 91, 94-97, 1998 Free Software Foundation, Inc. |
18ca7dab RK |
3 | |
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
940d9d63 RK |
18 | the Free Software Foundation, 59 Temple Place - Suite 330, |
19 | Boston, MA 02111-1307, USA. */ | |
18ca7dab RK |
20 | |
21 | ||
22 | #include "config.h" | |
670ee920 | 23 | #include "system.h" |
18ca7dab RK |
24 | #include "rtl.h" |
25 | #include "tree.h" | |
26 | #include "flags.h" | |
27 | #include "expr.h" | |
28 | #include "hard-reg-set.h" | |
29 | #include "insn-config.h" | |
30 | #include "recog.h" | |
31 | #include "insn-flags.h" | |
32 | #include "insn-codes.h" | |
33 | ||
c795bca9 BS |
34 | #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY |
35 | #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY | |
36 | #endif | |
37 | ||
ea534b63 | 38 | static rtx break_out_memory_refs PROTO((rtx)); |
edff2491 | 39 | static void emit_stack_probe PROTO((rtx)); |
b1ec3c92 CH |
40 | /* Return an rtx for the sum of X and the integer C. |
41 | ||
8008b228 | 42 | This function should be used via the `plus_constant' macro. */ |
18ca7dab RK |
43 | |
44 | rtx | |
b1ec3c92 | 45 | plus_constant_wide (x, c) |
18ca7dab | 46 | register rtx x; |
b1ec3c92 | 47 | register HOST_WIDE_INT c; |
18ca7dab RK |
48 | { |
49 | register RTX_CODE code; | |
50 | register enum machine_mode mode; | |
51 | register rtx tem; | |
52 | int all_constant = 0; | |
53 | ||
54 | if (c == 0) | |
55 | return x; | |
56 | ||
57 | restart: | |
58 | ||
59 | code = GET_CODE (x); | |
60 | mode = GET_MODE (x); | |
61 | switch (code) | |
62 | { | |
63 | case CONST_INT: | |
b1ec3c92 | 64 | return GEN_INT (INTVAL (x) + c); |
18ca7dab RK |
65 | |
66 | case CONST_DOUBLE: | |
67 | { | |
b1ec3c92 CH |
68 | HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x); |
69 | HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x); | |
70 | HOST_WIDE_INT l2 = c; | |
71 | HOST_WIDE_INT h2 = c < 0 ? ~0 : 0; | |
72 | HOST_WIDE_INT lv, hv; | |
18ca7dab RK |
73 | |
74 | add_double (l1, h1, l2, h2, &lv, &hv); | |
75 | ||
76 | return immed_double_const (lv, hv, VOIDmode); | |
77 | } | |
78 | ||
79 | case MEM: | |
80 | /* If this is a reference to the constant pool, try replacing it with | |
81 | a reference to a new constant. If the resulting address isn't | |
82 | valid, don't return it because we have no way to validize it. */ | |
83 | if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF | |
84 | && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0))) | |
85 | { | |
38a448ca RH |
86 | /* Any rtl we create here must go in a saveable obstack, since |
87 | we might have been called from within combine. */ | |
88 | push_obstacks_nochange (); | |
89 | rtl_in_saveable_obstack (); | |
18ca7dab RK |
90 | tem |
91 | = force_const_mem (GET_MODE (x), | |
92 | plus_constant (get_pool_constant (XEXP (x, 0)), | |
93 | c)); | |
38a448ca | 94 | pop_obstacks (); |
18ca7dab RK |
95 | if (memory_address_p (GET_MODE (tem), XEXP (tem, 0))) |
96 | return tem; | |
97 | } | |
98 | break; | |
99 | ||
100 | case CONST: | |
101 | /* If adding to something entirely constant, set a flag | |
102 | so that we can add a CONST around the result. */ | |
103 | x = XEXP (x, 0); | |
104 | all_constant = 1; | |
105 | goto restart; | |
106 | ||
107 | case SYMBOL_REF: | |
108 | case LABEL_REF: | |
109 | all_constant = 1; | |
110 | break; | |
111 | ||
112 | case PLUS: | |
113 | /* The interesting case is adding the integer to a sum. | |
114 | Look for constant term in the sum and combine | |
115 | with C. For an integer constant term, we make a combined | |
116 | integer. For a constant term that is not an explicit integer, | |
e5671f2b RK |
117 | we cannot really combine, but group them together anyway. |
118 | ||
119 | Use a recursive call in case the remaining operand is something | |
120 | that we handle specially, such as a SYMBOL_REF. */ | |
121 | ||
122 | if (GET_CODE (XEXP (x, 1)) == CONST_INT) | |
123 | return plus_constant (XEXP (x, 0), c + INTVAL (XEXP (x, 1))); | |
18ca7dab | 124 | else if (CONSTANT_P (XEXP (x, 0))) |
38a448ca RH |
125 | return gen_rtx_PLUS (mode, |
126 | plus_constant (XEXP (x, 0), c), | |
127 | XEXP (x, 1)); | |
18ca7dab | 128 | else if (CONSTANT_P (XEXP (x, 1))) |
38a448ca RH |
129 | return gen_rtx_PLUS (mode, |
130 | XEXP (x, 0), | |
131 | plus_constant (XEXP (x, 1), c)); | |
132 | break; | |
133 | ||
134 | default: | |
135 | break; | |
18ca7dab RK |
136 | } |
137 | ||
138 | if (c != 0) | |
38a448ca | 139 | x = gen_rtx_PLUS (mode, x, GEN_INT (c)); |
18ca7dab RK |
140 | |
141 | if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF) | |
142 | return x; | |
143 | else if (all_constant) | |
38a448ca | 144 | return gen_rtx_CONST (mode, x); |
18ca7dab RK |
145 | else |
146 | return x; | |
147 | } | |
148 | ||
b1ec3c92 CH |
149 | /* This is the same as `plus_constant', except that it handles LO_SUM. |
150 | ||
151 | This function should be used via the `plus_constant_for_output' macro. */ | |
18ca7dab RK |
152 | |
153 | rtx | |
b1ec3c92 | 154 | plus_constant_for_output_wide (x, c) |
18ca7dab | 155 | register rtx x; |
b1ec3c92 | 156 | register HOST_WIDE_INT c; |
18ca7dab | 157 | { |
18ca7dab | 158 | register enum machine_mode mode = GET_MODE (x); |
18ca7dab RK |
159 | |
160 | if (GET_CODE (x) == LO_SUM) | |
38a448ca | 161 | return gen_rtx_LO_SUM (mode, XEXP (x, 0), |
18ca7dab RK |
162 | plus_constant_for_output (XEXP (x, 1), c)); |
163 | ||
164 | else | |
165 | return plus_constant (x, c); | |
166 | } | |
167 | \f | |
168 | /* If X is a sum, return a new sum like X but lacking any constant terms. | |
169 | Add all the removed constant terms into *CONSTPTR. | |
170 | X itself is not altered. The result != X if and only if | |
171 | it is not isomorphic to X. */ | |
172 | ||
173 | rtx | |
174 | eliminate_constant_term (x, constptr) | |
175 | rtx x; | |
176 | rtx *constptr; | |
177 | { | |
178 | register rtx x0, x1; | |
179 | rtx tem; | |
180 | ||
181 | if (GET_CODE (x) != PLUS) | |
182 | return x; | |
183 | ||
184 | /* First handle constants appearing at this level explicitly. */ | |
185 | if (GET_CODE (XEXP (x, 1)) == CONST_INT | |
186 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr, | |
187 | XEXP (x, 1))) | |
188 | && GET_CODE (tem) == CONST_INT) | |
189 | { | |
190 | *constptr = tem; | |
191 | return eliminate_constant_term (XEXP (x, 0), constptr); | |
192 | } | |
193 | ||
194 | tem = const0_rtx; | |
195 | x0 = eliminate_constant_term (XEXP (x, 0), &tem); | |
196 | x1 = eliminate_constant_term (XEXP (x, 1), &tem); | |
197 | if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0)) | |
198 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), | |
199 | *constptr, tem)) | |
200 | && GET_CODE (tem) == CONST_INT) | |
201 | { | |
202 | *constptr = tem; | |
38a448ca | 203 | return gen_rtx_PLUS (GET_MODE (x), x0, x1); |
18ca7dab RK |
204 | } |
205 | ||
206 | return x; | |
207 | } | |
208 | ||
209 | /* Returns the insn that next references REG after INSN, or 0 | |
210 | if REG is clobbered before next referenced or we cannot find | |
211 | an insn that references REG in a straight-line piece of code. */ | |
212 | ||
213 | rtx | |
214 | find_next_ref (reg, insn) | |
215 | rtx reg; | |
216 | rtx insn; | |
217 | { | |
218 | rtx next; | |
219 | ||
220 | for (insn = NEXT_INSN (insn); insn; insn = next) | |
221 | { | |
222 | next = NEXT_INSN (insn); | |
223 | if (GET_CODE (insn) == NOTE) | |
224 | continue; | |
225 | if (GET_CODE (insn) == CODE_LABEL | |
226 | || GET_CODE (insn) == BARRIER) | |
227 | return 0; | |
228 | if (GET_CODE (insn) == INSN | |
229 | || GET_CODE (insn) == JUMP_INSN | |
230 | || GET_CODE (insn) == CALL_INSN) | |
231 | { | |
232 | if (reg_set_p (reg, insn)) | |
233 | return 0; | |
234 | if (reg_mentioned_p (reg, PATTERN (insn))) | |
235 | return insn; | |
236 | if (GET_CODE (insn) == JUMP_INSN) | |
237 | { | |
238 | if (simplejump_p (insn)) | |
239 | next = JUMP_LABEL (insn); | |
240 | else | |
241 | return 0; | |
242 | } | |
243 | if (GET_CODE (insn) == CALL_INSN | |
244 | && REGNO (reg) < FIRST_PSEUDO_REGISTER | |
245 | && call_used_regs[REGNO (reg)]) | |
246 | return 0; | |
247 | } | |
248 | else | |
249 | abort (); | |
250 | } | |
251 | return 0; | |
252 | } | |
253 | ||
254 | /* Return an rtx for the size in bytes of the value of EXP. */ | |
255 | ||
256 | rtx | |
257 | expr_size (exp) | |
258 | tree exp; | |
259 | { | |
99098c66 RK |
260 | tree size = size_in_bytes (TREE_TYPE (exp)); |
261 | ||
262 | if (TREE_CODE (size) != INTEGER_CST | |
263 | && contains_placeholder_p (size)) | |
264 | size = build (WITH_RECORD_EXPR, sizetype, size, exp); | |
265 | ||
8fbea4dc RK |
266 | return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), |
267 | EXPAND_MEMORY_USE_BAD); | |
18ca7dab RK |
268 | } |
269 | \f | |
270 | /* Return a copy of X in which all memory references | |
271 | and all constants that involve symbol refs | |
272 | have been replaced with new temporary registers. | |
273 | Also emit code to load the memory locations and constants | |
274 | into those registers. | |
275 | ||
276 | If X contains no such constants or memory references, | |
277 | X itself (not a copy) is returned. | |
278 | ||
279 | If a constant is found in the address that is not a legitimate constant | |
280 | in an insn, it is left alone in the hope that it might be valid in the | |
281 | address. | |
282 | ||
283 | X may contain no arithmetic except addition, subtraction and multiplication. | |
284 | Values returned by expand_expr with 1 for sum_ok fit this constraint. */ | |
285 | ||
286 | static rtx | |
287 | break_out_memory_refs (x) | |
288 | register rtx x; | |
289 | { | |
290 | if (GET_CODE (x) == MEM | |
cabeca29 | 291 | || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x) |
18ca7dab | 292 | && GET_MODE (x) != VOIDmode)) |
2cca6e3f | 293 | x = force_reg (GET_MODE (x), x); |
18ca7dab RK |
294 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS |
295 | || GET_CODE (x) == MULT) | |
296 | { | |
297 | register rtx op0 = break_out_memory_refs (XEXP (x, 0)); | |
298 | register rtx op1 = break_out_memory_refs (XEXP (x, 1)); | |
2cca6e3f | 299 | |
18ca7dab | 300 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) |
38a448ca | 301 | x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1); |
18ca7dab | 302 | } |
2cca6e3f | 303 | |
18ca7dab RK |
304 | return x; |
305 | } | |
306 | ||
ea534b63 RK |
307 | #ifdef POINTERS_EXTEND_UNSIGNED |
308 | ||
309 | /* Given X, a memory address in ptr_mode, convert it to an address | |
498b529f RK |
310 | in Pmode, or vice versa (TO_MODE says which way). We take advantage of |
311 | the fact that pointers are not allowed to overflow by commuting arithmetic | |
312 | operations over conversions so that address arithmetic insns can be | |
313 | used. */ | |
ea534b63 | 314 | |
498b529f RK |
315 | rtx |
316 | convert_memory_address (to_mode, x) | |
317 | enum machine_mode to_mode; | |
ea534b63 RK |
318 | rtx x; |
319 | { | |
0b04ec8c | 320 | enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode; |
498b529f RK |
321 | rtx temp; |
322 | ||
0b04ec8c RK |
323 | /* Here we handle some special cases. If none of them apply, fall through |
324 | to the default case. */ | |
ea534b63 RK |
325 | switch (GET_CODE (x)) |
326 | { | |
327 | case CONST_INT: | |
328 | case CONST_DOUBLE: | |
498b529f RK |
329 | return x; |
330 | ||
ea534b63 | 331 | case LABEL_REF: |
38a448ca RH |
332 | temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0)); |
333 | LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x); | |
334 | return temp; | |
498b529f | 335 | |
ea534b63 | 336 | case SYMBOL_REF: |
38a448ca | 337 | temp = gen_rtx_SYMBOL_REF (to_mode, XSTR (x, 0)); |
498b529f | 338 | SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x); |
d7dc4377 | 339 | CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x); |
498b529f | 340 | return temp; |
ea534b63 | 341 | |
498b529f | 342 | case CONST: |
38a448ca RH |
343 | return gen_rtx_CONST (to_mode, |
344 | convert_memory_address (to_mode, XEXP (x, 0))); | |
ea534b63 | 345 | |
0b04ec8c RK |
346 | case PLUS: |
347 | case MULT: | |
348 | /* For addition the second operand is a small constant, we can safely | |
38a448ca | 349 | permute the conversion and addition operation. We can always safely |
60725c78 RK |
350 | permute them if we are making the address narrower. In addition, |
351 | always permute the operations if this is a constant. */ | |
0b04ec8c RK |
352 | if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode) |
353 | || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT | |
60725c78 RK |
354 | && (INTVAL (XEXP (x, 1)) + 20000 < 40000 |
355 | || CONSTANT_P (XEXP (x, 0))))) | |
38a448ca RH |
356 | return gen_rtx_fmt_ee (GET_CODE (x), to_mode, |
357 | convert_memory_address (to_mode, XEXP (x, 0)), | |
358 | convert_memory_address (to_mode, XEXP (x, 1))); | |
359 | break; | |
360 | ||
361 | default: | |
362 | break; | |
ea534b63 | 363 | } |
0b04ec8c RK |
364 | |
365 | return convert_modes (to_mode, from_mode, | |
366 | x, POINTERS_EXTEND_UNSIGNED); | |
ea534b63 RK |
367 | } |
368 | #endif | |
369 | ||
18ca7dab RK |
370 | /* Given a memory address or facsimile X, construct a new address, |
371 | currently equivalent, that is stable: future stores won't change it. | |
372 | ||
373 | X must be composed of constants, register and memory references | |
374 | combined with addition, subtraction and multiplication: | |
375 | in other words, just what you can get from expand_expr if sum_ok is 1. | |
376 | ||
377 | Works by making copies of all regs and memory locations used | |
378 | by X and combining them the same way X does. | |
379 | You could also stabilize the reference to this address | |
380 | by copying the address to a register with copy_to_reg; | |
381 | but then you wouldn't get indexed addressing in the reference. */ | |
382 | ||
383 | rtx | |
384 | copy_all_regs (x) | |
385 | register rtx x; | |
386 | { | |
387 | if (GET_CODE (x) == REG) | |
388 | { | |
11c50c5e DE |
389 | if (REGNO (x) != FRAME_POINTER_REGNUM |
390 | #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM | |
391 | && REGNO (x) != HARD_FRAME_POINTER_REGNUM | |
392 | #endif | |
393 | ) | |
18ca7dab RK |
394 | x = copy_to_reg (x); |
395 | } | |
396 | else if (GET_CODE (x) == MEM) | |
397 | x = copy_to_reg (x); | |
398 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS | |
399 | || GET_CODE (x) == MULT) | |
400 | { | |
401 | register rtx op0 = copy_all_regs (XEXP (x, 0)); | |
402 | register rtx op1 = copy_all_regs (XEXP (x, 1)); | |
403 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) | |
38a448ca | 404 | x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1); |
18ca7dab RK |
405 | } |
406 | return x; | |
407 | } | |
408 | \f | |
409 | /* Return something equivalent to X but valid as a memory address | |
410 | for something of mode MODE. When X is not itself valid, this | |
411 | works by copying X or subexpressions of it into registers. */ | |
412 | ||
413 | rtx | |
414 | memory_address (mode, x) | |
415 | enum machine_mode mode; | |
416 | register rtx x; | |
417 | { | |
18b9ca6f | 418 | register rtx oldx = x; |
18ca7dab | 419 | |
38a448ca RH |
420 | if (GET_CODE (x) == ADDRESSOF) |
421 | return x; | |
422 | ||
ea534b63 RK |
423 | #ifdef POINTERS_EXTEND_UNSIGNED |
424 | if (GET_MODE (x) == ptr_mode) | |
498b529f | 425 | x = convert_memory_address (Pmode, x); |
ea534b63 RK |
426 | #endif |
427 | ||
18ca7dab RK |
428 | /* By passing constant addresses thru registers |
429 | we get a chance to cse them. */ | |
cabeca29 | 430 | if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)) |
18b9ca6f | 431 | x = force_reg (Pmode, x); |
18ca7dab RK |
432 | |
433 | /* Accept a QUEUED that refers to a REG | |
434 | even though that isn't a valid address. | |
435 | On attempting to put this in an insn we will call protect_from_queue | |
436 | which will turn it into a REG, which is valid. */ | |
18b9ca6f | 437 | else if (GET_CODE (x) == QUEUED |
18ca7dab | 438 | && GET_CODE (QUEUED_VAR (x)) == REG) |
18b9ca6f | 439 | ; |
18ca7dab RK |
440 | |
441 | /* We get better cse by rejecting indirect addressing at this stage. | |
442 | Let the combiner create indirect addresses where appropriate. | |
443 | For now, generate the code so that the subexpressions useful to share | |
444 | are visible. But not if cse won't be done! */ | |
18b9ca6f | 445 | else |
18ca7dab | 446 | { |
18b9ca6f RK |
447 | if (! cse_not_expected && GET_CODE (x) != REG) |
448 | x = break_out_memory_refs (x); | |
449 | ||
450 | /* At this point, any valid address is accepted. */ | |
451 | GO_IF_LEGITIMATE_ADDRESS (mode, x, win); | |
452 | ||
453 | /* If it was valid before but breaking out memory refs invalidated it, | |
454 | use it the old way. */ | |
455 | if (memory_address_p (mode, oldx)) | |
456 | goto win2; | |
457 | ||
458 | /* Perform machine-dependent transformations on X | |
459 | in certain cases. This is not necessary since the code | |
460 | below can handle all possible cases, but machine-dependent | |
461 | transformations can make better code. */ | |
462 | LEGITIMIZE_ADDRESS (x, oldx, mode, win); | |
463 | ||
464 | /* PLUS and MULT can appear in special ways | |
465 | as the result of attempts to make an address usable for indexing. | |
466 | Usually they are dealt with by calling force_operand, below. | |
467 | But a sum containing constant terms is special | |
468 | if removing them makes the sum a valid address: | |
469 | then we generate that address in a register | |
470 | and index off of it. We do this because it often makes | |
471 | shorter code, and because the addresses thus generated | |
472 | in registers often become common subexpressions. */ | |
473 | if (GET_CODE (x) == PLUS) | |
474 | { | |
475 | rtx constant_term = const0_rtx; | |
476 | rtx y = eliminate_constant_term (x, &constant_term); | |
477 | if (constant_term == const0_rtx | |
478 | || ! memory_address_p (mode, y)) | |
479 | x = force_operand (x, NULL_RTX); | |
480 | else | |
481 | { | |
38a448ca | 482 | y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term); |
18b9ca6f RK |
483 | if (! memory_address_p (mode, y)) |
484 | x = force_operand (x, NULL_RTX); | |
485 | else | |
486 | x = y; | |
487 | } | |
488 | } | |
18ca7dab | 489 | |
e475ed2a | 490 | else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS) |
18b9ca6f | 491 | x = force_operand (x, NULL_RTX); |
18ca7dab | 492 | |
18b9ca6f RK |
493 | /* If we have a register that's an invalid address, |
494 | it must be a hard reg of the wrong class. Copy it to a pseudo. */ | |
495 | else if (GET_CODE (x) == REG) | |
496 | x = copy_to_reg (x); | |
497 | ||
498 | /* Last resort: copy the value to a register, since | |
499 | the register is a valid address. */ | |
500 | else | |
501 | x = force_reg (Pmode, x); | |
502 | ||
503 | goto done; | |
18ca7dab | 504 | |
c02a7fbb RK |
505 | win2: |
506 | x = oldx; | |
507 | win: | |
508 | if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG | |
509 | /* Don't copy an addr via a reg if it is one of our stack slots. */ | |
510 | && ! (GET_CODE (x) == PLUS | |
511 | && (XEXP (x, 0) == virtual_stack_vars_rtx | |
512 | || XEXP (x, 0) == virtual_incoming_args_rtx))) | |
513 | { | |
514 | if (general_operand (x, Pmode)) | |
515 | x = force_reg (Pmode, x); | |
516 | else | |
517 | x = force_operand (x, NULL_RTX); | |
518 | } | |
18ca7dab | 519 | } |
18b9ca6f RK |
520 | |
521 | done: | |
522 | ||
2cca6e3f RK |
523 | /* If we didn't change the address, we are done. Otherwise, mark |
524 | a reg as a pointer if we have REG or REG + CONST_INT. */ | |
525 | if (oldx == x) | |
526 | return x; | |
527 | else if (GET_CODE (x) == REG) | |
305f22b5 | 528 | mark_reg_pointer (x, 1); |
2cca6e3f RK |
529 | else if (GET_CODE (x) == PLUS |
530 | && GET_CODE (XEXP (x, 0)) == REG | |
531 | && GET_CODE (XEXP (x, 1)) == CONST_INT) | |
305f22b5 | 532 | mark_reg_pointer (XEXP (x, 0), 1); |
2cca6e3f | 533 | |
18b9ca6f RK |
534 | /* OLDX may have been the address on a temporary. Update the address |
535 | to indicate that X is now used. */ | |
536 | update_temp_slot_address (oldx, x); | |
537 | ||
18ca7dab RK |
538 | return x; |
539 | } | |
540 | ||
541 | /* Like `memory_address' but pretend `flag_force_addr' is 0. */ | |
542 | ||
543 | rtx | |
544 | memory_address_noforce (mode, x) | |
545 | enum machine_mode mode; | |
546 | rtx x; | |
547 | { | |
548 | int ambient_force_addr = flag_force_addr; | |
549 | rtx val; | |
550 | ||
551 | flag_force_addr = 0; | |
552 | val = memory_address (mode, x); | |
553 | flag_force_addr = ambient_force_addr; | |
554 | return val; | |
555 | } | |
556 | ||
557 | /* Convert a mem ref into one with a valid memory address. | |
558 | Pass through anything else unchanged. */ | |
559 | ||
560 | rtx | |
561 | validize_mem (ref) | |
562 | rtx ref; | |
563 | { | |
564 | if (GET_CODE (ref) != MEM) | |
565 | return ref; | |
566 | if (memory_address_p (GET_MODE (ref), XEXP (ref, 0))) | |
567 | return ref; | |
568 | /* Don't alter REF itself, since that is probably a stack slot. */ | |
569 | return change_address (ref, GET_MODE (ref), XEXP (ref, 0)); | |
570 | } | |
571 | \f | |
572 | /* Return a modified copy of X with its memory address copied | |
573 | into a temporary register to protect it from side effects. | |
574 | If X is not a MEM, it is returned unchanged (and not copied). | |
575 | Perhaps even if it is a MEM, if there is no need to change it. */ | |
576 | ||
577 | rtx | |
578 | stabilize (x) | |
579 | rtx x; | |
580 | { | |
581 | register rtx addr; | |
582 | if (GET_CODE (x) != MEM) | |
583 | return x; | |
584 | addr = XEXP (x, 0); | |
585 | if (rtx_unstable_p (addr)) | |
586 | { | |
587 | rtx temp = copy_all_regs (addr); | |
588 | rtx mem; | |
589 | if (GET_CODE (temp) != REG) | |
590 | temp = copy_to_reg (temp); | |
38a448ca | 591 | mem = gen_rtx_MEM (GET_MODE (x), temp); |
18ca7dab RK |
592 | |
593 | /* Mark returned memref with in_struct if it's in an array or | |
594 | structure. Copy const and volatile from original memref. */ | |
595 | ||
596 | MEM_IN_STRUCT_P (mem) = MEM_IN_STRUCT_P (x) || GET_CODE (addr) == PLUS; | |
597 | RTX_UNCHANGING_P (mem) = RTX_UNCHANGING_P (x); | |
598 | MEM_VOLATILE_P (mem) = MEM_VOLATILE_P (x); | |
41472af8 MM |
599 | |
600 | /* Since the new MEM is just like the old X, it can alias only | |
601 | the things that X could. */ | |
602 | MEM_ALIAS_SET (mem) = MEM_ALIAS_SET (x); | |
603 | ||
18ca7dab RK |
604 | return mem; |
605 | } | |
606 | return x; | |
607 | } | |
608 | \f | |
609 | /* Copy the value or contents of X to a new temp reg and return that reg. */ | |
610 | ||
611 | rtx | |
612 | copy_to_reg (x) | |
613 | rtx x; | |
614 | { | |
615 | register rtx temp = gen_reg_rtx (GET_MODE (x)); | |
616 | ||
617 | /* If not an operand, must be an address with PLUS and MULT so | |
618 | do the computation. */ | |
619 | if (! general_operand (x, VOIDmode)) | |
620 | x = force_operand (x, temp); | |
621 | ||
622 | if (x != temp) | |
623 | emit_move_insn (temp, x); | |
624 | ||
625 | return temp; | |
626 | } | |
627 | ||
628 | /* Like copy_to_reg but always give the new register mode Pmode | |
629 | in case X is a constant. */ | |
630 | ||
631 | rtx | |
632 | copy_addr_to_reg (x) | |
633 | rtx x; | |
634 | { | |
635 | return copy_to_mode_reg (Pmode, x); | |
636 | } | |
637 | ||
638 | /* Like copy_to_reg but always give the new register mode MODE | |
639 | in case X is a constant. */ | |
640 | ||
641 | rtx | |
642 | copy_to_mode_reg (mode, x) | |
643 | enum machine_mode mode; | |
644 | rtx x; | |
645 | { | |
646 | register rtx temp = gen_reg_rtx (mode); | |
647 | ||
648 | /* If not an operand, must be an address with PLUS and MULT so | |
649 | do the computation. */ | |
650 | if (! general_operand (x, VOIDmode)) | |
651 | x = force_operand (x, temp); | |
652 | ||
653 | if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode) | |
654 | abort (); | |
655 | if (x != temp) | |
656 | emit_move_insn (temp, x); | |
657 | return temp; | |
658 | } | |
659 | ||
660 | /* Load X into a register if it is not already one. | |
661 | Use mode MODE for the register. | |
662 | X should be valid for mode MODE, but it may be a constant which | |
663 | is valid for all integer modes; that's why caller must specify MODE. | |
664 | ||
665 | The caller must not alter the value in the register we return, | |
666 | since we mark it as a "constant" register. */ | |
667 | ||
668 | rtx | |
669 | force_reg (mode, x) | |
670 | enum machine_mode mode; | |
671 | rtx x; | |
672 | { | |
62874575 | 673 | register rtx temp, insn, set; |
18ca7dab RK |
674 | |
675 | if (GET_CODE (x) == REG) | |
676 | return x; | |
677 | temp = gen_reg_rtx (mode); | |
678 | insn = emit_move_insn (temp, x); | |
62874575 | 679 | |
18ca7dab | 680 | /* Let optimizers know that TEMP's value never changes |
62874575 RK |
681 | and that X can be substituted for it. Don't get confused |
682 | if INSN set something else (such as a SUBREG of TEMP). */ | |
683 | if (CONSTANT_P (x) | |
684 | && (set = single_set (insn)) != 0 | |
685 | && SET_DEST (set) == temp) | |
18ca7dab | 686 | { |
b1ec3c92 | 687 | rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX); |
18ca7dab RK |
688 | |
689 | if (note) | |
690 | XEXP (note, 0) = x; | |
691 | else | |
38a448ca | 692 | REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn)); |
18ca7dab RK |
693 | } |
694 | return temp; | |
695 | } | |
696 | ||
697 | /* If X is a memory ref, copy its contents to a new temp reg and return | |
698 | that reg. Otherwise, return X. */ | |
699 | ||
700 | rtx | |
701 | force_not_mem (x) | |
702 | rtx x; | |
703 | { | |
704 | register rtx temp; | |
705 | if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode) | |
706 | return x; | |
707 | temp = gen_reg_rtx (GET_MODE (x)); | |
708 | emit_move_insn (temp, x); | |
709 | return temp; | |
710 | } | |
711 | ||
712 | /* Copy X to TARGET (if it's nonzero and a reg) | |
713 | or to a new temp reg and return that reg. | |
714 | MODE is the mode to use for X in case it is a constant. */ | |
715 | ||
716 | rtx | |
717 | copy_to_suggested_reg (x, target, mode) | |
718 | rtx x, target; | |
719 | enum machine_mode mode; | |
720 | { | |
721 | register rtx temp; | |
722 | ||
723 | if (target && GET_CODE (target) == REG) | |
724 | temp = target; | |
725 | else | |
726 | temp = gen_reg_rtx (mode); | |
727 | ||
728 | emit_move_insn (temp, x); | |
729 | return temp; | |
730 | } | |
731 | \f | |
9ff65789 RK |
732 | /* Return the mode to use to store a scalar of TYPE and MODE. |
733 | PUNSIGNEDP points to the signedness of the type and may be adjusted | |
734 | to show what signedness to use on extension operations. | |
735 | ||
736 | FOR_CALL is non-zero if this call is promoting args for a call. */ | |
737 | ||
738 | enum machine_mode | |
739 | promote_mode (type, mode, punsignedp, for_call) | |
740 | tree type; | |
741 | enum machine_mode mode; | |
742 | int *punsignedp; | |
c84e2712 | 743 | int for_call ATTRIBUTE_UNUSED; |
9ff65789 RK |
744 | { |
745 | enum tree_code code = TREE_CODE (type); | |
746 | int unsignedp = *punsignedp; | |
747 | ||
748 | #ifdef PROMOTE_FOR_CALL_ONLY | |
749 | if (! for_call) | |
750 | return mode; | |
751 | #endif | |
752 | ||
753 | switch (code) | |
754 | { | |
755 | #ifdef PROMOTE_MODE | |
756 | case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE: | |
757 | case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE: | |
758 | PROMOTE_MODE (mode, unsignedp, type); | |
759 | break; | |
760 | #endif | |
761 | ||
ea534b63 | 762 | #ifdef POINTERS_EXTEND_UNSIGNED |
56a4c9e2 | 763 | case REFERENCE_TYPE: |
9ff65789 | 764 | case POINTER_TYPE: |
ea534b63 RK |
765 | mode = Pmode; |
766 | unsignedp = POINTERS_EXTEND_UNSIGNED; | |
9ff65789 | 767 | break; |
ea534b63 | 768 | #endif |
38a448ca RH |
769 | |
770 | default: | |
771 | break; | |
9ff65789 RK |
772 | } |
773 | ||
774 | *punsignedp = unsignedp; | |
775 | return mode; | |
776 | } | |
777 | \f | |
18ca7dab RK |
778 | /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes). |
779 | This pops when ADJUST is positive. ADJUST need not be constant. */ | |
780 | ||
781 | void | |
782 | adjust_stack (adjust) | |
783 | rtx adjust; | |
784 | { | |
785 | rtx temp; | |
786 | adjust = protect_from_queue (adjust, 0); | |
787 | ||
788 | if (adjust == const0_rtx) | |
789 | return; | |
790 | ||
791 | temp = expand_binop (Pmode, | |
792 | #ifdef STACK_GROWS_DOWNWARD | |
793 | add_optab, | |
794 | #else | |
795 | sub_optab, | |
796 | #endif | |
797 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, | |
798 | OPTAB_LIB_WIDEN); | |
799 | ||
800 | if (temp != stack_pointer_rtx) | |
801 | emit_move_insn (stack_pointer_rtx, temp); | |
802 | } | |
803 | ||
804 | /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes). | |
805 | This pushes when ADJUST is positive. ADJUST need not be constant. */ | |
806 | ||
807 | void | |
808 | anti_adjust_stack (adjust) | |
809 | rtx adjust; | |
810 | { | |
811 | rtx temp; | |
812 | adjust = protect_from_queue (adjust, 0); | |
813 | ||
814 | if (adjust == const0_rtx) | |
815 | return; | |
816 | ||
817 | temp = expand_binop (Pmode, | |
818 | #ifdef STACK_GROWS_DOWNWARD | |
819 | sub_optab, | |
820 | #else | |
821 | add_optab, | |
822 | #endif | |
823 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, | |
824 | OPTAB_LIB_WIDEN); | |
825 | ||
826 | if (temp != stack_pointer_rtx) | |
827 | emit_move_insn (stack_pointer_rtx, temp); | |
828 | } | |
829 | ||
830 | /* Round the size of a block to be pushed up to the boundary required | |
831 | by this machine. SIZE is the desired size, which need not be constant. */ | |
832 | ||
833 | rtx | |
834 | round_push (size) | |
835 | rtx size; | |
836 | { | |
c795bca9 BS |
837 | #ifdef PREFERRED_STACK_BOUNDARY |
838 | int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; | |
18ca7dab RK |
839 | if (align == 1) |
840 | return size; | |
841 | if (GET_CODE (size) == CONST_INT) | |
842 | { | |
843 | int new = (INTVAL (size) + align - 1) / align * align; | |
844 | if (INTVAL (size) != new) | |
b1ec3c92 | 845 | size = GEN_INT (new); |
18ca7dab RK |
846 | } |
847 | else | |
848 | { | |
5244db05 | 849 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
0f41302f MS |
850 | but we know it can't. So add ourselves and then do |
851 | TRUNC_DIV_EXPR. */ | |
5244db05 RK |
852 | size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1), |
853 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
854 | size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align), | |
b1ec3c92 CH |
855 | NULL_RTX, 1); |
856 | size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1); | |
18ca7dab | 857 | } |
c795bca9 | 858 | #endif /* PREFERRED_STACK_BOUNDARY */ |
18ca7dab RK |
859 | return size; |
860 | } | |
861 | \f | |
59257ff7 RK |
862 | /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer |
863 | to a previously-created save area. If no save area has been allocated, | |
864 | this function will allocate one. If a save area is specified, it | |
865 | must be of the proper mode. | |
866 | ||
867 | The insns are emitted after insn AFTER, if nonzero, otherwise the insns | |
868 | are emitted at the current position. */ | |
869 | ||
870 | void | |
871 | emit_stack_save (save_level, psave, after) | |
872 | enum save_level save_level; | |
873 | rtx *psave; | |
874 | rtx after; | |
875 | { | |
876 | rtx sa = *psave; | |
877 | /* The default is that we use a move insn and save in a Pmode object. */ | |
0ddc9a94 | 878 | rtx (*fcn) PROTO ((rtx, rtx)) = gen_move_insn; |
a260abc9 | 879 | enum machine_mode mode = STACK_SAVEAREA_MODE (save_level); |
59257ff7 RK |
880 | |
881 | /* See if this machine has anything special to do for this kind of save. */ | |
882 | switch (save_level) | |
883 | { | |
884 | #ifdef HAVE_save_stack_block | |
885 | case SAVE_BLOCK: | |
886 | if (HAVE_save_stack_block) | |
a260abc9 | 887 | fcn = gen_save_stack_block; |
59257ff7 RK |
888 | break; |
889 | #endif | |
890 | #ifdef HAVE_save_stack_function | |
891 | case SAVE_FUNCTION: | |
892 | if (HAVE_save_stack_function) | |
a260abc9 | 893 | fcn = gen_save_stack_function; |
59257ff7 RK |
894 | break; |
895 | #endif | |
896 | #ifdef HAVE_save_stack_nonlocal | |
897 | case SAVE_NONLOCAL: | |
898 | if (HAVE_save_stack_nonlocal) | |
a260abc9 | 899 | fcn = gen_save_stack_nonlocal; |
59257ff7 RK |
900 | break; |
901 | #endif | |
38a448ca RH |
902 | default: |
903 | break; | |
59257ff7 RK |
904 | } |
905 | ||
906 | /* If there is no save area and we have to allocate one, do so. Otherwise | |
907 | verify the save area is the proper mode. */ | |
908 | ||
909 | if (sa == 0) | |
910 | { | |
911 | if (mode != VOIDmode) | |
912 | { | |
913 | if (save_level == SAVE_NONLOCAL) | |
914 | *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0); | |
915 | else | |
916 | *psave = sa = gen_reg_rtx (mode); | |
917 | } | |
918 | } | |
919 | else | |
920 | { | |
921 | if (mode == VOIDmode || GET_MODE (sa) != mode) | |
922 | abort (); | |
923 | } | |
924 | ||
925 | if (after) | |
700f6f98 RK |
926 | { |
927 | rtx seq; | |
928 | ||
929 | start_sequence (); | |
5460015d JW |
930 | /* We must validize inside the sequence, to ensure that any instructions |
931 | created by the validize call also get moved to the right place. */ | |
932 | if (sa != 0) | |
933 | sa = validize_mem (sa); | |
d072107f | 934 | emit_insn (fcn (sa, stack_pointer_rtx)); |
700f6f98 RK |
935 | seq = gen_sequence (); |
936 | end_sequence (); | |
937 | emit_insn_after (seq, after); | |
938 | } | |
59257ff7 | 939 | else |
5460015d JW |
940 | { |
941 | if (sa != 0) | |
942 | sa = validize_mem (sa); | |
943 | emit_insn (fcn (sa, stack_pointer_rtx)); | |
944 | } | |
59257ff7 RK |
945 | } |
946 | ||
947 | /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save | |
948 | area made by emit_stack_save. If it is zero, we have nothing to do. | |
949 | ||
950 | Put any emitted insns after insn AFTER, if nonzero, otherwise at | |
951 | current position. */ | |
952 | ||
953 | void | |
954 | emit_stack_restore (save_level, sa, after) | |
955 | enum save_level save_level; | |
956 | rtx after; | |
957 | rtx sa; | |
958 | { | |
959 | /* The default is that we use a move insn. */ | |
0ddc9a94 | 960 | rtx (*fcn) PROTO ((rtx, rtx)) = gen_move_insn; |
59257ff7 RK |
961 | |
962 | /* See if this machine has anything special to do for this kind of save. */ | |
963 | switch (save_level) | |
964 | { | |
965 | #ifdef HAVE_restore_stack_block | |
966 | case SAVE_BLOCK: | |
967 | if (HAVE_restore_stack_block) | |
968 | fcn = gen_restore_stack_block; | |
969 | break; | |
970 | #endif | |
971 | #ifdef HAVE_restore_stack_function | |
972 | case SAVE_FUNCTION: | |
973 | if (HAVE_restore_stack_function) | |
974 | fcn = gen_restore_stack_function; | |
975 | break; | |
976 | #endif | |
977 | #ifdef HAVE_restore_stack_nonlocal | |
59257ff7 RK |
978 | case SAVE_NONLOCAL: |
979 | if (HAVE_restore_stack_nonlocal) | |
980 | fcn = gen_restore_stack_nonlocal; | |
981 | break; | |
982 | #endif | |
38a448ca RH |
983 | default: |
984 | break; | |
59257ff7 RK |
985 | } |
986 | ||
d072107f RK |
987 | if (sa != 0) |
988 | sa = validize_mem (sa); | |
989 | ||
59257ff7 | 990 | if (after) |
700f6f98 RK |
991 | { |
992 | rtx seq; | |
993 | ||
994 | start_sequence (); | |
d072107f | 995 | emit_insn (fcn (stack_pointer_rtx, sa)); |
700f6f98 RK |
996 | seq = gen_sequence (); |
997 | end_sequence (); | |
998 | emit_insn_after (seq, after); | |
999 | } | |
59257ff7 | 1000 | else |
d072107f | 1001 | emit_insn (fcn (stack_pointer_rtx, sa)); |
59257ff7 RK |
1002 | } |
1003 | \f | |
c9ec4f99 DM |
1004 | #ifdef SETJMP_VIA_SAVE_AREA |
1005 | /* Optimize RTL generated by allocate_dynamic_stack_space for targets | |
1006 | where SETJMP_VIA_SAVE_AREA is true. The problem is that on these | |
1007 | platforms, the dynamic stack space used can corrupt the original | |
1008 | frame, thus causing a crash if a longjmp unwinds to it. */ | |
1009 | ||
1010 | void | |
1011 | optimize_save_area_alloca (insns) | |
1012 | rtx insns; | |
1013 | { | |
1014 | rtx insn; | |
1015 | ||
1016 | for (insn = insns; insn; insn = NEXT_INSN(insn)) | |
1017 | { | |
1018 | rtx note; | |
1019 | ||
1020 | if (GET_CODE (insn) != INSN) | |
1021 | continue; | |
1022 | ||
1023 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) | |
1024 | { | |
1025 | if (REG_NOTE_KIND (note) != REG_SAVE_AREA) | |
1026 | continue; | |
1027 | ||
1028 | if (!current_function_calls_setjmp) | |
1029 | { | |
1030 | rtx pat = PATTERN (insn); | |
1031 | ||
1032 | /* If we do not see the note in a pattern matching | |
1033 | these precise characteristics, we did something | |
1034 | entirely wrong in allocate_dynamic_stack_space. | |
1035 | ||
38e01259 | 1036 | Note, one way this could happen is if SETJMP_VIA_SAVE_AREA |
c9ec4f99 DM |
1037 | was defined on a machine where stacks grow towards higher |
1038 | addresses. | |
1039 | ||
1040 | Right now only supported port with stack that grow upward | |
1041 | is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */ | |
1042 | if (GET_CODE (pat) != SET | |
1043 | || SET_DEST (pat) != stack_pointer_rtx | |
1044 | || GET_CODE (SET_SRC (pat)) != MINUS | |
1045 | || XEXP (SET_SRC (pat), 0) != stack_pointer_rtx) | |
1046 | abort (); | |
1047 | ||
1048 | /* This will now be transformed into a (set REG REG) | |
1049 | so we can just blow away all the other notes. */ | |
1050 | XEXP (SET_SRC (pat), 1) = XEXP (note, 0); | |
1051 | REG_NOTES (insn) = NULL_RTX; | |
1052 | } | |
1053 | else | |
1054 | { | |
1055 | /* setjmp was called, we must remove the REG_SAVE_AREA | |
1056 | note so that later passes do not get confused by its | |
1057 | presence. */ | |
1058 | if (note == REG_NOTES (insn)) | |
1059 | { | |
1060 | REG_NOTES (insn) = XEXP (note, 1); | |
1061 | } | |
1062 | else | |
1063 | { | |
1064 | rtx srch; | |
1065 | ||
1066 | for (srch = REG_NOTES (insn); srch; srch = XEXP (srch, 1)) | |
1067 | if (XEXP (srch, 1) == note) | |
1068 | break; | |
1069 | ||
1070 | if (srch == NULL_RTX) | |
1071 | abort(); | |
1072 | ||
1073 | XEXP (srch, 1) = XEXP (note, 1); | |
1074 | } | |
1075 | } | |
1076 | /* Once we've seen the note of interest, we need not look at | |
1077 | the rest of them. */ | |
1078 | break; | |
1079 | } | |
1080 | } | |
1081 | } | |
1082 | #endif /* SETJMP_VIA_SAVE_AREA */ | |
1083 | ||
18ca7dab RK |
1084 | /* Return an rtx representing the address of an area of memory dynamically |
1085 | pushed on the stack. This region of memory is always aligned to | |
1086 | a multiple of BIGGEST_ALIGNMENT. | |
1087 | ||
1088 | Any required stack pointer alignment is preserved. | |
1089 | ||
1090 | SIZE is an rtx representing the size of the area. | |
091ad0b9 RK |
1091 | TARGET is a place in which the address can be placed. |
1092 | ||
1093 | KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */ | |
18ca7dab RK |
1094 | |
1095 | rtx | |
091ad0b9 | 1096 | allocate_dynamic_stack_space (size, target, known_align) |
18ca7dab RK |
1097 | rtx size; |
1098 | rtx target; | |
091ad0b9 | 1099 | int known_align; |
18ca7dab | 1100 | { |
c9ec4f99 DM |
1101 | #ifdef SETJMP_VIA_SAVE_AREA |
1102 | rtx setjmpless_size = NULL_RTX; | |
1103 | #endif | |
1104 | ||
15fc0026 | 1105 | /* If we're asking for zero bytes, it doesn't matter what we point |
9faa82d8 | 1106 | to since we can't dereference it. But return a reasonable |
15fc0026 RK |
1107 | address anyway. */ |
1108 | if (size == const0_rtx) | |
1109 | return virtual_stack_dynamic_rtx; | |
1110 | ||
1111 | /* Otherwise, show we're calling alloca or equivalent. */ | |
1112 | current_function_calls_alloca = 1; | |
1113 | ||
18ca7dab RK |
1114 | /* Ensure the size is in the proper mode. */ |
1115 | if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode) | |
1116 | size = convert_to_mode (Pmode, size, 1); | |
1117 | ||
1118 | /* We will need to ensure that the address we return is aligned to | |
1119 | BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't | |
1120 | always know its final value at this point in the compilation (it | |
1121 | might depend on the size of the outgoing parameter lists, for | |
1122 | example), so we must align the value to be returned in that case. | |
1123 | (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if | |
1124 | STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined). | |
1125 | We must also do an alignment operation on the returned value if | |
1126 | the stack pointer alignment is less strict that BIGGEST_ALIGNMENT. | |
1127 | ||
1128 | If we have to align, we must leave space in SIZE for the hole | |
1129 | that might result from the alignment operation. */ | |
1130 | ||
c795bca9 | 1131 | #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (PREFERRED_STACK_BOUNDARY) |
515a7242 JW |
1132 | #define MUST_ALIGN 1 |
1133 | #else | |
c795bca9 | 1134 | #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT) |
18ca7dab RK |
1135 | #endif |
1136 | ||
515a7242 | 1137 | if (MUST_ALIGN) |
3b998c11 RK |
1138 | { |
1139 | if (GET_CODE (size) == CONST_INT) | |
b1ec3c92 CH |
1140 | size = GEN_INT (INTVAL (size) |
1141 | + (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1)); | |
3b998c11 RK |
1142 | else |
1143 | size = expand_binop (Pmode, add_optab, size, | |
b1ec3c92 CH |
1144 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
1145 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
3b998c11 | 1146 | } |
1d9d04f8 | 1147 | |
18ca7dab RK |
1148 | #ifdef SETJMP_VIA_SAVE_AREA |
1149 | /* If setjmp restores regs from a save area in the stack frame, | |
1150 | avoid clobbering the reg save area. Note that the offset of | |
1151 | virtual_incoming_args_rtx includes the preallocated stack args space. | |
1152 | It would be no problem to clobber that, but it's on the wrong side | |
1153 | of the old save area. */ | |
1154 | { | |
1155 | rtx dynamic_offset | |
1156 | = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx, | |
b1ec3c92 | 1157 | stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN); |
c9ec4f99 DM |
1158 | |
1159 | if (!current_function_calls_setjmp) | |
1160 | { | |
c795bca9 | 1161 | int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; |
c9ec4f99 DM |
1162 | |
1163 | /* See optimize_save_area_alloca to understand what is being | |
1164 | set up here. */ | |
1165 | ||
c795bca9 | 1166 | #if !defined(PREFERRED_STACK_BOUNDARY) || !defined(MUST_ALIGN) || (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT) |
c9ec4f99 DM |
1167 | /* If anyone creates a target with these characteristics, let them |
1168 | know that our optimization cannot work correctly in such a case. */ | |
1169 | abort(); | |
1170 | #endif | |
1171 | ||
1172 | if (GET_CODE (size) == CONST_INT) | |
1173 | { | |
1174 | int new = INTVAL (size) / align * align; | |
1175 | ||
1176 | if (INTVAL (size) != new) | |
1177 | setjmpless_size = GEN_INT (new); | |
1178 | else | |
1179 | setjmpless_size = size; | |
1180 | } | |
1181 | else | |
1182 | { | |
1183 | /* Since we know overflow is not possible, we avoid using | |
1184 | CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */ | |
1185 | setjmpless_size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, | |
1186 | GEN_INT (align), NULL_RTX, 1); | |
1187 | setjmpless_size = expand_mult (Pmode, setjmpless_size, | |
1188 | GEN_INT (align), NULL_RTX, 1); | |
1189 | } | |
1190 | /* Our optimization works based upon being able to perform a simple | |
1191 | transformation of this RTL into a (set REG REG) so make sure things | |
1192 | did in fact end up in a REG. */ | |
1193 | if (!arith_operand (setjmpless_size, Pmode)) | |
1194 | setjmpless_size = force_reg (Pmode, setjmpless_size); | |
1195 | } | |
1196 | ||
18ca7dab | 1197 | size = expand_binop (Pmode, add_optab, size, dynamic_offset, |
b1ec3c92 | 1198 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
18ca7dab RK |
1199 | } |
1200 | #endif /* SETJMP_VIA_SAVE_AREA */ | |
1201 | ||
1202 | /* Round the size to a multiple of the required stack alignment. | |
1203 | Since the stack if presumed to be rounded before this allocation, | |
1204 | this will maintain the required alignment. | |
1205 | ||
1206 | If the stack grows downward, we could save an insn by subtracting | |
1207 | SIZE from the stack pointer and then aligning the stack pointer. | |
1208 | The problem with this is that the stack pointer may be unaligned | |
1209 | between the execution of the subtraction and alignment insns and | |
1210 | some machines do not allow this. Even on those that do, some | |
1211 | signal handlers malfunction if a signal should occur between those | |
1212 | insns. Since this is an extremely rare event, we have no reliable | |
1213 | way of knowing which systems have this problem. So we avoid even | |
1214 | momentarily mis-aligning the stack. */ | |
1215 | ||
c795bca9 | 1216 | #ifdef PREFERRED_STACK_BOUNDARY |
86b25e81 RS |
1217 | /* If we added a variable amount to SIZE, |
1218 | we can no longer assume it is aligned. */ | |
515a7242 | 1219 | #if !defined (SETJMP_VIA_SAVE_AREA) |
c795bca9 | 1220 | if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0) |
34c9156a | 1221 | #endif |
091ad0b9 | 1222 | size = round_push (size); |
89d825c9 | 1223 | #endif |
18ca7dab RK |
1224 | |
1225 | do_pending_stack_adjust (); | |
1226 | ||
edff2491 RK |
1227 | /* If needed, check that we have the required amount of stack. Take into |
1228 | account what has already been checked. */ | |
1229 | if (flag_stack_check && ! STACK_CHECK_BUILTIN) | |
1230 | probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size); | |
1231 | ||
091ad0b9 RK |
1232 | /* Don't use a TARGET that isn't a pseudo. */ |
1233 | if (target == 0 || GET_CODE (target) != REG | |
1234 | || REGNO (target) < FIRST_PSEUDO_REGISTER) | |
18ca7dab RK |
1235 | target = gen_reg_rtx (Pmode); |
1236 | ||
305f22b5 | 1237 | mark_reg_pointer (target, known_align / BITS_PER_UNIT); |
3ad69266 | 1238 | |
18ca7dab RK |
1239 | /* Perform the required allocation from the stack. Some systems do |
1240 | this differently than simply incrementing/decrementing from the | |
38a448ca | 1241 | stack pointer, such as acquiring the space by calling malloc(). */ |
18ca7dab RK |
1242 | #ifdef HAVE_allocate_stack |
1243 | if (HAVE_allocate_stack) | |
1244 | { | |
39403d82 DE |
1245 | enum machine_mode mode = STACK_SIZE_MODE; |
1246 | ||
18ca7dab RK |
1247 | if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][0] |
1248 | && ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][0]) | |
38a448ca RH |
1249 | (target, Pmode))) |
1250 | target = copy_to_mode_reg (Pmode, target); | |
39403d82 | 1251 | size = convert_modes (mode, ptr_mode, size, 1); |
38a448ca RH |
1252 | if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][1] |
1253 | && ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][1]) | |
39403d82 DE |
1254 | (size, mode))) |
1255 | size = copy_to_mode_reg (mode, size); | |
18ca7dab | 1256 | |
38a448ca | 1257 | emit_insn (gen_allocate_stack (target, size)); |
18ca7dab RK |
1258 | } |
1259 | else | |
1260 | #endif | |
ea534b63 | 1261 | { |
38a448ca RH |
1262 | #ifndef STACK_GROWS_DOWNWARD |
1263 | emit_move_insn (target, virtual_stack_dynamic_rtx); | |
1264 | #endif | |
ea534b63 RK |
1265 | size = convert_modes (Pmode, ptr_mode, size, 1); |
1266 | anti_adjust_stack (size); | |
c9ec4f99 DM |
1267 | #ifdef SETJMP_VIA_SAVE_AREA |
1268 | if (setjmpless_size != NULL_RTX) | |
1269 | { | |
1270 | rtx note_target = get_last_insn (); | |
1271 | ||
9e6a5703 JC |
1272 | REG_NOTES (note_target) |
1273 | = gen_rtx_EXPR_LIST (REG_SAVE_AREA, setjmpless_size, | |
1274 | REG_NOTES (note_target)); | |
c9ec4f99 DM |
1275 | } |
1276 | #endif /* SETJMP_VIA_SAVE_AREA */ | |
18ca7dab RK |
1277 | #ifdef STACK_GROWS_DOWNWARD |
1278 | emit_move_insn (target, virtual_stack_dynamic_rtx); | |
1279 | #endif | |
38a448ca | 1280 | } |
18ca7dab | 1281 | |
515a7242 | 1282 | if (MUST_ALIGN) |
091ad0b9 | 1283 | { |
5244db05 | 1284 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
0f41302f MS |
1285 | but we know it can't. So add ourselves and then do |
1286 | TRUNC_DIV_EXPR. */ | |
0f56a403 | 1287 | target = expand_binop (Pmode, add_optab, target, |
5244db05 RK |
1288 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
1289 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
1290 | target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target, | |
b1ec3c92 CH |
1291 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
1292 | NULL_RTX, 1); | |
091ad0b9 | 1293 | target = expand_mult (Pmode, target, |
b1ec3c92 CH |
1294 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
1295 | NULL_RTX, 1); | |
091ad0b9 | 1296 | } |
18ca7dab RK |
1297 | |
1298 | /* Some systems require a particular insn to refer to the stack | |
1299 | to make the pages exist. */ | |
1300 | #ifdef HAVE_probe | |
1301 | if (HAVE_probe) | |
1302 | emit_insn (gen_probe ()); | |
1303 | #endif | |
1304 | ||
15fc0026 RK |
1305 | /* Record the new stack level for nonlocal gotos. */ |
1306 | if (nonlocal_goto_handler_slot != 0) | |
1307 | emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX); | |
1308 | ||
18ca7dab RK |
1309 | return target; |
1310 | } | |
1311 | \f | |
edff2491 RK |
1312 | /* Emit one stack probe at ADDRESS, an address within the stack. */ |
1313 | ||
1314 | static void | |
1315 | emit_stack_probe (address) | |
1316 | rtx address; | |
1317 | { | |
38a448ca | 1318 | rtx memref = gen_rtx_MEM (word_mode, address); |
edff2491 RK |
1319 | |
1320 | MEM_VOLATILE_P (memref) = 1; | |
1321 | ||
1322 | if (STACK_CHECK_PROBE_LOAD) | |
1323 | emit_move_insn (gen_reg_rtx (word_mode), memref); | |
1324 | else | |
1325 | emit_move_insn (memref, const0_rtx); | |
1326 | } | |
1327 | ||
1328 | /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive. | |
1329 | FIRST is a constant and size is a Pmode RTX. These are offsets from the | |
1330 | current stack pointer. STACK_GROWS_DOWNWARD says whether to add or | |
1331 | subtract from the stack. If SIZE is constant, this is done | |
1332 | with a fixed number of probes. Otherwise, we must make a loop. */ | |
1333 | ||
1334 | #ifdef STACK_GROWS_DOWNWARD | |
1335 | #define STACK_GROW_OP MINUS | |
1336 | #else | |
1337 | #define STACK_GROW_OP PLUS | |
1338 | #endif | |
1339 | ||
1340 | void | |
1341 | probe_stack_range (first, size) | |
1342 | HOST_WIDE_INT first; | |
1343 | rtx size; | |
1344 | { | |
1345 | /* First see if we have an insn to check the stack. Use it if so. */ | |
1346 | #ifdef HAVE_check_stack | |
1347 | if (HAVE_check_stack) | |
1348 | { | |
38a448ca RH |
1349 | rtx last_addr |
1350 | = force_operand (gen_rtx_STACK_GROW_OP (Pmode, | |
1351 | stack_pointer_rtx, | |
1352 | plus_constant (size, first)), | |
1353 | NULL_RTX); | |
edff2491 RK |
1354 | |
1355 | if (insn_operand_predicate[(int) CODE_FOR_check_stack][0] | |
1356 | && ! ((*insn_operand_predicate[(int) CODE_FOR_check_stack][0]) | |
1357 | (last_address, Pmode))) | |
1358 | last_address = copy_to_mode_reg (Pmode, last_address); | |
1359 | ||
1360 | emit_insn (gen_check_stack (last_address)); | |
1361 | return; | |
1362 | } | |
1363 | #endif | |
1364 | ||
1365 | /* If we have to generate explicit probes, see if we have a constant | |
95a086b1 | 1366 | small number of them to generate. If so, that's the easy case. */ |
e5e809f4 JL |
1367 | if (GET_CODE (size) == CONST_INT |
1368 | && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL) | |
edff2491 RK |
1369 | { |
1370 | HOST_WIDE_INT offset; | |
1371 | ||
1372 | /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL | |
1373 | for values of N from 1 until it exceeds LAST. If only one | |
1374 | probe is needed, this will not generate any code. Then probe | |
1375 | at LAST. */ | |
1376 | for (offset = first + STACK_CHECK_PROBE_INTERVAL; | |
1377 | offset < INTVAL (size); | |
1378 | offset = offset + STACK_CHECK_PROBE_INTERVAL) | |
38a448ca RH |
1379 | emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode, |
1380 | stack_pointer_rtx, | |
1381 | GEN_INT (offset))); | |
edff2491 | 1382 | |
38a448ca RH |
1383 | emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode, |
1384 | stack_pointer_rtx, | |
1385 | plus_constant (size, first))); | |
edff2491 RK |
1386 | } |
1387 | ||
1388 | /* In the variable case, do the same as above, but in a loop. We emit loop | |
1389 | notes so that loop optimization can be done. */ | |
1390 | else | |
1391 | { | |
1392 | rtx test_addr | |
38a448ca RH |
1393 | = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode, |
1394 | stack_pointer_rtx, | |
1395 | GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)), | |
edff2491 RK |
1396 | NULL_RTX); |
1397 | rtx last_addr | |
38a448ca RH |
1398 | = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode, |
1399 | stack_pointer_rtx, | |
1400 | plus_constant (size, first)), | |
edff2491 RK |
1401 | NULL_RTX); |
1402 | rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL); | |
1403 | rtx loop_lab = gen_label_rtx (); | |
1404 | rtx test_lab = gen_label_rtx (); | |
1405 | rtx end_lab = gen_label_rtx (); | |
1406 | rtx temp; | |
1407 | ||
1408 | if (GET_CODE (test_addr) != REG | |
1409 | || REGNO (test_addr) < FIRST_PSEUDO_REGISTER) | |
1410 | test_addr = force_reg (Pmode, test_addr); | |
1411 | ||
1412 | emit_note (NULL_PTR, NOTE_INSN_LOOP_BEG); | |
1413 | emit_jump (test_lab); | |
1414 | ||
1415 | emit_label (loop_lab); | |
1416 | emit_stack_probe (test_addr); | |
1417 | ||
1418 | emit_note (NULL_PTR, NOTE_INSN_LOOP_CONT); | |
1419 | ||
1420 | #ifdef STACK_GROWS_DOWNWARD | |
1421 | #define CMP_OPCODE GTU | |
1422 | temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr, | |
1423 | 1, OPTAB_WIDEN); | |
1424 | #else | |
1425 | #define CMP_OPCODE LTU | |
1426 | temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr, | |
1427 | 1, OPTAB_WIDEN); | |
1428 | #endif | |
1429 | ||
1430 | if (temp != test_addr) | |
1431 | abort (); | |
1432 | ||
1433 | emit_label (test_lab); | |
1434 | emit_cmp_insn (test_addr, last_addr, CMP_OPCODE, NULL_RTX, Pmode, 1, 0); | |
1435 | emit_jump_insn ((*bcc_gen_fctn[(int) CMP_OPCODE]) (loop_lab)); | |
1436 | emit_jump (end_lab); | |
1437 | emit_note (NULL_PTR, NOTE_INSN_LOOP_END); | |
1438 | emit_label (end_lab); | |
1439 | ||
38a448ca RH |
1440 | /* If will be doing stupid optimization, show test_addr is still live. */ |
1441 | if (obey_regdecls) | |
1442 | emit_insn (gen_rtx_USE (VOIDmode, test_addr)); | |
1443 | ||
edff2491 RK |
1444 | emit_stack_probe (last_addr); |
1445 | } | |
1446 | } | |
1447 | \f | |
18ca7dab RK |
1448 | /* Return an rtx representing the register or memory location |
1449 | in which a scalar value of data type VALTYPE | |
1450 | was returned by a function call to function FUNC. | |
1451 | FUNC is a FUNCTION_DECL node if the precise function is known, | |
1452 | otherwise 0. */ | |
1453 | ||
1454 | rtx | |
1455 | hard_function_value (valtype, func) | |
1456 | tree valtype; | |
1457 | tree func; | |
1458 | { | |
e1a4071f JL |
1459 | rtx val = FUNCTION_VALUE (valtype, func); |
1460 | if (GET_CODE (val) == REG | |
1461 | && GET_MODE (val) == BLKmode) | |
1462 | { | |
1463 | int bytes = int_size_in_bytes (valtype); | |
1464 | enum machine_mode tmpmode; | |
1465 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); | |
1466 | tmpmode != MAX_MACHINE_MODE; | |
1467 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) | |
1468 | { | |
1469 | /* Have we found a large enough mode? */ | |
1470 | if (GET_MODE_SIZE (tmpmode) >= bytes) | |
1471 | break; | |
1472 | } | |
1473 | ||
1474 | /* No suitable mode found. */ | |
1475 | if (tmpmode == MAX_MACHINE_MODE) | |
1476 | abort (); | |
1477 | ||
1478 | PUT_MODE (val, tmpmode); | |
1479 | } | |
1480 | return val; | |
18ca7dab RK |
1481 | } |
1482 | ||
1483 | /* Return an rtx representing the register or memory location | |
1484 | in which a scalar value of mode MODE was returned by a library call. */ | |
1485 | ||
1486 | rtx | |
1487 | hard_libcall_value (mode) | |
1488 | enum machine_mode mode; | |
1489 | { | |
1490 | return LIBCALL_VALUE (mode); | |
1491 | } | |
0c5e217d RS |
1492 | |
1493 | /* Look up the tree code for a given rtx code | |
1494 | to provide the arithmetic operation for REAL_ARITHMETIC. | |
1495 | The function returns an int because the caller may not know | |
1496 | what `enum tree_code' means. */ | |
1497 | ||
1498 | int | |
1499 | rtx_to_tree_code (code) | |
1500 | enum rtx_code code; | |
1501 | { | |
1502 | enum tree_code tcode; | |
1503 | ||
1504 | switch (code) | |
1505 | { | |
1506 | case PLUS: | |
1507 | tcode = PLUS_EXPR; | |
1508 | break; | |
1509 | case MINUS: | |
1510 | tcode = MINUS_EXPR; | |
1511 | break; | |
1512 | case MULT: | |
1513 | tcode = MULT_EXPR; | |
1514 | break; | |
1515 | case DIV: | |
1516 | tcode = RDIV_EXPR; | |
1517 | break; | |
1518 | case SMIN: | |
1519 | tcode = MIN_EXPR; | |
1520 | break; | |
1521 | case SMAX: | |
1522 | tcode = MAX_EXPR; | |
1523 | break; | |
1524 | default: | |
1525 | tcode = LAST_AND_UNUSED_TREE_CODE; | |
1526 | break; | |
1527 | } | |
1528 | return ((int) tcode); | |
1529 | } |