]>
Commit | Line | Data |
---|---|---|
4ee9c684 | 1 | /* Optimization of PHI nodes by converting them into straightline code. |
711789cc | 2 | Copyright (C) 2004-2013 Free Software Foundation, Inc. |
4ee9c684 | 3 | |
4 | This file is part of GCC. | |
20e5647c | 5 | |
4ee9c684 | 6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 8 | Free Software Foundation; either version 3, or (at your option) any |
4ee9c684 | 9 | later version. |
20e5647c | 10 | |
4ee9c684 | 11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
12 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
20e5647c | 15 | |
4ee9c684 | 16 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
d9dd21a8 | 23 | #include "hash-table.h" |
4ee9c684 | 24 | #include "tm.h" |
4ee9c684 | 25 | #include "tree.h" |
9ed99284 | 26 | #include "stor-layout.h" |
0beac6fc | 27 | #include "flags.h" |
4ee9c684 | 28 | #include "tm_p.h" |
29 | #include "basic-block.h" | |
bc61cadb | 30 | #include "pointer-set.h" |
31 | #include "tree-ssa-alias.h" | |
32 | #include "internal-fn.h" | |
33 | #include "gimple-expr.h" | |
34 | #include "is-a.h" | |
e795d6e1 | 35 | #include "gimple.h" |
a8783bee | 36 | #include "gimplify.h" |
dcf1a1ec | 37 | #include "gimple-iterator.h" |
e795d6e1 | 38 | #include "gimplify-me.h" |
073c1fd5 | 39 | #include "gimple-ssa.h" |
40 | #include "tree-cfg.h" | |
41 | #include "tree-phinodes.h" | |
42 | #include "ssa-iterators.h" | |
9ed99284 | 43 | #include "stringpool.h" |
073c1fd5 | 44 | #include "tree-ssanames.h" |
9ed99284 | 45 | #include "expr.h" |
073c1fd5 | 46 | #include "tree-dfa.h" |
4ee9c684 | 47 | #include "tree-pass.h" |
4ee9c684 | 48 | #include "langhooks.h" |
e6d0e152 | 49 | #include "domwalk.h" |
ec611e12 | 50 | #include "cfgloop.h" |
51 | #include "tree-data-ref.h" | |
239e9670 | 52 | #include "gimple-pretty-print.h" |
53 | #include "insn-config.h" | |
54 | #include "expr.h" | |
55 | #include "optabs.h" | |
f6568ea4 | 56 | #include "tree-scalar-evolution.h" |
239e9670 | 57 | |
58 | #ifndef HAVE_conditional_move | |
59 | #define HAVE_conditional_move (0) | |
60 | #endif | |
4ee9c684 | 61 | |
75a70cf9 | 62 | static unsigned int tree_ssa_phiopt (void); |
239e9670 | 63 | static unsigned int tree_ssa_phiopt_worker (bool, bool); |
a4844041 | 64 | static bool conditional_replacement (basic_block, basic_block, |
75a70cf9 | 65 | edge, edge, gimple, tree, tree); |
fb9912ea | 66 | static int value_replacement (basic_block, basic_block, |
67 | edge, edge, gimple, tree, tree); | |
a4844041 | 68 | static bool minmax_replacement (basic_block, basic_block, |
75a70cf9 | 69 | edge, edge, gimple, tree, tree); |
a4844041 | 70 | static bool abs_replacement (basic_block, basic_block, |
75a70cf9 | 71 | edge, edge, gimple, tree, tree); |
e6d0e152 | 72 | static bool cond_store_replacement (basic_block, basic_block, edge, edge, |
73 | struct pointer_set_t *); | |
91cf53d5 | 74 | static bool cond_if_else_store_replacement (basic_block, basic_block, basic_block); |
e6d0e152 | 75 | static struct pointer_set_t * get_non_trapping (void); |
75a70cf9 | 76 | static void replace_phi_edge_with_variable (basic_block, edge, gimple, tree); |
239e9670 | 77 | static void hoist_adjacent_loads (basic_block, basic_block, |
78 | basic_block, basic_block); | |
79 | static bool gate_hoist_loads (void); | |
902929aa | 80 | |
caac37c2 | 81 | /* This pass tries to replaces an if-then-else block with an |
82 | assignment. We have four kinds of transformations. Some of these | |
83 | transformations are also performed by the ifcvt RTL optimizer. | |
84 | ||
85 | Conditional Replacement | |
86 | ----------------------- | |
87 | ||
30c5ffd2 | 88 | This transformation, implemented in conditional_replacement, |
caac37c2 | 89 | replaces |
4ee9c684 | 90 | |
91 | bb0: | |
92 | if (cond) goto bb2; else goto bb1; | |
93 | bb1: | |
94 | bb2: | |
caac37c2 | 95 | x = PHI <0 (bb1), 1 (bb0), ...>; |
4ee9c684 | 96 | |
caac37c2 | 97 | with |
20e5647c | 98 | |
2ab0a163 | 99 | bb0: |
caac37c2 | 100 | x' = cond; |
101 | goto bb2; | |
2ab0a163 | 102 | bb2: |
caac37c2 | 103 | x = PHI <x' (bb0), ...>; |
4ee9c684 | 104 | |
caac37c2 | 105 | We remove bb1 as it becomes unreachable. This occurs often due to |
106 | gimplification of conditionals. | |
20e5647c | 107 | |
caac37c2 | 108 | Value Replacement |
109 | ----------------- | |
110 | ||
111 | This transformation, implemented in value_replacement, replaces | |
0beac6fc | 112 | |
113 | bb0: | |
caac37c2 | 114 | if (a != b) goto bb2; else goto bb1; |
0beac6fc | 115 | bb1: |
116 | bb2: | |
caac37c2 | 117 | x = PHI <a (bb1), b (bb0), ...>; |
0beac6fc | 118 | |
caac37c2 | 119 | with |
0beac6fc | 120 | |
121 | bb0: | |
0beac6fc | 122 | bb2: |
caac37c2 | 123 | x = PHI <b (bb0), ...>; |
124 | ||
125 | This opportunity can sometimes occur as a result of other | |
126 | optimizations. | |
0beac6fc | 127 | |
f32420fb | 128 | |
129 | Another case caught by value replacement looks like this: | |
130 | ||
131 | bb0: | |
132 | t1 = a == CONST; | |
133 | t2 = b > c; | |
134 | t3 = t1 & t2; | |
135 | if (t3 != 0) goto bb1; else goto bb2; | |
136 | bb1: | |
137 | bb2: | |
138 | x = PHI (CONST, a) | |
139 | ||
140 | Gets replaced with: | |
141 | bb0: | |
142 | bb2: | |
143 | t1 = a == CONST; | |
144 | t2 = b > c; | |
145 | t3 = t1 & t2; | |
146 | x = a; | |
147 | ||
caac37c2 | 148 | ABS Replacement |
149 | --------------- | |
70512b93 | 150 | |
caac37c2 | 151 | This transformation, implemented in abs_replacement, replaces |
70512b93 | 152 | |
153 | bb0: | |
caac37c2 | 154 | if (a >= 0) goto bb2; else goto bb1; |
70512b93 | 155 | bb1: |
caac37c2 | 156 | x = -a; |
70512b93 | 157 | bb2: |
caac37c2 | 158 | x = PHI <x (bb1), a (bb0), ...>; |
70512b93 | 159 | |
caac37c2 | 160 | with |
70512b93 | 161 | |
162 | bb0: | |
caac37c2 | 163 | x' = ABS_EXPR< a >; |
70512b93 | 164 | bb2: |
caac37c2 | 165 | x = PHI <x' (bb0), ...>; |
166 | ||
167 | MIN/MAX Replacement | |
168 | ------------------- | |
70512b93 | 169 | |
caac37c2 | 170 | This transformation, minmax_replacement replaces |
194899bf | 171 | |
172 | bb0: | |
caac37c2 | 173 | if (a <= b) goto bb2; else goto bb1; |
194899bf | 174 | bb1: |
194899bf | 175 | bb2: |
caac37c2 | 176 | x = PHI <b (bb1), a (bb0), ...>; |
194899bf | 177 | |
caac37c2 | 178 | with |
194899bf | 179 | |
caac37c2 | 180 | bb0: |
181 | x' = MIN_EXPR (a, b) | |
182 | bb2: | |
183 | x = PHI <x' (bb0), ...>; | |
194899bf | 184 | |
239e9670 | 185 | A similar transformation is done for MAX_EXPR. |
186 | ||
187 | ||
188 | This pass also performs a fifth transformation of a slightly different | |
189 | flavor. | |
190 | ||
191 | Adjacent Load Hoisting | |
192 | ---------------------- | |
f32420fb | 193 | |
239e9670 | 194 | This transformation replaces |
195 | ||
196 | bb0: | |
197 | if (...) goto bb2; else goto bb1; | |
198 | bb1: | |
199 | x1 = (<expr>).field1; | |
200 | goto bb3; | |
201 | bb2: | |
202 | x2 = (<expr>).field2; | |
203 | bb3: | |
204 | # x = PHI <x1, x2>; | |
205 | ||
206 | with | |
207 | ||
208 | bb0: | |
209 | x1 = (<expr>).field1; | |
210 | x2 = (<expr>).field2; | |
211 | if (...) goto bb2; else goto bb1; | |
212 | bb1: | |
213 | goto bb3; | |
214 | bb2: | |
215 | bb3: | |
216 | # x = PHI <x1, x2>; | |
217 | ||
218 | The purpose of this transformation is to enable generation of conditional | |
219 | move instructions such as Intel CMOVE or PowerPC ISEL. Because one of | |
220 | the loads is speculative, the transformation is restricted to very | |
221 | specific cases to avoid introducing a page fault. We are looking for | |
222 | the common idiom: | |
223 | ||
224 | if (...) | |
225 | x = y->left; | |
226 | else | |
227 | x = y->right; | |
228 | ||
229 | where left and right are typically adjacent pointers in a tree structure. */ | |
70512b93 | 230 | |
2a1990e9 | 231 | static unsigned int |
4ee9c684 | 232 | tree_ssa_phiopt (void) |
e6d0e152 | 233 | { |
239e9670 | 234 | return tree_ssa_phiopt_worker (false, gate_hoist_loads ()); |
e6d0e152 | 235 | } |
236 | ||
237 | /* This pass tries to transform conditional stores into unconditional | |
238 | ones, enabling further simplifications with the simpler then and else | |
239 | blocks. In particular it replaces this: | |
240 | ||
241 | bb0: | |
242 | if (cond) goto bb2; else goto bb1; | |
243 | bb1: | |
91cf53d5 | 244 | *p = RHS; |
e6d0e152 | 245 | bb2: |
246 | ||
247 | with | |
248 | ||
249 | bb0: | |
250 | if (cond) goto bb1; else goto bb2; | |
251 | bb1: | |
252 | condtmp' = *p; | |
253 | bb2: | |
254 | condtmp = PHI <RHS, condtmp'> | |
91cf53d5 | 255 | *p = condtmp; |
e6d0e152 | 256 | |
257 | This transformation can only be done under several constraints, | |
91cf53d5 | 258 | documented below. It also replaces: |
259 | ||
260 | bb0: | |
261 | if (cond) goto bb2; else goto bb1; | |
262 | bb1: | |
263 | *p = RHS1; | |
264 | goto bb3; | |
265 | bb2: | |
266 | *p = RHS2; | |
267 | bb3: | |
268 | ||
269 | with | |
270 | ||
271 | bb0: | |
272 | if (cond) goto bb3; else goto bb1; | |
273 | bb1: | |
274 | bb3: | |
275 | condtmp = PHI <RHS1, RHS2> | |
276 | *p = condtmp; */ | |
e6d0e152 | 277 | |
278 | static unsigned int | |
279 | tree_ssa_cs_elim (void) | |
280 | { | |
f6568ea4 | 281 | unsigned todo; |
282 | /* ??? We are not interested in loop related info, but the following | |
283 | will create it, ICEing as we didn't init loops with pre-headers. | |
284 | An interfacing issue of find_data_references_in_bb. */ | |
285 | loop_optimizer_init (LOOPS_NORMAL); | |
286 | scev_initialize (); | |
287 | todo = tree_ssa_phiopt_worker (true, false); | |
288 | scev_finalize (); | |
289 | loop_optimizer_finalize (); | |
290 | return todo; | |
e6d0e152 | 291 | } |
292 | ||
c3597b05 | 293 | /* Return the singleton PHI in the SEQ of PHIs for edges E0 and E1. */ |
294 | ||
295 | static gimple | |
296 | single_non_singleton_phi_for_edges (gimple_seq seq, edge e0, edge e1) | |
297 | { | |
298 | gimple_stmt_iterator i; | |
299 | gimple phi = NULL; | |
300 | if (gimple_seq_singleton_p (seq)) | |
301 | return gsi_stmt (gsi_start (seq)); | |
302 | for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i)) | |
303 | { | |
304 | gimple p = gsi_stmt (i); | |
305 | /* If the PHI arguments are equal then we can skip this PHI. */ | |
306 | if (operand_equal_for_phi_arg_p (gimple_phi_arg_def (p, e0->dest_idx), | |
307 | gimple_phi_arg_def (p, e1->dest_idx))) | |
308 | continue; | |
309 | ||
310 | /* If we already have a PHI that has the two edge arguments are | |
311 | different, then return it is not a singleton for these PHIs. */ | |
312 | if (phi) | |
313 | return NULL; | |
314 | ||
315 | phi = p; | |
316 | } | |
317 | return phi; | |
318 | } | |
319 | ||
e6d0e152 | 320 | /* The core routine of conditional store replacement and normal |
321 | phi optimizations. Both share much of the infrastructure in how | |
322 | to match applicable basic block patterns. DO_STORE_ELIM is true | |
239e9670 | 323 | when we want to do conditional store replacement, false otherwise. |
f32420fb | 324 | DO_HOIST_LOADS is true when we want to hoist adjacent loads out |
239e9670 | 325 | of diamond control flow patterns, false otherwise. */ |
e6d0e152 | 326 | static unsigned int |
239e9670 | 327 | tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads) |
4ee9c684 | 328 | { |
329 | basic_block bb; | |
194899bf | 330 | basic_block *bb_order; |
331 | unsigned n, i; | |
1e4b21e3 | 332 | bool cfgchanged = false; |
e6d0e152 | 333 | struct pointer_set_t *nontrap = 0; |
334 | ||
335 | if (do_store_elim) | |
03d37e4e | 336 | /* Calculate the set of non-trapping memory accesses. */ |
337 | nontrap = get_non_trapping (); | |
194899bf | 338 | |
339 | /* Search every basic block for COND_EXPR we may be able to optimize. | |
340 | ||
341 | We walk the blocks in order that guarantees that a block with | |
342 | a single predecessor is processed before the predecessor. | |
343 | This ensures that we collapse inner ifs before visiting the | |
344 | outer ones, and also that we do not try to visit a removed | |
345 | block. */ | |
ba4d2b2f | 346 | bb_order = single_pred_before_succ_order (); |
a28770e1 | 347 | n = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; |
4ee9c684 | 348 | |
48e1416a | 349 | for (i = 0; i < n; i++) |
4ee9c684 | 350 | { |
75a70cf9 | 351 | gimple cond_stmt, phi; |
33784d89 | 352 | basic_block bb1, bb2; |
353 | edge e1, e2; | |
194899bf | 354 | tree arg0, arg1; |
355 | ||
356 | bb = bb_order[i]; | |
20e5647c | 357 | |
75a70cf9 | 358 | cond_stmt = last_stmt (bb); |
359 | /* Check to see if the last statement is a GIMPLE_COND. */ | |
360 | if (!cond_stmt | |
361 | || gimple_code (cond_stmt) != GIMPLE_COND) | |
33784d89 | 362 | continue; |
20e5647c | 363 | |
33784d89 | 364 | e1 = EDGE_SUCC (bb, 0); |
365 | bb1 = e1->dest; | |
366 | e2 = EDGE_SUCC (bb, 1); | |
367 | bb2 = e2->dest; | |
20e5647c | 368 | |
33784d89 | 369 | /* We cannot do the optimization on abnormal edges. */ |
370 | if ((e1->flags & EDGE_ABNORMAL) != 0 | |
371 | || (e2->flags & EDGE_ABNORMAL) != 0) | |
372 | continue; | |
20e5647c | 373 | |
33784d89 | 374 | /* If either bb1's succ or bb2 or bb2's succ is non NULL. */ |
ea091dfd | 375 | if (EDGE_COUNT (bb1->succs) == 0 |
33784d89 | 376 | || bb2 == NULL |
ea091dfd | 377 | || EDGE_COUNT (bb2->succs) == 0) |
33784d89 | 378 | continue; |
20e5647c | 379 | |
33784d89 | 380 | /* Find the bb which is the fall through to the other. */ |
381 | if (EDGE_SUCC (bb1, 0)->dest == bb2) | |
382 | ; | |
383 | else if (EDGE_SUCC (bb2, 0)->dest == bb1) | |
384 | { | |
385 | basic_block bb_tmp = bb1; | |
386 | edge e_tmp = e1; | |
387 | bb1 = bb2; | |
388 | bb2 = bb_tmp; | |
389 | e1 = e2; | |
390 | e2 = e_tmp; | |
391 | } | |
91cf53d5 | 392 | else if (do_store_elim |
393 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) | |
394 | { | |
395 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
396 | ||
397 | if (!single_succ_p (bb1) | |
398 | || (EDGE_SUCC (bb1, 0)->flags & EDGE_FALLTHRU) == 0 | |
399 | || !single_succ_p (bb2) | |
400 | || (EDGE_SUCC (bb2, 0)->flags & EDGE_FALLTHRU) == 0 | |
401 | || EDGE_COUNT (bb3->preds) != 2) | |
402 | continue; | |
403 | if (cond_if_else_store_replacement (bb1, bb2, bb3)) | |
404 | cfgchanged = true; | |
405 | continue; | |
406 | } | |
239e9670 | 407 | else if (do_hoist_loads |
408 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) | |
409 | { | |
410 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
411 | ||
412 | if (!FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt))) | |
413 | && single_succ_p (bb1) | |
414 | && single_succ_p (bb2) | |
415 | && single_pred_p (bb1) | |
416 | && single_pred_p (bb2) | |
417 | && EDGE_COUNT (bb->succs) == 2 | |
418 | && EDGE_COUNT (bb3->preds) == 2 | |
419 | /* If one edge or the other is dominant, a conditional move | |
420 | is likely to perform worse than the well-predicted branch. */ | |
421 | && !predictable_edge_p (EDGE_SUCC (bb, 0)) | |
422 | && !predictable_edge_p (EDGE_SUCC (bb, 1))) | |
423 | hoist_adjacent_loads (bb, bb1, bb2, bb3); | |
424 | continue; | |
425 | } | |
33784d89 | 426 | else |
f32420fb | 427 | continue; |
20e5647c | 428 | |
33784d89 | 429 | e1 = EDGE_SUCC (bb1, 0); |
20e5647c | 430 | |
33784d89 | 431 | /* Make sure that bb1 is just a fall through. */ |
db5ba14c | 432 | if (!single_succ_p (bb1) |
33784d89 | 433 | || (e1->flags & EDGE_FALLTHRU) == 0) |
434 | continue; | |
20e5647c | 435 | |
3472707f | 436 | /* Also make sure that bb1 only have one predecessor and that it |
437 | is bb. */ | |
ea091dfd | 438 | if (!single_pred_p (bb1) |
439 | || single_pred (bb1) != bb) | |
33784d89 | 440 | continue; |
20e5647c | 441 | |
e6d0e152 | 442 | if (do_store_elim) |
443 | { | |
444 | /* bb1 is the middle block, bb2 the join block, bb the split block, | |
445 | e1 the fallthrough edge from bb1 to bb2. We can't do the | |
446 | optimization if the join block has more than two predecessors. */ | |
447 | if (EDGE_COUNT (bb2->preds) > 2) | |
448 | continue; | |
449 | if (cond_store_replacement (bb1, bb2, e1, e2, nontrap)) | |
450 | cfgchanged = true; | |
451 | } | |
452 | else | |
453 | { | |
75a70cf9 | 454 | gimple_seq phis = phi_nodes (bb2); |
2109076a | 455 | gimple_stmt_iterator gsi; |
fb9912ea | 456 | bool candorest = true; |
c3597b05 | 457 | |
fb9912ea | 458 | /* Value replacement can work with more than one PHI |
459 | so try that first. */ | |
460 | for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi)) | |
461 | { | |
462 | phi = gsi_stmt (gsi); | |
463 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); | |
464 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
465 | if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2) | |
466 | { | |
467 | candorest = false; | |
468 | cfgchanged = true; | |
469 | break; | |
470 | } | |
471 | } | |
e6d0e152 | 472 | |
fb9912ea | 473 | if (!candorest) |
474 | continue; | |
f32420fb | 475 | |
c3597b05 | 476 | phi = single_non_singleton_phi_for_edges (phis, e1, e2); |
2109076a | 477 | if (!phi) |
e6d0e152 | 478 | continue; |
479 | ||
75a70cf9 | 480 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); |
481 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
e6d0e152 | 482 | |
483 | /* Something is wrong if we cannot find the arguments in the PHI | |
484 | node. */ | |
485 | gcc_assert (arg0 != NULL && arg1 != NULL); | |
486 | ||
487 | /* Do the replacement of conditional if it can be done. */ | |
488 | if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
489 | cfgchanged = true; | |
e6d0e152 | 490 | else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) |
491 | cfgchanged = true; | |
492 | else if (minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
493 | cfgchanged = true; | |
494 | } | |
194899bf | 495 | } |
496 | ||
497 | free (bb_order); | |
48e1416a | 498 | |
e6d0e152 | 499 | if (do_store_elim) |
500 | pointer_set_destroy (nontrap); | |
501 | /* If the CFG has changed, we should cleanup the CFG. */ | |
502 | if (cfgchanged && do_store_elim) | |
503 | { | |
504 | /* In cond-store replacement we have added some loads on edges | |
505 | and new VOPS (as we moved the store, and created a load). */ | |
75a70cf9 | 506 | gsi_commit_edge_inserts (); |
e6d0e152 | 507 | return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals; |
508 | } | |
509 | else if (cfgchanged) | |
510 | return TODO_cleanup_cfg; | |
511 | return 0; | |
194899bf | 512 | } |
513 | ||
fccee353 | 514 | /* Replace PHI node element whose edge is E in block BB with variable NEW. |
33784d89 | 515 | Remove the edge from COND_BLOCK which does not lead to BB (COND_BLOCK |
902929aa | 516 | is known to have two edges, one of which must reach BB). */ |
517 | ||
518 | static void | |
a4844041 | 519 | replace_phi_edge_with_variable (basic_block cond_block, |
75a70cf9 | 520 | edge e, gimple phi, tree new_tree) |
902929aa | 521 | { |
75a70cf9 | 522 | basic_block bb = gimple_bb (phi); |
0e1a77e1 | 523 | basic_block block_to_remove; |
75a70cf9 | 524 | gimple_stmt_iterator gsi; |
33784d89 | 525 | |
20e5647c | 526 | /* Change the PHI argument to new. */ |
f0d6e81c | 527 | SET_USE (PHI_ARG_DEF_PTR (phi, e->dest_idx), new_tree); |
0e1a77e1 | 528 | |
0e1a77e1 | 529 | /* Remove the empty basic block. */ |
cd665a06 | 530 | if (EDGE_SUCC (cond_block, 0)->dest == bb) |
902929aa | 531 | { |
cd665a06 | 532 | EDGE_SUCC (cond_block, 0)->flags |= EDGE_FALLTHRU; |
533 | EDGE_SUCC (cond_block, 0)->flags &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); | |
81c5be57 | 534 | EDGE_SUCC (cond_block, 0)->probability = REG_BR_PROB_BASE; |
535 | EDGE_SUCC (cond_block, 0)->count += EDGE_SUCC (cond_block, 1)->count; | |
0e1a77e1 | 536 | |
cd665a06 | 537 | block_to_remove = EDGE_SUCC (cond_block, 1)->dest; |
902929aa | 538 | } |
539 | else | |
540 | { | |
cd665a06 | 541 | EDGE_SUCC (cond_block, 1)->flags |= EDGE_FALLTHRU; |
542 | EDGE_SUCC (cond_block, 1)->flags | |
902929aa | 543 | &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); |
81c5be57 | 544 | EDGE_SUCC (cond_block, 1)->probability = REG_BR_PROB_BASE; |
545 | EDGE_SUCC (cond_block, 1)->count += EDGE_SUCC (cond_block, 0)->count; | |
0e1a77e1 | 546 | |
cd665a06 | 547 | block_to_remove = EDGE_SUCC (cond_block, 0)->dest; |
902929aa | 548 | } |
0e1a77e1 | 549 | delete_basic_block (block_to_remove); |
20e5647c | 550 | |
902929aa | 551 | /* Eliminate the COND_EXPR at the end of COND_BLOCK. */ |
75a70cf9 | 552 | gsi = gsi_last_bb (cond_block); |
553 | gsi_remove (&gsi, true); | |
20e5647c | 554 | |
902929aa | 555 | if (dump_file && (dump_flags & TDF_DETAILS)) |
556 | fprintf (dump_file, | |
557 | "COND_EXPR in block %d and PHI in block %d converted to straightline code.\n", | |
558 | cond_block->index, | |
559 | bb->index); | |
560 | } | |
561 | ||
562 | /* The function conditional_replacement does the main work of doing the | |
563 | conditional replacement. Return true if the replacement is done. | |
564 | Otherwise return false. | |
565 | BB is the basic block where the replacement is going to be done on. ARG0 | |
dac49aa5 | 566 | is argument 0 from PHI. Likewise for ARG1. */ |
902929aa | 567 | |
568 | static bool | |
33784d89 | 569 | conditional_replacement (basic_block cond_bb, basic_block middle_bb, |
75a70cf9 | 570 | edge e0, edge e1, gimple phi, |
33784d89 | 571 | tree arg0, tree arg1) |
902929aa | 572 | { |
573 | tree result; | |
75a70cf9 | 574 | gimple stmt, new_stmt; |
575 | tree cond; | |
576 | gimple_stmt_iterator gsi; | |
902929aa | 577 | edge true_edge, false_edge; |
75a70cf9 | 578 | tree new_var, new_var2; |
678919fd | 579 | bool neg; |
902929aa | 580 | |
435e1a75 | 581 | /* FIXME: Gimplification of complex type is too hard for now. */ |
47b88316 | 582 | /* We aren't prepared to handle vectors either (and it is a question |
583 | if it would be worthwhile anyway). */ | |
584 | if (!(INTEGRAL_TYPE_P (TREE_TYPE (arg0)) | |
585 | || POINTER_TYPE_P (TREE_TYPE (arg0))) | |
586 | || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
587 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) | |
435e1a75 | 588 | return false; |
589 | ||
678919fd | 590 | /* The PHI arguments have the constants 0 and 1, or 0 and -1, then |
591 | convert it to the conditional. */ | |
902929aa | 592 | if ((integer_zerop (arg0) && integer_onep (arg1)) |
593 | || (integer_zerop (arg1) && integer_onep (arg0))) | |
678919fd | 594 | neg = false; |
595 | else if ((integer_zerop (arg0) && integer_all_onesp (arg1)) | |
596 | || (integer_zerop (arg1) && integer_all_onesp (arg0))) | |
597 | neg = true; | |
902929aa | 598 | else |
599 | return false; | |
20e5647c | 600 | |
33784d89 | 601 | if (!empty_block_p (middle_bb)) |
902929aa | 602 | return false; |
20e5647c | 603 | |
75a70cf9 | 604 | /* At this point we know we have a GIMPLE_COND with two successors. |
2ab0a163 | 605 | One successor is BB, the other successor is an empty block which |
606 | falls through into BB. | |
20e5647c | 607 | |
2ab0a163 | 608 | There is a single PHI node at the join point (BB) and its arguments |
678919fd | 609 | are constants (0, 1) or (0, -1). |
20e5647c | 610 | |
2ab0a163 | 611 | So, given the condition COND, and the two PHI arguments, we can |
20e5647c | 612 | rewrite this PHI into non-branching code: |
613 | ||
2ab0a163 | 614 | dest = (COND) or dest = COND' |
20e5647c | 615 | |
2ab0a163 | 616 | We use the condition as-is if the argument associated with the |
617 | true edge has the value one or the argument associated with the | |
618 | false edge as the value zero. Note that those conditions are not | |
75a70cf9 | 619 | the same since only one of the outgoing edges from the GIMPLE_COND |
2ab0a163 | 620 | will directly reach BB and thus be associated with an argument. */ |
ae5a4794 | 621 | |
75a70cf9 | 622 | stmt = last_stmt (cond_bb); |
623 | result = PHI_RESULT (phi); | |
b2a02a0e | 624 | |
75a70cf9 | 625 | /* To handle special cases like floating point comparison, it is easier and |
626 | less error-prone to build a tree and gimplify it on the fly though it is | |
627 | less efficient. */ | |
6f9714b3 | 628 | cond = fold_build2_loc (gimple_location (stmt), |
629 | gimple_cond_code (stmt), boolean_type_node, | |
630 | gimple_cond_lhs (stmt), gimple_cond_rhs (stmt)); | |
4ee9c684 | 631 | |
75a70cf9 | 632 | /* We need to know which is the true edge and which is the false |
633 | edge so that we know when to invert the condition below. */ | |
634 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
635 | if ((e0 == true_edge && integer_zerop (arg0)) | |
678919fd | 636 | || (e0 == false_edge && !integer_zerop (arg0)) |
75a70cf9 | 637 | || (e1 == true_edge && integer_zerop (arg1)) |
678919fd | 638 | || (e1 == false_edge && !integer_zerop (arg1))) |
6f9714b3 | 639 | cond = fold_build1_loc (gimple_location (stmt), |
678919fd | 640 | TRUTH_NOT_EXPR, TREE_TYPE (cond), cond); |
641 | ||
642 | if (neg) | |
643 | { | |
644 | cond = fold_convert_loc (gimple_location (stmt), | |
645 | TREE_TYPE (result), cond); | |
646 | cond = fold_build1_loc (gimple_location (stmt), | |
647 | NEGATE_EXPR, TREE_TYPE (cond), cond); | |
648 | } | |
75a70cf9 | 649 | |
650 | /* Insert our new statements at the end of conditional block before the | |
651 | COND_STMT. */ | |
652 | gsi = gsi_for_stmt (stmt); | |
653 | new_var = force_gimple_operand_gsi (&gsi, cond, true, NULL, true, | |
654 | GSI_SAME_STMT); | |
655 | ||
656 | if (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (new_var))) | |
657 | { | |
efbcb6de | 658 | source_location locus_0, locus_1; |
659 | ||
03d37e4e | 660 | new_var2 = make_ssa_name (TREE_TYPE (result), NULL); |
75a70cf9 | 661 | new_stmt = gimple_build_assign_with_ops (CONVERT_EXPR, new_var2, |
662 | new_var, NULL); | |
75a70cf9 | 663 | gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); |
664 | new_var = new_var2; | |
efbcb6de | 665 | |
666 | /* Set the locus to the first argument, unless is doesn't have one. */ | |
667 | locus_0 = gimple_phi_arg_location (phi, 0); | |
668 | locus_1 = gimple_phi_arg_location (phi, 1); | |
669 | if (locus_0 == UNKNOWN_LOCATION) | |
670 | locus_0 = locus_1; | |
671 | gimple_set_location (new_stmt, locus_0); | |
4ee9c684 | 672 | } |
20e5647c | 673 | |
75a70cf9 | 674 | replace_phi_edge_with_variable (cond_bb, e1, phi, new_var); |
902929aa | 675 | |
4ee9c684 | 676 | /* Note that we optimized this PHI. */ |
677 | return true; | |
678 | } | |
679 | ||
17b9476e | 680 | /* Update *ARG which is defined in STMT so that it contains the |
681 | computed value if that seems profitable. Return true if the | |
682 | statement is made dead by that rewriting. */ | |
683 | ||
684 | static bool | |
685 | jump_function_from_stmt (tree *arg, gimple stmt) | |
686 | { | |
687 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
688 | if (code == ADDR_EXPR) | |
689 | { | |
690 | /* For arg = &p->i transform it to p, if possible. */ | |
691 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
692 | HOST_WIDE_INT offset; | |
693 | tree tem = get_addr_base_and_unit_offset (TREE_OPERAND (rhs1, 0), | |
694 | &offset); | |
695 | if (tem | |
696 | && TREE_CODE (tem) == MEM_REF | |
cf8f0e63 | 697 | && (mem_ref_offset (tem) + double_int::from_shwi (offset)).is_zero ()) |
17b9476e | 698 | { |
699 | *arg = TREE_OPERAND (tem, 0); | |
700 | return true; | |
701 | } | |
702 | } | |
703 | /* TODO: Much like IPA-CP jump-functions we want to handle constant | |
704 | additions symbolically here, and we'd need to update the comparison | |
705 | code that compares the arg + cst tuples in our caller. For now the | |
706 | code above exactly handles the VEC_BASE pattern from vec.h. */ | |
707 | return false; | |
708 | } | |
709 | ||
f32420fb | 710 | /* RHS is a source argument in a BIT_AND_EXPR which feeds a conditional |
711 | of the form SSA_NAME NE 0. | |
712 | ||
713 | If RHS is fed by a simple EQ_EXPR comparison of two values, see if | |
714 | the two input values of the EQ_EXPR match arg0 and arg1. | |
715 | ||
716 | If so update *code and return TRUE. Otherwise return FALSE. */ | |
717 | ||
718 | static bool | |
719 | rhs_is_fed_for_value_replacement (const_tree arg0, const_tree arg1, | |
720 | enum tree_code *code, const_tree rhs) | |
721 | { | |
722 | /* Obviously if RHS is not an SSA_NAME, we can't look at the defining | |
723 | statement. */ | |
724 | if (TREE_CODE (rhs) == SSA_NAME) | |
725 | { | |
726 | gimple def1 = SSA_NAME_DEF_STMT (rhs); | |
727 | ||
728 | /* Verify the defining statement has an EQ_EXPR on the RHS. */ | |
729 | if (is_gimple_assign (def1) && gimple_assign_rhs_code (def1) == EQ_EXPR) | |
730 | { | |
731 | /* Finally verify the source operands of the EQ_EXPR are equal | |
732 | to arg0 and arg1. */ | |
733 | tree op0 = gimple_assign_rhs1 (def1); | |
734 | tree op1 = gimple_assign_rhs2 (def1); | |
735 | if ((operand_equal_for_phi_arg_p (arg0, op0) | |
736 | && operand_equal_for_phi_arg_p (arg1, op1)) | |
737 | || (operand_equal_for_phi_arg_p (arg0, op1) | |
738 | && operand_equal_for_phi_arg_p (arg1, op0))) | |
739 | { | |
740 | /* We will perform the optimization. */ | |
741 | *code = gimple_assign_rhs_code (def1); | |
742 | return true; | |
743 | } | |
744 | } | |
745 | } | |
746 | return false; | |
747 | } | |
748 | ||
749 | /* Return TRUE if arg0/arg1 are equal to the rhs/lhs or lhs/rhs of COND. | |
750 | ||
751 | Also return TRUE if arg0/arg1 are equal to the source arguments of a | |
752 | an EQ comparison feeding a BIT_AND_EXPR which feeds COND. | |
753 | ||
754 | Return FALSE otherwise. */ | |
755 | ||
756 | static bool | |
757 | operand_equal_for_value_replacement (const_tree arg0, const_tree arg1, | |
758 | enum tree_code *code, gimple cond) | |
759 | { | |
760 | gimple def; | |
761 | tree lhs = gimple_cond_lhs (cond); | |
762 | tree rhs = gimple_cond_rhs (cond); | |
763 | ||
764 | if ((operand_equal_for_phi_arg_p (arg0, lhs) | |
765 | && operand_equal_for_phi_arg_p (arg1, rhs)) | |
766 | || (operand_equal_for_phi_arg_p (arg1, lhs) | |
767 | && operand_equal_for_phi_arg_p (arg0, rhs))) | |
768 | return true; | |
769 | ||
770 | /* Now handle more complex case where we have an EQ comparison | |
771 | which feeds a BIT_AND_EXPR which feeds COND. | |
772 | ||
773 | First verify that COND is of the form SSA_NAME NE 0. */ | |
774 | if (*code != NE_EXPR || !integer_zerop (rhs) | |
775 | || TREE_CODE (lhs) != SSA_NAME) | |
776 | return false; | |
777 | ||
778 | /* Now ensure that SSA_NAME is set by a BIT_AND_EXPR. */ | |
779 | def = SSA_NAME_DEF_STMT (lhs); | |
780 | if (!is_gimple_assign (def) || gimple_assign_rhs_code (def) != BIT_AND_EXPR) | |
781 | return false; | |
782 | ||
783 | /* Now verify arg0/arg1 correspond to the source arguments of an | |
784 | EQ comparison feeding the BIT_AND_EXPR. */ | |
785 | ||
786 | tree tmp = gimple_assign_rhs1 (def); | |
787 | if (rhs_is_fed_for_value_replacement (arg0, arg1, code, tmp)) | |
788 | return true; | |
789 | ||
790 | tmp = gimple_assign_rhs2 (def); | |
791 | if (rhs_is_fed_for_value_replacement (arg0, arg1, code, tmp)) | |
792 | return true; | |
793 | ||
794 | return false; | |
795 | } | |
796 | ||
0beac6fc | 797 | /* The function value_replacement does the main work of doing the value |
fb9912ea | 798 | replacement. Return non-zero if the replacement is done. Otherwise return |
799 | 0. If we remove the middle basic block, return 2. | |
0beac6fc | 800 | BB is the basic block where the replacement is going to be done on. ARG0 |
dac49aa5 | 801 | is argument 0 from the PHI. Likewise for ARG1. */ |
0beac6fc | 802 | |
fb9912ea | 803 | static int |
33784d89 | 804 | value_replacement (basic_block cond_bb, basic_block middle_bb, |
75a70cf9 | 805 | edge e0, edge e1, gimple phi, |
33784d89 | 806 | tree arg0, tree arg1) |
0beac6fc | 807 | { |
17b9476e | 808 | gimple_stmt_iterator gsi; |
75a70cf9 | 809 | gimple cond; |
0beac6fc | 810 | edge true_edge, false_edge; |
75a70cf9 | 811 | enum tree_code code; |
fb9912ea | 812 | bool emtpy_or_with_defined_p = true; |
0beac6fc | 813 | |
814 | /* If the type says honor signed zeros we cannot do this | |
dac49aa5 | 815 | optimization. */ |
0beac6fc | 816 | if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) |
fb9912ea | 817 | return 0; |
0beac6fc | 818 | |
fb9912ea | 819 | /* If there is a statement in MIDDLE_BB that defines one of the PHI |
820 | arguments, then adjust arg0 or arg1. */ | |
17b9476e | 821 | gsi = gsi_after_labels (middle_bb); |
fb9912ea | 822 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) |
823 | gsi_next_nondebug (&gsi); | |
824 | while (!gsi_end_p (gsi)) | |
17b9476e | 825 | { |
fb9912ea | 826 | gimple stmt = gsi_stmt (gsi); |
827 | tree lhs; | |
828 | gsi_next_nondebug (&gsi); | |
829 | if (!is_gimple_assign (stmt)) | |
17b9476e | 830 | { |
fb9912ea | 831 | emtpy_or_with_defined_p = false; |
832 | continue; | |
17b9476e | 833 | } |
fb9912ea | 834 | /* Now try to adjust arg0 or arg1 according to the computation |
835 | in the statement. */ | |
836 | lhs = gimple_assign_lhs (stmt); | |
837 | if (!(lhs == arg0 | |
838 | && jump_function_from_stmt (&arg0, stmt)) | |
839 | || (lhs == arg1 | |
840 | && jump_function_from_stmt (&arg1, stmt))) | |
841 | emtpy_or_with_defined_p = false; | |
17b9476e | 842 | } |
0beac6fc | 843 | |
75a70cf9 | 844 | cond = last_stmt (cond_bb); |
845 | code = gimple_cond_code (cond); | |
0beac6fc | 846 | |
847 | /* This transformation is only valid for equality comparisons. */ | |
75a70cf9 | 848 | if (code != NE_EXPR && code != EQ_EXPR) |
fb9912ea | 849 | return 0; |
0beac6fc | 850 | |
851 | /* We need to know which is the true edge and which is the false | |
852 | edge so that we know if have abs or negative abs. */ | |
33784d89 | 853 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
0beac6fc | 854 | |
855 | /* At this point we know we have a COND_EXPR with two successors. | |
856 | One successor is BB, the other successor is an empty block which | |
857 | falls through into BB. | |
858 | ||
859 | The condition for the COND_EXPR is known to be NE_EXPR or EQ_EXPR. | |
860 | ||
861 | There is a single PHI node at the join point (BB) with two arguments. | |
862 | ||
863 | We now need to verify that the two arguments in the PHI node match | |
864 | the two arguments to the equality comparison. */ | |
20e5647c | 865 | |
f32420fb | 866 | if (operand_equal_for_value_replacement (arg0, arg1, &code, cond)) |
0beac6fc | 867 | { |
868 | edge e; | |
869 | tree arg; | |
870 | ||
50737d20 | 871 | /* For NE_EXPR, we want to build an assignment result = arg where |
872 | arg is the PHI argument associated with the true edge. For | |
873 | EQ_EXPR we want the PHI argument associated with the false edge. */ | |
75a70cf9 | 874 | e = (code == NE_EXPR ? true_edge : false_edge); |
50737d20 | 875 | |
876 | /* Unfortunately, E may not reach BB (it may instead have gone to | |
877 | OTHER_BLOCK). If that is the case, then we want the single outgoing | |
878 | edge from OTHER_BLOCK which reaches BB and represents the desired | |
879 | path from COND_BLOCK. */ | |
33784d89 | 880 | if (e->dest == middle_bb) |
ea091dfd | 881 | e = single_succ_edge (e->dest); |
50737d20 | 882 | |
883 | /* Now we know the incoming edge to BB that has the argument for the | |
884 | RHS of our new assignment statement. */ | |
33784d89 | 885 | if (e0 == e) |
0beac6fc | 886 | arg = arg0; |
887 | else | |
888 | arg = arg1; | |
889 | ||
fb9912ea | 890 | /* If the middle basic block was empty or is defining the |
c3597b05 | 891 | PHI arguments and this is a single phi where the args are different |
892 | for the edges e0 and e1 then we can remove the middle basic block. */ | |
fb9912ea | 893 | if (emtpy_or_with_defined_p |
c3597b05 | 894 | && single_non_singleton_phi_for_edges (phi_nodes (gimple_bb (phi)), |
895 | e0, e1)) | |
fb9912ea | 896 | { |
897 | replace_phi_edge_with_variable (cond_bb, e1, phi, arg); | |
898 | /* Note that we optimized this PHI. */ | |
899 | return 2; | |
900 | } | |
901 | else | |
902 | { | |
903 | /* Replace the PHI arguments with arg. */ | |
904 | SET_PHI_ARG_DEF (phi, e0->dest_idx, arg); | |
905 | SET_PHI_ARG_DEF (phi, e1->dest_idx, arg); | |
906 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
907 | { | |
908 | fprintf (dump_file, "PHI "); | |
909 | print_generic_expr (dump_file, gimple_phi_result (phi), 0); | |
c3597b05 | 910 | fprintf (dump_file, " reduced for COND_EXPR in block %d to ", |
911 | cond_bb->index); | |
fb9912ea | 912 | print_generic_expr (dump_file, arg, 0); |
913 | fprintf (dump_file, ".\n"); | |
914 | } | |
915 | return 1; | |
916 | } | |
0beac6fc | 917 | |
0beac6fc | 918 | } |
fb9912ea | 919 | return 0; |
0beac6fc | 920 | } |
921 | ||
194899bf | 922 | /* The function minmax_replacement does the main work of doing the minmax |
923 | replacement. Return true if the replacement is done. Otherwise return | |
924 | false. | |
925 | BB is the basic block where the replacement is going to be done on. ARG0 | |
926 | is argument 0 from the PHI. Likewise for ARG1. */ | |
927 | ||
928 | static bool | |
929 | minmax_replacement (basic_block cond_bb, basic_block middle_bb, | |
75a70cf9 | 930 | edge e0, edge e1, gimple phi, |
194899bf | 931 | tree arg0, tree arg1) |
932 | { | |
933 | tree result, type; | |
75a70cf9 | 934 | gimple cond, new_stmt; |
194899bf | 935 | edge true_edge, false_edge; |
936 | enum tree_code cmp, minmax, ass_code; | |
937 | tree smaller, larger, arg_true, arg_false; | |
75a70cf9 | 938 | gimple_stmt_iterator gsi, gsi_from; |
194899bf | 939 | |
940 | type = TREE_TYPE (PHI_RESULT (phi)); | |
941 | ||
942 | /* The optimization may be unsafe due to NaNs. */ | |
943 | if (HONOR_NANS (TYPE_MODE (type))) | |
944 | return false; | |
945 | ||
75a70cf9 | 946 | cond = last_stmt (cond_bb); |
947 | cmp = gimple_cond_code (cond); | |
194899bf | 948 | |
949 | /* This transformation is only valid for order comparisons. Record which | |
950 | operand is smaller/larger if the result of the comparison is true. */ | |
951 | if (cmp == LT_EXPR || cmp == LE_EXPR) | |
952 | { | |
75a70cf9 | 953 | smaller = gimple_cond_lhs (cond); |
954 | larger = gimple_cond_rhs (cond); | |
194899bf | 955 | } |
956 | else if (cmp == GT_EXPR || cmp == GE_EXPR) | |
957 | { | |
75a70cf9 | 958 | smaller = gimple_cond_rhs (cond); |
959 | larger = gimple_cond_lhs (cond); | |
194899bf | 960 | } |
961 | else | |
962 | return false; | |
963 | ||
964 | /* We need to know which is the true edge and which is the false | |
965 | edge so that we know if have abs or negative abs. */ | |
966 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
967 | ||
968 | /* Forward the edges over the middle basic block. */ | |
969 | if (true_edge->dest == middle_bb) | |
970 | true_edge = EDGE_SUCC (true_edge->dest, 0); | |
971 | if (false_edge->dest == middle_bb) | |
972 | false_edge = EDGE_SUCC (false_edge->dest, 0); | |
973 | ||
974 | if (true_edge == e0) | |
975 | { | |
976 | gcc_assert (false_edge == e1); | |
977 | arg_true = arg0; | |
978 | arg_false = arg1; | |
979 | } | |
980 | else | |
981 | { | |
982 | gcc_assert (false_edge == e0); | |
983 | gcc_assert (true_edge == e1); | |
984 | arg_true = arg1; | |
985 | arg_false = arg0; | |
986 | } | |
987 | ||
988 | if (empty_block_p (middle_bb)) | |
989 | { | |
990 | if (operand_equal_for_phi_arg_p (arg_true, smaller) | |
991 | && operand_equal_for_phi_arg_p (arg_false, larger)) | |
992 | { | |
993 | /* Case | |
48e1416a | 994 | |
194899bf | 995 | if (smaller < larger) |
996 | rslt = smaller; | |
997 | else | |
998 | rslt = larger; */ | |
999 | minmax = MIN_EXPR; | |
1000 | } | |
1001 | else if (operand_equal_for_phi_arg_p (arg_false, smaller) | |
1002 | && operand_equal_for_phi_arg_p (arg_true, larger)) | |
1003 | minmax = MAX_EXPR; | |
1004 | else | |
1005 | return false; | |
1006 | } | |
1007 | else | |
1008 | { | |
1009 | /* Recognize the following case, assuming d <= u: | |
1010 | ||
1011 | if (a <= u) | |
1012 | b = MAX (a, d); | |
1013 | x = PHI <b, u> | |
1014 | ||
1015 | This is equivalent to | |
1016 | ||
1017 | b = MAX (a, d); | |
1018 | x = MIN (b, u); */ | |
1019 | ||
75a70cf9 | 1020 | gimple assign = last_and_only_stmt (middle_bb); |
1021 | tree lhs, op0, op1, bound; | |
194899bf | 1022 | |
1023 | if (!assign | |
75a70cf9 | 1024 | || gimple_code (assign) != GIMPLE_ASSIGN) |
194899bf | 1025 | return false; |
1026 | ||
75a70cf9 | 1027 | lhs = gimple_assign_lhs (assign); |
1028 | ass_code = gimple_assign_rhs_code (assign); | |
194899bf | 1029 | if (ass_code != MAX_EXPR && ass_code != MIN_EXPR) |
1030 | return false; | |
75a70cf9 | 1031 | op0 = gimple_assign_rhs1 (assign); |
1032 | op1 = gimple_assign_rhs2 (assign); | |
194899bf | 1033 | |
1034 | if (true_edge->src == middle_bb) | |
1035 | { | |
1036 | /* We got here if the condition is true, i.e., SMALLER < LARGER. */ | |
1037 | if (!operand_equal_for_phi_arg_p (lhs, arg_true)) | |
1038 | return false; | |
1039 | ||
1040 | if (operand_equal_for_phi_arg_p (arg_false, larger)) | |
1041 | { | |
1042 | /* Case | |
1043 | ||
1044 | if (smaller < larger) | |
1045 | { | |
1046 | r' = MAX_EXPR (smaller, bound) | |
1047 | } | |
1048 | r = PHI <r', larger> --> to be turned to MIN_EXPR. */ | |
1049 | if (ass_code != MAX_EXPR) | |
1050 | return false; | |
1051 | ||
1052 | minmax = MIN_EXPR; | |
1053 | if (operand_equal_for_phi_arg_p (op0, smaller)) | |
1054 | bound = op1; | |
1055 | else if (operand_equal_for_phi_arg_p (op1, smaller)) | |
1056 | bound = op0; | |
1057 | else | |
1058 | return false; | |
1059 | ||
1060 | /* We need BOUND <= LARGER. */ | |
49d00087 | 1061 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
1062 | bound, larger))) | |
194899bf | 1063 | return false; |
1064 | } | |
1065 | else if (operand_equal_for_phi_arg_p (arg_false, smaller)) | |
1066 | { | |
1067 | /* Case | |
1068 | ||
1069 | if (smaller < larger) | |
1070 | { | |
1071 | r' = MIN_EXPR (larger, bound) | |
1072 | } | |
1073 | r = PHI <r', smaller> --> to be turned to MAX_EXPR. */ | |
1074 | if (ass_code != MIN_EXPR) | |
1075 | return false; | |
1076 | ||
1077 | minmax = MAX_EXPR; | |
1078 | if (operand_equal_for_phi_arg_p (op0, larger)) | |
1079 | bound = op1; | |
1080 | else if (operand_equal_for_phi_arg_p (op1, larger)) | |
1081 | bound = op0; | |
1082 | else | |
1083 | return false; | |
1084 | ||
1085 | /* We need BOUND >= SMALLER. */ | |
49d00087 | 1086 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1087 | bound, smaller))) | |
194899bf | 1088 | return false; |
1089 | } | |
1090 | else | |
1091 | return false; | |
1092 | } | |
1093 | else | |
1094 | { | |
1095 | /* We got here if the condition is false, i.e., SMALLER > LARGER. */ | |
1096 | if (!operand_equal_for_phi_arg_p (lhs, arg_false)) | |
1097 | return false; | |
1098 | ||
1099 | if (operand_equal_for_phi_arg_p (arg_true, larger)) | |
1100 | { | |
1101 | /* Case | |
1102 | ||
1103 | if (smaller > larger) | |
1104 | { | |
1105 | r' = MIN_EXPR (smaller, bound) | |
1106 | } | |
1107 | r = PHI <r', larger> --> to be turned to MAX_EXPR. */ | |
1108 | if (ass_code != MIN_EXPR) | |
1109 | return false; | |
1110 | ||
1111 | minmax = MAX_EXPR; | |
1112 | if (operand_equal_for_phi_arg_p (op0, smaller)) | |
1113 | bound = op1; | |
1114 | else if (operand_equal_for_phi_arg_p (op1, smaller)) | |
1115 | bound = op0; | |
1116 | else | |
1117 | return false; | |
1118 | ||
1119 | /* We need BOUND >= LARGER. */ | |
49d00087 | 1120 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1121 | bound, larger))) | |
194899bf | 1122 | return false; |
1123 | } | |
1124 | else if (operand_equal_for_phi_arg_p (arg_true, smaller)) | |
1125 | { | |
1126 | /* Case | |
1127 | ||
1128 | if (smaller > larger) | |
1129 | { | |
1130 | r' = MAX_EXPR (larger, bound) | |
1131 | } | |
1132 | r = PHI <r', smaller> --> to be turned to MIN_EXPR. */ | |
1133 | if (ass_code != MAX_EXPR) | |
1134 | return false; | |
1135 | ||
1136 | minmax = MIN_EXPR; | |
1137 | if (operand_equal_for_phi_arg_p (op0, larger)) | |
1138 | bound = op1; | |
1139 | else if (operand_equal_for_phi_arg_p (op1, larger)) | |
1140 | bound = op0; | |
1141 | else | |
1142 | return false; | |
1143 | ||
1144 | /* We need BOUND <= SMALLER. */ | |
49d00087 | 1145 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
1146 | bound, smaller))) | |
194899bf | 1147 | return false; |
1148 | } | |
1149 | else | |
1150 | return false; | |
1151 | } | |
1152 | ||
1153 | /* Move the statement from the middle block. */ | |
75a70cf9 | 1154 | gsi = gsi_last_bb (cond_bb); |
445a6ba5 | 1155 | gsi_from = gsi_last_nondebug_bb (middle_bb); |
75a70cf9 | 1156 | gsi_move_before (&gsi_from, &gsi); |
194899bf | 1157 | } |
1158 | ||
1159 | /* Emit the statement to compute min/max. */ | |
1160 | result = duplicate_ssa_name (PHI_RESULT (phi), NULL); | |
75a70cf9 | 1161 | new_stmt = gimple_build_assign_with_ops (minmax, result, arg0, arg1); |
1162 | gsi = gsi_last_bb (cond_bb); | |
1163 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
194899bf | 1164 | |
a4844041 | 1165 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
194899bf | 1166 | return true; |
1167 | } | |
1168 | ||
70512b93 | 1169 | /* The function absolute_replacement does the main work of doing the absolute |
1170 | replacement. Return true if the replacement is done. Otherwise return | |
1171 | false. | |
1172 | bb is the basic block where the replacement is going to be done on. arg0 | |
f7f07c95 | 1173 | is argument 0 from the phi. Likewise for arg1. */ |
33784d89 | 1174 | |
70512b93 | 1175 | static bool |
33784d89 | 1176 | abs_replacement (basic_block cond_bb, basic_block middle_bb, |
a4844041 | 1177 | edge e0 ATTRIBUTE_UNUSED, edge e1, |
75a70cf9 | 1178 | gimple phi, tree arg0, tree arg1) |
70512b93 | 1179 | { |
1180 | tree result; | |
75a70cf9 | 1181 | gimple new_stmt, cond; |
1182 | gimple_stmt_iterator gsi; | |
70512b93 | 1183 | edge true_edge, false_edge; |
75a70cf9 | 1184 | gimple assign; |
70512b93 | 1185 | edge e; |
194899bf | 1186 | tree rhs, lhs; |
70512b93 | 1187 | bool negate; |
1188 | enum tree_code cond_code; | |
1189 | ||
1190 | /* If the type says honor signed zeros we cannot do this | |
dac49aa5 | 1191 | optimization. */ |
70512b93 | 1192 | if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) |
1193 | return false; | |
1194 | ||
70512b93 | 1195 | /* OTHER_BLOCK must have only one executable statement which must have the |
1196 | form arg0 = -arg1 or arg1 = -arg0. */ | |
70512b93 | 1197 | |
194899bf | 1198 | assign = last_and_only_stmt (middle_bb); |
70512b93 | 1199 | /* If we did not find the proper negation assignment, then we can not |
1200 | optimize. */ | |
1201 | if (assign == NULL) | |
1202 | return false; | |
48e1416a | 1203 | |
194899bf | 1204 | /* If we got here, then we have found the only executable statement |
1205 | in OTHER_BLOCK. If it is anything other than arg = -arg1 or | |
1206 | arg1 = -arg0, then we can not optimize. */ | |
75a70cf9 | 1207 | if (gimple_code (assign) != GIMPLE_ASSIGN) |
194899bf | 1208 | return false; |
1209 | ||
75a70cf9 | 1210 | lhs = gimple_assign_lhs (assign); |
194899bf | 1211 | |
75a70cf9 | 1212 | if (gimple_assign_rhs_code (assign) != NEGATE_EXPR) |
194899bf | 1213 | return false; |
1214 | ||
75a70cf9 | 1215 | rhs = gimple_assign_rhs1 (assign); |
48e1416a | 1216 | |
194899bf | 1217 | /* The assignment has to be arg0 = -arg1 or arg1 = -arg0. */ |
1218 | if (!(lhs == arg0 && rhs == arg1) | |
1219 | && !(lhs == arg1 && rhs == arg0)) | |
1220 | return false; | |
70512b93 | 1221 | |
75a70cf9 | 1222 | cond = last_stmt (cond_bb); |
70512b93 | 1223 | result = PHI_RESULT (phi); |
1224 | ||
1225 | /* Only relationals comparing arg[01] against zero are interesting. */ | |
75a70cf9 | 1226 | cond_code = gimple_cond_code (cond); |
70512b93 | 1227 | if (cond_code != GT_EXPR && cond_code != GE_EXPR |
1228 | && cond_code != LT_EXPR && cond_code != LE_EXPR) | |
1229 | return false; | |
1230 | ||
dac49aa5 | 1231 | /* Make sure the conditional is arg[01] OP y. */ |
75a70cf9 | 1232 | if (gimple_cond_lhs (cond) != rhs) |
70512b93 | 1233 | return false; |
1234 | ||
75a70cf9 | 1235 | if (FLOAT_TYPE_P (TREE_TYPE (gimple_cond_rhs (cond))) |
1236 | ? real_zerop (gimple_cond_rhs (cond)) | |
1237 | : integer_zerop (gimple_cond_rhs (cond))) | |
70512b93 | 1238 | ; |
1239 | else | |
1240 | return false; | |
1241 | ||
1242 | /* We need to know which is the true edge and which is the false | |
1243 | edge so that we know if have abs or negative abs. */ | |
33784d89 | 1244 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
70512b93 | 1245 | |
1246 | /* For GT_EXPR/GE_EXPR, if the true edge goes to OTHER_BLOCK, then we | |
1247 | will need to negate the result. Similarly for LT_EXPR/LE_EXPR if | |
1248 | the false edge goes to OTHER_BLOCK. */ | |
1249 | if (cond_code == GT_EXPR || cond_code == GE_EXPR) | |
1250 | e = true_edge; | |
1251 | else | |
1252 | e = false_edge; | |
20e5647c | 1253 | |
33784d89 | 1254 | if (e->dest == middle_bb) |
70512b93 | 1255 | negate = true; |
1256 | else | |
1257 | negate = false; | |
20e5647c | 1258 | |
33784d89 | 1259 | result = duplicate_ssa_name (result, NULL); |
20e5647c | 1260 | |
70512b93 | 1261 | if (negate) |
03d37e4e | 1262 | lhs = make_ssa_name (TREE_TYPE (result), NULL); |
70512b93 | 1263 | else |
1264 | lhs = result; | |
1265 | ||
dac49aa5 | 1266 | /* Build the modify expression with abs expression. */ |
75a70cf9 | 1267 | new_stmt = gimple_build_assign_with_ops (ABS_EXPR, lhs, rhs, NULL); |
70512b93 | 1268 | |
75a70cf9 | 1269 | gsi = gsi_last_bb (cond_bb); |
1270 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
70512b93 | 1271 | |
1272 | if (negate) | |
1273 | { | |
75a70cf9 | 1274 | /* Get the right GSI. We want to insert after the recently |
70512b93 | 1275 | added ABS_EXPR statement (which we know is the first statement |
1276 | in the block. */ | |
75a70cf9 | 1277 | new_stmt = gimple_build_assign_with_ops (NEGATE_EXPR, result, lhs, NULL); |
70512b93 | 1278 | |
75a70cf9 | 1279 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); |
70512b93 | 1280 | } |
20e5647c | 1281 | |
a4844041 | 1282 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
70512b93 | 1283 | |
1284 | /* Note that we optimized this PHI. */ | |
1285 | return true; | |
1286 | } | |
1287 | ||
e6d0e152 | 1288 | /* Auxiliary functions to determine the set of memory accesses which |
1289 | can't trap because they are preceded by accesses to the same memory | |
182cf5a9 | 1290 | portion. We do that for MEM_REFs, so we only need to track |
e6d0e152 | 1291 | the SSA_NAME of the pointer indirectly referenced. The algorithm |
1292 | simply is a walk over all instructions in dominator order. When | |
182cf5a9 | 1293 | we see an MEM_REF we determine if we've already seen a same |
e6d0e152 | 1294 | ref anywhere up to the root of the dominator tree. If we do the |
af4f74fa | 1295 | current access can't trap. If we don't see any dominating access |
e6d0e152 | 1296 | the current access might trap, but might also make later accesses |
af4f74fa | 1297 | non-trapping, so we remember it. We need to be careful with loads |
1298 | or stores, for instance a load might not trap, while a store would, | |
1299 | so if we see a dominating read access this doesn't mean that a later | |
1300 | write access would not trap. Hence we also need to differentiate the | |
1301 | type of access(es) seen. | |
1302 | ||
1303 | ??? We currently are very conservative and assume that a load might | |
1304 | trap even if a store doesn't (write-only memory). This probably is | |
1305 | overly conservative. */ | |
e6d0e152 | 1306 | |
182cf5a9 | 1307 | /* A hash-table of SSA_NAMEs, and in which basic block an MEM_REF |
e6d0e152 | 1308 | through it was seen, which would constitute a no-trap region for |
1309 | same accesses. */ | |
1310 | struct name_to_bb | |
1311 | { | |
963aee26 | 1312 | unsigned int ssa_name_ver; |
42540642 | 1313 | unsigned int phase; |
963aee26 | 1314 | bool store; |
1315 | HOST_WIDE_INT offset, size; | |
e6d0e152 | 1316 | basic_block bb; |
1317 | }; | |
1318 | ||
d9dd21a8 | 1319 | /* Hashtable helpers. */ |
1320 | ||
1321 | struct ssa_names_hasher : typed_free_remove <name_to_bb> | |
1322 | { | |
1323 | typedef name_to_bb value_type; | |
1324 | typedef name_to_bb compare_type; | |
1325 | static inline hashval_t hash (const value_type *); | |
1326 | static inline bool equal (const value_type *, const compare_type *); | |
1327 | }; | |
e6d0e152 | 1328 | |
42540642 | 1329 | /* Used for quick clearing of the hash-table when we see calls. |
1330 | Hash entries with phase < nt_call_phase are invalid. */ | |
1331 | static unsigned int nt_call_phase; | |
1332 | ||
963aee26 | 1333 | /* The hash function. */ |
d9dd21a8 | 1334 | |
1335 | inline hashval_t | |
1336 | ssa_names_hasher::hash (const value_type *n) | |
e6d0e152 | 1337 | { |
963aee26 | 1338 | return n->ssa_name_ver ^ (((hashval_t) n->store) << 31) |
1339 | ^ (n->offset << 6) ^ (n->size << 3); | |
e6d0e152 | 1340 | } |
1341 | ||
963aee26 | 1342 | /* The equality function of *P1 and *P2. */ |
e6d0e152 | 1343 | |
d9dd21a8 | 1344 | inline bool |
1345 | ssa_names_hasher::equal (const value_type *n1, const compare_type *n2) | |
1346 | { | |
963aee26 | 1347 | return n1->ssa_name_ver == n2->ssa_name_ver |
1348 | && n1->store == n2->store | |
1349 | && n1->offset == n2->offset | |
1350 | && n1->size == n2->size; | |
e6d0e152 | 1351 | } |
1352 | ||
d9dd21a8 | 1353 | /* The hash table for remembering what we've seen. */ |
1354 | static hash_table <ssa_names_hasher> seen_ssa_names; | |
1355 | ||
f0b5f617 | 1356 | /* We see the expression EXP in basic block BB. If it's an interesting |
182cf5a9 | 1357 | expression (an MEM_REF through an SSA_NAME) possibly insert the |
af4f74fa | 1358 | expression into the set NONTRAP or the hash table of seen expressions. |
1359 | STORE is true if this expression is on the LHS, otherwise it's on | |
1360 | the RHS. */ | |
e6d0e152 | 1361 | static void |
af4f74fa | 1362 | add_or_mark_expr (basic_block bb, tree exp, |
1363 | struct pointer_set_t *nontrap, bool store) | |
e6d0e152 | 1364 | { |
963aee26 | 1365 | HOST_WIDE_INT size; |
1366 | ||
182cf5a9 | 1367 | if (TREE_CODE (exp) == MEM_REF |
963aee26 | 1368 | && TREE_CODE (TREE_OPERAND (exp, 0)) == SSA_NAME |
35ec552a | 1369 | && tree_fits_shwi_p (TREE_OPERAND (exp, 1)) |
963aee26 | 1370 | && (size = int_size_in_bytes (TREE_TYPE (exp))) > 0) |
e6d0e152 | 1371 | { |
1372 | tree name = TREE_OPERAND (exp, 0); | |
1373 | struct name_to_bb map; | |
d9dd21a8 | 1374 | name_to_bb **slot; |
af4f74fa | 1375 | struct name_to_bb *n2bb; |
e6d0e152 | 1376 | basic_block found_bb = 0; |
1377 | ||
182cf5a9 | 1378 | /* Try to find the last seen MEM_REF through the same |
e6d0e152 | 1379 | SSA_NAME, which can trap. */ |
963aee26 | 1380 | map.ssa_name_ver = SSA_NAME_VERSION (name); |
42540642 | 1381 | map.phase = 0; |
e6d0e152 | 1382 | map.bb = 0; |
af4f74fa | 1383 | map.store = store; |
fcb97e84 | 1384 | map.offset = tree_to_shwi (TREE_OPERAND (exp, 1)); |
963aee26 | 1385 | map.size = size; |
1386 | ||
d9dd21a8 | 1387 | slot = seen_ssa_names.find_slot (&map, INSERT); |
1388 | n2bb = *slot; | |
42540642 | 1389 | if (n2bb && n2bb->phase >= nt_call_phase) |
af4f74fa | 1390 | found_bb = n2bb->bb; |
e6d0e152 | 1391 | |
182cf5a9 | 1392 | /* If we've found a trapping MEM_REF, _and_ it dominates EXP |
e6d0e152 | 1393 | (it's in a basic block on the path from us to the dominator root) |
1394 | then we can't trap. */ | |
42540642 | 1395 | if (found_bb && (((size_t)found_bb->aux) & 1) == 1) |
e6d0e152 | 1396 | { |
1397 | pointer_set_insert (nontrap, exp); | |
1398 | } | |
1399 | else | |
1400 | { | |
1401 | /* EXP might trap, so insert it into the hash table. */ | |
af4f74fa | 1402 | if (n2bb) |
e6d0e152 | 1403 | { |
42540642 | 1404 | n2bb->phase = nt_call_phase; |
af4f74fa | 1405 | n2bb->bb = bb; |
e6d0e152 | 1406 | } |
1407 | else | |
1408 | { | |
af4f74fa | 1409 | n2bb = XNEW (struct name_to_bb); |
963aee26 | 1410 | n2bb->ssa_name_ver = SSA_NAME_VERSION (name); |
42540642 | 1411 | n2bb->phase = nt_call_phase; |
af4f74fa | 1412 | n2bb->bb = bb; |
1413 | n2bb->store = store; | |
963aee26 | 1414 | n2bb->offset = map.offset; |
1415 | n2bb->size = size; | |
af4f74fa | 1416 | *slot = n2bb; |
e6d0e152 | 1417 | } |
1418 | } | |
1419 | } | |
1420 | } | |
1421 | ||
54c91640 | 1422 | class nontrapping_dom_walker : public dom_walker |
1423 | { | |
1424 | public: | |
1425 | nontrapping_dom_walker (cdi_direction direction, pointer_set_t *ps) | |
ae84f584 | 1426 | : dom_walker (direction), m_nontrapping (ps) {} |
54c91640 | 1427 | |
1428 | virtual void before_dom_children (basic_block); | |
1429 | virtual void after_dom_children (basic_block); | |
1430 | ||
1431 | private: | |
ae84f584 | 1432 | pointer_set_t *m_nontrapping; |
54c91640 | 1433 | }; |
1434 | ||
e6d0e152 | 1435 | /* Called by walk_dominator_tree, when entering the block BB. */ |
54c91640 | 1436 | void |
1437 | nontrapping_dom_walker::before_dom_children (basic_block bb) | |
e6d0e152 | 1438 | { |
42540642 | 1439 | edge e; |
1440 | edge_iterator ei; | |
75a70cf9 | 1441 | gimple_stmt_iterator gsi; |
42540642 | 1442 | |
1443 | /* If we haven't seen all our predecessors, clear the hash-table. */ | |
1444 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1445 | if ((((size_t)e->src->aux) & 2) == 0) | |
1446 | { | |
1447 | nt_call_phase++; | |
1448 | break; | |
1449 | } | |
1450 | ||
1451 | /* Mark this BB as being on the path to dominator root and as visited. */ | |
1452 | bb->aux = (void*)(1 | 2); | |
e6d0e152 | 1453 | |
1454 | /* And walk the statements in order. */ | |
75a70cf9 | 1455 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
e6d0e152 | 1456 | { |
75a70cf9 | 1457 | gimple stmt = gsi_stmt (gsi); |
e6d0e152 | 1458 | |
42540642 | 1459 | if (is_gimple_call (stmt) && !nonfreeing_call_p (stmt)) |
1460 | nt_call_phase++; | |
1461 | else if (gimple_assign_single_p (stmt) && !gimple_has_volatile_ops (stmt)) | |
e6d0e152 | 1462 | { |
ae84f584 | 1463 | add_or_mark_expr (bb, gimple_assign_lhs (stmt), m_nontrapping, true); |
1464 | add_or_mark_expr (bb, gimple_assign_rhs1 (stmt), m_nontrapping, false); | |
e6d0e152 | 1465 | } |
1466 | } | |
1467 | } | |
1468 | ||
1469 | /* Called by walk_dominator_tree, when basic block BB is exited. */ | |
54c91640 | 1470 | void |
1471 | nontrapping_dom_walker::after_dom_children (basic_block bb) | |
e6d0e152 | 1472 | { |
1473 | /* This BB isn't on the path to dominator root anymore. */ | |
42540642 | 1474 | bb->aux = (void*)2; |
e6d0e152 | 1475 | } |
1476 | ||
1477 | /* This is the entry point of gathering non trapping memory accesses. | |
1478 | It will do a dominator walk over the whole function, and it will | |
1479 | make use of the bb->aux pointers. It returns a set of trees | |
182cf5a9 | 1480 | (the MEM_REFs itself) which can't trap. */ |
e6d0e152 | 1481 | static struct pointer_set_t * |
1482 | get_non_trapping (void) | |
1483 | { | |
42540642 | 1484 | nt_call_phase = 0; |
54c91640 | 1485 | pointer_set_t *nontrap = pointer_set_create (); |
d9dd21a8 | 1486 | seen_ssa_names.create (128); |
e6d0e152 | 1487 | /* We're going to do a dominator walk, so ensure that we have |
1488 | dominance information. */ | |
1489 | calculate_dominance_info (CDI_DOMINATORS); | |
1490 | ||
54c91640 | 1491 | nontrapping_dom_walker (CDI_DOMINATORS, nontrap) |
1492 | .walk (cfun->cfg->x_entry_block_ptr); | |
1493 | ||
d9dd21a8 | 1494 | seen_ssa_names.dispose (); |
e6d0e152 | 1495 | |
42540642 | 1496 | clear_aux_for_blocks (); |
e6d0e152 | 1497 | return nontrap; |
1498 | } | |
1499 | ||
1500 | /* Do the main work of conditional store replacement. We already know | |
1501 | that the recognized pattern looks like so: | |
1502 | ||
1503 | split: | |
1504 | if (cond) goto MIDDLE_BB; else goto JOIN_BB (edge E1) | |
1505 | MIDDLE_BB: | |
1506 | something | |
1507 | fallthrough (edge E0) | |
1508 | JOIN_BB: | |
1509 | some more | |
1510 | ||
1511 | We check that MIDDLE_BB contains only one store, that that store | |
1512 | doesn't trap (not via NOTRAP, but via checking if an access to the same | |
1513 | memory location dominates us) and that the store has a "simple" RHS. */ | |
1514 | ||
1515 | static bool | |
1516 | cond_store_replacement (basic_block middle_bb, basic_block join_bb, | |
1517 | edge e0, edge e1, struct pointer_set_t *nontrap) | |
1518 | { | |
75a70cf9 | 1519 | gimple assign = last_and_only_stmt (middle_bb); |
03d37e4e | 1520 | tree lhs, rhs, name, name2; |
75a70cf9 | 1521 | gimple newphi, new_stmt; |
1522 | gimple_stmt_iterator gsi; | |
efbcb6de | 1523 | source_location locus; |
e6d0e152 | 1524 | |
1525 | /* Check if middle_bb contains of only one store. */ | |
1526 | if (!assign | |
6cc085b6 | 1527 | || !gimple_assign_single_p (assign) |
1528 | || gimple_has_volatile_ops (assign)) | |
e6d0e152 | 1529 | return false; |
1530 | ||
efbcb6de | 1531 | locus = gimple_location (assign); |
75a70cf9 | 1532 | lhs = gimple_assign_lhs (assign); |
1533 | rhs = gimple_assign_rhs1 (assign); | |
182cf5a9 | 1534 | if (TREE_CODE (lhs) != MEM_REF |
91cf53d5 | 1535 | || TREE_CODE (TREE_OPERAND (lhs, 0)) != SSA_NAME |
3211fa0a | 1536 | || !is_gimple_reg_type (TREE_TYPE (lhs))) |
e6d0e152 | 1537 | return false; |
91cf53d5 | 1538 | |
e6d0e152 | 1539 | /* Prove that we can move the store down. We could also check |
1540 | TREE_THIS_NOTRAP here, but in that case we also could move stores, | |
1541 | whose value is not available readily, which we want to avoid. */ | |
1542 | if (!pointer_set_contains (nontrap, lhs)) | |
1543 | return false; | |
1544 | ||
1545 | /* Now we've checked the constraints, so do the transformation: | |
1546 | 1) Remove the single store. */ | |
75a70cf9 | 1547 | gsi = gsi_for_stmt (assign); |
3211fa0a | 1548 | unlink_stmt_vdef (assign); |
75a70cf9 | 1549 | gsi_remove (&gsi, true); |
91cf53d5 | 1550 | release_defs (assign); |
e6d0e152 | 1551 | |
03d37e4e | 1552 | /* 2) Insert a load from the memory of the store to the temporary |
e6d0e152 | 1553 | on the edge which did not contain the store. */ |
1554 | lhs = unshare_expr (lhs); | |
03d37e4e | 1555 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1556 | new_stmt = gimple_build_assign (name, lhs); | |
efbcb6de | 1557 | gimple_set_location (new_stmt, locus); |
75a70cf9 | 1558 | gsi_insert_on_edge (e1, new_stmt); |
e6d0e152 | 1559 | |
03d37e4e | 1560 | /* 3) Create a PHI node at the join block, with one argument |
e6d0e152 | 1561 | holding the old RHS, and the other holding the temporary |
1562 | where we stored the old memory contents. */ | |
03d37e4e | 1563 | name2 = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1564 | newphi = create_phi_node (name2, join_bb); | |
60d535d2 | 1565 | add_phi_arg (newphi, rhs, e0, locus); |
1566 | add_phi_arg (newphi, name, e1, locus); | |
e6d0e152 | 1567 | |
1568 | lhs = unshare_expr (lhs); | |
75a70cf9 | 1569 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); |
e6d0e152 | 1570 | |
03d37e4e | 1571 | /* 4) Insert that PHI node. */ |
75a70cf9 | 1572 | gsi = gsi_after_labels (join_bb); |
1573 | if (gsi_end_p (gsi)) | |
e6d0e152 | 1574 | { |
75a70cf9 | 1575 | gsi = gsi_last_bb (join_bb); |
1576 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
e6d0e152 | 1577 | } |
1578 | else | |
75a70cf9 | 1579 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); |
e6d0e152 | 1580 | |
1581 | return true; | |
1582 | } | |
4ee9c684 | 1583 | |
ec611e12 | 1584 | /* Do the main work of conditional store replacement. */ |
91cf53d5 | 1585 | |
1586 | static bool | |
ec611e12 | 1587 | cond_if_else_store_replacement_1 (basic_block then_bb, basic_block else_bb, |
1588 | basic_block join_bb, gimple then_assign, | |
1589 | gimple else_assign) | |
91cf53d5 | 1590 | { |
03d37e4e | 1591 | tree lhs_base, lhs, then_rhs, else_rhs, name; |
91cf53d5 | 1592 | source_location then_locus, else_locus; |
1593 | gimple_stmt_iterator gsi; | |
1594 | gimple newphi, new_stmt; | |
1595 | ||
91cf53d5 | 1596 | if (then_assign == NULL |
1597 | || !gimple_assign_single_p (then_assign) | |
3c25489e | 1598 | || gimple_clobber_p (then_assign) |
6cc085b6 | 1599 | || gimple_has_volatile_ops (then_assign) |
91cf53d5 | 1600 | || else_assign == NULL |
3c25489e | 1601 | || !gimple_assign_single_p (else_assign) |
6cc085b6 | 1602 | || gimple_clobber_p (else_assign) |
1603 | || gimple_has_volatile_ops (else_assign)) | |
91cf53d5 | 1604 | return false; |
1605 | ||
1606 | lhs = gimple_assign_lhs (then_assign); | |
1607 | if (!is_gimple_reg_type (TREE_TYPE (lhs)) | |
1608 | || !operand_equal_p (lhs, gimple_assign_lhs (else_assign), 0)) | |
1609 | return false; | |
1610 | ||
1611 | lhs_base = get_base_address (lhs); | |
1612 | if (lhs_base == NULL_TREE | |
1613 | || (!DECL_P (lhs_base) && TREE_CODE (lhs_base) != MEM_REF)) | |
1614 | return false; | |
1615 | ||
1616 | then_rhs = gimple_assign_rhs1 (then_assign); | |
1617 | else_rhs = gimple_assign_rhs1 (else_assign); | |
1618 | then_locus = gimple_location (then_assign); | |
1619 | else_locus = gimple_location (else_assign); | |
1620 | ||
1621 | /* Now we've checked the constraints, so do the transformation: | |
1622 | 1) Remove the stores. */ | |
1623 | gsi = gsi_for_stmt (then_assign); | |
1624 | unlink_stmt_vdef (then_assign); | |
1625 | gsi_remove (&gsi, true); | |
1626 | release_defs (then_assign); | |
1627 | ||
1628 | gsi = gsi_for_stmt (else_assign); | |
1629 | unlink_stmt_vdef (else_assign); | |
1630 | gsi_remove (&gsi, true); | |
1631 | release_defs (else_assign); | |
1632 | ||
03d37e4e | 1633 | /* 2) Create a PHI node at the join block, with one argument |
91cf53d5 | 1634 | holding the old RHS, and the other holding the temporary |
1635 | where we stored the old memory contents. */ | |
03d37e4e | 1636 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1637 | newphi = create_phi_node (name, join_bb); | |
60d535d2 | 1638 | add_phi_arg (newphi, then_rhs, EDGE_SUCC (then_bb, 0), then_locus); |
1639 | add_phi_arg (newphi, else_rhs, EDGE_SUCC (else_bb, 0), else_locus); | |
91cf53d5 | 1640 | |
1641 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); | |
1642 | ||
03d37e4e | 1643 | /* 3) Insert that PHI node. */ |
91cf53d5 | 1644 | gsi = gsi_after_labels (join_bb); |
1645 | if (gsi_end_p (gsi)) | |
1646 | { | |
1647 | gsi = gsi_last_bb (join_bb); | |
1648 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
1649 | } | |
1650 | else | |
1651 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
1652 | ||
1653 | return true; | |
1654 | } | |
1655 | ||
ec611e12 | 1656 | /* Conditional store replacement. We already know |
1657 | that the recognized pattern looks like so: | |
1658 | ||
1659 | split: | |
1660 | if (cond) goto THEN_BB; else goto ELSE_BB (edge E1) | |
1661 | THEN_BB: | |
1662 | ... | |
1663 | X = Y; | |
1664 | ... | |
1665 | goto JOIN_BB; | |
1666 | ELSE_BB: | |
1667 | ... | |
1668 | X = Z; | |
1669 | ... | |
1670 | fallthrough (edge E0) | |
1671 | JOIN_BB: | |
1672 | some more | |
1673 | ||
1674 | We check that it is safe to sink the store to JOIN_BB by verifying that | |
1675 | there are no read-after-write or write-after-write dependencies in | |
1676 | THEN_BB and ELSE_BB. */ | |
1677 | ||
1678 | static bool | |
1679 | cond_if_else_store_replacement (basic_block then_bb, basic_block else_bb, | |
1680 | basic_block join_bb) | |
1681 | { | |
1682 | gimple then_assign = last_and_only_stmt (then_bb); | |
1683 | gimple else_assign = last_and_only_stmt (else_bb); | |
f1f41a6c | 1684 | vec<data_reference_p> then_datarefs, else_datarefs; |
1685 | vec<ddr_p> then_ddrs, else_ddrs; | |
ec611e12 | 1686 | gimple then_store, else_store; |
1687 | bool found, ok = false, res; | |
1688 | struct data_dependence_relation *ddr; | |
1689 | data_reference_p then_dr, else_dr; | |
1690 | int i, j; | |
1691 | tree then_lhs, else_lhs; | |
ec611e12 | 1692 | basic_block blocks[3]; |
1693 | ||
1694 | if (MAX_STORES_TO_SINK == 0) | |
1695 | return false; | |
1696 | ||
1697 | /* Handle the case with single statement in THEN_BB and ELSE_BB. */ | |
1698 | if (then_assign && else_assign) | |
1699 | return cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, | |
1700 | then_assign, else_assign); | |
1701 | ||
1702 | /* Find data references. */ | |
f1f41a6c | 1703 | then_datarefs.create (1); |
1704 | else_datarefs.create (1); | |
ec611e12 | 1705 | if ((find_data_references_in_bb (NULL, then_bb, &then_datarefs) |
1706 | == chrec_dont_know) | |
f1f41a6c | 1707 | || !then_datarefs.length () |
ec611e12 | 1708 | || (find_data_references_in_bb (NULL, else_bb, &else_datarefs) |
1709 | == chrec_dont_know) | |
f1f41a6c | 1710 | || !else_datarefs.length ()) |
ec611e12 | 1711 | { |
1712 | free_data_refs (then_datarefs); | |
1713 | free_data_refs (else_datarefs); | |
1714 | return false; | |
1715 | } | |
1716 | ||
1717 | /* Find pairs of stores with equal LHS. */ | |
e85cf4e5 | 1718 | stack_vec<gimple, 1> then_stores, else_stores; |
f1f41a6c | 1719 | FOR_EACH_VEC_ELT (then_datarefs, i, then_dr) |
ec611e12 | 1720 | { |
1721 | if (DR_IS_READ (then_dr)) | |
1722 | continue; | |
1723 | ||
1724 | then_store = DR_STMT (then_dr); | |
728dcc71 | 1725 | then_lhs = gimple_get_lhs (then_store); |
ec611e12 | 1726 | found = false; |
1727 | ||
f1f41a6c | 1728 | FOR_EACH_VEC_ELT (else_datarefs, j, else_dr) |
ec611e12 | 1729 | { |
1730 | if (DR_IS_READ (else_dr)) | |
1731 | continue; | |
1732 | ||
1733 | else_store = DR_STMT (else_dr); | |
728dcc71 | 1734 | else_lhs = gimple_get_lhs (else_store); |
ec611e12 | 1735 | |
1736 | if (operand_equal_p (then_lhs, else_lhs, 0)) | |
1737 | { | |
1738 | found = true; | |
1739 | break; | |
1740 | } | |
1741 | } | |
1742 | ||
1743 | if (!found) | |
1744 | continue; | |
1745 | ||
f1f41a6c | 1746 | then_stores.safe_push (then_store); |
1747 | else_stores.safe_push (else_store); | |
ec611e12 | 1748 | } |
1749 | ||
1750 | /* No pairs of stores found. */ | |
f1f41a6c | 1751 | if (!then_stores.length () |
1752 | || then_stores.length () > (unsigned) MAX_STORES_TO_SINK) | |
ec611e12 | 1753 | { |
1754 | free_data_refs (then_datarefs); | |
1755 | free_data_refs (else_datarefs); | |
ec611e12 | 1756 | return false; |
1757 | } | |
1758 | ||
1759 | /* Compute and check data dependencies in both basic blocks. */ | |
f1f41a6c | 1760 | then_ddrs.create (1); |
1761 | else_ddrs.create (1); | |
1762 | if (!compute_all_dependences (then_datarefs, &then_ddrs, | |
1e094109 | 1763 | vNULL, false) |
f1f41a6c | 1764 | || !compute_all_dependences (else_datarefs, &else_ddrs, |
1e094109 | 1765 | vNULL, false)) |
8b3fb720 | 1766 | { |
1767 | free_dependence_relations (then_ddrs); | |
1768 | free_dependence_relations (else_ddrs); | |
1769 | free_data_refs (then_datarefs); | |
1770 | free_data_refs (else_datarefs); | |
8b3fb720 | 1771 | return false; |
1772 | } | |
ec611e12 | 1773 | blocks[0] = then_bb; |
1774 | blocks[1] = else_bb; | |
1775 | blocks[2] = join_bb; | |
1776 | renumber_gimple_stmt_uids_in_blocks (blocks, 3); | |
1777 | ||
1778 | /* Check that there are no read-after-write or write-after-write dependencies | |
1779 | in THEN_BB. */ | |
f1f41a6c | 1780 | FOR_EACH_VEC_ELT (then_ddrs, i, ddr) |
ec611e12 | 1781 | { |
1782 | struct data_reference *dra = DDR_A (ddr); | |
1783 | struct data_reference *drb = DDR_B (ddr); | |
1784 | ||
1785 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
1786 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
1787 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
1788 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
1789 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
1790 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
1791 | { | |
1792 | free_dependence_relations (then_ddrs); | |
1793 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1794 | free_data_refs (then_datarefs); |
1795 | free_data_refs (else_datarefs); | |
ec611e12 | 1796 | return false; |
1797 | } | |
1798 | } | |
1799 | ||
1800 | /* Check that there are no read-after-write or write-after-write dependencies | |
1801 | in ELSE_BB. */ | |
f1f41a6c | 1802 | FOR_EACH_VEC_ELT (else_ddrs, i, ddr) |
ec611e12 | 1803 | { |
1804 | struct data_reference *dra = DDR_A (ddr); | |
1805 | struct data_reference *drb = DDR_B (ddr); | |
1806 | ||
1807 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
1808 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
1809 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
1810 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
1811 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
1812 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
1813 | { | |
1814 | free_dependence_relations (then_ddrs); | |
1815 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1816 | free_data_refs (then_datarefs); |
1817 | free_data_refs (else_datarefs); | |
ec611e12 | 1818 | return false; |
1819 | } | |
1820 | } | |
1821 | ||
1822 | /* Sink stores with same LHS. */ | |
f1f41a6c | 1823 | FOR_EACH_VEC_ELT (then_stores, i, then_store) |
ec611e12 | 1824 | { |
f1f41a6c | 1825 | else_store = else_stores[i]; |
ec611e12 | 1826 | res = cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, |
1827 | then_store, else_store); | |
1828 | ok = ok || res; | |
1829 | } | |
1830 | ||
1831 | free_dependence_relations (then_ddrs); | |
1832 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1833 | free_data_refs (then_datarefs); |
1834 | free_data_refs (else_datarefs); | |
ec611e12 | 1835 | |
1836 | return ok; | |
1837 | } | |
1838 | ||
239e9670 | 1839 | /* Return TRUE if STMT has a VUSE whose corresponding VDEF is in BB. */ |
1840 | ||
1841 | static bool | |
1842 | local_mem_dependence (gimple stmt, basic_block bb) | |
1843 | { | |
1844 | tree vuse = gimple_vuse (stmt); | |
1845 | gimple def; | |
1846 | ||
1847 | if (!vuse) | |
1848 | return false; | |
1849 | ||
1850 | def = SSA_NAME_DEF_STMT (vuse); | |
1851 | return (def && gimple_bb (def) == bb); | |
1852 | } | |
1853 | ||
1854 | /* Given a "diamond" control-flow pattern where BB0 tests a condition, | |
1855 | BB1 and BB2 are "then" and "else" blocks dependent on this test, | |
f32420fb | 1856 | and BB3 rejoins control flow following BB1 and BB2, look for |
239e9670 | 1857 | opportunities to hoist loads as follows. If BB3 contains a PHI of |
1858 | two loads, one each occurring in BB1 and BB2, and the loads are | |
1859 | provably of adjacent fields in the same structure, then move both | |
1860 | loads into BB0. Of course this can only be done if there are no | |
1861 | dependencies preventing such motion. | |
1862 | ||
1863 | One of the hoisted loads will always be speculative, so the | |
1864 | transformation is currently conservative: | |
1865 | ||
1866 | - The fields must be strictly adjacent. | |
1867 | - The two fields must occupy a single memory block that is | |
1868 | guaranteed to not cross a page boundary. | |
1869 | ||
1870 | The last is difficult to prove, as such memory blocks should be | |
1871 | aligned on the minimum of the stack alignment boundary and the | |
1872 | alignment guaranteed by heap allocation interfaces. Thus we rely | |
1873 | on a parameter for the alignment value. | |
1874 | ||
1875 | Provided a good value is used for the last case, the first | |
1876 | restriction could possibly be relaxed. */ | |
1877 | ||
1878 | static void | |
1879 | hoist_adjacent_loads (basic_block bb0, basic_block bb1, | |
1880 | basic_block bb2, basic_block bb3) | |
1881 | { | |
1882 | int param_align = PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE); | |
1883 | unsigned param_align_bits = (unsigned) (param_align * BITS_PER_UNIT); | |
1884 | gimple_stmt_iterator gsi; | |
1885 | ||
1886 | /* Walk the phis in bb3 looking for an opportunity. We are looking | |
1887 | for phis of two SSA names, one each of which is defined in bb1 and | |
1888 | bb2. */ | |
1889 | for (gsi = gsi_start_phis (bb3); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1890 | { | |
1891 | gimple phi_stmt = gsi_stmt (gsi); | |
1892 | gimple def1, def2, defswap; | |
1893 | tree arg1, arg2, ref1, ref2, field1, field2, fieldswap; | |
1894 | tree tree_offset1, tree_offset2, tree_size2, next; | |
1895 | int offset1, offset2, size2; | |
1896 | unsigned align1; | |
1897 | gimple_stmt_iterator gsi2; | |
1898 | basic_block bb_for_def1, bb_for_def2; | |
1899 | ||
7c782c9b | 1900 | if (gimple_phi_num_args (phi_stmt) != 2 |
1901 | || virtual_operand_p (gimple_phi_result (phi_stmt))) | |
239e9670 | 1902 | continue; |
1903 | ||
1904 | arg1 = gimple_phi_arg_def (phi_stmt, 0); | |
1905 | arg2 = gimple_phi_arg_def (phi_stmt, 1); | |
f32420fb | 1906 | |
239e9670 | 1907 | if (TREE_CODE (arg1) != SSA_NAME |
1908 | || TREE_CODE (arg2) != SSA_NAME | |
1909 | || SSA_NAME_IS_DEFAULT_DEF (arg1) | |
7c782c9b | 1910 | || SSA_NAME_IS_DEFAULT_DEF (arg2)) |
239e9670 | 1911 | continue; |
1912 | ||
1913 | def1 = SSA_NAME_DEF_STMT (arg1); | |
1914 | def2 = SSA_NAME_DEF_STMT (arg2); | |
1915 | ||
1916 | if ((gimple_bb (def1) != bb1 || gimple_bb (def2) != bb2) | |
1917 | && (gimple_bb (def2) != bb1 || gimple_bb (def1) != bb2)) | |
1918 | continue; | |
1919 | ||
1920 | /* Check the mode of the arguments to be sure a conditional move | |
1921 | can be generated for it. */ | |
935611bc | 1922 | if (optab_handler (movcc_optab, TYPE_MODE (TREE_TYPE (arg1))) |
1923 | == CODE_FOR_nothing) | |
239e9670 | 1924 | continue; |
1925 | ||
1926 | /* Both statements must be assignments whose RHS is a COMPONENT_REF. */ | |
1927 | if (!gimple_assign_single_p (def1) | |
6cc085b6 | 1928 | || !gimple_assign_single_p (def2) |
1929 | || gimple_has_volatile_ops (def1) | |
1930 | || gimple_has_volatile_ops (def2)) | |
239e9670 | 1931 | continue; |
1932 | ||
1933 | ref1 = gimple_assign_rhs1 (def1); | |
1934 | ref2 = gimple_assign_rhs1 (def2); | |
1935 | ||
1936 | if (TREE_CODE (ref1) != COMPONENT_REF | |
1937 | || TREE_CODE (ref2) != COMPONENT_REF) | |
1938 | continue; | |
1939 | ||
1940 | /* The zeroth operand of the two component references must be | |
1941 | identical. It is not sufficient to compare get_base_address of | |
1942 | the two references, because this could allow for different | |
1943 | elements of the same array in the two trees. It is not safe to | |
1944 | assume that the existence of one array element implies the | |
1945 | existence of a different one. */ | |
1946 | if (!operand_equal_p (TREE_OPERAND (ref1, 0), TREE_OPERAND (ref2, 0), 0)) | |
1947 | continue; | |
1948 | ||
1949 | field1 = TREE_OPERAND (ref1, 1); | |
1950 | field2 = TREE_OPERAND (ref2, 1); | |
1951 | ||
1952 | /* Check for field adjacency, and ensure field1 comes first. */ | |
1953 | for (next = DECL_CHAIN (field1); | |
1954 | next && TREE_CODE (next) != FIELD_DECL; | |
1955 | next = DECL_CHAIN (next)) | |
1956 | ; | |
1957 | ||
1958 | if (next != field2) | |
1959 | { | |
1960 | for (next = DECL_CHAIN (field2); | |
1961 | next && TREE_CODE (next) != FIELD_DECL; | |
1962 | next = DECL_CHAIN (next)) | |
1963 | ; | |
1964 | ||
1965 | if (next != field1) | |
1966 | continue; | |
1967 | ||
1968 | fieldswap = field1; | |
1969 | field1 = field2; | |
1970 | field2 = fieldswap; | |
1971 | defswap = def1; | |
1972 | def1 = def2; | |
1973 | def2 = defswap; | |
239e9670 | 1974 | } |
1975 | ||
7c74ee50 | 1976 | bb_for_def1 = gimple_bb (def1); |
1977 | bb_for_def2 = gimple_bb (def2); | |
1978 | ||
239e9670 | 1979 | /* Check for proper alignment of the first field. */ |
1980 | tree_offset1 = bit_position (field1); | |
1981 | tree_offset2 = bit_position (field2); | |
1982 | tree_size2 = DECL_SIZE (field2); | |
1983 | ||
cd4547bf | 1984 | if (!tree_fits_uhwi_p (tree_offset1) |
1985 | || !tree_fits_uhwi_p (tree_offset2) | |
1986 | || !tree_fits_uhwi_p (tree_size2)) | |
239e9670 | 1987 | continue; |
1988 | ||
8c53c46c | 1989 | offset1 = tree_to_uhwi (tree_offset1); |
1990 | offset2 = tree_to_uhwi (tree_offset2); | |
1991 | size2 = tree_to_uhwi (tree_size2); | |
239e9670 | 1992 | align1 = DECL_ALIGN (field1) % param_align_bits; |
1993 | ||
1994 | if (offset1 % BITS_PER_UNIT != 0) | |
1995 | continue; | |
1996 | ||
1997 | /* For profitability, the two field references should fit within | |
1998 | a single cache line. */ | |
1999 | if (align1 + offset2 - offset1 + size2 > param_align_bits) | |
2000 | continue; | |
2001 | ||
2002 | /* The two expressions cannot be dependent upon vdefs defined | |
2003 | in bb1/bb2. */ | |
2004 | if (local_mem_dependence (def1, bb_for_def1) | |
2005 | || local_mem_dependence (def2, bb_for_def2)) | |
2006 | continue; | |
2007 | ||
2008 | /* The conditions are satisfied; hoist the loads from bb1 and bb2 into | |
2009 | bb0. We hoist the first one first so that a cache miss is handled | |
2010 | efficiently regardless of hardware cache-fill policy. */ | |
2011 | gsi2 = gsi_for_stmt (def1); | |
2012 | gsi_move_to_bb_end (&gsi2, bb0); | |
2013 | gsi2 = gsi_for_stmt (def2); | |
2014 | gsi_move_to_bb_end (&gsi2, bb0); | |
2015 | ||
2016 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2017 | { | |
2018 | fprintf (dump_file, | |
2019 | "\nHoisting adjacent loads from %d and %d into %d: \n", | |
2020 | bb_for_def1->index, bb_for_def2->index, bb0->index); | |
2021 | print_gimple_stmt (dump_file, def1, 0, TDF_VOPS|TDF_MEMSYMS); | |
2022 | print_gimple_stmt (dump_file, def2, 0, TDF_VOPS|TDF_MEMSYMS); | |
2023 | } | |
2024 | } | |
2025 | } | |
2026 | ||
2027 | /* Determine whether we should attempt to hoist adjacent loads out of | |
2028 | diamond patterns in pass_phiopt. Always hoist loads if | |
2029 | -fhoist-adjacent-loads is specified and the target machine has | |
6f0ddab1 | 2030 | both a conditional move instruction and a defined cache line size. */ |
239e9670 | 2031 | |
2032 | static bool | |
2033 | gate_hoist_loads (void) | |
2034 | { | |
6f0ddab1 | 2035 | return (flag_hoist_adjacent_loads == 1 |
2036 | && PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE) | |
2037 | && HAVE_conditional_move); | |
239e9670 | 2038 | } |
2039 | ||
4ee9c684 | 2040 | /* Always do these optimizations if we have SSA |
20e5647c | 2041 | trees to work on. */ |
4ee9c684 | 2042 | static bool |
2043 | gate_phiopt (void) | |
2044 | { | |
2045 | return 1; | |
2046 | } | |
20e5647c | 2047 | |
cbe8bda8 | 2048 | namespace { |
2049 | ||
2050 | const pass_data pass_data_phiopt = | |
4ee9c684 | 2051 | { |
cbe8bda8 | 2052 | GIMPLE_PASS, /* type */ |
2053 | "phiopt", /* name */ | |
2054 | OPTGROUP_NONE, /* optinfo_flags */ | |
2055 | true, /* has_gate */ | |
2056 | true, /* has_execute */ | |
2057 | TV_TREE_PHIOPT, /* tv_id */ | |
2058 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2059 | 0, /* properties_provided */ | |
2060 | 0, /* properties_destroyed */ | |
2061 | 0, /* todo_flags_start */ | |
2062 | ( TODO_verify_ssa | TODO_verify_flow | |
2063 | | TODO_verify_stmts ), /* todo_flags_finish */ | |
4ee9c684 | 2064 | }; |
e6d0e152 | 2065 | |
cbe8bda8 | 2066 | class pass_phiopt : public gimple_opt_pass |
2067 | { | |
2068 | public: | |
9af5ce0c | 2069 | pass_phiopt (gcc::context *ctxt) |
2070 | : gimple_opt_pass (pass_data_phiopt, ctxt) | |
cbe8bda8 | 2071 | {} |
2072 | ||
2073 | /* opt_pass methods: */ | |
ae84f584 | 2074 | opt_pass * clone () { return new pass_phiopt (m_ctxt); } |
cbe8bda8 | 2075 | bool gate () { return gate_phiopt (); } |
2076 | unsigned int execute () { return tree_ssa_phiopt (); } | |
2077 | ||
2078 | }; // class pass_phiopt | |
2079 | ||
2080 | } // anon namespace | |
2081 | ||
2082 | gimple_opt_pass * | |
2083 | make_pass_phiopt (gcc::context *ctxt) | |
2084 | { | |
2085 | return new pass_phiopt (ctxt); | |
2086 | } | |
2087 | ||
e6d0e152 | 2088 | static bool |
2089 | gate_cselim (void) | |
2090 | { | |
2091 | return flag_tree_cselim; | |
2092 | } | |
2093 | ||
cbe8bda8 | 2094 | namespace { |
2095 | ||
2096 | const pass_data pass_data_cselim = | |
e6d0e152 | 2097 | { |
cbe8bda8 | 2098 | GIMPLE_PASS, /* type */ |
2099 | "cselim", /* name */ | |
2100 | OPTGROUP_NONE, /* optinfo_flags */ | |
2101 | true, /* has_gate */ | |
2102 | true, /* has_execute */ | |
2103 | TV_TREE_PHIOPT, /* tv_id */ | |
2104 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2105 | 0, /* properties_provided */ | |
2106 | 0, /* properties_destroyed */ | |
2107 | 0, /* todo_flags_start */ | |
2108 | ( TODO_verify_ssa | TODO_verify_flow | |
2109 | | TODO_verify_stmts ), /* todo_flags_finish */ | |
e6d0e152 | 2110 | }; |
cbe8bda8 | 2111 | |
2112 | class pass_cselim : public gimple_opt_pass | |
2113 | { | |
2114 | public: | |
9af5ce0c | 2115 | pass_cselim (gcc::context *ctxt) |
2116 | : gimple_opt_pass (pass_data_cselim, ctxt) | |
cbe8bda8 | 2117 | {} |
2118 | ||
2119 | /* opt_pass methods: */ | |
2120 | bool gate () { return gate_cselim (); } | |
2121 | unsigned int execute () { return tree_ssa_cs_elim (); } | |
2122 | ||
2123 | }; // class pass_cselim | |
2124 | ||
2125 | } // anon namespace | |
2126 | ||
2127 | gimple_opt_pass * | |
2128 | make_pass_cselim (gcc::context *ctxt) | |
2129 | { | |
2130 | return new pass_cselim (ctxt); | |
2131 | } |