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a29c7ea6 | 1 | /* Loop unrolling and peeling. |
0397b965 | 2 | Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008, 2010, 2011 |
66647d44 | 3 | Free Software Foundation, Inc. |
a29c7ea6 ZD |
4 | |
5 | This file is part of GCC. | |
6 | ||
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 | |
9dcd6f09 | 9 | Software Foundation; either version 3, or (at your option) any later |
a29c7ea6 ZD |
10 | version. |
11 | ||
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. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
a29c7ea6 ZD |
20 | |
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
25 | #include "rtl.h" | |
26 | #include "hard-reg-set.h" | |
7932a3db | 27 | #include "obstack.h" |
a29c7ea6 ZD |
28 | #include "basic-block.h" |
29 | #include "cfgloop.h" | |
a29c7ea6 | 30 | #include "params.h" |
a29c7ea6 | 31 | #include "expr.h" |
113d659a | 32 | #include "hashtab.h" |
b8698a0f | 33 | #include "recog.h" |
40ac4f73 | 34 | #include "target.h" |
7ee2468b | 35 | #include "dumpfile.h" |
a29c7ea6 ZD |
36 | |
37 | /* This pass performs loop unrolling and peeling. We only perform these | |
e0bb17a8 | 38 | optimizations on innermost loops (with single exception) because |
a29c7ea6 ZD |
39 | the impact on performance is greatest here, and we want to avoid |
40 | unnecessary code size growth. The gain is caused by greater sequentiality | |
4d6922ee | 41 | of code, better code to optimize for further passes and in some cases |
a29c7ea6 ZD |
42 | by fewer testings of exit conditions. The main problem is code growth, |
43 | that impacts performance negatively due to effect of caches. | |
44 | ||
45 | What we do: | |
46 | ||
47 | -- complete peeling of once-rolling loops; this is the above mentioned | |
48 | exception, as this causes loop to be cancelled completely and | |
49 | does not cause code growth | |
50 | -- complete peeling of loops that roll (small) constant times. | |
51 | -- simple peeling of first iterations of loops that do not roll much | |
52 | (according to profile feedback) | |
53 | -- unrolling of loops that roll constant times; this is almost always | |
54 | win, as we get rid of exit condition tests. | |
55 | -- unrolling of loops that roll number of times that we can compute | |
56 | in runtime; we also get rid of exit condition tests here, but there | |
57 | is the extra expense for calculating the number of iterations | |
58 | -- simple unrolling of remaining loops; this is performed only if we | |
59 | are asked to, as the gain is questionable in this case and often | |
60 | it may even slow down the code | |
61 | For more detailed descriptions of each of those, see comments at | |
62 | appropriate function below. | |
63 | ||
64 | There is a lot of parameters (defined and described in params.def) that | |
65 | control how much we unroll/peel. | |
66 | ||
67 | ??? A great problem is that we don't have a good way how to determine | |
68 | how many times we should unroll the loop; the experiments I have made | |
69 | showed that this choice may affect performance in order of several %. | |
70 | */ | |
71 | ||
113d659a ZD |
72 | /* Information about induction variables to split. */ |
73 | ||
74 | struct iv_to_split | |
75 | { | |
76 | rtx insn; /* The insn in that the induction variable occurs. */ | |
77 | rtx base_var; /* The variable on that the values in the further | |
78 | iterations are based. */ | |
79 | rtx step; /* Step of the induction variable. */ | |
a9f6ecee | 80 | struct iv_to_split *next; /* Next entry in walking order. */ |
113d659a ZD |
81 | unsigned n_loc; |
82 | unsigned loc[3]; /* Location where the definition of the induction | |
83 | variable occurs in the insn. For example if | |
84 | N_LOC is 2, the expression is located at | |
b8698a0f | 85 | XEXP (XEXP (single_set, loc[0]), loc[1]). */ |
113d659a ZD |
86 | }; |
87 | ||
f37a4f14 RE |
88 | /* Information about accumulators to expand. */ |
89 | ||
90 | struct var_to_expand | |
91 | { | |
92 | rtx insn; /* The insn in that the variable expansion occurs. */ | |
471854f8 | 93 | rtx reg; /* The accumulator which is expanded. */ |
b8698a0f | 94 | VEC(rtx,heap) *var_expansions; /* The copies of the accumulator which is expanded. */ |
a9f6ecee | 95 | struct var_to_expand *next; /* Next entry in walking order. */ |
b8698a0f | 96 | enum rtx_code op; /* The type of the accumulation - addition, subtraction |
f37a4f14 RE |
97 | or multiplication. */ |
98 | int expansion_count; /* Count the number of expansions generated so far. */ | |
99 | int reuse_expansion; /* The expansion we intend to reuse to expand | |
b8698a0f L |
100 | the accumulator. If REUSE_EXPANSION is 0 reuse |
101 | the original accumulator. Else use | |
f37a4f14 RE |
102 | var_expansions[REUSE_EXPANSION - 1]. */ |
103 | }; | |
104 | ||
105 | /* Information about optimization applied in | |
106 | the unrolled loop. */ | |
107 | ||
108 | struct opt_info | |
113d659a | 109 | { |
f37a4f14 | 110 | htab_t insns_to_split; /* A hashtable of insns to split. */ |
a9f6ecee AO |
111 | struct iv_to_split *iv_to_split_head; /* The first iv to split. */ |
112 | struct iv_to_split **iv_to_split_tail; /* Pointer to the tail of the list. */ | |
f37a4f14 RE |
113 | htab_t insns_with_var_to_expand; /* A hashtable of insns with accumulators |
114 | to expand. */ | |
a9f6ecee AO |
115 | struct var_to_expand *var_to_expand_head; /* The first var to expand. */ |
116 | struct var_to_expand **var_to_expand_tail; /* Pointer to the tail of the list. */ | |
f37a4f14 RE |
117 | unsigned first_new_block; /* The first basic block that was |
118 | duplicated. */ | |
119 | basic_block loop_exit; /* The loop exit basic block. */ | |
120 | basic_block loop_preheader; /* The loop preheader basic block. */ | |
113d659a ZD |
121 | }; |
122 | ||
d73be268 ZD |
123 | static void decide_unrolling_and_peeling (int); |
124 | static void peel_loops_completely (int); | |
d47cc544 SB |
125 | static void decide_peel_simple (struct loop *, int); |
126 | static void decide_peel_once_rolling (struct loop *, int); | |
127 | static void decide_peel_completely (struct loop *, int); | |
128 | static void decide_unroll_stupid (struct loop *, int); | |
129 | static void decide_unroll_constant_iterations (struct loop *, int); | |
130 | static void decide_unroll_runtime_iterations (struct loop *, int); | |
d73be268 ZD |
131 | static void peel_loop_simple (struct loop *); |
132 | static void peel_loop_completely (struct loop *); | |
133 | static void unroll_loop_stupid (struct loop *); | |
134 | static void unroll_loop_constant_iterations (struct loop *); | |
135 | static void unroll_loop_runtime_iterations (struct loop *); | |
f37a4f14 RE |
136 | static struct opt_info *analyze_insns_in_loop (struct loop *); |
137 | static void opt_info_start_duplication (struct opt_info *); | |
138 | static void apply_opt_in_copies (struct opt_info *, unsigned, bool, bool); | |
139 | static void free_opt_info (struct opt_info *); | |
140 | static struct var_to_expand *analyze_insn_to_expand_var (struct loop*, rtx); | |
60c48e4c | 141 | static bool referenced_in_one_insn_in_loop_p (struct loop *, rtx, int *); |
f37a4f14 RE |
142 | static struct iv_to_split *analyze_iv_to_split_insn (rtx); |
143 | static void expand_var_during_unrolling (struct var_to_expand *, rtx); | |
a9f6ecee AO |
144 | static void insert_var_expansion_initialization (struct var_to_expand *, |
145 | basic_block); | |
146 | static void combine_var_copies_in_loop_exit (struct var_to_expand *, | |
147 | basic_block); | |
f37a4f14 | 148 | static rtx get_expansion (struct var_to_expand *); |
a29c7ea6 ZD |
149 | |
150 | /* Unroll and/or peel (depending on FLAGS) LOOPS. */ | |
151 | void | |
d73be268 | 152 | unroll_and_peel_loops (int flags) |
a29c7ea6 | 153 | { |
42fd6772 | 154 | struct loop *loop; |
50654f6c | 155 | bool check; |
42fd6772 | 156 | loop_iterator li; |
a29c7ea6 ZD |
157 | |
158 | /* First perform complete loop peeling (it is almost surely a win, | |
159 | and affects parameters for further decision a lot). */ | |
d73be268 | 160 | peel_loops_completely (flags); |
a29c7ea6 ZD |
161 | |
162 | /* Now decide rest of unrolling and peeling. */ | |
d73be268 | 163 | decide_unrolling_and_peeling (flags); |
a29c7ea6 | 164 | |
a29c7ea6 | 165 | /* Scan the loops, inner ones first. */ |
42fd6772 | 166 | FOR_EACH_LOOP (li, loop, LI_FROM_INNERMOST) |
a29c7ea6 | 167 | { |
50654f6c | 168 | check = true; |
a29c7ea6 ZD |
169 | /* And perform the appropriate transformations. */ |
170 | switch (loop->lpt_decision.decision) | |
171 | { | |
172 | case LPT_PEEL_COMPLETELY: | |
173 | /* Already done. */ | |
113d659a | 174 | gcc_unreachable (); |
a29c7ea6 | 175 | case LPT_PEEL_SIMPLE: |
d73be268 | 176 | peel_loop_simple (loop); |
a29c7ea6 ZD |
177 | break; |
178 | case LPT_UNROLL_CONSTANT: | |
d73be268 | 179 | unroll_loop_constant_iterations (loop); |
a29c7ea6 ZD |
180 | break; |
181 | case LPT_UNROLL_RUNTIME: | |
d73be268 | 182 | unroll_loop_runtime_iterations (loop); |
a29c7ea6 ZD |
183 | break; |
184 | case LPT_UNROLL_STUPID: | |
d73be268 | 185 | unroll_loop_stupid (loop); |
a29c7ea6 ZD |
186 | break; |
187 | case LPT_NONE: | |
50654f6c | 188 | check = false; |
a29c7ea6 ZD |
189 | break; |
190 | default: | |
113d659a | 191 | gcc_unreachable (); |
a29c7ea6 ZD |
192 | } |
193 | if (check) | |
194 | { | |
195 | #ifdef ENABLE_CHECKING | |
d73be268 | 196 | verify_loop_structure (); |
a29c7ea6 ZD |
197 | #endif |
198 | } | |
a29c7ea6 | 199 | } |
50654f6c ZD |
200 | |
201 | iv_analysis_done (); | |
202 | } | |
203 | ||
204 | /* Check whether exit of the LOOP is at the end of loop body. */ | |
205 | ||
206 | static bool | |
207 | loop_exit_at_end_p (struct loop *loop) | |
208 | { | |
209 | struct niter_desc *desc = get_simple_loop_desc (loop); | |
210 | rtx insn; | |
211 | ||
212 | if (desc->in_edge->dest != loop->latch) | |
213 | return false; | |
214 | ||
215 | /* Check that the latch is empty. */ | |
216 | FOR_BB_INSNS (loop->latch, insn) | |
217 | { | |
8efb4b35 | 218 | if (NONDEBUG_INSN_P (insn)) |
50654f6c ZD |
219 | return false; |
220 | } | |
221 | ||
222 | return true; | |
a29c7ea6 ZD |
223 | } |
224 | ||
d73be268 | 225 | /* Depending on FLAGS, check whether to peel loops completely and do so. */ |
a29c7ea6 | 226 | static void |
d73be268 | 227 | peel_loops_completely (int flags) |
a29c7ea6 | 228 | { |
2c790a28 | 229 | struct loop *loop; |
42fd6772 | 230 | loop_iterator li; |
a29c7ea6 | 231 | |
2c790a28 | 232 | /* Scan the loops, the inner ones first. */ |
42fd6772 | 233 | FOR_EACH_LOOP (li, loop, LI_FROM_INNERMOST) |
a29c7ea6 | 234 | { |
a29c7ea6 | 235 | loop->lpt_decision.decision = LPT_NONE; |
0c20a65f | 236 | |
c263766c RH |
237 | if (dump_file) |
238 | fprintf (dump_file, | |
239 | "\n;; *** Considering loop %d for complete peeling ***\n", | |
a29c7ea6 ZD |
240 | loop->num); |
241 | ||
a29c7ea6 ZD |
242 | loop->ninsns = num_loop_insns (loop); |
243 | ||
d47cc544 | 244 | decide_peel_once_rolling (loop, flags); |
a29c7ea6 | 245 | if (loop->lpt_decision.decision == LPT_NONE) |
d47cc544 | 246 | decide_peel_completely (loop, flags); |
a29c7ea6 ZD |
247 | |
248 | if (loop->lpt_decision.decision == LPT_PEEL_COMPLETELY) | |
249 | { | |
d73be268 | 250 | peel_loop_completely (loop); |
a29c7ea6 | 251 | #ifdef ENABLE_CHECKING |
d73be268 | 252 | verify_loop_structure (); |
a29c7ea6 ZD |
253 | #endif |
254 | } | |
a29c7ea6 ZD |
255 | } |
256 | } | |
257 | ||
d73be268 | 258 | /* Decide whether unroll or peel loops (depending on FLAGS) and how much. */ |
a29c7ea6 | 259 | static void |
d73be268 | 260 | decide_unrolling_and_peeling (int flags) |
a29c7ea6 | 261 | { |
42fd6772 ZD |
262 | struct loop *loop; |
263 | loop_iterator li; | |
a29c7ea6 ZD |
264 | |
265 | /* Scan the loops, inner ones first. */ | |
42fd6772 | 266 | FOR_EACH_LOOP (li, loop, LI_FROM_INNERMOST) |
a29c7ea6 | 267 | { |
a29c7ea6 ZD |
268 | loop->lpt_decision.decision = LPT_NONE; |
269 | ||
c263766c RH |
270 | if (dump_file) |
271 | fprintf (dump_file, "\n;; *** Considering loop %d ***\n", loop->num); | |
a29c7ea6 ZD |
272 | |
273 | /* Do not peel cold areas. */ | |
efd8f750 | 274 | if (optimize_loop_for_size_p (loop)) |
a29c7ea6 | 275 | { |
c263766c RH |
276 | if (dump_file) |
277 | fprintf (dump_file, ";; Not considering loop, cold area\n"); | |
a29c7ea6 ZD |
278 | continue; |
279 | } | |
280 | ||
281 | /* Can the loop be manipulated? */ | |
282 | if (!can_duplicate_loop_p (loop)) | |
283 | { | |
c263766c RH |
284 | if (dump_file) |
285 | fprintf (dump_file, | |
a29c7ea6 | 286 | ";; Not considering loop, cannot duplicate\n"); |
a29c7ea6 ZD |
287 | continue; |
288 | } | |
289 | ||
290 | /* Skip non-innermost loops. */ | |
291 | if (loop->inner) | |
292 | { | |
c263766c RH |
293 | if (dump_file) |
294 | fprintf (dump_file, ";; Not considering loop, is not innermost\n"); | |
a29c7ea6 ZD |
295 | continue; |
296 | } | |
297 | ||
298 | loop->ninsns = num_loop_insns (loop); | |
299 | loop->av_ninsns = average_num_loop_insns (loop); | |
300 | ||
301 | /* Try transformations one by one in decreasing order of | |
302 | priority. */ | |
303 | ||
d47cc544 | 304 | decide_unroll_constant_iterations (loop, flags); |
a29c7ea6 | 305 | if (loop->lpt_decision.decision == LPT_NONE) |
d47cc544 | 306 | decide_unroll_runtime_iterations (loop, flags); |
a29c7ea6 | 307 | if (loop->lpt_decision.decision == LPT_NONE) |
d47cc544 | 308 | decide_unroll_stupid (loop, flags); |
a29c7ea6 | 309 | if (loop->lpt_decision.decision == LPT_NONE) |
d47cc544 | 310 | decide_peel_simple (loop, flags); |
a29c7ea6 ZD |
311 | } |
312 | } | |
313 | ||
314 | /* Decide whether the LOOP is once rolling and suitable for complete | |
315 | peeling. */ | |
316 | static void | |
d47cc544 | 317 | decide_peel_once_rolling (struct loop *loop, int flags ATTRIBUTE_UNUSED) |
a29c7ea6 | 318 | { |
50654f6c ZD |
319 | struct niter_desc *desc; |
320 | ||
c263766c RH |
321 | if (dump_file) |
322 | fprintf (dump_file, "\n;; Considering peeling once rolling loop\n"); | |
a29c7ea6 ZD |
323 | |
324 | /* Is the loop small enough? */ | |
325 | if ((unsigned) PARAM_VALUE (PARAM_MAX_ONCE_PEELED_INSNS) < loop->ninsns) | |
326 | { | |
c263766c RH |
327 | if (dump_file) |
328 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
329 | return; |
330 | } | |
331 | ||
332 | /* Check for simple loops. */ | |
50654f6c | 333 | desc = get_simple_loop_desc (loop); |
a29c7ea6 ZD |
334 | |
335 | /* Check number of iterations. */ | |
50654f6c ZD |
336 | if (!desc->simple_p |
337 | || desc->assumptions | |
4fbe4f91 | 338 | || desc->infinite |
50654f6c | 339 | || !desc->const_iter |
e3a8f1fa JH |
340 | || (desc->niter != 0 |
341 | && max_loop_iterations_int (loop) != 0)) | |
a29c7ea6 | 342 | { |
c263766c RH |
343 | if (dump_file) |
344 | fprintf (dump_file, | |
345 | ";; Unable to prove that the loop rolls exactly once\n"); | |
a29c7ea6 ZD |
346 | return; |
347 | } | |
348 | ||
349 | /* Success. */ | |
c263766c RH |
350 | if (dump_file) |
351 | fprintf (dump_file, ";; Decided to peel exactly once rolling loop\n"); | |
a29c7ea6 ZD |
352 | loop->lpt_decision.decision = LPT_PEEL_COMPLETELY; |
353 | } | |
354 | ||
355 | /* Decide whether the LOOP is suitable for complete peeling. */ | |
356 | static void | |
d47cc544 | 357 | decide_peel_completely (struct loop *loop, int flags ATTRIBUTE_UNUSED) |
a29c7ea6 ZD |
358 | { |
359 | unsigned npeel; | |
50654f6c | 360 | struct niter_desc *desc; |
a29c7ea6 | 361 | |
c263766c RH |
362 | if (dump_file) |
363 | fprintf (dump_file, "\n;; Considering peeling completely\n"); | |
a29c7ea6 ZD |
364 | |
365 | /* Skip non-innermost loops. */ | |
366 | if (loop->inner) | |
367 | { | |
c263766c RH |
368 | if (dump_file) |
369 | fprintf (dump_file, ";; Not considering loop, is not innermost\n"); | |
a29c7ea6 ZD |
370 | return; |
371 | } | |
372 | ||
35b07080 | 373 | /* Do not peel cold areas. */ |
efd8f750 | 374 | if (optimize_loop_for_size_p (loop)) |
35b07080 | 375 | { |
c263766c RH |
376 | if (dump_file) |
377 | fprintf (dump_file, ";; Not considering loop, cold area\n"); | |
35b07080 ZD |
378 | return; |
379 | } | |
380 | ||
381 | /* Can the loop be manipulated? */ | |
382 | if (!can_duplicate_loop_p (loop)) | |
383 | { | |
c263766c RH |
384 | if (dump_file) |
385 | fprintf (dump_file, | |
35b07080 ZD |
386 | ";; Not considering loop, cannot duplicate\n"); |
387 | return; | |
388 | } | |
389 | ||
3dc575ff | 390 | /* npeel = number of iterations to peel. */ |
a29c7ea6 ZD |
391 | npeel = PARAM_VALUE (PARAM_MAX_COMPLETELY_PEELED_INSNS) / loop->ninsns; |
392 | if (npeel > (unsigned) PARAM_VALUE (PARAM_MAX_COMPLETELY_PEEL_TIMES)) | |
393 | npeel = PARAM_VALUE (PARAM_MAX_COMPLETELY_PEEL_TIMES); | |
394 | ||
395 | /* Is the loop small enough? */ | |
396 | if (!npeel) | |
397 | { | |
c263766c RH |
398 | if (dump_file) |
399 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
400 | return; |
401 | } | |
402 | ||
403 | /* Check for simple loops. */ | |
50654f6c | 404 | desc = get_simple_loop_desc (loop); |
a29c7ea6 ZD |
405 | |
406 | /* Check number of iterations. */ | |
50654f6c ZD |
407 | if (!desc->simple_p |
408 | || desc->assumptions | |
4fbe4f91 ZD |
409 | || !desc->const_iter |
410 | || desc->infinite) | |
a29c7ea6 | 411 | { |
c263766c RH |
412 | if (dump_file) |
413 | fprintf (dump_file, | |
414 | ";; Unable to prove that the loop iterates constant times\n"); | |
a29c7ea6 ZD |
415 | return; |
416 | } | |
417 | ||
50654f6c | 418 | if (desc->niter > npeel - 1) |
a29c7ea6 | 419 | { |
c263766c | 420 | if (dump_file) |
0c20a65f | 421 | { |
c263766c RH |
422 | fprintf (dump_file, |
423 | ";; Not peeling loop completely, rolls too much ("); | |
424 | fprintf (dump_file, HOST_WIDEST_INT_PRINT_DEC, desc->niter); | |
425 | fprintf (dump_file, " iterations > %d [maximum peelings])\n", npeel); | |
a29c7ea6 ZD |
426 | } |
427 | return; | |
428 | } | |
429 | ||
430 | /* Success. */ | |
c263766c RH |
431 | if (dump_file) |
432 | fprintf (dump_file, ";; Decided to peel loop completely\n"); | |
a29c7ea6 ZD |
433 | loop->lpt_decision.decision = LPT_PEEL_COMPLETELY; |
434 | } | |
435 | ||
436 | /* Peel all iterations of LOOP, remove exit edges and cancel the loop | |
437 | completely. The transformation done: | |
0c20a65f | 438 | |
a29c7ea6 ZD |
439 | for (i = 0; i < 4; i++) |
440 | body; | |
441 | ||
442 | ==> | |
0c20a65f AJ |
443 | |
444 | i = 0; | |
a29c7ea6 ZD |
445 | body; i++; |
446 | body; i++; | |
447 | body; i++; | |
448 | body; i++; | |
449 | */ | |
450 | static void | |
d73be268 | 451 | peel_loop_completely (struct loop *loop) |
a29c7ea6 ZD |
452 | { |
453 | sbitmap wont_exit; | |
454 | unsigned HOST_WIDE_INT npeel; | |
ee8c1b05 ZD |
455 | unsigned i; |
456 | VEC (edge, heap) *remove_edges; | |
457 | edge ein; | |
50654f6c | 458 | struct niter_desc *desc = get_simple_loop_desc (loop); |
f37a4f14 | 459 | struct opt_info *opt_info = NULL; |
b8698a0f | 460 | |
a29c7ea6 ZD |
461 | npeel = desc->niter; |
462 | ||
35b07080 ZD |
463 | if (npeel) |
464 | { | |
41806d92 | 465 | bool ok; |
b8698a0f | 466 | |
35b07080 | 467 | wont_exit = sbitmap_alloc (npeel + 1); |
f61e445a | 468 | bitmap_ones (wont_exit); |
35b07080 | 469 | RESET_BIT (wont_exit, 0); |
50654f6c | 470 | if (desc->noloop_assumptions) |
35b07080 ZD |
471 | RESET_BIT (wont_exit, 1); |
472 | ||
ee8c1b05 | 473 | remove_edges = NULL; |
35b07080 | 474 | |
113d659a | 475 | if (flag_split_ivs_in_unroller) |
f37a4f14 | 476 | opt_info = analyze_insns_in_loop (loop); |
b8698a0f | 477 | |
f37a4f14 | 478 | opt_info_start_duplication (opt_info); |
41806d92 | 479 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
d73be268 | 480 | npeel, |
41806d92 | 481 | wont_exit, desc->out_edge, |
ee8c1b05 | 482 | &remove_edges, |
7f7b1718 | 483 | DLTHE_FLAG_UPDATE_FREQ |
178df94f | 484 | | DLTHE_FLAG_COMPLETTE_PEEL |
7f7b1718 JH |
485 | | (opt_info |
486 | ? DLTHE_RECORD_COPY_NUMBER : 0)); | |
41806d92 | 487 | gcc_assert (ok); |
35b07080 ZD |
488 | |
489 | free (wont_exit); | |
b8698a0f | 490 | |
f37a4f14 RE |
491 | if (opt_info) |
492 | { | |
493 | apply_opt_in_copies (opt_info, npeel, false, true); | |
494 | free_opt_info (opt_info); | |
495 | } | |
113d659a | 496 | |
35b07080 | 497 | /* Remove the exit edges. */ |
ac47786e | 498 | FOR_EACH_VEC_ELT (edge, remove_edges, i, ein) |
ee8c1b05 ZD |
499 | remove_path (ein); |
500 | VEC_free (edge, heap, remove_edges); | |
35b07080 | 501 | } |
a29c7ea6 | 502 | |
628f6a4e | 503 | ein = desc->in_edge; |
50654f6c ZD |
504 | free_simple_loop_desc (loop); |
505 | ||
35b07080 ZD |
506 | /* Now remove the unreachable part of the last iteration and cancel |
507 | the loop. */ | |
d73be268 | 508 | remove_path (ein); |
a29c7ea6 | 509 | |
c263766c RH |
510 | if (dump_file) |
511 | fprintf (dump_file, ";; Peeled loop completely, %d times\n", (int) npeel); | |
a29c7ea6 ZD |
512 | } |
513 | ||
c263766c RH |
514 | /* Decide whether to unroll LOOP iterating constant number of times |
515 | and how much. */ | |
50654f6c | 516 | |
a29c7ea6 | 517 | static void |
d47cc544 | 518 | decide_unroll_constant_iterations (struct loop *loop, int flags) |
a29c7ea6 | 519 | { |
50654f6c ZD |
520 | unsigned nunroll, nunroll_by_av, best_copies, best_unroll = 0, n_copies, i; |
521 | struct niter_desc *desc; | |
e598c332 | 522 | double_int iterations; |
a29c7ea6 ZD |
523 | |
524 | if (!(flags & UAP_UNROLL)) | |
525 | { | |
526 | /* We were not asked to, just return back silently. */ | |
527 | return; | |
528 | } | |
529 | ||
c263766c RH |
530 | if (dump_file) |
531 | fprintf (dump_file, | |
532 | "\n;; Considering unrolling loop with constant " | |
533 | "number of iterations\n"); | |
a29c7ea6 ZD |
534 | |
535 | /* nunroll = total number of copies of the original loop body in | |
536 | unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */ | |
537 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns; | |
c263766c RH |
538 | nunroll_by_av |
539 | = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns; | |
a29c7ea6 ZD |
540 | if (nunroll > nunroll_by_av) |
541 | nunroll = nunroll_by_av; | |
542 | if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES)) | |
543 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES); | |
544 | ||
545 | /* Skip big loops. */ | |
546 | if (nunroll <= 1) | |
547 | { | |
c263766c RH |
548 | if (dump_file) |
549 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
550 | return; |
551 | } | |
552 | ||
553 | /* Check for simple loops. */ | |
50654f6c | 554 | desc = get_simple_loop_desc (loop); |
a29c7ea6 ZD |
555 | |
556 | /* Check number of iterations. */ | |
50654f6c | 557 | if (!desc->simple_p || !desc->const_iter || desc->assumptions) |
a29c7ea6 | 558 | { |
c263766c RH |
559 | if (dump_file) |
560 | fprintf (dump_file, | |
561 | ";; Unable to prove that the loop iterates constant times\n"); | |
a29c7ea6 ZD |
562 | return; |
563 | } | |
564 | ||
e598c332 JH |
565 | /* Check whether the loop rolls enough to consider. |
566 | Consult also loop bounds and profile; in the case the loop has more | |
567 | than one exit it may well loop less than determined maximal number | |
568 | of iterations. */ | |
569 | if (desc->niter < 2 * nunroll | |
570 | || ((estimated_loop_iterations (loop, &iterations) | |
571 | || max_loop_iterations (loop, &iterations)) | |
572 | && iterations.ult (double_int::from_shwi (2 * nunroll)))) | |
a29c7ea6 | 573 | { |
c263766c RH |
574 | if (dump_file) |
575 | fprintf (dump_file, ";; Not unrolling loop, doesn't roll\n"); | |
a29c7ea6 ZD |
576 | return; |
577 | } | |
578 | ||
579 | /* Success; now compute number of iterations to unroll. We alter | |
580 | nunroll so that as few as possible copies of loop body are | |
e0bb17a8 | 581 | necessary, while still not decreasing the number of unrollings |
a29c7ea6 ZD |
582 | too much (at most by 1). */ |
583 | best_copies = 2 * nunroll + 10; | |
584 | ||
585 | i = 2 * nunroll + 2; | |
50654f6c ZD |
586 | if (i - 1 >= desc->niter) |
587 | i = desc->niter - 2; | |
a29c7ea6 ZD |
588 | |
589 | for (; i >= nunroll - 1; i--) | |
590 | { | |
50654f6c | 591 | unsigned exit_mod = desc->niter % (i + 1); |
a29c7ea6 | 592 | |
50654f6c | 593 | if (!loop_exit_at_end_p (loop)) |
a29c7ea6 | 594 | n_copies = exit_mod + i + 1; |
50654f6c ZD |
595 | else if (exit_mod != (unsigned) i |
596 | || desc->noloop_assumptions != NULL_RTX) | |
a29c7ea6 ZD |
597 | n_copies = exit_mod + i + 2; |
598 | else | |
599 | n_copies = i + 1; | |
600 | ||
601 | if (n_copies < best_copies) | |
602 | { | |
603 | best_copies = n_copies; | |
604 | best_unroll = i; | |
605 | } | |
606 | } | |
607 | ||
a29c7ea6 ZD |
608 | loop->lpt_decision.decision = LPT_UNROLL_CONSTANT; |
609 | loop->lpt_decision.times = best_unroll; | |
b8698a0f | 610 | |
c263766c | 611 | if (dump_file) |
4fc2e37d EB |
612 | fprintf (dump_file, ";; Decided to unroll the loop %d times (%d copies).\n", |
613 | loop->lpt_decision.times, best_copies); | |
a29c7ea6 ZD |
614 | } |
615 | ||
4fc2e37d EB |
616 | /* Unroll LOOP with constant number of iterations LOOP->LPT_DECISION.TIMES times. |
617 | The transformation does this: | |
0c20a65f | 618 | |
a29c7ea6 ZD |
619 | for (i = 0; i < 102; i++) |
620 | body; | |
0c20a65f | 621 | |
4fc2e37d | 622 | ==> (LOOP->LPT_DECISION.TIMES == 3) |
0c20a65f | 623 | |
a29c7ea6 ZD |
624 | i = 0; |
625 | body; i++; | |
626 | body; i++; | |
627 | while (i < 102) | |
628 | { | |
629 | body; i++; | |
630 | body; i++; | |
631 | body; i++; | |
632 | body; i++; | |
633 | } | |
634 | */ | |
635 | static void | |
d73be268 | 636 | unroll_loop_constant_iterations (struct loop *loop) |
a29c7ea6 ZD |
637 | { |
638 | unsigned HOST_WIDE_INT niter; | |
639 | unsigned exit_mod; | |
640 | sbitmap wont_exit; | |
ee8c1b05 ZD |
641 | unsigned i; |
642 | VEC (edge, heap) *remove_edges; | |
643 | edge e; | |
a29c7ea6 | 644 | unsigned max_unroll = loop->lpt_decision.times; |
50654f6c ZD |
645 | struct niter_desc *desc = get_simple_loop_desc (loop); |
646 | bool exit_at_end = loop_exit_at_end_p (loop); | |
f37a4f14 | 647 | struct opt_info *opt_info = NULL; |
41806d92 | 648 | bool ok; |
b8698a0f | 649 | |
a29c7ea6 ZD |
650 | niter = desc->niter; |
651 | ||
113d659a ZD |
652 | /* Should not get here (such loop should be peeled instead). */ |
653 | gcc_assert (niter > max_unroll + 1); | |
a29c7ea6 ZD |
654 | |
655 | exit_mod = niter % (max_unroll + 1); | |
656 | ||
657 | wont_exit = sbitmap_alloc (max_unroll + 1); | |
f61e445a | 658 | bitmap_ones (wont_exit); |
a29c7ea6 | 659 | |
ee8c1b05 | 660 | remove_edges = NULL; |
b8698a0f | 661 | if (flag_split_ivs_in_unroller |
f37a4f14 RE |
662 | || flag_variable_expansion_in_unroller) |
663 | opt_info = analyze_insns_in_loop (loop); | |
b8698a0f | 664 | |
50654f6c | 665 | if (!exit_at_end) |
a29c7ea6 | 666 | { |
50654f6c | 667 | /* The exit is not at the end of the loop; leave exit test |
a29c7ea6 ZD |
668 | in the first copy, so that the loops that start with test |
669 | of exit condition have continuous body after unrolling. */ | |
670 | ||
c263766c | 671 | if (dump_file) |
4fc2e37d | 672 | fprintf (dump_file, ";; Condition at beginning of loop.\n"); |
a29c7ea6 ZD |
673 | |
674 | /* Peel exit_mod iterations. */ | |
675 | RESET_BIT (wont_exit, 0); | |
50654f6c | 676 | if (desc->noloop_assumptions) |
a29c7ea6 ZD |
677 | RESET_BIT (wont_exit, 1); |
678 | ||
50654f6c ZD |
679 | if (exit_mod) |
680 | { | |
f37a4f14 | 681 | opt_info_start_duplication (opt_info); |
41806d92 | 682 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
d73be268 | 683 | exit_mod, |
50654f6c | 684 | wont_exit, desc->out_edge, |
ee8c1b05 | 685 | &remove_edges, |
7f7b1718 JH |
686 | DLTHE_FLAG_UPDATE_FREQ |
687 | | (opt_info && exit_mod > 1 | |
688 | ? DLTHE_RECORD_COPY_NUMBER | |
689 | : 0)); | |
41806d92 | 690 | gcc_assert (ok); |
50654f6c | 691 | |
f37a4f14 | 692 | if (opt_info && exit_mod > 1) |
b8698a0f L |
693 | apply_opt_in_copies (opt_info, exit_mod, false, false); |
694 | ||
50654f6c ZD |
695 | desc->noloop_assumptions = NULL_RTX; |
696 | desc->niter -= exit_mod; | |
e3a8f1fa JH |
697 | loop->nb_iterations_upper_bound -= double_int::from_uhwi (exit_mod); |
698 | if (loop->any_estimate | |
699 | && double_int::from_uhwi (exit_mod).ule | |
700 | (loop->nb_iterations_estimate)) | |
701 | loop->nb_iterations_estimate -= double_int::from_uhwi (exit_mod); | |
702 | else | |
703 | loop->any_estimate = false; | |
50654f6c | 704 | } |
a29c7ea6 ZD |
705 | |
706 | SET_BIT (wont_exit, 1); | |
707 | } | |
708 | else | |
709 | { | |
710 | /* Leave exit test in last copy, for the same reason as above if | |
711 | the loop tests the condition at the end of loop body. */ | |
712 | ||
c263766c | 713 | if (dump_file) |
4fc2e37d | 714 | fprintf (dump_file, ";; Condition at end of loop.\n"); |
a29c7ea6 ZD |
715 | |
716 | /* We know that niter >= max_unroll + 2; so we do not need to care of | |
717 | case when we would exit before reaching the loop. So just peel | |
50654f6c ZD |
718 | exit_mod + 1 iterations. */ |
719 | if (exit_mod != max_unroll | |
720 | || desc->noloop_assumptions) | |
a29c7ea6 ZD |
721 | { |
722 | RESET_BIT (wont_exit, 0); | |
50654f6c | 723 | if (desc->noloop_assumptions) |
a29c7ea6 | 724 | RESET_BIT (wont_exit, 1); |
b8698a0f | 725 | |
f37a4f14 | 726 | opt_info_start_duplication (opt_info); |
41806d92 | 727 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
d73be268 | 728 | exit_mod + 1, |
41806d92 | 729 | wont_exit, desc->out_edge, |
ee8c1b05 | 730 | &remove_edges, |
7f7b1718 JH |
731 | DLTHE_FLAG_UPDATE_FREQ |
732 | | (opt_info && exit_mod > 0 | |
733 | ? DLTHE_RECORD_COPY_NUMBER | |
734 | : 0)); | |
41806d92 | 735 | gcc_assert (ok); |
b8698a0f | 736 | |
f37a4f14 RE |
737 | if (opt_info && exit_mod > 0) |
738 | apply_opt_in_copies (opt_info, exit_mod + 1, false, false); | |
113d659a | 739 | |
50654f6c | 740 | desc->niter -= exit_mod + 1; |
73367f92 | 741 | loop->nb_iterations_upper_bound -= double_int::from_uhwi (exit_mod + 1); |
e3a8f1fa JH |
742 | if (loop->any_estimate |
743 | && double_int::from_uhwi (exit_mod + 1).ule | |
744 | (loop->nb_iterations_estimate)) | |
745 | loop->nb_iterations_estimate -= double_int::from_uhwi (exit_mod + 1); | |
746 | else | |
747 | loop->any_estimate = false; | |
50654f6c ZD |
748 | desc->noloop_assumptions = NULL_RTX; |
749 | ||
a29c7ea6 ZD |
750 | SET_BIT (wont_exit, 0); |
751 | SET_BIT (wont_exit, 1); | |
752 | } | |
753 | ||
754 | RESET_BIT (wont_exit, max_unroll); | |
755 | } | |
756 | ||
757 | /* Now unroll the loop. */ | |
b8698a0f | 758 | |
f37a4f14 | 759 | opt_info_start_duplication (opt_info); |
41806d92 | 760 | ok = duplicate_loop_to_header_edge (loop, loop_latch_edge (loop), |
d73be268 | 761 | max_unroll, |
41806d92 | 762 | wont_exit, desc->out_edge, |
ee8c1b05 | 763 | &remove_edges, |
7f7b1718 JH |
764 | DLTHE_FLAG_UPDATE_FREQ |
765 | | (opt_info | |
766 | ? DLTHE_RECORD_COPY_NUMBER | |
767 | : 0)); | |
41806d92 | 768 | gcc_assert (ok); |
a29c7ea6 | 769 | |
f37a4f14 | 770 | if (opt_info) |
113d659a | 771 | { |
f37a4f14 RE |
772 | apply_opt_in_copies (opt_info, max_unroll, true, true); |
773 | free_opt_info (opt_info); | |
113d659a ZD |
774 | } |
775 | ||
a29c7ea6 ZD |
776 | free (wont_exit); |
777 | ||
50654f6c ZD |
778 | if (exit_at_end) |
779 | { | |
6580ee77 | 780 | basic_block exit_block = get_bb_copy (desc->in_edge->src); |
50654f6c | 781 | /* Find a new in and out edge; they are in the last copy we have made. */ |
b8698a0f | 782 | |
628f6a4e | 783 | if (EDGE_SUCC (exit_block, 0)->dest == desc->out_edge->dest) |
50654f6c | 784 | { |
628f6a4e BE |
785 | desc->out_edge = EDGE_SUCC (exit_block, 0); |
786 | desc->in_edge = EDGE_SUCC (exit_block, 1); | |
50654f6c ZD |
787 | } |
788 | else | |
789 | { | |
628f6a4e BE |
790 | desc->out_edge = EDGE_SUCC (exit_block, 1); |
791 | desc->in_edge = EDGE_SUCC (exit_block, 0); | |
50654f6c ZD |
792 | } |
793 | } | |
794 | ||
795 | desc->niter /= max_unroll + 1; | |
e3a8f1fa | 796 | loop->nb_iterations_upper_bound |
73367f92 | 797 | = loop->nb_iterations_upper_bound.udiv (double_int::from_uhwi (max_unroll |
e3a8f1fa | 798 | + 1), |
73367f92 | 799 | TRUNC_DIV_EXPR); |
e3a8f1fa JH |
800 | if (loop->any_estimate) |
801 | loop->nb_iterations_estimate | |
73367f92 | 802 | = loop->nb_iterations_estimate.udiv (double_int::from_uhwi (max_unroll |
e3a8f1fa | 803 | + 1), |
73367f92 | 804 | TRUNC_DIV_EXPR); |
50654f6c ZD |
805 | desc->niter_expr = GEN_INT (desc->niter); |
806 | ||
a29c7ea6 | 807 | /* Remove the edges. */ |
ac47786e | 808 | FOR_EACH_VEC_ELT (edge, remove_edges, i, e) |
ee8c1b05 ZD |
809 | remove_path (e); |
810 | VEC_free (edge, heap, remove_edges); | |
a29c7ea6 | 811 | |
c263766c RH |
812 | if (dump_file) |
813 | fprintf (dump_file, | |
814 | ";; Unrolled loop %d times, constant # of iterations %i insns\n", | |
815 | max_unroll, num_loop_insns (loop)); | |
a29c7ea6 ZD |
816 | } |
817 | ||
818 | /* Decide whether to unroll LOOP iterating runtime computable number of times | |
819 | and how much. */ | |
820 | static void | |
d47cc544 | 821 | decide_unroll_runtime_iterations (struct loop *loop, int flags) |
a29c7ea6 ZD |
822 | { |
823 | unsigned nunroll, nunroll_by_av, i; | |
50654f6c | 824 | struct niter_desc *desc; |
e3a8f1fa | 825 | double_int iterations; |
a29c7ea6 ZD |
826 | |
827 | if (!(flags & UAP_UNROLL)) | |
828 | { | |
829 | /* We were not asked to, just return back silently. */ | |
830 | return; | |
831 | } | |
832 | ||
c263766c RH |
833 | if (dump_file) |
834 | fprintf (dump_file, | |
835 | "\n;; Considering unrolling loop with runtime " | |
836 | "computable number of iterations\n"); | |
a29c7ea6 ZD |
837 | |
838 | /* nunroll = total number of copies of the original loop body in | |
839 | unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */ | |
840 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns; | |
841 | nunroll_by_av = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns; | |
842 | if (nunroll > nunroll_by_av) | |
843 | nunroll = nunroll_by_av; | |
844 | if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES)) | |
845 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES); | |
846 | ||
40ac4f73 CB |
847 | if (targetm.loop_unroll_adjust) |
848 | nunroll = targetm.loop_unroll_adjust (nunroll, loop); | |
849 | ||
a29c7ea6 ZD |
850 | /* Skip big loops. */ |
851 | if (nunroll <= 1) | |
852 | { | |
c263766c RH |
853 | if (dump_file) |
854 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
855 | return; |
856 | } | |
857 | ||
858 | /* Check for simple loops. */ | |
50654f6c | 859 | desc = get_simple_loop_desc (loop); |
a29c7ea6 ZD |
860 | |
861 | /* Check simpleness. */ | |
50654f6c | 862 | if (!desc->simple_p || desc->assumptions) |
a29c7ea6 | 863 | { |
c263766c RH |
864 | if (dump_file) |
865 | fprintf (dump_file, | |
866 | ";; Unable to prove that the number of iterations " | |
867 | "can be counted in runtime\n"); | |
a29c7ea6 ZD |
868 | return; |
869 | } | |
870 | ||
50654f6c | 871 | if (desc->const_iter) |
a29c7ea6 | 872 | { |
c263766c RH |
873 | if (dump_file) |
874 | fprintf (dump_file, ";; Loop iterates constant times\n"); | |
a29c7ea6 ZD |
875 | return; |
876 | } | |
877 | ||
73367f92 | 878 | /* Check whether the loop rolls. */ |
e3a8f1fa JH |
879 | if ((estimated_loop_iterations (loop, &iterations) |
880 | || max_loop_iterations (loop, &iterations)) | |
73367f92 | 881 | && iterations.ult (double_int::from_shwi (2 * nunroll))) |
a29c7ea6 | 882 | { |
c263766c RH |
883 | if (dump_file) |
884 | fprintf (dump_file, ";; Not unrolling loop, doesn't roll\n"); | |
a29c7ea6 ZD |
885 | return; |
886 | } | |
887 | ||
888 | /* Success; now force nunroll to be power of 2, as we are unable to | |
889 | cope with overflows in computation of number of iterations. */ | |
50654f6c ZD |
890 | for (i = 1; 2 * i <= nunroll; i *= 2) |
891 | continue; | |
a29c7ea6 ZD |
892 | |
893 | loop->lpt_decision.decision = LPT_UNROLL_RUNTIME; | |
894 | loop->lpt_decision.times = i - 1; | |
b8698a0f | 895 | |
c263766c | 896 | if (dump_file) |
4fc2e37d | 897 | fprintf (dump_file, ";; Decided to unroll the loop %d times.\n", |
50654f6c | 898 | loop->lpt_decision.times); |
a29c7ea6 ZD |
899 | } |
900 | ||
7d93d987 ZD |
901 | /* Splits edge E and inserts the sequence of instructions INSNS on it, and |
902 | returns the newly created block. If INSNS is NULL_RTX, nothing is changed | |
903 | and NULL is returned instead. */ | |
598ec7bd ZD |
904 | |
905 | basic_block | |
906 | split_edge_and_insert (edge e, rtx insns) | |
907 | { | |
7d93d987 ZD |
908 | basic_block bb; |
909 | ||
910 | if (!insns) | |
911 | return NULL; | |
b8698a0f | 912 | bb = split_edge (e); |
598ec7bd | 913 | emit_insn_after (insns, BB_END (bb)); |
7984c787 SB |
914 | |
915 | /* ??? We used to assume that INSNS can contain control flow insns, and | |
916 | that we had to try to find sub basic blocks in BB to maintain a valid | |
917 | CFG. For this purpose we used to set the BB_SUPERBLOCK flag on BB | |
918 | and call break_superblocks when going out of cfglayout mode. But it | |
919 | turns out that this never happens; and that if it does ever happen, | |
c7dd803e | 920 | the TODO_verify_flow at the end of the RTL loop passes would fail. |
7984c787 SB |
921 | |
922 | There are two reasons why we expected we could have control flow insns | |
923 | in INSNS. The first is when a comparison has to be done in parts, and | |
924 | the second is when the number of iterations is computed for loops with | |
925 | the number of iterations known at runtime. In both cases, test cases | |
926 | to get control flow in INSNS appear to be impossible to construct: | |
927 | ||
928 | * If do_compare_rtx_and_jump needs several branches to do comparison | |
929 | in a mode that needs comparison by parts, we cannot analyze the | |
930 | number of iterations of the loop, and we never get to unrolling it. | |
931 | ||
932 | * The code in expand_divmod that was suspected to cause creation of | |
933 | branching code seems to be only accessed for signed division. The | |
934 | divisions used by # of iterations analysis are always unsigned. | |
935 | Problems might arise on architectures that emits branching code | |
936 | for some operations that may appear in the unroller (especially | |
937 | for division), but we have no such architectures. | |
938 | ||
939 | Considering all this, it was decided that we should for now assume | |
940 | that INSNS can in theory contain control flow insns, but in practice | |
941 | it never does. So we don't handle the theoretical case, and should | |
942 | a real failure ever show up, we have a pretty good clue for how to | |
943 | fix it. */ | |
944 | ||
598ec7bd ZD |
945 | return bb; |
946 | } | |
947 | ||
4fc2e37d EB |
948 | /* Unroll LOOP for which we are able to count number of iterations in runtime |
949 | LOOP->LPT_DECISION.TIMES times. The transformation does this (with some | |
a29c7ea6 | 950 | extra care for case n < 0): |
0c20a65f | 951 | |
a29c7ea6 ZD |
952 | for (i = 0; i < n; i++) |
953 | body; | |
0c20a65f | 954 | |
4fc2e37d | 955 | ==> (LOOP->LPT_DECISION.TIMES == 3) |
0c20a65f | 956 | |
a29c7ea6 ZD |
957 | i = 0; |
958 | mod = n % 4; | |
0c20a65f | 959 | |
a29c7ea6 ZD |
960 | switch (mod) |
961 | { | |
962 | case 3: | |
963 | body; i++; | |
964 | case 2: | |
965 | body; i++; | |
966 | case 1: | |
967 | body; i++; | |
968 | case 0: ; | |
969 | } | |
0c20a65f | 970 | |
a29c7ea6 ZD |
971 | while (i < n) |
972 | { | |
973 | body; i++; | |
974 | body; i++; | |
975 | body; i++; | |
976 | body; i++; | |
977 | } | |
978 | */ | |
979 | static void | |
d73be268 | 980 | unroll_loop_runtime_iterations (struct loop *loop) |
a29c7ea6 | 981 | { |
50654f6c | 982 | rtx old_niter, niter, init_code, branch_code, tmp; |
a29c7ea6 | 983 | unsigned i, j, p; |
66f97d31 ZD |
984 | basic_block preheader, *body, swtch, ezc_swtch; |
985 | VEC (basic_block, heap) *dom_bbs; | |
a29c7ea6 ZD |
986 | sbitmap wont_exit; |
987 | int may_exit_copy; | |
ee8c1b05 ZD |
988 | unsigned n_peel; |
989 | VEC (edge, heap) *remove_edges; | |
990 | edge e; | |
a29c7ea6 ZD |
991 | bool extra_zero_check, last_may_exit; |
992 | unsigned max_unroll = loop->lpt_decision.times; | |
50654f6c ZD |
993 | struct niter_desc *desc = get_simple_loop_desc (loop); |
994 | bool exit_at_end = loop_exit_at_end_p (loop); | |
f37a4f14 | 995 | struct opt_info *opt_info = NULL; |
41806d92 | 996 | bool ok; |
b8698a0f | 997 | |
f37a4f14 RE |
998 | if (flag_split_ivs_in_unroller |
999 | || flag_variable_expansion_in_unroller) | |
1000 | opt_info = analyze_insns_in_loop (loop); | |
b8698a0f | 1001 | |
a29c7ea6 | 1002 | /* Remember blocks whose dominators will have to be updated. */ |
66f97d31 | 1003 | dom_bbs = NULL; |
a29c7ea6 ZD |
1004 | |
1005 | body = get_loop_body (loop); | |
1006 | for (i = 0; i < loop->num_nodes; i++) | |
1007 | { | |
66f97d31 ZD |
1008 | VEC (basic_block, heap) *ldom; |
1009 | basic_block bb; | |
a29c7ea6 | 1010 | |
66f97d31 | 1011 | ldom = get_dominated_by (CDI_DOMINATORS, body[i]); |
ac47786e | 1012 | FOR_EACH_VEC_ELT (basic_block, ldom, j, bb) |
66f97d31 ZD |
1013 | if (!flow_bb_inside_loop_p (loop, bb)) |
1014 | VEC_safe_push (basic_block, heap, dom_bbs, bb); | |
a29c7ea6 | 1015 | |
66f97d31 | 1016 | VEC_free (basic_block, heap, ldom); |
a29c7ea6 ZD |
1017 | } |
1018 | free (body); | |
1019 | ||
50654f6c | 1020 | if (!exit_at_end) |
a29c7ea6 ZD |
1021 | { |
1022 | /* Leave exit in first copy (for explanation why see comment in | |
1023 | unroll_loop_constant_iterations). */ | |
1024 | may_exit_copy = 0; | |
1025 | n_peel = max_unroll - 1; | |
1026 | extra_zero_check = true; | |
1027 | last_may_exit = false; | |
1028 | } | |
1029 | else | |
1030 | { | |
1031 | /* Leave exit in last copy (for explanation why see comment in | |
1032 | unroll_loop_constant_iterations). */ | |
1033 | may_exit_copy = max_unroll; | |
1034 | n_peel = max_unroll; | |
1035 | extra_zero_check = false; | |
1036 | last_may_exit = true; | |
1037 | } | |
1038 | ||
1039 | /* Get expression for number of iterations. */ | |
1040 | start_sequence (); | |
50654f6c ZD |
1041 | old_niter = niter = gen_reg_rtx (desc->mode); |
1042 | tmp = force_operand (copy_rtx (desc->niter_expr), niter); | |
1043 | if (tmp != niter) | |
1044 | emit_move_insn (niter, tmp); | |
a29c7ea6 ZD |
1045 | |
1046 | /* Count modulo by ANDing it with max_unroll; we use the fact that | |
1047 | the number of unrollings is a power of two, and thus this is correct | |
1048 | even if there is overflow in the computation. */ | |
50654f6c | 1049 | niter = expand_simple_binop (desc->mode, AND, |
a29c7ea6 ZD |
1050 | niter, |
1051 | GEN_INT (max_unroll), | |
1052 | NULL_RTX, 0, OPTAB_LIB_WIDEN); | |
1053 | ||
1054 | init_code = get_insns (); | |
1055 | end_sequence (); | |
2ed22578 | 1056 | unshare_all_rtl_in_chain (init_code); |
a29c7ea6 ZD |
1057 | |
1058 | /* Precondition the loop. */ | |
598ec7bd | 1059 | split_edge_and_insert (loop_preheader_edge (loop), init_code); |
a29c7ea6 | 1060 | |
ee8c1b05 | 1061 | remove_edges = NULL; |
a29c7ea6 ZD |
1062 | |
1063 | wont_exit = sbitmap_alloc (max_unroll + 2); | |
1064 | ||
1065 | /* Peel the first copy of loop body (almost always we must leave exit test | |
1066 | here; the only exception is when we have extra zero check and the number | |
50654f6c ZD |
1067 | of iterations is reliable. Also record the place of (possible) extra |
1068 | zero check. */ | |
f61e445a | 1069 | bitmap_clear (wont_exit); |
50654f6c ZD |
1070 | if (extra_zero_check |
1071 | && !desc->noloop_assumptions) | |
a29c7ea6 ZD |
1072 | SET_BIT (wont_exit, 1); |
1073 | ezc_swtch = loop_preheader_edge (loop)->src; | |
41806d92 | 1074 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
d73be268 | 1075 | 1, wont_exit, desc->out_edge, |
ee8c1b05 | 1076 | &remove_edges, |
41806d92 NS |
1077 | DLTHE_FLAG_UPDATE_FREQ); |
1078 | gcc_assert (ok); | |
a29c7ea6 ZD |
1079 | |
1080 | /* Record the place where switch will be built for preconditioning. */ | |
598ec7bd | 1081 | swtch = split_edge (loop_preheader_edge (loop)); |
a29c7ea6 ZD |
1082 | |
1083 | for (i = 0; i < n_peel; i++) | |
1084 | { | |
1085 | /* Peel the copy. */ | |
f61e445a | 1086 | bitmap_clear (wont_exit); |
a29c7ea6 ZD |
1087 | if (i != n_peel - 1 || !last_may_exit) |
1088 | SET_BIT (wont_exit, 1); | |
41806d92 | 1089 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
d73be268 | 1090 | 1, wont_exit, desc->out_edge, |
ee8c1b05 | 1091 | &remove_edges, |
41806d92 NS |
1092 | DLTHE_FLAG_UPDATE_FREQ); |
1093 | gcc_assert (ok); | |
a29c7ea6 | 1094 | |
91f4cfe3 ZD |
1095 | /* Create item for switch. */ |
1096 | j = n_peel - i - (extra_zero_check ? 0 : 1); | |
1097 | p = REG_BR_PROB_BASE / (i + 2); | |
1098 | ||
598ec7bd | 1099 | preheader = split_edge (loop_preheader_edge (loop)); |
50654f6c | 1100 | branch_code = compare_and_jump_seq (copy_rtx (niter), GEN_INT (j), EQ, |
41806d92 NS |
1101 | block_label (preheader), p, |
1102 | NULL_RTX); | |
91f4cfe3 | 1103 | |
7d93d987 ZD |
1104 | /* We rely on the fact that the compare and jump cannot be optimized out, |
1105 | and hence the cfg we create is correct. */ | |
1106 | gcc_assert (branch_code != NULL_RTX); | |
1107 | ||
598ec7bd | 1108 | swtch = split_edge_and_insert (single_pred_edge (swtch), branch_code); |
d47cc544 | 1109 | set_immediate_dominator (CDI_DOMINATORS, preheader, swtch); |
c5cbcccf | 1110 | single_pred_edge (swtch)->probability = REG_BR_PROB_BASE - p; |
91f4cfe3 | 1111 | e = make_edge (swtch, preheader, |
c5cbcccf | 1112 | single_succ_edge (swtch)->flags & EDGE_IRREDUCIBLE_LOOP); |
e3a8f1fa | 1113 | e->count = RDIV (preheader->count * REG_BR_PROB_BASE, p); |
91f4cfe3 | 1114 | e->probability = p; |
a29c7ea6 ZD |
1115 | } |
1116 | ||
1117 | if (extra_zero_check) | |
1118 | { | |
1119 | /* Add branch for zero iterations. */ | |
1120 | p = REG_BR_PROB_BASE / (max_unroll + 1); | |
1121 | swtch = ezc_swtch; | |
598ec7bd | 1122 | preheader = split_edge (loop_preheader_edge (loop)); |
50654f6c | 1123 | branch_code = compare_and_jump_seq (copy_rtx (niter), const0_rtx, EQ, |
41806d92 NS |
1124 | block_label (preheader), p, |
1125 | NULL_RTX); | |
7d93d987 | 1126 | gcc_assert (branch_code != NULL_RTX); |
a29c7ea6 | 1127 | |
598ec7bd | 1128 | swtch = split_edge_and_insert (single_succ_edge (swtch), branch_code); |
d47cc544 | 1129 | set_immediate_dominator (CDI_DOMINATORS, preheader, swtch); |
c5cbcccf | 1130 | single_succ_edge (swtch)->probability = REG_BR_PROB_BASE - p; |
72b8d451 | 1131 | e = make_edge (swtch, preheader, |
c5cbcccf | 1132 | single_succ_edge (swtch)->flags & EDGE_IRREDUCIBLE_LOOP); |
e3a8f1fa | 1133 | e->count = RDIV (preheader->count * REG_BR_PROB_BASE, p); |
a29c7ea6 ZD |
1134 | e->probability = p; |
1135 | } | |
1136 | ||
1137 | /* Recount dominators for outer blocks. */ | |
66f97d31 | 1138 | iterate_fix_dominators (CDI_DOMINATORS, dom_bbs, false); |
a29c7ea6 ZD |
1139 | |
1140 | /* And unroll loop. */ | |
1141 | ||
f61e445a | 1142 | bitmap_ones (wont_exit); |
a29c7ea6 | 1143 | RESET_BIT (wont_exit, may_exit_copy); |
f37a4f14 | 1144 | opt_info_start_duplication (opt_info); |
b8698a0f | 1145 | |
41806d92 | 1146 | ok = duplicate_loop_to_header_edge (loop, loop_latch_edge (loop), |
d73be268 | 1147 | max_unroll, |
41806d92 | 1148 | wont_exit, desc->out_edge, |
ee8c1b05 | 1149 | &remove_edges, |
7f7b1718 JH |
1150 | DLTHE_FLAG_UPDATE_FREQ |
1151 | | (opt_info | |
1152 | ? DLTHE_RECORD_COPY_NUMBER | |
1153 | : 0)); | |
41806d92 | 1154 | gcc_assert (ok); |
b8698a0f | 1155 | |
f37a4f14 | 1156 | if (opt_info) |
113d659a | 1157 | { |
f37a4f14 RE |
1158 | apply_opt_in_copies (opt_info, max_unroll, true, true); |
1159 | free_opt_info (opt_info); | |
113d659a ZD |
1160 | } |
1161 | ||
a29c7ea6 ZD |
1162 | free (wont_exit); |
1163 | ||
50654f6c ZD |
1164 | if (exit_at_end) |
1165 | { | |
6580ee77 | 1166 | basic_block exit_block = get_bb_copy (desc->in_edge->src); |
41806d92 NS |
1167 | /* Find a new in and out edge; they are in the last copy we have |
1168 | made. */ | |
b8698a0f | 1169 | |
628f6a4e | 1170 | if (EDGE_SUCC (exit_block, 0)->dest == desc->out_edge->dest) |
50654f6c | 1171 | { |
628f6a4e BE |
1172 | desc->out_edge = EDGE_SUCC (exit_block, 0); |
1173 | desc->in_edge = EDGE_SUCC (exit_block, 1); | |
50654f6c ZD |
1174 | } |
1175 | else | |
1176 | { | |
628f6a4e BE |
1177 | desc->out_edge = EDGE_SUCC (exit_block, 1); |
1178 | desc->in_edge = EDGE_SUCC (exit_block, 0); | |
50654f6c ZD |
1179 | } |
1180 | } | |
1181 | ||
a29c7ea6 | 1182 | /* Remove the edges. */ |
ac47786e | 1183 | FOR_EACH_VEC_ELT (edge, remove_edges, i, e) |
ee8c1b05 ZD |
1184 | remove_path (e); |
1185 | VEC_free (edge, heap, remove_edges); | |
a29c7ea6 | 1186 | |
50654f6c ZD |
1187 | /* We must be careful when updating the number of iterations due to |
1188 | preconditioning and the fact that the value must be valid at entry | |
1189 | of the loop. After passing through the above code, we see that | |
1190 | the correct new number of iterations is this: */ | |
113d659a | 1191 | gcc_assert (!desc->const_iter); |
50654f6c | 1192 | desc->niter_expr = |
41806d92 NS |
1193 | simplify_gen_binary (UDIV, desc->mode, old_niter, |
1194 | GEN_INT (max_unroll + 1)); | |
e3a8f1fa JH |
1195 | loop->nb_iterations_upper_bound |
1196 | = loop->nb_iterations_upper_bound.udiv (double_int::from_uhwi (max_unroll | |
1197 | + 1), | |
73367f92 | 1198 | TRUNC_DIV_EXPR); |
e3a8f1fa JH |
1199 | if (loop->any_estimate) |
1200 | loop->nb_iterations_estimate | |
1201 | = loop->nb_iterations_estimate.udiv (double_int::from_uhwi (max_unroll | |
1202 | + 1), | |
73367f92 | 1203 | TRUNC_DIV_EXPR); |
50654f6c ZD |
1204 | if (exit_at_end) |
1205 | { | |
1206 | desc->niter_expr = | |
1207 | simplify_gen_binary (MINUS, desc->mode, desc->niter_expr, const1_rtx); | |
1208 | desc->noloop_assumptions = NULL_RTX; | |
e3a8f1fa JH |
1209 | --loop->nb_iterations_upper_bound; |
1210 | if (loop->any_estimate | |
1211 | && loop->nb_iterations_estimate != double_int_zero) | |
1212 | --loop->nb_iterations_estimate; | |
1213 | else | |
1214 | loop->any_estimate = false; | |
50654f6c ZD |
1215 | } |
1216 | ||
c263766c RH |
1217 | if (dump_file) |
1218 | fprintf (dump_file, | |
1219 | ";; Unrolled loop %d times, counting # of iterations " | |
1220 | "in runtime, %i insns\n", | |
a29c7ea6 | 1221 | max_unroll, num_loop_insns (loop)); |
b6cdba27 | 1222 | |
66f97d31 | 1223 | VEC_free (basic_block, heap, dom_bbs); |
a29c7ea6 | 1224 | } |
0c20a65f | 1225 | |
a29c7ea6 ZD |
1226 | /* Decide whether to simply peel LOOP and how much. */ |
1227 | static void | |
d47cc544 | 1228 | decide_peel_simple (struct loop *loop, int flags) |
a29c7ea6 ZD |
1229 | { |
1230 | unsigned npeel; | |
e3a8f1fa | 1231 | double_int iterations; |
a29c7ea6 ZD |
1232 | |
1233 | if (!(flags & UAP_PEEL)) | |
1234 | { | |
1235 | /* We were not asked to, just return back silently. */ | |
1236 | return; | |
1237 | } | |
1238 | ||
c263766c RH |
1239 | if (dump_file) |
1240 | fprintf (dump_file, "\n;; Considering simply peeling loop\n"); | |
a29c7ea6 | 1241 | |
3dc575ff | 1242 | /* npeel = number of iterations to peel. */ |
a29c7ea6 ZD |
1243 | npeel = PARAM_VALUE (PARAM_MAX_PEELED_INSNS) / loop->ninsns; |
1244 | if (npeel > (unsigned) PARAM_VALUE (PARAM_MAX_PEEL_TIMES)) | |
1245 | npeel = PARAM_VALUE (PARAM_MAX_PEEL_TIMES); | |
1246 | ||
1247 | /* Skip big loops. */ | |
1248 | if (!npeel) | |
1249 | { | |
c263766c RH |
1250 | if (dump_file) |
1251 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
1252 | return; |
1253 | } | |
1254 | ||
a29c7ea6 | 1255 | /* Do not simply peel loops with branches inside -- it increases number |
6acf25e4 JH |
1256 | of mispredicts. |
1257 | Exception is when we do have profile and we however have good chance | |
1258 | to peel proper number of iterations loop will iterate in practice. | |
1259 | TODO: this heuristic needs tunning; while for complette unrolling | |
1260 | the branch inside loop mostly eliminates any improvements, for | |
1261 | peeling it is not the case. Also a function call inside loop is | |
1262 | also branch from branch prediction POV (and probably better reason | |
1263 | to not unroll/peel). */ | |
1264 | if (num_loop_branches (loop) > 1 | |
1265 | && profile_status != PROFILE_READ) | |
a29c7ea6 | 1266 | { |
c263766c RH |
1267 | if (dump_file) |
1268 | fprintf (dump_file, ";; Not peeling, contains branches\n"); | |
a29c7ea6 ZD |
1269 | return; |
1270 | } | |
1271 | ||
e3a8f1fa JH |
1272 | /* If we have realistic estimate on number of iterations, use it. */ |
1273 | if (estimated_loop_iterations (loop, &iterations)) | |
a29c7ea6 | 1274 | { |
73367f92 | 1275 | if (double_int::from_shwi (npeel).ule (iterations)) |
a29c7ea6 | 1276 | { |
c263766c | 1277 | if (dump_file) |
a29c7ea6 | 1278 | { |
c263766c RH |
1279 | fprintf (dump_file, ";; Not peeling loop, rolls too much ("); |
1280 | fprintf (dump_file, HOST_WIDEST_INT_PRINT_DEC, | |
e3a8f1fa | 1281 | (HOST_WIDEST_INT) (iterations.to_shwi () + 1)); |
c263766c RH |
1282 | fprintf (dump_file, " iterations > %d [maximum peelings])\n", |
1283 | npeel); | |
a29c7ea6 ZD |
1284 | } |
1285 | return; | |
1286 | } | |
e3a8f1fa | 1287 | npeel = iterations.to_shwi () + 1; |
a29c7ea6 | 1288 | } |
e3a8f1fa JH |
1289 | /* If we have small enough bound on iterations, we can still peel (completely |
1290 | unroll). */ | |
1291 | else if (max_loop_iterations (loop, &iterations) | |
73367f92 | 1292 | && iterations.ult (double_int::from_shwi (npeel))) |
e3a8f1fa | 1293 | npeel = iterations.to_shwi () + 1; |
a29c7ea6 ZD |
1294 | else |
1295 | { | |
1296 | /* For now we have no good heuristics to decide whether loop peeling | |
1297 | will be effective, so disable it. */ | |
c263766c RH |
1298 | if (dump_file) |
1299 | fprintf (dump_file, | |
a29c7ea6 ZD |
1300 | ";; Not peeling loop, no evidence it will be profitable\n"); |
1301 | return; | |
1302 | } | |
1303 | ||
1304 | /* Success. */ | |
1305 | loop->lpt_decision.decision = LPT_PEEL_SIMPLE; | |
1306 | loop->lpt_decision.times = npeel; | |
b8698a0f | 1307 | |
c263766c | 1308 | if (dump_file) |
4fc2e37d | 1309 | fprintf (dump_file, ";; Decided to simply peel the loop %d times.\n", |
50654f6c | 1310 | loop->lpt_decision.times); |
a29c7ea6 ZD |
1311 | } |
1312 | ||
4fc2e37d EB |
1313 | /* Peel a LOOP LOOP->LPT_DECISION.TIMES times. The transformation does this: |
1314 | ||
a29c7ea6 ZD |
1315 | while (cond) |
1316 | body; | |
1317 | ||
4fc2e37d | 1318 | ==> (LOOP->LPT_DECISION.TIMES == 3) |
a29c7ea6 ZD |
1319 | |
1320 | if (!cond) goto end; | |
1321 | body; | |
1322 | if (!cond) goto end; | |
1323 | body; | |
4fc2e37d EB |
1324 | if (!cond) goto end; |
1325 | body; | |
a29c7ea6 ZD |
1326 | while (cond) |
1327 | body; | |
1328 | end: ; | |
1329 | */ | |
1330 | static void | |
d73be268 | 1331 | peel_loop_simple (struct loop *loop) |
a29c7ea6 ZD |
1332 | { |
1333 | sbitmap wont_exit; | |
1334 | unsigned npeel = loop->lpt_decision.times; | |
50654f6c | 1335 | struct niter_desc *desc = get_simple_loop_desc (loop); |
f37a4f14 | 1336 | struct opt_info *opt_info = NULL; |
41806d92 | 1337 | bool ok; |
b8698a0f | 1338 | |
113d659a | 1339 | if (flag_split_ivs_in_unroller && npeel > 1) |
f37a4f14 | 1340 | opt_info = analyze_insns_in_loop (loop); |
b8698a0f | 1341 | |
a29c7ea6 | 1342 | wont_exit = sbitmap_alloc (npeel + 1); |
f61e445a | 1343 | bitmap_clear (wont_exit); |
b8698a0f | 1344 | |
f37a4f14 | 1345 | opt_info_start_duplication (opt_info); |
b8698a0f | 1346 | |
41806d92 | 1347 | ok = duplicate_loop_to_header_edge (loop, loop_preheader_edge (loop), |
ee8c1b05 | 1348 | npeel, wont_exit, NULL, |
7f7b1718 JH |
1349 | NULL, DLTHE_FLAG_UPDATE_FREQ |
1350 | | (opt_info | |
1351 | ? DLTHE_RECORD_COPY_NUMBER | |
1352 | : 0)); | |
41806d92 | 1353 | gcc_assert (ok); |
0c20a65f | 1354 | |
a29c7ea6 | 1355 | free (wont_exit); |
b8698a0f | 1356 | |
f37a4f14 | 1357 | if (opt_info) |
113d659a | 1358 | { |
f37a4f14 RE |
1359 | apply_opt_in_copies (opt_info, npeel, false, false); |
1360 | free_opt_info (opt_info); | |
113d659a ZD |
1361 | } |
1362 | ||
50654f6c ZD |
1363 | if (desc->simple_p) |
1364 | { | |
1365 | if (desc->const_iter) | |
1366 | { | |
1367 | desc->niter -= npeel; | |
1368 | desc->niter_expr = GEN_INT (desc->niter); | |
1369 | desc->noloop_assumptions = NULL_RTX; | |
1370 | } | |
1371 | else | |
1372 | { | |
1373 | /* We cannot just update niter_expr, as its value might be clobbered | |
1374 | inside loop. We could handle this by counting the number into | |
1375 | temporary just like we do in runtime unrolling, but it does not | |
1376 | seem worthwhile. */ | |
1377 | free_simple_loop_desc (loop); | |
1378 | } | |
1379 | } | |
c263766c RH |
1380 | if (dump_file) |
1381 | fprintf (dump_file, ";; Peeling loop %d times\n", npeel); | |
a29c7ea6 ZD |
1382 | } |
1383 | ||
1384 | /* Decide whether to unroll LOOP stupidly and how much. */ | |
1385 | static void | |
d47cc544 | 1386 | decide_unroll_stupid (struct loop *loop, int flags) |
a29c7ea6 ZD |
1387 | { |
1388 | unsigned nunroll, nunroll_by_av, i; | |
50654f6c | 1389 | struct niter_desc *desc; |
e3a8f1fa | 1390 | double_int iterations; |
a29c7ea6 ZD |
1391 | |
1392 | if (!(flags & UAP_UNROLL_ALL)) | |
1393 | { | |
1394 | /* We were not asked to, just return back silently. */ | |
1395 | return; | |
1396 | } | |
1397 | ||
c263766c RH |
1398 | if (dump_file) |
1399 | fprintf (dump_file, "\n;; Considering unrolling loop stupidly\n"); | |
a29c7ea6 ZD |
1400 | |
1401 | /* nunroll = total number of copies of the original loop body in | |
1402 | unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */ | |
1403 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns; | |
c263766c RH |
1404 | nunroll_by_av |
1405 | = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns; | |
a29c7ea6 ZD |
1406 | if (nunroll > nunroll_by_av) |
1407 | nunroll = nunroll_by_av; | |
1408 | if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES)) | |
1409 | nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES); | |
1410 | ||
40ac4f73 CB |
1411 | if (targetm.loop_unroll_adjust) |
1412 | nunroll = targetm.loop_unroll_adjust (nunroll, loop); | |
1413 | ||
a29c7ea6 ZD |
1414 | /* Skip big loops. */ |
1415 | if (nunroll <= 1) | |
1416 | { | |
c263766c RH |
1417 | if (dump_file) |
1418 | fprintf (dump_file, ";; Not considering loop, is too big\n"); | |
a29c7ea6 ZD |
1419 | return; |
1420 | } | |
1421 | ||
1422 | /* Check for simple loops. */ | |
50654f6c | 1423 | desc = get_simple_loop_desc (loop); |
a29c7ea6 ZD |
1424 | |
1425 | /* Check simpleness. */ | |
50654f6c | 1426 | if (desc->simple_p && !desc->assumptions) |
a29c7ea6 | 1427 | { |
c263766c RH |
1428 | if (dump_file) |
1429 | fprintf (dump_file, ";; The loop is simple\n"); | |
a29c7ea6 ZD |
1430 | return; |
1431 | } | |
1432 | ||
1433 | /* Do not unroll loops with branches inside -- it increases number | |
6acf25e4 JH |
1434 | of mispredicts. |
1435 | TODO: this heuristic needs tunning; call inside the loop body | |
1436 | is also relatively good reason to not unroll. */ | |
50654f6c | 1437 | if (num_loop_branches (loop) > 1) |
a29c7ea6 | 1438 | { |
c263766c RH |
1439 | if (dump_file) |
1440 | fprintf (dump_file, ";; Not unrolling, contains branches\n"); | |
a29c7ea6 ZD |
1441 | return; |
1442 | } | |
1443 | ||
73367f92 | 1444 | /* Check whether the loop rolls. */ |
e3a8f1fa JH |
1445 | if ((estimated_loop_iterations (loop, &iterations) |
1446 | || max_loop_iterations (loop, &iterations)) | |
73367f92 | 1447 | && iterations.ult (double_int::from_shwi (2 * nunroll))) |
a29c7ea6 | 1448 | { |
c263766c RH |
1449 | if (dump_file) |
1450 | fprintf (dump_file, ";; Not unrolling loop, doesn't roll\n"); | |
a29c7ea6 ZD |
1451 | return; |
1452 | } | |
1453 | ||
1454 | /* Success. Now force nunroll to be power of 2, as it seems that this | |
e0bb17a8 | 1455 | improves results (partially because of better alignments, partially |
a29c7ea6 | 1456 | because of some dark magic). */ |
50654f6c ZD |
1457 | for (i = 1; 2 * i <= nunroll; i *= 2) |
1458 | continue; | |
a29c7ea6 ZD |
1459 | |
1460 | loop->lpt_decision.decision = LPT_UNROLL_STUPID; | |
1461 | loop->lpt_decision.times = i - 1; | |
b8698a0f | 1462 | |
c263766c | 1463 | if (dump_file) |
4fc2e37d | 1464 | fprintf (dump_file, ";; Decided to unroll the loop stupidly %d times.\n", |
50654f6c | 1465 | loop->lpt_decision.times); |
a29c7ea6 ZD |
1466 | } |
1467 | ||
4fc2e37d EB |
1468 | /* Unroll a LOOP LOOP->LPT_DECISION.TIMES times. The transformation does this: |
1469 | ||
a29c7ea6 ZD |
1470 | while (cond) |
1471 | body; | |
1472 | ||
4fc2e37d | 1473 | ==> (LOOP->LPT_DECISION.TIMES == 3) |
a29c7ea6 ZD |
1474 | |
1475 | while (cond) | |
1476 | { | |
1477 | body; | |
1478 | if (!cond) break; | |
1479 | body; | |
1480 | if (!cond) break; | |
1481 | body; | |
1482 | if (!cond) break; | |
1483 | body; | |
1484 | } | |
1485 | */ | |
1486 | static void | |
d73be268 | 1487 | unroll_loop_stupid (struct loop *loop) |
a29c7ea6 ZD |
1488 | { |
1489 | sbitmap wont_exit; | |
1490 | unsigned nunroll = loop->lpt_decision.times; | |
50654f6c | 1491 | struct niter_desc *desc = get_simple_loop_desc (loop); |
f37a4f14 | 1492 | struct opt_info *opt_info = NULL; |
41806d92 | 1493 | bool ok; |
b8698a0f | 1494 | |
f37a4f14 RE |
1495 | if (flag_split_ivs_in_unroller |
1496 | || flag_variable_expansion_in_unroller) | |
1497 | opt_info = analyze_insns_in_loop (loop); | |
b8698a0f L |
1498 | |
1499 | ||
a29c7ea6 | 1500 | wont_exit = sbitmap_alloc (nunroll + 1); |
f61e445a | 1501 | bitmap_clear (wont_exit); |
f37a4f14 | 1502 | opt_info_start_duplication (opt_info); |
b8698a0f | 1503 | |
41806d92 | 1504 | ok = duplicate_loop_to_header_edge (loop, loop_latch_edge (loop), |
d73be268 | 1505 | nunroll, wont_exit, |
ee8c1b05 | 1506 | NULL, NULL, |
7f7b1718 JH |
1507 | DLTHE_FLAG_UPDATE_FREQ |
1508 | | (opt_info | |
1509 | ? DLTHE_RECORD_COPY_NUMBER | |
1510 | : 0)); | |
41806d92 | 1511 | gcc_assert (ok); |
b8698a0f | 1512 | |
f37a4f14 | 1513 | if (opt_info) |
113d659a | 1514 | { |
f37a4f14 RE |
1515 | apply_opt_in_copies (opt_info, nunroll, true, true); |
1516 | free_opt_info (opt_info); | |
113d659a ZD |
1517 | } |
1518 | ||
a29c7ea6 | 1519 | free (wont_exit); |
0c20a65f | 1520 | |
50654f6c ZD |
1521 | if (desc->simple_p) |
1522 | { | |
1523 | /* We indeed may get here provided that there are nontrivial assumptions | |
1524 | for a loop to be really simple. We could update the counts, but the | |
1525 | problem is that we are unable to decide which exit will be taken | |
1526 | (not really true in case the number of iterations is constant, | |
1527 | but noone will do anything with this information, so we do not | |
1528 | worry about it). */ | |
1529 | desc->simple_p = false; | |
1530 | } | |
1531 | ||
c263766c RH |
1532 | if (dump_file) |
1533 | fprintf (dump_file, ";; Unrolled loop %d times, %i insns\n", | |
a29c7ea6 ZD |
1534 | nunroll, num_loop_insns (loop)); |
1535 | } | |
113d659a ZD |
1536 | |
1537 | /* A hash function for information about insns to split. */ | |
1538 | ||
1539 | static hashval_t | |
1540 | si_info_hash (const void *ivts) | |
1541 | { | |
741ac903 | 1542 | return (hashval_t) INSN_UID (((const struct iv_to_split *) ivts)->insn); |
113d659a ZD |
1543 | } |
1544 | ||
1545 | /* An equality functions for information about insns to split. */ | |
1546 | ||
1547 | static int | |
1548 | si_info_eq (const void *ivts1, const void *ivts2) | |
1549 | { | |
d3bfe4de KG |
1550 | const struct iv_to_split *const i1 = (const struct iv_to_split *) ivts1; |
1551 | const struct iv_to_split *const i2 = (const struct iv_to_split *) ivts2; | |
113d659a ZD |
1552 | |
1553 | return i1->insn == i2->insn; | |
1554 | } | |
1555 | ||
f37a4f14 RE |
1556 | /* Return a hash for VES, which is really a "var_to_expand *". */ |
1557 | ||
1558 | static hashval_t | |
1559 | ve_info_hash (const void *ves) | |
1560 | { | |
741ac903 | 1561 | return (hashval_t) INSN_UID (((const struct var_to_expand *) ves)->insn); |
f37a4f14 RE |
1562 | } |
1563 | ||
b8698a0f | 1564 | /* Return true if IVTS1 and IVTS2 (which are really both of type |
471854f8 | 1565 | "var_to_expand *") refer to the same instruction. */ |
f37a4f14 RE |
1566 | |
1567 | static int | |
1568 | ve_info_eq (const void *ivts1, const void *ivts2) | |
1569 | { | |
d3bfe4de KG |
1570 | const struct var_to_expand *const i1 = (const struct var_to_expand *) ivts1; |
1571 | const struct var_to_expand *const i2 = (const struct var_to_expand *) ivts2; | |
b8698a0f | 1572 | |
f37a4f14 RE |
1573 | return i1->insn == i2->insn; |
1574 | } | |
1575 | ||
60c48e4c AO |
1576 | /* Returns true if REG is referenced in one nondebug insn in LOOP. |
1577 | Set *DEBUG_USES to the number of debug insns that reference the | |
1578 | variable. */ | |
f37a4f14 RE |
1579 | |
1580 | bool | |
60c48e4c AO |
1581 | referenced_in_one_insn_in_loop_p (struct loop *loop, rtx reg, |
1582 | int *debug_uses) | |
f37a4f14 RE |
1583 | { |
1584 | basic_block *body, bb; | |
1585 | unsigned i; | |
1586 | int count_ref = 0; | |
1587 | rtx insn; | |
b8698a0f L |
1588 | |
1589 | body = get_loop_body (loop); | |
f37a4f14 RE |
1590 | for (i = 0; i < loop->num_nodes; i++) |
1591 | { | |
1592 | bb = body[i]; | |
b8698a0f | 1593 | |
f37a4f14 | 1594 | FOR_BB_INSNS (bb, insn) |
60c48e4c AO |
1595 | if (!rtx_referenced_p (reg, insn)) |
1596 | continue; | |
1597 | else if (DEBUG_INSN_P (insn)) | |
1598 | ++*debug_uses; | |
1599 | else if (++count_ref > 1) | |
1600 | break; | |
f37a4f14 | 1601 | } |
60c48e4c | 1602 | free (body); |
f37a4f14 RE |
1603 | return (count_ref == 1); |
1604 | } | |
1605 | ||
60c48e4c AO |
1606 | /* Reset the DEBUG_USES debug insns in LOOP that reference REG. */ |
1607 | ||
1608 | static void | |
1609 | reset_debug_uses_in_loop (struct loop *loop, rtx reg, int debug_uses) | |
1610 | { | |
1611 | basic_block *body, bb; | |
1612 | unsigned i; | |
1613 | rtx insn; | |
1614 | ||
1615 | body = get_loop_body (loop); | |
1616 | for (i = 0; debug_uses && i < loop->num_nodes; i++) | |
1617 | { | |
1618 | bb = body[i]; | |
1619 | ||
1620 | FOR_BB_INSNS (bb, insn) | |
1621 | if (!DEBUG_INSN_P (insn) || !rtx_referenced_p (reg, insn)) | |
1622 | continue; | |
1623 | else | |
1624 | { | |
1625 | validate_change (insn, &INSN_VAR_LOCATION_LOC (insn), | |
1626 | gen_rtx_UNKNOWN_VAR_LOC (), 0); | |
1627 | if (!--debug_uses) | |
1628 | break; | |
1629 | } | |
1630 | } | |
1631 | free (body); | |
1632 | } | |
1633 | ||
f37a4f14 | 1634 | /* Determine whether INSN contains an accumulator |
b8698a0f | 1635 | which can be expanded into separate copies, |
f37a4f14 | 1636 | one for each copy of the LOOP body. |
b8698a0f | 1637 | |
f37a4f14 RE |
1638 | for (i = 0 ; i < n; i++) |
1639 | sum += a[i]; | |
b8698a0f | 1640 | |
f37a4f14 | 1641 | ==> |
b8698a0f | 1642 | |
f37a4f14 RE |
1643 | sum += a[i] |
1644 | .... | |
1645 | i = i+1; | |
1646 | sum1 += a[i] | |
1647 | .... | |
1648 | i = i+1 | |
1649 | sum2 += a[i]; | |
1650 | .... | |
1651 | ||
b8698a0f L |
1652 | Return NULL if INSN contains no opportunity for expansion of accumulator. |
1653 | Otherwise, allocate a VAR_TO_EXPAND structure, fill it with the relevant | |
f37a4f14 RE |
1654 | information and return a pointer to it. |
1655 | */ | |
1656 | ||
1657 | static struct var_to_expand * | |
1658 | analyze_insn_to_expand_var (struct loop *loop, rtx insn) | |
1659 | { | |
531e5376 | 1660 | rtx set, dest, src; |
f37a4f14 | 1661 | struct var_to_expand *ves; |
76fd2caa | 1662 | unsigned accum_pos; |
531e5376 | 1663 | enum rtx_code code; |
60c48e4c | 1664 | int debug_uses = 0; |
76fd2caa | 1665 | |
f37a4f14 RE |
1666 | set = single_set (insn); |
1667 | if (!set) | |
1668 | return NULL; | |
b8698a0f | 1669 | |
f37a4f14 RE |
1670 | dest = SET_DEST (set); |
1671 | src = SET_SRC (set); | |
531e5376 | 1672 | code = GET_CODE (src); |
b8698a0f | 1673 | |
531e5376 | 1674 | if (code != PLUS && code != MINUS && code != MULT && code != FMA) |
f37a4f14 | 1675 | return NULL; |
f2dd440f | 1676 | |
531e5376 RH |
1677 | if (FLOAT_MODE_P (GET_MODE (dest))) |
1678 | { | |
1679 | if (!flag_associative_math) | |
1680 | return NULL; | |
1681 | /* In the case of FMA, we're also changing the rounding. */ | |
1682 | if (code == FMA && !flag_unsafe_math_optimizations) | |
1683 | return NULL; | |
1684 | } | |
1685 | ||
f2dd440f SB |
1686 | /* Hmm, this is a bit paradoxical. We know that INSN is a valid insn |
1687 | in MD. But if there is no optab to generate the insn, we can not | |
1688 | perform the variable expansion. This can happen if an MD provides | |
1689 | an insn but not a named pattern to generate it, for example to avoid | |
1690 | producing code that needs additional mode switches like for x87/mmx. | |
1691 | ||
1692 | So we check have_insn_for which looks for an optab for the operation | |
1693 | in SRC. If it doesn't exist, we can't perform the expansion even | |
1694 | though INSN is valid. */ | |
531e5376 | 1695 | if (!have_insn_for (code, GET_MODE (src))) |
f2dd440f SB |
1696 | return NULL; |
1697 | ||
f37a4f14 RE |
1698 | if (!REG_P (dest) |
1699 | && !(GET_CODE (dest) == SUBREG | |
1700 | && REG_P (SUBREG_REG (dest)))) | |
1701 | return NULL; | |
b8698a0f | 1702 | |
531e5376 RH |
1703 | /* Find the accumulator use within the operation. */ |
1704 | if (code == FMA) | |
1705 | { | |
1706 | /* We only support accumulation via FMA in the ADD position. */ | |
1707 | if (!rtx_equal_p (dest, XEXP (src, 2))) | |
1708 | return NULL; | |
1709 | accum_pos = 2; | |
1710 | } | |
1711 | else if (rtx_equal_p (dest, XEXP (src, 0))) | |
76fd2caa | 1712 | accum_pos = 0; |
531e5376 RH |
1713 | else if (rtx_equal_p (dest, XEXP (src, 1))) |
1714 | { | |
1715 | /* The method of expansion that we are using; which includes the | |
1716 | initialization of the expansions with zero and the summation of | |
1717 | the expansions at the end of the computation will yield wrong | |
1718 | results for (x = something - x) thus avoid using it in that case. */ | |
1719 | if (code == MINUS) | |
1720 | return NULL; | |
1721 | accum_pos = 1; | |
1722 | } | |
76fd2caa RE |
1723 | else |
1724 | return NULL; | |
1725 | ||
531e5376 RH |
1726 | /* It must not otherwise be used. */ |
1727 | if (code == FMA) | |
1728 | { | |
1729 | if (rtx_referenced_p (dest, XEXP (src, 0)) | |
1730 | || rtx_referenced_p (dest, XEXP (src, 1))) | |
1731 | return NULL; | |
1732 | } | |
1733 | else if (rtx_referenced_p (dest, XEXP (src, 1 - accum_pos))) | |
f37a4f14 | 1734 | return NULL; |
b8698a0f | 1735 | |
531e5376 | 1736 | /* It must be used in exactly one insn. */ |
60c48e4c | 1737 | if (!referenced_in_one_insn_in_loop_p (loop, dest, &debug_uses)) |
f37a4f14 | 1738 | return NULL; |
b8698a0f | 1739 | |
c1c5a431 | 1740 | if (dump_file) |
531e5376 RH |
1741 | { |
1742 | fprintf (dump_file, "\n;; Expanding Accumulator "); | |
1743 | print_rtl (dump_file, dest); | |
1744 | fprintf (dump_file, "\n"); | |
1745 | } | |
c1c5a431 | 1746 | |
60c48e4c AO |
1747 | if (debug_uses) |
1748 | /* Instead of resetting the debug insns, we could replace each | |
1749 | debug use in the loop with the sum or product of all expanded | |
1750 | accummulators. Since we'll only know of all expansions at the | |
1751 | end, we'd have to keep track of which vars_to_expand a debug | |
1752 | insn in the loop references, take note of each copy of the | |
1753 | debug insn during unrolling, and when it's all done, compute | |
1754 | the sum or product of each variable and adjust the original | |
1755 | debug insn and each copy thereof. What a pain! */ | |
1756 | reset_debug_uses_in_loop (loop, dest, debug_uses); | |
1757 | ||
f37a4f14 | 1758 | /* Record the accumulator to expand. */ |
5ed6ace5 | 1759 | ves = XNEW (struct var_to_expand); |
f37a4f14 | 1760 | ves->insn = insn; |
f37a4f14 | 1761 | ves->reg = copy_rtx (dest); |
a9f6ecee AO |
1762 | ves->var_expansions = VEC_alloc (rtx, heap, 1); |
1763 | ves->next = NULL; | |
f37a4f14 RE |
1764 | ves->op = GET_CODE (src); |
1765 | ves->expansion_count = 0; | |
1766 | ves->reuse_expansion = 0; | |
b8698a0f | 1767 | return ves; |
f37a4f14 RE |
1768 | } |
1769 | ||
113d659a | 1770 | /* Determine whether there is an induction variable in INSN that |
b8698a0f | 1771 | we would like to split during unrolling. |
f37a4f14 RE |
1772 | |
1773 | I.e. replace | |
1774 | ||
1775 | i = i + 1; | |
1776 | ... | |
1777 | i = i + 1; | |
1778 | ... | |
1779 | i = i + 1; | |
1780 | ... | |
1781 | ||
1782 | type chains by | |
1783 | ||
1784 | i0 = i + 1 | |
1785 | ... | |
1786 | i = i0 + 1 | |
1787 | ... | |
1788 | i = i0 + 2 | |
1789 | ... | |
1790 | ||
b8698a0f | 1791 | Return NULL if INSN contains no interesting IVs. Otherwise, allocate |
f37a4f14 | 1792 | an IV_TO_SPLIT structure, fill it with the relevant information and return a |
113d659a ZD |
1793 | pointer to it. */ |
1794 | ||
1795 | static struct iv_to_split * | |
1796 | analyze_iv_to_split_insn (rtx insn) | |
1797 | { | |
1798 | rtx set, dest; | |
1799 | struct rtx_iv iv; | |
1800 | struct iv_to_split *ivts; | |
41806d92 | 1801 | bool ok; |
113d659a ZD |
1802 | |
1803 | /* For now we just split the basic induction variables. Later this may be | |
1804 | extended for example by selecting also addresses of memory references. */ | |
1805 | set = single_set (insn); | |
1806 | if (!set) | |
1807 | return NULL; | |
1808 | ||
1809 | dest = SET_DEST (set); | |
1810 | if (!REG_P (dest)) | |
1811 | return NULL; | |
1812 | ||
1813 | if (!biv_p (insn, dest)) | |
1814 | return NULL; | |
1815 | ||
03fd2215 | 1816 | ok = iv_analyze_result (insn, dest, &iv); |
4dc7782d JL |
1817 | |
1818 | /* This used to be an assert under the assumption that if biv_p returns | |
1819 | true that iv_analyze_result must also return true. However, that | |
1820 | assumption is not strictly correct as evidenced by pr25569. | |
1821 | ||
1822 | Returning NULL when iv_analyze_result returns false is safe and | |
1823 | avoids the problems in pr25569 until the iv_analyze_* routines | |
1824 | can be fixed, which is apparently hard and time consuming | |
1825 | according to their author. */ | |
1826 | if (! ok) | |
1827 | return NULL; | |
113d659a ZD |
1828 | |
1829 | if (iv.step == const0_rtx | |
1830 | || iv.mode != iv.extend_mode) | |
1831 | return NULL; | |
1832 | ||
1833 | /* Record the insn to split. */ | |
5ed6ace5 | 1834 | ivts = XNEW (struct iv_to_split); |
113d659a ZD |
1835 | ivts->insn = insn; |
1836 | ivts->base_var = NULL_RTX; | |
1837 | ivts->step = iv.step; | |
a9f6ecee | 1838 | ivts->next = NULL; |
113d659a ZD |
1839 | ivts->n_loc = 1; |
1840 | ivts->loc[0] = 1; | |
b8698a0f | 1841 | |
113d659a ZD |
1842 | return ivts; |
1843 | } | |
1844 | ||
f37a4f14 RE |
1845 | /* Determines which of insns in LOOP can be optimized. |
1846 | Return a OPT_INFO struct with the relevant hash tables filled | |
1847 | with all insns to be optimized. The FIRST_NEW_BLOCK field | |
113d659a ZD |
1848 | is undefined for the return value. */ |
1849 | ||
f37a4f14 RE |
1850 | static struct opt_info * |
1851 | analyze_insns_in_loop (struct loop *loop) | |
113d659a ZD |
1852 | { |
1853 | basic_block *body, bb; | |
ca83d385 | 1854 | unsigned i; |
5ed6ace5 | 1855 | struct opt_info *opt_info = XCNEW (struct opt_info); |
113d659a | 1856 | rtx insn; |
f37a4f14 RE |
1857 | struct iv_to_split *ivts = NULL; |
1858 | struct var_to_expand *ves = NULL; | |
1859 | PTR *slot1; | |
1860 | PTR *slot2; | |
ca83d385 ZD |
1861 | VEC (edge, heap) *edges = get_loop_exit_edges (loop); |
1862 | edge exit; | |
f37a4f14 | 1863 | bool can_apply = false; |
b8698a0f | 1864 | |
113d659a ZD |
1865 | iv_analysis_loop_init (loop); |
1866 | ||
1867 | body = get_loop_body (loop); | |
f37a4f14 RE |
1868 | |
1869 | if (flag_split_ivs_in_unroller) | |
a9f6ecee AO |
1870 | { |
1871 | opt_info->insns_to_split = htab_create (5 * loop->num_nodes, | |
1872 | si_info_hash, si_info_eq, free); | |
1873 | opt_info->iv_to_split_head = NULL; | |
1874 | opt_info->iv_to_split_tail = &opt_info->iv_to_split_head; | |
1875 | } | |
b8698a0f | 1876 | |
f37a4f14 | 1877 | /* Record the loop exit bb and loop preheader before the unrolling. */ |
598ec7bd | 1878 | opt_info->loop_preheader = loop_preheader_edge (loop)->src; |
b8698a0f | 1879 | |
ca83d385 | 1880 | if (VEC_length (edge, edges) == 1) |
f37a4f14 | 1881 | { |
ca83d385 ZD |
1882 | exit = VEC_index (edge, edges, 0); |
1883 | if (!(exit->flags & EDGE_COMPLEX)) | |
1884 | { | |
1885 | opt_info->loop_exit = split_edge (exit); | |
1886 | can_apply = true; | |
1887 | } | |
f37a4f14 | 1888 | } |
b8698a0f | 1889 | |
f37a4f14 RE |
1890 | if (flag_variable_expansion_in_unroller |
1891 | && can_apply) | |
a9f6ecee AO |
1892 | { |
1893 | opt_info->insns_with_var_to_expand = htab_create (5 * loop->num_nodes, | |
1894 | ve_info_hash, | |
1895 | ve_info_eq, free); | |
1896 | opt_info->var_to_expand_head = NULL; | |
1897 | opt_info->var_to_expand_tail = &opt_info->var_to_expand_head; | |
1898 | } | |
b8698a0f | 1899 | |
113d659a ZD |
1900 | for (i = 0; i < loop->num_nodes; i++) |
1901 | { | |
1902 | bb = body[i]; | |
1903 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
1904 | continue; | |
1905 | ||
1906 | FOR_BB_INSNS (bb, insn) | |
f37a4f14 RE |
1907 | { |
1908 | if (!INSN_P (insn)) | |
1909 | continue; | |
b8698a0f | 1910 | |
f37a4f14 RE |
1911 | if (opt_info->insns_to_split) |
1912 | ivts = analyze_iv_to_split_insn (insn); | |
b8698a0f | 1913 | |
f37a4f14 RE |
1914 | if (ivts) |
1915 | { | |
1916 | slot1 = htab_find_slot (opt_info->insns_to_split, ivts, INSERT); | |
a9f6ecee | 1917 | gcc_assert (*slot1 == NULL); |
f37a4f14 | 1918 | *slot1 = ivts; |
a9f6ecee AO |
1919 | *opt_info->iv_to_split_tail = ivts; |
1920 | opt_info->iv_to_split_tail = &ivts->next; | |
f37a4f14 RE |
1921 | continue; |
1922 | } | |
b8698a0f | 1923 | |
f37a4f14 RE |
1924 | if (opt_info->insns_with_var_to_expand) |
1925 | ves = analyze_insn_to_expand_var (loop, insn); | |
b8698a0f | 1926 | |
f37a4f14 RE |
1927 | if (ves) |
1928 | { | |
1929 | slot2 = htab_find_slot (opt_info->insns_with_var_to_expand, ves, INSERT); | |
a9f6ecee | 1930 | gcc_assert (*slot2 == NULL); |
f37a4f14 | 1931 | *slot2 = ves; |
a9f6ecee AO |
1932 | *opt_info->var_to_expand_tail = ves; |
1933 | opt_info->var_to_expand_tail = &ves->next; | |
f37a4f14 RE |
1934 | } |
1935 | } | |
113d659a | 1936 | } |
b8698a0f | 1937 | |
ca83d385 | 1938 | VEC_free (edge, heap, edges); |
113d659a | 1939 | free (body); |
f37a4f14 | 1940 | return opt_info; |
113d659a ZD |
1941 | } |
1942 | ||
1943 | /* Called just before loop duplication. Records start of duplicated area | |
f37a4f14 | 1944 | to OPT_INFO. */ |
113d659a | 1945 | |
b8698a0f | 1946 | static void |
f37a4f14 | 1947 | opt_info_start_duplication (struct opt_info *opt_info) |
113d659a | 1948 | { |
f37a4f14 RE |
1949 | if (opt_info) |
1950 | opt_info->first_new_block = last_basic_block; | |
113d659a ZD |
1951 | } |
1952 | ||
1953 | /* Determine the number of iterations between initialization of the base | |
1954 | variable and the current copy (N_COPY). N_COPIES is the total number | |
1955 | of newly created copies. UNROLLING is true if we are unrolling | |
1956 | (not peeling) the loop. */ | |
1957 | ||
1958 | static unsigned | |
1959 | determine_split_iv_delta (unsigned n_copy, unsigned n_copies, bool unrolling) | |
1960 | { | |
1961 | if (unrolling) | |
1962 | { | |
1963 | /* If we are unrolling, initialization is done in the original loop | |
1964 | body (number 0). */ | |
1965 | return n_copy; | |
1966 | } | |
1967 | else | |
1968 | { | |
1969 | /* If we are peeling, the copy in that the initialization occurs has | |
1970 | number 1. The original loop (number 0) is the last. */ | |
1971 | if (n_copy) | |
1972 | return n_copy - 1; | |
1973 | else | |
1974 | return n_copies; | |
1975 | } | |
1976 | } | |
1977 | ||
1978 | /* Locate in EXPR the expression corresponding to the location recorded | |
1979 | in IVTS, and return a pointer to the RTX for this location. */ | |
1980 | ||
1981 | static rtx * | |
1982 | get_ivts_expr (rtx expr, struct iv_to_split *ivts) | |
1983 | { | |
1984 | unsigned i; | |
1985 | rtx *ret = &expr; | |
1986 | ||
1987 | for (i = 0; i < ivts->n_loc; i++) | |
1988 | ret = &XEXP (*ret, ivts->loc[i]); | |
1989 | ||
1990 | return ret; | |
1991 | } | |
1992 | ||
a9f6ecee | 1993 | /* Allocate basic variable for the induction variable chain. */ |
113d659a | 1994 | |
a9f6ecee AO |
1995 | static void |
1996 | allocate_basic_variable (struct iv_to_split *ivts) | |
113d659a | 1997 | { |
113d659a ZD |
1998 | rtx expr = *get_ivts_expr (single_set (ivts->insn), ivts); |
1999 | ||
2000 | ivts->base_var = gen_reg_rtx (GET_MODE (expr)); | |
113d659a ZD |
2001 | } |
2002 | ||
2003 | /* Insert initialization of basic variable of IVTS before INSN, taking | |
2004 | the initial value from INSN. */ | |
2005 | ||
2006 | static void | |
2007 | insert_base_initialization (struct iv_to_split *ivts, rtx insn) | |
2008 | { | |
2009 | rtx expr = copy_rtx (*get_ivts_expr (single_set (insn), ivts)); | |
2010 | rtx seq; | |
2011 | ||
2012 | start_sequence (); | |
2013 | expr = force_operand (expr, ivts->base_var); | |
2014 | if (expr != ivts->base_var) | |
2015 | emit_move_insn (ivts->base_var, expr); | |
2016 | seq = get_insns (); | |
2017 | end_sequence (); | |
2018 | ||
2019 | emit_insn_before (seq, insn); | |
2020 | } | |
2021 | ||
2022 | /* Replace the use of induction variable described in IVTS in INSN | |
2023 | by base variable + DELTA * step. */ | |
2024 | ||
2025 | static void | |
2026 | split_iv (struct iv_to_split *ivts, rtx insn, unsigned delta) | |
2027 | { | |
2028 | rtx expr, *loc, seq, incr, var; | |
2029 | enum machine_mode mode = GET_MODE (ivts->base_var); | |
2030 | rtx src, dest, set; | |
2031 | ||
2032 | /* Construct base + DELTA * step. */ | |
2033 | if (!delta) | |
2034 | expr = ivts->base_var; | |
2035 | else | |
2036 | { | |
2037 | incr = simplify_gen_binary (MULT, mode, | |
2038 | ivts->step, gen_int_mode (delta, mode)); | |
2039 | expr = simplify_gen_binary (PLUS, GET_MODE (ivts->base_var), | |
2040 | ivts->base_var, incr); | |
2041 | } | |
2042 | ||
2043 | /* Figure out where to do the replacement. */ | |
2044 | loc = get_ivts_expr (single_set (insn), ivts); | |
2045 | ||
2046 | /* If we can make the replacement right away, we're done. */ | |
2047 | if (validate_change (insn, loc, expr, 0)) | |
2048 | return; | |
2049 | ||
2050 | /* Otherwise, force EXPR into a register and try again. */ | |
2051 | start_sequence (); | |
2052 | var = gen_reg_rtx (mode); | |
2053 | expr = force_operand (expr, var); | |
2054 | if (expr != var) | |
2055 | emit_move_insn (var, expr); | |
2056 | seq = get_insns (); | |
2057 | end_sequence (); | |
2058 | emit_insn_before (seq, insn); | |
b8698a0f | 2059 | |
113d659a ZD |
2060 | if (validate_change (insn, loc, var, 0)) |
2061 | return; | |
2062 | ||
2063 | /* The last chance. Try recreating the assignment in insn | |
2064 | completely from scratch. */ | |
2065 | set = single_set (insn); | |
2066 | gcc_assert (set); | |
2067 | ||
2068 | start_sequence (); | |
2069 | *loc = var; | |
2070 | src = copy_rtx (SET_SRC (set)); | |
2071 | dest = copy_rtx (SET_DEST (set)); | |
2072 | src = force_operand (src, dest); | |
2073 | if (src != dest) | |
2074 | emit_move_insn (dest, src); | |
2075 | seq = get_insns (); | |
2076 | end_sequence (); | |
b8698a0f | 2077 | |
113d659a ZD |
2078 | emit_insn_before (seq, insn); |
2079 | delete_insn (insn); | |
2080 | } | |
2081 | ||
113d659a | 2082 | |
2cd0e9f4 | 2083 | /* Return one expansion of the accumulator recorded in struct VE. */ |
113d659a | 2084 | |
f37a4f14 RE |
2085 | static rtx |
2086 | get_expansion (struct var_to_expand *ve) | |
2087 | { | |
2088 | rtx reg; | |
b8698a0f | 2089 | |
f37a4f14 RE |
2090 | if (ve->reuse_expansion == 0) |
2091 | reg = ve->reg; | |
2092 | else | |
0cc39082 | 2093 | reg = VEC_index (rtx, ve->var_expansions, ve->reuse_expansion - 1); |
b8698a0f | 2094 | |
0cc39082 | 2095 | if (VEC_length (rtx, ve->var_expansions) == (unsigned) ve->reuse_expansion) |
f37a4f14 | 2096 | ve->reuse_expansion = 0; |
b8698a0f | 2097 | else |
f37a4f14 | 2098 | ve->reuse_expansion++; |
b8698a0f | 2099 | |
f37a4f14 RE |
2100 | return reg; |
2101 | } | |
113d659a | 2102 | |
113d659a | 2103 | |
b8698a0f | 2104 | /* Given INSN replace the uses of the accumulator recorded in VE |
f37a4f14 RE |
2105 | with a new register. */ |
2106 | ||
2107 | static void | |
2108 | expand_var_during_unrolling (struct var_to_expand *ve, rtx insn) | |
2109 | { | |
2110 | rtx new_reg, set; | |
2111 | bool really_new_expansion = false; | |
b8698a0f | 2112 | |
f37a4f14 | 2113 | set = single_set (insn); |
b5e624c6 | 2114 | gcc_assert (set); |
b8698a0f | 2115 | |
f37a4f14 RE |
2116 | /* Generate a new register only if the expansion limit has not been |
2117 | reached. Else reuse an already existing expansion. */ | |
2118 | if (PARAM_VALUE (PARAM_MAX_VARIABLE_EXPANSIONS) > ve->expansion_count) | |
2119 | { | |
2120 | really_new_expansion = true; | |
2121 | new_reg = gen_reg_rtx (GET_MODE (ve->reg)); | |
2122 | } | |
2123 | else | |
2124 | new_reg = get_expansion (ve); | |
2125 | ||
6e74642b | 2126 | validate_replace_rtx_group (SET_DEST (set), new_reg, insn); |
f37a4f14 RE |
2127 | if (apply_change_group ()) |
2128 | if (really_new_expansion) | |
2129 | { | |
0cc39082 | 2130 | VEC_safe_push (rtx, heap, ve->var_expansions, new_reg); |
f37a4f14 RE |
2131 | ve->expansion_count++; |
2132 | } | |
2133 | } | |
2134 | ||
a9f6ecee AO |
2135 | /* Initialize the variable expansions in loop preheader. PLACE is the |
2136 | loop-preheader basic block where the initialization of the | |
2137 | expansions should take place. The expansions are initialized with | |
2138 | (-0) when the operation is plus or minus to honor sign zero. This | |
2139 | way we can prevent cases where the sign of the final result is | |
2140 | effected by the sign of the expansion. Here is an example to | |
2141 | demonstrate this: | |
b8698a0f | 2142 | |
290358f7 RE |
2143 | for (i = 0 ; i < n; i++) |
2144 | sum += something; | |
2145 | ||
2146 | ==> | |
2147 | ||
2148 | sum += something | |
2149 | .... | |
2150 | i = i+1; | |
2151 | sum1 += something | |
2152 | .... | |
2153 | i = i+1 | |
2154 | sum2 += something; | |
2155 | .... | |
b8698a0f | 2156 | |
290358f7 RE |
2157 | When SUM is initialized with -zero and SOMETHING is also -zero; the |
2158 | final result of sum should be -zero thus the expansions sum1 and sum2 | |
2159 | should be initialized with -zero as well (otherwise we will get +zero | |
2160 | as the final result). */ | |
f37a4f14 | 2161 | |
a9f6ecee AO |
2162 | static void |
2163 | insert_var_expansion_initialization (struct var_to_expand *ve, | |
2164 | basic_block place) | |
f37a4f14 | 2165 | { |
6e74642b | 2166 | rtx seq, var, zero_init; |
f37a4f14 | 2167 | unsigned i; |
290358f7 RE |
2168 | enum machine_mode mode = GET_MODE (ve->reg); |
2169 | bool honor_signed_zero_p = HONOR_SIGNED_ZEROS (mode); | |
2170 | ||
0cc39082 | 2171 | if (VEC_length (rtx, ve->var_expansions) == 0) |
a9f6ecee | 2172 | return; |
b8698a0f | 2173 | |
f37a4f14 | 2174 | start_sequence (); |
531e5376 RH |
2175 | switch (ve->op) |
2176 | { | |
2177 | case FMA: | |
2178 | /* Note that we only accumulate FMA via the ADD operand. */ | |
2179 | case PLUS: | |
2180 | case MINUS: | |
2181 | FOR_EACH_VEC_ELT (rtx, ve->var_expansions, i, var) | |
2182 | { | |
2183 | if (honor_signed_zero_p) | |
2184 | zero_init = simplify_gen_unary (NEG, mode, CONST0_RTX (mode), mode); | |
2185 | else | |
2186 | zero_init = CONST0_RTX (mode); | |
2187 | emit_move_insn (var, zero_init); | |
2188 | } | |
2189 | break; | |
2190 | ||
2191 | case MULT: | |
2192 | FOR_EACH_VEC_ELT (rtx, ve->var_expansions, i, var) | |
2193 | { | |
2194 | zero_init = CONST1_RTX (GET_MODE (var)); | |
2195 | emit_move_insn (var, zero_init); | |
2196 | } | |
2197 | break; | |
2198 | ||
2199 | default: | |
2200 | gcc_unreachable (); | |
2201 | } | |
b8698a0f | 2202 | |
f37a4f14 RE |
2203 | seq = get_insns (); |
2204 | end_sequence (); | |
b8698a0f | 2205 | |
6e74642b | 2206 | emit_insn_after (seq, BB_END (place)); |
f37a4f14 RE |
2207 | } |
2208 | ||
a9f6ecee AO |
2209 | /* Combine the variable expansions at the loop exit. PLACE is the |
2210 | loop exit basic block where the summation of the expansions should | |
2211 | take place. */ | |
f37a4f14 | 2212 | |
a9f6ecee AO |
2213 | static void |
2214 | combine_var_copies_in_loop_exit (struct var_to_expand *ve, basic_block place) | |
f37a4f14 | 2215 | { |
f37a4f14 RE |
2216 | rtx sum = ve->reg; |
2217 | rtx expr, seq, var, insn; | |
2218 | unsigned i; | |
2219 | ||
0cc39082 | 2220 | if (VEC_length (rtx, ve->var_expansions) == 0) |
a9f6ecee | 2221 | return; |
b8698a0f | 2222 | |
f37a4f14 | 2223 | start_sequence (); |
531e5376 RH |
2224 | switch (ve->op) |
2225 | { | |
2226 | case FMA: | |
2227 | /* Note that we only accumulate FMA via the ADD operand. */ | |
2228 | case PLUS: | |
2229 | case MINUS: | |
2230 | FOR_EACH_VEC_ELT (rtx, ve->var_expansions, i, var) | |
2231 | sum = simplify_gen_binary (PLUS, GET_MODE (ve->reg), var, sum); | |
2232 | break; | |
2233 | ||
2234 | case MULT: | |
2235 | FOR_EACH_VEC_ELT (rtx, ve->var_expansions, i, var) | |
2236 | sum = simplify_gen_binary (MULT, GET_MODE (ve->reg), var, sum); | |
2237 | break; | |
2238 | ||
2239 | default: | |
2240 | gcc_unreachable (); | |
2241 | } | |
b8698a0f | 2242 | |
f37a4f14 RE |
2243 | expr = force_operand (sum, ve->reg); |
2244 | if (expr != ve->reg) | |
2245 | emit_move_insn (ve->reg, expr); | |
2246 | seq = get_insns (); | |
2247 | end_sequence (); | |
b8698a0f | 2248 | |
f37a4f14 RE |
2249 | insn = BB_HEAD (place); |
2250 | while (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
2251 | insn = NEXT_INSN (insn); | |
2252 | ||
2253 | emit_insn_after (seq, insn); | |
f37a4f14 RE |
2254 | } |
2255 | ||
b8698a0f L |
2256 | /* Apply loop optimizations in loop copies using the |
2257 | data which gathered during the unrolling. Structure | |
f37a4f14 | 2258 | OPT_INFO record that data. |
b8698a0f | 2259 | |
113d659a ZD |
2260 | UNROLLING is true if we unrolled (not peeled) the loop. |
2261 | REWRITE_ORIGINAL_BODY is true if we should also rewrite the original body of | |
2262 | the loop (as it should happen in complete unrolling, but not in ordinary | |
2263 | peeling of the loop). */ | |
2264 | ||
2265 | static void | |
b8698a0f L |
2266 | apply_opt_in_copies (struct opt_info *opt_info, |
2267 | unsigned n_copies, bool unrolling, | |
f37a4f14 | 2268 | bool rewrite_original_loop) |
113d659a ZD |
2269 | { |
2270 | unsigned i, delta; | |
2271 | basic_block bb, orig_bb; | |
2272 | rtx insn, orig_insn, next; | |
2273 | struct iv_to_split ivts_templ, *ivts; | |
f37a4f14 | 2274 | struct var_to_expand ve_templ, *ves; |
b8698a0f | 2275 | |
113d659a ZD |
2276 | /* Sanity check -- we need to put initialization in the original loop |
2277 | body. */ | |
2278 | gcc_assert (!unrolling || rewrite_original_loop); | |
b8698a0f | 2279 | |
113d659a | 2280 | /* Allocate the basic variables (i0). */ |
f37a4f14 | 2281 | if (opt_info->insns_to_split) |
a9f6ecee AO |
2282 | for (ivts = opt_info->iv_to_split_head; ivts; ivts = ivts->next) |
2283 | allocate_basic_variable (ivts); | |
b8698a0f | 2284 | |
f37a4f14 | 2285 | for (i = opt_info->first_new_block; i < (unsigned) last_basic_block; i++) |
113d659a ZD |
2286 | { |
2287 | bb = BASIC_BLOCK (i); | |
6580ee77 | 2288 | orig_bb = get_bb_original (bb); |
b8698a0f | 2289 | |
6580ee77 JH |
2290 | /* bb->aux holds position in copy sequence initialized by |
2291 | duplicate_loop_to_header_edge. */ | |
2292 | delta = determine_split_iv_delta ((size_t)bb->aux, n_copies, | |
113d659a | 2293 | unrolling); |
7f7b1718 | 2294 | bb->aux = 0; |
113d659a ZD |
2295 | orig_insn = BB_HEAD (orig_bb); |
2296 | for (insn = BB_HEAD (bb); insn != NEXT_INSN (BB_END (bb)); insn = next) | |
f37a4f14 RE |
2297 | { |
2298 | next = NEXT_INSN (insn); | |
0397b965 JJ |
2299 | if (!INSN_P (insn) |
2300 | || (DEBUG_INSN_P (insn) | |
2301 | && TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL)) | |
f37a4f14 | 2302 | continue; |
b8698a0f | 2303 | |
0397b965 JJ |
2304 | while (!INSN_P (orig_insn) |
2305 | || (DEBUG_INSN_P (orig_insn) | |
2306 | && (TREE_CODE (INSN_VAR_LOCATION_DECL (orig_insn)) | |
2307 | == LABEL_DECL))) | |
f37a4f14 | 2308 | orig_insn = NEXT_INSN (orig_insn); |
b8698a0f | 2309 | |
f37a4f14 RE |
2310 | ivts_templ.insn = orig_insn; |
2311 | ve_templ.insn = orig_insn; | |
b8698a0f | 2312 | |
f37a4f14 RE |
2313 | /* Apply splitting iv optimization. */ |
2314 | if (opt_info->insns_to_split) | |
2315 | { | |
d3bfe4de KG |
2316 | ivts = (struct iv_to_split *) |
2317 | htab_find (opt_info->insns_to_split, &ivts_templ); | |
b8698a0f | 2318 | |
f37a4f14 RE |
2319 | if (ivts) |
2320 | { | |
21f868a2 ZD |
2321 | gcc_assert (GET_CODE (PATTERN (insn)) |
2322 | == GET_CODE (PATTERN (orig_insn))); | |
b8698a0f | 2323 | |
f37a4f14 RE |
2324 | if (!delta) |
2325 | insert_base_initialization (ivts, insn); | |
2326 | split_iv (ivts, insn, delta); | |
2327 | } | |
2328 | } | |
2329 | /* Apply variable expansion optimization. */ | |
2330 | if (unrolling && opt_info->insns_with_var_to_expand) | |
2331 | { | |
d3bfe4de KG |
2332 | ves = (struct var_to_expand *) |
2333 | htab_find (opt_info->insns_with_var_to_expand, &ve_templ); | |
f37a4f14 | 2334 | if (ves) |
b8698a0f | 2335 | { |
21f868a2 ZD |
2336 | gcc_assert (GET_CODE (PATTERN (insn)) |
2337 | == GET_CODE (PATTERN (orig_insn))); | |
f37a4f14 RE |
2338 | expand_var_during_unrolling (ves, insn); |
2339 | } | |
2340 | } | |
2341 | orig_insn = NEXT_INSN (orig_insn); | |
2342 | } | |
113d659a ZD |
2343 | } |
2344 | ||
2345 | if (!rewrite_original_loop) | |
2346 | return; | |
b8698a0f | 2347 | |
f37a4f14 | 2348 | /* Initialize the variable expansions in the loop preheader |
b8698a0f | 2349 | and take care of combining them at the loop exit. */ |
f37a4f14 RE |
2350 | if (opt_info->insns_with_var_to_expand) |
2351 | { | |
a9f6ecee AO |
2352 | for (ves = opt_info->var_to_expand_head; ves; ves = ves->next) |
2353 | insert_var_expansion_initialization (ves, opt_info->loop_preheader); | |
2354 | for (ves = opt_info->var_to_expand_head; ves; ves = ves->next) | |
2355 | combine_var_copies_in_loop_exit (ves, opt_info->loop_exit); | |
f37a4f14 | 2356 | } |
b8698a0f | 2357 | |
113d659a ZD |
2358 | /* Rewrite also the original loop body. Find them as originals of the blocks |
2359 | in the last copied iteration, i.e. those that have | |
6580ee77 | 2360 | get_bb_copy (get_bb_original (bb)) == bb. */ |
f37a4f14 | 2361 | for (i = opt_info->first_new_block; i < (unsigned) last_basic_block; i++) |
113d659a ZD |
2362 | { |
2363 | bb = BASIC_BLOCK (i); | |
6580ee77 JH |
2364 | orig_bb = get_bb_original (bb); |
2365 | if (get_bb_copy (orig_bb) != bb) | |
113d659a | 2366 | continue; |
b8698a0f | 2367 | |
113d659a ZD |
2368 | delta = determine_split_iv_delta (0, n_copies, unrolling); |
2369 | for (orig_insn = BB_HEAD (orig_bb); | |
f37a4f14 RE |
2370 | orig_insn != NEXT_INSN (BB_END (bb)); |
2371 | orig_insn = next) | |
2372 | { | |
2373 | next = NEXT_INSN (orig_insn); | |
b8698a0f | 2374 | |
f37a4f14 RE |
2375 | if (!INSN_P (orig_insn)) |
2376 | continue; | |
b8698a0f | 2377 | |
f37a4f14 RE |
2378 | ivts_templ.insn = orig_insn; |
2379 | if (opt_info->insns_to_split) | |
2380 | { | |
d3bfe4de KG |
2381 | ivts = (struct iv_to_split *) |
2382 | htab_find (opt_info->insns_to_split, &ivts_templ); | |
f37a4f14 RE |
2383 | if (ivts) |
2384 | { | |
2385 | if (!delta) | |
2386 | insert_base_initialization (ivts, orig_insn); | |
2387 | split_iv (ivts, orig_insn, delta); | |
2388 | continue; | |
2389 | } | |
2390 | } | |
b8698a0f | 2391 | |
f37a4f14 RE |
2392 | } |
2393 | } | |
2394 | } | |
113d659a | 2395 | |
f37a4f14 | 2396 | /* Release OPT_INFO. */ |
113d659a ZD |
2397 | |
2398 | static void | |
f37a4f14 | 2399 | free_opt_info (struct opt_info *opt_info) |
113d659a | 2400 | { |
f37a4f14 RE |
2401 | if (opt_info->insns_to_split) |
2402 | htab_delete (opt_info->insns_to_split); | |
2403 | if (opt_info->insns_with_var_to_expand) | |
2404 | { | |
a9f6ecee AO |
2405 | struct var_to_expand *ves; |
2406 | ||
2407 | for (ves = opt_info->var_to_expand_head; ves; ves = ves->next) | |
2408 | VEC_free (rtx, heap, ves->var_expansions); | |
f37a4f14 RE |
2409 | htab_delete (opt_info->insns_with_var_to_expand); |
2410 | } | |
2411 | free (opt_info); | |
113d659a | 2412 | } |