]>
Commit | Line | Data |
---|---|---|
4ee9c684 | 1 | /* Optimization of PHI nodes by converting them into straightline code. |
963aee26 | 2 | Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 |
91cf53d5 | 3 | Free Software Foundation, Inc. |
4ee9c684 | 4 | |
5 | This file is part of GCC. | |
20e5647c | 6 | |
4ee9c684 | 7 | GCC is free software; you can redistribute it and/or modify it |
8 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 9 | Free Software Foundation; either version 3, or (at your option) any |
4ee9c684 | 10 | later version. |
20e5647c | 11 | |
4ee9c684 | 12 | GCC is distributed in the hope that it will be useful, but WITHOUT |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
20e5647c | 16 | |
4ee9c684 | 17 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 20 | |
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
4ee9c684 | 25 | #include "ggc.h" |
26 | #include "tree.h" | |
0beac6fc | 27 | #include "flags.h" |
4ee9c684 | 28 | #include "tm_p.h" |
29 | #include "basic-block.h" | |
4ee9c684 | 30 | #include "tree-flow.h" |
31 | #include "tree-pass.h" | |
4ee9c684 | 32 | #include "langhooks.h" |
e6d0e152 | 33 | #include "pointer-set.h" |
34 | #include "domwalk.h" | |
ec611e12 | 35 | #include "cfgloop.h" |
36 | #include "tree-data-ref.h" | |
239e9670 | 37 | #include "gimple-pretty-print.h" |
38 | #include "insn-config.h" | |
39 | #include "expr.h" | |
40 | #include "optabs.h" | |
41 | ||
42 | #ifndef HAVE_conditional_move | |
43 | #define HAVE_conditional_move (0) | |
44 | #endif | |
4ee9c684 | 45 | |
75a70cf9 | 46 | static unsigned int tree_ssa_phiopt (void); |
239e9670 | 47 | static unsigned int tree_ssa_phiopt_worker (bool, bool); |
a4844041 | 48 | static bool conditional_replacement (basic_block, basic_block, |
75a70cf9 | 49 | edge, edge, gimple, tree, tree); |
fb9912ea | 50 | static int value_replacement (basic_block, basic_block, |
51 | edge, edge, gimple, tree, tree); | |
a4844041 | 52 | static bool minmax_replacement (basic_block, basic_block, |
75a70cf9 | 53 | edge, edge, gimple, tree, tree); |
a4844041 | 54 | static bool abs_replacement (basic_block, basic_block, |
75a70cf9 | 55 | edge, edge, gimple, tree, tree); |
e6d0e152 | 56 | static bool cond_store_replacement (basic_block, basic_block, edge, edge, |
57 | struct pointer_set_t *); | |
91cf53d5 | 58 | static bool cond_if_else_store_replacement (basic_block, basic_block, basic_block); |
e6d0e152 | 59 | static struct pointer_set_t * get_non_trapping (void); |
75a70cf9 | 60 | static void replace_phi_edge_with_variable (basic_block, edge, gimple, tree); |
239e9670 | 61 | static void hoist_adjacent_loads (basic_block, basic_block, |
62 | basic_block, basic_block); | |
63 | static bool gate_hoist_loads (void); | |
902929aa | 64 | |
caac37c2 | 65 | /* This pass tries to replaces an if-then-else block with an |
66 | assignment. We have four kinds of transformations. Some of these | |
67 | transformations are also performed by the ifcvt RTL optimizer. | |
68 | ||
69 | Conditional Replacement | |
70 | ----------------------- | |
71 | ||
30c5ffd2 | 72 | This transformation, implemented in conditional_replacement, |
caac37c2 | 73 | replaces |
4ee9c684 | 74 | |
75 | bb0: | |
76 | if (cond) goto bb2; else goto bb1; | |
77 | bb1: | |
78 | bb2: | |
caac37c2 | 79 | x = PHI <0 (bb1), 1 (bb0), ...>; |
4ee9c684 | 80 | |
caac37c2 | 81 | with |
20e5647c | 82 | |
2ab0a163 | 83 | bb0: |
caac37c2 | 84 | x' = cond; |
85 | goto bb2; | |
2ab0a163 | 86 | bb2: |
caac37c2 | 87 | x = PHI <x' (bb0), ...>; |
4ee9c684 | 88 | |
caac37c2 | 89 | We remove bb1 as it becomes unreachable. This occurs often due to |
90 | gimplification of conditionals. | |
20e5647c | 91 | |
caac37c2 | 92 | Value Replacement |
93 | ----------------- | |
94 | ||
95 | This transformation, implemented in value_replacement, replaces | |
0beac6fc | 96 | |
97 | bb0: | |
caac37c2 | 98 | if (a != b) goto bb2; else goto bb1; |
0beac6fc | 99 | bb1: |
100 | bb2: | |
caac37c2 | 101 | x = PHI <a (bb1), b (bb0), ...>; |
0beac6fc | 102 | |
caac37c2 | 103 | with |
0beac6fc | 104 | |
105 | bb0: | |
0beac6fc | 106 | bb2: |
caac37c2 | 107 | x = PHI <b (bb0), ...>; |
108 | ||
109 | This opportunity can sometimes occur as a result of other | |
110 | optimizations. | |
0beac6fc | 111 | |
caac37c2 | 112 | ABS Replacement |
113 | --------------- | |
70512b93 | 114 | |
caac37c2 | 115 | This transformation, implemented in abs_replacement, replaces |
70512b93 | 116 | |
117 | bb0: | |
caac37c2 | 118 | if (a >= 0) goto bb2; else goto bb1; |
70512b93 | 119 | bb1: |
caac37c2 | 120 | x = -a; |
70512b93 | 121 | bb2: |
caac37c2 | 122 | x = PHI <x (bb1), a (bb0), ...>; |
70512b93 | 123 | |
caac37c2 | 124 | with |
70512b93 | 125 | |
126 | bb0: | |
caac37c2 | 127 | x' = ABS_EXPR< a >; |
70512b93 | 128 | bb2: |
caac37c2 | 129 | x = PHI <x' (bb0), ...>; |
130 | ||
131 | MIN/MAX Replacement | |
132 | ------------------- | |
70512b93 | 133 | |
caac37c2 | 134 | This transformation, minmax_replacement replaces |
194899bf | 135 | |
136 | bb0: | |
caac37c2 | 137 | if (a <= b) goto bb2; else goto bb1; |
194899bf | 138 | bb1: |
194899bf | 139 | bb2: |
caac37c2 | 140 | x = PHI <b (bb1), a (bb0), ...>; |
194899bf | 141 | |
caac37c2 | 142 | with |
194899bf | 143 | |
caac37c2 | 144 | bb0: |
145 | x' = MIN_EXPR (a, b) | |
146 | bb2: | |
147 | x = PHI <x' (bb0), ...>; | |
194899bf | 148 | |
239e9670 | 149 | A similar transformation is done for MAX_EXPR. |
150 | ||
151 | ||
152 | This pass also performs a fifth transformation of a slightly different | |
153 | flavor. | |
154 | ||
155 | Adjacent Load Hoisting | |
156 | ---------------------- | |
157 | ||
158 | This transformation replaces | |
159 | ||
160 | bb0: | |
161 | if (...) goto bb2; else goto bb1; | |
162 | bb1: | |
163 | x1 = (<expr>).field1; | |
164 | goto bb3; | |
165 | bb2: | |
166 | x2 = (<expr>).field2; | |
167 | bb3: | |
168 | # x = PHI <x1, x2>; | |
169 | ||
170 | with | |
171 | ||
172 | bb0: | |
173 | x1 = (<expr>).field1; | |
174 | x2 = (<expr>).field2; | |
175 | if (...) goto bb2; else goto bb1; | |
176 | bb1: | |
177 | goto bb3; | |
178 | bb2: | |
179 | bb3: | |
180 | # x = PHI <x1, x2>; | |
181 | ||
182 | The purpose of this transformation is to enable generation of conditional | |
183 | move instructions such as Intel CMOVE or PowerPC ISEL. Because one of | |
184 | the loads is speculative, the transformation is restricted to very | |
185 | specific cases to avoid introducing a page fault. We are looking for | |
186 | the common idiom: | |
187 | ||
188 | if (...) | |
189 | x = y->left; | |
190 | else | |
191 | x = y->right; | |
192 | ||
193 | where left and right are typically adjacent pointers in a tree structure. */ | |
70512b93 | 194 | |
2a1990e9 | 195 | static unsigned int |
4ee9c684 | 196 | tree_ssa_phiopt (void) |
e6d0e152 | 197 | { |
239e9670 | 198 | return tree_ssa_phiopt_worker (false, gate_hoist_loads ()); |
e6d0e152 | 199 | } |
200 | ||
201 | /* This pass tries to transform conditional stores into unconditional | |
202 | ones, enabling further simplifications with the simpler then and else | |
203 | blocks. In particular it replaces this: | |
204 | ||
205 | bb0: | |
206 | if (cond) goto bb2; else goto bb1; | |
207 | bb1: | |
91cf53d5 | 208 | *p = RHS; |
e6d0e152 | 209 | bb2: |
210 | ||
211 | with | |
212 | ||
213 | bb0: | |
214 | if (cond) goto bb1; else goto bb2; | |
215 | bb1: | |
216 | condtmp' = *p; | |
217 | bb2: | |
218 | condtmp = PHI <RHS, condtmp'> | |
91cf53d5 | 219 | *p = condtmp; |
e6d0e152 | 220 | |
221 | This transformation can only be done under several constraints, | |
91cf53d5 | 222 | documented below. It also replaces: |
223 | ||
224 | bb0: | |
225 | if (cond) goto bb2; else goto bb1; | |
226 | bb1: | |
227 | *p = RHS1; | |
228 | goto bb3; | |
229 | bb2: | |
230 | *p = RHS2; | |
231 | bb3: | |
232 | ||
233 | with | |
234 | ||
235 | bb0: | |
236 | if (cond) goto bb3; else goto bb1; | |
237 | bb1: | |
238 | bb3: | |
239 | condtmp = PHI <RHS1, RHS2> | |
240 | *p = condtmp; */ | |
e6d0e152 | 241 | |
242 | static unsigned int | |
243 | tree_ssa_cs_elim (void) | |
244 | { | |
239e9670 | 245 | return tree_ssa_phiopt_worker (true, false); |
e6d0e152 | 246 | } |
247 | ||
c3597b05 | 248 | /* Return the singleton PHI in the SEQ of PHIs for edges E0 and E1. */ |
249 | ||
250 | static gimple | |
251 | single_non_singleton_phi_for_edges (gimple_seq seq, edge e0, edge e1) | |
252 | { | |
253 | gimple_stmt_iterator i; | |
254 | gimple phi = NULL; | |
255 | if (gimple_seq_singleton_p (seq)) | |
256 | return gsi_stmt (gsi_start (seq)); | |
257 | for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i)) | |
258 | { | |
259 | gimple p = gsi_stmt (i); | |
260 | /* If the PHI arguments are equal then we can skip this PHI. */ | |
261 | if (operand_equal_for_phi_arg_p (gimple_phi_arg_def (p, e0->dest_idx), | |
262 | gimple_phi_arg_def (p, e1->dest_idx))) | |
263 | continue; | |
264 | ||
265 | /* If we already have a PHI that has the two edge arguments are | |
266 | different, then return it is not a singleton for these PHIs. */ | |
267 | if (phi) | |
268 | return NULL; | |
269 | ||
270 | phi = p; | |
271 | } | |
272 | return phi; | |
273 | } | |
274 | ||
e6d0e152 | 275 | /* The core routine of conditional store replacement and normal |
276 | phi optimizations. Both share much of the infrastructure in how | |
277 | to match applicable basic block patterns. DO_STORE_ELIM is true | |
239e9670 | 278 | when we want to do conditional store replacement, false otherwise. |
279 | DO_HOIST_LOADS is true when we want to hoist adjacent loads out | |
280 | of diamond control flow patterns, false otherwise. */ | |
e6d0e152 | 281 | static unsigned int |
239e9670 | 282 | tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads) |
4ee9c684 | 283 | { |
284 | basic_block bb; | |
194899bf | 285 | basic_block *bb_order; |
286 | unsigned n, i; | |
1e4b21e3 | 287 | bool cfgchanged = false; |
e6d0e152 | 288 | struct pointer_set_t *nontrap = 0; |
289 | ||
290 | if (do_store_elim) | |
03d37e4e | 291 | /* Calculate the set of non-trapping memory accesses. */ |
292 | nontrap = get_non_trapping (); | |
194899bf | 293 | |
294 | /* Search every basic block for COND_EXPR we may be able to optimize. | |
295 | ||
296 | We walk the blocks in order that guarantees that a block with | |
297 | a single predecessor is processed before the predecessor. | |
298 | This ensures that we collapse inner ifs before visiting the | |
299 | outer ones, and also that we do not try to visit a removed | |
300 | block. */ | |
301 | bb_order = blocks_in_phiopt_order (); | |
4d2e5d52 | 302 | n = n_basic_blocks - NUM_FIXED_BLOCKS; |
4ee9c684 | 303 | |
48e1416a | 304 | for (i = 0; i < n; i++) |
4ee9c684 | 305 | { |
75a70cf9 | 306 | gimple cond_stmt, phi; |
33784d89 | 307 | basic_block bb1, bb2; |
308 | edge e1, e2; | |
194899bf | 309 | tree arg0, arg1; |
310 | ||
311 | bb = bb_order[i]; | |
20e5647c | 312 | |
75a70cf9 | 313 | cond_stmt = last_stmt (bb); |
314 | /* Check to see if the last statement is a GIMPLE_COND. */ | |
315 | if (!cond_stmt | |
316 | || gimple_code (cond_stmt) != GIMPLE_COND) | |
33784d89 | 317 | continue; |
20e5647c | 318 | |
33784d89 | 319 | e1 = EDGE_SUCC (bb, 0); |
320 | bb1 = e1->dest; | |
321 | e2 = EDGE_SUCC (bb, 1); | |
322 | bb2 = e2->dest; | |
20e5647c | 323 | |
33784d89 | 324 | /* We cannot do the optimization on abnormal edges. */ |
325 | if ((e1->flags & EDGE_ABNORMAL) != 0 | |
326 | || (e2->flags & EDGE_ABNORMAL) != 0) | |
327 | continue; | |
20e5647c | 328 | |
33784d89 | 329 | /* If either bb1's succ or bb2 or bb2's succ is non NULL. */ |
ea091dfd | 330 | if (EDGE_COUNT (bb1->succs) == 0 |
33784d89 | 331 | || bb2 == NULL |
ea091dfd | 332 | || EDGE_COUNT (bb2->succs) == 0) |
33784d89 | 333 | continue; |
20e5647c | 334 | |
33784d89 | 335 | /* Find the bb which is the fall through to the other. */ |
336 | if (EDGE_SUCC (bb1, 0)->dest == bb2) | |
337 | ; | |
338 | else if (EDGE_SUCC (bb2, 0)->dest == bb1) | |
339 | { | |
340 | basic_block bb_tmp = bb1; | |
341 | edge e_tmp = e1; | |
342 | bb1 = bb2; | |
343 | bb2 = bb_tmp; | |
344 | e1 = e2; | |
345 | e2 = e_tmp; | |
346 | } | |
91cf53d5 | 347 | else if (do_store_elim |
348 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) | |
349 | { | |
350 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
351 | ||
352 | if (!single_succ_p (bb1) | |
353 | || (EDGE_SUCC (bb1, 0)->flags & EDGE_FALLTHRU) == 0 | |
354 | || !single_succ_p (bb2) | |
355 | || (EDGE_SUCC (bb2, 0)->flags & EDGE_FALLTHRU) == 0 | |
356 | || EDGE_COUNT (bb3->preds) != 2) | |
357 | continue; | |
358 | if (cond_if_else_store_replacement (bb1, bb2, bb3)) | |
359 | cfgchanged = true; | |
360 | continue; | |
361 | } | |
239e9670 | 362 | else if (do_hoist_loads |
363 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) | |
364 | { | |
365 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
366 | ||
367 | if (!FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt))) | |
368 | && single_succ_p (bb1) | |
369 | && single_succ_p (bb2) | |
370 | && single_pred_p (bb1) | |
371 | && single_pred_p (bb2) | |
372 | && EDGE_COUNT (bb->succs) == 2 | |
373 | && EDGE_COUNT (bb3->preds) == 2 | |
374 | /* If one edge or the other is dominant, a conditional move | |
375 | is likely to perform worse than the well-predicted branch. */ | |
376 | && !predictable_edge_p (EDGE_SUCC (bb, 0)) | |
377 | && !predictable_edge_p (EDGE_SUCC (bb, 1))) | |
378 | hoist_adjacent_loads (bb, bb1, bb2, bb3); | |
379 | continue; | |
380 | } | |
33784d89 | 381 | else |
91cf53d5 | 382 | continue; |
20e5647c | 383 | |
33784d89 | 384 | e1 = EDGE_SUCC (bb1, 0); |
20e5647c | 385 | |
33784d89 | 386 | /* Make sure that bb1 is just a fall through. */ |
db5ba14c | 387 | if (!single_succ_p (bb1) |
33784d89 | 388 | || (e1->flags & EDGE_FALLTHRU) == 0) |
389 | continue; | |
20e5647c | 390 | |
3472707f | 391 | /* Also make sure that bb1 only have one predecessor and that it |
392 | is bb. */ | |
ea091dfd | 393 | if (!single_pred_p (bb1) |
394 | || single_pred (bb1) != bb) | |
33784d89 | 395 | continue; |
20e5647c | 396 | |
e6d0e152 | 397 | if (do_store_elim) |
398 | { | |
399 | /* bb1 is the middle block, bb2 the join block, bb the split block, | |
400 | e1 the fallthrough edge from bb1 to bb2. We can't do the | |
401 | optimization if the join block has more than two predecessors. */ | |
402 | if (EDGE_COUNT (bb2->preds) > 2) | |
403 | continue; | |
404 | if (cond_store_replacement (bb1, bb2, e1, e2, nontrap)) | |
405 | cfgchanged = true; | |
406 | } | |
407 | else | |
408 | { | |
75a70cf9 | 409 | gimple_seq phis = phi_nodes (bb2); |
2109076a | 410 | gimple_stmt_iterator gsi; |
fb9912ea | 411 | bool candorest = true; |
c3597b05 | 412 | |
fb9912ea | 413 | /* Value replacement can work with more than one PHI |
414 | so try that first. */ | |
415 | for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi)) | |
416 | { | |
417 | phi = gsi_stmt (gsi); | |
418 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); | |
419 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
420 | if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2) | |
421 | { | |
422 | candorest = false; | |
423 | cfgchanged = true; | |
424 | break; | |
425 | } | |
426 | } | |
e6d0e152 | 427 | |
fb9912ea | 428 | if (!candorest) |
429 | continue; | |
c3597b05 | 430 | |
431 | phi = single_non_singleton_phi_for_edges (phis, e1, e2); | |
2109076a | 432 | if (!phi) |
e6d0e152 | 433 | continue; |
434 | ||
75a70cf9 | 435 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); |
436 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
e6d0e152 | 437 | |
438 | /* Something is wrong if we cannot find the arguments in the PHI | |
439 | node. */ | |
440 | gcc_assert (arg0 != NULL && arg1 != NULL); | |
441 | ||
442 | /* Do the replacement of conditional if it can be done. */ | |
443 | if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
444 | cfgchanged = true; | |
e6d0e152 | 445 | else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) |
446 | cfgchanged = true; | |
447 | else if (minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
448 | cfgchanged = true; | |
449 | } | |
194899bf | 450 | } |
451 | ||
452 | free (bb_order); | |
48e1416a | 453 | |
e6d0e152 | 454 | if (do_store_elim) |
455 | pointer_set_destroy (nontrap); | |
456 | /* If the CFG has changed, we should cleanup the CFG. */ | |
457 | if (cfgchanged && do_store_elim) | |
458 | { | |
459 | /* In cond-store replacement we have added some loads on edges | |
460 | and new VOPS (as we moved the store, and created a load). */ | |
75a70cf9 | 461 | gsi_commit_edge_inserts (); |
e6d0e152 | 462 | return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals; |
463 | } | |
464 | else if (cfgchanged) | |
465 | return TODO_cleanup_cfg; | |
466 | return 0; | |
194899bf | 467 | } |
468 | ||
469 | /* Returns the list of basic blocks in the function in an order that guarantees | |
470 | that if a block X has just a single predecessor Y, then Y is after X in the | |
471 | ordering. */ | |
472 | ||
8530c7be | 473 | basic_block * |
194899bf | 474 | blocks_in_phiopt_order (void) |
475 | { | |
476 | basic_block x, y; | |
945865c5 | 477 | basic_block *order = XNEWVEC (basic_block, n_basic_blocks); |
48e1416a | 478 | unsigned n = n_basic_blocks - NUM_FIXED_BLOCKS; |
4d2e5d52 | 479 | unsigned np, i; |
48e1416a | 480 | sbitmap visited = sbitmap_alloc (last_basic_block); |
194899bf | 481 | |
48e1416a | 482 | #define MARK_VISITED(BB) (SET_BIT (visited, (BB)->index)) |
483 | #define VISITED_P(BB) (TEST_BIT (visited, (BB)->index)) | |
194899bf | 484 | |
53c5d9d4 | 485 | bitmap_clear (visited); |
194899bf | 486 | |
487 | MARK_VISITED (ENTRY_BLOCK_PTR); | |
488 | FOR_EACH_BB (x) | |
489 | { | |
490 | if (VISITED_P (x)) | |
491 | continue; | |
492 | ||
493 | /* Walk the predecessors of x as long as they have precisely one | |
494 | predecessor and add them to the list, so that they get stored | |
495 | after x. */ | |
496 | for (y = x, np = 1; | |
497 | single_pred_p (y) && !VISITED_P (single_pred (y)); | |
498 | y = single_pred (y)) | |
499 | np++; | |
500 | for (y = x, i = n - np; | |
501 | single_pred_p (y) && !VISITED_P (single_pred (y)); | |
502 | y = single_pred (y), i++) | |
503 | { | |
504 | order[i] = y; | |
505 | MARK_VISITED (y); | |
2ab0a163 | 506 | } |
194899bf | 507 | order[i] = y; |
508 | MARK_VISITED (y); | |
509 | ||
510 | gcc_assert (i == n - 1); | |
511 | n -= np; | |
4ee9c684 | 512 | } |
194899bf | 513 | |
514 | sbitmap_free (visited); | |
515 | gcc_assert (n == 0); | |
516 | return order; | |
517 | ||
518 | #undef MARK_VISITED | |
519 | #undef VISITED_P | |
4ee9c684 | 520 | } |
521 | ||
fccee353 | 522 | /* Replace PHI node element whose edge is E in block BB with variable NEW. |
33784d89 | 523 | Remove the edge from COND_BLOCK which does not lead to BB (COND_BLOCK |
902929aa | 524 | is known to have two edges, one of which must reach BB). */ |
525 | ||
526 | static void | |
a4844041 | 527 | replace_phi_edge_with_variable (basic_block cond_block, |
75a70cf9 | 528 | edge e, gimple phi, tree new_tree) |
902929aa | 529 | { |
75a70cf9 | 530 | basic_block bb = gimple_bb (phi); |
0e1a77e1 | 531 | basic_block block_to_remove; |
75a70cf9 | 532 | gimple_stmt_iterator gsi; |
33784d89 | 533 | |
20e5647c | 534 | /* Change the PHI argument to new. */ |
f0d6e81c | 535 | SET_USE (PHI_ARG_DEF_PTR (phi, e->dest_idx), new_tree); |
0e1a77e1 | 536 | |
0e1a77e1 | 537 | /* Remove the empty basic block. */ |
cd665a06 | 538 | if (EDGE_SUCC (cond_block, 0)->dest == bb) |
902929aa | 539 | { |
cd665a06 | 540 | EDGE_SUCC (cond_block, 0)->flags |= EDGE_FALLTHRU; |
541 | EDGE_SUCC (cond_block, 0)->flags &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); | |
81c5be57 | 542 | EDGE_SUCC (cond_block, 0)->probability = REG_BR_PROB_BASE; |
543 | EDGE_SUCC (cond_block, 0)->count += EDGE_SUCC (cond_block, 1)->count; | |
0e1a77e1 | 544 | |
cd665a06 | 545 | block_to_remove = EDGE_SUCC (cond_block, 1)->dest; |
902929aa | 546 | } |
547 | else | |
548 | { | |
cd665a06 | 549 | EDGE_SUCC (cond_block, 1)->flags |= EDGE_FALLTHRU; |
550 | EDGE_SUCC (cond_block, 1)->flags | |
902929aa | 551 | &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); |
81c5be57 | 552 | EDGE_SUCC (cond_block, 1)->probability = REG_BR_PROB_BASE; |
553 | EDGE_SUCC (cond_block, 1)->count += EDGE_SUCC (cond_block, 0)->count; | |
0e1a77e1 | 554 | |
cd665a06 | 555 | block_to_remove = EDGE_SUCC (cond_block, 0)->dest; |
902929aa | 556 | } |
0e1a77e1 | 557 | delete_basic_block (block_to_remove); |
20e5647c | 558 | |
902929aa | 559 | /* Eliminate the COND_EXPR at the end of COND_BLOCK. */ |
75a70cf9 | 560 | gsi = gsi_last_bb (cond_block); |
561 | gsi_remove (&gsi, true); | |
20e5647c | 562 | |
902929aa | 563 | if (dump_file && (dump_flags & TDF_DETAILS)) |
564 | fprintf (dump_file, | |
565 | "COND_EXPR in block %d and PHI in block %d converted to straightline code.\n", | |
566 | cond_block->index, | |
567 | bb->index); | |
568 | } | |
569 | ||
570 | /* The function conditional_replacement does the main work of doing the | |
571 | conditional replacement. Return true if the replacement is done. | |
572 | Otherwise return false. | |
573 | BB is the basic block where the replacement is going to be done on. ARG0 | |
dac49aa5 | 574 | is argument 0 from PHI. Likewise for ARG1. */ |
902929aa | 575 | |
576 | static bool | |
33784d89 | 577 | conditional_replacement (basic_block cond_bb, basic_block middle_bb, |
75a70cf9 | 578 | edge e0, edge e1, gimple phi, |
33784d89 | 579 | tree arg0, tree arg1) |
902929aa | 580 | { |
581 | tree result; | |
75a70cf9 | 582 | gimple stmt, new_stmt; |
583 | tree cond; | |
584 | gimple_stmt_iterator gsi; | |
902929aa | 585 | edge true_edge, false_edge; |
75a70cf9 | 586 | tree new_var, new_var2; |
678919fd | 587 | bool neg; |
902929aa | 588 | |
435e1a75 | 589 | /* FIXME: Gimplification of complex type is too hard for now. */ |
47b88316 | 590 | /* We aren't prepared to handle vectors either (and it is a question |
591 | if it would be worthwhile anyway). */ | |
592 | if (!(INTEGRAL_TYPE_P (TREE_TYPE (arg0)) | |
593 | || POINTER_TYPE_P (TREE_TYPE (arg0))) | |
594 | || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
595 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) | |
435e1a75 | 596 | return false; |
597 | ||
678919fd | 598 | /* The PHI arguments have the constants 0 and 1, or 0 and -1, then |
599 | convert it to the conditional. */ | |
902929aa | 600 | if ((integer_zerop (arg0) && integer_onep (arg1)) |
601 | || (integer_zerop (arg1) && integer_onep (arg0))) | |
678919fd | 602 | neg = false; |
603 | else if ((integer_zerop (arg0) && integer_all_onesp (arg1)) | |
604 | || (integer_zerop (arg1) && integer_all_onesp (arg0))) | |
605 | neg = true; | |
902929aa | 606 | else |
607 | return false; | |
20e5647c | 608 | |
33784d89 | 609 | if (!empty_block_p (middle_bb)) |
902929aa | 610 | return false; |
20e5647c | 611 | |
75a70cf9 | 612 | /* At this point we know we have a GIMPLE_COND with two successors. |
2ab0a163 | 613 | One successor is BB, the other successor is an empty block which |
614 | falls through into BB. | |
20e5647c | 615 | |
2ab0a163 | 616 | There is a single PHI node at the join point (BB) and its arguments |
678919fd | 617 | are constants (0, 1) or (0, -1). |
20e5647c | 618 | |
2ab0a163 | 619 | So, given the condition COND, and the two PHI arguments, we can |
20e5647c | 620 | rewrite this PHI into non-branching code: |
621 | ||
2ab0a163 | 622 | dest = (COND) or dest = COND' |
20e5647c | 623 | |
2ab0a163 | 624 | We use the condition as-is if the argument associated with the |
625 | true edge has the value one or the argument associated with the | |
626 | false edge as the value zero. Note that those conditions are not | |
75a70cf9 | 627 | the same since only one of the outgoing edges from the GIMPLE_COND |
2ab0a163 | 628 | will directly reach BB and thus be associated with an argument. */ |
ae5a4794 | 629 | |
75a70cf9 | 630 | stmt = last_stmt (cond_bb); |
631 | result = PHI_RESULT (phi); | |
b2a02a0e | 632 | |
75a70cf9 | 633 | /* To handle special cases like floating point comparison, it is easier and |
634 | less error-prone to build a tree and gimplify it on the fly though it is | |
635 | less efficient. */ | |
6f9714b3 | 636 | cond = fold_build2_loc (gimple_location (stmt), |
637 | gimple_cond_code (stmt), boolean_type_node, | |
638 | gimple_cond_lhs (stmt), gimple_cond_rhs (stmt)); | |
4ee9c684 | 639 | |
75a70cf9 | 640 | /* We need to know which is the true edge and which is the false |
641 | edge so that we know when to invert the condition below. */ | |
642 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
643 | if ((e0 == true_edge && integer_zerop (arg0)) | |
678919fd | 644 | || (e0 == false_edge && !integer_zerop (arg0)) |
75a70cf9 | 645 | || (e1 == true_edge && integer_zerop (arg1)) |
678919fd | 646 | || (e1 == false_edge && !integer_zerop (arg1))) |
6f9714b3 | 647 | cond = fold_build1_loc (gimple_location (stmt), |
678919fd | 648 | TRUTH_NOT_EXPR, TREE_TYPE (cond), cond); |
649 | ||
650 | if (neg) | |
651 | { | |
652 | cond = fold_convert_loc (gimple_location (stmt), | |
653 | TREE_TYPE (result), cond); | |
654 | cond = fold_build1_loc (gimple_location (stmt), | |
655 | NEGATE_EXPR, TREE_TYPE (cond), cond); | |
656 | } | |
75a70cf9 | 657 | |
658 | /* Insert our new statements at the end of conditional block before the | |
659 | COND_STMT. */ | |
660 | gsi = gsi_for_stmt (stmt); | |
661 | new_var = force_gimple_operand_gsi (&gsi, cond, true, NULL, true, | |
662 | GSI_SAME_STMT); | |
663 | ||
664 | if (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (new_var))) | |
665 | { | |
efbcb6de | 666 | source_location locus_0, locus_1; |
667 | ||
03d37e4e | 668 | new_var2 = make_ssa_name (TREE_TYPE (result), NULL); |
75a70cf9 | 669 | new_stmt = gimple_build_assign_with_ops (CONVERT_EXPR, new_var2, |
670 | new_var, NULL); | |
75a70cf9 | 671 | gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); |
672 | new_var = new_var2; | |
efbcb6de | 673 | |
674 | /* Set the locus to the first argument, unless is doesn't have one. */ | |
675 | locus_0 = gimple_phi_arg_location (phi, 0); | |
676 | locus_1 = gimple_phi_arg_location (phi, 1); | |
677 | if (locus_0 == UNKNOWN_LOCATION) | |
678 | locus_0 = locus_1; | |
679 | gimple_set_location (new_stmt, locus_0); | |
4ee9c684 | 680 | } |
20e5647c | 681 | |
75a70cf9 | 682 | replace_phi_edge_with_variable (cond_bb, e1, phi, new_var); |
902929aa | 683 | |
4ee9c684 | 684 | /* Note that we optimized this PHI. */ |
685 | return true; | |
686 | } | |
687 | ||
17b9476e | 688 | /* Update *ARG which is defined in STMT so that it contains the |
689 | computed value if that seems profitable. Return true if the | |
690 | statement is made dead by that rewriting. */ | |
691 | ||
692 | static bool | |
693 | jump_function_from_stmt (tree *arg, gimple stmt) | |
694 | { | |
695 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
696 | if (code == ADDR_EXPR) | |
697 | { | |
698 | /* For arg = &p->i transform it to p, if possible. */ | |
699 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
700 | HOST_WIDE_INT offset; | |
701 | tree tem = get_addr_base_and_unit_offset (TREE_OPERAND (rhs1, 0), | |
702 | &offset); | |
703 | if (tem | |
704 | && TREE_CODE (tem) == MEM_REF | |
cf8f0e63 | 705 | && (mem_ref_offset (tem) + double_int::from_shwi (offset)).is_zero ()) |
17b9476e | 706 | { |
707 | *arg = TREE_OPERAND (tem, 0); | |
708 | return true; | |
709 | } | |
710 | } | |
711 | /* TODO: Much like IPA-CP jump-functions we want to handle constant | |
712 | additions symbolically here, and we'd need to update the comparison | |
713 | code that compares the arg + cst tuples in our caller. For now the | |
714 | code above exactly handles the VEC_BASE pattern from vec.h. */ | |
715 | return false; | |
716 | } | |
717 | ||
0beac6fc | 718 | /* The function value_replacement does the main work of doing the value |
fb9912ea | 719 | replacement. Return non-zero if the replacement is done. Otherwise return |
720 | 0. If we remove the middle basic block, return 2. | |
0beac6fc | 721 | BB is the basic block where the replacement is going to be done on. ARG0 |
dac49aa5 | 722 | is argument 0 from the PHI. Likewise for ARG1. */ |
0beac6fc | 723 | |
fb9912ea | 724 | static int |
33784d89 | 725 | value_replacement (basic_block cond_bb, basic_block middle_bb, |
75a70cf9 | 726 | edge e0, edge e1, gimple phi, |
33784d89 | 727 | tree arg0, tree arg1) |
0beac6fc | 728 | { |
17b9476e | 729 | gimple_stmt_iterator gsi; |
75a70cf9 | 730 | gimple cond; |
0beac6fc | 731 | edge true_edge, false_edge; |
75a70cf9 | 732 | enum tree_code code; |
fb9912ea | 733 | bool emtpy_or_with_defined_p = true; |
0beac6fc | 734 | |
735 | /* If the type says honor signed zeros we cannot do this | |
dac49aa5 | 736 | optimization. */ |
0beac6fc | 737 | if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) |
fb9912ea | 738 | return 0; |
0beac6fc | 739 | |
fb9912ea | 740 | /* If there is a statement in MIDDLE_BB that defines one of the PHI |
741 | arguments, then adjust arg0 or arg1. */ | |
17b9476e | 742 | gsi = gsi_after_labels (middle_bb); |
fb9912ea | 743 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) |
744 | gsi_next_nondebug (&gsi); | |
745 | while (!gsi_end_p (gsi)) | |
17b9476e | 746 | { |
fb9912ea | 747 | gimple stmt = gsi_stmt (gsi); |
748 | tree lhs; | |
749 | gsi_next_nondebug (&gsi); | |
750 | if (!is_gimple_assign (stmt)) | |
17b9476e | 751 | { |
fb9912ea | 752 | emtpy_or_with_defined_p = false; |
753 | continue; | |
17b9476e | 754 | } |
fb9912ea | 755 | /* Now try to adjust arg0 or arg1 according to the computation |
756 | in the statement. */ | |
757 | lhs = gimple_assign_lhs (stmt); | |
758 | if (!(lhs == arg0 | |
759 | && jump_function_from_stmt (&arg0, stmt)) | |
760 | || (lhs == arg1 | |
761 | && jump_function_from_stmt (&arg1, stmt))) | |
762 | emtpy_or_with_defined_p = false; | |
17b9476e | 763 | } |
0beac6fc | 764 | |
75a70cf9 | 765 | cond = last_stmt (cond_bb); |
766 | code = gimple_cond_code (cond); | |
0beac6fc | 767 | |
768 | /* This transformation is only valid for equality comparisons. */ | |
75a70cf9 | 769 | if (code != NE_EXPR && code != EQ_EXPR) |
fb9912ea | 770 | return 0; |
0beac6fc | 771 | |
772 | /* We need to know which is the true edge and which is the false | |
773 | edge so that we know if have abs or negative abs. */ | |
33784d89 | 774 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
0beac6fc | 775 | |
776 | /* At this point we know we have a COND_EXPR with two successors. | |
777 | One successor is BB, the other successor is an empty block which | |
778 | falls through into BB. | |
779 | ||
780 | The condition for the COND_EXPR is known to be NE_EXPR or EQ_EXPR. | |
781 | ||
782 | There is a single PHI node at the join point (BB) with two arguments. | |
783 | ||
784 | We now need to verify that the two arguments in the PHI node match | |
785 | the two arguments to the equality comparison. */ | |
20e5647c | 786 | |
75a70cf9 | 787 | if ((operand_equal_for_phi_arg_p (arg0, gimple_cond_lhs (cond)) |
788 | && operand_equal_for_phi_arg_p (arg1, gimple_cond_rhs (cond))) | |
789 | || (operand_equal_for_phi_arg_p (arg1, gimple_cond_lhs (cond)) | |
790 | && operand_equal_for_phi_arg_p (arg0, gimple_cond_rhs (cond)))) | |
0beac6fc | 791 | { |
792 | edge e; | |
793 | tree arg; | |
794 | ||
50737d20 | 795 | /* For NE_EXPR, we want to build an assignment result = arg where |
796 | arg is the PHI argument associated with the true edge. For | |
797 | EQ_EXPR we want the PHI argument associated with the false edge. */ | |
75a70cf9 | 798 | e = (code == NE_EXPR ? true_edge : false_edge); |
50737d20 | 799 | |
800 | /* Unfortunately, E may not reach BB (it may instead have gone to | |
801 | OTHER_BLOCK). If that is the case, then we want the single outgoing | |
802 | edge from OTHER_BLOCK which reaches BB and represents the desired | |
803 | path from COND_BLOCK. */ | |
33784d89 | 804 | if (e->dest == middle_bb) |
ea091dfd | 805 | e = single_succ_edge (e->dest); |
50737d20 | 806 | |
807 | /* Now we know the incoming edge to BB that has the argument for the | |
808 | RHS of our new assignment statement. */ | |
33784d89 | 809 | if (e0 == e) |
0beac6fc | 810 | arg = arg0; |
811 | else | |
812 | arg = arg1; | |
813 | ||
fb9912ea | 814 | /* If the middle basic block was empty or is defining the |
c3597b05 | 815 | PHI arguments and this is a single phi where the args are different |
816 | for the edges e0 and e1 then we can remove the middle basic block. */ | |
fb9912ea | 817 | if (emtpy_or_with_defined_p |
c3597b05 | 818 | && single_non_singleton_phi_for_edges (phi_nodes (gimple_bb (phi)), |
819 | e0, e1)) | |
fb9912ea | 820 | { |
821 | replace_phi_edge_with_variable (cond_bb, e1, phi, arg); | |
822 | /* Note that we optimized this PHI. */ | |
823 | return 2; | |
824 | } | |
825 | else | |
826 | { | |
827 | /* Replace the PHI arguments with arg. */ | |
828 | SET_PHI_ARG_DEF (phi, e0->dest_idx, arg); | |
829 | SET_PHI_ARG_DEF (phi, e1->dest_idx, arg); | |
830 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
831 | { | |
832 | fprintf (dump_file, "PHI "); | |
833 | print_generic_expr (dump_file, gimple_phi_result (phi), 0); | |
c3597b05 | 834 | fprintf (dump_file, " reduced for COND_EXPR in block %d to ", |
835 | cond_bb->index); | |
fb9912ea | 836 | print_generic_expr (dump_file, arg, 0); |
837 | fprintf (dump_file, ".\n"); | |
838 | } | |
839 | return 1; | |
840 | } | |
0beac6fc | 841 | |
0beac6fc | 842 | } |
fb9912ea | 843 | return 0; |
0beac6fc | 844 | } |
845 | ||
194899bf | 846 | /* The function minmax_replacement does the main work of doing the minmax |
847 | replacement. Return true if the replacement is done. Otherwise return | |
848 | false. | |
849 | BB is the basic block where the replacement is going to be done on. ARG0 | |
850 | is argument 0 from the PHI. Likewise for ARG1. */ | |
851 | ||
852 | static bool | |
853 | minmax_replacement (basic_block cond_bb, basic_block middle_bb, | |
75a70cf9 | 854 | edge e0, edge e1, gimple phi, |
194899bf | 855 | tree arg0, tree arg1) |
856 | { | |
857 | tree result, type; | |
75a70cf9 | 858 | gimple cond, new_stmt; |
194899bf | 859 | edge true_edge, false_edge; |
860 | enum tree_code cmp, minmax, ass_code; | |
861 | tree smaller, larger, arg_true, arg_false; | |
75a70cf9 | 862 | gimple_stmt_iterator gsi, gsi_from; |
194899bf | 863 | |
864 | type = TREE_TYPE (PHI_RESULT (phi)); | |
865 | ||
866 | /* The optimization may be unsafe due to NaNs. */ | |
867 | if (HONOR_NANS (TYPE_MODE (type))) | |
868 | return false; | |
869 | ||
75a70cf9 | 870 | cond = last_stmt (cond_bb); |
871 | cmp = gimple_cond_code (cond); | |
194899bf | 872 | |
873 | /* This transformation is only valid for order comparisons. Record which | |
874 | operand is smaller/larger if the result of the comparison is true. */ | |
875 | if (cmp == LT_EXPR || cmp == LE_EXPR) | |
876 | { | |
75a70cf9 | 877 | smaller = gimple_cond_lhs (cond); |
878 | larger = gimple_cond_rhs (cond); | |
194899bf | 879 | } |
880 | else if (cmp == GT_EXPR || cmp == GE_EXPR) | |
881 | { | |
75a70cf9 | 882 | smaller = gimple_cond_rhs (cond); |
883 | larger = gimple_cond_lhs (cond); | |
194899bf | 884 | } |
885 | else | |
886 | return false; | |
887 | ||
888 | /* We need to know which is the true edge and which is the false | |
889 | edge so that we know if have abs or negative abs. */ | |
890 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
891 | ||
892 | /* Forward the edges over the middle basic block. */ | |
893 | if (true_edge->dest == middle_bb) | |
894 | true_edge = EDGE_SUCC (true_edge->dest, 0); | |
895 | if (false_edge->dest == middle_bb) | |
896 | false_edge = EDGE_SUCC (false_edge->dest, 0); | |
897 | ||
898 | if (true_edge == e0) | |
899 | { | |
900 | gcc_assert (false_edge == e1); | |
901 | arg_true = arg0; | |
902 | arg_false = arg1; | |
903 | } | |
904 | else | |
905 | { | |
906 | gcc_assert (false_edge == e0); | |
907 | gcc_assert (true_edge == e1); | |
908 | arg_true = arg1; | |
909 | arg_false = arg0; | |
910 | } | |
911 | ||
912 | if (empty_block_p (middle_bb)) | |
913 | { | |
914 | if (operand_equal_for_phi_arg_p (arg_true, smaller) | |
915 | && operand_equal_for_phi_arg_p (arg_false, larger)) | |
916 | { | |
917 | /* Case | |
48e1416a | 918 | |
194899bf | 919 | if (smaller < larger) |
920 | rslt = smaller; | |
921 | else | |
922 | rslt = larger; */ | |
923 | minmax = MIN_EXPR; | |
924 | } | |
925 | else if (operand_equal_for_phi_arg_p (arg_false, smaller) | |
926 | && operand_equal_for_phi_arg_p (arg_true, larger)) | |
927 | minmax = MAX_EXPR; | |
928 | else | |
929 | return false; | |
930 | } | |
931 | else | |
932 | { | |
933 | /* Recognize the following case, assuming d <= u: | |
934 | ||
935 | if (a <= u) | |
936 | b = MAX (a, d); | |
937 | x = PHI <b, u> | |
938 | ||
939 | This is equivalent to | |
940 | ||
941 | b = MAX (a, d); | |
942 | x = MIN (b, u); */ | |
943 | ||
75a70cf9 | 944 | gimple assign = last_and_only_stmt (middle_bb); |
945 | tree lhs, op0, op1, bound; | |
194899bf | 946 | |
947 | if (!assign | |
75a70cf9 | 948 | || gimple_code (assign) != GIMPLE_ASSIGN) |
194899bf | 949 | return false; |
950 | ||
75a70cf9 | 951 | lhs = gimple_assign_lhs (assign); |
952 | ass_code = gimple_assign_rhs_code (assign); | |
194899bf | 953 | if (ass_code != MAX_EXPR && ass_code != MIN_EXPR) |
954 | return false; | |
75a70cf9 | 955 | op0 = gimple_assign_rhs1 (assign); |
956 | op1 = gimple_assign_rhs2 (assign); | |
194899bf | 957 | |
958 | if (true_edge->src == middle_bb) | |
959 | { | |
960 | /* We got here if the condition is true, i.e., SMALLER < LARGER. */ | |
961 | if (!operand_equal_for_phi_arg_p (lhs, arg_true)) | |
962 | return false; | |
963 | ||
964 | if (operand_equal_for_phi_arg_p (arg_false, larger)) | |
965 | { | |
966 | /* Case | |
967 | ||
968 | if (smaller < larger) | |
969 | { | |
970 | r' = MAX_EXPR (smaller, bound) | |
971 | } | |
972 | r = PHI <r', larger> --> to be turned to MIN_EXPR. */ | |
973 | if (ass_code != MAX_EXPR) | |
974 | return false; | |
975 | ||
976 | minmax = MIN_EXPR; | |
977 | if (operand_equal_for_phi_arg_p (op0, smaller)) | |
978 | bound = op1; | |
979 | else if (operand_equal_for_phi_arg_p (op1, smaller)) | |
980 | bound = op0; | |
981 | else | |
982 | return false; | |
983 | ||
984 | /* We need BOUND <= LARGER. */ | |
49d00087 | 985 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
986 | bound, larger))) | |
194899bf | 987 | return false; |
988 | } | |
989 | else if (operand_equal_for_phi_arg_p (arg_false, smaller)) | |
990 | { | |
991 | /* Case | |
992 | ||
993 | if (smaller < larger) | |
994 | { | |
995 | r' = MIN_EXPR (larger, bound) | |
996 | } | |
997 | r = PHI <r', smaller> --> to be turned to MAX_EXPR. */ | |
998 | if (ass_code != MIN_EXPR) | |
999 | return false; | |
1000 | ||
1001 | minmax = MAX_EXPR; | |
1002 | if (operand_equal_for_phi_arg_p (op0, larger)) | |
1003 | bound = op1; | |
1004 | else if (operand_equal_for_phi_arg_p (op1, larger)) | |
1005 | bound = op0; | |
1006 | else | |
1007 | return false; | |
1008 | ||
1009 | /* We need BOUND >= SMALLER. */ | |
49d00087 | 1010 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1011 | bound, smaller))) | |
194899bf | 1012 | return false; |
1013 | } | |
1014 | else | |
1015 | return false; | |
1016 | } | |
1017 | else | |
1018 | { | |
1019 | /* We got here if the condition is false, i.e., SMALLER > LARGER. */ | |
1020 | if (!operand_equal_for_phi_arg_p (lhs, arg_false)) | |
1021 | return false; | |
1022 | ||
1023 | if (operand_equal_for_phi_arg_p (arg_true, larger)) | |
1024 | { | |
1025 | /* Case | |
1026 | ||
1027 | if (smaller > larger) | |
1028 | { | |
1029 | r' = MIN_EXPR (smaller, bound) | |
1030 | } | |
1031 | r = PHI <r', larger> --> to be turned to MAX_EXPR. */ | |
1032 | if (ass_code != MIN_EXPR) | |
1033 | return false; | |
1034 | ||
1035 | minmax = MAX_EXPR; | |
1036 | if (operand_equal_for_phi_arg_p (op0, smaller)) | |
1037 | bound = op1; | |
1038 | else if (operand_equal_for_phi_arg_p (op1, smaller)) | |
1039 | bound = op0; | |
1040 | else | |
1041 | return false; | |
1042 | ||
1043 | /* We need BOUND >= LARGER. */ | |
49d00087 | 1044 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1045 | bound, larger))) | |
194899bf | 1046 | return false; |
1047 | } | |
1048 | else if (operand_equal_for_phi_arg_p (arg_true, smaller)) | |
1049 | { | |
1050 | /* Case | |
1051 | ||
1052 | if (smaller > larger) | |
1053 | { | |
1054 | r' = MAX_EXPR (larger, bound) | |
1055 | } | |
1056 | r = PHI <r', smaller> --> to be turned to MIN_EXPR. */ | |
1057 | if (ass_code != MAX_EXPR) | |
1058 | return false; | |
1059 | ||
1060 | minmax = MIN_EXPR; | |
1061 | if (operand_equal_for_phi_arg_p (op0, larger)) | |
1062 | bound = op1; | |
1063 | else if (operand_equal_for_phi_arg_p (op1, larger)) | |
1064 | bound = op0; | |
1065 | else | |
1066 | return false; | |
1067 | ||
1068 | /* We need BOUND <= SMALLER. */ | |
49d00087 | 1069 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
1070 | bound, smaller))) | |
194899bf | 1071 | return false; |
1072 | } | |
1073 | else | |
1074 | return false; | |
1075 | } | |
1076 | ||
1077 | /* Move the statement from the middle block. */ | |
75a70cf9 | 1078 | gsi = gsi_last_bb (cond_bb); |
445a6ba5 | 1079 | gsi_from = gsi_last_nondebug_bb (middle_bb); |
75a70cf9 | 1080 | gsi_move_before (&gsi_from, &gsi); |
194899bf | 1081 | } |
1082 | ||
1083 | /* Emit the statement to compute min/max. */ | |
1084 | result = duplicate_ssa_name (PHI_RESULT (phi), NULL); | |
75a70cf9 | 1085 | new_stmt = gimple_build_assign_with_ops (minmax, result, arg0, arg1); |
1086 | gsi = gsi_last_bb (cond_bb); | |
1087 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
194899bf | 1088 | |
a4844041 | 1089 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
194899bf | 1090 | return true; |
1091 | } | |
1092 | ||
70512b93 | 1093 | /* The function absolute_replacement does the main work of doing the absolute |
1094 | replacement. Return true if the replacement is done. Otherwise return | |
1095 | false. | |
1096 | bb is the basic block where the replacement is going to be done on. arg0 | |
f7f07c95 | 1097 | is argument 0 from the phi. Likewise for arg1. */ |
33784d89 | 1098 | |
70512b93 | 1099 | static bool |
33784d89 | 1100 | abs_replacement (basic_block cond_bb, basic_block middle_bb, |
a4844041 | 1101 | edge e0 ATTRIBUTE_UNUSED, edge e1, |
75a70cf9 | 1102 | gimple phi, tree arg0, tree arg1) |
70512b93 | 1103 | { |
1104 | tree result; | |
75a70cf9 | 1105 | gimple new_stmt, cond; |
1106 | gimple_stmt_iterator gsi; | |
70512b93 | 1107 | edge true_edge, false_edge; |
75a70cf9 | 1108 | gimple assign; |
70512b93 | 1109 | edge e; |
194899bf | 1110 | tree rhs, lhs; |
70512b93 | 1111 | bool negate; |
1112 | enum tree_code cond_code; | |
1113 | ||
1114 | /* If the type says honor signed zeros we cannot do this | |
dac49aa5 | 1115 | optimization. */ |
70512b93 | 1116 | if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) |
1117 | return false; | |
1118 | ||
70512b93 | 1119 | /* OTHER_BLOCK must have only one executable statement which must have the |
1120 | form arg0 = -arg1 or arg1 = -arg0. */ | |
70512b93 | 1121 | |
194899bf | 1122 | assign = last_and_only_stmt (middle_bb); |
70512b93 | 1123 | /* If we did not find the proper negation assignment, then we can not |
1124 | optimize. */ | |
1125 | if (assign == NULL) | |
1126 | return false; | |
48e1416a | 1127 | |
194899bf | 1128 | /* If we got here, then we have found the only executable statement |
1129 | in OTHER_BLOCK. If it is anything other than arg = -arg1 or | |
1130 | arg1 = -arg0, then we can not optimize. */ | |
75a70cf9 | 1131 | if (gimple_code (assign) != GIMPLE_ASSIGN) |
194899bf | 1132 | return false; |
1133 | ||
75a70cf9 | 1134 | lhs = gimple_assign_lhs (assign); |
194899bf | 1135 | |
75a70cf9 | 1136 | if (gimple_assign_rhs_code (assign) != NEGATE_EXPR) |
194899bf | 1137 | return false; |
1138 | ||
75a70cf9 | 1139 | rhs = gimple_assign_rhs1 (assign); |
48e1416a | 1140 | |
194899bf | 1141 | /* The assignment has to be arg0 = -arg1 or arg1 = -arg0. */ |
1142 | if (!(lhs == arg0 && rhs == arg1) | |
1143 | && !(lhs == arg1 && rhs == arg0)) | |
1144 | return false; | |
70512b93 | 1145 | |
75a70cf9 | 1146 | cond = last_stmt (cond_bb); |
70512b93 | 1147 | result = PHI_RESULT (phi); |
1148 | ||
1149 | /* Only relationals comparing arg[01] against zero are interesting. */ | |
75a70cf9 | 1150 | cond_code = gimple_cond_code (cond); |
70512b93 | 1151 | if (cond_code != GT_EXPR && cond_code != GE_EXPR |
1152 | && cond_code != LT_EXPR && cond_code != LE_EXPR) | |
1153 | return false; | |
1154 | ||
dac49aa5 | 1155 | /* Make sure the conditional is arg[01] OP y. */ |
75a70cf9 | 1156 | if (gimple_cond_lhs (cond) != rhs) |
70512b93 | 1157 | return false; |
1158 | ||
75a70cf9 | 1159 | if (FLOAT_TYPE_P (TREE_TYPE (gimple_cond_rhs (cond))) |
1160 | ? real_zerop (gimple_cond_rhs (cond)) | |
1161 | : integer_zerop (gimple_cond_rhs (cond))) | |
70512b93 | 1162 | ; |
1163 | else | |
1164 | return false; | |
1165 | ||
1166 | /* We need to know which is the true edge and which is the false | |
1167 | edge so that we know if have abs or negative abs. */ | |
33784d89 | 1168 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
70512b93 | 1169 | |
1170 | /* For GT_EXPR/GE_EXPR, if the true edge goes to OTHER_BLOCK, then we | |
1171 | will need to negate the result. Similarly for LT_EXPR/LE_EXPR if | |
1172 | the false edge goes to OTHER_BLOCK. */ | |
1173 | if (cond_code == GT_EXPR || cond_code == GE_EXPR) | |
1174 | e = true_edge; | |
1175 | else | |
1176 | e = false_edge; | |
20e5647c | 1177 | |
33784d89 | 1178 | if (e->dest == middle_bb) |
70512b93 | 1179 | negate = true; |
1180 | else | |
1181 | negate = false; | |
20e5647c | 1182 | |
33784d89 | 1183 | result = duplicate_ssa_name (result, NULL); |
20e5647c | 1184 | |
70512b93 | 1185 | if (negate) |
03d37e4e | 1186 | lhs = make_ssa_name (TREE_TYPE (result), NULL); |
70512b93 | 1187 | else |
1188 | lhs = result; | |
1189 | ||
dac49aa5 | 1190 | /* Build the modify expression with abs expression. */ |
75a70cf9 | 1191 | new_stmt = gimple_build_assign_with_ops (ABS_EXPR, lhs, rhs, NULL); |
70512b93 | 1192 | |
75a70cf9 | 1193 | gsi = gsi_last_bb (cond_bb); |
1194 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
70512b93 | 1195 | |
1196 | if (negate) | |
1197 | { | |
75a70cf9 | 1198 | /* Get the right GSI. We want to insert after the recently |
70512b93 | 1199 | added ABS_EXPR statement (which we know is the first statement |
1200 | in the block. */ | |
75a70cf9 | 1201 | new_stmt = gimple_build_assign_with_ops (NEGATE_EXPR, result, lhs, NULL); |
70512b93 | 1202 | |
75a70cf9 | 1203 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); |
70512b93 | 1204 | } |
20e5647c | 1205 | |
a4844041 | 1206 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
70512b93 | 1207 | |
1208 | /* Note that we optimized this PHI. */ | |
1209 | return true; | |
1210 | } | |
1211 | ||
e6d0e152 | 1212 | /* Auxiliary functions to determine the set of memory accesses which |
1213 | can't trap because they are preceded by accesses to the same memory | |
182cf5a9 | 1214 | portion. We do that for MEM_REFs, so we only need to track |
e6d0e152 | 1215 | the SSA_NAME of the pointer indirectly referenced. The algorithm |
1216 | simply is a walk over all instructions in dominator order. When | |
182cf5a9 | 1217 | we see an MEM_REF we determine if we've already seen a same |
e6d0e152 | 1218 | ref anywhere up to the root of the dominator tree. If we do the |
af4f74fa | 1219 | current access can't trap. If we don't see any dominating access |
e6d0e152 | 1220 | the current access might trap, but might also make later accesses |
af4f74fa | 1221 | non-trapping, so we remember it. We need to be careful with loads |
1222 | or stores, for instance a load might not trap, while a store would, | |
1223 | so if we see a dominating read access this doesn't mean that a later | |
1224 | write access would not trap. Hence we also need to differentiate the | |
1225 | type of access(es) seen. | |
1226 | ||
1227 | ??? We currently are very conservative and assume that a load might | |
1228 | trap even if a store doesn't (write-only memory). This probably is | |
1229 | overly conservative. */ | |
e6d0e152 | 1230 | |
182cf5a9 | 1231 | /* A hash-table of SSA_NAMEs, and in which basic block an MEM_REF |
e6d0e152 | 1232 | through it was seen, which would constitute a no-trap region for |
1233 | same accesses. */ | |
1234 | struct name_to_bb | |
1235 | { | |
963aee26 | 1236 | unsigned int ssa_name_ver; |
1237 | bool store; | |
1238 | HOST_WIDE_INT offset, size; | |
e6d0e152 | 1239 | basic_block bb; |
1240 | }; | |
1241 | ||
1242 | /* The hash table for remembering what we've seen. */ | |
1243 | static htab_t seen_ssa_names; | |
1244 | ||
182cf5a9 | 1245 | /* The set of MEM_REFs which can't trap. */ |
e6d0e152 | 1246 | static struct pointer_set_t *nontrap_set; |
1247 | ||
963aee26 | 1248 | /* The hash function. */ |
e6d0e152 | 1249 | static hashval_t |
1250 | name_to_bb_hash (const void *p) | |
1251 | { | |
963aee26 | 1252 | const struct name_to_bb *n = (const struct name_to_bb *) p; |
1253 | return n->ssa_name_ver ^ (((hashval_t) n->store) << 31) | |
1254 | ^ (n->offset << 6) ^ (n->size << 3); | |
e6d0e152 | 1255 | } |
1256 | ||
963aee26 | 1257 | /* The equality function of *P1 and *P2. */ |
e6d0e152 | 1258 | static int |
1259 | name_to_bb_eq (const void *p1, const void *p2) | |
1260 | { | |
af4f74fa | 1261 | const struct name_to_bb *n1 = (const struct name_to_bb *)p1; |
1262 | const struct name_to_bb *n2 = (const struct name_to_bb *)p2; | |
e6d0e152 | 1263 | |
963aee26 | 1264 | return n1->ssa_name_ver == n2->ssa_name_ver |
1265 | && n1->store == n2->store | |
1266 | && n1->offset == n2->offset | |
1267 | && n1->size == n2->size; | |
e6d0e152 | 1268 | } |
1269 | ||
f0b5f617 | 1270 | /* We see the expression EXP in basic block BB. If it's an interesting |
182cf5a9 | 1271 | expression (an MEM_REF through an SSA_NAME) possibly insert the |
af4f74fa | 1272 | expression into the set NONTRAP or the hash table of seen expressions. |
1273 | STORE is true if this expression is on the LHS, otherwise it's on | |
1274 | the RHS. */ | |
e6d0e152 | 1275 | static void |
af4f74fa | 1276 | add_or_mark_expr (basic_block bb, tree exp, |
1277 | struct pointer_set_t *nontrap, bool store) | |
e6d0e152 | 1278 | { |
963aee26 | 1279 | HOST_WIDE_INT size; |
1280 | ||
182cf5a9 | 1281 | if (TREE_CODE (exp) == MEM_REF |
963aee26 | 1282 | && TREE_CODE (TREE_OPERAND (exp, 0)) == SSA_NAME |
1283 | && host_integerp (TREE_OPERAND (exp, 1), 0) | |
1284 | && (size = int_size_in_bytes (TREE_TYPE (exp))) > 0) | |
e6d0e152 | 1285 | { |
1286 | tree name = TREE_OPERAND (exp, 0); | |
1287 | struct name_to_bb map; | |
1288 | void **slot; | |
af4f74fa | 1289 | struct name_to_bb *n2bb; |
e6d0e152 | 1290 | basic_block found_bb = 0; |
1291 | ||
182cf5a9 | 1292 | /* Try to find the last seen MEM_REF through the same |
e6d0e152 | 1293 | SSA_NAME, which can trap. */ |
963aee26 | 1294 | map.ssa_name_ver = SSA_NAME_VERSION (name); |
e6d0e152 | 1295 | map.bb = 0; |
af4f74fa | 1296 | map.store = store; |
963aee26 | 1297 | map.offset = tree_low_cst (TREE_OPERAND (exp, 1), 0); |
1298 | map.size = size; | |
1299 | ||
e6d0e152 | 1300 | slot = htab_find_slot (seen_ssa_names, &map, INSERT); |
af4f74fa | 1301 | n2bb = (struct name_to_bb *) *slot; |
1302 | if (n2bb) | |
1303 | found_bb = n2bb->bb; | |
e6d0e152 | 1304 | |
182cf5a9 | 1305 | /* If we've found a trapping MEM_REF, _and_ it dominates EXP |
e6d0e152 | 1306 | (it's in a basic block on the path from us to the dominator root) |
1307 | then we can't trap. */ | |
1308 | if (found_bb && found_bb->aux == (void *)1) | |
1309 | { | |
1310 | pointer_set_insert (nontrap, exp); | |
1311 | } | |
1312 | else | |
1313 | { | |
1314 | /* EXP might trap, so insert it into the hash table. */ | |
af4f74fa | 1315 | if (n2bb) |
e6d0e152 | 1316 | { |
af4f74fa | 1317 | n2bb->bb = bb; |
e6d0e152 | 1318 | } |
1319 | else | |
1320 | { | |
af4f74fa | 1321 | n2bb = XNEW (struct name_to_bb); |
963aee26 | 1322 | n2bb->ssa_name_ver = SSA_NAME_VERSION (name); |
af4f74fa | 1323 | n2bb->bb = bb; |
1324 | n2bb->store = store; | |
963aee26 | 1325 | n2bb->offset = map.offset; |
1326 | n2bb->size = size; | |
af4f74fa | 1327 | *slot = n2bb; |
e6d0e152 | 1328 | } |
1329 | } | |
1330 | } | |
1331 | } | |
1332 | ||
1333 | /* Called by walk_dominator_tree, when entering the block BB. */ | |
1334 | static void | |
1335 | nt_init_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb) | |
1336 | { | |
75a70cf9 | 1337 | gimple_stmt_iterator gsi; |
e6d0e152 | 1338 | /* Mark this BB as being on the path to dominator root. */ |
1339 | bb->aux = (void*)1; | |
1340 | ||
1341 | /* And walk the statements in order. */ | |
75a70cf9 | 1342 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
e6d0e152 | 1343 | { |
75a70cf9 | 1344 | gimple stmt = gsi_stmt (gsi); |
e6d0e152 | 1345 | |
963aee26 | 1346 | if (gimple_assign_single_p (stmt)) |
e6d0e152 | 1347 | { |
75a70cf9 | 1348 | add_or_mark_expr (bb, gimple_assign_lhs (stmt), nontrap_set, true); |
1349 | add_or_mark_expr (bb, gimple_assign_rhs1 (stmt), nontrap_set, false); | |
e6d0e152 | 1350 | } |
1351 | } | |
1352 | } | |
1353 | ||
1354 | /* Called by walk_dominator_tree, when basic block BB is exited. */ | |
1355 | static void | |
1356 | nt_fini_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb) | |
1357 | { | |
1358 | /* This BB isn't on the path to dominator root anymore. */ | |
1359 | bb->aux = NULL; | |
1360 | } | |
1361 | ||
1362 | /* This is the entry point of gathering non trapping memory accesses. | |
1363 | It will do a dominator walk over the whole function, and it will | |
1364 | make use of the bb->aux pointers. It returns a set of trees | |
182cf5a9 | 1365 | (the MEM_REFs itself) which can't trap. */ |
e6d0e152 | 1366 | static struct pointer_set_t * |
1367 | get_non_trapping (void) | |
1368 | { | |
1369 | struct pointer_set_t *nontrap; | |
1370 | struct dom_walk_data walk_data; | |
1371 | ||
1372 | nontrap = pointer_set_create (); | |
1373 | seen_ssa_names = htab_create (128, name_to_bb_hash, name_to_bb_eq, | |
1374 | free); | |
1375 | /* We're going to do a dominator walk, so ensure that we have | |
1376 | dominance information. */ | |
1377 | calculate_dominance_info (CDI_DOMINATORS); | |
1378 | ||
1379 | /* Setup callbacks for the generic dominator tree walker. */ | |
1380 | nontrap_set = nontrap; | |
e6d0e152 | 1381 | walk_data.dom_direction = CDI_DOMINATORS; |
1382 | walk_data.initialize_block_local_data = NULL; | |
6bf320fb | 1383 | walk_data.before_dom_children = nt_init_block; |
1384 | walk_data.after_dom_children = nt_fini_block; | |
e6d0e152 | 1385 | walk_data.global_data = NULL; |
1386 | walk_data.block_local_data_size = 0; | |
e6d0e152 | 1387 | |
1388 | init_walk_dominator_tree (&walk_data); | |
1389 | walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR); | |
1390 | fini_walk_dominator_tree (&walk_data); | |
1391 | htab_delete (seen_ssa_names); | |
1392 | ||
1393 | return nontrap; | |
1394 | } | |
1395 | ||
1396 | /* Do the main work of conditional store replacement. We already know | |
1397 | that the recognized pattern looks like so: | |
1398 | ||
1399 | split: | |
1400 | if (cond) goto MIDDLE_BB; else goto JOIN_BB (edge E1) | |
1401 | MIDDLE_BB: | |
1402 | something | |
1403 | fallthrough (edge E0) | |
1404 | JOIN_BB: | |
1405 | some more | |
1406 | ||
1407 | We check that MIDDLE_BB contains only one store, that that store | |
1408 | doesn't trap (not via NOTRAP, but via checking if an access to the same | |
1409 | memory location dominates us) and that the store has a "simple" RHS. */ | |
1410 | ||
1411 | static bool | |
1412 | cond_store_replacement (basic_block middle_bb, basic_block join_bb, | |
1413 | edge e0, edge e1, struct pointer_set_t *nontrap) | |
1414 | { | |
75a70cf9 | 1415 | gimple assign = last_and_only_stmt (middle_bb); |
03d37e4e | 1416 | tree lhs, rhs, name, name2; |
75a70cf9 | 1417 | gimple newphi, new_stmt; |
1418 | gimple_stmt_iterator gsi; | |
efbcb6de | 1419 | source_location locus; |
e6d0e152 | 1420 | |
1421 | /* Check if middle_bb contains of only one store. */ | |
1422 | if (!assign | |
91cf53d5 | 1423 | || !gimple_assign_single_p (assign)) |
e6d0e152 | 1424 | return false; |
1425 | ||
efbcb6de | 1426 | locus = gimple_location (assign); |
75a70cf9 | 1427 | lhs = gimple_assign_lhs (assign); |
1428 | rhs = gimple_assign_rhs1 (assign); | |
182cf5a9 | 1429 | if (TREE_CODE (lhs) != MEM_REF |
91cf53d5 | 1430 | || TREE_CODE (TREE_OPERAND (lhs, 0)) != SSA_NAME |
3211fa0a | 1431 | || !is_gimple_reg_type (TREE_TYPE (lhs))) |
e6d0e152 | 1432 | return false; |
91cf53d5 | 1433 | |
e6d0e152 | 1434 | /* Prove that we can move the store down. We could also check |
1435 | TREE_THIS_NOTRAP here, but in that case we also could move stores, | |
1436 | whose value is not available readily, which we want to avoid. */ | |
1437 | if (!pointer_set_contains (nontrap, lhs)) | |
1438 | return false; | |
1439 | ||
1440 | /* Now we've checked the constraints, so do the transformation: | |
1441 | 1) Remove the single store. */ | |
75a70cf9 | 1442 | gsi = gsi_for_stmt (assign); |
3211fa0a | 1443 | unlink_stmt_vdef (assign); |
75a70cf9 | 1444 | gsi_remove (&gsi, true); |
91cf53d5 | 1445 | release_defs (assign); |
e6d0e152 | 1446 | |
03d37e4e | 1447 | /* 2) Insert a load from the memory of the store to the temporary |
e6d0e152 | 1448 | on the edge which did not contain the store. */ |
1449 | lhs = unshare_expr (lhs); | |
03d37e4e | 1450 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1451 | new_stmt = gimple_build_assign (name, lhs); | |
efbcb6de | 1452 | gimple_set_location (new_stmt, locus); |
75a70cf9 | 1453 | gsi_insert_on_edge (e1, new_stmt); |
e6d0e152 | 1454 | |
03d37e4e | 1455 | /* 3) Create a PHI node at the join block, with one argument |
e6d0e152 | 1456 | holding the old RHS, and the other holding the temporary |
1457 | where we stored the old memory contents. */ | |
03d37e4e | 1458 | name2 = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1459 | newphi = create_phi_node (name2, join_bb); | |
60d535d2 | 1460 | add_phi_arg (newphi, rhs, e0, locus); |
1461 | add_phi_arg (newphi, name, e1, locus); | |
e6d0e152 | 1462 | |
1463 | lhs = unshare_expr (lhs); | |
75a70cf9 | 1464 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); |
e6d0e152 | 1465 | |
03d37e4e | 1466 | /* 4) Insert that PHI node. */ |
75a70cf9 | 1467 | gsi = gsi_after_labels (join_bb); |
1468 | if (gsi_end_p (gsi)) | |
e6d0e152 | 1469 | { |
75a70cf9 | 1470 | gsi = gsi_last_bb (join_bb); |
1471 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
e6d0e152 | 1472 | } |
1473 | else | |
75a70cf9 | 1474 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); |
e6d0e152 | 1475 | |
1476 | return true; | |
1477 | } | |
4ee9c684 | 1478 | |
ec611e12 | 1479 | /* Do the main work of conditional store replacement. */ |
91cf53d5 | 1480 | |
1481 | static bool | |
ec611e12 | 1482 | cond_if_else_store_replacement_1 (basic_block then_bb, basic_block else_bb, |
1483 | basic_block join_bb, gimple then_assign, | |
1484 | gimple else_assign) | |
91cf53d5 | 1485 | { |
03d37e4e | 1486 | tree lhs_base, lhs, then_rhs, else_rhs, name; |
91cf53d5 | 1487 | source_location then_locus, else_locus; |
1488 | gimple_stmt_iterator gsi; | |
1489 | gimple newphi, new_stmt; | |
1490 | ||
91cf53d5 | 1491 | if (then_assign == NULL |
1492 | || !gimple_assign_single_p (then_assign) | |
3c25489e | 1493 | || gimple_clobber_p (then_assign) |
91cf53d5 | 1494 | || else_assign == NULL |
3c25489e | 1495 | || !gimple_assign_single_p (else_assign) |
1496 | || gimple_clobber_p (else_assign)) | |
91cf53d5 | 1497 | return false; |
1498 | ||
1499 | lhs = gimple_assign_lhs (then_assign); | |
1500 | if (!is_gimple_reg_type (TREE_TYPE (lhs)) | |
1501 | || !operand_equal_p (lhs, gimple_assign_lhs (else_assign), 0)) | |
1502 | return false; | |
1503 | ||
1504 | lhs_base = get_base_address (lhs); | |
1505 | if (lhs_base == NULL_TREE | |
1506 | || (!DECL_P (lhs_base) && TREE_CODE (lhs_base) != MEM_REF)) | |
1507 | return false; | |
1508 | ||
1509 | then_rhs = gimple_assign_rhs1 (then_assign); | |
1510 | else_rhs = gimple_assign_rhs1 (else_assign); | |
1511 | then_locus = gimple_location (then_assign); | |
1512 | else_locus = gimple_location (else_assign); | |
1513 | ||
1514 | /* Now we've checked the constraints, so do the transformation: | |
1515 | 1) Remove the stores. */ | |
1516 | gsi = gsi_for_stmt (then_assign); | |
1517 | unlink_stmt_vdef (then_assign); | |
1518 | gsi_remove (&gsi, true); | |
1519 | release_defs (then_assign); | |
1520 | ||
1521 | gsi = gsi_for_stmt (else_assign); | |
1522 | unlink_stmt_vdef (else_assign); | |
1523 | gsi_remove (&gsi, true); | |
1524 | release_defs (else_assign); | |
1525 | ||
03d37e4e | 1526 | /* 2) Create a PHI node at the join block, with one argument |
91cf53d5 | 1527 | holding the old RHS, and the other holding the temporary |
1528 | where we stored the old memory contents. */ | |
03d37e4e | 1529 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1530 | newphi = create_phi_node (name, join_bb); | |
60d535d2 | 1531 | add_phi_arg (newphi, then_rhs, EDGE_SUCC (then_bb, 0), then_locus); |
1532 | add_phi_arg (newphi, else_rhs, EDGE_SUCC (else_bb, 0), else_locus); | |
91cf53d5 | 1533 | |
1534 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); | |
1535 | ||
03d37e4e | 1536 | /* 3) Insert that PHI node. */ |
91cf53d5 | 1537 | gsi = gsi_after_labels (join_bb); |
1538 | if (gsi_end_p (gsi)) | |
1539 | { | |
1540 | gsi = gsi_last_bb (join_bb); | |
1541 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
1542 | } | |
1543 | else | |
1544 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
1545 | ||
1546 | return true; | |
1547 | } | |
1548 | ||
ec611e12 | 1549 | /* Conditional store replacement. We already know |
1550 | that the recognized pattern looks like so: | |
1551 | ||
1552 | split: | |
1553 | if (cond) goto THEN_BB; else goto ELSE_BB (edge E1) | |
1554 | THEN_BB: | |
1555 | ... | |
1556 | X = Y; | |
1557 | ... | |
1558 | goto JOIN_BB; | |
1559 | ELSE_BB: | |
1560 | ... | |
1561 | X = Z; | |
1562 | ... | |
1563 | fallthrough (edge E0) | |
1564 | JOIN_BB: | |
1565 | some more | |
1566 | ||
1567 | We check that it is safe to sink the store to JOIN_BB by verifying that | |
1568 | there are no read-after-write or write-after-write dependencies in | |
1569 | THEN_BB and ELSE_BB. */ | |
1570 | ||
1571 | static bool | |
1572 | cond_if_else_store_replacement (basic_block then_bb, basic_block else_bb, | |
1573 | basic_block join_bb) | |
1574 | { | |
1575 | gimple then_assign = last_and_only_stmt (then_bb); | |
1576 | gimple else_assign = last_and_only_stmt (else_bb); | |
1577 | VEC (data_reference_p, heap) *then_datarefs, *else_datarefs; | |
1578 | VEC (ddr_p, heap) *then_ddrs, *else_ddrs; | |
1579 | gimple then_store, else_store; | |
1580 | bool found, ok = false, res; | |
1581 | struct data_dependence_relation *ddr; | |
1582 | data_reference_p then_dr, else_dr; | |
1583 | int i, j; | |
1584 | tree then_lhs, else_lhs; | |
1585 | VEC (gimple, heap) *then_stores, *else_stores; | |
1586 | basic_block blocks[3]; | |
1587 | ||
1588 | if (MAX_STORES_TO_SINK == 0) | |
1589 | return false; | |
1590 | ||
1591 | /* Handle the case with single statement in THEN_BB and ELSE_BB. */ | |
1592 | if (then_assign && else_assign) | |
1593 | return cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, | |
1594 | then_assign, else_assign); | |
1595 | ||
1596 | /* Find data references. */ | |
1597 | then_datarefs = VEC_alloc (data_reference_p, heap, 1); | |
1598 | else_datarefs = VEC_alloc (data_reference_p, heap, 1); | |
1599 | if ((find_data_references_in_bb (NULL, then_bb, &then_datarefs) | |
1600 | == chrec_dont_know) | |
1601 | || !VEC_length (data_reference_p, then_datarefs) | |
1602 | || (find_data_references_in_bb (NULL, else_bb, &else_datarefs) | |
1603 | == chrec_dont_know) | |
1604 | || !VEC_length (data_reference_p, else_datarefs)) | |
1605 | { | |
1606 | free_data_refs (then_datarefs); | |
1607 | free_data_refs (else_datarefs); | |
1608 | return false; | |
1609 | } | |
1610 | ||
1611 | /* Find pairs of stores with equal LHS. */ | |
1612 | then_stores = VEC_alloc (gimple, heap, 1); | |
1613 | else_stores = VEC_alloc (gimple, heap, 1); | |
1614 | FOR_EACH_VEC_ELT (data_reference_p, then_datarefs, i, then_dr) | |
1615 | { | |
1616 | if (DR_IS_READ (then_dr)) | |
1617 | continue; | |
1618 | ||
1619 | then_store = DR_STMT (then_dr); | |
728dcc71 | 1620 | then_lhs = gimple_get_lhs (then_store); |
ec611e12 | 1621 | found = false; |
1622 | ||
1623 | FOR_EACH_VEC_ELT (data_reference_p, else_datarefs, j, else_dr) | |
1624 | { | |
1625 | if (DR_IS_READ (else_dr)) | |
1626 | continue; | |
1627 | ||
1628 | else_store = DR_STMT (else_dr); | |
728dcc71 | 1629 | else_lhs = gimple_get_lhs (else_store); |
ec611e12 | 1630 | |
1631 | if (operand_equal_p (then_lhs, else_lhs, 0)) | |
1632 | { | |
1633 | found = true; | |
1634 | break; | |
1635 | } | |
1636 | } | |
1637 | ||
1638 | if (!found) | |
1639 | continue; | |
1640 | ||
1641 | VEC_safe_push (gimple, heap, then_stores, then_store); | |
1642 | VEC_safe_push (gimple, heap, else_stores, else_store); | |
1643 | } | |
1644 | ||
1645 | /* No pairs of stores found. */ | |
1646 | if (!VEC_length (gimple, then_stores) | |
1647 | || VEC_length (gimple, then_stores) > (unsigned) MAX_STORES_TO_SINK) | |
1648 | { | |
1649 | free_data_refs (then_datarefs); | |
1650 | free_data_refs (else_datarefs); | |
1651 | VEC_free (gimple, heap, then_stores); | |
1652 | VEC_free (gimple, heap, else_stores); | |
1653 | return false; | |
1654 | } | |
1655 | ||
1656 | /* Compute and check data dependencies in both basic blocks. */ | |
1657 | then_ddrs = VEC_alloc (ddr_p, heap, 1); | |
1658 | else_ddrs = VEC_alloc (ddr_p, heap, 1); | |
8b3fb720 | 1659 | if (!compute_all_dependences (then_datarefs, &then_ddrs, NULL, false) |
1660 | || !compute_all_dependences (else_datarefs, &else_ddrs, NULL, false)) | |
1661 | { | |
1662 | free_dependence_relations (then_ddrs); | |
1663 | free_dependence_relations (else_ddrs); | |
1664 | free_data_refs (then_datarefs); | |
1665 | free_data_refs (else_datarefs); | |
1666 | VEC_free (gimple, heap, then_stores); | |
1667 | VEC_free (gimple, heap, else_stores); | |
1668 | return false; | |
1669 | } | |
ec611e12 | 1670 | blocks[0] = then_bb; |
1671 | blocks[1] = else_bb; | |
1672 | blocks[2] = join_bb; | |
1673 | renumber_gimple_stmt_uids_in_blocks (blocks, 3); | |
1674 | ||
1675 | /* Check that there are no read-after-write or write-after-write dependencies | |
1676 | in THEN_BB. */ | |
1677 | FOR_EACH_VEC_ELT (ddr_p, then_ddrs, i, ddr) | |
1678 | { | |
1679 | struct data_reference *dra = DDR_A (ddr); | |
1680 | struct data_reference *drb = DDR_B (ddr); | |
1681 | ||
1682 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
1683 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
1684 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
1685 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
1686 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
1687 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
1688 | { | |
1689 | free_dependence_relations (then_ddrs); | |
1690 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1691 | free_data_refs (then_datarefs); |
1692 | free_data_refs (else_datarefs); | |
ec611e12 | 1693 | VEC_free (gimple, heap, then_stores); |
1694 | VEC_free (gimple, heap, else_stores); | |
1695 | return false; | |
1696 | } | |
1697 | } | |
1698 | ||
1699 | /* Check that there are no read-after-write or write-after-write dependencies | |
1700 | in ELSE_BB. */ | |
1701 | FOR_EACH_VEC_ELT (ddr_p, else_ddrs, i, ddr) | |
1702 | { | |
1703 | struct data_reference *dra = DDR_A (ddr); | |
1704 | struct data_reference *drb = DDR_B (ddr); | |
1705 | ||
1706 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
1707 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
1708 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
1709 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
1710 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
1711 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
1712 | { | |
1713 | free_dependence_relations (then_ddrs); | |
1714 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1715 | free_data_refs (then_datarefs); |
1716 | free_data_refs (else_datarefs); | |
ec611e12 | 1717 | VEC_free (gimple, heap, then_stores); |
1718 | VEC_free (gimple, heap, else_stores); | |
1719 | return false; | |
1720 | } | |
1721 | } | |
1722 | ||
1723 | /* Sink stores with same LHS. */ | |
1724 | FOR_EACH_VEC_ELT (gimple, then_stores, i, then_store) | |
1725 | { | |
1726 | else_store = VEC_index (gimple, else_stores, i); | |
1727 | res = cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, | |
1728 | then_store, else_store); | |
1729 | ok = ok || res; | |
1730 | } | |
1731 | ||
1732 | free_dependence_relations (then_ddrs); | |
1733 | free_dependence_relations (else_ddrs); | |
2473bfb7 | 1734 | free_data_refs (then_datarefs); |
1735 | free_data_refs (else_datarefs); | |
ec611e12 | 1736 | VEC_free (gimple, heap, then_stores); |
1737 | VEC_free (gimple, heap, else_stores); | |
1738 | ||
1739 | return ok; | |
1740 | } | |
1741 | ||
239e9670 | 1742 | /* Return TRUE if STMT has a VUSE whose corresponding VDEF is in BB. */ |
1743 | ||
1744 | static bool | |
1745 | local_mem_dependence (gimple stmt, basic_block bb) | |
1746 | { | |
1747 | tree vuse = gimple_vuse (stmt); | |
1748 | gimple def; | |
1749 | ||
1750 | if (!vuse) | |
1751 | return false; | |
1752 | ||
1753 | def = SSA_NAME_DEF_STMT (vuse); | |
1754 | return (def && gimple_bb (def) == bb); | |
1755 | } | |
1756 | ||
1757 | /* Given a "diamond" control-flow pattern where BB0 tests a condition, | |
1758 | BB1 and BB2 are "then" and "else" blocks dependent on this test, | |
1759 | and BB3 rejoins control flow following BB1 and BB2, look for | |
1760 | opportunities to hoist loads as follows. If BB3 contains a PHI of | |
1761 | two loads, one each occurring in BB1 and BB2, and the loads are | |
1762 | provably of adjacent fields in the same structure, then move both | |
1763 | loads into BB0. Of course this can only be done if there are no | |
1764 | dependencies preventing such motion. | |
1765 | ||
1766 | One of the hoisted loads will always be speculative, so the | |
1767 | transformation is currently conservative: | |
1768 | ||
1769 | - The fields must be strictly adjacent. | |
1770 | - The two fields must occupy a single memory block that is | |
1771 | guaranteed to not cross a page boundary. | |
1772 | ||
1773 | The last is difficult to prove, as such memory blocks should be | |
1774 | aligned on the minimum of the stack alignment boundary and the | |
1775 | alignment guaranteed by heap allocation interfaces. Thus we rely | |
1776 | on a parameter for the alignment value. | |
1777 | ||
1778 | Provided a good value is used for the last case, the first | |
1779 | restriction could possibly be relaxed. */ | |
1780 | ||
1781 | static void | |
1782 | hoist_adjacent_loads (basic_block bb0, basic_block bb1, | |
1783 | basic_block bb2, basic_block bb3) | |
1784 | { | |
1785 | int param_align = PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE); | |
1786 | unsigned param_align_bits = (unsigned) (param_align * BITS_PER_UNIT); | |
1787 | gimple_stmt_iterator gsi; | |
1788 | ||
1789 | /* Walk the phis in bb3 looking for an opportunity. We are looking | |
1790 | for phis of two SSA names, one each of which is defined in bb1 and | |
1791 | bb2. */ | |
1792 | for (gsi = gsi_start_phis (bb3); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1793 | { | |
1794 | gimple phi_stmt = gsi_stmt (gsi); | |
1795 | gimple def1, def2, defswap; | |
1796 | tree arg1, arg2, ref1, ref2, field1, field2, fieldswap; | |
1797 | tree tree_offset1, tree_offset2, tree_size2, next; | |
1798 | int offset1, offset2, size2; | |
1799 | unsigned align1; | |
1800 | gimple_stmt_iterator gsi2; | |
1801 | basic_block bb_for_def1, bb_for_def2; | |
1802 | ||
7c782c9b | 1803 | if (gimple_phi_num_args (phi_stmt) != 2 |
1804 | || virtual_operand_p (gimple_phi_result (phi_stmt))) | |
239e9670 | 1805 | continue; |
1806 | ||
1807 | arg1 = gimple_phi_arg_def (phi_stmt, 0); | |
1808 | arg2 = gimple_phi_arg_def (phi_stmt, 1); | |
1809 | ||
1810 | if (TREE_CODE (arg1) != SSA_NAME | |
1811 | || TREE_CODE (arg2) != SSA_NAME | |
1812 | || SSA_NAME_IS_DEFAULT_DEF (arg1) | |
7c782c9b | 1813 | || SSA_NAME_IS_DEFAULT_DEF (arg2)) |
239e9670 | 1814 | continue; |
1815 | ||
1816 | def1 = SSA_NAME_DEF_STMT (arg1); | |
1817 | def2 = SSA_NAME_DEF_STMT (arg2); | |
1818 | ||
1819 | if ((gimple_bb (def1) != bb1 || gimple_bb (def2) != bb2) | |
1820 | && (gimple_bb (def2) != bb1 || gimple_bb (def1) != bb2)) | |
1821 | continue; | |
1822 | ||
1823 | /* Check the mode of the arguments to be sure a conditional move | |
1824 | can be generated for it. */ | |
935611bc | 1825 | if (optab_handler (movcc_optab, TYPE_MODE (TREE_TYPE (arg1))) |
1826 | == CODE_FOR_nothing) | |
239e9670 | 1827 | continue; |
1828 | ||
1829 | /* Both statements must be assignments whose RHS is a COMPONENT_REF. */ | |
1830 | if (!gimple_assign_single_p (def1) | |
1831 | || !gimple_assign_single_p (def2)) | |
1832 | continue; | |
1833 | ||
1834 | ref1 = gimple_assign_rhs1 (def1); | |
1835 | ref2 = gimple_assign_rhs1 (def2); | |
1836 | ||
1837 | if (TREE_CODE (ref1) != COMPONENT_REF | |
1838 | || TREE_CODE (ref2) != COMPONENT_REF) | |
1839 | continue; | |
1840 | ||
1841 | /* The zeroth operand of the two component references must be | |
1842 | identical. It is not sufficient to compare get_base_address of | |
1843 | the two references, because this could allow for different | |
1844 | elements of the same array in the two trees. It is not safe to | |
1845 | assume that the existence of one array element implies the | |
1846 | existence of a different one. */ | |
1847 | if (!operand_equal_p (TREE_OPERAND (ref1, 0), TREE_OPERAND (ref2, 0), 0)) | |
1848 | continue; | |
1849 | ||
1850 | field1 = TREE_OPERAND (ref1, 1); | |
1851 | field2 = TREE_OPERAND (ref2, 1); | |
1852 | ||
1853 | /* Check for field adjacency, and ensure field1 comes first. */ | |
1854 | for (next = DECL_CHAIN (field1); | |
1855 | next && TREE_CODE (next) != FIELD_DECL; | |
1856 | next = DECL_CHAIN (next)) | |
1857 | ; | |
1858 | ||
1859 | if (next != field2) | |
1860 | { | |
1861 | for (next = DECL_CHAIN (field2); | |
1862 | next && TREE_CODE (next) != FIELD_DECL; | |
1863 | next = DECL_CHAIN (next)) | |
1864 | ; | |
1865 | ||
1866 | if (next != field1) | |
1867 | continue; | |
1868 | ||
1869 | fieldswap = field1; | |
1870 | field1 = field2; | |
1871 | field2 = fieldswap; | |
1872 | defswap = def1; | |
1873 | def1 = def2; | |
1874 | def2 = defswap; | |
239e9670 | 1875 | } |
1876 | ||
7c74ee50 | 1877 | bb_for_def1 = gimple_bb (def1); |
1878 | bb_for_def2 = gimple_bb (def2); | |
1879 | ||
239e9670 | 1880 | /* Check for proper alignment of the first field. */ |
1881 | tree_offset1 = bit_position (field1); | |
1882 | tree_offset2 = bit_position (field2); | |
1883 | tree_size2 = DECL_SIZE (field2); | |
1884 | ||
1885 | if (!host_integerp (tree_offset1, 1) | |
1886 | || !host_integerp (tree_offset2, 1) | |
1887 | || !host_integerp (tree_size2, 1)) | |
1888 | continue; | |
1889 | ||
1890 | offset1 = TREE_INT_CST_LOW (tree_offset1); | |
1891 | offset2 = TREE_INT_CST_LOW (tree_offset2); | |
1892 | size2 = TREE_INT_CST_LOW (tree_size2); | |
1893 | align1 = DECL_ALIGN (field1) % param_align_bits; | |
1894 | ||
1895 | if (offset1 % BITS_PER_UNIT != 0) | |
1896 | continue; | |
1897 | ||
1898 | /* For profitability, the two field references should fit within | |
1899 | a single cache line. */ | |
1900 | if (align1 + offset2 - offset1 + size2 > param_align_bits) | |
1901 | continue; | |
1902 | ||
1903 | /* The two expressions cannot be dependent upon vdefs defined | |
1904 | in bb1/bb2. */ | |
1905 | if (local_mem_dependence (def1, bb_for_def1) | |
1906 | || local_mem_dependence (def2, bb_for_def2)) | |
1907 | continue; | |
1908 | ||
1909 | /* The conditions are satisfied; hoist the loads from bb1 and bb2 into | |
1910 | bb0. We hoist the first one first so that a cache miss is handled | |
1911 | efficiently regardless of hardware cache-fill policy. */ | |
1912 | gsi2 = gsi_for_stmt (def1); | |
1913 | gsi_move_to_bb_end (&gsi2, bb0); | |
1914 | gsi2 = gsi_for_stmt (def2); | |
1915 | gsi_move_to_bb_end (&gsi2, bb0); | |
1916 | ||
1917 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1918 | { | |
1919 | fprintf (dump_file, | |
1920 | "\nHoisting adjacent loads from %d and %d into %d: \n", | |
1921 | bb_for_def1->index, bb_for_def2->index, bb0->index); | |
1922 | print_gimple_stmt (dump_file, def1, 0, TDF_VOPS|TDF_MEMSYMS); | |
1923 | print_gimple_stmt (dump_file, def2, 0, TDF_VOPS|TDF_MEMSYMS); | |
1924 | } | |
1925 | } | |
1926 | } | |
1927 | ||
1928 | /* Determine whether we should attempt to hoist adjacent loads out of | |
1929 | diamond patterns in pass_phiopt. Always hoist loads if | |
1930 | -fhoist-adjacent-loads is specified and the target machine has | |
6f0ddab1 | 1931 | both a conditional move instruction and a defined cache line size. */ |
239e9670 | 1932 | |
1933 | static bool | |
1934 | gate_hoist_loads (void) | |
1935 | { | |
6f0ddab1 | 1936 | return (flag_hoist_adjacent_loads == 1 |
1937 | && PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE) | |
1938 | && HAVE_conditional_move); | |
239e9670 | 1939 | } |
1940 | ||
4ee9c684 | 1941 | /* Always do these optimizations if we have SSA |
20e5647c | 1942 | trees to work on. */ |
4ee9c684 | 1943 | static bool |
1944 | gate_phiopt (void) | |
1945 | { | |
1946 | return 1; | |
1947 | } | |
20e5647c | 1948 | |
20099e35 | 1949 | struct gimple_opt_pass pass_phiopt = |
4ee9c684 | 1950 | { |
20099e35 | 1951 | { |
1952 | GIMPLE_PASS, | |
4ee9c684 | 1953 | "phiopt", /* name */ |
1954 | gate_phiopt, /* gate */ | |
1955 | tree_ssa_phiopt, /* execute */ | |
1956 | NULL, /* sub */ | |
1957 | NULL, /* next */ | |
1958 | 0, /* static_pass_number */ | |
1959 | TV_TREE_PHIOPT, /* tv_id */ | |
2f8eb909 | 1960 | PROP_cfg | PROP_ssa, /* properties_required */ |
4ee9c684 | 1961 | 0, /* properties_provided */ |
1962 | 0, /* properties_destroyed */ | |
1963 | 0, /* todo_flags_start */ | |
771e2890 | 1964 | TODO_ggc_collect |
88dbf20f | 1965 | | TODO_verify_ssa |
88dbf20f | 1966 | | TODO_verify_flow |
20099e35 | 1967 | | TODO_verify_stmts /* todo_flags_finish */ |
1968 | } | |
4ee9c684 | 1969 | }; |
e6d0e152 | 1970 | |
1971 | static bool | |
1972 | gate_cselim (void) | |
1973 | { | |
1974 | return flag_tree_cselim; | |
1975 | } | |
1976 | ||
20099e35 | 1977 | struct gimple_opt_pass pass_cselim = |
e6d0e152 | 1978 | { |
20099e35 | 1979 | { |
1980 | GIMPLE_PASS, | |
e6d0e152 | 1981 | "cselim", /* name */ |
1982 | gate_cselim, /* gate */ | |
1983 | tree_ssa_cs_elim, /* execute */ | |
1984 | NULL, /* sub */ | |
1985 | NULL, /* next */ | |
1986 | 0, /* static_pass_number */ | |
1987 | TV_TREE_PHIOPT, /* tv_id */ | |
2f8eb909 | 1988 | PROP_cfg | PROP_ssa, /* properties_required */ |
e6d0e152 | 1989 | 0, /* properties_provided */ |
1990 | 0, /* properties_destroyed */ | |
1991 | 0, /* todo_flags_start */ | |
771e2890 | 1992 | TODO_ggc_collect |
e6d0e152 | 1993 | | TODO_verify_ssa |
1994 | | TODO_verify_flow | |
20099e35 | 1995 | | TODO_verify_stmts /* todo_flags_finish */ |
1996 | } | |
e6d0e152 | 1997 | }; |