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Commit | Line | Data |
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8c660648 | 1 | /* Move registers around to reduce number of move instructions needed. |
af841dbd | 2 | Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, |
fe9565ed | 3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. |
8c660648 | 4 | |
1322177d | 5 | This file is part of GCC. |
8c660648 | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
8c660648 | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
8c660648 JL |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d | 18 | along with GCC; see the file COPYING. If not, write to the Free |
366ccddb KC |
19 | Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA |
20 | 02110-1301, USA. */ | |
8c660648 JL |
21 | |
22 | ||
23 | /* This module looks for cases where matching constraints would force | |
24 | an instruction to need a reload, and this reload would be a register | |
25 | to register move. It then attempts to change the registers used by the | |
26 | instruction to avoid the move instruction. */ | |
27 | ||
28 | #include "config.h" | |
670ee920 | 29 | #include "system.h" |
4977bab6 ZW |
30 | #include "coretypes.h" |
31 | #include "tm.h" | |
789f983a | 32 | #include "rtl.h" /* stdio.h must precede rtl.h for FFS. */ |
6baf1cc8 | 33 | #include "tm_p.h" |
8c660648 JL |
34 | #include "insn-config.h" |
35 | #include "recog.h" | |
36 | #include "output.h" | |
8c660648 | 37 | #include "regs.h" |
184bb750 R |
38 | #include "hard-reg-set.h" |
39 | #include "flags.h" | |
49ad7cfa | 40 | #include "function.h" |
184bb750 | 41 | #include "expr.h" |
ddc8bed2 | 42 | #include "basic-block.h" |
1a5428f7 | 43 | #include "except.h" |
2e107e9e | 44 | #include "toplev.h" |
8461e984 | 45 | #include "reload.h" |
ef330312 PB |
46 | #include "timevar.h" |
47 | #include "tree-pass.h" | |
184bb750 | 48 | |
595c2290 JH |
49 | |
50 | /* Turn STACK_GROWS_DOWNWARD into a boolean. */ | |
51 | #ifdef STACK_GROWS_DOWNWARD | |
52 | #undef STACK_GROWS_DOWNWARD | |
53 | #define STACK_GROWS_DOWNWARD 1 | |
54 | #else | |
55 | #define STACK_GROWS_DOWNWARD 0 | |
56 | #endif | |
57 | ||
0c20a65f AJ |
58 | static int perhaps_ends_bb_p (rtx); |
59 | static int optimize_reg_copy_1 (rtx, rtx, rtx); | |
60 | static void optimize_reg_copy_2 (rtx, rtx, rtx); | |
61 | static void optimize_reg_copy_3 (rtx, rtx, rtx); | |
62 | static void copy_src_to_dest (rtx, rtx, rtx, int); | |
ddc8bed2 | 63 | static int *regmove_bb_head; |
8c660648 | 64 | |
184bb750 R |
65 | struct match { |
66 | int with[MAX_RECOG_OPERANDS]; | |
67 | enum { READ, WRITE, READWRITE } use[MAX_RECOG_OPERANDS]; | |
68 | int commutative[MAX_RECOG_OPERANDS]; | |
69 | int early_clobber[MAX_RECOG_OPERANDS]; | |
70 | }; | |
71 | ||
0c20a65f AJ |
72 | static rtx discover_flags_reg (void); |
73 | static void mark_flags_life_zones (rtx); | |
74 | static void flags_set_1 (rtx, rtx, void *); | |
75 | ||
76 | static int try_auto_increment (rtx, rtx, rtx, rtx, HOST_WIDE_INT, int); | |
77 | static int find_matches (rtx, struct match *); | |
78 | static void replace_in_call_usage (rtx *, unsigned int, rtx, rtx); | |
10d22567 | 79 | static int fixup_match_1 (rtx, rtx, rtx, rtx, rtx, int, int, int); |
0c20a65f AJ |
80 | static int reg_is_remote_constant_p (rtx, rtx, rtx); |
81 | static int stable_and_no_regs_but_for_p (rtx, rtx, rtx); | |
82 | static int regclass_compatible_p (int, int); | |
83 | static int replacement_quality (rtx); | |
10d22567 | 84 | static int fixup_match_2 (rtx, rtx, rtx, rtx); |
8c660648 | 85 | |
40f03658 | 86 | /* Return nonzero if registers with CLASS1 and CLASS2 can be merged without |
3bb806ed R |
87 | causing too much register allocation problems. */ |
88 | static int | |
0c20a65f | 89 | regclass_compatible_p (int class0, int class1) |
3bb806ed R |
90 | { |
91 | return (class0 == class1 | |
92 | || (reg_class_subset_p (class0, class1) | |
93 | && ! CLASS_LIKELY_SPILLED_P (class0)) | |
94 | || (reg_class_subset_p (class1, class0) | |
95 | && ! CLASS_LIKELY_SPILLED_P (class1))); | |
96 | } | |
97 | ||
8c660648 JL |
98 | /* INC_INSN is an instruction that adds INCREMENT to REG. |
99 | Try to fold INC_INSN as a post/pre in/decrement into INSN. | |
100 | Iff INC_INSN_SET is nonzero, inc_insn has a destination different from src. | |
101 | Return nonzero for success. */ | |
102 | static int | |
0c20a65f AJ |
103 | try_auto_increment (rtx insn, rtx inc_insn, rtx inc_insn_set, rtx reg, |
104 | HOST_WIDE_INT increment, int pre) | |
8c660648 JL |
105 | { |
106 | enum rtx_code inc_code; | |
107 | ||
108 | rtx pset = single_set (insn); | |
109 | if (pset) | |
110 | { | |
111 | /* Can't use the size of SET_SRC, we might have something like | |
112 | (sign_extend:SI (mem:QI ... */ | |
113 | rtx use = find_use_as_address (pset, reg, 0); | |
60e8b9f0 | 114 | if (use != 0 && use != (rtx) (size_t) 1) |
8c660648 JL |
115 | { |
116 | int size = GET_MODE_SIZE (GET_MODE (use)); | |
117 | if (0 | |
940da324 JL |
118 | || (HAVE_POST_INCREMENT |
119 | && pre == 0 && (inc_code = POST_INC, increment == size)) | |
120 | || (HAVE_PRE_INCREMENT | |
121 | && pre == 1 && (inc_code = PRE_INC, increment == size)) | |
122 | || (HAVE_POST_DECREMENT | |
123 | && pre == 0 && (inc_code = POST_DEC, increment == -size)) | |
124 | || (HAVE_PRE_DECREMENT | |
125 | && pre == 1 && (inc_code = PRE_DEC, increment == -size)) | |
184bb750 R |
126 | ) |
127 | { | |
128 | if (inc_insn_set) | |
129 | validate_change | |
174fa2c4 | 130 | (inc_insn, |
184bb750 | 131 | &SET_SRC (inc_insn_set), |
8c660648 | 132 | XEXP (SET_SRC (inc_insn_set), 0), 1); |
184bb750 | 133 | validate_change (insn, &XEXP (use, 0), |
38a448ca | 134 | gen_rtx_fmt_e (inc_code, Pmode, reg), 1); |
184bb750 R |
135 | if (apply_change_group ()) |
136 | { | |
2f33c635 HB |
137 | /* If there is a REG_DEAD note on this insn, we must |
138 | change this not to REG_UNUSED meaning that the register | |
139 | is set, but the value is dead. Failure to do so will | |
0e61db61 | 140 | result in a sched1 dieing -- when it recomputes lifetime |
2f33c635 HB |
141 | information, the number of REG_DEAD notes will have |
142 | changed. */ | |
143 | rtx note = find_reg_note (insn, REG_DEAD, reg); | |
144 | if (note) | |
145 | PUT_MODE (note, REG_UNUSED); | |
146 | ||
184bb750 | 147 | REG_NOTES (insn) |
38a448ca RH |
148 | = gen_rtx_EXPR_LIST (REG_INC, |
149 | reg, REG_NOTES (insn)); | |
184bb750 | 150 | if (! inc_insn_set) |
ca6c03ca | 151 | delete_insn (inc_insn); |
8c660648 | 152 | return 1; |
184bb750 R |
153 | } |
154 | } | |
155 | } | |
156 | } | |
157 | return 0; | |
158 | } | |
dc2cb191 RH |
159 | \f |
160 | /* Determine if the pattern generated by add_optab has a clobber, | |
161 | such as might be issued for a flags hard register. To make the | |
162 | code elsewhere simpler, we handle cc0 in this same framework. | |
163 | ||
164 | Return the register if one was discovered. Return NULL_RTX if | |
165 | if no flags were found. Return pc_rtx if we got confused. */ | |
166 | ||
167 | static rtx | |
0c20a65f | 168 | discover_flags_reg (void) |
dc2cb191 RH |
169 | { |
170 | rtx tmp; | |
cd4b3546 | 171 | tmp = gen_rtx_REG (word_mode, 10000); |
60c81c89 | 172 | tmp = gen_add3_insn (tmp, tmp, const2_rtx); |
dc2cb191 | 173 | |
174fa2c4 | 174 | /* If we get something that isn't a simple set, or a |
dc2cb191 RH |
175 | [(set ..) (clobber ..)], this whole function will go wrong. */ |
176 | if (GET_CODE (tmp) == SET) | |
177 | return NULL_RTX; | |
178 | else if (GET_CODE (tmp) == PARALLEL) | |
179 | { | |
180 | int found; | |
181 | ||
182 | if (XVECLEN (tmp, 0) != 2) | |
183 | return pc_rtx; | |
184 | tmp = XVECEXP (tmp, 0, 1); | |
185 | if (GET_CODE (tmp) != CLOBBER) | |
186 | return pc_rtx; | |
187 | tmp = XEXP (tmp, 0); | |
188 | ||
189 | /* Don't do anything foolish if the md wanted to clobber a | |
190 | scratch or something. We only care about hard regs. | |
191 | Moreover we don't like the notion of subregs of hard regs. */ | |
192 | if (GET_CODE (tmp) == SUBREG | |
f8cfc6aa | 193 | && REG_P (SUBREG_REG (tmp)) |
dc2cb191 RH |
194 | && REGNO (SUBREG_REG (tmp)) < FIRST_PSEUDO_REGISTER) |
195 | return pc_rtx; | |
f8cfc6aa | 196 | found = (REG_P (tmp) && REGNO (tmp) < FIRST_PSEUDO_REGISTER); |
dc2cb191 | 197 | |
dc2cb191 | 198 | return (found ? tmp : NULL_RTX); |
dc2cb191 RH |
199 | } |
200 | ||
201 | return pc_rtx; | |
202 | } | |
203 | ||
204 | /* It is a tedious task identifying when the flags register is live and | |
205 | when it is safe to optimize. Since we process the instruction stream | |
206 | multiple times, locate and record these live zones by marking the | |
174fa2c4 | 207 | mode of the instructions -- |
dc2cb191 RH |
208 | |
209 | QImode is used on the instruction at which the flags becomes live. | |
210 | ||
211 | HImode is used within the range (exclusive) that the flags are | |
212 | live. Thus the user of the flags is not marked. | |
213 | ||
214 | All other instructions are cleared to VOIDmode. */ | |
215 | ||
216 | /* Used to communicate with flags_set_1. */ | |
217 | static rtx flags_set_1_rtx; | |
218 | static int flags_set_1_set; | |
219 | ||
220 | static void | |
0c20a65f | 221 | mark_flags_life_zones (rtx flags) |
dc2cb191 RH |
222 | { |
223 | int flags_regno; | |
224 | int flags_nregs; | |
e0082a72 | 225 | basic_block block; |
dc2cb191 | 226 | |
e7f5b971 RH |
227 | #ifdef HAVE_cc0 |
228 | /* If we found a flags register on a cc0 host, bail. */ | |
229 | if (flags == NULL_RTX) | |
230 | flags = cc0_rtx; | |
231 | else if (flags != cc0_rtx) | |
232 | flags = pc_rtx; | |
233 | #endif | |
174fa2c4 | 234 | |
dc2cb191 RH |
235 | /* Simple cases first: if no flags, clear all modes. If confusing, |
236 | mark the entire function as being in a flags shadow. */ | |
237 | if (flags == NULL_RTX || flags == pc_rtx) | |
238 | { | |
239 | enum machine_mode mode = (flags ? HImode : VOIDmode); | |
240 | rtx insn; | |
8e2e89f7 | 241 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
dc2cb191 RH |
242 | PUT_MODE (insn, mode); |
243 | return; | |
244 | } | |
245 | ||
246 | #ifdef HAVE_cc0 | |
247 | flags_regno = -1; | |
248 | flags_nregs = 1; | |
249 | #else | |
250 | flags_regno = REGNO (flags); | |
66fd46b6 | 251 | flags_nregs = hard_regno_nregs[flags_regno][GET_MODE (flags)]; |
dc2cb191 RH |
252 | #endif |
253 | flags_set_1_rtx = flags; | |
184bb750 | 254 | |
dc2cb191 | 255 | /* Process each basic block. */ |
e0082a72 | 256 | FOR_EACH_BB_REVERSE (block) |
dc2cb191 RH |
257 | { |
258 | rtx insn, end; | |
259 | int live; | |
260 | ||
a813c111 SB |
261 | insn = BB_HEAD (block); |
262 | end = BB_END (block); | |
dc2cb191 RH |
263 | |
264 | /* Look out for the (unlikely) case of flags being live across | |
265 | basic block boundaries. */ | |
266 | live = 0; | |
267 | #ifndef HAVE_cc0 | |
268 | { | |
269 | int i; | |
270 | for (i = 0; i < flags_nregs; ++i) | |
5e2d947c | 271 | live |= REGNO_REG_SET_P (block->il.rtl->global_live_at_start, |
dc2cb191 RH |
272 | flags_regno + i); |
273 | } | |
274 | #endif | |
275 | ||
276 | while (1) | |
277 | { | |
278 | /* Process liveness in reverse order of importance -- | |
279 | alive, death, birth. This lets more important info | |
280 | overwrite the mode of lesser info. */ | |
281 | ||
2c3c49de | 282 | if (INSN_P (insn)) |
dc2cb191 RH |
283 | { |
284 | #ifdef HAVE_cc0 | |
285 | /* In the cc0 case, death is not marked in reg notes, | |
286 | but is instead the mere use of cc0 when it is alive. */ | |
287 | if (live && reg_mentioned_p (cc0_rtx, PATTERN (insn))) | |
288 | live = 0; | |
289 | #else | |
290 | /* In the hard reg case, we watch death notes. */ | |
291 | if (live && find_regno_note (insn, REG_DEAD, flags_regno)) | |
292 | live = 0; | |
293 | #endif | |
294 | PUT_MODE (insn, (live ? HImode : VOIDmode)); | |
295 | ||
d1a6adeb | 296 | /* In either case, birth is denoted simply by its presence |
dc2cb191 RH |
297 | as the destination of a set. */ |
298 | flags_set_1_set = 0; | |
84832317 | 299 | note_stores (PATTERN (insn), flags_set_1, NULL); |
dc2cb191 RH |
300 | if (flags_set_1_set) |
301 | { | |
302 | live = 1; | |
303 | PUT_MODE (insn, QImode); | |
304 | } | |
305 | } | |
306 | else | |
307 | PUT_MODE (insn, (live ? HImode : VOIDmode)); | |
308 | ||
309 | if (insn == end) | |
310 | break; | |
311 | insn = NEXT_INSN (insn); | |
312 | } | |
313 | } | |
314 | } | |
315 | ||
316 | /* A subroutine of mark_flags_life_zones, called through note_stores. */ | |
317 | ||
318 | static void | |
0c20a65f | 319 | flags_set_1 (rtx x, rtx pat, void *data ATTRIBUTE_UNUSED) |
dc2cb191 RH |
320 | { |
321 | if (GET_CODE (pat) == SET | |
322 | && reg_overlap_mentioned_p (x, flags_set_1_rtx)) | |
323 | flags_set_1_set = 1; | |
324 | } | |
325 | \f | |
184bb750 R |
326 | static int *regno_src_regno; |
327 | ||
328 | /* Indicate how good a choice REG (which appears as a source) is to replace | |
329 | a destination register with. The higher the returned value, the better | |
330 | the choice. The main objective is to avoid using a register that is | |
331 | a candidate for tying to a hard register, since the output might in | |
332 | turn be a candidate to be tied to a different hard register. */ | |
95d75019 | 333 | static int |
0c20a65f | 334 | replacement_quality (rtx reg) |
184bb750 R |
335 | { |
336 | int src_regno; | |
337 | ||
338 | /* Bad if this isn't a register at all. */ | |
f8cfc6aa | 339 | if (!REG_P (reg)) |
184bb750 R |
340 | return 0; |
341 | ||
342 | /* If this register is not meant to get a hard register, | |
343 | it is a poor choice. */ | |
344 | if (REG_LIVE_LENGTH (REGNO (reg)) < 0) | |
345 | return 0; | |
346 | ||
347 | src_regno = regno_src_regno[REGNO (reg)]; | |
348 | ||
349 | /* If it was not copied from another register, it is fine. */ | |
350 | if (src_regno < 0) | |
351 | return 3; | |
352 | ||
353 | /* Copied from a hard register? */ | |
354 | if (src_regno < FIRST_PSEUDO_REGISTER) | |
355 | return 1; | |
356 | ||
357 | /* Copied from a pseudo register - not as bad as from a hard register, | |
358 | yet still cumbersome, since the register live length will be lengthened | |
359 | when the registers get tied. */ | |
360 | return 2; | |
361 | } | |
a1c1fdd0 RK |
362 | \f |
363 | /* Return 1 if INSN might end a basic block. */ | |
364 | ||
5671bf27 | 365 | static int perhaps_ends_bb_p (rtx insn) |
a1c1fdd0 RK |
366 | { |
367 | switch (GET_CODE (insn)) | |
368 | { | |
369 | case CODE_LABEL: | |
370 | case JUMP_INSN: | |
371 | /* These always end a basic block. */ | |
372 | return 1; | |
184bb750 | 373 | |
a1c1fdd0 RK |
374 | case CALL_INSN: |
375 | /* A CALL_INSN might be the last insn of a basic block, if it is inside | |
376 | an EH region or if there are nonlocal gotos. Note that this test is | |
377 | very conservative. */ | |
a614d82e RH |
378 | if (nonlocal_goto_handler_labels) |
379 | return 1; | |
5d3cc252 | 380 | /* Fall through. */ |
a1c1fdd0 | 381 | default: |
a614d82e | 382 | return can_throw_internal (insn); |
a1c1fdd0 RK |
383 | } |
384 | } | |
385 | \f | |
1230327b R |
386 | /* INSN is a copy from SRC to DEST, both registers, and SRC does not die |
387 | in INSN. | |
388 | ||
389 | Search forward to see if SRC dies before either it or DEST is modified, | |
390 | but don't scan past the end of a basic block. If so, we can replace SRC | |
174fa2c4 | 391 | with DEST and let SRC die in INSN. |
1230327b R |
392 | |
393 | This will reduce the number of registers live in that range and may enable | |
394 | DEST to be tied to SRC, thus often saving one register in addition to a | |
395 | register-register copy. */ | |
396 | ||
397 | static int | |
0c20a65f | 398 | optimize_reg_copy_1 (rtx insn, rtx dest, rtx src) |
1230327b R |
399 | { |
400 | rtx p, q; | |
401 | rtx note; | |
402 | rtx dest_death = 0; | |
403 | int sregno = REGNO (src); | |
404 | int dregno = REGNO (dest); | |
405 | ||
dc297297 | 406 | /* We don't want to mess with hard regs if register classes are small. */ |
1230327b R |
407 | if (sregno == dregno |
408 | || (SMALL_REGISTER_CLASSES | |
409 | && (sregno < FIRST_PSEUDO_REGISTER | |
410 | || dregno < FIRST_PSEUDO_REGISTER)) | |
411 | /* We don't see all updates to SP if they are in an auto-inc memory | |
412 | reference, so we must disallow this optimization on them. */ | |
413 | || sregno == STACK_POINTER_REGNUM || dregno == STACK_POINTER_REGNUM) | |
414 | return 0; | |
415 | ||
416 | for (p = NEXT_INSN (insn); p; p = NEXT_INSN (p)) | |
417 | { | |
7bf825d2 | 418 | /* ??? We can't scan past the end of a basic block without updating |
a1c1fdd0 RK |
419 | the register lifetime info (REG_DEAD/basic_block_live_at_start). */ |
420 | if (perhaps_ends_bb_p (p)) | |
7bf825d2 | 421 | break; |
a1c1fdd0 | 422 | else if (! INSN_P (p)) |
1230327b R |
423 | continue; |
424 | ||
425 | if (reg_set_p (src, p) || reg_set_p (dest, p) | |
51928907 HPN |
426 | /* If SRC is an asm-declared register, it must not be replaced |
427 | in any asm. Unfortunately, the REG_EXPR tree for the asm | |
428 | variable may be absent in the SRC rtx, so we can't check the | |
429 | actual register declaration easily (the asm operand will have | |
430 | it, though). To avoid complicating the test for a rare case, | |
431 | we just don't perform register replacement for a hard reg | |
432 | mentioned in an asm. */ | |
433 | || (sregno < FIRST_PSEUDO_REGISTER | |
434 | && asm_noperands (PATTERN (p)) >= 0 | |
435 | && reg_overlap_mentioned_p (src, PATTERN (p))) | |
97b69e51 DJ |
436 | /* Don't change hard registers used by a call. */ |
437 | || (CALL_P (p) && sregno < FIRST_PSEUDO_REGISTER | |
438 | && find_reg_fusage (p, USE, src)) | |
1230327b R |
439 | /* Don't change a USE of a register. */ |
440 | || (GET_CODE (PATTERN (p)) == USE | |
441 | && reg_overlap_mentioned_p (src, XEXP (PATTERN (p), 0)))) | |
442 | break; | |
443 | ||
444 | /* See if all of SRC dies in P. This test is slightly more | |
445 | conservative than it needs to be. */ | |
446 | if ((note = find_regno_note (p, REG_DEAD, sregno)) != 0 | |
447 | && GET_MODE (XEXP (note, 0)) == GET_MODE (src)) | |
448 | { | |
449 | int failed = 0; | |
1230327b | 450 | int d_length = 0; |
89098dc1 | 451 | int s_length = 0; |
1230327b | 452 | int d_n_calls = 0; |
89098dc1 | 453 | int s_n_calls = 0; |
1230327b R |
454 | |
455 | /* We can do the optimization. Scan forward from INSN again, | |
456 | replacing regs as we go. Set FAILED if a replacement can't | |
457 | be done. In that case, we can't move the death note for SRC. | |
458 | This should be rare. */ | |
459 | ||
460 | /* Set to stop at next insn. */ | |
461 | for (q = next_real_insn (insn); | |
462 | q != next_real_insn (p); | |
463 | q = next_real_insn (q)) | |
464 | { | |
465 | if (reg_overlap_mentioned_p (src, PATTERN (q))) | |
466 | { | |
467 | /* If SRC is a hard register, we might miss some | |
468 | overlapping registers with validate_replace_rtx, | |
469 | so we would have to undo it. We can't if DEST is | |
470 | present in the insn, so fail in that combination | |
471 | of cases. */ | |
472 | if (sregno < FIRST_PSEUDO_REGISTER | |
473 | && reg_mentioned_p (dest, PATTERN (q))) | |
474 | failed = 1; | |
475 | ||
476 | /* Replace all uses and make sure that the register | |
477 | isn't still present. */ | |
478 | else if (validate_replace_rtx (src, dest, q) | |
479 | && (sregno >= FIRST_PSEUDO_REGISTER | |
480 | || ! reg_overlap_mentioned_p (src, | |
481 | PATTERN (q)))) | |
1b7c4a37 | 482 | ; |
1230327b R |
483 | else |
484 | { | |
485 | validate_replace_rtx (dest, src, q); | |
486 | failed = 1; | |
487 | } | |
488 | } | |
489 | ||
89098dc1 JL |
490 | /* For SREGNO, count the total number of insns scanned. |
491 | For DREGNO, count the total number of insns scanned after | |
492 | passing the death note for DREGNO. */ | |
493 | s_length++; | |
1230327b R |
494 | if (dest_death) |
495 | d_length++; | |
496 | ||
497 | /* If the insn in which SRC dies is a CALL_INSN, don't count it | |
498 | as a call that has been crossed. Otherwise, count it. */ | |
4b4bf941 | 499 | if (q != p && CALL_P (q)) |
1230327b | 500 | { |
89098dc1 JL |
501 | /* Similarly, total calls for SREGNO, total calls beyond |
502 | the death note for DREGNO. */ | |
503 | s_n_calls++; | |
1230327b R |
504 | if (dest_death) |
505 | d_n_calls++; | |
506 | } | |
507 | ||
508 | /* If DEST dies here, remove the death note and save it for | |
509 | later. Make sure ALL of DEST dies here; again, this is | |
510 | overly conservative. */ | |
511 | if (dest_death == 0 | |
512 | && (dest_death = find_regno_note (q, REG_DEAD, dregno)) != 0) | |
513 | { | |
514 | if (GET_MODE (XEXP (dest_death, 0)) != GET_MODE (dest)) | |
515 | failed = 1, dest_death = 0; | |
516 | else | |
517 | remove_note (q, dest_death); | |
518 | } | |
519 | } | |
520 | ||
521 | if (! failed) | |
522 | { | |
89098dc1 JL |
523 | /* These counters need to be updated if and only if we are |
524 | going to move the REG_DEAD note. */ | |
1230327b R |
525 | if (sregno >= FIRST_PSEUDO_REGISTER) |
526 | { | |
527 | if (REG_LIVE_LENGTH (sregno) >= 0) | |
528 | { | |
89098dc1 | 529 | REG_LIVE_LENGTH (sregno) -= s_length; |
1230327b R |
530 | /* REG_LIVE_LENGTH is only an approximation after |
531 | combine if sched is not run, so make sure that we | |
532 | still have a reasonable value. */ | |
533 | if (REG_LIVE_LENGTH (sregno) < 2) | |
534 | REG_LIVE_LENGTH (sregno) = 2; | |
535 | } | |
536 | ||
89098dc1 | 537 | REG_N_CALLS_CROSSED (sregno) -= s_n_calls; |
1230327b R |
538 | } |
539 | ||
540 | /* Move death note of SRC from P to INSN. */ | |
541 | remove_note (p, note); | |
542 | XEXP (note, 1) = REG_NOTES (insn); | |
543 | REG_NOTES (insn) = note; | |
544 | } | |
545 | ||
124d535f JW |
546 | /* DEST is also dead if INSN has a REG_UNUSED note for DEST. */ |
547 | if (! dest_death | |
548 | && (dest_death = find_regno_note (insn, REG_UNUSED, dregno))) | |
549 | { | |
550 | PUT_REG_NOTE_KIND (dest_death, REG_DEAD); | |
551 | remove_note (insn, dest_death); | |
552 | } | |
553 | ||
1230327b R |
554 | /* Put death note of DEST on P if we saw it die. */ |
555 | if (dest_death) | |
556 | { | |
557 | XEXP (dest_death, 1) = REG_NOTES (p); | |
558 | REG_NOTES (p) = dest_death; | |
89098dc1 JL |
559 | |
560 | if (dregno >= FIRST_PSEUDO_REGISTER) | |
561 | { | |
562 | /* If and only if we are moving the death note for DREGNO, | |
563 | then we need to update its counters. */ | |
564 | if (REG_LIVE_LENGTH (dregno) >= 0) | |
565 | REG_LIVE_LENGTH (dregno) += d_length; | |
566 | REG_N_CALLS_CROSSED (dregno) += d_n_calls; | |
567 | } | |
1230327b R |
568 | } |
569 | ||
570 | return ! failed; | |
571 | } | |
572 | ||
573 | /* If SRC is a hard register which is set or killed in some other | |
574 | way, we can't do this optimization. */ | |
575 | else if (sregno < FIRST_PSEUDO_REGISTER | |
576 | && dead_or_set_p (p, src)) | |
577 | break; | |
578 | } | |
579 | return 0; | |
580 | } | |
581 | \f | |
582 | /* INSN is a copy of SRC to DEST, in which SRC dies. See if we now have | |
583 | a sequence of insns that modify DEST followed by an insn that sets | |
584 | SRC to DEST in which DEST dies, with no prior modification of DEST. | |
585 | (There is no need to check if the insns in between actually modify | |
586 | DEST. We should not have cases where DEST is not modified, but | |
587 | the optimization is safe if no such modification is detected.) | |
588 | In that case, we can replace all uses of DEST, starting with INSN and | |
589 | ending with the set of SRC to DEST, with SRC. We do not do this | |
590 | optimization if a CALL_INSN is crossed unless SRC already crosses a | |
591 | call or if DEST dies before the copy back to SRC. | |
592 | ||
593 | It is assumed that DEST and SRC are pseudos; it is too complicated to do | |
594 | this for hard registers since the substitutions we may make might fail. */ | |
595 | ||
596 | static void | |
0c20a65f | 597 | optimize_reg_copy_2 (rtx insn, rtx dest, rtx src) |
1230327b R |
598 | { |
599 | rtx p, q; | |
600 | rtx set; | |
601 | int sregno = REGNO (src); | |
602 | int dregno = REGNO (dest); | |
603 | ||
604 | for (p = NEXT_INSN (insn); p; p = NEXT_INSN (p)) | |
605 | { | |
7bf825d2 | 606 | /* ??? We can't scan past the end of a basic block without updating |
a1c1fdd0 RK |
607 | the register lifetime info (REG_DEAD/basic_block_live_at_start). */ |
608 | if (perhaps_ends_bb_p (p)) | |
7bf825d2 | 609 | break; |
a1c1fdd0 | 610 | else if (! INSN_P (p)) |
1230327b R |
611 | continue; |
612 | ||
613 | set = single_set (p); | |
614 | if (set && SET_SRC (set) == dest && SET_DEST (set) == src | |
615 | && find_reg_note (p, REG_DEAD, dest)) | |
616 | { | |
617 | /* We can do the optimization. Scan forward from INSN again, | |
618 | replacing regs as we go. */ | |
619 | ||
620 | /* Set to stop at next insn. */ | |
621 | for (q = insn; q != NEXT_INSN (p); q = NEXT_INSN (q)) | |
2c3c49de | 622 | if (INSN_P (q)) |
1230327b R |
623 | { |
624 | if (reg_mentioned_p (dest, PATTERN (q))) | |
1b7c4a37 | 625 | PATTERN (q) = replace_rtx (PATTERN (q), dest, src); |
1230327b R |
626 | |
627 | ||
4b4bf941 | 628 | if (CALL_P (q)) |
1230327b R |
629 | { |
630 | REG_N_CALLS_CROSSED (dregno)--; | |
631 | REG_N_CALLS_CROSSED (sregno)++; | |
632 | } | |
633 | } | |
634 | ||
635 | remove_note (p, find_reg_note (p, REG_DEAD, dest)); | |
636 | REG_N_DEATHS (dregno)--; | |
637 | remove_note (insn, find_reg_note (insn, REG_DEAD, src)); | |
638 | REG_N_DEATHS (sregno)--; | |
639 | return; | |
640 | } | |
641 | ||
642 | if (reg_set_p (src, p) | |
643 | || find_reg_note (p, REG_DEAD, dest) | |
4b4bf941 | 644 | || (CALL_P (p) && REG_N_CALLS_CROSSED (sregno) == 0)) |
1230327b R |
645 | break; |
646 | } | |
647 | } | |
184bb750 R |
648 | /* INSN is a ZERO_EXTEND or SIGN_EXTEND of SRC to DEST. |
649 | Look if SRC dies there, and if it is only set once, by loading | |
3d042e77 | 650 | it from memory. If so, try to incorporate the zero/sign extension |
184bb750 R |
651 | into the memory read, change SRC to the mode of DEST, and alter |
652 | the remaining accesses to use the appropriate SUBREG. This allows | |
653 | SRC and DEST to be tied later. */ | |
654 | static void | |
0c20a65f | 655 | optimize_reg_copy_3 (rtx insn, rtx dest, rtx src) |
184bb750 R |
656 | { |
657 | rtx src_reg = XEXP (src, 0); | |
658 | int src_no = REGNO (src_reg); | |
659 | int dst_no = REGNO (dest); | |
15ee342b | 660 | rtx p, set; |
184bb750 R |
661 | enum machine_mode old_mode; |
662 | ||
663 | if (src_no < FIRST_PSEUDO_REGISTER | |
664 | || dst_no < FIRST_PSEUDO_REGISTER | |
665 | || ! find_reg_note (insn, REG_DEAD, src_reg) | |
6d80a854 | 666 | || REG_N_DEATHS (src_no) != 1 |
184bb750 R |
667 | || REG_N_SETS (src_no) != 1) |
668 | return; | |
9c07e479 | 669 | for (p = PREV_INSN (insn); p && ! reg_set_p (src_reg, p); p = PREV_INSN (p)) |
a1c1fdd0 RK |
670 | /* ??? We can't scan past the end of a basic block without updating |
671 | the register lifetime info (REG_DEAD/basic_block_live_at_start). */ | |
672 | if (perhaps_ends_bb_p (p)) | |
673 | break; | |
7bf825d2 | 674 | |
9c07e479 BK |
675 | if (! p) |
676 | return; | |
677 | ||
184bb750 | 678 | if (! (set = single_set (p)) |
3c0cb5de | 679 | || !MEM_P (SET_SRC (set)) |
4fb3cbd7 BS |
680 | /* If there's a REG_EQUIV note, this must be an insn that loads an |
681 | argument. Prefer keeping the note over doing this optimization. */ | |
682 | || find_reg_note (p, REG_EQUIV, NULL_RTX) | |
184bb750 R |
683 | || SET_DEST (set) != src_reg) |
684 | return; | |
937e37cc | 685 | |
14b493d6 | 686 | /* Be conservative: although this optimization is also valid for |
972b320c R |
687 | volatile memory references, that could cause trouble in later passes. */ |
688 | if (MEM_VOLATILE_P (SET_SRC (set))) | |
689 | return; | |
690 | ||
937e37cc JL |
691 | /* Do not use a SUBREG to truncate from one mode to another if truncation |
692 | is not a nop. */ | |
693 | if (GET_MODE_BITSIZE (GET_MODE (src_reg)) <= GET_MODE_BITSIZE (GET_MODE (src)) | |
694 | && !TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (GET_MODE (src)), | |
695 | GET_MODE_BITSIZE (GET_MODE (src_reg)))) | |
696 | return; | |
697 | ||
184bb750 R |
698 | old_mode = GET_MODE (src_reg); |
699 | PUT_MODE (src_reg, GET_MODE (src)); | |
700 | XEXP (src, 0) = SET_SRC (set); | |
e757da5e JL |
701 | |
702 | /* Include this change in the group so that it's easily undone if | |
703 | one of the changes in the group is invalid. */ | |
704 | validate_change (p, &SET_SRC (set), src, 1); | |
705 | ||
706 | /* Now walk forward making additional replacements. We want to be able | |
707 | to undo all the changes if a later substitution fails. */ | |
184bb750 R |
708 | while (p = NEXT_INSN (p), p != insn) |
709 | { | |
2c3c49de | 710 | if (! INSN_P (p)) |
184bb750 | 711 | continue; |
e757da5e | 712 | |
2067c116 | 713 | /* Make a tentative change. */ |
15ee342b EB |
714 | validate_replace_rtx_group (src_reg, |
715 | gen_lowpart_SUBREG (old_mode, src_reg), | |
716 | p); | |
e757da5e JL |
717 | } |
718 | ||
719 | validate_replace_rtx_group (src, src_reg, insn); | |
720 | ||
721 | /* Now see if all the changes are valid. */ | |
722 | if (! apply_change_group ()) | |
723 | { | |
724 | /* One or more changes were no good. Back out everything. */ | |
725 | PUT_MODE (src_reg, old_mode); | |
726 | XEXP (src, 0) = src_reg; | |
184bb750 | 727 | } |
4fb3cbd7 BS |
728 | else |
729 | { | |
730 | rtx note = find_reg_note (p, REG_EQUAL, NULL_RTX); | |
731 | if (note) | |
732 | remove_note (p, note); | |
733 | } | |
184bb750 R |
734 | } |
735 | ||
ddc8bed2 MM |
736 | \f |
737 | /* If we were not able to update the users of src to use dest directly, try | |
738 | instead moving the value to dest directly before the operation. */ | |
739 | ||
cab634f2 | 740 | static void |
0c20a65f | 741 | copy_src_to_dest (rtx insn, rtx src, rtx dest, int old_max_uid) |
ddc8bed2 MM |
742 | { |
743 | rtx seq; | |
744 | rtx link; | |
745 | rtx next; | |
746 | rtx set; | |
747 | rtx move_insn; | |
748 | rtx *p_insn_notes; | |
749 | rtx *p_move_notes; | |
ddc8bed2 MM |
750 | int src_regno; |
751 | int dest_regno; | |
752 | int bb; | |
753 | int insn_uid; | |
754 | int move_uid; | |
755 | ||
756 | /* A REG_LIVE_LENGTH of -1 indicates the register is equivalent to a constant | |
757 | or memory location and is used infrequently; a REG_LIVE_LENGTH of -2 is | |
758 | parameter when there is no frame pointer that is not allocated a register. | |
759 | For now, we just reject them, rather than incrementing the live length. */ | |
760 | ||
f8cfc6aa | 761 | if (REG_P (src) |
3ac3da71 | 762 | && REG_LIVE_LENGTH (REGNO (src)) > 0 |
f8cfc6aa | 763 | && REG_P (dest) |
3ac3da71 | 764 | && REG_LIVE_LENGTH (REGNO (dest)) > 0 |
ddc8bed2 | 765 | && (set = single_set (insn)) != NULL_RTX |
9d2106a4 R |
766 | && !reg_mentioned_p (dest, SET_SRC (set)) |
767 | && GET_MODE (src) == GET_MODE (dest)) | |
ddc8bed2 | 768 | { |
1a8fca8a R |
769 | int old_num_regs = reg_rtx_no; |
770 | ||
ddc8bed2 MM |
771 | /* Generate the src->dest move. */ |
772 | start_sequence (); | |
773 | emit_move_insn (dest, src); | |
2f937369 | 774 | seq = get_insns (); |
ddc8bed2 | 775 | end_sequence (); |
1a8fca8a R |
776 | /* If this sequence uses new registers, we may not use it. */ |
777 | if (old_num_regs != reg_rtx_no | |
778 | || ! validate_replace_rtx (src, dest, insn)) | |
779 | { | |
780 | /* We have to restore reg_rtx_no to its old value, lest | |
781 | recompute_reg_usage will try to compute the usage of the | |
782 | new regs, yet reg_n_info is not valid for them. */ | |
783 | reg_rtx_no = old_num_regs; | |
784 | return; | |
785 | } | |
ddc8bed2 MM |
786 | emit_insn_before (seq, insn); |
787 | move_insn = PREV_INSN (insn); | |
788 | p_move_notes = ®_NOTES (move_insn); | |
789 | p_insn_notes = ®_NOTES (insn); | |
790 | ||
3eae4643 | 791 | /* Move any notes mentioning src to the move instruction. */ |
ddc8bed2 MM |
792 | for (link = REG_NOTES (insn); link != NULL_RTX; link = next) |
793 | { | |
794 | next = XEXP (link, 1); | |
795 | if (XEXP (link, 0) == src) | |
796 | { | |
797 | *p_move_notes = link; | |
798 | p_move_notes = &XEXP (link, 1); | |
799 | } | |
800 | else | |
801 | { | |
802 | *p_insn_notes = link; | |
803 | p_insn_notes = &XEXP (link, 1); | |
804 | } | |
805 | } | |
806 | ||
807 | *p_move_notes = NULL_RTX; | |
808 | *p_insn_notes = NULL_RTX; | |
809 | ||
3eae4643 | 810 | /* Is the insn the head of a basic block? If so extend it. */ |
ddc8bed2 MM |
811 | insn_uid = INSN_UID (insn); |
812 | move_uid = INSN_UID (move_insn); | |
78dd9906 | 813 | if (insn_uid < old_max_uid) |
ddc8bed2 | 814 | { |
78dd9906 R |
815 | bb = regmove_bb_head[insn_uid]; |
816 | if (bb >= 0) | |
817 | { | |
a813c111 | 818 | BB_HEAD (BASIC_BLOCK (bb)) = move_insn; |
78dd9906 R |
819 | regmove_bb_head[insn_uid] = -1; |
820 | } | |
ddc8bed2 MM |
821 | } |
822 | ||
823 | /* Update the various register tables. */ | |
824 | dest_regno = REGNO (dest); | |
1b7c4a37 | 825 | REG_N_SETS (dest_regno) ++; |
ddc8bed2 MM |
826 | REG_LIVE_LENGTH (dest_regno)++; |
827 | if (REGNO_FIRST_UID (dest_regno) == insn_uid) | |
828 | REGNO_FIRST_UID (dest_regno) = move_uid; | |
829 | ||
830 | src_regno = REGNO (src); | |
831 | if (! find_reg_note (move_insn, REG_DEAD, src)) | |
832 | REG_LIVE_LENGTH (src_regno)++; | |
833 | ||
834 | if (REGNO_FIRST_UID (src_regno) == insn_uid) | |
835 | REGNO_FIRST_UID (src_regno) = move_uid; | |
836 | ||
837 | if (REGNO_LAST_UID (src_regno) == insn_uid) | |
838 | REGNO_LAST_UID (src_regno) = move_uid; | |
ddc8bed2 MM |
839 | } |
840 | } | |
841 | ||
842 | \f | |
184bb750 R |
843 | /* Return whether REG is set in only one location, and is set to a |
844 | constant, but is set in a different basic block from INSN (an | |
845 | instructions which uses REG). In this case REG is equivalent to a | |
846 | constant, and we don't want to break that equivalence, because that | |
847 | may increase register pressure and make reload harder. If REG is | |
848 | set in the same basic block as INSN, we don't worry about it, | |
849 | because we'll probably need a register anyhow (??? but what if REG | |
850 | is used in a different basic block as well as this one?). FIRST is | |
851 | the first insn in the function. */ | |
852 | ||
853 | static int | |
0c20a65f | 854 | reg_is_remote_constant_p (rtx reg, rtx insn, rtx first) |
184bb750 | 855 | { |
b3694847 | 856 | rtx p; |
184bb750 R |
857 | |
858 | if (REG_N_SETS (REGNO (reg)) != 1) | |
859 | return 0; | |
860 | ||
861 | /* Look for the set. */ | |
0621d71a | 862 | for (p = BB_HEAD (BLOCK_FOR_INSN (insn)); p != insn; p = NEXT_INSN (p)) |
184bb750 R |
863 | { |
864 | rtx s; | |
865 | ||
0621d71a | 866 | if (!INSN_P (p)) |
184bb750 | 867 | continue; |
0621d71a | 868 | s = single_set (p); |
184bb750 | 869 | if (s != 0 |
f8cfc6aa | 870 | && REG_P (SET_DEST (s)) |
184bb750 R |
871 | && REGNO (SET_DEST (s)) == REGNO (reg)) |
872 | { | |
873 | /* The register is set in the same basic block. */ | |
874 | return 0; | |
875 | } | |
876 | } | |
877 | ||
878 | for (p = first; p && p != insn; p = NEXT_INSN (p)) | |
879 | { | |
880 | rtx s; | |
881 | ||
2c3c49de | 882 | if (! INSN_P (p)) |
184bb750 R |
883 | continue; |
884 | s = single_set (p); | |
885 | if (s != 0 | |
f8cfc6aa | 886 | && REG_P (SET_DEST (s)) |
184bb750 R |
887 | && REGNO (SET_DEST (s)) == REGNO (reg)) |
888 | { | |
889 | /* This is the instruction which sets REG. If there is a | |
890 | REG_EQUAL note, then REG is equivalent to a constant. */ | |
891 | if (find_reg_note (p, REG_EQUAL, NULL_RTX)) | |
892 | return 1; | |
893 | return 0; | |
894 | } | |
895 | } | |
896 | ||
897 | return 0; | |
898 | } | |
899 | ||
b1a7d591 JW |
900 | /* INSN is adding a CONST_INT to a REG. We search backwards looking for |
901 | another add immediate instruction with the same source and dest registers, | |
902 | and if we find one, we change INSN to an increment, and return 1. If | |
903 | no changes are made, we return 0. | |
904 | ||
905 | This changes | |
906 | (set (reg100) (plus reg1 offset1)) | |
907 | ... | |
908 | (set (reg100) (plus reg1 offset2)) | |
909 | to | |
910 | (set (reg100) (plus reg1 offset1)) | |
911 | ... | |
912 | (set (reg100) (plus reg100 offset2-offset1)) */ | |
913 | ||
914 | /* ??? What does this comment mean? */ | |
14b493d6 | 915 | /* cse disrupts preincrement / postdecrement sequences when it finds a |
184bb750 | 916 | hard register as ultimate source, like the frame pointer. */ |
b1a7d591 | 917 | |
95d75019 | 918 | static int |
10d22567 | 919 | fixup_match_2 (rtx insn, rtx dst, rtx src, rtx offset) |
184bb750 R |
920 | { |
921 | rtx p, dst_death = 0; | |
922 | int length, num_calls = 0; | |
923 | ||
924 | /* If SRC dies in INSN, we'd have to move the death note. This is | |
925 | considered to be very unlikely, so we just skip the optimization | |
926 | in this case. */ | |
927 | if (find_regno_note (insn, REG_DEAD, REGNO (src))) | |
928 | return 0; | |
929 | ||
930 | /* Scan backward to find the first instruction that sets DST. */ | |
931 | ||
932 | for (length = 0, p = PREV_INSN (insn); p; p = PREV_INSN (p)) | |
933 | { | |
934 | rtx pset; | |
935 | ||
7bf825d2 | 936 | /* ??? We can't scan past the end of a basic block without updating |
a1c1fdd0 RK |
937 | the register lifetime info (REG_DEAD/basic_block_live_at_start). */ |
938 | if (perhaps_ends_bb_p (p)) | |
7bf825d2 | 939 | break; |
a1c1fdd0 | 940 | else if (! INSN_P (p)) |
a6a2274a | 941 | continue; |
184bb750 | 942 | |
7bf825d2 JW |
943 | if (find_regno_note (p, REG_DEAD, REGNO (dst))) |
944 | dst_death = p; | |
945 | if (! dst_death) | |
946 | length++; | |
184bb750 R |
947 | |
948 | pset = single_set (p); | |
949 | if (pset && SET_DEST (pset) == dst | |
950 | && GET_CODE (SET_SRC (pset)) == PLUS | |
951 | && XEXP (SET_SRC (pset), 0) == src | |
952 | && GET_CODE (XEXP (SET_SRC (pset), 1)) == CONST_INT) | |
a6a2274a | 953 | { |
184bb750 R |
954 | HOST_WIDE_INT newconst |
955 | = INTVAL (offset) - INTVAL (XEXP (SET_SRC (pset), 1)); | |
1a29f703 R |
956 | rtx add = gen_add3_insn (dst, dst, GEN_INT (newconst)); |
957 | ||
958 | if (add && validate_change (insn, &PATTERN (insn), add, 0)) | |
184bb750 R |
959 | { |
960 | /* Remove the death note for DST from DST_DEATH. */ | |
961 | if (dst_death) | |
962 | { | |
963 | remove_death (REGNO (dst), dst_death); | |
964 | REG_LIVE_LENGTH (REGNO (dst)) += length; | |
965 | REG_N_CALLS_CROSSED (REGNO (dst)) += num_calls; | |
966 | } | |
967 | ||
10d22567 ZD |
968 | if (dump_file) |
969 | fprintf (dump_file, | |
184bb750 R |
970 | "Fixed operand of insn %d.\n", |
971 | INSN_UID (insn)); | |
972 | ||
973 | #ifdef AUTO_INC_DEC | |
974 | for (p = PREV_INSN (insn); p; p = PREV_INSN (p)) | |
975 | { | |
4b4bf941 JQ |
976 | if (LABEL_P (p) |
977 | || JUMP_P (p)) | |
184bb750 | 978 | break; |
2c3c49de | 979 | if (! INSN_P (p)) |
e27a5106 | 980 | continue; |
184bb750 R |
981 | if (reg_overlap_mentioned_p (dst, PATTERN (p))) |
982 | { | |
983 | if (try_auto_increment (p, insn, 0, dst, newconst, 0)) | |
984 | return 1; | |
985 | break; | |
986 | } | |
987 | } | |
988 | for (p = NEXT_INSN (insn); p; p = NEXT_INSN (p)) | |
989 | { | |
4b4bf941 JQ |
990 | if (LABEL_P (p) |
991 | || JUMP_P (p)) | |
184bb750 | 992 | break; |
2c3c49de | 993 | if (! INSN_P (p)) |
8543c01e | 994 | continue; |
184bb750 R |
995 | if (reg_overlap_mentioned_p (dst, PATTERN (p))) |
996 | { | |
997 | try_auto_increment (p, insn, 0, dst, newconst, 1); | |
998 | break; | |
999 | } | |
1000 | } | |
1001 | #endif | |
1002 | return 1; | |
1003 | } | |
a6a2274a | 1004 | } |
184bb750 R |
1005 | |
1006 | if (reg_set_p (dst, PATTERN (p))) | |
a6a2274a | 1007 | break; |
184bb750 R |
1008 | |
1009 | /* If we have passed a call instruction, and the | |
1010 | pseudo-reg SRC is not already live across a call, | |
1011 | then don't perform the optimization. */ | |
1012 | /* reg_set_p is overly conservative for CALL_INSNS, thinks that all | |
1013 | hard regs are clobbered. Thus, we only use it for src for | |
1014 | non-call insns. */ | |
4b4bf941 | 1015 | if (CALL_P (p)) |
a6a2274a | 1016 | { |
184bb750 R |
1017 | if (! dst_death) |
1018 | num_calls++; | |
1019 | ||
a6a2274a KH |
1020 | if (REG_N_CALLS_CROSSED (REGNO (src)) == 0) |
1021 | break; | |
184bb750 R |
1022 | |
1023 | if (call_used_regs [REGNO (dst)] | |
1024 | || find_reg_fusage (p, CLOBBER, dst)) | |
1025 | break; | |
a6a2274a | 1026 | } |
184bb750 | 1027 | else if (reg_set_p (src, PATTERN (p))) |
a6a2274a | 1028 | break; |
8c660648 | 1029 | } |
184bb750 | 1030 | |
8c660648 JL |
1031 | return 0; |
1032 | } | |
8c660648 | 1033 | |
3721581a JJ |
1034 | /* Main entry for the register move optimization. |
1035 | F is the first instruction. | |
1036 | NREGS is one plus the highest pseudo-reg number used in the instruction. | |
1037 | REGMOVE_DUMP_FILE is a stream for output of a trace of actions taken | |
1038 | (or 0 if none should be output). */ | |
1039 | ||
fe3c3571 | 1040 | static void |
10d22567 | 1041 | regmove_optimize (rtx f, int nregs) |
8c660648 | 1042 | { |
961d4119 | 1043 | int old_max_uid = get_max_uid (); |
8c660648 | 1044 | rtx insn; |
184bb750 | 1045 | struct match match; |
8c660648 | 1046 | int pass; |
3bb806ed | 1047 | int i; |
ddc8bed2 | 1048 | rtx copy_src, copy_dst; |
e0082a72 | 1049 | basic_block bb; |
184bb750 | 1050 | |
a614d82e RH |
1051 | /* ??? Hack. Regmove doesn't examine the CFG, and gets mightily |
1052 | confused by non-call exceptions ending blocks. */ | |
1053 | if (flag_non_call_exceptions) | |
1054 | return; | |
1055 | ||
dc2cb191 | 1056 | /* Find out where a potential flags register is live, and so that we |
14b493d6 | 1057 | can suppress some optimizations in those zones. */ |
dc2cb191 RH |
1058 | mark_flags_life_zones (discover_flags_reg ()); |
1059 | ||
5ed6ace5 | 1060 | regno_src_regno = XNEWVEC (int, nregs); |
3bb806ed | 1061 | for (i = nregs; --i >= 0; ) regno_src_regno[i] = -1; |
8c660648 | 1062 | |
5ed6ace5 | 1063 | regmove_bb_head = XNEWVEC (int, old_max_uid + 1); |
961d4119 | 1064 | for (i = old_max_uid; i >= 0; i--) regmove_bb_head[i] = -1; |
e0082a72 | 1065 | FOR_EACH_BB (bb) |
a813c111 | 1066 | regmove_bb_head[INSN_UID (BB_HEAD (bb))] = bb->index; |
ddc8bed2 | 1067 | |
8c660648 JL |
1068 | /* A forward/backward pass. Replace output operands with input operands. */ |
1069 | ||
184bb750 | 1070 | for (pass = 0; pass <= 2; pass++) |
8c660648 | 1071 | { |
184bb750 | 1072 | if (! flag_regmove && pass >= flag_expensive_optimizations) |
4da896b2 | 1073 | goto done; |
184bb750 | 1074 | |
10d22567 ZD |
1075 | if (dump_file) |
1076 | fprintf (dump_file, "Starting %s pass...\n", | |
8c660648 JL |
1077 | pass ? "backward" : "forward"); |
1078 | ||
1079 | for (insn = pass ? get_last_insn () : f; insn; | |
1080 | insn = pass ? PREV_INSN (insn) : NEXT_INSN (insn)) | |
1081 | { | |
184bb750 | 1082 | rtx set; |
0eadeb15 | 1083 | int op_no, match_no; |
184bb750 | 1084 | |
184bb750 R |
1085 | set = single_set (insn); |
1086 | if (! set) | |
1087 | continue; | |
8c660648 | 1088 | |
184bb750 R |
1089 | if (flag_expensive_optimizations && ! pass |
1090 | && (GET_CODE (SET_SRC (set)) == SIGN_EXTEND | |
1091 | || GET_CODE (SET_SRC (set)) == ZERO_EXTEND) | |
f8cfc6aa JQ |
1092 | && REG_P (XEXP (SET_SRC (set), 0)) |
1093 | && REG_P (SET_DEST (set))) | |
184bb750 R |
1094 | optimize_reg_copy_3 (insn, SET_DEST (set), SET_SRC (set)); |
1095 | ||
1096 | if (flag_expensive_optimizations && ! pass | |
f8cfc6aa JQ |
1097 | && REG_P (SET_SRC (set)) |
1098 | && REG_P (SET_DEST (set))) | |
184bb750 R |
1099 | { |
1100 | /* If this is a register-register copy where SRC is not dead, | |
1101 | see if we can optimize it. If this optimization succeeds, | |
1102 | it will become a copy where SRC is dead. */ | |
1103 | if ((find_reg_note (insn, REG_DEAD, SET_SRC (set)) | |
1104 | || optimize_reg_copy_1 (insn, SET_DEST (set), SET_SRC (set))) | |
1105 | && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER) | |
8c660648 | 1106 | { |
184bb750 R |
1107 | /* Similarly for a pseudo-pseudo copy when SRC is dead. */ |
1108 | if (REGNO (SET_SRC (set)) >= FIRST_PSEUDO_REGISTER) | |
1109 | optimize_reg_copy_2 (insn, SET_DEST (set), SET_SRC (set)); | |
1110 | if (regno_src_regno[REGNO (SET_DEST (set))] < 0 | |
1111 | && SET_SRC (set) != SET_DEST (set)) | |
8c660648 | 1112 | { |
8e2e89f7 | 1113 | int srcregno = REGNO (SET_SRC (set)); |
184bb750 R |
1114 | if (regno_src_regno[srcregno] >= 0) |
1115 | srcregno = regno_src_regno[srcregno]; | |
1116 | regno_src_regno[REGNO (SET_DEST (set))] = srcregno; | |
8c660648 JL |
1117 | } |
1118 | } | |
184bb750 | 1119 | } |
a6a2274a KH |
1120 | if (! flag_regmove) |
1121 | continue; | |
184bb750 | 1122 | |
3363316f | 1123 | if (! find_matches (insn, &match)) |
184bb750 R |
1124 | continue; |
1125 | ||
1126 | /* Now scan through the operands looking for a source operand | |
1127 | which is supposed to match the destination operand. | |
1128 | Then scan forward for an instruction which uses the dest | |
1129 | operand. | |
1130 | If it dies there, then replace the dest in both operands with | |
1131 | the source operand. */ | |
1132 | ||
1ccbefce | 1133 | for (op_no = 0; op_no < recog_data.n_operands; op_no++) |
184bb750 | 1134 | { |
5e9defae | 1135 | rtx src, dst, src_subreg; |
184bb750 R |
1136 | enum reg_class src_class, dst_class; |
1137 | ||
0eadeb15 | 1138 | match_no = match.with[op_no]; |
184bb750 R |
1139 | |
1140 | /* Nothing to do if the two operands aren't supposed to match. */ | |
0eadeb15 | 1141 | if (match_no < 0) |
184bb750 R |
1142 | continue; |
1143 | ||
1ccbefce RH |
1144 | src = recog_data.operand[op_no]; |
1145 | dst = recog_data.operand[match_no]; | |
184bb750 | 1146 | |
f8cfc6aa | 1147 | if (!REG_P (src)) |
184bb750 R |
1148 | continue; |
1149 | ||
1150 | src_subreg = src; | |
1151 | if (GET_CODE (dst) == SUBREG | |
1152 | && GET_MODE_SIZE (GET_MODE (dst)) | |
1153 | >= GET_MODE_SIZE (GET_MODE (SUBREG_REG (dst)))) | |
1154 | { | |
184bb750 | 1155 | dst = SUBREG_REG (dst); |
d281a1f1 UW |
1156 | src_subreg = lowpart_subreg (GET_MODE (dst), |
1157 | src, GET_MODE (src)); | |
1158 | if (!src_subreg) | |
1159 | continue; | |
184bb750 | 1160 | } |
f8cfc6aa | 1161 | if (!REG_P (dst) |
184bb750 R |
1162 | || REGNO (dst) < FIRST_PSEUDO_REGISTER) |
1163 | continue; | |
1164 | ||
1165 | if (REGNO (src) < FIRST_PSEUDO_REGISTER) | |
1166 | { | |
0eadeb15 | 1167 | if (match.commutative[op_no] < op_no) |
184bb750 R |
1168 | regno_src_regno[REGNO (dst)] = REGNO (src); |
1169 | continue; | |
1170 | } | |
1171 | ||
1172 | if (REG_LIVE_LENGTH (REGNO (src)) < 0) | |
1173 | continue; | |
1174 | ||
0eadeb15 | 1175 | /* op_no/src must be a read-only operand, and |
184bb750 | 1176 | match_operand/dst must be a write-only operand. */ |
0eadeb15 BS |
1177 | if (match.use[op_no] != READ |
1178 | || match.use[match_no] != WRITE) | |
184bb750 R |
1179 | continue; |
1180 | ||
0eadeb15 | 1181 | if (match.early_clobber[match_no] |
4b983fdc | 1182 | && count_occurrences (PATTERN (insn), src, 0) > 1) |
184bb750 R |
1183 | continue; |
1184 | ||
1185 | /* Make sure match_operand is the destination. */ | |
1ccbefce | 1186 | if (recog_data.operand[match_no] != SET_DEST (set)) |
184bb750 R |
1187 | continue; |
1188 | ||
dc297297 | 1189 | /* If the operands already match, then there is nothing to do. */ |
1ccbefce | 1190 | if (operands_match_p (src, dst)) |
184bb750 R |
1191 | continue; |
1192 | ||
1ccbefce RH |
1193 | /* But in the commutative case, we might find a better match. */ |
1194 | if (match.commutative[op_no] >= 0) | |
1195 | { | |
1196 | rtx comm = recog_data.operand[match.commutative[op_no]]; | |
1197 | if (operands_match_p (comm, dst) | |
1198 | && (replacement_quality (comm) | |
1199 | >= replacement_quality (src))) | |
1200 | continue; | |
1201 | } | |
1202 | ||
184bb750 R |
1203 | src_class = reg_preferred_class (REGNO (src)); |
1204 | dst_class = reg_preferred_class (REGNO (dst)); | |
3bb806ed | 1205 | if (! regclass_compatible_p (src_class, dst_class)) |
184bb750 | 1206 | continue; |
174fa2c4 | 1207 | |
f3029065 KH |
1208 | if (GET_MODE (src) != GET_MODE (dst)) |
1209 | continue; | |
1210 | ||
184bb750 | 1211 | if (fixup_match_1 (insn, set, src, src_subreg, dst, pass, |
10d22567 | 1212 | op_no, match_no)) |
184bb750 | 1213 | break; |
8c660648 JL |
1214 | } |
1215 | } | |
1216 | } | |
1217 | ||
1218 | /* A backward pass. Replace input operands with output operands. */ | |
1219 | ||
10d22567 ZD |
1220 | if (dump_file) |
1221 | fprintf (dump_file, "Starting backward pass...\n"); | |
8c660648 JL |
1222 | |
1223 | for (insn = get_last_insn (); insn; insn = PREV_INSN (insn)) | |
1224 | { | |
2c3c49de | 1225 | if (INSN_P (insn)) |
8c660648 | 1226 | { |
0eadeb15 | 1227 | int op_no, match_no; |
ddc8bed2 | 1228 | int success = 0; |
0eadeb15 | 1229 | |
3363316f | 1230 | if (! find_matches (insn, &match)) |
8c660648 JL |
1231 | continue; |
1232 | ||
8c660648 JL |
1233 | /* Now scan through the operands looking for a destination operand |
1234 | which is supposed to match a source operand. | |
1235 | Then scan backward for an instruction which sets the source | |
1236 | operand. If safe, then replace the source operand with the | |
1237 | dest operand in both instructions. */ | |
1238 | ||
ddc8bed2 MM |
1239 | copy_src = NULL_RTX; |
1240 | copy_dst = NULL_RTX; | |
1ccbefce | 1241 | for (op_no = 0; op_no < recog_data.n_operands; op_no++) |
8c660648 | 1242 | { |
184bb750 R |
1243 | rtx set, p, src, dst; |
1244 | rtx src_note, dst_note; | |
184bb750 R |
1245 | int num_calls = 0; |
1246 | enum reg_class src_class, dst_class; | |
1247 | int length; | |
8c660648 | 1248 | |
0eadeb15 | 1249 | match_no = match.with[op_no]; |
8c660648 | 1250 | |
184bb750 | 1251 | /* Nothing to do if the two operands aren't supposed to match. */ |
0eadeb15 | 1252 | if (match_no < 0) |
184bb750 | 1253 | continue; |
8c660648 | 1254 | |
1ccbefce RH |
1255 | dst = recog_data.operand[match_no]; |
1256 | src = recog_data.operand[op_no]; | |
8c660648 | 1257 | |
f8cfc6aa | 1258 | if (!REG_P (src)) |
184bb750 | 1259 | continue; |
8c660648 | 1260 | |
f8cfc6aa | 1261 | if (!REG_P (dst) |
184bb750 | 1262 | || REGNO (dst) < FIRST_PSEUDO_REGISTER |
3721581a | 1263 | || REG_LIVE_LENGTH (REGNO (dst)) < 0 |
41b3243e | 1264 | || GET_MODE (src) != GET_MODE (dst)) |
184bb750 | 1265 | continue; |
8c660648 | 1266 | |
dc297297 | 1267 | /* If the operands already match, then there is nothing to do. */ |
1ccbefce | 1268 | if (operands_match_p (src, dst)) |
184bb750 | 1269 | continue; |
8c660648 | 1270 | |
1ccbefce RH |
1271 | if (match.commutative[op_no] >= 0) |
1272 | { | |
1273 | rtx comm = recog_data.operand[match.commutative[op_no]]; | |
1274 | if (operands_match_p (comm, dst)) | |
1275 | continue; | |
1276 | } | |
1277 | ||
184bb750 R |
1278 | set = single_set (insn); |
1279 | if (! set) | |
1280 | continue; | |
8c660648 | 1281 | |
bb948ad3 RZ |
1282 | /* Note that single_set ignores parts of a parallel set for |
1283 | which one of the destinations is REG_UNUSED. We can't | |
1284 | handle that here, since we can wind up rewriting things | |
1285 | such that a single register is set twice within a single | |
1286 | parallel. */ | |
1287 | if (reg_set_p (src, insn)) | |
1288 | continue; | |
1289 | ||
0eadeb15 | 1290 | /* match_no/dst must be a write-only operand, and |
184bb750 | 1291 | operand_operand/src must be a read-only operand. */ |
0eadeb15 BS |
1292 | if (match.use[op_no] != READ |
1293 | || match.use[match_no] != WRITE) | |
184bb750 | 1294 | continue; |
8c660648 | 1295 | |
0eadeb15 | 1296 | if (match.early_clobber[match_no] |
4b983fdc | 1297 | && count_occurrences (PATTERN (insn), src, 0) > 1) |
184bb750 | 1298 | continue; |
8c660648 | 1299 | |
0eadeb15 | 1300 | /* Make sure match_no is the destination. */ |
1ccbefce | 1301 | if (recog_data.operand[match_no] != SET_DEST (set)) |
184bb750 | 1302 | continue; |
8c660648 | 1303 | |
184bb750 R |
1304 | if (REGNO (src) < FIRST_PSEUDO_REGISTER) |
1305 | { | |
1306 | if (GET_CODE (SET_SRC (set)) == PLUS | |
1307 | && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT | |
1308 | && XEXP (SET_SRC (set), 0) == src | |
1309 | && fixup_match_2 (insn, dst, src, | |
10d22567 | 1310 | XEXP (SET_SRC (set), 1))) |
184bb750 R |
1311 | break; |
1312 | continue; | |
1313 | } | |
1314 | src_class = reg_preferred_class (REGNO (src)); | |
1315 | dst_class = reg_preferred_class (REGNO (dst)); | |
fd973d56 JH |
1316 | |
1317 | if (! (src_note = find_reg_note (insn, REG_DEAD, src))) | |
ddc8bed2 | 1318 | { |
fd973d56 JH |
1319 | /* We used to force the copy here like in other cases, but |
1320 | it produces worse code, as it eliminates no copy | |
1321 | instructions and the copy emitted will be produced by | |
1322 | reload anyway. On patterns with multiple alternatives, | |
14b493d6 | 1323 | there may be better solution available. |
fd973d56 JH |
1324 | |
1325 | In particular this change produced slower code for numeric | |
1326 | i387 programs. */ | |
1327 | ||
ddc8bed2 MM |
1328 | continue; |
1329 | } | |
8c660648 | 1330 | |
fd973d56 | 1331 | if (! regclass_compatible_p (src_class, dst_class)) |
ddc8bed2 MM |
1332 | { |
1333 | if (!copy_src) | |
1334 | { | |
1335 | copy_src = src; | |
1336 | copy_dst = dst; | |
1337 | } | |
1338 | continue; | |
1339 | } | |
1340 | ||
fd973d56 JH |
1341 | /* Can not modify an earlier insn to set dst if this insn |
1342 | uses an old value in the source. */ | |
1343 | if (reg_overlap_mentioned_p (dst, SET_SRC (set))) | |
ddc8bed2 MM |
1344 | { |
1345 | if (!copy_src) | |
1346 | { | |
1347 | copy_src = src; | |
1348 | copy_dst = dst; | |
1349 | } | |
1350 | continue; | |
1351 | } | |
8c660648 | 1352 | |
184bb750 R |
1353 | /* If src is set once in a different basic block, |
1354 | and is set equal to a constant, then do not use | |
1355 | it for this optimization, as this would make it | |
1356 | no longer equivalent to a constant. */ | |
ddc8bed2 | 1357 | |
a6a2274a | 1358 | if (reg_is_remote_constant_p (src, insn, f)) |
ddc8bed2 MM |
1359 | { |
1360 | if (!copy_src) | |
1361 | { | |
1362 | copy_src = src; | |
1363 | copy_dst = dst; | |
1364 | } | |
1365 | continue; | |
1366 | } | |
1367 | ||
1368 | ||
10d22567 ZD |
1369 | if (dump_file) |
1370 | fprintf (dump_file, | |
ddc8bed2 | 1371 | "Could fix operand %d of insn %d matching operand %d.\n", |
0eadeb15 | 1372 | op_no, INSN_UID (insn), match_no); |
8c660648 | 1373 | |
184bb750 R |
1374 | /* Scan backward to find the first instruction that uses |
1375 | the input operand. If the operand is set here, then | |
0eadeb15 | 1376 | replace it in both instructions with match_no. */ |
184bb750 R |
1377 | |
1378 | for (length = 0, p = PREV_INSN (insn); p; p = PREV_INSN (p)) | |
1379 | { | |
1380 | rtx pset; | |
1381 | ||
7bf825d2 JW |
1382 | /* ??? We can't scan past the end of a basic block without |
1383 | updating the register lifetime info | |
a1c1fdd0 RK |
1384 | (REG_DEAD/basic_block_live_at_start). */ |
1385 | if (perhaps_ends_bb_p (p)) | |
7bf825d2 | 1386 | break; |
a1c1fdd0 | 1387 | else if (! INSN_P (p)) |
184bb750 | 1388 | continue; |
8c660648 | 1389 | |
184bb750 | 1390 | length++; |
8c660648 | 1391 | |
184bb750 R |
1392 | /* ??? See if all of SRC is set in P. This test is much |
1393 | more conservative than it needs to be. */ | |
1394 | pset = single_set (p); | |
1395 | if (pset && SET_DEST (pset) == src) | |
1396 | { | |
1397 | /* We use validate_replace_rtx, in case there | |
1398 | are multiple identical source operands. All of | |
1399 | them have to be changed at the same time. */ | |
1400 | if (validate_replace_rtx (src, dst, insn)) | |
8c660648 | 1401 | { |
184bb750 R |
1402 | if (validate_change (p, &SET_DEST (pset), |
1403 | dst, 0)) | |
1404 | success = 1; | |
1405 | else | |
8c660648 | 1406 | { |
184bb750 R |
1407 | /* Change all source operands back. |
1408 | This modifies the dst as a side-effect. */ | |
1409 | validate_replace_rtx (dst, src, insn); | |
1410 | /* Now make sure the dst is right. */ | |
1411 | validate_change (insn, | |
1ccbefce | 1412 | recog_data.operand_loc[match_no], |
184bb750 | 1413 | dst, 0); |
8c660648 | 1414 | } |
8c660648 | 1415 | } |
184bb750 R |
1416 | break; |
1417 | } | |
1418 | ||
1419 | if (reg_overlap_mentioned_p (src, PATTERN (p)) | |
1420 | || reg_overlap_mentioned_p (dst, PATTERN (p))) | |
1421 | break; | |
8c660648 | 1422 | |
184bb750 R |
1423 | /* If we have passed a call instruction, and the |
1424 | pseudo-reg DST is not already live across a call, | |
1425 | then don't perform the optimization. */ | |
4b4bf941 | 1426 | if (CALL_P (p)) |
184bb750 R |
1427 | { |
1428 | num_calls++; | |
1429 | ||
1430 | if (REG_N_CALLS_CROSSED (REGNO (dst)) == 0) | |
8c660648 | 1431 | break; |
184bb750 R |
1432 | } |
1433 | } | |
8c660648 | 1434 | |
184bb750 R |
1435 | if (success) |
1436 | { | |
1437 | int dstno, srcno; | |
8c660648 | 1438 | |
184bb750 R |
1439 | /* Remove the death note for SRC from INSN. */ |
1440 | remove_note (insn, src_note); | |
1441 | /* Move the death note for SRC to P if it is used | |
1442 | there. */ | |
1443 | if (reg_overlap_mentioned_p (src, PATTERN (p))) | |
1444 | { | |
1445 | XEXP (src_note, 1) = REG_NOTES (p); | |
1446 | REG_NOTES (p) = src_note; | |
8c660648 | 1447 | } |
184bb750 R |
1448 | /* If there is a REG_DEAD note for DST on P, then remove |
1449 | it, because DST is now set there. */ | |
5e9defae | 1450 | if ((dst_note = find_reg_note (p, REG_DEAD, dst))) |
184bb750 R |
1451 | remove_note (p, dst_note); |
1452 | ||
1453 | dstno = REGNO (dst); | |
1454 | srcno = REGNO (src); | |
1455 | ||
1456 | REG_N_SETS (dstno)++; | |
1457 | REG_N_SETS (srcno)--; | |
8c660648 | 1458 | |
184bb750 R |
1459 | REG_N_CALLS_CROSSED (dstno) += num_calls; |
1460 | REG_N_CALLS_CROSSED (srcno) -= num_calls; | |
1461 | ||
1462 | REG_LIVE_LENGTH (dstno) += length; | |
1463 | if (REG_LIVE_LENGTH (srcno) >= 0) | |
8c660648 | 1464 | { |
184bb750 R |
1465 | REG_LIVE_LENGTH (srcno) -= length; |
1466 | /* REG_LIVE_LENGTH is only an approximation after | |
1467 | combine if sched is not run, so make sure that we | |
1468 | still have a reasonable value. */ | |
1469 | if (REG_LIVE_LENGTH (srcno) < 2) | |
1470 | REG_LIVE_LENGTH (srcno) = 2; | |
1471 | } | |
8c660648 | 1472 | |
10d22567 ZD |
1473 | if (dump_file) |
1474 | fprintf (dump_file, | |
184bb750 | 1475 | "Fixed operand %d of insn %d matching operand %d.\n", |
0eadeb15 | 1476 | op_no, INSN_UID (insn), match_no); |
8c660648 | 1477 | |
184bb750 | 1478 | break; |
8c660648 JL |
1479 | } |
1480 | } | |
ddc8bed2 MM |
1481 | |
1482 | /* If we weren't able to replace any of the alternatives, try an | |
14b493d6 | 1483 | alternative approach of copying the source to the destination. */ |
ddc8bed2 | 1484 | if (!success && copy_src != NULL_RTX) |
1b7c4a37 | 1485 | copy_src_to_dest (insn, copy_src, copy_dst, old_max_uid); |
ddc8bed2 | 1486 | |
8c660648 JL |
1487 | } |
1488 | } | |
961d4119 BS |
1489 | |
1490 | /* In fixup_match_1, some insns may have been inserted after basic block | |
1491 | ends. Fix that here. */ | |
e0082a72 | 1492 | FOR_EACH_BB (bb) |
961d4119 | 1493 | { |
a813c111 | 1494 | rtx end = BB_END (bb); |
961d4119 BS |
1495 | rtx new = end; |
1496 | rtx next = NEXT_INSN (new); | |
1497 | while (next != 0 && INSN_UID (next) >= old_max_uid | |
a813c111 | 1498 | && (bb->next_bb == EXIT_BLOCK_PTR || BB_HEAD (bb->next_bb) != next)) |
961d4119 | 1499 | new = next, next = NEXT_INSN (new); |
a813c111 | 1500 | BB_END (bb) = new; |
961d4119 | 1501 | } |
4da896b2 MM |
1502 | |
1503 | done: | |
1504 | /* Clean up. */ | |
1505 | free (regno_src_regno); | |
1506 | free (regmove_bb_head); | |
8c660648 JL |
1507 | } |
1508 | ||
0eadeb15 BS |
1509 | /* Returns nonzero if INSN's pattern has matching constraints for any operand. |
1510 | Returns 0 if INSN can't be recognized, or if the alternative can't be | |
1511 | determined. | |
b1a7d591 JW |
1512 | |
1513 | Initialize the info in MATCHP based on the constraints. */ | |
184bb750 R |
1514 | |
1515 | static int | |
0c20a65f | 1516 | find_matches (rtx insn, struct match *matchp) |
184bb750 R |
1517 | { |
1518 | int likely_spilled[MAX_RECOG_OPERANDS]; | |
0eadeb15 | 1519 | int op_no; |
184bb750 R |
1520 | int any_matches = 0; |
1521 | ||
0eadeb15 BS |
1522 | extract_insn (insn); |
1523 | if (! constrain_operands (0)) | |
1524 | return 0; | |
184bb750 R |
1525 | |
1526 | /* Must initialize this before main loop, because the code for | |
1527 | the commutative case may set matches for operands other than | |
1528 | the current one. */ | |
1ccbefce | 1529 | for (op_no = recog_data.n_operands; --op_no >= 0; ) |
0eadeb15 | 1530 | matchp->with[op_no] = matchp->commutative[op_no] = -1; |
184bb750 | 1531 | |
1ccbefce | 1532 | for (op_no = 0; op_no < recog_data.n_operands; op_no++) |
184bb750 | 1533 | { |
9b3142b3 KG |
1534 | const char *p; |
1535 | char c; | |
184bb750 R |
1536 | int i = 0; |
1537 | ||
1ccbefce | 1538 | p = recog_data.constraints[op_no]; |
184bb750 | 1539 | |
0eadeb15 BS |
1540 | likely_spilled[op_no] = 0; |
1541 | matchp->use[op_no] = READ; | |
1542 | matchp->early_clobber[op_no] = 0; | |
184bb750 | 1543 | if (*p == '=') |
0eadeb15 | 1544 | matchp->use[op_no] = WRITE; |
184bb750 | 1545 | else if (*p == '+') |
0eadeb15 | 1546 | matchp->use[op_no] = READWRITE; |
184bb750 R |
1547 | |
1548 | for (;*p && i < which_alternative; p++) | |
1549 | if (*p == ',') | |
1550 | i++; | |
1551 | ||
97488870 R |
1552 | while ((c = *p) != '\0' && c != ',') |
1553 | { | |
1554 | switch (c) | |
84b72302 | 1555 | { |
97488870 R |
1556 | case '=': |
1557 | break; | |
1558 | case '+': | |
1559 | break; | |
1560 | case '&': | |
1561 | matchp->early_clobber[op_no] = 1; | |
1562 | break; | |
1563 | case '%': | |
1564 | matchp->commutative[op_no] = op_no + 1; | |
1565 | matchp->commutative[op_no + 1] = op_no; | |
1566 | break; | |
1567 | ||
1568 | case '0': case '1': case '2': case '3': case '4': | |
1569 | case '5': case '6': case '7': case '8': case '9': | |
1570 | { | |
1571 | char *end; | |
1572 | unsigned long match_ul = strtoul (p, &end, 10); | |
1573 | int match = match_ul; | |
2cc2d4bb | 1574 | |
97488870 | 1575 | p = end; |
84b72302 | 1576 | |
97488870 R |
1577 | if (match < op_no && likely_spilled[match]) |
1578 | continue; | |
1579 | matchp->with[op_no] = match; | |
1580 | any_matches = 1; | |
1581 | if (matchp->commutative[op_no] >= 0) | |
1582 | matchp->with[matchp->commutative[op_no]] = match; | |
1583 | } | |
1584 | continue; | |
84b72302 | 1585 | |
184bb750 R |
1586 | case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'h': |
1587 | case 'j': case 'k': case 'l': case 'p': case 'q': case 't': case 'u': | |
1588 | case 'v': case 'w': case 'x': case 'y': case 'z': case 'A': case 'B': | |
1589 | case 'C': case 'D': case 'W': case 'Y': case 'Z': | |
97488870 | 1590 | if (CLASS_LIKELY_SPILLED_P (REG_CLASS_FROM_CONSTRAINT ((unsigned char) c, p) )) |
0eadeb15 | 1591 | likely_spilled[op_no] = 1; |
184bb750 R |
1592 | break; |
1593 | } | |
97488870 R |
1594 | p += CONSTRAINT_LEN (c, p); |
1595 | } | |
184bb750 | 1596 | } |
0eadeb15 | 1597 | return any_matches; |
184bb750 R |
1598 | } |
1599 | ||
ec7c0481 AO |
1600 | /* Try to replace all occurrences of DST_REG with SRC in LOC, that is |
1601 | assumed to be in INSN. */ | |
1602 | ||
1603 | static void | |
0c20a65f | 1604 | replace_in_call_usage (rtx *loc, unsigned int dst_reg, rtx src, rtx insn) |
ec7c0481 AO |
1605 | { |
1606 | rtx x = *loc; | |
1607 | enum rtx_code code; | |
1608 | const char *fmt; | |
1609 | int i, j; | |
1610 | ||
1611 | if (! x) | |
1612 | return; | |
174fa2c4 | 1613 | |
ec7c0481 AO |
1614 | code = GET_CODE (x); |
1615 | if (code == REG) | |
1616 | { | |
1617 | if (REGNO (x) != dst_reg) | |
1618 | return; | |
174fa2c4 | 1619 | |
ec7c0481 AO |
1620 | validate_change (insn, loc, src, 1); |
1621 | ||
1622 | return; | |
1623 | } | |
174fa2c4 | 1624 | |
ec7c0481 AO |
1625 | /* Process each of our operands recursively. */ |
1626 | fmt = GET_RTX_FORMAT (code); | |
1627 | for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++) | |
1628 | if (*fmt == 'e') | |
1629 | replace_in_call_usage (&XEXP (x, i), dst_reg, src, insn); | |
1630 | else if (*fmt == 'E') | |
1631 | for (j = 0; j < XVECLEN (x, i); j++) | |
1632 | replace_in_call_usage (& XVECEXP (x, i, j), dst_reg, src, insn); | |
1633 | } | |
1634 | ||
184bb750 | 1635 | /* Try to replace output operand DST in SET, with input operand SRC. SET is |
06671717 | 1636 | the only set in INSN. INSN has just been recognized and constrained. |
184bb750 R |
1637 | SRC is operand number OPERAND_NUMBER in INSN. |
1638 | DST is operand number MATCH_NUMBER in INSN. | |
1639 | If BACKWARD is nonzero, we have been called in a backward pass. | |
1640 | Return nonzero for success. */ | |
a1c1fdd0 | 1641 | |
184bb750 | 1642 | static int |
0c20a65f | 1643 | fixup_match_1 (rtx insn, rtx set, rtx src, rtx src_subreg, rtx dst, |
10d22567 | 1644 | int backward, int operand_number, int match_number) |
184bb750 R |
1645 | { |
1646 | rtx p; | |
1647 | rtx post_inc = 0, post_inc_set = 0, search_end = 0; | |
1648 | int success = 0; | |
1649 | int num_calls = 0, s_num_calls = 0; | |
1650 | enum rtx_code code = NOTE; | |
0334ef47 | 1651 | HOST_WIDE_INT insn_const = 0, newconst = 0; |
184bb750 | 1652 | rtx overlap = 0; /* need to move insn ? */ |
a544cfd2 | 1653 | rtx src_note = find_reg_note (insn, REG_DEAD, src), dst_note = NULL_RTX; |
1b7c4a37 | 1654 | int length, s_length; |
184bb750 R |
1655 | |
1656 | if (! src_note) | |
1657 | { | |
1658 | /* Look for (set (regX) (op regA constX)) | |
1659 | (set (regY) (op regA constY)) | |
1660 | and change that to | |
1661 | (set (regA) (op regA constX)). | |
1662 | (set (regY) (op regA constY-constX)). | |
1663 | This works for add and shift operations, if | |
1664 | regA is dead after or set by the second insn. */ | |
1665 | ||
1666 | code = GET_CODE (SET_SRC (set)); | |
1667 | if ((code == PLUS || code == LSHIFTRT | |
1668 | || code == ASHIFT || code == ASHIFTRT) | |
1669 | && XEXP (SET_SRC (set), 0) == src | |
1670 | && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT) | |
1671 | insn_const = INTVAL (XEXP (SET_SRC (set), 1)); | |
18bf656f | 1672 | else if (! stable_and_no_regs_but_for_p (SET_SRC (set), src, dst)) |
184bb750 R |
1673 | return 0; |
1674 | else | |
1675 | /* We might find a src_note while scanning. */ | |
1676 | code = NOTE; | |
1677 | } | |
1678 | ||
10d22567 ZD |
1679 | if (dump_file) |
1680 | fprintf (dump_file, | |
184bb750 R |
1681 | "Could fix operand %d of insn %d matching operand %d.\n", |
1682 | operand_number, INSN_UID (insn), match_number); | |
1683 | ||
1684 | /* If SRC is equivalent to a constant set in a different basic block, | |
1685 | then do not use it for this optimization. We want the equivalence | |
1686 | so that if we have to reload this register, we can reload the | |
1687 | constant, rather than extending the lifespan of the register. */ | |
1688 | if (reg_is_remote_constant_p (src, insn, get_insns ())) | |
1689 | return 0; | |
1690 | ||
1691 | /* Scan forward to find the next instruction that | |
1692 | uses the output operand. If the operand dies here, | |
1693 | then replace it in both instructions with | |
1694 | operand_number. */ | |
1695 | ||
1696 | for (length = s_length = 0, p = NEXT_INSN (insn); p; p = NEXT_INSN (p)) | |
1697 | { | |
4b4bf941 | 1698 | if (CALL_P (p)) |
ec7c0481 AO |
1699 | replace_in_call_usage (& CALL_INSN_FUNCTION_USAGE (p), |
1700 | REGNO (dst), src, p); | |
174fa2c4 | 1701 | |
7bf825d2 | 1702 | /* ??? We can't scan past the end of a basic block without updating |
a1c1fdd0 RK |
1703 | the register lifetime info (REG_DEAD/basic_block_live_at_start). */ |
1704 | if (perhaps_ends_bb_p (p)) | |
7bf825d2 | 1705 | break; |
a1c1fdd0 | 1706 | else if (! INSN_P (p)) |
184bb750 R |
1707 | continue; |
1708 | ||
1709 | length++; | |
1710 | if (src_note) | |
1711 | s_length++; | |
1712 | ||
1713 | if (reg_set_p (src, p) || reg_set_p (dst, p) | |
1714 | || (GET_CODE (PATTERN (p)) == USE | |
1715 | && reg_overlap_mentioned_p (src, XEXP (PATTERN (p), 0)))) | |
1716 | break; | |
1717 | ||
1718 | /* See if all of DST dies in P. This test is | |
1719 | slightly more conservative than it needs to be. */ | |
1720 | if ((dst_note = find_regno_note (p, REG_DEAD, REGNO (dst))) | |
1721 | && (GET_MODE (XEXP (dst_note, 0)) == GET_MODE (dst))) | |
1722 | { | |
2219e921 R |
1723 | /* If we would be moving INSN, check that we won't move it |
1724 | into the shadow of a live a live flags register. */ | |
1725 | /* ??? We only try to move it in front of P, although | |
1726 | we could move it anywhere between OVERLAP and P. */ | |
1727 | if (overlap && GET_MODE (PREV_INSN (p)) != VOIDmode) | |
1728 | break; | |
1729 | ||
184bb750 R |
1730 | if (! src_note) |
1731 | { | |
1732 | rtx q; | |
a544cfd2 | 1733 | rtx set2 = NULL_RTX; |
184bb750 R |
1734 | |
1735 | /* If an optimization is done, the value of SRC while P | |
1736 | is executed will be changed. Check that this is OK. */ | |
1737 | if (reg_overlap_mentioned_p (src, PATTERN (p))) | |
1738 | break; | |
1739 | for (q = p; q; q = NEXT_INSN (q)) | |
1740 | { | |
7bf825d2 JW |
1741 | /* ??? We can't scan past the end of a basic block without |
1742 | updating the register lifetime info | |
a1c1fdd0 RK |
1743 | (REG_DEAD/basic_block_live_at_start). */ |
1744 | if (perhaps_ends_bb_p (q)) | |
7bf825d2 JW |
1745 | { |
1746 | q = 0; | |
1747 | break; | |
1748 | } | |
a1c1fdd0 | 1749 | else if (! INSN_P (q)) |
184bb750 | 1750 | continue; |
a1c1fdd0 RK |
1751 | else if (reg_overlap_mentioned_p (src, PATTERN (q)) |
1752 | || reg_set_p (src, q)) | |
184bb750 R |
1753 | break; |
1754 | } | |
1755 | if (q) | |
1756 | set2 = single_set (q); | |
1757 | if (! q || ! set2 || GET_CODE (SET_SRC (set2)) != code | |
1758 | || XEXP (SET_SRC (set2), 0) != src | |
1759 | || GET_CODE (XEXP (SET_SRC (set2), 1)) != CONST_INT | |
1760 | || (SET_DEST (set2) != src | |
1761 | && ! find_reg_note (q, REG_DEAD, src))) | |
1762 | { | |
1763 | /* If this is a PLUS, we can still save a register by doing | |
1764 | src += insn_const; | |
1765 | P; | |
1766 | src -= insn_const; . | |
1767 | This also gives opportunities for subsequent | |
1768 | optimizations in the backward pass, so do it there. */ | |
1769 | if (code == PLUS && backward | |
3bb806ed R |
1770 | /* Don't do this if we can likely tie DST to SET_DEST |
1771 | of P later; we can't do this tying here if we got a | |
1772 | hard register. */ | |
1773 | && ! (dst_note && ! REG_N_CALLS_CROSSED (REGNO (dst)) | |
1774 | && single_set (p) | |
f8cfc6aa | 1775 | && REG_P (SET_DEST (single_set (p))) |
3bb806ed R |
1776 | && (REGNO (SET_DEST (single_set (p))) |
1777 | < FIRST_PSEUDO_REGISTER)) | |
dc2cb191 RH |
1778 | /* We may only emit an insn directly after P if we |
1779 | are not in the shadow of a live flags register. */ | |
1780 | && GET_MODE (p) == VOIDmode) | |
184bb750 R |
1781 | { |
1782 | search_end = q; | |
1783 | q = insn; | |
1784 | set2 = set; | |
1785 | newconst = -insn_const; | |
1786 | code = MINUS; | |
1787 | } | |
1788 | else | |
1789 | break; | |
1790 | } | |
1791 | else | |
1792 | { | |
1793 | newconst = INTVAL (XEXP (SET_SRC (set2), 1)) - insn_const; | |
1794 | /* Reject out of range shifts. */ | |
1795 | if (code != PLUS | |
1796 | && (newconst < 0 | |
a1c1fdd0 RK |
1797 | || ((unsigned HOST_WIDE_INT) newconst |
1798 | >= (GET_MODE_BITSIZE (GET_MODE | |
1799 | (SET_SRC (set2))))))) | |
184bb750 R |
1800 | break; |
1801 | if (code == PLUS) | |
1802 | { | |
1803 | post_inc = q; | |
1804 | if (SET_DEST (set2) != src) | |
1805 | post_inc_set = set2; | |
1806 | } | |
1807 | } | |
1808 | /* We use 1 as last argument to validate_change so that all | |
1809 | changes are accepted or rejected together by apply_change_group | |
1810 | when it is called by validate_replace_rtx . */ | |
1811 | validate_change (q, &XEXP (SET_SRC (set2), 1), | |
1812 | GEN_INT (newconst), 1); | |
1813 | } | |
1ccbefce | 1814 | validate_change (insn, recog_data.operand_loc[match_number], src, 1); |
184bb750 R |
1815 | if (validate_replace_rtx (dst, src_subreg, p)) |
1816 | success = 1; | |
1817 | break; | |
1818 | } | |
1819 | ||
1820 | if (reg_overlap_mentioned_p (dst, PATTERN (p))) | |
1821 | break; | |
1822 | if (! src_note && reg_overlap_mentioned_p (src, PATTERN (p))) | |
1823 | { | |
2219e921 R |
1824 | /* INSN was already checked to be movable wrt. the registers that it |
1825 | sets / uses when we found no REG_DEAD note for src on it, but it | |
1826 | still might clobber the flags register. We'll have to check that | |
1827 | we won't insert it into the shadow of a live flags register when | |
1828 | we finally know where we are to move it. */ | |
184bb750 R |
1829 | overlap = p; |
1830 | src_note = find_reg_note (p, REG_DEAD, src); | |
1831 | } | |
1832 | ||
1833 | /* If we have passed a call instruction, and the pseudo-reg SRC is not | |
1834 | already live across a call, then don't perform the optimization. */ | |
4b4bf941 | 1835 | if (CALL_P (p)) |
184bb750 R |
1836 | { |
1837 | if (REG_N_CALLS_CROSSED (REGNO (src)) == 0) | |
1838 | break; | |
1839 | ||
1840 | num_calls++; | |
1841 | ||
1842 | if (src_note) | |
1843 | s_num_calls++; | |
1844 | ||
1845 | } | |
1846 | } | |
1847 | ||
1848 | if (! success) | |
1849 | return 0; | |
1850 | ||
184bb750 R |
1851 | /* Remove the death note for DST from P. */ |
1852 | remove_note (p, dst_note); | |
1853 | if (code == MINUS) | |
1854 | { | |
1855 | post_inc = emit_insn_after (copy_rtx (PATTERN (insn)), p); | |
940da324 JL |
1856 | if ((HAVE_PRE_INCREMENT || HAVE_PRE_DECREMENT) |
1857 | && search_end | |
184bb750 R |
1858 | && try_auto_increment (search_end, post_inc, 0, src, newconst, 1)) |
1859 | post_inc = 0; | |
184bb750 R |
1860 | validate_change (insn, &XEXP (SET_SRC (set), 1), GEN_INT (insn_const), 0); |
1861 | REG_N_SETS (REGNO (src))++; | |
184bb750 R |
1862 | REG_LIVE_LENGTH (REGNO (src))++; |
1863 | } | |
1864 | if (overlap) | |
1865 | { | |
1866 | /* The lifetime of src and dest overlap, | |
1867 | but we can change this by moving insn. */ | |
1868 | rtx pat = PATTERN (insn); | |
1869 | if (src_note) | |
1870 | remove_note (overlap, src_note); | |
1ed9faee TM |
1871 | if ((HAVE_POST_INCREMENT || HAVE_POST_DECREMENT) |
1872 | && code == PLUS | |
184bb750 R |
1873 | && try_auto_increment (overlap, insn, 0, src, insn_const, 0)) |
1874 | insn = overlap; | |
1875 | else | |
184bb750 R |
1876 | { |
1877 | rtx notes = REG_NOTES (insn); | |
1878 | ||
1879 | emit_insn_after_with_line_notes (pat, PREV_INSN (p), insn); | |
ca6c03ca | 1880 | delete_insn (insn); |
184bb750 R |
1881 | /* emit_insn_after_with_line_notes has no |
1882 | return value, so search for the new insn. */ | |
ef178af3 | 1883 | insn = p; |
2c3c49de | 1884 | while (! INSN_P (insn) || PATTERN (insn) != pat) |
184bb750 R |
1885 | insn = PREV_INSN (insn); |
1886 | ||
1887 | REG_NOTES (insn) = notes; | |
1888 | } | |
1889 | } | |
1890 | /* Sometimes we'd generate src = const; src += n; | |
1891 | if so, replace the instruction that set src | |
1892 | in the first place. */ | |
1893 | ||
1894 | if (! overlap && (code == PLUS || code == MINUS)) | |
1895 | { | |
1896 | rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX); | |
a544cfd2 | 1897 | rtx q, set2 = NULL_RTX; |
184bb750 R |
1898 | int num_calls2 = 0, s_length2 = 0; |
1899 | ||
1900 | if (note && CONSTANT_P (XEXP (note, 0))) | |
1901 | { | |
8e2e89f7 | 1902 | for (q = PREV_INSN (insn); q; q = PREV_INSN (q)) |
184bb750 | 1903 | { |
7bf825d2 JW |
1904 | /* ??? We can't scan past the end of a basic block without |
1905 | updating the register lifetime info | |
a1c1fdd0 RK |
1906 | (REG_DEAD/basic_block_live_at_start). */ |
1907 | if (perhaps_ends_bb_p (q)) | |
7bf825d2 JW |
1908 | { |
1909 | q = 0; | |
1910 | break; | |
1911 | } | |
a1c1fdd0 | 1912 | else if (! INSN_P (q)) |
184bb750 | 1913 | continue; |
a1c1fdd0 | 1914 | |
184bb750 R |
1915 | s_length2++; |
1916 | if (reg_set_p (src, q)) | |
1917 | { | |
1918 | set2 = single_set (q); | |
1919 | break; | |
1920 | } | |
1921 | if (reg_overlap_mentioned_p (src, PATTERN (q))) | |
1922 | { | |
1923 | q = 0; | |
1924 | break; | |
1925 | } | |
4b4bf941 | 1926 | if (CALL_P (p)) |
184bb750 R |
1927 | num_calls2++; |
1928 | } | |
1929 | if (q && set2 && SET_DEST (set2) == src && CONSTANT_P (SET_SRC (set2)) | |
1930 | && validate_change (insn, &SET_SRC (set), XEXP (note, 0), 0)) | |
1931 | { | |
ca6c03ca | 1932 | delete_insn (q); |
184bb750 R |
1933 | REG_N_SETS (REGNO (src))--; |
1934 | REG_N_CALLS_CROSSED (REGNO (src)) -= num_calls2; | |
184bb750 R |
1935 | REG_LIVE_LENGTH (REGNO (src)) -= s_length2; |
1936 | insn_const = 0; | |
1937 | } | |
1938 | } | |
1939 | } | |
1a56b81f | 1940 | |
cb084004 | 1941 | if ((HAVE_PRE_INCREMENT || HAVE_PRE_DECREMENT) |
940da324 | 1942 | && (code == PLUS || code == MINUS) && insn_const |
184bb750 R |
1943 | && try_auto_increment (p, insn, 0, src, insn_const, 1)) |
1944 | insn = p; | |
940da324 JL |
1945 | else if ((HAVE_POST_INCREMENT || HAVE_POST_DECREMENT) |
1946 | && post_inc | |
184bb750 R |
1947 | && try_auto_increment (p, post_inc, post_inc_set, src, newconst, 0)) |
1948 | post_inc = 0; | |
184bb750 R |
1949 | /* If post_inc still prevails, try to find an |
1950 | insn where it can be used as a pre-in/decrement. | |
1951 | If code is MINUS, this was already tried. */ | |
1952 | if (post_inc && code == PLUS | |
1953 | /* Check that newconst is likely to be usable | |
1954 | in a pre-in/decrement before starting the search. */ | |
940da324 JL |
1955 | && ((HAVE_PRE_INCREMENT && newconst > 0 && newconst <= MOVE_MAX) |
1956 | || (HAVE_PRE_DECREMENT && newconst < 0 && newconst >= -MOVE_MAX)) | |
1957 | && exact_log2 (newconst)) | |
184bb750 R |
1958 | { |
1959 | rtx q, inc_dest; | |
1960 | ||
1961 | inc_dest = post_inc_set ? SET_DEST (post_inc_set) : src; | |
51723711 | 1962 | for (q = post_inc; (q = NEXT_INSN (q)); ) |
184bb750 | 1963 | { |
7bf825d2 | 1964 | /* ??? We can't scan past the end of a basic block without updating |
a1c1fdd0 | 1965 | the register lifetime info |
dc297297 | 1966 | (REG_DEAD/basic_block_live_at_start). */ |
a1c1fdd0 | 1967 | if (perhaps_ends_bb_p (q)) |
7bf825d2 | 1968 | break; |
a1c1fdd0 | 1969 | else if (! INSN_P (q)) |
184bb750 | 1970 | continue; |
a1c1fdd0 RK |
1971 | else if (src != inc_dest |
1972 | && (reg_overlap_mentioned_p (src, PATTERN (q)) | |
1973 | || reg_set_p (src, q))) | |
184bb750 | 1974 | break; |
a1c1fdd0 | 1975 | else if (reg_set_p (inc_dest, q)) |
184bb750 | 1976 | break; |
a1c1fdd0 | 1977 | else if (reg_overlap_mentioned_p (inc_dest, PATTERN (q))) |
184bb750 R |
1978 | { |
1979 | try_auto_increment (q, post_inc, | |
1980 | post_inc_set, inc_dest, newconst, 1); | |
1981 | break; | |
1982 | } | |
1983 | } | |
1984 | } | |
a1c1fdd0 | 1985 | |
184bb750 R |
1986 | /* Move the death note for DST to INSN if it is used |
1987 | there. */ | |
1988 | if (reg_overlap_mentioned_p (dst, PATTERN (insn))) | |
1989 | { | |
1990 | XEXP (dst_note, 1) = REG_NOTES (insn); | |
1991 | REG_NOTES (insn) = dst_note; | |
1992 | } | |
1993 | ||
1994 | if (src_note) | |
1995 | { | |
1996 | /* Move the death note for SRC from INSN to P. */ | |
1997 | if (! overlap) | |
1998 | remove_note (insn, src_note); | |
1999 | XEXP (src_note, 1) = REG_NOTES (p); | |
2000 | REG_NOTES (p) = src_note; | |
2001 | ||
2002 | REG_N_CALLS_CROSSED (REGNO (src)) += s_num_calls; | |
2003 | } | |
2004 | ||
2005 | REG_N_SETS (REGNO (src))++; | |
2006 | REG_N_SETS (REGNO (dst))--; | |
2007 | ||
2008 | REG_N_CALLS_CROSSED (REGNO (dst)) -= num_calls; | |
2009 | ||
2010 | REG_LIVE_LENGTH (REGNO (src)) += s_length; | |
2011 | if (REG_LIVE_LENGTH (REGNO (dst)) >= 0) | |
2012 | { | |
2013 | REG_LIVE_LENGTH (REGNO (dst)) -= length; | |
2014 | /* REG_LIVE_LENGTH is only an approximation after | |
2015 | combine if sched is not run, so make sure that we | |
2016 | still have a reasonable value. */ | |
2017 | if (REG_LIVE_LENGTH (REGNO (dst)) < 2) | |
2018 | REG_LIVE_LENGTH (REGNO (dst)) = 2; | |
2019 | } | |
10d22567 ZD |
2020 | if (dump_file) |
2021 | fprintf (dump_file, | |
184bb750 R |
2022 | "Fixed operand %d of insn %d matching operand %d.\n", |
2023 | operand_number, INSN_UID (insn), match_number); | |
2024 | return 1; | |
2025 | } | |
2026 | ||
2027 | ||
beb235f8 | 2028 | /* Return nonzero if X is stable and mentions no registers but for |
18bf656f R |
2029 | mentioning SRC or mentioning / changing DST . If in doubt, presume |
2030 | it is unstable. | |
2031 | The rationale is that we want to check if we can move an insn easily | |
389fdba0 | 2032 | while just paying attention to SRC and DST. */ |
8c660648 | 2033 | static int |
0c20a65f | 2034 | stable_and_no_regs_but_for_p (rtx x, rtx src, rtx dst) |
8c660648 JL |
2035 | { |
2036 | RTX_CODE code = GET_CODE (x); | |
2037 | switch (GET_RTX_CLASS (code)) | |
2038 | { | |
ec8e098d PB |
2039 | case RTX_UNARY: |
2040 | case RTX_BIN_ARITH: | |
2041 | case RTX_COMM_ARITH: | |
2042 | case RTX_COMPARE: | |
2043 | case RTX_COMM_COMPARE: | |
2044 | case RTX_TERNARY: | |
2045 | case RTX_BITFIELD_OPS: | |
8c660648 JL |
2046 | { |
2047 | int i; | |
6f7d635c | 2048 | const char *fmt = GET_RTX_FORMAT (code); |
8c660648 | 2049 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
18bf656f R |
2050 | if (fmt[i] == 'e' |
2051 | && ! stable_and_no_regs_but_for_p (XEXP (x, i), src, dst)) | |
8c660648 JL |
2052 | return 0; |
2053 | return 1; | |
2054 | } | |
ec8e098d | 2055 | case RTX_OBJ: |
18bf656f R |
2056 | if (code == REG) |
2057 | return x == src || x == dst; | |
2058 | /* If this is a MEM, look inside - there might be a register hidden in | |
2059 | the address of an unchanging MEM. */ | |
2060 | if (code == MEM | |
2061 | && ! stable_and_no_regs_but_for_p (XEXP (x, 0), src, dst)) | |
2062 | return 0; | |
938d968e | 2063 | /* Fall through. */ |
8c660648 JL |
2064 | default: |
2065 | return ! rtx_unstable_p (x); | |
2066 | } | |
2067 | } | |
1e7f0a48 | 2068 | \f |
174fa2c4 | 2069 | /* Track stack adjustments and stack memory references. Attempt to |
a1f300c0 | 2070 | reduce the number of stack adjustments by back-propagating across |
1e7f0a48 RH |
2071 | the memory references. |
2072 | ||
2073 | This is intended primarily for use with targets that do not define | |
2074 | ACCUMULATE_OUTGOING_ARGS. It is of significantly more value to | |
2075 | targets that define PREFERRED_STACK_BOUNDARY more aligned than | |
2076 | STACK_BOUNDARY (e.g. x86), or if not all registers can be pushed | |
2077 | (e.g. x86 fp regs) which would ordinarily have to be implemented | |
2078 | as a sub/mov pair due to restrictions in calls.c. | |
2079 | ||
a1f300c0 | 2080 | Propagation stops when any of the insns that need adjusting are |
1e7f0a48 RH |
2081 | (a) no longer valid because we've exceeded their range, (b) a |
2082 | non-trivial push instruction, or (c) a call instruction. | |
2083 | ||
2084 | Restriction B is based on the assumption that push instructions | |
2085 | are smaller or faster. If a port really wants to remove all | |
2086 | pushes, it should have defined ACCUMULATE_OUTGOING_ARGS. The | |
2087 | one exception that is made is for an add immediately followed | |
2088 | by a push. */ | |
2089 | ||
2090 | /* This structure records stack memory references between stack adjusting | |
2091 | instructions. */ | |
2092 | ||
2093 | struct csa_memlist | |
2094 | { | |
2095 | HOST_WIDE_INT sp_offset; | |
5a97f7c2 | 2096 | rtx insn, *mem; |
1e7f0a48 RH |
2097 | struct csa_memlist *next; |
2098 | }; | |
2099 | ||
0c20a65f AJ |
2100 | static int stack_memref_p (rtx); |
2101 | static rtx single_set_for_csa (rtx); | |
2102 | static void free_csa_memlist (struct csa_memlist *); | |
2103 | static struct csa_memlist *record_one_stack_memref (rtx, rtx *, | |
2104 | struct csa_memlist *); | |
2105 | static int try_apply_stack_adjustment (rtx, struct csa_memlist *, | |
2106 | HOST_WIDE_INT, HOST_WIDE_INT); | |
2107 | static void combine_stack_adjustments_for_block (basic_block); | |
2108 | static int record_stack_memrefs (rtx *, void *); | |
1e7f0a48 RH |
2109 | |
2110 | ||
2111 | /* Main entry point for stack adjustment combination. */ | |
2112 | ||
fe3c3571 | 2113 | static void |
0c20a65f | 2114 | combine_stack_adjustments (void) |
1e7f0a48 | 2115 | { |
e0082a72 | 2116 | basic_block bb; |
1e7f0a48 | 2117 | |
e0082a72 ZD |
2118 | FOR_EACH_BB (bb) |
2119 | combine_stack_adjustments_for_block (bb); | |
1e7f0a48 RH |
2120 | } |
2121 | ||
2122 | /* Recognize a MEM of the form (sp) or (plus sp const). */ | |
2123 | ||
2124 | static int | |
0c20a65f | 2125 | stack_memref_p (rtx x) |
1e7f0a48 | 2126 | { |
3c0cb5de | 2127 | if (!MEM_P (x)) |
9e11785b RH |
2128 | return 0; |
2129 | x = XEXP (x, 0); | |
2130 | ||
2131 | if (x == stack_pointer_rtx) | |
2132 | return 1; | |
2133 | if (GET_CODE (x) == PLUS | |
2134 | && XEXP (x, 0) == stack_pointer_rtx | |
2135 | && GET_CODE (XEXP (x, 1)) == CONST_INT) | |
2136 | return 1; | |
2137 | ||
2138 | return 0; | |
1e7f0a48 RH |
2139 | } |
2140 | ||
2141 | /* Recognize either normal single_set or the hack in i386.md for | |
2142 | tying fp and sp adjustments. */ | |
2143 | ||
2144 | static rtx | |
0c20a65f | 2145 | single_set_for_csa (rtx insn) |
1e7f0a48 RH |
2146 | { |
2147 | int i; | |
2148 | rtx tmp = single_set (insn); | |
2149 | if (tmp) | |
2150 | return tmp; | |
2151 | ||
4b4bf941 | 2152 | if (!NONJUMP_INSN_P (insn) |
1e7f0a48 RH |
2153 | || GET_CODE (PATTERN (insn)) != PARALLEL) |
2154 | return NULL_RTX; | |
2155 | ||
2156 | tmp = PATTERN (insn); | |
2157 | if (GET_CODE (XVECEXP (tmp, 0, 0)) != SET) | |
2158 | return NULL_RTX; | |
2159 | ||
2160 | for (i = 1; i < XVECLEN (tmp, 0); ++i) | |
2161 | { | |
2162 | rtx this = XVECEXP (tmp, 0, i); | |
2163 | ||
2164 | /* The special case is allowing a no-op set. */ | |
2165 | if (GET_CODE (this) == SET | |
2166 | && SET_SRC (this) == SET_DEST (this)) | |
2167 | ; | |
2168 | else if (GET_CODE (this) != CLOBBER | |
2169 | && GET_CODE (this) != USE) | |
2170 | return NULL_RTX; | |
2171 | } | |
2172 | ||
2173 | return XVECEXP (tmp, 0, 0); | |
2174 | } | |
2175 | ||
2176 | /* Free the list of csa_memlist nodes. */ | |
2177 | ||
2178 | static void | |
0c20a65f | 2179 | free_csa_memlist (struct csa_memlist *memlist) |
1e7f0a48 RH |
2180 | { |
2181 | struct csa_memlist *next; | |
2182 | for (; memlist ; memlist = next) | |
2183 | { | |
2184 | next = memlist->next; | |
2185 | free (memlist); | |
2186 | } | |
2187 | } | |
2188 | ||
2189 | /* Create a new csa_memlist node from the given memory reference. | |
2190 | It is already known that the memory is stack_memref_p. */ | |
2191 | ||
2192 | static struct csa_memlist * | |
0c20a65f | 2193 | record_one_stack_memref (rtx insn, rtx *mem, struct csa_memlist *next_memlist) |
1e7f0a48 RH |
2194 | { |
2195 | struct csa_memlist *ml; | |
2196 | ||
5ed6ace5 | 2197 | ml = XNEW (struct csa_memlist); |
1e7f0a48 | 2198 | |
5a97f7c2 | 2199 | if (XEXP (*mem, 0) == stack_pointer_rtx) |
1e7f0a48 RH |
2200 | ml->sp_offset = 0; |
2201 | else | |
5a97f7c2 | 2202 | ml->sp_offset = INTVAL (XEXP (XEXP (*mem, 0), 1)); |
1e7f0a48 RH |
2203 | |
2204 | ml->insn = insn; | |
2205 | ml->mem = mem; | |
2206 | ml->next = next_memlist; | |
2207 | ||
2208 | return ml; | |
2209 | } | |
2210 | ||
2211 | /* Attempt to apply ADJUST to the stack adjusting insn INSN, as well | |
2212 | as each of the memories in MEMLIST. Return true on success. */ | |
2213 | ||
2214 | static int | |
0c20a65f AJ |
2215 | try_apply_stack_adjustment (rtx insn, struct csa_memlist *memlist, HOST_WIDE_INT new_adjust, |
2216 | HOST_WIDE_INT delta) | |
1e7f0a48 RH |
2217 | { |
2218 | struct csa_memlist *ml; | |
2219 | rtx set; | |
2220 | ||
1e7f0a48 RH |
2221 | set = single_set_for_csa (insn); |
2222 | validate_change (insn, &XEXP (SET_SRC (set), 1), GEN_INT (new_adjust), 1); | |
2223 | ||
2224 | for (ml = memlist; ml ; ml = ml->next) | |
f1ec5147 RK |
2225 | validate_change |
2226 | (ml->insn, ml->mem, | |
2227 | replace_equiv_address_nv (*ml->mem, | |
2228 | plus_constant (stack_pointer_rtx, | |
2229 | ml->sp_offset - delta)), 1); | |
1e7f0a48 RH |
2230 | |
2231 | if (apply_change_group ()) | |
2232 | { | |
2233 | /* Succeeded. Update our knowledge of the memory references. */ | |
2234 | for (ml = memlist; ml ; ml = ml->next) | |
2235 | ml->sp_offset -= delta; | |
2236 | ||
2237 | return 1; | |
2238 | } | |
2239 | else | |
2240 | return 0; | |
2241 | } | |
2242 | ||
a2ee8430 JH |
2243 | /* Called via for_each_rtx and used to record all stack memory references in |
2244 | the insn and discard all other stack pointer references. */ | |
2245 | struct record_stack_memrefs_data | |
2246 | { | |
2247 | rtx insn; | |
2248 | struct csa_memlist *memlist; | |
2249 | }; | |
2250 | ||
2251 | static int | |
0c20a65f | 2252 | record_stack_memrefs (rtx *xp, void *data) |
a2ee8430 JH |
2253 | { |
2254 | rtx x = *xp; | |
2255 | struct record_stack_memrefs_data *d = | |
2256 | (struct record_stack_memrefs_data *) data; | |
2257 | if (!x) | |
2258 | return 0; | |
2259 | switch (GET_CODE (x)) | |
2260 | { | |
2261 | case MEM: | |
2262 | if (!reg_mentioned_p (stack_pointer_rtx, x)) | |
2263 | return -1; | |
2264 | /* We are not able to handle correctly all possible memrefs containing | |
f63d1bf7 | 2265 | stack pointer, so this check is necessary. */ |
a2ee8430 JH |
2266 | if (stack_memref_p (x)) |
2267 | { | |
2268 | d->memlist = record_one_stack_memref (d->insn, xp, d->memlist); | |
2269 | return -1; | |
2270 | } | |
2271 | return 1; | |
2272 | case REG: | |
d60e5448 | 2273 | /* ??? We want be able to handle non-memory stack pointer |
e0bb17a8 | 2274 | references later. For now just discard all insns referring to |
d60e5448 MM |
2275 | stack pointer outside mem expressions. We would probably |
2276 | want to teach validate_replace to simplify expressions first. | |
2277 | ||
2278 | We can't just compare with STACK_POINTER_RTX because the | |
2279 | reference to the stack pointer might be in some other mode. | |
14b493d6 | 2280 | In particular, an explicit clobber in an asm statement will |
e0bb17a8 | 2281 | result in a QImode clobber. */ |
d60e5448 | 2282 | if (REGNO (x) == STACK_POINTER_REGNUM) |
a2ee8430 JH |
2283 | return 1; |
2284 | break; | |
2285 | default: | |
2286 | break; | |
2287 | } | |
2288 | return 0; | |
2289 | } | |
2290 | ||
1e7f0a48 RH |
2291 | /* Subroutine of combine_stack_adjustments, called for each basic block. */ |
2292 | ||
174fa2c4 | 2293 | static void |
0c20a65f | 2294 | combine_stack_adjustments_for_block (basic_block bb) |
1e7f0a48 RH |
2295 | { |
2296 | HOST_WIDE_INT last_sp_adjust = 0; | |
2297 | rtx last_sp_set = NULL_RTX; | |
2298 | struct csa_memlist *memlist = NULL; | |
78414d74 | 2299 | rtx insn, next, set; |
a2ee8430 | 2300 | struct record_stack_memrefs_data data; |
78414d74 | 2301 | bool end_of_block = false; |
1e7f0a48 | 2302 | |
a813c111 | 2303 | for (insn = BB_HEAD (bb); !end_of_block ; insn = next) |
1e7f0a48 | 2304 | { |
a813c111 | 2305 | end_of_block = insn == BB_END (bb); |
1e7f0a48 RH |
2306 | next = NEXT_INSN (insn); |
2307 | ||
a2ee8430 | 2308 | if (! INSN_P (insn)) |
78414d74 | 2309 | continue; |
1e7f0a48 RH |
2310 | |
2311 | set = single_set_for_csa (insn); | |
2312 | if (set) | |
2313 | { | |
2314 | rtx dest = SET_DEST (set); | |
2315 | rtx src = SET_SRC (set); | |
2316 | ||
2317 | /* Find constant additions to the stack pointer. */ | |
2318 | if (dest == stack_pointer_rtx | |
2319 | && GET_CODE (src) == PLUS | |
2320 | && XEXP (src, 0) == stack_pointer_rtx | |
2321 | && GET_CODE (XEXP (src, 1)) == CONST_INT) | |
2322 | { | |
2323 | HOST_WIDE_INT this_adjust = INTVAL (XEXP (src, 1)); | |
2324 | ||
2325 | /* If we've not seen an adjustment previously, record | |
2326 | it now and continue. */ | |
2327 | if (! last_sp_set) | |
2328 | { | |
2329 | last_sp_set = insn; | |
2330 | last_sp_adjust = this_adjust; | |
78414d74 | 2331 | continue; |
1e7f0a48 RH |
2332 | } |
2333 | ||
2334 | /* If not all recorded memrefs can be adjusted, or the | |
2335 | adjustment is now too large for a constant addition, | |
595c2290 JH |
2336 | we cannot merge the two stack adjustments. |
2337 | ||
14b493d6 | 2338 | Also we need to be careful to not move stack pointer |
595c2290 JH |
2339 | such that we create stack accesses outside the allocated |
2340 | area. We can combine an allocation into the first insn, | |
2341 | or a deallocation into the second insn. We can not | |
2342 | combine an allocation followed by a deallocation. | |
2343 | ||
ff7cc307 | 2344 | The only somewhat frequent occurrence of the later is when |
595c2290 JH |
2345 | a function allocates a stack frame but does not use it. |
2346 | For this case, we would need to analyze rtl stream to be | |
2347 | sure that allocated area is really unused. This means not | |
2348 | only checking the memory references, but also all registers | |
2349 | or global memory references possibly containing a stack | |
2350 | frame address. | |
2351 | ||
2352 | Perhaps the best way to address this problem is to teach | |
2353 | gcc not to allocate stack for objects never used. */ | |
2354 | ||
2355 | /* Combine an allocation into the first instruction. */ | |
2356 | if (STACK_GROWS_DOWNWARD ? this_adjust <= 0 : this_adjust >= 0) | |
1e7f0a48 | 2357 | { |
595c2290 JH |
2358 | if (try_apply_stack_adjustment (last_sp_set, memlist, |
2359 | last_sp_adjust + this_adjust, | |
2360 | this_adjust)) | |
2361 | { | |
2362 | /* It worked! */ | |
78414d74 | 2363 | delete_insn (insn); |
595c2290 | 2364 | last_sp_adjust += this_adjust; |
78414d74 | 2365 | continue; |
595c2290 | 2366 | } |
1e7f0a48 RH |
2367 | } |
2368 | ||
595c2290 JH |
2369 | /* Otherwise we have a deallocation. Do not combine with |
2370 | a previous allocation. Combine into the second insn. */ | |
2371 | else if (STACK_GROWS_DOWNWARD | |
2372 | ? last_sp_adjust >= 0 : last_sp_adjust <= 0) | |
1e7f0a48 | 2373 | { |
595c2290 JH |
2374 | if (try_apply_stack_adjustment (insn, memlist, |
2375 | last_sp_adjust + this_adjust, | |
2376 | -last_sp_adjust)) | |
2377 | { | |
2378 | /* It worked! */ | |
53c17031 | 2379 | delete_insn (last_sp_set); |
595c2290 JH |
2380 | last_sp_set = insn; |
2381 | last_sp_adjust += this_adjust; | |
2382 | free_csa_memlist (memlist); | |
2383 | memlist = NULL; | |
78414d74 | 2384 | continue; |
595c2290 | 2385 | } |
1e7f0a48 RH |
2386 | } |
2387 | ||
78414d74 RS |
2388 | /* Combination failed. Restart processing from here. If |
2389 | deallocation+allocation conspired to cancel, we can | |
2390 | delete the old deallocation insn. */ | |
2391 | if (last_sp_set && last_sp_adjust == 0) | |
2392 | delete_insn (insn); | |
595c2290 JH |
2393 | free_csa_memlist (memlist); |
2394 | memlist = NULL; | |
2395 | last_sp_set = insn; | |
2396 | last_sp_adjust = this_adjust; | |
78414d74 | 2397 | continue; |
1e7f0a48 RH |
2398 | } |
2399 | ||
1e7f0a48 RH |
2400 | /* Find a predecrement of exactly the previous adjustment and |
2401 | turn it into a direct store. Obviously we can't do this if | |
2402 | there were any intervening uses of the stack pointer. */ | |
2403 | if (memlist == NULL | |
3c0cb5de | 2404 | && MEM_P (dest) |
756d6f0c JH |
2405 | && ((GET_CODE (XEXP (dest, 0)) == PRE_DEC |
2406 | && (last_sp_adjust | |
2407 | == (HOST_WIDE_INT) GET_MODE_SIZE (GET_MODE (dest)))) | |
2408 | || (GET_CODE (XEXP (dest, 0)) == PRE_MODIFY | |
2409 | && GET_CODE (XEXP (XEXP (dest, 0), 1)) == PLUS | |
2410 | && XEXP (XEXP (XEXP (dest, 0), 1), 0) == stack_pointer_rtx | |
2411 | && (GET_CODE (XEXP (XEXP (XEXP (dest, 0), 1), 1)) | |
2412 | == CONST_INT) | |
2413 | && (INTVAL (XEXP (XEXP (XEXP (dest, 0), 1), 1)) | |
2414 | == -last_sp_adjust))) | |
1e7f0a48 | 2415 | && XEXP (XEXP (dest, 0), 0) == stack_pointer_rtx |
9e11785b | 2416 | && ! reg_mentioned_p (stack_pointer_rtx, src) |
5d64361b | 2417 | && memory_address_p (GET_MODE (dest), stack_pointer_rtx) |
1e7f0a48 | 2418 | && validate_change (insn, &SET_DEST (set), |
792760b9 RK |
2419 | replace_equiv_address (dest, |
2420 | stack_pointer_rtx), | |
2421 | 0)) | |
1e7f0a48 | 2422 | { |
53c17031 | 2423 | delete_insn (last_sp_set); |
1e7f0a48 RH |
2424 | free_csa_memlist (memlist); |
2425 | memlist = NULL; | |
2426 | last_sp_set = NULL_RTX; | |
2427 | last_sp_adjust = 0; | |
78414d74 | 2428 | continue; |
1e7f0a48 RH |
2429 | } |
2430 | } | |
2431 | ||
a2ee8430 JH |
2432 | data.insn = insn; |
2433 | data.memlist = memlist; | |
4b4bf941 | 2434 | if (!CALL_P (insn) && last_sp_set |
a2ee8430 JH |
2435 | && !for_each_rtx (&PATTERN (insn), record_stack_memrefs, &data)) |
2436 | { | |
2437 | memlist = data.memlist; | |
78414d74 | 2438 | continue; |
a2ee8430 JH |
2439 | } |
2440 | memlist = data.memlist; | |
2441 | ||
174fa2c4 | 2442 | /* Otherwise, we were not able to process the instruction. |
1e7f0a48 RH |
2443 | Do not continue collecting data across such a one. */ |
2444 | if (last_sp_set | |
4b4bf941 | 2445 | && (CALL_P (insn) |
1e7f0a48 RH |
2446 | || reg_mentioned_p (stack_pointer_rtx, PATTERN (insn)))) |
2447 | { | |
78414d74 RS |
2448 | if (last_sp_set && last_sp_adjust == 0) |
2449 | delete_insn (last_sp_set); | |
1e7f0a48 RH |
2450 | free_csa_memlist (memlist); |
2451 | memlist = NULL; | |
2452 | last_sp_set = NULL_RTX; | |
2453 | last_sp_adjust = 0; | |
2454 | } | |
1e7f0a48 RH |
2455 | } |
2456 | ||
78414d74 RS |
2457 | if (last_sp_set && last_sp_adjust == 0) |
2458 | delete_insn (last_sp_set); | |
da0e2953 KH |
2459 | |
2460 | if (memlist) | |
2461 | free_csa_memlist (memlist); | |
1e7f0a48 | 2462 | } |
ef330312 PB |
2463 | \f |
2464 | static bool | |
2465 | gate_handle_regmove (void) | |
2466 | { | |
2467 | return (optimize > 0 && flag_regmove); | |
2468 | } | |
2469 | ||
2470 | ||
2471 | /* Register allocation pre-pass, to reduce number of moves necessary | |
2472 | for two-address machines. */ | |
c2924966 | 2473 | static unsigned int |
ef330312 PB |
2474 | rest_of_handle_regmove (void) |
2475 | { | |
10d22567 | 2476 | regmove_optimize (get_insns (), max_reg_num ()); |
ef330312 | 2477 | cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE); |
c2924966 | 2478 | return 0; |
ef330312 PB |
2479 | } |
2480 | ||
2481 | struct tree_opt_pass pass_regmove = | |
2482 | { | |
2483 | "regmove", /* name */ | |
2484 | gate_handle_regmove, /* gate */ | |
2485 | rest_of_handle_regmove, /* execute */ | |
2486 | NULL, /* sub */ | |
2487 | NULL, /* next */ | |
2488 | 0, /* static_pass_number */ | |
2489 | TV_REGMOVE, /* tv_id */ | |
2490 | 0, /* properties_required */ | |
2491 | 0, /* properties_provided */ | |
2492 | 0, /* properties_destroyed */ | |
2493 | 0, /* todo_flags_start */ | |
2494 | TODO_dump_func | | |
2495 | TODO_ggc_collect, /* todo_flags_finish */ | |
2496 | 'N' /* letter */ | |
2497 | }; | |
2498 | ||
2499 | ||
2500 | static bool | |
2501 | gate_handle_stack_adjustments (void) | |
2502 | { | |
2503 | return (optimize > 0); | |
2504 | } | |
2505 | ||
c2924966 | 2506 | static unsigned int |
ef330312 PB |
2507 | rest_of_handle_stack_adjustments (void) |
2508 | { | |
10d22567 | 2509 | life_analysis (PROP_POSTRELOAD); |
ef330312 PB |
2510 | cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE |
2511 | | (flag_crossjumping ? CLEANUP_CROSSJUMP : 0)); | |
2512 | ||
2513 | /* This is kind of a heuristic. We need to run combine_stack_adjustments | |
2514 | even for machines with possibly nonzero RETURN_POPS_ARGS | |
2515 | and ACCUMULATE_OUTGOING_ARGS. We expect that only ports having | |
2516 | push instructions will have popping returns. */ | |
2517 | #ifndef PUSH_ROUNDING | |
2518 | if (!ACCUMULATE_OUTGOING_ARGS) | |
2519 | #endif | |
2520 | combine_stack_adjustments (); | |
c2924966 | 2521 | return 0; |
ef330312 PB |
2522 | } |
2523 | ||
2524 | struct tree_opt_pass pass_stack_adjustments = | |
2525 | { | |
defb77dc | 2526 | "csa", /* name */ |
ef330312 PB |
2527 | gate_handle_stack_adjustments, /* gate */ |
2528 | rest_of_handle_stack_adjustments, /* execute */ | |
2529 | NULL, /* sub */ | |
2530 | NULL, /* next */ | |
2531 | 0, /* static_pass_number */ | |
2532 | 0, /* tv_id */ | |
2533 | 0, /* properties_required */ | |
2534 | 0, /* properties_provided */ | |
2535 | 0, /* properties_destroyed */ | |
2536 | 0, /* todo_flags_start */ | |
2537 | TODO_dump_func | | |
2538 | TODO_ggc_collect, /* todo_flags_finish */ | |
2539 | 0 /* letter */ | |
2540 | }; | |
2541 |