]>
Commit | Line | Data |
---|---|---|
291d763b | 1 | /* Forward propagation of expressions for single use variables. |
51dbf409 | 2 | Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010, 2011, 2012 |
ce084dfc | 3 | Free Software Foundation, Inc. |
4ee9c684 | 4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
8c4c00c1 | 9 | the Free Software Foundation; either version 3, or (at your option) |
4ee9c684 | 10 | any later version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 20 | |
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
4ee9c684 | 25 | #include "tree.h" |
4ee9c684 | 26 | #include "tm_p.h" |
27 | #include "basic-block.h" | |
28 | #include "timevar.h" | |
e5b1e080 | 29 | #include "gimple-pretty-print.h" |
4ee9c684 | 30 | #include "tree-flow.h" |
31 | #include "tree-pass.h" | |
32 | #include "tree-dump.h" | |
291d763b | 33 | #include "langhooks.h" |
5adc1066 | 34 | #include "flags.h" |
75a70cf9 | 35 | #include "gimple.h" |
27f931ff | 36 | #include "expr.h" |
4ee9c684 | 37 | |
291d763b | 38 | /* This pass propagates the RHS of assignment statements into use |
39 | sites of the LHS of the assignment. It's basically a specialized | |
8f628ee8 | 40 | form of tree combination. It is hoped all of this can disappear |
41 | when we have a generalized tree combiner. | |
4ee9c684 | 42 | |
291d763b | 43 | One class of common cases we handle is forward propagating a single use |
48e1416a | 44 | variable into a COND_EXPR. |
4ee9c684 | 45 | |
46 | bb0: | |
47 | x = a COND b; | |
48 | if (x) goto ... else goto ... | |
49 | ||
50 | Will be transformed into: | |
51 | ||
52 | bb0: | |
53 | if (a COND b) goto ... else goto ... | |
48e1416a | 54 | |
4ee9c684 | 55 | Similarly for the tests (x == 0), (x != 0), (x == 1) and (x != 1). |
56 | ||
57 | Or (assuming c1 and c2 are constants): | |
58 | ||
59 | bb0: | |
48e1416a | 60 | x = a + c1; |
4ee9c684 | 61 | if (x EQ/NEQ c2) goto ... else goto ... |
62 | ||
63 | Will be transformed into: | |
64 | ||
65 | bb0: | |
66 | if (a EQ/NEQ (c2 - c1)) goto ... else goto ... | |
67 | ||
68 | Similarly for x = a - c1. | |
48e1416a | 69 | |
4ee9c684 | 70 | Or |
71 | ||
72 | bb0: | |
73 | x = !a | |
74 | if (x) goto ... else goto ... | |
75 | ||
76 | Will be transformed into: | |
77 | ||
78 | bb0: | |
79 | if (a == 0) goto ... else goto ... | |
80 | ||
81 | Similarly for the tests (x == 0), (x != 0), (x == 1) and (x != 1). | |
82 | For these cases, we propagate A into all, possibly more than one, | |
83 | COND_EXPRs that use X. | |
84 | ||
f5c8cff5 | 85 | Or |
86 | ||
87 | bb0: | |
88 | x = (typecast) a | |
89 | if (x) goto ... else goto ... | |
90 | ||
91 | Will be transformed into: | |
92 | ||
93 | bb0: | |
94 | if (a != 0) goto ... else goto ... | |
95 | ||
96 | (Assuming a is an integral type and x is a boolean or x is an | |
97 | integral and a is a boolean.) | |
98 | ||
99 | Similarly for the tests (x == 0), (x != 0), (x == 1) and (x != 1). | |
100 | For these cases, we propagate A into all, possibly more than one, | |
101 | COND_EXPRs that use X. | |
102 | ||
4ee9c684 | 103 | In addition to eliminating the variable and the statement which assigns |
104 | a value to the variable, we may be able to later thread the jump without | |
e6dfde59 | 105 | adding insane complexity in the dominator optimizer. |
4ee9c684 | 106 | |
f5c8cff5 | 107 | Also note these transformations can cascade. We handle this by having |
108 | a worklist of COND_EXPR statements to examine. As we make a change to | |
109 | a statement, we put it back on the worklist to examine on the next | |
110 | iteration of the main loop. | |
111 | ||
291d763b | 112 | A second class of propagation opportunities arises for ADDR_EXPR |
113 | nodes. | |
114 | ||
115 | ptr = &x->y->z; | |
116 | res = *ptr; | |
117 | ||
118 | Will get turned into | |
119 | ||
120 | res = x->y->z; | |
121 | ||
50f39ec6 | 122 | Or |
123 | ptr = (type1*)&type2var; | |
124 | res = *ptr | |
125 | ||
126 | Will get turned into (if type1 and type2 are the same size | |
127 | and neither have volatile on them): | |
128 | res = VIEW_CONVERT_EXPR<type1>(type2var) | |
129 | ||
291d763b | 130 | Or |
131 | ||
132 | ptr = &x[0]; | |
133 | ptr2 = ptr + <constant>; | |
134 | ||
135 | Will get turned into | |
136 | ||
137 | ptr2 = &x[constant/elementsize]; | |
138 | ||
139 | Or | |
140 | ||
141 | ptr = &x[0]; | |
142 | offset = index * element_size; | |
143 | offset_p = (pointer) offset; | |
144 | ptr2 = ptr + offset_p | |
145 | ||
146 | Will get turned into: | |
147 | ||
148 | ptr2 = &x[index]; | |
149 | ||
1c4607fd | 150 | Or |
151 | ssa = (int) decl | |
152 | res = ssa & 1 | |
153 | ||
154 | Provided that decl has known alignment >= 2, will get turned into | |
155 | ||
156 | res = 0 | |
157 | ||
8f628ee8 | 158 | We also propagate casts into SWITCH_EXPR and COND_EXPR conditions to |
159 | allow us to remove the cast and {NOT_EXPR,NEG_EXPR} into a subsequent | |
160 | {NOT_EXPR,NEG_EXPR}. | |
291d763b | 161 | |
4ee9c684 | 162 | This will (of course) be extended as other needs arise. */ |
163 | ||
15ec875c | 164 | static bool forward_propagate_addr_expr (tree name, tree rhs); |
148aa112 | 165 | |
166 | /* Set to true if we delete EH edges during the optimization. */ | |
167 | static bool cfg_changed; | |
168 | ||
75a70cf9 | 169 | static tree rhs_to_tree (tree type, gimple stmt); |
148aa112 | 170 | |
83a20baf | 171 | /* Get the next statement we can propagate NAME's value into skipping |
5adc1066 | 172 | trivial copies. Returns the statement that is suitable as a |
173 | propagation destination or NULL_TREE if there is no such one. | |
174 | This only returns destinations in a single-use chain. FINAL_NAME_P | |
175 | if non-NULL is written to the ssa name that represents the use. */ | |
a3451973 | 176 | |
75a70cf9 | 177 | static gimple |
5adc1066 | 178 | get_prop_dest_stmt (tree name, tree *final_name_p) |
a3451973 | 179 | { |
5adc1066 | 180 | use_operand_p use; |
75a70cf9 | 181 | gimple use_stmt; |
a3451973 | 182 | |
5adc1066 | 183 | do { |
184 | /* If name has multiple uses, bail out. */ | |
185 | if (!single_imm_use (name, &use, &use_stmt)) | |
75a70cf9 | 186 | return NULL; |
a3451973 | 187 | |
5adc1066 | 188 | /* If this is not a trivial copy, we found it. */ |
8f0b877f | 189 | if (!gimple_assign_ssa_name_copy_p (use_stmt) |
75a70cf9 | 190 | || gimple_assign_rhs1 (use_stmt) != name) |
5adc1066 | 191 | break; |
192 | ||
193 | /* Continue searching uses of the copy destination. */ | |
75a70cf9 | 194 | name = gimple_assign_lhs (use_stmt); |
5adc1066 | 195 | } while (1); |
196 | ||
197 | if (final_name_p) | |
198 | *final_name_p = name; | |
199 | ||
200 | return use_stmt; | |
a3451973 | 201 | } |
202 | ||
5adc1066 | 203 | /* Get the statement we can propagate from into NAME skipping |
204 | trivial copies. Returns the statement which defines the | |
205 | propagation source or NULL_TREE if there is no such one. | |
206 | If SINGLE_USE_ONLY is set considers only sources which have | |
207 | a single use chain up to NAME. If SINGLE_USE_P is non-null, | |
208 | it is set to whether the chain to NAME is a single use chain | |
209 | or not. SINGLE_USE_P is not written to if SINGLE_USE_ONLY is set. */ | |
4ee9c684 | 210 | |
75a70cf9 | 211 | static gimple |
5adc1066 | 212 | get_prop_source_stmt (tree name, bool single_use_only, bool *single_use_p) |
f5c8cff5 | 213 | { |
5adc1066 | 214 | bool single_use = true; |
215 | ||
216 | do { | |
75a70cf9 | 217 | gimple def_stmt = SSA_NAME_DEF_STMT (name); |
5adc1066 | 218 | |
219 | if (!has_single_use (name)) | |
220 | { | |
221 | single_use = false; | |
222 | if (single_use_only) | |
75a70cf9 | 223 | return NULL; |
5adc1066 | 224 | } |
225 | ||
226 | /* If name is defined by a PHI node or is the default def, bail out. */ | |
8f0b877f | 227 | if (!is_gimple_assign (def_stmt)) |
75a70cf9 | 228 | return NULL; |
5adc1066 | 229 | |
8f0b877f | 230 | /* If def_stmt is not a simple copy, we possibly found it. */ |
231 | if (!gimple_assign_ssa_name_copy_p (def_stmt)) | |
5adc1066 | 232 | { |
b9e98b8a | 233 | tree rhs; |
234 | ||
5adc1066 | 235 | if (!single_use_only && single_use_p) |
236 | *single_use_p = single_use; | |
237 | ||
b9e98b8a | 238 | /* We can look through pointer conversions in the search |
239 | for a useful stmt for the comparison folding. */ | |
75a70cf9 | 240 | rhs = gimple_assign_rhs1 (def_stmt); |
d9659041 | 241 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt)) |
75a70cf9 | 242 | && TREE_CODE (rhs) == SSA_NAME |
243 | && POINTER_TYPE_P (TREE_TYPE (gimple_assign_lhs (def_stmt))) | |
244 | && POINTER_TYPE_P (TREE_TYPE (rhs))) | |
245 | name = rhs; | |
b9e98b8a | 246 | else |
247 | return def_stmt; | |
248 | } | |
249 | else | |
250 | { | |
251 | /* Continue searching the def of the copy source name. */ | |
75a70cf9 | 252 | name = gimple_assign_rhs1 (def_stmt); |
5adc1066 | 253 | } |
5adc1066 | 254 | } while (1); |
255 | } | |
e6dfde59 | 256 | |
5adc1066 | 257 | /* Checks if the destination ssa name in DEF_STMT can be used as |
258 | propagation source. Returns true if so, otherwise false. */ | |
e6dfde59 | 259 | |
5adc1066 | 260 | static bool |
75a70cf9 | 261 | can_propagate_from (gimple def_stmt) |
5adc1066 | 262 | { |
75a70cf9 | 263 | gcc_assert (is_gimple_assign (def_stmt)); |
8f0b877f | 264 | |
484b827b | 265 | /* If the rhs has side-effects we cannot propagate from it. */ |
75a70cf9 | 266 | if (gimple_has_volatile_ops (def_stmt)) |
484b827b | 267 | return false; |
268 | ||
269 | /* If the rhs is a load we cannot propagate from it. */ | |
75a70cf9 | 270 | if (TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_reference |
271 | || TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_declaration) | |
484b827b | 272 | return false; |
273 | ||
b9e98b8a | 274 | /* Constants can be always propagated. */ |
8f0b877f | 275 | if (gimple_assign_single_p (def_stmt) |
276 | && is_gimple_min_invariant (gimple_assign_rhs1 (def_stmt))) | |
b9e98b8a | 277 | return true; |
278 | ||
75a70cf9 | 279 | /* We cannot propagate ssa names that occur in abnormal phi nodes. */ |
32cdcc42 | 280 | if (stmt_references_abnormal_ssa_name (def_stmt)) |
281 | return false; | |
4ee9c684 | 282 | |
5adc1066 | 283 | /* If the definition is a conversion of a pointer to a function type, |
75a70cf9 | 284 | then we can not apply optimizations as some targets require |
285 | function pointers to be canonicalized and in this case this | |
286 | optimization could eliminate a necessary canonicalization. */ | |
8f0b877f | 287 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) |
75a70cf9 | 288 | { |
289 | tree rhs = gimple_assign_rhs1 (def_stmt); | |
290 | if (POINTER_TYPE_P (TREE_TYPE (rhs)) | |
291 | && TREE_CODE (TREE_TYPE (TREE_TYPE (rhs))) == FUNCTION_TYPE) | |
292 | return false; | |
293 | } | |
8f0b877f | 294 | |
5adc1066 | 295 | return true; |
e6dfde59 | 296 | } |
297 | ||
ff0739e0 | 298 | /* Remove a chain of dead statements starting at the definition of |
299 | NAME. The chain is linked via the first operand of the defining statements. | |
5d2361b0 | 300 | If NAME was replaced in its only use then this function can be used |
ff0739e0 | 301 | to clean up dead stmts. The function handles already released SSA |
302 | names gracefully. | |
303 | Returns true if cleanup-cfg has to run. */ | |
8f628ee8 | 304 | |
5adc1066 | 305 | static bool |
5d2361b0 | 306 | remove_prop_source_from_use (tree name) |
5adc1066 | 307 | { |
75a70cf9 | 308 | gimple_stmt_iterator gsi; |
309 | gimple stmt; | |
5d2361b0 | 310 | bool cfg_changed = false; |
8f628ee8 | 311 | |
5adc1066 | 312 | do { |
5d2361b0 | 313 | basic_block bb; |
314 | ||
ff0739e0 | 315 | if (SSA_NAME_IN_FREE_LIST (name) |
316 | || SSA_NAME_IS_DEFAULT_DEF (name) | |
317 | || !has_zero_uses (name)) | |
5d2361b0 | 318 | return cfg_changed; |
8f628ee8 | 319 | |
5adc1066 | 320 | stmt = SSA_NAME_DEF_STMT (name); |
ff0739e0 | 321 | if (gimple_code (stmt) == GIMPLE_PHI |
322 | || gimple_has_side_effects (stmt)) | |
6f9714b3 | 323 | return cfg_changed; |
ff0739e0 | 324 | |
325 | bb = gimple_bb (stmt); | |
6f9714b3 | 326 | gsi = gsi_for_stmt (stmt); |
ff0739e0 | 327 | unlink_stmt_vdef (stmt); |
13ff78a4 | 328 | if (gsi_remove (&gsi, true)) |
329 | cfg_changed |= gimple_purge_dead_eh_edges (bb); | |
ff0739e0 | 330 | release_defs (stmt); |
8f628ee8 | 331 | |
ff0739e0 | 332 | name = is_gimple_assign (stmt) ? gimple_assign_rhs1 (stmt) : NULL_TREE; |
75a70cf9 | 333 | } while (name && TREE_CODE (name) == SSA_NAME); |
8f628ee8 | 334 | |
5d2361b0 | 335 | return cfg_changed; |
5adc1066 | 336 | } |
8f628ee8 | 337 | |
75a70cf9 | 338 | /* Return the rhs of a gimple_assign STMT in a form of a single tree, |
339 | converted to type TYPE. | |
48e1416a | 340 | |
75a70cf9 | 341 | This should disappear, but is needed so we can combine expressions and use |
342 | the fold() interfaces. Long term, we need to develop folding and combine | |
343 | routines that deal with gimple exclusively . */ | |
344 | ||
345 | static tree | |
346 | rhs_to_tree (tree type, gimple stmt) | |
347 | { | |
389dd41b | 348 | location_t loc = gimple_location (stmt); |
75a70cf9 | 349 | enum tree_code code = gimple_assign_rhs_code (stmt); |
57c45d70 | 350 | if (get_gimple_rhs_class (code) == GIMPLE_TERNARY_RHS) |
351 | return fold_build3_loc (loc, code, type, gimple_assign_rhs1 (stmt), | |
352 | gimple_assign_rhs2 (stmt), | |
353 | gimple_assign_rhs3 (stmt)); | |
354 | else if (get_gimple_rhs_class (code) == GIMPLE_BINARY_RHS) | |
389dd41b | 355 | return fold_build2_loc (loc, code, type, gimple_assign_rhs1 (stmt), |
fb8ed03f | 356 | gimple_assign_rhs2 (stmt)); |
75a70cf9 | 357 | else if (get_gimple_rhs_class (code) == GIMPLE_UNARY_RHS) |
fb8ed03f | 358 | return build1 (code, type, gimple_assign_rhs1 (stmt)); |
75a70cf9 | 359 | else if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS) |
360 | return gimple_assign_rhs1 (stmt); | |
361 | else | |
362 | gcc_unreachable (); | |
363 | } | |
364 | ||
5adc1066 | 365 | /* Combine OP0 CODE OP1 in the context of a COND_EXPR. Returns |
366 | the folded result in a form suitable for COND_EXPR_COND or | |
367 | NULL_TREE, if there is no suitable simplified form. If | |
368 | INVARIANT_ONLY is true only gimple_min_invariant results are | |
369 | considered simplified. */ | |
8f628ee8 | 370 | |
371 | static tree | |
c73fee76 | 372 | combine_cond_expr_cond (gimple stmt, enum tree_code code, tree type, |
5adc1066 | 373 | tree op0, tree op1, bool invariant_only) |
8f628ee8 | 374 | { |
5adc1066 | 375 | tree t; |
8f628ee8 | 376 | |
5adc1066 | 377 | gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison); |
8f628ee8 | 378 | |
c73fee76 | 379 | fold_defer_overflow_warnings (); |
380 | t = fold_binary_loc (gimple_location (stmt), code, type, op0, op1); | |
5adc1066 | 381 | if (!t) |
c73fee76 | 382 | { |
383 | fold_undefer_overflow_warnings (false, NULL, 0); | |
384 | return NULL_TREE; | |
385 | } | |
8f628ee8 | 386 | |
5adc1066 | 387 | /* Require that we got a boolean type out if we put one in. */ |
388 | gcc_assert (TREE_CODE (TREE_TYPE (t)) == TREE_CODE (type)); | |
8f628ee8 | 389 | |
a7392604 | 390 | /* Canonicalize the combined condition for use in a COND_EXPR. */ |
391 | t = canonicalize_cond_expr_cond (t); | |
8f628ee8 | 392 | |
5adc1066 | 393 | /* Bail out if we required an invariant but didn't get one. */ |
75a70cf9 | 394 | if (!t || (invariant_only && !is_gimple_min_invariant (t))) |
c73fee76 | 395 | { |
396 | fold_undefer_overflow_warnings (false, NULL, 0); | |
397 | return NULL_TREE; | |
398 | } | |
399 | ||
400 | fold_undefer_overflow_warnings (!gimple_no_warning_p (stmt), stmt, 0); | |
8f628ee8 | 401 | |
a7392604 | 402 | return t; |
8f628ee8 | 403 | } |
404 | ||
c8126d25 | 405 | /* Combine the comparison OP0 CODE OP1 at LOC with the defining statements |
406 | of its operand. Return a new comparison tree or NULL_TREE if there | |
407 | were no simplifying combines. */ | |
408 | ||
409 | static tree | |
c73fee76 | 410 | forward_propagate_into_comparison_1 (gimple stmt, |
678b2f5b | 411 | enum tree_code code, tree type, |
412 | tree op0, tree op1) | |
c8126d25 | 413 | { |
414 | tree tmp = NULL_TREE; | |
415 | tree rhs0 = NULL_TREE, rhs1 = NULL_TREE; | |
416 | bool single_use0_p = false, single_use1_p = false; | |
417 | ||
418 | /* For comparisons use the first operand, that is likely to | |
419 | simplify comparisons against constants. */ | |
420 | if (TREE_CODE (op0) == SSA_NAME) | |
421 | { | |
422 | gimple def_stmt = get_prop_source_stmt (op0, false, &single_use0_p); | |
423 | if (def_stmt && can_propagate_from (def_stmt)) | |
424 | { | |
425 | rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt); | |
c73fee76 | 426 | tmp = combine_cond_expr_cond (stmt, code, type, |
c8126d25 | 427 | rhs0, op1, !single_use0_p); |
428 | if (tmp) | |
429 | return tmp; | |
430 | } | |
431 | } | |
432 | ||
433 | /* If that wasn't successful, try the second operand. */ | |
434 | if (TREE_CODE (op1) == SSA_NAME) | |
435 | { | |
436 | gimple def_stmt = get_prop_source_stmt (op1, false, &single_use1_p); | |
437 | if (def_stmt && can_propagate_from (def_stmt)) | |
438 | { | |
439 | rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt); | |
c73fee76 | 440 | tmp = combine_cond_expr_cond (stmt, code, type, |
c8126d25 | 441 | op0, rhs1, !single_use1_p); |
442 | if (tmp) | |
443 | return tmp; | |
444 | } | |
445 | } | |
446 | ||
447 | /* If that wasn't successful either, try both operands. */ | |
448 | if (rhs0 != NULL_TREE | |
449 | && rhs1 != NULL_TREE) | |
c73fee76 | 450 | tmp = combine_cond_expr_cond (stmt, code, type, |
c8126d25 | 451 | rhs0, rhs1, |
452 | !(single_use0_p && single_use1_p)); | |
453 | ||
454 | return tmp; | |
455 | } | |
456 | ||
678b2f5b | 457 | /* Propagate from the ssa name definition statements of the assignment |
458 | from a comparison at *GSI into the conditional if that simplifies it. | |
6f9714b3 | 459 | Returns 1 if the stmt was modified and 2 if the CFG needs cleanup, |
460 | otherwise returns 0. */ | |
c8126d25 | 461 | |
6f9714b3 | 462 | static int |
678b2f5b | 463 | forward_propagate_into_comparison (gimple_stmt_iterator *gsi) |
c8126d25 | 464 | { |
678b2f5b | 465 | gimple stmt = gsi_stmt (*gsi); |
466 | tree tmp; | |
6f9714b3 | 467 | bool cfg_changed = false; |
56632de0 | 468 | tree type = TREE_TYPE (gimple_assign_lhs (stmt)); |
6f9714b3 | 469 | tree rhs1 = gimple_assign_rhs1 (stmt); |
470 | tree rhs2 = gimple_assign_rhs2 (stmt); | |
c8126d25 | 471 | |
472 | /* Combine the comparison with defining statements. */ | |
c73fee76 | 473 | tmp = forward_propagate_into_comparison_1 (stmt, |
678b2f5b | 474 | gimple_assign_rhs_code (stmt), |
56632de0 | 475 | type, rhs1, rhs2); |
476 | if (tmp && useless_type_conversion_p (type, TREE_TYPE (tmp))) | |
c8126d25 | 477 | { |
678b2f5b | 478 | gimple_assign_set_rhs_from_tree (gsi, tmp); |
50aacf4c | 479 | fold_stmt (gsi); |
480 | update_stmt (gsi_stmt (*gsi)); | |
75200312 | 481 | |
6f9714b3 | 482 | if (TREE_CODE (rhs1) == SSA_NAME) |
483 | cfg_changed |= remove_prop_source_from_use (rhs1); | |
484 | if (TREE_CODE (rhs2) == SSA_NAME) | |
485 | cfg_changed |= remove_prop_source_from_use (rhs2); | |
486 | return cfg_changed ? 2 : 1; | |
c8126d25 | 487 | } |
488 | ||
6f9714b3 | 489 | return 0; |
c8126d25 | 490 | } |
491 | ||
5adc1066 | 492 | /* Propagate from the ssa name definition statements of COND_EXPR |
75a70cf9 | 493 | in GIMPLE_COND statement STMT into the conditional if that simplifies it. |
494 | Returns zero if no statement was changed, one if there were | |
495 | changes and two if cfg_cleanup needs to run. | |
48e1416a | 496 | |
75a70cf9 | 497 | This must be kept in sync with forward_propagate_into_cond. */ |
498 | ||
499 | static int | |
500 | forward_propagate_into_gimple_cond (gimple stmt) | |
501 | { | |
678b2f5b | 502 | tree tmp; |
503 | enum tree_code code = gimple_cond_code (stmt); | |
6f9714b3 | 504 | bool cfg_changed = false; |
505 | tree rhs1 = gimple_cond_lhs (stmt); | |
506 | tree rhs2 = gimple_cond_rhs (stmt); | |
678b2f5b | 507 | |
508 | /* We can do tree combining on SSA_NAME and comparison expressions. */ | |
509 | if (TREE_CODE_CLASS (gimple_cond_code (stmt)) != tcc_comparison) | |
510 | return 0; | |
511 | ||
c73fee76 | 512 | tmp = forward_propagate_into_comparison_1 (stmt, code, |
678b2f5b | 513 | boolean_type_node, |
6f9714b3 | 514 | rhs1, rhs2); |
678b2f5b | 515 | if (tmp) |
516 | { | |
517 | if (dump_file && tmp) | |
518 | { | |
678b2f5b | 519 | fprintf (dump_file, " Replaced '"); |
6f9714b3 | 520 | print_gimple_expr (dump_file, stmt, 0, 0); |
678b2f5b | 521 | fprintf (dump_file, "' with '"); |
522 | print_generic_expr (dump_file, tmp, 0); | |
523 | fprintf (dump_file, "'\n"); | |
524 | } | |
75a70cf9 | 525 | |
678b2f5b | 526 | gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp)); |
527 | update_stmt (stmt); | |
75a70cf9 | 528 | |
6f9714b3 | 529 | if (TREE_CODE (rhs1) == SSA_NAME) |
530 | cfg_changed |= remove_prop_source_from_use (rhs1); | |
531 | if (TREE_CODE (rhs2) == SSA_NAME) | |
532 | cfg_changed |= remove_prop_source_from_use (rhs2); | |
533 | return (cfg_changed || is_gimple_min_invariant (tmp)) ? 2 : 1; | |
678b2f5b | 534 | } |
75a70cf9 | 535 | |
10a6edd6 | 536 | /* Canonicalize _Bool == 0 and _Bool != 1 to _Bool != 0 by swapping edges. */ |
537 | if ((TREE_CODE (TREE_TYPE (rhs1)) == BOOLEAN_TYPE | |
538 | || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
539 | && TYPE_PRECISION (TREE_TYPE (rhs1)) == 1)) | |
540 | && ((code == EQ_EXPR | |
541 | && integer_zerop (rhs2)) | |
542 | || (code == NE_EXPR | |
543 | && integer_onep (rhs2)))) | |
544 | { | |
545 | basic_block bb = gimple_bb (stmt); | |
546 | gimple_cond_set_code (stmt, NE_EXPR); | |
547 | gimple_cond_set_rhs (stmt, build_zero_cst (TREE_TYPE (rhs1))); | |
548 | EDGE_SUCC (bb, 0)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE); | |
549 | EDGE_SUCC (bb, 1)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE); | |
550 | return 1; | |
551 | } | |
552 | ||
6f9714b3 | 553 | return 0; |
75a70cf9 | 554 | } |
555 | ||
556 | ||
557 | /* Propagate from the ssa name definition statements of COND_EXPR | |
558 | in the rhs of statement STMT into the conditional if that simplifies it. | |
8a2caf10 | 559 | Returns true zero if the stmt was changed. */ |
4ee9c684 | 560 | |
8a2caf10 | 561 | static bool |
75a70cf9 | 562 | forward_propagate_into_cond (gimple_stmt_iterator *gsi_p) |
e6dfde59 | 563 | { |
75a70cf9 | 564 | gimple stmt = gsi_stmt (*gsi_p); |
678b2f5b | 565 | tree tmp = NULL_TREE; |
566 | tree cond = gimple_assign_rhs1 (stmt); | |
10a6edd6 | 567 | bool swap = false; |
d080be9e | 568 | |
678b2f5b | 569 | /* We can do tree combining on SSA_NAME and comparison expressions. */ |
570 | if (COMPARISON_CLASS_P (cond)) | |
c73fee76 | 571 | tmp = forward_propagate_into_comparison_1 (stmt, TREE_CODE (cond), |
c8126d25 | 572 | boolean_type_node, |
573 | TREE_OPERAND (cond, 0), | |
574 | TREE_OPERAND (cond, 1)); | |
678b2f5b | 575 | else if (TREE_CODE (cond) == SSA_NAME) |
576 | { | |
10a6edd6 | 577 | enum tree_code code; |
8a2caf10 | 578 | tree name = cond; |
678b2f5b | 579 | gimple def_stmt = get_prop_source_stmt (name, true, NULL); |
580 | if (!def_stmt || !can_propagate_from (def_stmt)) | |
6f9714b3 | 581 | return 0; |
5adc1066 | 582 | |
10a6edd6 | 583 | code = gimple_assign_rhs_code (def_stmt); |
584 | if (TREE_CODE_CLASS (code) == tcc_comparison) | |
8a2caf10 | 585 | tmp = fold_build2_loc (gimple_location (def_stmt), |
10a6edd6 | 586 | code, |
8a2caf10 | 587 | boolean_type_node, |
588 | gimple_assign_rhs1 (def_stmt), | |
589 | gimple_assign_rhs2 (def_stmt)); | |
10a6edd6 | 590 | else if ((code == BIT_NOT_EXPR |
591 | && TYPE_PRECISION (TREE_TYPE (cond)) == 1) | |
592 | || (code == BIT_XOR_EXPR | |
593 | && integer_onep (gimple_assign_rhs2 (def_stmt)))) | |
594 | { | |
595 | tmp = gimple_assign_rhs1 (def_stmt); | |
596 | swap = true; | |
597 | } | |
678b2f5b | 598 | } |
5adc1066 | 599 | |
25f48be0 | 600 | if (tmp |
601 | && is_gimple_condexpr (tmp)) | |
678b2f5b | 602 | { |
603 | if (dump_file && tmp) | |
604 | { | |
605 | fprintf (dump_file, " Replaced '"); | |
606 | print_generic_expr (dump_file, cond, 0); | |
607 | fprintf (dump_file, "' with '"); | |
608 | print_generic_expr (dump_file, tmp, 0); | |
609 | fprintf (dump_file, "'\n"); | |
610 | } | |
d080be9e | 611 | |
8a2caf10 | 612 | if (integer_onep (tmp)) |
613 | gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs2 (stmt)); | |
614 | else if (integer_zerop (tmp)) | |
615 | gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs3 (stmt)); | |
616 | else | |
10a6edd6 | 617 | { |
618 | gimple_assign_set_rhs1 (stmt, unshare_expr (tmp)); | |
619 | if (swap) | |
620 | { | |
621 | tree t = gimple_assign_rhs2 (stmt); | |
622 | gimple_assign_set_rhs2 (stmt, gimple_assign_rhs3 (stmt)); | |
623 | gimple_assign_set_rhs3 (stmt, t); | |
624 | } | |
625 | } | |
678b2f5b | 626 | stmt = gsi_stmt (*gsi_p); |
627 | update_stmt (stmt); | |
5adc1066 | 628 | |
8a2caf10 | 629 | return true; |
678b2f5b | 630 | } |
d080be9e | 631 | |
6f9714b3 | 632 | return 0; |
4ee9c684 | 633 | } |
634 | ||
360b78f3 | 635 | /* Propagate from the ssa name definition statements of COND_EXPR |
636 | values in the rhs of statement STMT into the conditional arms | |
637 | if that simplifies it. | |
638 | Returns true if the stmt was changed. */ | |
639 | ||
640 | static bool | |
641 | combine_cond_exprs (gimple_stmt_iterator *gsi_p) | |
642 | { | |
643 | gimple stmt = gsi_stmt (*gsi_p); | |
644 | tree cond, val1, val2; | |
645 | bool changed = false; | |
646 | ||
647 | cond = gimple_assign_rhs1 (stmt); | |
648 | val1 = gimple_assign_rhs2 (stmt); | |
649 | if (TREE_CODE (val1) == SSA_NAME) | |
650 | { | |
651 | gimple def_stmt = SSA_NAME_DEF_STMT (val1); | |
652 | if (is_gimple_assign (def_stmt) | |
653 | && gimple_assign_rhs_code (def_stmt) == gimple_assign_rhs_code (stmt) | |
654 | && operand_equal_p (gimple_assign_rhs1 (def_stmt), cond, 0)) | |
655 | { | |
656 | val1 = unshare_expr (gimple_assign_rhs2 (def_stmt)); | |
657 | gimple_assign_set_rhs2 (stmt, val1); | |
658 | changed = true; | |
659 | } | |
660 | } | |
661 | val2 = gimple_assign_rhs3 (stmt); | |
662 | if (TREE_CODE (val2) == SSA_NAME) | |
663 | { | |
664 | gimple def_stmt = SSA_NAME_DEF_STMT (val2); | |
665 | if (is_gimple_assign (def_stmt) | |
666 | && gimple_assign_rhs_code (def_stmt) == gimple_assign_rhs_code (stmt) | |
667 | && operand_equal_p (gimple_assign_rhs1 (def_stmt), cond, 0)) | |
668 | { | |
669 | val2 = unshare_expr (gimple_assign_rhs3 (def_stmt)); | |
670 | gimple_assign_set_rhs3 (stmt, val2); | |
671 | changed = true; | |
672 | } | |
673 | } | |
674 | if (operand_equal_p (val1, val2, 0)) | |
675 | { | |
676 | gimple_assign_set_rhs_from_tree (gsi_p, val1); | |
677 | stmt = gsi_stmt (*gsi_p); | |
678 | changed = true; | |
679 | } | |
680 | ||
681 | if (changed) | |
682 | update_stmt (stmt); | |
683 | ||
684 | return changed; | |
685 | } | |
686 | ||
48e1416a | 687 | /* We've just substituted an ADDR_EXPR into stmt. Update all the |
148aa112 | 688 | relevant data structures to match. */ |
689 | ||
690 | static void | |
75a70cf9 | 691 | tidy_after_forward_propagate_addr (gimple stmt) |
148aa112 | 692 | { |
148aa112 | 693 | /* We may have turned a trapping insn into a non-trapping insn. */ |
694 | if (maybe_clean_or_replace_eh_stmt (stmt, stmt) | |
75a70cf9 | 695 | && gimple_purge_dead_eh_edges (gimple_bb (stmt))) |
148aa112 | 696 | cfg_changed = true; |
f2fae51f | 697 | |
75a70cf9 | 698 | if (TREE_CODE (gimple_assign_rhs1 (stmt)) == ADDR_EXPR) |
699 | recompute_tree_invariant_for_addr_expr (gimple_assign_rhs1 (stmt)); | |
148aa112 | 700 | } |
701 | ||
75a70cf9 | 702 | /* DEF_RHS contains the address of the 0th element in an array. |
6c01267c | 703 | USE_STMT uses type of DEF_RHS to compute the address of an |
291d763b | 704 | arbitrary element within the array. The (variable) byte offset |
705 | of the element is contained in OFFSET. | |
706 | ||
707 | We walk back through the use-def chains of OFFSET to verify that | |
708 | it is indeed computing the offset of an element within the array | |
709 | and extract the index corresponding to the given byte offset. | |
710 | ||
711 | We then try to fold the entire address expression into a form | |
712 | &array[index]. | |
713 | ||
714 | If we are successful, we replace the right hand side of USE_STMT | |
715 | with the new address computation. */ | |
716 | ||
717 | static bool | |
6c01267c | 718 | forward_propagate_addr_into_variable_array_index (tree offset, |
75a70cf9 | 719 | tree def_rhs, |
720 | gimple_stmt_iterator *use_stmt_gsi) | |
291d763b | 721 | { |
401d1fb3 | 722 | tree index, tunit; |
75a70cf9 | 723 | gimple offset_def, use_stmt = gsi_stmt (*use_stmt_gsi); |
182cf5a9 | 724 | tree new_rhs, tmp; |
401d1fb3 | 725 | |
182cf5a9 | 726 | if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF) |
727 | tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs))); | |
728 | else if (TREE_CODE (TREE_TYPE (TREE_OPERAND (def_rhs, 0))) == ARRAY_TYPE) | |
729 | tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs)))); | |
730 | else | |
731 | return false; | |
401d1fb3 | 732 | if (!host_integerp (tunit, 1)) |
733 | return false; | |
291d763b | 734 | |
65c220cd | 735 | /* Get the offset's defining statement. */ |
736 | offset_def = SSA_NAME_DEF_STMT (offset); | |
737 | ||
738 | /* Try to find an expression for a proper index. This is either a | |
739 | multiplication expression by the element size or just the ssa name we came | |
740 | along in case the element size is one. In that case, however, we do not | |
741 | allow multiplications because they can be computing index to a higher | |
742 | level dimension (PR 37861). */ | |
401d1fb3 | 743 | if (integer_onep (tunit)) |
1a773ec5 | 744 | { |
65c220cd | 745 | if (is_gimple_assign (offset_def) |
746 | && gimple_assign_rhs_code (offset_def) == MULT_EXPR) | |
747 | return false; | |
291d763b | 748 | |
65c220cd | 749 | index = offset; |
750 | } | |
751 | else | |
752 | { | |
0de36bdb | 753 | /* The statement which defines OFFSET before type conversion |
75a70cf9 | 754 | must be a simple GIMPLE_ASSIGN. */ |
65c220cd | 755 | if (!is_gimple_assign (offset_def)) |
1a773ec5 | 756 | return false; |
291d763b | 757 | |
0de36bdb | 758 | /* The RHS of the statement which defines OFFSET must be a |
48e1416a | 759 | multiplication of an object by the size of the array elements. |
0de36bdb | 760 | This implicitly verifies that the size of the array elements |
761 | is constant. */ | |
401d1fb3 | 762 | if (gimple_assign_rhs_code (offset_def) == MULT_EXPR |
763 | && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST | |
764 | && tree_int_cst_equal (gimple_assign_rhs2 (offset_def), tunit)) | |
765 | { | |
766 | /* The first operand to the MULT_EXPR is the desired index. */ | |
767 | index = gimple_assign_rhs1 (offset_def); | |
768 | } | |
769 | /* If we have idx * tunit + CST * tunit re-associate that. */ | |
770 | else if ((gimple_assign_rhs_code (offset_def) == PLUS_EXPR | |
771 | || gimple_assign_rhs_code (offset_def) == MINUS_EXPR) | |
772 | && TREE_CODE (gimple_assign_rhs1 (offset_def)) == SSA_NAME | |
773 | && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST | |
774 | && (tmp = div_if_zero_remainder (EXACT_DIV_EXPR, | |
775 | gimple_assign_rhs2 (offset_def), | |
776 | tunit)) != NULL_TREE) | |
777 | { | |
778 | gimple offset_def2 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (offset_def)); | |
507b89a4 | 779 | if (is_gimple_assign (offset_def2) |
780 | && gimple_assign_rhs_code (offset_def2) == MULT_EXPR | |
401d1fb3 | 781 | && TREE_CODE (gimple_assign_rhs2 (offset_def2)) == INTEGER_CST |
782 | && tree_int_cst_equal (gimple_assign_rhs2 (offset_def2), tunit)) | |
783 | { | |
784 | index = fold_build2 (gimple_assign_rhs_code (offset_def), | |
785 | TREE_TYPE (offset), | |
786 | gimple_assign_rhs1 (offset_def2), tmp); | |
787 | } | |
788 | else | |
789 | return false; | |
790 | } | |
791 | else | |
1a773ec5 | 792 | return false; |
1a773ec5 | 793 | } |
291d763b | 794 | |
795 | /* Replace the pointer addition with array indexing. */ | |
401d1fb3 | 796 | index = force_gimple_operand_gsi (use_stmt_gsi, index, true, NULL_TREE, |
797 | true, GSI_SAME_STMT); | |
182cf5a9 | 798 | if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF) |
799 | { | |
800 | new_rhs = unshare_expr (def_rhs); | |
801 | TREE_OPERAND (TREE_OPERAND (new_rhs, 0), 1) = index; | |
802 | } | |
803 | else | |
804 | { | |
805 | new_rhs = build4 (ARRAY_REF, TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs))), | |
806 | unshare_expr (TREE_OPERAND (def_rhs, 0)), | |
807 | index, integer_zero_node, NULL_TREE); | |
808 | new_rhs = build_fold_addr_expr (new_rhs); | |
809 | if (!useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (use_stmt)), | |
810 | TREE_TYPE (new_rhs))) | |
811 | { | |
812 | new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs, true, | |
813 | NULL_TREE, true, GSI_SAME_STMT); | |
814 | new_rhs = fold_convert (TREE_TYPE (gimple_assign_lhs (use_stmt)), | |
815 | new_rhs); | |
816 | } | |
817 | } | |
818 | gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); | |
50aacf4c | 819 | fold_stmt (use_stmt_gsi); |
820 | tidy_after_forward_propagate_addr (gsi_stmt (*use_stmt_gsi)); | |
291d763b | 821 | return true; |
822 | } | |
823 | ||
15ec875c | 824 | /* NAME is a SSA_NAME representing DEF_RHS which is of the form |
825 | ADDR_EXPR <whatever>. | |
291d763b | 826 | |
3d5cfe81 | 827 | Try to forward propagate the ADDR_EXPR into the use USE_STMT. |
291d763b | 828 | Often this will allow for removal of an ADDR_EXPR and INDIRECT_REF |
3d5cfe81 | 829 | node or for recovery of array indexing from pointer arithmetic. |
75a70cf9 | 830 | |
6b5a5c42 | 831 | Return true if the propagation was successful (the propagation can |
832 | be not totally successful, yet things may have been changed). */ | |
291d763b | 833 | |
834 | static bool | |
75a70cf9 | 835 | forward_propagate_addr_expr_1 (tree name, tree def_rhs, |
836 | gimple_stmt_iterator *use_stmt_gsi, | |
6776dec8 | 837 | bool single_use_p) |
291d763b | 838 | { |
75a70cf9 | 839 | tree lhs, rhs, rhs2, array_ref; |
75a70cf9 | 840 | gimple use_stmt = gsi_stmt (*use_stmt_gsi); |
841 | enum tree_code rhs_code; | |
9e019299 | 842 | bool res = true; |
291d763b | 843 | |
971c637a | 844 | gcc_assert (TREE_CODE (def_rhs) == ADDR_EXPR); |
291d763b | 845 | |
75a70cf9 | 846 | lhs = gimple_assign_lhs (use_stmt); |
847 | rhs_code = gimple_assign_rhs_code (use_stmt); | |
848 | rhs = gimple_assign_rhs1 (use_stmt); | |
15ec875c | 849 | |
6776dec8 | 850 | /* Trivial cases. The use statement could be a trivial copy or a |
15ec875c | 851 | useless conversion. Recurse to the uses of the lhs as copyprop does |
971c637a | 852 | not copy through different variant pointers and FRE does not catch |
6776dec8 | 853 | all useless conversions. Treat the case of a single-use name and |
854 | a conversion to def_rhs type separate, though. */ | |
971c637a | 855 | if (TREE_CODE (lhs) == SSA_NAME |
75a70cf9 | 856 | && ((rhs_code == SSA_NAME && rhs == name) |
316616c9 | 857 | || CONVERT_EXPR_CODE_P (rhs_code))) |
6776dec8 | 858 | { |
316616c9 | 859 | /* Only recurse if we don't deal with a single use or we cannot |
860 | do the propagation to the current statement. In particular | |
861 | we can end up with a conversion needed for a non-invariant | |
862 | address which we cannot do in a single statement. */ | |
863 | if (!single_use_p | |
864 | || (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs)) | |
bd8d8d81 | 865 | && (!is_gimple_min_invariant (def_rhs) |
866 | || (INTEGRAL_TYPE_P (TREE_TYPE (lhs)) | |
867 | && POINTER_TYPE_P (TREE_TYPE (def_rhs)) | |
868 | && (TYPE_PRECISION (TREE_TYPE (lhs)) | |
869 | > TYPE_PRECISION (TREE_TYPE (def_rhs))))))) | |
971c637a | 870 | return forward_propagate_addr_expr (lhs, def_rhs); |
871 | ||
75a70cf9 | 872 | gimple_assign_set_rhs1 (use_stmt, unshare_expr (def_rhs)); |
316616c9 | 873 | if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs))) |
874 | gimple_assign_set_rhs_code (use_stmt, TREE_CODE (def_rhs)); | |
875 | else | |
876 | gimple_assign_set_rhs_code (use_stmt, NOP_EXPR); | |
6776dec8 | 877 | return true; |
878 | } | |
971c637a | 879 | |
182cf5a9 | 880 | /* Propagate through constant pointer adjustments. */ |
881 | if (TREE_CODE (lhs) == SSA_NAME | |
882 | && rhs_code == POINTER_PLUS_EXPR | |
883 | && rhs == name | |
884 | && TREE_CODE (gimple_assign_rhs2 (use_stmt)) == INTEGER_CST) | |
885 | { | |
886 | tree new_def_rhs; | |
887 | /* As we come here with non-invariant addresses in def_rhs we need | |
888 | to make sure we can build a valid constant offsetted address | |
889 | for further propagation. Simply rely on fold building that | |
890 | and check after the fact. */ | |
891 | new_def_rhs = fold_build2 (MEM_REF, TREE_TYPE (TREE_TYPE (rhs)), | |
892 | def_rhs, | |
893 | fold_convert (ptr_type_node, | |
894 | gimple_assign_rhs2 (use_stmt))); | |
895 | if (TREE_CODE (new_def_rhs) == MEM_REF | |
f5d03f27 | 896 | && !is_gimple_mem_ref_addr (TREE_OPERAND (new_def_rhs, 0))) |
182cf5a9 | 897 | return false; |
898 | new_def_rhs = build_fold_addr_expr_with_type (new_def_rhs, | |
899 | TREE_TYPE (rhs)); | |
900 | ||
901 | /* Recurse. If we could propagate into all uses of lhs do not | |
902 | bother to replace into the current use but just pretend we did. */ | |
903 | if (TREE_CODE (new_def_rhs) == ADDR_EXPR | |
904 | && forward_propagate_addr_expr (lhs, new_def_rhs)) | |
905 | return true; | |
906 | ||
907 | if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (new_def_rhs))) | |
908 | gimple_assign_set_rhs_with_ops (use_stmt_gsi, TREE_CODE (new_def_rhs), | |
909 | new_def_rhs, NULL_TREE); | |
910 | else if (is_gimple_min_invariant (new_def_rhs)) | |
911 | gimple_assign_set_rhs_with_ops (use_stmt_gsi, NOP_EXPR, | |
912 | new_def_rhs, NULL_TREE); | |
913 | else | |
914 | return false; | |
915 | gcc_assert (gsi_stmt (*use_stmt_gsi) == use_stmt); | |
916 | update_stmt (use_stmt); | |
917 | return true; | |
918 | } | |
919 | ||
48e1416a | 920 | /* Now strip away any outer COMPONENT_REF/ARRAY_REF nodes from the LHS. |
971c637a | 921 | ADDR_EXPR will not appear on the LHS. */ |
182cf5a9 | 922 | lhs = gimple_assign_lhs (use_stmt); |
923 | while (handled_component_p (lhs)) | |
924 | lhs = TREE_OPERAND (lhs, 0); | |
971c637a | 925 | |
182cf5a9 | 926 | /* Now see if the LHS node is a MEM_REF using NAME. If so, |
971c637a | 927 | propagate the ADDR_EXPR into the use of NAME and fold the result. */ |
182cf5a9 | 928 | if (TREE_CODE (lhs) == MEM_REF |
9e019299 | 929 | && TREE_OPERAND (lhs, 0) == name) |
971c637a | 930 | { |
182cf5a9 | 931 | tree def_rhs_base; |
932 | HOST_WIDE_INT def_rhs_offset; | |
933 | /* If the address is invariant we can always fold it. */ | |
934 | if ((def_rhs_base = get_addr_base_and_unit_offset (TREE_OPERAND (def_rhs, 0), | |
935 | &def_rhs_offset))) | |
9e019299 | 936 | { |
182cf5a9 | 937 | double_int off = mem_ref_offset (lhs); |
938 | tree new_ptr; | |
939 | off = double_int_add (off, | |
940 | shwi_to_double_int (def_rhs_offset)); | |
941 | if (TREE_CODE (def_rhs_base) == MEM_REF) | |
942 | { | |
943 | off = double_int_add (off, mem_ref_offset (def_rhs_base)); | |
944 | new_ptr = TREE_OPERAND (def_rhs_base, 0); | |
945 | } | |
946 | else | |
947 | new_ptr = build_fold_addr_expr (def_rhs_base); | |
948 | TREE_OPERAND (lhs, 0) = new_ptr; | |
949 | TREE_OPERAND (lhs, 1) | |
950 | = double_int_to_tree (TREE_TYPE (TREE_OPERAND (lhs, 1)), off); | |
9e019299 | 951 | tidy_after_forward_propagate_addr (use_stmt); |
9e019299 | 952 | /* Continue propagating into the RHS if this was not the only use. */ |
953 | if (single_use_p) | |
954 | return true; | |
955 | } | |
182cf5a9 | 956 | /* If the LHS is a plain dereference and the value type is the same as |
957 | that of the pointed-to type of the address we can put the | |
958 | dereferenced address on the LHS preserving the original alias-type. */ | |
959 | else if (gimple_assign_lhs (use_stmt) == lhs | |
b97e39a0 | 960 | && integer_zerop (TREE_OPERAND (lhs, 1)) |
182cf5a9 | 961 | && useless_type_conversion_p |
962 | (TREE_TYPE (TREE_OPERAND (def_rhs, 0)), | |
963 | TREE_TYPE (gimple_assign_rhs1 (use_stmt)))) | |
964 | { | |
965 | tree *def_rhs_basep = &TREE_OPERAND (def_rhs, 0); | |
98d96c6f | 966 | tree new_offset, new_base, saved, new_lhs; |
182cf5a9 | 967 | while (handled_component_p (*def_rhs_basep)) |
968 | def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0); | |
969 | saved = *def_rhs_basep; | |
970 | if (TREE_CODE (*def_rhs_basep) == MEM_REF) | |
971 | { | |
972 | new_base = TREE_OPERAND (*def_rhs_basep, 0); | |
b97e39a0 | 973 | new_offset = fold_convert (TREE_TYPE (TREE_OPERAND (lhs, 1)), |
974 | TREE_OPERAND (*def_rhs_basep, 1)); | |
182cf5a9 | 975 | } |
976 | else | |
977 | { | |
978 | new_base = build_fold_addr_expr (*def_rhs_basep); | |
979 | new_offset = TREE_OPERAND (lhs, 1); | |
980 | } | |
981 | *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), | |
982 | new_base, new_offset); | |
2e5dc41c | 983 | TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (lhs); |
31fa5b0d | 984 | TREE_SIDE_EFFECTS (*def_rhs_basep) = TREE_SIDE_EFFECTS (lhs); |
2e5dc41c | 985 | TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (lhs); |
98d96c6f | 986 | new_lhs = unshare_expr (TREE_OPERAND (def_rhs, 0)); |
987 | gimple_assign_set_lhs (use_stmt, new_lhs); | |
988 | TREE_THIS_VOLATILE (new_lhs) = TREE_THIS_VOLATILE (lhs); | |
31fa5b0d | 989 | TREE_SIDE_EFFECTS (new_lhs) = TREE_SIDE_EFFECTS (lhs); |
182cf5a9 | 990 | *def_rhs_basep = saved; |
991 | tidy_after_forward_propagate_addr (use_stmt); | |
992 | /* Continue propagating into the RHS if this was not the | |
993 | only use. */ | |
994 | if (single_use_p) | |
995 | return true; | |
996 | } | |
9e019299 | 997 | else |
998 | /* We can have a struct assignment dereferencing our name twice. | |
999 | Note that we didn't propagate into the lhs to not falsely | |
1000 | claim we did when propagating into the rhs. */ | |
1001 | res = false; | |
971c637a | 1002 | } |
15ec875c | 1003 | |
631d5db6 | 1004 | /* Strip away any outer COMPONENT_REF, ARRAY_REF or ADDR_EXPR |
1005 | nodes from the RHS. */ | |
182cf5a9 | 1006 | rhs = gimple_assign_rhs1 (use_stmt); |
1007 | if (TREE_CODE (rhs) == ADDR_EXPR) | |
1008 | rhs = TREE_OPERAND (rhs, 0); | |
1009 | while (handled_component_p (rhs)) | |
1010 | rhs = TREE_OPERAND (rhs, 0); | |
291d763b | 1011 | |
182cf5a9 | 1012 | /* Now see if the RHS node is a MEM_REF using NAME. If so, |
291d763b | 1013 | propagate the ADDR_EXPR into the use of NAME and fold the result. */ |
182cf5a9 | 1014 | if (TREE_CODE (rhs) == MEM_REF |
1015 | && TREE_OPERAND (rhs, 0) == name) | |
291d763b | 1016 | { |
182cf5a9 | 1017 | tree def_rhs_base; |
1018 | HOST_WIDE_INT def_rhs_offset; | |
1019 | if ((def_rhs_base = get_addr_base_and_unit_offset (TREE_OPERAND (def_rhs, 0), | |
1020 | &def_rhs_offset))) | |
1021 | { | |
1022 | double_int off = mem_ref_offset (rhs); | |
1023 | tree new_ptr; | |
1024 | off = double_int_add (off, | |
1025 | shwi_to_double_int (def_rhs_offset)); | |
1026 | if (TREE_CODE (def_rhs_base) == MEM_REF) | |
1027 | { | |
1028 | off = double_int_add (off, mem_ref_offset (def_rhs_base)); | |
1029 | new_ptr = TREE_OPERAND (def_rhs_base, 0); | |
1030 | } | |
1031 | else | |
1032 | new_ptr = build_fold_addr_expr (def_rhs_base); | |
1033 | TREE_OPERAND (rhs, 0) = new_ptr; | |
1034 | TREE_OPERAND (rhs, 1) | |
1035 | = double_int_to_tree (TREE_TYPE (TREE_OPERAND (rhs, 1)), off); | |
50aacf4c | 1036 | fold_stmt_inplace (use_stmt_gsi); |
182cf5a9 | 1037 | tidy_after_forward_propagate_addr (use_stmt); |
1038 | return res; | |
1039 | } | |
2e5dc41c | 1040 | /* If the RHS is a plain dereference and the value type is the same as |
182cf5a9 | 1041 | that of the pointed-to type of the address we can put the |
2e5dc41c | 1042 | dereferenced address on the RHS preserving the original alias-type. */ |
182cf5a9 | 1043 | else if (gimple_assign_rhs1 (use_stmt) == rhs |
b97e39a0 | 1044 | && integer_zerop (TREE_OPERAND (rhs, 1)) |
182cf5a9 | 1045 | && useless_type_conversion_p |
1046 | (TREE_TYPE (gimple_assign_lhs (use_stmt)), | |
1047 | TREE_TYPE (TREE_OPERAND (def_rhs, 0)))) | |
1048 | { | |
1049 | tree *def_rhs_basep = &TREE_OPERAND (def_rhs, 0); | |
98d96c6f | 1050 | tree new_offset, new_base, saved, new_rhs; |
182cf5a9 | 1051 | while (handled_component_p (*def_rhs_basep)) |
1052 | def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0); | |
1053 | saved = *def_rhs_basep; | |
1054 | if (TREE_CODE (*def_rhs_basep) == MEM_REF) | |
1055 | { | |
1056 | new_base = TREE_OPERAND (*def_rhs_basep, 0); | |
b97e39a0 | 1057 | new_offset = fold_convert (TREE_TYPE (TREE_OPERAND (rhs, 1)), |
1058 | TREE_OPERAND (*def_rhs_basep, 1)); | |
182cf5a9 | 1059 | } |
1060 | else | |
1061 | { | |
1062 | new_base = build_fold_addr_expr (*def_rhs_basep); | |
1063 | new_offset = TREE_OPERAND (rhs, 1); | |
1064 | } | |
1065 | *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), | |
1066 | new_base, new_offset); | |
2e5dc41c | 1067 | TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (rhs); |
31fa5b0d | 1068 | TREE_SIDE_EFFECTS (*def_rhs_basep) = TREE_SIDE_EFFECTS (rhs); |
2e5dc41c | 1069 | TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (rhs); |
98d96c6f | 1070 | new_rhs = unshare_expr (TREE_OPERAND (def_rhs, 0)); |
1071 | gimple_assign_set_rhs1 (use_stmt, new_rhs); | |
1072 | TREE_THIS_VOLATILE (new_rhs) = TREE_THIS_VOLATILE (rhs); | |
31fa5b0d | 1073 | TREE_SIDE_EFFECTS (new_rhs) = TREE_SIDE_EFFECTS (rhs); |
182cf5a9 | 1074 | *def_rhs_basep = saved; |
50aacf4c | 1075 | fold_stmt_inplace (use_stmt_gsi); |
182cf5a9 | 1076 | tidy_after_forward_propagate_addr (use_stmt); |
1077 | return res; | |
1078 | } | |
291d763b | 1079 | } |
1080 | ||
971c637a | 1081 | /* If the use of the ADDR_EXPR is not a POINTER_PLUS_EXPR, there |
1082 | is nothing to do. */ | |
75a70cf9 | 1083 | if (gimple_assign_rhs_code (use_stmt) != POINTER_PLUS_EXPR |
1084 | || gimple_assign_rhs1 (use_stmt) != name) | |
971c637a | 1085 | return false; |
1086 | ||
291d763b | 1087 | /* The remaining cases are all for turning pointer arithmetic into |
1088 | array indexing. They only apply when we have the address of | |
1089 | element zero in an array. If that is not the case then there | |
1090 | is nothing to do. */ | |
15ec875c | 1091 | array_ref = TREE_OPERAND (def_rhs, 0); |
182cf5a9 | 1092 | if ((TREE_CODE (array_ref) != ARRAY_REF |
1093 | || TREE_CODE (TREE_TYPE (TREE_OPERAND (array_ref, 0))) != ARRAY_TYPE | |
1094 | || TREE_CODE (TREE_OPERAND (array_ref, 1)) != INTEGER_CST) | |
1095 | && TREE_CODE (TREE_TYPE (array_ref)) != ARRAY_TYPE) | |
291d763b | 1096 | return false; |
1097 | ||
75a70cf9 | 1098 | rhs2 = gimple_assign_rhs2 (use_stmt); |
704d7315 | 1099 | /* Optimize &x[C1] p+ C2 to &x p+ C3 with C3 = C1 * element_size + C2. */ |
75a70cf9 | 1100 | if (TREE_CODE (rhs2) == INTEGER_CST) |
291d763b | 1101 | { |
704d7315 | 1102 | tree new_rhs = build1_loc (gimple_location (use_stmt), |
1103 | ADDR_EXPR, TREE_TYPE (def_rhs), | |
1104 | fold_build2 (MEM_REF, | |
1105 | TREE_TYPE (TREE_TYPE (def_rhs)), | |
1106 | unshare_expr (def_rhs), | |
1107 | fold_convert (ptr_type_node, | |
1108 | rhs2))); | |
1109 | gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); | |
1110 | use_stmt = gsi_stmt (*use_stmt_gsi); | |
1111 | update_stmt (use_stmt); | |
1112 | tidy_after_forward_propagate_addr (use_stmt); | |
1113 | return true; | |
291d763b | 1114 | } |
1115 | ||
0de36bdb | 1116 | /* Try to optimize &x[0] p+ OFFSET where OFFSET is defined by |
291d763b | 1117 | converting a multiplication of an index by the size of the |
1118 | array elements, then the result is converted into the proper | |
1119 | type for the arithmetic. */ | |
75a70cf9 | 1120 | if (TREE_CODE (rhs2) == SSA_NAME |
182cf5a9 | 1121 | && (TREE_CODE (array_ref) != ARRAY_REF |
1122 | || integer_zerop (TREE_OPERAND (array_ref, 1))) | |
c019af4d | 1123 | && useless_type_conversion_p (TREE_TYPE (name), TREE_TYPE (def_rhs)) |
291d763b | 1124 | /* Avoid problems with IVopts creating PLUS_EXPRs with a |
1125 | different type than their operands. */ | |
83a99d39 | 1126 | && useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs))) |
75a70cf9 | 1127 | return forward_propagate_addr_into_variable_array_index (rhs2, def_rhs, |
1128 | use_stmt_gsi); | |
291d763b | 1129 | return false; |
1130 | } | |
1131 | ||
3d5cfe81 | 1132 | /* STMT is a statement of the form SSA_NAME = ADDR_EXPR <whatever>. |
1133 | ||
1134 | Try to forward propagate the ADDR_EXPR into all uses of the SSA_NAME. | |
1135 | Often this will allow for removal of an ADDR_EXPR and INDIRECT_REF | |
1136 | node or for recovery of array indexing from pointer arithmetic. | |
1137 | Returns true, if all uses have been propagated into. */ | |
1138 | ||
1139 | static bool | |
15ec875c | 1140 | forward_propagate_addr_expr (tree name, tree rhs) |
3d5cfe81 | 1141 | { |
75a70cf9 | 1142 | int stmt_loop_depth = gimple_bb (SSA_NAME_DEF_STMT (name))->loop_depth; |
3d5cfe81 | 1143 | imm_use_iterator iter; |
75a70cf9 | 1144 | gimple use_stmt; |
3d5cfe81 | 1145 | bool all = true; |
6776dec8 | 1146 | bool single_use_p = has_single_use (name); |
3d5cfe81 | 1147 | |
09aca5bc | 1148 | FOR_EACH_IMM_USE_STMT (use_stmt, iter, name) |
3d5cfe81 | 1149 | { |
c96420f8 | 1150 | bool result; |
9481f629 | 1151 | tree use_rhs; |
3d5cfe81 | 1152 | |
1153 | /* If the use is not in a simple assignment statement, then | |
1154 | there is nothing we can do. */ | |
75a70cf9 | 1155 | if (gimple_code (use_stmt) != GIMPLE_ASSIGN) |
3d5cfe81 | 1156 | { |
688ff29b | 1157 | if (!is_gimple_debug (use_stmt)) |
9845d120 | 1158 | all = false; |
3d5cfe81 | 1159 | continue; |
1160 | } | |
1161 | ||
a540e2fe | 1162 | /* If the use is in a deeper loop nest, then we do not want |
ed40c3d0 | 1163 | to propagate non-invariant ADDR_EXPRs into the loop as that |
1164 | is likely adding expression evaluations into the loop. */ | |
1165 | if (gimple_bb (use_stmt)->loop_depth > stmt_loop_depth | |
1166 | && !is_gimple_min_invariant (rhs)) | |
3d5cfe81 | 1167 | { |
1168 | all = false; | |
1169 | continue; | |
1170 | } | |
a540e2fe | 1171 | |
75a70cf9 | 1172 | { |
1173 | gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); | |
1174 | result = forward_propagate_addr_expr_1 (name, rhs, &gsi, | |
1175 | single_use_p); | |
dd277d48 | 1176 | /* If the use has moved to a different statement adjust |
4c5fd53c | 1177 | the update machinery for the old statement too. */ |
dd277d48 | 1178 | if (use_stmt != gsi_stmt (gsi)) |
1179 | { | |
dd277d48 | 1180 | update_stmt (use_stmt); |
4c5fd53c | 1181 | use_stmt = gsi_stmt (gsi); |
dd277d48 | 1182 | } |
4c5fd53c | 1183 | |
1184 | update_stmt (use_stmt); | |
75a70cf9 | 1185 | } |
c96420f8 | 1186 | all &= result; |
de6ed584 | 1187 | |
15ec875c | 1188 | /* Remove intermediate now unused copy and conversion chains. */ |
75a70cf9 | 1189 | use_rhs = gimple_assign_rhs1 (use_stmt); |
15ec875c | 1190 | if (result |
75a70cf9 | 1191 | && TREE_CODE (gimple_assign_lhs (use_stmt)) == SSA_NAME |
7b705d94 | 1192 | && TREE_CODE (use_rhs) == SSA_NAME |
1193 | && has_zero_uses (gimple_assign_lhs (use_stmt))) | |
15ec875c | 1194 | { |
75a70cf9 | 1195 | gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); |
15ec875c | 1196 | release_defs (use_stmt); |
75a70cf9 | 1197 | gsi_remove (&gsi, true); |
15ec875c | 1198 | } |
3d5cfe81 | 1199 | } |
1200 | ||
628ce22b | 1201 | return all && has_zero_uses (name); |
3d5cfe81 | 1202 | } |
1203 | ||
678b2f5b | 1204 | |
1205 | /* Forward propagate the comparison defined in STMT like | |
1206 | cond_1 = x CMP y to uses of the form | |
1207 | a_1 = (T')cond_1 | |
1208 | a_1 = !cond_1 | |
1209 | a_1 = cond_1 != 0 | |
1210 | Returns true if stmt is now unused. */ | |
1211 | ||
1212 | static bool | |
1213 | forward_propagate_comparison (gimple stmt) | |
1214 | { | |
1215 | tree name = gimple_assign_lhs (stmt); | |
1216 | gimple use_stmt; | |
1217 | tree tmp = NULL_TREE; | |
e5b1e080 | 1218 | gimple_stmt_iterator gsi; |
1219 | enum tree_code code; | |
1220 | tree lhs; | |
678b2f5b | 1221 | |
1222 | /* Don't propagate ssa names that occur in abnormal phis. */ | |
1223 | if ((TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME | |
1224 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_assign_rhs1 (stmt))) | |
1225 | || (TREE_CODE (gimple_assign_rhs2 (stmt)) == SSA_NAME | |
1226 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_assign_rhs2 (stmt)))) | |
1227 | return false; | |
1228 | ||
1229 | /* Do not un-cse comparisons. But propagate through copies. */ | |
1230 | use_stmt = get_prop_dest_stmt (name, &name); | |
e5b1e080 | 1231 | if (!use_stmt |
1232 | || !is_gimple_assign (use_stmt)) | |
678b2f5b | 1233 | return false; |
1234 | ||
e5b1e080 | 1235 | code = gimple_assign_rhs_code (use_stmt); |
1236 | lhs = gimple_assign_lhs (use_stmt); | |
1237 | if (!INTEGRAL_TYPE_P (TREE_TYPE (lhs))) | |
1238 | return false; | |
678b2f5b | 1239 | |
e5b1e080 | 1240 | /* We can propagate the condition into a statement that |
1241 | computes the logical negation of the comparison result. */ | |
4b5f1658 | 1242 | if ((code == BIT_NOT_EXPR |
1243 | && TYPE_PRECISION (TREE_TYPE (lhs)) == 1) | |
1244 | || (code == BIT_XOR_EXPR | |
1245 | && integer_onep (gimple_assign_rhs2 (use_stmt)))) | |
e5b1e080 | 1246 | { |
1247 | tree type = TREE_TYPE (gimple_assign_rhs1 (stmt)); | |
1248 | bool nans = HONOR_NANS (TYPE_MODE (type)); | |
1249 | enum tree_code inv_code; | |
1250 | inv_code = invert_tree_comparison (gimple_assign_rhs_code (stmt), nans); | |
1251 | if (inv_code == ERROR_MARK) | |
678b2f5b | 1252 | return false; |
1253 | ||
e5b1e080 | 1254 | tmp = build2 (inv_code, TREE_TYPE (lhs), gimple_assign_rhs1 (stmt), |
1255 | gimple_assign_rhs2 (stmt)); | |
1256 | } | |
1257 | else | |
1258 | return false; | |
678b2f5b | 1259 | |
e5b1e080 | 1260 | gsi = gsi_for_stmt (use_stmt); |
1261 | gimple_assign_set_rhs_from_tree (&gsi, unshare_expr (tmp)); | |
1262 | use_stmt = gsi_stmt (gsi); | |
1263 | update_stmt (use_stmt); | |
678b2f5b | 1264 | |
e5b1e080 | 1265 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1266 | { | |
1267 | fprintf (dump_file, " Replaced '"); | |
1268 | print_gimple_expr (dump_file, stmt, 0, dump_flags); | |
1269 | fprintf (dump_file, "' with '"); | |
1270 | print_gimple_expr (dump_file, use_stmt, 0, dump_flags); | |
1271 | fprintf (dump_file, "'\n"); | |
678b2f5b | 1272 | } |
1273 | ||
e5b1e080 | 1274 | /* Remove defining statements. */ |
1275 | return remove_prop_source_from_use (name); | |
678b2f5b | 1276 | } |
1277 | ||
1278 | ||
3a938499 | 1279 | /* If we have lhs = ~x (STMT), look and see if earlier we had x = ~y. |
1280 | If so, we can change STMT into lhs = y which can later be copy | |
48e1416a | 1281 | propagated. Similarly for negation. |
3a938499 | 1282 | |
48e1416a | 1283 | This could trivially be formulated as a forward propagation |
3a938499 | 1284 | to immediate uses. However, we already had an implementation |
1285 | from DOM which used backward propagation via the use-def links. | |
1286 | ||
1287 | It turns out that backward propagation is actually faster as | |
1288 | there's less work to do for each NOT/NEG expression we find. | |
1289 | Backwards propagation needs to look at the statement in a single | |
1290 | backlink. Forward propagation needs to look at potentially more | |
678b2f5b | 1291 | than one forward link. |
3a938499 | 1292 | |
678b2f5b | 1293 | Returns true when the statement was changed. */ |
1294 | ||
1295 | static bool | |
75a70cf9 | 1296 | simplify_not_neg_expr (gimple_stmt_iterator *gsi_p) |
3a938499 | 1297 | { |
75a70cf9 | 1298 | gimple stmt = gsi_stmt (*gsi_p); |
1299 | tree rhs = gimple_assign_rhs1 (stmt); | |
1300 | gimple rhs_def_stmt = SSA_NAME_DEF_STMT (rhs); | |
3a938499 | 1301 | |
1302 | /* See if the RHS_DEF_STMT has the same form as our statement. */ | |
75a70cf9 | 1303 | if (is_gimple_assign (rhs_def_stmt) |
1304 | && gimple_assign_rhs_code (rhs_def_stmt) == gimple_assign_rhs_code (stmt)) | |
3a938499 | 1305 | { |
75a70cf9 | 1306 | tree rhs_def_operand = gimple_assign_rhs1 (rhs_def_stmt); |
3a938499 | 1307 | |
1308 | /* Verify that RHS_DEF_OPERAND is a suitable SSA_NAME. */ | |
1309 | if (TREE_CODE (rhs_def_operand) == SSA_NAME | |
1310 | && ! SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs_def_operand)) | |
1311 | { | |
75a70cf9 | 1312 | gimple_assign_set_rhs_from_tree (gsi_p, rhs_def_operand); |
1313 | stmt = gsi_stmt (*gsi_p); | |
3a938499 | 1314 | update_stmt (stmt); |
678b2f5b | 1315 | return true; |
3a938499 | 1316 | } |
1317 | } | |
678b2f5b | 1318 | |
1319 | return false; | |
3a938499 | 1320 | } |
3d5cfe81 | 1321 | |
b5860aba | 1322 | /* STMT is a SWITCH_EXPR for which we attempt to find equivalent forms of |
1323 | the condition which we may be able to optimize better. */ | |
1324 | ||
678b2f5b | 1325 | static bool |
75a70cf9 | 1326 | simplify_gimple_switch (gimple stmt) |
b5860aba | 1327 | { |
75a70cf9 | 1328 | tree cond = gimple_switch_index (stmt); |
b5860aba | 1329 | tree def, to, ti; |
75a70cf9 | 1330 | gimple def_stmt; |
b5860aba | 1331 | |
1332 | /* The optimization that we really care about is removing unnecessary | |
1333 | casts. That will let us do much better in propagating the inferred | |
1334 | constant at the switch target. */ | |
1335 | if (TREE_CODE (cond) == SSA_NAME) | |
1336 | { | |
75a70cf9 | 1337 | def_stmt = SSA_NAME_DEF_STMT (cond); |
1338 | if (is_gimple_assign (def_stmt)) | |
b5860aba | 1339 | { |
75a70cf9 | 1340 | if (gimple_assign_rhs_code (def_stmt) == NOP_EXPR) |
b5860aba | 1341 | { |
1342 | int need_precision; | |
1343 | bool fail; | |
1344 | ||
75a70cf9 | 1345 | def = gimple_assign_rhs1 (def_stmt); |
b5860aba | 1346 | |
b5860aba | 1347 | /* ??? Why was Jeff testing this? We are gimple... */ |
1b4345f7 | 1348 | gcc_checking_assert (is_gimple_val (def)); |
b5860aba | 1349 | |
1350 | to = TREE_TYPE (cond); | |
1351 | ti = TREE_TYPE (def); | |
1352 | ||
1353 | /* If we have an extension that preserves value, then we | |
1354 | can copy the source value into the switch. */ | |
1355 | ||
1356 | need_precision = TYPE_PRECISION (ti); | |
1357 | fail = false; | |
c5237b8b | 1358 | if (! INTEGRAL_TYPE_P (ti)) |
1359 | fail = true; | |
1360 | else if (TYPE_UNSIGNED (to) && !TYPE_UNSIGNED (ti)) | |
b5860aba | 1361 | fail = true; |
1362 | else if (!TYPE_UNSIGNED (to) && TYPE_UNSIGNED (ti)) | |
1363 | need_precision += 1; | |
1364 | if (TYPE_PRECISION (to) < need_precision) | |
1365 | fail = true; | |
1366 | ||
1367 | if (!fail) | |
1368 | { | |
75a70cf9 | 1369 | gimple_switch_set_index (stmt, def); |
b5860aba | 1370 | update_stmt (stmt); |
678b2f5b | 1371 | return true; |
b5860aba | 1372 | } |
1373 | } | |
1374 | } | |
1375 | } | |
678b2f5b | 1376 | |
1377 | return false; | |
b5860aba | 1378 | } |
1379 | ||
27f931ff | 1380 | /* For pointers p2 and p1 return p2 - p1 if the |
1381 | difference is known and constant, otherwise return NULL. */ | |
1382 | ||
1383 | static tree | |
1384 | constant_pointer_difference (tree p1, tree p2) | |
1385 | { | |
1386 | int i, j; | |
1387 | #define CPD_ITERATIONS 5 | |
1388 | tree exps[2][CPD_ITERATIONS]; | |
1389 | tree offs[2][CPD_ITERATIONS]; | |
1390 | int cnt[2]; | |
1391 | ||
1392 | for (i = 0; i < 2; i++) | |
1393 | { | |
1394 | tree p = i ? p1 : p2; | |
1395 | tree off = size_zero_node; | |
1396 | gimple stmt; | |
1397 | enum tree_code code; | |
1398 | ||
1399 | /* For each of p1 and p2 we need to iterate at least | |
1400 | twice, to handle ADDR_EXPR directly in p1/p2, | |
1401 | SSA_NAME with ADDR_EXPR or POINTER_PLUS_EXPR etc. | |
1402 | on definition's stmt RHS. Iterate a few extra times. */ | |
1403 | j = 0; | |
1404 | do | |
1405 | { | |
1406 | if (!POINTER_TYPE_P (TREE_TYPE (p))) | |
1407 | break; | |
1408 | if (TREE_CODE (p) == ADDR_EXPR) | |
1409 | { | |
1410 | tree q = TREE_OPERAND (p, 0); | |
1411 | HOST_WIDE_INT offset; | |
1412 | tree base = get_addr_base_and_unit_offset (q, &offset); | |
1413 | if (base) | |
1414 | { | |
1415 | q = base; | |
1416 | if (offset) | |
1417 | off = size_binop (PLUS_EXPR, off, size_int (offset)); | |
1418 | } | |
1419 | if (TREE_CODE (q) == MEM_REF | |
1420 | && TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME) | |
1421 | { | |
1422 | p = TREE_OPERAND (q, 0); | |
1423 | off = size_binop (PLUS_EXPR, off, | |
1424 | double_int_to_tree (sizetype, | |
1425 | mem_ref_offset (q))); | |
1426 | } | |
1427 | else | |
1428 | { | |
1429 | exps[i][j] = q; | |
1430 | offs[i][j++] = off; | |
1431 | break; | |
1432 | } | |
1433 | } | |
1434 | if (TREE_CODE (p) != SSA_NAME) | |
1435 | break; | |
1436 | exps[i][j] = p; | |
1437 | offs[i][j++] = off; | |
1438 | if (j == CPD_ITERATIONS) | |
1439 | break; | |
1440 | stmt = SSA_NAME_DEF_STMT (p); | |
1441 | if (!is_gimple_assign (stmt) || gimple_assign_lhs (stmt) != p) | |
1442 | break; | |
1443 | code = gimple_assign_rhs_code (stmt); | |
1444 | if (code == POINTER_PLUS_EXPR) | |
1445 | { | |
1446 | if (TREE_CODE (gimple_assign_rhs2 (stmt)) != INTEGER_CST) | |
1447 | break; | |
1448 | off = size_binop (PLUS_EXPR, off, gimple_assign_rhs2 (stmt)); | |
1449 | p = gimple_assign_rhs1 (stmt); | |
1450 | } | |
1451 | else if (code == ADDR_EXPR || code == NOP_EXPR) | |
1452 | p = gimple_assign_rhs1 (stmt); | |
1453 | else | |
1454 | break; | |
1455 | } | |
1456 | while (1); | |
1457 | cnt[i] = j; | |
1458 | } | |
1459 | ||
1460 | for (i = 0; i < cnt[0]; i++) | |
1461 | for (j = 0; j < cnt[1]; j++) | |
1462 | if (exps[0][i] == exps[1][j]) | |
1463 | return size_binop (MINUS_EXPR, offs[0][i], offs[1][j]); | |
1464 | ||
1465 | return NULL_TREE; | |
1466 | } | |
1467 | ||
1468 | /* *GSI_P is a GIMPLE_CALL to a builtin function. | |
1469 | Optimize | |
1470 | memcpy (p, "abcd", 4); | |
1471 | memset (p + 4, ' ', 3); | |
1472 | into | |
1473 | memcpy (p, "abcd ", 7); | |
1474 | call if the latter can be stored by pieces during expansion. */ | |
1475 | ||
1476 | static bool | |
1477 | simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2) | |
1478 | { | |
1479 | gimple stmt1, stmt2 = gsi_stmt (*gsi_p); | |
1480 | tree vuse = gimple_vuse (stmt2); | |
1481 | if (vuse == NULL) | |
1482 | return false; | |
1483 | stmt1 = SSA_NAME_DEF_STMT (vuse); | |
1484 | ||
1485 | switch (DECL_FUNCTION_CODE (callee2)) | |
1486 | { | |
1487 | case BUILT_IN_MEMSET: | |
1488 | if (gimple_call_num_args (stmt2) != 3 | |
1489 | || gimple_call_lhs (stmt2) | |
1490 | || CHAR_BIT != 8 | |
1491 | || BITS_PER_UNIT != 8) | |
1492 | break; | |
1493 | else | |
1494 | { | |
1495 | tree callee1; | |
1496 | tree ptr1, src1, str1, off1, len1, lhs1; | |
1497 | tree ptr2 = gimple_call_arg (stmt2, 0); | |
1498 | tree val2 = gimple_call_arg (stmt2, 1); | |
1499 | tree len2 = gimple_call_arg (stmt2, 2); | |
1500 | tree diff, vdef, new_str_cst; | |
1501 | gimple use_stmt; | |
1502 | unsigned int ptr1_align; | |
1503 | unsigned HOST_WIDE_INT src_len; | |
1504 | char *src_buf; | |
1505 | use_operand_p use_p; | |
1506 | ||
1507 | if (!host_integerp (val2, 0) | |
1508 | || !host_integerp (len2, 1)) | |
1509 | break; | |
1510 | if (is_gimple_call (stmt1)) | |
1511 | { | |
1512 | /* If first stmt is a call, it needs to be memcpy | |
1513 | or mempcpy, with string literal as second argument and | |
1514 | constant length. */ | |
1515 | callee1 = gimple_call_fndecl (stmt1); | |
1516 | if (callee1 == NULL_TREE | |
1517 | || DECL_BUILT_IN_CLASS (callee1) != BUILT_IN_NORMAL | |
1518 | || gimple_call_num_args (stmt1) != 3) | |
1519 | break; | |
1520 | if (DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMCPY | |
1521 | && DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMPCPY) | |
1522 | break; | |
1523 | ptr1 = gimple_call_arg (stmt1, 0); | |
1524 | src1 = gimple_call_arg (stmt1, 1); | |
1525 | len1 = gimple_call_arg (stmt1, 2); | |
1526 | lhs1 = gimple_call_lhs (stmt1); | |
1527 | if (!host_integerp (len1, 1)) | |
1528 | break; | |
1529 | str1 = string_constant (src1, &off1); | |
1530 | if (str1 == NULL_TREE) | |
1531 | break; | |
1532 | if (!host_integerp (off1, 1) | |
1533 | || compare_tree_int (off1, TREE_STRING_LENGTH (str1) - 1) > 0 | |
1534 | || compare_tree_int (len1, TREE_STRING_LENGTH (str1) | |
1535 | - tree_low_cst (off1, 1)) > 0 | |
1536 | || TREE_CODE (TREE_TYPE (str1)) != ARRAY_TYPE | |
1537 | || TYPE_MODE (TREE_TYPE (TREE_TYPE (str1))) | |
1538 | != TYPE_MODE (char_type_node)) | |
1539 | break; | |
1540 | } | |
1541 | else if (gimple_assign_single_p (stmt1)) | |
1542 | { | |
1543 | /* Otherwise look for length 1 memcpy optimized into | |
1544 | assignment. */ | |
1545 | ptr1 = gimple_assign_lhs (stmt1); | |
1546 | src1 = gimple_assign_rhs1 (stmt1); | |
1547 | if (TREE_CODE (ptr1) != MEM_REF | |
1548 | || TYPE_MODE (TREE_TYPE (ptr1)) != TYPE_MODE (char_type_node) | |
1549 | || !host_integerp (src1, 0)) | |
1550 | break; | |
1551 | ptr1 = build_fold_addr_expr (ptr1); | |
1552 | callee1 = NULL_TREE; | |
1553 | len1 = size_one_node; | |
1554 | lhs1 = NULL_TREE; | |
1555 | off1 = size_zero_node; | |
1556 | str1 = NULL_TREE; | |
1557 | } | |
1558 | else | |
1559 | break; | |
1560 | ||
1561 | diff = constant_pointer_difference (ptr1, ptr2); | |
1562 | if (diff == NULL && lhs1 != NULL) | |
1563 | { | |
1564 | diff = constant_pointer_difference (lhs1, ptr2); | |
1565 | if (DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY | |
1566 | && diff != NULL) | |
1567 | diff = size_binop (PLUS_EXPR, diff, | |
1568 | fold_convert (sizetype, len1)); | |
1569 | } | |
1570 | /* If the difference between the second and first destination pointer | |
1571 | is not constant, or is bigger than memcpy length, bail out. */ | |
1572 | if (diff == NULL | |
1573 | || !host_integerp (diff, 1) | |
1574 | || tree_int_cst_lt (len1, diff)) | |
1575 | break; | |
1576 | ||
1577 | /* Use maximum of difference plus memset length and memcpy length | |
1578 | as the new memcpy length, if it is too big, bail out. */ | |
1579 | src_len = tree_low_cst (diff, 1); | |
1580 | src_len += tree_low_cst (len2, 1); | |
1581 | if (src_len < (unsigned HOST_WIDE_INT) tree_low_cst (len1, 1)) | |
1582 | src_len = tree_low_cst (len1, 1); | |
1583 | if (src_len > 1024) | |
1584 | break; | |
1585 | ||
1586 | /* If mempcpy value is used elsewhere, bail out, as mempcpy | |
1587 | with bigger length will return different result. */ | |
1588 | if (lhs1 != NULL_TREE | |
1589 | && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY | |
1590 | && (TREE_CODE (lhs1) != SSA_NAME | |
1591 | || !single_imm_use (lhs1, &use_p, &use_stmt) | |
1592 | || use_stmt != stmt2)) | |
1593 | break; | |
1594 | ||
1595 | /* If anything reads memory in between memcpy and memset | |
1596 | call, the modified memcpy call might change it. */ | |
1597 | vdef = gimple_vdef (stmt1); | |
1598 | if (vdef != NULL | |
1599 | && (!single_imm_use (vdef, &use_p, &use_stmt) | |
1600 | || use_stmt != stmt2)) | |
1601 | break; | |
1602 | ||
957d0361 | 1603 | ptr1_align = get_pointer_alignment (ptr1); |
27f931ff | 1604 | /* Construct the new source string literal. */ |
1605 | src_buf = XALLOCAVEC (char, src_len + 1); | |
1606 | if (callee1) | |
1607 | memcpy (src_buf, | |
1608 | TREE_STRING_POINTER (str1) + tree_low_cst (off1, 1), | |
1609 | tree_low_cst (len1, 1)); | |
1610 | else | |
1611 | src_buf[0] = tree_low_cst (src1, 0); | |
1612 | memset (src_buf + tree_low_cst (diff, 1), | |
1613 | tree_low_cst (val2, 1), tree_low_cst (len2, 1)); | |
1614 | src_buf[src_len] = '\0'; | |
1615 | /* Neither builtin_strncpy_read_str nor builtin_memcpy_read_str | |
1616 | handle embedded '\0's. */ | |
1617 | if (strlen (src_buf) != src_len) | |
1618 | break; | |
1619 | rtl_profile_for_bb (gimple_bb (stmt2)); | |
1620 | /* If the new memcpy wouldn't be emitted by storing the literal | |
1621 | by pieces, this optimization might enlarge .rodata too much, | |
1622 | as commonly used string literals couldn't be shared any | |
1623 | longer. */ | |
1624 | if (!can_store_by_pieces (src_len, | |
1625 | builtin_strncpy_read_str, | |
1626 | src_buf, ptr1_align, false)) | |
1627 | break; | |
1628 | ||
1629 | new_str_cst = build_string_literal (src_len, src_buf); | |
1630 | if (callee1) | |
1631 | { | |
1632 | /* If STMT1 is a mem{,p}cpy call, adjust it and remove | |
1633 | memset call. */ | |
1634 | if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY) | |
1635 | gimple_call_set_lhs (stmt1, NULL_TREE); | |
1636 | gimple_call_set_arg (stmt1, 1, new_str_cst); | |
1637 | gimple_call_set_arg (stmt1, 2, | |
1638 | build_int_cst (TREE_TYPE (len1), src_len)); | |
1639 | update_stmt (stmt1); | |
1640 | unlink_stmt_vdef (stmt2); | |
1641 | gsi_remove (gsi_p, true); | |
1642 | release_defs (stmt2); | |
1643 | if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY) | |
1644 | release_ssa_name (lhs1); | |
1645 | return true; | |
1646 | } | |
1647 | else | |
1648 | { | |
1649 | /* Otherwise, if STMT1 is length 1 memcpy optimized into | |
1650 | assignment, remove STMT1 and change memset call into | |
1651 | memcpy call. */ | |
1652 | gimple_stmt_iterator gsi = gsi_for_stmt (stmt1); | |
1653 | ||
7ecb2e7c | 1654 | if (!is_gimple_val (ptr1)) |
1655 | ptr1 = force_gimple_operand_gsi (gsi_p, ptr1, true, NULL_TREE, | |
1656 | true, GSI_SAME_STMT); | |
b9a16870 | 1657 | gimple_call_set_fndecl (stmt2, |
1658 | builtin_decl_explicit (BUILT_IN_MEMCPY)); | |
27f931ff | 1659 | gimple_call_set_arg (stmt2, 0, ptr1); |
1660 | gimple_call_set_arg (stmt2, 1, new_str_cst); | |
1661 | gimple_call_set_arg (stmt2, 2, | |
1662 | build_int_cst (TREE_TYPE (len2), src_len)); | |
1663 | unlink_stmt_vdef (stmt1); | |
1664 | gsi_remove (&gsi, true); | |
1665 | release_defs (stmt1); | |
1666 | update_stmt (stmt2); | |
1667 | return false; | |
1668 | } | |
1669 | } | |
1670 | break; | |
1671 | default: | |
1672 | break; | |
1673 | } | |
1674 | return false; | |
1675 | } | |
1676 | ||
41913fa9 | 1677 | /* Checks if expression has type of one-bit precision, or is a known |
1678 | truth-valued expression. */ | |
1679 | static bool | |
1680 | truth_valued_ssa_name (tree name) | |
1681 | { | |
1682 | gimple def; | |
1683 | tree type = TREE_TYPE (name); | |
1684 | ||
1685 | if (!INTEGRAL_TYPE_P (type)) | |
1686 | return false; | |
1687 | /* Don't check here for BOOLEAN_TYPE as the precision isn't | |
1688 | necessarily one and so ~X is not equal to !X. */ | |
1689 | if (TYPE_PRECISION (type) == 1) | |
1690 | return true; | |
1691 | def = SSA_NAME_DEF_STMT (name); | |
1692 | if (is_gimple_assign (def)) | |
1693 | return truth_value_p (gimple_assign_rhs_code (def)); | |
1694 | return false; | |
1695 | } | |
1696 | ||
1697 | /* Helper routine for simplify_bitwise_binary_1 function. | |
1698 | Return for the SSA name NAME the expression X if it mets condition | |
1699 | NAME = !X. Otherwise return NULL_TREE. | |
1700 | Detected patterns for NAME = !X are: | |
1701 | !X and X == 0 for X with integral type. | |
1702 | X ^ 1, X != 1,or ~X for X with integral type with precision of one. */ | |
1703 | static tree | |
1704 | lookup_logical_inverted_value (tree name) | |
1705 | { | |
1706 | tree op1, op2; | |
1707 | enum tree_code code; | |
1708 | gimple def; | |
1709 | ||
1710 | /* If name has none-intergal type, or isn't a SSA_NAME, then | |
1711 | return. */ | |
1712 | if (TREE_CODE (name) != SSA_NAME | |
1713 | || !INTEGRAL_TYPE_P (TREE_TYPE (name))) | |
1714 | return NULL_TREE; | |
1715 | def = SSA_NAME_DEF_STMT (name); | |
1716 | if (!is_gimple_assign (def)) | |
1717 | return NULL_TREE; | |
1718 | ||
1719 | code = gimple_assign_rhs_code (def); | |
1720 | op1 = gimple_assign_rhs1 (def); | |
1721 | op2 = NULL_TREE; | |
1722 | ||
1723 | /* Get for EQ_EXPR or BIT_XOR_EXPR operation the second operand. | |
8f4a7578 | 1724 | If CODE isn't an EQ_EXPR, BIT_XOR_EXPR, or BIT_NOT_EXPR, then return. */ |
41913fa9 | 1725 | if (code == EQ_EXPR || code == NE_EXPR |
1726 | || code == BIT_XOR_EXPR) | |
1727 | op2 = gimple_assign_rhs2 (def); | |
1728 | ||
1729 | switch (code) | |
1730 | { | |
41913fa9 | 1731 | case BIT_NOT_EXPR: |
1732 | if (truth_valued_ssa_name (name)) | |
1733 | return op1; | |
1734 | break; | |
1735 | case EQ_EXPR: | |
1736 | /* Check if we have X == 0 and X has an integral type. */ | |
1737 | if (!INTEGRAL_TYPE_P (TREE_TYPE (op1))) | |
1738 | break; | |
1739 | if (integer_zerop (op2)) | |
1740 | return op1; | |
1741 | break; | |
1742 | case NE_EXPR: | |
1743 | /* Check if we have X != 1 and X is a truth-valued. */ | |
1744 | if (!INTEGRAL_TYPE_P (TREE_TYPE (op1))) | |
1745 | break; | |
1746 | if (integer_onep (op2) && truth_valued_ssa_name (op1)) | |
1747 | return op1; | |
1748 | break; | |
1749 | case BIT_XOR_EXPR: | |
1750 | /* Check if we have X ^ 1 and X is truth valued. */ | |
1751 | if (integer_onep (op2) && truth_valued_ssa_name (op1)) | |
1752 | return op1; | |
1753 | break; | |
1754 | default: | |
1755 | break; | |
1756 | } | |
1757 | ||
1758 | return NULL_TREE; | |
1759 | } | |
1760 | ||
1761 | /* Optimize ARG1 CODE ARG2 to a constant for bitwise binary | |
1762 | operations CODE, if one operand has the logically inverted | |
1763 | value of the other. */ | |
1764 | static tree | |
1765 | simplify_bitwise_binary_1 (enum tree_code code, tree type, | |
1766 | tree arg1, tree arg2) | |
1767 | { | |
1768 | tree anot; | |
1769 | ||
1770 | /* If CODE isn't a bitwise binary operation, return NULL_TREE. */ | |
1771 | if (code != BIT_AND_EXPR && code != BIT_IOR_EXPR | |
1772 | && code != BIT_XOR_EXPR) | |
1773 | return NULL_TREE; | |
1774 | ||
1775 | /* First check if operands ARG1 and ARG2 are equal. If so | |
1776 | return NULL_TREE as this optimization is handled fold_stmt. */ | |
1777 | if (arg1 == arg2) | |
1778 | return NULL_TREE; | |
1779 | /* See if we have in arguments logical-not patterns. */ | |
1780 | if (((anot = lookup_logical_inverted_value (arg1)) == NULL_TREE | |
1781 | || anot != arg2) | |
1782 | && ((anot = lookup_logical_inverted_value (arg2)) == NULL_TREE | |
1783 | || anot != arg1)) | |
1784 | return NULL_TREE; | |
1785 | ||
1786 | /* X & !X -> 0. */ | |
1787 | if (code == BIT_AND_EXPR) | |
1788 | return fold_convert (type, integer_zero_node); | |
1789 | /* X | !X -> 1 and X ^ !X -> 1, if X is truth-valued. */ | |
1790 | if (truth_valued_ssa_name (anot)) | |
1791 | return fold_convert (type, integer_one_node); | |
1792 | ||
1793 | /* ??? Otherwise result is (X != 0 ? X : 1). not handled. */ | |
1794 | return NULL_TREE; | |
1795 | } | |
1796 | ||
300da094 | 1797 | /* Simplify bitwise binary operations. |
1798 | Return true if a transformation applied, otherwise return false. */ | |
1c4607fd | 1799 | |
300da094 | 1800 | static bool |
1801 | simplify_bitwise_binary (gimple_stmt_iterator *gsi) | |
1c4607fd | 1802 | { |
300da094 | 1803 | gimple stmt = gsi_stmt (*gsi); |
1c4607fd | 1804 | tree arg1 = gimple_assign_rhs1 (stmt); |
1805 | tree arg2 = gimple_assign_rhs2 (stmt); | |
300da094 | 1806 | enum tree_code code = gimple_assign_rhs_code (stmt); |
1807 | tree res; | |
26f54bd0 | 1808 | gimple def1 = NULL, def2 = NULL; |
1809 | tree def1_arg1, def2_arg1; | |
1810 | enum tree_code def1_code, def2_code; | |
1c4607fd | 1811 | |
26f54bd0 | 1812 | def1_code = TREE_CODE (arg1); |
1813 | def1_arg1 = arg1; | |
1814 | if (TREE_CODE (arg1) == SSA_NAME) | |
1815 | { | |
1816 | def1 = SSA_NAME_DEF_STMT (arg1); | |
1817 | if (is_gimple_assign (def1)) | |
1818 | { | |
1819 | def1_code = gimple_assign_rhs_code (def1); | |
1820 | def1_arg1 = gimple_assign_rhs1 (def1); | |
1821 | } | |
1822 | } | |
1823 | ||
1824 | def2_code = TREE_CODE (arg2); | |
1825 | def2_arg1 = arg2; | |
1826 | if (TREE_CODE (arg2) == SSA_NAME) | |
1827 | { | |
1828 | def2 = SSA_NAME_DEF_STMT (arg2); | |
1829 | if (is_gimple_assign (def2)) | |
1830 | { | |
1831 | def2_code = gimple_assign_rhs_code (def2); | |
1832 | def2_arg1 = gimple_assign_rhs1 (def2); | |
1833 | } | |
1834 | } | |
1835 | ||
25ce0d90 | 1836 | /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST)). */ |
1837 | if (TREE_CODE (arg2) == INTEGER_CST | |
1838 | && CONVERT_EXPR_CODE_P (def1_code) | |
105fc895 | 1839 | && INTEGRAL_TYPE_P (TREE_TYPE (def1_arg1)) |
25ce0d90 | 1840 | && int_fits_type_p (arg2, TREE_TYPE (def1_arg1))) |
1841 | { | |
1842 | gimple newop; | |
1843 | tree tem = create_tmp_reg (TREE_TYPE (def1_arg1), NULL); | |
1844 | newop = | |
1845 | gimple_build_assign_with_ops (code, tem, def1_arg1, | |
1846 | fold_convert_loc (gimple_location (stmt), | |
1847 | TREE_TYPE (def1_arg1), | |
1848 | arg2)); | |
1849 | tem = make_ssa_name (tem, newop); | |
1850 | gimple_assign_set_lhs (newop, tem); | |
4b5f1658 | 1851 | gimple_set_location (newop, gimple_location (stmt)); |
25ce0d90 | 1852 | gsi_insert_before (gsi, newop, GSI_SAME_STMT); |
1853 | gimple_assign_set_rhs_with_ops_1 (gsi, NOP_EXPR, | |
1854 | tem, NULL_TREE, NULL_TREE); | |
1855 | update_stmt (gsi_stmt (*gsi)); | |
1856 | return true; | |
1857 | } | |
1858 | ||
300da094 | 1859 | /* For bitwise binary operations apply operand conversions to the |
1860 | binary operation result instead of to the operands. This allows | |
1861 | to combine successive conversions and bitwise binary operations. */ | |
26f54bd0 | 1862 | if (CONVERT_EXPR_CODE_P (def1_code) |
1863 | && CONVERT_EXPR_CODE_P (def2_code) | |
1864 | && types_compatible_p (TREE_TYPE (def1_arg1), TREE_TYPE (def2_arg1)) | |
25ce0d90 | 1865 | /* Make sure that the conversion widens the operands, or has same |
1866 | precision, or that it changes the operation to a bitfield | |
1867 | precision. */ | |
26f54bd0 | 1868 | && ((TYPE_PRECISION (TREE_TYPE (def1_arg1)) |
25ce0d90 | 1869 | <= TYPE_PRECISION (TREE_TYPE (arg1))) |
26f54bd0 | 1870 | || (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (arg1))) |
1871 | != MODE_INT) | |
1872 | || (TYPE_PRECISION (TREE_TYPE (arg1)) | |
1873 | != GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (arg1)))))) | |
1c4607fd | 1874 | { |
26f54bd0 | 1875 | gimple newop; |
1876 | tree tem = create_tmp_reg (TREE_TYPE (def1_arg1), | |
1877 | NULL); | |
1878 | newop = gimple_build_assign_with_ops (code, tem, def1_arg1, def2_arg1); | |
1879 | tem = make_ssa_name (tem, newop); | |
1880 | gimple_assign_set_lhs (newop, tem); | |
4b5f1658 | 1881 | gimple_set_location (newop, gimple_location (stmt)); |
26f54bd0 | 1882 | gsi_insert_before (gsi, newop, GSI_SAME_STMT); |
1883 | gimple_assign_set_rhs_with_ops_1 (gsi, NOP_EXPR, | |
1884 | tem, NULL_TREE, NULL_TREE); | |
1885 | update_stmt (gsi_stmt (*gsi)); | |
1886 | return true; | |
1887 | } | |
1888 | ||
1889 | /* (a | CST1) & CST2 -> (a & CST2) | (CST1 & CST2). */ | |
1890 | if (code == BIT_AND_EXPR | |
1891 | && def1_code == BIT_IOR_EXPR | |
1892 | && TREE_CODE (arg2) == INTEGER_CST | |
1893 | && TREE_CODE (gimple_assign_rhs2 (def1)) == INTEGER_CST) | |
1894 | { | |
1895 | tree cst = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg2), | |
1896 | arg2, gimple_assign_rhs2 (def1)); | |
1897 | tree tem; | |
1898 | gimple newop; | |
1899 | if (integer_zerop (cst)) | |
300da094 | 1900 | { |
26f54bd0 | 1901 | gimple_assign_set_rhs1 (stmt, def1_arg1); |
1902 | update_stmt (stmt); | |
1903 | return true; | |
300da094 | 1904 | } |
26f54bd0 | 1905 | tem = create_tmp_reg (TREE_TYPE (arg2), NULL); |
1906 | newop = gimple_build_assign_with_ops (BIT_AND_EXPR, | |
1907 | tem, def1_arg1, arg2); | |
1908 | tem = make_ssa_name (tem, newop); | |
1909 | gimple_assign_set_lhs (newop, tem); | |
4b5f1658 | 1910 | gimple_set_location (newop, gimple_location (stmt)); |
26f54bd0 | 1911 | /* Make sure to re-process the new stmt as it's walking upwards. */ |
1912 | gsi_insert_before (gsi, newop, GSI_NEW_STMT); | |
1913 | gimple_assign_set_rhs1 (stmt, tem); | |
1914 | gimple_assign_set_rhs2 (stmt, cst); | |
1915 | gimple_assign_set_rhs_code (stmt, BIT_IOR_EXPR); | |
1916 | update_stmt (stmt); | |
1917 | return true; | |
1918 | } | |
1919 | ||
1920 | /* Combine successive equal operations with constants. */ | |
1921 | if ((code == BIT_AND_EXPR | |
1922 | || code == BIT_IOR_EXPR | |
1923 | || code == BIT_XOR_EXPR) | |
1924 | && def1_code == code | |
1925 | && TREE_CODE (arg2) == INTEGER_CST | |
1926 | && TREE_CODE (gimple_assign_rhs2 (def1)) == INTEGER_CST) | |
1927 | { | |
1928 | tree cst = fold_build2 (code, TREE_TYPE (arg2), | |
1929 | arg2, gimple_assign_rhs2 (def1)); | |
1930 | gimple_assign_set_rhs1 (stmt, def1_arg1); | |
1931 | gimple_assign_set_rhs2 (stmt, cst); | |
1932 | update_stmt (stmt); | |
1933 | return true; | |
1c4607fd | 1934 | } |
300da094 | 1935 | |
8a5f403f | 1936 | /* Canonicalize X ^ ~0 to ~X. */ |
1937 | if (code == BIT_XOR_EXPR | |
1938 | && TREE_CODE (arg2) == INTEGER_CST | |
1939 | && integer_all_onesp (arg2)) | |
1940 | { | |
1941 | gimple_assign_set_rhs_with_ops (gsi, BIT_NOT_EXPR, arg1, NULL_TREE); | |
1942 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
1943 | update_stmt (stmt); | |
1944 | return true; | |
1945 | } | |
1946 | ||
41913fa9 | 1947 | /* Try simple folding for X op !X, and X op X. */ |
1948 | res = simplify_bitwise_binary_1 (code, TREE_TYPE (arg1), arg1, arg2); | |
1949 | if (res != NULL_TREE) | |
1950 | { | |
1951 | gimple_assign_set_rhs_from_tree (gsi, res); | |
1952 | update_stmt (gsi_stmt (*gsi)); | |
1953 | return true; | |
1954 | } | |
1955 | ||
300da094 | 1956 | return false; |
1c4607fd | 1957 | } |
1958 | ||
ca3c9092 | 1959 | |
1960 | /* Perform re-associations of the plus or minus statement STMT that are | |
b69d1cb6 | 1961 | always permitted. Returns true if the CFG was changed. */ |
ca3c9092 | 1962 | |
b69d1cb6 | 1963 | static bool |
50aacf4c | 1964 | associate_plusminus (gimple_stmt_iterator *gsi) |
ca3c9092 | 1965 | { |
50aacf4c | 1966 | gimple stmt = gsi_stmt (*gsi); |
ca3c9092 | 1967 | tree rhs1 = gimple_assign_rhs1 (stmt); |
1968 | tree rhs2 = gimple_assign_rhs2 (stmt); | |
1969 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
ca3c9092 | 1970 | bool changed; |
1971 | ||
1972 | /* We can't reassociate at all for saturating types. */ | |
1973 | if (TYPE_SATURATING (TREE_TYPE (rhs1))) | |
b69d1cb6 | 1974 | return false; |
ca3c9092 | 1975 | |
1976 | /* First contract negates. */ | |
1977 | do | |
1978 | { | |
1979 | changed = false; | |
1980 | ||
1981 | /* A +- (-B) -> A -+ B. */ | |
1982 | if (TREE_CODE (rhs2) == SSA_NAME) | |
1983 | { | |
1984 | gimple def_stmt = SSA_NAME_DEF_STMT (rhs2); | |
1985 | if (is_gimple_assign (def_stmt) | |
32cdcc42 | 1986 | && gimple_assign_rhs_code (def_stmt) == NEGATE_EXPR |
1987 | && can_propagate_from (def_stmt)) | |
ca3c9092 | 1988 | { |
1989 | code = (code == MINUS_EXPR) ? PLUS_EXPR : MINUS_EXPR; | |
1990 | gimple_assign_set_rhs_code (stmt, code); | |
1991 | rhs2 = gimple_assign_rhs1 (def_stmt); | |
1992 | gimple_assign_set_rhs2 (stmt, rhs2); | |
1993 | gimple_set_modified (stmt, true); | |
1994 | changed = true; | |
1995 | } | |
1996 | } | |
1997 | ||
1998 | /* (-A) + B -> B - A. */ | |
1999 | if (TREE_CODE (rhs1) == SSA_NAME | |
2000 | && code == PLUS_EXPR) | |
2001 | { | |
2002 | gimple def_stmt = SSA_NAME_DEF_STMT (rhs1); | |
2003 | if (is_gimple_assign (def_stmt) | |
32cdcc42 | 2004 | && gimple_assign_rhs_code (def_stmt) == NEGATE_EXPR |
2005 | && can_propagate_from (def_stmt)) | |
ca3c9092 | 2006 | { |
2007 | code = MINUS_EXPR; | |
2008 | gimple_assign_set_rhs_code (stmt, code); | |
2009 | rhs1 = rhs2; | |
2010 | gimple_assign_set_rhs1 (stmt, rhs1); | |
2011 | rhs2 = gimple_assign_rhs1 (def_stmt); | |
2012 | gimple_assign_set_rhs2 (stmt, rhs2); | |
2013 | gimple_set_modified (stmt, true); | |
2014 | changed = true; | |
2015 | } | |
2016 | } | |
2017 | } | |
2018 | while (changed); | |
2019 | ||
2020 | /* We can't reassociate floating-point or fixed-point plus or minus | |
2021 | because of saturation to +-Inf. */ | |
2022 | if (FLOAT_TYPE_P (TREE_TYPE (rhs1)) | |
2023 | || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1))) | |
2024 | goto out; | |
2025 | ||
2026 | /* Second match patterns that allow contracting a plus-minus pair | |
2027 | irrespective of overflow issues. | |
2028 | ||
2029 | (A +- B) - A -> +- B | |
2030 | (A +- B) -+ B -> A | |
2031 | (CST +- A) +- CST -> CST +- A | |
2032 | (A + CST) +- CST -> A + CST | |
2033 | ~A + A -> -1 | |
2034 | ~A + 1 -> -A | |
2035 | A - (A +- B) -> -+ B | |
2036 | A +- (B +- A) -> +- B | |
2037 | CST +- (CST +- A) -> CST +- A | |
2038 | CST +- (A +- CST) -> CST +- A | |
2039 | A + ~A -> -1 | |
2040 | ||
2041 | via commutating the addition and contracting operations to zero | |
2042 | by reassociation. */ | |
2043 | ||
ca3c9092 | 2044 | if (TREE_CODE (rhs1) == SSA_NAME) |
2045 | { | |
2046 | gimple def_stmt = SSA_NAME_DEF_STMT (rhs1); | |
32cdcc42 | 2047 | if (is_gimple_assign (def_stmt) && can_propagate_from (def_stmt)) |
ca3c9092 | 2048 | { |
2049 | enum tree_code def_code = gimple_assign_rhs_code (def_stmt); | |
2050 | if (def_code == PLUS_EXPR | |
2051 | || def_code == MINUS_EXPR) | |
2052 | { | |
2053 | tree def_rhs1 = gimple_assign_rhs1 (def_stmt); | |
2054 | tree def_rhs2 = gimple_assign_rhs2 (def_stmt); | |
2055 | if (operand_equal_p (def_rhs1, rhs2, 0) | |
2056 | && code == MINUS_EXPR) | |
2057 | { | |
2058 | /* (A +- B) - A -> +- B. */ | |
2059 | code = ((def_code == PLUS_EXPR) | |
2060 | ? TREE_CODE (def_rhs2) : NEGATE_EXPR); | |
2061 | rhs1 = def_rhs2; | |
2062 | rhs2 = NULL_TREE; | |
50aacf4c | 2063 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2064 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2065 | gimple_set_modified (stmt, true); |
2066 | } | |
2067 | else if (operand_equal_p (def_rhs2, rhs2, 0) | |
2068 | && code != def_code) | |
2069 | { | |
2070 | /* (A +- B) -+ B -> A. */ | |
2071 | code = TREE_CODE (def_rhs1); | |
2072 | rhs1 = def_rhs1; | |
2073 | rhs2 = NULL_TREE; | |
50aacf4c | 2074 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2075 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2076 | gimple_set_modified (stmt, true); |
2077 | } | |
2078 | else if (TREE_CODE (rhs2) == INTEGER_CST | |
2079 | && TREE_CODE (def_rhs1) == INTEGER_CST) | |
2080 | { | |
2081 | /* (CST +- A) +- CST -> CST +- A. */ | |
2082 | tree cst = fold_binary (code, TREE_TYPE (rhs1), | |
2083 | def_rhs1, rhs2); | |
2084 | if (cst && !TREE_OVERFLOW (cst)) | |
2085 | { | |
2086 | code = def_code; | |
2087 | gimple_assign_set_rhs_code (stmt, code); | |
2088 | rhs1 = cst; | |
2089 | gimple_assign_set_rhs1 (stmt, rhs1); | |
2090 | rhs2 = def_rhs2; | |
2091 | gimple_assign_set_rhs2 (stmt, rhs2); | |
2092 | gimple_set_modified (stmt, true); | |
2093 | } | |
2094 | } | |
2095 | else if (TREE_CODE (rhs2) == INTEGER_CST | |
2096 | && TREE_CODE (def_rhs2) == INTEGER_CST | |
2097 | && def_code == PLUS_EXPR) | |
2098 | { | |
2099 | /* (A + CST) +- CST -> A + CST. */ | |
2100 | tree cst = fold_binary (code, TREE_TYPE (rhs1), | |
2101 | def_rhs2, rhs2); | |
2102 | if (cst && !TREE_OVERFLOW (cst)) | |
2103 | { | |
2104 | code = PLUS_EXPR; | |
2105 | gimple_assign_set_rhs_code (stmt, code); | |
2106 | rhs1 = def_rhs1; | |
2107 | gimple_assign_set_rhs1 (stmt, rhs1); | |
2108 | rhs2 = cst; | |
2109 | gimple_assign_set_rhs2 (stmt, rhs2); | |
2110 | gimple_set_modified (stmt, true); | |
2111 | } | |
2112 | } | |
2113 | } | |
2114 | else if (def_code == BIT_NOT_EXPR | |
2115 | && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) | |
2116 | { | |
2117 | tree def_rhs1 = gimple_assign_rhs1 (def_stmt); | |
2118 | if (code == PLUS_EXPR | |
2119 | && operand_equal_p (def_rhs1, rhs2, 0)) | |
2120 | { | |
2121 | /* ~A + A -> -1. */ | |
2122 | code = INTEGER_CST; | |
19d861b9 | 2123 | rhs1 = build_int_cst_type (TREE_TYPE (rhs2), -1); |
ca3c9092 | 2124 | rhs2 = NULL_TREE; |
50aacf4c | 2125 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2126 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2127 | gimple_set_modified (stmt, true); |
2128 | } | |
2129 | else if (code == PLUS_EXPR | |
2130 | && integer_onep (rhs1)) | |
2131 | { | |
2132 | /* ~A + 1 -> -A. */ | |
2133 | code = NEGATE_EXPR; | |
2134 | rhs1 = def_rhs1; | |
2135 | rhs2 = NULL_TREE; | |
50aacf4c | 2136 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2137 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2138 | gimple_set_modified (stmt, true); |
2139 | } | |
2140 | } | |
2141 | } | |
2142 | } | |
2143 | ||
2144 | if (rhs2 && TREE_CODE (rhs2) == SSA_NAME) | |
2145 | { | |
2146 | gimple def_stmt = SSA_NAME_DEF_STMT (rhs2); | |
32cdcc42 | 2147 | if (is_gimple_assign (def_stmt) && can_propagate_from (def_stmt)) |
ca3c9092 | 2148 | { |
2149 | enum tree_code def_code = gimple_assign_rhs_code (def_stmt); | |
2150 | if (def_code == PLUS_EXPR | |
2151 | || def_code == MINUS_EXPR) | |
2152 | { | |
2153 | tree def_rhs1 = gimple_assign_rhs1 (def_stmt); | |
2154 | tree def_rhs2 = gimple_assign_rhs2 (def_stmt); | |
2155 | if (operand_equal_p (def_rhs1, rhs1, 0) | |
2156 | && code == MINUS_EXPR) | |
2157 | { | |
2158 | /* A - (A +- B) -> -+ B. */ | |
2159 | code = ((def_code == PLUS_EXPR) | |
2160 | ? NEGATE_EXPR : TREE_CODE (def_rhs2)); | |
2161 | rhs1 = def_rhs2; | |
2162 | rhs2 = NULL_TREE; | |
50aacf4c | 2163 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2164 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2165 | gimple_set_modified (stmt, true); |
2166 | } | |
2167 | else if (operand_equal_p (def_rhs2, rhs1, 0) | |
2168 | && code != def_code) | |
2169 | { | |
2170 | /* A +- (B +- A) -> +- B. */ | |
2171 | code = ((code == PLUS_EXPR) | |
2172 | ? TREE_CODE (def_rhs1) : NEGATE_EXPR); | |
2173 | rhs1 = def_rhs1; | |
2174 | rhs2 = NULL_TREE; | |
50aacf4c | 2175 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2176 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2177 | gimple_set_modified (stmt, true); |
2178 | } | |
2179 | else if (TREE_CODE (rhs1) == INTEGER_CST | |
2180 | && TREE_CODE (def_rhs1) == INTEGER_CST) | |
2181 | { | |
2182 | /* CST +- (CST +- A) -> CST +- A. */ | |
2183 | tree cst = fold_binary (code, TREE_TYPE (rhs2), | |
2184 | rhs1, def_rhs1); | |
2185 | if (cst && !TREE_OVERFLOW (cst)) | |
2186 | { | |
2187 | code = (code == def_code ? PLUS_EXPR : MINUS_EXPR); | |
2188 | gimple_assign_set_rhs_code (stmt, code); | |
2189 | rhs1 = cst; | |
2190 | gimple_assign_set_rhs1 (stmt, rhs1); | |
2191 | rhs2 = def_rhs2; | |
2192 | gimple_assign_set_rhs2 (stmt, rhs2); | |
2193 | gimple_set_modified (stmt, true); | |
2194 | } | |
2195 | } | |
2196 | else if (TREE_CODE (rhs1) == INTEGER_CST | |
2197 | && TREE_CODE (def_rhs2) == INTEGER_CST) | |
2198 | { | |
2199 | /* CST +- (A +- CST) -> CST +- A. */ | |
2200 | tree cst = fold_binary (def_code == code | |
2201 | ? PLUS_EXPR : MINUS_EXPR, | |
2202 | TREE_TYPE (rhs2), | |
2203 | rhs1, def_rhs2); | |
2204 | if (cst && !TREE_OVERFLOW (cst)) | |
2205 | { | |
2206 | rhs1 = cst; | |
2207 | gimple_assign_set_rhs1 (stmt, rhs1); | |
2208 | rhs2 = def_rhs1; | |
2209 | gimple_assign_set_rhs2 (stmt, rhs2); | |
2210 | gimple_set_modified (stmt, true); | |
2211 | } | |
2212 | } | |
2213 | } | |
2214 | else if (def_code == BIT_NOT_EXPR | |
2215 | && INTEGRAL_TYPE_P (TREE_TYPE (rhs2))) | |
2216 | { | |
2217 | tree def_rhs1 = gimple_assign_rhs1 (def_stmt); | |
2218 | if (code == PLUS_EXPR | |
2219 | && operand_equal_p (def_rhs1, rhs1, 0)) | |
2220 | { | |
2221 | /* A + ~A -> -1. */ | |
2222 | code = INTEGER_CST; | |
19d861b9 | 2223 | rhs1 = build_int_cst_type (TREE_TYPE (rhs1), -1); |
ca3c9092 | 2224 | rhs2 = NULL_TREE; |
50aacf4c | 2225 | gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); |
2226 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
ca3c9092 | 2227 | gimple_set_modified (stmt, true); |
2228 | } | |
2229 | } | |
2230 | } | |
2231 | } | |
2232 | ||
2233 | out: | |
2234 | if (gimple_modified_p (stmt)) | |
2235 | { | |
50aacf4c | 2236 | fold_stmt_inplace (gsi); |
ca3c9092 | 2237 | update_stmt (stmt); |
b69d1cb6 | 2238 | if (maybe_clean_or_replace_eh_stmt (stmt, stmt) |
2239 | && gimple_purge_dead_eh_edges (gimple_bb (stmt))) | |
2240 | return true; | |
ca3c9092 | 2241 | } |
b69d1cb6 | 2242 | |
2243 | return false; | |
ca3c9092 | 2244 | } |
2245 | ||
6afd0544 | 2246 | /* Combine two conversions in a row for the second conversion at *GSI. |
89c8f35a | 2247 | Returns 1 if there were any changes made, 2 if cfg-cleanup needs to |
2248 | run. Else it returns 0. */ | |
6afd0544 | 2249 | |
89c8f35a | 2250 | static int |
6afd0544 | 2251 | combine_conversions (gimple_stmt_iterator *gsi) |
2252 | { | |
2253 | gimple stmt = gsi_stmt (*gsi); | |
2254 | gimple def_stmt; | |
2255 | tree op0, lhs; | |
2256 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
2257 | ||
2258 | gcc_checking_assert (CONVERT_EXPR_CODE_P (code) | |
2259 | || code == FLOAT_EXPR | |
2260 | || code == FIX_TRUNC_EXPR); | |
2261 | ||
2262 | lhs = gimple_assign_lhs (stmt); | |
2263 | op0 = gimple_assign_rhs1 (stmt); | |
2264 | if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (op0))) | |
2265 | { | |
2266 | gimple_assign_set_rhs_code (stmt, TREE_CODE (op0)); | |
89c8f35a | 2267 | return 1; |
6afd0544 | 2268 | } |
2269 | ||
2270 | if (TREE_CODE (op0) != SSA_NAME) | |
89c8f35a | 2271 | return 0; |
6afd0544 | 2272 | |
2273 | def_stmt = SSA_NAME_DEF_STMT (op0); | |
2274 | if (!is_gimple_assign (def_stmt)) | |
89c8f35a | 2275 | return 0; |
6afd0544 | 2276 | |
2277 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) | |
2278 | { | |
2279 | tree defop0 = gimple_assign_rhs1 (def_stmt); | |
2280 | tree type = TREE_TYPE (lhs); | |
2281 | tree inside_type = TREE_TYPE (defop0); | |
2282 | tree inter_type = TREE_TYPE (op0); | |
2283 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
2284 | int inside_ptr = POINTER_TYPE_P (inside_type); | |
2285 | int inside_float = FLOAT_TYPE_P (inside_type); | |
2286 | int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE; | |
2287 | unsigned int inside_prec = TYPE_PRECISION (inside_type); | |
2288 | int inside_unsignedp = TYPE_UNSIGNED (inside_type); | |
2289 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
2290 | int inter_ptr = POINTER_TYPE_P (inter_type); | |
2291 | int inter_float = FLOAT_TYPE_P (inter_type); | |
2292 | int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE; | |
2293 | unsigned int inter_prec = TYPE_PRECISION (inter_type); | |
2294 | int inter_unsignedp = TYPE_UNSIGNED (inter_type); | |
2295 | int final_int = INTEGRAL_TYPE_P (type); | |
2296 | int final_ptr = POINTER_TYPE_P (type); | |
2297 | int final_float = FLOAT_TYPE_P (type); | |
2298 | int final_vec = TREE_CODE (type) == VECTOR_TYPE; | |
2299 | unsigned int final_prec = TYPE_PRECISION (type); | |
2300 | int final_unsignedp = TYPE_UNSIGNED (type); | |
2301 | ||
2302 | /* In addition to the cases of two conversions in a row | |
2303 | handled below, if we are converting something to its own | |
2304 | type via an object of identical or wider precision, neither | |
2305 | conversion is needed. */ | |
2306 | if (useless_type_conversion_p (type, inside_type) | |
2307 | && (((inter_int || inter_ptr) && final_int) | |
2308 | || (inter_float && final_float)) | |
2309 | && inter_prec >= final_prec) | |
2310 | { | |
2311 | gimple_assign_set_rhs1 (stmt, unshare_expr (defop0)); | |
2312 | gimple_assign_set_rhs_code (stmt, TREE_CODE (defop0)); | |
2313 | update_stmt (stmt); | |
89c8f35a | 2314 | return remove_prop_source_from_use (op0) ? 2 : 1; |
6afd0544 | 2315 | } |
2316 | ||
2317 | /* Likewise, if the intermediate and initial types are either both | |
2318 | float or both integer, we don't need the middle conversion if the | |
2319 | former is wider than the latter and doesn't change the signedness | |
2320 | (for integers). Avoid this if the final type is a pointer since | |
2321 | then we sometimes need the middle conversion. Likewise if the | |
2322 | final type has a precision not equal to the size of its mode. */ | |
2323 | if (((inter_int && inside_int) | |
2324 | || (inter_float && inside_float) | |
2325 | || (inter_vec && inside_vec)) | |
2326 | && inter_prec >= inside_prec | |
2327 | && (inter_float || inter_vec | |
2328 | || inter_unsignedp == inside_unsignedp) | |
51dbf409 | 2329 | && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type)) |
6afd0544 | 2330 | && TYPE_MODE (type) == TYPE_MODE (inter_type)) |
2331 | && ! final_ptr | |
2332 | && (! final_vec || inter_prec == inside_prec)) | |
2333 | { | |
2334 | gimple_assign_set_rhs1 (stmt, defop0); | |
2335 | update_stmt (stmt); | |
89c8f35a | 2336 | return remove_prop_source_from_use (op0) ? 2 : 1; |
6afd0544 | 2337 | } |
2338 | ||
2339 | /* If we have a sign-extension of a zero-extended value, we can | |
a6476f88 | 2340 | replace that by a single zero-extension. Likewise if the |
2341 | final conversion does not change precision we can drop the | |
2342 | intermediate conversion. */ | |
6afd0544 | 2343 | if (inside_int && inter_int && final_int |
a6476f88 | 2344 | && ((inside_prec < inter_prec && inter_prec < final_prec |
2345 | && inside_unsignedp && !inter_unsignedp) | |
2346 | || final_prec == inter_prec)) | |
6afd0544 | 2347 | { |
2348 | gimple_assign_set_rhs1 (stmt, defop0); | |
2349 | update_stmt (stmt); | |
89c8f35a | 2350 | return remove_prop_source_from_use (op0) ? 2 : 1; |
6afd0544 | 2351 | } |
2352 | ||
2353 | /* Two conversions in a row are not needed unless: | |
2354 | - some conversion is floating-point (overstrict for now), or | |
2355 | - some conversion is a vector (overstrict for now), or | |
2356 | - the intermediate type is narrower than both initial and | |
2357 | final, or | |
2358 | - the intermediate type and innermost type differ in signedness, | |
2359 | and the outermost type is wider than the intermediate, or | |
2360 | - the initial type is a pointer type and the precisions of the | |
2361 | intermediate and final types differ, or | |
2362 | - the final type is a pointer type and the precisions of the | |
2363 | initial and intermediate types differ. */ | |
2364 | if (! inside_float && ! inter_float && ! final_float | |
2365 | && ! inside_vec && ! inter_vec && ! final_vec | |
2366 | && (inter_prec >= inside_prec || inter_prec >= final_prec) | |
2367 | && ! (inside_int && inter_int | |
2368 | && inter_unsignedp != inside_unsignedp | |
2369 | && inter_prec < final_prec) | |
2370 | && ((inter_unsignedp && inter_prec > inside_prec) | |
2371 | == (final_unsignedp && final_prec > inter_prec)) | |
2372 | && ! (inside_ptr && inter_prec != final_prec) | |
2373 | && ! (final_ptr && inside_prec != inter_prec) | |
51dbf409 | 2374 | && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type)) |
6afd0544 | 2375 | && TYPE_MODE (type) == TYPE_MODE (inter_type))) |
2376 | { | |
2377 | gimple_assign_set_rhs1 (stmt, defop0); | |
2378 | update_stmt (stmt); | |
89c8f35a | 2379 | return remove_prop_source_from_use (op0) ? 2 : 1; |
6afd0544 | 2380 | } |
2381 | ||
2382 | /* A truncation to an unsigned type should be canonicalized as | |
2383 | bitwise and of a mask. */ | |
2384 | if (final_int && inter_int && inside_int | |
2385 | && final_prec == inside_prec | |
2386 | && final_prec > inter_prec | |
2387 | && inter_unsignedp) | |
2388 | { | |
2389 | tree tem; | |
2390 | tem = fold_build2 (BIT_AND_EXPR, inside_type, | |
2391 | defop0, | |
2392 | double_int_to_tree | |
2393 | (inside_type, double_int_mask (inter_prec))); | |
2394 | if (!useless_type_conversion_p (type, inside_type)) | |
2395 | { | |
2396 | tem = force_gimple_operand_gsi (gsi, tem, true, NULL_TREE, true, | |
2397 | GSI_SAME_STMT); | |
2398 | gimple_assign_set_rhs1 (stmt, tem); | |
2399 | } | |
2400 | else | |
2401 | gimple_assign_set_rhs_from_tree (gsi, tem); | |
2402 | update_stmt (gsi_stmt (*gsi)); | |
89c8f35a | 2403 | return 1; |
6afd0544 | 2404 | } |
2405 | } | |
2406 | ||
89c8f35a | 2407 | return 0; |
6afd0544 | 2408 | } |
2409 | ||
678b2f5b | 2410 | /* Main entry point for the forward propagation and statement combine |
2411 | optimizer. */ | |
4ee9c684 | 2412 | |
2a1990e9 | 2413 | static unsigned int |
678b2f5b | 2414 | ssa_forward_propagate_and_combine (void) |
4ee9c684 | 2415 | { |
f5c8cff5 | 2416 | basic_block bb; |
c96420f8 | 2417 | unsigned int todoflags = 0; |
4ee9c684 | 2418 | |
148aa112 | 2419 | cfg_changed = false; |
2420 | ||
f5c8cff5 | 2421 | FOR_EACH_BB (bb) |
2422 | { | |
a7107e58 | 2423 | gimple_stmt_iterator gsi, prev; |
2424 | bool prev_initialized; | |
291d763b | 2425 | |
678b2f5b | 2426 | /* Apply forward propagation to all stmts in the basic-block. |
2427 | Note we update GSI within the loop as necessary. */ | |
75a70cf9 | 2428 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); ) |
291d763b | 2429 | { |
75a70cf9 | 2430 | gimple stmt = gsi_stmt (gsi); |
678b2f5b | 2431 | tree lhs, rhs; |
2432 | enum tree_code code; | |
291d763b | 2433 | |
678b2f5b | 2434 | if (!is_gimple_assign (stmt)) |
291d763b | 2435 | { |
678b2f5b | 2436 | gsi_next (&gsi); |
2437 | continue; | |
2438 | } | |
3a938499 | 2439 | |
678b2f5b | 2440 | lhs = gimple_assign_lhs (stmt); |
2441 | rhs = gimple_assign_rhs1 (stmt); | |
2442 | code = gimple_assign_rhs_code (stmt); | |
2443 | if (TREE_CODE (lhs) != SSA_NAME | |
2444 | || has_zero_uses (lhs)) | |
2445 | { | |
2446 | gsi_next (&gsi); | |
2447 | continue; | |
2448 | } | |
3a938499 | 2449 | |
678b2f5b | 2450 | /* If this statement sets an SSA_NAME to an address, |
2451 | try to propagate the address into the uses of the SSA_NAME. */ | |
2452 | if (code == ADDR_EXPR | |
2453 | /* Handle pointer conversions on invariant addresses | |
2454 | as well, as this is valid gimple. */ | |
2455 | || (CONVERT_EXPR_CODE_P (code) | |
2456 | && TREE_CODE (rhs) == ADDR_EXPR | |
2457 | && POINTER_TYPE_P (TREE_TYPE (lhs)))) | |
2458 | { | |
2459 | tree base = get_base_address (TREE_OPERAND (rhs, 0)); | |
2460 | if ((!base | |
2461 | || !DECL_P (base) | |
2462 | || decl_address_invariant_p (base)) | |
2463 | && !stmt_references_abnormal_ssa_name (stmt) | |
2464 | && forward_propagate_addr_expr (lhs, rhs)) | |
1c4607fd | 2465 | { |
678b2f5b | 2466 | release_defs (stmt); |
2467 | todoflags |= TODO_remove_unused_locals; | |
2468 | gsi_remove (&gsi, true); | |
1c4607fd | 2469 | } |
678b2f5b | 2470 | else |
2471 | gsi_next (&gsi); | |
2472 | } | |
cd22a796 | 2473 | else if (code == POINTER_PLUS_EXPR) |
678b2f5b | 2474 | { |
cd22a796 | 2475 | tree off = gimple_assign_rhs2 (stmt); |
2476 | if (TREE_CODE (off) == INTEGER_CST | |
2477 | && can_propagate_from (stmt) | |
2478 | && !simple_iv_increment_p (stmt) | |
678b2f5b | 2479 | /* ??? Better adjust the interface to that function |
2480 | instead of building new trees here. */ | |
2481 | && forward_propagate_addr_expr | |
cd22a796 | 2482 | (lhs, |
2483 | build1_loc (gimple_location (stmt), | |
2484 | ADDR_EXPR, TREE_TYPE (rhs), | |
2485 | fold_build2 (MEM_REF, | |
2486 | TREE_TYPE (TREE_TYPE (rhs)), | |
2487 | rhs, | |
2488 | fold_convert (ptr_type_node, | |
2489 | off))))) | |
ca3c9092 | 2490 | { |
678b2f5b | 2491 | release_defs (stmt); |
2492 | todoflags |= TODO_remove_unused_locals; | |
2493 | gsi_remove (&gsi, true); | |
ca3c9092 | 2494 | } |
678b2f5b | 2495 | else if (is_gimple_min_invariant (rhs)) |
6afd0544 | 2496 | { |
678b2f5b | 2497 | /* Make sure to fold &a[0] + off_1 here. */ |
50aacf4c | 2498 | fold_stmt_inplace (&gsi); |
678b2f5b | 2499 | update_stmt (stmt); |
2500 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) | |
6afd0544 | 2501 | gsi_next (&gsi); |
2502 | } | |
291d763b | 2503 | else |
75a70cf9 | 2504 | gsi_next (&gsi); |
291d763b | 2505 | } |
678b2f5b | 2506 | else if (TREE_CODE_CLASS (code) == tcc_comparison) |
b5860aba | 2507 | { |
75200312 | 2508 | if (forward_propagate_comparison (stmt)) |
2509 | cfg_changed = true; | |
75a70cf9 | 2510 | gsi_next (&gsi); |
b5860aba | 2511 | } |
291d763b | 2512 | else |
75a70cf9 | 2513 | gsi_next (&gsi); |
291d763b | 2514 | } |
678b2f5b | 2515 | |
2516 | /* Combine stmts with the stmts defining their operands. | |
2517 | Note we update GSI within the loop as necessary. */ | |
a7107e58 | 2518 | prev_initialized = false; |
2519 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);) | |
678b2f5b | 2520 | { |
2521 | gimple stmt = gsi_stmt (gsi); | |
2522 | bool changed = false; | |
2523 | ||
2524 | switch (gimple_code (stmt)) | |
2525 | { | |
2526 | case GIMPLE_ASSIGN: | |
2527 | { | |
2528 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
2529 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
2530 | ||
2531 | if ((code == BIT_NOT_EXPR | |
2532 | || code == NEGATE_EXPR) | |
2533 | && TREE_CODE (rhs1) == SSA_NAME) | |
2534 | changed = simplify_not_neg_expr (&gsi); | |
360b78f3 | 2535 | else if (code == COND_EXPR |
2536 | || code == VEC_COND_EXPR) | |
678b2f5b | 2537 | { |
2538 | /* In this case the entire COND_EXPR is in rhs1. */ | |
8a2caf10 | 2539 | changed |= forward_propagate_into_cond (&gsi); |
360b78f3 | 2540 | changed |= combine_cond_exprs (&gsi); |
678b2f5b | 2541 | stmt = gsi_stmt (gsi); |
678b2f5b | 2542 | } |
2543 | else if (TREE_CODE_CLASS (code) == tcc_comparison) | |
2544 | { | |
6f9714b3 | 2545 | int did_something; |
6f9714b3 | 2546 | did_something = forward_propagate_into_comparison (&gsi); |
2547 | if (did_something == 2) | |
2548 | cfg_changed = true; | |
6f9714b3 | 2549 | changed = did_something != 0; |
678b2f5b | 2550 | } |
2551 | else if (code == BIT_AND_EXPR | |
2552 | || code == BIT_IOR_EXPR | |
2553 | || code == BIT_XOR_EXPR) | |
2554 | changed = simplify_bitwise_binary (&gsi); | |
2555 | else if (code == PLUS_EXPR | |
2556 | || code == MINUS_EXPR) | |
50aacf4c | 2557 | changed = associate_plusminus (&gsi); |
678b2f5b | 2558 | else if (CONVERT_EXPR_CODE_P (code) |
2559 | || code == FLOAT_EXPR | |
2560 | || code == FIX_TRUNC_EXPR) | |
89c8f35a | 2561 | { |
2562 | int did_something = combine_conversions (&gsi); | |
2563 | if (did_something == 2) | |
2564 | cfg_changed = true; | |
2565 | changed = did_something != 0; | |
2566 | } | |
678b2f5b | 2567 | break; |
2568 | } | |
2569 | ||
2570 | case GIMPLE_SWITCH: | |
2571 | changed = simplify_gimple_switch (stmt); | |
2572 | break; | |
2573 | ||
2574 | case GIMPLE_COND: | |
2575 | { | |
2576 | int did_something; | |
678b2f5b | 2577 | did_something = forward_propagate_into_gimple_cond (stmt); |
2578 | if (did_something == 2) | |
2579 | cfg_changed = true; | |
678b2f5b | 2580 | changed = did_something != 0; |
2581 | break; | |
2582 | } | |
2583 | ||
2584 | case GIMPLE_CALL: | |
2585 | { | |
2586 | tree callee = gimple_call_fndecl (stmt); | |
2587 | if (callee != NULL_TREE | |
2588 | && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL) | |
2589 | changed = simplify_builtin_call (&gsi, callee); | |
2590 | break; | |
2591 | } | |
2592 | ||
2593 | default:; | |
2594 | } | |
2595 | ||
a7107e58 | 2596 | if (changed) |
2597 | { | |
2598 | /* If the stmt changed then re-visit it and the statements | |
2599 | inserted before it. */ | |
2600 | if (!prev_initialized) | |
2601 | gsi = gsi_start_bb (bb); | |
2602 | else | |
2603 | { | |
2604 | gsi = prev; | |
2605 | gsi_next (&gsi); | |
2606 | } | |
2607 | } | |
2608 | else | |
2609 | { | |
2610 | prev = gsi; | |
2611 | prev_initialized = true; | |
2612 | gsi_next (&gsi); | |
2613 | } | |
678b2f5b | 2614 | } |
f5c8cff5 | 2615 | } |
148aa112 | 2616 | |
2617 | if (cfg_changed) | |
6fa78c7b | 2618 | todoflags |= TODO_cleanup_cfg; |
678b2f5b | 2619 | |
c96420f8 | 2620 | return todoflags; |
4ee9c684 | 2621 | } |
2622 | ||
2623 | ||
2624 | static bool | |
2625 | gate_forwprop (void) | |
2626 | { | |
408c3c77 | 2627 | return flag_tree_forwprop; |
4ee9c684 | 2628 | } |
2629 | ||
48e1416a | 2630 | struct gimple_opt_pass pass_forwprop = |
20099e35 | 2631 | { |
2632 | { | |
2633 | GIMPLE_PASS, | |
4ee9c684 | 2634 | "forwprop", /* name */ |
2635 | gate_forwprop, /* gate */ | |
678b2f5b | 2636 | ssa_forward_propagate_and_combine, /* execute */ |
4ee9c684 | 2637 | NULL, /* sub */ |
2638 | NULL, /* next */ | |
2639 | 0, /* static_pass_number */ | |
2640 | TV_TREE_FORWPROP, /* tv_id */ | |
49290934 | 2641 | PROP_cfg | PROP_ssa, /* properties_required */ |
4ee9c684 | 2642 | 0, /* properties_provided */ |
b6246c40 | 2643 | 0, /* properties_destroyed */ |
4ee9c684 | 2644 | 0, /* todo_flags_start */ |
771e2890 | 2645 | TODO_ggc_collect |
de6ed584 | 2646 | | TODO_update_ssa |
20099e35 | 2647 | | TODO_verify_ssa /* todo_flags_finish */ |
2648 | } | |
4ee9c684 | 2649 | }; |