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6de9cd9a | 1 | /* Convert a program in SSA form into Normal form. |
ad616de1 | 2 | Copyright (C) 2004, 2005 Free Software Foundation, Inc. |
6de9cd9a DN |
3 | Contributed by Andrew Macleod <amacleod@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 | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
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 | |
18 | along with GCC; see the file COPYING. If not, write to | |
19 | the Free Software Foundation, 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
21 | ||
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
25 | #include "tm.h" | |
26 | #include "tree.h" | |
27 | #include "flags.h" | |
28 | #include "rtl.h" | |
29 | #include "tm_p.h" | |
30 | #include "ggc.h" | |
31 | #include "langhooks.h" | |
32 | #include "hard-reg-set.h" | |
33 | #include "basic-block.h" | |
34 | #include "output.h" | |
35 | #include "errors.h" | |
36 | #include "expr.h" | |
37 | #include "function.h" | |
38 | #include "diagnostic.h" | |
39 | #include "bitmap.h" | |
40 | #include "tree-flow.h" | |
eadf906f | 41 | #include "tree-gimple.h" |
6de9cd9a DN |
42 | #include "tree-inline.h" |
43 | #include "varray.h" | |
44 | #include "timevar.h" | |
6de9cd9a DN |
45 | #include "hashtab.h" |
46 | #include "tree-dump.h" | |
47 | #include "tree-ssa-live.h" | |
48 | #include "tree-pass.h" | |
49 | ||
56b043c8 JL |
50 | /* Flags to pass to remove_ssa_form. */ |
51 | ||
52 | #define SSANORM_PERFORM_TER 0x1 | |
53 | #define SSANORM_COMBINE_TEMPS 0x2 | |
dfd9f74c | 54 | #define SSANORM_COALESCE_PARTITIONS 0x4 |
56b043c8 | 55 | |
6de9cd9a DN |
56 | /* Used to hold all the components required to do SSA PHI elimination. |
57 | The node and pred/succ list is a simple linear list of nodes and | |
58 | edges represented as pairs of nodes. | |
59 | ||
60 | The predecessor and successor list: Nodes are entered in pairs, where | |
61 | [0] ->PRED, [1]->SUCC. All the even indexes in the array represent | |
62 | predecessors, all the odd elements are successors. | |
63 | ||
64 | Rationale: | |
65 | When implemented as bitmaps, very large programs SSA->Normal times were | |
66 | being dominated by clearing the interference graph. | |
67 | ||
68 | Typically this list of edges is extremely small since it only includes | |
69 | PHI results and uses from a single edge which have not coalesced with | |
70 | each other. This means that no virtual PHI nodes are included, and | |
71 | empirical evidence suggests that the number of edges rarely exceed | |
72 | 3, and in a bootstrap of GCC, the maximum size encountered was 7. | |
73 | This also limits the number of possible nodes that are involved to | |
74 | rarely more than 6, and in the bootstrap of gcc, the maximum number | |
75 | of nodes encountered was 12. */ | |
76 | ||
77 | typedef struct _elim_graph { | |
78 | /* Size of the elimination vectors. */ | |
79 | int size; | |
80 | ||
81 | /* List of nodes in the elimination graph. */ | |
82 | varray_type nodes; | |
83 | ||
9cf737f8 | 84 | /* The predecessor and successor edge list. */ |
6de9cd9a DN |
85 | varray_type edge_list; |
86 | ||
87 | /* Visited vector. */ | |
88 | sbitmap visited; | |
89 | ||
90 | /* Stack for visited nodes. */ | |
91 | varray_type stack; | |
92 | ||
93 | /* The variable partition map. */ | |
94 | var_map map; | |
95 | ||
96 | /* Edge being eliminated by this graph. */ | |
97 | edge e; | |
98 | ||
99 | /* List of constant copies to emit. These are pushed on in pairs. */ | |
100 | varray_type const_copies; | |
101 | } *elim_graph; | |
102 | ||
103 | ||
104 | /* Local functions. */ | |
105 | static tree create_temp (tree); | |
106 | static void insert_copy_on_edge (edge, tree, tree); | |
107 | static elim_graph new_elim_graph (int); | |
108 | static inline void delete_elim_graph (elim_graph); | |
109 | static inline void clear_elim_graph (elim_graph); | |
110 | static inline int elim_graph_size (elim_graph); | |
111 | static inline void elim_graph_add_node (elim_graph, tree); | |
112 | static inline void elim_graph_add_edge (elim_graph, int, int); | |
113 | static inline int elim_graph_remove_succ_edge (elim_graph, int); | |
114 | ||
115 | static inline void eliminate_name (elim_graph, tree); | |
41f683ef | 116 | static void eliminate_build (elim_graph, basic_block); |
6de9cd9a DN |
117 | static void elim_forward (elim_graph, int); |
118 | static int elim_unvisited_predecessor (elim_graph, int); | |
119 | static void elim_backward (elim_graph, int); | |
120 | static void elim_create (elim_graph, int); | |
41f683ef | 121 | static void eliminate_phi (edge, elim_graph); |
6de9cd9a DN |
122 | static tree_live_info_p coalesce_ssa_name (var_map, int); |
123 | static void assign_vars (var_map); | |
d00ad49b AM |
124 | static bool replace_use_variable (var_map, use_operand_p, tree *); |
125 | static bool replace_def_variable (var_map, def_operand_p, tree *); | |
6de9cd9a DN |
126 | static void eliminate_virtual_phis (void); |
127 | static void coalesce_abnormal_edges (var_map, conflict_graph, root_var_p); | |
128 | static void print_exprs (FILE *, const char *, tree, const char *, tree, | |
129 | const char *); | |
130 | static void print_exprs_edge (FILE *, edge, const char *, tree, const char *, | |
131 | tree); | |
132 | ||
133 | ||
134 | /* Create a temporary variable based on the type of variable T. Use T's name | |
135 | as the prefix. */ | |
136 | ||
137 | static tree | |
138 | create_temp (tree t) | |
139 | { | |
140 | tree tmp; | |
141 | const char *name = NULL; | |
142 | tree type; | |
143 | ||
144 | if (TREE_CODE (t) == SSA_NAME) | |
145 | t = SSA_NAME_VAR (t); | |
1e128c5f GB |
146 | |
147 | gcc_assert (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == PARM_DECL); | |
6de9cd9a DN |
148 | |
149 | type = TREE_TYPE (t); | |
150 | tmp = DECL_NAME (t); | |
151 | if (tmp) | |
152 | name = IDENTIFIER_POINTER (tmp); | |
153 | ||
154 | if (name == NULL) | |
155 | name = "temp"; | |
156 | tmp = create_tmp_var (type, name); | |
ac3bfd86 | 157 | |
dad2a933 RH |
158 | if (DECL_DEBUG_EXPR (t) && DECL_DEBUG_EXPR_IS_FROM (t)) |
159 | { | |
160 | DECL_DEBUG_EXPR (tmp) = DECL_DEBUG_EXPR (t); | |
161 | DECL_DEBUG_EXPR_IS_FROM (tmp) = 1; | |
162 | } | |
ac3bfd86 | 163 | else if (!DECL_IGNORED_P (t)) |
dad2a933 RH |
164 | { |
165 | DECL_DEBUG_EXPR (tmp) = t; | |
166 | DECL_DEBUG_EXPR_IS_FROM (tmp) = 1; | |
167 | } | |
6de9cd9a | 168 | DECL_ARTIFICIAL (tmp) = DECL_ARTIFICIAL (t); |
78e0d62b | 169 | DECL_IGNORED_P (tmp) = DECL_IGNORED_P (t); |
6de9cd9a DN |
170 | add_referenced_tmp_var (tmp); |
171 | ||
172 | /* add_referenced_tmp_var will create the annotation and set up some | |
173 | of the flags in the annotation. However, some flags we need to | |
174 | inherit from our original variable. */ | |
175 | var_ann (tmp)->type_mem_tag = var_ann (t)->type_mem_tag; | |
176 | if (is_call_clobbered (t)) | |
177 | mark_call_clobbered (tmp); | |
178 | ||
179 | return tmp; | |
180 | } | |
181 | ||
182 | ||
183 | /* This helper function fill insert a copy from a constant or variable SRC to | |
184 | variable DEST on edge E. */ | |
185 | ||
186 | static void | |
187 | insert_copy_on_edge (edge e, tree dest, tree src) | |
188 | { | |
189 | tree copy; | |
190 | ||
191 | copy = build (MODIFY_EXPR, TREE_TYPE (dest), dest, src); | |
192 | set_is_used (dest); | |
193 | ||
194 | if (TREE_CODE (src) == ADDR_EXPR) | |
195 | src = TREE_OPERAND (src, 0); | |
196 | if (TREE_CODE (src) == VAR_DECL || TREE_CODE (src) == PARM_DECL) | |
197 | set_is_used (src); | |
198 | ||
199 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
200 | { | |
201 | fprintf (dump_file, | |
202 | "Inserting a copy on edge BB%d->BB%d :", | |
203 | e->src->index, | |
204 | e->dest->index); | |
205 | print_generic_expr (dump_file, copy, dump_flags); | |
206 | fprintf (dump_file, "\n"); | |
207 | } | |
208 | ||
209 | bsi_insert_on_edge (e, copy); | |
210 | } | |
211 | ||
212 | ||
213 | /* Create an elimination graph with SIZE nodes and associated data | |
214 | structures. */ | |
215 | ||
216 | static elim_graph | |
217 | new_elim_graph (int size) | |
218 | { | |
219 | elim_graph g = (elim_graph) xmalloc (sizeof (struct _elim_graph)); | |
220 | ||
221 | VARRAY_TREE_INIT (g->nodes, 30, "Elimination Node List"); | |
222 | VARRAY_TREE_INIT (g->const_copies, 20, "Elimination Constant Copies"); | |
223 | VARRAY_INT_INIT (g->edge_list, 20, "Elimination Edge List"); | |
224 | VARRAY_INT_INIT (g->stack, 30, " Elimination Stack"); | |
225 | ||
226 | g->visited = sbitmap_alloc (size); | |
227 | ||
228 | return g; | |
229 | } | |
230 | ||
231 | ||
232 | /* Empty elimination graph G. */ | |
233 | ||
234 | static inline void | |
235 | clear_elim_graph (elim_graph g) | |
236 | { | |
237 | VARRAY_POP_ALL (g->nodes); | |
238 | VARRAY_POP_ALL (g->edge_list); | |
239 | } | |
240 | ||
241 | ||
242 | /* Delete elimination graph G. */ | |
243 | ||
244 | static inline void | |
245 | delete_elim_graph (elim_graph g) | |
246 | { | |
247 | sbitmap_free (g->visited); | |
248 | free (g); | |
249 | } | |
250 | ||
251 | ||
252 | /* Return the number of nodes in graph G. */ | |
253 | ||
254 | static inline int | |
255 | elim_graph_size (elim_graph g) | |
256 | { | |
257 | return VARRAY_ACTIVE_SIZE (g->nodes); | |
258 | } | |
259 | ||
260 | ||
261 | /* Add NODE to graph G, if it doesn't exist already. */ | |
262 | ||
263 | static inline void | |
264 | elim_graph_add_node (elim_graph g, tree node) | |
265 | { | |
266 | int x; | |
267 | for (x = 0; x < elim_graph_size (g); x++) | |
268 | if (VARRAY_TREE (g->nodes, x) == node) | |
269 | return; | |
270 | VARRAY_PUSH_TREE (g->nodes, node); | |
271 | } | |
272 | ||
273 | ||
274 | /* Add the edge PRED->SUCC to graph G. */ | |
275 | ||
276 | static inline void | |
277 | elim_graph_add_edge (elim_graph g, int pred, int succ) | |
278 | { | |
279 | VARRAY_PUSH_INT (g->edge_list, pred); | |
280 | VARRAY_PUSH_INT (g->edge_list, succ); | |
281 | } | |
282 | ||
283 | ||
284 | /* Remove an edge from graph G for which NODE is the predecessor, and | |
285 | return the successor node. -1 is returned if there is no such edge. */ | |
286 | ||
287 | static inline int | |
288 | elim_graph_remove_succ_edge (elim_graph g, int node) | |
289 | { | |
290 | int y; | |
291 | unsigned x; | |
292 | for (x = 0; x < VARRAY_ACTIVE_SIZE (g->edge_list); x += 2) | |
293 | if (VARRAY_INT (g->edge_list, x) == node) | |
294 | { | |
295 | VARRAY_INT (g->edge_list, x) = -1; | |
296 | y = VARRAY_INT (g->edge_list, x + 1); | |
297 | VARRAY_INT (g->edge_list, x + 1) = -1; | |
298 | return y; | |
299 | } | |
300 | return -1; | |
301 | } | |
302 | ||
303 | ||
304 | /* Find all the nodes in GRAPH which are successors to NODE in the | |
305 | edge list. VAR will hold the partition number found. CODE is the | |
306 | code fragment executed for every node found. */ | |
307 | ||
308 | #define FOR_EACH_ELIM_GRAPH_SUCC(GRAPH, NODE, VAR, CODE) \ | |
309 | do { \ | |
310 | unsigned x_; \ | |
311 | int y_; \ | |
312 | for (x_ = 0; x_ < VARRAY_ACTIVE_SIZE ((GRAPH)->edge_list); x_ += 2) \ | |
313 | { \ | |
314 | y_ = VARRAY_INT ((GRAPH)->edge_list, x_); \ | |
315 | if (y_ != (NODE)) \ | |
316 | continue; \ | |
317 | (VAR) = VARRAY_INT ((GRAPH)->edge_list, x_ + 1); \ | |
318 | CODE; \ | |
319 | } \ | |
320 | } while (0) | |
321 | ||
322 | ||
323 | /* Find all the nodes which are predecessors of NODE in the edge list for | |
324 | GRAPH. VAR will hold the partition number found. CODE is the | |
325 | code fragment executed for every node found. */ | |
326 | ||
327 | #define FOR_EACH_ELIM_GRAPH_PRED(GRAPH, NODE, VAR, CODE) \ | |
328 | do { \ | |
329 | unsigned x_; \ | |
330 | int y_; \ | |
331 | for (x_ = 0; x_ < VARRAY_ACTIVE_SIZE ((GRAPH)->edge_list); x_ += 2) \ | |
332 | { \ | |
333 | y_ = VARRAY_INT ((GRAPH)->edge_list, x_ + 1); \ | |
334 | if (y_ != (NODE)) \ | |
335 | continue; \ | |
336 | (VAR) = VARRAY_INT ((GRAPH)->edge_list, x_); \ | |
337 | CODE; \ | |
338 | } \ | |
339 | } while (0) | |
340 | ||
341 | ||
342 | /* Add T to elimination graph G. */ | |
343 | ||
344 | static inline void | |
345 | eliminate_name (elim_graph g, tree T) | |
346 | { | |
347 | elim_graph_add_node (g, T); | |
348 | } | |
349 | ||
350 | ||
41f683ef KH |
351 | /* Build elimination graph G for basic block BB on incoming PHI edge |
352 | G->e. */ | |
6de9cd9a DN |
353 | |
354 | static void | |
41f683ef | 355 | eliminate_build (elim_graph g, basic_block B) |
6de9cd9a DN |
356 | { |
357 | tree phi; | |
358 | tree T0, Ti; | |
359 | int p0, pi; | |
360 | ||
361 | clear_elim_graph (g); | |
362 | ||
17192884 | 363 | for (phi = phi_nodes (B); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
364 | { |
365 | T0 = var_to_partition_to_var (g->map, PHI_RESULT (phi)); | |
366 | ||
367 | /* Ignore results which are not in partitions. */ | |
368 | if (T0 == NULL_TREE) | |
369 | continue; | |
370 | ||
41f683ef | 371 | Ti = PHI_ARG_DEF (phi, g->e->dest_idx); |
6de9cd9a DN |
372 | |
373 | /* If this argument is a constant, or a SSA_NAME which is being | |
374 | left in SSA form, just queue a copy to be emitted on this | |
375 | edge. */ | |
376 | if (!phi_ssa_name_p (Ti) | |
377 | || (TREE_CODE (Ti) == SSA_NAME | |
378 | && var_to_partition (g->map, Ti) == NO_PARTITION)) | |
379 | { | |
380 | /* Save constant copies until all other copies have been emitted | |
381 | on this edge. */ | |
382 | VARRAY_PUSH_TREE (g->const_copies, T0); | |
383 | VARRAY_PUSH_TREE (g->const_copies, Ti); | |
384 | } | |
385 | else | |
386 | { | |
387 | Ti = var_to_partition_to_var (g->map, Ti); | |
388 | if (T0 != Ti) | |
389 | { | |
390 | eliminate_name (g, T0); | |
391 | eliminate_name (g, Ti); | |
392 | p0 = var_to_partition (g->map, T0); | |
393 | pi = var_to_partition (g->map, Ti); | |
394 | elim_graph_add_edge (g, p0, pi); | |
395 | } | |
396 | } | |
397 | } | |
398 | } | |
399 | ||
400 | ||
401 | /* Push successors of T onto the elimination stack for G. */ | |
402 | ||
403 | static void | |
404 | elim_forward (elim_graph g, int T) | |
405 | { | |
406 | int S; | |
407 | SET_BIT (g->visited, T); | |
408 | FOR_EACH_ELIM_GRAPH_SUCC (g, T, S, | |
409 | { | |
410 | if (!TEST_BIT (g->visited, S)) | |
411 | elim_forward (g, S); | |
412 | }); | |
413 | VARRAY_PUSH_INT (g->stack, T); | |
414 | } | |
415 | ||
416 | ||
417 | /* Return 1 if there unvisited predecessors of T in graph G. */ | |
418 | ||
419 | static int | |
420 | elim_unvisited_predecessor (elim_graph g, int T) | |
421 | { | |
422 | int P; | |
423 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
424 | { | |
425 | if (!TEST_BIT (g->visited, P)) | |
426 | return 1; | |
427 | }); | |
428 | return 0; | |
429 | } | |
430 | ||
431 | /* Process predecessors first, and insert a copy. */ | |
432 | ||
433 | static void | |
434 | elim_backward (elim_graph g, int T) | |
435 | { | |
436 | int P; | |
437 | SET_BIT (g->visited, T); | |
438 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
439 | { | |
440 | if (!TEST_BIT (g->visited, P)) | |
441 | { | |
442 | elim_backward (g, P); | |
443 | insert_copy_on_edge (g->e, | |
444 | partition_to_var (g->map, P), | |
445 | partition_to_var (g->map, T)); | |
446 | } | |
447 | }); | |
448 | } | |
449 | ||
450 | /* Insert required copies for T in graph G. Check for a strongly connected | |
451 | region, and create a temporary to break the cycle if one is found. */ | |
452 | ||
453 | static void | |
454 | elim_create (elim_graph g, int T) | |
455 | { | |
456 | tree U; | |
457 | int P, S; | |
458 | ||
459 | if (elim_unvisited_predecessor (g, T)) | |
460 | { | |
461 | U = create_temp (partition_to_var (g->map, T)); | |
462 | insert_copy_on_edge (g->e, U, partition_to_var (g->map, T)); | |
463 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
464 | { | |
465 | if (!TEST_BIT (g->visited, P)) | |
466 | { | |
467 | elim_backward (g, P); | |
468 | insert_copy_on_edge (g->e, partition_to_var (g->map, P), U); | |
469 | } | |
470 | }); | |
471 | } | |
472 | else | |
473 | { | |
474 | S = elim_graph_remove_succ_edge (g, T); | |
475 | if (S != -1) | |
476 | { | |
477 | SET_BIT (g->visited, T); | |
478 | insert_copy_on_edge (g->e, | |
479 | partition_to_var (g->map, T), | |
480 | partition_to_var (g->map, S)); | |
481 | } | |
482 | } | |
483 | ||
484 | } | |
485 | ||
41f683ef | 486 | /* Eliminate all the phi nodes on edge E in graph G. */ |
6de9cd9a DN |
487 | |
488 | static void | |
41f683ef | 489 | eliminate_phi (edge e, elim_graph g) |
6de9cd9a | 490 | { |
6de9cd9a DN |
491 | int x; |
492 | basic_block B = e->dest; | |
493 | ||
1e128c5f | 494 | gcc_assert (VARRAY_ACTIVE_SIZE (g->const_copies) == 0); |
6de9cd9a | 495 | |
0e61db61 | 496 | /* Abnormal edges already have everything coalesced. */ |
6de9cd9a DN |
497 | if (e->flags & EDGE_ABNORMAL) |
498 | return; | |
499 | ||
6de9cd9a DN |
500 | g->e = e; |
501 | ||
41f683ef | 502 | eliminate_build (g, B); |
6de9cd9a DN |
503 | |
504 | if (elim_graph_size (g) != 0) | |
505 | { | |
506 | sbitmap_zero (g->visited); | |
507 | VARRAY_POP_ALL (g->stack); | |
508 | ||
509 | for (x = 0; x < elim_graph_size (g); x++) | |
510 | { | |
511 | tree var = VARRAY_TREE (g->nodes, x); | |
512 | int p = var_to_partition (g->map, var); | |
513 | if (!TEST_BIT (g->visited, p)) | |
514 | elim_forward (g, p); | |
515 | } | |
516 | ||
517 | sbitmap_zero (g->visited); | |
518 | while (VARRAY_ACTIVE_SIZE (g->stack) > 0) | |
519 | { | |
520 | x = VARRAY_TOP_INT (g->stack); | |
521 | VARRAY_POP (g->stack); | |
522 | if (!TEST_BIT (g->visited, x)) | |
523 | elim_create (g, x); | |
524 | } | |
525 | } | |
526 | ||
527 | /* If there are any pending constant copies, issue them now. */ | |
528 | while (VARRAY_ACTIVE_SIZE (g->const_copies) > 0) | |
529 | { | |
530 | tree src, dest; | |
531 | src = VARRAY_TOP_TREE (g->const_copies); | |
532 | VARRAY_POP (g->const_copies); | |
533 | dest = VARRAY_TOP_TREE (g->const_copies); | |
534 | VARRAY_POP (g->const_copies); | |
535 | insert_copy_on_edge (e, dest, src); | |
536 | } | |
537 | } | |
538 | ||
539 | ||
540 | /* Shortcut routine to print messages to file F of the form: | |
541 | "STR1 EXPR1 STR2 EXPR2 STR3." */ | |
542 | ||
543 | static void | |
544 | print_exprs (FILE *f, const char *str1, tree expr1, const char *str2, | |
545 | tree expr2, const char *str3) | |
546 | { | |
547 | fprintf (f, "%s", str1); | |
548 | print_generic_expr (f, expr1, TDF_SLIM); | |
549 | fprintf (f, "%s", str2); | |
550 | print_generic_expr (f, expr2, TDF_SLIM); | |
551 | fprintf (f, "%s", str3); | |
552 | } | |
553 | ||
554 | ||
555 | /* Shortcut routine to print abnormal edge messages to file F of the form: | |
556 | "STR1 EXPR1 STR2 EXPR2 across edge E. */ | |
557 | ||
558 | static void | |
559 | print_exprs_edge (FILE *f, edge e, const char *str1, tree expr1, | |
560 | const char *str2, tree expr2) | |
561 | { | |
562 | print_exprs (f, str1, expr1, str2, expr2, " across an abnormal edge"); | |
563 | fprintf (f, " from BB%d->BB%d\n", e->src->index, | |
564 | e->dest->index); | |
565 | } | |
566 | ||
567 | ||
568 | /* Coalesce partitions in MAP which are live across abnormal edges in GRAPH. | |
569 | RV is the root variable groupings of the partitions in MAP. Since code | |
570 | cannot be inserted on these edges, failure to coalesce something across | |
571 | an abnormal edge is an error. */ | |
572 | ||
573 | static void | |
574 | coalesce_abnormal_edges (var_map map, conflict_graph graph, root_var_p rv) | |
575 | { | |
576 | basic_block bb; | |
577 | edge e; | |
578 | tree phi, var, tmp; | |
ff1c708e | 579 | int x, y, z; |
628f6a4e | 580 | edge_iterator ei; |
6de9cd9a DN |
581 | |
582 | /* Code cannot be inserted on abnormal edges. Look for all abnormal | |
583 | edges, and coalesce any PHI results with their arguments across | |
584 | that edge. */ | |
585 | ||
586 | FOR_EACH_BB (bb) | |
628f6a4e | 587 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a | 588 | if (e->dest != EXIT_BLOCK_PTR && e->flags & EDGE_ABNORMAL) |
17192884 | 589 | for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
590 | { |
591 | /* Visit each PHI on the destination side of this abnormal | |
592 | edge, and attempt to coalesce the argument with the result. */ | |
593 | var = PHI_RESULT (phi); | |
594 | x = var_to_partition (map, var); | |
595 | ||
596 | /* Ignore results which are not relevant. */ | |
597 | if (x == NO_PARTITION) | |
598 | continue; | |
599 | ||
be6be258 | 600 | tmp = PHI_ARG_DEF (phi, e->dest_idx); |
1e128c5f | 601 | #ifdef ENABLE_CHECKING |
6de9cd9a DN |
602 | if (!phi_ssa_name_p (tmp)) |
603 | { | |
604 | print_exprs_edge (stderr, e, | |
605 | "\nConstant argument in PHI. Can't insert :", | |
606 | var, " = ", tmp); | |
1e128c5f | 607 | internal_error ("SSA corruption"); |
6de9cd9a | 608 | } |
1e128c5f | 609 | #else |
b49ce401 | 610 | gcc_assert (phi_ssa_name_p (tmp)); |
1e128c5f | 611 | #endif |
6de9cd9a | 612 | y = var_to_partition (map, tmp); |
1e128c5f GB |
613 | gcc_assert (x != NO_PARTITION); |
614 | gcc_assert (y != NO_PARTITION); | |
615 | #ifdef ENABLE_CHECKING | |
6de9cd9a DN |
616 | if (root_var_find (rv, x) != root_var_find (rv, y)) |
617 | { | |
618 | print_exprs_edge (stderr, e, "\nDifferent root vars: ", | |
619 | root_var (rv, root_var_find (rv, x)), | |
620 | " and ", | |
621 | root_var (rv, root_var_find (rv, y))); | |
1e128c5f | 622 | internal_error ("SSA corruption"); |
6de9cd9a | 623 | } |
1e128c5f GB |
624 | #else |
625 | gcc_assert (root_var_find (rv, x) == root_var_find (rv, y)); | |
626 | #endif | |
6de9cd9a DN |
627 | |
628 | if (x != y) | |
629 | { | |
1e128c5f GB |
630 | #ifdef ENABLE_CHECKING |
631 | if (conflict_graph_conflict_p (graph, x, y)) | |
6de9cd9a DN |
632 | { |
633 | print_exprs_edge (stderr, e, "\n Conflict ", | |
634 | partition_to_var (map, x), | |
635 | " and ", partition_to_var (map, y)); | |
1e128c5f | 636 | internal_error ("SSA corruption"); |
6de9cd9a | 637 | } |
1e128c5f GB |
638 | #else |
639 | gcc_assert (!conflict_graph_conflict_p (graph, x, y)); | |
640 | #endif | |
641 | ||
642 | /* Now map the partitions back to their real variables. */ | |
643 | var = partition_to_var (map, x); | |
644 | tmp = partition_to_var (map, y); | |
645 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
646 | { | |
647 | print_exprs_edge (dump_file, e, | |
648 | "ABNORMAL: Coalescing ", | |
649 | var, " and ", tmp); | |
650 | } | |
ff1c708e | 651 | z = var_union (map, var, tmp); |
1e128c5f | 652 | #ifdef ENABLE_CHECKING |
ff1c708e | 653 | if (z == NO_PARTITION) |
1e128c5f GB |
654 | { |
655 | print_exprs_edge (stderr, e, "\nUnable to coalesce", | |
656 | partition_to_var (map, x), " and ", | |
657 | partition_to_var (map, y)); | |
658 | internal_error ("SSA corruption"); | |
659 | } | |
660 | #else | |
ff1c708e | 661 | gcc_assert (z != NO_PARTITION); |
1e128c5f | 662 | #endif |
ff1c708e JL |
663 | gcc_assert (z == x || z == y); |
664 | if (z == x) | |
665 | conflict_graph_merge_regs (graph, x, y); | |
666 | else | |
667 | conflict_graph_merge_regs (graph, y, x); | |
6de9cd9a DN |
668 | } |
669 | } | |
670 | } | |
671 | ||
672 | ||
673 | /* Reduce the number of live ranges in MAP. Live range information is | |
674 | returned if FLAGS indicates that we are combining temporaries, otherwise | |
675 | NULL is returned. The only partitions which are associated with actual | |
676 | variables at this point are those which are forced to be coalesced for | |
677 | various reason. (live on entry, live across abnormal edges, etc.). */ | |
678 | ||
679 | static tree_live_info_p | |
680 | coalesce_ssa_name (var_map map, int flags) | |
681 | { | |
3cd8c58a | 682 | unsigned num, x, i; |
6de9cd9a DN |
683 | sbitmap live; |
684 | tree var, phi; | |
685 | root_var_p rv; | |
686 | tree_live_info_p liveinfo; | |
687 | var_ann_t ann; | |
688 | conflict_graph graph; | |
689 | basic_block bb; | |
690 | coalesce_list_p cl = NULL; | |
691 | ||
692 | if (num_var_partitions (map) <= 1) | |
693 | return NULL; | |
694 | ||
6de9cd9a DN |
695 | liveinfo = calculate_live_on_entry (map); |
696 | calculate_live_on_exit (liveinfo); | |
697 | rv = root_var_init (map); | |
698 | ||
699 | /* Remove single element variable from the list. */ | |
700 | root_var_compact (rv); | |
701 | ||
35bea171 KH |
702 | cl = create_coalesce_list (map); |
703 | ||
704 | /* Add all potential copies via PHI arguments to the list. */ | |
705 | FOR_EACH_BB (bb) | |
6de9cd9a | 706 | { |
35bea171 | 707 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a | 708 | { |
35bea171 KH |
709 | tree res = PHI_RESULT (phi); |
710 | int p = var_to_partition (map, res); | |
711 | if (p == NO_PARTITION) | |
712 | continue; | |
713 | for (x = 0; x < (unsigned)PHI_NUM_ARGS (phi); x++) | |
6de9cd9a | 714 | { |
35bea171 KH |
715 | tree arg = PHI_ARG_DEF (phi, x); |
716 | int p2; | |
717 | ||
718 | if (TREE_CODE (arg) != SSA_NAME) | |
6de9cd9a | 719 | continue; |
35bea171 KH |
720 | if (SSA_NAME_VAR (res) != SSA_NAME_VAR (arg)) |
721 | continue; | |
722 | p2 = var_to_partition (map, PHI_ARG_DEF (phi, x)); | |
723 | if (p2 != NO_PARTITION) | |
724 | add_coalesce (cl, p, p2, 1); | |
6de9cd9a DN |
725 | } |
726 | } | |
35bea171 | 727 | } |
6de9cd9a | 728 | |
35bea171 KH |
729 | /* Coalesce all the result decls together. */ |
730 | var = NULL_TREE; | |
731 | i = 0; | |
732 | for (x = 0; x < num_var_partitions (map); x++) | |
733 | { | |
734 | tree p = partition_to_var (map, x); | |
735 | if (TREE_CODE (SSA_NAME_VAR(p)) == RESULT_DECL) | |
6de9cd9a | 736 | { |
35bea171 | 737 | if (var == NULL_TREE) |
6de9cd9a | 738 | { |
35bea171 KH |
739 | var = p; |
740 | i = x; | |
6de9cd9a | 741 | } |
35bea171 KH |
742 | else |
743 | add_coalesce (cl, i, x, 1); | |
6de9cd9a DN |
744 | } |
745 | } | |
746 | ||
747 | /* Build a conflict graph. */ | |
748 | graph = build_tree_conflict_graph (liveinfo, rv, cl); | |
749 | ||
750 | if (cl) | |
751 | { | |
752 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
753 | { | |
754 | fprintf (dump_file, "Before sorting:\n"); | |
755 | dump_coalesce_list (dump_file, cl); | |
756 | } | |
757 | ||
758 | sort_coalesce_list (cl); | |
759 | ||
760 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
761 | { | |
762 | fprintf (dump_file, "\nAfter sorting:\n"); | |
763 | dump_coalesce_list (dump_file, cl); | |
764 | } | |
765 | } | |
766 | ||
767 | /* Put the single element variables back in. */ | |
768 | root_var_decompact (rv); | |
769 | ||
770 | /* First, coalesce all live on entry variables to their root variable. | |
9cf737f8 | 771 | This will ensure the first use is coming from the correct location. */ |
6de9cd9a DN |
772 | |
773 | live = sbitmap_alloc (num_var_partitions (map)); | |
774 | sbitmap_zero (live); | |
775 | ||
776 | /* Set 'live' vector to indicate live on entry partitions. */ | |
777 | num = num_var_partitions (map); | |
778 | for (x = 0 ; x < num; x++) | |
779 | { | |
780 | var = partition_to_var (map, x); | |
781 | if (default_def (SSA_NAME_VAR (var)) == var) | |
782 | SET_BIT (live, x); | |
783 | } | |
784 | ||
785 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
786 | { | |
787 | delete_tree_live_info (liveinfo); | |
788 | liveinfo = NULL; | |
789 | } | |
790 | ||
791 | /* Assign root variable as partition representative for each live on entry | |
792 | partition. */ | |
793 | EXECUTE_IF_SET_IN_SBITMAP (live, 0, x, | |
794 | { | |
795 | var = root_var (rv, root_var_find (rv, x)); | |
796 | ann = var_ann (var); | |
797 | /* If these aren't already coalesced... */ | |
798 | if (partition_to_var (map, x) != var) | |
799 | { | |
1e128c5f GB |
800 | /* This root variable should have not already been assigned |
801 | to another partition which is not coalesced with this one. */ | |
802 | gcc_assert (!ann->out_of_ssa_tag); | |
6de9cd9a DN |
803 | |
804 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
805 | { | |
806 | print_exprs (dump_file, "Must coalesce ", | |
807 | partition_to_var (map, x), | |
808 | " with the root variable ", var, ".\n"); | |
809 | } | |
810 | ||
811 | change_partition_var (map, var, x); | |
812 | } | |
813 | }); | |
814 | ||
815 | sbitmap_free (live); | |
816 | ||
817 | /* Coalesce partitions live across abnormal edges. */ | |
818 | coalesce_abnormal_edges (map, graph, rv); | |
819 | ||
820 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
821 | dump_var_map (dump_file, map); | |
822 | ||
823 | /* Coalesce partitions. */ | |
35bea171 KH |
824 | coalesce_tpa_members (rv, graph, map, cl, |
825 | ((dump_flags & TDF_DETAILS) ? dump_file | |
826 | : NULL)); | |
6de9cd9a | 827 | |
6de9cd9a | 828 | if (flags & SSANORM_COALESCE_PARTITIONS) |
35bea171 KH |
829 | coalesce_tpa_members (rv, graph, map, NULL, |
830 | ((dump_flags & TDF_DETAILS) ? dump_file | |
831 | : NULL)); | |
6de9cd9a DN |
832 | if (cl) |
833 | delete_coalesce_list (cl); | |
834 | root_var_delete (rv); | |
835 | conflict_graph_delete (graph); | |
836 | ||
837 | return liveinfo; | |
838 | } | |
839 | ||
840 | ||
841 | /* Take the ssa-name var_map MAP, and assign real variables to each | |
842 | partition. */ | |
843 | ||
844 | static void | |
845 | assign_vars (var_map map) | |
846 | { | |
847 | int x, i, num, rep; | |
848 | tree t, var; | |
849 | var_ann_t ann; | |
850 | root_var_p rv; | |
851 | ||
852 | rv = root_var_init (map); | |
853 | if (!rv) | |
854 | return; | |
855 | ||
856 | /* Coalescing may already have forced some partitions to their root | |
857 | variable. Find these and tag them. */ | |
858 | ||
859 | num = num_var_partitions (map); | |
860 | for (x = 0; x < num; x++) | |
861 | { | |
862 | var = partition_to_var (map, x); | |
863 | if (TREE_CODE (var) != SSA_NAME) | |
864 | { | |
865 | /* Coalescing will already have verified that more than one | |
866 | partition doesn't have the same root variable. Simply marked | |
867 | the variable as assigned. */ | |
868 | ann = var_ann (var); | |
869 | ann->out_of_ssa_tag = 1; | |
870 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
871 | { | |
872 | fprintf (dump_file, "partition %d has variable ", x); | |
873 | print_generic_expr (dump_file, var, TDF_SLIM); | |
874 | fprintf (dump_file, " assigned to it.\n"); | |
875 | } | |
876 | ||
877 | } | |
878 | } | |
879 | ||
880 | num = root_var_num (rv); | |
881 | for (x = 0; x < num; x++) | |
882 | { | |
883 | var = root_var (rv, x); | |
884 | ann = var_ann (var); | |
885 | for (i = root_var_first_partition (rv, x); | |
886 | i != ROOT_VAR_NONE; | |
887 | i = root_var_next_partition (rv, i)) | |
888 | { | |
889 | t = partition_to_var (map, i); | |
890 | ||
891 | if (t == var || TREE_CODE (t) != SSA_NAME) | |
892 | continue; | |
893 | ||
894 | rep = var_to_partition (map, t); | |
895 | ||
896 | if (!ann->out_of_ssa_tag) | |
897 | { | |
898 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
899 | print_exprs (dump_file, "", t, " --> ", var, "\n"); | |
900 | change_partition_var (map, var, rep); | |
901 | continue; | |
902 | } | |
903 | ||
904 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
905 | print_exprs (dump_file, "", t, " not coalesced with ", var, | |
906 | ""); | |
907 | ||
908 | var = create_temp (t); | |
909 | change_partition_var (map, var, rep); | |
910 | ann = var_ann (var); | |
911 | ||
912 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
913 | { | |
914 | fprintf (dump_file, " --> New temp: '"); | |
915 | print_generic_expr (dump_file, var, TDF_SLIM); | |
916 | fprintf (dump_file, "'\n"); | |
917 | } | |
918 | } | |
919 | } | |
920 | ||
921 | root_var_delete (rv); | |
922 | } | |
923 | ||
924 | ||
d00ad49b AM |
925 | /* Replace use operand P with whatever variable it has been rewritten to based |
926 | on the partitions in MAP. EXPR is an optional expression vector over SSA | |
927 | versions which is used to replace P with an expression instead of a variable. | |
6de9cd9a DN |
928 | If the stmt is changed, return true. */ |
929 | ||
930 | static inline bool | |
d00ad49b | 931 | replace_use_variable (var_map map, use_operand_p p, tree *expr) |
6de9cd9a DN |
932 | { |
933 | tree new_var; | |
d00ad49b | 934 | tree var = USE_FROM_PTR (p); |
6de9cd9a DN |
935 | |
936 | /* Check if we are replacing this variable with an expression. */ | |
937 | if (expr) | |
938 | { | |
d00ad49b | 939 | int version = SSA_NAME_VERSION (var); |
6de9cd9a DN |
940 | if (expr[version]) |
941 | { | |
942 | tree new_expr = TREE_OPERAND (expr[version], 1); | |
d00ad49b | 943 | SET_USE (p, new_expr); |
6de9cd9a DN |
944 | /* Clear the stmt's RHS, or GC might bite us. */ |
945 | TREE_OPERAND (expr[version], 1) = NULL_TREE; | |
946 | return true; | |
947 | } | |
948 | } | |
949 | ||
950 | new_var = var_to_partition_to_var (map, var); | |
951 | if (new_var) | |
952 | { | |
d00ad49b AM |
953 | SET_USE (p, new_var); |
954 | set_is_used (new_var); | |
955 | return true; | |
956 | } | |
957 | return false; | |
958 | } | |
959 | ||
960 | ||
961 | /* Replace def operand DEF_P with whatever variable it has been rewritten to | |
962 | based on the partitions in MAP. EXPR is an optional expression vector over | |
963 | SSA versions which is used to replace DEF_P with an expression instead of a | |
964 | variable. If the stmt is changed, return true. */ | |
965 | ||
966 | static inline bool | |
967 | replace_def_variable (var_map map, def_operand_p def_p, tree *expr) | |
968 | { | |
969 | tree new_var; | |
970 | tree var = DEF_FROM_PTR (def_p); | |
971 | ||
972 | /* Check if we are replacing this variable with an expression. */ | |
973 | if (expr) | |
974 | { | |
975 | int version = SSA_NAME_VERSION (var); | |
976 | if (expr[version]) | |
977 | { | |
978 | tree new_expr = TREE_OPERAND (expr[version], 1); | |
979 | SET_DEF (def_p, new_expr); | |
980 | /* Clear the stmt's RHS, or GC might bite us. */ | |
981 | TREE_OPERAND (expr[version], 1) = NULL_TREE; | |
982 | return true; | |
983 | } | |
984 | } | |
985 | ||
986 | new_var = var_to_partition_to_var (map, var); | |
987 | if (new_var) | |
988 | { | |
989 | SET_DEF (def_p, new_var); | |
6de9cd9a DN |
990 | set_is_used (new_var); |
991 | return true; | |
992 | } | |
993 | return false; | |
994 | } | |
995 | ||
996 | ||
997 | /* Remove any PHI node which is a virtual PHI. */ | |
998 | ||
999 | static void | |
1000 | eliminate_virtual_phis (void) | |
1001 | { | |
1002 | basic_block bb; | |
1003 | tree phi, next; | |
1004 | ||
1005 | FOR_EACH_BB (bb) | |
1006 | { | |
1007 | for (phi = phi_nodes (bb); phi; phi = next) | |
1008 | { | |
17192884 | 1009 | next = PHI_CHAIN (phi); |
6de9cd9a DN |
1010 | if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi)))) |
1011 | { | |
1012 | #ifdef ENABLE_CHECKING | |
1013 | int i; | |
1014 | /* There should be no arguments of this PHI which are in | |
1015 | the partition list, or we get incorrect results. */ | |
1016 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
1017 | { | |
1018 | tree arg = PHI_ARG_DEF (phi, i); | |
1019 | if (TREE_CODE (arg) == SSA_NAME | |
1020 | && is_gimple_reg (SSA_NAME_VAR (arg))) | |
1021 | { | |
1022 | fprintf (stderr, "Argument of PHI is not virtual ("); | |
1023 | print_generic_expr (stderr, arg, TDF_SLIM); | |
1024 | fprintf (stderr, "), but the result is :"); | |
1025 | print_generic_stmt (stderr, phi, TDF_SLIM); | |
1e128c5f | 1026 | internal_error ("SSA corruption"); |
6de9cd9a DN |
1027 | } |
1028 | } | |
1029 | #endif | |
d19e3ef6 | 1030 | remove_phi_node (phi, NULL_TREE); |
6de9cd9a DN |
1031 | } |
1032 | } | |
1033 | } | |
1034 | } | |
1035 | ||
1036 | ||
1037 | /* This routine will coalesce variables in MAP of the same type which do not | |
1038 | interfere with each other. LIVEINFO is the live range info for variables | |
1039 | of interest. This will both reduce the memory footprint of the stack, and | |
1040 | allow us to coalesce together local copies of globals and scalarized | |
1041 | component refs. */ | |
1042 | ||
1043 | static void | |
1044 | coalesce_vars (var_map map, tree_live_info_p liveinfo) | |
1045 | { | |
1046 | basic_block bb; | |
1047 | type_var_p tv; | |
1048 | tree var; | |
3cd8c58a | 1049 | unsigned x, p, p2; |
6de9cd9a DN |
1050 | coalesce_list_p cl; |
1051 | conflict_graph graph; | |
1052 | ||
1053 | cl = create_coalesce_list (map); | |
1054 | ||
1055 | /* Merge all the live on entry vectors for coalesced partitions. */ | |
1056 | for (x = 0; x < num_var_partitions (map); x++) | |
1057 | { | |
1058 | var = partition_to_var (map, x); | |
1059 | p = var_to_partition (map, var); | |
1060 | if (p != x) | |
1061 | live_merge_and_clear (liveinfo, p, x); | |
1062 | } | |
1063 | ||
1064 | /* When PHI nodes are turned into copies, the result of each PHI node | |
1065 | becomes live on entry to the block. Mark these now. */ | |
1066 | FOR_EACH_BB (bb) | |
1067 | { | |
1068 | tree phi, arg; | |
3cd8c58a NS |
1069 | unsigned p; |
1070 | ||
17192884 | 1071 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
1072 | { |
1073 | p = var_to_partition (map, PHI_RESULT (phi)); | |
1074 | ||
1075 | /* Skip virtual PHI nodes. */ | |
3cd8c58a | 1076 | if (p == (unsigned)NO_PARTITION) |
6de9cd9a DN |
1077 | continue; |
1078 | ||
1079 | make_live_on_entry (liveinfo, bb, p); | |
1080 | ||
1081 | /* Each argument is a potential copy operation. Add any arguments | |
1082 | which are not coalesced to the result to the coalesce list. */ | |
3cd8c58a | 1083 | for (x = 0; x < (unsigned)PHI_NUM_ARGS (phi); x++) |
6de9cd9a DN |
1084 | { |
1085 | arg = PHI_ARG_DEF (phi, x); | |
1086 | if (!phi_ssa_name_p (arg)) | |
1087 | continue; | |
1088 | p2 = var_to_partition (map, arg); | |
3cd8c58a | 1089 | if (p2 == (unsigned)NO_PARTITION) |
6de9cd9a DN |
1090 | continue; |
1091 | if (p != p2) | |
1092 | add_coalesce (cl, p, p2, 1); | |
1093 | } | |
1094 | } | |
1095 | } | |
1096 | ||
1097 | ||
1098 | /* Re-calculate live on exit info. */ | |
1099 | calculate_live_on_exit (liveinfo); | |
1100 | ||
1101 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1102 | { | |
1103 | fprintf (dump_file, "Live range info for variable memory coalescing.\n"); | |
1104 | dump_live_info (dump_file, liveinfo, LIVEDUMP_ALL); | |
1105 | ||
1106 | fprintf (dump_file, "Coalesce list from phi nodes:\n"); | |
1107 | dump_coalesce_list (dump_file, cl); | |
1108 | } | |
1109 | ||
1110 | ||
1111 | tv = type_var_init (map); | |
1112 | if (dump_file) | |
1113 | type_var_dump (dump_file, tv); | |
1114 | type_var_compact (tv); | |
1115 | if (dump_file) | |
1116 | type_var_dump (dump_file, tv); | |
1117 | ||
1118 | graph = build_tree_conflict_graph (liveinfo, tv, cl); | |
1119 | ||
1120 | type_var_decompact (tv); | |
1121 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1122 | { | |
1123 | fprintf (dump_file, "type var list now looks like:n"); | |
1124 | type_var_dump (dump_file, tv); | |
1125 | ||
1126 | fprintf (dump_file, "Coalesce list after conflict graph build:\n"); | |
1127 | dump_coalesce_list (dump_file, cl); | |
1128 | } | |
1129 | ||
1130 | sort_coalesce_list (cl); | |
1131 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1132 | { | |
1133 | fprintf (dump_file, "Coalesce list after sorting:\n"); | |
1134 | dump_coalesce_list (dump_file, cl); | |
1135 | } | |
1136 | ||
1137 | coalesce_tpa_members (tv, graph, map, cl, | |
1138 | ((dump_flags & TDF_DETAILS) ? dump_file : NULL)); | |
1139 | ||
1140 | type_var_delete (tv); | |
1141 | delete_coalesce_list (cl); | |
1142 | } | |
1143 | ||
1144 | ||
1145 | /* Temporary Expression Replacement (TER) | |
1146 | ||
1147 | Replace SSA version variables during out-of-ssa with their defining | |
1148 | expression if there is only one use of the variable. | |
1149 | ||
1150 | A pass is made through the function, one block at a time. No cross block | |
1151 | information is tracked. | |
1152 | ||
1153 | Variables which only have one use, and whose defining stmt is considered | |
1154 | a replaceable expression (see check_replaceable) are entered into | |
1155 | consideration by adding a list of dependent partitions to the version_info | |
1156 | vector for that ssa_name_version. This information comes from the partition | |
1157 | mapping for each USE. At the same time, the partition_dep_list vector for | |
1158 | these partitions have this version number entered into their lists. | |
1159 | ||
1160 | When the use of a replaceable ssa_variable is encountered, the dependence | |
1161 | list in version_info[] is moved to the "pending_dependence" list in case | |
1162 | the current expression is also replaceable. (To be determined later in | |
1163 | processing this stmt.) version_info[] for the version is then updated to | |
1164 | point to the defining stmt and the 'replaceable' bit is set. | |
1165 | ||
1166 | Any partition which is defined by a statement 'kills' any expression which | |
1167 | is dependent on this partition. Every ssa version in the partitions' | |
1168 | dependence list is removed from future consideration. | |
1169 | ||
1170 | All virtual references are lumped together. Any expression which is | |
1171 | dependent on any virtual variable (via a VUSE) has a dependence added | |
1172 | to the special partition defined by VIRTUAL_PARTITION. | |
1173 | ||
a32b97a2 BB |
1174 | Whenever a V_MAY_DEF is seen, all expressions dependent this |
1175 | VIRTUAL_PARTITION are removed from consideration. | |
6de9cd9a DN |
1176 | |
1177 | At the end of a basic block, all expression are removed from consideration | |
1178 | in preparation for the next block. | |
1179 | ||
1180 | The end result is a vector over SSA_NAME_VERSION which is passed back to | |
1181 | rewrite_out_of_ssa. As the SSA variables are being rewritten, instead of | |
1182 | replacing the SSA_NAME tree element with the partition it was assigned, | |
1183 | it is replaced with the RHS of the defining expression. */ | |
1184 | ||
1185 | ||
61ada8ae | 1186 | /* Dependency list element. This can contain either a partition index or a |
6de9cd9a DN |
1187 | version number, depending on which list it is in. */ |
1188 | ||
1189 | typedef struct value_expr_d | |
1190 | { | |
1191 | int value; | |
1192 | struct value_expr_d *next; | |
1193 | } *value_expr_p; | |
1194 | ||
1195 | ||
1196 | /* Temporary Expression Replacement (TER) table information. */ | |
1197 | ||
1198 | typedef struct temp_expr_table_d | |
1199 | { | |
1200 | var_map map; | |
1201 | void **version_info; | |
1202 | value_expr_p *partition_dep_list; | |
1203 | bitmap replaceable; | |
1204 | bool saw_replaceable; | |
1205 | int virtual_partition; | |
1206 | bitmap partition_in_use; | |
1207 | value_expr_p free_list; | |
1208 | value_expr_p pending_dependence; | |
1209 | } *temp_expr_table_p; | |
1210 | ||
61ada8ae | 1211 | /* Used to indicate a dependency on V_MAY_DEFs. */ |
6de9cd9a DN |
1212 | #define VIRTUAL_PARTITION(table) (table->virtual_partition) |
1213 | ||
1214 | static temp_expr_table_p new_temp_expr_table (var_map); | |
1215 | static tree *free_temp_expr_table (temp_expr_table_p); | |
1216 | static inline value_expr_p new_value_expr (temp_expr_table_p); | |
1217 | static inline void free_value_expr (temp_expr_table_p, value_expr_p); | |
1218 | static inline value_expr_p find_value_in_list (value_expr_p, int, | |
1219 | value_expr_p *); | |
1220 | static inline void add_value_to_list (temp_expr_table_p, value_expr_p *, int); | |
1221 | static inline void add_info_to_list (temp_expr_table_p, value_expr_p *, | |
1222 | value_expr_p); | |
1223 | static value_expr_p remove_value_from_list (value_expr_p *, int); | |
1224 | static void add_dependance (temp_expr_table_p, int, tree); | |
1225 | static bool check_replaceable (temp_expr_table_p, tree); | |
1226 | static void finish_expr (temp_expr_table_p, int, bool); | |
1227 | static void mark_replaceable (temp_expr_table_p, tree); | |
1228 | static inline void kill_expr (temp_expr_table_p, int, bool); | |
1229 | static inline void kill_virtual_exprs (temp_expr_table_p, bool); | |
1230 | static void find_replaceable_in_bb (temp_expr_table_p, basic_block); | |
1231 | static tree *find_replaceable_exprs (var_map); | |
1232 | static void dump_replaceable_exprs (FILE *, tree *); | |
1233 | ||
1234 | ||
1235 | /* Create a new TER table for MAP. */ | |
1236 | ||
1237 | static temp_expr_table_p | |
1238 | new_temp_expr_table (var_map map) | |
1239 | { | |
1240 | temp_expr_table_p t; | |
1241 | ||
1242 | t = (temp_expr_table_p) xmalloc (sizeof (struct temp_expr_table_d)); | |
1243 | t->map = map; | |
1244 | ||
95a3742c | 1245 | t->version_info = xcalloc (num_ssa_names + 1, sizeof (void *)); |
6de9cd9a DN |
1246 | t->partition_dep_list = xcalloc (num_var_partitions (map) + 1, |
1247 | sizeof (value_expr_p)); | |
1248 | ||
8bdbfff5 NS |
1249 | t->replaceable = BITMAP_ALLOC (NULL); |
1250 | t->partition_in_use = BITMAP_ALLOC (NULL); | |
6de9cd9a DN |
1251 | |
1252 | t->saw_replaceable = false; | |
1253 | t->virtual_partition = num_var_partitions (map); | |
1254 | t->free_list = NULL; | |
1255 | t->pending_dependence = NULL; | |
1256 | ||
1257 | return t; | |
1258 | } | |
1259 | ||
1260 | ||
1261 | /* Free TER table T. If there are valid replacements, return the expression | |
1262 | vector. */ | |
1263 | ||
1264 | static tree * | |
1265 | free_temp_expr_table (temp_expr_table_p t) | |
1266 | { | |
1267 | value_expr_p p; | |
1268 | tree *ret = NULL; | |
1269 | ||
1270 | #ifdef ENABLE_CHECKING | |
3cd8c58a | 1271 | unsigned x; |
6de9cd9a | 1272 | for (x = 0; x <= num_var_partitions (t->map); x++) |
e1537934 | 1273 | gcc_assert (!t->partition_dep_list[x]); |
6de9cd9a DN |
1274 | #endif |
1275 | ||
1276 | while ((p = t->free_list)) | |
1277 | { | |
1278 | t->free_list = p->next; | |
1279 | free (p); | |
1280 | } | |
1281 | ||
8bdbfff5 NS |
1282 | BITMAP_FREE (t->partition_in_use); |
1283 | BITMAP_FREE (t->replaceable); | |
6de9cd9a DN |
1284 | |
1285 | free (t->partition_dep_list); | |
1286 | if (t->saw_replaceable) | |
1287 | ret = (tree *)t->version_info; | |
1288 | else | |
1289 | free (t->version_info); | |
1290 | ||
1291 | free (t); | |
1292 | return ret; | |
1293 | } | |
1294 | ||
1295 | ||
1296 | /* Allocate a new value list node. Take it from the free list in TABLE if | |
1297 | possible. */ | |
1298 | ||
1299 | static inline value_expr_p | |
1300 | new_value_expr (temp_expr_table_p table) | |
1301 | { | |
1302 | value_expr_p p; | |
1303 | if (table->free_list) | |
1304 | { | |
1305 | p = table->free_list; | |
1306 | table->free_list = p->next; | |
1307 | } | |
1308 | else | |
1309 | p = (value_expr_p) xmalloc (sizeof (struct value_expr_d)); | |
1310 | ||
1311 | return p; | |
1312 | } | |
1313 | ||
1314 | ||
1315 | /* Add value list node P to the free list in TABLE. */ | |
1316 | ||
1317 | static inline void | |
1318 | free_value_expr (temp_expr_table_p table, value_expr_p p) | |
1319 | { | |
1320 | p->next = table->free_list; | |
1321 | table->free_list = p; | |
1322 | } | |
1323 | ||
1324 | ||
1dee9d0d | 1325 | /* Find VALUE if it's in LIST. Return a pointer to the list object if found, |
6de9cd9a DN |
1326 | else return NULL. If LAST_PTR is provided, it will point to the previous |
1327 | item upon return, or NULL if this is the first item in the list. */ | |
1328 | ||
1329 | static inline value_expr_p | |
1330 | find_value_in_list (value_expr_p list, int value, value_expr_p *last_ptr) | |
1331 | { | |
1332 | value_expr_p curr; | |
1333 | value_expr_p last = NULL; | |
1334 | ||
1335 | for (curr = list; curr; last = curr, curr = curr->next) | |
1336 | { | |
1337 | if (curr->value == value) | |
1338 | break; | |
1339 | } | |
1340 | if (last_ptr) | |
1341 | *last_ptr = last; | |
1342 | return curr; | |
1343 | } | |
1344 | ||
1345 | ||
1346 | /* Add VALUE to LIST, if it isn't already present. TAB is the expression | |
1347 | table */ | |
1348 | ||
1349 | static inline void | |
1350 | add_value_to_list (temp_expr_table_p tab, value_expr_p *list, int value) | |
1351 | { | |
1352 | value_expr_p info; | |
1353 | ||
1354 | if (!find_value_in_list (*list, value, NULL)) | |
1355 | { | |
1356 | info = new_value_expr (tab); | |
1357 | info->value = value; | |
1358 | info->next = *list; | |
1359 | *list = info; | |
1360 | } | |
1361 | } | |
1362 | ||
1363 | ||
1364 | /* Add value node INFO if it's value isn't already in LIST. Free INFO if | |
1365 | it is already in the list. TAB is the expression table. */ | |
1366 | ||
1367 | static inline void | |
1368 | add_info_to_list (temp_expr_table_p tab, value_expr_p *list, value_expr_p info) | |
1369 | { | |
1370 | if (find_value_in_list (*list, info->value, NULL)) | |
1371 | free_value_expr (tab, info); | |
1372 | else | |
1373 | { | |
1374 | info->next = *list; | |
1375 | *list = info; | |
1376 | } | |
1377 | } | |
1378 | ||
1379 | ||
1380 | /* Look for VALUE in LIST. If found, remove it from the list and return it's | |
1381 | pointer. */ | |
1382 | ||
1383 | static value_expr_p | |
1384 | remove_value_from_list (value_expr_p *list, int value) | |
1385 | { | |
1386 | value_expr_p info, last; | |
1387 | ||
1388 | info = find_value_in_list (*list, value, &last); | |
1389 | if (!info) | |
1390 | return NULL; | |
1391 | if (!last) | |
1392 | *list = info->next; | |
1393 | else | |
1394 | last->next = info->next; | |
1395 | ||
1396 | return info; | |
1397 | } | |
1398 | ||
1399 | ||
61ada8ae KH |
1400 | /* Add a dependency between the def of ssa VERSION and VAR. If VAR is |
1401 | replaceable by an expression, add a dependence each of the elements of the | |
6de9cd9a DN |
1402 | expression. These are contained in the pending list. TAB is the |
1403 | expression table. */ | |
1404 | ||
1405 | static void | |
1406 | add_dependance (temp_expr_table_p tab, int version, tree var) | |
1407 | { | |
1408 | int i, x; | |
1409 | value_expr_p info; | |
1410 | ||
1411 | i = SSA_NAME_VERSION (var); | |
1412 | if (bitmap_bit_p (tab->replaceable, i)) | |
1413 | { | |
1414 | /* This variable is being substituted, so use whatever dependences | |
1415 | were queued up when we marked this as replaceable earlier. */ | |
1416 | while ((info = tab->pending_dependence)) | |
1417 | { | |
1418 | tab->pending_dependence = info->next; | |
1419 | /* Get the partition this variable was dependent on. Reuse this | |
1420 | object to represent the current expression instead. */ | |
1421 | x = info->value; | |
1422 | info->value = version; | |
1423 | add_info_to_list (tab, &(tab->partition_dep_list[x]), info); | |
1424 | add_value_to_list (tab, | |
1425 | (value_expr_p *)&(tab->version_info[version]), x); | |
1426 | bitmap_set_bit (tab->partition_in_use, x); | |
1427 | } | |
1428 | } | |
1429 | else | |
1430 | { | |
1431 | i = var_to_partition (tab->map, var); | |
1e128c5f | 1432 | gcc_assert (i != NO_PARTITION); |
6de9cd9a DN |
1433 | add_value_to_list (tab, &(tab->partition_dep_list[i]), version); |
1434 | add_value_to_list (tab, | |
1435 | (value_expr_p *)&(tab->version_info[version]), i); | |
1436 | bitmap_set_bit (tab->partition_in_use, i); | |
1437 | } | |
1438 | } | |
1439 | ||
1440 | ||
1441 | /* Check if expression STMT is suitable for replacement in table TAB. If so, | |
1442 | create an expression entry. Return true if this stmt is replaceable. */ | |
1443 | ||
1444 | static bool | |
1445 | check_replaceable (temp_expr_table_p tab, tree stmt) | |
1446 | { | |
1447 | stmt_ann_t ann; | |
1448 | vuse_optype vuseops; | |
1449 | def_optype defs; | |
1450 | use_optype uses; | |
1451 | tree var, def; | |
4c124b4c | 1452 | int num_use_ops, version; |
6de9cd9a | 1453 | var_map map = tab->map; |
4c124b4c | 1454 | ssa_op_iter iter; |
87637d21 | 1455 | tree call_expr; |
6de9cd9a DN |
1456 | |
1457 | if (TREE_CODE (stmt) != MODIFY_EXPR) | |
1458 | return false; | |
1459 | ||
1460 | ann = stmt_ann (stmt); | |
1461 | defs = DEF_OPS (ann); | |
1462 | ||
1463 | /* Punt if there is more than 1 def, or more than 1 use. */ | |
1464 | if (NUM_DEFS (defs) != 1) | |
1465 | return false; | |
1466 | def = DEF_OP (defs, 0); | |
1467 | if (version_ref_count (map, def) != 1) | |
1468 | return false; | |
1469 | ||
a32b97a2 BB |
1470 | /* There must be no V_MAY_DEFS. */ |
1471 | if (NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann)) != 0) | |
1472 | return false; | |
1473 | ||
1474 | /* There must be no V_MUST_DEFS. */ | |
1475 | if (NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann)) != 0) | |
6de9cd9a DN |
1476 | return false; |
1477 | ||
1478 | /* Float expressions must go through memory if float-store is on. */ | |
1479 | if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (stmt, 1)))) | |
1480 | return false; | |
1481 | ||
87637d21 DN |
1482 | /* Calls to functions with side-effects cannot be replaced. */ |
1483 | if ((call_expr = get_call_expr_in (stmt)) != NULL_TREE) | |
1484 | { | |
1485 | int call_flags = call_expr_flags (call_expr); | |
1486 | if (TREE_SIDE_EFFECTS (call_expr) | |
1487 | && !(call_flags & (ECF_PURE | ECF_CONST | ECF_NORETURN))) | |
1488 | return false; | |
1489 | } | |
1490 | ||
6de9cd9a DN |
1491 | uses = USE_OPS (ann); |
1492 | num_use_ops = NUM_USES (uses); | |
1493 | vuseops = VUSE_OPS (ann); | |
1494 | ||
1495 | /* Any expression which has no virtual operands and no real operands | |
1496 | should have been propagated if it's possible to do anything with them. | |
1497 | If this happens here, it probably exists that way for a reason, so we | |
1498 | won't touch it. An example is: | |
1499 | b_4 = &tab | |
1500 | There are no virtual uses nor any real uses, so we just leave this | |
1501 | alone to be safe. */ | |
1502 | ||
1503 | if (num_use_ops == 0 && NUM_VUSES (vuseops) == 0) | |
1504 | return false; | |
1505 | ||
1506 | version = SSA_NAME_VERSION (def); | |
1507 | ||
61ada8ae | 1508 | /* Add this expression to the dependency list for each use partition. */ |
4c124b4c | 1509 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1510 | { |
6de9cd9a DN |
1511 | add_dependance (tab, version, var); |
1512 | } | |
1513 | ||
1514 | /* If there are VUSES, add a dependence on virtual defs. */ | |
1515 | if (NUM_VUSES (vuseops) != 0) | |
1516 | { | |
1517 | add_value_to_list (tab, (value_expr_p *)&(tab->version_info[version]), | |
1518 | VIRTUAL_PARTITION (tab)); | |
1519 | add_value_to_list (tab, | |
1520 | &(tab->partition_dep_list[VIRTUAL_PARTITION (tab)]), | |
1521 | version); | |
1522 | bitmap_set_bit (tab->partition_in_use, VIRTUAL_PARTITION (tab)); | |
1523 | } | |
1524 | ||
1525 | return true; | |
1526 | } | |
1527 | ||
1528 | ||
1529 | /* This function will remove the expression for VERSION from replacement | |
1530 | consideration.n table TAB If 'replace' is true, it is marked as | |
1531 | replaceable, otherwise not. */ | |
1532 | ||
1533 | static void | |
1534 | finish_expr (temp_expr_table_p tab, int version, bool replace) | |
1535 | { | |
1536 | value_expr_p info, tmp; | |
1537 | int partition; | |
1538 | ||
61ada8ae | 1539 | /* Remove this expression from its dependent lists. The partition dependence |
6de9cd9a DN |
1540 | list is retained and transfered later to whomever uses this version. */ |
1541 | for (info = (value_expr_p) tab->version_info[version]; info; info = tmp) | |
1542 | { | |
1543 | partition = info->value; | |
1e128c5f | 1544 | gcc_assert (tab->partition_dep_list[partition]); |
6de9cd9a DN |
1545 | tmp = remove_value_from_list (&(tab->partition_dep_list[partition]), |
1546 | version); | |
1e128c5f | 1547 | gcc_assert (tmp); |
6de9cd9a | 1548 | free_value_expr (tab, tmp); |
61ada8ae | 1549 | /* Only clear the bit when the dependency list is emptied via |
6de9cd9a DN |
1550 | a replacement. Otherwise kill_expr will take care of it. */ |
1551 | if (!(tab->partition_dep_list[partition]) && replace) | |
1552 | bitmap_clear_bit (tab->partition_in_use, partition); | |
1553 | tmp = info->next; | |
1554 | if (!replace) | |
1555 | free_value_expr (tab, info); | |
1556 | } | |
1557 | ||
1558 | if (replace) | |
1559 | { | |
1560 | tab->saw_replaceable = true; | |
1561 | bitmap_set_bit (tab->replaceable, version); | |
1562 | } | |
1563 | else | |
1564 | { | |
1e128c5f | 1565 | gcc_assert (!bitmap_bit_p (tab->replaceable, version)); |
6de9cd9a DN |
1566 | tab->version_info[version] = NULL; |
1567 | } | |
1568 | } | |
1569 | ||
1570 | ||
1571 | /* Mark the expression associated with VAR as replaceable, and enter | |
1572 | the defining stmt into the version_info table TAB. */ | |
1573 | ||
1574 | static void | |
1575 | mark_replaceable (temp_expr_table_p tab, tree var) | |
1576 | { | |
1577 | value_expr_p info; | |
1578 | int version = SSA_NAME_VERSION (var); | |
1579 | finish_expr (tab, version, true); | |
1580 | ||
1581 | /* Move the dependence list to the pending list. */ | |
1582 | if (tab->version_info[version]) | |
1583 | { | |
1584 | info = (value_expr_p) tab->version_info[version]; | |
1585 | for ( ; info->next; info = info->next) | |
1586 | continue; | |
1587 | info->next = tab->pending_dependence; | |
1588 | tab->pending_dependence = (value_expr_p)tab->version_info[version]; | |
1589 | } | |
1590 | ||
1591 | tab->version_info[version] = SSA_NAME_DEF_STMT (var); | |
1592 | } | |
1593 | ||
1594 | ||
1595 | /* This function marks any expression in TAB which is dependent on PARTITION | |
1596 | as NOT replaceable. CLEAR_BIT is used to determine whether partition_in_use | |
1597 | should have its bit cleared. Since this routine can be called within an | |
1598 | EXECUTE_IF_SET_IN_BITMAP, the bit can't always be cleared. */ | |
1599 | ||
1600 | static inline void | |
1601 | kill_expr (temp_expr_table_p tab, int partition, bool clear_bit) | |
1602 | { | |
1603 | value_expr_p ptr; | |
1604 | ||
61ada8ae | 1605 | /* Mark every active expr dependent on this var as not replaceable. */ |
6de9cd9a DN |
1606 | while ((ptr = tab->partition_dep_list[partition]) != NULL) |
1607 | finish_expr (tab, ptr->value, false); | |
1608 | ||
1609 | if (clear_bit) | |
1610 | bitmap_clear_bit (tab->partition_in_use, partition); | |
1611 | } | |
1612 | ||
1613 | ||
61ada8ae | 1614 | /* This function kills all expressions in TAB which are dependent on virtual |
6de9cd9a DN |
1615 | DEFs. CLEAR_BIT determines whether partition_in_use gets cleared. */ |
1616 | ||
1617 | static inline void | |
1618 | kill_virtual_exprs (temp_expr_table_p tab, bool clear_bit) | |
1619 | { | |
1620 | kill_expr (tab, VIRTUAL_PARTITION (tab), clear_bit); | |
1621 | } | |
1622 | ||
1623 | ||
1624 | /* This function processes basic block BB, and looks for variables which can | |
1625 | be replaced by their expressions. Results are stored in TAB. */ | |
1626 | ||
1627 | static void | |
1628 | find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb) | |
1629 | { | |
1630 | block_stmt_iterator bsi; | |
1631 | tree stmt, def; | |
1632 | stmt_ann_t ann; | |
4c124b4c | 1633 | int partition; |
6de9cd9a DN |
1634 | var_map map = tab->map; |
1635 | value_expr_p p; | |
4c124b4c | 1636 | ssa_op_iter iter; |
6de9cd9a DN |
1637 | |
1638 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1639 | { | |
1640 | stmt = bsi_stmt (bsi); | |
1641 | ann = stmt_ann (stmt); | |
1642 | ||
1643 | /* Determine if this stmt finishes an existing expression. */ | |
4c124b4c | 1644 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1645 | { |
6de9cd9a DN |
1646 | if (tab->version_info[SSA_NAME_VERSION (def)]) |
1647 | { | |
3b6616dd SB |
1648 | bool same_root_var = false; |
1649 | tree def2; | |
1650 | ssa_op_iter iter2; | |
1651 | ||
1652 | /* See if the root variables are the same. If they are, we | |
1653 | do not want to do the replacement to avoid problems with | |
1654 | code size, see PR tree-optimization/17549. */ | |
1655 | FOR_EACH_SSA_TREE_OPERAND (def2, stmt, iter2, SSA_OP_DEF) | |
1656 | if (SSA_NAME_VAR (def) == SSA_NAME_VAR (def2)) | |
1657 | { | |
1658 | same_root_var = true; | |
1659 | break; | |
1660 | } | |
1661 | ||
1662 | /* Mark expression as replaceable unless stmt is volatile | |
1663 | or DEF sets the same root variable as STMT. */ | |
1664 | if (!ann->has_volatile_ops && !same_root_var) | |
6de9cd9a DN |
1665 | mark_replaceable (tab, def); |
1666 | else | |
1667 | finish_expr (tab, SSA_NAME_VERSION (def), false); | |
1668 | } | |
1669 | } | |
1670 | ||
1671 | /* Next, see if this stmt kills off an active expression. */ | |
4c124b4c | 1672 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF) |
6de9cd9a | 1673 | { |
6de9cd9a DN |
1674 | partition = var_to_partition (map, def); |
1675 | if (partition != NO_PARTITION && tab->partition_dep_list[partition]) | |
1676 | kill_expr (tab, partition, true); | |
1677 | } | |
1678 | ||
1679 | /* Now see if we are creating a new expression or not. */ | |
1680 | if (!ann->has_volatile_ops) | |
1681 | check_replaceable (tab, stmt); | |
1682 | ||
61ada8ae | 1683 | /* Free any unused dependency lists. */ |
6de9cd9a DN |
1684 | while ((p = tab->pending_dependence)) |
1685 | { | |
1686 | tab->pending_dependence = p->next; | |
1687 | free_value_expr (tab, p); | |
1688 | } | |
1689 | ||
a32b97a2 BB |
1690 | /* A V_MAY_DEF kills any expression using a virtual operand. */ |
1691 | if (NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann)) > 0) | |
1692 | kill_virtual_exprs (tab, true); | |
1693 | ||
1694 | /* A V_MUST_DEF kills any expression using a virtual operand. */ | |
1695 | if (NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann)) > 0) | |
6de9cd9a DN |
1696 | kill_virtual_exprs (tab, true); |
1697 | } | |
1698 | } | |
1699 | ||
1700 | ||
1701 | /* This function is the driver routine for replacement of temporary expressions | |
1702 | in the SSA->normal phase, operating on MAP. If there are replaceable | |
1703 | expressions, a table is returned which maps SSA versions to the | |
1704 | expressions they should be replaced with. A NULL_TREE indicates no | |
1705 | replacement should take place. If there are no replacements at all, | |
1706 | NULL is returned by the function, otherwise an expression vector indexed | |
1707 | by SSA_NAME version numbers. */ | |
1708 | ||
1709 | static tree * | |
1710 | find_replaceable_exprs (var_map map) | |
1711 | { | |
1712 | basic_block bb; | |
3cd8c58a | 1713 | unsigned i; |
6de9cd9a DN |
1714 | temp_expr_table_p table; |
1715 | tree *ret; | |
1716 | ||
1717 | table = new_temp_expr_table (map); | |
1718 | FOR_EACH_BB (bb) | |
1719 | { | |
87c476a2 ZD |
1720 | bitmap_iterator bi; |
1721 | ||
6de9cd9a | 1722 | find_replaceable_in_bb (table, bb); |
87c476a2 | 1723 | EXECUTE_IF_SET_IN_BITMAP ((table->partition_in_use), 0, i, bi) |
6de9cd9a DN |
1724 | { |
1725 | kill_expr (table, i, false); | |
87c476a2 | 1726 | } |
6de9cd9a DN |
1727 | } |
1728 | ||
1729 | ret = free_temp_expr_table (table); | |
1730 | return ret; | |
1731 | } | |
1732 | ||
1733 | ||
1734 | /* Dump TER expression table EXPR to file F. */ | |
1735 | ||
1736 | static void | |
1737 | dump_replaceable_exprs (FILE *f, tree *expr) | |
1738 | { | |
1739 | tree stmt, var; | |
1740 | int x; | |
1741 | fprintf (f, "\nReplacing Expressions\n"); | |
95a3742c | 1742 | for (x = 0; x < (int)num_ssa_names + 1; x++) |
6de9cd9a DN |
1743 | if (expr[x]) |
1744 | { | |
1745 | stmt = expr[x]; | |
1746 | var = DEF_OP (STMT_DEF_OPS (stmt), 0); | |
1747 | print_generic_expr (f, var, TDF_SLIM); | |
1748 | fprintf (f, " replace with --> "); | |
1749 | print_generic_expr (f, TREE_OPERAND (stmt, 1), TDF_SLIM); | |
1750 | fprintf (f, "\n"); | |
1751 | } | |
1752 | fprintf (f, "\n"); | |
1753 | } | |
1754 | ||
1755 | ||
1756 | /* Helper function for discover_nonconstant_array_refs. | |
1757 | Look for ARRAY_REF nodes with non-constant indexes and mark them | |
1758 | addressable. */ | |
1759 | ||
1760 | static tree | |
1761 | discover_nonconstant_array_refs_r (tree * tp, int *walk_subtrees, | |
1762 | void *data ATTRIBUTE_UNUSED) | |
1763 | { | |
1764 | tree t = *tp; | |
1765 | ||
6615c446 | 1766 | if (IS_TYPE_OR_DECL_P (t)) |
6de9cd9a | 1767 | *walk_subtrees = 0; |
350fae66 | 1768 | else if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) |
6de9cd9a | 1769 | { |
44de5aeb | 1770 | while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) |
8f44bc38 RK |
1771 | && is_gimple_min_invariant (TREE_OPERAND (t, 1)) |
1772 | && (!TREE_OPERAND (t, 2) | |
1773 | || is_gimple_min_invariant (TREE_OPERAND (t, 2)))) | |
6de9cd9a | 1774 | || (TREE_CODE (t) == COMPONENT_REF |
8f44bc38 RK |
1775 | && (!TREE_OPERAND (t,2) |
1776 | || is_gimple_min_invariant (TREE_OPERAND (t, 2)))) | |
1777 | || TREE_CODE (t) == BIT_FIELD_REF | |
1778 | || TREE_CODE (t) == REALPART_EXPR | |
1779 | || TREE_CODE (t) == IMAGPART_EXPR | |
1780 | || TREE_CODE (t) == VIEW_CONVERT_EXPR | |
1781 | || TREE_CODE (t) == NOP_EXPR | |
1782 | || TREE_CODE (t) == CONVERT_EXPR) | |
6de9cd9a DN |
1783 | t = TREE_OPERAND (t, 0); |
1784 | ||
44de5aeb | 1785 | if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) |
6de9cd9a DN |
1786 | { |
1787 | t = get_base_address (t); | |
1788 | if (t && DECL_P (t)) | |
1789 | TREE_ADDRESSABLE (t) = 1; | |
1790 | } | |
1791 | ||
1792 | *walk_subtrees = 0; | |
1793 | } | |
1794 | ||
1795 | return NULL_TREE; | |
1796 | } | |
1797 | ||
1798 | ||
1799 | /* RTL expansion is not able to compile array references with variable | |
1800 | offsets for arrays stored in single register. Discover such | |
1801 | expressions and mark variables as addressable to avoid this | |
1802 | scenario. */ | |
1803 | ||
1804 | static void | |
1805 | discover_nonconstant_array_refs (void) | |
1806 | { | |
1807 | basic_block bb; | |
1808 | block_stmt_iterator bsi; | |
1809 | ||
1810 | FOR_EACH_BB (bb) | |
1811 | { | |
1812 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1813 | walk_tree (bsi_stmt_ptr (bsi), discover_nonconstant_array_refs_r, | |
1814 | NULL , NULL); | |
1815 | } | |
1816 | } | |
1817 | ||
1818 | ||
1819 | /* This function will rewrite the current program using the variable mapping | |
1820 | found in MAP. If the replacement vector VALUES is provided, any | |
1821 | occurrences of partitions with non-null entries in the vector will be | |
1822 | replaced with the expression in the vector instead of its mapped | |
1823 | variable. */ | |
1824 | ||
1825 | static void | |
1826 | rewrite_trees (var_map map, tree *values) | |
1827 | { | |
1828 | elim_graph g; | |
1829 | basic_block bb; | |
1830 | block_stmt_iterator si; | |
1831 | edge e; | |
1832 | tree phi; | |
1833 | bool changed; | |
1834 | ||
1835 | #ifdef ENABLE_CHECKING | |
1836 | /* Search for PHIs where the destination has no partition, but one | |
1837 | or more arguments has a partition. This should not happen and can | |
1838 | create incorrect code. */ | |
1839 | FOR_EACH_BB (bb) | |
1840 | { | |
1841 | tree phi; | |
1842 | ||
17192884 | 1843 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
1844 | { |
1845 | tree T0 = var_to_partition_to_var (map, PHI_RESULT (phi)); | |
1846 | ||
1847 | if (T0 == NULL_TREE) | |
1848 | { | |
1849 | int i; | |
1850 | ||
1851 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
1852 | { | |
1853 | tree arg = PHI_ARG_DEF (phi, i); | |
1854 | ||
1855 | if (TREE_CODE (arg) == SSA_NAME | |
1856 | && var_to_partition (map, arg) != NO_PARTITION) | |
1857 | { | |
1858 | fprintf (stderr, "Argument of PHI is in a partition :("); | |
1859 | print_generic_expr (stderr, arg, TDF_SLIM); | |
1860 | fprintf (stderr, "), but the result is not :"); | |
1861 | print_generic_stmt (stderr, phi, TDF_SLIM); | |
1e128c5f | 1862 | internal_error ("SSA corruption"); |
6de9cd9a DN |
1863 | } |
1864 | } | |
1865 | } | |
1866 | } | |
1867 | } | |
1868 | #endif | |
1869 | ||
1870 | /* Replace PHI nodes with any required copies. */ | |
1871 | g = new_elim_graph (map->num_partitions); | |
1872 | g->map = map; | |
1873 | FOR_EACH_BB (bb) | |
1874 | { | |
1875 | for (si = bsi_start (bb); !bsi_end_p (si); ) | |
1876 | { | |
4c124b4c | 1877 | size_t num_uses, num_defs; |
6de9cd9a DN |
1878 | use_optype uses; |
1879 | def_optype defs; | |
1880 | tree stmt = bsi_stmt (si); | |
d00ad49b | 1881 | use_operand_p use_p; |
4c124b4c | 1882 | def_operand_p def_p; |
6de9cd9a DN |
1883 | int remove = 0, is_copy = 0; |
1884 | stmt_ann_t ann; | |
4c124b4c | 1885 | ssa_op_iter iter; |
6de9cd9a | 1886 | |
6de9cd9a DN |
1887 | ann = stmt_ann (stmt); |
1888 | changed = false; | |
1889 | ||
1890 | if (TREE_CODE (stmt) == MODIFY_EXPR | |
1891 | && (TREE_CODE (TREE_OPERAND (stmt, 1)) == SSA_NAME)) | |
1892 | is_copy = 1; | |
1893 | ||
1894 | uses = USE_OPS (ann); | |
1895 | num_uses = NUM_USES (uses); | |
4c124b4c | 1896 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1897 | { |
d00ad49b | 1898 | if (replace_use_variable (map, use_p, values)) |
6de9cd9a DN |
1899 | changed = true; |
1900 | } | |
1901 | ||
1902 | defs = DEF_OPS (ann); | |
1903 | num_defs = NUM_DEFS (defs); | |
1904 | ||
1905 | /* Mark this stmt for removal if it is the list of replaceable | |
1906 | expressions. */ | |
1907 | if (values && num_defs == 1) | |
1908 | { | |
1909 | tree def = DEF_OP (defs, 0); | |
1910 | tree val; | |
1911 | val = values[SSA_NAME_VERSION (def)]; | |
1912 | if (val) | |
1913 | remove = 1; | |
1914 | } | |
1915 | if (!remove) | |
1916 | { | |
4c124b4c | 1917 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_DEF) |
6de9cd9a | 1918 | { |
d00ad49b | 1919 | if (replace_def_variable (map, def_p, NULL)) |
6de9cd9a DN |
1920 | changed = true; |
1921 | ||
1922 | /* If both SSA_NAMEs coalesce to the same variable, | |
1923 | mark the now redundant copy for removal. */ | |
1924 | if (is_copy | |
1925 | && num_uses == 1 | |
d00ad49b | 1926 | && (DEF_FROM_PTR (def_p) == USE_OP (uses, 0))) |
6de9cd9a DN |
1927 | remove = 1; |
1928 | } | |
6de9cd9a DN |
1929 | } |
1930 | ||
1931 | /* Remove any stmts marked for removal. */ | |
1932 | if (remove) | |
1933 | bsi_remove (&si); | |
1934 | else | |
1935 | bsi_next (&si); | |
1936 | } | |
1937 | ||
1938 | phi = phi_nodes (bb); | |
1939 | if (phi) | |
1940 | { | |
628f6a4e BE |
1941 | edge_iterator ei; |
1942 | FOR_EACH_EDGE (e, ei, bb->preds) | |
41f683ef | 1943 | eliminate_phi (e, g); |
6de9cd9a DN |
1944 | } |
1945 | } | |
1946 | ||
1947 | delete_elim_graph (g); | |
edfaf675 AM |
1948 | } |
1949 | ||
1950 | ||
1951 | /* These are the local work structures used to determine the best place to | |
1952 | insert the copies that were placed on edges by the SSA->normal pass.. */ | |
1953 | static varray_type edge_leader = NULL; | |
1954 | static varray_type GTY(()) stmt_list = NULL; | |
1955 | static bitmap leader_has_match = NULL; | |
1956 | static edge leader_match = NULL; | |
1957 | ||
1958 | ||
1959 | /* Pass this function to make_forwarder_block so that all the edges with | |
1960 | matching PENDING_STMT lists to 'curr_stmt_list' get redirected. */ | |
1961 | static bool | |
1962 | same_stmt_list_p (edge e) | |
1963 | { | |
1964 | return (e->aux == (PTR) leader_match) ? true : false; | |
1965 | } | |
1966 | ||
1967 | ||
1968 | /* Return TRUE if S1 and S2 are equivalent copies. */ | |
1969 | static inline bool | |
1970 | identical_copies_p (tree s1, tree s2) | |
1971 | { | |
1972 | #ifdef ENABLE_CHECKING | |
1973 | gcc_assert (TREE_CODE (s1) == MODIFY_EXPR); | |
1974 | gcc_assert (TREE_CODE (s2) == MODIFY_EXPR); | |
1975 | gcc_assert (DECL_P (TREE_OPERAND (s1, 0))); | |
1976 | gcc_assert (DECL_P (TREE_OPERAND (s2, 0))); | |
1977 | #endif | |
1978 | ||
1979 | if (TREE_OPERAND (s1, 0) != TREE_OPERAND (s2, 0)) | |
1980 | return false; | |
1981 | ||
1982 | s1 = TREE_OPERAND (s1, 1); | |
1983 | s2 = TREE_OPERAND (s2, 1); | |
1984 | ||
1985 | if (s1 != s2) | |
1986 | return false; | |
1987 | ||
1988 | return true; | |
1989 | } | |
1990 | ||
1991 | ||
1992 | /* Compare the PENDING_STMT list for two edges, and return true if the lists | |
1993 | contain the same sequence of copies. */ | |
1994 | ||
1995 | static inline bool | |
1996 | identical_stmt_lists_p (edge e1, edge e2) | |
1997 | { | |
1998 | tree t1 = PENDING_STMT (e1); | |
1999 | tree t2 = PENDING_STMT (e2); | |
2000 | tree_stmt_iterator tsi1, tsi2; | |
2001 | ||
2002 | gcc_assert (TREE_CODE (t1) == STATEMENT_LIST); | |
2003 | gcc_assert (TREE_CODE (t2) == STATEMENT_LIST); | |
2004 | ||
2005 | for (tsi1 = tsi_start (t1), tsi2 = tsi_start (t2); | |
2006 | !tsi_end_p (tsi1) && !tsi_end_p (tsi2); | |
2007 | tsi_next (&tsi1), tsi_next (&tsi2)) | |
2008 | { | |
2009 | if (!identical_copies_p (tsi_stmt (tsi1), tsi_stmt (tsi2))) | |
2010 | break; | |
2011 | } | |
2012 | ||
2013 | if (!tsi_end_p (tsi1) || ! tsi_end_p (tsi2)) | |
2014 | return false; | |
2015 | ||
2016 | return true; | |
2017 | } | |
2018 | ||
2019 | ||
2020 | /* Look at all the incoming edges to block BB, and decide where the best place | |
2021 | to insert the stmts on each edge are, and perform those insertions. Output | |
17008288 | 2022 | any debug information to DEBUG_FILE. */ |
edfaf675 | 2023 | |
b25a2407 | 2024 | static void |
edfaf675 AM |
2025 | analyze_edges_for_bb (basic_block bb, FILE *debug_file) |
2026 | { | |
2027 | edge e; | |
2028 | edge_iterator ei; | |
2029 | int count; | |
2030 | unsigned int x; | |
2031 | bool have_opportunity; | |
2032 | block_stmt_iterator bsi; | |
2033 | tree stmt; | |
2034 | edge single_edge = NULL; | |
2035 | bool is_label; | |
2036 | ||
2037 | count = 0; | |
b00e4c23 AM |
2038 | |
2039 | /* Blocks which contain at least one abnormal edge cannot use | |
2040 | make_forwarder_block. Look for these blocks, and commit any PENDING_STMTs | |
2041 | found on edges in these block. */ | |
2042 | have_opportunity = true; | |
2043 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2044 | if (e->flags & EDGE_ABNORMAL) | |
2045 | { | |
2046 | have_opportunity = false; | |
2047 | break; | |
2048 | } | |
2049 | ||
2050 | if (!have_opportunity) | |
2051 | { | |
2052 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2053 | if (PENDING_STMT (e)) | |
2054 | bsi_commit_one_edge_insert (e, NULL); | |
b25a2407 | 2055 | return; |
b00e4c23 | 2056 | } |
edfaf675 AM |
2057 | /* Find out how many edges there are with interesting pending stmts on them. |
2058 | Commit the stmts on edges we are not interested in. */ | |
2059 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2060 | { | |
2061 | if (PENDING_STMT (e)) | |
2062 | { | |
2063 | gcc_assert (!(e->flags & EDGE_ABNORMAL)); | |
2064 | if (e->flags & EDGE_FALLTHRU) | |
2065 | { | |
2066 | bsi = bsi_start (e->src); | |
2067 | if (!bsi_end_p (bsi)) | |
2068 | { | |
2069 | stmt = bsi_stmt (bsi); | |
2070 | bsi_next (&bsi); | |
2071 | gcc_assert (stmt != NULL_TREE); | |
2072 | is_label = (TREE_CODE (stmt) == LABEL_EXPR); | |
2073 | /* Punt if it has non-label stmts, or isn't local. */ | |
2074 | if (!is_label || DECL_NONLOCAL (TREE_OPERAND (stmt, 0)) | |
2075 | || !bsi_end_p (bsi)) | |
2076 | { | |
2077 | bsi_commit_one_edge_insert (e, NULL); | |
2078 | continue; | |
2079 | } | |
2080 | } | |
2081 | } | |
2082 | single_edge = e; | |
2083 | count++; | |
2084 | } | |
2085 | } | |
2086 | ||
2087 | /* If there aren't at least 2 edges, no sharing will happen. */ | |
2088 | if (count < 2) | |
2089 | { | |
2090 | if (single_edge) | |
2091 | bsi_commit_one_edge_insert (single_edge, NULL); | |
b25a2407 | 2092 | return; |
edfaf675 AM |
2093 | } |
2094 | ||
2095 | /* Ensure that we have empty worklists. */ | |
2096 | if (edge_leader == NULL) | |
2097 | { | |
2098 | VARRAY_EDGE_INIT (edge_leader, 25, "edge_leader"); | |
2099 | VARRAY_TREE_INIT (stmt_list, 25, "stmt_list"); | |
8bdbfff5 | 2100 | leader_has_match = BITMAP_ALLOC (NULL); |
edfaf675 AM |
2101 | } |
2102 | else | |
2103 | { | |
2104 | #ifdef ENABLE_CHECKING | |
2105 | gcc_assert (VARRAY_ACTIVE_SIZE (edge_leader) == 0); | |
2106 | gcc_assert (VARRAY_ACTIVE_SIZE (stmt_list) == 0); | |
65a6f342 | 2107 | gcc_assert (bitmap_empty_p (leader_has_match)); |
edfaf675 AM |
2108 | #endif |
2109 | } | |
2110 | ||
2111 | /* Find the "leader" block for each set of unique stmt lists. Preference is | |
2112 | given to FALLTHRU blocks since they would need a GOTO to arrive at another | |
2113 | block. The leader edge destination is the block which all the other edges | |
2114 | with the same stmt list will be redirected to. */ | |
2115 | have_opportunity = false; | |
2116 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2117 | { | |
2118 | if (PENDING_STMT (e)) | |
2119 | { | |
2120 | bool found = false; | |
2121 | ||
2122 | /* Look for the same stmt list in edge leaders list. */ | |
2123 | for (x = 0; x < VARRAY_ACTIVE_SIZE (edge_leader); x++) | |
2124 | { | |
2125 | edge leader = VARRAY_EDGE (edge_leader, x); | |
2126 | if (identical_stmt_lists_p (leader, e)) | |
2127 | { | |
2128 | /* Give this edge the same stmt list pointer. */ | |
2129 | PENDING_STMT (e) = NULL; | |
2130 | e->aux = leader; | |
2131 | bitmap_set_bit (leader_has_match, x); | |
2132 | have_opportunity = found = true; | |
2133 | break; | |
2134 | } | |
2135 | } | |
2136 | ||
2137 | /* If no similar stmt list, add this edge to the leader list. */ | |
2138 | if (!found) | |
2139 | { | |
2140 | VARRAY_PUSH_EDGE (edge_leader, e); | |
2141 | VARRAY_PUSH_TREE (stmt_list, PENDING_STMT (e)); | |
2142 | } | |
2143 | } | |
2144 | } | |
2145 | ||
2146 | /* If there are no similar lists, just issue the stmts. */ | |
2147 | if (!have_opportunity) | |
2148 | { | |
2149 | for (x = 0; x < VARRAY_ACTIVE_SIZE (edge_leader); x++) | |
2150 | bsi_commit_one_edge_insert (VARRAY_EDGE (edge_leader, x), NULL); | |
2151 | VARRAY_POP_ALL (edge_leader); | |
2152 | VARRAY_POP_ALL (stmt_list); | |
2153 | bitmap_clear (leader_has_match); | |
b25a2407 | 2154 | return; |
edfaf675 AM |
2155 | } |
2156 | ||
2157 | ||
2158 | if (debug_file) | |
2159 | fprintf (debug_file, "\nOpportunities in BB %d for stmt/block reduction:\n", | |
2160 | bb->index); | |
2161 | ||
2162 | ||
2163 | /* For each common list, create a forwarding block and issue the stmt's | |
2164 | in that block. */ | |
2165 | for (x = 0 ; x < VARRAY_ACTIVE_SIZE (edge_leader); x++) | |
2166 | if (bitmap_bit_p (leader_has_match, x)) | |
2167 | { | |
2168 | edge new_edge, leader_edge; | |
2169 | block_stmt_iterator bsi; | |
2170 | tree curr_stmt_list; | |
2171 | ||
2172 | leader_match = leader_edge = VARRAY_EDGE (edge_leader, x); | |
2173 | ||
2174 | /* The tree_* cfg manipulation routines use the PENDING_EDGE field | |
2175 | for various PHI manipulations, so it gets cleared whhen calls are | |
2176 | made to make_forwarder_block(). So make sure the edge is clear, | |
2177 | and use the saved stmt list. */ | |
2178 | PENDING_STMT (leader_edge) = NULL; | |
2179 | leader_edge->aux = leader_edge; | |
2180 | curr_stmt_list = VARRAY_TREE (stmt_list, x); | |
2181 | ||
2182 | new_edge = make_forwarder_block (leader_edge->dest, same_stmt_list_p, | |
2183 | NULL); | |
2184 | bb = new_edge->dest; | |
2185 | if (debug_file) | |
2186 | { | |
2187 | fprintf (debug_file, "Splitting BB %d for Common stmt list. ", | |
2188 | leader_edge->dest->index); | |
2189 | fprintf (debug_file, "Original block is now BB%d.\n", bb->index); | |
2190 | print_generic_stmt (debug_file, curr_stmt_list, TDF_VOPS); | |
2191 | } | |
2192 | ||
2193 | FOR_EACH_EDGE (e, ei, new_edge->src->preds) | |
2194 | { | |
2195 | e->aux = NULL; | |
2196 | if (debug_file) | |
2197 | fprintf (debug_file, " Edge (%d->%d) lands here.\n", | |
2198 | e->src->index, e->dest->index); | |
2199 | } | |
2200 | ||
2201 | bsi = bsi_last (leader_edge->dest); | |
2202 | bsi_insert_after (&bsi, curr_stmt_list, BSI_NEW_STMT); | |
2203 | ||
2204 | leader_match = NULL; | |
2205 | /* We should never get a new block now. */ | |
2206 | } | |
2207 | else | |
2208 | { | |
2209 | e = VARRAY_EDGE (edge_leader, x); | |
2210 | PENDING_STMT (e) = VARRAY_TREE (stmt_list, x); | |
2211 | bsi_commit_one_edge_insert (e, NULL); | |
2212 | } | |
2213 | ||
2214 | ||
2215 | /* Clear the working data structures. */ | |
2216 | VARRAY_POP_ALL (edge_leader); | |
2217 | VARRAY_POP_ALL (stmt_list); | |
2218 | bitmap_clear (leader_has_match); | |
edfaf675 AM |
2219 | } |
2220 | ||
2221 | ||
2222 | /* This function will analyze the insertions which were performed on edges, | |
2223 | and decide whether they should be left on that edge, or whether it is more | |
2224 | efficient to emit some subset of them in a single block. All stmts are | |
2225 | inserted somewhere, and if non-NULL, debug information is printed via | |
2226 | DUMP_FILE. */ | |
2227 | ||
2228 | static void | |
2229 | perform_edge_inserts (FILE *dump_file) | |
2230 | { | |
2231 | basic_block bb; | |
edfaf675 AM |
2232 | |
2233 | if (dump_file) | |
2234 | fprintf(dump_file, "Analyzing Edge Insertions.\n"); | |
2235 | ||
b25a2407 KH |
2236 | /* analyze_edges_for_bb calls make_forwarder_block, which tries to |
2237 | incrementally update the dominator information. Since we don't | |
2238 | need dominator information after this pass, go ahead and free the | |
2239 | dominator information. */ | |
2240 | free_dominance_info (CDI_DOMINATORS); | |
2241 | free_dominance_info (CDI_POST_DOMINATORS); | |
2242 | ||
edfaf675 | 2243 | FOR_EACH_BB (bb) |
b25a2407 | 2244 | analyze_edges_for_bb (bb, dump_file); |
edfaf675 | 2245 | |
b25a2407 | 2246 | analyze_edges_for_bb (EXIT_BLOCK_PTR, dump_file); |
edfaf675 AM |
2247 | |
2248 | /* Clear out any tables which were created. */ | |
2249 | edge_leader = NULL; | |
8bdbfff5 | 2250 | BITMAP_FREE (leader_has_match); |
6de9cd9a | 2251 | |
edfaf675 AM |
2252 | #ifdef ENABLE_CHECKING |
2253 | { | |
2254 | edge_iterator ei; | |
2255 | edge e; | |
2256 | FOR_EACH_BB (bb) | |
2257 | { | |
2258 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2259 | { | |
2260 | if (PENDING_STMT (e)) | |
2261 | error (" Pending stmts not issued on PRED edge (%d, %d)\n", | |
2262 | e->src->index, e->dest->index); | |
2263 | } | |
2264 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2265 | { | |
2266 | if (PENDING_STMT (e)) | |
2267 | error (" Pending stmts not issued on SUCC edge (%d, %d)\n", | |
2268 | e->src->index, e->dest->index); | |
2269 | } | |
2270 | } | |
2271 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) | |
2272 | { | |
2273 | if (PENDING_STMT (e)) | |
2274 | error (" Pending stmts not issued on ENTRY edge (%d, %d)\n", | |
2275 | e->src->index, e->dest->index); | |
2276 | } | |
2277 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) | |
2278 | { | |
2279 | if (PENDING_STMT (e)) | |
2280 | error (" Pending stmts not issued on EXIT edge (%d, %d)\n", | |
2281 | e->src->index, e->dest->index); | |
2282 | } | |
2283 | } | |
2284 | #endif | |
6de9cd9a DN |
2285 | } |
2286 | ||
2287 | ||
2288 | /* Remove the variables specified in MAP from SSA form. Any debug information | |
2289 | is sent to DUMP. FLAGS indicate what options should be used. */ | |
2290 | ||
56b043c8 | 2291 | static void |
6de9cd9a DN |
2292 | remove_ssa_form (FILE *dump, var_map map, int flags) |
2293 | { | |
2294 | tree_live_info_p liveinfo; | |
2295 | basic_block bb; | |
2296 | tree phi, next; | |
2297 | FILE *save; | |
2298 | tree *values = NULL; | |
2299 | ||
2300 | save = dump_file; | |
2301 | dump_file = dump; | |
2302 | ||
2303 | /* If we are not combining temps, don't calculate live ranges for variables | |
2304 | with only one SSA version. */ | |
2305 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
2306 | compact_var_map (map, VARMAP_NO_SINGLE_DEFS); | |
2307 | else | |
2308 | compact_var_map (map, VARMAP_NORMAL); | |
2309 | ||
2310 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2311 | dump_var_map (dump_file, map); | |
2312 | ||
2313 | liveinfo = coalesce_ssa_name (map, flags); | |
2314 | ||
2315 | /* Make sure even single occurrence variables are in the list now. */ | |
2316 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
2317 | compact_var_map (map, VARMAP_NORMAL); | |
2318 | ||
2319 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2320 | { | |
2321 | fprintf (dump_file, "After Coalescing:\n"); | |
2322 | dump_var_map (dump_file, map); | |
2323 | } | |
2324 | ||
2325 | if (flags & SSANORM_PERFORM_TER) | |
2326 | { | |
2327 | values = find_replaceable_exprs (map); | |
2328 | if (values && dump_file && (dump_flags & TDF_DETAILS)) | |
2329 | dump_replaceable_exprs (dump_file, values); | |
2330 | } | |
2331 | ||
2332 | /* Assign real variables to the partitions now. */ | |
2333 | assign_vars (map); | |
2334 | ||
2335 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2336 | { | |
2337 | fprintf (dump_file, "After Root variable replacement:\n"); | |
2338 | dump_var_map (dump_file, map); | |
2339 | } | |
2340 | ||
2341 | if ((flags & SSANORM_COMBINE_TEMPS) && liveinfo) | |
2342 | { | |
2343 | coalesce_vars (map, liveinfo); | |
2344 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2345 | { | |
2346 | fprintf (dump_file, "After variable memory coalescing:\n"); | |
2347 | dump_var_map (dump_file, map); | |
2348 | } | |
2349 | } | |
2350 | ||
2351 | if (liveinfo) | |
2352 | delete_tree_live_info (liveinfo); | |
2353 | ||
2354 | rewrite_trees (map, values); | |
2355 | ||
2356 | if (values) | |
2357 | free (values); | |
2358 | ||
2359 | /* Remove phi nodes which have been translated back to real variables. */ | |
2360 | FOR_EACH_BB (bb) | |
2361 | { | |
2362 | for (phi = phi_nodes (bb); phi; phi = next) | |
2363 | { | |
17192884 | 2364 | next = PHI_CHAIN (phi); |
d19e3ef6 | 2365 | remove_phi_node (phi, NULL_TREE); |
6de9cd9a DN |
2366 | } |
2367 | } | |
2368 | ||
f430bae8 AM |
2369 | /* we no longer maintain the SSA operand cache at this point. */ |
2370 | fini_ssa_operands (); | |
2371 | ||
edfaf675 AM |
2372 | /* If any copies were inserted on edges, analyze and insert them now. */ |
2373 | perform_edge_inserts (dump_file); | |
2374 | ||
6de9cd9a DN |
2375 | dump_file = save; |
2376 | } | |
2377 | ||
06170e1d JL |
2378 | /* Search every PHI node for arguments associated with backedges which |
2379 | we can trivially determine will need a copy (the argument is either | |
2380 | not an SSA_NAME or the argument has a different underlying variable | |
2381 | than the PHI result). | |
2382 | ||
2383 | Insert a copy from the PHI argument to a new destination at the | |
2384 | end of the block with the backedge to the top of the loop. Update | |
2385 | the PHI argument to reference this new destination. */ | |
2386 | ||
2387 | static void | |
2388 | insert_backedge_copies (void) | |
2389 | { | |
2390 | basic_block bb; | |
2391 | ||
2392 | FOR_EACH_BB (bb) | |
2393 | { | |
2394 | tree phi; | |
2395 | ||
2396 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) | |
2397 | { | |
2398 | tree result = PHI_RESULT (phi); | |
2399 | tree result_var; | |
2400 | int i; | |
2401 | ||
2402 | if (!is_gimple_reg (result)) | |
2403 | continue; | |
2404 | ||
2405 | result_var = SSA_NAME_VAR (result); | |
2406 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
2407 | { | |
2408 | tree arg = PHI_ARG_DEF (phi, i); | |
2409 | edge e = PHI_ARG_EDGE (phi, i); | |
2410 | ||
2411 | /* If the argument is not an SSA_NAME, then we will | |
2412 | need a constant initialization. If the argument is | |
2413 | an SSA_NAME with a different underlying variable and | |
2414 | we are not combining temporaries, then we will | |
2415 | need a copy statement. */ | |
2416 | if ((e->flags & EDGE_DFS_BACK) | |
2417 | && (TREE_CODE (arg) != SSA_NAME | |
2418 | || (!flag_tree_combine_temps | |
2419 | && SSA_NAME_VAR (arg) != result_var))) | |
2420 | { | |
2421 | tree stmt, name, last = NULL; | |
2422 | block_stmt_iterator bsi; | |
2423 | ||
2424 | bsi = bsi_last (PHI_ARG_EDGE (phi, i)->src); | |
2425 | if (!bsi_end_p (bsi)) | |
2426 | last = bsi_stmt (bsi); | |
2427 | ||
2428 | /* In theory the only way we ought to get back to the | |
2429 | start of a loop should be with a COND_EXPR or GOTO_EXPR. | |
2430 | However, better safe than sorry. | |
2431 | ||
35fd3193 | 2432 | If the block ends with a control statement or |
06170e1d JL |
2433 | something that might throw, then we have to |
2434 | insert this assignment before the last | |
2435 | statement. Else insert it after the last statement. */ | |
2436 | if (last && stmt_ends_bb_p (last)) | |
2437 | { | |
2438 | /* If the last statement in the block is the definition | |
2439 | site of the PHI argument, then we can't insert | |
2440 | anything after it. */ | |
2441 | if (TREE_CODE (arg) == SSA_NAME | |
2442 | && SSA_NAME_DEF_STMT (arg) == last) | |
2443 | continue; | |
2444 | } | |
2445 | ||
2446 | /* Create a new instance of the underlying | |
2447 | variable of the PHI result. */ | |
2448 | stmt = build (MODIFY_EXPR, TREE_TYPE (result_var), | |
2449 | NULL, PHI_ARG_DEF (phi, i)); | |
2450 | name = make_ssa_name (result_var, stmt); | |
2451 | TREE_OPERAND (stmt, 0) = name; | |
2452 | ||
2453 | /* Insert the new statement into the block and update | |
2454 | the PHI node. */ | |
2455 | if (last && stmt_ends_bb_p (last)) | |
2456 | bsi_insert_before (&bsi, stmt, BSI_NEW_STMT); | |
2457 | else | |
2458 | bsi_insert_after (&bsi, stmt, BSI_NEW_STMT); | |
06170e1d JL |
2459 | SET_PHI_ARG_DEF (phi, i, name); |
2460 | } | |
2461 | } | |
2462 | } | |
2463 | } | |
2464 | } | |
2465 | ||
6de9cd9a DN |
2466 | /* Take the current function out of SSA form, as described in |
2467 | R. Morgan, ``Building an Optimizing Compiler'', | |
2468 | Butterworth-Heinemann, Boston, MA, 1998. pp 176-186. */ | |
2469 | ||
2470 | static void | |
2471 | rewrite_out_of_ssa (void) | |
2472 | { | |
2473 | var_map map; | |
2474 | int var_flags = 0; | |
35bea171 | 2475 | int ssa_flags = 0; |
6de9cd9a | 2476 | |
06170e1d JL |
2477 | /* If elimination of a PHI requires inserting a copy on a backedge, |
2478 | then we will have to split the backedge which has numerous | |
2479 | undesirable performance effects. | |
2480 | ||
2481 | A significant number of such cases can be handled here by inserting | |
2482 | copies into the loop itself. */ | |
2483 | insert_backedge_copies (); | |
2484 | ||
6de9cd9a DN |
2485 | if (!flag_tree_live_range_split) |
2486 | ssa_flags |= SSANORM_COALESCE_PARTITIONS; | |
2487 | ||
2488 | eliminate_virtual_phis (); | |
2489 | ||
2490 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2491 | dump_tree_cfg (dump_file, dump_flags & ~TDF_DETAILS); | |
2492 | ||
2493 | /* We cannot allow unssa to un-gimplify trees before we instrument them. */ | |
2494 | if (flag_tree_ter && !flag_mudflap) | |
2495 | var_flags = SSA_VAR_MAP_REF_COUNT; | |
2496 | ||
2497 | map = create_ssa_var_map (var_flags); | |
2498 | ||
2499 | if (flag_tree_combine_temps) | |
2500 | ssa_flags |= SSANORM_COMBINE_TEMPS; | |
2501 | if (flag_tree_ter && !flag_mudflap) | |
2502 | ssa_flags |= SSANORM_PERFORM_TER; | |
2503 | ||
2504 | remove_ssa_form (dump_file, map, ssa_flags); | |
2505 | ||
2506 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2507 | dump_tree_cfg (dump_file, dump_flags & ~TDF_DETAILS); | |
2508 | ||
6de9cd9a DN |
2509 | /* Flush out flow graph and SSA data. */ |
2510 | delete_var_map (map); | |
2511 | ||
2512 | /* Mark arrays indexed with non-constant indices with TREE_ADDRESSABLE. */ | |
2513 | discover_nonconstant_array_refs (); | |
9885da8e ZD |
2514 | |
2515 | in_ssa_p = false; | |
6de9cd9a DN |
2516 | } |
2517 | ||
2518 | ||
2519 | /* Define the parameters of the out of SSA pass. */ | |
2520 | ||
2521 | struct tree_opt_pass pass_del_ssa = | |
2522 | { | |
2523 | "optimized", /* name */ | |
2524 | NULL, /* gate */ | |
2525 | rewrite_out_of_ssa, /* execute */ | |
2526 | NULL, /* sub */ | |
2527 | NULL, /* next */ | |
2528 | 0, /* static_pass_number */ | |
2529 | TV_TREE_SSA_TO_NORMAL, /* tv_id */ | |
c1b763fa | 2530 | PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */ |
6de9cd9a DN |
2531 | 0, /* properties_provided */ |
2532 | /* ??? If TER is enabled, we also kill gimple. */ | |
2533 | PROP_ssa, /* properties_destroyed */ | |
2534 | TODO_verify_ssa | TODO_verify_flow | |
2535 | | TODO_verify_stmts, /* todo_flags_start */ | |
9f8628ba PB |
2536 | TODO_dump_func | TODO_ggc_collect, /* todo_flags_finish */ |
2537 | 0 /* letter */ | |
6de9cd9a | 2538 | }; |