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18ca7dab | 1 | /* Subroutines for manipulating rtx's in semantically interesting ways. |
d7dc4377 | 2 | Copyright (C) 1987, 91, 94, 95, 96, 1997 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" | |
23 | #include "rtl.h" | |
24 | #include "tree.h" | |
25 | #include "flags.h" | |
26 | #include "expr.h" | |
27 | #include "hard-reg-set.h" | |
28 | #include "insn-config.h" | |
29 | #include "recog.h" | |
30 | #include "insn-flags.h" | |
31 | #include "insn-codes.h" | |
32 | ||
ea534b63 | 33 | static rtx break_out_memory_refs PROTO((rtx)); |
edff2491 | 34 | static void emit_stack_probe PROTO((rtx)); |
b1ec3c92 CH |
35 | /* Return an rtx for the sum of X and the integer C. |
36 | ||
8008b228 | 37 | This function should be used via the `plus_constant' macro. */ |
18ca7dab RK |
38 | |
39 | rtx | |
b1ec3c92 | 40 | plus_constant_wide (x, c) |
18ca7dab | 41 | register rtx x; |
b1ec3c92 | 42 | register HOST_WIDE_INT c; |
18ca7dab RK |
43 | { |
44 | register RTX_CODE code; | |
45 | register enum machine_mode mode; | |
46 | register rtx tem; | |
47 | int all_constant = 0; | |
48 | ||
49 | if (c == 0) | |
50 | return x; | |
51 | ||
52 | restart: | |
53 | ||
54 | code = GET_CODE (x); | |
55 | mode = GET_MODE (x); | |
56 | switch (code) | |
57 | { | |
58 | case CONST_INT: | |
b1ec3c92 | 59 | return GEN_INT (INTVAL (x) + c); |
18ca7dab RK |
60 | |
61 | case CONST_DOUBLE: | |
62 | { | |
b1ec3c92 CH |
63 | HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x); |
64 | HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x); | |
65 | HOST_WIDE_INT l2 = c; | |
66 | HOST_WIDE_INT h2 = c < 0 ? ~0 : 0; | |
67 | HOST_WIDE_INT lv, hv; | |
18ca7dab RK |
68 | |
69 | add_double (l1, h1, l2, h2, &lv, &hv); | |
70 | ||
71 | return immed_double_const (lv, hv, VOIDmode); | |
72 | } | |
73 | ||
74 | case MEM: | |
75 | /* If this is a reference to the constant pool, try replacing it with | |
76 | a reference to a new constant. If the resulting address isn't | |
77 | valid, don't return it because we have no way to validize it. */ | |
78 | if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF | |
79 | && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0))) | |
80 | { | |
81 | tem | |
82 | = force_const_mem (GET_MODE (x), | |
83 | plus_constant (get_pool_constant (XEXP (x, 0)), | |
84 | c)); | |
85 | if (memory_address_p (GET_MODE (tem), XEXP (tem, 0))) | |
86 | return tem; | |
87 | } | |
88 | break; | |
89 | ||
90 | case CONST: | |
91 | /* If adding to something entirely constant, set a flag | |
92 | so that we can add a CONST around the result. */ | |
93 | x = XEXP (x, 0); | |
94 | all_constant = 1; | |
95 | goto restart; | |
96 | ||
97 | case SYMBOL_REF: | |
98 | case LABEL_REF: | |
99 | all_constant = 1; | |
100 | break; | |
101 | ||
102 | case PLUS: | |
103 | /* The interesting case is adding the integer to a sum. | |
104 | Look for constant term in the sum and combine | |
105 | with C. For an integer constant term, we make a combined | |
106 | integer. For a constant term that is not an explicit integer, | |
e5671f2b RK |
107 | we cannot really combine, but group them together anyway. |
108 | ||
109 | Use a recursive call in case the remaining operand is something | |
110 | that we handle specially, such as a SYMBOL_REF. */ | |
111 | ||
112 | if (GET_CODE (XEXP (x, 1)) == CONST_INT) | |
113 | return plus_constant (XEXP (x, 0), c + INTVAL (XEXP (x, 1))); | |
18ca7dab RK |
114 | else if (CONSTANT_P (XEXP (x, 0))) |
115 | return gen_rtx (PLUS, mode, | |
116 | plus_constant (XEXP (x, 0), c), | |
117 | XEXP (x, 1)); | |
118 | else if (CONSTANT_P (XEXP (x, 1))) | |
119 | return gen_rtx (PLUS, mode, | |
120 | XEXP (x, 0), | |
121 | plus_constant (XEXP (x, 1), c)); | |
122 | } | |
123 | ||
124 | if (c != 0) | |
b1ec3c92 | 125 | x = gen_rtx (PLUS, mode, x, GEN_INT (c)); |
18ca7dab RK |
126 | |
127 | if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF) | |
128 | return x; | |
129 | else if (all_constant) | |
130 | return gen_rtx (CONST, mode, x); | |
131 | else | |
132 | return x; | |
133 | } | |
134 | ||
b1ec3c92 CH |
135 | /* This is the same as `plus_constant', except that it handles LO_SUM. |
136 | ||
137 | This function should be used via the `plus_constant_for_output' macro. */ | |
18ca7dab RK |
138 | |
139 | rtx | |
b1ec3c92 | 140 | plus_constant_for_output_wide (x, c) |
18ca7dab | 141 | register rtx x; |
b1ec3c92 | 142 | register HOST_WIDE_INT c; |
18ca7dab RK |
143 | { |
144 | register RTX_CODE code = GET_CODE (x); | |
145 | register enum machine_mode mode = GET_MODE (x); | |
146 | int all_constant = 0; | |
147 | ||
148 | if (GET_CODE (x) == LO_SUM) | |
149 | return gen_rtx (LO_SUM, mode, XEXP (x, 0), | |
150 | plus_constant_for_output (XEXP (x, 1), c)); | |
151 | ||
152 | else | |
153 | return plus_constant (x, c); | |
154 | } | |
155 | \f | |
156 | /* If X is a sum, return a new sum like X but lacking any constant terms. | |
157 | Add all the removed constant terms into *CONSTPTR. | |
158 | X itself is not altered. The result != X if and only if | |
159 | it is not isomorphic to X. */ | |
160 | ||
161 | rtx | |
162 | eliminate_constant_term (x, constptr) | |
163 | rtx x; | |
164 | rtx *constptr; | |
165 | { | |
166 | register rtx x0, x1; | |
167 | rtx tem; | |
168 | ||
169 | if (GET_CODE (x) != PLUS) | |
170 | return x; | |
171 | ||
172 | /* First handle constants appearing at this level explicitly. */ | |
173 | if (GET_CODE (XEXP (x, 1)) == CONST_INT | |
174 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr, | |
175 | XEXP (x, 1))) | |
176 | && GET_CODE (tem) == CONST_INT) | |
177 | { | |
178 | *constptr = tem; | |
179 | return eliminate_constant_term (XEXP (x, 0), constptr); | |
180 | } | |
181 | ||
182 | tem = const0_rtx; | |
183 | x0 = eliminate_constant_term (XEXP (x, 0), &tem); | |
184 | x1 = eliminate_constant_term (XEXP (x, 1), &tem); | |
185 | if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0)) | |
186 | && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), | |
187 | *constptr, tem)) | |
188 | && GET_CODE (tem) == CONST_INT) | |
189 | { | |
190 | *constptr = tem; | |
191 | return gen_rtx (PLUS, GET_MODE (x), x0, x1); | |
192 | } | |
193 | ||
194 | return x; | |
195 | } | |
196 | ||
197 | /* Returns the insn that next references REG after INSN, or 0 | |
198 | if REG is clobbered before next referenced or we cannot find | |
199 | an insn that references REG in a straight-line piece of code. */ | |
200 | ||
201 | rtx | |
202 | find_next_ref (reg, insn) | |
203 | rtx reg; | |
204 | rtx insn; | |
205 | { | |
206 | rtx next; | |
207 | ||
208 | for (insn = NEXT_INSN (insn); insn; insn = next) | |
209 | { | |
210 | next = NEXT_INSN (insn); | |
211 | if (GET_CODE (insn) == NOTE) | |
212 | continue; | |
213 | if (GET_CODE (insn) == CODE_LABEL | |
214 | || GET_CODE (insn) == BARRIER) | |
215 | return 0; | |
216 | if (GET_CODE (insn) == INSN | |
217 | || GET_CODE (insn) == JUMP_INSN | |
218 | || GET_CODE (insn) == CALL_INSN) | |
219 | { | |
220 | if (reg_set_p (reg, insn)) | |
221 | return 0; | |
222 | if (reg_mentioned_p (reg, PATTERN (insn))) | |
223 | return insn; | |
224 | if (GET_CODE (insn) == JUMP_INSN) | |
225 | { | |
226 | if (simplejump_p (insn)) | |
227 | next = JUMP_LABEL (insn); | |
228 | else | |
229 | return 0; | |
230 | } | |
231 | if (GET_CODE (insn) == CALL_INSN | |
232 | && REGNO (reg) < FIRST_PSEUDO_REGISTER | |
233 | && call_used_regs[REGNO (reg)]) | |
234 | return 0; | |
235 | } | |
236 | else | |
237 | abort (); | |
238 | } | |
239 | return 0; | |
240 | } | |
241 | ||
242 | /* Return an rtx for the size in bytes of the value of EXP. */ | |
243 | ||
244 | rtx | |
245 | expr_size (exp) | |
246 | tree exp; | |
247 | { | |
99098c66 RK |
248 | tree size = size_in_bytes (TREE_TYPE (exp)); |
249 | ||
250 | if (TREE_CODE (size) != INTEGER_CST | |
251 | && contains_placeholder_p (size)) | |
252 | size = build (WITH_RECORD_EXPR, sizetype, size, exp); | |
253 | ||
254 | return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), 0); | |
18ca7dab RK |
255 | } |
256 | \f | |
257 | /* Return a copy of X in which all memory references | |
258 | and all constants that involve symbol refs | |
259 | have been replaced with new temporary registers. | |
260 | Also emit code to load the memory locations and constants | |
261 | into those registers. | |
262 | ||
263 | If X contains no such constants or memory references, | |
264 | X itself (not a copy) is returned. | |
265 | ||
266 | If a constant is found in the address that is not a legitimate constant | |
267 | in an insn, it is left alone in the hope that it might be valid in the | |
268 | address. | |
269 | ||
270 | X may contain no arithmetic except addition, subtraction and multiplication. | |
271 | Values returned by expand_expr with 1 for sum_ok fit this constraint. */ | |
272 | ||
273 | static rtx | |
274 | break_out_memory_refs (x) | |
275 | register rtx x; | |
276 | { | |
277 | if (GET_CODE (x) == MEM | |
cabeca29 | 278 | || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x) |
18ca7dab | 279 | && GET_MODE (x) != VOIDmode)) |
2cca6e3f | 280 | x = force_reg (GET_MODE (x), x); |
18ca7dab RK |
281 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS |
282 | || GET_CODE (x) == MULT) | |
283 | { | |
284 | register rtx op0 = break_out_memory_refs (XEXP (x, 0)); | |
285 | register rtx op1 = break_out_memory_refs (XEXP (x, 1)); | |
2cca6e3f | 286 | |
18ca7dab RK |
287 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) |
288 | x = gen_rtx (GET_CODE (x), Pmode, op0, op1); | |
289 | } | |
2cca6e3f | 290 | |
18ca7dab RK |
291 | return x; |
292 | } | |
293 | ||
ea534b63 RK |
294 | #ifdef POINTERS_EXTEND_UNSIGNED |
295 | ||
296 | /* Given X, a memory address in ptr_mode, convert it to an address | |
498b529f RK |
297 | in Pmode, or vice versa (TO_MODE says which way). We take advantage of |
298 | the fact that pointers are not allowed to overflow by commuting arithmetic | |
299 | operations over conversions so that address arithmetic insns can be | |
300 | used. */ | |
ea534b63 | 301 | |
498b529f RK |
302 | rtx |
303 | convert_memory_address (to_mode, x) | |
304 | enum machine_mode to_mode; | |
ea534b63 RK |
305 | rtx x; |
306 | { | |
0b04ec8c | 307 | enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode; |
498b529f RK |
308 | rtx temp; |
309 | ||
0b04ec8c RK |
310 | /* Here we handle some special cases. If none of them apply, fall through |
311 | to the default case. */ | |
ea534b63 RK |
312 | switch (GET_CODE (x)) |
313 | { | |
314 | case CONST_INT: | |
315 | case CONST_DOUBLE: | |
498b529f RK |
316 | return x; |
317 | ||
ea534b63 | 318 | case LABEL_REF: |
498b529f RK |
319 | return gen_rtx (LABEL_REF, to_mode, XEXP (x, 0)); |
320 | ||
ea534b63 | 321 | case SYMBOL_REF: |
498b529f RK |
322 | temp = gen_rtx (SYMBOL_REF, to_mode, XSTR (x, 0)); |
323 | SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x); | |
d7dc4377 | 324 | CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x); |
498b529f | 325 | return temp; |
ea534b63 | 326 | |
498b529f RK |
327 | case CONST: |
328 | return gen_rtx (CONST, to_mode, | |
329 | convert_memory_address (to_mode, XEXP (x, 0))); | |
ea534b63 | 330 | |
0b04ec8c RK |
331 | case PLUS: |
332 | case MULT: | |
333 | /* For addition the second operand is a small constant, we can safely | |
334 | permute the converstion and addition operation. We can always safely | |
60725c78 RK |
335 | permute them if we are making the address narrower. In addition, |
336 | always permute the operations if this is a constant. */ | |
0b04ec8c RK |
337 | if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode) |
338 | || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT | |
60725c78 RK |
339 | && (INTVAL (XEXP (x, 1)) + 20000 < 40000 |
340 | || CONSTANT_P (XEXP (x, 0))))) | |
0b04ec8c RK |
341 | return gen_rtx (GET_CODE (x), to_mode, |
342 | convert_memory_address (to_mode, XEXP (x, 0)), | |
343 | convert_memory_address (to_mode, XEXP (x, 1))); | |
ea534b63 | 344 | } |
0b04ec8c RK |
345 | |
346 | return convert_modes (to_mode, from_mode, | |
347 | x, POINTERS_EXTEND_UNSIGNED); | |
ea534b63 RK |
348 | } |
349 | #endif | |
350 | ||
18ca7dab RK |
351 | /* Given a memory address or facsimile X, construct a new address, |
352 | currently equivalent, that is stable: future stores won't change it. | |
353 | ||
354 | X must be composed of constants, register and memory references | |
355 | combined with addition, subtraction and multiplication: | |
356 | in other words, just what you can get from expand_expr if sum_ok is 1. | |
357 | ||
358 | Works by making copies of all regs and memory locations used | |
359 | by X and combining them the same way X does. | |
360 | You could also stabilize the reference to this address | |
361 | by copying the address to a register with copy_to_reg; | |
362 | but then you wouldn't get indexed addressing in the reference. */ | |
363 | ||
364 | rtx | |
365 | copy_all_regs (x) | |
366 | register rtx x; | |
367 | { | |
368 | if (GET_CODE (x) == REG) | |
369 | { | |
11c50c5e DE |
370 | if (REGNO (x) != FRAME_POINTER_REGNUM |
371 | #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM | |
372 | && REGNO (x) != HARD_FRAME_POINTER_REGNUM | |
373 | #endif | |
374 | ) | |
18ca7dab RK |
375 | x = copy_to_reg (x); |
376 | } | |
377 | else if (GET_CODE (x) == MEM) | |
378 | x = copy_to_reg (x); | |
379 | else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS | |
380 | || GET_CODE (x) == MULT) | |
381 | { | |
382 | register rtx op0 = copy_all_regs (XEXP (x, 0)); | |
383 | register rtx op1 = copy_all_regs (XEXP (x, 1)); | |
384 | if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1)) | |
385 | x = gen_rtx (GET_CODE (x), Pmode, op0, op1); | |
386 | } | |
387 | return x; | |
388 | } | |
389 | \f | |
390 | /* Return something equivalent to X but valid as a memory address | |
391 | for something of mode MODE. When X is not itself valid, this | |
392 | works by copying X or subexpressions of it into registers. */ | |
393 | ||
394 | rtx | |
395 | memory_address (mode, x) | |
396 | enum machine_mode mode; | |
397 | register rtx x; | |
398 | { | |
18b9ca6f | 399 | register rtx oldx = x; |
18ca7dab | 400 | |
ea534b63 RK |
401 | #ifdef POINTERS_EXTEND_UNSIGNED |
402 | if (GET_MODE (x) == ptr_mode) | |
498b529f | 403 | x = convert_memory_address (Pmode, x); |
ea534b63 RK |
404 | #endif |
405 | ||
18ca7dab RK |
406 | /* By passing constant addresses thru registers |
407 | we get a chance to cse them. */ | |
cabeca29 | 408 | if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)) |
18b9ca6f | 409 | x = force_reg (Pmode, x); |
18ca7dab RK |
410 | |
411 | /* Accept a QUEUED that refers to a REG | |
412 | even though that isn't a valid address. | |
413 | On attempting to put this in an insn we will call protect_from_queue | |
414 | which will turn it into a REG, which is valid. */ | |
18b9ca6f | 415 | else if (GET_CODE (x) == QUEUED |
18ca7dab | 416 | && GET_CODE (QUEUED_VAR (x)) == REG) |
18b9ca6f | 417 | ; |
18ca7dab RK |
418 | |
419 | /* We get better cse by rejecting indirect addressing at this stage. | |
420 | Let the combiner create indirect addresses where appropriate. | |
421 | For now, generate the code so that the subexpressions useful to share | |
422 | are visible. But not if cse won't be done! */ | |
18b9ca6f | 423 | else |
18ca7dab | 424 | { |
18b9ca6f RK |
425 | if (! cse_not_expected && GET_CODE (x) != REG) |
426 | x = break_out_memory_refs (x); | |
427 | ||
428 | /* At this point, any valid address is accepted. */ | |
429 | GO_IF_LEGITIMATE_ADDRESS (mode, x, win); | |
430 | ||
431 | /* If it was valid before but breaking out memory refs invalidated it, | |
432 | use it the old way. */ | |
433 | if (memory_address_p (mode, oldx)) | |
434 | goto win2; | |
435 | ||
436 | /* Perform machine-dependent transformations on X | |
437 | in certain cases. This is not necessary since the code | |
438 | below can handle all possible cases, but machine-dependent | |
439 | transformations can make better code. */ | |
440 | LEGITIMIZE_ADDRESS (x, oldx, mode, win); | |
441 | ||
442 | /* PLUS and MULT can appear in special ways | |
443 | as the result of attempts to make an address usable for indexing. | |
444 | Usually they are dealt with by calling force_operand, below. | |
445 | But a sum containing constant terms is special | |
446 | if removing them makes the sum a valid address: | |
447 | then we generate that address in a register | |
448 | and index off of it. We do this because it often makes | |
449 | shorter code, and because the addresses thus generated | |
450 | in registers often become common subexpressions. */ | |
451 | if (GET_CODE (x) == PLUS) | |
452 | { | |
453 | rtx constant_term = const0_rtx; | |
454 | rtx y = eliminate_constant_term (x, &constant_term); | |
455 | if (constant_term == const0_rtx | |
456 | || ! memory_address_p (mode, y)) | |
457 | x = force_operand (x, NULL_RTX); | |
458 | else | |
459 | { | |
460 | y = gen_rtx (PLUS, GET_MODE (x), copy_to_reg (y), constant_term); | |
461 | if (! memory_address_p (mode, y)) | |
462 | x = force_operand (x, NULL_RTX); | |
463 | else | |
464 | x = y; | |
465 | } | |
466 | } | |
18ca7dab | 467 | |
e475ed2a | 468 | else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS) |
18b9ca6f | 469 | x = force_operand (x, NULL_RTX); |
18ca7dab | 470 | |
18b9ca6f RK |
471 | /* If we have a register that's an invalid address, |
472 | it must be a hard reg of the wrong class. Copy it to a pseudo. */ | |
473 | else if (GET_CODE (x) == REG) | |
474 | x = copy_to_reg (x); | |
475 | ||
476 | /* Last resort: copy the value to a register, since | |
477 | the register is a valid address. */ | |
478 | else | |
479 | x = force_reg (Pmode, x); | |
480 | ||
481 | goto done; | |
18ca7dab | 482 | |
c02a7fbb RK |
483 | win2: |
484 | x = oldx; | |
485 | win: | |
486 | if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG | |
487 | /* Don't copy an addr via a reg if it is one of our stack slots. */ | |
488 | && ! (GET_CODE (x) == PLUS | |
489 | && (XEXP (x, 0) == virtual_stack_vars_rtx | |
490 | || XEXP (x, 0) == virtual_incoming_args_rtx))) | |
491 | { | |
492 | if (general_operand (x, Pmode)) | |
493 | x = force_reg (Pmode, x); | |
494 | else | |
495 | x = force_operand (x, NULL_RTX); | |
496 | } | |
18ca7dab | 497 | } |
18b9ca6f RK |
498 | |
499 | done: | |
500 | ||
2cca6e3f RK |
501 | /* If we didn't change the address, we are done. Otherwise, mark |
502 | a reg as a pointer if we have REG or REG + CONST_INT. */ | |
503 | if (oldx == x) | |
504 | return x; | |
505 | else if (GET_CODE (x) == REG) | |
305f22b5 | 506 | mark_reg_pointer (x, 1); |
2cca6e3f RK |
507 | else if (GET_CODE (x) == PLUS |
508 | && GET_CODE (XEXP (x, 0)) == REG | |
509 | && GET_CODE (XEXP (x, 1)) == CONST_INT) | |
305f22b5 | 510 | mark_reg_pointer (XEXP (x, 0), 1); |
2cca6e3f | 511 | |
18b9ca6f RK |
512 | /* OLDX may have been the address on a temporary. Update the address |
513 | to indicate that X is now used. */ | |
514 | update_temp_slot_address (oldx, x); | |
515 | ||
18ca7dab RK |
516 | return x; |
517 | } | |
518 | ||
519 | /* Like `memory_address' but pretend `flag_force_addr' is 0. */ | |
520 | ||
521 | rtx | |
522 | memory_address_noforce (mode, x) | |
523 | enum machine_mode mode; | |
524 | rtx x; | |
525 | { | |
526 | int ambient_force_addr = flag_force_addr; | |
527 | rtx val; | |
528 | ||
529 | flag_force_addr = 0; | |
530 | val = memory_address (mode, x); | |
531 | flag_force_addr = ambient_force_addr; | |
532 | return val; | |
533 | } | |
534 | ||
535 | /* Convert a mem ref into one with a valid memory address. | |
536 | Pass through anything else unchanged. */ | |
537 | ||
538 | rtx | |
539 | validize_mem (ref) | |
540 | rtx ref; | |
541 | { | |
542 | if (GET_CODE (ref) != MEM) | |
543 | return ref; | |
544 | if (memory_address_p (GET_MODE (ref), XEXP (ref, 0))) | |
545 | return ref; | |
546 | /* Don't alter REF itself, since that is probably a stack slot. */ | |
547 | return change_address (ref, GET_MODE (ref), XEXP (ref, 0)); | |
548 | } | |
549 | \f | |
550 | /* Return a modified copy of X with its memory address copied | |
551 | into a temporary register to protect it from side effects. | |
552 | If X is not a MEM, it is returned unchanged (and not copied). | |
553 | Perhaps even if it is a MEM, if there is no need to change it. */ | |
554 | ||
555 | rtx | |
556 | stabilize (x) | |
557 | rtx x; | |
558 | { | |
559 | register rtx addr; | |
560 | if (GET_CODE (x) != MEM) | |
561 | return x; | |
562 | addr = XEXP (x, 0); | |
563 | if (rtx_unstable_p (addr)) | |
564 | { | |
565 | rtx temp = copy_all_regs (addr); | |
566 | rtx mem; | |
567 | if (GET_CODE (temp) != REG) | |
568 | temp = copy_to_reg (temp); | |
569 | mem = gen_rtx (MEM, GET_MODE (x), temp); | |
570 | ||
571 | /* Mark returned memref with in_struct if it's in an array or | |
572 | structure. Copy const and volatile from original memref. */ | |
573 | ||
574 | MEM_IN_STRUCT_P (mem) = MEM_IN_STRUCT_P (x) || GET_CODE (addr) == PLUS; | |
575 | RTX_UNCHANGING_P (mem) = RTX_UNCHANGING_P (x); | |
576 | MEM_VOLATILE_P (mem) = MEM_VOLATILE_P (x); | |
577 | return mem; | |
578 | } | |
579 | return x; | |
580 | } | |
581 | \f | |
582 | /* Copy the value or contents of X to a new temp reg and return that reg. */ | |
583 | ||
584 | rtx | |
585 | copy_to_reg (x) | |
586 | rtx x; | |
587 | { | |
588 | register rtx temp = gen_reg_rtx (GET_MODE (x)); | |
589 | ||
590 | /* If not an operand, must be an address with PLUS and MULT so | |
591 | do the computation. */ | |
592 | if (! general_operand (x, VOIDmode)) | |
593 | x = force_operand (x, temp); | |
594 | ||
595 | if (x != temp) | |
596 | emit_move_insn (temp, x); | |
597 | ||
598 | return temp; | |
599 | } | |
600 | ||
601 | /* Like copy_to_reg but always give the new register mode Pmode | |
602 | in case X is a constant. */ | |
603 | ||
604 | rtx | |
605 | copy_addr_to_reg (x) | |
606 | rtx x; | |
607 | { | |
608 | return copy_to_mode_reg (Pmode, x); | |
609 | } | |
610 | ||
611 | /* Like copy_to_reg but always give the new register mode MODE | |
612 | in case X is a constant. */ | |
613 | ||
614 | rtx | |
615 | copy_to_mode_reg (mode, x) | |
616 | enum machine_mode mode; | |
617 | rtx x; | |
618 | { | |
619 | register rtx temp = gen_reg_rtx (mode); | |
620 | ||
621 | /* If not an operand, must be an address with PLUS and MULT so | |
622 | do the computation. */ | |
623 | if (! general_operand (x, VOIDmode)) | |
624 | x = force_operand (x, temp); | |
625 | ||
626 | if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode) | |
627 | abort (); | |
628 | if (x != temp) | |
629 | emit_move_insn (temp, x); | |
630 | return temp; | |
631 | } | |
632 | ||
633 | /* Load X into a register if it is not already one. | |
634 | Use mode MODE for the register. | |
635 | X should be valid for mode MODE, but it may be a constant which | |
636 | is valid for all integer modes; that's why caller must specify MODE. | |
637 | ||
638 | The caller must not alter the value in the register we return, | |
639 | since we mark it as a "constant" register. */ | |
640 | ||
641 | rtx | |
642 | force_reg (mode, x) | |
643 | enum machine_mode mode; | |
644 | rtx x; | |
645 | { | |
62874575 | 646 | register rtx temp, insn, set; |
18ca7dab RK |
647 | |
648 | if (GET_CODE (x) == REG) | |
649 | return x; | |
650 | temp = gen_reg_rtx (mode); | |
651 | insn = emit_move_insn (temp, x); | |
62874575 | 652 | |
18ca7dab | 653 | /* Let optimizers know that TEMP's value never changes |
62874575 RK |
654 | and that X can be substituted for it. Don't get confused |
655 | if INSN set something else (such as a SUBREG of TEMP). */ | |
656 | if (CONSTANT_P (x) | |
657 | && (set = single_set (insn)) != 0 | |
658 | && SET_DEST (set) == temp) | |
18ca7dab | 659 | { |
b1ec3c92 | 660 | rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX); |
18ca7dab RK |
661 | |
662 | if (note) | |
663 | XEXP (note, 0) = x; | |
664 | else | |
665 | REG_NOTES (insn) = gen_rtx (EXPR_LIST, REG_EQUAL, x, REG_NOTES (insn)); | |
666 | } | |
667 | return temp; | |
668 | } | |
669 | ||
670 | /* If X is a memory ref, copy its contents to a new temp reg and return | |
671 | that reg. Otherwise, return X. */ | |
672 | ||
673 | rtx | |
674 | force_not_mem (x) | |
675 | rtx x; | |
676 | { | |
677 | register rtx temp; | |
678 | if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode) | |
679 | return x; | |
680 | temp = gen_reg_rtx (GET_MODE (x)); | |
681 | emit_move_insn (temp, x); | |
682 | return temp; | |
683 | } | |
684 | ||
685 | /* Copy X to TARGET (if it's nonzero and a reg) | |
686 | or to a new temp reg and return that reg. | |
687 | MODE is the mode to use for X in case it is a constant. */ | |
688 | ||
689 | rtx | |
690 | copy_to_suggested_reg (x, target, mode) | |
691 | rtx x, target; | |
692 | enum machine_mode mode; | |
693 | { | |
694 | register rtx temp; | |
695 | ||
696 | if (target && GET_CODE (target) == REG) | |
697 | temp = target; | |
698 | else | |
699 | temp = gen_reg_rtx (mode); | |
700 | ||
701 | emit_move_insn (temp, x); | |
702 | return temp; | |
703 | } | |
704 | \f | |
9ff65789 RK |
705 | /* Return the mode to use to store a scalar of TYPE and MODE. |
706 | PUNSIGNEDP points to the signedness of the type and may be adjusted | |
707 | to show what signedness to use on extension operations. | |
708 | ||
709 | FOR_CALL is non-zero if this call is promoting args for a call. */ | |
710 | ||
711 | enum machine_mode | |
712 | promote_mode (type, mode, punsignedp, for_call) | |
713 | tree type; | |
714 | enum machine_mode mode; | |
715 | int *punsignedp; | |
716 | int for_call; | |
717 | { | |
718 | enum tree_code code = TREE_CODE (type); | |
719 | int unsignedp = *punsignedp; | |
720 | ||
721 | #ifdef PROMOTE_FOR_CALL_ONLY | |
722 | if (! for_call) | |
723 | return mode; | |
724 | #endif | |
725 | ||
726 | switch (code) | |
727 | { | |
728 | #ifdef PROMOTE_MODE | |
729 | case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE: | |
730 | case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE: | |
731 | PROMOTE_MODE (mode, unsignedp, type); | |
732 | break; | |
733 | #endif | |
734 | ||
ea534b63 | 735 | #ifdef POINTERS_EXTEND_UNSIGNED |
56a4c9e2 | 736 | case REFERENCE_TYPE: |
9ff65789 | 737 | case POINTER_TYPE: |
ea534b63 RK |
738 | mode = Pmode; |
739 | unsignedp = POINTERS_EXTEND_UNSIGNED; | |
9ff65789 | 740 | break; |
ea534b63 | 741 | #endif |
9ff65789 RK |
742 | } |
743 | ||
744 | *punsignedp = unsignedp; | |
745 | return mode; | |
746 | } | |
747 | \f | |
18ca7dab RK |
748 | /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes). |
749 | This pops when ADJUST is positive. ADJUST need not be constant. */ | |
750 | ||
751 | void | |
752 | adjust_stack (adjust) | |
753 | rtx adjust; | |
754 | { | |
755 | rtx temp; | |
756 | adjust = protect_from_queue (adjust, 0); | |
757 | ||
758 | if (adjust == const0_rtx) | |
759 | return; | |
760 | ||
761 | temp = expand_binop (Pmode, | |
762 | #ifdef STACK_GROWS_DOWNWARD | |
763 | add_optab, | |
764 | #else | |
765 | sub_optab, | |
766 | #endif | |
767 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, | |
768 | OPTAB_LIB_WIDEN); | |
769 | ||
770 | if (temp != stack_pointer_rtx) | |
771 | emit_move_insn (stack_pointer_rtx, temp); | |
772 | } | |
773 | ||
774 | /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes). | |
775 | This pushes when ADJUST is positive. ADJUST need not be constant. */ | |
776 | ||
777 | void | |
778 | anti_adjust_stack (adjust) | |
779 | rtx adjust; | |
780 | { | |
781 | rtx temp; | |
782 | adjust = protect_from_queue (adjust, 0); | |
783 | ||
784 | if (adjust == const0_rtx) | |
785 | return; | |
786 | ||
787 | temp = expand_binop (Pmode, | |
788 | #ifdef STACK_GROWS_DOWNWARD | |
789 | sub_optab, | |
790 | #else | |
791 | add_optab, | |
792 | #endif | |
793 | stack_pointer_rtx, adjust, stack_pointer_rtx, 0, | |
794 | OPTAB_LIB_WIDEN); | |
795 | ||
796 | if (temp != stack_pointer_rtx) | |
797 | emit_move_insn (stack_pointer_rtx, temp); | |
798 | } | |
799 | ||
800 | /* Round the size of a block to be pushed up to the boundary required | |
801 | by this machine. SIZE is the desired size, which need not be constant. */ | |
802 | ||
803 | rtx | |
804 | round_push (size) | |
805 | rtx size; | |
806 | { | |
807 | #ifdef STACK_BOUNDARY | |
808 | int align = STACK_BOUNDARY / BITS_PER_UNIT; | |
809 | if (align == 1) | |
810 | return size; | |
811 | if (GET_CODE (size) == CONST_INT) | |
812 | { | |
813 | int new = (INTVAL (size) + align - 1) / align * align; | |
814 | if (INTVAL (size) != new) | |
b1ec3c92 | 815 | size = GEN_INT (new); |
18ca7dab RK |
816 | } |
817 | else | |
818 | { | |
5244db05 | 819 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
0f41302f MS |
820 | but we know it can't. So add ourselves and then do |
821 | TRUNC_DIV_EXPR. */ | |
5244db05 RK |
822 | size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1), |
823 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
824 | size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align), | |
b1ec3c92 CH |
825 | NULL_RTX, 1); |
826 | size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1); | |
18ca7dab RK |
827 | } |
828 | #endif /* STACK_BOUNDARY */ | |
829 | return size; | |
830 | } | |
831 | \f | |
59257ff7 RK |
832 | /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer |
833 | to a previously-created save area. If no save area has been allocated, | |
834 | this function will allocate one. If a save area is specified, it | |
835 | must be of the proper mode. | |
836 | ||
837 | The insns are emitted after insn AFTER, if nonzero, otherwise the insns | |
838 | are emitted at the current position. */ | |
839 | ||
840 | void | |
841 | emit_stack_save (save_level, psave, after) | |
842 | enum save_level save_level; | |
843 | rtx *psave; | |
844 | rtx after; | |
845 | { | |
846 | rtx sa = *psave; | |
847 | /* The default is that we use a move insn and save in a Pmode object. */ | |
848 | rtx (*fcn) () = gen_move_insn; | |
849 | enum machine_mode mode = Pmode; | |
850 | ||
851 | /* See if this machine has anything special to do for this kind of save. */ | |
852 | switch (save_level) | |
853 | { | |
854 | #ifdef HAVE_save_stack_block | |
855 | case SAVE_BLOCK: | |
856 | if (HAVE_save_stack_block) | |
857 | { | |
858 | fcn = gen_save_stack_block; | |
859 | mode = insn_operand_mode[CODE_FOR_save_stack_block][0]; | |
860 | } | |
861 | break; | |
862 | #endif | |
863 | #ifdef HAVE_save_stack_function | |
864 | case SAVE_FUNCTION: | |
865 | if (HAVE_save_stack_function) | |
866 | { | |
867 | fcn = gen_save_stack_function; | |
868 | mode = insn_operand_mode[CODE_FOR_save_stack_function][0]; | |
869 | } | |
870 | break; | |
871 | #endif | |
872 | #ifdef HAVE_save_stack_nonlocal | |
873 | case SAVE_NONLOCAL: | |
874 | if (HAVE_save_stack_nonlocal) | |
875 | { | |
876 | fcn = gen_save_stack_nonlocal; | |
0d69ab6f | 877 | mode = insn_operand_mode[(int) CODE_FOR_save_stack_nonlocal][0]; |
59257ff7 RK |
878 | } |
879 | break; | |
880 | #endif | |
881 | } | |
882 | ||
883 | /* If there is no save area and we have to allocate one, do so. Otherwise | |
884 | verify the save area is the proper mode. */ | |
885 | ||
886 | if (sa == 0) | |
887 | { | |
888 | if (mode != VOIDmode) | |
889 | { | |
890 | if (save_level == SAVE_NONLOCAL) | |
891 | *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0); | |
892 | else | |
893 | *psave = sa = gen_reg_rtx (mode); | |
894 | } | |
895 | } | |
896 | else | |
897 | { | |
898 | if (mode == VOIDmode || GET_MODE (sa) != mode) | |
899 | abort (); | |
900 | } | |
901 | ||
902 | if (after) | |
700f6f98 RK |
903 | { |
904 | rtx seq; | |
905 | ||
906 | start_sequence (); | |
5460015d JW |
907 | /* We must validize inside the sequence, to ensure that any instructions |
908 | created by the validize call also get moved to the right place. */ | |
909 | if (sa != 0) | |
910 | sa = validize_mem (sa); | |
d072107f | 911 | emit_insn (fcn (sa, stack_pointer_rtx)); |
700f6f98 RK |
912 | seq = gen_sequence (); |
913 | end_sequence (); | |
914 | emit_insn_after (seq, after); | |
915 | } | |
59257ff7 | 916 | else |
5460015d JW |
917 | { |
918 | if (sa != 0) | |
919 | sa = validize_mem (sa); | |
920 | emit_insn (fcn (sa, stack_pointer_rtx)); | |
921 | } | |
59257ff7 RK |
922 | } |
923 | ||
924 | /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save | |
925 | area made by emit_stack_save. If it is zero, we have nothing to do. | |
926 | ||
927 | Put any emitted insns after insn AFTER, if nonzero, otherwise at | |
928 | current position. */ | |
929 | ||
930 | void | |
931 | emit_stack_restore (save_level, sa, after) | |
932 | enum save_level save_level; | |
933 | rtx after; | |
934 | rtx sa; | |
935 | { | |
936 | /* The default is that we use a move insn. */ | |
937 | rtx (*fcn) () = gen_move_insn; | |
938 | ||
939 | /* See if this machine has anything special to do for this kind of save. */ | |
940 | switch (save_level) | |
941 | { | |
942 | #ifdef HAVE_restore_stack_block | |
943 | case SAVE_BLOCK: | |
944 | if (HAVE_restore_stack_block) | |
945 | fcn = gen_restore_stack_block; | |
946 | break; | |
947 | #endif | |
948 | #ifdef HAVE_restore_stack_function | |
949 | case SAVE_FUNCTION: | |
950 | if (HAVE_restore_stack_function) | |
951 | fcn = gen_restore_stack_function; | |
952 | break; | |
953 | #endif | |
954 | #ifdef HAVE_restore_stack_nonlocal | |
955 | ||
956 | case SAVE_NONLOCAL: | |
957 | if (HAVE_restore_stack_nonlocal) | |
958 | fcn = gen_restore_stack_nonlocal; | |
959 | break; | |
960 | #endif | |
961 | } | |
962 | ||
d072107f RK |
963 | if (sa != 0) |
964 | sa = validize_mem (sa); | |
965 | ||
59257ff7 | 966 | if (after) |
700f6f98 RK |
967 | { |
968 | rtx seq; | |
969 | ||
970 | start_sequence (); | |
d072107f | 971 | emit_insn (fcn (stack_pointer_rtx, sa)); |
700f6f98 RK |
972 | seq = gen_sequence (); |
973 | end_sequence (); | |
974 | emit_insn_after (seq, after); | |
975 | } | |
59257ff7 | 976 | else |
d072107f | 977 | emit_insn (fcn (stack_pointer_rtx, sa)); |
59257ff7 RK |
978 | } |
979 | \f | |
18ca7dab RK |
980 | /* Return an rtx representing the address of an area of memory dynamically |
981 | pushed on the stack. This region of memory is always aligned to | |
982 | a multiple of BIGGEST_ALIGNMENT. | |
983 | ||
984 | Any required stack pointer alignment is preserved. | |
985 | ||
986 | SIZE is an rtx representing the size of the area. | |
091ad0b9 RK |
987 | TARGET is a place in which the address can be placed. |
988 | ||
989 | KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */ | |
18ca7dab RK |
990 | |
991 | rtx | |
091ad0b9 | 992 | allocate_dynamic_stack_space (size, target, known_align) |
18ca7dab RK |
993 | rtx size; |
994 | rtx target; | |
091ad0b9 | 995 | int known_align; |
18ca7dab | 996 | { |
15fc0026 | 997 | /* If we're asking for zero bytes, it doesn't matter what we point |
9faa82d8 | 998 | to since we can't dereference it. But return a reasonable |
15fc0026 RK |
999 | address anyway. */ |
1000 | if (size == const0_rtx) | |
1001 | return virtual_stack_dynamic_rtx; | |
1002 | ||
1003 | /* Otherwise, show we're calling alloca or equivalent. */ | |
1004 | current_function_calls_alloca = 1; | |
1005 | ||
18ca7dab RK |
1006 | /* Ensure the size is in the proper mode. */ |
1007 | if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode) | |
1008 | size = convert_to_mode (Pmode, size, 1); | |
1009 | ||
1010 | /* We will need to ensure that the address we return is aligned to | |
1011 | BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't | |
1012 | always know its final value at this point in the compilation (it | |
1013 | might depend on the size of the outgoing parameter lists, for | |
1014 | example), so we must align the value to be returned in that case. | |
1015 | (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if | |
1016 | STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined). | |
1017 | We must also do an alignment operation on the returned value if | |
1018 | the stack pointer alignment is less strict that BIGGEST_ALIGNMENT. | |
1019 | ||
1020 | If we have to align, we must leave space in SIZE for the hole | |
1021 | that might result from the alignment operation. */ | |
1022 | ||
8d998e52 | 1023 | #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (STACK_BOUNDARY) |
515a7242 JW |
1024 | #define MUST_ALIGN 1 |
1025 | #else | |
1026 | #define MUST_ALIGN (STACK_BOUNDARY < BIGGEST_ALIGNMENT) | |
18ca7dab RK |
1027 | #endif |
1028 | ||
515a7242 | 1029 | if (MUST_ALIGN) |
3b998c11 RK |
1030 | { |
1031 | if (GET_CODE (size) == CONST_INT) | |
b1ec3c92 CH |
1032 | size = GEN_INT (INTVAL (size) |
1033 | + (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1)); | |
3b998c11 RK |
1034 | else |
1035 | size = expand_binop (Pmode, add_optab, size, | |
b1ec3c92 CH |
1036 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
1037 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
3b998c11 | 1038 | } |
1d9d04f8 | 1039 | |
18ca7dab RK |
1040 | #ifdef SETJMP_VIA_SAVE_AREA |
1041 | /* If setjmp restores regs from a save area in the stack frame, | |
1042 | avoid clobbering the reg save area. Note that the offset of | |
1043 | virtual_incoming_args_rtx includes the preallocated stack args space. | |
1044 | It would be no problem to clobber that, but it's on the wrong side | |
1045 | of the old save area. */ | |
1046 | { | |
1047 | rtx dynamic_offset | |
1048 | = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx, | |
b1ec3c92 | 1049 | stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN); |
18ca7dab | 1050 | size = expand_binop (Pmode, add_optab, size, dynamic_offset, |
b1ec3c92 | 1051 | NULL_RTX, 1, OPTAB_LIB_WIDEN); |
18ca7dab RK |
1052 | } |
1053 | #endif /* SETJMP_VIA_SAVE_AREA */ | |
1054 | ||
1055 | /* Round the size to a multiple of the required stack alignment. | |
1056 | Since the stack if presumed to be rounded before this allocation, | |
1057 | this will maintain the required alignment. | |
1058 | ||
1059 | If the stack grows downward, we could save an insn by subtracting | |
1060 | SIZE from the stack pointer and then aligning the stack pointer. | |
1061 | The problem with this is that the stack pointer may be unaligned | |
1062 | between the execution of the subtraction and alignment insns and | |
1063 | some machines do not allow this. Even on those that do, some | |
1064 | signal handlers malfunction if a signal should occur between those | |
1065 | insns. Since this is an extremely rare event, we have no reliable | |
1066 | way of knowing which systems have this problem. So we avoid even | |
1067 | momentarily mis-aligning the stack. */ | |
1068 | ||
89d825c9 | 1069 | #ifdef STACK_BOUNDARY |
86b25e81 RS |
1070 | /* If we added a variable amount to SIZE, |
1071 | we can no longer assume it is aligned. */ | |
515a7242 | 1072 | #if !defined (SETJMP_VIA_SAVE_AREA) |
96ec484f | 1073 | if (MUST_ALIGN || known_align % STACK_BOUNDARY != 0) |
34c9156a | 1074 | #endif |
091ad0b9 | 1075 | size = round_push (size); |
89d825c9 | 1076 | #endif |
18ca7dab RK |
1077 | |
1078 | do_pending_stack_adjust (); | |
1079 | ||
edff2491 RK |
1080 | /* If needed, check that we have the required amount of stack. Take into |
1081 | account what has already been checked. */ | |
1082 | if (flag_stack_check && ! STACK_CHECK_BUILTIN) | |
1083 | probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size); | |
1084 | ||
091ad0b9 RK |
1085 | /* Don't use a TARGET that isn't a pseudo. */ |
1086 | if (target == 0 || GET_CODE (target) != REG | |
1087 | || REGNO (target) < FIRST_PSEUDO_REGISTER) | |
18ca7dab RK |
1088 | target = gen_reg_rtx (Pmode); |
1089 | ||
305f22b5 | 1090 | mark_reg_pointer (target, known_align / BITS_PER_UNIT); |
3ad69266 | 1091 | |
18ca7dab RK |
1092 | #ifndef STACK_GROWS_DOWNWARD |
1093 | emit_move_insn (target, virtual_stack_dynamic_rtx); | |
1094 | #endif | |
1095 | ||
1096 | /* Perform the required allocation from the stack. Some systems do | |
1097 | this differently than simply incrementing/decrementing from the | |
1098 | stack pointer. */ | |
1099 | #ifdef HAVE_allocate_stack | |
1100 | if (HAVE_allocate_stack) | |
1101 | { | |
1102 | enum machine_mode mode | |
1103 | = insn_operand_mode[(int) CODE_FOR_allocate_stack][0]; | |
1104 | ||
ea534b63 RK |
1105 | size = convert_modes (mode, ptr_mode, size, 1); |
1106 | ||
18ca7dab RK |
1107 | if (insn_operand_predicate[(int) CODE_FOR_allocate_stack][0] |
1108 | && ! ((*insn_operand_predicate[(int) CODE_FOR_allocate_stack][0]) | |
1109 | (size, mode))) | |
1110 | size = copy_to_mode_reg (mode, size); | |
1111 | ||
1112 | emit_insn (gen_allocate_stack (size)); | |
1113 | } | |
1114 | else | |
1115 | #endif | |
ea534b63 RK |
1116 | { |
1117 | size = convert_modes (Pmode, ptr_mode, size, 1); | |
1118 | anti_adjust_stack (size); | |
1119 | } | |
18ca7dab RK |
1120 | |
1121 | #ifdef STACK_GROWS_DOWNWARD | |
1122 | emit_move_insn (target, virtual_stack_dynamic_rtx); | |
1123 | #endif | |
1124 | ||
515a7242 | 1125 | if (MUST_ALIGN) |
091ad0b9 | 1126 | { |
5244db05 | 1127 | /* CEIL_DIV_EXPR needs to worry about the addition overflowing, |
0f41302f MS |
1128 | but we know it can't. So add ourselves and then do |
1129 | TRUNC_DIV_EXPR. */ | |
0f56a403 | 1130 | target = expand_binop (Pmode, add_optab, target, |
5244db05 RK |
1131 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1), |
1132 | NULL_RTX, 1, OPTAB_LIB_WIDEN); | |
1133 | target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target, | |
b1ec3c92 CH |
1134 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
1135 | NULL_RTX, 1); | |
091ad0b9 | 1136 | target = expand_mult (Pmode, target, |
b1ec3c92 CH |
1137 | GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT), |
1138 | NULL_RTX, 1); | |
091ad0b9 | 1139 | } |
18ca7dab RK |
1140 | |
1141 | /* Some systems require a particular insn to refer to the stack | |
1142 | to make the pages exist. */ | |
1143 | #ifdef HAVE_probe | |
1144 | if (HAVE_probe) | |
1145 | emit_insn (gen_probe ()); | |
1146 | #endif | |
1147 | ||
15fc0026 RK |
1148 | /* Record the new stack level for nonlocal gotos. */ |
1149 | if (nonlocal_goto_handler_slot != 0) | |
1150 | emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX); | |
1151 | ||
18ca7dab RK |
1152 | return target; |
1153 | } | |
1154 | \f | |
edff2491 RK |
1155 | /* Emit one stack probe at ADDRESS, an address within the stack. */ |
1156 | ||
1157 | static void | |
1158 | emit_stack_probe (address) | |
1159 | rtx address; | |
1160 | { | |
1161 | rtx memref = gen_rtx (MEM, word_mode, address); | |
1162 | ||
1163 | MEM_VOLATILE_P (memref) = 1; | |
1164 | ||
1165 | if (STACK_CHECK_PROBE_LOAD) | |
1166 | emit_move_insn (gen_reg_rtx (word_mode), memref); | |
1167 | else | |
1168 | emit_move_insn (memref, const0_rtx); | |
1169 | } | |
1170 | ||
1171 | /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive. | |
1172 | FIRST is a constant and size is a Pmode RTX. These are offsets from the | |
1173 | current stack pointer. STACK_GROWS_DOWNWARD says whether to add or | |
1174 | subtract from the stack. If SIZE is constant, this is done | |
1175 | with a fixed number of probes. Otherwise, we must make a loop. */ | |
1176 | ||
1177 | #ifdef STACK_GROWS_DOWNWARD | |
1178 | #define STACK_GROW_OP MINUS | |
1179 | #else | |
1180 | #define STACK_GROW_OP PLUS | |
1181 | #endif | |
1182 | ||
1183 | void | |
1184 | probe_stack_range (first, size) | |
1185 | HOST_WIDE_INT first; | |
1186 | rtx size; | |
1187 | { | |
1188 | /* First see if we have an insn to check the stack. Use it if so. */ | |
1189 | #ifdef HAVE_check_stack | |
1190 | if (HAVE_check_stack) | |
1191 | { | |
1192 | rtx last_addr = force_operand (gen_rtx (STACK_GROW_OP, Pmode, | |
1193 | stack_pointer_rtx, | |
1194 | plus_constant (size, first)), | |
1195 | NULL_RTX); | |
1196 | ||
1197 | if (insn_operand_predicate[(int) CODE_FOR_check_stack][0] | |
1198 | && ! ((*insn_operand_predicate[(int) CODE_FOR_check_stack][0]) | |
1199 | (last_address, Pmode))) | |
1200 | last_address = copy_to_mode_reg (Pmode, last_address); | |
1201 | ||
1202 | emit_insn (gen_check_stack (last_address)); | |
1203 | return; | |
1204 | } | |
1205 | #endif | |
1206 | ||
1207 | /* If we have to generate explicit probes, see if we have a constant | |
1208 | number of them to generate. If so, that's the easy case. */ | |
1209 | if (GET_CODE (size) == CONST_INT) | |
1210 | { | |
1211 | HOST_WIDE_INT offset; | |
1212 | ||
1213 | /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL | |
1214 | for values of N from 1 until it exceeds LAST. If only one | |
1215 | probe is needed, this will not generate any code. Then probe | |
1216 | at LAST. */ | |
1217 | for (offset = first + STACK_CHECK_PROBE_INTERVAL; | |
1218 | offset < INTVAL (size); | |
1219 | offset = offset + STACK_CHECK_PROBE_INTERVAL) | |
1220 | emit_stack_probe (gen_rtx (STACK_GROW_OP, Pmode, | |
1221 | stack_pointer_rtx, GEN_INT (offset))); | |
1222 | ||
1223 | emit_stack_probe (gen_rtx (STACK_GROW_OP, Pmode, stack_pointer_rtx, | |
1224 | plus_constant (size, first))); | |
1225 | } | |
1226 | ||
1227 | /* In the variable case, do the same as above, but in a loop. We emit loop | |
1228 | notes so that loop optimization can be done. */ | |
1229 | else | |
1230 | { | |
1231 | rtx test_addr | |
1232 | = force_operand (gen_rtx (STACK_GROW_OP, Pmode, stack_pointer_rtx, | |
1233 | GEN_INT (first | |
1234 | + STACK_CHECK_PROBE_INTERVAL)), | |
1235 | NULL_RTX); | |
1236 | rtx last_addr | |
1237 | = force_operand (gen_rtx (STACK_GROW_OP, Pmode, stack_pointer_rtx, | |
1238 | plus_constant (size, first)), | |
1239 | NULL_RTX); | |
1240 | rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL); | |
1241 | rtx loop_lab = gen_label_rtx (); | |
1242 | rtx test_lab = gen_label_rtx (); | |
1243 | rtx end_lab = gen_label_rtx (); | |
1244 | rtx temp; | |
1245 | ||
1246 | if (GET_CODE (test_addr) != REG | |
1247 | || REGNO (test_addr) < FIRST_PSEUDO_REGISTER) | |
1248 | test_addr = force_reg (Pmode, test_addr); | |
1249 | ||
1250 | emit_note (NULL_PTR, NOTE_INSN_LOOP_BEG); | |
1251 | emit_jump (test_lab); | |
1252 | ||
1253 | emit_label (loop_lab); | |
1254 | emit_stack_probe (test_addr); | |
1255 | ||
1256 | emit_note (NULL_PTR, NOTE_INSN_LOOP_CONT); | |
1257 | ||
1258 | #ifdef STACK_GROWS_DOWNWARD | |
1259 | #define CMP_OPCODE GTU | |
1260 | temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr, | |
1261 | 1, OPTAB_WIDEN); | |
1262 | #else | |
1263 | #define CMP_OPCODE LTU | |
1264 | temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr, | |
1265 | 1, OPTAB_WIDEN); | |
1266 | #endif | |
1267 | ||
1268 | if (temp != test_addr) | |
1269 | abort (); | |
1270 | ||
1271 | emit_label (test_lab); | |
1272 | emit_cmp_insn (test_addr, last_addr, CMP_OPCODE, NULL_RTX, Pmode, 1, 0); | |
1273 | emit_jump_insn ((*bcc_gen_fctn[(int) CMP_OPCODE]) (loop_lab)); | |
1274 | emit_jump (end_lab); | |
1275 | emit_note (NULL_PTR, NOTE_INSN_LOOP_END); | |
1276 | emit_label (end_lab); | |
1277 | ||
1278 | emit_stack_probe (last_addr); | |
1279 | } | |
1280 | } | |
1281 | \f | |
18ca7dab RK |
1282 | /* Return an rtx representing the register or memory location |
1283 | in which a scalar value of data type VALTYPE | |
1284 | was returned by a function call to function FUNC. | |
1285 | FUNC is a FUNCTION_DECL node if the precise function is known, | |
1286 | otherwise 0. */ | |
1287 | ||
1288 | rtx | |
1289 | hard_function_value (valtype, func) | |
1290 | tree valtype; | |
1291 | tree func; | |
1292 | { | |
e1a4071f JL |
1293 | rtx val = FUNCTION_VALUE (valtype, func); |
1294 | if (GET_CODE (val) == REG | |
1295 | && GET_MODE (val) == BLKmode) | |
1296 | { | |
1297 | int bytes = int_size_in_bytes (valtype); | |
1298 | enum machine_mode tmpmode; | |
1299 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); | |
1300 | tmpmode != MAX_MACHINE_MODE; | |
1301 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) | |
1302 | { | |
1303 | /* Have we found a large enough mode? */ | |
1304 | if (GET_MODE_SIZE (tmpmode) >= bytes) | |
1305 | break; | |
1306 | } | |
1307 | ||
1308 | /* No suitable mode found. */ | |
1309 | if (tmpmode == MAX_MACHINE_MODE) | |
1310 | abort (); | |
1311 | ||
1312 | PUT_MODE (val, tmpmode); | |
1313 | } | |
1314 | return val; | |
18ca7dab RK |
1315 | } |
1316 | ||
1317 | /* Return an rtx representing the register or memory location | |
1318 | in which a scalar value of mode MODE was returned by a library call. */ | |
1319 | ||
1320 | rtx | |
1321 | hard_libcall_value (mode) | |
1322 | enum machine_mode mode; | |
1323 | { | |
1324 | return LIBCALL_VALUE (mode); | |
1325 | } | |
0c5e217d RS |
1326 | |
1327 | /* Look up the tree code for a given rtx code | |
1328 | to provide the arithmetic operation for REAL_ARITHMETIC. | |
1329 | The function returns an int because the caller may not know | |
1330 | what `enum tree_code' means. */ | |
1331 | ||
1332 | int | |
1333 | rtx_to_tree_code (code) | |
1334 | enum rtx_code code; | |
1335 | { | |
1336 | enum tree_code tcode; | |
1337 | ||
1338 | switch (code) | |
1339 | { | |
1340 | case PLUS: | |
1341 | tcode = PLUS_EXPR; | |
1342 | break; | |
1343 | case MINUS: | |
1344 | tcode = MINUS_EXPR; | |
1345 | break; | |
1346 | case MULT: | |
1347 | tcode = MULT_EXPR; | |
1348 | break; | |
1349 | case DIV: | |
1350 | tcode = RDIV_EXPR; | |
1351 | break; | |
1352 | case SMIN: | |
1353 | tcode = MIN_EXPR; | |
1354 | break; | |
1355 | case SMAX: | |
1356 | tcode = MAX_EXPR; | |
1357 | break; | |
1358 | default: | |
1359 | tcode = LAST_AND_UNUSED_TREE_CODE; | |
1360 | break; | |
1361 | } | |
1362 | return ((int) tcode); | |
1363 | } |