]>
Commit | Line | Data |
---|---|---|
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 | |
366ccddb KC |
19 | the Free Software Foundation, 51 Franklin Street, Fifth Floor, |
20 | Boston, MA 02110-1301, USA. */ | |
6de9cd9a DN |
21 | |
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
25 | #include "tm.h" | |
26 | #include "tree.h" | |
27 | #include "flags.h" | |
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" | |
6de9cd9a DN |
35 | #include "expr.h" |
36 | #include "function.h" | |
37 | #include "diagnostic.h" | |
38 | #include "bitmap.h" | |
39 | #include "tree-flow.h" | |
eadf906f | 40 | #include "tree-gimple.h" |
6de9cd9a DN |
41 | #include "tree-inline.h" |
42 | #include "varray.h" | |
43 | #include "timevar.h" | |
6de9cd9a DN |
44 | #include "hashtab.h" |
45 | #include "tree-dump.h" | |
46 | #include "tree-ssa-live.h" | |
47 | #include "tree-pass.h" | |
4c714dd4 | 48 | #include "toplev.h" |
6de9cd9a | 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 | |
a9b31c40 KH |
56 | DEF_VEC_I(int); |
57 | DEF_VEC_ALLOC_I(int,heap); | |
58 | ||
6de9cd9a DN |
59 | /* Used to hold all the components required to do SSA PHI elimination. |
60 | The node and pred/succ list is a simple linear list of nodes and | |
61 | edges represented as pairs of nodes. | |
62 | ||
63 | The predecessor and successor list: Nodes are entered in pairs, where | |
64 | [0] ->PRED, [1]->SUCC. All the even indexes in the array represent | |
65 | predecessors, all the odd elements are successors. | |
66 | ||
67 | Rationale: | |
68 | When implemented as bitmaps, very large programs SSA->Normal times were | |
69 | being dominated by clearing the interference graph. | |
70 | ||
71 | Typically this list of edges is extremely small since it only includes | |
72 | PHI results and uses from a single edge which have not coalesced with | |
73 | each other. This means that no virtual PHI nodes are included, and | |
74 | empirical evidence suggests that the number of edges rarely exceed | |
75 | 3, and in a bootstrap of GCC, the maximum size encountered was 7. | |
76 | This also limits the number of possible nodes that are involved to | |
77 | rarely more than 6, and in the bootstrap of gcc, the maximum number | |
78 | of nodes encountered was 12. */ | |
79 | ||
80 | typedef struct _elim_graph { | |
81 | /* Size of the elimination vectors. */ | |
82 | int size; | |
83 | ||
84 | /* List of nodes in the elimination graph. */ | |
bf645d6f | 85 | VEC(tree,heap) *nodes; |
6de9cd9a | 86 | |
9cf737f8 | 87 | /* The predecessor and successor edge list. */ |
a9b31c40 | 88 | VEC(int,heap) *edge_list; |
6de9cd9a DN |
89 | |
90 | /* Visited vector. */ | |
91 | sbitmap visited; | |
92 | ||
93 | /* Stack for visited nodes. */ | |
94 | varray_type stack; | |
95 | ||
96 | /* The variable partition map. */ | |
97 | var_map map; | |
98 | ||
99 | /* Edge being eliminated by this graph. */ | |
100 | edge e; | |
101 | ||
102 | /* List of constant copies to emit. These are pushed on in pairs. */ | |
bf645d6f | 103 | VEC(tree,heap) *const_copies; |
6de9cd9a DN |
104 | } *elim_graph; |
105 | ||
106 | ||
107 | /* Local functions. */ | |
108 | static tree create_temp (tree); | |
109 | static void insert_copy_on_edge (edge, tree, tree); | |
110 | static elim_graph new_elim_graph (int); | |
111 | static inline void delete_elim_graph (elim_graph); | |
112 | static inline void clear_elim_graph (elim_graph); | |
113 | static inline int elim_graph_size (elim_graph); | |
114 | static inline void elim_graph_add_node (elim_graph, tree); | |
115 | static inline void elim_graph_add_edge (elim_graph, int, int); | |
116 | static inline int elim_graph_remove_succ_edge (elim_graph, int); | |
117 | ||
118 | static inline void eliminate_name (elim_graph, tree); | |
41f683ef | 119 | static void eliminate_build (elim_graph, basic_block); |
6de9cd9a DN |
120 | static void elim_forward (elim_graph, int); |
121 | static int elim_unvisited_predecessor (elim_graph, int); | |
122 | static void elim_backward (elim_graph, int); | |
123 | static void elim_create (elim_graph, int); | |
41f683ef | 124 | static void eliminate_phi (edge, elim_graph); |
6de9cd9a DN |
125 | static tree_live_info_p coalesce_ssa_name (var_map, int); |
126 | static void assign_vars (var_map); | |
d00ad49b AM |
127 | static bool replace_use_variable (var_map, use_operand_p, tree *); |
128 | static bool replace_def_variable (var_map, def_operand_p, tree *); | |
6de9cd9a DN |
129 | static void eliminate_virtual_phis (void); |
130 | static void coalesce_abnormal_edges (var_map, conflict_graph, root_var_p); | |
131 | static void print_exprs (FILE *, const char *, tree, const char *, tree, | |
132 | const char *); | |
133 | static void print_exprs_edge (FILE *, edge, const char *, tree, const char *, | |
134 | tree); | |
135 | ||
136 | ||
137 | /* Create a temporary variable based on the type of variable T. Use T's name | |
138 | as the prefix. */ | |
139 | ||
140 | static tree | |
141 | create_temp (tree t) | |
142 | { | |
143 | tree tmp; | |
144 | const char *name = NULL; | |
145 | tree type; | |
146 | ||
147 | if (TREE_CODE (t) == SSA_NAME) | |
148 | t = SSA_NAME_VAR (t); | |
1e128c5f GB |
149 | |
150 | gcc_assert (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == PARM_DECL); | |
6de9cd9a DN |
151 | |
152 | type = TREE_TYPE (t); | |
153 | tmp = DECL_NAME (t); | |
154 | if (tmp) | |
155 | name = IDENTIFIER_POINTER (tmp); | |
156 | ||
157 | if (name == NULL) | |
158 | name = "temp"; | |
159 | tmp = create_tmp_var (type, name); | |
ac3bfd86 | 160 | |
f991abd1 | 161 | if (DECL_DEBUG_EXPR_IS_FROM (t) && DECL_DEBUG_EXPR (t)) |
dad2a933 | 162 | { |
f991abd1 | 163 | SET_DECL_DEBUG_EXPR (tmp, DECL_DEBUG_EXPR (t)); |
dad2a933 RH |
164 | DECL_DEBUG_EXPR_IS_FROM (tmp) = 1; |
165 | } | |
ac3bfd86 | 166 | else if (!DECL_IGNORED_P (t)) |
dad2a933 | 167 | { |
f991abd1 | 168 | SET_DECL_DEBUG_EXPR (tmp, t); |
dad2a933 RH |
169 | DECL_DEBUG_EXPR_IS_FROM (tmp) = 1; |
170 | } | |
6de9cd9a | 171 | DECL_ARTIFICIAL (tmp) = DECL_ARTIFICIAL (t); |
78e0d62b | 172 | DECL_IGNORED_P (tmp) = DECL_IGNORED_P (t); |
6de9cd9a DN |
173 | add_referenced_tmp_var (tmp); |
174 | ||
175 | /* add_referenced_tmp_var will create the annotation and set up some | |
176 | of the flags in the annotation. However, some flags we need to | |
177 | inherit from our original variable. */ | |
178 | var_ann (tmp)->type_mem_tag = var_ann (t)->type_mem_tag; | |
179 | if (is_call_clobbered (t)) | |
180 | mark_call_clobbered (tmp); | |
181 | ||
182 | return tmp; | |
183 | } | |
184 | ||
185 | ||
186 | /* This helper function fill insert a copy from a constant or variable SRC to | |
187 | variable DEST on edge E. */ | |
188 | ||
189 | static void | |
190 | insert_copy_on_edge (edge e, tree dest, tree src) | |
191 | { | |
192 | tree copy; | |
193 | ||
194 | copy = build (MODIFY_EXPR, TREE_TYPE (dest), dest, src); | |
195 | set_is_used (dest); | |
196 | ||
197 | if (TREE_CODE (src) == ADDR_EXPR) | |
198 | src = TREE_OPERAND (src, 0); | |
199 | if (TREE_CODE (src) == VAR_DECL || TREE_CODE (src) == PARM_DECL) | |
200 | set_is_used (src); | |
201 | ||
202 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
203 | { | |
204 | fprintf (dump_file, | |
205 | "Inserting a copy on edge BB%d->BB%d :", | |
206 | e->src->index, | |
207 | e->dest->index); | |
208 | print_generic_expr (dump_file, copy, dump_flags); | |
209 | fprintf (dump_file, "\n"); | |
210 | } | |
211 | ||
212 | bsi_insert_on_edge (e, copy); | |
213 | } | |
214 | ||
215 | ||
216 | /* Create an elimination graph with SIZE nodes and associated data | |
217 | structures. */ | |
218 | ||
219 | static elim_graph | |
220 | new_elim_graph (int size) | |
221 | { | |
222 | elim_graph g = (elim_graph) xmalloc (sizeof (struct _elim_graph)); | |
223 | ||
bf645d6f KH |
224 | g->nodes = VEC_alloc (tree, heap, 30); |
225 | g->const_copies = VEC_alloc (tree, heap, 20); | |
a9b31c40 | 226 | g->edge_list = VEC_alloc (int, heap, 20); |
6de9cd9a DN |
227 | VARRAY_INT_INIT (g->stack, 30, " Elimination Stack"); |
228 | ||
229 | g->visited = sbitmap_alloc (size); | |
230 | ||
231 | return g; | |
232 | } | |
233 | ||
234 | ||
235 | /* Empty elimination graph G. */ | |
236 | ||
237 | static inline void | |
238 | clear_elim_graph (elim_graph g) | |
239 | { | |
bf645d6f | 240 | VEC_truncate (tree, g->nodes, 0); |
a9b31c40 | 241 | VEC_truncate (int, g->edge_list, 0); |
6de9cd9a DN |
242 | } |
243 | ||
244 | ||
245 | /* Delete elimination graph G. */ | |
246 | ||
247 | static inline void | |
248 | delete_elim_graph (elim_graph g) | |
249 | { | |
250 | sbitmap_free (g->visited); | |
a9b31c40 | 251 | VEC_free (int, heap, g->edge_list); |
bf645d6f KH |
252 | VEC_free (tree, heap, g->const_copies); |
253 | VEC_free (tree, heap, g->nodes); | |
6de9cd9a DN |
254 | free (g); |
255 | } | |
256 | ||
257 | ||
258 | /* Return the number of nodes in graph G. */ | |
259 | ||
260 | static inline int | |
261 | elim_graph_size (elim_graph g) | |
262 | { | |
bf645d6f | 263 | return VEC_length (tree, g->nodes); |
6de9cd9a DN |
264 | } |
265 | ||
266 | ||
267 | /* Add NODE to graph G, if it doesn't exist already. */ | |
268 | ||
269 | static inline void | |
270 | elim_graph_add_node (elim_graph g, tree node) | |
271 | { | |
272 | int x; | |
bf645d6f KH |
273 | tree t; |
274 | ||
275 | for (x = 0; VEC_iterate (tree, g->nodes, x, t); x++) | |
276 | if (t == node) | |
6de9cd9a | 277 | return; |
bf645d6f | 278 | VEC_safe_push (tree, heap, g->nodes, node); |
6de9cd9a DN |
279 | } |
280 | ||
281 | ||
282 | /* Add the edge PRED->SUCC to graph G. */ | |
283 | ||
284 | static inline void | |
285 | elim_graph_add_edge (elim_graph g, int pred, int succ) | |
286 | { | |
a9b31c40 KH |
287 | VEC_safe_push (int, heap, g->edge_list, pred); |
288 | VEC_safe_push (int, heap, g->edge_list, succ); | |
6de9cd9a DN |
289 | } |
290 | ||
291 | ||
292 | /* Remove an edge from graph G for which NODE is the predecessor, and | |
293 | return the successor node. -1 is returned if there is no such edge. */ | |
294 | ||
295 | static inline int | |
296 | elim_graph_remove_succ_edge (elim_graph g, int node) | |
297 | { | |
298 | int y; | |
299 | unsigned x; | |
a9b31c40 KH |
300 | for (x = 0; x < VEC_length (int, g->edge_list); x += 2) |
301 | if (VEC_index (int, g->edge_list, x) == node) | |
6de9cd9a | 302 | { |
a9b31c40 KH |
303 | VEC_replace (int, g->edge_list, x, -1); |
304 | y = VEC_index (int, g->edge_list, x + 1); | |
305 | VEC_replace (int, g->edge_list, x + 1, -1); | |
6de9cd9a DN |
306 | return y; |
307 | } | |
308 | return -1; | |
309 | } | |
310 | ||
311 | ||
312 | /* Find all the nodes in GRAPH which are successors to NODE in the | |
313 | edge list. VAR will hold the partition number found. CODE is the | |
314 | code fragment executed for every node found. */ | |
315 | ||
316 | #define FOR_EACH_ELIM_GRAPH_SUCC(GRAPH, NODE, VAR, CODE) \ | |
317 | do { \ | |
318 | unsigned x_; \ | |
319 | int y_; \ | |
a9b31c40 | 320 | for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \ |
6de9cd9a | 321 | { \ |
a9b31c40 | 322 | y_ = VEC_index (int, (GRAPH)->edge_list, x_); \ |
6de9cd9a DN |
323 | if (y_ != (NODE)) \ |
324 | continue; \ | |
a9b31c40 | 325 | (VAR) = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \ |
6de9cd9a DN |
326 | CODE; \ |
327 | } \ | |
328 | } while (0) | |
329 | ||
330 | ||
331 | /* Find all the nodes which are predecessors of NODE in the edge list for | |
332 | GRAPH. VAR will hold the partition number found. CODE is the | |
333 | code fragment executed for every node found. */ | |
334 | ||
335 | #define FOR_EACH_ELIM_GRAPH_PRED(GRAPH, NODE, VAR, CODE) \ | |
336 | do { \ | |
337 | unsigned x_; \ | |
338 | int y_; \ | |
a9b31c40 | 339 | for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \ |
6de9cd9a | 340 | { \ |
a9b31c40 | 341 | y_ = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \ |
6de9cd9a DN |
342 | if (y_ != (NODE)) \ |
343 | continue; \ | |
a9b31c40 | 344 | (VAR) = VEC_index (int, (GRAPH)->edge_list, x_); \ |
6de9cd9a DN |
345 | CODE; \ |
346 | } \ | |
347 | } while (0) | |
348 | ||
349 | ||
350 | /* Add T to elimination graph G. */ | |
351 | ||
352 | static inline void | |
353 | eliminate_name (elim_graph g, tree T) | |
354 | { | |
355 | elim_graph_add_node (g, T); | |
356 | } | |
357 | ||
358 | ||
41f683ef KH |
359 | /* Build elimination graph G for basic block BB on incoming PHI edge |
360 | G->e. */ | |
6de9cd9a DN |
361 | |
362 | static void | |
41f683ef | 363 | eliminate_build (elim_graph g, basic_block B) |
6de9cd9a DN |
364 | { |
365 | tree phi; | |
366 | tree T0, Ti; | |
367 | int p0, pi; | |
368 | ||
369 | clear_elim_graph (g); | |
370 | ||
17192884 | 371 | for (phi = phi_nodes (B); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
372 | { |
373 | T0 = var_to_partition_to_var (g->map, PHI_RESULT (phi)); | |
374 | ||
375 | /* Ignore results which are not in partitions. */ | |
376 | if (T0 == NULL_TREE) | |
377 | continue; | |
378 | ||
41f683ef | 379 | Ti = PHI_ARG_DEF (phi, g->e->dest_idx); |
6de9cd9a DN |
380 | |
381 | /* If this argument is a constant, or a SSA_NAME which is being | |
382 | left in SSA form, just queue a copy to be emitted on this | |
383 | edge. */ | |
384 | if (!phi_ssa_name_p (Ti) | |
385 | || (TREE_CODE (Ti) == SSA_NAME | |
386 | && var_to_partition (g->map, Ti) == NO_PARTITION)) | |
387 | { | |
388 | /* Save constant copies until all other copies have been emitted | |
389 | on this edge. */ | |
bf645d6f KH |
390 | VEC_safe_push (tree, heap, g->const_copies, T0); |
391 | VEC_safe_push (tree, heap, g->const_copies, Ti); | |
6de9cd9a DN |
392 | } |
393 | else | |
394 | { | |
395 | Ti = var_to_partition_to_var (g->map, Ti); | |
396 | if (T0 != Ti) | |
397 | { | |
398 | eliminate_name (g, T0); | |
399 | eliminate_name (g, Ti); | |
400 | p0 = var_to_partition (g->map, T0); | |
401 | pi = var_to_partition (g->map, Ti); | |
402 | elim_graph_add_edge (g, p0, pi); | |
403 | } | |
404 | } | |
405 | } | |
406 | } | |
407 | ||
408 | ||
409 | /* Push successors of T onto the elimination stack for G. */ | |
410 | ||
411 | static void | |
412 | elim_forward (elim_graph g, int T) | |
413 | { | |
414 | int S; | |
415 | SET_BIT (g->visited, T); | |
416 | FOR_EACH_ELIM_GRAPH_SUCC (g, T, S, | |
417 | { | |
418 | if (!TEST_BIT (g->visited, S)) | |
419 | elim_forward (g, S); | |
420 | }); | |
421 | VARRAY_PUSH_INT (g->stack, T); | |
422 | } | |
423 | ||
424 | ||
425 | /* Return 1 if there unvisited predecessors of T in graph G. */ | |
426 | ||
427 | static int | |
428 | elim_unvisited_predecessor (elim_graph g, int T) | |
429 | { | |
430 | int P; | |
431 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
432 | { | |
433 | if (!TEST_BIT (g->visited, P)) | |
434 | return 1; | |
435 | }); | |
436 | return 0; | |
437 | } | |
438 | ||
439 | /* Process predecessors first, and insert a copy. */ | |
440 | ||
441 | static void | |
442 | elim_backward (elim_graph g, int T) | |
443 | { | |
444 | int P; | |
445 | SET_BIT (g->visited, T); | |
446 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
447 | { | |
448 | if (!TEST_BIT (g->visited, P)) | |
449 | { | |
450 | elim_backward (g, P); | |
451 | insert_copy_on_edge (g->e, | |
452 | partition_to_var (g->map, P), | |
453 | partition_to_var (g->map, T)); | |
454 | } | |
455 | }); | |
456 | } | |
457 | ||
458 | /* Insert required copies for T in graph G. Check for a strongly connected | |
459 | region, and create a temporary to break the cycle if one is found. */ | |
460 | ||
461 | static void | |
462 | elim_create (elim_graph g, int T) | |
463 | { | |
464 | tree U; | |
465 | int P, S; | |
466 | ||
467 | if (elim_unvisited_predecessor (g, T)) | |
468 | { | |
469 | U = create_temp (partition_to_var (g->map, T)); | |
470 | insert_copy_on_edge (g->e, U, partition_to_var (g->map, T)); | |
471 | FOR_EACH_ELIM_GRAPH_PRED (g, T, P, | |
472 | { | |
473 | if (!TEST_BIT (g->visited, P)) | |
474 | { | |
475 | elim_backward (g, P); | |
476 | insert_copy_on_edge (g->e, partition_to_var (g->map, P), U); | |
477 | } | |
478 | }); | |
479 | } | |
480 | else | |
481 | { | |
482 | S = elim_graph_remove_succ_edge (g, T); | |
483 | if (S != -1) | |
484 | { | |
485 | SET_BIT (g->visited, T); | |
486 | insert_copy_on_edge (g->e, | |
487 | partition_to_var (g->map, T), | |
488 | partition_to_var (g->map, S)); | |
489 | } | |
490 | } | |
491 | ||
492 | } | |
493 | ||
41f683ef | 494 | /* Eliminate all the phi nodes on edge E in graph G. */ |
6de9cd9a DN |
495 | |
496 | static void | |
41f683ef | 497 | eliminate_phi (edge e, elim_graph g) |
6de9cd9a | 498 | { |
6de9cd9a DN |
499 | int x; |
500 | basic_block B = e->dest; | |
501 | ||
bf645d6f | 502 | gcc_assert (VEC_length (tree, g->const_copies) == 0); |
6de9cd9a | 503 | |
0e61db61 | 504 | /* Abnormal edges already have everything coalesced. */ |
6de9cd9a DN |
505 | if (e->flags & EDGE_ABNORMAL) |
506 | return; | |
507 | ||
6de9cd9a DN |
508 | g->e = e; |
509 | ||
41f683ef | 510 | eliminate_build (g, B); |
6de9cd9a DN |
511 | |
512 | if (elim_graph_size (g) != 0) | |
513 | { | |
bf645d6f KH |
514 | tree var; |
515 | ||
6de9cd9a DN |
516 | sbitmap_zero (g->visited); |
517 | VARRAY_POP_ALL (g->stack); | |
518 | ||
bf645d6f | 519 | for (x = 0; VEC_iterate (tree, g->nodes, x, var); x++) |
6de9cd9a | 520 | { |
6de9cd9a DN |
521 | int p = var_to_partition (g->map, var); |
522 | if (!TEST_BIT (g->visited, p)) | |
523 | elim_forward (g, p); | |
524 | } | |
525 | ||
526 | sbitmap_zero (g->visited); | |
527 | while (VARRAY_ACTIVE_SIZE (g->stack) > 0) | |
528 | { | |
529 | x = VARRAY_TOP_INT (g->stack); | |
530 | VARRAY_POP (g->stack); | |
531 | if (!TEST_BIT (g->visited, x)) | |
532 | elim_create (g, x); | |
533 | } | |
534 | } | |
535 | ||
536 | /* If there are any pending constant copies, issue them now. */ | |
bf645d6f | 537 | while (VEC_length (tree, g->const_copies) > 0) |
6de9cd9a DN |
538 | { |
539 | tree src, dest; | |
bf645d6f KH |
540 | src = VEC_pop (tree, g->const_copies); |
541 | dest = VEC_pop (tree, g->const_copies); | |
6de9cd9a DN |
542 | insert_copy_on_edge (e, dest, src); |
543 | } | |
544 | } | |
545 | ||
546 | ||
547 | /* Shortcut routine to print messages to file F of the form: | |
548 | "STR1 EXPR1 STR2 EXPR2 STR3." */ | |
549 | ||
550 | static void | |
551 | print_exprs (FILE *f, const char *str1, tree expr1, const char *str2, | |
552 | tree expr2, const char *str3) | |
553 | { | |
554 | fprintf (f, "%s", str1); | |
555 | print_generic_expr (f, expr1, TDF_SLIM); | |
556 | fprintf (f, "%s", str2); | |
557 | print_generic_expr (f, expr2, TDF_SLIM); | |
558 | fprintf (f, "%s", str3); | |
559 | } | |
560 | ||
561 | ||
562 | /* Shortcut routine to print abnormal edge messages to file F of the form: | |
563 | "STR1 EXPR1 STR2 EXPR2 across edge E. */ | |
564 | ||
565 | static void | |
566 | print_exprs_edge (FILE *f, edge e, const char *str1, tree expr1, | |
567 | const char *str2, tree expr2) | |
568 | { | |
569 | print_exprs (f, str1, expr1, str2, expr2, " across an abnormal edge"); | |
570 | fprintf (f, " from BB%d->BB%d\n", e->src->index, | |
571 | e->dest->index); | |
572 | } | |
573 | ||
574 | ||
575 | /* Coalesce partitions in MAP which are live across abnormal edges in GRAPH. | |
576 | RV is the root variable groupings of the partitions in MAP. Since code | |
577 | cannot be inserted on these edges, failure to coalesce something across | |
578 | an abnormal edge is an error. */ | |
579 | ||
580 | static void | |
581 | coalesce_abnormal_edges (var_map map, conflict_graph graph, root_var_p rv) | |
582 | { | |
583 | basic_block bb; | |
584 | edge e; | |
585 | tree phi, var, tmp; | |
ff1c708e | 586 | int x, y, z; |
628f6a4e | 587 | edge_iterator ei; |
6de9cd9a DN |
588 | |
589 | /* Code cannot be inserted on abnormal edges. Look for all abnormal | |
590 | edges, and coalesce any PHI results with their arguments across | |
591 | that edge. */ | |
592 | ||
593 | FOR_EACH_BB (bb) | |
628f6a4e | 594 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a | 595 | if (e->dest != EXIT_BLOCK_PTR && e->flags & EDGE_ABNORMAL) |
17192884 | 596 | for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
597 | { |
598 | /* Visit each PHI on the destination side of this abnormal | |
599 | edge, and attempt to coalesce the argument with the result. */ | |
600 | var = PHI_RESULT (phi); | |
601 | x = var_to_partition (map, var); | |
602 | ||
603 | /* Ignore results which are not relevant. */ | |
604 | if (x == NO_PARTITION) | |
605 | continue; | |
606 | ||
be6be258 | 607 | tmp = PHI_ARG_DEF (phi, e->dest_idx); |
1e128c5f | 608 | #ifdef ENABLE_CHECKING |
6de9cd9a DN |
609 | if (!phi_ssa_name_p (tmp)) |
610 | { | |
611 | print_exprs_edge (stderr, e, | |
612 | "\nConstant argument in PHI. Can't insert :", | |
613 | var, " = ", tmp); | |
1e128c5f | 614 | internal_error ("SSA corruption"); |
6de9cd9a | 615 | } |
1e128c5f | 616 | #else |
b49ce401 | 617 | gcc_assert (phi_ssa_name_p (tmp)); |
1e128c5f | 618 | #endif |
6de9cd9a | 619 | y = var_to_partition (map, tmp); |
1e128c5f GB |
620 | gcc_assert (x != NO_PARTITION); |
621 | gcc_assert (y != NO_PARTITION); | |
622 | #ifdef ENABLE_CHECKING | |
6de9cd9a DN |
623 | if (root_var_find (rv, x) != root_var_find (rv, y)) |
624 | { | |
625 | print_exprs_edge (stderr, e, "\nDifferent root vars: ", | |
626 | root_var (rv, root_var_find (rv, x)), | |
627 | " and ", | |
628 | root_var (rv, root_var_find (rv, y))); | |
1e128c5f | 629 | internal_error ("SSA corruption"); |
6de9cd9a | 630 | } |
1e128c5f GB |
631 | #else |
632 | gcc_assert (root_var_find (rv, x) == root_var_find (rv, y)); | |
633 | #endif | |
6de9cd9a DN |
634 | |
635 | if (x != y) | |
636 | { | |
1e128c5f GB |
637 | #ifdef ENABLE_CHECKING |
638 | if (conflict_graph_conflict_p (graph, x, y)) | |
6de9cd9a DN |
639 | { |
640 | print_exprs_edge (stderr, e, "\n Conflict ", | |
641 | partition_to_var (map, x), | |
642 | " and ", partition_to_var (map, y)); | |
1e128c5f | 643 | internal_error ("SSA corruption"); |
6de9cd9a | 644 | } |
1e128c5f GB |
645 | #else |
646 | gcc_assert (!conflict_graph_conflict_p (graph, x, y)); | |
647 | #endif | |
648 | ||
649 | /* Now map the partitions back to their real variables. */ | |
650 | var = partition_to_var (map, x); | |
651 | tmp = partition_to_var (map, y); | |
652 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
653 | { | |
654 | print_exprs_edge (dump_file, e, | |
655 | "ABNORMAL: Coalescing ", | |
656 | var, " and ", tmp); | |
657 | } | |
ff1c708e | 658 | z = var_union (map, var, tmp); |
1e128c5f | 659 | #ifdef ENABLE_CHECKING |
ff1c708e | 660 | if (z == NO_PARTITION) |
1e128c5f GB |
661 | { |
662 | print_exprs_edge (stderr, e, "\nUnable to coalesce", | |
663 | partition_to_var (map, x), " and ", | |
664 | partition_to_var (map, y)); | |
665 | internal_error ("SSA corruption"); | |
666 | } | |
667 | #else | |
ff1c708e | 668 | gcc_assert (z != NO_PARTITION); |
1e128c5f | 669 | #endif |
ff1c708e JL |
670 | gcc_assert (z == x || z == y); |
671 | if (z == x) | |
672 | conflict_graph_merge_regs (graph, x, y); | |
673 | else | |
674 | conflict_graph_merge_regs (graph, y, x); | |
6de9cd9a DN |
675 | } |
676 | } | |
677 | } | |
678 | ||
5a910e43 | 679 | /* Coalesce potential copies via PHI arguments. */ |
6de9cd9a | 680 | |
5a910e43 RH |
681 | static void |
682 | coalesce_phi_operands (var_map map, coalesce_list_p cl) | |
6de9cd9a | 683 | { |
6de9cd9a | 684 | basic_block bb; |
5a910e43 | 685 | tree phi; |
35bea171 | 686 | |
35bea171 | 687 | FOR_EACH_BB (bb) |
6de9cd9a | 688 | { |
35bea171 | 689 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a | 690 | { |
35bea171 KH |
691 | tree res = PHI_RESULT (phi); |
692 | int p = var_to_partition (map, res); | |
5a910e43 RH |
693 | int x; |
694 | ||
35bea171 KH |
695 | if (p == NO_PARTITION) |
696 | continue; | |
5a910e43 RH |
697 | |
698 | for (x = 0; x < PHI_NUM_ARGS (phi); x++) | |
6de9cd9a | 699 | { |
35bea171 KH |
700 | tree arg = PHI_ARG_DEF (phi, x); |
701 | int p2; | |
702 | ||
703 | if (TREE_CODE (arg) != SSA_NAME) | |
6de9cd9a | 704 | continue; |
35bea171 KH |
705 | if (SSA_NAME_VAR (res) != SSA_NAME_VAR (arg)) |
706 | continue; | |
707 | p2 = var_to_partition (map, PHI_ARG_DEF (phi, x)); | |
708 | if (p2 != NO_PARTITION) | |
0bde02b3 JH |
709 | { |
710 | edge e = PHI_ARG_EDGE (phi, x); | |
711 | add_coalesce (cl, p, p2, | |
712 | coalesce_cost (EDGE_FREQUENCY (e), | |
713 | maybe_hot_bb_p (bb), | |
714 | EDGE_CRITICAL_P (e))); | |
715 | } | |
6de9cd9a DN |
716 | } |
717 | } | |
35bea171 | 718 | } |
5a910e43 RH |
719 | } |
720 | ||
721 | /* Coalesce all the result decls together. */ | |
722 | ||
723 | static void | |
724 | coalesce_result_decls (var_map map, coalesce_list_p cl) | |
725 | { | |
726 | unsigned int i, x; | |
727 | tree var = NULL; | |
6de9cd9a | 728 | |
5a910e43 | 729 | for (i = x = 0; x < num_var_partitions (map); x++) |
35bea171 KH |
730 | { |
731 | tree p = partition_to_var (map, x); | |
5a910e43 | 732 | if (TREE_CODE (SSA_NAME_VAR (p)) == RESULT_DECL) |
6de9cd9a | 733 | { |
35bea171 | 734 | if (var == NULL_TREE) |
6de9cd9a | 735 | { |
35bea171 KH |
736 | var = p; |
737 | i = x; | |
6de9cd9a | 738 | } |
35bea171 | 739 | else |
0bde02b3 JH |
740 | add_coalesce (cl, i, x, |
741 | coalesce_cost (EXIT_BLOCK_PTR->frequency, | |
742 | maybe_hot_bb_p (EXIT_BLOCK_PTR), | |
743 | false)); | |
6de9cd9a DN |
744 | } |
745 | } | |
5a910e43 RH |
746 | } |
747 | ||
748 | /* Coalesce matching constraints in asms. */ | |
749 | ||
750 | static void | |
751 | coalesce_asm_operands (var_map map, coalesce_list_p cl) | |
752 | { | |
753 | basic_block bb; | |
754 | ||
755 | FOR_EACH_BB (bb) | |
756 | { | |
757 | block_stmt_iterator bsi; | |
758 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
759 | { | |
760 | tree stmt = bsi_stmt (bsi); | |
761 | unsigned long noutputs, i; | |
762 | tree *outputs, link; | |
763 | ||
764 | if (TREE_CODE (stmt) != ASM_EXPR) | |
765 | continue; | |
766 | ||
767 | noutputs = list_length (ASM_OUTPUTS (stmt)); | |
768 | outputs = (tree *) alloca (noutputs * sizeof (tree)); | |
769 | for (i = 0, link = ASM_OUTPUTS (stmt); link; | |
770 | ++i, link = TREE_CHAIN (link)) | |
771 | outputs[i] = TREE_VALUE (link); | |
772 | ||
773 | for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link)) | |
774 | { | |
775 | const char *constraint | |
776 | = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); | |
777 | tree input = TREE_VALUE (link); | |
778 | char *end; | |
779 | unsigned long match; | |
780 | int p1, p2; | |
781 | ||
782 | if (TREE_CODE (input) != SSA_NAME && !DECL_P (input)) | |
783 | continue; | |
784 | ||
785 | match = strtoul (constraint, &end, 10); | |
786 | if (match >= noutputs || end == constraint) | |
787 | continue; | |
788 | ||
789 | if (TREE_CODE (outputs[match]) != SSA_NAME | |
790 | && !DECL_P (outputs[match])) | |
791 | continue; | |
792 | ||
793 | p1 = var_to_partition (map, outputs[match]); | |
794 | if (p1 == NO_PARTITION) | |
795 | continue; | |
796 | p2 = var_to_partition (map, input); | |
797 | if (p2 == NO_PARTITION) | |
798 | continue; | |
799 | ||
800 | add_coalesce (cl, p1, p2, coalesce_cost (REG_BR_PROB_BASE, | |
801 | maybe_hot_bb_p (bb), | |
802 | false)); | |
803 | } | |
804 | } | |
805 | } | |
806 | } | |
807 | ||
808 | /* Reduce the number of live ranges in MAP. Live range information is | |
809 | returned if FLAGS indicates that we are combining temporaries, otherwise | |
810 | NULL is returned. The only partitions which are associated with actual | |
811 | variables at this point are those which are forced to be coalesced for | |
812 | various reason. (live on entry, live across abnormal edges, etc.). */ | |
813 | ||
814 | static tree_live_info_p | |
815 | coalesce_ssa_name (var_map map, int flags) | |
816 | { | |
817 | unsigned num, x; | |
818 | sbitmap live; | |
819 | root_var_p rv; | |
820 | tree_live_info_p liveinfo; | |
821 | conflict_graph graph; | |
822 | coalesce_list_p cl = NULL; | |
823 | sbitmap_iterator sbi; | |
824 | ||
825 | if (num_var_partitions (map) <= 1) | |
826 | return NULL; | |
827 | ||
828 | liveinfo = calculate_live_on_entry (map); | |
829 | calculate_live_on_exit (liveinfo); | |
830 | rv = root_var_init (map); | |
831 | ||
832 | /* Remove single element variable from the list. */ | |
833 | root_var_compact (rv); | |
834 | ||
835 | cl = create_coalesce_list (map); | |
836 | ||
837 | coalesce_phi_operands (map, cl); | |
838 | coalesce_result_decls (map, cl); | |
839 | coalesce_asm_operands (map, cl); | |
6de9cd9a DN |
840 | |
841 | /* Build a conflict graph. */ | |
842 | graph = build_tree_conflict_graph (liveinfo, rv, cl); | |
843 | ||
844 | if (cl) | |
845 | { | |
846 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
847 | { | |
848 | fprintf (dump_file, "Before sorting:\n"); | |
849 | dump_coalesce_list (dump_file, cl); | |
850 | } | |
851 | ||
852 | sort_coalesce_list (cl); | |
853 | ||
854 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
855 | { | |
856 | fprintf (dump_file, "\nAfter sorting:\n"); | |
857 | dump_coalesce_list (dump_file, cl); | |
858 | } | |
859 | } | |
860 | ||
861 | /* Put the single element variables back in. */ | |
862 | root_var_decompact (rv); | |
863 | ||
864 | /* First, coalesce all live on entry variables to their root variable. | |
9cf737f8 | 865 | This will ensure the first use is coming from the correct location. */ |
6de9cd9a | 866 | |
5a910e43 RH |
867 | num = num_var_partitions (map); |
868 | live = sbitmap_alloc (num); | |
6de9cd9a DN |
869 | sbitmap_zero (live); |
870 | ||
871 | /* Set 'live' vector to indicate live on entry partitions. */ | |
6de9cd9a DN |
872 | for (x = 0 ; x < num; x++) |
873 | { | |
5a910e43 | 874 | tree var = partition_to_var (map, x); |
6de9cd9a DN |
875 | if (default_def (SSA_NAME_VAR (var)) == var) |
876 | SET_BIT (live, x); | |
877 | } | |
878 | ||
879 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
880 | { | |
881 | delete_tree_live_info (liveinfo); | |
882 | liveinfo = NULL; | |
883 | } | |
884 | ||
885 | /* Assign root variable as partition representative for each live on entry | |
886 | partition. */ | |
b6e7e9af | 887 | EXECUTE_IF_SET_IN_SBITMAP (live, 0, x, sbi) |
6de9cd9a | 888 | { |
5a910e43 RH |
889 | tree var = root_var (rv, root_var_find (rv, x)); |
890 | var_ann_t ann = var_ann (var); | |
6de9cd9a DN |
891 | /* If these aren't already coalesced... */ |
892 | if (partition_to_var (map, x) != var) | |
893 | { | |
1e128c5f GB |
894 | /* This root variable should have not already been assigned |
895 | to another partition which is not coalesced with this one. */ | |
896 | gcc_assert (!ann->out_of_ssa_tag); | |
6de9cd9a DN |
897 | |
898 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
899 | { | |
900 | print_exprs (dump_file, "Must coalesce ", | |
901 | partition_to_var (map, x), | |
902 | " with the root variable ", var, ".\n"); | |
903 | } | |
904 | ||
905 | change_partition_var (map, var, x); | |
906 | } | |
b6e7e9af | 907 | } |
6de9cd9a DN |
908 | |
909 | sbitmap_free (live); | |
910 | ||
911 | /* Coalesce partitions live across abnormal edges. */ | |
912 | coalesce_abnormal_edges (map, graph, rv); | |
913 | ||
914 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
915 | dump_var_map (dump_file, map); | |
916 | ||
917 | /* Coalesce partitions. */ | |
35bea171 KH |
918 | coalesce_tpa_members (rv, graph, map, cl, |
919 | ((dump_flags & TDF_DETAILS) ? dump_file | |
920 | : NULL)); | |
6de9cd9a | 921 | |
6de9cd9a | 922 | if (flags & SSANORM_COALESCE_PARTITIONS) |
35bea171 KH |
923 | coalesce_tpa_members (rv, graph, map, NULL, |
924 | ((dump_flags & TDF_DETAILS) ? dump_file | |
925 | : NULL)); | |
6de9cd9a DN |
926 | if (cl) |
927 | delete_coalesce_list (cl); | |
928 | root_var_delete (rv); | |
929 | conflict_graph_delete (graph); | |
930 | ||
931 | return liveinfo; | |
932 | } | |
933 | ||
934 | ||
935 | /* Take the ssa-name var_map MAP, and assign real variables to each | |
936 | partition. */ | |
937 | ||
938 | static void | |
939 | assign_vars (var_map map) | |
940 | { | |
941 | int x, i, num, rep; | |
942 | tree t, var; | |
943 | var_ann_t ann; | |
944 | root_var_p rv; | |
945 | ||
946 | rv = root_var_init (map); | |
947 | if (!rv) | |
948 | return; | |
949 | ||
950 | /* Coalescing may already have forced some partitions to their root | |
951 | variable. Find these and tag them. */ | |
952 | ||
953 | num = num_var_partitions (map); | |
954 | for (x = 0; x < num; x++) | |
955 | { | |
956 | var = partition_to_var (map, x); | |
957 | if (TREE_CODE (var) != SSA_NAME) | |
958 | { | |
959 | /* Coalescing will already have verified that more than one | |
960 | partition doesn't have the same root variable. Simply marked | |
961 | the variable as assigned. */ | |
962 | ann = var_ann (var); | |
963 | ann->out_of_ssa_tag = 1; | |
964 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
965 | { | |
966 | fprintf (dump_file, "partition %d has variable ", x); | |
967 | print_generic_expr (dump_file, var, TDF_SLIM); | |
968 | fprintf (dump_file, " assigned to it.\n"); | |
969 | } | |
970 | ||
971 | } | |
972 | } | |
973 | ||
974 | num = root_var_num (rv); | |
975 | for (x = 0; x < num; x++) | |
976 | { | |
977 | var = root_var (rv, x); | |
978 | ann = var_ann (var); | |
979 | for (i = root_var_first_partition (rv, x); | |
980 | i != ROOT_VAR_NONE; | |
981 | i = root_var_next_partition (rv, i)) | |
982 | { | |
983 | t = partition_to_var (map, i); | |
984 | ||
985 | if (t == var || TREE_CODE (t) != SSA_NAME) | |
986 | continue; | |
987 | ||
988 | rep = var_to_partition (map, t); | |
989 | ||
990 | if (!ann->out_of_ssa_tag) | |
991 | { | |
992 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
993 | print_exprs (dump_file, "", t, " --> ", var, "\n"); | |
994 | change_partition_var (map, var, rep); | |
995 | continue; | |
996 | } | |
997 | ||
998 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
999 | print_exprs (dump_file, "", t, " not coalesced with ", var, | |
1000 | ""); | |
1001 | ||
1002 | var = create_temp (t); | |
1003 | change_partition_var (map, var, rep); | |
1004 | ann = var_ann (var); | |
1005 | ||
1006 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1007 | { | |
1008 | fprintf (dump_file, " --> New temp: '"); | |
1009 | print_generic_expr (dump_file, var, TDF_SLIM); | |
1010 | fprintf (dump_file, "'\n"); | |
1011 | } | |
1012 | } | |
1013 | } | |
1014 | ||
1015 | root_var_delete (rv); | |
1016 | } | |
1017 | ||
1018 | ||
d00ad49b AM |
1019 | /* Replace use operand P with whatever variable it has been rewritten to based |
1020 | on the partitions in MAP. EXPR is an optional expression vector over SSA | |
1021 | versions which is used to replace P with an expression instead of a variable. | |
6de9cd9a DN |
1022 | If the stmt is changed, return true. */ |
1023 | ||
1024 | static inline bool | |
d00ad49b | 1025 | replace_use_variable (var_map map, use_operand_p p, tree *expr) |
6de9cd9a DN |
1026 | { |
1027 | tree new_var; | |
d00ad49b | 1028 | tree var = USE_FROM_PTR (p); |
6de9cd9a DN |
1029 | |
1030 | /* Check if we are replacing this variable with an expression. */ | |
1031 | if (expr) | |
1032 | { | |
d00ad49b | 1033 | int version = SSA_NAME_VERSION (var); |
6de9cd9a DN |
1034 | if (expr[version]) |
1035 | { | |
1036 | tree new_expr = TREE_OPERAND (expr[version], 1); | |
d00ad49b | 1037 | SET_USE (p, new_expr); |
6de9cd9a DN |
1038 | /* Clear the stmt's RHS, or GC might bite us. */ |
1039 | TREE_OPERAND (expr[version], 1) = NULL_TREE; | |
1040 | return true; | |
1041 | } | |
1042 | } | |
1043 | ||
1044 | new_var = var_to_partition_to_var (map, var); | |
1045 | if (new_var) | |
1046 | { | |
d00ad49b AM |
1047 | SET_USE (p, new_var); |
1048 | set_is_used (new_var); | |
1049 | return true; | |
1050 | } | |
1051 | return false; | |
1052 | } | |
1053 | ||
1054 | ||
1055 | /* Replace def operand DEF_P with whatever variable it has been rewritten to | |
1056 | based on the partitions in MAP. EXPR is an optional expression vector over | |
1057 | SSA versions which is used to replace DEF_P with an expression instead of a | |
1058 | variable. If the stmt is changed, return true. */ | |
1059 | ||
1060 | static inline bool | |
1061 | replace_def_variable (var_map map, def_operand_p def_p, tree *expr) | |
1062 | { | |
1063 | tree new_var; | |
1064 | tree var = DEF_FROM_PTR (def_p); | |
1065 | ||
1066 | /* Check if we are replacing this variable with an expression. */ | |
1067 | if (expr) | |
1068 | { | |
1069 | int version = SSA_NAME_VERSION (var); | |
1070 | if (expr[version]) | |
1071 | { | |
1072 | tree new_expr = TREE_OPERAND (expr[version], 1); | |
1073 | SET_DEF (def_p, new_expr); | |
1074 | /* Clear the stmt's RHS, or GC might bite us. */ | |
1075 | TREE_OPERAND (expr[version], 1) = NULL_TREE; | |
1076 | return true; | |
1077 | } | |
1078 | } | |
1079 | ||
1080 | new_var = var_to_partition_to_var (map, var); | |
1081 | if (new_var) | |
1082 | { | |
1083 | SET_DEF (def_p, new_var); | |
6de9cd9a DN |
1084 | set_is_used (new_var); |
1085 | return true; | |
1086 | } | |
1087 | return false; | |
1088 | } | |
1089 | ||
1090 | ||
1091 | /* Remove any PHI node which is a virtual PHI. */ | |
1092 | ||
1093 | static void | |
1094 | eliminate_virtual_phis (void) | |
1095 | { | |
1096 | basic_block bb; | |
1097 | tree phi, next; | |
1098 | ||
1099 | FOR_EACH_BB (bb) | |
1100 | { | |
1101 | for (phi = phi_nodes (bb); phi; phi = next) | |
1102 | { | |
17192884 | 1103 | next = PHI_CHAIN (phi); |
6de9cd9a DN |
1104 | if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi)))) |
1105 | { | |
1106 | #ifdef ENABLE_CHECKING | |
1107 | int i; | |
1108 | /* There should be no arguments of this PHI which are in | |
1109 | the partition list, or we get incorrect results. */ | |
1110 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
1111 | { | |
1112 | tree arg = PHI_ARG_DEF (phi, i); | |
1113 | if (TREE_CODE (arg) == SSA_NAME | |
1114 | && is_gimple_reg (SSA_NAME_VAR (arg))) | |
1115 | { | |
1116 | fprintf (stderr, "Argument of PHI is not virtual ("); | |
1117 | print_generic_expr (stderr, arg, TDF_SLIM); | |
1118 | fprintf (stderr, "), but the result is :"); | |
1119 | print_generic_stmt (stderr, phi, TDF_SLIM); | |
1e128c5f | 1120 | internal_error ("SSA corruption"); |
6de9cd9a DN |
1121 | } |
1122 | } | |
1123 | #endif | |
d19e3ef6 | 1124 | remove_phi_node (phi, NULL_TREE); |
6de9cd9a DN |
1125 | } |
1126 | } | |
1127 | } | |
1128 | } | |
1129 | ||
1130 | ||
1131 | /* This routine will coalesce variables in MAP of the same type which do not | |
1132 | interfere with each other. LIVEINFO is the live range info for variables | |
1133 | of interest. This will both reduce the memory footprint of the stack, and | |
1134 | allow us to coalesce together local copies of globals and scalarized | |
1135 | component refs. */ | |
1136 | ||
1137 | static void | |
1138 | coalesce_vars (var_map map, tree_live_info_p liveinfo) | |
1139 | { | |
1140 | basic_block bb; | |
1141 | type_var_p tv; | |
1142 | tree var; | |
3cd8c58a | 1143 | unsigned x, p, p2; |
6de9cd9a DN |
1144 | coalesce_list_p cl; |
1145 | conflict_graph graph; | |
1146 | ||
1147 | cl = create_coalesce_list (map); | |
1148 | ||
1149 | /* Merge all the live on entry vectors for coalesced partitions. */ | |
1150 | for (x = 0; x < num_var_partitions (map); x++) | |
1151 | { | |
1152 | var = partition_to_var (map, x); | |
1153 | p = var_to_partition (map, var); | |
1154 | if (p != x) | |
1155 | live_merge_and_clear (liveinfo, p, x); | |
1156 | } | |
1157 | ||
1158 | /* When PHI nodes are turned into copies, the result of each PHI node | |
1159 | becomes live on entry to the block. Mark these now. */ | |
1160 | FOR_EACH_BB (bb) | |
1161 | { | |
1162 | tree phi, arg; | |
3cd8c58a NS |
1163 | unsigned p; |
1164 | ||
17192884 | 1165 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
1166 | { |
1167 | p = var_to_partition (map, PHI_RESULT (phi)); | |
1168 | ||
1169 | /* Skip virtual PHI nodes. */ | |
3cd8c58a | 1170 | if (p == (unsigned)NO_PARTITION) |
6de9cd9a DN |
1171 | continue; |
1172 | ||
1173 | make_live_on_entry (liveinfo, bb, p); | |
1174 | ||
1175 | /* Each argument is a potential copy operation. Add any arguments | |
1176 | which are not coalesced to the result to the coalesce list. */ | |
3cd8c58a | 1177 | for (x = 0; x < (unsigned)PHI_NUM_ARGS (phi); x++) |
6de9cd9a DN |
1178 | { |
1179 | arg = PHI_ARG_DEF (phi, x); | |
1180 | if (!phi_ssa_name_p (arg)) | |
1181 | continue; | |
1182 | p2 = var_to_partition (map, arg); | |
3cd8c58a | 1183 | if (p2 == (unsigned)NO_PARTITION) |
6de9cd9a DN |
1184 | continue; |
1185 | if (p != p2) | |
0bde02b3 JH |
1186 | { |
1187 | edge e = PHI_ARG_EDGE (phi, x); | |
1188 | ||
1189 | add_coalesce (cl, p, p2, | |
1190 | coalesce_cost (EDGE_FREQUENCY (e), | |
1191 | maybe_hot_bb_p (bb), | |
1192 | EDGE_CRITICAL_P (e))); | |
1193 | } | |
6de9cd9a DN |
1194 | } |
1195 | } | |
1196 | } | |
1197 | ||
1198 | ||
1199 | /* Re-calculate live on exit info. */ | |
1200 | calculate_live_on_exit (liveinfo); | |
1201 | ||
1202 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1203 | { | |
1204 | fprintf (dump_file, "Live range info for variable memory coalescing.\n"); | |
1205 | dump_live_info (dump_file, liveinfo, LIVEDUMP_ALL); | |
1206 | ||
1207 | fprintf (dump_file, "Coalesce list from phi nodes:\n"); | |
1208 | dump_coalesce_list (dump_file, cl); | |
1209 | } | |
1210 | ||
1211 | ||
1212 | tv = type_var_init (map); | |
1213 | if (dump_file) | |
1214 | type_var_dump (dump_file, tv); | |
1215 | type_var_compact (tv); | |
1216 | if (dump_file) | |
1217 | type_var_dump (dump_file, tv); | |
1218 | ||
1219 | graph = build_tree_conflict_graph (liveinfo, tv, cl); | |
1220 | ||
1221 | type_var_decompact (tv); | |
1222 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1223 | { | |
1224 | fprintf (dump_file, "type var list now looks like:n"); | |
1225 | type_var_dump (dump_file, tv); | |
1226 | ||
1227 | fprintf (dump_file, "Coalesce list after conflict graph build:\n"); | |
1228 | dump_coalesce_list (dump_file, cl); | |
1229 | } | |
1230 | ||
1231 | sort_coalesce_list (cl); | |
1232 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1233 | { | |
1234 | fprintf (dump_file, "Coalesce list after sorting:\n"); | |
1235 | dump_coalesce_list (dump_file, cl); | |
1236 | } | |
1237 | ||
1238 | coalesce_tpa_members (tv, graph, map, cl, | |
1239 | ((dump_flags & TDF_DETAILS) ? dump_file : NULL)); | |
1240 | ||
1241 | type_var_delete (tv); | |
1242 | delete_coalesce_list (cl); | |
1243 | } | |
1244 | ||
1245 | ||
1246 | /* Temporary Expression Replacement (TER) | |
1247 | ||
1248 | Replace SSA version variables during out-of-ssa with their defining | |
1249 | expression if there is only one use of the variable. | |
1250 | ||
1251 | A pass is made through the function, one block at a time. No cross block | |
1252 | information is tracked. | |
1253 | ||
1254 | Variables which only have one use, and whose defining stmt is considered | |
1255 | a replaceable expression (see check_replaceable) are entered into | |
1256 | consideration by adding a list of dependent partitions to the version_info | |
1257 | vector for that ssa_name_version. This information comes from the partition | |
1258 | mapping for each USE. At the same time, the partition_dep_list vector for | |
1259 | these partitions have this version number entered into their lists. | |
1260 | ||
1261 | When the use of a replaceable ssa_variable is encountered, the dependence | |
1262 | list in version_info[] is moved to the "pending_dependence" list in case | |
1263 | the current expression is also replaceable. (To be determined later in | |
1264 | processing this stmt.) version_info[] for the version is then updated to | |
1265 | point to the defining stmt and the 'replaceable' bit is set. | |
1266 | ||
1267 | Any partition which is defined by a statement 'kills' any expression which | |
1268 | is dependent on this partition. Every ssa version in the partitions' | |
1269 | dependence list is removed from future consideration. | |
1270 | ||
1271 | All virtual references are lumped together. Any expression which is | |
1272 | dependent on any virtual variable (via a VUSE) has a dependence added | |
1273 | to the special partition defined by VIRTUAL_PARTITION. | |
1274 | ||
a32b97a2 BB |
1275 | Whenever a V_MAY_DEF is seen, all expressions dependent this |
1276 | VIRTUAL_PARTITION are removed from consideration. | |
6de9cd9a DN |
1277 | |
1278 | At the end of a basic block, all expression are removed from consideration | |
1279 | in preparation for the next block. | |
1280 | ||
1281 | The end result is a vector over SSA_NAME_VERSION which is passed back to | |
1282 | rewrite_out_of_ssa. As the SSA variables are being rewritten, instead of | |
1283 | replacing the SSA_NAME tree element with the partition it was assigned, | |
1284 | it is replaced with the RHS of the defining expression. */ | |
1285 | ||
1286 | ||
61ada8ae | 1287 | /* Dependency list element. This can contain either a partition index or a |
6de9cd9a DN |
1288 | version number, depending on which list it is in. */ |
1289 | ||
1290 | typedef struct value_expr_d | |
1291 | { | |
1292 | int value; | |
1293 | struct value_expr_d *next; | |
1294 | } *value_expr_p; | |
1295 | ||
1296 | ||
1297 | /* Temporary Expression Replacement (TER) table information. */ | |
1298 | ||
1299 | typedef struct temp_expr_table_d | |
1300 | { | |
1301 | var_map map; | |
1302 | void **version_info; | |
1303 | value_expr_p *partition_dep_list; | |
1304 | bitmap replaceable; | |
1305 | bool saw_replaceable; | |
1306 | int virtual_partition; | |
1307 | bitmap partition_in_use; | |
1308 | value_expr_p free_list; | |
1309 | value_expr_p pending_dependence; | |
1310 | } *temp_expr_table_p; | |
1311 | ||
61ada8ae | 1312 | /* Used to indicate a dependency on V_MAY_DEFs. */ |
6de9cd9a DN |
1313 | #define VIRTUAL_PARTITION(table) (table->virtual_partition) |
1314 | ||
1315 | static temp_expr_table_p new_temp_expr_table (var_map); | |
1316 | static tree *free_temp_expr_table (temp_expr_table_p); | |
1317 | static inline value_expr_p new_value_expr (temp_expr_table_p); | |
1318 | static inline void free_value_expr (temp_expr_table_p, value_expr_p); | |
1319 | static inline value_expr_p find_value_in_list (value_expr_p, int, | |
1320 | value_expr_p *); | |
1321 | static inline void add_value_to_list (temp_expr_table_p, value_expr_p *, int); | |
1322 | static inline void add_info_to_list (temp_expr_table_p, value_expr_p *, | |
1323 | value_expr_p); | |
1324 | static value_expr_p remove_value_from_list (value_expr_p *, int); | |
1325 | static void add_dependance (temp_expr_table_p, int, tree); | |
1326 | static bool check_replaceable (temp_expr_table_p, tree); | |
1327 | static void finish_expr (temp_expr_table_p, int, bool); | |
1328 | static void mark_replaceable (temp_expr_table_p, tree); | |
1329 | static inline void kill_expr (temp_expr_table_p, int, bool); | |
1330 | static inline void kill_virtual_exprs (temp_expr_table_p, bool); | |
1331 | static void find_replaceable_in_bb (temp_expr_table_p, basic_block); | |
1332 | static tree *find_replaceable_exprs (var_map); | |
1333 | static void dump_replaceable_exprs (FILE *, tree *); | |
1334 | ||
1335 | ||
1336 | /* Create a new TER table for MAP. */ | |
1337 | ||
1338 | static temp_expr_table_p | |
1339 | new_temp_expr_table (var_map map) | |
1340 | { | |
1341 | temp_expr_table_p t; | |
1342 | ||
1343 | t = (temp_expr_table_p) xmalloc (sizeof (struct temp_expr_table_d)); | |
1344 | t->map = map; | |
1345 | ||
95a3742c | 1346 | t->version_info = xcalloc (num_ssa_names + 1, sizeof (void *)); |
6de9cd9a DN |
1347 | t->partition_dep_list = xcalloc (num_var_partitions (map) + 1, |
1348 | sizeof (value_expr_p)); | |
1349 | ||
8bdbfff5 NS |
1350 | t->replaceable = BITMAP_ALLOC (NULL); |
1351 | t->partition_in_use = BITMAP_ALLOC (NULL); | |
6de9cd9a DN |
1352 | |
1353 | t->saw_replaceable = false; | |
1354 | t->virtual_partition = num_var_partitions (map); | |
1355 | t->free_list = NULL; | |
1356 | t->pending_dependence = NULL; | |
1357 | ||
1358 | return t; | |
1359 | } | |
1360 | ||
1361 | ||
1362 | /* Free TER table T. If there are valid replacements, return the expression | |
1363 | vector. */ | |
1364 | ||
1365 | static tree * | |
1366 | free_temp_expr_table (temp_expr_table_p t) | |
1367 | { | |
1368 | value_expr_p p; | |
1369 | tree *ret = NULL; | |
1370 | ||
1371 | #ifdef ENABLE_CHECKING | |
3cd8c58a | 1372 | unsigned x; |
6de9cd9a | 1373 | for (x = 0; x <= num_var_partitions (t->map); x++) |
e1537934 | 1374 | gcc_assert (!t->partition_dep_list[x]); |
6de9cd9a DN |
1375 | #endif |
1376 | ||
1377 | while ((p = t->free_list)) | |
1378 | { | |
1379 | t->free_list = p->next; | |
1380 | free (p); | |
1381 | } | |
1382 | ||
8bdbfff5 NS |
1383 | BITMAP_FREE (t->partition_in_use); |
1384 | BITMAP_FREE (t->replaceable); | |
6de9cd9a DN |
1385 | |
1386 | free (t->partition_dep_list); | |
1387 | if (t->saw_replaceable) | |
1388 | ret = (tree *)t->version_info; | |
1389 | else | |
1390 | free (t->version_info); | |
1391 | ||
1392 | free (t); | |
1393 | return ret; | |
1394 | } | |
1395 | ||
1396 | ||
1397 | /* Allocate a new value list node. Take it from the free list in TABLE if | |
1398 | possible. */ | |
1399 | ||
1400 | static inline value_expr_p | |
1401 | new_value_expr (temp_expr_table_p table) | |
1402 | { | |
1403 | value_expr_p p; | |
1404 | if (table->free_list) | |
1405 | { | |
1406 | p = table->free_list; | |
1407 | table->free_list = p->next; | |
1408 | } | |
1409 | else | |
1410 | p = (value_expr_p) xmalloc (sizeof (struct value_expr_d)); | |
1411 | ||
1412 | return p; | |
1413 | } | |
1414 | ||
1415 | ||
1416 | /* Add value list node P to the free list in TABLE. */ | |
1417 | ||
1418 | static inline void | |
1419 | free_value_expr (temp_expr_table_p table, value_expr_p p) | |
1420 | { | |
1421 | p->next = table->free_list; | |
1422 | table->free_list = p; | |
1423 | } | |
1424 | ||
1425 | ||
1dee9d0d | 1426 | /* Find VALUE if it's in LIST. Return a pointer to the list object if found, |
6de9cd9a DN |
1427 | else return NULL. If LAST_PTR is provided, it will point to the previous |
1428 | item upon return, or NULL if this is the first item in the list. */ | |
1429 | ||
1430 | static inline value_expr_p | |
1431 | find_value_in_list (value_expr_p list, int value, value_expr_p *last_ptr) | |
1432 | { | |
1433 | value_expr_p curr; | |
1434 | value_expr_p last = NULL; | |
1435 | ||
1436 | for (curr = list; curr; last = curr, curr = curr->next) | |
1437 | { | |
1438 | if (curr->value == value) | |
1439 | break; | |
1440 | } | |
1441 | if (last_ptr) | |
1442 | *last_ptr = last; | |
1443 | return curr; | |
1444 | } | |
1445 | ||
1446 | ||
1447 | /* Add VALUE to LIST, if it isn't already present. TAB is the expression | |
1448 | table */ | |
1449 | ||
1450 | static inline void | |
1451 | add_value_to_list (temp_expr_table_p tab, value_expr_p *list, int value) | |
1452 | { | |
1453 | value_expr_p info; | |
1454 | ||
1455 | if (!find_value_in_list (*list, value, NULL)) | |
1456 | { | |
1457 | info = new_value_expr (tab); | |
1458 | info->value = value; | |
1459 | info->next = *list; | |
1460 | *list = info; | |
1461 | } | |
1462 | } | |
1463 | ||
1464 | ||
1465 | /* Add value node INFO if it's value isn't already in LIST. Free INFO if | |
1466 | it is already in the list. TAB is the expression table. */ | |
1467 | ||
1468 | static inline void | |
1469 | add_info_to_list (temp_expr_table_p tab, value_expr_p *list, value_expr_p info) | |
1470 | { | |
1471 | if (find_value_in_list (*list, info->value, NULL)) | |
1472 | free_value_expr (tab, info); | |
1473 | else | |
1474 | { | |
1475 | info->next = *list; | |
1476 | *list = info; | |
1477 | } | |
1478 | } | |
1479 | ||
1480 | ||
1481 | /* Look for VALUE in LIST. If found, remove it from the list and return it's | |
1482 | pointer. */ | |
1483 | ||
1484 | static value_expr_p | |
1485 | remove_value_from_list (value_expr_p *list, int value) | |
1486 | { | |
1487 | value_expr_p info, last; | |
1488 | ||
1489 | info = find_value_in_list (*list, value, &last); | |
1490 | if (!info) | |
1491 | return NULL; | |
1492 | if (!last) | |
1493 | *list = info->next; | |
1494 | else | |
1495 | last->next = info->next; | |
1496 | ||
1497 | return info; | |
1498 | } | |
1499 | ||
1500 | ||
61ada8ae KH |
1501 | /* Add a dependency between the def of ssa VERSION and VAR. If VAR is |
1502 | replaceable by an expression, add a dependence each of the elements of the | |
6de9cd9a DN |
1503 | expression. These are contained in the pending list. TAB is the |
1504 | expression table. */ | |
1505 | ||
1506 | static void | |
1507 | add_dependance (temp_expr_table_p tab, int version, tree var) | |
1508 | { | |
1509 | int i, x; | |
1510 | value_expr_p info; | |
1511 | ||
1512 | i = SSA_NAME_VERSION (var); | |
1513 | if (bitmap_bit_p (tab->replaceable, i)) | |
1514 | { | |
1515 | /* This variable is being substituted, so use whatever dependences | |
1516 | were queued up when we marked this as replaceable earlier. */ | |
1517 | while ((info = tab->pending_dependence)) | |
1518 | { | |
1519 | tab->pending_dependence = info->next; | |
1520 | /* Get the partition this variable was dependent on. Reuse this | |
1521 | object to represent the current expression instead. */ | |
1522 | x = info->value; | |
1523 | info->value = version; | |
1524 | add_info_to_list (tab, &(tab->partition_dep_list[x]), info); | |
1525 | add_value_to_list (tab, | |
1526 | (value_expr_p *)&(tab->version_info[version]), x); | |
1527 | bitmap_set_bit (tab->partition_in_use, x); | |
1528 | } | |
1529 | } | |
1530 | else | |
1531 | { | |
1532 | i = var_to_partition (tab->map, var); | |
1e128c5f | 1533 | gcc_assert (i != NO_PARTITION); |
6de9cd9a DN |
1534 | add_value_to_list (tab, &(tab->partition_dep_list[i]), version); |
1535 | add_value_to_list (tab, | |
1536 | (value_expr_p *)&(tab->version_info[version]), i); | |
1537 | bitmap_set_bit (tab->partition_in_use, i); | |
1538 | } | |
1539 | } | |
1540 | ||
1541 | ||
1542 | /* Check if expression STMT is suitable for replacement in table TAB. If so, | |
1543 | create an expression entry. Return true if this stmt is replaceable. */ | |
1544 | ||
1545 | static bool | |
1546 | check_replaceable (temp_expr_table_p tab, tree stmt) | |
1547 | { | |
6de9cd9a | 1548 | tree var, def; |
f47c96aa | 1549 | int version; |
6de9cd9a | 1550 | var_map map = tab->map; |
4c124b4c | 1551 | ssa_op_iter iter; |
87637d21 | 1552 | tree call_expr; |
6de9cd9a DN |
1553 | |
1554 | if (TREE_CODE (stmt) != MODIFY_EXPR) | |
1555 | return false; | |
1556 | ||
6de9cd9a | 1557 | /* Punt if there is more than 1 def, or more than 1 use. */ |
f47c96aa AM |
1558 | def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF); |
1559 | if (!def) | |
6de9cd9a DN |
1560 | return false; |
1561 | ||
f47c96aa | 1562 | if (version_ref_count (map, def) != 1) |
a32b97a2 BB |
1563 | return false; |
1564 | ||
f47c96aa AM |
1565 | /* There must be no V_MAY_DEFS or V_MUST_DEFS. */ |
1566 | if (!(ZERO_SSA_OPERANDS (stmt, (SSA_OP_VMAYDEF | SSA_OP_VMUSTDEF)))) | |
6de9cd9a DN |
1567 | return false; |
1568 | ||
1569 | /* Float expressions must go through memory if float-store is on. */ | |
1570 | if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (stmt, 1)))) | |
1571 | return false; | |
1572 | ||
87637d21 DN |
1573 | /* Calls to functions with side-effects cannot be replaced. */ |
1574 | if ((call_expr = get_call_expr_in (stmt)) != NULL_TREE) | |
1575 | { | |
1576 | int call_flags = call_expr_flags (call_expr); | |
1577 | if (TREE_SIDE_EFFECTS (call_expr) | |
1578 | && !(call_flags & (ECF_PURE | ECF_CONST | ECF_NORETURN))) | |
1579 | return false; | |
1580 | } | |
1581 | ||
6de9cd9a DN |
1582 | version = SSA_NAME_VERSION (def); |
1583 | ||
61ada8ae | 1584 | /* Add this expression to the dependency list for each use partition. */ |
4c124b4c | 1585 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1586 | { |
6de9cd9a DN |
1587 | add_dependance (tab, version, var); |
1588 | } | |
1589 | ||
1590 | /* If there are VUSES, add a dependence on virtual defs. */ | |
f47c96aa | 1591 | if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VUSE)) |
6de9cd9a DN |
1592 | { |
1593 | add_value_to_list (tab, (value_expr_p *)&(tab->version_info[version]), | |
1594 | VIRTUAL_PARTITION (tab)); | |
1595 | add_value_to_list (tab, | |
1596 | &(tab->partition_dep_list[VIRTUAL_PARTITION (tab)]), | |
1597 | version); | |
1598 | bitmap_set_bit (tab->partition_in_use, VIRTUAL_PARTITION (tab)); | |
1599 | } | |
1600 | ||
1601 | return true; | |
1602 | } | |
1603 | ||
1604 | ||
1605 | /* This function will remove the expression for VERSION from replacement | |
1606 | consideration.n table TAB If 'replace' is true, it is marked as | |
1607 | replaceable, otherwise not. */ | |
1608 | ||
1609 | static void | |
1610 | finish_expr (temp_expr_table_p tab, int version, bool replace) | |
1611 | { | |
1612 | value_expr_p info, tmp; | |
1613 | int partition; | |
1614 | ||
61ada8ae | 1615 | /* Remove this expression from its dependent lists. The partition dependence |
6de9cd9a DN |
1616 | list is retained and transfered later to whomever uses this version. */ |
1617 | for (info = (value_expr_p) tab->version_info[version]; info; info = tmp) | |
1618 | { | |
1619 | partition = info->value; | |
1e128c5f | 1620 | gcc_assert (tab->partition_dep_list[partition]); |
6de9cd9a DN |
1621 | tmp = remove_value_from_list (&(tab->partition_dep_list[partition]), |
1622 | version); | |
1e128c5f | 1623 | gcc_assert (tmp); |
6de9cd9a | 1624 | free_value_expr (tab, tmp); |
61ada8ae | 1625 | /* Only clear the bit when the dependency list is emptied via |
6de9cd9a DN |
1626 | a replacement. Otherwise kill_expr will take care of it. */ |
1627 | if (!(tab->partition_dep_list[partition]) && replace) | |
1628 | bitmap_clear_bit (tab->partition_in_use, partition); | |
1629 | tmp = info->next; | |
1630 | if (!replace) | |
1631 | free_value_expr (tab, info); | |
1632 | } | |
1633 | ||
1634 | if (replace) | |
1635 | { | |
1636 | tab->saw_replaceable = true; | |
1637 | bitmap_set_bit (tab->replaceable, version); | |
1638 | } | |
1639 | else | |
1640 | { | |
1e128c5f | 1641 | gcc_assert (!bitmap_bit_p (tab->replaceable, version)); |
6de9cd9a DN |
1642 | tab->version_info[version] = NULL; |
1643 | } | |
1644 | } | |
1645 | ||
1646 | ||
1647 | /* Mark the expression associated with VAR as replaceable, and enter | |
1648 | the defining stmt into the version_info table TAB. */ | |
1649 | ||
1650 | static void | |
1651 | mark_replaceable (temp_expr_table_p tab, tree var) | |
1652 | { | |
1653 | value_expr_p info; | |
1654 | int version = SSA_NAME_VERSION (var); | |
1655 | finish_expr (tab, version, true); | |
1656 | ||
1657 | /* Move the dependence list to the pending list. */ | |
1658 | if (tab->version_info[version]) | |
1659 | { | |
1660 | info = (value_expr_p) tab->version_info[version]; | |
1661 | for ( ; info->next; info = info->next) | |
1662 | continue; | |
1663 | info->next = tab->pending_dependence; | |
1664 | tab->pending_dependence = (value_expr_p)tab->version_info[version]; | |
1665 | } | |
1666 | ||
1667 | tab->version_info[version] = SSA_NAME_DEF_STMT (var); | |
1668 | } | |
1669 | ||
1670 | ||
1671 | /* This function marks any expression in TAB which is dependent on PARTITION | |
1672 | as NOT replaceable. CLEAR_BIT is used to determine whether partition_in_use | |
1673 | should have its bit cleared. Since this routine can be called within an | |
1674 | EXECUTE_IF_SET_IN_BITMAP, the bit can't always be cleared. */ | |
1675 | ||
1676 | static inline void | |
1677 | kill_expr (temp_expr_table_p tab, int partition, bool clear_bit) | |
1678 | { | |
1679 | value_expr_p ptr; | |
1680 | ||
61ada8ae | 1681 | /* Mark every active expr dependent on this var as not replaceable. */ |
6de9cd9a DN |
1682 | while ((ptr = tab->partition_dep_list[partition]) != NULL) |
1683 | finish_expr (tab, ptr->value, false); | |
1684 | ||
1685 | if (clear_bit) | |
1686 | bitmap_clear_bit (tab->partition_in_use, partition); | |
1687 | } | |
1688 | ||
1689 | ||
61ada8ae | 1690 | /* This function kills all expressions in TAB which are dependent on virtual |
6de9cd9a DN |
1691 | DEFs. CLEAR_BIT determines whether partition_in_use gets cleared. */ |
1692 | ||
1693 | static inline void | |
1694 | kill_virtual_exprs (temp_expr_table_p tab, bool clear_bit) | |
1695 | { | |
1696 | kill_expr (tab, VIRTUAL_PARTITION (tab), clear_bit); | |
1697 | } | |
1698 | ||
1699 | ||
1700 | /* This function processes basic block BB, and looks for variables which can | |
1701 | be replaced by their expressions. Results are stored in TAB. */ | |
1702 | ||
1703 | static void | |
1704 | find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb) | |
1705 | { | |
1706 | block_stmt_iterator bsi; | |
1707 | tree stmt, def; | |
1708 | stmt_ann_t ann; | |
4c124b4c | 1709 | int partition; |
6de9cd9a DN |
1710 | var_map map = tab->map; |
1711 | value_expr_p p; | |
4c124b4c | 1712 | ssa_op_iter iter; |
6de9cd9a DN |
1713 | |
1714 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1715 | { | |
1716 | stmt = bsi_stmt (bsi); | |
1717 | ann = stmt_ann (stmt); | |
1718 | ||
1719 | /* Determine if this stmt finishes an existing expression. */ | |
4c124b4c | 1720 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1721 | { |
6de9cd9a DN |
1722 | if (tab->version_info[SSA_NAME_VERSION (def)]) |
1723 | { | |
3b6616dd SB |
1724 | bool same_root_var = false; |
1725 | tree def2; | |
1726 | ssa_op_iter iter2; | |
1727 | ||
1728 | /* See if the root variables are the same. If they are, we | |
1729 | do not want to do the replacement to avoid problems with | |
1730 | code size, see PR tree-optimization/17549. */ | |
1731 | FOR_EACH_SSA_TREE_OPERAND (def2, stmt, iter2, SSA_OP_DEF) | |
1732 | if (SSA_NAME_VAR (def) == SSA_NAME_VAR (def2)) | |
1733 | { | |
1734 | same_root_var = true; | |
1735 | break; | |
1736 | } | |
1737 | ||
1738 | /* Mark expression as replaceable unless stmt is volatile | |
1739 | or DEF sets the same root variable as STMT. */ | |
1740 | if (!ann->has_volatile_ops && !same_root_var) | |
6de9cd9a DN |
1741 | mark_replaceable (tab, def); |
1742 | else | |
1743 | finish_expr (tab, SSA_NAME_VERSION (def), false); | |
1744 | } | |
1745 | } | |
1746 | ||
1747 | /* Next, see if this stmt kills off an active expression. */ | |
4c124b4c | 1748 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF) |
6de9cd9a | 1749 | { |
6de9cd9a DN |
1750 | partition = var_to_partition (map, def); |
1751 | if (partition != NO_PARTITION && tab->partition_dep_list[partition]) | |
1752 | kill_expr (tab, partition, true); | |
1753 | } | |
1754 | ||
1755 | /* Now see if we are creating a new expression or not. */ | |
1756 | if (!ann->has_volatile_ops) | |
1757 | check_replaceable (tab, stmt); | |
1758 | ||
61ada8ae | 1759 | /* Free any unused dependency lists. */ |
6de9cd9a DN |
1760 | while ((p = tab->pending_dependence)) |
1761 | { | |
1762 | tab->pending_dependence = p->next; | |
1763 | free_value_expr (tab, p); | |
1764 | } | |
1765 | ||
f47c96aa AM |
1766 | /* A V_{MAY,MUST}_DEF kills any expression using a virtual operand. */ |
1767 | if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS)) | |
6de9cd9a DN |
1768 | kill_virtual_exprs (tab, true); |
1769 | } | |
1770 | } | |
1771 | ||
1772 | ||
1773 | /* This function is the driver routine for replacement of temporary expressions | |
1774 | in the SSA->normal phase, operating on MAP. If there are replaceable | |
1775 | expressions, a table is returned which maps SSA versions to the | |
1776 | expressions they should be replaced with. A NULL_TREE indicates no | |
1777 | replacement should take place. If there are no replacements at all, | |
1778 | NULL is returned by the function, otherwise an expression vector indexed | |
1779 | by SSA_NAME version numbers. */ | |
1780 | ||
1781 | static tree * | |
1782 | find_replaceable_exprs (var_map map) | |
1783 | { | |
1784 | basic_block bb; | |
3cd8c58a | 1785 | unsigned i; |
6de9cd9a DN |
1786 | temp_expr_table_p table; |
1787 | tree *ret; | |
1788 | ||
1789 | table = new_temp_expr_table (map); | |
1790 | FOR_EACH_BB (bb) | |
1791 | { | |
87c476a2 ZD |
1792 | bitmap_iterator bi; |
1793 | ||
6de9cd9a | 1794 | find_replaceable_in_bb (table, bb); |
87c476a2 | 1795 | EXECUTE_IF_SET_IN_BITMAP ((table->partition_in_use), 0, i, bi) |
6de9cd9a DN |
1796 | { |
1797 | kill_expr (table, i, false); | |
87c476a2 | 1798 | } |
6de9cd9a DN |
1799 | } |
1800 | ||
1801 | ret = free_temp_expr_table (table); | |
1802 | return ret; | |
1803 | } | |
1804 | ||
1805 | ||
1806 | /* Dump TER expression table EXPR to file F. */ | |
1807 | ||
1808 | static void | |
1809 | dump_replaceable_exprs (FILE *f, tree *expr) | |
1810 | { | |
1811 | tree stmt, var; | |
1812 | int x; | |
1813 | fprintf (f, "\nReplacing Expressions\n"); | |
95a3742c | 1814 | for (x = 0; x < (int)num_ssa_names + 1; x++) |
6de9cd9a DN |
1815 | if (expr[x]) |
1816 | { | |
1817 | stmt = expr[x]; | |
f47c96aa AM |
1818 | var = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF); |
1819 | gcc_assert (var != NULL_TREE); | |
6de9cd9a DN |
1820 | print_generic_expr (f, var, TDF_SLIM); |
1821 | fprintf (f, " replace with --> "); | |
1822 | print_generic_expr (f, TREE_OPERAND (stmt, 1), TDF_SLIM); | |
1823 | fprintf (f, "\n"); | |
1824 | } | |
1825 | fprintf (f, "\n"); | |
1826 | } | |
1827 | ||
1828 | ||
6de9cd9a DN |
1829 | /* This function will rewrite the current program using the variable mapping |
1830 | found in MAP. If the replacement vector VALUES is provided, any | |
1831 | occurrences of partitions with non-null entries in the vector will be | |
1832 | replaced with the expression in the vector instead of its mapped | |
1833 | variable. */ | |
1834 | ||
1835 | static void | |
1836 | rewrite_trees (var_map map, tree *values) | |
1837 | { | |
1838 | elim_graph g; | |
1839 | basic_block bb; | |
1840 | block_stmt_iterator si; | |
1841 | edge e; | |
1842 | tree phi; | |
1843 | bool changed; | |
1844 | ||
1845 | #ifdef ENABLE_CHECKING | |
1846 | /* Search for PHIs where the destination has no partition, but one | |
1847 | or more arguments has a partition. This should not happen and can | |
1848 | create incorrect code. */ | |
1849 | FOR_EACH_BB (bb) | |
1850 | { | |
1851 | tree phi; | |
1852 | ||
17192884 | 1853 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
1854 | { |
1855 | tree T0 = var_to_partition_to_var (map, PHI_RESULT (phi)); | |
1856 | ||
1857 | if (T0 == NULL_TREE) | |
1858 | { | |
1859 | int i; | |
1860 | ||
1861 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
1862 | { | |
1863 | tree arg = PHI_ARG_DEF (phi, i); | |
1864 | ||
1865 | if (TREE_CODE (arg) == SSA_NAME | |
1866 | && var_to_partition (map, arg) != NO_PARTITION) | |
1867 | { | |
1868 | fprintf (stderr, "Argument of PHI is in a partition :("); | |
1869 | print_generic_expr (stderr, arg, TDF_SLIM); | |
1870 | fprintf (stderr, "), but the result is not :"); | |
1871 | print_generic_stmt (stderr, phi, TDF_SLIM); | |
1e128c5f | 1872 | internal_error ("SSA corruption"); |
6de9cd9a DN |
1873 | } |
1874 | } | |
1875 | } | |
1876 | } | |
1877 | } | |
1878 | #endif | |
1879 | ||
1880 | /* Replace PHI nodes with any required copies. */ | |
1881 | g = new_elim_graph (map->num_partitions); | |
1882 | g->map = map; | |
1883 | FOR_EACH_BB (bb) | |
1884 | { | |
1885 | for (si = bsi_start (bb); !bsi_end_p (si); ) | |
1886 | { | |
6de9cd9a | 1887 | tree stmt = bsi_stmt (si); |
f47c96aa | 1888 | use_operand_p use_p, copy_use_p; |
4c124b4c | 1889 | def_operand_p def_p; |
f47c96aa AM |
1890 | bool remove = false, is_copy = false; |
1891 | int num_uses = 0; | |
6de9cd9a | 1892 | stmt_ann_t ann; |
4c124b4c | 1893 | ssa_op_iter iter; |
6de9cd9a | 1894 | |
6de9cd9a DN |
1895 | ann = stmt_ann (stmt); |
1896 | changed = false; | |
1897 | ||
1898 | if (TREE_CODE (stmt) == MODIFY_EXPR | |
1899 | && (TREE_CODE (TREE_OPERAND (stmt, 1)) == SSA_NAME)) | |
f47c96aa | 1900 | is_copy = true; |
6de9cd9a | 1901 | |
f47c96aa | 1902 | copy_use_p = NULL_USE_OPERAND_P; |
4c124b4c | 1903 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) |
6de9cd9a | 1904 | { |
d00ad49b | 1905 | if (replace_use_variable (map, use_p, values)) |
f47c96aa AM |
1906 | changed = true; |
1907 | copy_use_p = use_p; | |
1908 | num_uses++; | |
6de9cd9a DN |
1909 | } |
1910 | ||
f47c96aa AM |
1911 | if (num_uses != 1) |
1912 | is_copy = false; | |
6de9cd9a | 1913 | |
f47c96aa AM |
1914 | def_p = SINGLE_SSA_DEF_OPERAND (stmt, SSA_OP_DEF); |
1915 | ||
1916 | if (def_p != NULL) | |
6de9cd9a | 1917 | { |
f47c96aa AM |
1918 | /* Mark this stmt for removal if it is the list of replaceable |
1919 | expressions. */ | |
1920 | if (values && values[SSA_NAME_VERSION (DEF_FROM_PTR (def_p))]) | |
1921 | remove = true; | |
1922 | else | |
6de9cd9a | 1923 | { |
d00ad49b | 1924 | if (replace_def_variable (map, def_p, NULL)) |
6de9cd9a | 1925 | changed = true; |
6de9cd9a DN |
1926 | /* If both SSA_NAMEs coalesce to the same variable, |
1927 | mark the now redundant copy for removal. */ | |
f47c96aa AM |
1928 | if (is_copy) |
1929 | { | |
1930 | gcc_assert (copy_use_p != NULL_USE_OPERAND_P); | |
1931 | if (DEF_FROM_PTR (def_p) == USE_FROM_PTR (copy_use_p)) | |
1932 | remove = true; | |
1933 | } | |
6de9cd9a | 1934 | } |
6de9cd9a | 1935 | } |
f47c96aa AM |
1936 | else |
1937 | FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_DEF) | |
1938 | if (replace_def_variable (map, def_p, NULL)) | |
1939 | changed = true; | |
6de9cd9a DN |
1940 | |
1941 | /* Remove any stmts marked for removal. */ | |
1942 | if (remove) | |
1943 | bsi_remove (&si); | |
1944 | else | |
1945 | bsi_next (&si); | |
1946 | } | |
1947 | ||
1948 | phi = phi_nodes (bb); | |
1949 | if (phi) | |
1950 | { | |
628f6a4e BE |
1951 | edge_iterator ei; |
1952 | FOR_EACH_EDGE (e, ei, bb->preds) | |
41f683ef | 1953 | eliminate_phi (e, g); |
6de9cd9a DN |
1954 | } |
1955 | } | |
1956 | ||
1957 | delete_elim_graph (g); | |
edfaf675 AM |
1958 | } |
1959 | ||
1960 | ||
5ea30da0 KH |
1961 | DEF_VEC_ALLOC_P(edge,heap); |
1962 | ||
edfaf675 AM |
1963 | /* These are the local work structures used to determine the best place to |
1964 | insert the copies that were placed on edges by the SSA->normal pass.. */ | |
5ea30da0 KH |
1965 | static VEC(edge,heap) *edge_leader; |
1966 | static VEC(tree,heap) *stmt_list; | |
edfaf675 AM |
1967 | static bitmap leader_has_match = NULL; |
1968 | static edge leader_match = NULL; | |
1969 | ||
1970 | ||
1971 | /* Pass this function to make_forwarder_block so that all the edges with | |
1972 | matching PENDING_STMT lists to 'curr_stmt_list' get redirected. */ | |
1973 | static bool | |
1974 | same_stmt_list_p (edge e) | |
1975 | { | |
1976 | return (e->aux == (PTR) leader_match) ? true : false; | |
1977 | } | |
1978 | ||
1979 | ||
1980 | /* Return TRUE if S1 and S2 are equivalent copies. */ | |
1981 | static inline bool | |
1982 | identical_copies_p (tree s1, tree s2) | |
1983 | { | |
1984 | #ifdef ENABLE_CHECKING | |
1985 | gcc_assert (TREE_CODE (s1) == MODIFY_EXPR); | |
1986 | gcc_assert (TREE_CODE (s2) == MODIFY_EXPR); | |
1987 | gcc_assert (DECL_P (TREE_OPERAND (s1, 0))); | |
1988 | gcc_assert (DECL_P (TREE_OPERAND (s2, 0))); | |
1989 | #endif | |
1990 | ||
1991 | if (TREE_OPERAND (s1, 0) != TREE_OPERAND (s2, 0)) | |
1992 | return false; | |
1993 | ||
1994 | s1 = TREE_OPERAND (s1, 1); | |
1995 | s2 = TREE_OPERAND (s2, 1); | |
1996 | ||
1997 | if (s1 != s2) | |
1998 | return false; | |
1999 | ||
2000 | return true; | |
2001 | } | |
2002 | ||
2003 | ||
2004 | /* Compare the PENDING_STMT list for two edges, and return true if the lists | |
2005 | contain the same sequence of copies. */ | |
2006 | ||
2007 | static inline bool | |
2008 | identical_stmt_lists_p (edge e1, edge e2) | |
2009 | { | |
2010 | tree t1 = PENDING_STMT (e1); | |
2011 | tree t2 = PENDING_STMT (e2); | |
2012 | tree_stmt_iterator tsi1, tsi2; | |
2013 | ||
2014 | gcc_assert (TREE_CODE (t1) == STATEMENT_LIST); | |
2015 | gcc_assert (TREE_CODE (t2) == STATEMENT_LIST); | |
2016 | ||
2017 | for (tsi1 = tsi_start (t1), tsi2 = tsi_start (t2); | |
2018 | !tsi_end_p (tsi1) && !tsi_end_p (tsi2); | |
2019 | tsi_next (&tsi1), tsi_next (&tsi2)) | |
2020 | { | |
2021 | if (!identical_copies_p (tsi_stmt (tsi1), tsi_stmt (tsi2))) | |
2022 | break; | |
2023 | } | |
2024 | ||
2025 | if (!tsi_end_p (tsi1) || ! tsi_end_p (tsi2)) | |
2026 | return false; | |
2027 | ||
2028 | return true; | |
2029 | } | |
2030 | ||
2031 | ||
5ea30da0 KH |
2032 | /* Allocate data structures used in analyze_edges_for_bb. */ |
2033 | ||
2034 | static void | |
2035 | init_analyze_edges_for_bb (void) | |
2036 | { | |
2037 | edge_leader = VEC_alloc (edge, heap, 25); | |
2038 | stmt_list = VEC_alloc (tree, heap, 25); | |
2039 | leader_has_match = BITMAP_ALLOC (NULL); | |
2040 | } | |
2041 | ||
2042 | ||
2043 | /* Free data structures used in analyze_edges_for_bb. */ | |
2044 | ||
2045 | static void | |
2046 | fini_analyze_edges_for_bb (void) | |
2047 | { | |
2048 | VEC_free (edge, heap, edge_leader); | |
2049 | VEC_free (tree, heap, stmt_list); | |
2050 | BITMAP_FREE (leader_has_match); | |
2051 | } | |
2052 | ||
2053 | ||
edfaf675 AM |
2054 | /* Look at all the incoming edges to block BB, and decide where the best place |
2055 | to insert the stmts on each edge are, and perform those insertions. Output | |
17008288 | 2056 | any debug information to DEBUG_FILE. */ |
edfaf675 | 2057 | |
b25a2407 | 2058 | static void |
edfaf675 AM |
2059 | analyze_edges_for_bb (basic_block bb, FILE *debug_file) |
2060 | { | |
2061 | edge e; | |
2062 | edge_iterator ei; | |
2063 | int count; | |
2064 | unsigned int x; | |
2065 | bool have_opportunity; | |
2066 | block_stmt_iterator bsi; | |
2067 | tree stmt; | |
2068 | edge single_edge = NULL; | |
2069 | bool is_label; | |
5ea30da0 | 2070 | edge leader; |
edfaf675 AM |
2071 | |
2072 | count = 0; | |
b00e4c23 AM |
2073 | |
2074 | /* Blocks which contain at least one abnormal edge cannot use | |
2075 | make_forwarder_block. Look for these blocks, and commit any PENDING_STMTs | |
2076 | found on edges in these block. */ | |
2077 | have_opportunity = true; | |
2078 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2079 | if (e->flags & EDGE_ABNORMAL) | |
2080 | { | |
2081 | have_opportunity = false; | |
2082 | break; | |
2083 | } | |
2084 | ||
2085 | if (!have_opportunity) | |
2086 | { | |
2087 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2088 | if (PENDING_STMT (e)) | |
2089 | bsi_commit_one_edge_insert (e, NULL); | |
b25a2407 | 2090 | return; |
b00e4c23 | 2091 | } |
edfaf675 AM |
2092 | /* Find out how many edges there are with interesting pending stmts on them. |
2093 | Commit the stmts on edges we are not interested in. */ | |
2094 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2095 | { | |
2096 | if (PENDING_STMT (e)) | |
2097 | { | |
2098 | gcc_assert (!(e->flags & EDGE_ABNORMAL)); | |
2099 | if (e->flags & EDGE_FALLTHRU) | |
2100 | { | |
2101 | bsi = bsi_start (e->src); | |
2102 | if (!bsi_end_p (bsi)) | |
2103 | { | |
2104 | stmt = bsi_stmt (bsi); | |
2105 | bsi_next (&bsi); | |
2106 | gcc_assert (stmt != NULL_TREE); | |
2107 | is_label = (TREE_CODE (stmt) == LABEL_EXPR); | |
2108 | /* Punt if it has non-label stmts, or isn't local. */ | |
2109 | if (!is_label || DECL_NONLOCAL (TREE_OPERAND (stmt, 0)) | |
2110 | || !bsi_end_p (bsi)) | |
2111 | { | |
2112 | bsi_commit_one_edge_insert (e, NULL); | |
2113 | continue; | |
2114 | } | |
2115 | } | |
2116 | } | |
2117 | single_edge = e; | |
2118 | count++; | |
2119 | } | |
2120 | } | |
2121 | ||
2122 | /* If there aren't at least 2 edges, no sharing will happen. */ | |
2123 | if (count < 2) | |
2124 | { | |
2125 | if (single_edge) | |
2126 | bsi_commit_one_edge_insert (single_edge, NULL); | |
b25a2407 | 2127 | return; |
edfaf675 AM |
2128 | } |
2129 | ||
2130 | /* Ensure that we have empty worklists. */ | |
edfaf675 | 2131 | #ifdef ENABLE_CHECKING |
5ea30da0 KH |
2132 | gcc_assert (VEC_length (edge, edge_leader) == 0); |
2133 | gcc_assert (VEC_length (tree, stmt_list) == 0); | |
2134 | gcc_assert (bitmap_empty_p (leader_has_match)); | |
edfaf675 | 2135 | #endif |
edfaf675 AM |
2136 | |
2137 | /* Find the "leader" block for each set of unique stmt lists. Preference is | |
2138 | given to FALLTHRU blocks since they would need a GOTO to arrive at another | |
2139 | block. The leader edge destination is the block which all the other edges | |
2140 | with the same stmt list will be redirected to. */ | |
2141 | have_opportunity = false; | |
2142 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2143 | { | |
2144 | if (PENDING_STMT (e)) | |
2145 | { | |
2146 | bool found = false; | |
2147 | ||
2148 | /* Look for the same stmt list in edge leaders list. */ | |
5ea30da0 | 2149 | for (x = 0; VEC_iterate (edge, edge_leader, x, leader); x++) |
edfaf675 | 2150 | { |
edfaf675 AM |
2151 | if (identical_stmt_lists_p (leader, e)) |
2152 | { | |
2153 | /* Give this edge the same stmt list pointer. */ | |
2154 | PENDING_STMT (e) = NULL; | |
2155 | e->aux = leader; | |
2156 | bitmap_set_bit (leader_has_match, x); | |
2157 | have_opportunity = found = true; | |
2158 | break; | |
2159 | } | |
2160 | } | |
2161 | ||
2162 | /* If no similar stmt list, add this edge to the leader list. */ | |
2163 | if (!found) | |
2164 | { | |
5ea30da0 KH |
2165 | VEC_safe_push (edge, heap, edge_leader, e); |
2166 | VEC_safe_push (tree, heap, stmt_list, PENDING_STMT (e)); | |
edfaf675 AM |
2167 | } |
2168 | } | |
2169 | } | |
2170 | ||
2171 | /* If there are no similar lists, just issue the stmts. */ | |
2172 | if (!have_opportunity) | |
2173 | { | |
5ea30da0 KH |
2174 | for (x = 0; VEC_iterate (edge, edge_leader, x, leader); x++) |
2175 | bsi_commit_one_edge_insert (leader, NULL); | |
2176 | VEC_truncate (edge, edge_leader, 0); | |
2177 | VEC_truncate (tree, stmt_list, 0); | |
edfaf675 | 2178 | bitmap_clear (leader_has_match); |
b25a2407 | 2179 | return; |
edfaf675 AM |
2180 | } |
2181 | ||
2182 | ||
2183 | if (debug_file) | |
2184 | fprintf (debug_file, "\nOpportunities in BB %d for stmt/block reduction:\n", | |
2185 | bb->index); | |
2186 | ||
2187 | ||
2188 | /* For each common list, create a forwarding block and issue the stmt's | |
2189 | in that block. */ | |
5ea30da0 | 2190 | for (x = 0; VEC_iterate (edge, edge_leader, x, leader); x++) |
edfaf675 AM |
2191 | if (bitmap_bit_p (leader_has_match, x)) |
2192 | { | |
5ea30da0 | 2193 | edge new_edge; |
edfaf675 AM |
2194 | block_stmt_iterator bsi; |
2195 | tree curr_stmt_list; | |
2196 | ||
5ea30da0 | 2197 | leader_match = leader; |
edfaf675 AM |
2198 | |
2199 | /* The tree_* cfg manipulation routines use the PENDING_EDGE field | |
2200 | for various PHI manipulations, so it gets cleared whhen calls are | |
2201 | made to make_forwarder_block(). So make sure the edge is clear, | |
2202 | and use the saved stmt list. */ | |
5ea30da0 KH |
2203 | PENDING_STMT (leader) = NULL; |
2204 | leader->aux = leader; | |
2205 | curr_stmt_list = VEC_index (tree, stmt_list, x); | |
edfaf675 | 2206 | |
5ea30da0 | 2207 | new_edge = make_forwarder_block (leader->dest, same_stmt_list_p, |
edfaf675 AM |
2208 | NULL); |
2209 | bb = new_edge->dest; | |
2210 | if (debug_file) | |
2211 | { | |
2212 | fprintf (debug_file, "Splitting BB %d for Common stmt list. ", | |
5ea30da0 | 2213 | leader->dest->index); |
edfaf675 AM |
2214 | fprintf (debug_file, "Original block is now BB%d.\n", bb->index); |
2215 | print_generic_stmt (debug_file, curr_stmt_list, TDF_VOPS); | |
2216 | } | |
2217 | ||
2218 | FOR_EACH_EDGE (e, ei, new_edge->src->preds) | |
2219 | { | |
2220 | e->aux = NULL; | |
2221 | if (debug_file) | |
2222 | fprintf (debug_file, " Edge (%d->%d) lands here.\n", | |
2223 | e->src->index, e->dest->index); | |
2224 | } | |
2225 | ||
5ea30da0 | 2226 | bsi = bsi_last (leader->dest); |
edfaf675 AM |
2227 | bsi_insert_after (&bsi, curr_stmt_list, BSI_NEW_STMT); |
2228 | ||
2229 | leader_match = NULL; | |
2230 | /* We should never get a new block now. */ | |
2231 | } | |
2232 | else | |
2233 | { | |
5ea30da0 KH |
2234 | PENDING_STMT (leader) = VEC_index (tree, stmt_list, x); |
2235 | bsi_commit_one_edge_insert (leader, NULL); | |
edfaf675 AM |
2236 | } |
2237 | ||
2238 | ||
2239 | /* Clear the working data structures. */ | |
5ea30da0 KH |
2240 | VEC_truncate (edge, edge_leader, 0); |
2241 | VEC_truncate (tree, stmt_list, 0); | |
edfaf675 | 2242 | bitmap_clear (leader_has_match); |
edfaf675 AM |
2243 | } |
2244 | ||
2245 | ||
2246 | /* This function will analyze the insertions which were performed on edges, | |
2247 | and decide whether they should be left on that edge, or whether it is more | |
2248 | efficient to emit some subset of them in a single block. All stmts are | |
2249 | inserted somewhere, and if non-NULL, debug information is printed via | |
2250 | DUMP_FILE. */ | |
2251 | ||
2252 | static void | |
2253 | perform_edge_inserts (FILE *dump_file) | |
2254 | { | |
2255 | basic_block bb; | |
edfaf675 AM |
2256 | |
2257 | if (dump_file) | |
2258 | fprintf(dump_file, "Analyzing Edge Insertions.\n"); | |
2259 | ||
b25a2407 KH |
2260 | /* analyze_edges_for_bb calls make_forwarder_block, which tries to |
2261 | incrementally update the dominator information. Since we don't | |
2262 | need dominator information after this pass, go ahead and free the | |
2263 | dominator information. */ | |
2264 | free_dominance_info (CDI_DOMINATORS); | |
2265 | free_dominance_info (CDI_POST_DOMINATORS); | |
2266 | ||
5ea30da0 KH |
2267 | /* Allocate data structures used in analyze_edges_for_bb. */ |
2268 | init_analyze_edges_for_bb (); | |
2269 | ||
edfaf675 | 2270 | FOR_EACH_BB (bb) |
b25a2407 | 2271 | analyze_edges_for_bb (bb, dump_file); |
edfaf675 | 2272 | |
b25a2407 | 2273 | analyze_edges_for_bb (EXIT_BLOCK_PTR, dump_file); |
edfaf675 | 2274 | |
5ea30da0 KH |
2275 | /* Free data structures used in analyze_edges_for_bb. */ |
2276 | fini_analyze_edges_for_bb (); | |
6de9cd9a | 2277 | |
edfaf675 AM |
2278 | #ifdef ENABLE_CHECKING |
2279 | { | |
2280 | edge_iterator ei; | |
2281 | edge e; | |
2282 | FOR_EACH_BB (bb) | |
2283 | { | |
2284 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2285 | { | |
2286 | if (PENDING_STMT (e)) | |
2287 | error (" Pending stmts not issued on PRED edge (%d, %d)\n", | |
2288 | e->src->index, e->dest->index); | |
2289 | } | |
2290 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2291 | { | |
2292 | if (PENDING_STMT (e)) | |
2293 | error (" Pending stmts not issued on SUCC edge (%d, %d)\n", | |
2294 | e->src->index, e->dest->index); | |
2295 | } | |
2296 | } | |
2297 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) | |
2298 | { | |
2299 | if (PENDING_STMT (e)) | |
2300 | error (" Pending stmts not issued on ENTRY edge (%d, %d)\n", | |
2301 | e->src->index, e->dest->index); | |
2302 | } | |
2303 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) | |
2304 | { | |
2305 | if (PENDING_STMT (e)) | |
2306 | error (" Pending stmts not issued on EXIT edge (%d, %d)\n", | |
2307 | e->src->index, e->dest->index); | |
2308 | } | |
2309 | } | |
2310 | #endif | |
6de9cd9a DN |
2311 | } |
2312 | ||
2313 | ||
2314 | /* Remove the variables specified in MAP from SSA form. Any debug information | |
2315 | is sent to DUMP. FLAGS indicate what options should be used. */ | |
2316 | ||
56b043c8 | 2317 | static void |
6de9cd9a DN |
2318 | remove_ssa_form (FILE *dump, var_map map, int flags) |
2319 | { | |
2320 | tree_live_info_p liveinfo; | |
2321 | basic_block bb; | |
2322 | tree phi, next; | |
2323 | FILE *save; | |
2324 | tree *values = NULL; | |
2325 | ||
2326 | save = dump_file; | |
2327 | dump_file = dump; | |
2328 | ||
2329 | /* If we are not combining temps, don't calculate live ranges for variables | |
2330 | with only one SSA version. */ | |
2331 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
2332 | compact_var_map (map, VARMAP_NO_SINGLE_DEFS); | |
2333 | else | |
2334 | compact_var_map (map, VARMAP_NORMAL); | |
2335 | ||
2336 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2337 | dump_var_map (dump_file, map); | |
2338 | ||
2339 | liveinfo = coalesce_ssa_name (map, flags); | |
2340 | ||
2341 | /* Make sure even single occurrence variables are in the list now. */ | |
2342 | if ((flags & SSANORM_COMBINE_TEMPS) == 0) | |
2343 | compact_var_map (map, VARMAP_NORMAL); | |
2344 | ||
2345 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2346 | { | |
2347 | fprintf (dump_file, "After Coalescing:\n"); | |
2348 | dump_var_map (dump_file, map); | |
2349 | } | |
2350 | ||
2351 | if (flags & SSANORM_PERFORM_TER) | |
2352 | { | |
2353 | values = find_replaceable_exprs (map); | |
2354 | if (values && dump_file && (dump_flags & TDF_DETAILS)) | |
2355 | dump_replaceable_exprs (dump_file, values); | |
2356 | } | |
2357 | ||
2358 | /* Assign real variables to the partitions now. */ | |
2359 | assign_vars (map); | |
2360 | ||
2361 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2362 | { | |
2363 | fprintf (dump_file, "After Root variable replacement:\n"); | |
2364 | dump_var_map (dump_file, map); | |
2365 | } | |
2366 | ||
2367 | if ((flags & SSANORM_COMBINE_TEMPS) && liveinfo) | |
2368 | { | |
2369 | coalesce_vars (map, liveinfo); | |
2370 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2371 | { | |
2372 | fprintf (dump_file, "After variable memory coalescing:\n"); | |
2373 | dump_var_map (dump_file, map); | |
2374 | } | |
2375 | } | |
2376 | ||
2377 | if (liveinfo) | |
2378 | delete_tree_live_info (liveinfo); | |
2379 | ||
2380 | rewrite_trees (map, values); | |
2381 | ||
2382 | if (values) | |
2383 | free (values); | |
2384 | ||
2385 | /* Remove phi nodes which have been translated back to real variables. */ | |
2386 | FOR_EACH_BB (bb) | |
2387 | { | |
2388 | for (phi = phi_nodes (bb); phi; phi = next) | |
2389 | { | |
17192884 | 2390 | next = PHI_CHAIN (phi); |
d19e3ef6 | 2391 | remove_phi_node (phi, NULL_TREE); |
6de9cd9a DN |
2392 | } |
2393 | } | |
2394 | ||
f430bae8 AM |
2395 | /* we no longer maintain the SSA operand cache at this point. */ |
2396 | fini_ssa_operands (); | |
2397 | ||
edfaf675 AM |
2398 | /* If any copies were inserted on edges, analyze and insert them now. */ |
2399 | perform_edge_inserts (dump_file); | |
2400 | ||
6de9cd9a DN |
2401 | dump_file = save; |
2402 | } | |
2403 | ||
06170e1d JL |
2404 | /* Search every PHI node for arguments associated with backedges which |
2405 | we can trivially determine will need a copy (the argument is either | |
2406 | not an SSA_NAME or the argument has a different underlying variable | |
2407 | than the PHI result). | |
2408 | ||
2409 | Insert a copy from the PHI argument to a new destination at the | |
2410 | end of the block with the backedge to the top of the loop. Update | |
2411 | the PHI argument to reference this new destination. */ | |
2412 | ||
2413 | static void | |
2414 | insert_backedge_copies (void) | |
2415 | { | |
2416 | basic_block bb; | |
2417 | ||
2418 | FOR_EACH_BB (bb) | |
2419 | { | |
2420 | tree phi; | |
2421 | ||
2422 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) | |
2423 | { | |
2424 | tree result = PHI_RESULT (phi); | |
2425 | tree result_var; | |
2426 | int i; | |
2427 | ||
2428 | if (!is_gimple_reg (result)) | |
2429 | continue; | |
2430 | ||
2431 | result_var = SSA_NAME_VAR (result); | |
2432 | for (i = 0; i < PHI_NUM_ARGS (phi); i++) | |
2433 | { | |
2434 | tree arg = PHI_ARG_DEF (phi, i); | |
2435 | edge e = PHI_ARG_EDGE (phi, i); | |
2436 | ||
2437 | /* If the argument is not an SSA_NAME, then we will | |
2438 | need a constant initialization. If the argument is | |
2439 | an SSA_NAME with a different underlying variable and | |
2440 | we are not combining temporaries, then we will | |
2441 | need a copy statement. */ | |
2442 | if ((e->flags & EDGE_DFS_BACK) | |
2443 | && (TREE_CODE (arg) != SSA_NAME | |
2444 | || (!flag_tree_combine_temps | |
2445 | && SSA_NAME_VAR (arg) != result_var))) | |
2446 | { | |
2447 | tree stmt, name, last = NULL; | |
2448 | block_stmt_iterator bsi; | |
2449 | ||
2450 | bsi = bsi_last (PHI_ARG_EDGE (phi, i)->src); | |
2451 | if (!bsi_end_p (bsi)) | |
2452 | last = bsi_stmt (bsi); | |
2453 | ||
2454 | /* In theory the only way we ought to get back to the | |
2455 | start of a loop should be with a COND_EXPR or GOTO_EXPR. | |
2456 | However, better safe than sorry. | |
2457 | ||
35fd3193 | 2458 | If the block ends with a control statement or |
06170e1d JL |
2459 | something that might throw, then we have to |
2460 | insert this assignment before the last | |
2461 | statement. Else insert it after the last statement. */ | |
2462 | if (last && stmt_ends_bb_p (last)) | |
2463 | { | |
2464 | /* If the last statement in the block is the definition | |
2465 | site of the PHI argument, then we can't insert | |
2466 | anything after it. */ | |
2467 | if (TREE_CODE (arg) == SSA_NAME | |
2468 | && SSA_NAME_DEF_STMT (arg) == last) | |
2469 | continue; | |
2470 | } | |
2471 | ||
2472 | /* Create a new instance of the underlying | |
2473 | variable of the PHI result. */ | |
2474 | stmt = build (MODIFY_EXPR, TREE_TYPE (result_var), | |
2475 | NULL, PHI_ARG_DEF (phi, i)); | |
2476 | name = make_ssa_name (result_var, stmt); | |
2477 | TREE_OPERAND (stmt, 0) = name; | |
2478 | ||
2479 | /* Insert the new statement into the block and update | |
2480 | the PHI node. */ | |
2481 | if (last && stmt_ends_bb_p (last)) | |
2482 | bsi_insert_before (&bsi, stmt, BSI_NEW_STMT); | |
2483 | else | |
2484 | bsi_insert_after (&bsi, stmt, BSI_NEW_STMT); | |
06170e1d JL |
2485 | SET_PHI_ARG_DEF (phi, i, name); |
2486 | } | |
2487 | } | |
2488 | } | |
2489 | } | |
2490 | } | |
2491 | ||
6de9cd9a DN |
2492 | /* Take the current function out of SSA form, as described in |
2493 | R. Morgan, ``Building an Optimizing Compiler'', | |
2494 | Butterworth-Heinemann, Boston, MA, 1998. pp 176-186. */ | |
2495 | ||
2496 | static void | |
2497 | rewrite_out_of_ssa (void) | |
2498 | { | |
2499 | var_map map; | |
2500 | int var_flags = 0; | |
35bea171 | 2501 | int ssa_flags = 0; |
6de9cd9a | 2502 | |
06170e1d JL |
2503 | /* If elimination of a PHI requires inserting a copy on a backedge, |
2504 | then we will have to split the backedge which has numerous | |
2505 | undesirable performance effects. | |
2506 | ||
2507 | A significant number of such cases can be handled here by inserting | |
2508 | copies into the loop itself. */ | |
2509 | insert_backedge_copies (); | |
2510 | ||
6de9cd9a DN |
2511 | if (!flag_tree_live_range_split) |
2512 | ssa_flags |= SSANORM_COALESCE_PARTITIONS; | |
2513 | ||
2514 | eliminate_virtual_phis (); | |
2515 | ||
2516 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2517 | dump_tree_cfg (dump_file, dump_flags & ~TDF_DETAILS); | |
2518 | ||
2519 | /* We cannot allow unssa to un-gimplify trees before we instrument them. */ | |
2520 | if (flag_tree_ter && !flag_mudflap) | |
2521 | var_flags = SSA_VAR_MAP_REF_COUNT; | |
2522 | ||
2523 | map = create_ssa_var_map (var_flags); | |
2524 | ||
2525 | if (flag_tree_combine_temps) | |
2526 | ssa_flags |= SSANORM_COMBINE_TEMPS; | |
2527 | if (flag_tree_ter && !flag_mudflap) | |
2528 | ssa_flags |= SSANORM_PERFORM_TER; | |
2529 | ||
2530 | remove_ssa_form (dump_file, map, ssa_flags); | |
2531 | ||
2532 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2533 | dump_tree_cfg (dump_file, dump_flags & ~TDF_DETAILS); | |
2534 | ||
6de9cd9a DN |
2535 | /* Flush out flow graph and SSA data. */ |
2536 | delete_var_map (map); | |
2537 | ||
9885da8e | 2538 | in_ssa_p = false; |
6de9cd9a DN |
2539 | } |
2540 | ||
2541 | ||
2542 | /* Define the parameters of the out of SSA pass. */ | |
2543 | ||
2544 | struct tree_opt_pass pass_del_ssa = | |
2545 | { | |
2546 | "optimized", /* name */ | |
2547 | NULL, /* gate */ | |
2548 | rewrite_out_of_ssa, /* execute */ | |
2549 | NULL, /* sub */ | |
2550 | NULL, /* next */ | |
2551 | 0, /* static_pass_number */ | |
2552 | TV_TREE_SSA_TO_NORMAL, /* tv_id */ | |
c1b763fa | 2553 | PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */ |
6de9cd9a DN |
2554 | 0, /* properties_provided */ |
2555 | /* ??? If TER is enabled, we also kill gimple. */ | |
2556 | PROP_ssa, /* properties_destroyed */ | |
2557 | TODO_verify_ssa | TODO_verify_flow | |
2558 | | TODO_verify_stmts, /* todo_flags_start */ | |
9f8628ba PB |
2559 | TODO_dump_func | TODO_ggc_collect, /* todo_flags_finish */ |
2560 | 0 /* letter */ | |
6de9cd9a | 2561 | }; |