Mercurial > hg > CbC > CbC_gcc
annotate gcc/tree-ssa-live.c @ 37:d096b2ff82d9
Added tag gcc.4.4.2 for changeset 855418dad1a3
| author | e075725 |
|---|---|
| date | Tue, 22 Dec 2009 21:52:56 +0900 |
| parents | 58ad6c70ea60 |
| children | 77e2b8dfacca |
| rev | line source |
|---|---|
| 0 | 1 /* Liveness for SSA trees. |
| 2 Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009 Free Software Foundation, | |
| 3 Inc. | |
| 4 Contributed by Andrew MacLeod <amacleod@redhat.com> | |
| 5 | |
| 6 This file is part of GCC. | |
| 7 | |
| 8 GCC is free software; you can redistribute it and/or modify | |
| 9 it under the terms of the GNU General Public License as published by | |
| 10 the Free Software Foundation; either version 3, or (at your option) | |
| 11 any later version. | |
| 12 | |
| 13 GCC is distributed in the hope that it will be useful, | |
| 14 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 16 GNU General Public License for more details. | |
| 17 | |
| 18 You should have received a copy of the GNU General Public License | |
| 19 along with GCC; see the file COPYING3. If not see | |
| 20 <http://www.gnu.org/licenses/>. */ | |
| 21 | |
| 22 #include "config.h" | |
| 23 #include "system.h" | |
| 24 #include "coretypes.h" | |
| 25 #include "tm.h" | |
| 26 #include "tree.h" | |
| 27 #include "diagnostic.h" | |
| 28 #include "bitmap.h" | |
| 29 #include "tree-flow.h" | |
| 30 #include "tree-dump.h" | |
| 31 #include "tree-ssa-live.h" | |
| 32 #include "toplev.h" | |
| 33 #include "debug.h" | |
| 34 #include "flags.h" | |
| 35 | |
| 36 #ifdef ENABLE_CHECKING | |
| 37 static void verify_live_on_entry (tree_live_info_p); | |
| 38 #endif | |
| 39 | |
| 40 | |
| 41 /* VARMAP maintains a mapping from SSA version number to real variables. | |
| 42 | |
| 43 All SSA_NAMES are divided into partitions. Initially each ssa_name is the | |
| 44 only member of it's own partition. Coalescing will attempt to group any | |
| 45 ssa_names which occur in a copy or in a PHI node into the same partition. | |
| 46 | |
| 47 At the end of out-of-ssa, each partition becomes a "real" variable and is | |
| 48 rewritten as a compiler variable. | |
| 49 | |
| 50 The var_map data structure is used to manage these partitions. It allows | |
| 51 partitions to be combined, and determines which partition belongs to what | |
| 52 ssa_name or variable, and vice versa. */ | |
| 53 | |
| 54 | |
| 55 /* This routine will initialize the basevar fields of MAP. */ | |
| 56 | |
| 57 static void | |
| 58 var_map_base_init (var_map map) | |
| 59 { | |
| 60 int x, num_part, num; | |
| 61 tree var; | |
| 62 var_ann_t ann; | |
| 63 | |
| 64 num = 0; | |
| 65 num_part = num_var_partitions (map); | |
| 66 | |
| 67 /* If a base table already exists, clear it, otherwise create it. */ | |
| 68 if (map->partition_to_base_index != NULL) | |
| 69 { | |
| 70 free (map->partition_to_base_index); | |
| 71 VEC_truncate (tree, map->basevars, 0); | |
| 72 } | |
| 73 else | |
| 74 map->basevars = VEC_alloc (tree, heap, MAX (40, (num_part / 10))); | |
| 75 | |
| 76 map->partition_to_base_index = (int *) xmalloc (sizeof (int) * num_part); | |
| 77 | |
| 78 /* Build the base variable list, and point partitions at their bases. */ | |
| 79 for (x = 0; x < num_part; x++) | |
| 80 { | |
| 81 var = partition_to_var (map, x); | |
| 82 if (TREE_CODE (var) == SSA_NAME) | |
| 83 var = SSA_NAME_VAR (var); | |
| 84 ann = var_ann (var); | |
| 85 /* If base variable hasn't been seen, set it up. */ | |
| 86 if (!ann->base_var_processed) | |
| 87 { | |
| 88 ann->base_var_processed = 1; | |
| 89 VAR_ANN_BASE_INDEX (ann) = num++; | |
| 90 VEC_safe_push (tree, heap, map->basevars, var); | |
| 91 } | |
| 92 map->partition_to_base_index[x] = VAR_ANN_BASE_INDEX (ann); | |
| 93 } | |
| 94 | |
| 95 map->num_basevars = num; | |
| 96 | |
| 97 /* Now clear the processed bit. */ | |
| 98 for (x = 0; x < num; x++) | |
| 99 { | |
| 100 var = VEC_index (tree, map->basevars, x); | |
| 101 var_ann (var)->base_var_processed = 0; | |
| 102 } | |
| 103 | |
| 104 #ifdef ENABLE_CHECKING | |
| 105 for (x = 0; x < num_part; x++) | |
| 106 { | |
| 107 tree var2; | |
| 108 var = SSA_NAME_VAR (partition_to_var (map, x)); | |
| 109 var2 = VEC_index (tree, map->basevars, basevar_index (map, x)); | |
| 110 gcc_assert (var == var2); | |
| 111 } | |
| 112 #endif | |
| 113 } | |
| 114 | |
| 115 | |
| 116 /* Remove the base table in MAP. */ | |
| 117 | |
| 118 static void | |
| 119 var_map_base_fini (var_map map) | |
| 120 { | |
| 121 /* Free the basevar info if it is present. */ | |
| 122 if (map->partition_to_base_index != NULL) | |
| 123 { | |
| 124 VEC_free (tree, heap, map->basevars); | |
| 125 free (map->partition_to_base_index); | |
| 126 map->partition_to_base_index = NULL; | |
| 127 map->num_basevars = 0; | |
| 128 } | |
| 129 } | |
| 130 /* Create a variable partition map of SIZE, initialize and return it. */ | |
| 131 | |
| 132 var_map | |
| 133 init_var_map (int size) | |
| 134 { | |
| 135 var_map map; | |
| 136 | |
| 137 map = (var_map) xmalloc (sizeof (struct _var_map)); | |
| 138 map->var_partition = partition_new (size); | |
| 139 map->partition_to_var | |
| 140 = (tree *)xmalloc (size * sizeof (tree)); | |
| 141 memset (map->partition_to_var, 0, size * sizeof (tree)); | |
| 142 | |
| 143 map->partition_to_view = NULL; | |
| 144 map->view_to_partition = NULL; | |
| 145 map->num_partitions = size; | |
| 146 map->partition_size = size; | |
| 147 map->num_basevars = 0; | |
| 148 map->partition_to_base_index = NULL; | |
| 149 map->basevars = NULL; | |
| 150 return map; | |
| 151 } | |
| 152 | |
| 153 | |
| 154 /* Free memory associated with MAP. */ | |
| 155 | |
| 156 void | |
| 157 delete_var_map (var_map map) | |
| 158 { | |
| 159 var_map_base_fini (map); | |
| 160 free (map->partition_to_var); | |
| 161 partition_delete (map->var_partition); | |
| 162 if (map->partition_to_view) | |
| 163 free (map->partition_to_view); | |
| 164 if (map->view_to_partition) | |
| 165 free (map->view_to_partition); | |
| 166 free (map); | |
| 167 } | |
| 168 | |
| 169 | |
| 170 /* This function will combine the partitions in MAP for VAR1 and VAR2. It | |
| 171 Returns the partition which represents the new partition. If the two | |
| 172 partitions cannot be combined, NO_PARTITION is returned. */ | |
| 173 | |
| 174 int | |
| 175 var_union (var_map map, tree var1, tree var2) | |
| 176 { | |
| 177 int p1, p2, p3; | |
| 178 tree root_var = NULL_TREE; | |
| 179 tree other_var = NULL_TREE; | |
| 180 | |
| 181 /* This is independent of partition_to_view. If partition_to_view is | |
| 182 on, then whichever one of these partitions is absorbed will never have a | |
| 183 dereference into the partition_to_view array any more. */ | |
| 184 | |
| 185 if (TREE_CODE (var1) == SSA_NAME) | |
| 186 p1 = partition_find (map->var_partition, SSA_NAME_VERSION (var1)); | |
| 187 else | |
| 188 { | |
| 189 p1 = var_to_partition (map, var1); | |
| 190 if (map->view_to_partition) | |
| 191 p1 = map->view_to_partition[p1]; | |
| 192 root_var = var1; | |
| 193 } | |
| 194 | |
| 195 if (TREE_CODE (var2) == SSA_NAME) | |
| 196 p2 = partition_find (map->var_partition, SSA_NAME_VERSION (var2)); | |
| 197 else | |
| 198 { | |
| 199 p2 = var_to_partition (map, var2); | |
| 200 if (map->view_to_partition) | |
| 201 p2 = map->view_to_partition[p2]; | |
| 202 | |
| 203 /* If there is no root_var set, or it's not a user variable, set the | |
| 204 root_var to this one. */ | |
| 205 if (!root_var || (DECL_P (root_var) && DECL_IGNORED_P (root_var))) | |
| 206 { | |
| 207 other_var = root_var; | |
| 208 root_var = var2; | |
| 209 } | |
| 210 else | |
| 211 other_var = var2; | |
| 212 } | |
| 213 | |
| 214 gcc_assert (p1 != NO_PARTITION); | |
| 215 gcc_assert (p2 != NO_PARTITION); | |
| 216 | |
| 217 if (p1 == p2) | |
| 218 p3 = p1; | |
| 219 else | |
| 220 p3 = partition_union (map->var_partition, p1, p2); | |
| 221 | |
| 222 if (map->partition_to_view) | |
| 223 p3 = map->partition_to_view[p3]; | |
| 224 | |
| 225 if (root_var) | |
| 226 change_partition_var (map, root_var, p3); | |
| 227 if (other_var) | |
| 228 change_partition_var (map, other_var, p3); | |
| 229 | |
| 230 return p3; | |
| 231 } | |
| 232 | |
| 233 | |
| 234 /* Compress the partition numbers in MAP such that they fall in the range | |
| 235 0..(num_partitions-1) instead of wherever they turned out during | |
| 236 the partitioning exercise. This removes any references to unused | |
| 237 partitions, thereby allowing bitmaps and other vectors to be much | |
| 238 denser. | |
| 239 | |
| 240 This is implemented such that compaction doesn't affect partitioning. | |
| 241 Ie., once partitions are created and possibly merged, running one | |
| 242 or more different kind of compaction will not affect the partitions | |
| 243 themselves. Their index might change, but all the same variables will | |
| 244 still be members of the same partition group. This allows work on reduced | |
| 245 sets, and no loss of information when a larger set is later desired. | |
| 246 | |
| 247 In particular, coalescing can work on partitions which have 2 or more | |
| 248 definitions, and then 'recompact' later to include all the single | |
| 249 definitions for assignment to program variables. */ | |
| 250 | |
| 251 | |
| 252 /* Set MAP back to the initial state of having no partition view. Return a | |
| 253 bitmap which has a bit set for each partition number which is in use in the | |
| 254 varmap. */ | |
| 255 | |
| 256 static bitmap | |
| 257 partition_view_init (var_map map) | |
| 258 { | |
| 259 bitmap used; | |
| 260 int tmp; | |
| 261 unsigned int x; | |
| 262 | |
| 263 used = BITMAP_ALLOC (NULL); | |
| 264 | |
| 265 /* Already in a view? Abandon the old one. */ | |
| 266 if (map->partition_to_view) | |
| 267 { | |
| 268 free (map->partition_to_view); | |
| 269 map->partition_to_view = NULL; | |
| 270 } | |
| 271 if (map->view_to_partition) | |
| 272 { | |
| 273 free (map->view_to_partition); | |
| 274 map->view_to_partition = NULL; | |
| 275 } | |
| 276 | |
| 277 /* Find out which partitions are actually referenced. */ | |
| 278 for (x = 0; x < map->partition_size; x++) | |
| 279 { | |
| 280 tmp = partition_find (map->var_partition, x); | |
| 281 if (map->partition_to_var[tmp] != NULL_TREE && !bitmap_bit_p (used, tmp)) | |
| 282 bitmap_set_bit (used, tmp); | |
| 283 } | |
| 284 | |
| 285 map->num_partitions = map->partition_size; | |
| 286 return used; | |
| 287 } | |
| 288 | |
| 289 | |
| 290 /* This routine will finalize the view data for MAP based on the partitions | |
| 291 set in SELECTED. This is either the same bitmap returned from | |
| 292 partition_view_init, or a trimmed down version if some of those partitions | |
| 293 were not desired in this view. SELECTED is freed before returning. */ | |
| 294 | |
| 295 static void | |
| 296 partition_view_fini (var_map map, bitmap selected) | |
| 297 { | |
| 298 bitmap_iterator bi; | |
| 299 unsigned count, i, x, limit; | |
| 300 tree var; | |
| 301 | |
| 302 gcc_assert (selected); | |
| 303 | |
| 304 count = bitmap_count_bits (selected); | |
| 305 limit = map->partition_size; | |
| 306 | |
| 307 /* If its a one-to-one ratio, we don't need any view compaction. */ | |
| 308 if (count < limit) | |
| 309 { | |
| 310 map->partition_to_view = (int *)xmalloc (limit * sizeof (int)); | |
| 311 memset (map->partition_to_view, 0xff, (limit * sizeof (int))); | |
| 312 map->view_to_partition = (int *)xmalloc (count * sizeof (int)); | |
| 313 | |
| 314 i = 0; | |
| 315 /* Give each selected partition an index. */ | |
| 316 EXECUTE_IF_SET_IN_BITMAP (selected, 0, x, bi) | |
| 317 { | |
| 318 map->partition_to_view[x] = i; | |
| 319 map->view_to_partition[i] = x; | |
| 320 var = map->partition_to_var[x]; | |
| 321 /* If any one of the members of a partition is not an SSA_NAME, make | |
| 322 sure it is the representative. */ | |
| 323 if (TREE_CODE (var) != SSA_NAME) | |
| 324 change_partition_var (map, var, i); | |
| 325 i++; | |
| 326 } | |
| 327 gcc_assert (i == count); | |
| 328 map->num_partitions = i; | |
| 329 } | |
| 330 | |
| 331 BITMAP_FREE (selected); | |
| 332 } | |
| 333 | |
| 334 | |
| 335 /* Create a partition view which includes all the used partitions in MAP. If | |
| 336 WANT_BASES is true, create the base variable map as well. */ | |
| 337 | |
| 338 extern void | |
| 339 partition_view_normal (var_map map, bool want_bases) | |
| 340 { | |
| 341 bitmap used; | |
| 342 | |
| 343 used = partition_view_init (map); | |
| 344 partition_view_fini (map, used); | |
| 345 | |
| 346 if (want_bases) | |
| 347 var_map_base_init (map); | |
| 348 else | |
| 349 var_map_base_fini (map); | |
| 350 } | |
| 351 | |
| 352 | |
| 353 /* Create a partition view in MAP which includes just partitions which occur in | |
| 354 the bitmap ONLY. If WANT_BASES is true, create the base variable map | |
| 355 as well. */ | |
| 356 | |
| 357 extern void | |
| 358 partition_view_bitmap (var_map map, bitmap only, bool want_bases) | |
| 359 { | |
| 360 bitmap used; | |
| 361 bitmap new_partitions = BITMAP_ALLOC (NULL); | |
| 362 unsigned x, p; | |
| 363 bitmap_iterator bi; | |
| 364 | |
| 365 used = partition_view_init (map); | |
| 366 EXECUTE_IF_SET_IN_BITMAP (only, 0, x, bi) | |
| 367 { | |
| 368 p = partition_find (map->var_partition, x); | |
| 369 gcc_assert (bitmap_bit_p (used, p)); | |
| 370 bitmap_set_bit (new_partitions, p); | |
| 371 } | |
| 372 partition_view_fini (map, new_partitions); | |
| 373 | |
| 374 BITMAP_FREE (used); | |
| 375 if (want_bases) | |
| 376 var_map_base_init (map); | |
| 377 else | |
| 378 var_map_base_fini (map); | |
| 379 } | |
| 380 | |
| 381 | |
| 382 /* This function is used to change the representative variable in MAP for VAR's | |
| 383 partition to a regular non-ssa variable. This allows partitions to be | |
| 384 mapped back to real variables. */ | |
| 385 | |
| 386 void | |
| 387 change_partition_var (var_map map, tree var, int part) | |
| 388 { | |
| 389 var_ann_t ann; | |
| 390 | |
| 391 gcc_assert (TREE_CODE (var) != SSA_NAME); | |
| 392 | |
| 393 ann = var_ann (var); | |
| 394 ann->out_of_ssa_tag = 1; | |
| 395 VAR_ANN_PARTITION (ann) = part; | |
| 396 if (map->view_to_partition) | |
| 397 map->partition_to_var[map->view_to_partition[part]] = var; | |
| 398 } | |
| 399 | |
| 400 | |
| 401 static inline void mark_all_vars_used (tree *, void *data); | |
| 402 | |
| 403 /* Helper function for mark_all_vars_used, called via walk_tree. */ | |
| 404 | |
| 405 static tree | |
| 406 mark_all_vars_used_1 (tree *tp, int *walk_subtrees, void *data) | |
| 407 { | |
| 408 tree t = *tp; | |
| 409 enum tree_code_class c = TREE_CODE_CLASS (TREE_CODE (t)); | |
| 410 tree b; | |
| 411 | |
| 412 if (TREE_CODE (t) == SSA_NAME) | |
| 413 t = SSA_NAME_VAR (t); | |
| 414 | |
| 415 if (IS_EXPR_CODE_CLASS (c) | |
| 416 && (b = TREE_BLOCK (t)) != NULL) | |
| 417 TREE_USED (b) = true; | |
| 418 | |
| 419 /* Ignore TREE_ORIGINAL for TARGET_MEM_REFS, as well as other | |
| 420 fields that do not contain vars. */ | |
| 421 if (TREE_CODE (t) == TARGET_MEM_REF) | |
| 422 { | |
| 423 mark_all_vars_used (&TMR_SYMBOL (t), data); | |
| 424 mark_all_vars_used (&TMR_BASE (t), data); | |
| 425 mark_all_vars_used (&TMR_INDEX (t), data); | |
| 426 *walk_subtrees = 0; | |
| 427 return NULL; | |
| 428 } | |
| 429 | |
| 430 /* Only need to mark VAR_DECLS; parameters and return results are not | |
| 431 eliminated as unused. */ | |
| 432 if (TREE_CODE (t) == VAR_DECL) | |
| 433 { | |
| 434 if (data != NULL && bitmap_bit_p ((bitmap) data, DECL_UID (t))) | |
| 435 { | |
| 436 bitmap_clear_bit ((bitmap) data, DECL_UID (t)); | |
| 437 mark_all_vars_used (&DECL_INITIAL (t), data); | |
| 438 } | |
| 439 set_is_used (t); | |
| 440 } | |
| 441 | |
| 442 if (IS_TYPE_OR_DECL_P (t)) | |
| 443 *walk_subtrees = 0; | |
| 444 | |
| 445 return NULL; | |
| 446 } | |
| 447 | |
| 448 /* Mark the scope block SCOPE and its subblocks unused when they can be | |
| 449 possibly eliminated if dead. */ | |
| 450 | |
| 451 static void | |
| 452 mark_scope_block_unused (tree scope) | |
| 453 { | |
| 454 tree t; | |
| 455 TREE_USED (scope) = false; | |
| 456 if (!(*debug_hooks->ignore_block) (scope)) | |
| 457 TREE_USED (scope) = true; | |
| 458 for (t = BLOCK_SUBBLOCKS (scope); t ; t = BLOCK_CHAIN (t)) | |
| 459 mark_scope_block_unused (t); | |
| 460 } | |
| 461 | |
| 462 /* Look if the block is dead (by possibly eliminating its dead subblocks) | |
| 463 and return true if so. | |
| 464 Block is declared dead if: | |
| 465 1) No statements are associated with it. | |
| 466 2) Declares no live variables | |
| 467 3) All subblocks are dead | |
| 468 or there is precisely one subblocks and the block | |
| 469 has same abstract origin as outer block and declares | |
| 470 no variables, so it is pure wrapper. | |
| 471 When we are not outputting full debug info, we also eliminate dead variables | |
| 472 out of scope blocks to let them to be recycled by GGC and to save copying work | |
| 473 done by the inliner. */ | |
| 474 | |
| 475 static bool | |
| 476 remove_unused_scope_block_p (tree scope) | |
| 477 { | |
| 478 tree *t, *next; | |
| 479 bool unused = !TREE_USED (scope); | |
| 480 var_ann_t ann; | |
| 481 int nsubblocks = 0; | |
| 482 | |
| 483 for (t = &BLOCK_VARS (scope); *t; t = next) | |
| 484 { | |
| 485 next = &TREE_CHAIN (*t); | |
| 486 | |
| 487 /* Debug info of nested function refers to the block of the | |
| 488 function. We might stil call it even if all statements | |
| 489 of function it was nested into was elliminated. | |
| 490 | |
| 491 TODO: We can actually look into cgraph to see if function | |
| 492 will be output to file. */ | |
| 493 if (TREE_CODE (*t) == FUNCTION_DECL) | |
| 494 unused = false; | |
| 495 /* Remove everything we don't generate debug info for. */ | |
| 496 else if (DECL_IGNORED_P (*t)) | |
| 497 { | |
| 498 *t = TREE_CHAIN (*t); | |
| 499 next = t; | |
| 500 } | |
| 501 | |
| 502 /* When we are outputting debug info, we usually want to output | |
| 503 info about optimized-out variables in the scope blocks. | |
| 504 Exception are the scope blocks not containing any instructions | |
| 505 at all so user can't get into the scopes at first place. */ | |
| 506 else if ((ann = var_ann (*t)) != NULL | |
| 507 && ann->used) | |
| 508 unused = false; | |
| 509 | |
| 510 /* When we are not doing full debug info, we however can keep around | |
| 511 only the used variables for cfgexpand's memory packing saving quite | |
| 512 a lot of memory. | |
| 513 | |
| 514 For sake of -g3, we keep around those vars but we don't count this as | |
| 515 use of block, so innermost block with no used vars and no instructions | |
| 516 can be considered dead. We only want to keep around blocks user can | |
| 517 breakpoint into and ask about value of optimized out variables. | |
| 518 | |
| 519 Similarly we need to keep around types at least until all variables of | |
| 520 all nested blocks are gone. We track no information on whether given | |
| 521 type is used or not. */ | |
| 522 | |
| 523 else if (debug_info_level == DINFO_LEVEL_NORMAL | |
| 524 || debug_info_level == DINFO_LEVEL_VERBOSE | |
| 525 /* Removing declarations before inlining is going to affect | |
| 526 DECL_UID that in turn is going to affect hashtables and | |
| 527 code generation. */ | |
| 528 || !cfun->after_inlining) | |
| 529 ; | |
| 530 else | |
| 531 { | |
| 532 *t = TREE_CHAIN (*t); | |
| 533 next = t; | |
| 534 } | |
| 535 } | |
| 536 | |
| 537 for (t = &BLOCK_SUBBLOCKS (scope); *t ;) | |
| 538 if (remove_unused_scope_block_p (*t)) | |
| 539 { | |
| 540 if (BLOCK_SUBBLOCKS (*t)) | |
| 541 { | |
| 542 tree next = BLOCK_CHAIN (*t); | |
| 543 tree supercontext = BLOCK_SUPERCONTEXT (*t); | |
| 544 | |
| 545 *t = BLOCK_SUBBLOCKS (*t); | |
| 546 while (BLOCK_CHAIN (*t)) | |
| 547 { | |
| 548 BLOCK_SUPERCONTEXT (*t) = supercontext; | |
| 549 t = &BLOCK_CHAIN (*t); | |
| 550 } | |
| 551 BLOCK_CHAIN (*t) = next; | |
| 552 BLOCK_SUPERCONTEXT (*t) = supercontext; | |
| 553 t = &BLOCK_CHAIN (*t); | |
| 554 nsubblocks ++; | |
| 555 } | |
| 556 else | |
| 557 *t = BLOCK_CHAIN (*t); | |
| 558 } | |
| 559 else | |
| 560 { | |
| 561 t = &BLOCK_CHAIN (*t); | |
| 562 nsubblocks ++; | |
| 563 } | |
| 564 | |
| 565 | |
| 566 if (!unused) | |
| 567 ; | |
| 568 /* Outer scope is always used. */ | |
| 569 else if (!BLOCK_SUPERCONTEXT (scope) | |
| 570 || TREE_CODE (BLOCK_SUPERCONTEXT (scope)) == FUNCTION_DECL) | |
| 571 unused = false; | |
| 572 /* Innermost blocks with no live variables nor statements can be always | |
| 573 eliminated. */ | |
| 574 else if (!nsubblocks) | |
| 575 ; | |
| 576 /* If there are live subblocks and we still have some unused variables | |
| 577 or types declared, we must keep them. | |
| 578 Before inliing we must not depend on debug info verbosity to keep | |
| 579 DECL_UIDs stable. */ | |
| 580 else if (!cfun->after_inlining && BLOCK_VARS (scope)) | |
| 581 unused = false; | |
| 582 /* For terse debug info we can eliminate info on unused variables. */ | |
| 583 else if (debug_info_level == DINFO_LEVEL_NONE | |
| 584 || debug_info_level == DINFO_LEVEL_TERSE) | |
|
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585 { |
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586 /* Even for -g0/-g1 don't prune outer scopes from artificial |
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587 functions, otherwise diagnostics using tree_nonartificial_location |
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588 will not be emitted properly. */ |
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589 if (inlined_function_outer_scope_p (scope)) |
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590 { |
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591 tree ao = scope; |
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592 |
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593 while (ao |
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594 && TREE_CODE (ao) == BLOCK |
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595 && BLOCK_ABSTRACT_ORIGIN (ao) != ao) |
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596 ao = BLOCK_ABSTRACT_ORIGIN (ao); |
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597 if (ao |
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598 && TREE_CODE (ao) == FUNCTION_DECL |
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599 && DECL_DECLARED_INLINE_P (ao) |
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600 && lookup_attribute ("artificial", DECL_ATTRIBUTES (ao))) |
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601 unused = false; |
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602 } |
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603 } |
| 0 | 604 else if (BLOCK_VARS (scope) || BLOCK_NUM_NONLOCALIZED_VARS (scope)) |
| 605 unused = false; | |
| 606 /* See if this block is important for representation of inlined function. | |
| 607 Inlined functions are always represented by block with | |
| 608 block_ultimate_origin being set to FUNCTION_DECL and DECL_SOURCE_LOCATION | |
| 609 set... */ | |
| 610 else if (inlined_function_outer_scope_p (scope)) | |
| 611 unused = false; | |
| 612 else | |
| 613 /* Verfify that only blocks with source location set | |
| 614 are entry points to the inlined functions. */ | |
| 615 gcc_assert (BLOCK_SOURCE_LOCATION (scope) == UNKNOWN_LOCATION); | |
|
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616 |
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617 TREE_USED (scope) = !unused; |
| 0 | 618 return unused; |
| 619 } | |
| 620 | |
| 621 /* Mark all VAR_DECLS under *EXPR_P as used, so that they won't be | |
| 622 eliminated during the tree->rtl conversion process. */ | |
| 623 | |
| 624 static inline void | |
| 625 mark_all_vars_used (tree *expr_p, void *data) | |
| 626 { | |
| 627 walk_tree (expr_p, mark_all_vars_used_1, data, NULL); | |
| 628 } | |
| 629 | |
| 630 /* Dump scope blocks. */ | |
| 631 | |
| 632 static void | |
| 633 dump_scope_block (FILE *file, int indent, tree scope, int flags) | |
| 634 { | |
| 635 tree var, t; | |
| 636 unsigned int i; | |
| 637 | |
| 638 fprintf (file, "\n%*s{ Scope block #%i%s%s",indent, "" , BLOCK_NUMBER (scope), | |
| 639 TREE_USED (scope) ? "" : " (unused)", | |
| 640 BLOCK_ABSTRACT (scope) ? " (abstract)": ""); | |
| 641 if (BLOCK_SOURCE_LOCATION (scope) != UNKNOWN_LOCATION) | |
| 642 { | |
| 643 expanded_location s = expand_location (BLOCK_SOURCE_LOCATION (scope)); | |
| 644 fprintf (file, " %s:%i", s.file, s.line); | |
| 645 } | |
| 646 if (BLOCK_ABSTRACT_ORIGIN (scope)) | |
| 647 { | |
| 648 tree origin = block_ultimate_origin (scope); | |
| 649 if (origin) | |
| 650 { | |
| 651 fprintf (file, " Originating from :"); | |
| 652 if (DECL_P (origin)) | |
| 653 print_generic_decl (file, origin, flags); | |
| 654 else | |
| 655 fprintf (file, "#%i", BLOCK_NUMBER (origin)); | |
| 656 } | |
| 657 } | |
| 658 fprintf (file, " \n"); | |
| 659 for (var = BLOCK_VARS (scope); var; var = TREE_CHAIN (var)) | |
| 660 { | |
| 661 bool used = false; | |
| 662 var_ann_t ann; | |
| 663 | |
| 664 if ((ann = var_ann (var)) | |
| 665 && ann->used) | |
| 666 used = true; | |
| 667 | |
| 668 fprintf (file, "%*s",indent, ""); | |
| 669 print_generic_decl (file, var, flags); | |
| 670 fprintf (file, "%s\n", used ? "" : " (unused)"); | |
| 671 } | |
| 672 for (i = 0; i < BLOCK_NUM_NONLOCALIZED_VARS (scope); i++) | |
| 673 { | |
| 674 fprintf (file, "%*s",indent, ""); | |
| 675 print_generic_decl (file, BLOCK_NONLOCALIZED_VAR (scope, i), | |
| 676 flags); | |
| 677 fprintf (file, " (nonlocalized)\n"); | |
| 678 } | |
| 679 for (t = BLOCK_SUBBLOCKS (scope); t ; t = BLOCK_CHAIN (t)) | |
| 680 dump_scope_block (file, indent + 2, t, flags); | |
| 681 fprintf (file, "\n%*s}\n",indent, ""); | |
| 682 } | |
| 683 | |
| 684 void | |
| 685 dump_scope_blocks (FILE *file, int flags) | |
| 686 { | |
| 687 dump_scope_block (file, 0, DECL_INITIAL (current_function_decl), flags); | |
| 688 } | |
| 689 | |
| 690 /* Remove local variables that are not referenced in the IL. */ | |
| 691 | |
| 692 void | |
| 693 remove_unused_locals (void) | |
| 694 { | |
| 695 basic_block bb; | |
| 696 tree t, *cell; | |
| 697 referenced_var_iterator rvi; | |
| 698 var_ann_t ann; | |
| 699 bitmap global_unused_vars = NULL; | |
| 700 | |
|
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701 /* Removing declarations from lexical blocks when not optimizing is |
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702 not only a waste of time, it actually causes differences in stack |
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703 layout. */ |
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704 if (!optimize) |
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705 return; |
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706 |
| 0 | 707 mark_scope_block_unused (DECL_INITIAL (current_function_decl)); |
| 708 | |
| 709 /* Assume all locals are unused. */ | |
| 710 FOR_EACH_REFERENCED_VAR (t, rvi) | |
| 711 var_ann (t)->used = false; | |
| 712 | |
| 713 /* Walk the CFG marking all referenced symbols. */ | |
| 714 FOR_EACH_BB (bb) | |
| 715 { | |
| 716 gimple_stmt_iterator gsi; | |
| 717 size_t i; | |
| 718 edge_iterator ei; | |
| 719 edge e; | |
| 720 | |
| 721 /* Walk the statements. */ | |
| 722 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 723 { | |
| 724 gimple stmt = gsi_stmt (gsi); | |
| 725 tree b = gimple_block (stmt); | |
| 726 | |
| 727 if (b) | |
| 728 TREE_USED (b) = true; | |
| 729 | |
| 730 for (i = 0; i < gimple_num_ops (stmt); i++) | |
| 731 mark_all_vars_used (gimple_op_ptr (gsi_stmt (gsi), i), NULL); | |
| 732 } | |
| 733 | |
| 734 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 735 { | |
| 736 use_operand_p arg_p; | |
| 737 ssa_op_iter i; | |
| 738 tree def; | |
| 739 gimple phi = gsi_stmt (gsi); | |
| 740 | |
| 741 /* No point processing globals. */ | |
| 742 if (is_global_var (SSA_NAME_VAR (gimple_phi_result (phi)))) | |
| 743 continue; | |
| 744 | |
| 745 def = gimple_phi_result (phi); | |
| 746 mark_all_vars_used (&def, NULL); | |
| 747 | |
| 748 FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_ALL_USES) | |
| 749 { | |
| 750 tree arg = USE_FROM_PTR (arg_p); | |
| 751 mark_all_vars_used (&arg, NULL); | |
| 752 } | |
| 753 } | |
| 754 | |
| 755 FOR_EACH_EDGE (e, ei, bb->succs) | |
| 756 if (e->goto_locus) | |
| 757 TREE_USED (e->goto_block) = true; | |
| 758 } | |
| 759 | |
| 760 cfun->has_local_explicit_reg_vars = false; | |
| 761 | |
| 762 /* Remove unmarked local vars from local_decls. */ | |
| 763 for (cell = &cfun->local_decls; *cell; ) | |
| 764 { | |
| 765 tree var = TREE_VALUE (*cell); | |
| 766 | |
| 767 if (TREE_CODE (var) != FUNCTION_DECL | |
| 768 && (!(ann = var_ann (var)) | |
|
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769 || !ann->used)) |
| 0 | 770 { |
| 771 if (is_global_var (var)) | |
| 772 { | |
| 773 if (global_unused_vars == NULL) | |
| 774 global_unused_vars = BITMAP_ALLOC (NULL); | |
| 775 bitmap_set_bit (global_unused_vars, DECL_UID (var)); | |
| 776 } | |
| 777 else | |
| 778 { | |
| 779 *cell = TREE_CHAIN (*cell); | |
| 780 continue; | |
| 781 } | |
| 782 } | |
| 783 else if (TREE_CODE (var) == VAR_DECL | |
| 784 && DECL_HARD_REGISTER (var) | |
| 785 && !is_global_var (var)) | |
| 786 cfun->has_local_explicit_reg_vars = true; | |
| 787 cell = &TREE_CHAIN (*cell); | |
| 788 } | |
| 789 | |
| 790 /* Remove unmarked global vars from local_decls. */ | |
| 791 if (global_unused_vars != NULL) | |
| 792 { | |
| 793 for (t = cfun->local_decls; t; t = TREE_CHAIN (t)) | |
| 794 { | |
| 795 tree var = TREE_VALUE (t); | |
| 796 | |
| 797 if (TREE_CODE (var) == VAR_DECL | |
| 798 && is_global_var (var) | |
| 799 && (ann = var_ann (var)) != NULL | |
| 800 && ann->used) | |
| 801 mark_all_vars_used (&DECL_INITIAL (var), global_unused_vars); | |
| 802 } | |
| 803 | |
| 804 for (cell = &cfun->local_decls; *cell; ) | |
| 805 { | |
| 806 tree var = TREE_VALUE (*cell); | |
| 807 | |
| 808 if (TREE_CODE (var) == VAR_DECL | |
| 809 && is_global_var (var) | |
| 810 && bitmap_bit_p (global_unused_vars, DECL_UID (var))) | |
| 811 *cell = TREE_CHAIN (*cell); | |
| 812 else | |
| 813 cell = &TREE_CHAIN (*cell); | |
| 814 } | |
| 815 BITMAP_FREE (global_unused_vars); | |
| 816 } | |
| 817 | |
| 818 /* Remove unused variables from REFERENCED_VARs. As a special | |
| 819 exception keep the variables that are believed to be aliased. | |
| 820 Those can't be easily removed from the alias sets and operand | |
| 821 caches. They will be removed shortly after the next may_alias | |
| 822 pass is performed. */ | |
| 823 FOR_EACH_REFERENCED_VAR (t, rvi) | |
| 824 if (!is_global_var (t) | |
| 825 && !MTAG_P (t) | |
| 826 && TREE_CODE (t) != PARM_DECL | |
| 827 && TREE_CODE (t) != RESULT_DECL | |
| 828 && !(ann = var_ann (t))->used | |
| 829 && !ann->symbol_mem_tag | |
|
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830 && !TREE_ADDRESSABLE (t)) |
| 0 | 831 remove_referenced_var (t); |
| 832 remove_unused_scope_block_p (DECL_INITIAL (current_function_decl)); | |
| 833 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 834 { | |
| 835 fprintf (dump_file, "Scope blocks after cleanups:\n"); | |
| 836 dump_scope_blocks (dump_file, dump_flags); | |
| 837 } | |
| 838 } | |
| 839 | |
| 840 | |
| 841 /* Allocate and return a new live range information object base on MAP. */ | |
| 842 | |
| 843 static tree_live_info_p | |
| 844 new_tree_live_info (var_map map) | |
| 845 { | |
| 846 tree_live_info_p live; | |
| 847 unsigned x; | |
| 848 | |
| 849 live = (tree_live_info_p) xmalloc (sizeof (struct tree_live_info_d)); | |
| 850 live->map = map; | |
| 851 live->num_blocks = last_basic_block; | |
| 852 | |
| 853 live->livein = (bitmap *)xmalloc (last_basic_block * sizeof (bitmap)); | |
| 854 for (x = 0; x < (unsigned)last_basic_block; x++) | |
| 855 live->livein[x] = BITMAP_ALLOC (NULL); | |
| 856 | |
| 857 live->liveout = (bitmap *)xmalloc (last_basic_block * sizeof (bitmap)); | |
| 858 for (x = 0; x < (unsigned)last_basic_block; x++) | |
| 859 live->liveout[x] = BITMAP_ALLOC (NULL); | |
| 860 | |
| 861 live->work_stack = XNEWVEC (int, last_basic_block); | |
| 862 live->stack_top = live->work_stack; | |
| 863 | |
| 864 live->global = BITMAP_ALLOC (NULL); | |
| 865 return live; | |
| 866 } | |
| 867 | |
| 868 | |
| 869 /* Free storage for live range info object LIVE. */ | |
| 870 | |
| 871 void | |
| 872 delete_tree_live_info (tree_live_info_p live) | |
| 873 { | |
| 874 int x; | |
| 875 | |
| 876 BITMAP_FREE (live->global); | |
| 877 free (live->work_stack); | |
| 878 | |
| 879 for (x = live->num_blocks - 1; x >= 0; x--) | |
| 880 BITMAP_FREE (live->liveout[x]); | |
| 881 free (live->liveout); | |
| 882 | |
| 883 for (x = live->num_blocks - 1; x >= 0; x--) | |
| 884 BITMAP_FREE (live->livein[x]); | |
| 885 free (live->livein); | |
| 886 | |
| 887 free (live); | |
| 888 } | |
| 889 | |
| 890 | |
| 891 /* Visit basic block BB and propagate any required live on entry bits from | |
| 892 LIVE into the predecessors. VISITED is the bitmap of visited blocks. | |
| 893 TMP is a temporary work bitmap which is passed in to avoid reallocating | |
| 894 it each time. */ | |
| 895 | |
| 896 static void | |
| 897 loe_visit_block (tree_live_info_p live, basic_block bb, sbitmap visited, | |
| 898 bitmap tmp) | |
| 899 { | |
| 900 edge e; | |
| 901 bool change; | |
| 902 edge_iterator ei; | |
| 903 basic_block pred_bb; | |
| 904 bitmap loe; | |
| 905 gcc_assert (!TEST_BIT (visited, bb->index)); | |
| 906 | |
| 907 SET_BIT (visited, bb->index); | |
| 908 loe = live_on_entry (live, bb); | |
| 909 | |
| 910 FOR_EACH_EDGE (e, ei, bb->preds) | |
| 911 { | |
| 912 pred_bb = e->src; | |
| 913 if (pred_bb == ENTRY_BLOCK_PTR) | |
| 914 continue; | |
| 915 /* TMP is variables live-on-entry from BB that aren't defined in the | |
| 916 predecessor block. This should be the live on entry vars to pred. | |
| 917 Note that liveout is the DEFs in a block while live on entry is | |
| 918 being calculated. */ | |
| 919 bitmap_and_compl (tmp, loe, live->liveout[pred_bb->index]); | |
| 920 | |
| 921 /* Add these bits to live-on-entry for the pred. if there are any | |
| 922 changes, and pred_bb has been visited already, add it to the | |
| 923 revisit stack. */ | |
| 924 change = bitmap_ior_into (live_on_entry (live, pred_bb), tmp); | |
| 925 if (TEST_BIT (visited, pred_bb->index) && change) | |
| 926 { | |
| 927 RESET_BIT (visited, pred_bb->index); | |
| 928 *(live->stack_top)++ = pred_bb->index; | |
| 929 } | |
| 930 } | |
| 931 } | |
| 932 | |
| 933 | |
| 934 /* Using LIVE, fill in all the live-on-entry blocks between the defs and uses | |
| 935 of all the variables. */ | |
| 936 | |
| 937 static void | |
| 938 live_worklist (tree_live_info_p live) | |
| 939 { | |
| 940 unsigned b; | |
| 941 basic_block bb; | |
| 942 sbitmap visited = sbitmap_alloc (last_basic_block + 1); | |
| 943 bitmap tmp = BITMAP_ALLOC (NULL); | |
| 944 | |
| 945 sbitmap_zero (visited); | |
| 946 | |
| 947 /* Visit all the blocks in reverse order and propagate live on entry values | |
| 948 into the predecessors blocks. */ | |
| 949 FOR_EACH_BB_REVERSE (bb) | |
| 950 loe_visit_block (live, bb, visited, tmp); | |
| 951 | |
| 952 /* Process any blocks which require further iteration. */ | |
| 953 while (live->stack_top != live->work_stack) | |
| 954 { | |
| 955 b = *--(live->stack_top); | |
| 956 loe_visit_block (live, BASIC_BLOCK (b), visited, tmp); | |
| 957 } | |
| 958 | |
| 959 BITMAP_FREE (tmp); | |
| 960 sbitmap_free (visited); | |
| 961 } | |
| 962 | |
| 963 | |
| 964 /* Calculate the initial live on entry vector for SSA_NAME using immediate_use | |
| 965 links. Set the live on entry fields in LIVE. Def's are marked temporarily | |
| 966 in the liveout vector. */ | |
| 967 | |
| 968 static void | |
| 969 set_var_live_on_entry (tree ssa_name, tree_live_info_p live) | |
| 970 { | |
| 971 int p; | |
| 972 gimple stmt; | |
| 973 use_operand_p use; | |
| 974 basic_block def_bb = NULL; | |
| 975 imm_use_iterator imm_iter; | |
| 976 bool global = false; | |
| 977 | |
| 978 p = var_to_partition (live->map, ssa_name); | |
| 979 if (p == NO_PARTITION) | |
| 980 return; | |
| 981 | |
| 982 stmt = SSA_NAME_DEF_STMT (ssa_name); | |
| 983 if (stmt) | |
| 984 { | |
| 985 def_bb = gimple_bb (stmt); | |
| 986 /* Mark defs in liveout bitmap temporarily. */ | |
| 987 if (def_bb) | |
| 988 bitmap_set_bit (live->liveout[def_bb->index], p); | |
| 989 } | |
| 990 else | |
| 991 def_bb = ENTRY_BLOCK_PTR; | |
| 992 | |
| 993 /* Visit each use of SSA_NAME and if it isn't in the same block as the def, | |
| 994 add it to the list of live on entry blocks. */ | |
| 995 FOR_EACH_IMM_USE_FAST (use, imm_iter, ssa_name) | |
| 996 { | |
| 997 gimple use_stmt = USE_STMT (use); | |
| 998 basic_block add_block = NULL; | |
| 999 | |
| 1000 if (gimple_code (use_stmt) == GIMPLE_PHI) | |
| 1001 { | |
| 1002 /* Uses in PHI's are considered to be live at exit of the SRC block | |
| 1003 as this is where a copy would be inserted. Check to see if it is | |
| 1004 defined in that block, or whether its live on entry. */ | |
| 1005 int index = PHI_ARG_INDEX_FROM_USE (use); | |
| 1006 edge e = gimple_phi_arg_edge (use_stmt, index); | |
| 1007 if (e->src != ENTRY_BLOCK_PTR) | |
| 1008 { | |
| 1009 if (e->src != def_bb) | |
| 1010 add_block = e->src; | |
| 1011 } | |
| 1012 } | |
| 1013 else | |
| 1014 { | |
| 1015 /* If its not defined in this block, its live on entry. */ | |
| 1016 basic_block use_bb = gimple_bb (use_stmt); | |
| 1017 if (use_bb != def_bb) | |
| 1018 add_block = use_bb; | |
| 1019 } | |
| 1020 | |
| 1021 /* If there was a live on entry use, set the bit. */ | |
| 1022 if (add_block) | |
| 1023 { | |
| 1024 global = true; | |
| 1025 bitmap_set_bit (live->livein[add_block->index], p); | |
| 1026 } | |
| 1027 } | |
| 1028 | |
| 1029 /* If SSA_NAME is live on entry to at least one block, fill in all the live | |
| 1030 on entry blocks between the def and all the uses. */ | |
| 1031 if (global) | |
| 1032 bitmap_set_bit (live->global, p); | |
| 1033 } | |
| 1034 | |
| 1035 | |
| 1036 /* Calculate the live on exit vectors based on the entry info in LIVEINFO. */ | |
| 1037 | |
| 1038 void | |
| 1039 calculate_live_on_exit (tree_live_info_p liveinfo) | |
| 1040 { | |
| 1041 basic_block bb; | |
| 1042 edge e; | |
| 1043 edge_iterator ei; | |
| 1044 | |
| 1045 /* live on entry calculations used liveout vectors for defs, clear them. */ | |
| 1046 FOR_EACH_BB (bb) | |
| 1047 bitmap_clear (liveinfo->liveout[bb->index]); | |
| 1048 | |
| 1049 /* Set all the live-on-exit bits for uses in PHIs. */ | |
| 1050 FOR_EACH_BB (bb) | |
| 1051 { | |
| 1052 gimple_stmt_iterator gsi; | |
| 1053 size_t i; | |
| 1054 | |
| 1055 /* Mark the PHI arguments which are live on exit to the pred block. */ | |
| 1056 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
| 1057 { | |
| 1058 gimple phi = gsi_stmt (gsi); | |
| 1059 for (i = 0; i < gimple_phi_num_args (phi); i++) | |
| 1060 { | |
| 1061 tree t = PHI_ARG_DEF (phi, i); | |
| 1062 int p; | |
| 1063 | |
| 1064 if (TREE_CODE (t) != SSA_NAME) | |
| 1065 continue; | |
| 1066 | |
| 1067 p = var_to_partition (liveinfo->map, t); | |
| 1068 if (p == NO_PARTITION) | |
| 1069 continue; | |
| 1070 e = gimple_phi_arg_edge (phi, i); | |
| 1071 if (e->src != ENTRY_BLOCK_PTR) | |
| 1072 bitmap_set_bit (liveinfo->liveout[e->src->index], p); | |
| 1073 } | |
| 1074 } | |
| 1075 | |
| 1076 /* Add each successors live on entry to this bock live on exit. */ | |
| 1077 FOR_EACH_EDGE (e, ei, bb->succs) | |
| 1078 if (e->dest != EXIT_BLOCK_PTR) | |
| 1079 bitmap_ior_into (liveinfo->liveout[bb->index], | |
| 1080 live_on_entry (liveinfo, e->dest)); | |
| 1081 } | |
| 1082 } | |
| 1083 | |
| 1084 | |
| 1085 /* Given partition map MAP, calculate all the live on entry bitmaps for | |
| 1086 each partition. Return a new live info object. */ | |
| 1087 | |
| 1088 tree_live_info_p | |
| 1089 calculate_live_ranges (var_map map) | |
| 1090 { | |
| 1091 tree var; | |
| 1092 unsigned i; | |
| 1093 tree_live_info_p live; | |
| 1094 | |
| 1095 live = new_tree_live_info (map); | |
| 1096 for (i = 0; i < num_var_partitions (map); i++) | |
| 1097 { | |
| 1098 var = partition_to_var (map, i); | |
| 1099 if (var != NULL_TREE) | |
| 1100 set_var_live_on_entry (var, live); | |
| 1101 } | |
| 1102 | |
| 1103 live_worklist (live); | |
| 1104 | |
| 1105 #ifdef ENABLE_CHECKING | |
| 1106 verify_live_on_entry (live); | |
| 1107 #endif | |
| 1108 | |
| 1109 calculate_live_on_exit (live); | |
| 1110 return live; | |
| 1111 } | |
| 1112 | |
| 1113 | |
| 1114 /* Output partition map MAP to file F. */ | |
| 1115 | |
| 1116 void | |
| 1117 dump_var_map (FILE *f, var_map map) | |
| 1118 { | |
| 1119 int t; | |
| 1120 unsigned x, y; | |
| 1121 int p; | |
| 1122 | |
| 1123 fprintf (f, "\nPartition map \n\n"); | |
| 1124 | |
| 1125 for (x = 0; x < map->num_partitions; x++) | |
| 1126 { | |
| 1127 if (map->view_to_partition != NULL) | |
| 1128 p = map->view_to_partition[x]; | |
| 1129 else | |
| 1130 p = x; | |
| 1131 | |
| 1132 if (map->partition_to_var[p] == NULL_TREE) | |
| 1133 continue; | |
| 1134 | |
| 1135 t = 0; | |
| 1136 for (y = 1; y < num_ssa_names; y++) | |
| 1137 { | |
| 1138 p = partition_find (map->var_partition, y); | |
| 1139 if (map->partition_to_view) | |
| 1140 p = map->partition_to_view[p]; | |
| 1141 if (p == (int)x) | |
| 1142 { | |
| 1143 if (t++ == 0) | |
| 1144 { | |
| 1145 fprintf(f, "Partition %d (", x); | |
| 1146 print_generic_expr (f, partition_to_var (map, p), TDF_SLIM); | |
| 1147 fprintf (f, " - "); | |
| 1148 } | |
| 1149 fprintf (f, "%d ", y); | |
| 1150 } | |
| 1151 } | |
| 1152 if (t != 0) | |
| 1153 fprintf (f, ")\n"); | |
| 1154 } | |
| 1155 fprintf (f, "\n"); | |
| 1156 } | |
| 1157 | |
| 1158 | |
| 1159 /* Output live range info LIVE to file F, controlled by FLAG. */ | |
| 1160 | |
| 1161 void | |
| 1162 dump_live_info (FILE *f, tree_live_info_p live, int flag) | |
| 1163 { | |
| 1164 basic_block bb; | |
| 1165 unsigned i; | |
| 1166 var_map map = live->map; | |
| 1167 bitmap_iterator bi; | |
| 1168 | |
| 1169 if ((flag & LIVEDUMP_ENTRY) && live->livein) | |
| 1170 { | |
| 1171 FOR_EACH_BB (bb) | |
| 1172 { | |
| 1173 fprintf (f, "\nLive on entry to BB%d : ", bb->index); | |
| 1174 EXECUTE_IF_SET_IN_BITMAP (live->livein[bb->index], 0, i, bi) | |
| 1175 { | |
| 1176 print_generic_expr (f, partition_to_var (map, i), TDF_SLIM); | |
| 1177 fprintf (f, " "); | |
| 1178 } | |
| 1179 fprintf (f, "\n"); | |
| 1180 } | |
| 1181 } | |
| 1182 | |
| 1183 if ((flag & LIVEDUMP_EXIT) && live->liveout) | |
| 1184 { | |
| 1185 FOR_EACH_BB (bb) | |
| 1186 { | |
| 1187 fprintf (f, "\nLive on exit from BB%d : ", bb->index); | |
| 1188 EXECUTE_IF_SET_IN_BITMAP (live->liveout[bb->index], 0, i, bi) | |
| 1189 { | |
| 1190 print_generic_expr (f, partition_to_var (map, i), TDF_SLIM); | |
| 1191 fprintf (f, " "); | |
| 1192 } | |
| 1193 fprintf (f, "\n"); | |
| 1194 } | |
| 1195 } | |
| 1196 } | |
| 1197 | |
| 1198 | |
| 1199 #ifdef ENABLE_CHECKING | |
| 1200 /* Verify that SSA_VAR is a non-virtual SSA_NAME. */ | |
| 1201 | |
| 1202 void | |
| 1203 register_ssa_partition_check (tree ssa_var) | |
| 1204 { | |
| 1205 gcc_assert (TREE_CODE (ssa_var) == SSA_NAME); | |
| 1206 if (!is_gimple_reg (SSA_NAME_VAR (ssa_var))) | |
| 1207 { | |
| 1208 fprintf (stderr, "Illegally registering a virtual SSA name :"); | |
| 1209 print_generic_expr (stderr, ssa_var, TDF_SLIM); | |
| 1210 fprintf (stderr, " in the SSA->Normal phase.\n"); | |
| 1211 internal_error ("SSA corruption"); | |
| 1212 } | |
| 1213 } | |
| 1214 | |
| 1215 | |
| 1216 /* Verify that the info in LIVE matches the current cfg. */ | |
| 1217 | |
| 1218 static void | |
| 1219 verify_live_on_entry (tree_live_info_p live) | |
| 1220 { | |
| 1221 unsigned i; | |
| 1222 tree var; | |
| 1223 gimple stmt; | |
| 1224 basic_block bb; | |
| 1225 edge e; | |
| 1226 int num; | |
| 1227 edge_iterator ei; | |
| 1228 var_map map = live->map; | |
| 1229 | |
| 1230 /* Check for live on entry partitions and report those with a DEF in | |
| 1231 the program. This will typically mean an optimization has done | |
| 1232 something wrong. */ | |
| 1233 bb = ENTRY_BLOCK_PTR; | |
| 1234 num = 0; | |
| 1235 FOR_EACH_EDGE (e, ei, bb->succs) | |
| 1236 { | |
| 1237 int entry_block = e->dest->index; | |
| 1238 if (e->dest == EXIT_BLOCK_PTR) | |
| 1239 continue; | |
| 1240 for (i = 0; i < (unsigned)num_var_partitions (map); i++) | |
| 1241 { | |
| 1242 basic_block tmp; | |
| 1243 tree d; | |
| 1244 bitmap loe; | |
| 1245 var = partition_to_var (map, i); | |
| 1246 stmt = SSA_NAME_DEF_STMT (var); | |
| 1247 tmp = gimple_bb (stmt); | |
| 1248 d = gimple_default_def (cfun, SSA_NAME_VAR (var)); | |
| 1249 | |
| 1250 loe = live_on_entry (live, e->dest); | |
| 1251 if (loe && bitmap_bit_p (loe, i)) | |
| 1252 { | |
| 1253 if (!gimple_nop_p (stmt)) | |
| 1254 { | |
| 1255 num++; | |
| 1256 print_generic_expr (stderr, var, TDF_SLIM); | |
| 1257 fprintf (stderr, " is defined "); | |
| 1258 if (tmp) | |
| 1259 fprintf (stderr, " in BB%d, ", tmp->index); | |
| 1260 fprintf (stderr, "by:\n"); | |
| 1261 print_gimple_stmt (stderr, stmt, 0, TDF_SLIM); | |
| 1262 fprintf (stderr, "\nIt is also live-on-entry to entry BB %d", | |
| 1263 entry_block); | |
| 1264 fprintf (stderr, " So it appears to have multiple defs.\n"); | |
| 1265 } | |
| 1266 else | |
| 1267 { | |
| 1268 if (d != var) | |
| 1269 { | |
| 1270 num++; | |
| 1271 print_generic_expr (stderr, var, TDF_SLIM); | |
| 1272 fprintf (stderr, " is live-on-entry to BB%d ", | |
| 1273 entry_block); | |
| 1274 if (d) | |
| 1275 { | |
| 1276 fprintf (stderr, " but is not the default def of "); | |
| 1277 print_generic_expr (stderr, d, TDF_SLIM); | |
| 1278 fprintf (stderr, "\n"); | |
| 1279 } | |
| 1280 else | |
| 1281 fprintf (stderr, " and there is no default def.\n"); | |
| 1282 } | |
| 1283 } | |
| 1284 } | |
| 1285 else | |
| 1286 if (d == var) | |
| 1287 { | |
| 1288 /* The only way this var shouldn't be marked live on entry is | |
| 1289 if it occurs in a PHI argument of the block. */ | |
| 1290 size_t z; | |
| 1291 bool ok = false; | |
| 1292 gimple_stmt_iterator gsi; | |
| 1293 for (gsi = gsi_start_phis (e->dest); | |
| 1294 !gsi_end_p (gsi) && !ok; | |
| 1295 gsi_next (&gsi)) | |
| 1296 { | |
| 1297 gimple phi = gsi_stmt (gsi); | |
| 1298 for (z = 0; z < gimple_phi_num_args (phi); z++) | |
| 1299 if (var == gimple_phi_arg_def (phi, z)) | |
| 1300 { | |
| 1301 ok = true; | |
| 1302 break; | |
| 1303 } | |
| 1304 } | |
| 1305 if (ok) | |
| 1306 continue; | |
| 1307 num++; | |
| 1308 print_generic_expr (stderr, var, TDF_SLIM); | |
| 1309 fprintf (stderr, " is not marked live-on-entry to entry BB%d ", | |
| 1310 entry_block); | |
| 1311 fprintf (stderr, "but it is a default def so it should be.\n"); | |
| 1312 } | |
| 1313 } | |
| 1314 } | |
| 1315 gcc_assert (num <= 0); | |
| 1316 } | |
| 1317 #endif |