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6de9cd9a | 1 | /* Rewrite a program in Normal form into SSA. |
d1e082c2 | 2 | Copyright (C) 2001-2013 Free Software Foundation, Inc. |
6de9cd9a DN |
3 | Contributed by Diego Novillo <dnovillo@redhat.com> |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9dcd6f09 | 9 | the Free Software Foundation; either version 3, or (at your option) |
6de9cd9a DN |
10 | any later version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
6de9cd9a DN |
20 | |
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
25 | #include "tree.h" | |
26 | #include "flags.h" | |
6de9cd9a DN |
27 | #include "tm_p.h" |
28 | #include "langhooks.h" | |
6de9cd9a | 29 | #include "basic-block.h" |
6de9cd9a | 30 | #include "function.h" |
cf835838 | 31 | #include "gimple-pretty-print.h" |
6de9cd9a | 32 | #include "bitmap.h" |
7a300452 | 33 | #include "tree-ssa.h" |
726a989a | 34 | #include "gimple.h" |
6de9cd9a | 35 | #include "tree-inline.h" |
bf190e8d | 36 | #include "hash-table.h" |
6de9cd9a DN |
37 | #include "tree-pass.h" |
38 | #include "cfgloop.h" | |
39 | #include "domwalk.h" | |
84d65814 | 40 | #include "params.h" |
d8d707b4 | 41 | #include "diagnostic-core.h" |
6de9cd9a | 42 | |
726a989a | 43 | |
6de9cd9a DN |
44 | /* This file builds the SSA form for a function as described in: |
45 | R. Cytron, J. Ferrante, B. Rosen, M. Wegman, and K. Zadeck. Efficiently | |
46 | Computing Static Single Assignment Form and the Control Dependence | |
47 | Graph. ACM Transactions on Programming Languages and Systems, | |
48 | 13(4):451-490, October 1991. */ | |
49 | ||
6de9cd9a DN |
50 | /* Structure to map a variable VAR to the set of blocks that contain |
51 | definitions for VAR. */ | |
52 | struct def_blocks_d | |
53 | { | |
6de9cd9a DN |
54 | /* Blocks that contain definitions of VAR. Bit I will be set if the |
55 | Ith block contains a definition of VAR. */ | |
56 | bitmap def_blocks; | |
57 | ||
7256233c | 58 | /* Blocks that contain a PHI node for VAR. */ |
5f240ec4 ZD |
59 | bitmap phi_blocks; |
60 | ||
6de9cd9a DN |
61 | /* Blocks where VAR is live-on-entry. Similar semantics as |
62 | DEF_BLOCKS. */ | |
63 | bitmap livein_blocks; | |
64 | }; | |
65 | ||
d9ed2fbd RG |
66 | typedef struct def_blocks_d *def_blocks_p; |
67 | ||
6de9cd9a | 68 | |
9fae925b | 69 | /* Stack of trees used to restore the global currdefs to its original |
0bca51f0 DN |
70 | state after completing rewriting of a block and its dominator |
71 | children. Its elements have the following properties: | |
9fae925b | 72 | |
38635499 DN |
73 | - An SSA_NAME (N) indicates that the current definition of the |
74 | underlying variable should be set to the given SSA_NAME. If the | |
75 | symbol associated with the SSA_NAME is not a GIMPLE register, the | |
76 | next slot in the stack must be a _DECL node (SYM). In this case, | |
77 | the name N in the previous slot is the current reaching | |
78 | definition for SYM. | |
9fae925b | 79 | |
0bca51f0 DN |
80 | - A _DECL node indicates that the underlying variable has no |
81 | current definition. | |
7256233c | 82 | |
38635499 | 83 | - A NULL node at the top entry is used to mark the last slot |
0bca51f0 | 84 | associated with the current block. */ |
9771b263 | 85 | static vec<tree> block_defs_stack; |
3a2e4b46 | 86 | |
726a989a | 87 | |
0bca51f0 DN |
88 | /* Set of existing SSA names being replaced by update_ssa. */ |
89 | static sbitmap old_ssa_names; | |
90 | ||
91 | /* Set of new SSA names being added by update_ssa. Note that both | |
92 | NEW_SSA_NAMES and OLD_SSA_NAMES are dense bitmaps because most of | |
93 | the operations done on them are presence tests. */ | |
94 | static sbitmap new_ssa_names; | |
95 | ||
16876bdc | 96 | static sbitmap interesting_blocks; |
726a989a | 97 | |
0bca51f0 DN |
98 | /* Set of SSA names that have been marked to be released after they |
99 | were registered in the replacement table. They will be finally | |
100 | released after we finish updating the SSA web. */ | |
101 | static bitmap names_to_release; | |
102 | ||
9771b263 | 103 | /* vec of vec of PHIs to rewrite in a basic block. Element I corresponds |
580b2c2e SB |
104 | the to basic block with index I. Allocated once per compilation, *not* |
105 | released between different functions. */ | |
9771b263 | 106 | static vec<gimple_vec> phis_to_rewrite; |
2ce79879 ZD |
107 | |
108 | /* The bitmap of non-NULL elements of PHIS_TO_REWRITE. */ | |
2ce79879 ZD |
109 | static bitmap blocks_with_phis_to_rewrite; |
110 | ||
0bca51f0 | 111 | /* Growth factor for NEW_SSA_NAMES and OLD_SSA_NAMES. These sets need |
45db3141 RG |
112 | to grow as the callers to create_new_def_for will create new names on |
113 | the fly. | |
114 | FIXME. Currently set to 1/3 to avoid frequent reallocations but still | |
115 | need to find a reasonable growth strategy. */ | |
0bca51f0 DN |
116 | #define NAME_SETS_GROWTH_FACTOR (MAX (3, num_ssa_names / 3)) |
117 | ||
0bca51f0 | 118 | |
5006671f | 119 | /* The function the SSA updating data structures have been initialized for. |
45db3141 | 120 | NULL if they need to be initialized by create_new_def_for. */ |
5006671f | 121 | static struct function *update_ssa_initialized_fn = NULL; |
0bca51f0 | 122 | |
6de9cd9a DN |
123 | /* Global data to attach to the main dominator walk structure. */ |
124 | struct mark_def_sites_global_data | |
125 | { | |
0bca51f0 DN |
126 | /* This bitmap contains the variables which are set before they |
127 | are used in a basic block. */ | |
7d793e36 | 128 | bitmap kills; |
6de9cd9a DN |
129 | }; |
130 | ||
8812aab1 RG |
131 | /* Information stored for both SSA names and decls. */ |
132 | struct common_info_d | |
b4e209fd | 133 | { |
b4e209fd RG |
134 | /* This field indicates whether or not the variable may need PHI nodes. |
135 | See the enum's definition for more detailed information about the | |
136 | states. */ | |
137 | ENUM_BITFIELD (need_phi_state) need_phi_state : 2; | |
138 | ||
8812aab1 | 139 | /* The current reaching definition replacing this var. */ |
b4e209fd RG |
140 | tree current_def; |
141 | ||
8812aab1 | 142 | /* Definitions for this var. */ |
b4e209fd RG |
143 | struct def_blocks_d def_blocks; |
144 | }; | |
145 | ||
8812aab1 RG |
146 | /* The information associated with decls and SSA names. */ |
147 | typedef struct common_info_d *common_info_p; | |
148 | ||
149 | /* Information stored for decls. */ | |
150 | struct var_info_d | |
151 | { | |
152 | /* The variable. */ | |
153 | tree var; | |
154 | ||
155 | /* Information stored for both SSA names and decls. */ | |
156 | struct common_info_d info; | |
157 | }; | |
158 | ||
b4e209fd RG |
159 | /* The information associated with decls. */ |
160 | typedef struct var_info_d *var_info_p; | |
161 | ||
b4e209fd | 162 | |
bf190e8d LC |
163 | /* VAR_INFOS hashtable helpers. */ |
164 | ||
165 | struct var_info_hasher : typed_free_remove <var_info_d> | |
166 | { | |
167 | typedef var_info_d value_type; | |
168 | typedef var_info_d compare_type; | |
169 | static inline hashval_t hash (const value_type *); | |
170 | static inline bool equal (const value_type *, const compare_type *); | |
171 | }; | |
172 | ||
173 | inline hashval_t | |
174 | var_info_hasher::hash (const value_type *p) | |
175 | { | |
176 | return DECL_UID (p->var); | |
177 | } | |
178 | ||
179 | inline bool | |
180 | var_info_hasher::equal (const value_type *p1, const compare_type *p2) | |
181 | { | |
182 | return p1->var == p2->var; | |
183 | } | |
184 | ||
185 | ||
b4e209fd RG |
186 | /* Each entry in VAR_INFOS contains an element of type STRUCT |
187 | VAR_INFO_D. */ | |
bf190e8d | 188 | static hash_table <var_info_hasher> var_infos; |
b4e209fd RG |
189 | |
190 | ||
0bca51f0 | 191 | /* Information stored for SSA names. */ |
5f240ec4 ZD |
192 | struct ssa_name_info |
193 | { | |
891f2df6 RG |
194 | /* Age of this record (so that info_for_ssa_name table can be cleared |
195 | quickly); if AGE < CURRENT_INFO_FOR_SSA_NAME_AGE, then the fields | |
196 | are assumed to be null. */ | |
197 | unsigned age; | |
95dd3097 | 198 | |
891f2df6 RG |
199 | /* Replacement mappings, allocated from update_ssa_obstack. */ |
200 | bitmap repl_set; | |
b4e209fd | 201 | |
8812aab1 RG |
202 | /* Information stored for both SSA names and decls. */ |
203 | struct common_info_d info; | |
5f240ec4 | 204 | }; |
6de9cd9a | 205 | |
95dd3097 ZD |
206 | /* The information associated with names. */ |
207 | typedef struct ssa_name_info *ssa_name_info_p; | |
95dd3097 | 208 | |
9771b263 | 209 | static vec<ssa_name_info_p> info_for_ssa_name; |
95dd3097 ZD |
210 | static unsigned current_info_for_ssa_name_age; |
211 | ||
891f2df6 RG |
212 | static bitmap_obstack update_ssa_obstack; |
213 | ||
95dd3097 | 214 | /* The set of blocks affected by update_ssa. */ |
95dd3097 | 215 | static bitmap blocks_to_update; |
6de9cd9a | 216 | |
0bca51f0 DN |
217 | /* The main entry point to the SSA renamer (rewrite_blocks) may be |
218 | called several times to do different, but related, tasks. | |
219 | Initially, we need it to rename the whole program into SSA form. | |
220 | At other times, we may need it to only rename into SSA newly | |
221 | exposed symbols. Finally, we can also call it to incrementally fix | |
222 | an already built SSA web. */ | |
223 | enum rewrite_mode { | |
224 | /* Convert the whole function into SSA form. */ | |
225 | REWRITE_ALL, | |
226 | ||
227 | /* Incrementally update the SSA web by replacing existing SSA | |
228 | names with new ones. See update_ssa for details. */ | |
229 | REWRITE_UPDATE | |
230 | }; | |
231 | ||
232 | ||
0bca51f0 | 233 | |
7d5f9cc6 | 234 | |
84d65814 DN |
235 | /* Prototypes for debugging functions. */ |
236 | extern void dump_tree_ssa (FILE *); | |
237 | extern void debug_tree_ssa (void); | |
238 | extern void debug_def_blocks (void); | |
239 | extern void dump_tree_ssa_stats (FILE *); | |
240 | extern void debug_tree_ssa_stats (void); | |
38635499 DN |
241 | extern void dump_update_ssa (FILE *); |
242 | extern void debug_update_ssa (void); | |
243 | extern void dump_names_replaced_by (FILE *, tree); | |
244 | extern void debug_names_replaced_by (tree); | |
b4e209fd RG |
245 | extern void dump_var_infos (FILE *); |
246 | extern void debug_var_infos (void); | |
38635499 DN |
247 | extern void dump_defs_stack (FILE *, int); |
248 | extern void debug_defs_stack (int); | |
249 | extern void dump_currdefs (FILE *); | |
250 | extern void debug_currdefs (void); | |
84d65814 | 251 | |
13714310 RG |
252 | |
253 | /* The set of symbols we ought to re-write into SSA form in update_ssa. */ | |
254 | static bitmap symbols_to_rename_set; | |
9771b263 | 255 | static vec<tree> symbols_to_rename; |
13714310 RG |
256 | |
257 | /* Mark SYM for renaming. */ | |
258 | ||
259 | static void | |
260 | mark_for_renaming (tree sym) | |
261 | { | |
262 | if (!symbols_to_rename_set) | |
263 | symbols_to_rename_set = BITMAP_ALLOC (NULL); | |
264 | if (bitmap_set_bit (symbols_to_rename_set, DECL_UID (sym))) | |
9771b263 | 265 | symbols_to_rename.safe_push (sym); |
13714310 RG |
266 | } |
267 | ||
268 | /* Return true if SYM is marked for renaming. */ | |
269 | ||
270 | static bool | |
271 | marked_for_renaming (tree sym) | |
272 | { | |
70b5e7dc | 273 | if (!symbols_to_rename_set || sym == NULL_TREE) |
13714310 RG |
274 | return false; |
275 | return bitmap_bit_p (symbols_to_rename_set, DECL_UID (sym)); | |
276 | } | |
277 | ||
278 | ||
726a989a RB |
279 | /* Return true if STMT needs to be rewritten. When renaming a subset |
280 | of the variables, not all statements will be processed. This is | |
281 | decided in mark_def_sites. */ | |
282 | ||
283 | static inline bool | |
284 | rewrite_uses_p (gimple stmt) | |
285 | { | |
286 | return gimple_visited_p (stmt); | |
287 | } | |
288 | ||
289 | ||
290 | /* Set the rewrite marker on STMT to the value given by REWRITE_P. */ | |
291 | ||
292 | static inline void | |
293 | set_rewrite_uses (gimple stmt, bool rewrite_p) | |
294 | { | |
295 | gimple_set_visited (stmt, rewrite_p); | |
296 | } | |
297 | ||
298 | ||
299 | /* Return true if the DEFs created by statement STMT should be | |
300 | registered when marking new definition sites. This is slightly | |
301 | different than rewrite_uses_p: it's used by update_ssa to | |
302 | distinguish statements that need to have both uses and defs | |
303 | processed from those that only need to have their defs processed. | |
304 | Statements that define new SSA names only need to have their defs | |
305 | registered, but they don't need to have their uses renamed. */ | |
306 | ||
307 | static inline bool | |
308 | register_defs_p (gimple stmt) | |
309 | { | |
310 | return gimple_plf (stmt, GF_PLF_1) != 0; | |
311 | } | |
312 | ||
313 | ||
314 | /* If REGISTER_DEFS_P is true, mark STMT to have its DEFs registered. */ | |
315 | ||
316 | static inline void | |
317 | set_register_defs (gimple stmt, bool register_defs_p) | |
318 | { | |
319 | gimple_set_plf (stmt, GF_PLF_1, register_defs_p); | |
320 | } | |
321 | ||
322 | ||
5f240ec4 ZD |
323 | /* Get the information associated with NAME. */ |
324 | ||
38635499 | 325 | static inline ssa_name_info_p |
5f240ec4 ZD |
326 | get_ssa_name_ann (tree name) |
327 | { | |
95dd3097 | 328 | unsigned ver = SSA_NAME_VERSION (name); |
9771b263 | 329 | unsigned len = info_for_ssa_name.length (); |
95dd3097 ZD |
330 | struct ssa_name_info *info; |
331 | ||
f5843d08 | 332 | /* Re-allocate the vector at most once per update/into-SSA. */ |
95dd3097 | 333 | if (ver >= len) |
9771b263 | 334 | info_for_ssa_name.safe_grow_cleared (num_ssa_names); |
f5843d08 RG |
335 | |
336 | /* But allocate infos lazily. */ | |
9771b263 | 337 | info = info_for_ssa_name[ver]; |
f5843d08 | 338 | if (!info) |
95dd3097 | 339 | { |
f5843d08 RG |
340 | info = XCNEW (struct ssa_name_info); |
341 | info->age = current_info_for_ssa_name_age; | |
342 | info->info.need_phi_state = NEED_PHI_STATE_UNKNOWN; | |
9771b263 | 343 | info_for_ssa_name[ver] = info; |
95dd3097 ZD |
344 | } |
345 | ||
95dd3097 ZD |
346 | if (info->age < current_info_for_ssa_name_age) |
347 | { | |
95dd3097 | 348 | info->age = current_info_for_ssa_name_age; |
8812aab1 RG |
349 | info->repl_set = NULL; |
350 | info->info.need_phi_state = NEED_PHI_STATE_UNKNOWN; | |
351 | info->info.current_def = NULL_TREE; | |
352 | info->info.def_blocks.def_blocks = NULL; | |
353 | info->info.def_blocks.phi_blocks = NULL; | |
354 | info->info.def_blocks.livein_blocks = NULL; | |
95dd3097 | 355 | } |
5f240ec4 | 356 | |
95dd3097 | 357 | return info; |
5f240ec4 ZD |
358 | } |
359 | ||
b4e209fd RG |
360 | /* Return and allocate the auxiliar information for DECL. */ |
361 | ||
362 | static inline var_info_p | |
363 | get_var_info (tree decl) | |
364 | { | |
365 | struct var_info_d vi; | |
bf190e8d | 366 | var_info_d **slot; |
b4e209fd | 367 | vi.var = decl; |
bf190e8d | 368 | slot = var_infos.find_slot_with_hash (&vi, DECL_UID (decl), INSERT); |
b4e209fd RG |
369 | if (*slot == NULL) |
370 | { | |
371 | var_info_p v = XCNEW (struct var_info_d); | |
372 | v->var = decl; | |
bf190e8d | 373 | *slot = v; |
b4e209fd RG |
374 | return v; |
375 | } | |
bf190e8d | 376 | return *slot; |
b4e209fd RG |
377 | } |
378 | ||
38635499 DN |
379 | |
380 | /* Clears info for SSA names. */ | |
95dd3097 ZD |
381 | |
382 | static void | |
383 | clear_ssa_name_info (void) | |
384 | { | |
385 | current_info_for_ssa_name_age++; | |
891f2df6 RG |
386 | |
387 | /* If current_info_for_ssa_name_age wraps we use stale information. | |
388 | Asser that this does not happen. */ | |
389 | gcc_assert (current_info_for_ssa_name_age != 0); | |
95dd3097 | 390 | } |
7256233c | 391 | |
38635499 | 392 | |
8812aab1 | 393 | /* Get access to the auxiliar information stored per SSA name or decl. */ |
5f240ec4 | 394 | |
8812aab1 RG |
395 | static inline common_info_p |
396 | get_common_info (tree var) | |
5f240ec4 ZD |
397 | { |
398 | if (TREE_CODE (var) == SSA_NAME) | |
8812aab1 | 399 | return &get_ssa_name_ann (var)->info; |
5f240ec4 | 400 | else |
8812aab1 | 401 | return &get_var_info (var)->info; |
5f240ec4 ZD |
402 | } |
403 | ||
7256233c | 404 | |
5f240ec4 ZD |
405 | /* Return the current definition for VAR. */ |
406 | ||
84d65814 | 407 | tree |
5f240ec4 ZD |
408 | get_current_def (tree var) |
409 | { | |
8812aab1 | 410 | return get_common_info (var)->current_def; |
5f240ec4 ZD |
411 | } |
412 | ||
7256233c | 413 | |
5f240ec4 ZD |
414 | /* Sets current definition of VAR to DEF. */ |
415 | ||
84d65814 | 416 | void |
5f240ec4 ZD |
417 | set_current_def (tree var, tree def) |
418 | { | |
8812aab1 | 419 | get_common_info (var)->current_def = def; |
5f240ec4 ZD |
420 | } |
421 | ||
95dd3097 ZD |
422 | /* Cleans up the REWRITE_THIS_STMT and REGISTER_DEFS_IN_THIS_STMT flags for |
423 | all statements in basic block BB. */ | |
424 | ||
425 | static void | |
426 | initialize_flags_in_bb (basic_block bb) | |
427 | { | |
726a989a RB |
428 | gimple stmt; |
429 | gimple_stmt_iterator gsi; | |
95dd3097 | 430 | |
726a989a | 431 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
95dd3097 | 432 | { |
726a989a RB |
433 | gimple phi = gsi_stmt (gsi); |
434 | set_rewrite_uses (phi, false); | |
435 | set_register_defs (phi, false); | |
95dd3097 ZD |
436 | } |
437 | ||
726a989a | 438 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
95dd3097 | 439 | { |
726a989a RB |
440 | stmt = gsi_stmt (gsi); |
441 | ||
95dd3097 ZD |
442 | /* We are going to use the operand cache API, such as |
443 | SET_USE, SET_DEF, and FOR_EACH_IMM_USE_FAST. The operand | |
444 | cache for each statement should be up-to-date. */ | |
4ad14919 | 445 | gcc_checking_assert (!gimple_modified_p (stmt)); |
726a989a RB |
446 | set_rewrite_uses (stmt, false); |
447 | set_register_defs (stmt, false); | |
95dd3097 ZD |
448 | } |
449 | } | |
450 | ||
451 | /* Mark block BB as interesting for update_ssa. */ | |
452 | ||
453 | static void | |
454 | mark_block_for_update (basic_block bb) | |
455 | { | |
4ad14919 | 456 | gcc_checking_assert (blocks_to_update != NULL); |
f3cf730b | 457 | if (!bitmap_set_bit (blocks_to_update, bb->index)) |
95dd3097 | 458 | return; |
95dd3097 ZD |
459 | initialize_flags_in_bb (bb); |
460 | } | |
461 | ||
7256233c DN |
462 | /* Return the set of blocks where variable VAR is defined and the blocks |
463 | where VAR is live on entry (livein). If no entry is found in | |
464 | DEF_BLOCKS, a new one is created and returned. */ | |
6de9cd9a | 465 | |
7256233c | 466 | static inline struct def_blocks_d * |
8812aab1 | 467 | get_def_blocks_for (common_info_p info) |
6de9cd9a | 468 | { |
8812aab1 | 469 | struct def_blocks_d *db_p = &info->def_blocks; |
b4e209fd | 470 | if (!db_p->def_blocks) |
6de9cd9a | 471 | { |
b4e209fd RG |
472 | db_p->def_blocks = BITMAP_ALLOC (&update_ssa_obstack); |
473 | db_p->phi_blocks = BITMAP_ALLOC (&update_ssa_obstack); | |
474 | db_p->livein_blocks = BITMAP_ALLOC (&update_ssa_obstack); | |
a32b97a2 BB |
475 | } |
476 | ||
7256233c | 477 | return db_p; |
6de9cd9a DN |
478 | } |
479 | ||
7d5f9cc6 | 480 | |
5f240ec4 | 481 | /* Mark block BB as the definition site for variable VAR. PHI_P is true if |
0bca51f0 | 482 | VAR is defined by a PHI node. */ |
6de9cd9a DN |
483 | |
484 | static void | |
0bca51f0 | 485 | set_def_block (tree var, basic_block bb, bool phi_p) |
6de9cd9a DN |
486 | { |
487 | struct def_blocks_d *db_p; | |
8812aab1 | 488 | common_info_p info; |
34eb8991 | 489 | |
8812aab1 RG |
490 | info = get_common_info (var); |
491 | db_p = get_def_blocks_for (info); | |
6de9cd9a DN |
492 | |
493 | /* Set the bit corresponding to the block where VAR is defined. */ | |
494 | bitmap_set_bit (db_p->def_blocks, bb->index); | |
5f240ec4 ZD |
495 | if (phi_p) |
496 | bitmap_set_bit (db_p->phi_blocks, bb->index); | |
6de9cd9a | 497 | |
7256233c | 498 | /* Keep track of whether or not we may need to insert PHI nodes. |
6de9cd9a DN |
499 | |
500 | If we are in the UNKNOWN state, then this is the first definition | |
501 | of VAR. Additionally, we have not seen any uses of VAR yet, so | |
7256233c | 502 | we do not need a PHI node for this variable at this time (i.e., |
6de9cd9a DN |
503 | transition to NEED_PHI_STATE_NO). |
504 | ||
505 | If we are in any other state, then we either have multiple definitions | |
506 | of this variable occurring in different blocks or we saw a use of the | |
507 | variable which was not dominated by the block containing the | |
508 | definition(s). In this case we may need a PHI node, so enter | |
509 | state NEED_PHI_STATE_MAYBE. */ | |
8812aab1 RG |
510 | if (info->need_phi_state == NEED_PHI_STATE_UNKNOWN) |
511 | info->need_phi_state = NEED_PHI_STATE_NO; | |
6de9cd9a | 512 | else |
8812aab1 | 513 | info->need_phi_state = NEED_PHI_STATE_MAYBE; |
6de9cd9a DN |
514 | } |
515 | ||
516 | ||
517 | /* Mark block BB as having VAR live at the entry to BB. */ | |
518 | ||
519 | static void | |
520 | set_livein_block (tree var, basic_block bb) | |
521 | { | |
8812aab1 | 522 | common_info_p info; |
6de9cd9a | 523 | struct def_blocks_d *db_p; |
6de9cd9a | 524 | |
8812aab1 RG |
525 | info = get_common_info (var); |
526 | db_p = get_def_blocks_for (info); | |
6de9cd9a DN |
527 | |
528 | /* Set the bit corresponding to the block where VAR is live in. */ | |
529 | bitmap_set_bit (db_p->livein_blocks, bb->index); | |
530 | ||
7256233c | 531 | /* Keep track of whether or not we may need to insert PHI nodes. |
6de9cd9a DN |
532 | |
533 | If we reach here in NEED_PHI_STATE_NO, see if this use is dominated | |
534 | by the single block containing the definition(s) of this variable. If | |
535 | it is, then we remain in NEED_PHI_STATE_NO, otherwise we transition to | |
536 | NEED_PHI_STATE_MAYBE. */ | |
8812aab1 | 537 | if (info->need_phi_state == NEED_PHI_STATE_NO) |
6de9cd9a DN |
538 | { |
539 | int def_block_index = bitmap_first_set_bit (db_p->def_blocks); | |
540 | ||
541 | if (def_block_index == -1 | |
542 | || ! dominated_by_p (CDI_DOMINATORS, bb, | |
543 | BASIC_BLOCK (def_block_index))) | |
8812aab1 | 544 | info->need_phi_state = NEED_PHI_STATE_MAYBE; |
6de9cd9a DN |
545 | } |
546 | else | |
8812aab1 | 547 | info->need_phi_state = NEED_PHI_STATE_MAYBE; |
6de9cd9a DN |
548 | } |
549 | ||
550 | ||
0bca51f0 | 551 | /* Return true if NAME is in OLD_SSA_NAMES. */ |
6de9cd9a | 552 | |
0bca51f0 DN |
553 | static inline bool |
554 | is_old_name (tree name) | |
555 | { | |
84d65814 | 556 | unsigned ver = SSA_NAME_VERSION (name); |
5006671f RG |
557 | if (!new_ssa_names) |
558 | return false; | |
5829cc0f | 559 | return (ver < SBITMAP_SIZE (new_ssa_names) |
d7c028c0 | 560 | && bitmap_bit_p (old_ssa_names, ver)); |
0bca51f0 DN |
561 | } |
562 | ||
563 | ||
564 | /* Return true if NAME is in NEW_SSA_NAMES. */ | |
34eb8991 | 565 | |
0bca51f0 DN |
566 | static inline bool |
567 | is_new_name (tree name) | |
568 | { | |
84d65814 | 569 | unsigned ver = SSA_NAME_VERSION (name); |
5006671f RG |
570 | if (!new_ssa_names) |
571 | return false; | |
5829cc0f | 572 | return (ver < SBITMAP_SIZE (new_ssa_names) |
d7c028c0 | 573 | && bitmap_bit_p (new_ssa_names, ver)); |
6de9cd9a DN |
574 | } |
575 | ||
7256233c | 576 | |
82d6e6fc | 577 | /* Return the names replaced by NEW_TREE (i.e., REPL_TBL[NEW_TREE].SET). */ |
0bca51f0 DN |
578 | |
579 | static inline bitmap | |
82d6e6fc | 580 | names_replaced_by (tree new_tree) |
0bca51f0 | 581 | { |
891f2df6 | 582 | return get_ssa_name_ann (new_tree)->repl_set; |
0bca51f0 DN |
583 | } |
584 | ||
585 | ||
82d6e6fc | 586 | /* Add OLD to REPL_TBL[NEW_TREE].SET. */ |
0bca51f0 DN |
587 | |
588 | static inline void | |
82d6e6fc | 589 | add_to_repl_tbl (tree new_tree, tree old) |
0bca51f0 | 590 | { |
891f2df6 RG |
591 | bitmap *set = &get_ssa_name_ann (new_tree)->repl_set; |
592 | if (!*set) | |
593 | *set = BITMAP_ALLOC (&update_ssa_obstack); | |
594 | bitmap_set_bit (*set, SSA_NAME_VERSION (old)); | |
0bca51f0 DN |
595 | } |
596 | ||
597 | ||
82d6e6fc | 598 | /* Add a new mapping NEW_TREE -> OLD REPL_TBL. Every entry N_i in REPL_TBL |
0bca51f0 DN |
599 | represents the set of names O_1 ... O_j replaced by N_i. This is |
600 | used by update_ssa and its helpers to introduce new SSA names in an | |
601 | already formed SSA web. */ | |
602 | ||
603 | static void | |
82d6e6fc | 604 | add_new_name_mapping (tree new_tree, tree old) |
0bca51f0 | 605 | { |
82d6e6fc | 606 | /* OLD and NEW_TREE must be different SSA names for the same symbol. */ |
4ad14919 RG |
607 | gcc_checking_assert (new_tree != old |
608 | && SSA_NAME_VAR (new_tree) == SSA_NAME_VAR (old)); | |
84d65814 | 609 | |
38635499 DN |
610 | /* We may need to grow NEW_SSA_NAMES and OLD_SSA_NAMES because our |
611 | caller may have created new names since the set was created. */ | |
5829cc0f | 612 | if (SBITMAP_SIZE (new_ssa_names) <= num_ssa_names - 1) |
38635499 DN |
613 | { |
614 | unsigned int new_sz = num_ssa_names + NAME_SETS_GROWTH_FACTOR; | |
615 | new_ssa_names = sbitmap_resize (new_ssa_names, new_sz, 0); | |
616 | old_ssa_names = sbitmap_resize (old_ssa_names, new_sz, 0); | |
0bca51f0 DN |
617 | } |
618 | ||
0bca51f0 | 619 | /* Update the REPL_TBL table. */ |
82d6e6fc | 620 | add_to_repl_tbl (new_tree, old); |
d00ad49b | 621 | |
0bca51f0 | 622 | /* If OLD had already been registered as a new name, then all the |
82d6e6fc | 623 | names that OLD replaces should also be replaced by NEW_TREE. */ |
0bca51f0 | 624 | if (is_new_name (old)) |
82d6e6fc | 625 | bitmap_ior_into (names_replaced_by (new_tree), names_replaced_by (old)); |
0bca51f0 | 626 | |
82d6e6fc | 627 | /* Register NEW_TREE and OLD in NEW_SSA_NAMES and OLD_SSA_NAMES, |
0bca51f0 | 628 | respectively. */ |
d7c028c0 LC |
629 | bitmap_set_bit (new_ssa_names, SSA_NAME_VERSION (new_tree)); |
630 | bitmap_set_bit (old_ssa_names, SSA_NAME_VERSION (old)); | |
d00ad49b | 631 | } |
6de9cd9a | 632 | |
6de9cd9a | 633 | |
7256233c DN |
634 | /* Call back for walk_dominator_tree used to collect definition sites |
635 | for every variable in the function. For every statement S in block | |
636 | BB: | |
6de9cd9a | 637 | |
f47c96aa | 638 | 1- Variables defined by S in the DEFS of S are marked in the bitmap |
ccf5c864 | 639 | KILLS. |
6de9cd9a | 640 | |
7256233c | 641 | 2- If S uses a variable VAR and there is no preceding kill of VAR, |
7b71de26 | 642 | then it is marked in the LIVEIN_BLOCKS bitmap associated with VAR. |
6de9cd9a | 643 | |
7256233c DN |
644 | This information is used to determine which variables are live |
645 | across block boundaries to reduce the number of PHI nodes | |
646 | we create. */ | |
6de9cd9a | 647 | |
7256233c | 648 | static void |
ccf5c864 | 649 | mark_def_sites (basic_block bb, gimple stmt, bitmap kills) |
7256233c | 650 | { |
726a989a | 651 | tree def; |
7256233c | 652 | use_operand_p use_p; |
7256233c DN |
653 | ssa_op_iter iter; |
654 | ||
726a989a RB |
655 | /* Since this is the first time that we rewrite the program into SSA |
656 | form, force an operand scan on every statement. */ | |
726a989a | 657 | update_stmt (stmt); |
7256233c | 658 | |
4ad14919 | 659 | gcc_checking_assert (blocks_to_update == NULL); |
726a989a RB |
660 | set_register_defs (stmt, false); |
661 | set_rewrite_uses (stmt, false); | |
7256233c | 662 | |
b5b8b0ac | 663 | if (is_gimple_debug (stmt)) |
ddb555ed JJ |
664 | { |
665 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) | |
666 | { | |
667 | tree sym = USE_FROM_PTR (use_p); | |
4ad14919 | 668 | gcc_checking_assert (DECL_P (sym)); |
ddb555ed JJ |
669 | set_rewrite_uses (stmt, true); |
670 | } | |
671 | if (rewrite_uses_p (stmt)) | |
d7c028c0 | 672 | bitmap_set_bit (interesting_blocks, bb->index); |
ddb555ed JJ |
673 | return; |
674 | } | |
b5b8b0ac | 675 | |
7256233c DN |
676 | /* If a variable is used before being set, then the variable is live |
677 | across a block boundary, so mark it live-on-entry to BB. */ | |
39c58b3a | 678 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) |
7256233c | 679 | { |
0bca51f0 | 680 | tree sym = USE_FROM_PTR (use_p); |
4ad14919 | 681 | gcc_checking_assert (DECL_P (sym)); |
a3648cfc | 682 | if (!bitmap_bit_p (kills, DECL_UID (sym))) |
0bca51f0 | 683 | set_livein_block (sym, bb); |
726a989a | 684 | set_rewrite_uses (stmt, true); |
7256233c | 685 | } |
b8698a0f | 686 | |
38635499 DN |
687 | /* Now process the defs. Mark BB as the definition block and add |
688 | each def to the set of killed symbols. */ | |
39c58b3a | 689 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) |
7256233c | 690 | { |
4ad14919 | 691 | gcc_checking_assert (DECL_P (def)); |
0bca51f0 | 692 | set_def_block (def, bb, false); |
a3648cfc | 693 | bitmap_set_bit (kills, DECL_UID (def)); |
726a989a | 694 | set_register_defs (stmt, true); |
7256233c | 695 | } |
0bca51f0 DN |
696 | |
697 | /* If we found the statement interesting then also mark the block BB | |
698 | as interesting. */ | |
726a989a | 699 | if (rewrite_uses_p (stmt) || register_defs_p (stmt)) |
d7c028c0 | 700 | bitmap_set_bit (interesting_blocks, bb->index); |
7256233c DN |
701 | } |
702 | ||
f074ff6c ZD |
703 | /* Structure used by prune_unused_phi_nodes to record bounds of the intervals |
704 | in the dfs numbering of the dominance tree. */ | |
705 | ||
706 | struct dom_dfsnum | |
707 | { | |
708 | /* Basic block whose index this entry corresponds to. */ | |
709 | unsigned bb_index; | |
710 | ||
711 | /* The dfs number of this node. */ | |
712 | unsigned dfs_num; | |
713 | }; | |
714 | ||
715 | /* Compares two entries of type struct dom_dfsnum by dfs_num field. Callback | |
716 | for qsort. */ | |
717 | ||
718 | static int | |
719 | cmp_dfsnum (const void *a, const void *b) | |
720 | { | |
3d9a9f94 KG |
721 | const struct dom_dfsnum *const da = (const struct dom_dfsnum *) a; |
722 | const struct dom_dfsnum *const db = (const struct dom_dfsnum *) b; | |
f074ff6c ZD |
723 | |
724 | return (int) da->dfs_num - (int) db->dfs_num; | |
725 | } | |
726 | ||
727 | /* Among the intervals starting at the N points specified in DEFS, find | |
728 | the one that contains S, and return its bb_index. */ | |
729 | ||
730 | static unsigned | |
731 | find_dfsnum_interval (struct dom_dfsnum *defs, unsigned n, unsigned s) | |
732 | { | |
733 | unsigned f = 0, t = n, m; | |
734 | ||
735 | while (t > f + 1) | |
736 | { | |
737 | m = (f + t) / 2; | |
738 | if (defs[m].dfs_num <= s) | |
739 | f = m; | |
740 | else | |
741 | t = m; | |
742 | } | |
743 | ||
744 | return defs[f].bb_index; | |
745 | } | |
746 | ||
747 | /* Clean bits from PHIS for phi nodes whose value cannot be used in USES. | |
748 | KILLS is a bitmap of blocks where the value is defined before any use. */ | |
749 | ||
750 | static void | |
751 | prune_unused_phi_nodes (bitmap phis, bitmap kills, bitmap uses) | |
752 | { | |
9771b263 | 753 | vec<int> worklist; |
f074ff6c ZD |
754 | bitmap_iterator bi; |
755 | unsigned i, b, p, u, top; | |
756 | bitmap live_phis; | |
757 | basic_block def_bb, use_bb; | |
758 | edge e; | |
759 | edge_iterator ei; | |
760 | bitmap to_remove; | |
761 | struct dom_dfsnum *defs; | |
762 | unsigned n_defs, adef; | |
763 | ||
764 | if (bitmap_empty_p (uses)) | |
765 | { | |
766 | bitmap_clear (phis); | |
767 | return; | |
768 | } | |
769 | ||
770 | /* The phi must dominate a use, or an argument of a live phi. Also, we | |
771 | do not create any phi nodes in def blocks, unless they are also livein. */ | |
772 | to_remove = BITMAP_ALLOC (NULL); | |
773 | bitmap_and_compl (to_remove, kills, uses); | |
774 | bitmap_and_compl_into (phis, to_remove); | |
775 | if (bitmap_empty_p (phis)) | |
776 | { | |
777 | BITMAP_FREE (to_remove); | |
778 | return; | |
779 | } | |
780 | ||
781 | /* We want to remove the unnecessary phi nodes, but we do not want to compute | |
782 | liveness information, as that may be linear in the size of CFG, and if | |
783 | there are lot of different variables to rewrite, this may lead to quadratic | |
784 | behavior. | |
785 | ||
786 | Instead, we basically emulate standard dce. We put all uses to worklist, | |
787 | then for each of them find the nearest def that dominates them. If this | |
788 | def is a phi node, we mark it live, and if it was not live before, we | |
789 | add the predecessors of its basic block to the worklist. | |
b8698a0f | 790 | |
f074ff6c ZD |
791 | To quickly locate the nearest def that dominates use, we use dfs numbering |
792 | of the dominance tree (that is already available in order to speed up | |
793 | queries). For each def, we have the interval given by the dfs number on | |
794 | entry to and on exit from the corresponding subtree in the dominance tree. | |
795 | The nearest dominator for a given use is the smallest of these intervals | |
796 | that contains entry and exit dfs numbers for the basic block with the use. | |
797 | If we store the bounds for all the uses to an array and sort it, we can | |
798 | locate the nearest dominating def in logarithmic time by binary search.*/ | |
799 | bitmap_ior (to_remove, kills, phis); | |
800 | n_defs = bitmap_count_bits (to_remove); | |
801 | defs = XNEWVEC (struct dom_dfsnum, 2 * n_defs + 1); | |
802 | defs[0].bb_index = 1; | |
803 | defs[0].dfs_num = 0; | |
804 | adef = 1; | |
805 | EXECUTE_IF_SET_IN_BITMAP (to_remove, 0, i, bi) | |
806 | { | |
807 | def_bb = BASIC_BLOCK (i); | |
808 | defs[adef].bb_index = i; | |
809 | defs[adef].dfs_num = bb_dom_dfs_in (CDI_DOMINATORS, def_bb); | |
810 | defs[adef + 1].bb_index = i; | |
811 | defs[adef + 1].dfs_num = bb_dom_dfs_out (CDI_DOMINATORS, def_bb); | |
812 | adef += 2; | |
813 | } | |
814 | BITMAP_FREE (to_remove); | |
815 | gcc_assert (adef == 2 * n_defs + 1); | |
816 | qsort (defs, adef, sizeof (struct dom_dfsnum), cmp_dfsnum); | |
817 | gcc_assert (defs[0].bb_index == 1); | |
818 | ||
819 | /* Now each DEFS entry contains the number of the basic block to that the | |
820 | dfs number corresponds. Change them to the number of basic block that | |
821 | corresponds to the interval following the dfs number. Also, for the | |
822 | dfs_out numbers, increase the dfs number by one (so that it corresponds | |
823 | to the start of the following interval, not to the end of the current | |
824 | one). We use WORKLIST as a stack. */ | |
9771b263 DN |
825 | worklist.create (n_defs + 1); |
826 | worklist.quick_push (1); | |
f074ff6c ZD |
827 | top = 1; |
828 | n_defs = 1; | |
829 | for (i = 1; i < adef; i++) | |
830 | { | |
831 | b = defs[i].bb_index; | |
832 | if (b == top) | |
833 | { | |
834 | /* This is a closing element. Interval corresponding to the top | |
835 | of the stack after removing it follows. */ | |
9771b263 DN |
836 | worklist.pop (); |
837 | top = worklist[worklist.length () - 1]; | |
f074ff6c ZD |
838 | defs[n_defs].bb_index = top; |
839 | defs[n_defs].dfs_num = defs[i].dfs_num + 1; | |
840 | } | |
841 | else | |
842 | { | |
843 | /* Opening element. Nothing to do, just push it to the stack and move | |
844 | it to the correct position. */ | |
845 | defs[n_defs].bb_index = defs[i].bb_index; | |
846 | defs[n_defs].dfs_num = defs[i].dfs_num; | |
9771b263 | 847 | worklist.quick_push (b); |
f074ff6c ZD |
848 | top = b; |
849 | } | |
850 | ||
851 | /* If this interval starts at the same point as the previous one, cancel | |
852 | the previous one. */ | |
853 | if (defs[n_defs].dfs_num == defs[n_defs - 1].dfs_num) | |
854 | defs[n_defs - 1].bb_index = defs[n_defs].bb_index; | |
855 | else | |
856 | n_defs++; | |
857 | } | |
9771b263 DN |
858 | worklist.pop (); |
859 | gcc_assert (worklist.is_empty ()); | |
f074ff6c ZD |
860 | |
861 | /* Now process the uses. */ | |
862 | live_phis = BITMAP_ALLOC (NULL); | |
863 | EXECUTE_IF_SET_IN_BITMAP (uses, 0, i, bi) | |
864 | { | |
9771b263 | 865 | worklist.safe_push (i); |
f074ff6c ZD |
866 | } |
867 | ||
9771b263 | 868 | while (!worklist.is_empty ()) |
f074ff6c | 869 | { |
9771b263 | 870 | b = worklist.pop (); |
f074ff6c ZD |
871 | if (b == ENTRY_BLOCK) |
872 | continue; | |
873 | ||
874 | /* If there is a phi node in USE_BB, it is made live. Otherwise, | |
875 | find the def that dominates the immediate dominator of USE_BB | |
876 | (the kill in USE_BB does not dominate the use). */ | |
877 | if (bitmap_bit_p (phis, b)) | |
878 | p = b; | |
879 | else | |
880 | { | |
881 | use_bb = get_immediate_dominator (CDI_DOMINATORS, BASIC_BLOCK (b)); | |
882 | p = find_dfsnum_interval (defs, n_defs, | |
883 | bb_dom_dfs_in (CDI_DOMINATORS, use_bb)); | |
884 | if (!bitmap_bit_p (phis, p)) | |
885 | continue; | |
886 | } | |
887 | ||
888 | /* If the phi node is already live, there is nothing to do. */ | |
fcaa4ca4 | 889 | if (!bitmap_set_bit (live_phis, p)) |
f074ff6c ZD |
890 | continue; |
891 | ||
fcaa4ca4 | 892 | /* Add the new uses to the worklist. */ |
f074ff6c ZD |
893 | def_bb = BASIC_BLOCK (p); |
894 | FOR_EACH_EDGE (e, ei, def_bb->preds) | |
895 | { | |
896 | u = e->src->index; | |
897 | if (bitmap_bit_p (uses, u)) | |
898 | continue; | |
899 | ||
1e5787ef ZD |
900 | /* In case there is a kill directly in the use block, do not record |
901 | the use (this is also necessary for correctness, as we assume that | |
902 | uses dominated by a def directly in their block have been filtered | |
903 | out before). */ | |
904 | if (bitmap_bit_p (kills, u)) | |
905 | continue; | |
906 | ||
f074ff6c | 907 | bitmap_set_bit (uses, u); |
9771b263 | 908 | worklist.safe_push (u); |
f074ff6c ZD |
909 | } |
910 | } | |
911 | ||
9771b263 | 912 | worklist.release (); |
f074ff6c ZD |
913 | bitmap_copy (phis, live_phis); |
914 | BITMAP_FREE (live_phis); | |
915 | free (defs); | |
916 | } | |
7256233c | 917 | |
7256233c DN |
918 | /* Return the set of blocks where variable VAR is defined and the blocks |
919 | where VAR is live on entry (livein). Return NULL, if no entry is | |
920 | found in DEF_BLOCKS. */ | |
921 | ||
922 | static inline struct def_blocks_d * | |
923 | find_def_blocks_for (tree var) | |
924 | { | |
8812aab1 | 925 | def_blocks_p p = &get_common_info (var)->def_blocks; |
b4e209fd RG |
926 | if (!p->def_blocks) |
927 | return NULL; | |
928 | return p; | |
7256233c DN |
929 | } |
930 | ||
931 | ||
2ce79879 ZD |
932 | /* Marks phi node PHI in basic block BB for rewrite. */ |
933 | ||
934 | static void | |
726a989a | 935 | mark_phi_for_rewrite (basic_block bb, gimple phi) |
2ce79879 | 936 | { |
726a989a | 937 | gimple_vec phis; |
580b2c2e | 938 | unsigned n, idx = bb->index; |
2ce79879 | 939 | |
726a989a | 940 | if (rewrite_uses_p (phi)) |
2ce79879 | 941 | return; |
38635499 | 942 | |
726a989a | 943 | set_rewrite_uses (phi, true); |
2ce79879 ZD |
944 | |
945 | if (!blocks_with_phis_to_rewrite) | |
946 | return; | |
947 | ||
948 | bitmap_set_bit (blocks_with_phis_to_rewrite, idx); | |
580b2c2e SB |
949 | |
950 | n = (unsigned) last_basic_block + 1; | |
9771b263 DN |
951 | if (phis_to_rewrite.length () < n) |
952 | phis_to_rewrite.safe_grow_cleared (n); | |
2ce79879 | 953 | |
9771b263 DN |
954 | phis = phis_to_rewrite[idx]; |
955 | phis.reserve (10); | |
2ce79879 | 956 | |
9771b263 DN |
957 | phis.safe_push (phi); |
958 | phis_to_rewrite[idx] = phis; | |
2ce79879 ZD |
959 | } |
960 | ||
7256233c | 961 | /* Insert PHI nodes for variable VAR using the iterated dominance |
0bca51f0 | 962 | frontier given in PHI_INSERTION_POINTS. If UPDATE_P is true, this |
38635499 DN |
963 | function assumes that the caller is incrementally updating the |
964 | existing SSA form, in which case VAR may be an SSA name instead of | |
965 | a symbol. | |
0bca51f0 DN |
966 | |
967 | PHI_INSERTION_POINTS is updated to reflect nodes that already had a | |
968 | PHI node for VAR. On exit, only the nodes that received a PHI node | |
969 | for VAR will be present in PHI_INSERTION_POINTS. */ | |
7256233c DN |
970 | |
971 | static void | |
0bca51f0 | 972 | insert_phi_nodes_for (tree var, bitmap phi_insertion_points, bool update_p) |
7256233c DN |
973 | { |
974 | unsigned bb_index; | |
975 | edge e; | |
726a989a | 976 | gimple phi; |
7256233c DN |
977 | basic_block bb; |
978 | bitmap_iterator bi; | |
4ad14919 | 979 | struct def_blocks_d *def_map = find_def_blocks_for (var); |
7256233c DN |
980 | |
981 | /* Remove the blocks where we already have PHI nodes for VAR. */ | |
982 | bitmap_and_compl_into (phi_insertion_points, def_map->phi_blocks); | |
983 | ||
f074ff6c ZD |
984 | /* Remove obviously useless phi nodes. */ |
985 | prune_unused_phi_nodes (phi_insertion_points, def_map->def_blocks, | |
986 | def_map->livein_blocks); | |
7256233c DN |
987 | |
988 | /* And insert the PHI nodes. */ | |
f074ff6c | 989 | EXECUTE_IF_SET_IN_BITMAP (phi_insertion_points, 0, bb_index, bi) |
7256233c DN |
990 | { |
991 | bb = BASIC_BLOCK (bb_index); | |
95dd3097 ZD |
992 | if (update_p) |
993 | mark_block_for_update (bb); | |
7256233c | 994 | |
fa5556de RB |
995 | if (dump_file && (dump_flags & TDF_DETAILS)) |
996 | { | |
997 | fprintf (dump_file, "creating PHI node in block #%d for ", bb_index); | |
998 | print_generic_expr (dump_file, var, TDF_SLIM); | |
999 | fprintf (dump_file, "\n"); | |
1000 | } | |
726a989a | 1001 | phi = NULL; |
38635499 DN |
1002 | |
1003 | if (TREE_CODE (var) == SSA_NAME) | |
7256233c | 1004 | { |
84d65814 DN |
1005 | /* If we are rewriting SSA names, create the LHS of the PHI |
1006 | node by duplicating VAR. This is useful in the case of | |
1007 | pointers, to also duplicate pointer attributes (alias | |
1008 | information, in particular). */ | |
7256233c | 1009 | edge_iterator ei; |
84d65814 | 1010 | tree new_lhs; |
0bca51f0 | 1011 | |
4ad14919 | 1012 | gcc_checking_assert (update_p); |
dcc748dd RG |
1013 | new_lhs = duplicate_ssa_name (var, NULL); |
1014 | phi = create_phi_node (new_lhs, bb); | |
84d65814 | 1015 | add_new_name_mapping (new_lhs, var); |
0bca51f0 DN |
1016 | |
1017 | /* Add VAR to every argument slot of PHI. We need VAR in | |
1018 | every argument so that rewrite_update_phi_arguments knows | |
1019 | which name is this PHI node replacing. If VAR is a | |
1020 | symbol marked for renaming, this is not necessary, the | |
1021 | renamer will use the symbol on the LHS to get its | |
1022 | reaching definition. */ | |
7256233c | 1023 | FOR_EACH_EDGE (e, ei, bb->preds) |
9e227d60 | 1024 | add_phi_arg (phi, var, e, UNKNOWN_LOCATION); |
7256233c | 1025 | } |
84d65814 DN |
1026 | else |
1027 | { | |
b5b8b0ac | 1028 | tree tracked_var; |
3a56edc7 | 1029 | |
4ad14919 | 1030 | gcc_checking_assert (DECL_P (var)); |
e24c4814 | 1031 | phi = create_phi_node (var, bb); |
3a56edc7 AO |
1032 | |
1033 | tracked_var = target_for_debug_bind (var); | |
1034 | if (tracked_var) | |
b5b8b0ac AO |
1035 | { |
1036 | gimple note = gimple_build_debug_bind (tracked_var, | |
1037 | PHI_RESULT (phi), | |
1038 | phi); | |
1039 | gimple_stmt_iterator si = gsi_after_labels (bb); | |
1040 | gsi_insert_before (&si, note, GSI_SAME_STMT); | |
1041 | } | |
84d65814 | 1042 | } |
0bca51f0 DN |
1043 | |
1044 | /* Mark this PHI node as interesting for update_ssa. */ | |
726a989a | 1045 | set_register_defs (phi, true); |
2ce79879 | 1046 | mark_phi_for_rewrite (bb, phi); |
7256233c DN |
1047 | } |
1048 | } | |
1049 | ||
b4e209fd | 1050 | /* Sort var_infos after DECL_UID of their var. */ |
d9ed2fbd RG |
1051 | |
1052 | static int | |
b4e209fd | 1053 | insert_phi_nodes_compare_var_infos (const void *a, const void *b) |
d9ed2fbd | 1054 | { |
b4e209fd RG |
1055 | const struct var_info_d *defa = *(struct var_info_d * const *)a; |
1056 | const struct var_info_d *defb = *(struct var_info_d * const *)b; | |
d9ed2fbd RG |
1057 | if (DECL_UID (defa->var) < DECL_UID (defb->var)) |
1058 | return -1; | |
1059 | else | |
1060 | return 1; | |
1061 | } | |
7256233c | 1062 | |
7256233c DN |
1063 | /* Insert PHI nodes at the dominance frontier of blocks with variable |
1064 | definitions. DFS contains the dominance frontier information for | |
38635499 | 1065 | the flowgraph. */ |
7256233c DN |
1066 | |
1067 | static void | |
0fc555fb | 1068 | insert_phi_nodes (bitmap_head *dfs) |
7256233c | 1069 | { |
bf190e8d | 1070 | hash_table <var_info_hasher>::iterator hi; |
d9ed2fbd | 1071 | unsigned i; |
b4e209fd | 1072 | var_info_p info; |
9771b263 | 1073 | vec<var_info_p> vars; |
7256233c DN |
1074 | |
1075 | timevar_push (TV_TREE_INSERT_PHI_NODES); | |
b8698a0f | 1076 | |
bf190e8d LC |
1077 | vars.create (var_infos.elements ()); |
1078 | FOR_EACH_HASH_TABLE_ELEMENT (var_infos, info, var_info_p, hi) | |
8812aab1 | 1079 | if (info->info.need_phi_state != NEED_PHI_STATE_NO) |
9771b263 | 1080 | vars.quick_push (info); |
d9ed2fbd | 1081 | |
e68c7b43 RG |
1082 | /* Do two stages to avoid code generation differences for UID |
1083 | differences but no UID ordering differences. */ | |
9771b263 | 1084 | vars.qsort (insert_phi_nodes_compare_var_infos); |
e68c7b43 | 1085 | |
9771b263 | 1086 | FOR_EACH_VEC_ELT (vars, i, info) |
5f240ec4 | 1087 | { |
8812aab1 | 1088 | bitmap idf = compute_idf (info->info.def_blocks.def_blocks, dfs); |
b4e209fd | 1089 | insert_phi_nodes_for (info->var, idf, false); |
e68c7b43 RG |
1090 | BITMAP_FREE (idf); |
1091 | } | |
1092 | ||
9771b263 | 1093 | vars.release (); |
e68c7b43 | 1094 | |
6de9cd9a DN |
1095 | timevar_pop (TV_TREE_INSERT_PHI_NODES); |
1096 | } | |
1097 | ||
1098 | ||
38635499 DN |
1099 | /* Push SYM's current reaching definition into BLOCK_DEFS_STACK and |
1100 | register DEF (an SSA_NAME) to be a new definition for SYM. */ | |
7256233c | 1101 | |
cfaab3a9 | 1102 | static void |
38635499 | 1103 | register_new_def (tree def, tree sym) |
7256233c | 1104 | { |
8812aab1 | 1105 | common_info_p info = get_common_info (sym); |
7256233c | 1106 | tree currdef; |
b8698a0f | 1107 | |
7256233c DN |
1108 | /* If this variable is set in a single basic block and all uses are |
1109 | dominated by the set(s) in that single basic block, then there is | |
1110 | no reason to record anything for this variable in the block local | |
1111 | definition stacks. Doing so just wastes time and memory. | |
1112 | ||
1113 | This is the same test to prune the set of variables which may | |
1114 | need PHI nodes. So we just use that information since it's already | |
1115 | computed and available for us to use. */ | |
8812aab1 | 1116 | if (info->need_phi_state == NEED_PHI_STATE_NO) |
7256233c | 1117 | { |
8812aab1 | 1118 | info->current_def = def; |
7256233c DN |
1119 | return; |
1120 | } | |
1121 | ||
8812aab1 | 1122 | currdef = info->current_def; |
7256233c | 1123 | |
38635499 DN |
1124 | /* If SYM is not a GIMPLE register, then CURRDEF may be a name whose |
1125 | SSA_NAME_VAR is not necessarily SYM. In this case, also push SYM | |
1126 | in the stack so that we know which symbol is being defined by | |
1127 | this SSA name when we unwind the stack. */ | |
1128 | if (currdef && !is_gimple_reg (sym)) | |
9771b263 | 1129 | block_defs_stack.safe_push (sym); |
7256233c | 1130 | |
38635499 DN |
1131 | /* Push the current reaching definition into BLOCK_DEFS_STACK. This |
1132 | stack is later used by the dominator tree callbacks to restore | |
1133 | the reaching definitions for all the variables defined in the | |
1134 | block after a recursive visit to all its immediately dominated | |
1135 | blocks. If there is no current reaching definition, then just | |
1136 | record the underlying _DECL node. */ | |
9771b263 | 1137 | block_defs_stack.safe_push (currdef ? currdef : sym); |
38635499 DN |
1138 | |
1139 | /* Set the current reaching definition for SYM to be DEF. */ | |
8812aab1 | 1140 | info->current_def = def; |
7256233c DN |
1141 | } |
1142 | ||
1143 | ||
6de9cd9a DN |
1144 | /* Perform a depth-first traversal of the dominator tree looking for |
1145 | variables to rename. BB is the block where to start searching. | |
1146 | Renaming is a five step process: | |
1147 | ||
1148 | 1- Every definition made by PHI nodes at the start of the blocks is | |
1149 | registered as the current definition for the corresponding variable. | |
1150 | ||
1151 | 2- Every statement in BB is rewritten. USE and VUSE operands are | |
1152 | rewritten with their corresponding reaching definition. DEF and | |
1153 | VDEF targets are registered as new definitions. | |
b8698a0f | 1154 | |
6de9cd9a DN |
1155 | 3- All the PHI nodes in successor blocks of BB are visited. The |
1156 | argument corresponding to BB is replaced with its current reaching | |
1157 | definition. | |
1158 | ||
1159 | 4- Recursively rewrite every dominator child block of BB. | |
1160 | ||
1161 | 5- Restore (in reverse order) the current reaching definition for every | |
1162 | new definition introduced in this block. This is done so that when | |
1163 | we return from the recursive call, all the current reaching | |
1164 | definitions are restored to the names that were valid in the | |
1165 | dominator parent of BB. */ | |
1166 | ||
7256233c | 1167 | /* Return the current definition for variable VAR. If none is found, |
38635499 | 1168 | create a new SSA name to act as the zeroth definition for VAR. */ |
5f240ec4 | 1169 | |
7256233c DN |
1170 | static tree |
1171 | get_reaching_def (tree var) | |
1172 | { | |
8812aab1 | 1173 | common_info_p info = get_common_info (var); |
38635499 | 1174 | tree currdef; |
b8698a0f | 1175 | |
7256233c | 1176 | /* Lookup the current reaching definition for VAR. */ |
8812aab1 | 1177 | currdef = info->current_def; |
5f240ec4 | 1178 | |
7256233c DN |
1179 | /* If there is no reaching definition for VAR, create and register a |
1180 | default definition for it (if needed). */ | |
38635499 | 1181 | if (currdef == NULL_TREE) |
7256233c | 1182 | { |
38635499 | 1183 | tree sym = DECL_P (var) ? var : SSA_NAME_VAR (var); |
32244553 | 1184 | currdef = get_or_create_ssa_default_def (cfun, sym); |
7256233c DN |
1185 | } |
1186 | ||
1187 | /* Return the current reaching definition for VAR, or the default | |
1188 | definition, if we had to create one. */ | |
38635499 | 1189 | return currdef; |
7256233c DN |
1190 | } |
1191 | ||
1192 | ||
ddb555ed JJ |
1193 | /* Helper function for rewrite_stmt. Rewrite uses in a debug stmt. */ |
1194 | ||
1195 | static void | |
1196 | rewrite_debug_stmt_uses (gimple stmt) | |
1197 | { | |
1198 | use_operand_p use_p; | |
1199 | ssa_op_iter iter; | |
1200 | bool update = false; | |
1201 | ||
1202 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) | |
1203 | { | |
5f564b8f | 1204 | tree var = USE_FROM_PTR (use_p), def; |
8812aab1 | 1205 | common_info_p info = get_common_info (var); |
4ad14919 | 1206 | gcc_checking_assert (DECL_P (var)); |
8812aab1 | 1207 | def = info->current_def; |
5f564b8f | 1208 | if (!def) |
ddb555ed JJ |
1209 | { |
1210 | if (TREE_CODE (var) == PARM_DECL && single_succ_p (ENTRY_BLOCK_PTR)) | |
1211 | { | |
1212 | gimple_stmt_iterator gsi | |
1213 | = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR)); | |
1214 | int lim; | |
1215 | /* Search a few source bind stmts at the start of first bb to | |
1216 | see if a DEBUG_EXPR_DECL can't be reused. */ | |
1217 | for (lim = 32; | |
1218 | !gsi_end_p (gsi) && lim > 0; | |
1219 | gsi_next (&gsi), lim--) | |
1220 | { | |
1221 | gimple gstmt = gsi_stmt (gsi); | |
1222 | if (!gimple_debug_source_bind_p (gstmt)) | |
1223 | break; | |
1224 | if (gimple_debug_source_bind_get_value (gstmt) == var) | |
1225 | { | |
1226 | def = gimple_debug_source_bind_get_var (gstmt); | |
1227 | if (TREE_CODE (def) == DEBUG_EXPR_DECL) | |
1228 | break; | |
1229 | else | |
1230 | def = NULL_TREE; | |
1231 | } | |
1232 | } | |
1233 | /* If not, add a new source bind stmt. */ | |
1234 | if (def == NULL_TREE) | |
1235 | { | |
1236 | gimple def_temp; | |
1237 | def = make_node (DEBUG_EXPR_DECL); | |
1238 | def_temp = gimple_build_debug_source_bind (def, var, NULL); | |
1239 | DECL_ARTIFICIAL (def) = 1; | |
1240 | TREE_TYPE (def) = TREE_TYPE (var); | |
1241 | DECL_MODE (def) = DECL_MODE (var); | |
1242 | gsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR)); | |
1243 | gsi_insert_before (&gsi, def_temp, GSI_SAME_STMT); | |
1244 | } | |
1245 | update = true; | |
1246 | } | |
1247 | } | |
1248 | else | |
15923c25 | 1249 | { |
8812aab1 | 1250 | /* Check if info->current_def can be trusted. */ |
5f564b8f MM |
1251 | basic_block bb = gimple_bb (stmt); |
1252 | basic_block def_bb | |
1253 | = SSA_NAME_IS_DEFAULT_DEF (def) | |
1254 | ? NULL : gimple_bb (SSA_NAME_DEF_STMT (def)); | |
1255 | ||
1256 | /* If definition is in current bb, it is fine. */ | |
1257 | if (bb == def_bb) | |
1258 | ; | |
1259 | /* If definition bb doesn't dominate the current bb, | |
1260 | it can't be used. */ | |
1261 | else if (def_bb && !dominated_by_p (CDI_DOMINATORS, bb, def_bb)) | |
1262 | def = NULL; | |
1263 | /* If there is just one definition and dominates the current | |
1264 | bb, it is fine. */ | |
8812aab1 | 1265 | else if (info->need_phi_state == NEED_PHI_STATE_NO) |
5f564b8f MM |
1266 | ; |
1267 | else | |
15923c25 | 1268 | { |
8812aab1 | 1269 | struct def_blocks_d *db_p = get_def_blocks_for (info); |
15923c25 | 1270 | |
5f564b8f MM |
1271 | /* If there are some non-debug uses in the current bb, |
1272 | it is fine. */ | |
1273 | if (bitmap_bit_p (db_p->livein_blocks, bb->index)) | |
15923c25 | 1274 | ; |
5f564b8f | 1275 | /* Otherwise give up for now. */ |
15923c25 | 1276 | else |
5f564b8f | 1277 | def = NULL; |
15923c25 JJ |
1278 | } |
1279 | } | |
ddb555ed JJ |
1280 | if (def == NULL) |
1281 | { | |
1282 | gimple_debug_bind_reset_value (stmt); | |
1283 | update_stmt (stmt); | |
1284 | return; | |
1285 | } | |
1286 | SET_USE (use_p, def); | |
1287 | } | |
1288 | if (update) | |
1289 | update_stmt (stmt); | |
1290 | } | |
1291 | ||
7256233c DN |
1292 | /* SSA Rewriting Step 2. Rewrite every variable used in each statement in |
1293 | the block with its immediate reaching definitions. Update the current | |
1294 | definition of a variable when a new real or virtual definition is found. */ | |
5f240ec4 ZD |
1295 | |
1296 | static void | |
5f33a4fc | 1297 | rewrite_stmt (gimple_stmt_iterator *si) |
5f240ec4 | 1298 | { |
7256233c DN |
1299 | use_operand_p use_p; |
1300 | def_operand_p def_p; | |
1301 | ssa_op_iter iter; | |
5f33a4fc | 1302 | gimple stmt = gsi_stmt (*si); |
7256233c | 1303 | |
7256233c DN |
1304 | /* If mark_def_sites decided that we don't need to rewrite this |
1305 | statement, ignore it. */ | |
95dd3097 | 1306 | gcc_assert (blocks_to_update == NULL); |
726a989a | 1307 | if (!rewrite_uses_p (stmt) && !register_defs_p (stmt)) |
7256233c | 1308 | return; |
5f240ec4 ZD |
1309 | |
1310 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
7256233c DN |
1311 | { |
1312 | fprintf (dump_file, "Renaming statement "); | |
726a989a | 1313 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); |
7256233c DN |
1314 | fprintf (dump_file, "\n"); |
1315 | } | |
5f240ec4 | 1316 | |
38635499 | 1317 | /* Step 1. Rewrite USES in the statement. */ |
726a989a | 1318 | if (rewrite_uses_p (stmt)) |
ddb555ed JJ |
1319 | { |
1320 | if (is_gimple_debug (stmt)) | |
1321 | rewrite_debug_stmt_uses (stmt); | |
1322 | else | |
39c58b3a | 1323 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) |
ddb555ed JJ |
1324 | { |
1325 | tree var = USE_FROM_PTR (use_p); | |
4ad14919 | 1326 | gcc_checking_assert (DECL_P (var)); |
ddb555ed JJ |
1327 | SET_USE (use_p, get_reaching_def (var)); |
1328 | } | |
1329 | } | |
5f240ec4 | 1330 | |
38635499 | 1331 | /* Step 2. Register the statement's DEF operands. */ |
726a989a | 1332 | if (register_defs_p (stmt)) |
39c58b3a | 1333 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_ALL_DEFS) |
0bca51f0 DN |
1334 | { |
1335 | tree var = DEF_FROM_PTR (def_p); | |
5f33a4fc | 1336 | tree name; |
b5b8b0ac | 1337 | tree tracked_var; |
5f33a4fc | 1338 | |
4ad14919 | 1339 | gcc_checking_assert (DECL_P (var)); |
5f33a4fc RG |
1340 | |
1341 | if (gimple_clobber_p (stmt) | |
1342 | && is_gimple_reg (var)) | |
1343 | { | |
1344 | /* If we rewrite a DECL into SSA form then drop its | |
1345 | clobber stmts and replace uses with a new default def. */ | |
4ad14919 RG |
1346 | gcc_checking_assert (TREE_CODE (var) == VAR_DECL |
1347 | && !gimple_vdef (stmt)); | |
5f33a4fc RG |
1348 | gsi_replace (si, gimple_build_nop (), true); |
1349 | register_new_def (get_or_create_ssa_default_def (cfun, var), var); | |
1350 | break; | |
1351 | } | |
1352 | ||
1353 | name = make_ssa_name (var, stmt); | |
b5b8b0ac | 1354 | SET_DEF (def_p, name); |
38635499 | 1355 | register_new_def (DEF_FROM_PTR (def_p), var); |
b5b8b0ac AO |
1356 | |
1357 | tracked_var = target_for_debug_bind (var); | |
1358 | if (tracked_var) | |
1359 | { | |
1360 | gimple note = gimple_build_debug_bind (tracked_var, name, stmt); | |
5f33a4fc | 1361 | gsi_insert_after (si, note, GSI_SAME_STMT); |
b5b8b0ac | 1362 | } |
0bca51f0 | 1363 | } |
5f240ec4 | 1364 | } |
6de9cd9a | 1365 | |
7256233c | 1366 | |
6de9cd9a DN |
1367 | /* SSA Rewriting Step 3. Visit all the successor blocks of BB looking for |
1368 | PHI nodes. For every PHI node found, add a new argument containing the | |
1369 | current reaching definition for the variable and the edge through which | |
471854f8 | 1370 | that definition is reaching the PHI node. */ |
6de9cd9a DN |
1371 | |
1372 | static void | |
ccf5c864 | 1373 | rewrite_add_phi_arguments (basic_block bb) |
6de9cd9a DN |
1374 | { |
1375 | edge e; | |
628f6a4e | 1376 | edge_iterator ei; |
6de9cd9a | 1377 | |
628f6a4e | 1378 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a | 1379 | { |
726a989a RB |
1380 | gimple phi; |
1381 | gimple_stmt_iterator gsi; | |
6de9cd9a | 1382 | |
726a989a RB |
1383 | for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); |
1384 | gsi_next (&gsi)) | |
6de9cd9a | 1385 | { |
ffc5b2bb RB |
1386 | tree currdef, res; |
1387 | location_t loc; | |
f5045c96 | 1388 | |
726a989a | 1389 | phi = gsi_stmt (gsi); |
ffc5b2bb RB |
1390 | res = gimple_phi_result (phi); |
1391 | currdef = get_reaching_def (SSA_NAME_VAR (res)); | |
1392 | /* Virtual operand PHI args do not need a location. */ | |
1393 | if (virtual_operand_p (res)) | |
1394 | loc = UNKNOWN_LOCATION; | |
1395 | else | |
1396 | loc = gimple_location (SSA_NAME_DEF_STMT (currdef)); | |
1397 | add_phi_arg (phi, currdef, e, loc); | |
6de9cd9a DN |
1398 | } |
1399 | } | |
1400 | } | |
1401 | ||
ccf5c864 PB |
1402 | /* SSA Rewriting Step 1. Initialization, create a block local stack |
1403 | of reaching definitions for new SSA names produced in this block | |
1404 | (BLOCK_DEFS). Register new definitions for every PHI node in the | |
1405 | block. */ | |
1406 | ||
1407 | static void | |
1408 | rewrite_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
1409 | basic_block bb) | |
1410 | { | |
ccf5c864 PB |
1411 | gimple_stmt_iterator gsi; |
1412 | ||
1413 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1414 | fprintf (dump_file, "\n\nRenaming block #%d\n\n", bb->index); | |
1415 | ||
1416 | /* Mark the unwind point for this block. */ | |
9771b263 | 1417 | block_defs_stack.safe_push (NULL_TREE); |
ccf5c864 PB |
1418 | |
1419 | /* Step 1. Register new definitions for every PHI node in the block. | |
1420 | Conceptually, all the PHI nodes are executed in parallel and each PHI | |
1421 | node introduces a new version for the associated variable. */ | |
1422 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1423 | { | |
39c58b3a | 1424 | tree result = gimple_phi_result (gsi_stmt (gsi)); |
ccf5c864 PB |
1425 | register_new_def (result, SSA_NAME_VAR (result)); |
1426 | } | |
1427 | ||
1428 | /* Step 2. Rewrite every variable used in each statement in the block | |
1429 | with its immediate reaching definitions. Update the current definition | |
1430 | of a variable when a new real or virtual definition is found. */ | |
d7c028c0 | 1431 | if (bitmap_bit_p (interesting_blocks, bb->index)) |
ccf5c864 | 1432 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
5f33a4fc | 1433 | rewrite_stmt (&gsi); |
ccf5c864 PB |
1434 | |
1435 | /* Step 3. Visit all the successor blocks of BB looking for PHI nodes. | |
1436 | For every PHI node found, add a new argument containing the current | |
1437 | reaching definition for the variable and the edge through which that | |
1438 | definition is reaching the PHI node. */ | |
1439 | rewrite_add_phi_arguments (bb); | |
1440 | } | |
1441 | ||
1442 | ||
7256233c | 1443 | |
38635499 DN |
1444 | /* Called after visiting all the statements in basic block BB and all |
1445 | of its dominator children. Restore CURRDEFS to its original value. */ | |
6de9cd9a DN |
1446 | |
1447 | static void | |
ccf5c864 PB |
1448 | rewrite_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, |
1449 | basic_block bb ATTRIBUTE_UNUSED) | |
6de9cd9a | 1450 | { |
9fae925b | 1451 | /* Restore CURRDEFS to its original state. */ |
9771b263 | 1452 | while (block_defs_stack.length () > 0) |
6de9cd9a | 1453 | { |
9771b263 | 1454 | tree tmp = block_defs_stack.pop (); |
6de9cd9a DN |
1455 | tree saved_def, var; |
1456 | ||
9fae925b JL |
1457 | if (tmp == NULL_TREE) |
1458 | break; | |
1459 | ||
6de9cd9a DN |
1460 | if (TREE_CODE (tmp) == SSA_NAME) |
1461 | { | |
38635499 DN |
1462 | /* If we recorded an SSA_NAME, then make the SSA_NAME the |
1463 | current definition of its underlying variable. Note that | |
1464 | if the SSA_NAME is not for a GIMPLE register, the symbol | |
1465 | being defined is stored in the next slot in the stack. | |
1466 | This mechanism is needed because an SSA name for a | |
1467 | non-register symbol may be the definition for more than | |
1468 | one symbol (e.g., SFTs, aliased variables, etc). */ | |
6de9cd9a DN |
1469 | saved_def = tmp; |
1470 | var = SSA_NAME_VAR (saved_def); | |
38635499 | 1471 | if (!is_gimple_reg (var)) |
9771b263 | 1472 | var = block_defs_stack.pop (); |
6de9cd9a DN |
1473 | } |
1474 | else | |
1475 | { | |
38635499 DN |
1476 | /* If we recorded anything else, it must have been a _DECL |
1477 | node and its current reaching definition must have been | |
1478 | NULL. */ | |
6de9cd9a DN |
1479 | saved_def = NULL; |
1480 | var = tmp; | |
1481 | } | |
b8698a0f | 1482 | |
8812aab1 | 1483 | get_common_info (var)->current_def = saved_def; |
6de9cd9a DN |
1484 | } |
1485 | } | |
1486 | ||
1487 | ||
38635499 DN |
1488 | /* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */ |
1489 | ||
1490 | void | |
1491 | dump_decl_set (FILE *file, bitmap set) | |
1492 | { | |
1493 | if (set) | |
1494 | { | |
3b302421 RG |
1495 | bitmap_iterator bi; |
1496 | unsigned i; | |
38635499 DN |
1497 | |
1498 | fprintf (file, "{ "); | |
1499 | ||
3b302421 | 1500 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) |
38635499 | 1501 | { |
46eb666a | 1502 | fprintf (file, "D.%u", i); |
38635499 DN |
1503 | fprintf (file, " "); |
1504 | } | |
1505 | ||
5006671f | 1506 | fprintf (file, "}"); |
38635499 DN |
1507 | } |
1508 | else | |
5006671f | 1509 | fprintf (file, "NIL"); |
38635499 DN |
1510 | } |
1511 | ||
1512 | ||
1513 | /* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */ | |
1514 | ||
24e47c76 | 1515 | DEBUG_FUNCTION void |
38635499 DN |
1516 | debug_decl_set (bitmap set) |
1517 | { | |
1518 | dump_decl_set (stderr, set); | |
5006671f | 1519 | fprintf (stderr, "\n"); |
38635499 DN |
1520 | } |
1521 | ||
1522 | ||
1523 | /* Dump the renaming stack (block_defs_stack) to FILE. Traverse the | |
1524 | stack up to a maximum of N levels. If N is -1, the whole stack is | |
1525 | dumped. New levels are created when the dominator tree traversal | |
1526 | used for renaming enters a new sub-tree. */ | |
1527 | ||
1528 | void | |
1529 | dump_defs_stack (FILE *file, int n) | |
1530 | { | |
1531 | int i, j; | |
1532 | ||
1533 | fprintf (file, "\n\nRenaming stack"); | |
1534 | if (n > 0) | |
1535 | fprintf (file, " (up to %d levels)", n); | |
1536 | fprintf (file, "\n\n"); | |
1537 | ||
1538 | i = 1; | |
1539 | fprintf (file, "Level %d (current level)\n", i); | |
9771b263 | 1540 | for (j = (int) block_defs_stack.length () - 1; j >= 0; j--) |
38635499 DN |
1541 | { |
1542 | tree name, var; | |
b8698a0f | 1543 | |
9771b263 | 1544 | name = block_defs_stack[j]; |
38635499 DN |
1545 | if (name == NULL_TREE) |
1546 | { | |
1547 | i++; | |
1548 | if (n > 0 && i > n) | |
1549 | break; | |
1550 | fprintf (file, "\nLevel %d\n", i); | |
1551 | continue; | |
1552 | } | |
1553 | ||
1554 | if (DECL_P (name)) | |
1555 | { | |
1556 | var = name; | |
1557 | name = NULL_TREE; | |
1558 | } | |
1559 | else | |
1560 | { | |
1561 | var = SSA_NAME_VAR (name); | |
1562 | if (!is_gimple_reg (var)) | |
1563 | { | |
1564 | j--; | |
9771b263 | 1565 | var = block_defs_stack[j]; |
38635499 DN |
1566 | } |
1567 | } | |
1568 | ||
1569 | fprintf (file, " Previous CURRDEF ("); | |
1570 | print_generic_expr (file, var, 0); | |
1571 | fprintf (file, ") = "); | |
1572 | if (name) | |
1573 | print_generic_expr (file, name, 0); | |
1574 | else | |
1575 | fprintf (file, "<NIL>"); | |
1576 | fprintf (file, "\n"); | |
1577 | } | |
1578 | } | |
1579 | ||
1580 | ||
1581 | /* Dump the renaming stack (block_defs_stack) to stderr. Traverse the | |
1582 | stack up to a maximum of N levels. If N is -1, the whole stack is | |
1583 | dumped. New levels are created when the dominator tree traversal | |
1584 | used for renaming enters a new sub-tree. */ | |
1585 | ||
24e47c76 | 1586 | DEBUG_FUNCTION void |
38635499 DN |
1587 | debug_defs_stack (int n) |
1588 | { | |
1589 | dump_defs_stack (stderr, n); | |
1590 | } | |
1591 | ||
1592 | ||
1593 | /* Dump the current reaching definition of every symbol to FILE. */ | |
1594 | ||
1595 | void | |
1596 | dump_currdefs (FILE *file) | |
1597 | { | |
13714310 | 1598 | unsigned i; |
38635499 DN |
1599 | tree var; |
1600 | ||
9771b263 | 1601 | if (symbols_to_rename.is_empty ()) |
13714310 RG |
1602 | return; |
1603 | ||
38635499 | 1604 | fprintf (file, "\n\nCurrent reaching definitions\n\n"); |
9771b263 | 1605 | FOR_EACH_VEC_ELT (symbols_to_rename, i, var) |
13714310 | 1606 | { |
8812aab1 | 1607 | common_info_p info = get_common_info (var); |
13714310 RG |
1608 | fprintf (file, "CURRDEF ("); |
1609 | print_generic_expr (file, var, 0); | |
1610 | fprintf (file, ") = "); | |
8812aab1 RG |
1611 | if (info->current_def) |
1612 | print_generic_expr (file, info->current_def, 0); | |
13714310 RG |
1613 | else |
1614 | fprintf (file, "<NIL>"); | |
1615 | fprintf (file, "\n"); | |
1616 | } | |
38635499 DN |
1617 | } |
1618 | ||
1619 | ||
1620 | /* Dump the current reaching definition of every symbol to stderr. */ | |
1621 | ||
24e47c76 | 1622 | DEBUG_FUNCTION void |
38635499 DN |
1623 | debug_currdefs (void) |
1624 | { | |
1625 | dump_currdefs (stderr); | |
1626 | } | |
1627 | ||
1628 | ||
6de9cd9a DN |
1629 | /* Dump SSA information to FILE. */ |
1630 | ||
1631 | void | |
1632 | dump_tree_ssa (FILE *file) | |
1633 | { | |
6de9cd9a | 1634 | const char *funcname |
673fda6b | 1635 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
6de9cd9a | 1636 | |
38635499 | 1637 | fprintf (file, "SSA renaming information for %s\n\n", funcname); |
6de9cd9a | 1638 | |
b4e209fd | 1639 | dump_var_infos (file); |
38635499 DN |
1640 | dump_defs_stack (file, -1); |
1641 | dump_currdefs (file); | |
1642 | dump_tree_ssa_stats (file); | |
6de9cd9a DN |
1643 | } |
1644 | ||
1645 | ||
1646 | /* Dump SSA information to stderr. */ | |
1647 | ||
24e47c76 | 1648 | DEBUG_FUNCTION void |
6de9cd9a DN |
1649 | debug_tree_ssa (void) |
1650 | { | |
1651 | dump_tree_ssa (stderr); | |
1652 | } | |
1653 | ||
1654 | ||
7256233c DN |
1655 | /* Dump statistics for the hash table HTAB. */ |
1656 | ||
1657 | static void | |
bf190e8d | 1658 | htab_statistics (FILE *file, hash_table <var_info_hasher> htab) |
7256233c DN |
1659 | { |
1660 | fprintf (file, "size %ld, %ld elements, %f collision/search ratio\n", | |
bf190e8d LC |
1661 | (long) htab.size (), |
1662 | (long) htab.elements (), | |
1663 | htab.collisions ()); | |
7256233c DN |
1664 | } |
1665 | ||
1666 | ||
6de9cd9a DN |
1667 | /* Dump SSA statistics on FILE. */ |
1668 | ||
1669 | void | |
1670 | dump_tree_ssa_stats (FILE *file) | |
1671 | { | |
bf190e8d | 1672 | if (var_infos.is_created ()) |
38635499 | 1673 | { |
b4e209fd RG |
1674 | fprintf (file, "\nHash table statistics:\n"); |
1675 | fprintf (file, " var_infos: "); | |
1676 | htab_statistics (file, var_infos); | |
1677 | fprintf (file, "\n"); | |
38635499 | 1678 | } |
6de9cd9a DN |
1679 | } |
1680 | ||
1681 | ||
1682 | /* Dump SSA statistics on stderr. */ | |
1683 | ||
24e47c76 | 1684 | DEBUG_FUNCTION void |
6de9cd9a DN |
1685 | debug_tree_ssa_stats (void) |
1686 | { | |
1687 | dump_tree_ssa_stats (stderr); | |
1688 | } | |
1689 | ||
1690 | ||
b4e209fd | 1691 | /* Callback for htab_traverse to dump the VAR_INFOS hash table. */ |
6de9cd9a | 1692 | |
bf190e8d LC |
1693 | int |
1694 | debug_var_infos_r (var_info_d **slot, FILE *file) | |
7256233c | 1695 | { |
bf190e8d | 1696 | struct var_info_d *info = *slot; |
b8698a0f | 1697 | |
38635499 | 1698 | fprintf (file, "VAR: "); |
8812aab1 RG |
1699 | print_generic_expr (file, info->var, dump_flags); |
1700 | bitmap_print (file, info->info.def_blocks.def_blocks, | |
1701 | ", DEF_BLOCKS: { ", "}"); | |
1702 | bitmap_print (file, info->info.def_blocks.livein_blocks, | |
1703 | ", LIVEIN_BLOCKS: { ", "}"); | |
1704 | bitmap_print (file, info->info.def_blocks.phi_blocks, | |
1705 | ", PHI_BLOCKS: { ", "}\n"); | |
6de9cd9a | 1706 | |
7256233c DN |
1707 | return 1; |
1708 | } | |
6de9cd9a | 1709 | |
6de9cd9a | 1710 | |
b4e209fd | 1711 | /* Dump the VAR_INFOS hash table on FILE. */ |
38635499 DN |
1712 | |
1713 | void | |
b4e209fd | 1714 | dump_var_infos (FILE *file) |
38635499 DN |
1715 | { |
1716 | fprintf (file, "\n\nDefinition and live-in blocks:\n\n"); | |
bf190e8d LC |
1717 | if (var_infos.is_created ()) |
1718 | var_infos.traverse <FILE *, debug_var_infos_r> (file); | |
38635499 DN |
1719 | } |
1720 | ||
1721 | ||
b4e209fd | 1722 | /* Dump the VAR_INFOS hash table on stderr. */ |
6de9cd9a | 1723 | |
24e47c76 | 1724 | DEBUG_FUNCTION void |
b4e209fd | 1725 | debug_var_infos (void) |
7256233c | 1726 | { |
b4e209fd | 1727 | dump_var_infos (stderr); |
7256233c | 1728 | } |
6de9cd9a | 1729 | |
5f240ec4 | 1730 | |
0bca51f0 | 1731 | /* Register NEW_NAME to be the new reaching definition for OLD_NAME. */ |
6de9cd9a | 1732 | |
0bca51f0 DN |
1733 | static inline void |
1734 | register_new_update_single (tree new_name, tree old_name) | |
1735 | { | |
8812aab1 RG |
1736 | common_info_p info = get_common_info (old_name); |
1737 | tree currdef = info->current_def; | |
5f240ec4 | 1738 | |
38635499 | 1739 | /* Push the current reaching definition into BLOCK_DEFS_STACK. |
0bca51f0 DN |
1740 | This stack is later used by the dominator tree callbacks to |
1741 | restore the reaching definitions for all the variables | |
1742 | defined in the block after a recursive visit to all its | |
1743 | immediately dominated blocks. */ | |
9771b263 DN |
1744 | block_defs_stack.reserve (2); |
1745 | block_defs_stack.quick_push (currdef); | |
1746 | block_defs_stack.quick_push (old_name); | |
5f240ec4 | 1747 | |
0bca51f0 DN |
1748 | /* Set the current reaching definition for OLD_NAME to be |
1749 | NEW_NAME. */ | |
8812aab1 | 1750 | info->current_def = new_name; |
0bca51f0 | 1751 | } |
7256233c | 1752 | |
6de9cd9a | 1753 | |
0bca51f0 DN |
1754 | /* Register NEW_NAME to be the new reaching definition for all the |
1755 | names in OLD_NAMES. Used by the incremental SSA update routines to | |
1756 | replace old SSA names with new ones. */ | |
7256233c | 1757 | |
0bca51f0 DN |
1758 | static inline void |
1759 | register_new_update_set (tree new_name, bitmap old_names) | |
1760 | { | |
1761 | bitmap_iterator bi; | |
1762 | unsigned i; | |
7256233c | 1763 | |
0bca51f0 DN |
1764 | EXECUTE_IF_SET_IN_BITMAP (old_names, 0, i, bi) |
1765 | register_new_update_single (new_name, ssa_name (i)); | |
6de9cd9a DN |
1766 | } |
1767 | ||
7256233c | 1768 | |
0bca51f0 | 1769 | |
84d65814 DN |
1770 | /* If the operand pointed to by USE_P is a name in OLD_SSA_NAMES or |
1771 | it is a symbol marked for renaming, replace it with USE_P's current | |
1772 | reaching definition. */ | |
1773 | ||
1774 | static inline void | |
1775 | maybe_replace_use (use_operand_p use_p) | |
1776 | { | |
1777 | tree rdef = NULL_TREE; | |
1778 | tree use = USE_FROM_PTR (use_p); | |
1779 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); | |
1780 | ||
13714310 | 1781 | if (marked_for_renaming (sym)) |
84d65814 DN |
1782 | rdef = get_reaching_def (sym); |
1783 | else if (is_old_name (use)) | |
1784 | rdef = get_reaching_def (use); | |
1785 | ||
1786 | if (rdef && rdef != use) | |
1787 | SET_USE (use_p, rdef); | |
1788 | } | |
1789 | ||
1790 | ||
b5b8b0ac AO |
1791 | /* Same as maybe_replace_use, but without introducing default stmts, |
1792 | returning false to indicate a need to do so. */ | |
1793 | ||
1794 | static inline bool | |
1795 | maybe_replace_use_in_debug_stmt (use_operand_p use_p) | |
1796 | { | |
1797 | tree rdef = NULL_TREE; | |
1798 | tree use = USE_FROM_PTR (use_p); | |
1799 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); | |
1800 | ||
13714310 | 1801 | if (marked_for_renaming (sym)) |
8812aab1 | 1802 | rdef = get_var_info (sym)->info.current_def; |
b5b8b0ac AO |
1803 | else if (is_old_name (use)) |
1804 | { | |
8812aab1 | 1805 | rdef = get_ssa_name_ann (use)->info.current_def; |
b5b8b0ac AO |
1806 | /* We can't assume that, if there's no current definition, the |
1807 | default one should be used. It could be the case that we've | |
1808 | rearranged blocks so that the earlier definition no longer | |
1809 | dominates the use. */ | |
1810 | if (!rdef && SSA_NAME_IS_DEFAULT_DEF (use)) | |
1811 | rdef = use; | |
1812 | } | |
1813 | else | |
1814 | rdef = use; | |
1815 | ||
1816 | if (rdef && rdef != use) | |
1817 | SET_USE (use_p, rdef); | |
1818 | ||
1819 | return rdef != NULL_TREE; | |
1820 | } | |
1821 | ||
1822 | ||
84d65814 DN |
1823 | /* If the operand pointed to by DEF_P is an SSA name in NEW_SSA_NAMES |
1824 | or OLD_SSA_NAMES, or if it is a symbol marked for renaming, | |
1825 | register it as the current definition for the names replaced by | |
1826 | DEF_P. */ | |
1827 | ||
1828 | static inline void | |
3a56edc7 AO |
1829 | maybe_register_def (def_operand_p def_p, gimple stmt, |
1830 | gimple_stmt_iterator gsi) | |
84d65814 DN |
1831 | { |
1832 | tree def = DEF_FROM_PTR (def_p); | |
1833 | tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def); | |
1834 | ||
38635499 DN |
1835 | /* If DEF is a naked symbol that needs renaming, create a new |
1836 | name for it. */ | |
13714310 | 1837 | if (marked_for_renaming (sym)) |
84d65814 DN |
1838 | { |
1839 | if (DECL_P (def)) | |
1840 | { | |
3a56edc7 AO |
1841 | tree tracked_var; |
1842 | ||
84d65814 DN |
1843 | def = make_ssa_name (def, stmt); |
1844 | SET_DEF (def_p, def); | |
3a56edc7 AO |
1845 | |
1846 | tracked_var = target_for_debug_bind (sym); | |
1847 | if (tracked_var) | |
1848 | { | |
1849 | gimple note = gimple_build_debug_bind (tracked_var, def, stmt); | |
c47987fa JJ |
1850 | /* If stmt ends the bb, insert the debug stmt on the single |
1851 | non-EH edge from the stmt. */ | |
1852 | if (gsi_one_before_end_p (gsi) && stmt_ends_bb_p (stmt)) | |
1853 | { | |
1854 | basic_block bb = gsi_bb (gsi); | |
1855 | edge_iterator ei; | |
1856 | edge e, ef = NULL; | |
1857 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1858 | if (!(e->flags & EDGE_EH)) | |
1859 | { | |
4ad14919 | 1860 | gcc_checking_assert (!ef); |
c47987fa JJ |
1861 | ef = e; |
1862 | } | |
23d5ed5d AO |
1863 | /* If there are other predecessors to ef->dest, then |
1864 | there must be PHI nodes for the modified | |
1865 | variable, and therefore there will be debug bind | |
1866 | stmts after the PHI nodes. The debug bind notes | |
1867 | we'd insert would force the creation of a new | |
1868 | block (diverging codegen) and be redundant with | |
1869 | the post-PHI bind stmts, so don't add them. | |
1870 | ||
1871 | As for the exit edge, there wouldn't be redundant | |
1872 | bind stmts, but there wouldn't be a PC to bind | |
1873 | them to either, so avoid diverging the CFG. */ | |
1874 | if (ef && single_pred_p (ef->dest) | |
1875 | && ef->dest != EXIT_BLOCK_PTR) | |
1876 | { | |
1877 | /* If there were PHI nodes in the node, we'd | |
1878 | have to make sure the value we're binding | |
1879 | doesn't need rewriting. But there shouldn't | |
1880 | be PHI nodes in a single-predecessor block, | |
1881 | so we just add the note. */ | |
1882 | gsi_insert_on_edge_immediate (ef, note); | |
1883 | } | |
c47987fa JJ |
1884 | } |
1885 | else | |
1886 | gsi_insert_after (&gsi, note, GSI_SAME_STMT); | |
3a56edc7 | 1887 | } |
84d65814 DN |
1888 | } |
1889 | ||
1890 | register_new_update_single (def, sym); | |
1891 | } | |
1892 | else | |
1893 | { | |
1894 | /* If DEF is a new name, register it as a new definition | |
1895 | for all the names replaced by DEF. */ | |
1896 | if (is_new_name (def)) | |
1897 | register_new_update_set (def, names_replaced_by (def)); | |
1898 | ||
1899 | /* If DEF is an old name, register DEF as a new | |
1900 | definition for itself. */ | |
1901 | if (is_old_name (def)) | |
1902 | register_new_update_single (def, def); | |
1903 | } | |
1904 | } | |
1905 | ||
1906 | ||
0bca51f0 DN |
1907 | /* Update every variable used in the statement pointed-to by SI. The |
1908 | statement is assumed to be in SSA form already. Names in | |
1909 | OLD_SSA_NAMES used by SI will be updated to their current reaching | |
1910 | definition. Names in OLD_SSA_NAMES or NEW_SSA_NAMES defined by SI | |
1911 | will be registered as a new definition for their corresponding name | |
1912 | in OLD_SSA_NAMES. */ | |
1913 | ||
1914 | static void | |
3a56edc7 | 1915 | rewrite_update_stmt (gimple stmt, gimple_stmt_iterator gsi) |
0bca51f0 | 1916 | { |
0bca51f0 DN |
1917 | use_operand_p use_p; |
1918 | def_operand_p def_p; | |
1919 | ssa_op_iter iter; | |
1920 | ||
0bca51f0 | 1921 | /* Only update marked statements. */ |
726a989a | 1922 | if (!rewrite_uses_p (stmt) && !register_defs_p (stmt)) |
0bca51f0 DN |
1923 | return; |
1924 | ||
1925 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1926 | { | |
1927 | fprintf (dump_file, "Updating SSA information for statement "); | |
726a989a | 1928 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); |
0bca51f0 DN |
1929 | } |
1930 | ||
1931 | /* Rewrite USES included in OLD_SSA_NAMES and USES whose underlying | |
1932 | symbol is marked for renaming. */ | |
726a989a | 1933 | if (rewrite_uses_p (stmt)) |
b5b8b0ac AO |
1934 | { |
1935 | if (is_gimple_debug (stmt)) | |
1936 | { | |
1937 | bool failed = false; | |
1938 | ||
1939 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) | |
1940 | if (!maybe_replace_use_in_debug_stmt (use_p)) | |
1941 | { | |
1942 | failed = true; | |
1943 | break; | |
1944 | } | |
1945 | ||
1946 | if (failed) | |
1947 | { | |
1948 | /* DOM sometimes threads jumps in such a way that a | |
1949 | debug stmt ends up referencing a SSA variable that no | |
1950 | longer dominates the debug stmt, but such that all | |
1951 | incoming definitions refer to the same definition in | |
1952 | an earlier dominator. We could try to recover that | |
1953 | definition somehow, but this will have to do for now. | |
1954 | ||
1955 | Introducing a default definition, which is what | |
1956 | maybe_replace_use() would do in such cases, may | |
1957 | modify code generation, for the otherwise-unused | |
1958 | default definition would never go away, modifying SSA | |
1959 | version numbers all over. */ | |
1960 | gimple_debug_bind_reset_value (stmt); | |
1961 | update_stmt (stmt); | |
1962 | } | |
1963 | } | |
1964 | else | |
1965 | { | |
1966 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) | |
1967 | maybe_replace_use (use_p); | |
1968 | } | |
1969 | } | |
0bca51f0 DN |
1970 | |
1971 | /* Register definitions of names in NEW_SSA_NAMES and OLD_SSA_NAMES. | |
1972 | Also register definitions for names whose underlying symbol is | |
1973 | marked for renaming. */ | |
726a989a | 1974 | if (register_defs_p (stmt)) |
5006671f | 1975 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_ALL_DEFS) |
3a56edc7 | 1976 | maybe_register_def (def_p, stmt, gsi); |
0bca51f0 DN |
1977 | } |
1978 | ||
1979 | ||
1980 | /* Visit all the successor blocks of BB looking for PHI nodes. For | |
1981 | every PHI node found, check if any of its arguments is in | |
1982 | OLD_SSA_NAMES. If so, and if the argument has a current reaching | |
1983 | definition, replace it. */ | |
1984 | ||
1985 | static void | |
ccf5c864 | 1986 | rewrite_update_phi_arguments (basic_block bb) |
0bca51f0 DN |
1987 | { |
1988 | edge e; | |
1989 | edge_iterator ei; | |
2ce79879 | 1990 | unsigned i; |
0bca51f0 DN |
1991 | |
1992 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1993 | { | |
726a989a RB |
1994 | gimple phi; |
1995 | gimple_vec phis; | |
0bca51f0 | 1996 | |
2ce79879 ZD |
1997 | if (!bitmap_bit_p (blocks_with_phis_to_rewrite, e->dest->index)) |
1998 | continue; | |
b8698a0f | 1999 | |
9771b263 DN |
2000 | phis = phis_to_rewrite[e->dest->index]; |
2001 | FOR_EACH_VEC_ELT (phis, i, phi) | |
0bca51f0 | 2002 | { |
f5045c96 | 2003 | tree arg, lhs_sym, reaching_def = NULL; |
0bca51f0 DN |
2004 | use_operand_p arg_p; |
2005 | ||
4ad14919 | 2006 | gcc_checking_assert (rewrite_uses_p (phi)); |
0bca51f0 DN |
2007 | |
2008 | arg_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e); | |
2009 | arg = USE_FROM_PTR (arg_p); | |
2010 | ||
2011 | if (arg && !DECL_P (arg) && TREE_CODE (arg) != SSA_NAME) | |
2012 | continue; | |
2013 | ||
726a989a | 2014 | lhs_sym = SSA_NAME_VAR (gimple_phi_result (phi)); |
38635499 | 2015 | |
0bca51f0 DN |
2016 | if (arg == NULL_TREE) |
2017 | { | |
2018 | /* When updating a PHI node for a recently introduced | |
2019 | symbol we may find NULL arguments. That's why we | |
2020 | take the symbol from the LHS of the PHI node. */ | |
f5045c96 AM |
2021 | reaching_def = get_reaching_def (lhs_sym); |
2022 | ||
0bca51f0 DN |
2023 | } |
2024 | else | |
2025 | { | |
2026 | tree sym = DECL_P (arg) ? arg : SSA_NAME_VAR (arg); | |
2027 | ||
13714310 | 2028 | if (marked_for_renaming (sym)) |
f5045c96 | 2029 | reaching_def = get_reaching_def (sym); |
0bca51f0 | 2030 | else if (is_old_name (arg)) |
f5045c96 AM |
2031 | reaching_def = get_reaching_def (arg); |
2032 | } | |
2033 | ||
2034 | /* Update the argument if there is a reaching def. */ | |
2035 | if (reaching_def) | |
2036 | { | |
f5045c96 AM |
2037 | source_location locus; |
2038 | int arg_i = PHI_ARG_INDEX_FROM_USE (arg_p); | |
2039 | ||
2040 | SET_USE (arg_p, reaching_def); | |
f5045c96 | 2041 | |
ffc5b2bb RB |
2042 | /* Virtual operands do not need a location. */ |
2043 | if (virtual_operand_p (reaching_def)) | |
2044 | locus = UNKNOWN_LOCATION; | |
f5045c96 | 2045 | else |
ffc5b2bb RB |
2046 | { |
2047 | gimple stmt = SSA_NAME_DEF_STMT (reaching_def); | |
2048 | ||
2049 | /* Single element PHI nodes behave like copies, so get the | |
2050 | location from the phi argument. */ | |
2051 | if (gimple_code (stmt) == GIMPLE_PHI | |
2052 | && gimple_phi_num_args (stmt) == 1) | |
2053 | locus = gimple_phi_arg_location (stmt, 0); | |
2054 | else | |
2055 | locus = gimple_location (stmt); | |
2056 | } | |
f5045c96 AM |
2057 | |
2058 | gimple_phi_arg_set_location (phi, arg_i, locus); | |
0bca51f0 DN |
2059 | } |
2060 | ||
f5045c96 | 2061 | |
0bca51f0 DN |
2062 | if (e->flags & EDGE_ABNORMAL) |
2063 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (arg_p)) = 1; | |
2064 | } | |
2065 | } | |
2066 | } | |
2067 | ||
2068 | ||
ccf5c864 PB |
2069 | /* Initialization of block data structures for the incremental SSA |
2070 | update pass. Create a block local stack of reaching definitions | |
2071 | for new SSA names produced in this block (BLOCK_DEFS). Register | |
2072 | new definitions for every PHI node in the block. */ | |
2073 | ||
2074 | static void | |
2075 | rewrite_update_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
2076 | basic_block bb) | |
2077 | { | |
ccf5c864 PB |
2078 | bool is_abnormal_phi; |
2079 | gimple_stmt_iterator gsi; | |
2080 | ||
2081 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
427f99e2 | 2082 | fprintf (dump_file, "Registering new PHI nodes in block #%d\n", |
ccf5c864 PB |
2083 | bb->index); |
2084 | ||
2085 | /* Mark the unwind point for this block. */ | |
9771b263 | 2086 | block_defs_stack.safe_push (NULL_TREE); |
ccf5c864 PB |
2087 | |
2088 | if (!bitmap_bit_p (blocks_to_update, bb->index)) | |
2089 | return; | |
2090 | ||
2091 | /* Mark the LHS if any of the arguments flows through an abnormal | |
2092 | edge. */ | |
31ff2426 | 2093 | is_abnormal_phi = bb_has_abnormal_pred (bb); |
ccf5c864 PB |
2094 | |
2095 | /* If any of the PHI nodes is a replacement for a name in | |
2096 | OLD_SSA_NAMES or it's one of the names in NEW_SSA_NAMES, then | |
2097 | register it as a new definition for its corresponding name. Also | |
2098 | register definitions for names whose underlying symbols are | |
2099 | marked for renaming. */ | |
2100 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2101 | { | |
2102 | tree lhs, lhs_sym; | |
2103 | gimple phi = gsi_stmt (gsi); | |
2104 | ||
2105 | if (!register_defs_p (phi)) | |
2106 | continue; | |
b8698a0f | 2107 | |
ccf5c864 PB |
2108 | lhs = gimple_phi_result (phi); |
2109 | lhs_sym = SSA_NAME_VAR (lhs); | |
2110 | ||
13714310 | 2111 | if (marked_for_renaming (lhs_sym)) |
ccf5c864 PB |
2112 | register_new_update_single (lhs, lhs_sym); |
2113 | else | |
2114 | { | |
2115 | ||
2116 | /* If LHS is a new name, register a new definition for all | |
2117 | the names replaced by LHS. */ | |
2118 | if (is_new_name (lhs)) | |
2119 | register_new_update_set (lhs, names_replaced_by (lhs)); | |
b8698a0f | 2120 | |
ccf5c864 PB |
2121 | /* If LHS is an OLD name, register it as a new definition |
2122 | for itself. */ | |
2123 | if (is_old_name (lhs)) | |
2124 | register_new_update_single (lhs, lhs); | |
2125 | } | |
2126 | ||
2127 | if (is_abnormal_phi) | |
2128 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs) = 1; | |
2129 | } | |
2130 | ||
2131 | /* Step 2. Rewrite every variable used in each statement in the block. */ | |
d7c028c0 | 2132 | if (bitmap_bit_p (interesting_blocks, bb->index)) |
3a56edc7 | 2133 | { |
4ad14919 | 2134 | gcc_checking_assert (bitmap_bit_p (blocks_to_update, bb->index)); |
ccf5c864 | 2135 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
3a56edc7 AO |
2136 | rewrite_update_stmt (gsi_stmt (gsi), gsi); |
2137 | } | |
ccf5c864 PB |
2138 | |
2139 | /* Step 3. Update PHI nodes. */ | |
2140 | rewrite_update_phi_arguments (bb); | |
2141 | } | |
2142 | ||
2143 | /* Called after visiting block BB. Unwind BLOCK_DEFS_STACK to restore | |
2144 | the current reaching definition of every name re-written in BB to | |
2145 | the original reaching definition before visiting BB. This | |
2146 | unwinding must be done in the opposite order to what is done in | |
2147 | register_new_update_set. */ | |
2148 | ||
2149 | static void | |
2150 | rewrite_update_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, | |
2151 | basic_block bb ATTRIBUTE_UNUSED) | |
2152 | { | |
9771b263 | 2153 | while (block_defs_stack.length () > 0) |
ccf5c864 | 2154 | { |
9771b263 | 2155 | tree var = block_defs_stack.pop (); |
ccf5c864 | 2156 | tree saved_def; |
b8698a0f | 2157 | |
ccf5c864 PB |
2158 | /* NULL indicates the unwind stop point for this block (see |
2159 | rewrite_update_enter_block). */ | |
2160 | if (var == NULL) | |
2161 | return; | |
2162 | ||
9771b263 | 2163 | saved_def = block_defs_stack.pop (); |
8812aab1 | 2164 | get_common_info (var)->current_def = saved_def; |
ccf5c864 PB |
2165 | } |
2166 | } | |
2167 | ||
2168 | ||
0bca51f0 | 2169 | /* Rewrite the actual blocks, statements, and PHI arguments, to be in SSA |
b8698a0f | 2170 | form. |
0bca51f0 DN |
2171 | |
2172 | ENTRY indicates the block where to start. Every block dominated by | |
2173 | ENTRY will be rewritten. | |
2174 | ||
2175 | WHAT indicates what actions will be taken by the renamer (see enum | |
2176 | rewrite_mode). | |
2177 | ||
2178 | BLOCKS are the set of interesting blocks for the dominator walker | |
2179 | to process. If this set is NULL, then all the nodes dominated | |
2180 | by ENTRY are walked. Otherwise, blocks dominated by ENTRY that | |
2181 | are not present in BLOCKS are ignored. */ | |
2182 | ||
2183 | static void | |
ccf5c864 | 2184 | rewrite_blocks (basic_block entry, enum rewrite_mode what) |
0bca51f0 DN |
2185 | { |
2186 | struct dom_walk_data walk_data; | |
b8698a0f | 2187 | |
0bca51f0 DN |
2188 | /* Rewrite all the basic blocks in the program. */ |
2189 | timevar_push (TV_TREE_SSA_REWRITE_BLOCKS); | |
2190 | ||
2191 | /* Setup callbacks for the generic dominator tree walker. */ | |
2192 | memset (&walk_data, 0, sizeof (walk_data)); | |
2193 | ||
2194 | walk_data.dom_direction = CDI_DOMINATORS; | |
0bca51f0 DN |
2195 | |
2196 | if (what == REWRITE_ALL) | |
ccf5c864 PB |
2197 | { |
2198 | walk_data.before_dom_children = rewrite_enter_block; | |
2199 | walk_data.after_dom_children = rewrite_leave_block; | |
2200 | } | |
0bca51f0 | 2201 | else if (what == REWRITE_UPDATE) |
ccf5c864 PB |
2202 | { |
2203 | walk_data.before_dom_children = rewrite_update_enter_block; | |
2204 | walk_data.after_dom_children = rewrite_update_leave_block; | |
2205 | } | |
0bca51f0 DN |
2206 | else |
2207 | gcc_unreachable (); | |
2208 | ||
9771b263 | 2209 | block_defs_stack.create (10); |
0bca51f0 DN |
2210 | |
2211 | /* Initialize the dominator walker. */ | |
2212 | init_walk_dominator_tree (&walk_data); | |
2213 | ||
2214 | /* Recursively walk the dominator tree rewriting each statement in | |
2215 | each basic block. */ | |
2216 | walk_dominator_tree (&walk_data, entry); | |
2217 | ||
2218 | /* Finalize the dominator walker. */ | |
2219 | fini_walk_dominator_tree (&walk_data); | |
2220 | ||
2221 | /* Debugging dumps. */ | |
2222 | if (dump_file && (dump_flags & TDF_STATS)) | |
2223 | { | |
2224 | dump_dfa_stats (dump_file); | |
bf190e8d | 2225 | if (var_infos.is_created ()) |
0bca51f0 DN |
2226 | dump_tree_ssa_stats (dump_file); |
2227 | } | |
b8698a0f | 2228 | |
9771b263 | 2229 | block_defs_stack.release (); |
0bca51f0 DN |
2230 | |
2231 | timevar_pop (TV_TREE_SSA_REWRITE_BLOCKS); | |
2232 | } | |
2233 | ||
2234 | ||
ccf5c864 PB |
2235 | /* Block processing routine for mark_def_sites. Clear the KILLS bitmap |
2236 | at the start of each block, and call mark_def_sites for each statement. */ | |
6de9cd9a | 2237 | |
5f240ec4 | 2238 | static void |
ccf5c864 | 2239 | mark_def_sites_block (struct dom_walk_data *walk_data, basic_block bb) |
5f240ec4 | 2240 | { |
38635499 | 2241 | struct mark_def_sites_global_data *gd; |
ccf5c864 PB |
2242 | bitmap kills; |
2243 | gimple_stmt_iterator gsi; | |
2244 | ||
38635499 | 2245 | gd = (struct mark_def_sites_global_data *) walk_data->global_data; |
ccf5c864 PB |
2246 | kills = gd->kills; |
2247 | ||
2248 | bitmap_clear (kills); | |
2249 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2250 | mark_def_sites (bb, gsi_stmt (gsi), kills); | |
7256233c | 2251 | } |
5f240ec4 | 2252 | |
5f240ec4 | 2253 | |
0bca51f0 DN |
2254 | /* Mark the definition site blocks for each variable, so that we know |
2255 | where the variable is actually live. | |
2256 | ||
ccf5c864 PB |
2257 | The INTERESTING_BLOCKS global will be filled in with all the blocks |
2258 | that should be processed by the renamer. It is assumed that the | |
2259 | caller has already initialized and zeroed it. */ | |
5f240ec4 | 2260 | |
0bca51f0 | 2261 | static void |
ccf5c864 | 2262 | mark_def_site_blocks (void) |
7256233c | 2263 | { |
7256233c DN |
2264 | struct dom_walk_data walk_data; |
2265 | struct mark_def_sites_global_data mark_def_sites_global_data; | |
5f240ec4 | 2266 | |
7256233c DN |
2267 | /* Setup callbacks for the generic dominator tree walker to find and |
2268 | mark definition sites. */ | |
7256233c DN |
2269 | walk_data.dom_direction = CDI_DOMINATORS; |
2270 | walk_data.initialize_block_local_data = NULL; | |
ccf5c864 PB |
2271 | walk_data.before_dom_children = mark_def_sites_block; |
2272 | walk_data.after_dom_children = NULL; | |
5f240ec4 | 2273 | |
7256233c DN |
2274 | /* Notice that this bitmap is indexed using variable UIDs, so it must be |
2275 | large enough to accommodate all the variables referenced in the | |
2276 | function, not just the ones we are renaming. */ | |
2277 | mark_def_sites_global_data.kills = BITMAP_ALLOC (NULL); | |
2278 | walk_data.global_data = &mark_def_sites_global_data; | |
6de9cd9a | 2279 | |
7256233c DN |
2280 | /* We do not have any local data. */ |
2281 | walk_data.block_local_data_size = 0; | |
2282 | ||
2283 | /* Initialize the dominator walker. */ | |
2284 | init_walk_dominator_tree (&walk_data); | |
2285 | ||
2286 | /* Recursively walk the dominator tree. */ | |
2287 | walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR); | |
2288 | ||
2289 | /* Finalize the dominator walker. */ | |
2290 | fini_walk_dominator_tree (&walk_data); | |
2291 | ||
2292 | /* We no longer need this bitmap, clear and free it. */ | |
2293 | BITMAP_FREE (mark_def_sites_global_data.kills); | |
6de9cd9a DN |
2294 | } |
2295 | ||
6de9cd9a | 2296 | |
38635499 DN |
2297 | /* Initialize internal data needed during renaming. */ |
2298 | ||
2299 | static void | |
2300 | init_ssa_renamer (void) | |
2301 | { | |
38635499 DN |
2302 | cfun->gimple_df->in_ssa_p = false; |
2303 | ||
2304 | /* Allocate memory for the DEF_BLOCKS hash table. */ | |
bf190e8d LC |
2305 | gcc_assert (!var_infos.is_created ()); |
2306 | var_infos.create (vec_safe_length (cfun->local_decls)); | |
38635499 | 2307 | |
b4e209fd | 2308 | bitmap_obstack_initialize (&update_ssa_obstack); |
38635499 DN |
2309 | } |
2310 | ||
2311 | ||
2312 | /* Deallocate internal data structures used by the renamer. */ | |
2313 | ||
2314 | static void | |
2315 | fini_ssa_renamer (void) | |
2316 | { | |
bf190e8d LC |
2317 | if (var_infos.is_created ()) |
2318 | var_infos.dispose (); | |
38635499 | 2319 | |
b4e209fd RG |
2320 | bitmap_obstack_release (&update_ssa_obstack); |
2321 | ||
13714310 RG |
2322 | cfun->gimple_df->ssa_renaming_needed = 0; |
2323 | cfun->gimple_df->rename_vops = 0; | |
38635499 DN |
2324 | cfun->gimple_df->in_ssa_p = true; |
2325 | } | |
2326 | ||
7256233c | 2327 | /* Main entry point into the SSA builder. The renaming process |
0bca51f0 | 2328 | proceeds in four main phases: |
6de9cd9a | 2329 | |
0bca51f0 DN |
2330 | 1- Compute dominance frontier and immediate dominators, needed to |
2331 | insert PHI nodes and rename the function in dominator tree | |
2332 | order. | |
6de9cd9a | 2333 | |
0bca51f0 | 2334 | 2- Find and mark all the blocks that define variables |
7256233c | 2335 | (mark_def_site_blocks). |
6de9cd9a | 2336 | |
0bca51f0 | 2337 | 3- Insert PHI nodes at dominance frontiers (insert_phi_nodes). |
6de9cd9a | 2338 | |
0bca51f0 | 2339 | 4- Rename all the blocks (rewrite_blocks) and statements in the program. |
6de9cd9a | 2340 | |
77bfa778 | 2341 | Steps 3 and 4 are done using the dominator tree walker |
0bca51f0 | 2342 | (walk_dominator_tree). */ |
7256233c | 2343 | |
c2924966 | 2344 | static unsigned int |
0bca51f0 | 2345 | rewrite_into_ssa (void) |
6de9cd9a | 2346 | { |
0fc555fb | 2347 | bitmap_head *dfs; |
7256233c | 2348 | basic_block bb; |
70b5e7dc | 2349 | unsigned i; |
b8698a0f | 2350 | |
0bca51f0 | 2351 | /* Initialize operand data structures. */ |
3828719a | 2352 | init_ssa_operands (cfun); |
6de9cd9a | 2353 | |
38635499 DN |
2354 | /* Initialize internal data needed by the renamer. */ |
2355 | init_ssa_renamer (); | |
2356 | ||
0bca51f0 DN |
2357 | /* Initialize the set of interesting blocks. The callback |
2358 | mark_def_sites will add to this set those blocks that the renamer | |
2359 | should process. */ | |
2360 | interesting_blocks = sbitmap_alloc (last_basic_block); | |
f61e445a | 2361 | bitmap_clear (interesting_blocks); |
6de9cd9a | 2362 | |
af5d3a18 | 2363 | /* Initialize dominance frontier. */ |
0fc555fb | 2364 | dfs = XNEWVEC (bitmap_head, last_basic_block); |
7256233c | 2365 | FOR_EACH_BB (bb) |
0fc555fb | 2366 | bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack); |
6de9cd9a | 2367 | |
0bca51f0 DN |
2368 | /* 1- Compute dominance frontiers. */ |
2369 | calculate_dominance_info (CDI_DOMINATORS); | |
7256233c | 2370 | compute_dominance_frontiers (dfs); |
6de9cd9a | 2371 | |
0bca51f0 | 2372 | /* 2- Find and mark definition sites. */ |
ccf5c864 | 2373 | mark_def_site_blocks (); |
0bca51f0 DN |
2374 | |
2375 | /* 3- Insert PHI nodes at dominance frontiers of definition blocks. */ | |
84d65814 | 2376 | insert_phi_nodes (dfs); |
6de9cd9a | 2377 | |
0bca51f0 | 2378 | /* 4- Rename all the blocks. */ |
ccf5c864 | 2379 | rewrite_blocks (ENTRY_BLOCK_PTR, REWRITE_ALL); |
6de9cd9a | 2380 | |
7256233c DN |
2381 | /* Free allocated memory. */ |
2382 | FOR_EACH_BB (bb) | |
0fc555fb | 2383 | bitmap_clear (&dfs[bb->index]); |
7256233c | 2384 | free (dfs); |
6de9cd9a | 2385 | |
b5dcb2b9 JL |
2386 | sbitmap_free (interesting_blocks); |
2387 | ||
38635499 DN |
2388 | fini_ssa_renamer (); |
2389 | ||
70b5e7dc RG |
2390 | /* Try to get rid of all gimplifier generated temporaries by making |
2391 | its SSA names anonymous. This way we can garbage collect them | |
2392 | all after removing unused locals which we do in our TODO. */ | |
2393 | for (i = 1; i < num_ssa_names; ++i) | |
2394 | { | |
2395 | tree decl, name = ssa_name (i); | |
2396 | if (!name | |
2397 | || SSA_NAME_IS_DEFAULT_DEF (name)) | |
2398 | continue; | |
2399 | decl = SSA_NAME_VAR (name); | |
2400 | if (decl | |
2401 | && TREE_CODE (decl) == VAR_DECL | |
2402 | && !VAR_DECL_IS_VIRTUAL_OPERAND (decl) | |
2403 | && DECL_ARTIFICIAL (decl) | |
2404 | && DECL_IGNORED_P (decl) | |
2405 | && !DECL_NAME (decl)) | |
2406 | SET_SSA_NAME_VAR_OR_IDENTIFIER (name, NULL_TREE); | |
2407 | } | |
2408 | ||
c2924966 | 2409 | return 0; |
6de9cd9a DN |
2410 | } |
2411 | ||
2412 | ||
27a4cd48 DM |
2413 | namespace { |
2414 | ||
2415 | const pass_data pass_data_build_ssa = | |
2416 | { | |
2417 | GIMPLE_PASS, /* type */ | |
2418 | "ssa", /* name */ | |
2419 | OPTGROUP_NONE, /* optinfo_flags */ | |
2420 | false, /* has_gate */ | |
2421 | true, /* has_execute */ | |
2422 | TV_TREE_SSA_OTHER, /* tv_id */ | |
2423 | PROP_cfg, /* properties_required */ | |
2424 | PROP_ssa, /* properties_provided */ | |
2425 | 0, /* properties_destroyed */ | |
2426 | 0, /* todo_flags_start */ | |
2427 | ( TODO_verify_ssa | TODO_remove_unused_locals ), /* todo_flags_finish */ | |
7256233c | 2428 | }; |
6de9cd9a | 2429 | |
27a4cd48 DM |
2430 | class pass_build_ssa : public gimple_opt_pass |
2431 | { | |
2432 | public: | |
2433 | pass_build_ssa(gcc::context *ctxt) | |
2434 | : gimple_opt_pass(pass_data_build_ssa, ctxt) | |
2435 | {} | |
2436 | ||
2437 | /* opt_pass methods: */ | |
2438 | unsigned int execute () { return rewrite_into_ssa (); } | |
2439 | ||
2440 | }; // class pass_build_ssa | |
2441 | ||
2442 | } // anon namespace | |
2443 | ||
2444 | gimple_opt_pass * | |
2445 | make_pass_build_ssa (gcc::context *ctxt) | |
2446 | { | |
2447 | return new pass_build_ssa (ctxt); | |
2448 | } | |
2449 | ||
6de9cd9a | 2450 | |
0bca51f0 DN |
2451 | /* Mark the definition of VAR at STMT and BB as interesting for the |
2452 | renamer. BLOCKS is the set of blocks that need updating. */ | |
6de9cd9a | 2453 | |
0bca51f0 | 2454 | static void |
726a989a | 2455 | mark_def_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p) |
6de9cd9a | 2456 | { |
4ad14919 | 2457 | gcc_checking_assert (bitmap_bit_p (blocks_to_update, bb->index)); |
726a989a | 2458 | set_register_defs (stmt, true); |
0bca51f0 DN |
2459 | |
2460 | if (insert_phi_p) | |
2461 | { | |
726a989a | 2462 | bool is_phi_p = gimple_code (stmt) == GIMPLE_PHI; |
0bca51f0 | 2463 | |
0bca51f0 DN |
2464 | set_def_block (var, bb, is_phi_p); |
2465 | ||
2466 | /* If VAR is an SSA name in NEW_SSA_NAMES, this is a definition | |
2467 | site for both itself and all the old names replaced by it. */ | |
2468 | if (TREE_CODE (var) == SSA_NAME && is_new_name (var)) | |
2469 | { | |
2470 | bitmap_iterator bi; | |
2471 | unsigned i; | |
2472 | bitmap set = names_replaced_by (var); | |
2473 | if (set) | |
2474 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) | |
2475 | set_def_block (ssa_name (i), bb, is_phi_p); | |
2476 | } | |
2477 | } | |
2478 | } | |
2479 | ||
2480 | ||
2481 | /* Mark the use of VAR at STMT and BB as interesting for the | |
2482 | renamer. INSERT_PHI_P is true if we are going to insert new PHI | |
95dd3097 | 2483 | nodes. */ |
0bca51f0 DN |
2484 | |
2485 | static inline void | |
726a989a | 2486 | mark_use_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p) |
0bca51f0 | 2487 | { |
726a989a | 2488 | basic_block def_bb = gimple_bb (stmt); |
2ce79879 | 2489 | |
95dd3097 ZD |
2490 | mark_block_for_update (def_bb); |
2491 | mark_block_for_update (bb); | |
2492 | ||
726a989a | 2493 | if (gimple_code (stmt) == GIMPLE_PHI) |
2ce79879 ZD |
2494 | mark_phi_for_rewrite (def_bb, stmt); |
2495 | else | |
b5b8b0ac AO |
2496 | { |
2497 | set_rewrite_uses (stmt, true); | |
2498 | ||
2499 | if (is_gimple_debug (stmt)) | |
2500 | return; | |
2501 | } | |
0bca51f0 DN |
2502 | |
2503 | /* If VAR has not been defined in BB, then it is live-on-entry | |
2504 | to BB. Note that we cannot just use the block holding VAR's | |
2505 | definition because if VAR is one of the names in OLD_SSA_NAMES, | |
2506 | it will have several definitions (itself and all the names that | |
2507 | replace it). */ | |
2508 | if (insert_phi_p) | |
2509 | { | |
8812aab1 | 2510 | struct def_blocks_d *db_p = get_def_blocks_for (get_common_info (var)); |
0bca51f0 DN |
2511 | if (!bitmap_bit_p (db_p->def_blocks, bb->index)) |
2512 | set_livein_block (var, bb); | |
2513 | } | |
2514 | } | |
2515 | ||
2516 | ||
0bca51f0 | 2517 | /* Do a dominator walk starting at BB processing statements that |
13714310 | 2518 | reference symbols in SSA operands. This is very similar to |
84d65814 | 2519 | mark_def_sites, but the scan handles statements whose operands may |
95dd3097 | 2520 | already be SSA names. |
0bca51f0 | 2521 | |
84d65814 DN |
2522 | If INSERT_PHI_P is true, mark those uses as live in the |
2523 | corresponding block. This is later used by the PHI placement | |
38635499 DN |
2524 | algorithm to make PHI pruning decisions. |
2525 | ||
2526 | FIXME. Most of this would be unnecessary if we could associate a | |
2527 | symbol to all the SSA names that reference it. But that | |
2528 | sounds like it would be expensive to maintain. Still, it | |
2529 | would be interesting to see if it makes better sense to do | |
2530 | that. */ | |
0bca51f0 DN |
2531 | |
2532 | static void | |
95dd3097 | 2533 | prepare_block_for_update (basic_block bb, bool insert_phi_p) |
0bca51f0 DN |
2534 | { |
2535 | basic_block son; | |
726a989a | 2536 | gimple_stmt_iterator si; |
f074ff6c ZD |
2537 | edge e; |
2538 | edge_iterator ei; | |
0bca51f0 | 2539 | |
95dd3097 ZD |
2540 | mark_block_for_update (bb); |
2541 | ||
0bca51f0 | 2542 | /* Process PHI nodes marking interesting those that define or use |
84d65814 | 2543 | the symbols that we are interested in. */ |
726a989a | 2544 | for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si)) |
0bca51f0 | 2545 | { |
726a989a RB |
2546 | gimple phi = gsi_stmt (si); |
2547 | tree lhs_sym, lhs = gimple_phi_result (phi); | |
0bca51f0 | 2548 | |
13714310 | 2549 | if (TREE_CODE (lhs) == SSA_NAME |
a471762f RG |
2550 | && (! virtual_operand_p (lhs) |
2551 | || ! cfun->gimple_df->rename_vops)) | |
f074ff6c | 2552 | continue; |
726a989a | 2553 | |
a471762f | 2554 | lhs_sym = DECL_P (lhs) ? lhs : SSA_NAME_VAR (lhs); |
13714310 | 2555 | mark_for_renaming (lhs_sym); |
f074ff6c ZD |
2556 | mark_def_interesting (lhs_sym, phi, bb, insert_phi_p); |
2557 | ||
2558 | /* Mark the uses in phi nodes as interesting. It would be more correct | |
2559 | to process the arguments of the phi nodes of the successor edges of | |
2560 | BB at the end of prepare_block_for_update, however, that turns out | |
2561 | to be significantly more expensive. Doing it here is conservatively | |
2562 | correct -- it may only cause us to believe a value to be live in a | |
2563 | block that also contains its definition, and thus insert a few more | |
2564 | phi nodes for it. */ | |
2565 | FOR_EACH_EDGE (e, ei, bb->preds) | |
726a989a | 2566 | mark_use_interesting (lhs_sym, phi, e->src, insert_phi_p); |
0bca51f0 DN |
2567 | } |
2568 | ||
2569 | /* Process the statements. */ | |
726a989a | 2570 | for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) |
0bca51f0 | 2571 | { |
726a989a | 2572 | gimple stmt; |
0bca51f0 DN |
2573 | ssa_op_iter i; |
2574 | use_operand_p use_p; | |
2575 | def_operand_p def_p; | |
b8698a0f | 2576 | |
726a989a | 2577 | stmt = gsi_stmt (si); |
0bca51f0 | 2578 | |
13714310 RG |
2579 | if (cfun->gimple_df->rename_vops |
2580 | && gimple_vuse (stmt)) | |
0bca51f0 | 2581 | { |
13714310 | 2582 | tree use = gimple_vuse (stmt); |
0bca51f0 | 2583 | tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use); |
13714310 RG |
2584 | mark_for_renaming (sym); |
2585 | mark_use_interesting (sym, stmt, bb, insert_phi_p); | |
0bca51f0 DN |
2586 | } |
2587 | ||
13714310 | 2588 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, i, SSA_OP_USE) |
0bca51f0 | 2589 | { |
13714310 RG |
2590 | tree use = USE_FROM_PTR (use_p); |
2591 | if (!DECL_P (use)) | |
2592 | continue; | |
2593 | mark_for_renaming (use); | |
2594 | mark_use_interesting (use, stmt, bb, insert_phi_p); | |
2595 | } | |
2596 | ||
2597 | if (cfun->gimple_df->rename_vops | |
2598 | && gimple_vdef (stmt)) | |
2599 | { | |
2600 | tree def = gimple_vdef (stmt); | |
0bca51f0 | 2601 | tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def); |
13714310 RG |
2602 | mark_for_renaming (sym); |
2603 | mark_def_interesting (sym, stmt, bb, insert_phi_p); | |
2604 | } | |
2605 | ||
2606 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, i, SSA_OP_DEF) | |
2607 | { | |
2608 | tree def = DEF_FROM_PTR (def_p); | |
2609 | if (!DECL_P (def)) | |
2610 | continue; | |
2611 | mark_for_renaming (def); | |
2612 | mark_def_interesting (def, stmt, bb, insert_phi_p); | |
0bca51f0 DN |
2613 | } |
2614 | } | |
2615 | ||
2616 | /* Now visit all the blocks dominated by BB. */ | |
84d65814 | 2617 | for (son = first_dom_son (CDI_DOMINATORS, bb); |
38635499 DN |
2618 | son; |
2619 | son = next_dom_son (CDI_DOMINATORS, son)) | |
95dd3097 | 2620 | prepare_block_for_update (son, insert_phi_p); |
84d65814 DN |
2621 | } |
2622 | ||
2623 | ||
2624 | /* Helper for prepare_names_to_update. Mark all the use sites for | |
2625 | NAME as interesting. BLOCKS and INSERT_PHI_P are as in | |
2626 | prepare_names_to_update. */ | |
2627 | ||
2628 | static void | |
95dd3097 | 2629 | prepare_use_sites_for (tree name, bool insert_phi_p) |
84d65814 DN |
2630 | { |
2631 | use_operand_p use_p; | |
2632 | imm_use_iterator iter; | |
2633 | ||
2634 | FOR_EACH_IMM_USE_FAST (use_p, iter, name) | |
2635 | { | |
726a989a RB |
2636 | gimple stmt = USE_STMT (use_p); |
2637 | basic_block bb = gimple_bb (stmt); | |
84d65814 | 2638 | |
726a989a | 2639 | if (gimple_code (stmt) == GIMPLE_PHI) |
84d65814 | 2640 | { |
f074ff6c | 2641 | int ix = PHI_ARG_INDEX_FROM_USE (use_p); |
726a989a | 2642 | edge e = gimple_phi_arg_edge (stmt, ix); |
f074ff6c | 2643 | mark_use_interesting (name, stmt, e->src, insert_phi_p); |
84d65814 DN |
2644 | } |
2645 | else | |
2646 | { | |
2647 | /* For regular statements, mark this as an interesting use | |
2648 | for NAME. */ | |
95dd3097 | 2649 | mark_use_interesting (name, stmt, bb, insert_phi_p); |
84d65814 DN |
2650 | } |
2651 | } | |
0bca51f0 DN |
2652 | } |
2653 | ||
2654 | ||
84d65814 DN |
2655 | /* Helper for prepare_names_to_update. Mark the definition site for |
2656 | NAME as interesting. BLOCKS and INSERT_PHI_P are as in | |
2657 | prepare_names_to_update. */ | |
0bca51f0 DN |
2658 | |
2659 | static void | |
95dd3097 | 2660 | prepare_def_site_for (tree name, bool insert_phi_p) |
0bca51f0 | 2661 | { |
726a989a | 2662 | gimple stmt; |
0bca51f0 DN |
2663 | basic_block bb; |
2664 | ||
4ad14919 RG |
2665 | gcc_checking_assert (names_to_release == NULL |
2666 | || !bitmap_bit_p (names_to_release, | |
2667 | SSA_NAME_VERSION (name))); | |
0bca51f0 DN |
2668 | |
2669 | stmt = SSA_NAME_DEF_STMT (name); | |
726a989a | 2670 | bb = gimple_bb (stmt); |
0bca51f0 DN |
2671 | if (bb) |
2672 | { | |
4ad14919 | 2673 | gcc_checking_assert (bb->index < last_basic_block); |
95dd3097 ZD |
2674 | mark_block_for_update (bb); |
2675 | mark_def_interesting (name, stmt, bb, insert_phi_p); | |
0bca51f0 DN |
2676 | } |
2677 | } | |
2678 | ||
2679 | ||
84d65814 | 2680 | /* Mark definition and use sites of names in NEW_SSA_NAMES and |
95dd3097 ZD |
2681 | OLD_SSA_NAMES. INSERT_PHI_P is true if the caller wants to insert |
2682 | PHI nodes for newly created names. */ | |
0bca51f0 DN |
2683 | |
2684 | static void | |
95dd3097 | 2685 | prepare_names_to_update (bool insert_phi_p) |
0bca51f0 | 2686 | { |
dfea6c85 | 2687 | unsigned i = 0; |
0bca51f0 | 2688 | bitmap_iterator bi; |
b6e7e9af | 2689 | sbitmap_iterator sbi; |
0bca51f0 DN |
2690 | |
2691 | /* If a name N from NEW_SSA_NAMES is also marked to be released, | |
2692 | remove it from NEW_SSA_NAMES so that we don't try to visit its | |
2693 | defining basic block (which most likely doesn't exist). Notice | |
2694 | that we cannot do the same with names in OLD_SSA_NAMES because we | |
2695 | want to replace existing instances. */ | |
2696 | if (names_to_release) | |
2697 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) | |
d7c028c0 | 2698 | bitmap_clear_bit (new_ssa_names, i); |
0bca51f0 | 2699 | |
84d65814 DN |
2700 | /* First process names in NEW_SSA_NAMES. Otherwise, uses of old |
2701 | names may be considered to be live-in on blocks that contain | |
2702 | definitions for their replacements. */ | |
d4ac4ce2 | 2703 | EXECUTE_IF_SET_IN_BITMAP (new_ssa_names, 0, i, sbi) |
95dd3097 | 2704 | prepare_def_site_for (ssa_name (i), insert_phi_p); |
84d65814 | 2705 | |
0bca51f0 DN |
2706 | /* If an old name is in NAMES_TO_RELEASE, we cannot remove it from |
2707 | OLD_SSA_NAMES, but we have to ignore its definition site. */ | |
d4ac4ce2 | 2708 | EXECUTE_IF_SET_IN_BITMAP (old_ssa_names, 0, i, sbi) |
84d65814 DN |
2709 | { |
2710 | if (names_to_release == NULL || !bitmap_bit_p (names_to_release, i)) | |
95dd3097 ZD |
2711 | prepare_def_site_for (ssa_name (i), insert_phi_p); |
2712 | prepare_use_sites_for (ssa_name (i), insert_phi_p); | |
b6e7e9af | 2713 | } |
0bca51f0 DN |
2714 | } |
2715 | ||
2716 | ||
2717 | /* Dump all the names replaced by NAME to FILE. */ | |
2718 | ||
2719 | void | |
2720 | dump_names_replaced_by (FILE *file, tree name) | |
2721 | { | |
2722 | unsigned i; | |
2723 | bitmap old_set; | |
2724 | bitmap_iterator bi; | |
2725 | ||
2726 | print_generic_expr (file, name, 0); | |
2727 | fprintf (file, " -> { "); | |
2728 | ||
2729 | old_set = names_replaced_by (name); | |
2730 | EXECUTE_IF_SET_IN_BITMAP (old_set, 0, i, bi) | |
2731 | { | |
2732 | print_generic_expr (file, ssa_name (i), 0); | |
2733 | fprintf (file, " "); | |
2734 | } | |
2735 | ||
2736 | fprintf (file, "}\n"); | |
2737 | } | |
2738 | ||
2739 | ||
2740 | /* Dump all the names replaced by NAME to stderr. */ | |
2741 | ||
24e47c76 | 2742 | DEBUG_FUNCTION void |
0bca51f0 DN |
2743 | debug_names_replaced_by (tree name) |
2744 | { | |
2745 | dump_names_replaced_by (stderr, name); | |
2746 | } | |
2747 | ||
2748 | ||
84d65814 | 2749 | /* Dump SSA update information to FILE. */ |
0bca51f0 DN |
2750 | |
2751 | void | |
84d65814 | 2752 | dump_update_ssa (FILE *file) |
0bca51f0 | 2753 | { |
dfea6c85 | 2754 | unsigned i = 0; |
0bca51f0 DN |
2755 | bitmap_iterator bi; |
2756 | ||
5006671f | 2757 | if (!need_ssa_update_p (cfun)) |
0bca51f0 DN |
2758 | return; |
2759 | ||
f61e445a | 2760 | if (new_ssa_names && bitmap_first_set_bit (new_ssa_names) >= 0) |
0bca51f0 | 2761 | { |
b6e7e9af KH |
2762 | sbitmap_iterator sbi; |
2763 | ||
0bca51f0 DN |
2764 | fprintf (file, "\nSSA replacement table\n"); |
2765 | fprintf (file, "N_i -> { O_1 ... O_j } means that N_i replaces " | |
2766 | "O_1, ..., O_j\n\n"); | |
2767 | ||
d4ac4ce2 | 2768 | EXECUTE_IF_SET_IN_BITMAP (new_ssa_names, 0, i, sbi) |
b6e7e9af | 2769 | dump_names_replaced_by (file, ssa_name (i)); |
0bca51f0 DN |
2770 | } |
2771 | ||
13714310 | 2772 | if (symbols_to_rename_set && !bitmap_empty_p (symbols_to_rename_set)) |
0bca51f0 | 2773 | { |
427f99e2 | 2774 | fprintf (file, "\nSymbols to be put in SSA form\n"); |
13714310 | 2775 | dump_decl_set (file, symbols_to_rename_set); |
5006671f | 2776 | fprintf (file, "\n"); |
0bca51f0 DN |
2777 | } |
2778 | ||
0bca51f0 DN |
2779 | if (names_to_release && !bitmap_empty_p (names_to_release)) |
2780 | { | |
427f99e2 | 2781 | fprintf (file, "\nSSA names to release after updating the SSA web\n\n"); |
0bca51f0 DN |
2782 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) |
2783 | { | |
2784 | print_generic_expr (file, ssa_name (i), 0); | |
2785 | fprintf (file, " "); | |
2786 | } | |
427f99e2 | 2787 | fprintf (file, "\n"); |
0bca51f0 | 2788 | } |
0bca51f0 DN |
2789 | } |
2790 | ||
2791 | ||
84d65814 | 2792 | /* Dump SSA update information to stderr. */ |
0bca51f0 | 2793 | |
24e47c76 | 2794 | DEBUG_FUNCTION void |
84d65814 | 2795 | debug_update_ssa (void) |
0bca51f0 | 2796 | { |
84d65814 | 2797 | dump_update_ssa (stderr); |
0bca51f0 DN |
2798 | } |
2799 | ||
2800 | ||
2801 | /* Initialize data structures used for incremental SSA updates. */ | |
2802 | ||
2803 | static void | |
5006671f | 2804 | init_update_ssa (struct function *fn) |
0bca51f0 | 2805 | { |
84d65814 | 2806 | /* Reserve more space than the current number of names. The calls to |
0bca51f0 DN |
2807 | add_new_name_mapping are typically done after creating new SSA |
2808 | names, so we'll need to reallocate these arrays. */ | |
2809 | old_ssa_names = sbitmap_alloc (num_ssa_names + NAME_SETS_GROWTH_FACTOR); | |
f61e445a | 2810 | bitmap_clear (old_ssa_names); |
0bca51f0 DN |
2811 | |
2812 | new_ssa_names = sbitmap_alloc (num_ssa_names + NAME_SETS_GROWTH_FACTOR); | |
f61e445a | 2813 | bitmap_clear (new_ssa_names); |
0bca51f0 | 2814 | |
891f2df6 RG |
2815 | bitmap_obstack_initialize (&update_ssa_obstack); |
2816 | ||
0bca51f0 | 2817 | names_to_release = NULL; |
5006671f | 2818 | update_ssa_initialized_fn = fn; |
0bca51f0 DN |
2819 | } |
2820 | ||
2821 | ||
2822 | /* Deallocate data structures used for incremental SSA updates. */ | |
2823 | ||
84d65814 | 2824 | void |
0bca51f0 DN |
2825 | delete_update_ssa (void) |
2826 | { | |
2827 | unsigned i; | |
2828 | bitmap_iterator bi; | |
2829 | ||
2830 | sbitmap_free (old_ssa_names); | |
2831 | old_ssa_names = NULL; | |
2832 | ||
2833 | sbitmap_free (new_ssa_names); | |
2834 | new_ssa_names = NULL; | |
2835 | ||
13714310 RG |
2836 | BITMAP_FREE (symbols_to_rename_set); |
2837 | symbols_to_rename_set = NULL; | |
9771b263 | 2838 | symbols_to_rename.release (); |
0bca51f0 DN |
2839 | |
2840 | if (names_to_release) | |
2841 | { | |
2842 | EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi) | |
2843 | release_ssa_name (ssa_name (i)); | |
2844 | BITMAP_FREE (names_to_release); | |
2845 | } | |
2846 | ||
95dd3097 | 2847 | clear_ssa_name_info (); |
38635499 DN |
2848 | |
2849 | fini_ssa_renamer (); | |
2850 | ||
2851 | if (blocks_with_phis_to_rewrite) | |
2852 | EXECUTE_IF_SET_IN_BITMAP (blocks_with_phis_to_rewrite, 0, i, bi) | |
2853 | { | |
9771b263 DN |
2854 | gimple_vec phis = phis_to_rewrite[i]; |
2855 | phis.release (); | |
2856 | phis_to_rewrite[i].create (0); | |
38635499 DN |
2857 | } |
2858 | ||
2859 | BITMAP_FREE (blocks_with_phis_to_rewrite); | |
2860 | BITMAP_FREE (blocks_to_update); | |
891f2df6 | 2861 | |
5006671f | 2862 | update_ssa_initialized_fn = NULL; |
0bca51f0 DN |
2863 | } |
2864 | ||
2865 | ||
2866 | /* Create a new name for OLD_NAME in statement STMT and replace the | |
45db3141 RG |
2867 | operand pointed to by DEF_P with the newly created name. If DEF_P |
2868 | is NULL then STMT should be a GIMPLE assignment. | |
2869 | Return the new name and register the replacement mapping <NEW, OLD> in | |
0bca51f0 DN |
2870 | update_ssa's tables. */ |
2871 | ||
2872 | tree | |
726a989a | 2873 | create_new_def_for (tree old_name, gimple stmt, def_operand_p def) |
0bca51f0 | 2874 | { |
45db3141 | 2875 | tree new_name; |
0bca51f0 | 2876 | |
45db3141 RG |
2877 | timevar_push (TV_TREE_SSA_INCREMENTAL); |
2878 | ||
2879 | if (!update_ssa_initialized_fn) | |
2880 | init_update_ssa (cfun); | |
2881 | ||
2882 | gcc_assert (update_ssa_initialized_fn == cfun); | |
2883 | ||
2884 | new_name = duplicate_ssa_name (old_name, stmt); | |
2885 | if (def) | |
2886 | SET_DEF (def, new_name); | |
2887 | else | |
2888 | gimple_assign_set_lhs (stmt, new_name); | |
0bca51f0 | 2889 | |
726a989a | 2890 | if (gimple_code (stmt) == GIMPLE_PHI) |
0bca51f0 | 2891 | { |
726a989a | 2892 | basic_block bb = gimple_bb (stmt); |
0bca51f0 DN |
2893 | |
2894 | /* If needed, mark NEW_NAME as occurring in an abnormal PHI node. */ | |
31ff2426 | 2895 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_name) = bb_has_abnormal_pred (bb); |
0bca51f0 DN |
2896 | } |
2897 | ||
45db3141 | 2898 | add_new_name_mapping (new_name, old_name); |
0bca51f0 DN |
2899 | |
2900 | /* For the benefit of passes that will be updating the SSA form on | |
2901 | their own, set the current reaching definition of OLD_NAME to be | |
2902 | NEW_NAME. */ | |
8812aab1 | 2903 | get_ssa_name_ann (old_name)->info.current_def = new_name; |
0bca51f0 | 2904 | |
45db3141 | 2905 | timevar_pop (TV_TREE_SSA_INCREMENTAL); |
0bca51f0 | 2906 | |
45db3141 | 2907 | return new_name; |
0bca51f0 DN |
2908 | } |
2909 | ||
2910 | ||
525174a2 | 2911 | /* Mark virtual operands of FN for renaming by update_ssa. */ |
0bca51f0 DN |
2912 | |
2913 | void | |
525174a2 | 2914 | mark_virtual_operands_for_renaming (struct function *fn) |
0bca51f0 | 2915 | { |
525174a2 RG |
2916 | fn->gimple_df->ssa_renaming_needed = 1; |
2917 | fn->gimple_df->rename_vops = 1; | |
0bca51f0 DN |
2918 | } |
2919 | ||
2920 | ||
5006671f RG |
2921 | /* Return true if there is any work to be done by update_ssa |
2922 | for function FN. */ | |
0bca51f0 DN |
2923 | |
2924 | bool | |
5006671f | 2925 | need_ssa_update_p (struct function *fn) |
0bca51f0 | 2926 | { |
5006671f RG |
2927 | gcc_assert (fn != NULL); |
2928 | return (update_ssa_initialized_fn == fn | |
13714310 | 2929 | || (fn->gimple_df && fn->gimple_df->ssa_renaming_needed)); |
0bca51f0 DN |
2930 | } |
2931 | ||
0bca51f0 DN |
2932 | /* Return true if name N has been registered in the replacement table. */ |
2933 | ||
2934 | bool | |
726a989a | 2935 | name_registered_for_update_p (tree n ATTRIBUTE_UNUSED) |
0bca51f0 | 2936 | { |
5006671f | 2937 | if (!update_ssa_initialized_fn) |
0bca51f0 DN |
2938 | return false; |
2939 | ||
5006671f RG |
2940 | gcc_assert (update_ssa_initialized_fn == cfun); |
2941 | ||
2942 | return is_new_name (n) || is_old_name (n); | |
0bca51f0 DN |
2943 | } |
2944 | ||
2945 | ||
0bca51f0 DN |
2946 | /* Mark NAME to be released after update_ssa has finished. */ |
2947 | ||
2948 | void | |
2949 | release_ssa_name_after_update_ssa (tree name) | |
2950 | { | |
5006671f | 2951 | gcc_assert (cfun && update_ssa_initialized_fn == cfun); |
0bca51f0 DN |
2952 | |
2953 | if (names_to_release == NULL) | |
2954 | names_to_release = BITMAP_ALLOC (NULL); | |
2955 | ||
2956 | bitmap_set_bit (names_to_release, SSA_NAME_VERSION (name)); | |
2957 | } | |
2958 | ||
2959 | ||
2960 | /* Insert new PHI nodes to replace VAR. DFS contains dominance | |
2961 | frontier information. BLOCKS is the set of blocks to be updated. | |
2962 | ||
2963 | This is slightly different than the regular PHI insertion | |
2964 | algorithm. The value of UPDATE_FLAGS controls how PHI nodes for | |
2965 | real names (i.e., GIMPLE registers) are inserted: | |
b8698a0f | 2966 | |
0bca51f0 DN |
2967 | - If UPDATE_FLAGS == TODO_update_ssa, we are only interested in PHI |
2968 | nodes inside the region affected by the block that defines VAR | |
2969 | and the blocks that define all its replacements. All these | |
84d65814 | 2970 | definition blocks are stored in DEF_BLOCKS[VAR]->DEF_BLOCKS. |
0bca51f0 DN |
2971 | |
2972 | First, we compute the entry point to the region (ENTRY). This is | |
2973 | given by the nearest common dominator to all the definition | |
2974 | blocks. When computing the iterated dominance frontier (IDF), any | |
2975 | block not strictly dominated by ENTRY is ignored. | |
2976 | ||
2977 | We then call the standard PHI insertion algorithm with the pruned | |
2978 | IDF. | |
2979 | ||
2980 | - If UPDATE_FLAGS == TODO_update_ssa_full_phi, the IDF for real | |
2981 | names is not pruned. PHI nodes are inserted at every IDF block. */ | |
2982 | ||
2983 | static void | |
0fc555fb | 2984 | insert_updated_phi_nodes_for (tree var, bitmap_head *dfs, bitmap blocks, |
0bca51f0 DN |
2985 | unsigned update_flags) |
2986 | { | |
2987 | basic_block entry; | |
2988 | struct def_blocks_d *db; | |
2989 | bitmap idf, pruned_idf; | |
2990 | bitmap_iterator bi; | |
2991 | unsigned i; | |
2992 | ||
0bca51f0 | 2993 | if (TREE_CODE (var) == SSA_NAME) |
77a74ed7 | 2994 | gcc_checking_assert (is_old_name (var)); |
0bca51f0 | 2995 | else |
13714310 | 2996 | gcc_checking_assert (marked_for_renaming (var)); |
0bca51f0 DN |
2997 | |
2998 | /* Get all the definition sites for VAR. */ | |
2999 | db = find_def_blocks_for (var); | |
3000 | ||
3001 | /* No need to do anything if there were no definitions to VAR. */ | |
3002 | if (db == NULL || bitmap_empty_p (db->def_blocks)) | |
3003 | return; | |
3004 | ||
3005 | /* Compute the initial iterated dominance frontier. */ | |
38635499 | 3006 | idf = compute_idf (db->def_blocks, dfs); |
0bca51f0 DN |
3007 | pruned_idf = BITMAP_ALLOC (NULL); |
3008 | ||
3009 | if (TREE_CODE (var) == SSA_NAME) | |
3010 | { | |
3011 | if (update_flags == TODO_update_ssa) | |
3012 | { | |
3013 | /* If doing regular SSA updates for GIMPLE registers, we are | |
3014 | only interested in IDF blocks dominated by the nearest | |
3015 | common dominator of all the definition blocks. */ | |
3016 | entry = nearest_common_dominator_for_set (CDI_DOMINATORS, | |
3017 | db->def_blocks); | |
0bca51f0 DN |
3018 | if (entry != ENTRY_BLOCK_PTR) |
3019 | EXECUTE_IF_SET_IN_BITMAP (idf, 0, i, bi) | |
3020 | if (BASIC_BLOCK (i) != entry | |
3021 | && dominated_by_p (CDI_DOMINATORS, BASIC_BLOCK (i), entry)) | |
3022 | bitmap_set_bit (pruned_idf, i); | |
3023 | } | |
3024 | else | |
3025 | { | |
3026 | /* Otherwise, do not prune the IDF for VAR. */ | |
4ad14919 | 3027 | gcc_checking_assert (update_flags == TODO_update_ssa_full_phi); |
0bca51f0 DN |
3028 | bitmap_copy (pruned_idf, idf); |
3029 | } | |
3030 | } | |
3031 | else | |
3032 | { | |
3033 | /* Otherwise, VAR is a symbol that needs to be put into SSA form | |
3034 | for the first time, so we need to compute the full IDF for | |
3035 | it. */ | |
3036 | bitmap_copy (pruned_idf, idf); | |
0bca51f0 DN |
3037 | } |
3038 | ||
3039 | if (!bitmap_empty_p (pruned_idf)) | |
3040 | { | |
3041 | /* Make sure that PRUNED_IDF blocks and all their feeding blocks | |
3042 | are included in the region to be updated. The feeding blocks | |
3043 | are important to guarantee that the PHI arguments are renamed | |
3044 | properly. */ | |
38635499 DN |
3045 | |
3046 | /* FIXME, this is not needed if we are updating symbols. We are | |
3047 | already starting at the ENTRY block anyway. */ | |
0bca51f0 DN |
3048 | bitmap_ior_into (blocks, pruned_idf); |
3049 | EXECUTE_IF_SET_IN_BITMAP (pruned_idf, 0, i, bi) | |
3050 | { | |
3051 | edge e; | |
3052 | edge_iterator ei; | |
3053 | basic_block bb = BASIC_BLOCK (i); | |
3054 | ||
3055 | FOR_EACH_EDGE (e, ei, bb->preds) | |
3056 | if (e->src->index >= 0) | |
3057 | bitmap_set_bit (blocks, e->src->index); | |
3058 | } | |
3059 | ||
3060 | insert_phi_nodes_for (var, pruned_idf, true); | |
3061 | } | |
3062 | ||
3063 | BITMAP_FREE (pruned_idf); | |
3064 | BITMAP_FREE (idf); | |
3065 | } | |
3066 | ||
fa5556de RB |
3067 | /* Sort symbols_to_rename after their DECL_UID. */ |
3068 | ||
3069 | static int | |
3070 | insert_updated_phi_nodes_compare_uids (const void *a, const void *b) | |
3071 | { | |
3072 | const_tree syma = *(const const_tree *)a; | |
3073 | const_tree symb = *(const const_tree *)b; | |
3074 | if (DECL_UID (syma) == DECL_UID (symb)) | |
3075 | return 0; | |
3076 | return DECL_UID (syma) < DECL_UID (symb) ? -1 : 1; | |
3077 | } | |
0bca51f0 DN |
3078 | |
3079 | /* Given a set of newly created SSA names (NEW_SSA_NAMES) and a set of | |
3080 | existing SSA names (OLD_SSA_NAMES), update the SSA form so that: | |
3081 | ||
3082 | 1- The names in OLD_SSA_NAMES dominated by the definitions of | |
3083 | NEW_SSA_NAMES are all re-written to be reached by the | |
3084 | appropriate definition from NEW_SSA_NAMES. | |
3085 | ||
3086 | 2- If needed, new PHI nodes are added to the iterated dominance | |
3087 | frontier of the blocks where each of NEW_SSA_NAMES are defined. | |
3088 | ||
3089 | The mapping between OLD_SSA_NAMES and NEW_SSA_NAMES is setup by | |
45db3141 | 3090 | calling create_new_def_for to create new defs for names that the |
0bca51f0 DN |
3091 | caller wants to replace. |
3092 | ||
45db3141 RG |
3093 | The caller cretaes the new names to be inserted and the names that need |
3094 | to be replaced by calling create_new_def_for for each old definition | |
3095 | to be replaced. Note that the function assumes that the | |
3096 | new defining statement has already been inserted in the IL. | |
0bca51f0 DN |
3097 | |
3098 | For instance, given the following code: | |
3099 | ||
3100 | 1 L0: | |
3101 | 2 x_1 = PHI (0, x_5) | |
3102 | 3 if (x_1 < 10) | |
3103 | 4 if (x_1 > 7) | |
3104 | 5 y_2 = 0 | |
3105 | 6 else | |
3106 | 7 y_3 = x_1 + x_7 | |
3107 | 8 endif | |
3108 | 9 x_5 = x_1 + 1 | |
3109 | 10 goto L0; | |
3110 | 11 endif | |
3111 | ||
3112 | Suppose that we insert new names x_10 and x_11 (lines 4 and 8). | |
3113 | ||
3114 | 1 L0: | |
3115 | 2 x_1 = PHI (0, x_5) | |
3116 | 3 if (x_1 < 10) | |
3117 | 4 x_10 = ... | |
3118 | 5 if (x_1 > 7) | |
3119 | 6 y_2 = 0 | |
3120 | 7 else | |
3121 | 8 x_11 = ... | |
3122 | 9 y_3 = x_1 + x_7 | |
3123 | 10 endif | |
3124 | 11 x_5 = x_1 + 1 | |
3125 | 12 goto L0; | |
3126 | 13 endif | |
3127 | ||
3128 | We want to replace all the uses of x_1 with the new definitions of | |
3129 | x_10 and x_11. Note that the only uses that should be replaced are | |
3130 | those at lines 5, 9 and 11. Also, the use of x_7 at line 9 should | |
3131 | *not* be replaced (this is why we cannot just mark symbol 'x' for | |
3132 | renaming). | |
3133 | ||
3134 | Additionally, we may need to insert a PHI node at line 11 because | |
3135 | that is a merge point for x_10 and x_11. So the use of x_1 at line | |
3136 | 11 will be replaced with the new PHI node. The insertion of PHI | |
3137 | nodes is optional. They are not strictly necessary to preserve the | |
3138 | SSA form, and depending on what the caller inserted, they may not | |
3139 | even be useful for the optimizers. UPDATE_FLAGS controls various | |
3140 | aspects of how update_ssa operates, see the documentation for | |
3141 | TODO_update_ssa*. */ | |
3142 | ||
3143 | void | |
3144 | update_ssa (unsigned update_flags) | |
3145 | { | |
0bca51f0 DN |
3146 | basic_block bb, start_bb; |
3147 | bitmap_iterator bi; | |
dfea6c85 | 3148 | unsigned i = 0; |
0bca51f0 | 3149 | bool insert_phi_p; |
b6e7e9af | 3150 | sbitmap_iterator sbi; |
13714310 | 3151 | tree sym; |
0bca51f0 | 3152 | |
580b2c2e SB |
3153 | /* Only one update flag should be set. */ |
3154 | gcc_assert (update_flags == TODO_update_ssa | |
3155 | || update_flags == TODO_update_ssa_no_phi | |
3156 | || update_flags == TODO_update_ssa_full_phi | |
3157 | || update_flags == TODO_update_ssa_only_virtuals); | |
3158 | ||
5006671f | 3159 | if (!need_ssa_update_p (cfun)) |
0bca51f0 DN |
3160 | return; |
3161 | ||
3162 | timevar_push (TV_TREE_SSA_INCREMENTAL); | |
3163 | ||
427f99e2 MJ |
3164 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3165 | fprintf (dump_file, "\nUpdating SSA:\n"); | |
3166 | ||
5006671f RG |
3167 | if (!update_ssa_initialized_fn) |
3168 | init_update_ssa (cfun); | |
580b2c2e SB |
3169 | else if (update_flags == TODO_update_ssa_only_virtuals) |
3170 | { | |
3171 | /* If we only need to update virtuals, remove all the mappings for | |
3172 | real names before proceeding. The caller is responsible for | |
3173 | having dealt with the name mappings before calling update_ssa. */ | |
f61e445a LC |
3174 | bitmap_clear (old_ssa_names); |
3175 | bitmap_clear (new_ssa_names); | |
580b2c2e SB |
3176 | } |
3177 | ||
5006671f RG |
3178 | gcc_assert (update_ssa_initialized_fn == cfun); |
3179 | ||
2ce79879 | 3180 | blocks_with_phis_to_rewrite = BITMAP_ALLOC (NULL); |
9771b263 DN |
3181 | if (!phis_to_rewrite.exists ()) |
3182 | phis_to_rewrite.create (last_basic_block + 1); | |
95dd3097 | 3183 | blocks_to_update = BITMAP_ALLOC (NULL); |
2ce79879 | 3184 | |
0bca51f0 DN |
3185 | /* Ensure that the dominance information is up-to-date. */ |
3186 | calculate_dominance_info (CDI_DOMINATORS); | |
3187 | ||
84d65814 | 3188 | insert_phi_p = (update_flags != TODO_update_ssa_no_phi); |
0bca51f0 | 3189 | |
84d65814 DN |
3190 | /* If there are names defined in the replacement table, prepare |
3191 | definition and use sites for all the names in NEW_SSA_NAMES and | |
3192 | OLD_SSA_NAMES. */ | |
f61e445a | 3193 | if (bitmap_first_set_bit (new_ssa_names) >= 0) |
84d65814 | 3194 | { |
95dd3097 | 3195 | prepare_names_to_update (insert_phi_p); |
84d65814 DN |
3196 | |
3197 | /* If all the names in NEW_SSA_NAMES had been marked for | |
3198 | removal, and there are no symbols to rename, then there's | |
3199 | nothing else to do. */ | |
f61e445a | 3200 | if (bitmap_first_set_bit (new_ssa_names) < 0 |
13714310 | 3201 | && !cfun->gimple_df->ssa_renaming_needed) |
84d65814 DN |
3202 | goto done; |
3203 | } | |
3204 | ||
3205 | /* Next, determine the block at which to start the renaming process. */ | |
13714310 | 3206 | if (cfun->gimple_df->ssa_renaming_needed) |
84d65814 | 3207 | { |
b4e209fd RG |
3208 | /* If we rename bare symbols initialize the mapping to |
3209 | auxiliar info we need to keep track of. */ | |
bf190e8d | 3210 | var_infos.create (47); |
b4e209fd | 3211 | |
84d65814 DN |
3212 | /* If we have to rename some symbols from scratch, we need to |
3213 | start the process at the root of the CFG. FIXME, it should | |
3214 | be possible to determine the nearest block that had a | |
3215 | definition for each of the symbols that are marked for | |
3216 | updating. For now this seems more work than it's worth. */ | |
3217 | start_bb = ENTRY_BLOCK_PTR; | |
3218 | ||
38635499 | 3219 | /* Traverse the CFG looking for existing definitions and uses of |
13714310 | 3220 | symbols in SSA operands. Mark interesting blocks and |
38635499 DN |
3221 | statements and set local live-in information for the PHI |
3222 | placement heuristics. */ | |
95dd3097 | 3223 | prepare_block_for_update (start_bb, insert_phi_p); |
343c5d46 RG |
3224 | |
3225 | #ifdef ENABLE_CHECKING | |
3226 | for (i = 1; i < num_ssa_names; ++i) | |
3227 | { | |
3228 | tree name = ssa_name (i); | |
3229 | if (!name | |
3230 | || virtual_operand_p (name)) | |
3231 | continue; | |
3232 | ||
3233 | /* For all but virtual operands, which do not have SSA names | |
3234 | with overlapping life ranges, ensure that symbols marked | |
3235 | for renaming do not have existing SSA names associated with | |
3236 | them as we do not re-write them out-of-SSA before going | |
3237 | into SSA for the remaining symbol uses. */ | |
3238 | if (marked_for_renaming (SSA_NAME_VAR (name))) | |
3239 | { | |
3240 | fprintf (stderr, "Existing SSA name for symbol marked for " | |
3241 | "renaming: "); | |
3242 | print_generic_expr (stderr, name, TDF_SLIM); | |
3243 | fprintf (stderr, "\n"); | |
3244 | internal_error ("SSA corruption"); | |
3245 | } | |
3246 | } | |
3247 | #endif | |
0bca51f0 DN |
3248 | } |
3249 | else | |
84d65814 DN |
3250 | { |
3251 | /* Otherwise, the entry block to the region is the nearest | |
3252 | common dominator for the blocks in BLOCKS. */ | |
95dd3097 ZD |
3253 | start_bb = nearest_common_dominator_for_set (CDI_DOMINATORS, |
3254 | blocks_to_update); | |
84d65814 | 3255 | } |
0bca51f0 DN |
3256 | |
3257 | /* If requested, insert PHI nodes at the iterated dominance frontier | |
84d65814 | 3258 | of every block, creating new definitions for names in OLD_SSA_NAMES |
13714310 | 3259 | and for symbols found. */ |
0bca51f0 DN |
3260 | if (insert_phi_p) |
3261 | { | |
0fc555fb | 3262 | bitmap_head *dfs; |
9caf90a8 KH |
3263 | |
3264 | /* If the caller requested PHI nodes to be added, compute | |
3265 | dominance frontiers. */ | |
0fc555fb | 3266 | dfs = XNEWVEC (bitmap_head, last_basic_block); |
9caf90a8 | 3267 | FOR_EACH_BB (bb) |
0fc555fb | 3268 | bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack); |
9caf90a8 KH |
3269 | compute_dominance_frontiers (dfs); |
3270 | ||
f61e445a | 3271 | if (bitmap_first_set_bit (old_ssa_names) >= 0) |
0bca51f0 | 3272 | { |
b6e7e9af KH |
3273 | sbitmap_iterator sbi; |
3274 | ||
84d65814 DN |
3275 | /* insert_update_phi_nodes_for will call add_new_name_mapping |
3276 | when inserting new PHI nodes, so the set OLD_SSA_NAMES | |
3277 | will grow while we are traversing it (but it will not | |
3278 | gain any new members). Copy OLD_SSA_NAMES to a temporary | |
3279 | for traversal. */ | |
5829cc0f | 3280 | sbitmap tmp = sbitmap_alloc (SBITMAP_SIZE (old_ssa_names)); |
f61e445a | 3281 | bitmap_copy (tmp, old_ssa_names); |
d4ac4ce2 | 3282 | EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, sbi) |
95dd3097 | 3283 | insert_updated_phi_nodes_for (ssa_name (i), dfs, blocks_to_update, |
b6e7e9af | 3284 | update_flags); |
0bca51f0 DN |
3285 | sbitmap_free (tmp); |
3286 | } | |
3287 | ||
fa5556de | 3288 | symbols_to_rename.qsort (insert_updated_phi_nodes_compare_uids); |
9771b263 | 3289 | FOR_EACH_VEC_ELT (symbols_to_rename, i, sym) |
13714310 | 3290 | insert_updated_phi_nodes_for (sym, dfs, blocks_to_update, |
38635499 | 3291 | update_flags); |
0bca51f0 | 3292 | |
9caf90a8 | 3293 | FOR_EACH_BB (bb) |
0fc555fb | 3294 | bitmap_clear (&dfs[bb->index]); |
9caf90a8 KH |
3295 | free (dfs); |
3296 | ||
0bca51f0 DN |
3297 | /* Insertion of PHI nodes may have added blocks to the region. |
3298 | We need to re-compute START_BB to include the newly added | |
3299 | blocks. */ | |
3300 | if (start_bb != ENTRY_BLOCK_PTR) | |
95dd3097 ZD |
3301 | start_bb = nearest_common_dominator_for_set (CDI_DOMINATORS, |
3302 | blocks_to_update); | |
0bca51f0 DN |
3303 | } |
3304 | ||
3305 | /* Reset the current definition for name and symbol before renaming | |
3306 | the sub-graph. */ | |
d4ac4ce2 | 3307 | EXECUTE_IF_SET_IN_BITMAP (old_ssa_names, 0, i, sbi) |
8812aab1 | 3308 | get_ssa_name_ann (ssa_name (i))->info.current_def = NULL_TREE; |
0bca51f0 | 3309 | |
9771b263 | 3310 | FOR_EACH_VEC_ELT (symbols_to_rename, i, sym) |
8812aab1 | 3311 | get_var_info (sym)->info.current_def = NULL_TREE; |
0bca51f0 DN |
3312 | |
3313 | /* Now start the renaming process at START_BB. */ | |
ccf5c864 | 3314 | interesting_blocks = sbitmap_alloc (last_basic_block); |
f61e445a | 3315 | bitmap_clear (interesting_blocks); |
95dd3097 | 3316 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
d7c028c0 | 3317 | bitmap_set_bit (interesting_blocks, i); |
0bca51f0 | 3318 | |
ccf5c864 | 3319 | rewrite_blocks (start_bb, REWRITE_UPDATE); |
0bca51f0 | 3320 | |
ccf5c864 | 3321 | sbitmap_free (interesting_blocks); |
0bca51f0 DN |
3322 | |
3323 | /* Debugging dumps. */ | |
3324 | if (dump_file) | |
3325 | { | |
3326 | int c; | |
3327 | unsigned i; | |
3328 | ||
84d65814 | 3329 | dump_update_ssa (dump_file); |
0bca51f0 | 3330 | |
427f99e2 | 3331 | fprintf (dump_file, "Incremental SSA update started at block: %d\n", |
0bca51f0 DN |
3332 | start_bb->index); |
3333 | ||
3334 | c = 0; | |
95dd3097 | 3335 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
0bca51f0 DN |
3336 | c++; |
3337 | fprintf (dump_file, "Number of blocks in CFG: %d\n", last_basic_block); | |
427f99e2 | 3338 | fprintf (dump_file, "Number of blocks to update: %d (%3.0f%%)\n", |
0bca51f0 DN |
3339 | c, PERCENT (c, last_basic_block)); |
3340 | ||
3341 | if (dump_flags & TDF_DETAILS) | |
3342 | { | |
0eb09f31 | 3343 | fprintf (dump_file, "Affected blocks:"); |
95dd3097 | 3344 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi) |
0eb09f31 | 3345 | fprintf (dump_file, " %u", i); |
0bca51f0 DN |
3346 | fprintf (dump_file, "\n"); |
3347 | } | |
3348 | ||
3349 | fprintf (dump_file, "\n\n"); | |
3350 | } | |
3351 | ||
3352 | /* Free allocated memory. */ | |
84d65814 | 3353 | done: |
0bca51f0 DN |
3354 | delete_update_ssa (); |
3355 | ||
3356 | timevar_pop (TV_TREE_SSA_INCREMENTAL); | |
3357 | } |