1 | /* Tail merging for gimple. |
2 | Copyright (C) 2011-2017 Free Software Foundation, Inc. |
3 | Contributed by Tom de Vries (tom@codesourcery.com) |
4 | |
5 | This file is part of GCC. |
6 | |
7 | GCC is free software; you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by |
9 | the Free Software Foundation; either version 3, or (at your option) |
10 | any later version. |
11 | |
12 | GCC is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
15 | GNU General Public License for more details. |
16 | |
17 | You should have received a copy of the GNU General Public License |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ |
20 | |
21 | /* Pass overview. |
22 | |
23 | |
24 | MOTIVATIONAL EXAMPLE |
25 | |
26 | gimple representation of gcc/testsuite/gcc.dg/pr43864.c at |
27 | |
28 | hprofStartupp (charD.1 * outputFileNameD.2600, charD.1 * ctxD.2601) |
29 | { |
30 | struct FILED.1638 * fpD.2605; |
31 | charD.1 fileNameD.2604[1000]; |
32 | intD.0 D.3915; |
33 | const charD.1 * restrict outputFileName.0D.3914; |
34 | |
35 | # BLOCK 2 freq:10000 |
36 | # PRED: ENTRY [100.0%] (fallthru,exec) |
37 | # PT = nonlocal { D.3926 } (restr) |
38 | outputFileName.0D.3914_3 |
39 | = (const charD.1 * restrict) outputFileNameD.2600_2(D); |
40 | # .MEMD.3923_13 = VDEF <.MEMD.3923_12(D)> |
41 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
42 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
43 | sprintfD.759 (&fileNameD.2604, outputFileName.0D.3914_3); |
44 | # .MEMD.3923_14 = VDEF <.MEMD.3923_13> |
45 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
46 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
47 | D.3915_4 = accessD.2606 (&fileNameD.2604, 1); |
48 | if (D.3915_4 == 0) |
49 | goto <bb 3>; |
50 | else |
51 | goto <bb 4>; |
52 | # SUCC: 3 [10.0%] (true,exec) 4 [90.0%] (false,exec) |
53 | |
54 | # BLOCK 3 freq:1000 |
55 | # PRED: 2 [10.0%] (true,exec) |
56 | # .MEMD.3923_15 = VDEF <.MEMD.3923_14> |
57 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
58 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
59 | freeD.898 (ctxD.2601_5(D)); |
60 | goto <bb 7>; |
61 | # SUCC: 7 [100.0%] (fallthru,exec) |
62 | |
63 | # BLOCK 4 freq:9000 |
64 | # PRED: 2 [90.0%] (false,exec) |
65 | # .MEMD.3923_16 = VDEF <.MEMD.3923_14> |
66 | # PT = nonlocal escaped |
67 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
68 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
69 | fpD.2605_8 = fopenD.1805 (&fileNameD.2604[0], 0B); |
70 | if (fpD.2605_8 == 0B) |
71 | goto <bb 5>; |
72 | else |
73 | goto <bb 6>; |
74 | # SUCC: 5 [1.9%] (true,exec) 6 [98.1%] (false,exec) |
75 | |
76 | # BLOCK 5 freq:173 |
77 | # PRED: 4 [1.9%] (true,exec) |
78 | # .MEMD.3923_17 = VDEF <.MEMD.3923_16> |
79 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
80 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
81 | freeD.898 (ctxD.2601_5(D)); |
82 | goto <bb 7>; |
83 | # SUCC: 7 [100.0%] (fallthru,exec) |
84 | |
85 | # BLOCK 6 freq:8827 |
86 | # PRED: 4 [98.1%] (false,exec) |
87 | # .MEMD.3923_18 = VDEF <.MEMD.3923_16> |
88 | # USE = nonlocal null { fileNameD.2604 D.3926 } (restr) |
89 | # CLB = nonlocal null { fileNameD.2604 D.3926 } (restr) |
90 | fooD.2599 (outputFileNameD.2600_2(D), fpD.2605_8); |
91 | # SUCC: 7 [100.0%] (fallthru,exec) |
92 | |
93 | # BLOCK 7 freq:10000 |
94 | # PRED: 3 [100.0%] (fallthru,exec) 5 [100.0%] (fallthru,exec) |
95 | 6 [100.0%] (fallthru,exec) |
96 | # PT = nonlocal null |
97 | |
98 | # ctxD.2601_1 = PHI <0B(3), 0B(5), ctxD.2601_5(D)(6)> |
99 | # .MEMD.3923_11 = PHI <.MEMD.3923_15(3), .MEMD.3923_17(5), |
100 | .MEMD.3923_18(6)> |
101 | # VUSE <.MEMD.3923_11> |
102 | return ctxD.2601_1; |
103 | # SUCC: EXIT [100.0%] |
104 | } |
105 | |
106 | bb 3 and bb 5 can be merged. The blocks have different predecessors, but the |
107 | same successors, and the same operations. |
108 | |
109 | |
110 | CONTEXT |
111 | |
112 | A technique called tail merging (or cross jumping) can fix the example |
113 | above. For a block, we look for common code at the end (the tail) of the |
114 | predecessor blocks, and insert jumps from one block to the other. |
115 | The example is a special case for tail merging, in that 2 whole blocks |
116 | can be merged, rather than just the end parts of it. |
117 | We currently only focus on whole block merging, so in that sense |
118 | calling this pass tail merge is a bit of a misnomer. |
119 | |
120 | We distinguish 2 kinds of situations in which blocks can be merged: |
121 | - same operations, same predecessors. The successor edges coming from one |
122 | block are redirected to come from the other block. |
123 | - same operations, same successors. The predecessor edges entering one block |
124 | are redirected to enter the other block. Note that this operation might |
125 | involve introducing phi operations. |
126 | |
127 | For efficient implementation, we would like to value numbers the blocks, and |
128 | have a comparison operator that tells us whether the blocks are equal. |
129 | Besides being runtime efficient, block value numbering should also abstract |
130 | from irrelevant differences in order of operations, much like normal value |
131 | numbering abstracts from irrelevant order of operations. |
132 | |
133 | For the first situation (same_operations, same predecessors), normal value |
134 | numbering fits well. We can calculate a block value number based on the |
135 | value numbers of the defs and vdefs. |
136 | |
137 | For the second situation (same operations, same successors), this approach |
138 | doesn't work so well. We can illustrate this using the example. The calls |
139 | to free use different vdefs: MEMD.3923_16 and MEMD.3923_14, and these will |
140 | remain different in value numbering, since they represent different memory |
141 | states. So the resulting vdefs of the frees will be different in value |
142 | numbering, so the block value numbers will be different. |
143 | |
144 | The reason why we call the blocks equal is not because they define the same |
145 | values, but because uses in the blocks use (possibly different) defs in the |
146 | same way. To be able to detect this efficiently, we need to do some kind of |
147 | reverse value numbering, meaning number the uses rather than the defs, and |
148 | calculate a block value number based on the value number of the uses. |
149 | Ideally, a block comparison operator will also indicate which phis are needed |
150 | to merge the blocks. |
151 | |
152 | For the moment, we don't do block value numbering, but we do insn-by-insn |
153 | matching, using scc value numbers to match operations with results, and |
154 | structural comparison otherwise, while ignoring vop mismatches. |
155 | |
156 | |
157 | IMPLEMENTATION |
158 | |
159 | 1. The pass first determines all groups of blocks with the same successor |
160 | blocks. |
161 | 2. Within each group, it tries to determine clusters of equal basic blocks. |
162 | 3. The clusters are applied. |
163 | 4. The same successor groups are updated. |
164 | 5. This process is repeated from 2 onwards, until no more changes. |
165 | |
166 | |
167 | LIMITATIONS/TODO |
168 | |
169 | - block only |
170 | - handles only 'same operations, same successors'. |
171 | It handles same predecessors as a special subcase though. |
172 | - does not implement the reverse value numbering and block value numbering. |
173 | - improve memory allocation: use garbage collected memory, obstacks, |
174 | allocpools where appropriate. |
175 | - no insertion of gimple_reg phis, We only introduce vop-phis. |
176 | - handle blocks with gimple_reg phi_nodes. |
177 | |
178 | |
179 | PASS PLACEMENT |
180 | This 'pass' is not a stand-alone gimple pass, but runs as part of |
181 | pass_pre, in order to share the value numbering. |
182 | |
183 | |
184 | SWITCHES |
185 | |
186 | - ftree-tail-merge. On at -O2. We may have to enable it only at -Os. */ |
187 | |
188 | #include "config.h" |
189 | #include "system.h" |
190 | #include "coretypes.h" |
191 | #include "backend.h" |
192 | #include "tree.h" |
193 | #include "gimple.h" |
194 | #include "cfghooks.h" |
195 | #include "tree-pass.h" |
196 | #include "ssa.h" |
197 | #include "fold-const.h" |
198 | #include "trans-mem.h" |
199 | #include "cfganal.h" |
200 | #include "cfgcleanup.h" |
201 | #include "gimple-iterator.h" |
202 | #include "tree-cfg.h" |
203 | #include "tree-into-ssa.h" |
204 | #include "params.h" |
205 | #include "tree-ssa-sccvn.h" |
206 | #include "cfgloop.h" |
207 | #include "tree-eh.h" |
208 | #include "tree-cfgcleanup.h" |
209 | |
210 | const int ignore_edge_flags = EDGE_DFS_BACK | EDGE_EXECUTABLE; |
211 | |
212 | /* Describes a group of bbs with the same successors. The successor bbs are |
213 | cached in succs, and the successor edge flags are cached in succ_flags. |
214 | If a bb has the EDGE_TRUE/FALSE_VALUE flags swapped compared to succ_flags, |
215 | it's marked in inverse. |
216 | Additionally, the hash value for the struct is cached in hashval, and |
217 | in_worklist indicates whether it's currently part of worklist. */ |
218 | |
219 | struct same_succ : pointer_hash <same_succ> |
220 | { |
221 | /* The bbs that have the same successor bbs. */ |
222 | bitmap bbs; |
223 | /* The successor bbs. */ |
224 | bitmap succs; |
225 | /* Indicates whether the EDGE_TRUE/FALSE_VALUEs of succ_flags are swapped for |
226 | bb. */ |
227 | bitmap inverse; |
228 | /* The edge flags for each of the successor bbs. */ |
229 | vec<int> succ_flags; |
230 | /* Indicates whether the struct is currently in the worklist. */ |
231 | bool in_worklist; |
232 | /* The hash value of the struct. */ |
233 | hashval_t hashval; |
234 | |
235 | /* hash_table support. */ |
236 | static inline hashval_t hash (const same_succ *); |
237 | static int equal (const same_succ *, const same_succ *); |
238 | static void remove (same_succ *); |
239 | }; |
240 | |
241 | /* hash routine for hash_table support, returns hashval of E. */ |
242 | |
243 | inline hashval_t |
244 | same_succ::hash (const same_succ *e) |
245 | { |
246 | return e->hashval; |
247 | } |
248 | |
249 | /* A group of bbs where 1 bb from bbs can replace the other bbs. */ |
250 | |
251 | struct bb_cluster |
252 | { |
253 | /* The bbs in the cluster. */ |
254 | bitmap bbs; |
255 | /* The preds of the bbs in the cluster. */ |
256 | bitmap preds; |
257 | /* Index in all_clusters vector. */ |
258 | int index; |
259 | /* The bb to replace the cluster with. */ |
260 | basic_block rep_bb; |
261 | }; |
262 | |
263 | /* Per bb-info. */ |
264 | |
265 | struct aux_bb_info |
266 | { |
267 | /* The number of non-debug statements in the bb. */ |
268 | int size; |
269 | /* The same_succ that this bb is a member of. */ |
270 | same_succ *bb_same_succ; |
271 | /* The cluster that this bb is a member of. */ |
272 | bb_cluster *cluster; |
273 | /* The vop state at the exit of a bb. This is shortlived data, used to |
274 | communicate data between update_block_by and update_vuses. */ |
275 | tree vop_at_exit; |
276 | /* The bb that either contains or is dominated by the dependencies of the |
277 | bb. */ |
278 | basic_block dep_bb; |
279 | }; |
280 | |
281 | /* Macros to access the fields of struct aux_bb_info. */ |
282 | |
283 | #define BB_SIZE(bb) (((struct aux_bb_info *)bb->aux)->size) |
284 | #define BB_SAME_SUCC(bb) (((struct aux_bb_info *)bb->aux)->bb_same_succ) |
285 | #define BB_CLUSTER(bb) (((struct aux_bb_info *)bb->aux)->cluster) |
286 | #define BB_VOP_AT_EXIT(bb) (((struct aux_bb_info *)bb->aux)->vop_at_exit) |
287 | #define BB_DEP_BB(bb) (((struct aux_bb_info *)bb->aux)->dep_bb) |
288 | |
289 | /* Returns true if the only effect a statement STMT has, is to define locally |
290 | used SSA_NAMEs. */ |
291 | |
292 | static bool |
293 | stmt_local_def (gimple *stmt) |
294 | { |
295 | basic_block bb, def_bb; |
296 | imm_use_iterator iter; |
297 | use_operand_p use_p; |
298 | tree val; |
299 | def_operand_p def_p; |
300 | |
301 | if (gimple_vdef (stmt) != NULL_TREE |
302 | || gimple_has_side_effects (stmt) |
303 | || gimple_could_trap_p_1 (stmt, false, false) |
304 | || gimple_vuse (stmt) != NULL_TREE) |
305 | return false; |
306 | |
307 | def_p = SINGLE_SSA_DEF_OPERAND (stmt, SSA_OP_DEF); |
308 | if (def_p == NULL) |
309 | return false; |
310 | |
311 | val = DEF_FROM_PTR (def_p); |
312 | if (val == NULL_TREE || TREE_CODE (val) != SSA_NAME) |
313 | return false; |
314 | |
315 | def_bb = gimple_bb (stmt); |
316 | |
317 | FOR_EACH_IMM_USE_FAST (use_p, iter, val) |
318 | { |
319 | if (is_gimple_debug (USE_STMT (use_p))) |
320 | continue; |
321 | bb = gimple_bb (USE_STMT (use_p)); |
322 | if (bb == def_bb) |
323 | continue; |
324 | |
325 | if (gimple_code (USE_STMT (use_p)) == GIMPLE_PHI |
326 | && EDGE_PRED (bb, PHI_ARG_INDEX_FROM_USE (use_p))->src == def_bb) |
327 | continue; |
328 | |
329 | return false; |
330 | } |
331 | |
332 | return true; |
333 | } |
334 | |
335 | /* Let GSI skip forwards over local defs. */ |
336 | |
337 | static void |
338 | gsi_advance_fw_nondebug_nonlocal (gimple_stmt_iterator *gsi) |
339 | { |
340 | gimple *stmt; |
341 | |
342 | while (true) |
343 | { |
344 | if (gsi_end_p (*gsi)) |
345 | return; |
346 | stmt = gsi_stmt (*gsi); |
347 | if (!stmt_local_def (stmt)) |
348 | return; |
349 | gsi_next_nondebug (gsi); |
350 | } |
351 | } |
352 | |
353 | /* VAL1 and VAL2 are either: |
354 | - uses in BB1 and BB2, or |
355 | - phi alternatives for BB1 and BB2. |
356 | Return true if the uses have the same gvn value. */ |
357 | |
358 | static bool |
359 | gvn_uses_equal (tree val1, tree val2) |
360 | { |
361 | gcc_checking_assert (val1 != NULL_TREE && val2 != NULL_TREE); |
362 | |
363 | if (val1 == val2) |
364 | return true; |
365 | |
366 | if (vn_valueize (val1) != vn_valueize (val2)) |
367 | return false; |
368 | |
369 | return ((TREE_CODE (val1) == SSA_NAME || CONSTANT_CLASS_P (val1)) |
370 | && (TREE_CODE (val2) == SSA_NAME || CONSTANT_CLASS_P (val2))); |
371 | } |
372 | |
373 | /* Prints E to FILE. */ |
374 | |
375 | static void |
376 | same_succ_print (FILE *file, const same_succ *e) |
377 | { |
378 | unsigned int i; |
379 | bitmap_print (file, e->bbs, "bbs:" , "\n" ); |
380 | bitmap_print (file, e->succs, "succs:" , "\n" ); |
381 | bitmap_print (file, e->inverse, "inverse:" , "\n" ); |
382 | fprintf (file, "flags:" ); |
383 | for (i = 0; i < e->succ_flags.length (); ++i) |
384 | fprintf (file, " %x" , e->succ_flags[i]); |
385 | fprintf (file, "\n" ); |
386 | } |
387 | |
388 | /* Prints same_succ VE to VFILE. */ |
389 | |
390 | inline int |
391 | ssa_same_succ_print_traverse (same_succ **pe, FILE *file) |
392 | { |
393 | const same_succ *e = *pe; |
394 | same_succ_print (file, e); |
395 | return 1; |
396 | } |
397 | |
398 | /* Update BB_DEP_BB (USE_BB), given a use of VAL in USE_BB. */ |
399 | |
400 | static void |
401 | update_dep_bb (basic_block use_bb, tree val) |
402 | { |
403 | basic_block dep_bb; |
404 | |
405 | /* Not a dep. */ |
406 | if (TREE_CODE (val) != SSA_NAME) |
407 | return; |
408 | |
409 | /* Skip use of global def. */ |
410 | if (SSA_NAME_IS_DEFAULT_DEF (val)) |
411 | return; |
412 | |
413 | /* Skip use of local def. */ |
414 | dep_bb = gimple_bb (SSA_NAME_DEF_STMT (val)); |
415 | if (dep_bb == use_bb) |
416 | return; |
417 | |
418 | if (BB_DEP_BB (use_bb) == NULL |
419 | || dominated_by_p (CDI_DOMINATORS, dep_bb, BB_DEP_BB (use_bb))) |
420 | BB_DEP_BB (use_bb) = dep_bb; |
421 | } |
422 | |
423 | /* Update BB_DEP_BB, given the dependencies in STMT. */ |
424 | |
425 | static void |
426 | stmt_update_dep_bb (gimple *stmt) |
427 | { |
428 | ssa_op_iter iter; |
429 | use_operand_p use; |
430 | |
431 | FOR_EACH_SSA_USE_OPERAND (use, stmt, iter, SSA_OP_USE) |
432 | update_dep_bb (gimple_bb (stmt), USE_FROM_PTR (use)); |
433 | } |
434 | |
435 | /* Calculates hash value for same_succ VE. */ |
436 | |
437 | static hashval_t |
438 | same_succ_hash (const same_succ *e) |
439 | { |
440 | inchash::hash hstate (bitmap_hash (e->succs)); |
441 | int flags; |
442 | unsigned int i; |
443 | unsigned int first = bitmap_first_set_bit (e->bbs); |
444 | basic_block bb = BASIC_BLOCK_FOR_FN (cfun, first); |
445 | int size = 0; |
446 | gimple *stmt; |
447 | tree arg; |
448 | unsigned int s; |
449 | bitmap_iterator bs; |
450 | |
451 | for (gimple_stmt_iterator gsi = gsi_start_nondebug_bb (bb); |
452 | !gsi_end_p (gsi); gsi_next_nondebug (&gsi)) |
453 | { |
454 | stmt = gsi_stmt (gsi); |
455 | stmt_update_dep_bb (stmt); |
456 | if (stmt_local_def (stmt)) |
457 | continue; |
458 | size++; |
459 | |
460 | hstate.add_int (gimple_code (stmt)); |
461 | if (is_gimple_assign (stmt)) |
462 | hstate.add_int (gimple_assign_rhs_code (stmt)); |
463 | if (!is_gimple_call (stmt)) |
464 | continue; |
465 | if (gimple_call_internal_p (stmt)) |
466 | hstate.add_int (gimple_call_internal_fn (stmt)); |
467 | else |
468 | { |
469 | inchash::add_expr (gimple_call_fn (stmt), hstate); |
470 | if (gimple_call_chain (stmt)) |
471 | inchash::add_expr (gimple_call_chain (stmt), hstate); |
472 | } |
473 | for (i = 0; i < gimple_call_num_args (stmt); i++) |
474 | { |
475 | arg = gimple_call_arg (stmt, i); |
476 | arg = vn_valueize (arg); |
477 | inchash::add_expr (arg, hstate); |
478 | } |
479 | } |
480 | |
481 | hstate.add_int (size); |
482 | BB_SIZE (bb) = size; |
483 | |
484 | hstate.add_int (bb->loop_father->num); |
485 | |
486 | for (i = 0; i < e->succ_flags.length (); ++i) |
487 | { |
488 | flags = e->succ_flags[i]; |
489 | flags = flags & ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); |
490 | hstate.add_int (flags); |
491 | } |
492 | |
493 | EXECUTE_IF_SET_IN_BITMAP (e->succs, 0, s, bs) |
494 | { |
495 | int n = find_edge (bb, BASIC_BLOCK_FOR_FN (cfun, s))->dest_idx; |
496 | for (gphi_iterator gsi = gsi_start_phis (BASIC_BLOCK_FOR_FN (cfun, s)); |
497 | !gsi_end_p (gsi); |
498 | gsi_next (&gsi)) |
499 | { |
500 | gphi *phi = gsi.phi (); |
501 | tree lhs = gimple_phi_result (phi); |
502 | tree val = gimple_phi_arg_def (phi, n); |
503 | |
504 | if (virtual_operand_p (lhs)) |
505 | continue; |
506 | update_dep_bb (bb, val); |
507 | } |
508 | } |
509 | |
510 | return hstate.end (); |
511 | } |
512 | |
513 | /* Returns true if E1 and E2 have 2 successors, and if the successor flags |
514 | are inverse for the EDGE_TRUE_VALUE and EDGE_FALSE_VALUE flags, and equal for |
515 | the other edge flags. */ |
516 | |
517 | static bool |
518 | inverse_flags (const same_succ *e1, const same_succ *e2) |
519 | { |
520 | int f1a, f1b, f2a, f2b; |
521 | int mask = ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); |
522 | |
523 | if (e1->succ_flags.length () != 2) |
524 | return false; |
525 | |
526 | f1a = e1->succ_flags[0]; |
527 | f1b = e1->succ_flags[1]; |
528 | f2a = e2->succ_flags[0]; |
529 | f2b = e2->succ_flags[1]; |
530 | |
531 | if (f1a == f2a && f1b == f2b) |
532 | return false; |
533 | |
534 | return (f1a & mask) == (f2a & mask) && (f1b & mask) == (f2b & mask); |
535 | } |
536 | |
537 | /* Compares SAME_SUCCs E1 and E2. */ |
538 | |
539 | int |
540 | same_succ::equal (const same_succ *e1, const same_succ *e2) |
541 | { |
542 | unsigned int i, first1, first2; |
543 | gimple_stmt_iterator gsi1, gsi2; |
544 | gimple *s1, *s2; |
545 | basic_block bb1, bb2; |
546 | |
547 | if (e1 == e2) |
548 | return 1; |
549 | |
550 | if (e1->hashval != e2->hashval) |
551 | return 0; |
552 | |
553 | if (e1->succ_flags.length () != e2->succ_flags.length ()) |
554 | return 0; |
555 | |
556 | if (!bitmap_equal_p (e1->succs, e2->succs)) |
557 | return 0; |
558 | |
559 | if (!inverse_flags (e1, e2)) |
560 | { |
561 | for (i = 0; i < e1->succ_flags.length (); ++i) |
562 | if (e1->succ_flags[i] != e2->succ_flags[i]) |
563 | return 0; |
564 | } |
565 | |
566 | first1 = bitmap_first_set_bit (e1->bbs); |
567 | first2 = bitmap_first_set_bit (e2->bbs); |
568 | |
569 | bb1 = BASIC_BLOCK_FOR_FN (cfun, first1); |
570 | bb2 = BASIC_BLOCK_FOR_FN (cfun, first2); |
571 | |
572 | if (BB_SIZE (bb1) != BB_SIZE (bb2)) |
573 | return 0; |
574 | |
575 | if (bb1->loop_father != bb2->loop_father) |
576 | return 0; |
577 | |
578 | gsi1 = gsi_start_nondebug_bb (bb1); |
579 | gsi2 = gsi_start_nondebug_bb (bb2); |
580 | gsi_advance_fw_nondebug_nonlocal (&gsi1); |
581 | gsi_advance_fw_nondebug_nonlocal (&gsi2); |
582 | while (!(gsi_end_p (gsi1) || gsi_end_p (gsi2))) |
583 | { |
584 | s1 = gsi_stmt (gsi1); |
585 | s2 = gsi_stmt (gsi2); |
586 | if (gimple_code (s1) != gimple_code (s2)) |
587 | return 0; |
588 | if (is_gimple_call (s1) && !gimple_call_same_target_p (s1, s2)) |
589 | return 0; |
590 | gsi_next_nondebug (&gsi1); |
591 | gsi_next_nondebug (&gsi2); |
592 | gsi_advance_fw_nondebug_nonlocal (&gsi1); |
593 | gsi_advance_fw_nondebug_nonlocal (&gsi2); |
594 | } |
595 | |
596 | return 1; |
597 | } |
598 | |
599 | /* Alloc and init a new SAME_SUCC. */ |
600 | |
601 | static same_succ * |
602 | same_succ_alloc (void) |
603 | { |
604 | same_succ *same = XNEW (struct same_succ); |
605 | |
606 | same->bbs = BITMAP_ALLOC (NULL); |
607 | same->succs = BITMAP_ALLOC (NULL); |
608 | same->inverse = BITMAP_ALLOC (NULL); |
609 | same->succ_flags.create (10); |
610 | same->in_worklist = false; |
611 | |
612 | return same; |
613 | } |
614 | |
615 | /* Delete same_succ E. */ |
616 | |
617 | void |
618 | same_succ::remove (same_succ *e) |
619 | { |
620 | BITMAP_FREE (e->bbs); |
621 | BITMAP_FREE (e->succs); |
622 | BITMAP_FREE (e->inverse); |
623 | e->succ_flags.release (); |
624 | |
625 | XDELETE (e); |
626 | } |
627 | |
628 | /* Reset same_succ SAME. */ |
629 | |
630 | static void |
631 | same_succ_reset (same_succ *same) |
632 | { |
633 | bitmap_clear (same->bbs); |
634 | bitmap_clear (same->succs); |
635 | bitmap_clear (same->inverse); |
636 | same->succ_flags.truncate (0); |
637 | } |
638 | |
639 | static hash_table<same_succ> *same_succ_htab; |
640 | |
641 | /* Array that is used to store the edge flags for a successor. */ |
642 | |
643 | static int *same_succ_edge_flags; |
644 | |
645 | /* Bitmap that is used to mark bbs that are recently deleted. */ |
646 | |
647 | static bitmap deleted_bbs; |
648 | |
649 | /* Bitmap that is used to mark predecessors of bbs that are |
650 | deleted. */ |
651 | |
652 | static bitmap deleted_bb_preds; |
653 | |
654 | /* Prints same_succ_htab to stderr. */ |
655 | |
656 | extern void debug_same_succ (void); |
657 | DEBUG_FUNCTION void |
658 | debug_same_succ ( void) |
659 | { |
660 | same_succ_htab->traverse <FILE *, ssa_same_succ_print_traverse> (stderr); |
661 | } |
662 | |
663 | |
664 | /* Vector of bbs to process. */ |
665 | |
666 | static vec<same_succ *> worklist; |
667 | |
668 | /* Prints worklist to FILE. */ |
669 | |
670 | static void |
671 | print_worklist (FILE *file) |
672 | { |
673 | unsigned int i; |
674 | for (i = 0; i < worklist.length (); ++i) |
675 | same_succ_print (file, worklist[i]); |
676 | } |
677 | |
678 | /* Adds SAME to worklist. */ |
679 | |
680 | static void |
681 | add_to_worklist (same_succ *same) |
682 | { |
683 | if (same->in_worklist) |
684 | return; |
685 | |
686 | if (bitmap_count_bits (same->bbs) < 2) |
687 | return; |
688 | |
689 | same->in_worklist = true; |
690 | worklist.safe_push (same); |
691 | } |
692 | |
693 | /* Add BB to same_succ_htab. */ |
694 | |
695 | static void |
696 | find_same_succ_bb (basic_block bb, same_succ **same_p) |
697 | { |
698 | unsigned int j; |
699 | bitmap_iterator bj; |
700 | same_succ *same = *same_p; |
701 | same_succ **slot; |
702 | edge_iterator ei; |
703 | edge e; |
704 | |
705 | if (bb == NULL) |
706 | return; |
707 | bitmap_set_bit (same->bbs, bb->index); |
708 | FOR_EACH_EDGE (e, ei, bb->succs) |
709 | { |
710 | int index = e->dest->index; |
711 | bitmap_set_bit (same->succs, index); |
712 | same_succ_edge_flags[index] = (e->flags & ~ignore_edge_flags); |
713 | } |
714 | EXECUTE_IF_SET_IN_BITMAP (same->succs, 0, j, bj) |
715 | same->succ_flags.safe_push (same_succ_edge_flags[j]); |
716 | |
717 | same->hashval = same_succ_hash (same); |
718 | |
719 | slot = same_succ_htab->find_slot_with_hash (same, same->hashval, INSERT); |
720 | if (*slot == NULL) |
721 | { |
722 | *slot = same; |
723 | BB_SAME_SUCC (bb) = same; |
724 | add_to_worklist (same); |
725 | *same_p = NULL; |
726 | } |
727 | else |
728 | { |
729 | bitmap_set_bit ((*slot)->bbs, bb->index); |
730 | BB_SAME_SUCC (bb) = *slot; |
731 | add_to_worklist (*slot); |
732 | if (inverse_flags (same, *slot)) |
733 | bitmap_set_bit ((*slot)->inverse, bb->index); |
734 | same_succ_reset (same); |
735 | } |
736 | } |
737 | |
738 | /* Find bbs with same successors. */ |
739 | |
740 | static void |
741 | find_same_succ (void) |
742 | { |
743 | same_succ *same = same_succ_alloc (); |
744 | basic_block bb; |
745 | |
746 | FOR_EACH_BB_FN (bb, cfun) |
747 | { |
748 | find_same_succ_bb (bb, &same); |
749 | if (same == NULL) |
750 | same = same_succ_alloc (); |
751 | } |
752 | |
753 | same_succ::remove (same); |
754 | } |
755 | |
756 | /* Initializes worklist administration. */ |
757 | |
758 | static void |
759 | init_worklist (void) |
760 | { |
761 | alloc_aux_for_blocks (sizeof (struct aux_bb_info)); |
762 | same_succ_htab = new hash_table<same_succ> (n_basic_blocks_for_fn (cfun)); |
763 | same_succ_edge_flags = XCNEWVEC (int, last_basic_block_for_fn (cfun)); |
764 | deleted_bbs = BITMAP_ALLOC (NULL); |
765 | deleted_bb_preds = BITMAP_ALLOC (NULL); |
766 | worklist.create (n_basic_blocks_for_fn (cfun)); |
767 | find_same_succ (); |
768 | |
769 | if (dump_file && (dump_flags & TDF_DETAILS)) |
770 | { |
771 | fprintf (dump_file, "initial worklist:\n" ); |
772 | print_worklist (dump_file); |
773 | } |
774 | } |
775 | |
776 | /* Deletes worklist administration. */ |
777 | |
778 | static void |
779 | delete_worklist (void) |
780 | { |
781 | free_aux_for_blocks (); |
782 | delete same_succ_htab; |
783 | same_succ_htab = NULL; |
784 | XDELETEVEC (same_succ_edge_flags); |
785 | same_succ_edge_flags = NULL; |
786 | BITMAP_FREE (deleted_bbs); |
787 | BITMAP_FREE (deleted_bb_preds); |
788 | worklist.release (); |
789 | } |
790 | |
791 | /* Mark BB as deleted, and mark its predecessors. */ |
792 | |
793 | static void |
794 | mark_basic_block_deleted (basic_block bb) |
795 | { |
796 | edge e; |
797 | edge_iterator ei; |
798 | |
799 | bitmap_set_bit (deleted_bbs, bb->index); |
800 | |
801 | FOR_EACH_EDGE (e, ei, bb->preds) |
802 | bitmap_set_bit (deleted_bb_preds, e->src->index); |
803 | } |
804 | |
805 | /* Removes BB from its corresponding same_succ. */ |
806 | |
807 | static void |
808 | same_succ_flush_bb (basic_block bb) |
809 | { |
810 | same_succ *same = BB_SAME_SUCC (bb); |
811 | if (! same) |
812 | return; |
813 | |
814 | BB_SAME_SUCC (bb) = NULL; |
815 | if (bitmap_single_bit_set_p (same->bbs)) |
816 | same_succ_htab->remove_elt_with_hash (same, same->hashval); |
817 | else |
818 | bitmap_clear_bit (same->bbs, bb->index); |
819 | } |
820 | |
821 | /* Removes all bbs in BBS from their corresponding same_succ. */ |
822 | |
823 | static void |
824 | same_succ_flush_bbs (bitmap bbs) |
825 | { |
826 | unsigned int i; |
827 | bitmap_iterator bi; |
828 | |
829 | EXECUTE_IF_SET_IN_BITMAP (bbs, 0, i, bi) |
830 | same_succ_flush_bb (BASIC_BLOCK_FOR_FN (cfun, i)); |
831 | } |
832 | |
833 | /* Release the last vdef in BB, either normal or phi result. */ |
834 | |
835 | static void |
836 | release_last_vdef (basic_block bb) |
837 | { |
838 | for (gimple_stmt_iterator i = gsi_last_bb (bb); !gsi_end_p (i); |
839 | gsi_prev_nondebug (&i)) |
840 | { |
841 | gimple *stmt = gsi_stmt (i); |
842 | if (gimple_vdef (stmt) == NULL_TREE) |
843 | continue; |
844 | |
845 | mark_virtual_operand_for_renaming (gimple_vdef (stmt)); |
846 | return; |
847 | } |
848 | |
849 | for (gphi_iterator i = gsi_start_phis (bb); !gsi_end_p (i); |
850 | gsi_next (&i)) |
851 | { |
852 | gphi *phi = i.phi (); |
853 | tree res = gimple_phi_result (phi); |
854 | |
855 | if (!virtual_operand_p (res)) |
856 | continue; |
857 | |
858 | mark_virtual_phi_result_for_renaming (phi); |
859 | return; |
860 | } |
861 | } |
862 | |
863 | /* For deleted_bb_preds, find bbs with same successors. */ |
864 | |
865 | static void |
866 | update_worklist (void) |
867 | { |
868 | unsigned int i; |
869 | bitmap_iterator bi; |
870 | basic_block bb; |
871 | same_succ *same; |
872 | |
873 | bitmap_and_compl_into (deleted_bb_preds, deleted_bbs); |
874 | bitmap_clear (deleted_bbs); |
875 | |
876 | bitmap_clear_bit (deleted_bb_preds, ENTRY_BLOCK); |
877 | same_succ_flush_bbs (deleted_bb_preds); |
878 | |
879 | same = same_succ_alloc (); |
880 | EXECUTE_IF_SET_IN_BITMAP (deleted_bb_preds, 0, i, bi) |
881 | { |
882 | bb = BASIC_BLOCK_FOR_FN (cfun, i); |
883 | gcc_assert (bb != NULL); |
884 | find_same_succ_bb (bb, &same); |
885 | if (same == NULL) |
886 | same = same_succ_alloc (); |
887 | } |
888 | same_succ::remove (same); |
889 | bitmap_clear (deleted_bb_preds); |
890 | } |
891 | |
892 | /* Prints cluster C to FILE. */ |
893 | |
894 | static void |
895 | print_cluster (FILE *file, bb_cluster *c) |
896 | { |
897 | if (c == NULL) |
898 | return; |
899 | bitmap_print (file, c->bbs, "bbs:" , "\n" ); |
900 | bitmap_print (file, c->preds, "preds:" , "\n" ); |
901 | } |
902 | |
903 | /* Prints cluster C to stderr. */ |
904 | |
905 | extern void debug_cluster (bb_cluster *); |
906 | DEBUG_FUNCTION void |
907 | debug_cluster (bb_cluster *c) |
908 | { |
909 | print_cluster (stderr, c); |
910 | } |
911 | |
912 | /* Update C->rep_bb, given that BB is added to the cluster. */ |
913 | |
914 | static void |
915 | update_rep_bb (bb_cluster *c, basic_block bb) |
916 | { |
917 | /* Initial. */ |
918 | if (c->rep_bb == NULL) |
919 | { |
920 | c->rep_bb = bb; |
921 | return; |
922 | } |
923 | |
924 | /* Current needs no deps, keep it. */ |
925 | if (BB_DEP_BB (c->rep_bb) == NULL) |
926 | return; |
927 | |
928 | /* Bb needs no deps, change rep_bb. */ |
929 | if (BB_DEP_BB (bb) == NULL) |
930 | { |
931 | c->rep_bb = bb; |
932 | return; |
933 | } |
934 | |
935 | /* Bb needs last deps earlier than current, change rep_bb. A potential |
936 | problem with this, is that the first deps might also be earlier, which |
937 | would mean we prefer longer lifetimes for the deps. To be able to check |
938 | for this, we would have to trace BB_FIRST_DEP_BB as well, besides |
939 | BB_DEP_BB, which is really BB_LAST_DEP_BB. |
940 | The benefit of choosing the bb with last deps earlier, is that it can |
941 | potentially be used as replacement for more bbs. */ |
942 | if (dominated_by_p (CDI_DOMINATORS, BB_DEP_BB (c->rep_bb), BB_DEP_BB (bb))) |
943 | c->rep_bb = bb; |
944 | } |
945 | |
946 | /* Add BB to cluster C. Sets BB in C->bbs, and preds of BB in C->preds. */ |
947 | |
948 | static void |
949 | add_bb_to_cluster (bb_cluster *c, basic_block bb) |
950 | { |
951 | edge e; |
952 | edge_iterator ei; |
953 | |
954 | bitmap_set_bit (c->bbs, bb->index); |
955 | |
956 | FOR_EACH_EDGE (e, ei, bb->preds) |
957 | bitmap_set_bit (c->preds, e->src->index); |
958 | |
959 | update_rep_bb (c, bb); |
960 | } |
961 | |
962 | /* Allocate and init new cluster. */ |
963 | |
964 | static bb_cluster * |
965 | new_cluster (void) |
966 | { |
967 | bb_cluster *c; |
968 | c = XCNEW (bb_cluster); |
969 | c->bbs = BITMAP_ALLOC (NULL); |
970 | c->preds = BITMAP_ALLOC (NULL); |
971 | c->rep_bb = NULL; |
972 | return c; |
973 | } |
974 | |
975 | /* Delete clusters. */ |
976 | |
977 | static void |
978 | delete_cluster (bb_cluster *c) |
979 | { |
980 | if (c == NULL) |
981 | return; |
982 | BITMAP_FREE (c->bbs); |
983 | BITMAP_FREE (c->preds); |
984 | XDELETE (c); |
985 | } |
986 | |
987 | |
988 | /* Array that contains all clusters. */ |
989 | |
990 | static vec<bb_cluster *> all_clusters; |
991 | |
992 | /* Allocate all cluster vectors. */ |
993 | |
994 | static void |
995 | alloc_cluster_vectors (void) |
996 | { |
997 | all_clusters.create (n_basic_blocks_for_fn (cfun)); |
998 | } |
999 | |
1000 | /* Reset all cluster vectors. */ |
1001 | |
1002 | static void |
1003 | reset_cluster_vectors (void) |
1004 | { |
1005 | unsigned int i; |
1006 | basic_block bb; |
1007 | for (i = 0; i < all_clusters.length (); ++i) |
1008 | delete_cluster (all_clusters[i]); |
1009 | all_clusters.truncate (0); |
1010 | FOR_EACH_BB_FN (bb, cfun) |
1011 | BB_CLUSTER (bb) = NULL; |
1012 | } |
1013 | |
1014 | /* Delete all cluster vectors. */ |
1015 | |
1016 | static void |
1017 | delete_cluster_vectors (void) |
1018 | { |
1019 | unsigned int i; |
1020 | for (i = 0; i < all_clusters.length (); ++i) |
1021 | delete_cluster (all_clusters[i]); |
1022 | all_clusters.release (); |
1023 | } |
1024 | |
1025 | /* Merge cluster C2 into C1. */ |
1026 | |
1027 | static void |
1028 | merge_clusters (bb_cluster *c1, bb_cluster *c2) |
1029 | { |
1030 | bitmap_ior_into (c1->bbs, c2->bbs); |
1031 | bitmap_ior_into (c1->preds, c2->preds); |
1032 | } |
1033 | |
1034 | /* Register equivalence of BB1 and BB2 (members of cluster C). Store c in |
1035 | all_clusters, or merge c with existing cluster. */ |
1036 | |
1037 | static void |
1038 | set_cluster (basic_block bb1, basic_block bb2) |
1039 | { |
1040 | basic_block merge_bb, other_bb; |
1041 | bb_cluster *merge, *old, *c; |
1042 | |
1043 | if (BB_CLUSTER (bb1) == NULL && BB_CLUSTER (bb2) == NULL) |
1044 | { |
1045 | c = new_cluster (); |
1046 | add_bb_to_cluster (c, bb1); |
1047 | add_bb_to_cluster (c, bb2); |
1048 | BB_CLUSTER (bb1) = c; |
1049 | BB_CLUSTER (bb2) = c; |
1050 | c->index = all_clusters.length (); |
1051 | all_clusters.safe_push (c); |
1052 | } |
1053 | else if (BB_CLUSTER (bb1) == NULL || BB_CLUSTER (bb2) == NULL) |
1054 | { |
1055 | merge_bb = BB_CLUSTER (bb1) == NULL ? bb2 : bb1; |
1056 | other_bb = BB_CLUSTER (bb1) == NULL ? bb1 : bb2; |
1057 | merge = BB_CLUSTER (merge_bb); |
1058 | add_bb_to_cluster (merge, other_bb); |
1059 | BB_CLUSTER (other_bb) = merge; |
1060 | } |
1061 | else if (BB_CLUSTER (bb1) != BB_CLUSTER (bb2)) |
1062 | { |
1063 | unsigned int i; |
1064 | bitmap_iterator bi; |
1065 | |
1066 | old = BB_CLUSTER (bb2); |
1067 | merge = BB_CLUSTER (bb1); |
1068 | merge_clusters (merge, old); |
1069 | EXECUTE_IF_SET_IN_BITMAP (old->bbs, 0, i, bi) |
1070 | BB_CLUSTER (BASIC_BLOCK_FOR_FN (cfun, i)) = merge; |
1071 | all_clusters[old->index] = NULL; |
1072 | update_rep_bb (merge, old->rep_bb); |
1073 | delete_cluster (old); |
1074 | } |
1075 | else |
1076 | gcc_unreachable (); |
1077 | } |
1078 | |
1079 | /* Return true if gimple operands T1 and T2 have the same value. */ |
1080 | |
1081 | static bool |
1082 | gimple_operand_equal_value_p (tree t1, tree t2) |
1083 | { |
1084 | if (t1 == t2) |
1085 | return true; |
1086 | |
1087 | if (t1 == NULL_TREE |
1088 | || t2 == NULL_TREE) |
1089 | return false; |
1090 | |
1091 | if (operand_equal_p (t1, t2, OEP_MATCH_SIDE_EFFECTS)) |
1092 | return true; |
1093 | |
1094 | return gvn_uses_equal (t1, t2); |
1095 | } |
1096 | |
1097 | /* Return true if gimple statements S1 and S2 are equal. Gimple_bb (s1) and |
1098 | gimple_bb (s2) are members of SAME_SUCC. */ |
1099 | |
1100 | static bool |
1101 | gimple_equal_p (same_succ *same_succ, gimple *s1, gimple *s2) |
1102 | { |
1103 | unsigned int i; |
1104 | tree lhs1, lhs2; |
1105 | basic_block bb1 = gimple_bb (s1), bb2 = gimple_bb (s2); |
1106 | tree t1, t2; |
1107 | bool inv_cond; |
1108 | enum tree_code code1, code2; |
1109 | |
1110 | if (gimple_code (s1) != gimple_code (s2)) |
1111 | return false; |
1112 | |
1113 | switch (gimple_code (s1)) |
1114 | { |
1115 | case GIMPLE_CALL: |
1116 | if (!gimple_call_same_target_p (s1, s2)) |
1117 | return false; |
1118 | |
1119 | t1 = gimple_call_chain (s1); |
1120 | t2 = gimple_call_chain (s2); |
1121 | if (!gimple_operand_equal_value_p (t1, t2)) |
1122 | return false; |
1123 | |
1124 | if (gimple_call_num_args (s1) != gimple_call_num_args (s2)) |
1125 | return false; |
1126 | |
1127 | for (i = 0; i < gimple_call_num_args (s1); ++i) |
1128 | { |
1129 | t1 = gimple_call_arg (s1, i); |
1130 | t2 = gimple_call_arg (s2, i); |
1131 | if (!gimple_operand_equal_value_p (t1, t2)) |
1132 | return false; |
1133 | } |
1134 | |
1135 | lhs1 = gimple_get_lhs (s1); |
1136 | lhs2 = gimple_get_lhs (s2); |
1137 | if (lhs1 == NULL_TREE && lhs2 == NULL_TREE) |
1138 | return true; |
1139 | if (lhs1 == NULL_TREE || lhs2 == NULL_TREE) |
1140 | return false; |
1141 | if (TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME) |
1142 | return vn_valueize (lhs1) == vn_valueize (lhs2); |
1143 | return operand_equal_p (lhs1, lhs2, 0); |
1144 | |
1145 | case GIMPLE_ASSIGN: |
1146 | lhs1 = gimple_get_lhs (s1); |
1147 | lhs2 = gimple_get_lhs (s2); |
1148 | if (TREE_CODE (lhs1) != SSA_NAME |
1149 | && TREE_CODE (lhs2) != SSA_NAME) |
1150 | return (operand_equal_p (lhs1, lhs2, 0) |
1151 | && gimple_operand_equal_value_p (gimple_assign_rhs1 (s1), |
1152 | gimple_assign_rhs1 (s2))); |
1153 | else if (TREE_CODE (lhs1) == SSA_NAME |
1154 | && TREE_CODE (lhs2) == SSA_NAME) |
1155 | return operand_equal_p (gimple_assign_rhs1 (s1), |
1156 | gimple_assign_rhs1 (s2), 0); |
1157 | return false; |
1158 | |
1159 | case GIMPLE_COND: |
1160 | t1 = gimple_cond_lhs (s1); |
1161 | t2 = gimple_cond_lhs (s2); |
1162 | if (!gimple_operand_equal_value_p (t1, t2)) |
1163 | return false; |
1164 | |
1165 | t1 = gimple_cond_rhs (s1); |
1166 | t2 = gimple_cond_rhs (s2); |
1167 | if (!gimple_operand_equal_value_p (t1, t2)) |
1168 | return false; |
1169 | |
1170 | code1 = gimple_expr_code (s1); |
1171 | code2 = gimple_expr_code (s2); |
1172 | inv_cond = (bitmap_bit_p (same_succ->inverse, bb1->index) |
1173 | != bitmap_bit_p (same_succ->inverse, bb2->index)); |
1174 | if (inv_cond) |
1175 | { |
1176 | bool honor_nans = HONOR_NANS (t1); |
1177 | code2 = invert_tree_comparison (code2, honor_nans); |
1178 | } |
1179 | return code1 == code2; |
1180 | |
1181 | default: |
1182 | return false; |
1183 | } |
1184 | } |
1185 | |
1186 | /* Let GSI skip backwards over local defs. Return the earliest vuse in VUSE. |
1187 | Return true in VUSE_ESCAPED if the vuse influenced a SSA_OP_DEF of one of the |
1188 | processed statements. */ |
1189 | |
1190 | static void |
1191 | gsi_advance_bw_nondebug_nonlocal (gimple_stmt_iterator *gsi, tree *vuse, |
1192 | bool *vuse_escaped) |
1193 | { |
1194 | gimple *stmt; |
1195 | tree lvuse; |
1196 | |
1197 | while (true) |
1198 | { |
1199 | if (gsi_end_p (*gsi)) |
1200 | return; |
1201 | stmt = gsi_stmt (*gsi); |
1202 | |
1203 | lvuse = gimple_vuse (stmt); |
1204 | if (lvuse != NULL_TREE) |
1205 | { |
1206 | *vuse = lvuse; |
1207 | if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_DEF)) |
1208 | *vuse_escaped = true; |
1209 | } |
1210 | |
1211 | if (!stmt_local_def (stmt)) |
1212 | return; |
1213 | gsi_prev_nondebug (gsi); |
1214 | } |
1215 | } |
1216 | |
1217 | /* Return true if equal (in the sense of gimple_equal_p) statements STMT1 and |
1218 | STMT2 are allowed to be merged. */ |
1219 | |
1220 | static bool |
1221 | merge_stmts_p (gimple *stmt1, gimple *stmt2) |
1222 | { |
1223 | /* What could be better than this here is to blacklist the bb |
1224 | containing the stmt, when encountering the stmt f.i. in |
1225 | same_succ_hash. */ |
1226 | if (is_tm_ending (stmt1)) |
1227 | return false; |
1228 | |
1229 | /* Verify EH landing pads. */ |
1230 | if (lookup_stmt_eh_lp_fn (cfun, stmt1) != lookup_stmt_eh_lp_fn (cfun, stmt2)) |
1231 | return false; |
1232 | |
1233 | if (is_gimple_call (stmt1) |
1234 | && gimple_call_internal_p (stmt1)) |
1235 | switch (gimple_call_internal_fn (stmt1)) |
1236 | { |
1237 | case IFN_UBSAN_NULL: |
1238 | case IFN_UBSAN_BOUNDS: |
1239 | case IFN_UBSAN_VPTR: |
1240 | case IFN_UBSAN_CHECK_ADD: |
1241 | case IFN_UBSAN_CHECK_SUB: |
1242 | case IFN_UBSAN_CHECK_MUL: |
1243 | case IFN_UBSAN_OBJECT_SIZE: |
1244 | case IFN_UBSAN_PTR: |
1245 | case IFN_ASAN_CHECK: |
1246 | /* For these internal functions, gimple_location is an implicit |
1247 | parameter, which will be used explicitly after expansion. |
1248 | Merging these statements may cause confusing line numbers in |
1249 | sanitizer messages. */ |
1250 | return gimple_location (stmt1) == gimple_location (stmt2); |
1251 | default: |
1252 | break; |
1253 | } |
1254 | |
1255 | return true; |
1256 | } |
1257 | |
1258 | /* Determines whether BB1 and BB2 (members of same_succ) are duplicates. If so, |
1259 | clusters them. */ |
1260 | |
1261 | static void |
1262 | find_duplicate (same_succ *same_succ, basic_block bb1, basic_block bb2) |
1263 | { |
1264 | gimple_stmt_iterator gsi1 = gsi_last_nondebug_bb (bb1); |
1265 | gimple_stmt_iterator gsi2 = gsi_last_nondebug_bb (bb2); |
1266 | tree vuse1 = NULL_TREE, vuse2 = NULL_TREE; |
1267 | bool vuse_escaped = false; |
1268 | |
1269 | gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1, &vuse_escaped); |
1270 | gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2, &vuse_escaped); |
1271 | |
1272 | while (!gsi_end_p (gsi1) && !gsi_end_p (gsi2)) |
1273 | { |
1274 | gimple *stmt1 = gsi_stmt (gsi1); |
1275 | gimple *stmt2 = gsi_stmt (gsi2); |
1276 | |
1277 | if (gimple_code (stmt1) == GIMPLE_LABEL |
1278 | && gimple_code (stmt2) == GIMPLE_LABEL) |
1279 | break; |
1280 | |
1281 | if (!gimple_equal_p (same_succ, stmt1, stmt2)) |
1282 | return; |
1283 | |
1284 | if (!merge_stmts_p (stmt1, stmt2)) |
1285 | return; |
1286 | |
1287 | gsi_prev_nondebug (&gsi1); |
1288 | gsi_prev_nondebug (&gsi2); |
1289 | gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1, &vuse_escaped); |
1290 | gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2, &vuse_escaped); |
1291 | } |
1292 | |
1293 | while (!gsi_end_p (gsi1) && gimple_code (gsi_stmt (gsi1)) == GIMPLE_LABEL) |
1294 | { |
1295 | tree label = gimple_label_label (as_a <glabel *> (gsi_stmt (gsi1))); |
1296 | if (DECL_NONLOCAL (label) || FORCED_LABEL (label)) |
1297 | return; |
1298 | gsi_prev_nondebug (&gsi1); |
1299 | } |
1300 | while (!gsi_end_p (gsi2) && gimple_code (gsi_stmt (gsi2)) == GIMPLE_LABEL) |
1301 | { |
1302 | tree label = gimple_label_label (as_a <glabel *> (gsi_stmt (gsi2))); |
1303 | if (DECL_NONLOCAL (label) || FORCED_LABEL (label)) |
1304 | return; |
1305 | gsi_prev_nondebug (&gsi2); |
1306 | } |
1307 | if (!(gsi_end_p (gsi1) && gsi_end_p (gsi2))) |
1308 | return; |
1309 | |
1310 | /* If the incoming vuses are not the same, and the vuse escaped into an |
1311 | SSA_OP_DEF, then merging the 2 blocks will change the value of the def, |
1312 | which potentially means the semantics of one of the blocks will be changed. |
1313 | TODO: make this check more precise. */ |
1314 | if (vuse_escaped && vuse1 != vuse2) |
1315 | return; |
1316 | |
1317 | if (dump_file) |
1318 | fprintf (dump_file, "find_duplicates: <bb %d> duplicate of <bb %d>\n" , |
1319 | bb1->index, bb2->index); |
1320 | |
1321 | set_cluster (bb1, bb2); |
1322 | } |
1323 | |
1324 | /* Returns whether for all phis in DEST the phi alternatives for E1 and |
1325 | E2 are equal. */ |
1326 | |
1327 | static bool |
1328 | same_phi_alternatives_1 (basic_block dest, edge e1, edge e2) |
1329 | { |
1330 | int n1 = e1->dest_idx, n2 = e2->dest_idx; |
1331 | gphi_iterator gsi; |
1332 | |
1333 | for (gsi = gsi_start_phis (dest); !gsi_end_p (gsi); gsi_next (&gsi)) |
1334 | { |
1335 | gphi *phi = gsi.phi (); |
1336 | tree lhs = gimple_phi_result (phi); |
1337 | tree val1 = gimple_phi_arg_def (phi, n1); |
1338 | tree val2 = gimple_phi_arg_def (phi, n2); |
1339 | |
1340 | if (virtual_operand_p (lhs)) |
1341 | continue; |
1342 | |
1343 | if (operand_equal_for_phi_arg_p (val1, val2)) |
1344 | continue; |
1345 | if (gvn_uses_equal (val1, val2)) |
1346 | continue; |
1347 | |
1348 | return false; |
1349 | } |
1350 | |
1351 | return true; |
1352 | } |
1353 | |
1354 | /* Returns whether for all successors of BB1 and BB2 (members of SAME_SUCC), the |
1355 | phi alternatives for BB1 and BB2 are equal. */ |
1356 | |
1357 | static bool |
1358 | same_phi_alternatives (same_succ *same_succ, basic_block bb1, basic_block bb2) |
1359 | { |
1360 | unsigned int s; |
1361 | bitmap_iterator bs; |
1362 | edge e1, e2; |
1363 | basic_block succ; |
1364 | |
1365 | EXECUTE_IF_SET_IN_BITMAP (same_succ->succs, 0, s, bs) |
1366 | { |
1367 | succ = BASIC_BLOCK_FOR_FN (cfun, s); |
1368 | e1 = find_edge (bb1, succ); |
1369 | e2 = find_edge (bb2, succ); |
1370 | if (e1->flags & EDGE_COMPLEX |
1371 | || e2->flags & EDGE_COMPLEX) |
1372 | return false; |
1373 | |
1374 | /* For all phis in bb, the phi alternatives for e1 and e2 need to have |
1375 | the same value. */ |
1376 | if (!same_phi_alternatives_1 (succ, e1, e2)) |
1377 | return false; |
1378 | } |
1379 | |
1380 | return true; |
1381 | } |
1382 | |
1383 | /* Return true if BB has non-vop phis. */ |
1384 | |
1385 | static bool |
1386 | bb_has_non_vop_phi (basic_block bb) |
1387 | { |
1388 | gimple_seq phis = phi_nodes (bb); |
1389 | gimple *phi; |
1390 | |
1391 | if (phis == NULL) |
1392 | return false; |
1393 | |
1394 | if (!gimple_seq_singleton_p (phis)) |
1395 | return true; |
1396 | |
1397 | phi = gimple_seq_first_stmt (phis); |
1398 | return !virtual_operand_p (gimple_phi_result (phi)); |
1399 | } |
1400 | |
1401 | /* Returns true if redirecting the incoming edges of FROM to TO maintains the |
1402 | invariant that uses in FROM are dominates by their defs. */ |
1403 | |
1404 | static bool |
1405 | deps_ok_for_redirect_from_bb_to_bb (basic_block from, basic_block to) |
1406 | { |
1407 | basic_block cd, dep_bb = BB_DEP_BB (to); |
1408 | edge_iterator ei; |
1409 | edge e; |
1410 | |
1411 | if (dep_bb == NULL) |
1412 | return true; |
1413 | |
1414 | bitmap from_preds = BITMAP_ALLOC (NULL); |
1415 | FOR_EACH_EDGE (e, ei, from->preds) |
1416 | bitmap_set_bit (from_preds, e->src->index); |
1417 | cd = nearest_common_dominator_for_set (CDI_DOMINATORS, from_preds); |
1418 | BITMAP_FREE (from_preds); |
1419 | |
1420 | return dominated_by_p (CDI_DOMINATORS, dep_bb, cd); |
1421 | } |
1422 | |
1423 | /* Returns true if replacing BB1 (or its replacement bb) by BB2 (or its |
1424 | replacement bb) and vice versa maintains the invariant that uses in the |
1425 | replacement are dominates by their defs. */ |
1426 | |
1427 | static bool |
1428 | deps_ok_for_redirect (basic_block bb1, basic_block bb2) |
1429 | { |
1430 | if (BB_CLUSTER (bb1) != NULL) |
1431 | bb1 = BB_CLUSTER (bb1)->rep_bb; |
1432 | |
1433 | if (BB_CLUSTER (bb2) != NULL) |
1434 | bb2 = BB_CLUSTER (bb2)->rep_bb; |
1435 | |
1436 | return (deps_ok_for_redirect_from_bb_to_bb (bb1, bb2) |
1437 | && deps_ok_for_redirect_from_bb_to_bb (bb2, bb1)); |
1438 | } |
1439 | |
1440 | /* Within SAME_SUCC->bbs, find clusters of bbs which can be merged. */ |
1441 | |
1442 | static void |
1443 | find_clusters_1 (same_succ *same_succ) |
1444 | { |
1445 | basic_block bb1, bb2; |
1446 | unsigned int i, j; |
1447 | bitmap_iterator bi, bj; |
1448 | int nr_comparisons; |
1449 | int max_comparisons = PARAM_VALUE (PARAM_MAX_TAIL_MERGE_COMPARISONS); |
1450 | |
1451 | EXECUTE_IF_SET_IN_BITMAP (same_succ->bbs, 0, i, bi) |
1452 | { |
1453 | bb1 = BASIC_BLOCK_FOR_FN (cfun, i); |
1454 | |
1455 | /* TODO: handle blocks with phi-nodes. We'll have to find corresponding |
1456 | phi-nodes in bb1 and bb2, with the same alternatives for the same |
1457 | preds. */ |
1458 | if (bb_has_non_vop_phi (bb1) || bb_has_eh_pred (bb1)) |
1459 | continue; |
1460 | |
1461 | nr_comparisons = 0; |
1462 | EXECUTE_IF_SET_IN_BITMAP (same_succ->bbs, i + 1, j, bj) |
1463 | { |
1464 | bb2 = BASIC_BLOCK_FOR_FN (cfun, j); |
1465 | |
1466 | if (bb_has_non_vop_phi (bb2) || bb_has_eh_pred (bb2)) |
1467 | continue; |
1468 | |
1469 | if (BB_CLUSTER (bb1) != NULL && BB_CLUSTER (bb1) == BB_CLUSTER (bb2)) |
1470 | continue; |
1471 | |
1472 | /* Limit quadratic behavior. */ |
1473 | nr_comparisons++; |
1474 | if (nr_comparisons > max_comparisons) |
1475 | break; |
1476 | |
1477 | /* This is a conservative dependency check. We could test more |
1478 | precise for allowed replacement direction. */ |
1479 | if (!deps_ok_for_redirect (bb1, bb2)) |
1480 | continue; |
1481 | |
1482 | if (!(same_phi_alternatives (same_succ, bb1, bb2))) |
1483 | continue; |
1484 | |
1485 | find_duplicate (same_succ, bb1, bb2); |
1486 | } |
1487 | } |
1488 | } |
1489 | |
1490 | /* Find clusters of bbs which can be merged. */ |
1491 | |
1492 | static void |
1493 | find_clusters (void) |
1494 | { |
1495 | same_succ *same; |
1496 | |
1497 | while (!worklist.is_empty ()) |
1498 | { |
1499 | same = worklist.pop (); |
1500 | same->in_worklist = false; |
1501 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1502 | { |
1503 | fprintf (dump_file, "processing worklist entry\n" ); |
1504 | same_succ_print (dump_file, same); |
1505 | } |
1506 | find_clusters_1 (same); |
1507 | } |
1508 | } |
1509 | |
1510 | /* Returns the vop phi of BB, if any. */ |
1511 | |
1512 | static gphi * |
1513 | vop_phi (basic_block bb) |
1514 | { |
1515 | gphi *stmt; |
1516 | gphi_iterator gsi; |
1517 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
1518 | { |
1519 | stmt = gsi.phi (); |
1520 | if (! virtual_operand_p (gimple_phi_result (stmt))) |
1521 | continue; |
1522 | return stmt; |
1523 | } |
1524 | return NULL; |
1525 | } |
1526 | |
1527 | /* Redirect all edges from BB1 to BB2, removes BB1 and marks it as removed. */ |
1528 | |
1529 | static void |
1530 | replace_block_by (basic_block bb1, basic_block bb2) |
1531 | { |
1532 | edge pred_edge; |
1533 | unsigned int i; |
1534 | gphi *bb2_phi; |
1535 | |
1536 | bb2_phi = vop_phi (bb2); |
1537 | |
1538 | /* Mark the basic block as deleted. */ |
1539 | mark_basic_block_deleted (bb1); |
1540 | |
1541 | /* Redirect the incoming edges of bb1 to bb2. */ |
1542 | for (i = EDGE_COUNT (bb1->preds); i > 0 ; --i) |
1543 | { |
1544 | pred_edge = EDGE_PRED (bb1, i - 1); |
1545 | pred_edge = redirect_edge_and_branch (pred_edge, bb2); |
1546 | gcc_assert (pred_edge != NULL); |
1547 | |
1548 | if (bb2_phi == NULL) |
1549 | continue; |
1550 | |
1551 | /* The phi might have run out of capacity when the redirect added an |
1552 | argument, which means it could have been replaced. Refresh it. */ |
1553 | bb2_phi = vop_phi (bb2); |
1554 | |
1555 | add_phi_arg (bb2_phi, SSA_NAME_VAR (gimple_phi_result (bb2_phi)), |
1556 | pred_edge, UNKNOWN_LOCATION); |
1557 | } |
1558 | |
1559 | |
1560 | /* Merge the outgoing edge counts from bb1 onto bb2. */ |
1561 | edge e1, e2; |
1562 | edge_iterator ei; |
1563 | |
1564 | if (bb2->count.initialized_p ()) |
1565 | FOR_EACH_EDGE (e1, ei, bb1->succs) |
1566 | { |
1567 | e2 = find_edge (bb2, e1->dest); |
1568 | gcc_assert (e2); |
1569 | |
1570 | /* If probabilities are same, we are done. |
1571 | If counts are nonzero we can distribute accordingly. In remaining |
1572 | cases just avreage the values and hope for the best. */ |
1573 | if (e1->probability == e2->probability) |
1574 | ; |
1575 | else if (bb1->count.nonzero_p () || bb2->count.nonzero_p ()) |
1576 | e2->probability |
1577 | = e2->probability |
1578 | * bb2->count.probability_in (bb1->count + bb2->count) |
1579 | + e1->probability |
1580 | * bb1->count.probability_in (bb1->count + bb2->count); |
1581 | else |
1582 | e2->probability = e2->probability * profile_probability::even () |
1583 | + e1->probability * profile_probability::even (); |
1584 | } |
1585 | bb2->count += bb1->count; |
1586 | |
1587 | /* Move over any user labels from bb1 after the bb2 labels. */ |
1588 | gimple_stmt_iterator gsi1 = gsi_start_bb (bb1); |
1589 | if (!gsi_end_p (gsi1) && gimple_code (gsi_stmt (gsi1)) == GIMPLE_LABEL) |
1590 | { |
1591 | gimple_stmt_iterator gsi2 = gsi_after_labels (bb2); |
1592 | while (!gsi_end_p (gsi1) |
1593 | && gimple_code (gsi_stmt (gsi1)) == GIMPLE_LABEL) |
1594 | { |
1595 | tree label = gimple_label_label (as_a <glabel *> (gsi_stmt (gsi1))); |
1596 | gcc_assert (!DECL_NONLOCAL (label) && !FORCED_LABEL (label)); |
1597 | if (DECL_ARTIFICIAL (label)) |
1598 | gsi_next (&gsi1); |
1599 | else |
1600 | gsi_move_before (&gsi1, &gsi2); |
1601 | } |
1602 | } |
1603 | |
1604 | /* Clear range info from all stmts in BB2 -- this transformation |
1605 | could make them out of date. */ |
1606 | reset_flow_sensitive_info_in_bb (bb2); |
1607 | |
1608 | /* Do updates that use bb1, before deleting bb1. */ |
1609 | release_last_vdef (bb1); |
1610 | same_succ_flush_bb (bb1); |
1611 | |
1612 | delete_basic_block (bb1); |
1613 | } |
1614 | |
1615 | /* Bbs for which update_debug_stmt need to be called. */ |
1616 | |
1617 | static bitmap update_bbs; |
1618 | |
1619 | /* For each cluster in all_clusters, merge all cluster->bbs. Returns |
1620 | number of bbs removed. */ |
1621 | |
1622 | static int |
1623 | apply_clusters (void) |
1624 | { |
1625 | basic_block bb1, bb2; |
1626 | bb_cluster *c; |
1627 | unsigned int i, j; |
1628 | bitmap_iterator bj; |
1629 | int nr_bbs_removed = 0; |
1630 | |
1631 | for (i = 0; i < all_clusters.length (); ++i) |
1632 | { |
1633 | c = all_clusters[i]; |
1634 | if (c == NULL) |
1635 | continue; |
1636 | |
1637 | bb2 = c->rep_bb; |
1638 | bitmap_set_bit (update_bbs, bb2->index); |
1639 | |
1640 | bitmap_clear_bit (c->bbs, bb2->index); |
1641 | EXECUTE_IF_SET_IN_BITMAP (c->bbs, 0, j, bj) |
1642 | { |
1643 | bb1 = BASIC_BLOCK_FOR_FN (cfun, j); |
1644 | bitmap_clear_bit (update_bbs, bb1->index); |
1645 | |
1646 | replace_block_by (bb1, bb2); |
1647 | nr_bbs_removed++; |
1648 | } |
1649 | } |
1650 | |
1651 | return nr_bbs_removed; |
1652 | } |
1653 | |
1654 | /* Resets debug statement STMT if it has uses that are not dominated by their |
1655 | defs. */ |
1656 | |
1657 | static void |
1658 | update_debug_stmt (gimple *stmt) |
1659 | { |
1660 | use_operand_p use_p; |
1661 | ssa_op_iter oi; |
1662 | basic_block bbuse; |
1663 | |
1664 | if (!gimple_debug_bind_p (stmt)) |
1665 | return; |
1666 | |
1667 | bbuse = gimple_bb (stmt); |
1668 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, oi, SSA_OP_USE) |
1669 | { |
1670 | tree name = USE_FROM_PTR (use_p); |
1671 | gimple *def_stmt = SSA_NAME_DEF_STMT (name); |
1672 | basic_block bbdef = gimple_bb (def_stmt); |
1673 | if (bbdef == NULL || bbuse == bbdef |
1674 | || dominated_by_p (CDI_DOMINATORS, bbuse, bbdef)) |
1675 | continue; |
1676 | |
1677 | gimple_debug_bind_reset_value (stmt); |
1678 | update_stmt (stmt); |
1679 | break; |
1680 | } |
1681 | } |
1682 | |
1683 | /* Resets all debug statements that have uses that are not |
1684 | dominated by their defs. */ |
1685 | |
1686 | static void |
1687 | update_debug_stmts (void) |
1688 | { |
1689 | basic_block bb; |
1690 | bitmap_iterator bi; |
1691 | unsigned int i; |
1692 | |
1693 | EXECUTE_IF_SET_IN_BITMAP (update_bbs, 0, i, bi) |
1694 | { |
1695 | gimple *stmt; |
1696 | gimple_stmt_iterator gsi; |
1697 | |
1698 | bb = BASIC_BLOCK_FOR_FN (cfun, i); |
1699 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
1700 | { |
1701 | stmt = gsi_stmt (gsi); |
1702 | if (!is_gimple_debug (stmt)) |
1703 | continue; |
1704 | update_debug_stmt (stmt); |
1705 | } |
1706 | } |
1707 | } |
1708 | |
1709 | /* Runs tail merge optimization. */ |
1710 | |
1711 | unsigned int |
1712 | tail_merge_optimize (unsigned int todo) |
1713 | { |
1714 | int nr_bbs_removed_total = 0; |
1715 | int nr_bbs_removed; |
1716 | bool loop_entered = false; |
1717 | int iteration_nr = 0; |
1718 | int max_iterations = PARAM_VALUE (PARAM_MAX_TAIL_MERGE_ITERATIONS); |
1719 | |
1720 | if (!flag_tree_tail_merge |
1721 | || max_iterations == 0) |
1722 | return 0; |
1723 | |
1724 | timevar_push (TV_TREE_TAIL_MERGE); |
1725 | |
1726 | /* We enter from PRE which has critical edges split. Elimination |
1727 | does not process trivially dead code so cleanup the CFG if we |
1728 | are told so. And re-split critical edges then. */ |
1729 | if (todo & TODO_cleanup_cfg) |
1730 | { |
1731 | cleanup_tree_cfg (); |
1732 | todo &= ~TODO_cleanup_cfg; |
1733 | split_critical_edges (); |
1734 | } |
1735 | |
1736 | if (!dom_info_available_p (CDI_DOMINATORS)) |
1737 | { |
1738 | /* PRE can leave us with unreachable blocks, remove them now. */ |
1739 | delete_unreachable_blocks (); |
1740 | calculate_dominance_info (CDI_DOMINATORS); |
1741 | } |
1742 | init_worklist (); |
1743 | |
1744 | while (!worklist.is_empty ()) |
1745 | { |
1746 | if (!loop_entered) |
1747 | { |
1748 | loop_entered = true; |
1749 | alloc_cluster_vectors (); |
1750 | update_bbs = BITMAP_ALLOC (NULL); |
1751 | } |
1752 | else |
1753 | reset_cluster_vectors (); |
1754 | |
1755 | iteration_nr++; |
1756 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1757 | fprintf (dump_file, "worklist iteration #%d\n" , iteration_nr); |
1758 | |
1759 | find_clusters (); |
1760 | gcc_assert (worklist.is_empty ()); |
1761 | if (all_clusters.is_empty ()) |
1762 | break; |
1763 | |
1764 | nr_bbs_removed = apply_clusters (); |
1765 | nr_bbs_removed_total += nr_bbs_removed; |
1766 | if (nr_bbs_removed == 0) |
1767 | break; |
1768 | |
1769 | free_dominance_info (CDI_DOMINATORS); |
1770 | |
1771 | if (iteration_nr == max_iterations) |
1772 | break; |
1773 | |
1774 | calculate_dominance_info (CDI_DOMINATORS); |
1775 | update_worklist (); |
1776 | } |
1777 | |
1778 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1779 | fprintf (dump_file, "htab collision / search: %f\n" , |
1780 | same_succ_htab->collisions ()); |
1781 | |
1782 | if (nr_bbs_removed_total > 0) |
1783 | { |
1784 | if (MAY_HAVE_DEBUG_BIND_STMTS) |
1785 | { |
1786 | calculate_dominance_info (CDI_DOMINATORS); |
1787 | update_debug_stmts (); |
1788 | } |
1789 | |
1790 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1791 | { |
1792 | fprintf (dump_file, "Before TODOs.\n" ); |
1793 | dump_function_to_file (current_function_decl, dump_file, dump_flags); |
1794 | } |
1795 | |
1796 | mark_virtual_operands_for_renaming (cfun); |
1797 | } |
1798 | |
1799 | delete_worklist (); |
1800 | if (loop_entered) |
1801 | { |
1802 | delete_cluster_vectors (); |
1803 | BITMAP_FREE (update_bbs); |
1804 | } |
1805 | |
1806 | timevar_pop (TV_TREE_TAIL_MERGE); |
1807 | |
1808 | return todo; |
1809 | } |
1810 | |