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6de9cd9a | 1 | /* Optimization of PHI nodes by converting them into straightline code. |
cbe34bb5 | 2 | Copyright (C) 2004-2017 Free Software Foundation, Inc. |
6de9cd9a DN |
3 | |
4 | This file is part of GCC. | |
0385f644 | 5 | |
6de9cd9a DN |
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 | |
9dcd6f09 | 8 | Free Software Foundation; either version 3, or (at your option) any |
6de9cd9a | 9 | later version. |
0385f644 | 10 | |
6de9cd9a DN |
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. | |
0385f644 | 15 | |
6de9cd9a | 16 | You should have received a copy of the GNU General Public License |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
6de9cd9a DN |
19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
c7131fb2 | 23 | #include "backend.h" |
957060b5 AM |
24 | #include "insn-codes.h" |
25 | #include "rtl.h" | |
6de9cd9a | 26 | #include "tree.h" |
c7131fb2 | 27 | #include "gimple.h" |
957060b5 AM |
28 | #include "cfghooks.h" |
29 | #include "tree-pass.h" | |
c7131fb2 | 30 | #include "ssa.h" |
957060b5 AM |
31 | #include "optabs-tree.h" |
32 | #include "insn-config.h" | |
33 | #include "gimple-pretty-print.h" | |
40e23961 | 34 | #include "fold-const.h" |
d8a2d370 | 35 | #include "stor-layout.h" |
60393bbc | 36 | #include "cfganal.h" |
45b0be94 | 37 | #include "gimplify.h" |
5be5c238 | 38 | #include "gimple-iterator.h" |
18f429e2 | 39 | #include "gimplify-me.h" |
442b4905 | 40 | #include "tree-cfg.h" |
442b4905 | 41 | #include "tree-dfa.h" |
a5828d1e | 42 | #include "domwalk.h" |
bfe068c3 IR |
43 | #include "cfgloop.h" |
44 | #include "tree-data-ref.h" | |
a9e0d843 | 45 | #include "tree-scalar-evolution.h" |
421bf780 | 46 | #include "tree-inline.h" |
49b8fe6c | 47 | #include "params.h" |
372a6eb8 | 48 | |
372a6eb8 | 49 | static unsigned int tree_ssa_phiopt_worker (bool, bool); |
e5206274 | 50 | static bool conditional_replacement (basic_block, basic_block, |
538dd0b7 | 51 | edge, edge, gphi *, tree, tree); |
cfd719e7 JJ |
52 | static gphi *factor_out_conditional_conversion (edge, edge, gphi *, tree, tree, |
53 | gimple *); | |
210ac0b7 | 54 | static int value_replacement (basic_block, basic_block, |
355fe088 | 55 | edge, edge, gimple *, tree, tree); |
e5206274 | 56 | static bool minmax_replacement (basic_block, basic_block, |
355fe088 | 57 | edge, edge, gimple *, tree, tree); |
e5206274 | 58 | static bool abs_replacement (basic_block, basic_block, |
355fe088 | 59 | edge, edge, gimple *, tree, tree); |
a5828d1e | 60 | static bool cond_store_replacement (basic_block, basic_block, edge, edge, |
6e2830c3 | 61 | hash_set<tree> *); |
23782cc3 | 62 | static bool cond_if_else_store_replacement (basic_block, basic_block, basic_block); |
6e2830c3 | 63 | static hash_set<tree> * get_non_trapping (); |
355fe088 | 64 | static void replace_phi_edge_with_variable (basic_block, edge, gimple *, tree); |
372a6eb8 BS |
65 | static void hoist_adjacent_loads (basic_block, basic_block, |
66 | basic_block, basic_block); | |
67 | static bool gate_hoist_loads (void); | |
1833df5c | 68 | |
a5828d1e MM |
69 | /* This pass tries to transform conditional stores into unconditional |
70 | ones, enabling further simplifications with the simpler then and else | |
71 | blocks. In particular it replaces this: | |
72 | ||
73 | bb0: | |
74 | if (cond) goto bb2; else goto bb1; | |
75 | bb1: | |
23782cc3 | 76 | *p = RHS; |
a5828d1e MM |
77 | bb2: |
78 | ||
79 | with | |
80 | ||
81 | bb0: | |
82 | if (cond) goto bb1; else goto bb2; | |
83 | bb1: | |
84 | condtmp' = *p; | |
85 | bb2: | |
86 | condtmp = PHI <RHS, condtmp'> | |
23782cc3 | 87 | *p = condtmp; |
a5828d1e MM |
88 | |
89 | This transformation can only be done under several constraints, | |
23782cc3 JJ |
90 | documented below. It also replaces: |
91 | ||
92 | bb0: | |
93 | if (cond) goto bb2; else goto bb1; | |
94 | bb1: | |
95 | *p = RHS1; | |
96 | goto bb3; | |
97 | bb2: | |
98 | *p = RHS2; | |
99 | bb3: | |
100 | ||
101 | with | |
102 | ||
103 | bb0: | |
104 | if (cond) goto bb3; else goto bb1; | |
105 | bb1: | |
106 | bb3: | |
107 | condtmp = PHI <RHS1, RHS2> | |
108 | *p = condtmp; */ | |
a5828d1e MM |
109 | |
110 | static unsigned int | |
111 | tree_ssa_cs_elim (void) | |
112 | { | |
a9e0d843 RB |
113 | unsigned todo; |
114 | /* ??? We are not interested in loop related info, but the following | |
115 | will create it, ICEing as we didn't init loops with pre-headers. | |
116 | An interfacing issue of find_data_references_in_bb. */ | |
117 | loop_optimizer_init (LOOPS_NORMAL); | |
118 | scev_initialize (); | |
119 | todo = tree_ssa_phiopt_worker (true, false); | |
120 | scev_finalize (); | |
121 | loop_optimizer_finalize (); | |
122 | return todo; | |
a5828d1e MM |
123 | } |
124 | ||
b928d32b AP |
125 | /* Return the singleton PHI in the SEQ of PHIs for edges E0 and E1. */ |
126 | ||
538dd0b7 | 127 | static gphi * |
b928d32b AP |
128 | single_non_singleton_phi_for_edges (gimple_seq seq, edge e0, edge e1) |
129 | { | |
130 | gimple_stmt_iterator i; | |
538dd0b7 | 131 | gphi *phi = NULL; |
b928d32b | 132 | if (gimple_seq_singleton_p (seq)) |
538dd0b7 | 133 | return as_a <gphi *> (gsi_stmt (gsi_start (seq))); |
b928d32b AP |
134 | for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i)) |
135 | { | |
538dd0b7 | 136 | gphi *p = as_a <gphi *> (gsi_stmt (i)); |
b928d32b AP |
137 | /* If the PHI arguments are equal then we can skip this PHI. */ |
138 | if (operand_equal_for_phi_arg_p (gimple_phi_arg_def (p, e0->dest_idx), | |
139 | gimple_phi_arg_def (p, e1->dest_idx))) | |
140 | continue; | |
141 | ||
142 | /* If we already have a PHI that has the two edge arguments are | |
143 | different, then return it is not a singleton for these PHIs. */ | |
144 | if (phi) | |
145 | return NULL; | |
146 | ||
147 | phi = p; | |
148 | } | |
149 | return phi; | |
150 | } | |
151 | ||
a5828d1e MM |
152 | /* The core routine of conditional store replacement and normal |
153 | phi optimizations. Both share much of the infrastructure in how | |
154 | to match applicable basic block patterns. DO_STORE_ELIM is true | |
372a6eb8 | 155 | when we want to do conditional store replacement, false otherwise. |
c9ef86a1 | 156 | DO_HOIST_LOADS is true when we want to hoist adjacent loads out |
372a6eb8 | 157 | of diamond control flow patterns, false otherwise. */ |
a5828d1e | 158 | static unsigned int |
372a6eb8 | 159 | tree_ssa_phiopt_worker (bool do_store_elim, bool do_hoist_loads) |
6de9cd9a DN |
160 | { |
161 | basic_block bb; | |
8eaa0f34 ZD |
162 | basic_block *bb_order; |
163 | unsigned n, i; | |
3e0a08d7 | 164 | bool cfgchanged = false; |
6e2830c3 | 165 | hash_set<tree> *nontrap = 0; |
a5828d1e MM |
166 | |
167 | if (do_store_elim) | |
83d5977e RG |
168 | /* Calculate the set of non-trapping memory accesses. */ |
169 | nontrap = get_non_trapping (); | |
8eaa0f34 ZD |
170 | |
171 | /* Search every basic block for COND_EXPR we may be able to optimize. | |
172 | ||
173 | We walk the blocks in order that guarantees that a block with | |
174 | a single predecessor is processed before the predecessor. | |
175 | This ensures that we collapse inner ifs before visiting the | |
176 | outer ones, and also that we do not try to visit a removed | |
177 | block. */ | |
3d9c733e | 178 | bb_order = single_pred_before_succ_order (); |
0cae8d31 | 179 | n = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; |
6de9cd9a | 180 | |
b8698a0f | 181 | for (i = 0; i < n; i++) |
6de9cd9a | 182 | { |
355fe088 | 183 | gimple *cond_stmt; |
538dd0b7 | 184 | gphi *phi; |
80c4ed35 AP |
185 | basic_block bb1, bb2; |
186 | edge e1, e2; | |
8eaa0f34 ZD |
187 | tree arg0, arg1; |
188 | ||
189 | bb = bb_order[i]; | |
0385f644 | 190 | |
726a989a RB |
191 | cond_stmt = last_stmt (bb); |
192 | /* Check to see if the last statement is a GIMPLE_COND. */ | |
193 | if (!cond_stmt | |
194 | || gimple_code (cond_stmt) != GIMPLE_COND) | |
80c4ed35 | 195 | continue; |
0385f644 | 196 | |
80c4ed35 AP |
197 | e1 = EDGE_SUCC (bb, 0); |
198 | bb1 = e1->dest; | |
199 | e2 = EDGE_SUCC (bb, 1); | |
200 | bb2 = e2->dest; | |
0385f644 | 201 | |
80c4ed35 AP |
202 | /* We cannot do the optimization on abnormal edges. */ |
203 | if ((e1->flags & EDGE_ABNORMAL) != 0 | |
204 | || (e2->flags & EDGE_ABNORMAL) != 0) | |
205 | continue; | |
0385f644 | 206 | |
80c4ed35 | 207 | /* If either bb1's succ or bb2 or bb2's succ is non NULL. */ |
c5cbcccf | 208 | if (EDGE_COUNT (bb1->succs) == 0 |
80c4ed35 | 209 | || bb2 == NULL |
c5cbcccf | 210 | || EDGE_COUNT (bb2->succs) == 0) |
80c4ed35 | 211 | continue; |
0385f644 | 212 | |
80c4ed35 AP |
213 | /* Find the bb which is the fall through to the other. */ |
214 | if (EDGE_SUCC (bb1, 0)->dest == bb2) | |
215 | ; | |
216 | else if (EDGE_SUCC (bb2, 0)->dest == bb1) | |
217 | { | |
6b4db501 MM |
218 | std::swap (bb1, bb2); |
219 | std::swap (e1, e2); | |
80c4ed35 | 220 | } |
23782cc3 JJ |
221 | else if (do_store_elim |
222 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) | |
223 | { | |
224 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
225 | ||
226 | if (!single_succ_p (bb1) | |
227 | || (EDGE_SUCC (bb1, 0)->flags & EDGE_FALLTHRU) == 0 | |
228 | || !single_succ_p (bb2) | |
229 | || (EDGE_SUCC (bb2, 0)->flags & EDGE_FALLTHRU) == 0 | |
230 | || EDGE_COUNT (bb3->preds) != 2) | |
231 | continue; | |
232 | if (cond_if_else_store_replacement (bb1, bb2, bb3)) | |
233 | cfgchanged = true; | |
234 | continue; | |
235 | } | |
372a6eb8 | 236 | else if (do_hoist_loads |
cfd719e7 | 237 | && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest) |
372a6eb8 BS |
238 | { |
239 | basic_block bb3 = EDGE_SUCC (bb1, 0)->dest; | |
240 | ||
241 | if (!FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (cond_stmt))) | |
242 | && single_succ_p (bb1) | |
243 | && single_succ_p (bb2) | |
244 | && single_pred_p (bb1) | |
245 | && single_pred_p (bb2) | |
246 | && EDGE_COUNT (bb->succs) == 2 | |
247 | && EDGE_COUNT (bb3->preds) == 2 | |
248 | /* If one edge or the other is dominant, a conditional move | |
249 | is likely to perform worse than the well-predicted branch. */ | |
250 | && !predictable_edge_p (EDGE_SUCC (bb, 0)) | |
251 | && !predictable_edge_p (EDGE_SUCC (bb, 1))) | |
252 | hoist_adjacent_loads (bb, bb1, bb2, bb3); | |
253 | continue; | |
254 | } | |
80c4ed35 | 255 | else |
c9ef86a1 | 256 | continue; |
0385f644 | 257 | |
80c4ed35 | 258 | e1 = EDGE_SUCC (bb1, 0); |
0385f644 | 259 | |
80c4ed35 | 260 | /* Make sure that bb1 is just a fall through. */ |
3d040dbc | 261 | if (!single_succ_p (bb1) |
80c4ed35 AP |
262 | || (e1->flags & EDGE_FALLTHRU) == 0) |
263 | continue; | |
0385f644 | 264 | |
2a925431 KH |
265 | /* Also make sure that bb1 only have one predecessor and that it |
266 | is bb. */ | |
c5cbcccf ZD |
267 | if (!single_pred_p (bb1) |
268 | || single_pred (bb1) != bb) | |
80c4ed35 | 269 | continue; |
0385f644 | 270 | |
a5828d1e MM |
271 | if (do_store_elim) |
272 | { | |
273 | /* bb1 is the middle block, bb2 the join block, bb the split block, | |
274 | e1 the fallthrough edge from bb1 to bb2. We can't do the | |
275 | optimization if the join block has more than two predecessors. */ | |
276 | if (EDGE_COUNT (bb2->preds) > 2) | |
277 | continue; | |
278 | if (cond_store_replacement (bb1, bb2, e1, e2, nontrap)) | |
279 | cfgchanged = true; | |
280 | } | |
281 | else | |
282 | { | |
726a989a | 283 | gimple_seq phis = phi_nodes (bb2); |
e106efc7 | 284 | gimple_stmt_iterator gsi; |
210ac0b7 | 285 | bool candorest = true; |
b928d32b | 286 | |
210ac0b7 AP |
287 | /* Value replacement can work with more than one PHI |
288 | so try that first. */ | |
289 | for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi)) | |
290 | { | |
538dd0b7 | 291 | phi = as_a <gphi *> (gsi_stmt (gsi)); |
210ac0b7 AP |
292 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); |
293 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
294 | if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1) == 2) | |
295 | { | |
296 | candorest = false; | |
297 | cfgchanged = true; | |
298 | break; | |
299 | } | |
300 | } | |
a5828d1e | 301 | |
210ac0b7 AP |
302 | if (!candorest) |
303 | continue; | |
c9ef86a1 | 304 | |
b928d32b | 305 | phi = single_non_singleton_phi_for_edges (phis, e1, e2); |
e106efc7 | 306 | if (!phi) |
a5828d1e MM |
307 | continue; |
308 | ||
726a989a RB |
309 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); |
310 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
a5828d1e MM |
311 | |
312 | /* Something is wrong if we cannot find the arguments in the PHI | |
313 | node. */ | |
0e0997a2 | 314 | gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE); |
a5828d1e | 315 | |
0e0997a2 | 316 | gphi *newphi = factor_out_conditional_conversion (e1, e2, phi, |
cfd719e7 JJ |
317 | arg0, arg1, |
318 | cond_stmt); | |
0e0997a2 | 319 | if (newphi != NULL) |
98441735 | 320 | { |
0e0997a2 | 321 | phi = newphi; |
98441735 KV |
322 | /* factor_out_conditional_conversion may create a new PHI in |
323 | BB2 and eliminate an existing PHI in BB2. Recompute values | |
324 | that may be affected by that change. */ | |
98441735 KV |
325 | arg0 = gimple_phi_arg_def (phi, e1->dest_idx); |
326 | arg1 = gimple_phi_arg_def (phi, e2->dest_idx); | |
0e0997a2 | 327 | gcc_assert (arg0 != NULL_TREE && arg1 != NULL_TREE); |
98441735 KV |
328 | } |
329 | ||
a5828d1e MM |
330 | /* Do the replacement of conditional if it can be done. */ |
331 | if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
332 | cfgchanged = true; | |
a5828d1e MM |
333 | else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) |
334 | cfgchanged = true; | |
335 | else if (minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1)) | |
336 | cfgchanged = true; | |
337 | } | |
8eaa0f34 ZD |
338 | } |
339 | ||
340 | free (bb_order); | |
b8698a0f | 341 | |
a5828d1e | 342 | if (do_store_elim) |
6e2830c3 | 343 | delete nontrap; |
a5828d1e MM |
344 | /* If the CFG has changed, we should cleanup the CFG. */ |
345 | if (cfgchanged && do_store_elim) | |
346 | { | |
347 | /* In cond-store replacement we have added some loads on edges | |
348 | and new VOPS (as we moved the store, and created a load). */ | |
726a989a | 349 | gsi_commit_edge_inserts (); |
a5828d1e MM |
350 | return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals; |
351 | } | |
352 | else if (cfgchanged) | |
353 | return TODO_cleanup_cfg; | |
354 | return 0; | |
8eaa0f34 ZD |
355 | } |
356 | ||
696e78bf | 357 | /* Replace PHI node element whose edge is E in block BB with variable NEW. |
80c4ed35 | 358 | Remove the edge from COND_BLOCK which does not lead to BB (COND_BLOCK |
1833df5c JL |
359 | is known to have two edges, one of which must reach BB). */ |
360 | ||
361 | static void | |
e5206274 | 362 | replace_phi_edge_with_variable (basic_block cond_block, |
355fe088 | 363 | edge e, gimple *phi, tree new_tree) |
1833df5c | 364 | { |
726a989a | 365 | basic_block bb = gimple_bb (phi); |
8a807136 | 366 | basic_block block_to_remove; |
726a989a | 367 | gimple_stmt_iterator gsi; |
80c4ed35 | 368 | |
0385f644 | 369 | /* Change the PHI argument to new. */ |
c22940cd | 370 | SET_USE (PHI_ARG_DEF_PTR (phi, e->dest_idx), new_tree); |
8a807136 | 371 | |
8a807136 | 372 | /* Remove the empty basic block. */ |
628f6a4e | 373 | if (EDGE_SUCC (cond_block, 0)->dest == bb) |
1833df5c | 374 | { |
628f6a4e BE |
375 | EDGE_SUCC (cond_block, 0)->flags |= EDGE_FALLTHRU; |
376 | EDGE_SUCC (cond_block, 0)->flags &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); | |
357067f2 | 377 | EDGE_SUCC (cond_block, 0)->probability = profile_probability::always (); |
8a807136 | 378 | |
628f6a4e | 379 | block_to_remove = EDGE_SUCC (cond_block, 1)->dest; |
1833df5c JL |
380 | } |
381 | else | |
382 | { | |
628f6a4e BE |
383 | EDGE_SUCC (cond_block, 1)->flags |= EDGE_FALLTHRU; |
384 | EDGE_SUCC (cond_block, 1)->flags | |
1833df5c | 385 | &= ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); |
357067f2 | 386 | EDGE_SUCC (cond_block, 1)->probability = profile_probability::always (); |
8a807136 | 387 | |
628f6a4e | 388 | block_to_remove = EDGE_SUCC (cond_block, 0)->dest; |
1833df5c | 389 | } |
8a807136 | 390 | delete_basic_block (block_to_remove); |
0385f644 | 391 | |
1833df5c | 392 | /* Eliminate the COND_EXPR at the end of COND_BLOCK. */ |
726a989a RB |
393 | gsi = gsi_last_bb (cond_block); |
394 | gsi_remove (&gsi, true); | |
0385f644 | 395 | |
1833df5c JL |
396 | if (dump_file && (dump_flags & TDF_DETAILS)) |
397 | fprintf (dump_file, | |
398 | "COND_EXPR in block %d and PHI in block %d converted to straightline code.\n", | |
399 | cond_block->index, | |
400 | bb->index); | |
401 | } | |
402 | ||
98441735 KV |
403 | /* PR66726: Factor conversion out of COND_EXPR. If the arguments of the PHI |
404 | stmt are CONVERT_STMT, factor out the conversion and perform the conversion | |
cfd719e7 JJ |
405 | to the result of PHI stmt. COND_STMT is the controlling predicate. |
406 | Return the newly-created PHI, if any. */ | |
98441735 | 407 | |
0e0997a2 | 408 | static gphi * |
98441735 | 409 | factor_out_conditional_conversion (edge e0, edge e1, gphi *phi, |
cfd719e7 | 410 | tree arg0, tree arg1, gimple *cond_stmt) |
98441735 | 411 | { |
355fe088 | 412 | gimple *arg0_def_stmt = NULL, *arg1_def_stmt = NULL, *new_stmt; |
98441735 KV |
413 | tree new_arg0 = NULL_TREE, new_arg1 = NULL_TREE; |
414 | tree temp, result; | |
415 | gphi *newphi; | |
416 | gimple_stmt_iterator gsi, gsi_for_def; | |
417 | source_location locus = gimple_location (phi); | |
418 | enum tree_code convert_code; | |
419 | ||
420 | /* Handle only PHI statements with two arguments. TODO: If all | |
421 | other arguments to PHI are INTEGER_CST or if their defining | |
422 | statement have the same unary operation, we can handle more | |
423 | than two arguments too. */ | |
424 | if (gimple_phi_num_args (phi) != 2) | |
0e0997a2 | 425 | return NULL; |
98441735 KV |
426 | |
427 | /* First canonicalize to simplify tests. */ | |
428 | if (TREE_CODE (arg0) != SSA_NAME) | |
429 | { | |
430 | std::swap (arg0, arg1); | |
431 | std::swap (e0, e1); | |
432 | } | |
433 | ||
434 | if (TREE_CODE (arg0) != SSA_NAME | |
435 | || (TREE_CODE (arg1) != SSA_NAME | |
436 | && TREE_CODE (arg1) != INTEGER_CST)) | |
0e0997a2 | 437 | return NULL; |
98441735 KV |
438 | |
439 | /* Check if arg0 is an SSA_NAME and the stmt which defines arg0 is | |
440 | a conversion. */ | |
441 | arg0_def_stmt = SSA_NAME_DEF_STMT (arg0); | |
a88a7b22 | 442 | if (!gimple_assign_cast_p (arg0_def_stmt)) |
0e0997a2 | 443 | return NULL; |
98441735 KV |
444 | |
445 | /* Use the RHS as new_arg0. */ | |
446 | convert_code = gimple_assign_rhs_code (arg0_def_stmt); | |
447 | new_arg0 = gimple_assign_rhs1 (arg0_def_stmt); | |
448 | if (convert_code == VIEW_CONVERT_EXPR) | |
a88a7b22 EB |
449 | { |
450 | new_arg0 = TREE_OPERAND (new_arg0, 0); | |
451 | if (!is_gimple_reg_type (TREE_TYPE (new_arg0))) | |
452 | return NULL; | |
453 | } | |
98441735 KV |
454 | |
455 | if (TREE_CODE (arg1) == SSA_NAME) | |
456 | { | |
457 | /* Check if arg1 is an SSA_NAME and the stmt which defines arg1 | |
458 | is a conversion. */ | |
459 | arg1_def_stmt = SSA_NAME_DEF_STMT (arg1); | |
460 | if (!is_gimple_assign (arg1_def_stmt) | |
461 | || gimple_assign_rhs_code (arg1_def_stmt) != convert_code) | |
0e0997a2 | 462 | return NULL; |
98441735 KV |
463 | |
464 | /* Use the RHS as new_arg1. */ | |
465 | new_arg1 = gimple_assign_rhs1 (arg1_def_stmt); | |
466 | if (convert_code == VIEW_CONVERT_EXPR) | |
467 | new_arg1 = TREE_OPERAND (new_arg1, 0); | |
468 | } | |
469 | else | |
470 | { | |
471 | /* If arg1 is an INTEGER_CST, fold it to new type. */ | |
472 | if (INTEGRAL_TYPE_P (TREE_TYPE (new_arg0)) | |
473 | && int_fits_type_p (arg1, TREE_TYPE (new_arg0))) | |
474 | { | |
475 | if (gimple_assign_cast_p (arg0_def_stmt)) | |
cfd719e7 JJ |
476 | { |
477 | /* For the INTEGER_CST case, we are just moving the | |
478 | conversion from one place to another, which can often | |
479 | hurt as the conversion moves further away from the | |
480 | statement that computes the value. So, perform this | |
481 | only if new_arg0 is an operand of COND_STMT, or | |
482 | if arg0_def_stmt is the only non-debug stmt in | |
483 | its basic block, because then it is possible this | |
484 | could enable further optimizations (minmax replacement | |
485 | etc.). See PR71016. */ | |
486 | if (new_arg0 != gimple_cond_lhs (cond_stmt) | |
487 | && new_arg0 != gimple_cond_rhs (cond_stmt) | |
488 | && gimple_bb (arg0_def_stmt) == e0->src) | |
489 | { | |
490 | gsi = gsi_for_stmt (arg0_def_stmt); | |
491 | gsi_prev_nondebug (&gsi); | |
492 | if (!gsi_end_p (gsi)) | |
493 | return NULL; | |
494 | gsi = gsi_for_stmt (arg0_def_stmt); | |
495 | gsi_next_nondebug (&gsi); | |
496 | if (!gsi_end_p (gsi)) | |
497 | return NULL; | |
498 | } | |
499 | new_arg1 = fold_convert (TREE_TYPE (new_arg0), arg1); | |
500 | } | |
98441735 | 501 | else |
0e0997a2 | 502 | return NULL; |
98441735 KV |
503 | } |
504 | else | |
0e0997a2 | 505 | return NULL; |
98441735 KV |
506 | } |
507 | ||
508 | /* If arg0/arg1 have > 1 use, then this transformation actually increases | |
509 | the number of expressions evaluated at runtime. */ | |
510 | if (!has_single_use (arg0) | |
511 | || (arg1_def_stmt && !has_single_use (arg1))) | |
0e0997a2 | 512 | return NULL; |
98441735 KV |
513 | |
514 | /* If types of new_arg0 and new_arg1 are different bailout. */ | |
515 | if (!types_compatible_p (TREE_TYPE (new_arg0), TREE_TYPE (new_arg1))) | |
0e0997a2 | 516 | return NULL; |
98441735 KV |
517 | |
518 | /* Create a new PHI stmt. */ | |
519 | result = PHI_RESULT (phi); | |
520 | temp = make_ssa_name (TREE_TYPE (new_arg0), NULL); | |
521 | newphi = create_phi_node (temp, gimple_bb (phi)); | |
522 | ||
523 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
524 | { | |
525 | fprintf (dump_file, "PHI "); | |
ef6cb4c7 | 526 | print_generic_expr (dump_file, gimple_phi_result (phi)); |
98441735 KV |
527 | fprintf (dump_file, |
528 | " changed to factor conversion out from COND_EXPR.\n"); | |
529 | fprintf (dump_file, "New stmt with CAST that defines "); | |
ef6cb4c7 | 530 | print_generic_expr (dump_file, result); |
98441735 KV |
531 | fprintf (dump_file, ".\n"); |
532 | } | |
533 | ||
534 | /* Remove the old cast(s) that has single use. */ | |
535 | gsi_for_def = gsi_for_stmt (arg0_def_stmt); | |
536 | gsi_remove (&gsi_for_def, true); | |
d1acc3f4 JL |
537 | release_defs (arg0_def_stmt); |
538 | ||
98441735 KV |
539 | if (arg1_def_stmt) |
540 | { | |
541 | gsi_for_def = gsi_for_stmt (arg1_def_stmt); | |
542 | gsi_remove (&gsi_for_def, true); | |
d1acc3f4 | 543 | release_defs (arg1_def_stmt); |
98441735 KV |
544 | } |
545 | ||
546 | add_phi_arg (newphi, new_arg0, e0, locus); | |
547 | add_phi_arg (newphi, new_arg1, e1, locus); | |
548 | ||
549 | /* Create the conversion stmt and insert it. */ | |
550 | if (convert_code == VIEW_CONVERT_EXPR) | |
551 | temp = fold_build1 (VIEW_CONVERT_EXPR, TREE_TYPE (result), temp); | |
cfd719e7 | 552 | new_stmt = gimple_build_assign (result, convert_code, temp); |
98441735 KV |
553 | gsi = gsi_after_labels (gimple_bb (phi)); |
554 | gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); | |
555 | ||
d1acc3f4 | 556 | /* Remove the original PHI stmt. */ |
98441735 KV |
557 | gsi = gsi_for_stmt (phi); |
558 | gsi_remove (&gsi, true); | |
0e0997a2 | 559 | return newphi; |
98441735 KV |
560 | } |
561 | ||
1833df5c JL |
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 | |
471854f8 | 566 | is argument 0 from PHI. Likewise for ARG1. */ |
1833df5c JL |
567 | |
568 | static bool | |
80c4ed35 | 569 | conditional_replacement (basic_block cond_bb, basic_block middle_bb, |
538dd0b7 | 570 | edge e0, edge e1, gphi *phi, |
80c4ed35 | 571 | tree arg0, tree arg1) |
1833df5c JL |
572 | { |
573 | tree result; | |
355fe088 | 574 | gimple *stmt; |
538dd0b7 | 575 | gassign *new_stmt; |
726a989a RB |
576 | tree cond; |
577 | gimple_stmt_iterator gsi; | |
1833df5c | 578 | edge true_edge, false_edge; |
726a989a | 579 | tree new_var, new_var2; |
809c929c | 580 | bool neg; |
1833df5c | 581 | |
550386ad | 582 | /* FIXME: Gimplification of complex type is too hard for now. */ |
5dcf6b7f JJ |
583 | /* We aren't prepared to handle vectors either (and it is a question |
584 | if it would be worthwhile anyway). */ | |
585 | if (!(INTEGRAL_TYPE_P (TREE_TYPE (arg0)) | |
586 | || POINTER_TYPE_P (TREE_TYPE (arg0))) | |
587 | || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
588 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) | |
550386ad AP |
589 | return false; |
590 | ||
809c929c PB |
591 | /* The PHI arguments have the constants 0 and 1, or 0 and -1, then |
592 | convert it to the conditional. */ | |
1833df5c JL |
593 | if ((integer_zerop (arg0) && integer_onep (arg1)) |
594 | || (integer_zerop (arg1) && integer_onep (arg0))) | |
809c929c PB |
595 | neg = false; |
596 | else if ((integer_zerop (arg0) && integer_all_onesp (arg1)) | |
597 | || (integer_zerop (arg1) && integer_all_onesp (arg0))) | |
598 | neg = true; | |
1833df5c JL |
599 | else |
600 | return false; | |
0385f644 | 601 | |
80c4ed35 | 602 | if (!empty_block_p (middle_bb)) |
1833df5c | 603 | return false; |
0385f644 | 604 | |
726a989a | 605 | /* At this point we know we have a GIMPLE_COND with two successors. |
14886ab7 JL |
606 | One successor is BB, the other successor is an empty block which |
607 | falls through into BB. | |
0385f644 | 608 | |
14886ab7 | 609 | There is a single PHI node at the join point (BB) and its arguments |
809c929c | 610 | are constants (0, 1) or (0, -1). |
0385f644 | 611 | |
14886ab7 | 612 | So, given the condition COND, and the two PHI arguments, we can |
0385f644 KH |
613 | rewrite this PHI into non-branching code: |
614 | ||
14886ab7 | 615 | dest = (COND) or dest = COND' |
0385f644 | 616 | |
14886ab7 JL |
617 | We use the condition as-is if the argument associated with the |
618 | true edge has the value one or the argument associated with the | |
619 | false edge as the value zero. Note that those conditions are not | |
726a989a | 620 | the same since only one of the outgoing edges from the GIMPLE_COND |
14886ab7 | 621 | will directly reach BB and thus be associated with an argument. */ |
571325db | 622 | |
726a989a RB |
623 | stmt = last_stmt (cond_bb); |
624 | result = PHI_RESULT (phi); | |
800dd123 | 625 | |
726a989a RB |
626 | /* To handle special cases like floating point comparison, it is easier and |
627 | less error-prone to build a tree and gimplify it on the fly though it is | |
628 | less efficient. */ | |
f8ecf734 RG |
629 | cond = fold_build2_loc (gimple_location (stmt), |
630 | gimple_cond_code (stmt), boolean_type_node, | |
631 | gimple_cond_lhs (stmt), gimple_cond_rhs (stmt)); | |
6de9cd9a | 632 | |
726a989a RB |
633 | /* We need to know which is the true edge and which is the false |
634 | edge so that we know when to invert the condition below. */ | |
635 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
636 | if ((e0 == true_edge && integer_zerop (arg0)) | |
809c929c | 637 | || (e0 == false_edge && !integer_zerop (arg0)) |
726a989a | 638 | || (e1 == true_edge && integer_zerop (arg1)) |
809c929c | 639 | || (e1 == false_edge && !integer_zerop (arg1))) |
f8ecf734 | 640 | cond = fold_build1_loc (gimple_location (stmt), |
809c929c PB |
641 | TRUTH_NOT_EXPR, TREE_TYPE (cond), cond); |
642 | ||
643 | if (neg) | |
644 | { | |
645 | cond = fold_convert_loc (gimple_location (stmt), | |
646 | TREE_TYPE (result), cond); | |
647 | cond = fold_build1_loc (gimple_location (stmt), | |
648 | NEGATE_EXPR, TREE_TYPE (cond), cond); | |
649 | } | |
726a989a RB |
650 | |
651 | /* Insert our new statements at the end of conditional block before the | |
652 | COND_STMT. */ | |
653 | gsi = gsi_for_stmt (stmt); | |
654 | new_var = force_gimple_operand_gsi (&gsi, cond, true, NULL, true, | |
655 | GSI_SAME_STMT); | |
656 | ||
657 | if (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (new_var))) | |
658 | { | |
f5045c96 AM |
659 | source_location locus_0, locus_1; |
660 | ||
b731b390 | 661 | new_var2 = make_ssa_name (TREE_TYPE (result)); |
0d0e4a03 | 662 | new_stmt = gimple_build_assign (new_var2, CONVERT_EXPR, new_var); |
726a989a RB |
663 | gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT); |
664 | new_var = new_var2; | |
f5045c96 AM |
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); | |
6de9cd9a | 672 | } |
0385f644 | 673 | |
726a989a | 674 | replace_phi_edge_with_variable (cond_bb, e1, phi, new_var); |
1833df5c | 675 | |
6de9cd9a DN |
676 | /* Note that we optimized this PHI. */ |
677 | return true; | |
678 | } | |
679 | ||
98dd3b73 RG |
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 | |
355fe088 | 685 | jump_function_from_stmt (tree *arg, gimple *stmt) |
98dd3b73 RG |
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); | |
a90c8804 | 692 | poly_int64 offset; |
98dd3b73 RG |
693 | tree tem = get_addr_base_and_unit_offset (TREE_OPERAND (rhs1, 0), |
694 | &offset); | |
695 | if (tem | |
696 | && TREE_CODE (tem) == MEM_REF | |
a90c8804 | 697 | && known_eq (mem_ref_offset (tem) + offset, 0)) |
98dd3b73 RG |
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 | ||
c9ef86a1 ZC |
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 | { | |
355fe088 | 726 | gimple *def1 = SSA_NAME_DEF_STMT (rhs); |
c9ef86a1 ZC |
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, | |
355fe088 | 758 | enum tree_code *code, gimple *cond) |
c9ef86a1 | 759 | { |
355fe088 | 760 | gimple *def; |
c9ef86a1 ZC |
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 | ||
421bf780 MG |
797 | /* Returns true if ARG is a neutral element for operation CODE |
798 | on the RIGHT side. */ | |
799 | ||
800 | static bool | |
801 | neutral_element_p (tree_code code, tree arg, bool right) | |
802 | { | |
803 | switch (code) | |
804 | { | |
805 | case PLUS_EXPR: | |
806 | case BIT_IOR_EXPR: | |
807 | case BIT_XOR_EXPR: | |
808 | return integer_zerop (arg); | |
809 | ||
810 | case LROTATE_EXPR: | |
811 | case RROTATE_EXPR: | |
812 | case LSHIFT_EXPR: | |
813 | case RSHIFT_EXPR: | |
814 | case MINUS_EXPR: | |
815 | case POINTER_PLUS_EXPR: | |
816 | return right && integer_zerop (arg); | |
817 | ||
818 | case MULT_EXPR: | |
819 | return integer_onep (arg); | |
820 | ||
821 | case TRUNC_DIV_EXPR: | |
822 | case CEIL_DIV_EXPR: | |
823 | case FLOOR_DIV_EXPR: | |
824 | case ROUND_DIV_EXPR: | |
825 | case EXACT_DIV_EXPR: | |
826 | return right && integer_onep (arg); | |
827 | ||
828 | case BIT_AND_EXPR: | |
829 | return integer_all_onesp (arg); | |
830 | ||
831 | default: | |
832 | return false; | |
833 | } | |
834 | } | |
835 | ||
836 | /* Returns true if ARG is an absorbing element for operation CODE. */ | |
837 | ||
838 | static bool | |
9513d5fb | 839 | absorbing_element_p (tree_code code, tree arg, bool right, tree rval) |
421bf780 MG |
840 | { |
841 | switch (code) | |
842 | { | |
843 | case BIT_IOR_EXPR: | |
844 | return integer_all_onesp (arg); | |
845 | ||
846 | case MULT_EXPR: | |
847 | case BIT_AND_EXPR: | |
848 | return integer_zerop (arg); | |
849 | ||
9737f35b RB |
850 | case LSHIFT_EXPR: |
851 | case RSHIFT_EXPR: | |
852 | case LROTATE_EXPR: | |
853 | case RROTATE_EXPR: | |
9513d5fb RB |
854 | return !right && integer_zerop (arg); |
855 | ||
9737f35b RB |
856 | case TRUNC_DIV_EXPR: |
857 | case CEIL_DIV_EXPR: | |
858 | case FLOOR_DIV_EXPR: | |
859 | case ROUND_DIV_EXPR: | |
860 | case EXACT_DIV_EXPR: | |
861 | case TRUNC_MOD_EXPR: | |
862 | case CEIL_MOD_EXPR: | |
863 | case FLOOR_MOD_EXPR: | |
864 | case ROUND_MOD_EXPR: | |
9513d5fb RB |
865 | return (!right |
866 | && integer_zerop (arg) | |
867 | && tree_single_nonzero_warnv_p (rval, NULL)); | |
9737f35b | 868 | |
421bf780 MG |
869 | default: |
870 | return false; | |
871 | } | |
872 | } | |
873 | ||
3a3f4da9 | 874 | /* The function value_replacement does the main work of doing the value |
210ac0b7 AP |
875 | replacement. Return non-zero if the replacement is done. Otherwise return |
876 | 0. If we remove the middle basic block, return 2. | |
3a3f4da9 | 877 | BB is the basic block where the replacement is going to be done on. ARG0 |
471854f8 | 878 | is argument 0 from the PHI. Likewise for ARG1. */ |
3a3f4da9 | 879 | |
210ac0b7 | 880 | static int |
80c4ed35 | 881 | value_replacement (basic_block cond_bb, basic_block middle_bb, |
355fe088 | 882 | edge e0, edge e1, gimple *phi, |
80c4ed35 | 883 | tree arg0, tree arg1) |
3a3f4da9 | 884 | { |
98dd3b73 | 885 | gimple_stmt_iterator gsi; |
355fe088 | 886 | gimple *cond; |
3a3f4da9 | 887 | edge true_edge, false_edge; |
726a989a | 888 | enum tree_code code; |
210ac0b7 | 889 | bool emtpy_or_with_defined_p = true; |
3a3f4da9 AP |
890 | |
891 | /* If the type says honor signed zeros we cannot do this | |
471854f8 | 892 | optimization. */ |
3d3dbadd | 893 | if (HONOR_SIGNED_ZEROS (arg1)) |
210ac0b7 | 894 | return 0; |
3a3f4da9 | 895 | |
210ac0b7 AP |
896 | /* If there is a statement in MIDDLE_BB that defines one of the PHI |
897 | arguments, then adjust arg0 or arg1. */ | |
421bf780 | 898 | gsi = gsi_start_nondebug_after_labels_bb (middle_bb); |
210ac0b7 | 899 | while (!gsi_end_p (gsi)) |
98dd3b73 | 900 | { |
355fe088 | 901 | gimple *stmt = gsi_stmt (gsi); |
210ac0b7 AP |
902 | tree lhs; |
903 | gsi_next_nondebug (&gsi); | |
904 | if (!is_gimple_assign (stmt)) | |
98dd3b73 | 905 | { |
210ac0b7 AP |
906 | emtpy_or_with_defined_p = false; |
907 | continue; | |
98dd3b73 | 908 | } |
210ac0b7 AP |
909 | /* Now try to adjust arg0 or arg1 according to the computation |
910 | in the statement. */ | |
911 | lhs = gimple_assign_lhs (stmt); | |
912 | if (!(lhs == arg0 | |
913 | && jump_function_from_stmt (&arg0, stmt)) | |
914 | || (lhs == arg1 | |
915 | && jump_function_from_stmt (&arg1, stmt))) | |
916 | emtpy_or_with_defined_p = false; | |
98dd3b73 | 917 | } |
3a3f4da9 | 918 | |
726a989a RB |
919 | cond = last_stmt (cond_bb); |
920 | code = gimple_cond_code (cond); | |
3a3f4da9 AP |
921 | |
922 | /* This transformation is only valid for equality comparisons. */ | |
726a989a | 923 | if (code != NE_EXPR && code != EQ_EXPR) |
210ac0b7 | 924 | return 0; |
3a3f4da9 AP |
925 | |
926 | /* We need to know which is the true edge and which is the false | |
927 | edge so that we know if have abs or negative abs. */ | |
80c4ed35 | 928 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
3a3f4da9 AP |
929 | |
930 | /* At this point we know we have a COND_EXPR with two successors. | |
931 | One successor is BB, the other successor is an empty block which | |
932 | falls through into BB. | |
933 | ||
934 | The condition for the COND_EXPR is known to be NE_EXPR or EQ_EXPR. | |
935 | ||
936 | There is a single PHI node at the join point (BB) with two arguments. | |
937 | ||
938 | We now need to verify that the two arguments in the PHI node match | |
939 | the two arguments to the equality comparison. */ | |
0385f644 | 940 | |
c9ef86a1 | 941 | if (operand_equal_for_value_replacement (arg0, arg1, &code, cond)) |
3a3f4da9 AP |
942 | { |
943 | edge e; | |
944 | tree arg; | |
945 | ||
84c672b9 JL |
946 | /* For NE_EXPR, we want to build an assignment result = arg where |
947 | arg is the PHI argument associated with the true edge. For | |
948 | EQ_EXPR we want the PHI argument associated with the false edge. */ | |
726a989a | 949 | e = (code == NE_EXPR ? true_edge : false_edge); |
84c672b9 JL |
950 | |
951 | /* Unfortunately, E may not reach BB (it may instead have gone to | |
952 | OTHER_BLOCK). If that is the case, then we want the single outgoing | |
953 | edge from OTHER_BLOCK which reaches BB and represents the desired | |
954 | path from COND_BLOCK. */ | |
80c4ed35 | 955 | if (e->dest == middle_bb) |
c5cbcccf | 956 | e = single_succ_edge (e->dest); |
84c672b9 JL |
957 | |
958 | /* Now we know the incoming edge to BB that has the argument for the | |
959 | RHS of our new assignment statement. */ | |
80c4ed35 | 960 | if (e0 == e) |
3a3f4da9 AP |
961 | arg = arg0; |
962 | else | |
963 | arg = arg1; | |
964 | ||
210ac0b7 | 965 | /* If the middle basic block was empty or is defining the |
b928d32b AP |
966 | PHI arguments and this is a single phi where the args are different |
967 | for the edges e0 and e1 then we can remove the middle basic block. */ | |
210ac0b7 | 968 | if (emtpy_or_with_defined_p |
b928d32b | 969 | && single_non_singleton_phi_for_edges (phi_nodes (gimple_bb (phi)), |
1a6230a8 | 970 | e0, e1) == phi) |
210ac0b7 AP |
971 | { |
972 | replace_phi_edge_with_variable (cond_bb, e1, phi, arg); | |
973 | /* Note that we optimized this PHI. */ | |
974 | return 2; | |
975 | } | |
976 | else | |
977 | { | |
978 | /* Replace the PHI arguments with arg. */ | |
979 | SET_PHI_ARG_DEF (phi, e0->dest_idx, arg); | |
980 | SET_PHI_ARG_DEF (phi, e1->dest_idx, arg); | |
981 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
982 | { | |
983 | fprintf (dump_file, "PHI "); | |
ef6cb4c7 | 984 | print_generic_expr (dump_file, gimple_phi_result (phi)); |
b928d32b AP |
985 | fprintf (dump_file, " reduced for COND_EXPR in block %d to ", |
986 | cond_bb->index); | |
ef6cb4c7 | 987 | print_generic_expr (dump_file, arg); |
210ac0b7 AP |
988 | fprintf (dump_file, ".\n"); |
989 | } | |
990 | return 1; | |
991 | } | |
3a3f4da9 | 992 | |
3a3f4da9 | 993 | } |
421bf780 | 994 | |
14745bca JJ |
995 | /* Now optimize (x != 0) ? x + y : y to just x + y. */ |
996 | gsi = gsi_last_nondebug_bb (middle_bb); | |
997 | if (gsi_end_p (gsi)) | |
998 | return 0; | |
999 | ||
1000 | gimple *assign = gsi_stmt (gsi); | |
1001 | if (!is_gimple_assign (assign) | |
421bf780 MG |
1002 | || gimple_assign_rhs_class (assign) != GIMPLE_BINARY_RHS |
1003 | || (!INTEGRAL_TYPE_P (TREE_TYPE (arg0)) | |
1004 | && !POINTER_TYPE_P (TREE_TYPE (arg0)))) | |
1005 | return 0; | |
1006 | ||
ca73a1f7 MG |
1007 | /* Punt if there are (degenerate) PHIs in middle_bb, there should not be. */ |
1008 | if (!gimple_seq_empty_p (phi_nodes (middle_bb))) | |
1009 | return 0; | |
1010 | ||
14745bca JJ |
1011 | /* Allow up to 2 cheap preparation statements that prepare argument |
1012 | for assign, e.g.: | |
1013 | if (y_4 != 0) | |
1014 | goto <bb 3>; | |
1015 | else | |
1016 | goto <bb 4>; | |
1017 | <bb 3>: | |
1018 | _1 = (int) y_4; | |
1019 | iftmp.0_6 = x_5(D) r<< _1; | |
1020 | <bb 4>: | |
1021 | # iftmp.0_2 = PHI <iftmp.0_6(3), x_5(D)(2)> | |
1022 | or: | |
1023 | if (y_3(D) == 0) | |
1024 | goto <bb 4>; | |
1025 | else | |
1026 | goto <bb 3>; | |
1027 | <bb 3>: | |
1028 | y_4 = y_3(D) & 31; | |
1029 | _1 = (int) y_4; | |
1030 | _6 = x_5(D) r<< _1; | |
1031 | <bb 4>: | |
1032 | # _2 = PHI <x_5(D)(2), _6(3)> */ | |
1033 | gimple *prep_stmt[2] = { NULL, NULL }; | |
1034 | int prep_cnt; | |
1035 | for (prep_cnt = 0; ; prep_cnt++) | |
1036 | { | |
1037 | gsi_prev_nondebug (&gsi); | |
1038 | if (gsi_end_p (gsi)) | |
1039 | break; | |
1040 | ||
1041 | gimple *g = gsi_stmt (gsi); | |
1042 | if (gimple_code (g) == GIMPLE_LABEL) | |
1043 | break; | |
1044 | ||
1045 | if (prep_cnt == 2 || !is_gimple_assign (g)) | |
1046 | return 0; | |
1047 | ||
1048 | tree lhs = gimple_assign_lhs (g); | |
1049 | tree rhs1 = gimple_assign_rhs1 (g); | |
1050 | use_operand_p use_p; | |
1051 | gimple *use_stmt; | |
1052 | if (TREE_CODE (lhs) != SSA_NAME | |
1053 | || TREE_CODE (rhs1) != SSA_NAME | |
1054 | || !INTEGRAL_TYPE_P (TREE_TYPE (lhs)) | |
1055 | || !INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
1056 | || !single_imm_use (lhs, &use_p, &use_stmt) | |
1057 | || use_stmt != (prep_cnt ? prep_stmt[prep_cnt - 1] : assign)) | |
1058 | return 0; | |
1059 | switch (gimple_assign_rhs_code (g)) | |
1060 | { | |
1061 | CASE_CONVERT: | |
1062 | break; | |
1063 | case PLUS_EXPR: | |
1064 | case BIT_AND_EXPR: | |
1065 | case BIT_IOR_EXPR: | |
1066 | case BIT_XOR_EXPR: | |
1067 | if (TREE_CODE (gimple_assign_rhs2 (g)) != INTEGER_CST) | |
1068 | return 0; | |
1069 | break; | |
1070 | default: | |
1071 | return 0; | |
1072 | } | |
1073 | prep_stmt[prep_cnt] = g; | |
1074 | } | |
1075 | ||
87a34442 MG |
1076 | /* Only transform if it removes the condition. */ |
1077 | if (!single_non_singleton_phi_for_edges (phi_nodes (gimple_bb (phi)), e0, e1)) | |
1078 | return 0; | |
1079 | ||
421bf780 MG |
1080 | /* Size-wise, this is always profitable. */ |
1081 | if (optimize_bb_for_speed_p (cond_bb) | |
1082 | /* The special case is useless if it has a low probability. */ | |
1083 | && profile_status_for_fn (cfun) != PROFILE_ABSENT | |
357067f2 | 1084 | && EDGE_PRED (middle_bb, 0)->probability < profile_probability::even () |
421bf780 | 1085 | /* If assign is cheap, there is no point avoiding it. */ |
14745bca | 1086 | && estimate_num_insns (bb_seq (middle_bb), &eni_time_weights) |
421bf780 MG |
1087 | >= 3 * estimate_num_insns (cond, &eni_time_weights)) |
1088 | return 0; | |
1089 | ||
1090 | tree lhs = gimple_assign_lhs (assign); | |
1091 | tree rhs1 = gimple_assign_rhs1 (assign); | |
1092 | tree rhs2 = gimple_assign_rhs2 (assign); | |
1093 | enum tree_code code_def = gimple_assign_rhs_code (assign); | |
1094 | tree cond_lhs = gimple_cond_lhs (cond); | |
1095 | tree cond_rhs = gimple_cond_rhs (cond); | |
1096 | ||
14745bca JJ |
1097 | /* Propagate the cond_rhs constant through preparation stmts, |
1098 | make sure UB isn't invoked while doing that. */ | |
1099 | for (int i = prep_cnt - 1; i >= 0; --i) | |
1100 | { | |
1101 | gimple *g = prep_stmt[i]; | |
1102 | tree grhs1 = gimple_assign_rhs1 (g); | |
1103 | if (!operand_equal_for_phi_arg_p (cond_lhs, grhs1)) | |
1104 | return 0; | |
1105 | cond_lhs = gimple_assign_lhs (g); | |
1106 | cond_rhs = fold_convert (TREE_TYPE (grhs1), cond_rhs); | |
1107 | if (TREE_CODE (cond_rhs) != INTEGER_CST | |
1108 | || TREE_OVERFLOW (cond_rhs)) | |
1109 | return 0; | |
1110 | if (gimple_assign_rhs_class (g) == GIMPLE_BINARY_RHS) | |
1111 | { | |
1112 | cond_rhs = int_const_binop (gimple_assign_rhs_code (g), cond_rhs, | |
1113 | gimple_assign_rhs2 (g)); | |
1114 | if (TREE_OVERFLOW (cond_rhs)) | |
1115 | return 0; | |
1116 | } | |
1117 | cond_rhs = fold_convert (TREE_TYPE (cond_lhs), cond_rhs); | |
1118 | if (TREE_CODE (cond_rhs) != INTEGER_CST | |
1119 | || TREE_OVERFLOW (cond_rhs)) | |
1120 | return 0; | |
1121 | } | |
1122 | ||
421bf780 MG |
1123 | if (((code == NE_EXPR && e1 == false_edge) |
1124 | || (code == EQ_EXPR && e1 == true_edge)) | |
1125 | && arg0 == lhs | |
1126 | && ((arg1 == rhs1 | |
1127 | && operand_equal_for_phi_arg_p (rhs2, cond_lhs) | |
1128 | && neutral_element_p (code_def, cond_rhs, true)) | |
1129 | || (arg1 == rhs2 | |
1130 | && operand_equal_for_phi_arg_p (rhs1, cond_lhs) | |
1131 | && neutral_element_p (code_def, cond_rhs, false)) | |
1132 | || (operand_equal_for_phi_arg_p (arg1, cond_rhs) | |
9737f35b | 1133 | && ((operand_equal_for_phi_arg_p (rhs2, cond_lhs) |
9513d5fb | 1134 | && absorbing_element_p (code_def, cond_rhs, true, rhs2)) |
9737f35b | 1135 | || (operand_equal_for_phi_arg_p (rhs1, cond_lhs) |
9513d5fb RB |
1136 | && absorbing_element_p (code_def, |
1137 | cond_rhs, false, rhs2)))))) | |
421bf780 MG |
1138 | { |
1139 | gsi = gsi_for_stmt (cond); | |
5a40ae3c RB |
1140 | /* Moving ASSIGN might change VR of lhs, e.g. when moving u_6 |
1141 | def-stmt in: | |
1142 | if (n_5 != 0) | |
1143 | goto <bb 3>; | |
1144 | else | |
1145 | goto <bb 4>; | |
1146 | ||
1147 | <bb 3>: | |
1148 | # RANGE [0, 4294967294] | |
1149 | u_6 = n_5 + 4294967295; | |
1150 | ||
1151 | <bb 4>: | |
1152 | # u_3 = PHI <u_6(3), 4294967295(2)> */ | |
1153 | reset_flow_sensitive_info (lhs); | |
f7a0790f JJ |
1154 | if (INTEGRAL_TYPE_P (TREE_TYPE (lhs))) |
1155 | { | |
f7a0790f JJ |
1156 | /* If available, we can use VR of phi result at least. */ |
1157 | tree phires = gimple_phi_result (phi); | |
1158 | struct range_info_def *phires_range_info | |
1159 | = SSA_NAME_RANGE_INFO (phires); | |
1160 | if (phires_range_info) | |
1161 | duplicate_ssa_name_range_info (lhs, SSA_NAME_RANGE_TYPE (phires), | |
1162 | phires_range_info); | |
1163 | } | |
14745bca JJ |
1164 | gimple_stmt_iterator gsi_from; |
1165 | for (int i = prep_cnt - 1; i >= 0; --i) | |
1166 | { | |
1167 | tree plhs = gimple_assign_lhs (prep_stmt[i]); | |
5a40ae3c | 1168 | reset_flow_sensitive_info (plhs); |
14745bca JJ |
1169 | gsi_from = gsi_for_stmt (prep_stmt[i]); |
1170 | gsi_move_before (&gsi_from, &gsi); | |
1171 | } | |
1172 | gsi_from = gsi_for_stmt (assign); | |
421bf780 MG |
1173 | gsi_move_before (&gsi_from, &gsi); |
1174 | replace_phi_edge_with_variable (cond_bb, e1, phi, lhs); | |
1175 | return 2; | |
1176 | } | |
1177 | ||
210ac0b7 | 1178 | return 0; |
3a3f4da9 AP |
1179 | } |
1180 | ||
8eaa0f34 ZD |
1181 | /* The function minmax_replacement does the main work of doing the minmax |
1182 | replacement. Return true if the replacement is done. Otherwise return | |
1183 | false. | |
1184 | BB is the basic block where the replacement is going to be done on. ARG0 | |
1185 | is argument 0 from the PHI. Likewise for ARG1. */ | |
1186 | ||
1187 | static bool | |
1188 | minmax_replacement (basic_block cond_bb, basic_block middle_bb, | |
355fe088 | 1189 | edge e0, edge e1, gimple *phi, |
8eaa0f34 ZD |
1190 | tree arg0, tree arg1) |
1191 | { | |
1192 | tree result, type; | |
538dd0b7 DM |
1193 | gcond *cond; |
1194 | gassign *new_stmt; | |
8eaa0f34 ZD |
1195 | edge true_edge, false_edge; |
1196 | enum tree_code cmp, minmax, ass_code; | |
a9fee7cd | 1197 | tree smaller, alt_smaller, larger, alt_larger, arg_true, arg_false; |
726a989a | 1198 | gimple_stmt_iterator gsi, gsi_from; |
8eaa0f34 ZD |
1199 | |
1200 | type = TREE_TYPE (PHI_RESULT (phi)); | |
1201 | ||
1202 | /* The optimization may be unsafe due to NaNs. */ | |
d657e995 | 1203 | if (HONOR_NANS (type) || HONOR_SIGNED_ZEROS (type)) |
8eaa0f34 ZD |
1204 | return false; |
1205 | ||
538dd0b7 | 1206 | cond = as_a <gcond *> (last_stmt (cond_bb)); |
726a989a | 1207 | cmp = gimple_cond_code (cond); |
8eaa0f34 ZD |
1208 | |
1209 | /* This transformation is only valid for order comparisons. Record which | |
1210 | operand is smaller/larger if the result of the comparison is true. */ | |
a9fee7cd RB |
1211 | alt_smaller = NULL_TREE; |
1212 | alt_larger = NULL_TREE; | |
8eaa0f34 ZD |
1213 | if (cmp == LT_EXPR || cmp == LE_EXPR) |
1214 | { | |
726a989a RB |
1215 | smaller = gimple_cond_lhs (cond); |
1216 | larger = gimple_cond_rhs (cond); | |
a9fee7cd RB |
1217 | /* If we have smaller < CST it is equivalent to smaller <= CST-1. |
1218 | Likewise smaller <= CST is equivalent to smaller < CST+1. */ | |
1219 | if (TREE_CODE (larger) == INTEGER_CST) | |
1220 | { | |
1221 | if (cmp == LT_EXPR) | |
1222 | { | |
1223 | bool overflow; | |
8e6cdc90 RS |
1224 | wide_int alt = wi::sub (wi::to_wide (larger), 1, |
1225 | TYPE_SIGN (TREE_TYPE (larger)), | |
a9fee7cd RB |
1226 | &overflow); |
1227 | if (! overflow) | |
1228 | alt_larger = wide_int_to_tree (TREE_TYPE (larger), alt); | |
1229 | } | |
1230 | else | |
1231 | { | |
1232 | bool overflow; | |
8e6cdc90 RS |
1233 | wide_int alt = wi::add (wi::to_wide (larger), 1, |
1234 | TYPE_SIGN (TREE_TYPE (larger)), | |
a9fee7cd RB |
1235 | &overflow); |
1236 | if (! overflow) | |
1237 | alt_larger = wide_int_to_tree (TREE_TYPE (larger), alt); | |
1238 | } | |
1239 | } | |
8eaa0f34 ZD |
1240 | } |
1241 | else if (cmp == GT_EXPR || cmp == GE_EXPR) | |
1242 | { | |
726a989a RB |
1243 | smaller = gimple_cond_rhs (cond); |
1244 | larger = gimple_cond_lhs (cond); | |
a9fee7cd RB |
1245 | /* If we have larger > CST it is equivalent to larger >= CST+1. |
1246 | Likewise larger >= CST is equivalent to larger > CST-1. */ | |
1247 | if (TREE_CODE (smaller) == INTEGER_CST) | |
1248 | { | |
1249 | if (cmp == GT_EXPR) | |
1250 | { | |
1251 | bool overflow; | |
8e6cdc90 RS |
1252 | wide_int alt = wi::add (wi::to_wide (smaller), 1, |
1253 | TYPE_SIGN (TREE_TYPE (smaller)), | |
a9fee7cd RB |
1254 | &overflow); |
1255 | if (! overflow) | |
1256 | alt_smaller = wide_int_to_tree (TREE_TYPE (smaller), alt); | |
1257 | } | |
1258 | else | |
1259 | { | |
1260 | bool overflow; | |
8e6cdc90 RS |
1261 | wide_int alt = wi::sub (wi::to_wide (smaller), 1, |
1262 | TYPE_SIGN (TREE_TYPE (smaller)), | |
a9fee7cd RB |
1263 | &overflow); |
1264 | if (! overflow) | |
1265 | alt_smaller = wide_int_to_tree (TREE_TYPE (smaller), alt); | |
1266 | } | |
1267 | } | |
8eaa0f34 ZD |
1268 | } |
1269 | else | |
1270 | return false; | |
1271 | ||
1272 | /* We need to know which is the true edge and which is the false | |
1273 | edge so that we know if have abs or negative abs. */ | |
1274 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); | |
1275 | ||
1276 | /* Forward the edges over the middle basic block. */ | |
1277 | if (true_edge->dest == middle_bb) | |
1278 | true_edge = EDGE_SUCC (true_edge->dest, 0); | |
1279 | if (false_edge->dest == middle_bb) | |
1280 | false_edge = EDGE_SUCC (false_edge->dest, 0); | |
1281 | ||
1282 | if (true_edge == e0) | |
1283 | { | |
1284 | gcc_assert (false_edge == e1); | |
1285 | arg_true = arg0; | |
1286 | arg_false = arg1; | |
1287 | } | |
1288 | else | |
1289 | { | |
1290 | gcc_assert (false_edge == e0); | |
1291 | gcc_assert (true_edge == e1); | |
1292 | arg_true = arg1; | |
1293 | arg_false = arg0; | |
1294 | } | |
1295 | ||
1296 | if (empty_block_p (middle_bb)) | |
1297 | { | |
a9fee7cd RB |
1298 | if ((operand_equal_for_phi_arg_p (arg_true, smaller) |
1299 | || (alt_smaller | |
1300 | && operand_equal_for_phi_arg_p (arg_true, alt_smaller))) | |
1301 | && (operand_equal_for_phi_arg_p (arg_false, larger) | |
1302 | || (alt_larger | |
1303 | && operand_equal_for_phi_arg_p (arg_true, alt_larger)))) | |
8eaa0f34 ZD |
1304 | { |
1305 | /* Case | |
b8698a0f | 1306 | |
8eaa0f34 ZD |
1307 | if (smaller < larger) |
1308 | rslt = smaller; | |
1309 | else | |
1310 | rslt = larger; */ | |
1311 | minmax = MIN_EXPR; | |
1312 | } | |
a9fee7cd RB |
1313 | else if ((operand_equal_for_phi_arg_p (arg_false, smaller) |
1314 | || (alt_smaller | |
1315 | && operand_equal_for_phi_arg_p (arg_false, alt_smaller))) | |
1316 | && (operand_equal_for_phi_arg_p (arg_true, larger) | |
1317 | || (alt_larger | |
1318 | && operand_equal_for_phi_arg_p (arg_true, alt_larger)))) | |
8eaa0f34 ZD |
1319 | minmax = MAX_EXPR; |
1320 | else | |
1321 | return false; | |
1322 | } | |
1323 | else | |
1324 | { | |
1325 | /* Recognize the following case, assuming d <= u: | |
1326 | ||
1327 | if (a <= u) | |
1328 | b = MAX (a, d); | |
1329 | x = PHI <b, u> | |
1330 | ||
1331 | This is equivalent to | |
1332 | ||
1333 | b = MAX (a, d); | |
1334 | x = MIN (b, u); */ | |
1335 | ||
355fe088 | 1336 | gimple *assign = last_and_only_stmt (middle_bb); |
726a989a | 1337 | tree lhs, op0, op1, bound; |
8eaa0f34 ZD |
1338 | |
1339 | if (!assign | |
726a989a | 1340 | || gimple_code (assign) != GIMPLE_ASSIGN) |
8eaa0f34 ZD |
1341 | return false; |
1342 | ||
726a989a RB |
1343 | lhs = gimple_assign_lhs (assign); |
1344 | ass_code = gimple_assign_rhs_code (assign); | |
8eaa0f34 ZD |
1345 | if (ass_code != MAX_EXPR && ass_code != MIN_EXPR) |
1346 | return false; | |
726a989a RB |
1347 | op0 = gimple_assign_rhs1 (assign); |
1348 | op1 = gimple_assign_rhs2 (assign); | |
8eaa0f34 ZD |
1349 | |
1350 | if (true_edge->src == middle_bb) | |
1351 | { | |
1352 | /* We got here if the condition is true, i.e., SMALLER < LARGER. */ | |
1353 | if (!operand_equal_for_phi_arg_p (lhs, arg_true)) | |
1354 | return false; | |
1355 | ||
a9fee7cd RB |
1356 | if (operand_equal_for_phi_arg_p (arg_false, larger) |
1357 | || (alt_larger | |
1358 | && operand_equal_for_phi_arg_p (arg_false, alt_larger))) | |
8eaa0f34 ZD |
1359 | { |
1360 | /* Case | |
1361 | ||
1362 | if (smaller < larger) | |
1363 | { | |
1364 | r' = MAX_EXPR (smaller, bound) | |
1365 | } | |
1366 | r = PHI <r', larger> --> to be turned to MIN_EXPR. */ | |
1367 | if (ass_code != MAX_EXPR) | |
1368 | return false; | |
1369 | ||
1370 | minmax = MIN_EXPR; | |
a9fee7cd RB |
1371 | if (operand_equal_for_phi_arg_p (op0, smaller) |
1372 | || (alt_smaller | |
1373 | && operand_equal_for_phi_arg_p (op0, alt_smaller))) | |
8eaa0f34 | 1374 | bound = op1; |
a9fee7cd RB |
1375 | else if (operand_equal_for_phi_arg_p (op1, smaller) |
1376 | || (alt_smaller | |
1377 | && operand_equal_for_phi_arg_p (op1, alt_smaller))) | |
8eaa0f34 ZD |
1378 | bound = op0; |
1379 | else | |
1380 | return false; | |
1381 | ||
1382 | /* We need BOUND <= LARGER. */ | |
987b67bc KH |
1383 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
1384 | bound, larger))) | |
8eaa0f34 ZD |
1385 | return false; |
1386 | } | |
a9fee7cd RB |
1387 | else if (operand_equal_for_phi_arg_p (arg_false, smaller) |
1388 | || (alt_smaller | |
1389 | && operand_equal_for_phi_arg_p (arg_false, alt_smaller))) | |
8eaa0f34 ZD |
1390 | { |
1391 | /* Case | |
1392 | ||
1393 | if (smaller < larger) | |
1394 | { | |
1395 | r' = MIN_EXPR (larger, bound) | |
1396 | } | |
1397 | r = PHI <r', smaller> --> to be turned to MAX_EXPR. */ | |
1398 | if (ass_code != MIN_EXPR) | |
1399 | return false; | |
1400 | ||
1401 | minmax = MAX_EXPR; | |
a9fee7cd RB |
1402 | if (operand_equal_for_phi_arg_p (op0, larger) |
1403 | || (alt_larger | |
1404 | && operand_equal_for_phi_arg_p (op0, alt_larger))) | |
8eaa0f34 | 1405 | bound = op1; |
a9fee7cd RB |
1406 | else if (operand_equal_for_phi_arg_p (op1, larger) |
1407 | || (alt_larger | |
1408 | && operand_equal_for_phi_arg_p (op1, alt_larger))) | |
8eaa0f34 ZD |
1409 | bound = op0; |
1410 | else | |
1411 | return false; | |
1412 | ||
1413 | /* We need BOUND >= SMALLER. */ | |
987b67bc KH |
1414 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1415 | bound, smaller))) | |
8eaa0f34 ZD |
1416 | return false; |
1417 | } | |
1418 | else | |
1419 | return false; | |
1420 | } | |
1421 | else | |
1422 | { | |
1423 | /* We got here if the condition is false, i.e., SMALLER > LARGER. */ | |
1424 | if (!operand_equal_for_phi_arg_p (lhs, arg_false)) | |
1425 | return false; | |
1426 | ||
a9fee7cd RB |
1427 | if (operand_equal_for_phi_arg_p (arg_true, larger) |
1428 | || (alt_larger | |
1429 | && operand_equal_for_phi_arg_p (arg_true, alt_larger))) | |
8eaa0f34 ZD |
1430 | { |
1431 | /* Case | |
1432 | ||
1433 | if (smaller > larger) | |
1434 | { | |
1435 | r' = MIN_EXPR (smaller, bound) | |
1436 | } | |
1437 | r = PHI <r', larger> --> to be turned to MAX_EXPR. */ | |
1438 | if (ass_code != MIN_EXPR) | |
1439 | return false; | |
1440 | ||
1441 | minmax = MAX_EXPR; | |
a9fee7cd RB |
1442 | if (operand_equal_for_phi_arg_p (op0, smaller) |
1443 | || (alt_smaller | |
1444 | && operand_equal_for_phi_arg_p (op0, alt_smaller))) | |
8eaa0f34 | 1445 | bound = op1; |
a9fee7cd RB |
1446 | else if (operand_equal_for_phi_arg_p (op1, smaller) |
1447 | || (alt_smaller | |
1448 | && operand_equal_for_phi_arg_p (op1, alt_smaller))) | |
8eaa0f34 ZD |
1449 | bound = op0; |
1450 | else | |
1451 | return false; | |
1452 | ||
1453 | /* We need BOUND >= LARGER. */ | |
987b67bc KH |
1454 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
1455 | bound, larger))) | |
8eaa0f34 ZD |
1456 | return false; |
1457 | } | |
a9fee7cd RB |
1458 | else if (operand_equal_for_phi_arg_p (arg_true, smaller) |
1459 | || (alt_smaller | |
1460 | && operand_equal_for_phi_arg_p (arg_true, alt_smaller))) | |
8eaa0f34 ZD |
1461 | { |
1462 | /* Case | |
1463 | ||
1464 | if (smaller > larger) | |
1465 | { | |
1466 | r' = MAX_EXPR (larger, bound) | |
1467 | } | |
1468 | r = PHI <r', smaller> --> to be turned to MIN_EXPR. */ | |
1469 | if (ass_code != MAX_EXPR) | |
1470 | return false; | |
1471 | ||
1472 | minmax = MIN_EXPR; | |
1473 | if (operand_equal_for_phi_arg_p (op0, larger)) | |
1474 | bound = op1; | |
1475 | else if (operand_equal_for_phi_arg_p (op1, larger)) | |
1476 | bound = op0; | |
1477 | else | |
1478 | return false; | |
1479 | ||
1480 | /* We need BOUND <= SMALLER. */ | |
987b67bc KH |
1481 | if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node, |
1482 | bound, smaller))) | |
8eaa0f34 ZD |
1483 | return false; |
1484 | } | |
1485 | else | |
1486 | return false; | |
1487 | } | |
1488 | ||
1489 | /* Move the statement from the middle block. */ | |
726a989a | 1490 | gsi = gsi_last_bb (cond_bb); |
21719cea | 1491 | gsi_from = gsi_last_nondebug_bb (middle_bb); |
5a40ae3c RB |
1492 | reset_flow_sensitive_info (SINGLE_SSA_TREE_OPERAND (gsi_stmt (gsi_from), |
1493 | SSA_OP_DEF)); | |
726a989a | 1494 | gsi_move_before (&gsi_from, &gsi); |
8eaa0f34 ZD |
1495 | } |
1496 | ||
a6810021 NS |
1497 | /* Create an SSA var to hold the min/max result. If we're the only |
1498 | things setting the target PHI, then we can clone the PHI | |
1499 | variable. Otherwise we must create a new one. */ | |
1500 | result = PHI_RESULT (phi); | |
1501 | if (EDGE_COUNT (gimple_bb (phi)->preds) == 2) | |
1502 | result = duplicate_ssa_name (result, NULL); | |
1503 | else | |
1504 | result = make_ssa_name (TREE_TYPE (result)); | |
1505 | ||
8eaa0f34 | 1506 | /* Emit the statement to compute min/max. */ |
0d0e4a03 | 1507 | new_stmt = gimple_build_assign (result, minmax, arg0, arg1); |
726a989a RB |
1508 | gsi = gsi_last_bb (cond_bb); |
1509 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
8eaa0f34 | 1510 | |
e5206274 | 1511 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
9edaabf3 | 1512 | |
8eaa0f34 ZD |
1513 | return true; |
1514 | } | |
1515 | ||
cc52902d AP |
1516 | /* The function absolute_replacement does the main work of doing the absolute |
1517 | replacement. Return true if the replacement is done. Otherwise return | |
1518 | false. | |
1519 | bb is the basic block where the replacement is going to be done on. arg0 | |
6c6cfbfd | 1520 | is argument 0 from the phi. Likewise for arg1. */ |
80c4ed35 | 1521 | |
cc52902d | 1522 | static bool |
80c4ed35 | 1523 | abs_replacement (basic_block cond_bb, basic_block middle_bb, |
e5206274 | 1524 | edge e0 ATTRIBUTE_UNUSED, edge e1, |
355fe088 | 1525 | gimple *phi, tree arg0, tree arg1) |
cc52902d AP |
1526 | { |
1527 | tree result; | |
538dd0b7 | 1528 | gassign *new_stmt; |
355fe088 | 1529 | gimple *cond; |
726a989a | 1530 | gimple_stmt_iterator gsi; |
cc52902d | 1531 | edge true_edge, false_edge; |
355fe088 | 1532 | gimple *assign; |
cc52902d | 1533 | edge e; |
8eaa0f34 | 1534 | tree rhs, lhs; |
cc52902d AP |
1535 | bool negate; |
1536 | enum tree_code cond_code; | |
1537 | ||
1538 | /* If the type says honor signed zeros we cannot do this | |
471854f8 | 1539 | optimization. */ |
3d3dbadd | 1540 | if (HONOR_SIGNED_ZEROS (arg1)) |
cc52902d AP |
1541 | return false; |
1542 | ||
cc52902d AP |
1543 | /* OTHER_BLOCK must have only one executable statement which must have the |
1544 | form arg0 = -arg1 or arg1 = -arg0. */ | |
cc52902d | 1545 | |
8eaa0f34 | 1546 | assign = last_and_only_stmt (middle_bb); |
cc52902d AP |
1547 | /* If we did not find the proper negation assignment, then we can not |
1548 | optimize. */ | |
1549 | if (assign == NULL) | |
1550 | return false; | |
b8698a0f | 1551 | |
8eaa0f34 ZD |
1552 | /* If we got here, then we have found the only executable statement |
1553 | in OTHER_BLOCK. If it is anything other than arg = -arg1 or | |
1554 | arg1 = -arg0, then we can not optimize. */ | |
726a989a | 1555 | if (gimple_code (assign) != GIMPLE_ASSIGN) |
8eaa0f34 ZD |
1556 | return false; |
1557 | ||
726a989a | 1558 | lhs = gimple_assign_lhs (assign); |
8eaa0f34 | 1559 | |
726a989a | 1560 | if (gimple_assign_rhs_code (assign) != NEGATE_EXPR) |
8eaa0f34 ZD |
1561 | return false; |
1562 | ||
726a989a | 1563 | rhs = gimple_assign_rhs1 (assign); |
b8698a0f | 1564 | |
8eaa0f34 ZD |
1565 | /* The assignment has to be arg0 = -arg1 or arg1 = -arg0. */ |
1566 | if (!(lhs == arg0 && rhs == arg1) | |
1567 | && !(lhs == arg1 && rhs == arg0)) | |
1568 | return false; | |
cc52902d | 1569 | |
726a989a | 1570 | cond = last_stmt (cond_bb); |
cc52902d AP |
1571 | result = PHI_RESULT (phi); |
1572 | ||
1573 | /* Only relationals comparing arg[01] against zero are interesting. */ | |
726a989a | 1574 | cond_code = gimple_cond_code (cond); |
cc52902d AP |
1575 | if (cond_code != GT_EXPR && cond_code != GE_EXPR |
1576 | && cond_code != LT_EXPR && cond_code != LE_EXPR) | |
1577 | return false; | |
1578 | ||
471854f8 | 1579 | /* Make sure the conditional is arg[01] OP y. */ |
726a989a | 1580 | if (gimple_cond_lhs (cond) != rhs) |
cc52902d AP |
1581 | return false; |
1582 | ||
726a989a RB |
1583 | if (FLOAT_TYPE_P (TREE_TYPE (gimple_cond_rhs (cond))) |
1584 | ? real_zerop (gimple_cond_rhs (cond)) | |
1585 | : integer_zerop (gimple_cond_rhs (cond))) | |
cc52902d AP |
1586 | ; |
1587 | else | |
1588 | return false; | |
1589 | ||
1590 | /* We need to know which is the true edge and which is the false | |
1591 | edge so that we know if have abs or negative abs. */ | |
80c4ed35 | 1592 | extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); |
cc52902d AP |
1593 | |
1594 | /* For GT_EXPR/GE_EXPR, if the true edge goes to OTHER_BLOCK, then we | |
1595 | will need to negate the result. Similarly for LT_EXPR/LE_EXPR if | |
1596 | the false edge goes to OTHER_BLOCK. */ | |
1597 | if (cond_code == GT_EXPR || cond_code == GE_EXPR) | |
1598 | e = true_edge; | |
1599 | else | |
1600 | e = false_edge; | |
0385f644 | 1601 | |
80c4ed35 | 1602 | if (e->dest == middle_bb) |
cc52902d AP |
1603 | negate = true; |
1604 | else | |
1605 | negate = false; | |
0385f644 | 1606 | |
32894793 RB |
1607 | /* If the code negates only iff positive then make sure to not |
1608 | introduce undefined behavior when negating or computing the absolute. | |
1609 | ??? We could use range info if present to check for arg1 == INT_MIN. */ | |
1610 | if (negate | |
1611 | && (ANY_INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
1612 | && ! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1)))) | |
1613 | return false; | |
1614 | ||
80c4ed35 | 1615 | result = duplicate_ssa_name (result, NULL); |
0385f644 | 1616 | |
cc52902d | 1617 | if (negate) |
b731b390 | 1618 | lhs = make_ssa_name (TREE_TYPE (result)); |
cc52902d AP |
1619 | else |
1620 | lhs = result; | |
1621 | ||
471854f8 | 1622 | /* Build the modify expression with abs expression. */ |
0d0e4a03 | 1623 | new_stmt = gimple_build_assign (lhs, ABS_EXPR, rhs); |
cc52902d | 1624 | |
726a989a RB |
1625 | gsi = gsi_last_bb (cond_bb); |
1626 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
cc52902d AP |
1627 | |
1628 | if (negate) | |
1629 | { | |
726a989a | 1630 | /* Get the right GSI. We want to insert after the recently |
cc52902d AP |
1631 | added ABS_EXPR statement (which we know is the first statement |
1632 | in the block. */ | |
0d0e4a03 | 1633 | new_stmt = gimple_build_assign (result, NEGATE_EXPR, lhs); |
cc52902d | 1634 | |
726a989a | 1635 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); |
cc52902d | 1636 | } |
0385f644 | 1637 | |
e5206274 | 1638 | replace_phi_edge_with_variable (cond_bb, e1, phi, result); |
cc52902d AP |
1639 | |
1640 | /* Note that we optimized this PHI. */ | |
1641 | return true; | |
1642 | } | |
1643 | ||
a5828d1e MM |
1644 | /* Auxiliary functions to determine the set of memory accesses which |
1645 | can't trap because they are preceded by accesses to the same memory | |
70f34814 | 1646 | portion. We do that for MEM_REFs, so we only need to track |
a5828d1e MM |
1647 | the SSA_NAME of the pointer indirectly referenced. The algorithm |
1648 | simply is a walk over all instructions in dominator order. When | |
70f34814 | 1649 | we see an MEM_REF we determine if we've already seen a same |
a5828d1e | 1650 | ref anywhere up to the root of the dominator tree. If we do the |
e08f02f0 | 1651 | current access can't trap. If we don't see any dominating access |
a5828d1e | 1652 | the current access might trap, but might also make later accesses |
e08f02f0 MM |
1653 | non-trapping, so we remember it. We need to be careful with loads |
1654 | or stores, for instance a load might not trap, while a store would, | |
1655 | so if we see a dominating read access this doesn't mean that a later | |
1656 | write access would not trap. Hence we also need to differentiate the | |
1657 | type of access(es) seen. | |
1658 | ||
1659 | ??? We currently are very conservative and assume that a load might | |
1660 | trap even if a store doesn't (write-only memory). This probably is | |
1661 | overly conservative. */ | |
a5828d1e | 1662 | |
70f34814 | 1663 | /* A hash-table of SSA_NAMEs, and in which basic block an MEM_REF |
a5828d1e MM |
1664 | through it was seen, which would constitute a no-trap region for |
1665 | same accesses. */ | |
1666 | struct name_to_bb | |
1667 | { | |
69ef9a79 | 1668 | unsigned int ssa_name_ver; |
c1ca73d8 | 1669 | unsigned int phase; |
69ef9a79 JJ |
1670 | bool store; |
1671 | HOST_WIDE_INT offset, size; | |
a5828d1e MM |
1672 | basic_block bb; |
1673 | }; | |
1674 | ||
4a8fb1a1 LC |
1675 | /* Hashtable helpers. */ |
1676 | ||
95fbe13e | 1677 | struct ssa_names_hasher : free_ptr_hash <name_to_bb> |
4a8fb1a1 | 1678 | { |
67f58944 TS |
1679 | static inline hashval_t hash (const name_to_bb *); |
1680 | static inline bool equal (const name_to_bb *, const name_to_bb *); | |
4a8fb1a1 | 1681 | }; |
a5828d1e | 1682 | |
c1ca73d8 MM |
1683 | /* Used for quick clearing of the hash-table when we see calls. |
1684 | Hash entries with phase < nt_call_phase are invalid. */ | |
1685 | static unsigned int nt_call_phase; | |
1686 | ||
69ef9a79 | 1687 | /* The hash function. */ |
4a8fb1a1 LC |
1688 | |
1689 | inline hashval_t | |
67f58944 | 1690 | ssa_names_hasher::hash (const name_to_bb *n) |
a5828d1e | 1691 | { |
69ef9a79 JJ |
1692 | return n->ssa_name_ver ^ (((hashval_t) n->store) << 31) |
1693 | ^ (n->offset << 6) ^ (n->size << 3); | |
a5828d1e MM |
1694 | } |
1695 | ||
69ef9a79 | 1696 | /* The equality function of *P1 and *P2. */ |
a5828d1e | 1697 | |
4a8fb1a1 | 1698 | inline bool |
67f58944 | 1699 | ssa_names_hasher::equal (const name_to_bb *n1, const name_to_bb *n2) |
4a8fb1a1 | 1700 | { |
69ef9a79 JJ |
1701 | return n1->ssa_name_ver == n2->ssa_name_ver |
1702 | && n1->store == n2->store | |
1703 | && n1->offset == n2->offset | |
1704 | && n1->size == n2->size; | |
a5828d1e MM |
1705 | } |
1706 | ||
c203e8a7 TS |
1707 | class nontrapping_dom_walker : public dom_walker |
1708 | { | |
1709 | public: | |
6e2830c3 | 1710 | nontrapping_dom_walker (cdi_direction direction, hash_set<tree> *ps) |
c203e8a7 TS |
1711 | : dom_walker (direction), m_nontrapping (ps), m_seen_ssa_names (128) {} |
1712 | ||
3daacdcd | 1713 | virtual edge before_dom_children (basic_block); |
c203e8a7 TS |
1714 | virtual void after_dom_children (basic_block); |
1715 | ||
1716 | private: | |
1717 | ||
1718 | /* We see the expression EXP in basic block BB. If it's an interesting | |
1719 | expression (an MEM_REF through an SSA_NAME) possibly insert the | |
1720 | expression into the set NONTRAP or the hash table of seen expressions. | |
1721 | STORE is true if this expression is on the LHS, otherwise it's on | |
1722 | the RHS. */ | |
1723 | void add_or_mark_expr (basic_block, tree, bool); | |
1724 | ||
6e2830c3 | 1725 | hash_set<tree> *m_nontrapping; |
c203e8a7 TS |
1726 | |
1727 | /* The hash table for remembering what we've seen. */ | |
1728 | hash_table<ssa_names_hasher> m_seen_ssa_names; | |
1729 | }; | |
1730 | ||
1731 | /* Called by walk_dominator_tree, when entering the block BB. */ | |
3daacdcd | 1732 | edge |
c203e8a7 TS |
1733 | nontrapping_dom_walker::before_dom_children (basic_block bb) |
1734 | { | |
1735 | edge e; | |
1736 | edge_iterator ei; | |
1737 | gimple_stmt_iterator gsi; | |
1738 | ||
1739 | /* If we haven't seen all our predecessors, clear the hash-table. */ | |
1740 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1741 | if ((((size_t)e->src->aux) & 2) == 0) | |
1742 | { | |
1743 | nt_call_phase++; | |
1744 | break; | |
1745 | } | |
1746 | ||
1747 | /* Mark this BB as being on the path to dominator root and as visited. */ | |
1748 | bb->aux = (void*)(1 | 2); | |
1749 | ||
1750 | /* And walk the statements in order. */ | |
1751 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1752 | { | |
355fe088 | 1753 | gimple *stmt = gsi_stmt (gsi); |
c203e8a7 | 1754 | |
c000cd7c BS |
1755 | if ((gimple_code (stmt) == GIMPLE_ASM && gimple_vdef (stmt)) |
1756 | || (is_gimple_call (stmt) | |
1757 | && (!nonfreeing_call_p (stmt) || !nonbarrier_call_p (stmt)))) | |
c203e8a7 TS |
1758 | nt_call_phase++; |
1759 | else if (gimple_assign_single_p (stmt) && !gimple_has_volatile_ops (stmt)) | |
1760 | { | |
1761 | add_or_mark_expr (bb, gimple_assign_lhs (stmt), true); | |
1762 | add_or_mark_expr (bb, gimple_assign_rhs1 (stmt), false); | |
1763 | } | |
1764 | } | |
3daacdcd | 1765 | return NULL; |
c203e8a7 TS |
1766 | } |
1767 | ||
1768 | /* Called by walk_dominator_tree, when basic block BB is exited. */ | |
1769 | void | |
1770 | nontrapping_dom_walker::after_dom_children (basic_block bb) | |
1771 | { | |
1772 | /* This BB isn't on the path to dominator root anymore. */ | |
1773 | bb->aux = (void*)2; | |
1774 | } | |
4a8fb1a1 | 1775 | |
fa10beec | 1776 | /* We see the expression EXP in basic block BB. If it's an interesting |
70f34814 | 1777 | expression (an MEM_REF through an SSA_NAME) possibly insert the |
e08f02f0 MM |
1778 | expression into the set NONTRAP or the hash table of seen expressions. |
1779 | STORE is true if this expression is on the LHS, otherwise it's on | |
1780 | the RHS. */ | |
c203e8a7 TS |
1781 | void |
1782 | nontrapping_dom_walker::add_or_mark_expr (basic_block bb, tree exp, bool store) | |
a5828d1e | 1783 | { |
69ef9a79 JJ |
1784 | HOST_WIDE_INT size; |
1785 | ||
70f34814 | 1786 | if (TREE_CODE (exp) == MEM_REF |
69ef9a79 | 1787 | && TREE_CODE (TREE_OPERAND (exp, 0)) == SSA_NAME |
9541ffee | 1788 | && tree_fits_shwi_p (TREE_OPERAND (exp, 1)) |
69ef9a79 | 1789 | && (size = int_size_in_bytes (TREE_TYPE (exp))) > 0) |
a5828d1e MM |
1790 | { |
1791 | tree name = TREE_OPERAND (exp, 0); | |
1792 | struct name_to_bb map; | |
4a8fb1a1 | 1793 | name_to_bb **slot; |
e08f02f0 | 1794 | struct name_to_bb *n2bb; |
a5828d1e MM |
1795 | basic_block found_bb = 0; |
1796 | ||
70f34814 | 1797 | /* Try to find the last seen MEM_REF through the same |
a5828d1e | 1798 | SSA_NAME, which can trap. */ |
69ef9a79 | 1799 | map.ssa_name_ver = SSA_NAME_VERSION (name); |
c1ca73d8 | 1800 | map.phase = 0; |
a5828d1e | 1801 | map.bb = 0; |
e08f02f0 | 1802 | map.store = store; |
9439e9a1 | 1803 | map.offset = tree_to_shwi (TREE_OPERAND (exp, 1)); |
69ef9a79 JJ |
1804 | map.size = size; |
1805 | ||
c203e8a7 | 1806 | slot = m_seen_ssa_names.find_slot (&map, INSERT); |
4a8fb1a1 | 1807 | n2bb = *slot; |
c1ca73d8 | 1808 | if (n2bb && n2bb->phase >= nt_call_phase) |
e08f02f0 | 1809 | found_bb = n2bb->bb; |
a5828d1e | 1810 | |
70f34814 | 1811 | /* If we've found a trapping MEM_REF, _and_ it dominates EXP |
a5828d1e MM |
1812 | (it's in a basic block on the path from us to the dominator root) |
1813 | then we can't trap. */ | |
c1ca73d8 | 1814 | if (found_bb && (((size_t)found_bb->aux) & 1) == 1) |
a5828d1e | 1815 | { |
6e2830c3 | 1816 | m_nontrapping->add (exp); |
a5828d1e MM |
1817 | } |
1818 | else | |
1819 | { | |
1820 | /* EXP might trap, so insert it into the hash table. */ | |
e08f02f0 | 1821 | if (n2bb) |
a5828d1e | 1822 | { |
c1ca73d8 | 1823 | n2bb->phase = nt_call_phase; |
e08f02f0 | 1824 | n2bb->bb = bb; |
a5828d1e MM |
1825 | } |
1826 | else | |
1827 | { | |
e08f02f0 | 1828 | n2bb = XNEW (struct name_to_bb); |
69ef9a79 | 1829 | n2bb->ssa_name_ver = SSA_NAME_VERSION (name); |
c1ca73d8 | 1830 | n2bb->phase = nt_call_phase; |
e08f02f0 MM |
1831 | n2bb->bb = bb; |
1832 | n2bb->store = store; | |
69ef9a79 JJ |
1833 | n2bb->offset = map.offset; |
1834 | n2bb->size = size; | |
e08f02f0 | 1835 | *slot = n2bb; |
a5828d1e MM |
1836 | } |
1837 | } | |
1838 | } | |
1839 | } | |
1840 | ||
a5828d1e MM |
1841 | /* This is the entry point of gathering non trapping memory accesses. |
1842 | It will do a dominator walk over the whole function, and it will | |
1843 | make use of the bb->aux pointers. It returns a set of trees | |
70f34814 | 1844 | (the MEM_REFs itself) which can't trap. */ |
6e2830c3 | 1845 | static hash_set<tree> * |
a5828d1e MM |
1846 | get_non_trapping (void) |
1847 | { | |
c1ca73d8 | 1848 | nt_call_phase = 0; |
6e2830c3 | 1849 | hash_set<tree> *nontrap = new hash_set<tree>; |
a5828d1e MM |
1850 | /* We're going to do a dominator walk, so ensure that we have |
1851 | dominance information. */ | |
1852 | calculate_dominance_info (CDI_DOMINATORS); | |
1853 | ||
4d9192b5 TS |
1854 | nontrapping_dom_walker (CDI_DOMINATORS, nontrap) |
1855 | .walk (cfun->cfg->x_entry_block_ptr); | |
1856 | ||
c1ca73d8 | 1857 | clear_aux_for_blocks (); |
a5828d1e MM |
1858 | return nontrap; |
1859 | } | |
1860 | ||
1861 | /* Do the main work of conditional store replacement. We already know | |
1862 | that the recognized pattern looks like so: | |
1863 | ||
1864 | split: | |
1865 | if (cond) goto MIDDLE_BB; else goto JOIN_BB (edge E1) | |
1866 | MIDDLE_BB: | |
1867 | something | |
1868 | fallthrough (edge E0) | |
1869 | JOIN_BB: | |
1870 | some more | |
1871 | ||
1872 | We check that MIDDLE_BB contains only one store, that that store | |
1873 | doesn't trap (not via NOTRAP, but via checking if an access to the same | |
1874 | memory location dominates us) and that the store has a "simple" RHS. */ | |
1875 | ||
1876 | static bool | |
1877 | cond_store_replacement (basic_block middle_bb, basic_block join_bb, | |
6e2830c3 | 1878 | edge e0, edge e1, hash_set<tree> *nontrap) |
a5828d1e | 1879 | { |
355fe088 | 1880 | gimple *assign = last_and_only_stmt (middle_bb); |
83d5977e | 1881 | tree lhs, rhs, name, name2; |
538dd0b7 DM |
1882 | gphi *newphi; |
1883 | gassign *new_stmt; | |
726a989a | 1884 | gimple_stmt_iterator gsi; |
f5045c96 | 1885 | source_location locus; |
a5828d1e MM |
1886 | |
1887 | /* Check if middle_bb contains of only one store. */ | |
1888 | if (!assign | |
d7fa6ee2 JJ |
1889 | || !gimple_assign_single_p (assign) |
1890 | || gimple_has_volatile_ops (assign)) | |
a5828d1e MM |
1891 | return false; |
1892 | ||
f5045c96 | 1893 | locus = gimple_location (assign); |
726a989a RB |
1894 | lhs = gimple_assign_lhs (assign); |
1895 | rhs = gimple_assign_rhs1 (assign); | |
70f34814 | 1896 | if (TREE_CODE (lhs) != MEM_REF |
23782cc3 | 1897 | || TREE_CODE (TREE_OPERAND (lhs, 0)) != SSA_NAME |
742d143c | 1898 | || !is_gimple_reg_type (TREE_TYPE (lhs))) |
a5828d1e | 1899 | return false; |
23782cc3 | 1900 | |
a5828d1e MM |
1901 | /* Prove that we can move the store down. We could also check |
1902 | TREE_THIS_NOTRAP here, but in that case we also could move stores, | |
1903 | whose value is not available readily, which we want to avoid. */ | |
6e2830c3 | 1904 | if (!nontrap->contains (lhs)) |
a5828d1e MM |
1905 | return false; |
1906 | ||
1907 | /* Now we've checked the constraints, so do the transformation: | |
1908 | 1) Remove the single store. */ | |
726a989a | 1909 | gsi = gsi_for_stmt (assign); |
742d143c | 1910 | unlink_stmt_vdef (assign); |
726a989a | 1911 | gsi_remove (&gsi, true); |
23782cc3 | 1912 | release_defs (assign); |
a5828d1e | 1913 | |
da76b253 RB |
1914 | /* Make both store and load use alias-set zero as we have to |
1915 | deal with the case of the store being a conditional change | |
1916 | of the dynamic type. */ | |
1917 | lhs = unshare_expr (lhs); | |
1918 | tree *basep = &lhs; | |
1919 | while (handled_component_p (*basep)) | |
1920 | basep = &TREE_OPERAND (*basep, 0); | |
1921 | if (TREE_CODE (*basep) == MEM_REF | |
1922 | || TREE_CODE (*basep) == TARGET_MEM_REF) | |
1923 | TREE_OPERAND (*basep, 1) | |
1924 | = fold_convert (ptr_type_node, TREE_OPERAND (*basep, 1)); | |
1925 | else | |
1926 | *basep = build2 (MEM_REF, TREE_TYPE (*basep), | |
1927 | build_fold_addr_expr (*basep), | |
1928 | build_zero_cst (ptr_type_node)); | |
1929 | ||
83d5977e | 1930 | /* 2) Insert a load from the memory of the store to the temporary |
a5828d1e | 1931 | on the edge which did not contain the store. */ |
83d5977e RG |
1932 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1933 | new_stmt = gimple_build_assign (name, lhs); | |
f5045c96 | 1934 | gimple_set_location (new_stmt, locus); |
726a989a | 1935 | gsi_insert_on_edge (e1, new_stmt); |
a5828d1e | 1936 | |
83d5977e | 1937 | /* 3) Create a PHI node at the join block, with one argument |
a5828d1e MM |
1938 | holding the old RHS, and the other holding the temporary |
1939 | where we stored the old memory contents. */ | |
83d5977e RG |
1940 | name2 = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
1941 | newphi = create_phi_node (name2, join_bb); | |
9e227d60 DC |
1942 | add_phi_arg (newphi, rhs, e0, locus); |
1943 | add_phi_arg (newphi, name, e1, locus); | |
a5828d1e MM |
1944 | |
1945 | lhs = unshare_expr (lhs); | |
726a989a | 1946 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); |
a5828d1e | 1947 | |
83d5977e | 1948 | /* 4) Insert that PHI node. */ |
726a989a RB |
1949 | gsi = gsi_after_labels (join_bb); |
1950 | if (gsi_end_p (gsi)) | |
a5828d1e | 1951 | { |
726a989a RB |
1952 | gsi = gsi_last_bb (join_bb); |
1953 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
a5828d1e MM |
1954 | } |
1955 | else | |
726a989a | 1956 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); |
a5828d1e MM |
1957 | |
1958 | return true; | |
1959 | } | |
6de9cd9a | 1960 | |
bfe068c3 | 1961 | /* Do the main work of conditional store replacement. */ |
23782cc3 JJ |
1962 | |
1963 | static bool | |
bfe068c3 | 1964 | cond_if_else_store_replacement_1 (basic_block then_bb, basic_block else_bb, |
355fe088 TS |
1965 | basic_block join_bb, gimple *then_assign, |
1966 | gimple *else_assign) | |
23782cc3 | 1967 | { |
83d5977e | 1968 | tree lhs_base, lhs, then_rhs, else_rhs, name; |
23782cc3 JJ |
1969 | source_location then_locus, else_locus; |
1970 | gimple_stmt_iterator gsi; | |
538dd0b7 DM |
1971 | gphi *newphi; |
1972 | gassign *new_stmt; | |
23782cc3 | 1973 | |
23782cc3 JJ |
1974 | if (then_assign == NULL |
1975 | || !gimple_assign_single_p (then_assign) | |
47598145 | 1976 | || gimple_clobber_p (then_assign) |
d7fa6ee2 | 1977 | || gimple_has_volatile_ops (then_assign) |
23782cc3 | 1978 | || else_assign == NULL |
47598145 | 1979 | || !gimple_assign_single_p (else_assign) |
d7fa6ee2 JJ |
1980 | || gimple_clobber_p (else_assign) |
1981 | || gimple_has_volatile_ops (else_assign)) | |
23782cc3 JJ |
1982 | return false; |
1983 | ||
1984 | lhs = gimple_assign_lhs (then_assign); | |
1985 | if (!is_gimple_reg_type (TREE_TYPE (lhs)) | |
1986 | || !operand_equal_p (lhs, gimple_assign_lhs (else_assign), 0)) | |
1987 | return false; | |
1988 | ||
1989 | lhs_base = get_base_address (lhs); | |
1990 | if (lhs_base == NULL_TREE | |
1991 | || (!DECL_P (lhs_base) && TREE_CODE (lhs_base) != MEM_REF)) | |
1992 | return false; | |
1993 | ||
1994 | then_rhs = gimple_assign_rhs1 (then_assign); | |
1995 | else_rhs = gimple_assign_rhs1 (else_assign); | |
1996 | then_locus = gimple_location (then_assign); | |
1997 | else_locus = gimple_location (else_assign); | |
1998 | ||
1999 | /* Now we've checked the constraints, so do the transformation: | |
2000 | 1) Remove the stores. */ | |
2001 | gsi = gsi_for_stmt (then_assign); | |
2002 | unlink_stmt_vdef (then_assign); | |
2003 | gsi_remove (&gsi, true); | |
2004 | release_defs (then_assign); | |
2005 | ||
2006 | gsi = gsi_for_stmt (else_assign); | |
2007 | unlink_stmt_vdef (else_assign); | |
2008 | gsi_remove (&gsi, true); | |
2009 | release_defs (else_assign); | |
2010 | ||
83d5977e | 2011 | /* 2) Create a PHI node at the join block, with one argument |
23782cc3 JJ |
2012 | holding the old RHS, and the other holding the temporary |
2013 | where we stored the old memory contents. */ | |
83d5977e RG |
2014 | name = make_temp_ssa_name (TREE_TYPE (lhs), NULL, "cstore"); |
2015 | newphi = create_phi_node (name, join_bb); | |
9e227d60 DC |
2016 | add_phi_arg (newphi, then_rhs, EDGE_SUCC (then_bb, 0), then_locus); |
2017 | add_phi_arg (newphi, else_rhs, EDGE_SUCC (else_bb, 0), else_locus); | |
23782cc3 JJ |
2018 | |
2019 | new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi)); | |
2020 | ||
83d5977e | 2021 | /* 3) Insert that PHI node. */ |
23782cc3 JJ |
2022 | gsi = gsi_after_labels (join_bb); |
2023 | if (gsi_end_p (gsi)) | |
2024 | { | |
2025 | gsi = gsi_last_bb (join_bb); | |
2026 | gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT); | |
2027 | } | |
2028 | else | |
2029 | gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT); | |
2030 | ||
2031 | return true; | |
2032 | } | |
2033 | ||
bfe068c3 IR |
2034 | /* Conditional store replacement. We already know |
2035 | that the recognized pattern looks like so: | |
2036 | ||
2037 | split: | |
2038 | if (cond) goto THEN_BB; else goto ELSE_BB (edge E1) | |
2039 | THEN_BB: | |
2040 | ... | |
2041 | X = Y; | |
2042 | ... | |
2043 | goto JOIN_BB; | |
2044 | ELSE_BB: | |
2045 | ... | |
2046 | X = Z; | |
2047 | ... | |
2048 | fallthrough (edge E0) | |
2049 | JOIN_BB: | |
2050 | some more | |
2051 | ||
2052 | We check that it is safe to sink the store to JOIN_BB by verifying that | |
2053 | there are no read-after-write or write-after-write dependencies in | |
2054 | THEN_BB and ELSE_BB. */ | |
2055 | ||
2056 | static bool | |
2057 | cond_if_else_store_replacement (basic_block then_bb, basic_block else_bb, | |
2058 | basic_block join_bb) | |
2059 | { | |
355fe088 TS |
2060 | gimple *then_assign = last_and_only_stmt (then_bb); |
2061 | gimple *else_assign = last_and_only_stmt (else_bb); | |
9771b263 DN |
2062 | vec<data_reference_p> then_datarefs, else_datarefs; |
2063 | vec<ddr_p> then_ddrs, else_ddrs; | |
355fe088 | 2064 | gimple *then_store, *else_store; |
bfe068c3 IR |
2065 | bool found, ok = false, res; |
2066 | struct data_dependence_relation *ddr; | |
2067 | data_reference_p then_dr, else_dr; | |
2068 | int i, j; | |
2069 | tree then_lhs, else_lhs; | |
bfe068c3 IR |
2070 | basic_block blocks[3]; |
2071 | ||
2072 | if (MAX_STORES_TO_SINK == 0) | |
2073 | return false; | |
2074 | ||
2075 | /* Handle the case with single statement in THEN_BB and ELSE_BB. */ | |
2076 | if (then_assign && else_assign) | |
2077 | return cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, | |
2078 | then_assign, else_assign); | |
2079 | ||
2080 | /* Find data references. */ | |
9771b263 DN |
2081 | then_datarefs.create (1); |
2082 | else_datarefs.create (1); | |
bfe068c3 IR |
2083 | if ((find_data_references_in_bb (NULL, then_bb, &then_datarefs) |
2084 | == chrec_dont_know) | |
9771b263 | 2085 | || !then_datarefs.length () |
bfe068c3 | 2086 | || (find_data_references_in_bb (NULL, else_bb, &else_datarefs) |
5ce9450f | 2087 | == chrec_dont_know) |
9771b263 | 2088 | || !else_datarefs.length ()) |
bfe068c3 IR |
2089 | { |
2090 | free_data_refs (then_datarefs); | |
2091 | free_data_refs (else_datarefs); | |
2092 | return false; | |
2093 | } | |
2094 | ||
2095 | /* Find pairs of stores with equal LHS. */ | |
355fe088 | 2096 | auto_vec<gimple *, 1> then_stores, else_stores; |
9771b263 | 2097 | FOR_EACH_VEC_ELT (then_datarefs, i, then_dr) |
bfe068c3 IR |
2098 | { |
2099 | if (DR_IS_READ (then_dr)) | |
2100 | continue; | |
2101 | ||
2102 | then_store = DR_STMT (then_dr); | |
59daeef4 | 2103 | then_lhs = gimple_get_lhs (then_store); |
5ce9450f JJ |
2104 | if (then_lhs == NULL_TREE) |
2105 | continue; | |
bfe068c3 IR |
2106 | found = false; |
2107 | ||
9771b263 | 2108 | FOR_EACH_VEC_ELT (else_datarefs, j, else_dr) |
bfe068c3 IR |
2109 | { |
2110 | if (DR_IS_READ (else_dr)) | |
2111 | continue; | |
2112 | ||
2113 | else_store = DR_STMT (else_dr); | |
59daeef4 | 2114 | else_lhs = gimple_get_lhs (else_store); |
5ce9450f JJ |
2115 | if (else_lhs == NULL_TREE) |
2116 | continue; | |
bfe068c3 IR |
2117 | |
2118 | if (operand_equal_p (then_lhs, else_lhs, 0)) | |
2119 | { | |
2120 | found = true; | |
2121 | break; | |
2122 | } | |
2123 | } | |
2124 | ||
2125 | if (!found) | |
2126 | continue; | |
2127 | ||
9771b263 DN |
2128 | then_stores.safe_push (then_store); |
2129 | else_stores.safe_push (else_store); | |
bfe068c3 IR |
2130 | } |
2131 | ||
2132 | /* No pairs of stores found. */ | |
9771b263 DN |
2133 | if (!then_stores.length () |
2134 | || then_stores.length () > (unsigned) MAX_STORES_TO_SINK) | |
bfe068c3 IR |
2135 | { |
2136 | free_data_refs (then_datarefs); | |
2137 | free_data_refs (else_datarefs); | |
bfe068c3 IR |
2138 | return false; |
2139 | } | |
2140 | ||
2141 | /* Compute and check data dependencies in both basic blocks. */ | |
9771b263 DN |
2142 | then_ddrs.create (1); |
2143 | else_ddrs.create (1); | |
2144 | if (!compute_all_dependences (then_datarefs, &then_ddrs, | |
6e1aa848 | 2145 | vNULL, false) |
9771b263 | 2146 | || !compute_all_dependences (else_datarefs, &else_ddrs, |
6e1aa848 | 2147 | vNULL, false)) |
795e8869 JJ |
2148 | { |
2149 | free_dependence_relations (then_ddrs); | |
2150 | free_dependence_relations (else_ddrs); | |
2151 | free_data_refs (then_datarefs); | |
2152 | free_data_refs (else_datarefs); | |
795e8869 JJ |
2153 | return false; |
2154 | } | |
bfe068c3 IR |
2155 | blocks[0] = then_bb; |
2156 | blocks[1] = else_bb; | |
2157 | blocks[2] = join_bb; | |
2158 | renumber_gimple_stmt_uids_in_blocks (blocks, 3); | |
2159 | ||
2160 | /* Check that there are no read-after-write or write-after-write dependencies | |
2161 | in THEN_BB. */ | |
9771b263 | 2162 | FOR_EACH_VEC_ELT (then_ddrs, i, ddr) |
bfe068c3 IR |
2163 | { |
2164 | struct data_reference *dra = DDR_A (ddr); | |
2165 | struct data_reference *drb = DDR_B (ddr); | |
2166 | ||
2167 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
2168 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
2169 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
2170 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
2171 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
2172 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
2173 | { | |
2174 | free_dependence_relations (then_ddrs); | |
2175 | free_dependence_relations (else_ddrs); | |
dbaa912c RG |
2176 | free_data_refs (then_datarefs); |
2177 | free_data_refs (else_datarefs); | |
bfe068c3 IR |
2178 | return false; |
2179 | } | |
2180 | } | |
2181 | ||
2182 | /* Check that there are no read-after-write or write-after-write dependencies | |
2183 | in ELSE_BB. */ | |
9771b263 | 2184 | FOR_EACH_VEC_ELT (else_ddrs, i, ddr) |
bfe068c3 IR |
2185 | { |
2186 | struct data_reference *dra = DDR_A (ddr); | |
2187 | struct data_reference *drb = DDR_B (ddr); | |
2188 | ||
2189 | if (DDR_ARE_DEPENDENT (ddr) != chrec_known | |
2190 | && ((DR_IS_READ (dra) && DR_IS_WRITE (drb) | |
2191 | && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb))) | |
2192 | || (DR_IS_READ (drb) && DR_IS_WRITE (dra) | |
2193 | && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra))) | |
2194 | || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb)))) | |
2195 | { | |
2196 | free_dependence_relations (then_ddrs); | |
2197 | free_dependence_relations (else_ddrs); | |
dbaa912c RG |
2198 | free_data_refs (then_datarefs); |
2199 | free_data_refs (else_datarefs); | |
bfe068c3 IR |
2200 | return false; |
2201 | } | |
2202 | } | |
2203 | ||
2204 | /* Sink stores with same LHS. */ | |
9771b263 | 2205 | FOR_EACH_VEC_ELT (then_stores, i, then_store) |
bfe068c3 | 2206 | { |
9771b263 | 2207 | else_store = else_stores[i]; |
bfe068c3 IR |
2208 | res = cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb, |
2209 | then_store, else_store); | |
2210 | ok = ok || res; | |
2211 | } | |
2212 | ||
2213 | free_dependence_relations (then_ddrs); | |
2214 | free_dependence_relations (else_ddrs); | |
dbaa912c RG |
2215 | free_data_refs (then_datarefs); |
2216 | free_data_refs (else_datarefs); | |
bfe068c3 IR |
2217 | |
2218 | return ok; | |
2219 | } | |
2220 | ||
372a6eb8 BS |
2221 | /* Return TRUE if STMT has a VUSE whose corresponding VDEF is in BB. */ |
2222 | ||
2223 | static bool | |
355fe088 | 2224 | local_mem_dependence (gimple *stmt, basic_block bb) |
372a6eb8 BS |
2225 | { |
2226 | tree vuse = gimple_vuse (stmt); | |
355fe088 | 2227 | gimple *def; |
372a6eb8 BS |
2228 | |
2229 | if (!vuse) | |
2230 | return false; | |
2231 | ||
2232 | def = SSA_NAME_DEF_STMT (vuse); | |
2233 | return (def && gimple_bb (def) == bb); | |
2234 | } | |
2235 | ||
2236 | /* Given a "diamond" control-flow pattern where BB0 tests a condition, | |
2237 | BB1 and BB2 are "then" and "else" blocks dependent on this test, | |
c9ef86a1 | 2238 | and BB3 rejoins control flow following BB1 and BB2, look for |
372a6eb8 BS |
2239 | opportunities to hoist loads as follows. If BB3 contains a PHI of |
2240 | two loads, one each occurring in BB1 and BB2, and the loads are | |
2241 | provably of adjacent fields in the same structure, then move both | |
2242 | loads into BB0. Of course this can only be done if there are no | |
2243 | dependencies preventing such motion. | |
2244 | ||
2245 | One of the hoisted loads will always be speculative, so the | |
2246 | transformation is currently conservative: | |
2247 | ||
2248 | - The fields must be strictly adjacent. | |
2249 | - The two fields must occupy a single memory block that is | |
2250 | guaranteed to not cross a page boundary. | |
2251 | ||
2252 | The last is difficult to prove, as such memory blocks should be | |
2253 | aligned on the minimum of the stack alignment boundary and the | |
2254 | alignment guaranteed by heap allocation interfaces. Thus we rely | |
2255 | on a parameter for the alignment value. | |
2256 | ||
2257 | Provided a good value is used for the last case, the first | |
2258 | restriction could possibly be relaxed. */ | |
2259 | ||
2260 | static void | |
2261 | hoist_adjacent_loads (basic_block bb0, basic_block bb1, | |
2262 | basic_block bb2, basic_block bb3) | |
2263 | { | |
2264 | int param_align = PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE); | |
2265 | unsigned param_align_bits = (unsigned) (param_align * BITS_PER_UNIT); | |
538dd0b7 | 2266 | gphi_iterator gsi; |
372a6eb8 BS |
2267 | |
2268 | /* Walk the phis in bb3 looking for an opportunity. We are looking | |
2269 | for phis of two SSA names, one each of which is defined in bb1 and | |
2270 | bb2. */ | |
2271 | for (gsi = gsi_start_phis (bb3); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2272 | { | |
538dd0b7 | 2273 | gphi *phi_stmt = gsi.phi (); |
355fe088 | 2274 | gimple *def1, *def2; |
fab27f52 | 2275 | tree arg1, arg2, ref1, ref2, field1, field2; |
372a6eb8 BS |
2276 | tree tree_offset1, tree_offset2, tree_size2, next; |
2277 | int offset1, offset2, size2; | |
2278 | unsigned align1; | |
2279 | gimple_stmt_iterator gsi2; | |
2280 | basic_block bb_for_def1, bb_for_def2; | |
2281 | ||
ea057359 RG |
2282 | if (gimple_phi_num_args (phi_stmt) != 2 |
2283 | || virtual_operand_p (gimple_phi_result (phi_stmt))) | |
372a6eb8 BS |
2284 | continue; |
2285 | ||
2286 | arg1 = gimple_phi_arg_def (phi_stmt, 0); | |
2287 | arg2 = gimple_phi_arg_def (phi_stmt, 1); | |
c9ef86a1 | 2288 | |
372a6eb8 BS |
2289 | if (TREE_CODE (arg1) != SSA_NAME |
2290 | || TREE_CODE (arg2) != SSA_NAME | |
2291 | || SSA_NAME_IS_DEFAULT_DEF (arg1) | |
ea057359 | 2292 | || SSA_NAME_IS_DEFAULT_DEF (arg2)) |
372a6eb8 BS |
2293 | continue; |
2294 | ||
2295 | def1 = SSA_NAME_DEF_STMT (arg1); | |
2296 | def2 = SSA_NAME_DEF_STMT (arg2); | |
2297 | ||
2298 | if ((gimple_bb (def1) != bb1 || gimple_bb (def2) != bb2) | |
2299 | && (gimple_bb (def2) != bb1 || gimple_bb (def1) != bb2)) | |
2300 | continue; | |
2301 | ||
2302 | /* Check the mode of the arguments to be sure a conditional move | |
2303 | can be generated for it. */ | |
0a5f2683 BS |
2304 | if (optab_handler (movcc_optab, TYPE_MODE (TREE_TYPE (arg1))) |
2305 | == CODE_FOR_nothing) | |
372a6eb8 BS |
2306 | continue; |
2307 | ||
2308 | /* Both statements must be assignments whose RHS is a COMPONENT_REF. */ | |
2309 | if (!gimple_assign_single_p (def1) | |
d7fa6ee2 JJ |
2310 | || !gimple_assign_single_p (def2) |
2311 | || gimple_has_volatile_ops (def1) | |
2312 | || gimple_has_volatile_ops (def2)) | |
372a6eb8 BS |
2313 | continue; |
2314 | ||
2315 | ref1 = gimple_assign_rhs1 (def1); | |
2316 | ref2 = gimple_assign_rhs1 (def2); | |
2317 | ||
2318 | if (TREE_CODE (ref1) != COMPONENT_REF | |
2319 | || TREE_CODE (ref2) != COMPONENT_REF) | |
2320 | continue; | |
2321 | ||
2322 | /* The zeroth operand of the two component references must be | |
2323 | identical. It is not sufficient to compare get_base_address of | |
2324 | the two references, because this could allow for different | |
2325 | elements of the same array in the two trees. It is not safe to | |
2326 | assume that the existence of one array element implies the | |
2327 | existence of a different one. */ | |
2328 | if (!operand_equal_p (TREE_OPERAND (ref1, 0), TREE_OPERAND (ref2, 0), 0)) | |
2329 | continue; | |
2330 | ||
2331 | field1 = TREE_OPERAND (ref1, 1); | |
2332 | field2 = TREE_OPERAND (ref2, 1); | |
2333 | ||
2334 | /* Check for field adjacency, and ensure field1 comes first. */ | |
2335 | for (next = DECL_CHAIN (field1); | |
2336 | next && TREE_CODE (next) != FIELD_DECL; | |
2337 | next = DECL_CHAIN (next)) | |
2338 | ; | |
2339 | ||
2340 | if (next != field2) | |
2341 | { | |
2342 | for (next = DECL_CHAIN (field2); | |
2343 | next && TREE_CODE (next) != FIELD_DECL; | |
2344 | next = DECL_CHAIN (next)) | |
2345 | ; | |
2346 | ||
2347 | if (next != field1) | |
2348 | continue; | |
2349 | ||
fab27f52 MM |
2350 | std::swap (field1, field2); |
2351 | std::swap (def1, def2); | |
372a6eb8 BS |
2352 | } |
2353 | ||
9b10be32 BS |
2354 | bb_for_def1 = gimple_bb (def1); |
2355 | bb_for_def2 = gimple_bb (def2); | |
2356 | ||
372a6eb8 BS |
2357 | /* Check for proper alignment of the first field. */ |
2358 | tree_offset1 = bit_position (field1); | |
2359 | tree_offset2 = bit_position (field2); | |
2360 | tree_size2 = DECL_SIZE (field2); | |
2361 | ||
cc269bb6 RS |
2362 | if (!tree_fits_uhwi_p (tree_offset1) |
2363 | || !tree_fits_uhwi_p (tree_offset2) | |
2364 | || !tree_fits_uhwi_p (tree_size2)) | |
372a6eb8 BS |
2365 | continue; |
2366 | ||
eb1ce453 KZ |
2367 | offset1 = tree_to_uhwi (tree_offset1); |
2368 | offset2 = tree_to_uhwi (tree_offset2); | |
2369 | size2 = tree_to_uhwi (tree_size2); | |
372a6eb8 BS |
2370 | align1 = DECL_ALIGN (field1) % param_align_bits; |
2371 | ||
2372 | if (offset1 % BITS_PER_UNIT != 0) | |
2373 | continue; | |
2374 | ||
2375 | /* For profitability, the two field references should fit within | |
2376 | a single cache line. */ | |
2377 | if (align1 + offset2 - offset1 + size2 > param_align_bits) | |
2378 | continue; | |
2379 | ||
2380 | /* The two expressions cannot be dependent upon vdefs defined | |
2381 | in bb1/bb2. */ | |
2382 | if (local_mem_dependence (def1, bb_for_def1) | |
2383 | || local_mem_dependence (def2, bb_for_def2)) | |
2384 | continue; | |
2385 | ||
2386 | /* The conditions are satisfied; hoist the loads from bb1 and bb2 into | |
2387 | bb0. We hoist the first one first so that a cache miss is handled | |
2388 | efficiently regardless of hardware cache-fill policy. */ | |
2389 | gsi2 = gsi_for_stmt (def1); | |
2390 | gsi_move_to_bb_end (&gsi2, bb0); | |
2391 | gsi2 = gsi_for_stmt (def2); | |
2392 | gsi_move_to_bb_end (&gsi2, bb0); | |
2393 | ||
2394 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2395 | { | |
2396 | fprintf (dump_file, | |
2397 | "\nHoisting adjacent loads from %d and %d into %d: \n", | |
2398 | bb_for_def1->index, bb_for_def2->index, bb0->index); | |
2399 | print_gimple_stmt (dump_file, def1, 0, TDF_VOPS|TDF_MEMSYMS); | |
2400 | print_gimple_stmt (dump_file, def2, 0, TDF_VOPS|TDF_MEMSYMS); | |
2401 | } | |
2402 | } | |
2403 | } | |
2404 | ||
2405 | /* Determine whether we should attempt to hoist adjacent loads out of | |
2406 | diamond patterns in pass_phiopt. Always hoist loads if | |
2407 | -fhoist-adjacent-loads is specified and the target machine has | |
7ef58a1a | 2408 | both a conditional move instruction and a defined cache line size. */ |
372a6eb8 BS |
2409 | |
2410 | static bool | |
2411 | gate_hoist_loads (void) | |
2412 | { | |
7ef58a1a BS |
2413 | return (flag_hoist_adjacent_loads == 1 |
2414 | && PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE) | |
2415 | && HAVE_conditional_move); | |
372a6eb8 BS |
2416 | } |
2417 | ||
be55bfe6 TS |
2418 | /* This pass tries to replaces an if-then-else block with an |
2419 | assignment. We have four kinds of transformations. Some of these | |
2420 | transformations are also performed by the ifcvt RTL optimizer. | |
2421 | ||
2422 | Conditional Replacement | |
2423 | ----------------------- | |
2424 | ||
2425 | This transformation, implemented in conditional_replacement, | |
2426 | replaces | |
2427 | ||
2428 | bb0: | |
2429 | if (cond) goto bb2; else goto bb1; | |
2430 | bb1: | |
2431 | bb2: | |
2432 | x = PHI <0 (bb1), 1 (bb0), ...>; | |
2433 | ||
2434 | with | |
2435 | ||
2436 | bb0: | |
2437 | x' = cond; | |
2438 | goto bb2; | |
2439 | bb2: | |
2440 | x = PHI <x' (bb0), ...>; | |
2441 | ||
2442 | We remove bb1 as it becomes unreachable. This occurs often due to | |
2443 | gimplification of conditionals. | |
2444 | ||
2445 | Value Replacement | |
2446 | ----------------- | |
2447 | ||
2448 | This transformation, implemented in value_replacement, replaces | |
2449 | ||
2450 | bb0: | |
2451 | if (a != b) goto bb2; else goto bb1; | |
2452 | bb1: | |
2453 | bb2: | |
2454 | x = PHI <a (bb1), b (bb0), ...>; | |
2455 | ||
2456 | with | |
2457 | ||
2458 | bb0: | |
2459 | bb2: | |
2460 | x = PHI <b (bb0), ...>; | |
2461 | ||
2462 | This opportunity can sometimes occur as a result of other | |
2463 | optimizations. | |
2464 | ||
2465 | ||
2466 | Another case caught by value replacement looks like this: | |
2467 | ||
2468 | bb0: | |
2469 | t1 = a == CONST; | |
2470 | t2 = b > c; | |
2471 | t3 = t1 & t2; | |
2472 | if (t3 != 0) goto bb1; else goto bb2; | |
2473 | bb1: | |
2474 | bb2: | |
2475 | x = PHI (CONST, a) | |
2476 | ||
2477 | Gets replaced with: | |
2478 | bb0: | |
2479 | bb2: | |
2480 | t1 = a == CONST; | |
2481 | t2 = b > c; | |
2482 | t3 = t1 & t2; | |
2483 | x = a; | |
2484 | ||
2485 | ABS Replacement | |
2486 | --------------- | |
2487 | ||
2488 | This transformation, implemented in abs_replacement, replaces | |
2489 | ||
2490 | bb0: | |
2491 | if (a >= 0) goto bb2; else goto bb1; | |
2492 | bb1: | |
2493 | x = -a; | |
2494 | bb2: | |
2495 | x = PHI <x (bb1), a (bb0), ...>; | |
2496 | ||
2497 | with | |
2498 | ||
2499 | bb0: | |
2500 | x' = ABS_EXPR< a >; | |
2501 | bb2: | |
2502 | x = PHI <x' (bb0), ...>; | |
2503 | ||
2504 | MIN/MAX Replacement | |
2505 | ------------------- | |
2506 | ||
2507 | This transformation, minmax_replacement replaces | |
2508 | ||
2509 | bb0: | |
2510 | if (a <= b) goto bb2; else goto bb1; | |
2511 | bb1: | |
2512 | bb2: | |
2513 | x = PHI <b (bb1), a (bb0), ...>; | |
2514 | ||
2515 | with | |
2516 | ||
2517 | bb0: | |
2518 | x' = MIN_EXPR (a, b) | |
2519 | bb2: | |
2520 | x = PHI <x' (bb0), ...>; | |
2521 | ||
2522 | A similar transformation is done for MAX_EXPR. | |
2523 | ||
2524 | ||
2525 | This pass also performs a fifth transformation of a slightly different | |
2526 | flavor. | |
2527 | ||
98441735 KV |
2528 | Factor conversion in COND_EXPR |
2529 | ------------------------------ | |
2530 | ||
2531 | This transformation factors the conversion out of COND_EXPR with | |
2532 | factor_out_conditional_conversion. | |
2533 | ||
2534 | For example: | |
2535 | if (a <= CST) goto <bb 3>; else goto <bb 4>; | |
2536 | <bb 3>: | |
2537 | tmp = (int) a; | |
2538 | <bb 4>: | |
2539 | tmp = PHI <tmp, CST> | |
2540 | ||
2541 | Into: | |
2542 | if (a <= CST) goto <bb 3>; else goto <bb 4>; | |
2543 | <bb 3>: | |
2544 | <bb 4>: | |
2545 | a = PHI <a, CST> | |
2546 | tmp = (int) a; | |
2547 | ||
be55bfe6 TS |
2548 | Adjacent Load Hoisting |
2549 | ---------------------- | |
2550 | ||
2551 | This transformation replaces | |
2552 | ||
2553 | bb0: | |
2554 | if (...) goto bb2; else goto bb1; | |
2555 | bb1: | |
2556 | x1 = (<expr>).field1; | |
2557 | goto bb3; | |
2558 | bb2: | |
2559 | x2 = (<expr>).field2; | |
2560 | bb3: | |
2561 | # x = PHI <x1, x2>; | |
2562 | ||
2563 | with | |
2564 | ||
2565 | bb0: | |
2566 | x1 = (<expr>).field1; | |
2567 | x2 = (<expr>).field2; | |
2568 | if (...) goto bb2; else goto bb1; | |
2569 | bb1: | |
2570 | goto bb3; | |
2571 | bb2: | |
2572 | bb3: | |
2573 | # x = PHI <x1, x2>; | |
2574 | ||
2575 | The purpose of this transformation is to enable generation of conditional | |
2576 | move instructions such as Intel CMOVE or PowerPC ISEL. Because one of | |
2577 | the loads is speculative, the transformation is restricted to very | |
2578 | specific cases to avoid introducing a page fault. We are looking for | |
2579 | the common idiom: | |
2580 | ||
2581 | if (...) | |
2582 | x = y->left; | |
2583 | else | |
2584 | x = y->right; | |
2585 | ||
2586 | where left and right are typically adjacent pointers in a tree structure. */ | |
0385f644 | 2587 | |
27a4cd48 DM |
2588 | namespace { |
2589 | ||
2590 | const pass_data pass_data_phiopt = | |
6de9cd9a | 2591 | { |
27a4cd48 DM |
2592 | GIMPLE_PASS, /* type */ |
2593 | "phiopt", /* name */ | |
2594 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
2595 | TV_TREE_PHIOPT, /* tv_id */ |
2596 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2597 | 0, /* properties_provided */ | |
2598 | 0, /* properties_destroyed */ | |
2599 | 0, /* todo_flags_start */ | |
3bea341f | 2600 | 0, /* todo_flags_finish */ |
6de9cd9a | 2601 | }; |
a5828d1e | 2602 | |
27a4cd48 DM |
2603 | class pass_phiopt : public gimple_opt_pass |
2604 | { | |
2605 | public: | |
c3284718 RS |
2606 | pass_phiopt (gcc::context *ctxt) |
2607 | : gimple_opt_pass (pass_data_phiopt, ctxt) | |
27a4cd48 DM |
2608 | {} |
2609 | ||
2610 | /* opt_pass methods: */ | |
65d3284b | 2611 | opt_pass * clone () { return new pass_phiopt (m_ctxt); } |
68f6df73 | 2612 | virtual bool gate (function *) { return flag_ssa_phiopt; } |
be55bfe6 TS |
2613 | virtual unsigned int execute (function *) |
2614 | { | |
2615 | return tree_ssa_phiopt_worker (false, gate_hoist_loads ()); | |
2616 | } | |
27a4cd48 DM |
2617 | |
2618 | }; // class pass_phiopt | |
2619 | ||
2620 | } // anon namespace | |
2621 | ||
2622 | gimple_opt_pass * | |
2623 | make_pass_phiopt (gcc::context *ctxt) | |
2624 | { | |
2625 | return new pass_phiopt (ctxt); | |
2626 | } | |
2627 | ||
27a4cd48 DM |
2628 | namespace { |
2629 | ||
2630 | const pass_data pass_data_cselim = | |
a5828d1e | 2631 | { |
27a4cd48 DM |
2632 | GIMPLE_PASS, /* type */ |
2633 | "cselim", /* name */ | |
2634 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
2635 | TV_TREE_PHIOPT, /* tv_id */ |
2636 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2637 | 0, /* properties_provided */ | |
2638 | 0, /* properties_destroyed */ | |
2639 | 0, /* todo_flags_start */ | |
3bea341f | 2640 | 0, /* todo_flags_finish */ |
a5828d1e | 2641 | }; |
27a4cd48 DM |
2642 | |
2643 | class pass_cselim : public gimple_opt_pass | |
2644 | { | |
2645 | public: | |
c3284718 RS |
2646 | pass_cselim (gcc::context *ctxt) |
2647 | : gimple_opt_pass (pass_data_cselim, ctxt) | |
27a4cd48 DM |
2648 | {} |
2649 | ||
2650 | /* opt_pass methods: */ | |
1a3d085c | 2651 | virtual bool gate (function *) { return flag_tree_cselim; } |
be55bfe6 | 2652 | virtual unsigned int execute (function *) { return tree_ssa_cs_elim (); } |
27a4cd48 DM |
2653 | |
2654 | }; // class pass_cselim | |
2655 | ||
2656 | } // anon namespace | |
2657 | ||
2658 | gimple_opt_pass * | |
2659 | make_pass_cselim (gcc::context *ctxt) | |
2660 | { | |
2661 | return new pass_cselim (ctxt); | |
2662 | } |