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Commit | Line | Data |
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6de9cd9a | 1 | /* Rewrite a program in Normal form into SSA. |
c47987fa | 2 | Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010 |
9dcd6f09 | 3 | Free Software Foundation, Inc. |
6de9cd9a DN |
4 | Contributed by Diego Novillo <dnovillo@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 | |
9dcd6f09 | 10 | the Free Software Foundation; either version 3, or (at your option) |
6de9cd9a DN |
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 | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
6de9cd9a DN |
21 | |
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
25 | #include "tm.h" | |
26 | #include "tree.h" | |
27 | #include "flags.h" | |
6de9cd9a DN |
28 | #include "tm_p.h" |
29 | #include "langhooks.h" | |
6de9cd9a DN |
30 | #include "basic-block.h" |
31 | #include "output.h" | |
6de9cd9a | 32 | #include "function.h" |
cf835838 JM |
33 | #include "tree-pretty-print.h" |
34 | #include "gimple-pretty-print.h" | |
6de9cd9a DN |
35 | #include "bitmap.h" |
36 | #include "tree-flow.h" | |
726a989a | 37 | #include "gimple.h" |
6de9cd9a | 38 | #include "tree-inline.h" |
6de9cd9a | 39 | #include "timevar.h" |
6de9cd9a DN |
40 | #include "hashtab.h" |
41 | #include "tree-dump.h" | |
42 | #include "tree-pass.h" | |
43 | #include "cfgloop.h" | |
44 | #include "domwalk.h" | |
84d65814 | 45 | #include "params.h" |
e3df376d | 46 | #include "vecprim.h" |
6de9cd9a | 47 | |
726a989a | 48 | |
6de9cd9a DN |
49 | /* This file builds the SSA form for a function as described in: |
50 | R. Cytron, J. Ferrante, B. Rosen, M. Wegman, and K. Zadeck. Efficiently | |
51 | Computing Static Single Assignment Form and the Control Dependence | |
52 | Graph. ACM Transactions on Programming Languages and Systems, | |
53 | 13(4):451-490, October 1991. */ | |
54 | ||
6de9cd9a DN |
55 | /* Structure to map a variable VAR to the set of blocks that contain |
56 | definitions for VAR. */ | |
57 | struct def_blocks_d | |
58 | { | |
59 | /* The variable. */ | |
60 | tree var; | |
61 | ||
62 | /* Blocks that contain definitions of VAR. Bit I will be set if the | |
63 | Ith block contains a definition of VAR. */ | |
64 | bitmap def_blocks; | |
65 | ||
7256233c | 66 | /* Blocks that contain a PHI node for VAR. */ |
5f240ec4 ZD |
67 | bitmap phi_blocks; |
68 | ||
6de9cd9a DN |
69 | /* Blocks where VAR is live-on-entry. Similar semantics as |
70 | DEF_BLOCKS. */ | |
71 | bitmap livein_blocks; | |
72 | }; | |
73 | ||
7256233c | 74 | |
6de9cd9a DN |
75 | /* Each entry in DEF_BLOCKS contains an element of type STRUCT |
76 | DEF_BLOCKS_D, mapping a variable VAR to a bitmap describing all the | |
77 | basic blocks where VAR is defined (assigned a new value). It also | |
78 | contains a bitmap of all the blocks where VAR is live-on-entry | |
79 | (i.e., there is a use of VAR in block B without a preceding | |
80 | definition in B). The live-on-entry information is used when | |
81 | computing PHI pruning heuristics. */ | |
82 | static htab_t def_blocks; | |
83 | ||
9fae925b | 84 | /* Stack of trees used to restore the global currdefs to its original |
0bca51f0 DN |
85 | state after completing rewriting of a block and its dominator |
86 | children. Its elements have the following properties: | |
9fae925b | 87 | |
38635499 DN |
88 | - An SSA_NAME (N) indicates that the current definition of the |
89 | underlying variable should be set to the given SSA_NAME. If the | |
90 | symbol associated with the SSA_NAME is not a GIMPLE register, the | |
91 | next slot in the stack must be a _DECL node (SYM). In this case, | |
92 | the name N in the previous slot is the current reaching | |
93 | definition for SYM. | |
9fae925b | 94 | |
0bca51f0 DN |
95 | - A _DECL node indicates that the underlying variable has no |
96 | current definition. | |
7256233c | 97 | |
38635499 | 98 | - A NULL node at the top entry is used to mark the last slot |
0bca51f0 | 99 | associated with the current block. */ |
d4e6fecb | 100 | static VEC(tree,heap) *block_defs_stack; |
3a2e4b46 | 101 | |
726a989a | 102 | |
0bca51f0 DN |
103 | /* Set of existing SSA names being replaced by update_ssa. */ |
104 | static sbitmap old_ssa_names; | |
105 | ||
106 | /* Set of new SSA names being added by update_ssa. Note that both | |
107 | NEW_SSA_NAMES and OLD_SSA_NAMES are dense bitmaps because most of | |
108 | the operations done on them are presence tests. */ | |
109 | static sbitmap new_ssa_names; | |
110 | ||
ccf5c864 | 111 | sbitmap interesting_blocks; |
726a989a | 112 | |
0bca51f0 DN |
113 | /* Set of SSA names that have been marked to be released after they |
114 | were registered in the replacement table. They will be finally | |
115 | released after we finish updating the SSA web. */ | |
116 | static bitmap names_to_release; | |
117 | ||
726a989a | 118 | static VEC(gimple_vec, heap) *phis_to_rewrite; |
2ce79879 ZD |
119 | |
120 | /* The bitmap of non-NULL elements of PHIS_TO_REWRITE. */ | |
2ce79879 ZD |
121 | static bitmap blocks_with_phis_to_rewrite; |
122 | ||
0bca51f0 DN |
123 | /* Growth factor for NEW_SSA_NAMES and OLD_SSA_NAMES. These sets need |
124 | to grow as the callers to register_new_name_mapping will typically | |
125 | create new names on the fly. FIXME. Currently set to 1/3 to avoid | |
126 | frequent reallocations but still need to find a reasonable growth | |
127 | strategy. */ | |
128 | #define NAME_SETS_GROWTH_FACTOR (MAX (3, num_ssa_names / 3)) | |
129 | ||
130 | /* Tuple used to represent replacement mappings. */ | |
131 | struct repl_map_d | |
132 | { | |
133 | tree name; | |
134 | bitmap set; | |
135 | }; | |
136 | ||
726a989a | 137 | |
0bca51f0 DN |
138 | /* NEW -> OLD_SET replacement table. If we are replacing several |
139 | existing SSA names O_1, O_2, ..., O_j with a new name N_i, | |
140 | then REPL_TBL[N_i] = { O_1, O_2, ..., O_j }. */ | |
141 | static htab_t repl_tbl; | |
142 | ||
5006671f RG |
143 | /* The function the SSA updating data structures have been initialized for. |
144 | NULL if they need to be initialized by register_new_name_mapping. */ | |
145 | static struct function *update_ssa_initialized_fn = NULL; | |
0bca51f0 | 146 | |
84d65814 DN |
147 | /* Statistics kept by update_ssa to use in the virtual mapping |
148 | heuristic. If the number of virtual mappings is beyond certain | |
149 | threshold, the updater will switch from using the mappings into | |
150 | renaming the virtual symbols from scratch. In some cases, the | |
151 | large number of name mappings for virtual names causes significant | |
152 | slowdowns in the PHI insertion code. */ | |
153 | struct update_ssa_stats_d | |
154 | { | |
155 | unsigned num_virtual_mappings; | |
156 | unsigned num_total_mappings; | |
157 | bitmap virtual_symbols; | |
158 | unsigned num_virtual_symbols; | |
159 | }; | |
160 | static struct update_ssa_stats_d update_ssa_stats; | |
0bca51f0 | 161 | |
6de9cd9a DN |
162 | /* Global data to attach to the main dominator walk structure. */ |
163 | struct mark_def_sites_global_data | |
164 | { | |
0bca51f0 DN |
165 | /* This bitmap contains the variables which are set before they |
166 | are used in a basic block. */ | |
7d793e36 | 167 | bitmap kills; |
6de9cd9a DN |
168 | }; |
169 | ||
5f240ec4 | 170 | |
0bca51f0 | 171 | /* Information stored for SSA names. */ |
5f240ec4 ZD |
172 | struct ssa_name_info |
173 | { | |
38635499 | 174 | /* The current reaching definition replacing this SSA name. */ |
95dd3097 ZD |
175 | tree current_def; |
176 | ||
5f240ec4 ZD |
177 | /* This field indicates whether or not the variable may need PHI nodes. |
178 | See the enum's definition for more detailed information about the | |
179 | states. */ | |
180 | ENUM_BITFIELD (need_phi_state) need_phi_state : 2; | |
181 | ||
95dd3097 | 182 | /* Age of this record (so that info_for_ssa_name table can be cleared |
fa10beec | 183 | quickly); if AGE < CURRENT_INFO_FOR_SSA_NAME_AGE, then the fields |
95dd3097 ZD |
184 | are assumed to be null. */ |
185 | unsigned age; | |
5f240ec4 | 186 | }; |
6de9cd9a | 187 | |
95dd3097 ZD |
188 | /* The information associated with names. */ |
189 | typedef struct ssa_name_info *ssa_name_info_p; | |
190 | DEF_VEC_P (ssa_name_info_p); | |
191 | DEF_VEC_ALLOC_P (ssa_name_info_p, heap); | |
192 | ||
193 | static VEC(ssa_name_info_p, heap) *info_for_ssa_name; | |
194 | static unsigned current_info_for_ssa_name_age; | |
195 | ||
196 | /* The set of blocks affected by update_ssa. */ | |
95dd3097 | 197 | static bitmap blocks_to_update; |
6de9cd9a | 198 | |
0bca51f0 DN |
199 | /* The main entry point to the SSA renamer (rewrite_blocks) may be |
200 | called several times to do different, but related, tasks. | |
201 | Initially, we need it to rename the whole program into SSA form. | |
202 | At other times, we may need it to only rename into SSA newly | |
203 | exposed symbols. Finally, we can also call it to incrementally fix | |
204 | an already built SSA web. */ | |
205 | enum rewrite_mode { | |
206 | /* Convert the whole function into SSA form. */ | |
207 | REWRITE_ALL, | |
208 | ||
209 | /* Incrementally update the SSA web by replacing existing SSA | |
210 | names with new ones. See update_ssa for details. */ | |
211 | REWRITE_UPDATE | |
212 | }; | |
213 | ||
214 | ||
0bca51f0 | 215 | |
7d5f9cc6 | 216 | |
84d65814 DN |
217 | /* Prototypes for debugging functions. */ |
218 | extern void dump_tree_ssa (FILE *); | |
219 | extern void debug_tree_ssa (void); | |
220 | extern void debug_def_blocks (void); | |
221 | extern void dump_tree_ssa_stats (FILE *); | |
222 | extern void debug_tree_ssa_stats (void); | |
38635499 DN |
223 | extern void dump_update_ssa (FILE *); |
224 | extern void debug_update_ssa (void); | |
225 | extern void dump_names_replaced_by (FILE *, tree); | |
226 | extern void debug_names_replaced_by (tree); | |
227 | extern void dump_def_blocks (FILE *); | |
228 | extern void debug_def_blocks (void); | |
229 | extern void dump_defs_stack (FILE *, int); | |
230 | extern void debug_defs_stack (int); | |
231 | extern void dump_currdefs (FILE *); | |
232 | extern void debug_currdefs (void); | |
84d65814 | 233 | |
726a989a RB |
234 | /* Return true if STMT needs to be rewritten. When renaming a subset |
235 | of the variables, not all statements will be processed. This is | |
236 | decided in mark_def_sites. */ | |
237 | ||
238 | static inline bool | |
239 | rewrite_uses_p (gimple stmt) | |
240 | { | |
241 | return gimple_visited_p (stmt); | |
242 | } | |
243 | ||
244 | ||
245 | /* Set the rewrite marker on STMT to the value given by REWRITE_P. */ | |
246 | ||
247 | static inline void | |
248 | set_rewrite_uses (gimple stmt, bool rewrite_p) | |
249 | { | |
250 | gimple_set_visited (stmt, rewrite_p); | |
251 | } | |
252 | ||
253 | ||
254 | /* Return true if the DEFs created by statement STMT should be | |
255 | registered when marking new definition sites. This is slightly | |
256 | different than rewrite_uses_p: it's used by update_ssa to | |
257 | distinguish statements that need to have both uses and defs | |
258 | processed from those that only need to have their defs processed. | |
259 | Statements that define new SSA names only need to have their defs | |
260 | registered, but they don't need to have their uses renamed. */ | |
261 | ||
262 | static inline bool | |
263 | register_defs_p (gimple stmt) | |
264 | { | |
265 | return gimple_plf (stmt, GF_PLF_1) != 0; | |
266 | } | |
267 | ||
268 | ||
269 | /* If REGISTER_DEFS_P is true, mark STMT to have its DEFs registered. */ | |
270 | ||
271 | static inline void | |
272 | set_register_defs (gimple stmt, bool register_defs_p) | |
273 | { | |
274 | gimple_set_plf (stmt, GF_PLF_1, register_defs_p); | |
275 | } | |
276 | ||
277 | ||
5f240ec4 ZD |
278 | /* Get the information associated with NAME. */ |
279 | ||
38635499 | 280 | static inline ssa_name_info_p |
5f240ec4 ZD |
281 | get_ssa_name_ann (tree name) |
282 | { | |
95dd3097 ZD |
283 | unsigned ver = SSA_NAME_VERSION (name); |
284 | unsigned len = VEC_length (ssa_name_info_p, info_for_ssa_name); | |
285 | struct ssa_name_info *info; | |
286 | ||
287 | if (ver >= len) | |
288 | { | |
289 | unsigned new_len = num_ssa_names; | |
290 | ||
291 | VEC_reserve (ssa_name_info_p, heap, info_for_ssa_name, new_len); | |
292 | while (len++ < new_len) | |
293 | { | |
294 | struct ssa_name_info *info = XCNEW (struct ssa_name_info); | |
295 | info->age = current_info_for_ssa_name_age; | |
296 | VEC_quick_push (ssa_name_info_p, info_for_ssa_name, info); | |
297 | } | |
298 | } | |
299 | ||
300 | info = VEC_index (ssa_name_info_p, info_for_ssa_name, ver); | |
301 | if (info->age < current_info_for_ssa_name_age) | |
302 | { | |
32e8bb8e | 303 | info->need_phi_state = NEED_PHI_STATE_UNKNOWN; |
95dd3097 ZD |
304 | info->current_def = NULL_TREE; |
305 | info->age = current_info_for_ssa_name_age; | |
306 | } | |
5f240ec4 | 307 | |
95dd3097 | 308 | return info; |
5f240ec4 ZD |
309 | } |
310 | ||
38635499 DN |
311 | |
312 | /* Clears info for SSA names. */ | |
95dd3097 ZD |
313 | |
314 | static void | |
315 | clear_ssa_name_info (void) | |
316 | { | |
317 | current_info_for_ssa_name_age++; | |
318 | } | |
7256233c | 319 | |
38635499 DN |
320 | |
321 | /* Get phi_state field for VAR. */ | |
5f240ec4 ZD |
322 | |
323 | static inline enum need_phi_state | |
324 | get_phi_state (tree var) | |
325 | { | |
326 | if (TREE_CODE (var) == SSA_NAME) | |
327 | return get_ssa_name_ann (var)->need_phi_state; | |
328 | else | |
329 | return var_ann (var)->need_phi_state; | |
330 | } | |
331 | ||
7256233c | 332 | |
5f240ec4 ZD |
333 | /* Sets phi_state field for VAR to STATE. */ |
334 | ||
335 | static inline void | |
336 | set_phi_state (tree var, enum need_phi_state state) | |
337 | { | |
338 | if (TREE_CODE (var) == SSA_NAME) | |
339 | get_ssa_name_ann (var)->need_phi_state = state; | |
340 | else | |
341 | var_ann (var)->need_phi_state = state; | |
342 | } | |
343 | ||
7256233c | 344 | |
5f240ec4 ZD |
345 | /* Return the current definition for VAR. */ |
346 | ||
84d65814 | 347 | tree |
5f240ec4 ZD |
348 | get_current_def (tree var) |
349 | { | |
350 | if (TREE_CODE (var) == SSA_NAME) | |
351 | return get_ssa_name_ann (var)->current_def; | |
352 | else | |
353 | return var_ann (var)->current_def; | |
354 | } | |
355 | ||
7256233c | 356 | |
5f240ec4 ZD |
357 | /* Sets current definition of VAR to DEF. */ |
358 | ||
84d65814 | 359 | void |
5f240ec4 ZD |
360 | set_current_def (tree var, tree def) |
361 | { | |
362 | if (TREE_CODE (var) == SSA_NAME) | |
363 | get_ssa_name_ann (var)->current_def = def; | |
364 | else | |
365 | var_ann (var)->current_def = def; | |
366 | } | |
367 | ||
7256233c | 368 | |
fa10beec | 369 | /* Compute global livein information given the set of blocks where |
6de9cd9a DN |
370 | an object is locally live at the start of the block (LIVEIN) |
371 | and the set of blocks where the object is defined (DEF_BLOCKS). | |
372 | ||
373 | Note: This routine augments the existing local livein information | |
374 | to include global livein (i.e., it modifies the underlying bitmap | |
375 | for LIVEIN). */ | |
376 | ||
5f240ec4 | 377 | void |
726a989a | 378 | compute_global_livein (bitmap livein ATTRIBUTE_UNUSED, bitmap def_blocks ATTRIBUTE_UNUSED) |
6de9cd9a DN |
379 | { |
380 | basic_block bb, *worklist, *tos; | |
3cd8c58a | 381 | unsigned i; |
87c476a2 | 382 | bitmap_iterator bi; |
6de9cd9a DN |
383 | |
384 | tos = worklist | |
0bca51f0 | 385 | = (basic_block *) xmalloc (sizeof (basic_block) * (last_basic_block + 1)); |
6de9cd9a | 386 | |
87c476a2 | 387 | EXECUTE_IF_SET_IN_BITMAP (livein, 0, i, bi) |
38635499 | 388 | *tos++ = BASIC_BLOCK (i); |
6de9cd9a DN |
389 | |
390 | /* Iterate until the worklist is empty. */ | |
391 | while (tos != worklist) | |
392 | { | |
393 | edge e; | |
628f6a4e | 394 | edge_iterator ei; |
6de9cd9a DN |
395 | |
396 | /* Pull a block off the worklist. */ | |
397 | bb = *--tos; | |
398 | ||
399 | /* For each predecessor block. */ | |
628f6a4e | 400 | FOR_EACH_EDGE (e, ei, bb->preds) |
6de9cd9a DN |
401 | { |
402 | basic_block pred = e->src; | |
403 | int pred_index = pred->index; | |
404 | ||
405 | /* None of this is necessary for the entry block. */ | |
406 | if (pred != ENTRY_BLOCK_PTR | |
407 | && ! bitmap_bit_p (livein, pred_index) | |
408 | && ! bitmap_bit_p (def_blocks, pred_index)) | |
409 | { | |
410 | *tos++ = pred; | |
411 | bitmap_set_bit (livein, pred_index); | |
412 | } | |
413 | } | |
414 | } | |
415 | ||
416 | free (worklist); | |
417 | } | |
418 | ||
419 | ||
95dd3097 ZD |
420 | /* Cleans up the REWRITE_THIS_STMT and REGISTER_DEFS_IN_THIS_STMT flags for |
421 | all statements in basic block BB. */ | |
422 | ||
423 | static void | |
424 | initialize_flags_in_bb (basic_block bb) | |
425 | { | |
726a989a RB |
426 | gimple stmt; |
427 | gimple_stmt_iterator gsi; | |
95dd3097 | 428 | |
726a989a | 429 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
95dd3097 | 430 | { |
726a989a RB |
431 | gimple phi = gsi_stmt (gsi); |
432 | set_rewrite_uses (phi, false); | |
433 | set_register_defs (phi, false); | |
95dd3097 ZD |
434 | } |
435 | ||
726a989a | 436 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
95dd3097 | 437 | { |
726a989a RB |
438 | stmt = gsi_stmt (gsi); |
439 | ||
95dd3097 ZD |
440 | /* We are going to use the operand cache API, such as |
441 | SET_USE, SET_DEF, and FOR_EACH_IMM_USE_FAST. The operand | |
442 | cache for each statement should be up-to-date. */ | |
726a989a RB |
443 | gcc_assert (!gimple_modified_p (stmt)); |
444 | set_rewrite_uses (stmt, false); | |
445 | set_register_defs (stmt, false); | |
95dd3097 ZD |
446 | } |
447 | } | |
448 | ||
449 | /* Mark block BB as interesting for update_ssa. */ | |
450 | ||
451 | static void | |
452 | mark_block_for_update (basic_block bb) | |
453 | { | |
454 | gcc_assert (blocks_to_update != NULL); | |
f3cf730b | 455 | if (!bitmap_set_bit (blocks_to_update, bb->index)) |
95dd3097 | 456 | return; |
95dd3097 ZD |
457 | initialize_flags_in_bb (bb); |
458 | } | |
459 | ||
7256233c DN |
460 | /* Return the set of blocks where variable VAR is defined and the blocks |
461 | where VAR is live on entry (livein). If no entry is found in | |
462 | DEF_BLOCKS, a new one is created and returned. */ | |
6de9cd9a | 463 | |
7256233c DN |
464 | static inline struct def_blocks_d * |
465 | get_def_blocks_for (tree var) | |
6de9cd9a | 466 | { |
7256233c DN |
467 | struct def_blocks_d db, *db_p; |
468 | void **slot; | |
6de9cd9a | 469 | |
7256233c DN |
470 | db.var = var; |
471 | slot = htab_find_slot (def_blocks, (void *) &db, INSERT); | |
472 | if (*slot == NULL) | |
6de9cd9a | 473 | { |
858904db | 474 | db_p = XNEW (struct def_blocks_d); |
7256233c DN |
475 | db_p->var = var; |
476 | db_p->def_blocks = BITMAP_ALLOC (NULL); | |
477 | db_p->phi_blocks = BITMAP_ALLOC (NULL); | |
478 | db_p->livein_blocks = BITMAP_ALLOC (NULL); | |
479 | *slot = (void *) db_p; | |
a32b97a2 | 480 | } |
7256233c DN |
481 | else |
482 | db_p = (struct def_blocks_d *) *slot; | |
a32b97a2 | 483 | |
7256233c | 484 | return db_p; |
6de9cd9a DN |
485 | } |
486 | ||
7d5f9cc6 | 487 | |
5f240ec4 | 488 | /* Mark block BB as the definition site for variable VAR. PHI_P is true if |
0bca51f0 | 489 | VAR is defined by a PHI node. */ |
6de9cd9a DN |
490 | |
491 | static void | |
0bca51f0 | 492 | set_def_block (tree var, basic_block bb, bool phi_p) |
6de9cd9a DN |
493 | { |
494 | struct def_blocks_d *db_p; | |
34eb8991 JL |
495 | enum need_phi_state state; |
496 | ||
5f240ec4 | 497 | state = get_phi_state (var); |
6de9cd9a DN |
498 | db_p = get_def_blocks_for (var); |
499 | ||
500 | /* Set the bit corresponding to the block where VAR is defined. */ | |
501 | bitmap_set_bit (db_p->def_blocks, bb->index); | |
5f240ec4 ZD |
502 | if (phi_p) |
503 | bitmap_set_bit (db_p->phi_blocks, bb->index); | |
6de9cd9a | 504 | |
7256233c | 505 | /* Keep track of whether or not we may need to insert PHI nodes. |
6de9cd9a DN |
506 | |
507 | If we are in the UNKNOWN state, then this is the first definition | |
508 | of VAR. Additionally, we have not seen any uses of VAR yet, so | |
7256233c | 509 | we do not need a PHI node for this variable at this time (i.e., |
6de9cd9a DN |
510 | transition to NEED_PHI_STATE_NO). |
511 | ||
512 | If we are in any other state, then we either have multiple definitions | |
513 | of this variable occurring in different blocks or we saw a use of the | |
514 | variable which was not dominated by the block containing the | |
515 | definition(s). In this case we may need a PHI node, so enter | |
516 | state NEED_PHI_STATE_MAYBE. */ | |
517 | if (state == NEED_PHI_STATE_UNKNOWN) | |
5f240ec4 | 518 | set_phi_state (var, NEED_PHI_STATE_NO); |
6de9cd9a | 519 | else |
5f240ec4 | 520 | set_phi_state (var, NEED_PHI_STATE_MAYBE); |
6de9cd9a DN |
521 | } |
522 | ||
523 | ||
524 | /* Mark block BB as having VAR live at the entry to BB. */ | |
525 | ||
526 | static void | |
527 | set_livein_block (tree var, basic_block bb) | |
528 | { | |
529 | struct def_blocks_d *db_p; | |
5f240ec4 | 530 | enum need_phi_state state = get_phi_state (var); |
6de9cd9a DN |
531 | |
532 | db_p = get_def_blocks_for (var); | |
533 | ||
534 | /* Set the bit corresponding to the block where VAR is live in. */ | |
535 | bitmap_set_bit (db_p->livein_blocks, bb->index); | |
536 | ||
7256233c | 537 | /* Keep track of whether or not we may need to insert PHI nodes. |
6de9cd9a DN |
538 | |
539 | If we reach here in NEED_PHI_STATE_NO, see if this use is dominated | |
540 | by the single block containing the definition(s) of this variable. If | |
541 | it is, then we remain in NEED_PHI_STATE_NO, otherwise we transition to | |
542 | NEED_PHI_STATE_MAYBE. */ | |
543 | if (state == NEED_PHI_STATE_NO) | |
544 | { | |
545 | int def_block_index = bitmap_first_set_bit (db_p->def_blocks); | |
546 | ||
547 | if (def_block_index == -1 | |
548 | || ! dominated_by_p (CDI_DOMINATORS, bb, | |
549 | BASIC_BLOCK (def_block_index))) | |
5f240ec4 | 550 | set_phi_state (var, NEED_PHI_STATE_MAYBE); |
6de9cd9a DN |
551 | } |
552 | else | |
5f240ec4 | 553 | set_phi_state (var, NEED_PHI_STATE_MAYBE); |
6de9cd9a DN |
554 | } |
555 | ||
556 | ||
0bca51f0 | 557 | /* Return true if symbol SYM is marked for renaming. */ |
6de9cd9a | 558 | |
70f34814 | 559 | bool |
0bca51f0 | 560 | symbol_marked_for_renaming (tree sym) |
6de9cd9a | 561 | { |
5006671f | 562 | return bitmap_bit_p (SYMS_TO_RENAME (cfun), DECL_UID (sym)); |
0bca51f0 DN |
563 | } |
564 | ||
565 | ||
566 | /* Return true if NAME is in OLD_SSA_NAMES. */ | |
6de9cd9a | 567 | |
0bca51f0 DN |
568 | static inline bool |
569 | is_old_name (tree name) | |
570 | { | |
84d65814 | 571 | unsigned ver = SSA_NAME_VERSION (name); |
5006671f RG |
572 | if (!new_ssa_names) |
573 | return false; | |
84d65814 | 574 | return ver < new_ssa_names->n_bits && TEST_BIT (old_ssa_names, ver); |
0bca51f0 DN |
575 | } |
576 | ||
577 | ||
578 | /* Return true if NAME is in NEW_SSA_NAMES. */ | |
34eb8991 | 579 | |
0bca51f0 DN |
580 | static inline bool |
581 | is_new_name (tree name) | |
582 | { | |
84d65814 | 583 | unsigned ver = SSA_NAME_VERSION (name); |
5006671f RG |
584 | if (!new_ssa_names) |
585 | return false; | |
84d65814 | 586 | return ver < new_ssa_names->n_bits && TEST_BIT (new_ssa_names, ver); |
6de9cd9a DN |
587 | } |
588 | ||
7256233c | 589 | |
0bca51f0 | 590 | /* Hashing and equality functions for REPL_TBL. */ |
d00ad49b | 591 | |
0bca51f0 DN |
592 | static hashval_t |
593 | repl_map_hash (const void *p) | |
d00ad49b | 594 | { |
0bca51f0 DN |
595 | return htab_hash_pointer ((const void *)((const struct repl_map_d *)p)->name); |
596 | } | |
d00ad49b | 597 | |
0bca51f0 DN |
598 | static int |
599 | repl_map_eq (const void *p1, const void *p2) | |
600 | { | |
601 | return ((const struct repl_map_d *)p1)->name | |
602 | == ((const struct repl_map_d *)p2)->name; | |
603 | } | |
604 | ||
605 | static void | |
606 | repl_map_free (void *p) | |
607 | { | |
608 | BITMAP_FREE (((struct repl_map_d *)p)->set); | |
609 | free (p); | |
610 | } | |
611 | ||
612 | ||
82d6e6fc | 613 | /* Return the names replaced by NEW_TREE (i.e., REPL_TBL[NEW_TREE].SET). */ |
0bca51f0 DN |
614 | |
615 | static inline bitmap | |
82d6e6fc | 616 | names_replaced_by (tree new_tree) |
0bca51f0 DN |
617 | { |
618 | struct repl_map_d m; | |
619 | void **slot; | |
620 | ||
82d6e6fc | 621 | m.name = new_tree; |
0bca51f0 DN |
622 | slot = htab_find_slot (repl_tbl, (void *) &m, NO_INSERT); |
623 | ||
624 | /* If N was not registered in the replacement table, return NULL. */ | |
625 | if (slot == NULL || *slot == NULL) | |
626 | return NULL; | |
627 | ||
628 | return ((struct repl_map_d *) *slot)->set; | |
629 | } | |
630 | ||
631 | ||
82d6e6fc | 632 | /* Add OLD to REPL_TBL[NEW_TREE].SET. */ |
0bca51f0 DN |
633 | |
634 | static inline void | |
82d6e6fc | 635 | add_to_repl_tbl (tree new_tree, tree old) |
0bca51f0 DN |
636 | { |
637 | struct repl_map_d m, *mp; | |
638 | void **slot; | |
639 | ||
82d6e6fc | 640 | m.name = new_tree; |
0bca51f0 DN |
641 | slot = htab_find_slot (repl_tbl, (void *) &m, INSERT); |
642 | if (*slot == NULL) | |
643 | { | |
858904db | 644 | mp = XNEW (struct repl_map_d); |
82d6e6fc | 645 | mp->name = new_tree; |
0bca51f0 DN |
646 | mp->set = BITMAP_ALLOC (NULL); |
647 | *slot = (void *) mp; | |
648 | } | |
649 | else | |
650 | mp = (struct repl_map_d *) *slot; | |
651 | ||
652 | bitmap_set_bit (mp->set, SSA_NAME_VERSION (old)); | |
653 | } | |
654 | ||
655 | ||
82d6e6fc | 656 | /* Add a new mapping NEW_TREE -> OLD REPL_TBL. Every entry N_i in REPL_TBL |
0bca51f0 DN |
657 | represents the set of names O_1 ... O_j replaced by N_i. This is |
658 | used by update_ssa and its helpers to introduce new SSA names in an | |
659 | already formed SSA web. */ | |
660 | ||
661 | static void | |
82d6e6fc | 662 | add_new_name_mapping (tree new_tree, tree old) |
0bca51f0 DN |
663 | { |
664 | timevar_push (TV_TREE_SSA_INCREMENTAL); | |
665 | ||
82d6e6fc KG |
666 | /* OLD and NEW_TREE must be different SSA names for the same symbol. */ |
667 | gcc_assert (new_tree != old && SSA_NAME_VAR (new_tree) == SSA_NAME_VAR (old)); | |
84d65814 | 668 | |
84d65814 | 669 | /* If this mapping is for virtual names, we will need to update |
38635499 DN |
670 | virtual operands. If this is a mapping for .MEM, then we gather |
671 | the symbols associated with each name. */ | |
82d6e6fc | 672 | if (!is_gimple_reg (new_tree)) |
0bca51f0 DN |
673 | { |
674 | tree sym; | |
675 | ||
38635499 DN |
676 | update_ssa_stats.num_virtual_mappings++; |
677 | update_ssa_stats.num_virtual_symbols++; | |
678 | ||
84d65814 DN |
679 | /* Keep counts of virtual mappings and symbols to use in the |
680 | virtual mapping heuristic. If we have large numbers of | |
681 | virtual mappings for a relatively low number of symbols, it | |
682 | will make more sense to rename the symbols from scratch. | |
683 | Otherwise, the insertion of PHI nodes for each of the old | |
684 | names in these mappings will be very slow. */ | |
82d6e6fc | 685 | sym = SSA_NAME_VAR (new_tree); |
38635499 DN |
686 | bitmap_set_bit (update_ssa_stats.virtual_symbols, DECL_UID (sym)); |
687 | } | |
688 | ||
689 | /* We may need to grow NEW_SSA_NAMES and OLD_SSA_NAMES because our | |
690 | caller may have created new names since the set was created. */ | |
691 | if (new_ssa_names->n_bits <= num_ssa_names - 1) | |
692 | { | |
693 | unsigned int new_sz = num_ssa_names + NAME_SETS_GROWTH_FACTOR; | |
694 | new_ssa_names = sbitmap_resize (new_ssa_names, new_sz, 0); | |
695 | old_ssa_names = sbitmap_resize (old_ssa_names, new_sz, 0); | |
0bca51f0 DN |
696 | } |
697 | ||
0bca51f0 | 698 | /* Update the REPL_TBL table. */ |
82d6e6fc | 699 | add_to_repl_tbl (new_tree, old); |
d00ad49b | 700 | |
0bca51f0 | 701 | /* If OLD had already been registered as a new name, then all the |
82d6e6fc | 702 | names that OLD replaces should also be replaced by NEW_TREE. */ |
0bca51f0 | 703 | if (is_new_name (old)) |
82d6e6fc | 704 | bitmap_ior_into (names_replaced_by (new_tree), names_replaced_by (old)); |
0bca51f0 | 705 | |
82d6e6fc | 706 | /* Register NEW_TREE and OLD in NEW_SSA_NAMES and OLD_SSA_NAMES, |
0bca51f0 | 707 | respectively. */ |
82d6e6fc | 708 | SET_BIT (new_ssa_names, SSA_NAME_VERSION (new_tree)); |
0bca51f0 DN |
709 | SET_BIT (old_ssa_names, SSA_NAME_VERSION (old)); |
710 | ||
84d65814 DN |
711 | /* Update mapping counter to use in the virtual mapping heuristic. */ |
712 | update_ssa_stats.num_total_mappings++; | |
0bca51f0 DN |
713 | |
714 | timevar_pop (TV_TREE_SSA_INCREMENTAL); | |
d00ad49b | 715 | } |
6de9cd9a | 716 | |
6de9cd9a | 717 | |
7256233c DN |
718 | /* Call back for walk_dominator_tree used to collect definition sites |
719 | for every variable in the function. For every statement S in block | |
720 | BB: | |
6de9cd9a | 721 | |
f47c96aa | 722 | 1- Variables defined by S in the DEFS of S are marked in the bitmap |
ccf5c864 | 723 | KILLS. |
6de9cd9a | 724 | |
7256233c | 725 | 2- If S uses a variable VAR and there is no preceding kill of VAR, |
7b71de26 | 726 | then it is marked in the LIVEIN_BLOCKS bitmap associated with VAR. |
6de9cd9a | 727 | |
7256233c DN |
728 | This information is used to determine which variables are live |
729 | across block boundaries to reduce the number of PHI nodes | |
730 | we create. */ | |
6de9cd9a | 731 | |
7256233c | 732 | static void |
ccf5c864 | 733 | mark_def_sites (basic_block bb, gimple stmt, bitmap kills) |
7256233c | 734 | { |
726a989a | 735 | tree def; |
7256233c | 736 | use_operand_p use_p; |
7256233c DN |
737 | ssa_op_iter iter; |
738 | ||
726a989a RB |
739 | /* Since this is the first time that we rewrite the program into SSA |
740 | form, force an operand scan on every statement. */ | |
726a989a | 741 | update_stmt (stmt); |
7256233c | 742 | |
95dd3097 | 743 | gcc_assert (blocks_to_update == NULL); |
726a989a RB |
744 | set_register_defs (stmt, false); |
745 | set_rewrite_uses (stmt, false); | |
7256233c | 746 | |
b5b8b0ac AO |
747 | if (is_gimple_debug (stmt)) |
748 | return; | |
749 | ||
7256233c DN |
750 | /* If a variable is used before being set, then the variable is live |
751 | across a block boundary, so mark it live-on-entry to BB. */ | |
38635499 | 752 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) |
7256233c | 753 | { |
0bca51f0 DN |
754 | tree sym = USE_FROM_PTR (use_p); |
755 | gcc_assert (DECL_P (sym)); | |
a3648cfc | 756 | if (!bitmap_bit_p (kills, DECL_UID (sym))) |
0bca51f0 | 757 | set_livein_block (sym, bb); |
726a989a | 758 | set_rewrite_uses (stmt, true); |
7256233c | 759 | } |
b8698a0f | 760 | |
38635499 DN |
761 | /* Now process the defs. Mark BB as the definition block and add |
762 | each def to the set of killed symbols. */ | |
763 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF) | |
7256233c | 764 | { |
0bca51f0 DN |
765 | gcc_assert (DECL_P (def)); |
766 | set_def_block (def, bb, false); | |
a3648cfc | 767 | bitmap_set_bit (kills, DECL_UID (def)); |
726a989a | 768 | set_register_defs (stmt, true); |
7256233c | 769 | } |
0bca51f0 DN |
770 | |
771 | /* If we found the statement interesting then also mark the block BB | |
772 | as interesting. */ | |
726a989a | 773 | if (rewrite_uses_p (stmt) || register_defs_p (stmt)) |
ccf5c864 | 774 | SET_BIT (interesting_blocks, bb->index); |
7256233c DN |
775 | } |
776 | ||
f074ff6c ZD |
777 | /* Structure used by prune_unused_phi_nodes to record bounds of the intervals |
778 | in the dfs numbering of the dominance tree. */ | |
779 | ||
780 | struct dom_dfsnum | |
781 | { | |
782 | /* Basic block whose index this entry corresponds to. */ | |
783 | unsigned bb_index; | |
784 | ||
785 | /* The dfs number of this node. */ | |
786 | unsigned dfs_num; | |
787 | }; | |
788 | ||
789 | /* Compares two entries of type struct dom_dfsnum by dfs_num field. Callback | |
790 | for qsort. */ | |
791 | ||
792 | static int | |
793 | cmp_dfsnum (const void *a, const void *b) | |
794 | { | |
3d9a9f94 KG |
795 | const struct dom_dfsnum *const da = (const struct dom_dfsnum *) a; |
796 | const struct dom_dfsnum *const db = (const struct dom_dfsnum *) b; | |
f074ff6c ZD |
797 | |
798 | return (int) da->dfs_num - (int) db->dfs_num; | |
799 | } | |
800 | ||
801 | /* Among the intervals starting at the N points specified in DEFS, find | |
802 | the one that contains S, and return its bb_index. */ | |
803 | ||
804 | static unsigned | |
805 | find_dfsnum_interval (struct dom_dfsnum *defs, unsigned n, unsigned s) | |
806 | { | |
807 | unsigned f = 0, t = n, m; | |
808 | ||
809 | while (t > f + 1) | |
810 | { | |
811 | m = (f + t) / 2; | |
812 | if (defs[m].dfs_num <= s) | |
813 | f = m; | |
814 | else | |
815 | t = m; | |
816 | } | |
817 | ||
818 | return defs[f].bb_index; | |
819 | } | |
820 | ||
821 | /* Clean bits from PHIS for phi nodes whose value cannot be used in USES. | |
822 | KILLS is a bitmap of blocks where the value is defined before any use. */ | |
823 | ||
824 | static void | |
825 | prune_unused_phi_nodes (bitmap phis, bitmap kills, bitmap uses) | |
826 | { | |
827 | VEC(int, heap) *worklist; | |
828 | bitmap_iterator bi; | |
829 | unsigned i, b, p, u, top; | |
830 | bitmap live_phis; | |
831 | basic_block def_bb, use_bb; | |
832 | edge e; | |
833 | edge_iterator ei; | |
834 | bitmap to_remove; | |
835 | struct dom_dfsnum *defs; | |
836 | unsigned n_defs, adef; | |
837 | ||
838 | if (bitmap_empty_p (uses)) | |
839 | { | |
840 | bitmap_clear (phis); | |
841 | return; | |
842 | } | |
843 | ||
844 | /* The phi must dominate a use, or an argument of a live phi. Also, we | |
845 | do not create any phi nodes in def blocks, unless they are also livein. */ | |
846 | to_remove = BITMAP_ALLOC (NULL); | |
847 | bitmap_and_compl (to_remove, kills, uses); | |
848 | bitmap_and_compl_into (phis, to_remove); | |
849 | if (bitmap_empty_p (phis)) | |
850 | { | |
851 | BITMAP_FREE (to_remove); | |
852 | return; | |
853 | } | |
854 | ||
855 | /* We want to remove the unnecessary phi nodes, but we do not want to compute | |
856 | liveness information, as that may be linear in the size of CFG, and if | |
857 | there are lot of different variables to rewrite, this may lead to quadratic | |
858 | behavior. | |
859 | ||
860 | Instead, we basically emulate standard dce. We put all uses to worklist, | |
861 | then for each of them find the nearest def that dominates them. If this | |
862 | def is a phi node, we mark it live, and if it was not live before, we | |
863 | add the predecessors of its basic block to the worklist. | |
b8698a0f | 864 | |
f074ff6c ZD |
865 | To quickly locate the nearest def that dominates use, we use dfs numbering |
866 | of the dominance tree (that is already available in order to speed up | |
867 | queries). For each def, we have the interval given by the dfs number on | |
868 | entry to and on exit from the corresponding subtree in the dominance tree. | |
869 | The nearest dominator for a given use is the smallest of these intervals | |
870 | that contains entry and exit dfs numbers for the basic block with the use. | |
871 | If we store the bounds for all the uses to an array and sort it, we can | |
872 | locate the nearest dominating def in logarithmic time by binary search.*/ | |
873 | bitmap_ior (to_remove, kills, phis); | |
874 | n_defs = bitmap_count_bits (to_remove); | |
875 | defs = XNEWVEC (struct dom_dfsnum, 2 * n_defs + 1); | |
876 | defs[0].bb_index = 1; | |
877 | defs[0].dfs_num = 0; | |
878 | adef = 1; | |
879 | EXECUTE_IF_SET_IN_BITMAP (to_remove, 0, i, bi) | |
880 | { | |
881 | def_bb = BASIC_BLOCK (i); | |
882 | defs[adef].bb_index = i; | |
883 | defs[adef].dfs_num = bb_dom_dfs_in (CDI_DOMINATORS, def_bb); | |
884 | defs[adef + 1].bb_index = i; | |
885 | defs[adef + 1].dfs_num = bb_dom_dfs_out (CDI_DOMINATORS, def_bb); | |
886 | adef += 2; | |
887 | } | |
888 | BITMAP_FREE (to_remove); | |
889 | gcc_assert (adef == 2 * n_defs + 1); | |
890 | qsort (defs, adef, sizeof (struct dom_dfsnum), cmp_dfsnum); | |
891 | gcc_assert (defs[0].bb_index == 1); | |
892 | ||
893 | /* Now each DEFS entry contains the number of the basic block to that the | |
894 | dfs number corresponds. Change them to the number of basic block that | |
895 | corresponds to the interval following the dfs number. Also, for the | |
896 | dfs_out numbers, increase the dfs number by one (so that it corresponds | |
897 | to the start of the following interval, not to the end of the current | |
898 | one). We use WORKLIST as a stack. */ | |
899 | worklist = VEC_alloc (int, heap, n_defs + 1); | |
900 | VEC_quick_push (int, worklist, 1); | |
901 | top = 1; | |
902 | n_defs = 1; | |
903 | for (i = 1; i < adef; i++) | |
904 | { | |
905 | b = defs[i].bb_index; | |
906 | if (b == top) | |
907 | { | |
908 | /* This is a closing element. Interval corresponding to the top | |
909 | of the stack after removing it follows. */ | |
910 | VEC_pop (int, worklist); | |
911 | top = VEC_index (int, worklist, VEC_length (int, worklist) - 1); | |
912 | defs[n_defs].bb_index = top; | |
913 | defs[n_defs].dfs_num = defs[i].dfs_num + 1; | |
914 | } | |
915 | else | |
916 | { | |
917 | /* Opening element. Nothing to do, just push it to the stack and move | |
918 | it to the correct position. */ | |
919 | defs[n_defs].bb_index = defs[i].bb_index; | |
920 | defs[n_defs].dfs_num = defs[i].dfs_num; | |
921 | VEC_quick_push (int, worklist, b); | |
922 | top = b; | |
923 | } | |
924 | ||
925 | /* If this interval starts at the same point as the previous one, cancel | |
926 | the previous one. */ | |
927 | if (defs[n_defs].dfs_num == defs[n_defs - 1].dfs_num) | |
928 | defs[n_defs - 1].bb_index = defs[n_defs].bb_index; | |
929 | else | |
930 | n_defs++; | |
931 | } | |
932 | VEC_pop (int, worklist); | |
933 | gcc_assert (VEC_empty (int, worklist)); | |
934 | ||
935 | /* Now process the uses. */ | |
936 | live_phis = BITMAP_ALLOC (NULL); | |
937 | EXECUTE_IF_SET_IN_BITMAP (uses, 0, i, bi) | |
938 | { | |
939 | VEC_safe_push (int, heap, worklist, i); | |
940 | } | |
941 | ||
942 | while (!VEC_empty (int, worklist)) | |
943 | { | |
944 | b = VEC_pop (int, worklist); | |
945 | if (b == ENTRY_BLOCK) | |
946 | continue; | |
947 | ||
948 | /* If there is a phi node in USE_BB, it is made live. Otherwise, | |
949 | find the def that dominates the immediate dominator of USE_BB | |
950 | (the kill in USE_BB does not dominate the use). */ | |
951 | if (bitmap_bit_p (phis, b)) | |
952 | p = b; | |
953 | else | |
954 | { | |
955 | use_bb = get_immediate_dominator (CDI_DOMINATORS, BASIC_BLOCK (b)); | |
956 | p = find_dfsnum_interval (defs, n_defs, | |
957 | bb_dom_dfs_in (CDI_DOMINATORS, use_bb)); | |
958 | if (!bitmap_bit_p (phis, p)) | |
959 | continue; | |
960 | } | |
961 | ||
962 | /* If the phi node is already live, there is nothing to do. */ | |
963 | if (bitmap_bit_p (live_phis, p)) | |
964 | continue; | |
965 | ||
966 | /* Mark the phi as live, and add the new uses to the worklist. */ | |
967 | bitmap_set_bit (live_phis, p); | |
968 | def_bb = BASIC_BLOCK (p); | |
969 | FOR_EACH_EDGE (e, ei, def_bb->preds) | |
970 | { | |
971 | u = e->src->index; | |
972 | if (bitmap_bit_p (uses, u)) | |
973 | continue; | |
974 | ||
1e5787ef ZD |
975 | /* In case there is a kill directly in the use block, do not record |
976 | the use (this is also necessary for correctness, as we assume that | |
977 | uses dominated by a def directly in their block have been filtered | |
978 | out before). */ | |
979 | if (bitmap_bit_p (kills, u)) | |
980 | continue; | |
981 | ||
f074ff6c ZD |
982 | bitmap_set_bit (uses, u); |
983 | VEC_safe_push (int, heap, worklist, u); | |
984 | } | |
985 | } | |
986 | ||
987 | VEC_free (int, heap, worklist); | |
988 | bitmap_copy (phis, live_phis); | |
989 | BITMAP_FREE (live_phis); | |
990 | free (defs); | |
991 | } | |
7256233c | 992 | |
7256233c DN |
993 | /* Return the set of blocks where variable VAR is defined and the blocks |
994 | where VAR is live on entry (livein). Return NULL, if no entry is | |
995 | found in DEF_BLOCKS. */ | |
996 | ||
997 | static inline struct def_blocks_d * | |
998 | find_def_blocks_for (tree var) | |
999 | { | |
1000 | struct def_blocks_d dm; | |
1001 | dm.var = var; | |
1002 | return (struct def_blocks_d *) htab_find (def_blocks, &dm); | |
1003 | } | |
1004 | ||
1005 | ||
0bca51f0 DN |
1006 | /* Retrieve or create a default definition for symbol SYM. */ |
1007 | ||
1008 | static inline tree | |
1009 | get_default_def_for (tree sym) | |
1010 | { | |
5cd4ec7f | 1011 | tree ddef = gimple_default_def (cfun, sym); |
0bca51f0 DN |
1012 | |
1013 | if (ddef == NULL_TREE) | |
1014 | { | |
726a989a | 1015 | ddef = make_ssa_name (sym, gimple_build_nop ()); |
0bca51f0 DN |
1016 | set_default_def (sym, ddef); |
1017 | } | |
1018 | ||
1019 | return ddef; | |
1020 | } | |
1021 | ||
1022 | ||
2ce79879 ZD |
1023 | /* Marks phi node PHI in basic block BB for rewrite. */ |
1024 | ||
1025 | static void | |
726a989a | 1026 | mark_phi_for_rewrite (basic_block bb, gimple phi) |
2ce79879 | 1027 | { |
726a989a | 1028 | gimple_vec phis; |
2ce79879 ZD |
1029 | unsigned i, idx = bb->index; |
1030 | ||
726a989a | 1031 | if (rewrite_uses_p (phi)) |
2ce79879 | 1032 | return; |
38635499 | 1033 | |
726a989a | 1034 | set_rewrite_uses (phi, true); |
2ce79879 ZD |
1035 | |
1036 | if (!blocks_with_phis_to_rewrite) | |
1037 | return; | |
1038 | ||
1039 | bitmap_set_bit (blocks_with_phis_to_rewrite, idx); | |
726a989a RB |
1040 | VEC_reserve (gimple_vec, heap, phis_to_rewrite, last_basic_block + 1); |
1041 | for (i = VEC_length (gimple_vec, phis_to_rewrite); i <= idx; i++) | |
1042 | VEC_quick_push (gimple_vec, phis_to_rewrite, NULL); | |
2ce79879 | 1043 | |
726a989a | 1044 | phis = VEC_index (gimple_vec, phis_to_rewrite, idx); |
2ce79879 | 1045 | if (!phis) |
726a989a | 1046 | phis = VEC_alloc (gimple, heap, 10); |
2ce79879 | 1047 | |
726a989a RB |
1048 | VEC_safe_push (gimple, heap, phis, phi); |
1049 | VEC_replace (gimple_vec, phis_to_rewrite, idx, phis); | |
2ce79879 ZD |
1050 | } |
1051 | ||
7256233c | 1052 | /* Insert PHI nodes for variable VAR using the iterated dominance |
0bca51f0 | 1053 | frontier given in PHI_INSERTION_POINTS. If UPDATE_P is true, this |
38635499 DN |
1054 | function assumes that the caller is incrementally updating the |
1055 | existing SSA form, in which case VAR may be an SSA name instead of | |
1056 | a symbol. | |
0bca51f0 DN |
1057 | |
1058 | PHI_INSERTION_POINTS is updated to reflect nodes that already had a | |
1059 | PHI node for VAR. On exit, only the nodes that received a PHI node | |
1060 | for VAR will be present in PHI_INSERTION_POINTS. */ | |
7256233c DN |
1061 | |
1062 | static void | |
0bca51f0 | 1063 | insert_phi_nodes_for (tree var, bitmap phi_insertion_points, bool update_p) |
7256233c DN |
1064 | { |
1065 | unsigned bb_index; | |
1066 | edge e; | |
726a989a | 1067 | gimple phi; |
7256233c DN |
1068 | basic_block bb; |
1069 | bitmap_iterator bi; | |
1070 | struct def_blocks_d *def_map; | |
1071 | ||
1072 | def_map = find_def_blocks_for (var); | |
0bca51f0 | 1073 | gcc_assert (def_map); |
7256233c DN |
1074 | |
1075 | /* Remove the blocks where we already have PHI nodes for VAR. */ | |
1076 | bitmap_and_compl_into (phi_insertion_points, def_map->phi_blocks); | |
1077 | ||
f074ff6c ZD |
1078 | /* Remove obviously useless phi nodes. */ |
1079 | prune_unused_phi_nodes (phi_insertion_points, def_map->def_blocks, | |
1080 | def_map->livein_blocks); | |
7256233c DN |
1081 | |
1082 | /* And insert the PHI nodes. */ | |
f074ff6c | 1083 | EXECUTE_IF_SET_IN_BITMAP (phi_insertion_points, 0, bb_index, bi) |
7256233c DN |
1084 | { |
1085 | bb = BASIC_BLOCK (bb_index); | |
95dd3097 ZD |
1086 | if (update_p) |
1087 | mark_block_for_update (bb); | |
7256233c | 1088 | |
726a989a | 1089 | phi = NULL; |
38635499 DN |
1090 | |
1091 | if (TREE_CODE (var) == SSA_NAME) | |
7256233c | 1092 | { |
84d65814 DN |
1093 | /* If we are rewriting SSA names, create the LHS of the PHI |
1094 | node by duplicating VAR. This is useful in the case of | |
1095 | pointers, to also duplicate pointer attributes (alias | |
1096 | information, in particular). */ | |
7256233c | 1097 | edge_iterator ei; |
84d65814 | 1098 | tree new_lhs; |
0bca51f0 | 1099 | |
38635499 | 1100 | gcc_assert (update_p); |
84d65814 | 1101 | phi = create_phi_node (var, bb); |
38635499 | 1102 | |
84d65814 | 1103 | new_lhs = duplicate_ssa_name (var, phi); |
726a989a | 1104 | gimple_phi_set_result (phi, new_lhs); |
84d65814 | 1105 | add_new_name_mapping (new_lhs, var); |
0bca51f0 DN |
1106 | |
1107 | /* Add VAR to every argument slot of PHI. We need VAR in | |
1108 | every argument so that rewrite_update_phi_arguments knows | |
1109 | which name is this PHI node replacing. If VAR is a | |
1110 | symbol marked for renaming, this is not necessary, the | |
1111 | renamer will use the symbol on the LHS to get its | |
1112 | reaching definition. */ | |
7256233c | 1113 | FOR_EACH_EDGE (e, ei, bb->preds) |
f5045c96 | 1114 | add_phi_arg (phi, var, e, UNKNOWN_LOCATION); |
7256233c | 1115 | } |
84d65814 DN |
1116 | else |
1117 | { | |
b5b8b0ac | 1118 | tree tracked_var; |
3a56edc7 | 1119 | |
e24c4814 SB |
1120 | gcc_assert (DECL_P (var)); |
1121 | phi = create_phi_node (var, bb); | |
3a56edc7 AO |
1122 | |
1123 | tracked_var = target_for_debug_bind (var); | |
1124 | if (tracked_var) | |
b5b8b0ac AO |
1125 | { |
1126 | gimple note = gimple_build_debug_bind (tracked_var, | |
1127 | PHI_RESULT (phi), | |
1128 | phi); | |
1129 | gimple_stmt_iterator si = gsi_after_labels (bb); | |
1130 | gsi_insert_before (&si, note, GSI_SAME_STMT); | |
1131 | } | |
84d65814 | 1132 | } |
0bca51f0 DN |
1133 | |
1134 | /* Mark this PHI node as interesting for update_ssa. */ | |
726a989a | 1135 | set_register_defs (phi, true); |
2ce79879 | 1136 | mark_phi_for_rewrite (bb, phi); |
7256233c DN |
1137 | } |
1138 | } | |
1139 | ||
1140 | ||
7256233c DN |
1141 | /* Insert PHI nodes at the dominance frontier of blocks with variable |
1142 | definitions. DFS contains the dominance frontier information for | |
38635499 | 1143 | the flowgraph. */ |
7256233c DN |
1144 | |
1145 | static void | |
0fc555fb | 1146 | insert_phi_nodes (bitmap_head *dfs) |
7256233c | 1147 | { |
a3648cfc | 1148 | referenced_var_iterator rvi; |
e68c7b43 | 1149 | bitmap_iterator bi; |
a3648cfc | 1150 | tree var; |
e68c7b43 RG |
1151 | bitmap vars; |
1152 | unsigned uid; | |
7256233c DN |
1153 | |
1154 | timevar_push (TV_TREE_INSERT_PHI_NODES); | |
b8698a0f | 1155 | |
e68c7b43 RG |
1156 | /* Do two stages to avoid code generation differences for UID |
1157 | differences but no UID ordering differences. */ | |
1158 | ||
1159 | vars = BITMAP_ALLOC (NULL); | |
a3648cfc | 1160 | FOR_EACH_REFERENCED_VAR (var, rvi) |
5f240ec4 | 1161 | { |
84d65814 | 1162 | struct def_blocks_d *def_map; |
0bca51f0 | 1163 | |
84d65814 DN |
1164 | def_map = find_def_blocks_for (var); |
1165 | if (def_map == NULL) | |
1166 | continue; | |
1167 | ||
1168 | if (get_phi_state (var) != NEED_PHI_STATE_NO) | |
e68c7b43 | 1169 | bitmap_set_bit (vars, DECL_UID (var)); |
7256233c | 1170 | } |
5f240ec4 | 1171 | |
e68c7b43 RG |
1172 | EXECUTE_IF_SET_IN_BITMAP (vars, 0, uid, bi) |
1173 | { | |
1174 | tree var = referenced_var (uid); | |
1175 | struct def_blocks_d *def_map; | |
1176 | bitmap idf; | |
1177 | ||
1178 | def_map = find_def_blocks_for (var); | |
1179 | idf = compute_idf (def_map->def_blocks, dfs); | |
1180 | insert_phi_nodes_for (var, idf, false); | |
1181 | BITMAP_FREE (idf); | |
1182 | } | |
1183 | ||
1184 | BITMAP_FREE (vars); | |
1185 | ||
6de9cd9a DN |
1186 | timevar_pop (TV_TREE_INSERT_PHI_NODES); |
1187 | } | |
1188 | ||
1189 | ||
38635499 DN |
1190 | /* Push SYM's current reaching definition into BLOCK_DEFS_STACK and |
1191 | register DEF (an SSA_NAME) to be a new definition for SYM. */ | |
7256233c | 1192 | |
cfaab3a9 | 1193 | static void |
38635499 | 1194 | register_new_def (tree def, tree sym) |
7256233c | 1195 | { |
7256233c | 1196 | tree currdef; |
b8698a0f | 1197 | |
7256233c DN |
1198 | /* If this variable is set in a single basic block and all uses are |
1199 | dominated by the set(s) in that single basic block, then there is | |
1200 | no reason to record anything for this variable in the block local | |
1201 | definition stacks. Doing so just wastes time and memory. | |
1202 | ||
1203 | This is the same test to prune the set of variables which may | |
1204 | need PHI nodes. So we just use that information since it's already | |
1205 | computed and available for us to use. */ | |
38635499 | 1206 | if (get_phi_state (sym) == NEED_PHI_STATE_NO) |
7256233c | 1207 | { |
38635499 | 1208 | set_current_def (sym, def); |
7256233c DN |
1209 | return; |
1210 | } | |
1211 | ||
38635499 | 1212 | currdef = get_current_def (sym); |
7256233c | 1213 | |
38635499 DN |
1214 | /* If SYM is not a GIMPLE register, then CURRDEF may be a name whose |
1215 | SSA_NAME_VAR is not necessarily SYM. In this case, also push SYM | |
1216 | in the stack so that we know which symbol is being defined by | |
1217 | this SSA name when we unwind the stack. */ | |
1218 | if (currdef && !is_gimple_reg (sym)) | |
1219 | VEC_safe_push (tree, heap, block_defs_stack, sym); | |
7256233c | 1220 | |
38635499 DN |
1221 | /* Push the current reaching definition into BLOCK_DEFS_STACK. This |
1222 | stack is later used by the dominator tree callbacks to restore | |
1223 | the reaching definitions for all the variables defined in the | |
1224 | block after a recursive visit to all its immediately dominated | |
1225 | blocks. If there is no current reaching definition, then just | |
1226 | record the underlying _DECL node. */ | |
1227 | VEC_safe_push (tree, heap, block_defs_stack, currdef ? currdef : sym); | |
1228 | ||
1229 | /* Set the current reaching definition for SYM to be DEF. */ | |
1230 | set_current_def (sym, def); | |
7256233c DN |
1231 | } |
1232 | ||
1233 | ||
6de9cd9a DN |
1234 | /* Perform a depth-first traversal of the dominator tree looking for |
1235 | variables to rename. BB is the block where to start searching. | |
1236 | Renaming is a five step process: | |
1237 | ||
1238 | 1- Every definition made by PHI nodes at the start of the blocks is | |
1239 | registered as the current definition for the corresponding variable. | |
1240 | ||
1241 | 2- Every statement in BB is rewritten. USE and VUSE operands are | |
1242 | rewritten with their corresponding reaching definition. DEF and | |
1243 | VDEF targets are registered as new definitions. | |
b8698a0f | 1244 | |
6de9cd9a DN |
1245 | 3- All the PHI nodes in successor blocks of BB are visited. The |
1246 | argument corresponding to BB is replaced with its current reaching | |
1247 | definition. | |
1248 | ||
1249 | 4- Recursively rewrite every dominator child block of BB. | |
1250 | ||
1251 | 5- Restore (in reverse order) the current reaching definition for every | |
1252 | new definition introduced in this block. This is done so that when | |
1253 | we return from the recursive call, all the current reaching | |
1254 | definitions are restored to the names that were valid in the | |
1255 | dominator parent of BB. */ | |
1256 | ||
7256233c | 1257 | /* Return the current definition for variable VAR. If none is found, |
38635499 | 1258 | create a new SSA name to act as the zeroth definition for VAR. */ |
5f240ec4 | 1259 | |
7256233c DN |
1260 | static tree |
1261 | get_reaching_def (tree var) | |
1262 | { | |
38635499 | 1263 | tree currdef; |
b8698a0f | 1264 | |
7256233c | 1265 | /* Lookup the current reaching definition for VAR. */ |
38635499 | 1266 | currdef = get_current_def (var); |
5f240ec4 | 1267 | |
7256233c DN |
1268 | /* If there is no reaching definition for VAR, create and register a |
1269 | default definition for it (if needed). */ | |
38635499 | 1270 | if (currdef == NULL_TREE) |
7256233c | 1271 | { |
38635499 DN |
1272 | tree sym = DECL_P (var) ? var : SSA_NAME_VAR (var); |
1273 | currdef = get_default_def_for (sym); | |
1274 | set_current_def (var, currdef); | |
7256233c DN |
1275 | } |
1276 | ||
1277 | /* Return the current reaching definition for VAR, or the default | |
1278 | definition, if we had to create one. */ | |
38635499 | 1279 | return currdef; |
7256233c DN |
1280 | } |
1281 | ||
1282 | ||
1283 | /* SSA Rewriting Step 2. Rewrite every variable used in each statement in | |
1284 | the block with its immediate reaching definitions. Update the current | |
1285 | definition of a variable when a new real or virtual definition is found. */ | |
5f240ec4 ZD |
1286 | |
1287 | static void | |
b5b8b0ac | 1288 | rewrite_stmt (gimple_stmt_iterator si) |
5f240ec4 | 1289 | { |
7256233c DN |
1290 | use_operand_p use_p; |
1291 | def_operand_p def_p; | |
1292 | ssa_op_iter iter; | |
b5b8b0ac | 1293 | gimple stmt = gsi_stmt (si); |
7256233c | 1294 | |
7256233c DN |
1295 | /* If mark_def_sites decided that we don't need to rewrite this |
1296 | statement, ignore it. */ | |
95dd3097 | 1297 | gcc_assert (blocks_to_update == NULL); |
726a989a | 1298 | if (!rewrite_uses_p (stmt) && !register_defs_p (stmt)) |
7256233c | 1299 | return; |
5f240ec4 ZD |
1300 | |
1301 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
7256233c DN |
1302 | { |
1303 | fprintf (dump_file, "Renaming statement "); | |
726a989a | 1304 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); |
7256233c DN |
1305 | fprintf (dump_file, "\n"); |
1306 | } | |
5f240ec4 | 1307 | |
38635499 | 1308 | /* Step 1. Rewrite USES in the statement. */ |
726a989a | 1309 | if (rewrite_uses_p (stmt)) |
38635499 | 1310 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) |
0bca51f0 DN |
1311 | { |
1312 | tree var = USE_FROM_PTR (use_p); | |
1313 | gcc_assert (DECL_P (var)); | |
1314 | SET_USE (use_p, get_reaching_def (var)); | |
1315 | } | |
5f240ec4 | 1316 | |
38635499 | 1317 | /* Step 2. Register the statement's DEF operands. */ |
726a989a | 1318 | if (register_defs_p (stmt)) |
38635499 | 1319 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_DEF) |
0bca51f0 DN |
1320 | { |
1321 | tree var = DEF_FROM_PTR (def_p); | |
b5b8b0ac AO |
1322 | tree name = make_ssa_name (var, stmt); |
1323 | tree tracked_var; | |
0bca51f0 | 1324 | gcc_assert (DECL_P (var)); |
b5b8b0ac | 1325 | SET_DEF (def_p, name); |
38635499 | 1326 | register_new_def (DEF_FROM_PTR (def_p), var); |
b5b8b0ac AO |
1327 | |
1328 | tracked_var = target_for_debug_bind (var); | |
1329 | if (tracked_var) | |
1330 | { | |
1331 | gimple note = gimple_build_debug_bind (tracked_var, name, stmt); | |
1332 | gsi_insert_after (&si, note, GSI_SAME_STMT); | |
1333 | } | |
0bca51f0 | 1334 | } |
5f240ec4 | 1335 | } |
6de9cd9a | 1336 | |
7256233c | 1337 | |
6de9cd9a DN |
1338 | /* SSA Rewriting Step 3. Visit all the successor blocks of BB looking for |
1339 | PHI nodes. For every PHI node found, add a new argument containing the | |
1340 | current reaching definition for the variable and the edge through which | |
471854f8 | 1341 | that definition is reaching the PHI node. */ |
6de9cd9a DN |
1342 | |
1343 | static void | |
ccf5c864 | 1344 | rewrite_add_phi_arguments (basic_block bb) |
6de9cd9a DN |
1345 | { |
1346 | edge e; | |
628f6a4e | 1347 | edge_iterator ei; |
6de9cd9a | 1348 | |
628f6a4e | 1349 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a | 1350 | { |
726a989a RB |
1351 | gimple phi; |
1352 | gimple_stmt_iterator gsi; | |
6de9cd9a | 1353 | |
726a989a RB |
1354 | for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); |
1355 | gsi_next (&gsi)) | |
6de9cd9a DN |
1356 | { |
1357 | tree currdef; | |
f5045c96 AM |
1358 | gimple stmt; |
1359 | ||
726a989a RB |
1360 | phi = gsi_stmt (gsi); |
1361 | currdef = get_reaching_def (SSA_NAME_VAR (gimple_phi_result (phi))); | |
f5045c96 AM |
1362 | stmt = SSA_NAME_DEF_STMT (currdef); |
1363 | add_phi_arg (phi, currdef, e, gimple_location (stmt)); | |
6de9cd9a DN |
1364 | } |
1365 | } | |
1366 | } | |
1367 | ||
ccf5c864 PB |
1368 | /* SSA Rewriting Step 1. Initialization, create a block local stack |
1369 | of reaching definitions for new SSA names produced in this block | |
1370 | (BLOCK_DEFS). Register new definitions for every PHI node in the | |
1371 | block. */ | |
1372 | ||
1373 | static void | |
1374 | rewrite_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
1375 | basic_block bb) | |
1376 | { | |
1377 | gimple phi; | |
1378 | gimple_stmt_iterator gsi; | |
1379 | ||
1380 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1381 | fprintf (dump_file, "\n\nRenaming block #%d\n\n", bb->index); | |
1382 | ||
1383 | /* Mark the unwind point for this block. */ | |
1384 | VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE); | |
1385 | ||
1386 | /* Step 1. Register new definitions for every PHI node in the block. | |
1387 | Conceptually, all the PHI nodes are executed in parallel and each PHI | |
1388 | node introduces a new version for the associated variable. */ | |
1389 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1390 | { | |
1391 | tree result; | |
1392 | ||
1393 | phi = gsi_stmt (gsi); | |
1394 | result = gimple_phi_result (phi); | |
1395 | gcc_assert (is_gimple_reg (result)); | |
1396 | register_new_def (result, SSA_NAME_VAR (result)); | |
1397 | } | |
1398 | ||
1399 | /* Step 2. Rewrite every variable used in each statement in the block | |
1400 | with its immediate reaching definitions. Update the current definition | |
1401 | of a variable when a new real or virtual definition is found. */ | |
1402 | if (TEST_BIT (interesting_blocks, bb->index)) | |
1403 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
b5b8b0ac | 1404 | rewrite_stmt (gsi); |
ccf5c864 PB |
1405 | |
1406 | /* Step 3. Visit all the successor blocks of BB looking for PHI nodes. | |
1407 | For every PHI node found, add a new argument containing the current | |
1408 | reaching definition for the variable and the edge through which that | |
1409 | definition is reaching the PHI node. */ | |
1410 | rewrite_add_phi_arguments (bb); | |
1411 | } | |
1412 | ||
1413 | ||
7256233c | 1414 | |
38635499 DN |
1415 | /* Called after visiting all the statements in basic block BB and all |
1416 | of its dominator children. Restore CURRDEFS to its original value. */ | |
6de9cd9a DN |
1417 | |
1418 | static void | |
ccf5c864 PB |
1419 | rewrite_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, |
1420 | basic_block bb ATTRIBUTE_UNUSED) | |
6de9cd9a | 1421 | { |
9fae925b | 1422 | /* Restore CURRDEFS to its original state. */ |
d4e6fecb | 1423 | while (VEC_length (tree, block_defs_stack) > 0) |
6de9cd9a | 1424 | { |
d4e6fecb | 1425 | tree tmp = VEC_pop (tree, block_defs_stack); |
6de9cd9a DN |
1426 | tree saved_def, var; |
1427 | ||
9fae925b JL |
1428 | if (tmp == NULL_TREE) |
1429 | break; | |
1430 | ||
6de9cd9a DN |
1431 | if (TREE_CODE (tmp) == SSA_NAME) |
1432 | { | |
38635499 DN |
1433 | /* If we recorded an SSA_NAME, then make the SSA_NAME the |
1434 | current definition of its underlying variable. Note that | |
1435 | if the SSA_NAME is not for a GIMPLE register, the symbol | |
1436 | being defined is stored in the next slot in the stack. | |
1437 | This mechanism is needed because an SSA name for a | |
1438 | non-register symbol may be the definition for more than | |
1439 | one symbol (e.g., SFTs, aliased variables, etc). */ | |
6de9cd9a DN |
1440 | saved_def = tmp; |
1441 | var = SSA_NAME_VAR (saved_def); | |
38635499 DN |
1442 | if (!is_gimple_reg (var)) |
1443 | var = VEC_pop (tree, block_defs_stack); | |
6de9cd9a DN |
1444 | } |
1445 | else | |
1446 | { | |
38635499 DN |
1447 | /* If we recorded anything else, it must have been a _DECL |
1448 | node and its current reaching definition must have been | |
1449 | NULL. */ | |
6de9cd9a DN |
1450 | saved_def = NULL; |
1451 | var = tmp; | |
1452 | } | |
b8698a0f | 1453 | |
5f240ec4 | 1454 | set_current_def (var, saved_def); |
6de9cd9a DN |
1455 | } |
1456 | } | |
1457 | ||
1458 | ||
38635499 DN |
1459 | /* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */ |
1460 | ||
1461 | void | |
1462 | dump_decl_set (FILE *file, bitmap set) | |
1463 | { | |
1464 | if (set) | |
1465 | { | |
3b302421 RG |
1466 | bitmap_iterator bi; |
1467 | unsigned i; | |
38635499 DN |
1468 | |
1469 | fprintf (file, "{ "); | |
1470 | ||
3b302421 | 1471 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) |
38635499 | 1472 | { |
25a6a873 RG |
1473 | struct tree_decl_minimal in; |
1474 | tree var; | |
1475 | in.uid = i; | |
1476 | var = (tree) htab_find_with_hash (gimple_referenced_vars (cfun), | |
1477 | &in, i); | |
1478 | if (var) | |
1479 | print_generic_expr (file, var, 0); | |
1480 | else | |
1481 | fprintf (file, "D.%u", i); | |
38635499 DN |
1482 | fprintf (file, " "); |
1483 | } | |
1484 | ||
5006671f | 1485 | fprintf (file, "}"); |
38635499 DN |
1486 | } |
1487 | else | |
5006671f | 1488 | fprintf (file, "NIL"); |
38635499 DN |
1489 | } |
1490 | ||
1491 | ||
1492 | /* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */ | |
1493 | ||
24e47c76 | 1494 | DEBUG_FUNCTION void |
38635499 DN |
1495 | debug_decl_set (bitmap set) |
1496 | { | |
1497 | dump_decl_set (stderr, set); | |
5006671f | 1498 | fprintf (stderr, "\n"); |
38635499 DN |
1499 | } |
1500 | ||
1501 | ||
1502 | /* Dump the renaming stack (block_defs_stack) to FILE. Traverse the | |
1503 | stack up to a maximum of N levels. If N is -1, the whole stack is | |
1504 | dumped. New levels are created when the dominator tree traversal | |
1505 | used for renaming enters a new sub-tree. */ | |
1506 | ||
1507 | void | |
1508 | dump_defs_stack (FILE *file, int n) | |
1509 | { | |
1510 | int i, j; | |
1511 | ||
1512 | fprintf (file, "\n\nRenaming stack"); | |
1513 | if (n > 0) | |
1514 | fprintf (file, " (up to %d levels)", n); | |
1515 | fprintf (file, "\n\n"); | |
1516 | ||
1517 | i = 1; | |
1518 | fprintf (file, "Level %d (current level)\n", i); | |
1519 | for (j = (int) VEC_length (tree, block_defs_stack) - 1; j >= 0; j--) | |
1520 | { | |
1521 | tree name, var; | |
b8698a0f | 1522 | |
38635499 DN |
1523 | name = VEC_index (tree, block_defs_stack, j); |
1524 | if (name == NULL_TREE) | |
1525 | { | |
1526 | i++; | |
1527 | if (n > 0 && i > n) | |
1528 | break; | |
1529 | fprintf (file, "\nLevel %d\n", i); | |
1530 | continue; | |
1531 | } | |
1532 | ||
1533 | if (DECL_P (name)) | |
1534 | { | |
1535 | var = name; | |
1536 | name = NULL_TREE; | |
1537 | } | |
1538 | else | |
1539 | { | |
1540 | var = SSA_NAME_VAR (name); | |
1541 | if (!is_gimple_reg (var)) | |
1542 | { | |
1543 | j--; | |
1544 | var = VEC_index (tree, block_defs_stack, j); | |
1545 | } | |
1546 | } | |
1547 | ||
1548 | fprintf (file, " Previous CURRDEF ("); | |
1549 | print_generic_expr (file, var, 0); | |
1550 | fprintf (file, ") = "); | |
1551 | if (name) | |
1552 | print_generic_expr (file, name, 0); | |
1553 | else | |
1554 | fprintf (file, "<NIL>"); | |
1555 | fprintf (file, "\n"); | |
1556 | } | |
1557 | } | |
1558 | ||
1559 | ||
1560 | /* Dump the renaming stack (block_defs_stack) to stderr. Traverse the | |
1561 | stack up to a maximum of N levels. If N is -1, the whole stack is | |
1562 | dumped. New levels are created when the dominator tree traversal | |
1563 | used for renaming enters a new sub-tree. */ | |
1564 | ||
24e47c76 | 1565 | DEBUG_FUNCTION void |
38635499 DN |
1566 | debug_defs_stack (int n) |
1567 | { | |
1568 | dump_defs_stack (stderr, n); | |
1569 | } | |
1570 | ||
1571 | ||
1572 | /* Dump the current reaching definition of every symbol to FILE. */ | |
1573 | ||
1574 | void | |
1575 | dump_currdefs (FILE *file) | |
1576 | { | |
1577 | referenced_var_iterator i; | |
1578 | tree var; | |
1579 | ||
1580 | fprintf (file, "\n\nCurrent reaching definitions\n\n"); | |
1581 | FOR_EACH_REFERENCED_VAR (var, i) | |
5006671f RG |
1582 | if (SYMS_TO_RENAME (cfun) == NULL |
1583 | || bitmap_bit_p (SYMS_TO_RENAME (cfun), DECL_UID (var))) | |
38635499 DN |
1584 | { |
1585 | fprintf (file, "CURRDEF ("); | |
1586 | print_generic_expr (file, var, 0); | |
1587 | fprintf (file, ") = "); | |
1588 | if (get_current_def (var)) | |
1589 | print_generic_expr (file, get_current_def (var), 0); | |
1590 | else | |
1591 | fprintf (file, "<NIL>"); | |
1592 | fprintf (file, "\n"); | |
1593 | } | |
1594 | } | |
1595 | ||
1596 | ||
1597 | /* Dump the current reaching definition of every symbol to stderr. */ | |
1598 | ||
24e47c76 | 1599 | DEBUG_FUNCTION void |
38635499 DN |
1600 | debug_currdefs (void) |
1601 | { | |
1602 | dump_currdefs (stderr); | |
1603 | } | |
1604 | ||
1605 | ||
6de9cd9a DN |
1606 | /* Dump SSA information to FILE. */ |
1607 | ||
1608 | void | |
1609 | dump_tree_ssa (FILE *file) | |
1610 | { | |
6de9cd9a | 1611 | const char *funcname |
673fda6b | 1612 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
6de9cd9a | 1613 | |
38635499 | 1614 | fprintf (file, "SSA renaming information for %s\n\n", funcname); |
6de9cd9a | 1615 | |
38635499 DN |
1616 | dump_def_blocks (file); |
1617 | dump_defs_stack (file, -1); | |
1618 | dump_currdefs (file); | |
1619 | dump_tree_ssa_stats (file); | |
6de9cd9a DN |
1620 | } |
1621 | ||
1622 | ||
1623 | /* Dump SSA information to stderr. */ | |
1624 | ||
24e47c76 | 1625 | DEBUG_FUNCTION void |
6de9cd9a DN |
1626 | debug_tree_ssa (void) |
1627 | { | |
1628 | dump_tree_ssa (stderr); | |
1629 | } | |
1630 | ||
1631 | ||
7256233c DN |
1632 | /* Dump statistics for the hash table HTAB. */ |
1633 | ||
1634 | static void | |
1635 | htab_statistics (FILE *file, htab_t htab) | |
1636 | { | |
1637 | fprintf (file, "size %ld, %ld elements, %f collision/search ratio\n", | |
1638 | (long) htab_size (htab), | |
1639 | (long) htab_elements (htab), | |
1640 | htab_collisions (htab)); | |
1641 | } | |
1642 | ||
1643 | ||
6de9cd9a DN |
1644 | /* Dump SSA statistics on FILE. */ |
1645 | ||
1646 | void | |
1647 | dump_tree_ssa_stats (FILE *file) | |
1648 | { | |
38635499 DN |
1649 | if (def_blocks || repl_tbl) |
1650 | fprintf (file, "\nHash table statistics:\n"); | |
6de9cd9a | 1651 | |
38635499 DN |
1652 | if (def_blocks) |
1653 | { | |
1654 | fprintf (file, " def_blocks: "); | |
1655 | htab_statistics (file, def_blocks); | |
1656 | } | |
6de9cd9a | 1657 | |
38635499 DN |
1658 | if (repl_tbl) |
1659 | { | |
1660 | fprintf (file, " repl_tbl: "); | |
1661 | htab_statistics (file, repl_tbl); | |
1662 | } | |
1663 | ||
1664 | if (def_blocks || repl_tbl) | |
1665 | fprintf (file, "\n"); | |
6de9cd9a DN |
1666 | } |
1667 | ||
1668 | ||
1669 | /* Dump SSA statistics on stderr. */ | |
1670 | ||
24e47c76 | 1671 | DEBUG_FUNCTION void |
6de9cd9a DN |
1672 | debug_tree_ssa_stats (void) |
1673 | { | |
1674 | dump_tree_ssa_stats (stderr); | |
1675 | } | |
1676 | ||
1677 | ||
7256233c | 1678 | /* Hashing and equality functions for DEF_BLOCKS. */ |
6de9cd9a | 1679 | |
7256233c DN |
1680 | static hashval_t |
1681 | def_blocks_hash (const void *p) | |
6de9cd9a | 1682 | { |
7256233c DN |
1683 | return htab_hash_pointer |
1684 | ((const void *)((const struct def_blocks_d *)p)->var); | |
1685 | } | |
1686 | ||
1687 | static int | |
1688 | def_blocks_eq (const void *p1, const void *p2) | |
1689 | { | |
1690 | return ((const struct def_blocks_d *)p1)->var | |
1691 | == ((const struct def_blocks_d *)p2)->var; | |
6de9cd9a DN |
1692 | } |
1693 | ||
1694 | ||
7256233c | 1695 | /* Free memory allocated by one entry in DEF_BLOCKS. */ |
6de9cd9a DN |
1696 | |
1697 | static void | |
7256233c | 1698 | def_blocks_free (void *p) |
6de9cd9a | 1699 | { |
858904db | 1700 | struct def_blocks_d *entry = (struct def_blocks_d *) p; |
7256233c DN |
1701 | BITMAP_FREE (entry->def_blocks); |
1702 | BITMAP_FREE (entry->phi_blocks); | |
1703 | BITMAP_FREE (entry->livein_blocks); | |
1704 | free (entry); | |
1705 | } | |
6de9cd9a | 1706 | |
6de9cd9a | 1707 | |
7256233c | 1708 | /* Callback for htab_traverse to dump the DEF_BLOCKS hash table. */ |
6de9cd9a | 1709 | |
7256233c | 1710 | static int |
38635499 | 1711 | debug_def_blocks_r (void **slot, void *data) |
7256233c | 1712 | { |
38635499 | 1713 | FILE *file = (FILE *) data; |
7256233c | 1714 | struct def_blocks_d *db_p = (struct def_blocks_d *) *slot; |
b8698a0f | 1715 | |
38635499 DN |
1716 | fprintf (file, "VAR: "); |
1717 | print_generic_expr (file, db_p->var, dump_flags); | |
1718 | bitmap_print (file, db_p->def_blocks, ", DEF_BLOCKS: { ", "}"); | |
1719 | bitmap_print (file, db_p->livein_blocks, ", LIVEIN_BLOCKS: { ", "}"); | |
1720 | bitmap_print (file, db_p->phi_blocks, ", PHI_BLOCKS: { ", "}\n"); | |
6de9cd9a | 1721 | |
7256233c DN |
1722 | return 1; |
1723 | } | |
6de9cd9a | 1724 | |
6de9cd9a | 1725 | |
38635499 DN |
1726 | /* Dump the DEF_BLOCKS hash table on FILE. */ |
1727 | ||
1728 | void | |
1729 | dump_def_blocks (FILE *file) | |
1730 | { | |
1731 | fprintf (file, "\n\nDefinition and live-in blocks:\n\n"); | |
1732 | if (def_blocks) | |
1733 | htab_traverse (def_blocks, debug_def_blocks_r, file); | |
1734 | } | |
1735 | ||
1736 | ||
7256233c | 1737 | /* Dump the DEF_BLOCKS hash table on stderr. */ |
6de9cd9a | 1738 | |
24e47c76 | 1739 | DEBUG_FUNCTION void |
7256233c DN |
1740 | debug_def_blocks (void) |
1741 | { | |
38635499 | 1742 | dump_def_blocks (stderr); |
7256233c | 1743 | } |
6de9cd9a | 1744 | |
5f240ec4 | 1745 | |
0bca51f0 | 1746 | /* Register NEW_NAME to be the new reaching definition for OLD_NAME. */ |
6de9cd9a | 1747 | |
0bca51f0 DN |
1748 | static inline void |
1749 | register_new_update_single (tree new_name, tree old_name) | |
1750 | { | |
1751 | tree currdef = get_current_def (old_name); | |
5f240ec4 | 1752 | |
38635499 | 1753 | /* Push the current reaching definition into BLOCK_DEFS_STACK. |
0bca51f0 DN |
1754 | This stack is later used by the dominator tree callbacks to |
1755 | restore the reaching definitions for all the variables | |
1756 | defined in the block after a recursive visit to all its | |
1757 | immediately dominated blocks. */ | |
d4e6fecb NS |
1758 | VEC_reserve (tree, heap, block_defs_stack, 2); |
1759 | VEC_quick_push (tree, block_defs_stack, currdef); | |
1760 | VEC_quick_push (tree, block_defs_stack, old_name); | |
5f240ec4 | 1761 | |
0bca51f0 DN |
1762 | /* Set the current reaching definition for OLD_NAME to be |
1763 | NEW_NAME. */ | |
1764 | set_current_def (old_name, new_name); | |
1765 | } | |
7256233c | 1766 | |
6de9cd9a | 1767 | |
0bca51f0 DN |
1768 | /* Register NEW_NAME to be the new reaching definition for all the |
1769 | names in OLD_NAMES. Used by the incremental SSA update routines to | |
1770 | replace old SSA names with new ones. */ | |
7256233c | 1771 | |
0bca51f0 DN |
1772 | static inline void |
1773 | register_new_update_set (tree new_name, bitmap old_names) | |
1774 | { | |
1775 | bitmap_iterator bi; | |
1776 | unsigned i; | |
7256233c | 1777 | |
0bca51f0 DN |
1778 | EXECUTE_IF_SET_IN_BITMAP (old_names, 0, i, bi) |
1779 | register_new_update_single (new_name, ssa_name (i)); | |
6de9cd9a DN |
1780 | } |
1781 | ||
7256233c | 1782 | |
0bca51f0 | 1783 | |
84d65814 DN |
1784 | /* If the operand pointed to by USE_P is a name in OLD_SSA_NAMES or |
1785 | it is a symbol marked for renaming, replace it with USE_P's current | |
1786 | reaching definition. */ | |
1787 | ||
1788 | static inline void | |
1789 | maybe_replace_use (use_operand_p use_p) | |
1790 | { | |
1791 | tree rdef = NULL_TREE; | |
1792 | tree use = USE_FROM_PTR (use_p); | |
1793 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); | |
1794 | ||
1795 | if (symbol_marked_for_renaming (sym)) | |
1796 | rdef = get_reaching_def (sym); | |
1797 | else if (is_old_name (use)) | |
1798 | rdef = get_reaching_def (use); | |
1799 | ||
1800 | if (rdef && rdef != use) | |
1801 | SET_USE (use_p, rdef); | |
1802 | } | |
1803 | ||
1804 | ||
b5b8b0ac AO |
1805 | /* Same as maybe_replace_use, but without introducing default stmts, |
1806 | returning false to indicate a need to do so. */ | |
1807 | ||
1808 | static inline bool | |
1809 | maybe_replace_use_in_debug_stmt (use_operand_p use_p) | |
1810 | { | |
1811 | tree rdef = NULL_TREE; | |
1812 | tree use = USE_FROM_PTR (use_p); | |
1813 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); | |
1814 | ||
1815 | if (symbol_marked_for_renaming (sym)) | |
1816 | rdef = get_current_def (sym); | |
1817 | else if (is_old_name (use)) | |
1818 | { | |
1819 | rdef = get_current_def (use); | |
1820 | /* We can't assume that, if there's no current definition, the | |
1821 | default one should be used. It could be the case that we've | |
1822 | rearranged blocks so that the earlier definition no longer | |
1823 | dominates the use. */ | |
1824 | if (!rdef && SSA_NAME_IS_DEFAULT_DEF (use)) | |
1825 | rdef = use; | |
1826 | } | |
1827 | else | |
1828 | rdef = use; | |
1829 | ||
1830 | if (rdef && rdef != use) | |
1831 | SET_USE (use_p, rdef); | |
1832 | ||
1833 | return rdef != NULL_TREE; | |
1834 | } | |
1835 | ||
1836 | ||
84d65814 DN |
1837 | /* If the operand pointed to by DEF_P is an SSA name in NEW_SSA_NAMES |
1838 | or OLD_SSA_NAMES, or if it is a symbol marked for renaming, | |
1839 | register it as the current definition for the names replaced by | |
1840 | DEF_P. */ | |
1841 | ||
1842 | static inline void | |
3a56edc7 AO |
1843 | maybe_register_def (def_operand_p def_p, gimple stmt, |
1844 | gimple_stmt_iterator gsi) | |
84d65814 DN |
1845 | { |
1846 | tree def = DEF_FROM_PTR (def_p); | |
1847 | tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def); | |
1848 | ||
38635499 DN |
1849 | /* If DEF is a naked symbol that needs renaming, create a new |
1850 | name for it. */ | |
84d65814 DN |
1851 | if (symbol_marked_for_renaming (sym)) |
1852 | { | |
1853 | if (DECL_P (def)) | |
1854 | { | |
3a56edc7 AO |
1855 | tree tracked_var; |
1856 | ||
84d65814 DN |
1857 | def = make_ssa_name (def, stmt); |
1858 | SET_DEF (def_p, def); | |
3a56edc7 AO |
1859 | |
1860 | tracked_var = target_for_debug_bind (sym); | |
1861 | if (tracked_var) | |
1862 | { | |
1863 | gimple note = gimple_build_debug_bind (tracked_var, def, stmt); | |
c47987fa JJ |
1864 | /* If stmt ends the bb, insert the debug stmt on the single |
1865 | non-EH edge from the stmt. */ | |
1866 | if (gsi_one_before_end_p (gsi) && stmt_ends_bb_p (stmt)) | |
1867 | { | |
1868 | basic_block bb = gsi_bb (gsi); | |
1869 | edge_iterator ei; | |
1870 | edge e, ef = NULL; | |
1871 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1872 | if (!(e->flags & EDGE_EH)) | |
1873 | { | |
1874 | gcc_assert (!ef); | |
1875 | ef = e; | |
1876 | } | |
1877 | gcc_assert (ef | |
1878 | && single_pred_p (ef->dest) | |
1879 | && !phi_nodes (ef->dest) | |
1880 | && ef->dest != EXIT_BLOCK_PTR); | |
1881 | gsi_insert_on_edge_immediate (ef, note); | |
1882 | } | |
1883 | else | |
1884 | gsi_insert_after (&gsi, note, GSI_SAME_STMT); | |
3a56edc7 | 1885 | } |
84d65814 DN |
1886 | } |
1887 | ||
1888 | register_new_update_single (def, sym); | |
1889 | } | |
1890 | else | |
1891 | { | |
1892 | /* If DEF is a new name, register it as a new definition | |
1893 | for all the names replaced by DEF. */ | |
1894 | if (is_new_name (def)) | |
1895 | register_new_update_set (def, names_replaced_by (def)); | |
1896 | ||
1897 | /* If DEF is an old name, register DEF as a new | |
1898 | definition for itself. */ | |
1899 | if (is_old_name (def)) | |
1900 | register_new_update_single (def, def); | |
1901 | } | |
1902 | } | |
1903 | ||
1904 | ||
0bca51f0 DN |
1905 | /* Update every variable used in the statement pointed-to by SI. The |
1906 | statement is assumed to be in SSA form already. Names in | |
1907 | OLD_SSA_NAMES used by SI will be updated to their current reaching | |
1908 | definition. Names in OLD_SSA_NAMES or NEW_SSA_NAMES defined by SI | |
1909 | will be registered as a new definition for their corresponding name | |
1910 | in OLD_SSA_NAMES. */ | |
1911 | ||
1912 | static void | |
3a56edc7 | 1913 | rewrite_update_stmt (gimple stmt, gimple_stmt_iterator gsi) |
0bca51f0 | 1914 | { |
0bca51f0 DN |
1915 | use_operand_p use_p; |
1916 | def_operand_p def_p; | |
1917 | ssa_op_iter iter; | |
1918 | ||
0bca51f0 | 1919 | /* Only update marked statements. */ |
726a989a | 1920 | if (!rewrite_uses_p (stmt) && !register_defs_p (stmt)) |
0bca51f0 DN |
1921 | return; |
1922 | ||
1923 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1924 | { | |
1925 | fprintf (dump_file, "Updating SSA information for statement "); | |
726a989a | 1926 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); |
0bca51f0 DN |
1927 | fprintf (dump_file, "\n"); |
1928 | } | |
1929 | ||
1930 | /* Rewrite USES included in OLD_SSA_NAMES and USES whose underlying | |
1931 | symbol is marked for renaming. */ | |
726a989a | 1932 | if (rewrite_uses_p (stmt)) |
b5b8b0ac AO |
1933 | { |
1934 | if (is_gimple_debug (stmt)) | |
1935 | { | |
1936 | bool failed = false; | |
1937 | ||
1938 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) | |
1939 | if (!maybe_replace_use_in_debug_stmt (use_p)) | |
1940 | { | |
1941 | failed = true; | |
1942 | break; | |
1943 | } | |
1944 | ||
1945 | if (failed) | |
1946 | { | |
1947 | /* DOM sometimes threads jumps in such a way that a | |
1948 | debug stmt ends up referencing a SSA variable that no | |
1949 | longer dominates the debug stmt, but such that all | |
1950 | incoming definitions refer to the same definition in | |
1951 | an earlier dominator. We could try to recover that | |
1952 | definition somehow, but this will have to do for now. | |
1953 | ||
1954 | Introducing a default definition, which is what | |
1955 | maybe_replace_use() would do in such cases, may | |
1956 | modify code generation, for the otherwise-unused | |
1957 | default definition would never go away, modifying SSA | |
1958 | version numbers all over. */ | |
1959 | gimple_debug_bind_reset_value (stmt); | |
1960 | update_stmt (stmt); | |
1961 | } | |
1962 | } | |
1963 | else | |
1964 | { | |
1965 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) | |
1966 | maybe_replace_use (use_p); | |
1967 | } | |
1968 | } | |
0bca51f0 DN |
1969 | |
1970 | /* Register definitions of names in NEW_SSA_NAMES and OLD_SSA_NAMES. | |
1971 | Also register definitions for names whose underlying symbol is | |
1972 | marked for renaming. */ | |
726a989a | 1973 | if (register_defs_p (stmt)) |
5006671f | 1974 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_ALL_DEFS) |
3a56edc7 | 1975 | maybe_register_def (def_p, stmt, gsi); |
0bca51f0 DN |
1976 | } |
1977 | ||
1978 | ||
1979 | /* Visit all the successor blocks of BB looking for PHI nodes. For | |
1980 | every PHI node found, check if any of its arguments is in | |
1981 | OLD_SSA_NAMES. If so, and if the argument has a current reaching | |
1982 | definition, replace it. */ | |
1983 | ||
1984 | static void | |
ccf5c864 | 1985 | rewrite_update_phi_arguments (basic_block bb) |
0bca51f0 DN |
1986 | { |
1987 | edge e; | |
1988 | edge_iterator ei; | |
2ce79879 | 1989 | unsigned i; |
0bca51f0 DN |
1990 | |
1991 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1992 | { | |
726a989a RB |
1993 | gimple phi; |
1994 | gimple_vec phis; | |
0bca51f0 | 1995 | |
2ce79879 ZD |
1996 | if (!bitmap_bit_p (blocks_with_phis_to_rewrite, e->dest->index)) |
1997 | continue; | |
b8698a0f | 1998 | |
726a989a RB |
1999 | phis = VEC_index (gimple_vec, phis_to_rewrite, e->dest->index); |
2000 | for (i = 0; VEC_iterate (gimple, phis, i, phi); i++) | |
0bca51f0 | 2001 | { |
f5045c96 | 2002 | tree arg, lhs_sym, reaching_def = NULL; |
0bca51f0 DN |
2003 | use_operand_p arg_p; |
2004 | ||
726a989a | 2005 | gcc_assert (rewrite_uses_p (phi)); |
0bca51f0 DN |
2006 | |
2007 | arg_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e); | |
2008 | arg = USE_FROM_PTR (arg_p); | |
2009 | ||
2010 | if (arg && !DECL_P (arg) && TREE_CODE (arg) != SSA_NAME) | |
2011 | continue; | |
2012 | ||
726a989a | 2013 | lhs_sym = SSA_NAME_VAR (gimple_phi_result (phi)); |
38635499 | 2014 | |
0bca51f0 DN |
2015 | if (arg == NULL_TREE) |
2016 | { | |
2017 | /* When updating a PHI node for a recently introduced | |
2018 | symbol we may find NULL arguments. That's why we | |
2019 | take the symbol from the LHS of the PHI node. */ | |
f5045c96 AM |
2020 | reaching_def = get_reaching_def (lhs_sym); |
2021 | ||
0bca51f0 DN |
2022 | } |
2023 | else | |
2024 | { | |
2025 | tree sym = DECL_P (arg) ? arg : SSA_NAME_VAR (arg); | |
2026 | ||
2027 | if (symbol_marked_for_renaming (sym)) | |
f5045c96 | 2028 | reaching_def = get_reaching_def (sym); |
0bca51f0 | 2029 | else if (is_old_name (arg)) |
f5045c96 AM |
2030 | reaching_def = get_reaching_def (arg); |
2031 | } | |
2032 | ||
2033 | /* Update the argument if there is a reaching def. */ | |
2034 | if (reaching_def) | |
2035 | { | |
2036 | gimple stmt; | |
2037 | source_location locus; | |
2038 | int arg_i = PHI_ARG_INDEX_FROM_USE (arg_p); | |
2039 | ||
2040 | SET_USE (arg_p, reaching_def); | |
2041 | stmt = SSA_NAME_DEF_STMT (reaching_def); | |
2042 | ||
b8698a0f | 2043 | /* Single element PHI nodes behave like copies, so get the |
f5045c96 | 2044 | location from the phi argument. */ |
b8698a0f | 2045 | if (gimple_code (stmt) == GIMPLE_PHI && |
f5045c96 AM |
2046 | gimple_phi_num_args (stmt) == 1) |
2047 | locus = gimple_phi_arg_location (stmt, 0); | |
2048 | else | |
2049 | locus = gimple_location (stmt); | |
2050 | ||
2051 | gimple_phi_arg_set_location (phi, arg_i, locus); | |
0bca51f0 DN |
2052 | } |
2053 | ||
f5045c96 | 2054 | |
0bca51f0 DN |
2055 | if (e->flags & EDGE_ABNORMAL) |
2056 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (arg_p)) = 1; | |
2057 | } | |
2058 | } | |
2059 | } | |
2060 | ||
2061 | ||
ccf5c864 PB |
2062 | /* Initialization of block data structures for the incremental SSA |
2063 | update pass. Create a block local stack of reaching definitions | |
2064 | for new SSA names produced in this block (BLOCK_DEFS). Register | |
2065 | new definitions for every PHI node in the block. */ | |
2066 | ||
2067 | static void | |
2068 | rewrite_update_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
2069 | basic_block bb) | |
2070 | { | |
2071 | edge e; | |
2072 | edge_iterator ei; | |
2073 | bool is_abnormal_phi; | |
2074 | gimple_stmt_iterator gsi; | |
2075 | ||
2076 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2077 | fprintf (dump_file, "\n\nRegistering new PHI nodes in block #%d\n\n", | |
2078 | bb->index); | |
2079 | ||
2080 | /* Mark the unwind point for this block. */ | |
2081 | VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE); | |
2082 | ||
2083 | if (!bitmap_bit_p (blocks_to_update, bb->index)) | |
2084 | return; | |
2085 | ||
2086 | /* Mark the LHS if any of the arguments flows through an abnormal | |
2087 | edge. */ | |
2088 | is_abnormal_phi = false; | |
2089 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2090 | if (e->flags & EDGE_ABNORMAL) | |
2091 | { | |
2092 | is_abnormal_phi = true; | |
2093 | break; | |
2094 | } | |
2095 | ||
2096 | /* If any of the PHI nodes is a replacement for a name in | |
2097 | OLD_SSA_NAMES or it's one of the names in NEW_SSA_NAMES, then | |
2098 | register it as a new definition for its corresponding name. Also | |
2099 | register definitions for names whose underlying symbols are | |
2100 | marked for renaming. */ | |
2101 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2102 | { | |
2103 | tree lhs, lhs_sym; | |
2104 | gimple phi = gsi_stmt (gsi); | |
2105 | ||
2106 | if (!register_defs_p (phi)) | |
2107 | continue; | |
b8698a0f | 2108 | |
ccf5c864 PB |
2109 | lhs = gimple_phi_result (phi); |
2110 | lhs_sym = SSA_NAME_VAR (lhs); | |
2111 | ||
2112 | if (symbol_marked_for_renaming (lhs_sym)) | |
2113 | register_new_update_single (lhs, lhs_sym); | |
2114 | else | |
2115 | { | |
2116 | ||
2117 | /* If LHS is a new name, register a new definition for all | |
2118 | the names replaced by LHS. */ | |
2119 | if (is_new_name (lhs)) | |
2120 | register_new_update_set (lhs, names_replaced_by (lhs)); | |
b8698a0f | 2121 | |
ccf5c864 PB |
2122 | /* If LHS is an OLD name, register it as a new definition |
2123 | for itself. */ | |
2124 | if (is_old_name (lhs)) | |
2125 | register_new_update_single (lhs, lhs); | |
2126 | } | |
2127 | ||
2128 | if (is_abnormal_phi) | |
2129 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs) = 1; | |
2130 | } | |
2131 | ||
2132 | /* Step 2. Rewrite every variable used in each statement in the block. */ | |
2133 | if (TEST_BIT (interesting_blocks, bb->index)) | |
3a56edc7 AO |
2134 | { |
2135 | gcc_assert (bitmap_bit_p (blocks_to_update, bb->index)); | |
ccf5c864 | 2136 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
3a56edc7 AO |
2137 | rewrite_update_stmt (gsi_stmt (gsi), gsi); |
2138 | } | |
ccf5c864 PB |
2139 | |
2140 | /* Step 3. Update PHI nodes. */ | |
2141 | rewrite_update_phi_arguments (bb); | |
2142 | } | |
2143 | ||
2144 | /* Called after visiting block BB. Unwind BLOCK_DEFS_STACK to restore | |
2145 | the current reaching definition of every name re-written in BB to | |
2146 | the original reaching definition before visiting BB. This | |
2147 | unwinding must be done in the opposite order to what is done in | |
2148 | register_new_update_set. */ | |
2149 | ||
2150 | static void | |
2151 | rewrite_update_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
2152 | basic_block bb ATTRIBUTE_UNUSED) | |
2153 | { | |
2154 | while (VEC_length (tree, block_defs_stack) > 0) | |
2155 | { | |
2156 | tree var = VEC_pop (tree, block_defs_stack); | |
2157 | tree saved_def; | |
b8698a0f | 2158 | |
ccf5c864 PB |
2159 | /* NULL indicates the unwind stop point for this block (see |
2160 | rewrite_update_enter_block). */ | |
2161 | if (var == NULL) | |
2162 | return; | |
2163 | ||
2164 | saved_def = VEC_pop (tree, block_defs_stack); | |
2165 | set_current_def (var, saved_def); | |
2166 | } | |
2167 | } | |
2168 | ||
2169 | ||
0bca51f0 | 2170 | /* Rewrite the actual blocks, statements, and PHI arguments, to be in SSA |
b8698a0f | 2171 | form. |
0bca51f0 DN |
2172 | |
2173 | ENTRY indicates the block where to start. Every block dominated by | |
2174 | ENTRY will be rewritten. | |
2175 | ||
2176 | WHAT indicates what actions will be taken by the renamer (see enum | |
2177 | rewrite_mode). | |
2178 | ||
2179 | BLOCKS are the set of interesting blocks for the dominator walker | |
2180 | to process. If this set is NULL, then all the nodes dominated | |
2181 | by ENTRY are walked. Otherwise, blocks dominated by ENTRY that | |
2182 | are not present in BLOCKS are ignored. */ | |
2183 | ||
2184 | static void | |
ccf5c864 | 2185 | rewrite_blocks (basic_block entry, enum rewrite_mode what) |
0bca51f0 DN |
2186 | { |
2187 | struct dom_walk_data walk_data; | |
b8698a0f | 2188 | |
0bca51f0 DN |
2189 | /* Rewrite all the basic blocks in the program. */ |
2190 | timevar_push (TV_TREE_SSA_REWRITE_BLOCKS); | |
2191 | ||
2192 | /* Setup callbacks for the generic dominator tree walker. */ | |
2193 | memset (&walk_data, 0, sizeof (walk_data)); | |
2194 | ||
2195 | walk_data.dom_direction = CDI_DOMINATORS; | |
0bca51f0 DN |
2196 | |
2197 | if (what == REWRITE_ALL) | |
ccf5c864 PB |
2198 | { |
2199 | walk_data.before_dom_children = rewrite_enter_block; | |
2200 | walk_data.after_dom_children = rewrite_leave_block; | |
2201 | } | |
0bca51f0 | 2202 | else if (what == REWRITE_UPDATE) |
ccf5c864 PB |
2203 | { |
2204 | walk_data.before_dom_children = rewrite_update_enter_block; | |
2205 | walk_data.after_dom_children = rewrite_update_leave_block; | |
2206 | } | |
0bca51f0 DN |
2207 | else |
2208 | gcc_unreachable (); | |
2209 | ||
d4e6fecb | 2210 | block_defs_stack = VEC_alloc (tree, heap, 10); |
0bca51f0 DN |
2211 | |
2212 | /* Initialize the dominator walker. */ | |
2213 | init_walk_dominator_tree (&walk_data); | |
2214 | ||
2215 | /* Recursively walk the dominator tree rewriting each statement in | |
2216 | each basic block. */ | |
2217 | walk_dominator_tree (&walk_data, entry); | |
2218 | ||
2219 | /* Finalize the dominator walker. */ | |
2220 | fini_walk_dominator_tree (&walk_data); | |
2221 | ||
2222 | /* Debugging dumps. */ | |
2223 | if (dump_file && (dump_flags & TDF_STATS)) | |
2224 | { | |
2225 | dump_dfa_stats (dump_file); | |
2226 | if (def_blocks) | |
2227 | dump_tree_ssa_stats (dump_file); | |
2228 | } | |
b8698a0f | 2229 | |
d4e6fecb | 2230 | VEC_free (tree, heap, block_defs_stack); |
0bca51f0 DN |
2231 | |
2232 | timevar_pop (TV_TREE_SSA_REWRITE_BLOCKS); | |
2233 | } | |
2234 | ||
2235 | ||
ccf5c864 PB |
2236 | /* Block processing routine for mark_def_sites. Clear the KILLS bitmap |
2237 | at the start of each block, and call mark_def_sites for each statement. */ | |
6de9cd9a | 2238 | |
5f240ec4 | 2239 | static void |
ccf5c864 | 2240 | mark_def_sites_block (struct dom_walk_data *walk_data, basic_block bb) |
5f240ec4 | 2241 | { |
38635499 | 2242 | struct mark_def_sites_global_data *gd; |
ccf5c864 PB |
2243 | bitmap kills; |
2244 | gimple_stmt_iterator gsi; | |
2245 | ||
38635499 | 2246 | gd = (struct mark_def_sites_global_data *) walk_data->global_data; |
ccf5c864 PB |
2247 | kills = gd->kills; |
2248 | ||
2249 | bitmap_clear (kills); | |
2250 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2251 | mark_def_sites (bb, gsi_stmt (gsi), kills); | |
7256233c | 2252 | } |
5f240ec4 | 2253 | |
5f240ec4 | 2254 | |
0bca51f0 DN |
2255 | /* Mark the definition site blocks for each variable, so that we know |
2256 | where the variable is actually live. | |
2257 | ||
ccf5c864 PB |
2258 | The INTERESTING_BLOCKS global will be filled in with all the blocks |
2259 | that should be processed by the renamer. It is assumed that the | |
2260 | caller has already initialized and zeroed it. */ | |
5f240ec4 | 2261 | |
0bca51f0 | 2262 | static void |
ccf5c864 | 2263 | mark_def_site_blocks (void) |
7256233c | 2264 | { |
7256233c DN |
2265 | struct dom_walk_data walk_data; |
2266 | struct mark_def_sites_global_data mark_def_sites_global_data; | |
5f240ec4 | 2267 | |
7256233c DN |
2268 | /* Setup callbacks for the generic dominator tree walker to find and |
2269 | mark definition sites. */ | |
7256233c DN |
2270 | walk_data.dom_direction = CDI_DOMINATORS; |
2271 | walk_data.initialize_block_local_data = NULL; | |
ccf5c864 PB |
2272 | walk_data.before_dom_children = mark_def_sites_block; |
2273 | walk_data.after_dom_children = NULL; | |
5f240ec4 | 2274 | |
7256233c DN |
2275 | /* Notice that this bitmap is indexed using variable UIDs, so it must be |
2276 | large enough to accommodate all the variables referenced in the | |
2277 | function, not just the ones we are renaming. */ | |
2278 | mark_def_sites_global_data.kills = BITMAP_ALLOC (NULL); | |
2279 | walk_data.global_data = &mark_def_sites_global_data; | |
6de9cd9a | 2280 | |
7256233c DN |
2281 | /* We do not have any local data. */ |
2282 | walk_data.block_local_data_size = 0; | |
2283 | ||
2284 | /* Initialize the dominator walker. */ | |
2285 | init_walk_dominator_tree (&walk_data); | |
2286 | ||
2287 | /* Recursively walk the dominator tree. */ | |
2288 | walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR); | |
2289 | ||
2290 | /* Finalize the dominator walker. */ | |
2291 | fini_walk_dominator_tree (&walk_data); | |
2292 | ||
2293 | /* We no longer need this bitmap, clear and free it. */ | |
2294 | BITMAP_FREE (mark_def_sites_global_data.kills); | |
6de9cd9a DN |
2295 | } |
2296 | ||
6de9cd9a | 2297 | |
38635499 DN |
2298 | /* Initialize internal data needed during renaming. */ |
2299 | ||
2300 | static void | |
2301 | init_ssa_renamer (void) | |
2302 | { | |
2303 | tree var; | |
2304 | referenced_var_iterator rvi; | |
2305 | ||
2306 | cfun->gimple_df->in_ssa_p = false; | |
2307 | ||
2308 | /* Allocate memory for the DEF_BLOCKS hash table. */ | |
2309 | gcc_assert (def_blocks == NULL); | |
2310 | def_blocks = htab_create (num_referenced_vars, def_blocks_hash, | |
2311 | def_blocks_eq, def_blocks_free); | |
2312 | ||
2313 | FOR_EACH_REFERENCED_VAR(var, rvi) | |
2314 | set_current_def (var, NULL_TREE); | |
2315 | } | |
2316 | ||
2317 | ||
2318 | /* Deallocate internal data structures used by the renamer. */ | |
2319 | ||
2320 | static void | |
2321 | fini_ssa_renamer (void) | |
2322 | { | |
2323 | if (def_blocks) | |
2324 | { | |
2325 | htab_delete (def_blocks); | |
2326 | def_blocks = NULL; | |
2327 | } | |
2328 | ||
2329 | cfun->gimple_df->in_ssa_p = true; | |
2330 | } | |
2331 | ||
7256233c | 2332 | /* Main entry point into the SSA builder. The renaming process |
0bca51f0 | 2333 | proceeds in four main phases: |
6de9cd9a | 2334 | |
0bca51f0 DN |
2335 | 1- Compute dominance frontier and immediate dominators, needed to |
2336 | insert PHI nodes and rename the function in dominator tree | |
2337 | order. | |
6de9cd9a | 2338 | |
0bca51f0 | 2339 | 2- Find and mark all the blocks that define variables |
7256233c | 2340 | (mark_def_site_blocks). |
6de9cd9a | 2341 | |
0bca51f0 | 2342 | 3- Insert PHI nodes at dominance frontiers (insert_phi_nodes). |
6de9cd9a | 2343 | |
0bca51f0 | 2344 | 4- Rename all the blocks (rewrite_blocks) and statements in the program. |
6de9cd9a | 2345 | |
77bfa778 | 2346 | Steps 3 and 4 are done using the dominator tree walker |
0bca51f0 | 2347 | (walk_dominator_tree). */ |
7256233c | 2348 | |
c2924966 | 2349 | static unsigned int |
0bca51f0 | 2350 | rewrite_into_ssa (void) |
6de9cd9a | 2351 | { |
0fc555fb | 2352 | bitmap_head *dfs; |
7256233c | 2353 | basic_block bb; |
b8698a0f | 2354 | |
7256233c | 2355 | timevar_push (TV_TREE_SSA_OTHER); |
6de9cd9a | 2356 | |
0bca51f0 DN |
2357 | /* Initialize operand data structures. */ |
2358 | init_ssa_operands (); | |
6de9cd9a | 2359 | |
38635499 DN |
2360 | /* Initialize internal data needed by the renamer. */ |
2361 | init_ssa_renamer (); | |
2362 | ||
0bca51f0 DN |
2363 | /* Initialize the set of interesting blocks. The callback |
2364 | mark_def_sites will add to this set those blocks that the renamer | |
2365 | should process. */ | |
2366 | interesting_blocks = sbitmap_alloc (last_basic_block); | |
2367 | sbitmap_zero (interesting_blocks); | |
6de9cd9a | 2368 | |
af5d3a18 | 2369 | /* Initialize dominance frontier. */ |
0fc555fb | 2370 | dfs = XNEWVEC (bitmap_head, last_basic_block); |
7256233c | 2371 | FOR_EACH_BB (bb) |
0fc555fb | 2372 | bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack); |
6de9cd9a | 2373 | |
0bca51f0 DN |
2374 | /* 1- Compute dominance frontiers. */ |
2375 | calculate_dominance_info (CDI_DOMINATORS); | |
7256233c | 2376 | compute_dominance_frontiers (dfs); |
6de9cd9a | 2377 | |
0bca51f0 | 2378 | /* 2- Find and mark definition sites. */ |
ccf5c864 | 2379 | mark_def_site_blocks (); |
0bca51f0 DN |
2380 | |
2381 | /* 3- Insert PHI nodes at dominance frontiers of definition blocks. */ | |
84d65814 | 2382 | insert_phi_nodes (dfs); |
6de9cd9a | 2383 | |
0bca51f0 | 2384 | /* 4- Rename all the blocks. */ |
ccf5c864 | 2385 | rewrite_blocks (ENTRY_BLOCK_PTR, REWRITE_ALL); |
6de9cd9a | 2386 | |
7256233c DN |
2387 | /* Free allocated memory. */ |
2388 | FOR_EACH_BB (bb) | |
0fc555fb | 2389 | bitmap_clear (&dfs[bb->index]); |
7256233c | 2390 | free (dfs); |
6de9cd9a | 2391 | |
b5dcb2b9 JL |
2392 | sbitmap_free (interesting_blocks); |
2393 | ||
38635499 DN |
2394 | fini_ssa_renamer (); |
2395 | ||
7256233c | 2396 | timevar_pop (TV_TREE_SSA_OTHER); |
c2924966 | 2397 | return 0; |
6de9cd9a DN |
2398 | } |
2399 | ||
2400 | ||
b8698a0f | 2401 | struct gimple_opt_pass pass_build_ssa = |
6de9cd9a | 2402 | { |
8ddbbcae JH |
2403 | { |
2404 | GIMPLE_PASS, | |
7256233c DN |
2405 | "ssa", /* name */ |
2406 | NULL, /* gate */ | |
0bca51f0 | 2407 | rewrite_into_ssa, /* execute */ |
7256233c DN |
2408 | NULL, /* sub */ |
2409 | NULL, /* next */ | |
2410 | 0, /* static_pass_number */ | |
7072a650 | 2411 | TV_NONE, /* tv_id */ |
7256233c DN |
2412 | PROP_cfg | PROP_referenced_vars, /* properties_required */ |
2413 | PROP_ssa, /* properties_provided */ | |
2414 | 0, /* properties_destroyed */ | |
2415 | 0, /* todo_flags_start */ | |
3f519b35 | 2416 | TODO_dump_func |
5006671f | 2417 | | TODO_update_ssa_only_virtuals |
3f519b35 | 2418 | | TODO_verify_ssa |
8ddbbcae JH |
2419 | | TODO_remove_unused_locals /* todo_flags_finish */ |
2420 | } | |
7256233c | 2421 | }; |
6de9cd9a DN |
2422 | |
2423 | ||
0bca51f0 DN |
2424 | /* Mark the definition of VAR at STMT and BB as interesting for the |
2425 | renamer. BLOCKS is the set of blocks that need updating. */ | |
6de9cd9a | 2426 | |
0bca51f0 | 2427 | static void |
726a989a | 2428 | mark_def_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p) |
6de9cd9a | 2429 | { |
95dd3097 | 2430 | gcc_assert (bitmap_bit_p (blocks_to_update, bb->index)); |
726a989a | 2431 | set_register_defs (stmt, true); |
0bca51f0 DN |
2432 | |
2433 | if (insert_phi_p) | |
2434 | { | |
726a989a | 2435 | bool is_phi_p = gimple_code (stmt) == GIMPLE_PHI; |
0bca51f0 | 2436 | |
0bca51f0 DN |
2437 | set_def_block (var, bb, is_phi_p); |
2438 | ||
2439 | /* If VAR is an SSA name in NEW_SSA_NAMES, this is a definition | |
2440 | site for both itself and all the old names replaced by it. */ | |
2441 | if (TREE_CODE (var) == SSA_NAME && is_new_name (var)) | |
2442 | { | |
2443 | bitmap_iterator bi; | |
2444 | unsigned i; | |
2445 | bitmap set = names_replaced_by (var); | |
2446 | if (set) | |
2447 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) | |
2448 | set_def_block (ssa_name (i), bb, is_phi_p); | |
2449 | } | |
2450 | } | |
2451 | } | |
2452 | ||
2453 | ||
2454 | /* Mark the use of VAR at STMT and BB as interesting for the | |
2455 | renamer. INSERT_PHI_P is true if we are going to insert new PHI | |
95dd3097 | 2456 | nodes. */ |
0bca51f0 DN |
2457 | |
2458 | static inline void | |
726a989a | 2459 | mark_use_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p) |
0bca51f0 | 2460 | { |
726a989a | 2461 | basic_block def_bb = gimple_bb (stmt); |
2ce79879 | 2462 | |
95dd3097 ZD |
2463 | mark_block_for_update (def_bb); |
2464 | mark_block_for_update (bb); | |
2465 | ||
726a989a | 2466 | if (gimple_code (stmt) == GIMPLE_PHI) |
2ce79879 ZD |
2467 | mark_phi_for_rewrite (def_bb, stmt); |
2468 | else | |
b5b8b0ac AO |
2469 | { |
2470 | set_rewrite_uses (stmt, true); | |
2471 | ||
2472 | if (is_gimple_debug (stmt)) | |
2473 | return; | |
2474 | } | |
0bca51f0 DN |
2475 | |
2476 | /* If VAR has not been defined in BB, then it is live-on-entry | |
2477 | to BB. Note that we cannot just use the block holding VAR's | |
2478 | definition because if VAR is one of the names in OLD_SSA_NAMES, | |
2479 | it will have several definitions (itself and all the names that | |
2480 | replace it). */ | |
2481 | if (insert_phi_p) | |
2482 | { | |
84d65814 | 2483 | struct def_blocks_d *db_p = get_def_blocks_for (var); |
0bca51f0 DN |
2484 | if (!bitmap_bit_p (db_p->def_blocks, bb->index)) |
2485 | set_livein_block (var, bb); | |
2486 | } | |
2487 | } | |
2488 | ||
2489 | ||
0bca51f0 | 2490 | /* Do a dominator walk starting at BB processing statements that |
84d65814 DN |
2491 | reference symbols in SYMS_TO_RENAME. This is very similar to |
2492 | mark_def_sites, but the scan handles statements whose operands may | |
95dd3097 | 2493 | already be SSA names. |
0bca51f0 | 2494 | |
84d65814 DN |
2495 | If INSERT_PHI_P is true, mark those uses as live in the |
2496 | corresponding block. This is later used by the PHI placement | |
38635499 DN |
2497 | algorithm to make PHI pruning decisions. |
2498 | ||
2499 | FIXME. Most of this would be unnecessary if we could associate a | |
2500 | symbol to all the SSA names that reference it. But that | |
2501 | sounds like it would be expensive to maintain. Still, it | |
2502 | would be interesting to see if it makes better sense to do | |
2503 | that. */ | |
0bca51f0 DN |
2504 | |
2505 | static void | |
95dd3097 | 2506 | prepare_block_for_update (basic_block bb, bool insert_phi_p) |
0bca51f0 DN |
2507 | { |
2508 | basic_block son; | |
726a989a | 2509 | gimple_stmt_iterator si; |
f074ff6c ZD |
2510 | edge e; |
2511 | edge_iterator ei; | |
0bca51f0 | 2512 | |
95dd3097 ZD |
2513 | mark_block_for_update (bb); |
2514 | ||
0bca51f0 | 2515 | /* Process PHI nodes marking interesting those that define or use |
84d65814 | 2516 | the symbols that we are interested in. */ |
726a989a | 2517 | for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si)) |
0bca51f0 | 2518 | { |
726a989a RB |
2519 | gimple phi = gsi_stmt (si); |
2520 | tree lhs_sym, lhs = gimple_phi_result (phi); | |
0bca51f0 | 2521 | |
0bca51f0 DN |
2522 | lhs_sym = DECL_P (lhs) ? lhs : SSA_NAME_VAR (lhs); |
2523 | ||
f074ff6c ZD |
2524 | if (!symbol_marked_for_renaming (lhs_sym)) |
2525 | continue; | |
726a989a | 2526 | |
f074ff6c ZD |
2527 | mark_def_interesting (lhs_sym, phi, bb, insert_phi_p); |
2528 | ||
2529 | /* Mark the uses in phi nodes as interesting. It would be more correct | |
2530 | to process the arguments of the phi nodes of the successor edges of | |
2531 | BB at the end of prepare_block_for_update, however, that turns out | |
2532 | to be significantly more expensive. Doing it here is conservatively | |
2533 | correct -- it may only cause us to believe a value to be live in a | |
2534 | block that also contains its definition, and thus insert a few more | |
2535 | phi nodes for it. */ | |
2536 | FOR_EACH_EDGE (e, ei, bb->preds) | |
726a989a | 2537 | mark_use_interesting (lhs_sym, phi, e->src, insert_phi_p); |
0bca51f0 DN |
2538 | } |
2539 | ||
2540 | /* Process the statements. */ | |
726a989a | 2541 | for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) |
0bca51f0 | 2542 | { |
726a989a | 2543 | gimple stmt; |
0bca51f0 DN |
2544 | ssa_op_iter i; |
2545 | use_operand_p use_p; | |
2546 | def_operand_p def_p; | |
b8698a0f | 2547 | |
726a989a | 2548 | stmt = gsi_stmt (si); |
0bca51f0 | 2549 | |
38635499 | 2550 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, i, SSA_OP_ALL_USES) |
0bca51f0 DN |
2551 | { |
2552 | tree use = USE_FROM_PTR (use_p); | |
2553 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); | |
84d65814 | 2554 | if (symbol_marked_for_renaming (sym)) |
38635499 | 2555 | mark_use_interesting (sym, stmt, bb, insert_phi_p); |
0bca51f0 DN |
2556 | } |
2557 | ||
38635499 | 2558 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, i, SSA_OP_ALL_DEFS) |
0bca51f0 DN |
2559 | { |
2560 | tree def = DEF_FROM_PTR (def_p); | |
2561 | tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def); | |
0bca51f0 | 2562 | if (symbol_marked_for_renaming (sym)) |
38635499 | 2563 | mark_def_interesting (sym, stmt, bb, insert_phi_p); |
0bca51f0 DN |
2564 | } |
2565 | } | |
2566 | ||
2567 | /* Now visit all the blocks dominated by BB. */ | |
84d65814 | 2568 | for (son = first_dom_son (CDI_DOMINATORS, bb); |
38635499 DN |
2569 | son; |
2570 | son = next_dom_son (CDI_DOMINATORS, son)) | |
95dd3097 | 2571 | prepare_block_for_update (son, insert_phi_p); |
84d65814 DN |
2572 | } |
2573 | ||
2574 | ||
2575 | /* Helper for prepare_names_to_update. Mark all the use sites for | |
2576 | NAME as interesting. BLOCKS and INSERT_PHI_P are as in | |
2577 | prepare_names_to_update. */ | |
2578 | ||
2579 | static void | |
95dd3097 | 2580 | prepare_use_sites_for (tree name, bool insert_phi_p) |
84d65814 DN |
2581 | { |
2582 | use_operand_p use_p; | |
2583 | imm_use_iterator iter; | |
2584 | ||
2585 | FOR_EACH_IMM_USE_FAST (use_p, iter, name) | |
2586 | { | |
726a989a RB |
2587 | gimple stmt = USE_STMT (use_p); |
2588 | basic_block bb = gimple_bb (stmt); | |
84d65814 | 2589 | |
726a989a | 2590 | if (gimple_code (stmt) == GIMPLE_PHI) |
84d65814 | 2591 | { |
f074ff6c | 2592 | int ix = PHI_ARG_INDEX_FROM_USE (use_p); |
726a989a | 2593 | edge e = gimple_phi_arg_edge (stmt, ix); |
f074ff6c | 2594 | mark_use_interesting (name, stmt, e->src, insert_phi_p); |
84d65814 DN |
2595 | } |
2596 | else | |
2597 | { | |
2598 | /* For regular statements, mark this as an interesting use | |
2599 | for NAME. */ | |
95dd3097 | 2600 | mark_use_interesting (name, stmt, bb, insert_phi_p); |
84d65814 DN |
2601 | } |
2602 | } | |
0bca51f0 DN |
2603 | } |
2604 | ||
2605 | ||
84d65814 DN |
2606 | /* Helper for prepare_names_to_update. Mark the definition site for |
2607 | NAME as interesting. BLOCKS and INSERT_PHI_P are as in | |
2608 | prepare_names_to_update. */ | |
0bca51f0 DN |
2609 | |
2610 | static void | |
95dd3097 | 2611 | prepare_def_site_for (tree name, bool insert_phi_p) |
0bca51f0 | 2612 | { |
726a989a | 2613 | gimple stmt; |
0bca51f0 DN |
2614 | basic_block bb; |
2615 | ||
0bca51f0 DN |
2616 | gcc_assert (names_to_release == NULL |
2617 | || !bitmap_bit_p (names_to_release, SSA_NAME_VERSION (name))); | |
2618 | ||
2619 | stmt = SSA_NAME_DEF_STMT (name); | |
726a989a | 2620 | bb = gimple_bb (stmt); |
0bca51f0 DN |
2621 | if (bb) |
2622 | { | |
2623 | gcc_assert (bb->index < last_basic_block); | |
95dd3097 ZD |
2624 | mark_block_for_update (bb); |
2625 | mark_def_interesting (name, stmt, bb, insert_phi_p); | |
0bca51f0 DN |
2626 | } |
2627 | } | |
2628 | ||
2629 | ||
84d65814 | 2630 | /* Mark definition and use sites of names in NEW_SSA_NAMES and |
95dd3097 ZD |
2631 | OLD_SSA_NAMES. INSERT_PHI_P is true if the caller wants to insert |
2632 | PHI nodes for newly created names. */ | |
0bca51f0 DN |
2633 | |
2634 | static void | |
95dd3097 | 2635 | prepare_names_to_update (bool insert_phi_p) |
0bca51f0 | 2636 | { |
dfea6c85 | 2637 | unsigned i = 0; |
0bca51f0 | 2638 | bitmap_iterator bi; |
b6e7e9af | 2639 | sbitmap_iterator sbi; |
0bca51f0 DN |
2640 | |
2641 | /* If a name N from NEW_SSA_NAMES is also marked to be released, | |
2642 | remove it from NEW_SSA_NAMES so that we don't try to visit its | |
2643 | defining basic block (which most likely doesn't exist). Notice | |
2644 | that we cannot do the same with names in OLD_SSA_NAMES because we | |
2645 | want to replace existing instances. */ | |
2646 | if (names_to_release) | |
2647 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) | |
2648 | RESET_BIT (new_ssa_names, i); | |
2649 | ||
84d65814 DN |
2650 | /* First process names in NEW_SSA_NAMES. Otherwise, uses of old |
2651 | names may be considered to be live-in on blocks that contain | |
2652 | definitions for their replacements. */ | |
b6e7e9af | 2653 | EXECUTE_IF_SET_IN_SBITMAP (new_ssa_names, 0, i, sbi) |
95dd3097 | 2654 | prepare_def_site_for (ssa_name (i), insert_phi_p); |
84d65814 | 2655 | |
0bca51f0 DN |
2656 | /* If an old name is in NAMES_TO_RELEASE, we cannot remove it from |
2657 | OLD_SSA_NAMES, but we have to ignore its definition site. */ | |
b6e7e9af | 2658 | EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi) |
84d65814 DN |
2659 | { |
2660 | if (names_to_release == NULL || !bitmap_bit_p (names_to_release, i)) | |
95dd3097 ZD |
2661 | prepare_def_site_for (ssa_name (i), insert_phi_p); |
2662 | prepare_use_sites_for (ssa_name (i), insert_phi_p); | |
b6e7e9af | 2663 | } |
0bca51f0 DN |
2664 | } |
2665 | ||
2666 | ||
2667 | /* Dump all the names replaced by NAME to FILE. */ | |
2668 | ||
2669 | void | |
2670 | dump_names_replaced_by (FILE *file, tree name) | |
2671 | { | |
2672 | unsigned i; | |
2673 | bitmap old_set; | |
2674 | bitmap_iterator bi; | |
2675 | ||
2676 | print_generic_expr (file, name, 0); | |
2677 | fprintf (file, " -> { "); | |
2678 | ||
2679 | old_set = names_replaced_by (name); | |
2680 | EXECUTE_IF_SET_IN_BITMAP (old_set, 0, i, bi) | |
2681 | { | |
2682 | print_generic_expr (file, ssa_name (i), 0); | |
2683 | fprintf (file, " "); | |
2684 | } | |
2685 | ||
2686 | fprintf (file, "}\n"); | |
2687 | } | |
2688 | ||
2689 | ||
2690 | /* Dump all the names replaced by NAME to stderr. */ | |
2691 | ||
24e47c76 | 2692 | DEBUG_FUNCTION void |
0bca51f0 DN |
2693 | debug_names_replaced_by (tree name) |
2694 | { | |
2695 | dump_names_replaced_by (stderr, name); | |
2696 | } | |
2697 | ||
2698 | ||
84d65814 | 2699 | /* Dump SSA update information to FILE. */ |
0bca51f0 DN |
2700 | |
2701 | void | |
84d65814 | 2702 | dump_update_ssa (FILE *file) |
0bca51f0 | 2703 | { |
dfea6c85 | 2704 | unsigned i = 0; |
0bca51f0 DN |
2705 | bitmap_iterator bi; |
2706 | ||
5006671f | 2707 | if (!need_ssa_update_p (cfun)) |
0bca51f0 DN |
2708 | return; |
2709 | ||
2710 | if (new_ssa_names && sbitmap_first_set_bit (new_ssa_names) >= 0) | |
2711 | { | |
b6e7e9af KH |
2712 | sbitmap_iterator sbi; |
2713 | ||
0bca51f0 DN |
2714 | fprintf (file, "\nSSA replacement table\n"); |
2715 | fprintf (file, "N_i -> { O_1 ... O_j } means that N_i replaces " | |
2716 | "O_1, ..., O_j\n\n"); | |
2717 | ||
b6e7e9af KH |
2718 | EXECUTE_IF_SET_IN_SBITMAP (new_ssa_names, 0, i, sbi) |
2719 | dump_names_replaced_by (file, ssa_name (i)); | |
84d65814 DN |
2720 | |
2721 | fprintf (file, "\n"); | |
2722 | fprintf (file, "Number of virtual NEW -> OLD mappings: %7u\n", | |
2723 | update_ssa_stats.num_virtual_mappings); | |
2724 | fprintf (file, "Number of real NEW -> OLD mappings: %7u\n", | |
2725 | update_ssa_stats.num_total_mappings | |
2726 | - update_ssa_stats.num_virtual_mappings); | |
2727 | fprintf (file, "Number of total NEW -> OLD mappings: %7u\n", | |
2728 | update_ssa_stats.num_total_mappings); | |
2729 | ||
2730 | fprintf (file, "\nNumber of virtual symbols: %u\n", | |
2731 | update_ssa_stats.num_virtual_symbols); | |
0bca51f0 DN |
2732 | } |
2733 | ||
5006671f | 2734 | if (!bitmap_empty_p (SYMS_TO_RENAME (cfun))) |
0bca51f0 DN |
2735 | { |
2736 | fprintf (file, "\n\nSymbols to be put in SSA form\n\n"); | |
5006671f RG |
2737 | dump_decl_set (file, SYMS_TO_RENAME (cfun)); |
2738 | fprintf (file, "\n"); | |
0bca51f0 DN |
2739 | } |
2740 | ||
0bca51f0 DN |
2741 | if (names_to_release && !bitmap_empty_p (names_to_release)) |
2742 | { | |
2743 | fprintf (file, "\n\nSSA names to release after updating the SSA web\n\n"); | |
2744 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) | |
2745 | { | |
2746 | print_generic_expr (file, ssa_name (i), 0); | |
2747 | fprintf (file, " "); | |
2748 | } | |
2749 | } | |
2750 | ||
2751 | fprintf (file, "\n\n"); | |
2752 | } | |
2753 | ||
2754 | ||
84d65814 | 2755 | /* Dump SSA update information to stderr. */ |
0bca51f0 | 2756 | |
24e47c76 | 2757 | DEBUG_FUNCTION void |
84d65814 | 2758 | debug_update_ssa (void) |
0bca51f0 | 2759 | { |
84d65814 | 2760 | dump_update_ssa (stderr); |
0bca51f0 DN |
2761 | } |
2762 | ||
2763 | ||
2764 | /* Initialize data structures used for incremental SSA updates. */ | |
2765 | ||
2766 | static void | |
5006671f | 2767 | init_update_ssa (struct function *fn) |
0bca51f0 | 2768 | { |
84d65814 | 2769 | /* Reserve more space than the current number of names. The calls to |
0bca51f0 DN |
2770 | add_new_name_mapping are typically done after creating new SSA |
2771 | names, so we'll need to reallocate these arrays. */ | |
2772 | old_ssa_names = sbitmap_alloc (num_ssa_names + NAME_SETS_GROWTH_FACTOR); | |
2773 | sbitmap_zero (old_ssa_names); | |
2774 | ||
2775 | new_ssa_names = sbitmap_alloc (num_ssa_names + NAME_SETS_GROWTH_FACTOR); | |
2776 | sbitmap_zero (new_ssa_names); | |
2777 | ||
2778 | repl_tbl = htab_create (20, repl_map_hash, repl_map_eq, repl_map_free); | |
0bca51f0 | 2779 | names_to_release = NULL; |
84d65814 DN |
2780 | memset (&update_ssa_stats, 0, sizeof (update_ssa_stats)); |
2781 | update_ssa_stats.virtual_symbols = BITMAP_ALLOC (NULL); | |
5006671f | 2782 | update_ssa_initialized_fn = fn; |
0bca51f0 DN |
2783 | } |
2784 | ||
2785 | ||
2786 | /* Deallocate data structures used for incremental SSA updates. */ | |
2787 | ||
84d65814 | 2788 | void |
0bca51f0 DN |
2789 | delete_update_ssa (void) |
2790 | { | |
2791 | unsigned i; | |
2792 | bitmap_iterator bi; | |
2793 | ||
2794 | sbitmap_free (old_ssa_names); | |
2795 | old_ssa_names = NULL; | |
2796 | ||
2797 | sbitmap_free (new_ssa_names); | |
2798 | new_ssa_names = NULL; | |
2799 | ||
2800 | htab_delete (repl_tbl); | |
2801 | repl_tbl = NULL; | |
2802 | ||
5006671f | 2803 | bitmap_clear (SYMS_TO_RENAME (update_ssa_initialized_fn)); |
84d65814 | 2804 | BITMAP_FREE (update_ssa_stats.virtual_symbols); |
0bca51f0 DN |
2805 | |
2806 | if (names_to_release) | |
2807 | { | |
2808 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) | |
2809 | release_ssa_name (ssa_name (i)); | |
2810 | BITMAP_FREE (names_to_release); | |
2811 | } | |
2812 | ||
95dd3097 | 2813 | clear_ssa_name_info (); |
38635499 DN |
2814 | |
2815 | fini_ssa_renamer (); | |
2816 | ||
2817 | if (blocks_with_phis_to_rewrite) | |
2818 | EXECUTE_IF_SET_IN_BITMAP (blocks_with_phis_to_rewrite, 0, i, bi) | |
2819 | { | |
726a989a | 2820 | gimple_vec phis = VEC_index (gimple_vec, phis_to_rewrite, i); |
38635499 | 2821 | |
726a989a RB |
2822 | VEC_free (gimple, heap, phis); |
2823 | VEC_replace (gimple_vec, phis_to_rewrite, i, NULL); | |
38635499 DN |
2824 | } |
2825 | ||
2826 | BITMAP_FREE (blocks_with_phis_to_rewrite); | |
2827 | BITMAP_FREE (blocks_to_update); | |
5006671f | 2828 | update_ssa_initialized_fn = NULL; |
0bca51f0 DN |
2829 | } |
2830 | ||
2831 | ||
2832 | /* Create a new name for OLD_NAME in statement STMT and replace the | |
2833 | operand pointed to by DEF_P with the newly created name. Return | |
2834 | the new name and register the replacement mapping <NEW, OLD> in | |
2835 | update_ssa's tables. */ | |
2836 | ||
2837 | tree | |
726a989a | 2838 | create_new_def_for (tree old_name, gimple stmt, def_operand_p def) |
0bca51f0 DN |
2839 | { |
2840 | tree new_name = duplicate_ssa_name (old_name, stmt); | |
2841 | ||
2842 | SET_DEF (def, new_name); | |
2843 | ||
726a989a | 2844 | if (gimple_code (stmt) == GIMPLE_PHI) |
0bca51f0 DN |
2845 | { |
2846 | edge e; | |
2847 | edge_iterator ei; | |
726a989a | 2848 | basic_block bb = gimple_bb (stmt); |
0bca51f0 DN |
2849 | |
2850 | /* If needed, mark NEW_NAME as occurring in an abnormal PHI node. */ | |
2851 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2852 | if (e->flags & EDGE_ABNORMAL) | |
2853 | { | |
2854 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_name) = 1; | |
2855 | break; | |
2856 | } | |
2857 | } | |
2858 | ||
2859 | register_new_name_mapping (new_name, old_name); | |
2860 | ||
2861 | /* For the benefit of passes that will be updating the SSA form on | |
2862 | their own, set the current reaching definition of OLD_NAME to be | |
2863 | NEW_NAME. */ | |
2864 | set_current_def (old_name, new_name); | |
2865 | ||
2866 | return new_name; | |
2867 | } | |
2868 | ||
2869 | ||
2870 | /* Register name NEW to be a replacement for name OLD. This function | |
2871 | must be called for every replacement that should be performed by | |
2872 | update_ssa. */ | |
2873 | ||
2874 | void | |
5006671f | 2875 | register_new_name_mapping (tree new_tree, tree old) |
0bca51f0 | 2876 | { |
5006671f RG |
2877 | if (!update_ssa_initialized_fn) |
2878 | init_update_ssa (cfun); | |
2879 | ||
2880 | gcc_assert (update_ssa_initialized_fn == cfun); | |
0bca51f0 | 2881 | |
5006671f | 2882 | add_new_name_mapping (new_tree, old); |
0bca51f0 DN |
2883 | } |
2884 | ||
2885 | ||
2886 | /* Register symbol SYM to be renamed by update_ssa. */ | |
2887 | ||
2888 | void | |
2889 | mark_sym_for_renaming (tree sym) | |
2890 | { | |
5006671f | 2891 | bitmap_set_bit (SYMS_TO_RENAME (cfun), DECL_UID (sym)); |
0bca51f0 DN |
2892 | } |
2893 | ||
2894 | ||
2895 | /* Register all the symbols in SET to be renamed by update_ssa. */ | |
2896 | ||
2897 | void | |
2898 | mark_set_for_renaming (bitmap set) | |
2899 | { | |
2900 | bitmap_iterator bi; | |
2901 | unsigned i; | |
2902 | ||
38635499 | 2903 | if (set == NULL || bitmap_empty_p (set)) |
84d65814 DN |
2904 | return; |
2905 | ||
0bca51f0 | 2906 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) |
38635499 | 2907 | mark_sym_for_renaming (referenced_var (i)); |
0bca51f0 DN |
2908 | } |
2909 | ||
2910 | ||
5006671f RG |
2911 | /* Return true if there is any work to be done by update_ssa |
2912 | for function FN. */ | |
0bca51f0 DN |
2913 | |
2914 | bool | |
5006671f | 2915 | need_ssa_update_p (struct function *fn) |
0bca51f0 | 2916 | { |
5006671f RG |
2917 | gcc_assert (fn != NULL); |
2918 | return (update_ssa_initialized_fn == fn | |
2919 | || (fn->gimple_df | |
2920 | && !bitmap_empty_p (SYMS_TO_RENAME (fn)))); | |
0bca51f0 DN |
2921 | } |
2922 | ||
8f8bb1d2 ZD |
2923 | /* Return true if SSA name mappings have been registered for SSA updating. */ |
2924 | ||
2925 | bool | |
2926 | name_mappings_registered_p (void) | |
2927 | { | |
5006671f RG |
2928 | if (!update_ssa_initialized_fn) |
2929 | return false; | |
2930 | ||
2931 | gcc_assert (update_ssa_initialized_fn == cfun); | |
2932 | ||
8f8bb1d2 ZD |
2933 | return repl_tbl && htab_elements (repl_tbl) > 0; |
2934 | } | |
0bca51f0 DN |
2935 | |
2936 | /* Return true if name N has been registered in the replacement table. */ | |
2937 | ||
2938 | bool | |
726a989a | 2939 | name_registered_for_update_p (tree n ATTRIBUTE_UNUSED) |
0bca51f0 | 2940 | { |
5006671f | 2941 | if (!update_ssa_initialized_fn) |
0bca51f0 DN |
2942 | return false; |
2943 | ||
5006671f RG |
2944 | gcc_assert (update_ssa_initialized_fn == cfun); |
2945 | ||
2946 | return is_new_name (n) || is_old_name (n); | |
0bca51f0 DN |
2947 | } |
2948 | ||
2949 | ||
2950 | /* Return the set of all the SSA names marked to be replaced. */ | |
2951 | ||
2952 | bitmap | |
2953 | ssa_names_to_replace (void) | |
2954 | { | |
dfea6c85 | 2955 | unsigned i = 0; |
0bca51f0 | 2956 | bitmap ret; |
b6e7e9af | 2957 | sbitmap_iterator sbi; |
b8698a0f | 2958 | |
5006671f RG |
2959 | gcc_assert (update_ssa_initialized_fn == NULL |
2960 | || update_ssa_initialized_fn == cfun); | |
2961 | ||
0bca51f0 | 2962 | ret = BITMAP_ALLOC (NULL); |
b6e7e9af KH |
2963 | EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi) |
2964 | bitmap_set_bit (ret, i); | |
0bca51f0 | 2965 | |
0bca51f0 DN |
2966 | return ret; |
2967 | } | |
2968 | ||
2969 | ||
2970 | /* Mark NAME to be released after update_ssa has finished. */ | |
2971 | ||
2972 | void | |
2973 | release_ssa_name_after_update_ssa (tree name) | |
2974 | { | |
5006671f | 2975 | gcc_assert (cfun && update_ssa_initialized_fn == cfun); |
0bca51f0 DN |
2976 | |
2977 | if (names_to_release == NULL) | |
2978 | names_to_release = BITMAP_ALLOC (NULL); | |
2979 | ||
2980 | bitmap_set_bit (names_to_release, SSA_NAME_VERSION (name)); | |
2981 | } | |
2982 | ||
2983 | ||
2984 | /* Insert new PHI nodes to replace VAR. DFS contains dominance | |
2985 | frontier information. BLOCKS is the set of blocks to be updated. | |
2986 | ||
2987 | This is slightly different than the regular PHI insertion | |
2988 | algorithm. The value of UPDATE_FLAGS controls how PHI nodes for | |
2989 | real names (i.e., GIMPLE registers) are inserted: | |
b8698a0f | 2990 | |
0bca51f0 DN |
2991 | - If UPDATE_FLAGS == TODO_update_ssa, we are only interested in PHI |
2992 | nodes inside the region affected by the block that defines VAR | |
2993 | and the blocks that define all its replacements. All these | |
84d65814 | 2994 | definition blocks are stored in DEF_BLOCKS[VAR]->DEF_BLOCKS. |
0bca51f0 DN |
2995 | |
2996 | First, we compute the entry point to the region (ENTRY). This is | |
2997 | given by the nearest common dominator to all the definition | |
2998 | blocks. When computing the iterated dominance frontier (IDF), any | |
2999 | block not strictly dominated by ENTRY is ignored. | |
3000 | ||
3001 | We then call the standard PHI insertion algorithm with the pruned | |
3002 | IDF. | |
3003 | ||
3004 | - If UPDATE_FLAGS == TODO_update_ssa_full_phi, the IDF for real | |
3005 | names is not pruned. PHI nodes are inserted at every IDF block. */ | |
3006 | ||
3007 | static void | |
0fc555fb | 3008 | insert_updated_phi_nodes_for (tree var, bitmap_head *dfs, bitmap blocks, |
0bca51f0 DN |
3009 | unsigned update_flags) |
3010 | { | |
3011 | basic_block entry; | |
3012 | struct def_blocks_d *db; | |
3013 | bitmap idf, pruned_idf; | |
3014 | bitmap_iterator bi; | |
3015 | unsigned i; | |
3016 | ||
3017 | #if defined ENABLE_CHECKING | |
3018 | if (TREE_CODE (var) == SSA_NAME) | |
3019 | gcc_assert (is_old_name (var)); | |
3020 | else | |
3021 | gcc_assert (symbol_marked_for_renaming (var)); | |
3022 | #endif | |
3023 | ||
3024 | /* Get all the definition sites for VAR. */ | |
3025 | db = find_def_blocks_for (var); | |
3026 | ||
3027 | /* No need to do anything if there were no definitions to VAR. */ | |
3028 | if (db == NULL || bitmap_empty_p (db->def_blocks)) | |
3029 | return; | |
3030 | ||
3031 | /* Compute the initial iterated dominance frontier. */ | |
38635499 | 3032 | idf = compute_idf (db->def_blocks, dfs); |
0bca51f0 DN |
3033 | pruned_idf = BITMAP_ALLOC (NULL); |
3034 | ||
3035 | if (TREE_CODE (var) == SSA_NAME) | |
3036 | { | |
3037 | if (update_flags == TODO_update_ssa) | |
3038 | { | |
3039 | /* If doing regular SSA updates for GIMPLE registers, we are | |
3040 | only interested in IDF blocks dominated by the nearest | |
3041 | common dominator of all the definition blocks. */ | |
3042 | entry = nearest_common_dominator_for_set (CDI_DOMINATORS, | |
3043 | db->def_blocks); | |
0bca51f0 DN |
3044 | if (entry != ENTRY_BLOCK_PTR) |
3045 | EXECUTE_IF_SET_IN_BITMAP (idf, 0, i, bi) | |
3046 | if (BASIC_BLOCK (i) != entry | |
3047 | && dominated_by_p (CDI_DOMINATORS, BASIC_BLOCK (i), entry)) | |
3048 | bitmap_set_bit (pruned_idf, i); | |
3049 | } | |
3050 | else | |
3051 | { | |
3052 | /* Otherwise, do not prune the IDF for VAR. */ | |
3053 | gcc_assert (update_flags == TODO_update_ssa_full_phi); | |
3054 | bitmap_copy (pruned_idf, idf); | |
3055 | } | |
3056 | } | |
3057 | else | |
3058 | { | |
3059 | /* Otherwise, VAR is a symbol that needs to be put into SSA form | |
3060 | for the first time, so we need to compute the full IDF for | |
3061 | it. */ | |
3062 | bitmap_copy (pruned_idf, idf); | |
0bca51f0 DN |
3063 | } |
3064 | ||
3065 | if (!bitmap_empty_p (pruned_idf)) | |
3066 | { | |
3067 | /* Make sure that PRUNED_IDF blocks and all their feeding blocks | |
3068 | are included in the region to be updated. The feeding blocks | |
3069 | are important to guarantee that the PHI arguments are renamed | |
3070 | properly. */ | |
38635499 DN |
3071 | |
3072 | /* FIXME, this is not needed if we are updating symbols. We are | |
3073 | already starting at the ENTRY block anyway. */ | |
0bca51f0 DN |
3074 | bitmap_ior_into (blocks, pruned_idf); |
3075 | EXECUTE_IF_SET_IN_BITMAP (pruned_idf, 0, i, bi) | |
3076 | { | |
3077 | edge e; | |
3078 | edge_iterator ei; | |
3079 | basic_block bb = BASIC_BLOCK (i); | |
3080 | ||
3081 | FOR_EACH_EDGE (e, ei, bb->preds) | |
3082 | if (e->src->index >= 0) | |
3083 | bitmap_set_bit (blocks, e->src->index); | |
3084 | } | |
3085 | ||
3086 | insert_phi_nodes_for (var, pruned_idf, true); | |
3087 | } | |
3088 | ||
3089 | BITMAP_FREE (pruned_idf); | |
3090 | BITMAP_FREE (idf); | |
3091 | } | |
3092 | ||
3093 | ||
84d65814 DN |
3094 | /* Heuristic to determine whether SSA name mappings for virtual names |
3095 | should be discarded and their symbols rewritten from scratch. When | |
3096 | there is a large number of mappings for virtual names, the | |
3097 | insertion of PHI nodes for the old names in the mappings takes | |
3098 | considerable more time than if we inserted PHI nodes for the | |
3099 | symbols instead. | |
3100 | ||
3101 | Currently the heuristic takes these stats into account: | |
3102 | ||
3103 | - Number of mappings for virtual SSA names. | |
3104 | - Number of distinct virtual symbols involved in those mappings. | |
3105 | ||
3106 | If the number of virtual mappings is much larger than the number of | |
3107 | virtual symbols, then it will be faster to compute PHI insertion | |
3108 | spots for the symbols. Even if this involves traversing the whole | |
3109 | CFG, which is what happens when symbols are renamed from scratch. */ | |
3110 | ||
3111 | static bool | |
3112 | switch_virtuals_to_full_rewrite_p (void) | |
3113 | { | |
3114 | if (update_ssa_stats.num_virtual_mappings < (unsigned) MIN_VIRTUAL_MAPPINGS) | |
3115 | return false; | |
3116 | ||
3117 | if (update_ssa_stats.num_virtual_mappings | |
3118 | > (unsigned) VIRTUAL_MAPPINGS_TO_SYMS_RATIO | |
3119 | * update_ssa_stats.num_virtual_symbols) | |
3120 | return true; | |
3121 | ||
3122 | return false; | |
3123 | } | |
3124 | ||
3125 | ||
3126 | /* Remove every virtual mapping and mark all the affected virtual | |
3127 | symbols for renaming. */ | |
3128 | ||
3129 | static void | |
3130 | switch_virtuals_to_full_rewrite (void) | |
3131 | { | |
dfea6c85 | 3132 | unsigned i = 0; |
b6e7e9af | 3133 | sbitmap_iterator sbi; |
84d65814 DN |
3134 | |
3135 | if (dump_file) | |
3136 | { | |
3137 | fprintf (dump_file, "\nEnabled virtual name mapping heuristic.\n"); | |
3138 | fprintf (dump_file, "\tNumber of virtual mappings: %7u\n", | |
3139 | update_ssa_stats.num_virtual_mappings); | |
3140 | fprintf (dump_file, "\tNumber of unique virtual symbols: %7u\n", | |
3141 | update_ssa_stats.num_virtual_symbols); | |
3142 | fprintf (dump_file, "Updating FUD-chains from top of CFG will be " | |
3143 | "faster than processing\nthe name mappings.\n\n"); | |
3144 | } | |
3145 | ||
3146 | /* Remove all virtual names from NEW_SSA_NAMES and OLD_SSA_NAMES. | |
3147 | Note that it is not really necessary to remove the mappings from | |
3148 | REPL_TBL, that would only waste time. */ | |
b6e7e9af | 3149 | EXECUTE_IF_SET_IN_SBITMAP (new_ssa_names, 0, i, sbi) |
84d65814 | 3150 | if (!is_gimple_reg (ssa_name (i))) |
b6e7e9af | 3151 | RESET_BIT (new_ssa_names, i); |
84d65814 | 3152 | |
b6e7e9af | 3153 | EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi) |
84d65814 | 3154 | if (!is_gimple_reg (ssa_name (i))) |
b6e7e9af | 3155 | RESET_BIT (old_ssa_names, i); |
84d65814 | 3156 | |
38635499 | 3157 | mark_set_for_renaming (update_ssa_stats.virtual_symbols); |
84d65814 DN |
3158 | } |
3159 | ||
3160 | ||
0bca51f0 DN |
3161 | /* Given a set of newly created SSA names (NEW_SSA_NAMES) and a set of |
3162 | existing SSA names (OLD_SSA_NAMES), update the SSA form so that: | |
3163 | ||
3164 | 1- The names in OLD_SSA_NAMES dominated by the definitions of | |
3165 | NEW_SSA_NAMES are all re-written to be reached by the | |
3166 | appropriate definition from NEW_SSA_NAMES. | |
3167 | ||
3168 | 2- If needed, new PHI nodes are added to the iterated dominance | |
3169 | frontier of the blocks where each of NEW_SSA_NAMES are defined. | |
3170 | ||
3171 | The mapping between OLD_SSA_NAMES and NEW_SSA_NAMES is setup by | |
3172 | calling register_new_name_mapping for every pair of names that the | |
3173 | caller wants to replace. | |
3174 | ||
3175 | The caller identifies the new names that have been inserted and the | |
3176 | names that need to be replaced by calling register_new_name_mapping | |
3177 | for every pair <NEW, OLD>. Note that the function assumes that the | |
3178 | new names have already been inserted in the IL. | |
3179 | ||
3180 | For instance, given the following code: | |
3181 | ||
3182 | 1 L0: | |
3183 | 2 x_1 = PHI (0, x_5) | |
3184 | 3 if (x_1 < 10) | |
3185 | 4 if (x_1 > 7) | |
3186 | 5 y_2 = 0 | |
3187 | 6 else | |
3188 | 7 y_3 = x_1 + x_7 | |
3189 | 8 endif | |
3190 | 9 x_5 = x_1 + 1 | |
3191 | 10 goto L0; | |
3192 | 11 endif | |
3193 | ||
3194 | Suppose that we insert new names x_10 and x_11 (lines 4 and 8). | |
3195 | ||
3196 | 1 L0: | |
3197 | 2 x_1 = PHI (0, x_5) | |
3198 | 3 if (x_1 < 10) | |
3199 | 4 x_10 = ... | |
3200 | 5 if (x_1 > 7) | |
3201 | 6 y_2 = 0 | |
3202 | 7 else | |
3203 | 8 x_11 = ... | |
3204 | 9 y_3 = x_1 + x_7 | |
3205 | 10 endif | |
3206 | 11 x_5 = x_1 + 1 | |
3207 | 12 goto L0; | |
3208 | 13 endif | |
3209 | ||
3210 | We want to replace all the uses of x_1 with the new definitions of | |
3211 | x_10 and x_11. Note that the only uses that should be replaced are | |
3212 | those at lines 5, 9 and 11. Also, the use of x_7 at line 9 should | |
3213 | *not* be replaced (this is why we cannot just mark symbol 'x' for | |
3214 | renaming). | |
3215 | ||
3216 | Additionally, we may need to insert a PHI node at line 11 because | |
3217 | that is a merge point for x_10 and x_11. So the use of x_1 at line | |
3218 | 11 will be replaced with the new PHI node. The insertion of PHI | |
3219 | nodes is optional. They are not strictly necessary to preserve the | |
3220 | SSA form, and depending on what the caller inserted, they may not | |
3221 | even be useful for the optimizers. UPDATE_FLAGS controls various | |
3222 | aspects of how update_ssa operates, see the documentation for | |
3223 | TODO_update_ssa*. */ | |
3224 | ||
3225 | void | |
3226 | update_ssa (unsigned update_flags) | |
3227 | { | |
0bca51f0 DN |
3228 | basic_block bb, start_bb; |
3229 | bitmap_iterator bi; | |
dfea6c85 | 3230 | unsigned i = 0; |
0bca51f0 | 3231 | bool insert_phi_p; |
b6e7e9af | 3232 | sbitmap_iterator sbi; |
0bca51f0 | 3233 | |
5006671f | 3234 | if (!need_ssa_update_p (cfun)) |
0bca51f0 DN |
3235 | return; |
3236 | ||
3237 | timevar_push (TV_TREE_SSA_INCREMENTAL); | |
3238 | ||
5006671f RG |
3239 | if (!update_ssa_initialized_fn) |
3240 | init_update_ssa (cfun); | |
3241 | gcc_assert (update_ssa_initialized_fn == cfun); | |
3242 | ||
2ce79879 ZD |
3243 | blocks_with_phis_to_rewrite = BITMAP_ALLOC (NULL); |
3244 | if (!phis_to_rewrite) | |
726a989a | 3245 | phis_to_rewrite = VEC_alloc (gimple_vec, heap, last_basic_block); |
95dd3097 | 3246 | blocks_to_update = BITMAP_ALLOC (NULL); |
2ce79879 | 3247 | |
0bca51f0 DN |
3248 | /* Ensure that the dominance information is up-to-date. */ |
3249 | calculate_dominance_info (CDI_DOMINATORS); | |
3250 | ||
3251 | /* Only one update flag should be set. */ | |
3252 | gcc_assert (update_flags == TODO_update_ssa | |
3253 | || update_flags == TODO_update_ssa_no_phi | |
3254 | || update_flags == TODO_update_ssa_full_phi | |
3255 | || update_flags == TODO_update_ssa_only_virtuals); | |
3256 | ||
3257 | /* If we only need to update virtuals, remove all the mappings for | |
84d65814 DN |
3258 | real names before proceeding. The caller is responsible for |
3259 | having dealt with the name mappings before calling update_ssa. */ | |
0bca51f0 DN |
3260 | if (update_flags == TODO_update_ssa_only_virtuals) |
3261 | { | |
3262 | sbitmap_zero (old_ssa_names); | |
3263 | sbitmap_zero (new_ssa_names); | |
3264 | htab_empty (repl_tbl); | |
0bca51f0 DN |
3265 | } |
3266 | ||
84d65814 | 3267 | insert_phi_p = (update_flags != TODO_update_ssa_no_phi); |
0bca51f0 DN |
3268 | |
3269 | if (insert_phi_p) | |
3270 | { | |
9caf90a8 KH |
3271 | /* If the caller requested PHI nodes to be added, initialize |
3272 | live-in information data structures (DEF_BLOCKS). */ | |
0bca51f0 DN |
3273 | |
3274 | /* For each SSA name N, the DEF_BLOCKS table describes where the | |
3275 | name is defined, which blocks have PHI nodes for N, and which | |
3276 | blocks have uses of N (i.e., N is live-on-entry in those | |
3277 | blocks). */ | |
3278 | def_blocks = htab_create (num_ssa_names, def_blocks_hash, | |
3279 | def_blocks_eq, def_blocks_free); | |
3280 | } | |
3281 | else | |
3282 | { | |
0bca51f0 DN |
3283 | def_blocks = NULL; |
3284 | } | |
3285 | ||
84d65814 DN |
3286 | /* Heuristic to avoid massive slow downs when the replacement |
3287 | mappings include lots of virtual names. */ | |
3288 | if (insert_phi_p && switch_virtuals_to_full_rewrite_p ()) | |
3289 | switch_virtuals_to_full_rewrite (); | |
3290 | ||
3291 | /* If there are names defined in the replacement table, prepare | |
3292 | definition and use sites for all the names in NEW_SSA_NAMES and | |
3293 | OLD_SSA_NAMES. */ | |
3294 | if (sbitmap_first_set_bit (new_ssa_names) >= 0) | |
3295 | { | |
95dd3097 | 3296 | prepare_names_to_update (insert_phi_p); |
84d65814 DN |
3297 | |
3298 | /* If all the names in NEW_SSA_NAMES had been marked for | |
3299 | removal, and there are no symbols to rename, then there's | |
3300 | nothing else to do. */ | |
3301 | if (sbitmap_first_set_bit (new_ssa_names) < 0 | |
5006671f | 3302 | && bitmap_empty_p (SYMS_TO_RENAME (cfun))) |
84d65814 DN |
3303 | goto done; |
3304 | } | |
3305 | ||
3306 | /* Next, determine the block at which to start the renaming process. */ | |
5006671f | 3307 | if (!bitmap_empty_p (SYMS_TO_RENAME (cfun))) |
84d65814 DN |
3308 | { |
3309 | /* If we have to rename some symbols from scratch, we need to | |
3310 | start the process at the root of the CFG. FIXME, it should | |
3311 | be possible to determine the nearest block that had a | |
3312 | definition for each of the symbols that are marked for | |
3313 | updating. For now this seems more work than it's worth. */ | |
3314 | start_bb = ENTRY_BLOCK_PTR; | |
3315 | ||
38635499 DN |
3316 | /* Traverse the CFG looking for existing definitions and uses of |
3317 | symbols in SYMS_TO_RENAME. Mark interesting blocks and | |
3318 | statements and set local live-in information for the PHI | |
3319 | placement heuristics. */ | |
95dd3097 | 3320 | prepare_block_for_update (start_bb, insert_phi_p); |
0bca51f0 DN |
3321 | } |
3322 | else | |
84d65814 DN |
3323 | { |
3324 | /* Otherwise, the entry block to the region is the nearest | |
3325 | common dominator for the blocks in BLOCKS. */ | |
95dd3097 ZD |
3326 | start_bb = nearest_common_dominator_for_set (CDI_DOMINATORS, |
3327 | blocks_to_update); | |
84d65814 | 3328 | } |
0bca51f0 DN |
3329 | |
3330 | /* If requested, insert PHI nodes at the iterated dominance frontier | |
84d65814 | 3331 | of every block, creating new definitions for names in OLD_SSA_NAMES |
0bca51f0 DN |
3332 | and for symbols in SYMS_TO_RENAME. */ |
3333 | if (insert_phi_p) | |
3334 | { | |
0fc555fb | 3335 | bitmap_head *dfs; |
9caf90a8 KH |
3336 | |
3337 | /* If the caller requested PHI nodes to be added, compute | |
3338 | dominance frontiers. */ | |
0fc555fb | 3339 | dfs = XNEWVEC (bitmap_head, last_basic_block); |
9caf90a8 | 3340 | FOR_EACH_BB (bb) |
0fc555fb | 3341 | bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack); |
9caf90a8 KH |
3342 | compute_dominance_frontiers (dfs); |
3343 | ||
0bca51f0 DN |
3344 | if (sbitmap_first_set_bit (old_ssa_names) >= 0) |
3345 | { | |
b6e7e9af KH |
3346 | sbitmap_iterator sbi; |
3347 | ||
84d65814 DN |
3348 | /* insert_update_phi_nodes_for will call add_new_name_mapping |
3349 | when inserting new PHI nodes, so the set OLD_SSA_NAMES | |
3350 | will grow while we are traversing it (but it will not | |
3351 | gain any new members). Copy OLD_SSA_NAMES to a temporary | |
3352 | for traversal. */ | |
0bca51f0 DN |
3353 | sbitmap tmp = sbitmap_alloc (old_ssa_names->n_bits); |
3354 | sbitmap_copy (tmp, old_ssa_names); | |
b6e7e9af | 3355 | EXECUTE_IF_SET_IN_SBITMAP (tmp, 0, i, sbi) |
95dd3097 | 3356 | insert_updated_phi_nodes_for (ssa_name (i), dfs, blocks_to_update, |
b6e7e9af | 3357 | update_flags); |
0bca51f0 DN |
3358 | sbitmap_free (tmp); |
3359 | } | |
3360 | ||
5006671f | 3361 | EXECUTE_IF_SET_IN_BITMAP (SYMS_TO_RENAME (cfun), 0, i, bi) |
38635499 DN |
3362 | insert_updated_phi_nodes_for (referenced_var (i), dfs, blocks_to_update, |
3363 | update_flags); | |
0bca51f0 | 3364 | |
9caf90a8 | 3365 | FOR_EACH_BB (bb) |
0fc555fb | 3366 | bitmap_clear (&dfs[bb->index]); |
9caf90a8 KH |
3367 | free (dfs); |
3368 | ||
0bca51f0 DN |
3369 | /* Insertion of PHI nodes may have added blocks to the region. |
3370 | We need to re-compute START_BB to include the newly added | |
3371 | blocks. */ | |
3372 | if (start_bb != ENTRY_BLOCK_PTR) | |
95dd3097 ZD |
3373 | start_bb = nearest_common_dominator_for_set (CDI_DOMINATORS, |
3374 | blocks_to_update); | |
0bca51f0 DN |
3375 | } |
3376 | ||
3377 | /* Reset the current definition for name and symbol before renaming | |
3378 | the sub-graph. */ | |
b6e7e9af KH |
3379 | EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi) |
3380 | set_current_def (ssa_name (i), NULL_TREE); | |
0bca51f0 | 3381 | |
5006671f | 3382 | EXECUTE_IF_SET_IN_BITMAP (SYMS_TO_RENAME (cfun), 0, i, bi) |
0bca51f0 DN |
3383 | set_current_def (referenced_var (i), NULL_TREE); |
3384 | ||
3385 | /* Now start the renaming process at START_BB. */ | |
ccf5c864 PB |
3386 | interesting_blocks = sbitmap_alloc (last_basic_block); |
3387 | sbitmap_zero (interesting_blocks); | |
95dd3097 | 3388 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
ccf5c864 | 3389 | SET_BIT (interesting_blocks, i); |
0bca51f0 | 3390 | |
ccf5c864 | 3391 | rewrite_blocks (start_bb, REWRITE_UPDATE); |
0bca51f0 | 3392 | |
ccf5c864 | 3393 | sbitmap_free (interesting_blocks); |
0bca51f0 DN |
3394 | |
3395 | /* Debugging dumps. */ | |
3396 | if (dump_file) | |
3397 | { | |
3398 | int c; | |
3399 | unsigned i; | |
3400 | ||
84d65814 | 3401 | dump_update_ssa (dump_file); |
0bca51f0 DN |
3402 | |
3403 | fprintf (dump_file, "Incremental SSA update started at block: %d\n\n", | |
3404 | start_bb->index); | |
3405 | ||
3406 | c = 0; | |
95dd3097 | 3407 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
0bca51f0 DN |
3408 | c++; |
3409 | fprintf (dump_file, "Number of blocks in CFG: %d\n", last_basic_block); | |
3410 | fprintf (dump_file, "Number of blocks to update: %d (%3.0f%%)\n\n", | |
3411 | c, PERCENT (c, last_basic_block)); | |
3412 | ||
3413 | if (dump_flags & TDF_DETAILS) | |
3414 | { | |
3415 | fprintf (dump_file, "Affected blocks: "); | |
95dd3097 | 3416 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
0bca51f0 DN |
3417 | fprintf (dump_file, "%u ", i); |
3418 | fprintf (dump_file, "\n"); | |
3419 | } | |
3420 | ||
3421 | fprintf (dump_file, "\n\n"); | |
3422 | } | |
3423 | ||
3424 | /* Free allocated memory. */ | |
84d65814 | 3425 | done: |
0bca51f0 DN |
3426 | delete_update_ssa (); |
3427 | ||
3428 | timevar_pop (TV_TREE_SSA_INCREMENTAL); | |
3429 | } |