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2862cf88 | 1 | /* Function splitting pass |
d353bf18 | 2 | Copyright (C) 2010-2015 Free Software Foundation, Inc. |
2862cf88 | 3 | Contributed by Jan Hubicka <jh@suse.cz> |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 3, or (at your option) any later | |
10 | version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GCC; see the file COPYING3. If not see | |
19 | <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | /* The purpose of this pass is to split function bodies to improve | |
22 | inlining. I.e. for function of the form: | |
23 | ||
24 | func (...) | |
25 | { | |
26 | if (cheap_test) | |
27 | something_small | |
28 | else | |
29 | something_big | |
30 | } | |
31 | ||
32 | Produce: | |
33 | ||
34 | func.part (...) | |
35 | { | |
36 | something_big | |
37 | } | |
38 | ||
39 | func (...) | |
40 | { | |
41 | if (cheap_test) | |
42 | something_small | |
43 | else | |
44 | func.part (...); | |
45 | } | |
46 | ||
47 | When func becomes inlinable and when cheap_test is often true, inlining func, | |
574c4ab5 | 48 | but not fund.part leads to performance improvement similar as inlining |
2862cf88 | 49 | original func while the code size growth is smaller. |
50 | ||
51 | The pass is organized in three stages: | |
52 | 1) Collect local info about basic block into BB_INFO structure and | |
53 | compute function body estimated size and time. | |
54 | 2) Via DFS walk find all possible basic blocks where we can split | |
55 | and chose best one. | |
56 | 3) If split point is found, split at the specified BB by creating a clone | |
57 | and updating function to call it. | |
58 | ||
59 | The decisions what functions to split are in execute_split_functions | |
60 | and consider_split. | |
61 | ||
62 | There are several possible future improvements for this pass including: | |
63 | ||
64 | 1) Splitting to break up large functions | |
65 | 2) Splitting to reduce stack frame usage | |
66 | 3) Allow split part of function to use values computed in the header part. | |
67 | The values needs to be passed to split function, perhaps via same | |
68 | interface as for nested functions or as argument. | |
69 | 4) Support for simple rematerialization. I.e. when split part use | |
70 | value computed in header from function parameter in very cheap way, we | |
71 | can just recompute it. | |
72 | 5) Support splitting of nested functions. | |
73 | 6) Support non-SSA arguments. | |
74 | 7) There is nothing preventing us from producing multiple parts of single function | |
75 | when needed or splitting also the parts. */ | |
76 | ||
77 | #include "config.h" | |
78 | #include "system.h" | |
79 | #include "coretypes.h" | |
94ea8568 | 80 | #include "hash-set.h" |
81 | #include "machmode.h" | |
b20a8bb4 | 82 | #include "vec.h" |
83 | #include "double-int.h" | |
84 | #include "input.h" | |
85 | #include "alias.h" | |
86 | #include "symtab.h" | |
87 | #include "options.h" | |
88 | #include "wide-int.h" | |
89 | #include "inchash.h" | |
90 | #include "tree.h" | |
91 | #include "fold-const.h" | |
92 | #include "predict.h" | |
94ea8568 | 93 | #include "tm.h" |
94 | #include "hard-reg-set.h" | |
94ea8568 | 95 | #include "function.h" |
96 | #include "dominance.h" | |
97 | #include "cfg.h" | |
98 | #include "cfganal.h" | |
bc61cadb | 99 | #include "basic-block.h" |
100 | #include "tree-ssa-alias.h" | |
101 | #include "internal-fn.h" | |
102 | #include "gimple-expr.h" | |
103 | #include "is-a.h" | |
e795d6e1 | 104 | #include "gimple.h" |
9ed99284 | 105 | #include "stringpool.h" |
d53441c8 | 106 | #include "hashtab.h" |
107 | #include "rtl.h" | |
108 | #include "flags.h" | |
109 | #include "statistics.h" | |
110 | #include "real.h" | |
111 | #include "fixed-value.h" | |
112 | #include "insn-config.h" | |
113 | #include "expmed.h" | |
114 | #include "dojump.h" | |
115 | #include "explow.h" | |
9ed99284 | 116 | #include "calls.h" |
d53441c8 | 117 | #include "emit-rtl.h" |
118 | #include "varasm.h" | |
119 | #include "stmt.h" | |
120 | #include "expr.h" | |
a8783bee | 121 | #include "gimplify.h" |
dcf1a1ec | 122 | #include "gimple-iterator.h" |
e795d6e1 | 123 | #include "gimplify-me.h" |
dcf1a1ec | 124 | #include "gimple-walk.h" |
2862cf88 | 125 | #include "target.h" |
1140c305 | 126 | #include "hash-map.h" |
127 | #include "plugin-api.h" | |
128 | #include "ipa-ref.h" | |
129 | #include "cgraph.h" | |
130 | #include "alloc-pool.h" | |
2cc80ac3 | 131 | #include "symbol-summary.h" |
2862cf88 | 132 | #include "ipa-prop.h" |
073c1fd5 | 133 | #include "gimple-ssa.h" |
134 | #include "tree-cfg.h" | |
135 | #include "tree-phinodes.h" | |
136 | #include "ssa-iterators.h" | |
137 | #include "tree-ssanames.h" | |
138 | #include "tree-into-ssa.h" | |
139 | #include "tree-dfa.h" | |
2862cf88 | 140 | #include "tree-pass.h" |
2862cf88 | 141 | #include "diagnostic.h" |
142 | #include "tree-dump.h" | |
143 | #include "tree-inline.h" | |
2862cf88 | 144 | #include "params.h" |
145 | #include "gimple-pretty-print.h" | |
cbd7f5a0 | 146 | #include "ipa-inline.h" |
f6568ea4 | 147 | #include "cfgloop.h" |
058a1b7a | 148 | #include "tree-chkp.h" |
2862cf88 | 149 | |
150 | /* Per basic block info. */ | |
151 | ||
152 | typedef struct | |
153 | { | |
154 | unsigned int size; | |
155 | unsigned int time; | |
9908fe4d | 156 | } split_bb_info; |
2862cf88 | 157 | |
9908fe4d | 158 | static vec<split_bb_info> bb_info_vec; |
2862cf88 | 159 | |
160 | /* Description of split point. */ | |
161 | ||
162 | struct split_point | |
163 | { | |
164 | /* Size of the partitions. */ | |
165 | unsigned int header_time, header_size, split_time, split_size; | |
166 | ||
574c4ab5 | 167 | /* SSA names that need to be passed into spit function. */ |
2862cf88 | 168 | bitmap ssa_names_to_pass; |
169 | ||
170 | /* Basic block where we split (that will become entry point of new function. */ | |
171 | basic_block entry_bb; | |
172 | ||
173 | /* Basic blocks we are splitting away. */ | |
174 | bitmap split_bbs; | |
b04bab7c | 175 | |
176 | /* True when return value is computed on split part and thus it needs | |
177 | to be returned. */ | |
178 | bool split_part_set_retval; | |
2862cf88 | 179 | }; |
180 | ||
181 | /* Best split point found. */ | |
182 | ||
183 | struct split_point best_split_point; | |
184 | ||
aa2edcb9 | 185 | /* Set of basic blocks that are not allowed to dominate a split point. */ |
186 | ||
187 | static bitmap forbidden_dominators; | |
188 | ||
b04bab7c | 189 | static tree find_retval (basic_block return_bb); |
058a1b7a | 190 | static tree find_retbnd (basic_block return_bb); |
b04bab7c | 191 | |
2dc0a33e | 192 | /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
2862cf88 | 193 | variable, check it if it is present in bitmap passed via DATA. */ |
194 | ||
195 | static bool | |
5b26a9e3 | 196 | test_nonssa_use (gimple, tree t, tree, void *data) |
2862cf88 | 197 | { |
198 | t = get_base_address (t); | |
199 | ||
2dc0a33e | 200 | if (!t || is_gimple_reg (t)) |
201 | return false; | |
202 | ||
203 | if (TREE_CODE (t) == PARM_DECL | |
204 | || (TREE_CODE (t) == VAR_DECL | |
2862cf88 | 205 | && auto_var_in_fn_p (t, current_function_decl)) |
2dc0a33e | 206 | || TREE_CODE (t) == RESULT_DECL |
3c659c08 | 207 | /* Normal labels are part of CFG and will be handled gratefuly. |
208 | Forced labels however can be used directly by statements and | |
209 | need to stay in one partition along with their uses. */ | |
210 | || (TREE_CODE (t) == LABEL_DECL | |
211 | && FORCED_LABEL (t))) | |
2862cf88 | 212 | return bitmap_bit_p ((bitmap)data, DECL_UID (t)); |
b04bab7c | 213 | |
2dc0a33e | 214 | /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
215 | to pretend that the value pointed to is actual result decl. */ | |
216 | if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) | |
b04bab7c | 217 | && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
ec11736b | 218 | && SSA_NAME_VAR (TREE_OPERAND (t, 0)) |
b04bab7c | 219 | && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL |
220 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
2dc0a33e | 221 | return |
222 | bitmap_bit_p ((bitmap)data, | |
223 | DECL_UID (DECL_RESULT (current_function_decl))); | |
224 | ||
2862cf88 | 225 | return false; |
226 | } | |
227 | ||
228 | /* Dump split point CURRENT. */ | |
229 | ||
230 | static void | |
231 | dump_split_point (FILE * file, struct split_point *current) | |
232 | { | |
233 | fprintf (file, | |
1d0b727d | 234 | "Split point at BB %i\n" |
235 | " header time: %i header size: %i\n" | |
236 | " split time: %i split size: %i\n bbs: ", | |
2862cf88 | 237 | current->entry_bb->index, current->header_time, |
238 | current->header_size, current->split_time, current->split_size); | |
239 | dump_bitmap (file, current->split_bbs); | |
240 | fprintf (file, " SSA names to pass: "); | |
241 | dump_bitmap (file, current->ssa_names_to_pass); | |
242 | } | |
243 | ||
2dc0a33e | 244 | /* Look for all BBs in header that might lead to the split part and verify |
245 | that they are not defining any non-SSA var used by the split part. | |
4493dab3 | 246 | Parameters are the same as for consider_split. */ |
247 | ||
248 | static bool | |
249 | verify_non_ssa_vars (struct split_point *current, bitmap non_ssa_vars, | |
250 | basic_block return_bb) | |
251 | { | |
252 | bitmap seen = BITMAP_ALLOC (NULL); | |
1e094109 | 253 | vec<basic_block> worklist = vNULL; |
4493dab3 | 254 | edge e; |
255 | edge_iterator ei; | |
256 | bool ok = true; | |
3c659c08 | 257 | basic_block bb; |
2dc0a33e | 258 | |
4493dab3 | 259 | FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
34154e27 | 260 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4493dab3 | 261 | && !bitmap_bit_p (current->split_bbs, e->src->index)) |
262 | { | |
f1f41a6c | 263 | worklist.safe_push (e->src); |
4493dab3 | 264 | bitmap_set_bit (seen, e->src->index); |
265 | } | |
2dc0a33e | 266 | |
f1f41a6c | 267 | while (!worklist.is_empty ()) |
4493dab3 | 268 | { |
3c659c08 | 269 | bb = worklist.pop (); |
4493dab3 | 270 | FOR_EACH_EDGE (e, ei, bb->preds) |
34154e27 | 271 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
6ef9bbe0 | 272 | && bitmap_set_bit (seen, e->src->index)) |
4493dab3 | 273 | { |
274 | gcc_checking_assert (!bitmap_bit_p (current->split_bbs, | |
275 | e->src->index)); | |
f1f41a6c | 276 | worklist.safe_push (e->src); |
4493dab3 | 277 | } |
1a91d914 | 278 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); |
279 | gsi_next (&bsi)) | |
4493dab3 | 280 | { |
2dc0a33e | 281 | gimple stmt = gsi_stmt (bsi); |
282 | if (is_gimple_debug (stmt)) | |
4493dab3 | 283 | continue; |
284 | if (walk_stmt_load_store_addr_ops | |
2dc0a33e | 285 | (stmt, non_ssa_vars, test_nonssa_use, test_nonssa_use, |
286 | test_nonssa_use)) | |
4493dab3 | 287 | { |
288 | ok = false; | |
289 | goto done; | |
290 | } | |
1a91d914 | 291 | if (glabel *label_stmt = dyn_cast <glabel *> (stmt)) |
292 | if (test_nonssa_use (stmt, gimple_label_label (label_stmt), | |
293 | NULL_TREE, non_ssa_vars)) | |
294 | { | |
295 | ok = false; | |
296 | goto done; | |
297 | } | |
4493dab3 | 298 | } |
1a91d914 | 299 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); |
300 | gsi_next (&bsi)) | |
4493dab3 | 301 | { |
302 | if (walk_stmt_load_store_addr_ops | |
2dc0a33e | 303 | (gsi_stmt (bsi), non_ssa_vars, test_nonssa_use, test_nonssa_use, |
304 | test_nonssa_use)) | |
4493dab3 | 305 | { |
306 | ok = false; | |
307 | goto done; | |
308 | } | |
309 | } | |
310 | FOR_EACH_EDGE (e, ei, bb->succs) | |
311 | { | |
312 | if (e->dest != return_bb) | |
313 | continue; | |
1a91d914 | 314 | for (gphi_iterator bsi = gsi_start_phis (return_bb); |
315 | !gsi_end_p (bsi); | |
4493dab3 | 316 | gsi_next (&bsi)) |
317 | { | |
1a91d914 | 318 | gphi *stmt = bsi.phi (); |
4493dab3 | 319 | tree op = gimple_phi_arg_def (stmt, e->dest_idx); |
320 | ||
7c782c9b | 321 | if (virtual_operand_p (gimple_phi_result (stmt))) |
4493dab3 | 322 | continue; |
323 | if (TREE_CODE (op) != SSA_NAME | |
5b26a9e3 | 324 | && test_nonssa_use (stmt, op, op, non_ssa_vars)) |
4493dab3 | 325 | { |
326 | ok = false; | |
327 | goto done; | |
328 | } | |
329 | } | |
330 | } | |
331 | } | |
3c659c08 | 332 | |
333 | /* Verify that the rest of function does not define any label | |
334 | used by the split part. */ | |
335 | FOR_EACH_BB_FN (bb, cfun) | |
336 | if (!bitmap_bit_p (current->split_bbs, bb->index) | |
337 | && !bitmap_bit_p (seen, bb->index)) | |
338 | { | |
339 | gimple_stmt_iterator bsi; | |
340 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1a91d914 | 341 | if (glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (bsi))) |
3c659c08 | 342 | { |
1a91d914 | 343 | if (test_nonssa_use (label_stmt, |
344 | gimple_label_label (label_stmt), | |
345 | NULL_TREE, non_ssa_vars)) | |
346 | { | |
347 | ok = false; | |
348 | goto done; | |
349 | } | |
3c659c08 | 350 | } |
1a91d914 | 351 | else |
3c659c08 | 352 | break; |
353 | } | |
354 | ||
4493dab3 | 355 | done: |
356 | BITMAP_FREE (seen); | |
f1f41a6c | 357 | worklist.release (); |
4493dab3 | 358 | return ok; |
359 | } | |
360 | ||
aa2edcb9 | 361 | /* If STMT is a call, check the callee against a list of forbidden |
362 | predicate functions. If a match is found, look for uses of the | |
363 | call result in condition statements that compare against zero. | |
364 | For each such use, find the block targeted by the condition | |
365 | statement for the nonzero result, and set the bit for this block | |
366 | in the forbidden dominators bitmap. The purpose of this is to avoid | |
367 | selecting a split point where we are likely to lose the chance | |
368 | to optimize away an unused function call. */ | |
369 | ||
370 | static void | |
371 | check_forbidden_calls (gimple stmt) | |
372 | { | |
373 | imm_use_iterator use_iter; | |
374 | use_operand_p use_p; | |
375 | tree lhs; | |
376 | ||
377 | /* At the moment, __builtin_constant_p is the only forbidden | |
378 | predicate function call (see PR49642). */ | |
379 | if (!gimple_call_builtin_p (stmt, BUILT_IN_CONSTANT_P)) | |
380 | return; | |
381 | ||
382 | lhs = gimple_call_lhs (stmt); | |
383 | ||
384 | if (!lhs || TREE_CODE (lhs) != SSA_NAME) | |
385 | return; | |
386 | ||
387 | FOR_EACH_IMM_USE_FAST (use_p, use_iter, lhs) | |
388 | { | |
389 | tree op1; | |
390 | basic_block use_bb, forbidden_bb; | |
391 | enum tree_code code; | |
392 | edge true_edge, false_edge; | |
1a91d914 | 393 | gcond *use_stmt; |
aa2edcb9 | 394 | |
1a91d914 | 395 | use_stmt = dyn_cast <gcond *> (USE_STMT (use_p)); |
396 | if (!use_stmt) | |
aa2edcb9 | 397 | continue; |
398 | ||
399 | /* Assuming canonical form for GIMPLE_COND here, with constant | |
400 | in second position. */ | |
401 | op1 = gimple_cond_rhs (use_stmt); | |
402 | code = gimple_cond_code (use_stmt); | |
403 | use_bb = gimple_bb (use_stmt); | |
404 | ||
405 | extract_true_false_edges_from_block (use_bb, &true_edge, &false_edge); | |
406 | ||
407 | /* We're only interested in comparisons that distinguish | |
408 | unambiguously from zero. */ | |
409 | if (!integer_zerop (op1) || code == LE_EXPR || code == GE_EXPR) | |
410 | continue; | |
411 | ||
412 | if (code == EQ_EXPR) | |
413 | forbidden_bb = false_edge->dest; | |
414 | else | |
415 | forbidden_bb = true_edge->dest; | |
416 | ||
417 | bitmap_set_bit (forbidden_dominators, forbidden_bb->index); | |
418 | } | |
419 | } | |
420 | ||
421 | /* If BB is dominated by any block in the forbidden dominators set, | |
422 | return TRUE; else FALSE. */ | |
423 | ||
424 | static bool | |
425 | dominated_by_forbidden (basic_block bb) | |
426 | { | |
427 | unsigned dom_bb; | |
428 | bitmap_iterator bi; | |
429 | ||
430 | EXECUTE_IF_SET_IN_BITMAP (forbidden_dominators, 1, dom_bb, bi) | |
431 | { | |
f5a6b05f | 432 | if (dominated_by_p (CDI_DOMINATORS, bb, |
433 | BASIC_BLOCK_FOR_FN (cfun, dom_bb))) | |
aa2edcb9 | 434 | return true; |
435 | } | |
436 | ||
437 | return false; | |
438 | } | |
439 | ||
058a1b7a | 440 | /* For give split point CURRENT and return block RETURN_BB return 1 |
441 | if ssa name VAL is set by split part and 0 otherwise. */ | |
442 | static bool | |
443 | split_part_set_ssa_name_p (tree val, struct split_point *current, | |
444 | basic_block return_bb) | |
445 | { | |
446 | if (TREE_CODE (val) != SSA_NAME) | |
447 | return false; | |
448 | ||
449 | return (!SSA_NAME_IS_DEFAULT_DEF (val) | |
450 | && (bitmap_bit_p (current->split_bbs, | |
451 | gimple_bb (SSA_NAME_DEF_STMT (val))->index) | |
452 | || gimple_bb (SSA_NAME_DEF_STMT (val)) == return_bb)); | |
453 | } | |
454 | ||
2862cf88 | 455 | /* We found an split_point CURRENT. NON_SSA_VARS is bitmap of all non ssa |
456 | variables used and RETURN_BB is return basic block. | |
457 | See if we can split function here. */ | |
458 | ||
459 | static void | |
460 | consider_split (struct split_point *current, bitmap non_ssa_vars, | |
461 | basic_block return_bb) | |
462 | { | |
463 | tree parm; | |
464 | unsigned int num_args = 0; | |
465 | unsigned int call_overhead; | |
466 | edge e; | |
467 | edge_iterator ei; | |
1a91d914 | 468 | gphi_iterator bsi; |
6a69e813 | 469 | unsigned int i; |
574c4ab5 | 470 | int incoming_freq = 0; |
b04bab7c | 471 | tree retval; |
058a1b7a | 472 | tree retbnd; |
15ca8f90 | 473 | bool back_edge = false; |
6a69e813 | 474 | |
2862cf88 | 475 | if (dump_file && (dump_flags & TDF_DETAILS)) |
476 | dump_split_point (dump_file, current); | |
477 | ||
6a69e813 | 478 | FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
15ca8f90 | 479 | { |
480 | if (e->flags & EDGE_DFS_BACK) | |
481 | back_edge = true; | |
482 | if (!bitmap_bit_p (current->split_bbs, e->src->index)) | |
483 | incoming_freq += EDGE_FREQUENCY (e); | |
484 | } | |
6a69e813 | 485 | |
2862cf88 | 486 | /* Do not split when we would end up calling function anyway. */ |
574c4ab5 | 487 | if (incoming_freq |
34154e27 | 488 | >= (ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency |
2862cf88 | 489 | * PARAM_VALUE (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY) / 100)) |
490 | { | |
15ca8f90 | 491 | /* When profile is guessed, we can not expect it to give us |
492 | realistic estimate on likelyness of function taking the | |
493 | complex path. As a special case, when tail of the function is | |
494 | a loop, enable splitting since inlining code skipping the loop | |
495 | is likely noticeable win. */ | |
496 | if (back_edge | |
f26d8580 | 497 | && profile_status_for_fn (cfun) != PROFILE_READ |
34154e27 | 498 | && incoming_freq < ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency) |
15ca8f90 | 499 | { |
500 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
501 | fprintf (dump_file, | |
502 | " Split before loop, accepting despite low frequencies %i %i.\n", | |
503 | incoming_freq, | |
34154e27 | 504 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency); |
15ca8f90 | 505 | } |
506 | else | |
507 | { | |
508 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
509 | fprintf (dump_file, | |
510 | " Refused: incoming frequency is too large.\n"); | |
511 | return; | |
512 | } | |
2862cf88 | 513 | } |
514 | ||
515 | if (!current->header_size) | |
516 | { | |
517 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
518 | fprintf (dump_file, " Refused: header empty\n"); | |
2862cf88 | 519 | return; |
520 | } | |
521 | ||
574c4ab5 | 522 | /* Verify that PHI args on entry are either virtual or all their operands |
523 | incoming from header are the same. */ | |
6a69e813 | 524 | for (bsi = gsi_start_phis (current->entry_bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
2862cf88 | 525 | { |
1a91d914 | 526 | gphi *stmt = bsi.phi (); |
6a69e813 | 527 | tree val = NULL; |
528 | ||
7c782c9b | 529 | if (virtual_operand_p (gimple_phi_result (stmt))) |
6a69e813 | 530 | continue; |
531 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
532 | { | |
533 | edge e = gimple_phi_arg_edge (stmt, i); | |
534 | if (!bitmap_bit_p (current->split_bbs, e->src->index)) | |
535 | { | |
536 | tree edge_val = gimple_phi_arg_def (stmt, i); | |
537 | if (val && edge_val != val) | |
538 | { | |
539 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
540 | fprintf (dump_file, | |
541 | " Refused: entry BB has PHI with multiple variants\n"); | |
542 | return; | |
543 | } | |
544 | val = edge_val; | |
545 | } | |
546 | } | |
2862cf88 | 547 | } |
548 | ||
549 | ||
550 | /* See what argument we will pass to the split function and compute | |
551 | call overhead. */ | |
552 | call_overhead = eni_size_weights.call_cost; | |
553 | for (parm = DECL_ARGUMENTS (current_function_decl); parm; | |
1767a056 | 554 | parm = DECL_CHAIN (parm)) |
2862cf88 | 555 | { |
556 | if (!is_gimple_reg (parm)) | |
557 | { | |
558 | if (bitmap_bit_p (non_ssa_vars, DECL_UID (parm))) | |
559 | { | |
560 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
561 | fprintf (dump_file, | |
562 | " Refused: need to pass non-ssa param values\n"); | |
563 | return; | |
564 | } | |
565 | } | |
c6dfe037 | 566 | else |
2862cf88 | 567 | { |
c6dfe037 | 568 | tree ddef = ssa_default_def (cfun, parm); |
569 | if (ddef | |
570 | && bitmap_bit_p (current->ssa_names_to_pass, | |
571 | SSA_NAME_VERSION (ddef))) | |
572 | { | |
573 | if (!VOID_TYPE_P (TREE_TYPE (parm))) | |
96c7c99c | 574 | call_overhead += estimate_move_cost (TREE_TYPE (parm), false); |
c6dfe037 | 575 | num_args++; |
576 | } | |
2862cf88 | 577 | } |
578 | } | |
579 | if (!VOID_TYPE_P (TREE_TYPE (current_function_decl))) | |
96c7c99c | 580 | call_overhead += estimate_move_cost (TREE_TYPE (current_function_decl), |
581 | false); | |
2862cf88 | 582 | |
583 | if (current->split_size <= call_overhead) | |
584 | { | |
585 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
586 | fprintf (dump_file, | |
587 | " Refused: split size is smaller than call overhead\n"); | |
588 | return; | |
589 | } | |
590 | if (current->header_size + call_overhead | |
591 | >= (unsigned int)(DECL_DECLARED_INLINE_P (current_function_decl) | |
592 | ? MAX_INLINE_INSNS_SINGLE | |
593 | : MAX_INLINE_INSNS_AUTO)) | |
594 | { | |
595 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
596 | fprintf (dump_file, | |
597 | " Refused: header size is too large for inline candidate\n"); | |
598 | return; | |
599 | } | |
600 | ||
601 | /* FIXME: we currently can pass only SSA function parameters to the split | |
fd8d648f | 602 | arguments. Once parm_adjustment infrastructure is supported by cloning, |
2862cf88 | 603 | we can pass more than that. */ |
604 | if (num_args != bitmap_count_bits (current->ssa_names_to_pass)) | |
605 | { | |
6a69e813 | 606 | |
2862cf88 | 607 | if (dump_file && (dump_flags & TDF_DETAILS)) |
608 | fprintf (dump_file, | |
609 | " Refused: need to pass non-param values\n"); | |
610 | return; | |
611 | } | |
612 | ||
613 | /* When there are non-ssa vars used in the split region, see if they | |
614 | are used in the header region. If so, reject the split. | |
615 | FIXME: we can use nested function support to access both. */ | |
4493dab3 | 616 | if (!bitmap_empty_p (non_ssa_vars) |
617 | && !verify_non_ssa_vars (current, non_ssa_vars, return_bb)) | |
2862cf88 | 618 | { |
4493dab3 | 619 | if (dump_file && (dump_flags & TDF_DETAILS)) |
620 | fprintf (dump_file, | |
621 | " Refused: split part has non-ssa uses\n"); | |
2862cf88 | 622 | return; |
623 | } | |
aa2edcb9 | 624 | |
625 | /* If the split point is dominated by a forbidden block, reject | |
626 | the split. */ | |
627 | if (!bitmap_empty_p (forbidden_dominators) | |
628 | && dominated_by_forbidden (current->entry_bb)) | |
629 | { | |
630 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
631 | fprintf (dump_file, | |
632 | " Refused: split point dominated by forbidden block\n"); | |
633 | return; | |
634 | } | |
635 | ||
b04bab7c | 636 | /* See if retval used by return bb is computed by header or split part. |
637 | When it is computed by split part, we need to produce return statement | |
638 | in the split part and add code to header to pass it around. | |
639 | ||
640 | This is bit tricky to test: | |
641 | 1) When there is no return_bb or no return value, we always pass | |
642 | value around. | |
643 | 2) Invariants are always computed by caller. | |
644 | 3) For SSA we need to look if defining statement is in header or split part | |
645 | 4) For non-SSA we need to look where the var is computed. */ | |
646 | retval = find_retval (return_bb); | |
647 | if (!retval) | |
648 | current->split_part_set_retval = true; | |
649 | else if (is_gimple_min_invariant (retval)) | |
650 | current->split_part_set_retval = false; | |
651 | /* Special case is value returned by reference we record as if it was non-ssa | |
652 | set to result_decl. */ | |
653 | else if (TREE_CODE (retval) == SSA_NAME | |
ec11736b | 654 | && SSA_NAME_VAR (retval) |
b04bab7c | 655 | && TREE_CODE (SSA_NAME_VAR (retval)) == RESULT_DECL |
656 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
657 | current->split_part_set_retval | |
658 | = bitmap_bit_p (non_ssa_vars, DECL_UID (SSA_NAME_VAR (retval))); | |
659 | else if (TREE_CODE (retval) == SSA_NAME) | |
660 | current->split_part_set_retval | |
058a1b7a | 661 | = split_part_set_ssa_name_p (retval, current, return_bb); |
b04bab7c | 662 | else if (TREE_CODE (retval) == PARM_DECL) |
663 | current->split_part_set_retval = false; | |
664 | else if (TREE_CODE (retval) == VAR_DECL | |
665 | || TREE_CODE (retval) == RESULT_DECL) | |
666 | current->split_part_set_retval | |
667 | = bitmap_bit_p (non_ssa_vars, DECL_UID (retval)); | |
668 | else | |
669 | current->split_part_set_retval = true; | |
670 | ||
058a1b7a | 671 | /* See if retbnd used by return bb is computed by header or split part. */ |
672 | retbnd = find_retbnd (return_bb); | |
673 | if (retbnd) | |
674 | { | |
675 | bool split_part_set_retbnd | |
676 | = split_part_set_ssa_name_p (retbnd, current, return_bb); | |
677 | ||
678 | /* If we have both return value and bounds then keep their definitions | |
679 | in a single function. We use SSA names to link returned bounds and | |
680 | value and therefore do not handle cases when result is passed by | |
681 | reference (which should not be our case anyway since bounds are | |
682 | returned for pointers only). */ | |
683 | if ((DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)) | |
684 | && current->split_part_set_retval) | |
685 | || split_part_set_retbnd != current->split_part_set_retval) | |
686 | { | |
687 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
688 | fprintf (dump_file, | |
689 | " Refused: split point splits return value and bounds\n"); | |
690 | return; | |
691 | } | |
692 | } | |
693 | ||
9aa9c1e6 | 694 | /* split_function fixes up at most one PHI non-virtual PHI node in return_bb, |
695 | for the return value. If there are other PHIs, give up. */ | |
34154e27 | 696 | if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
9aa9c1e6 | 697 | { |
1a91d914 | 698 | gphi_iterator psi; |
9aa9c1e6 | 699 | |
700 | for (psi = gsi_start_phis (return_bb); !gsi_end_p (psi); gsi_next (&psi)) | |
1a91d914 | 701 | if (!virtual_operand_p (gimple_phi_result (psi.phi ())) |
9aa9c1e6 | 702 | && !(retval |
703 | && current->split_part_set_retval | |
704 | && TREE_CODE (retval) == SSA_NAME | |
705 | && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)) | |
1a91d914 | 706 | && SSA_NAME_DEF_STMT (retval) == psi.phi ())) |
9aa9c1e6 | 707 | { |
708 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
709 | fprintf (dump_file, | |
710 | " Refused: return bb has extra PHIs\n"); | |
711 | return; | |
712 | } | |
713 | } | |
714 | ||
715 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
716 | fprintf (dump_file, " Accepted!\n"); | |
717 | ||
2862cf88 | 718 | /* At the moment chose split point with lowest frequency and that leaves |
719 | out smallest size of header. | |
720 | In future we might re-consider this heuristics. */ | |
721 | if (!best_split_point.split_bbs | |
722 | || best_split_point.entry_bb->frequency > current->entry_bb->frequency | |
723 | || (best_split_point.entry_bb->frequency == current->entry_bb->frequency | |
724 | && best_split_point.split_size < current->split_size)) | |
725 | ||
726 | { | |
727 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
728 | fprintf (dump_file, " New best split point!\n"); | |
729 | if (best_split_point.ssa_names_to_pass) | |
730 | { | |
731 | BITMAP_FREE (best_split_point.ssa_names_to_pass); | |
732 | BITMAP_FREE (best_split_point.split_bbs); | |
733 | } | |
734 | best_split_point = *current; | |
735 | best_split_point.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
736 | bitmap_copy (best_split_point.ssa_names_to_pass, | |
737 | current->ssa_names_to_pass); | |
738 | best_split_point.split_bbs = BITMAP_ALLOC (NULL); | |
739 | bitmap_copy (best_split_point.split_bbs, current->split_bbs); | |
740 | } | |
741 | } | |
742 | ||
4493dab3 | 743 | /* Return basic block containing RETURN statement. We allow basic blocks |
744 | of the form: | |
745 | <retval> = tmp_var; | |
746 | return <retval> | |
747 | but return_bb can not be more complex than this. | |
efee62d1 | 748 | If nothing is found, return the exit block. |
4493dab3 | 749 | |
2862cf88 | 750 | When there are multiple RETURN statement, chose one with return value, |
751 | since that one is more likely shared by multiple code paths. | |
4493dab3 | 752 | |
753 | Return BB is special, because for function splitting it is the only | |
754 | basic block that is duplicated in between header and split part of the | |
755 | function. | |
756 | ||
2862cf88 | 757 | TODO: We might support multiple return blocks. */ |
758 | ||
759 | static basic_block | |
760 | find_return_bb (void) | |
761 | { | |
762 | edge e; | |
34154e27 | 763 | basic_block return_bb = EXIT_BLOCK_PTR_FOR_FN (cfun); |
b234c94d | 764 | gimple_stmt_iterator bsi; |
765 | bool found_return = false; | |
766 | tree retval = NULL_TREE; | |
2862cf88 | 767 | |
34154e27 | 768 | if (!single_pred_p (EXIT_BLOCK_PTR_FOR_FN (cfun))) |
b234c94d | 769 | return return_bb; |
770 | ||
34154e27 | 771 | e = single_pred_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)); |
b234c94d | 772 | for (bsi = gsi_last_bb (e->src); !gsi_end_p (bsi); gsi_prev (&bsi)) |
773 | { | |
774 | gimple stmt = gsi_stmt (bsi); | |
1a3c6423 | 775 | if (gimple_code (stmt) == GIMPLE_LABEL |
776 | || is_gimple_debug (stmt) | |
777 | || gimple_clobber_p (stmt)) | |
b234c94d | 778 | ; |
779 | else if (gimple_code (stmt) == GIMPLE_ASSIGN | |
780 | && found_return | |
781 | && gimple_assign_single_p (stmt) | |
782 | && (auto_var_in_fn_p (gimple_assign_rhs1 (stmt), | |
783 | current_function_decl) | |
784 | || is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) | |
785 | && retval == gimple_assign_lhs (stmt)) | |
786 | ; | |
1a91d914 | 787 | else if (greturn *return_stmt = dyn_cast <greturn *> (stmt)) |
b234c94d | 788 | { |
789 | found_return = true; | |
1a91d914 | 790 | retval = gimple_return_retval (return_stmt); |
b234c94d | 791 | } |
792 | else | |
793 | break; | |
794 | } | |
795 | if (gsi_end_p (bsi) && found_return) | |
796 | return_bb = e->src; | |
2862cf88 | 797 | |
2862cf88 | 798 | return return_bb; |
799 | } | |
800 | ||
574c4ab5 | 801 | /* Given return basic block RETURN_BB, see where return value is really |
4493dab3 | 802 | stored. */ |
803 | static tree | |
804 | find_retval (basic_block return_bb) | |
805 | { | |
806 | gimple_stmt_iterator bsi; | |
807 | for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1a91d914 | 808 | if (greturn *return_stmt = dyn_cast <greturn *> (gsi_stmt (bsi))) |
809 | return gimple_return_retval (return_stmt); | |
1a3c6423 | 810 | else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN |
811 | && !gimple_clobber_p (gsi_stmt (bsi))) | |
4493dab3 | 812 | return gimple_assign_rhs1 (gsi_stmt (bsi)); |
813 | return NULL; | |
814 | } | |
815 | ||
058a1b7a | 816 | /* Given return basic block RETURN_BB, see where return bounds are really |
817 | stored. */ | |
818 | static tree | |
819 | find_retbnd (basic_block return_bb) | |
820 | { | |
821 | gimple_stmt_iterator bsi; | |
822 | for (bsi = gsi_last_bb (return_bb); !gsi_end_p (bsi); gsi_prev (&bsi)) | |
823 | if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) | |
824 | return gimple_return_retbnd (gsi_stmt (bsi)); | |
825 | return NULL; | |
826 | } | |
827 | ||
2dc0a33e | 828 | /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
829 | variable, mark it as used in bitmap passed via DATA. | |
2862cf88 | 830 | Return true when access to T prevents splitting the function. */ |
831 | ||
832 | static bool | |
5b26a9e3 | 833 | mark_nonssa_use (gimple, tree t, tree, void *data) |
2862cf88 | 834 | { |
835 | t = get_base_address (t); | |
836 | ||
837 | if (!t || is_gimple_reg (t)) | |
838 | return false; | |
839 | ||
840 | /* At present we can't pass non-SSA arguments to split function. | |
841 | FIXME: this can be relaxed by passing references to arguments. */ | |
842 | if (TREE_CODE (t) == PARM_DECL) | |
843 | { | |
844 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2dc0a33e | 845 | fprintf (dump_file, |
846 | "Cannot split: use of non-ssa function parameter.\n"); | |
2862cf88 | 847 | return true; |
848 | } | |
849 | ||
2dc0a33e | 850 | if ((TREE_CODE (t) == VAR_DECL |
851 | && auto_var_in_fn_p (t, current_function_decl)) | |
852 | || TREE_CODE (t) == RESULT_DECL | |
3c659c08 | 853 | || (TREE_CODE (t) == LABEL_DECL |
854 | && FORCED_LABEL (t))) | |
2862cf88 | 855 | bitmap_set_bit ((bitmap)data, DECL_UID (t)); |
b04bab7c | 856 | |
2dc0a33e | 857 | /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
858 | to pretend that the value pointed to is actual result decl. */ | |
859 | if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) | |
b04bab7c | 860 | && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
ec11736b | 861 | && SSA_NAME_VAR (TREE_OPERAND (t, 0)) |
b04bab7c | 862 | && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL |
863 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
2dc0a33e | 864 | return |
865 | bitmap_bit_p ((bitmap)data, | |
866 | DECL_UID (DECL_RESULT (current_function_decl))); | |
867 | ||
2862cf88 | 868 | return false; |
869 | } | |
870 | ||
871 | /* Compute local properties of basic block BB we collect when looking for | |
872 | split points. We look for ssa defs and store them in SET_SSA_NAMES, | |
873 | for ssa uses and store them in USED_SSA_NAMES and for any non-SSA automatic | |
874 | vars stored in NON_SSA_VARS. | |
875 | ||
876 | When BB has edge to RETURN_BB, collect uses in RETURN_BB too. | |
877 | ||
878 | Return false when BB contains something that prevents it from being put into | |
879 | split function. */ | |
880 | ||
881 | static bool | |
882 | visit_bb (basic_block bb, basic_block return_bb, | |
883 | bitmap set_ssa_names, bitmap used_ssa_names, | |
884 | bitmap non_ssa_vars) | |
885 | { | |
2862cf88 | 886 | edge e; |
887 | edge_iterator ei; | |
888 | bool can_split = true; | |
889 | ||
1a91d914 | 890 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); |
891 | gsi_next (&bsi)) | |
2862cf88 | 892 | { |
893 | gimple stmt = gsi_stmt (bsi); | |
894 | tree op; | |
895 | ssa_op_iter iter; | |
896 | tree decl; | |
897 | ||
898 | if (is_gimple_debug (stmt)) | |
899 | continue; | |
900 | ||
1a3c6423 | 901 | if (gimple_clobber_p (stmt)) |
902 | continue; | |
903 | ||
2862cf88 | 904 | /* FIXME: We can split regions containing EH. We can not however |
905 | split RESX, EH_DISPATCH and EH_POINTER referring to same region | |
906 | into different partitions. This would require tracking of | |
907 | EH regions and checking in consider_split_point if they | |
908 | are not used elsewhere. */ | |
892c141e | 909 | if (gimple_code (stmt) == GIMPLE_RESX) |
2862cf88 | 910 | { |
911 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
892c141e | 912 | fprintf (dump_file, "Cannot split: resx.\n"); |
2862cf88 | 913 | can_split = false; |
914 | } | |
915 | if (gimple_code (stmt) == GIMPLE_EH_DISPATCH) | |
916 | { | |
917 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2dc0a33e | 918 | fprintf (dump_file, "Cannot split: eh dispatch.\n"); |
2862cf88 | 919 | can_split = false; |
920 | } | |
921 | ||
922 | /* Check builtins that prevent splitting. */ | |
923 | if (gimple_code (stmt) == GIMPLE_CALL | |
924 | && (decl = gimple_call_fndecl (stmt)) != NULL_TREE | |
925 | && DECL_BUILT_IN (decl) | |
926 | && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL) | |
927 | switch (DECL_FUNCTION_CODE (decl)) | |
928 | { | |
929 | /* FIXME: once we will allow passing non-parm values to split part, | |
930 | we need to be sure to handle correct builtin_stack_save and | |
931 | builtin_stack_restore. At the moment we are safe; there is no | |
932 | way to store builtin_stack_save result in non-SSA variable | |
933 | since all calls to those are compiler generated. */ | |
934 | case BUILT_IN_APPLY: | |
3c97c75d | 935 | case BUILT_IN_APPLY_ARGS: |
2862cf88 | 936 | case BUILT_IN_VA_START: |
937 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2dc0a33e | 938 | fprintf (dump_file, |
939 | "Cannot split: builtin_apply and va_start.\n"); | |
2862cf88 | 940 | can_split = false; |
941 | break; | |
942 | case BUILT_IN_EH_POINTER: | |
943 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2dc0a33e | 944 | fprintf (dump_file, "Cannot split: builtin_eh_pointer.\n"); |
2862cf88 | 945 | can_split = false; |
946 | break; | |
947 | default: | |
948 | break; | |
949 | } | |
950 | ||
951 | FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF) | |
952 | bitmap_set_bit (set_ssa_names, SSA_NAME_VERSION (op)); | |
953 | FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE) | |
954 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
955 | can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, | |
956 | mark_nonssa_use, | |
957 | mark_nonssa_use, | |
958 | mark_nonssa_use); | |
959 | } | |
1a91d914 | 960 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); |
961 | gsi_next (&bsi)) | |
2862cf88 | 962 | { |
1a91d914 | 963 | gphi *stmt = bsi.phi (); |
6a69e813 | 964 | unsigned int i; |
2862cf88 | 965 | |
7c782c9b | 966 | if (virtual_operand_p (gimple_phi_result (stmt))) |
2862cf88 | 967 | continue; |
6a69e813 | 968 | bitmap_set_bit (set_ssa_names, |
969 | SSA_NAME_VERSION (gimple_phi_result (stmt))); | |
970 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
971 | { | |
972 | tree op = gimple_phi_arg_def (stmt, i); | |
973 | if (TREE_CODE (op) == SSA_NAME) | |
974 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
975 | } | |
2862cf88 | 976 | can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, |
977 | mark_nonssa_use, | |
978 | mark_nonssa_use, | |
979 | mark_nonssa_use); | |
980 | } | |
574c4ab5 | 981 | /* Record also uses coming from PHI operand in return BB. */ |
2862cf88 | 982 | FOR_EACH_EDGE (e, ei, bb->succs) |
983 | if (e->dest == return_bb) | |
984 | { | |
1a91d914 | 985 | for (gphi_iterator bsi = gsi_start_phis (return_bb); |
986 | !gsi_end_p (bsi); | |
987 | gsi_next (&bsi)) | |
2862cf88 | 988 | { |
1a91d914 | 989 | gphi *stmt = bsi.phi (); |
2862cf88 | 990 | tree op = gimple_phi_arg_def (stmt, e->dest_idx); |
991 | ||
7c782c9b | 992 | if (virtual_operand_p (gimple_phi_result (stmt))) |
2862cf88 | 993 | continue; |
2862cf88 | 994 | if (TREE_CODE (op) == SSA_NAME) |
995 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
996 | else | |
5b26a9e3 | 997 | can_split &= !mark_nonssa_use (stmt, op, op, non_ssa_vars); |
2862cf88 | 998 | } |
2862cf88 | 999 | } |
1000 | return can_split; | |
1001 | } | |
1002 | ||
1003 | /* Stack entry for recursive DFS walk in find_split_point. */ | |
1004 | ||
1005 | typedef struct | |
1006 | { | |
1007 | /* Basic block we are examining. */ | |
1008 | basic_block bb; | |
1009 | ||
1010 | /* SSA names set and used by the BB and all BBs reachable | |
1011 | from it via DFS walk. */ | |
1012 | bitmap set_ssa_names, used_ssa_names; | |
1013 | bitmap non_ssa_vars; | |
1014 | ||
1015 | /* All BBS visited from this BB via DFS walk. */ | |
1016 | bitmap bbs_visited; | |
1017 | ||
1018 | /* Last examined edge in DFS walk. Since we walk unoriented graph, | |
574c4ab5 | 1019 | the value is up to sum of incoming and outgoing edges of BB. */ |
2862cf88 | 1020 | unsigned int edge_num; |
1021 | ||
1022 | /* Stack entry index of earliest BB reachable from current BB | |
574c4ab5 | 1023 | or any BB visited later in DFS walk. */ |
2862cf88 | 1024 | int earliest; |
1025 | ||
1026 | /* Overall time and size of all BBs reached from this BB in DFS walk. */ | |
1027 | int overall_time, overall_size; | |
1028 | ||
1029 | /* When false we can not split on this BB. */ | |
1030 | bool can_split; | |
1031 | } stack_entry; | |
2862cf88 | 1032 | |
1033 | ||
1034 | /* Find all articulations and call consider_split on them. | |
1035 | OVERALL_TIME and OVERALL_SIZE is time and size of the function. | |
1036 | ||
1037 | We perform basic algorithm for finding an articulation in a graph | |
1038 | created from CFG by considering it to be an unoriented graph. | |
1039 | ||
1040 | The articulation is discovered via DFS walk. We collect earliest | |
1041 | basic block on stack that is reachable via backward edge. Articulation | |
1042 | is any basic block such that there is no backward edge bypassing it. | |
1043 | To reduce stack usage we maintain heap allocated stack in STACK vector. | |
1044 | AUX pointer of BB is set to index it appears in the stack or -1 once | |
1045 | it is visited and popped off the stack. | |
1046 | ||
1047 | The algorithm finds articulation after visiting the whole component | |
1048 | reachable by it. This makes it convenient to collect information about | |
1049 | the component used by consider_split. */ | |
1050 | ||
1051 | static void | |
1052 | find_split_points (int overall_time, int overall_size) | |
1053 | { | |
1054 | stack_entry first; | |
1e094109 | 1055 | vec<stack_entry> stack = vNULL; |
2862cf88 | 1056 | basic_block bb; |
1057 | basic_block return_bb = find_return_bb (); | |
1058 | struct split_point current; | |
1059 | ||
1060 | current.header_time = overall_time; | |
1061 | current.header_size = overall_size; | |
1062 | current.split_time = 0; | |
1063 | current.split_size = 0; | |
1064 | current.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
1065 | ||
34154e27 | 1066 | first.bb = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
2862cf88 | 1067 | first.edge_num = 0; |
1068 | first.overall_time = 0; | |
1069 | first.overall_size = 0; | |
1070 | first.earliest = INT_MAX; | |
1071 | first.set_ssa_names = 0; | |
1072 | first.used_ssa_names = 0; | |
60141df0 | 1073 | first.non_ssa_vars = 0; |
2862cf88 | 1074 | first.bbs_visited = 0; |
60141df0 | 1075 | first.can_split = false; |
f1f41a6c | 1076 | stack.safe_push (first); |
34154e27 | 1077 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux = (void *)(intptr_t)-1; |
2862cf88 | 1078 | |
f1f41a6c | 1079 | while (!stack.is_empty ()) |
2862cf88 | 1080 | { |
f1f41a6c | 1081 | stack_entry *entry = &stack.last (); |
2862cf88 | 1082 | |
1083 | /* We are walking an acyclic graph, so edge_num counts | |
1084 | succ and pred edges together. However when considering | |
1085 | articulation, we want to have processed everything reachable | |
1086 | from articulation but nothing that reaches into it. */ | |
1087 | if (entry->edge_num == EDGE_COUNT (entry->bb->succs) | |
34154e27 | 1088 | && entry->bb != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
2862cf88 | 1089 | { |
f1f41a6c | 1090 | int pos = stack.length (); |
2862cf88 | 1091 | entry->can_split &= visit_bb (entry->bb, return_bb, |
1092 | entry->set_ssa_names, | |
1093 | entry->used_ssa_names, | |
1094 | entry->non_ssa_vars); | |
1095 | if (pos <= entry->earliest && !entry->can_split | |
1096 | && dump_file && (dump_flags & TDF_DETAILS)) | |
1097 | fprintf (dump_file, | |
1098 | "found articulation at bb %i but can not split\n", | |
1099 | entry->bb->index); | |
1100 | if (pos <= entry->earliest && entry->can_split) | |
1101 | { | |
1102 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1103 | fprintf (dump_file, "found articulation at bb %i\n", | |
1104 | entry->bb->index); | |
1105 | current.entry_bb = entry->bb; | |
1106 | current.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
1107 | bitmap_and_compl (current.ssa_names_to_pass, | |
1108 | entry->used_ssa_names, entry->set_ssa_names); | |
1109 | current.header_time = overall_time - entry->overall_time; | |
1110 | current.header_size = overall_size - entry->overall_size; | |
1111 | current.split_time = entry->overall_time; | |
1112 | current.split_size = entry->overall_size; | |
1113 | current.split_bbs = entry->bbs_visited; | |
1114 | consider_split (¤t, entry->non_ssa_vars, return_bb); | |
1115 | BITMAP_FREE (current.ssa_names_to_pass); | |
1116 | } | |
1117 | } | |
1118 | /* Do actual DFS walk. */ | |
1119 | if (entry->edge_num | |
1120 | < (EDGE_COUNT (entry->bb->succs) | |
1121 | + EDGE_COUNT (entry->bb->preds))) | |
1122 | { | |
1123 | edge e; | |
1124 | basic_block dest; | |
1125 | if (entry->edge_num < EDGE_COUNT (entry->bb->succs)) | |
1126 | { | |
1127 | e = EDGE_SUCC (entry->bb, entry->edge_num); | |
1128 | dest = e->dest; | |
1129 | } | |
1130 | else | |
1131 | { | |
1132 | e = EDGE_PRED (entry->bb, entry->edge_num | |
1133 | - EDGE_COUNT (entry->bb->succs)); | |
1134 | dest = e->src; | |
1135 | } | |
1136 | ||
1137 | entry->edge_num++; | |
1138 | ||
1139 | /* New BB to visit, push it to the stack. */ | |
34154e27 | 1140 | if (dest != return_bb && dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
2862cf88 | 1141 | && !dest->aux) |
1142 | { | |
1143 | stack_entry new_entry; | |
1144 | ||
1145 | new_entry.bb = dest; | |
1146 | new_entry.edge_num = 0; | |
1147 | new_entry.overall_time | |
f1f41a6c | 1148 | = bb_info_vec[dest->index].time; |
2862cf88 | 1149 | new_entry.overall_size |
f1f41a6c | 1150 | = bb_info_vec[dest->index].size; |
2862cf88 | 1151 | new_entry.earliest = INT_MAX; |
1152 | new_entry.set_ssa_names = BITMAP_ALLOC (NULL); | |
1153 | new_entry.used_ssa_names = BITMAP_ALLOC (NULL); | |
1154 | new_entry.bbs_visited = BITMAP_ALLOC (NULL); | |
1155 | new_entry.non_ssa_vars = BITMAP_ALLOC (NULL); | |
1156 | new_entry.can_split = true; | |
1157 | bitmap_set_bit (new_entry.bbs_visited, dest->index); | |
f1f41a6c | 1158 | stack.safe_push (new_entry); |
1159 | dest->aux = (void *)(intptr_t)stack.length (); | |
2862cf88 | 1160 | } |
1161 | /* Back edge found, record the earliest point. */ | |
1162 | else if ((intptr_t)dest->aux > 0 | |
1163 | && (intptr_t)dest->aux < entry->earliest) | |
1164 | entry->earliest = (intptr_t)dest->aux; | |
1165 | } | |
574c4ab5 | 1166 | /* We are done with examining the edges. Pop off the value from stack |
1167 | and merge stuff we accumulate during the walk. */ | |
34154e27 | 1168 | else if (entry->bb != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
2862cf88 | 1169 | { |
f1f41a6c | 1170 | stack_entry *prev = &stack[stack.length () - 2]; |
2862cf88 | 1171 | |
1172 | entry->bb->aux = (void *)(intptr_t)-1; | |
1173 | prev->can_split &= entry->can_split; | |
1174 | if (prev->set_ssa_names) | |
1175 | { | |
1176 | bitmap_ior_into (prev->set_ssa_names, entry->set_ssa_names); | |
1177 | bitmap_ior_into (prev->used_ssa_names, entry->used_ssa_names); | |
1178 | bitmap_ior_into (prev->bbs_visited, entry->bbs_visited); | |
1179 | bitmap_ior_into (prev->non_ssa_vars, entry->non_ssa_vars); | |
1180 | } | |
1181 | if (prev->earliest > entry->earliest) | |
1182 | prev->earliest = entry->earliest; | |
1183 | prev->overall_time += entry->overall_time; | |
1184 | prev->overall_size += entry->overall_size; | |
1185 | BITMAP_FREE (entry->set_ssa_names); | |
1186 | BITMAP_FREE (entry->used_ssa_names); | |
1187 | BITMAP_FREE (entry->bbs_visited); | |
1188 | BITMAP_FREE (entry->non_ssa_vars); | |
f1f41a6c | 1189 | stack.pop (); |
2862cf88 | 1190 | } |
1191 | else | |
f1f41a6c | 1192 | stack.pop (); |
2862cf88 | 1193 | } |
34154e27 | 1194 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux = NULL; |
fc00614f | 1195 | FOR_EACH_BB_FN (bb, cfun) |
2862cf88 | 1196 | bb->aux = NULL; |
f1f41a6c | 1197 | stack.release (); |
2862cf88 | 1198 | BITMAP_FREE (current.ssa_names_to_pass); |
1199 | } | |
1200 | ||
058a1b7a | 1201 | /* Build and insert initialization of returned bounds RETBND |
1202 | for returned value RETVAL. Statements are inserted after | |
1203 | a statement pointed by GSI and GSI is modified to point to | |
1204 | the last inserted statement. */ | |
1205 | ||
1206 | static void | |
1207 | insert_bndret_call_after (tree retbnd, tree retval, gimple_stmt_iterator *gsi) | |
1208 | { | |
1209 | tree fndecl = targetm.builtin_chkp_function (BUILT_IN_CHKP_BNDRET); | |
1210 | gimple bndret = gimple_build_call (fndecl, 1, retval); | |
1211 | gimple_call_set_lhs (bndret, retbnd); | |
1212 | gsi_insert_after (gsi, bndret, GSI_CONTINUE_LINKING); | |
1213 | } | |
2862cf88 | 1214 | /* Split function at SPLIT_POINT. */ |
1215 | ||
1216 | static void | |
1217 | split_function (struct split_point *split_point) | |
1218 | { | |
1e094109 | 1219 | vec<tree> args_to_pass = vNULL; |
982ffd8d | 1220 | bitmap args_to_skip; |
2862cf88 | 1221 | tree parm; |
1222 | int num = 0; | |
415d1b9a | 1223 | cgraph_node *node, *cur_node = cgraph_node::get (current_function_decl); |
2862cf88 | 1224 | basic_block return_bb = find_return_bb (); |
1225 | basic_block call_bb; | |
1a91d914 | 1226 | gcall *call; |
2862cf88 | 1227 | edge e; |
1228 | edge_iterator ei; | |
058a1b7a | 1229 | tree retval = NULL, real_retval = NULL, retbnd = NULL; |
2862cf88 | 1230 | bool split_part_return_p = false; |
058a1b7a | 1231 | bool with_bounds = chkp_function_instrumented_p (current_function_decl); |
2862cf88 | 1232 | gimple last_stmt = NULL; |
e65564ab | 1233 | unsigned int i; |
c6dfe037 | 1234 | tree arg, ddef; |
f1f41a6c | 1235 | vec<tree, va_gc> **debug_args = NULL; |
2862cf88 | 1236 | |
1237 | if (dump_file) | |
1238 | { | |
1239 | fprintf (dump_file, "\n\nSplitting function at:\n"); | |
1240 | dump_split_point (dump_file, split_point); | |
1241 | } | |
1242 | ||
982ffd8d | 1243 | if (cur_node->local.can_change_signature) |
1244 | args_to_skip = BITMAP_ALLOC (NULL); | |
1245 | else | |
1246 | args_to_skip = NULL; | |
1247 | ||
2862cf88 | 1248 | /* Collect the parameters of new function and args_to_skip bitmap. */ |
1249 | for (parm = DECL_ARGUMENTS (current_function_decl); | |
1767a056 | 1250 | parm; parm = DECL_CHAIN (parm), num++) |
982ffd8d | 1251 | if (args_to_skip |
1252 | && (!is_gimple_reg (parm) | |
c6dfe037 | 1253 | || (ddef = ssa_default_def (cfun, parm)) == NULL_TREE |
982ffd8d | 1254 | || !bitmap_bit_p (split_point->ssa_names_to_pass, |
c6dfe037 | 1255 | SSA_NAME_VERSION (ddef)))) |
2862cf88 | 1256 | bitmap_set_bit (args_to_skip, num); |
1257 | else | |
e65564ab | 1258 | { |
17c5f86d | 1259 | /* This parm might not have been used up to now, but is going to be |
1260 | used, hence register it. */ | |
17c5f86d | 1261 | if (is_gimple_reg (parm)) |
c6dfe037 | 1262 | arg = get_or_create_ssa_default_def (cfun, parm); |
17c5f86d | 1263 | else |
1264 | arg = parm; | |
982ffd8d | 1265 | |
0ed25048 | 1266 | if (!useless_type_conversion_p (DECL_ARG_TYPE (parm), TREE_TYPE (arg))) |
1267 | arg = fold_convert (DECL_ARG_TYPE (parm), arg); | |
f1f41a6c | 1268 | args_to_pass.safe_push (arg); |
e65564ab | 1269 | } |
2862cf88 | 1270 | |
1271 | /* See if the split function will return. */ | |
1272 | FOR_EACH_EDGE (e, ei, return_bb->preds) | |
1273 | if (bitmap_bit_p (split_point->split_bbs, e->src->index)) | |
1274 | break; | |
1275 | if (e) | |
1276 | split_part_return_p = true; | |
1277 | ||
b04bab7c | 1278 | /* Add return block to what will become the split function. |
1279 | We do not return; no return block is needed. */ | |
1280 | if (!split_part_return_p) | |
1281 | ; | |
1282 | /* We have no return block, so nothing is needed. */ | |
34154e27 | 1283 | else if (return_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
b04bab7c | 1284 | ; |
1285 | /* When we do not want to return value, we need to construct | |
1286 | new return block with empty return statement. | |
1287 | FIXME: Once we are able to change return type, we should change function | |
1288 | to return void instead of just outputting function with undefined return | |
1289 | value. For structures this affects quality of codegen. */ | |
1290 | else if (!split_point->split_part_set_retval | |
1291 | && find_retval (return_bb)) | |
1292 | { | |
1293 | bool redirected = true; | |
1294 | basic_block new_return_bb = create_basic_block (NULL, 0, return_bb); | |
1295 | gimple_stmt_iterator gsi = gsi_start_bb (new_return_bb); | |
1296 | gsi_insert_after (&gsi, gimple_build_return (NULL), GSI_NEW_STMT); | |
1297 | while (redirected) | |
1298 | { | |
1299 | redirected = false; | |
1300 | FOR_EACH_EDGE (e, ei, return_bb->preds) | |
1301 | if (bitmap_bit_p (split_point->split_bbs, e->src->index)) | |
1302 | { | |
1303 | new_return_bb->count += e->count; | |
1304 | new_return_bb->frequency += EDGE_FREQUENCY (e); | |
1305 | redirect_edge_and_branch (e, new_return_bb); | |
1306 | redirected = true; | |
1307 | break; | |
1308 | } | |
1309 | } | |
34154e27 | 1310 | e = make_edge (new_return_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0); |
b04bab7c | 1311 | e->probability = REG_BR_PROB_BASE; |
1312 | e->count = new_return_bb->count; | |
b3083327 | 1313 | add_bb_to_loop (new_return_bb, current_loops->tree_root); |
b04bab7c | 1314 | bitmap_set_bit (split_point->split_bbs, new_return_bb->index); |
c13d6d8f | 1315 | } |
1316 | /* When we pass around the value, use existing return block. */ | |
1317 | else | |
1318 | bitmap_set_bit (split_point->split_bbs, return_bb->index); | |
1319 | ||
1320 | /* If RETURN_BB has virtual operand PHIs, they must be removed and the | |
1321 | virtual operand marked for renaming as we change the CFG in a way that | |
1d0b727d | 1322 | tree-inline is not able to compensate for. |
c13d6d8f | 1323 | |
1324 | Note this can happen whether or not we have a return value. If we have | |
1325 | a return value, then RETURN_BB may have PHIs for real operands too. */ | |
34154e27 | 1326 | if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
c13d6d8f | 1327 | { |
1d0b727d | 1328 | bool phi_p = false; |
1a91d914 | 1329 | for (gphi_iterator gsi = gsi_start_phis (return_bb); |
1330 | !gsi_end_p (gsi);) | |
b04bab7c | 1331 | { |
1a91d914 | 1332 | gphi *stmt = gsi.phi (); |
7c782c9b | 1333 | if (!virtual_operand_p (gimple_phi_result (stmt))) |
c13d6d8f | 1334 | { |
1335 | gsi_next (&gsi); | |
1336 | continue; | |
1337 | } | |
904ad591 | 1338 | mark_virtual_phi_result_for_renaming (stmt); |
1339 | remove_phi_node (&gsi, true); | |
1d0b727d | 1340 | phi_p = true; |
b04bab7c | 1341 | } |
1d0b727d | 1342 | /* In reality we have to rename the reaching definition of the |
1343 | virtual operand at return_bb as we will eventually release it | |
1344 | when we remove the code region we outlined. | |
1345 | So we have to rename all immediate virtual uses of that region | |
1346 | if we didn't see a PHI definition yet. */ | |
1347 | /* ??? In real reality we want to set the reaching vdef of the | |
1348 | entry of the SESE region as the vuse of the call and the reaching | |
1349 | vdef of the exit of the SESE region as the vdef of the call. */ | |
1350 | if (!phi_p) | |
1a91d914 | 1351 | for (gimple_stmt_iterator gsi = gsi_start_bb (return_bb); |
1352 | !gsi_end_p (gsi); | |
1353 | gsi_next (&gsi)) | |
1d0b727d | 1354 | { |
1355 | gimple stmt = gsi_stmt (gsi); | |
1356 | if (gimple_vuse (stmt)) | |
1357 | { | |
1358 | gimple_set_vuse (stmt, NULL_TREE); | |
1359 | update_stmt (stmt); | |
1360 | } | |
1361 | if (gimple_vdef (stmt)) | |
1362 | break; | |
1363 | } | |
b04bab7c | 1364 | } |
2862cf88 | 1365 | |
1366 | /* Now create the actual clone. */ | |
35ee1c66 | 1367 | cgraph_edge::rebuild_edges (); |
415d1b9a | 1368 | node = cur_node->create_version_clone_with_body |
1369 | (vNULL, NULL, args_to_skip, !split_part_return_p, split_point->split_bbs, | |
1370 | split_point->entry_bb, "part"); | |
af48f0b1 | 1371 | |
1372 | /* Let's take a time profile for splitted function. */ | |
1373 | node->tp_first_run = cur_node->tp_first_run + 1; | |
1374 | ||
fd8d648f | 1375 | /* For usual cloning it is enough to clear builtin only when signature |
1376 | changes. For partial inlining we however can not expect the part | |
1377 | of builtin implementation to have same semantic as the whole. */ | |
02774f2d | 1378 | if (DECL_BUILT_IN (node->decl)) |
fd8d648f | 1379 | { |
02774f2d | 1380 | DECL_BUILT_IN_CLASS (node->decl) = NOT_BUILT_IN; |
1381 | DECL_FUNCTION_CODE (node->decl) = (enum built_in_function) 0; | |
fd8d648f | 1382 | } |
058a1b7a | 1383 | |
1384 | /* If the original function is instrumented then it's | |
1385 | part is also instrumented. */ | |
1386 | if (with_bounds) | |
1387 | chkp_function_mark_instrumented (node->decl); | |
1388 | ||
ea03e543 | 1389 | /* If the original function is declared inline, there is no point in issuing |
1390 | a warning for the non-inlinable part. */ | |
02774f2d | 1391 | DECL_NO_INLINE_WARNING_P (node->decl) = 1; |
415d1b9a | 1392 | cur_node->remove_callees (); |
51ce5652 | 1393 | cur_node->remove_all_references (); |
2862cf88 | 1394 | if (!split_part_return_p) |
02774f2d | 1395 | TREE_THIS_VOLATILE (node->decl) = 1; |
2862cf88 | 1396 | if (dump_file) |
02774f2d | 1397 | dump_function_to_file (node->decl, dump_file, dump_flags); |
2862cf88 | 1398 | |
1399 | /* Create the basic block we place call into. It is the entry basic block | |
1400 | split after last label. */ | |
1401 | call_bb = split_point->entry_bb; | |
1a91d914 | 1402 | for (gimple_stmt_iterator gsi = gsi_start_bb (call_bb); !gsi_end_p (gsi);) |
2862cf88 | 1403 | if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL) |
1404 | { | |
1405 | last_stmt = gsi_stmt (gsi); | |
1406 | gsi_next (&gsi); | |
1407 | } | |
1408 | else | |
1409 | break; | |
1410 | e = split_block (split_point->entry_bb, last_stmt); | |
1411 | remove_edge (e); | |
1412 | ||
1413 | /* Produce the call statement. */ | |
1a91d914 | 1414 | gimple_stmt_iterator gsi = gsi_last_bb (call_bb); |
f1f41a6c | 1415 | FOR_EACH_VEC_ELT (args_to_pass, i, arg) |
0ed25048 | 1416 | if (!is_gimple_val (arg)) |
1417 | { | |
1418 | arg = force_gimple_operand_gsi (&gsi, arg, true, NULL_TREE, | |
ad676199 | 1419 | false, GSI_CONTINUE_LINKING); |
f1f41a6c | 1420 | args_to_pass[i] = arg; |
0ed25048 | 1421 | } |
02774f2d | 1422 | call = gimple_build_call_vec (node->decl, args_to_pass); |
058a1b7a | 1423 | gimple_call_set_with_bounds (call, with_bounds); |
2862cf88 | 1424 | gimple_set_block (call, DECL_INITIAL (current_function_decl)); |
f1f41a6c | 1425 | args_to_pass.release (); |
2862cf88 | 1426 | |
eee0ea7c | 1427 | /* For optimized away parameters, add on the caller side |
1428 | before the call | |
1429 | DEBUG D#X => parm_Y(D) | |
1430 | stmts and associate D#X with parm in decl_debug_args_lookup | |
1431 | vector to say for debug info that if parameter parm had been passed, | |
1432 | it would have value parm_Y(D). */ | |
1433 | if (args_to_skip) | |
1434 | for (parm = DECL_ARGUMENTS (current_function_decl), num = 0; | |
1435 | parm; parm = DECL_CHAIN (parm), num++) | |
1436 | if (bitmap_bit_p (args_to_skip, num) | |
1437 | && is_gimple_reg (parm)) | |
1438 | { | |
1439 | tree ddecl; | |
1440 | gimple def_temp; | |
1441 | ||
1442 | /* This needs to be done even without MAY_HAVE_DEBUG_STMTS, | |
1443 | otherwise if it didn't exist before, we'd end up with | |
1444 | different SSA_NAME_VERSIONs between -g and -g0. */ | |
1445 | arg = get_or_create_ssa_default_def (cfun, parm); | |
1446 | if (!MAY_HAVE_DEBUG_STMTS) | |
1447 | continue; | |
1448 | ||
1449 | if (debug_args == NULL) | |
02774f2d | 1450 | debug_args = decl_debug_args_insert (node->decl); |
eee0ea7c | 1451 | ddecl = make_node (DEBUG_EXPR_DECL); |
1452 | DECL_ARTIFICIAL (ddecl) = 1; | |
1453 | TREE_TYPE (ddecl) = TREE_TYPE (parm); | |
1454 | DECL_MODE (ddecl) = DECL_MODE (parm); | |
f1f41a6c | 1455 | vec_safe_push (*debug_args, DECL_ORIGIN (parm)); |
1456 | vec_safe_push (*debug_args, ddecl); | |
eee0ea7c | 1457 | def_temp = gimple_build_debug_bind (ddecl, unshare_expr (arg), |
1458 | call); | |
1459 | gsi_insert_after (&gsi, def_temp, GSI_NEW_STMT); | |
1460 | } | |
1461 | /* And on the callee side, add | |
1462 | DEBUG D#Y s=> parm | |
1463 | DEBUG var => D#Y | |
1464 | stmts to the first bb where var is a VAR_DECL created for the | |
1465 | optimized away parameter in DECL_INITIAL block. This hints | |
1466 | in the debug info that var (whole DECL_ORIGIN is the parm PARM_DECL) | |
1467 | is optimized away, but could be looked up at the call site | |
1468 | as value of D#X there. */ | |
1469 | if (debug_args != NULL) | |
1470 | { | |
1471 | unsigned int i; | |
1472 | tree var, vexpr; | |
1473 | gimple_stmt_iterator cgsi; | |
1474 | gimple def_temp; | |
1475 | ||
02774f2d | 1476 | push_cfun (DECL_STRUCT_FUNCTION (node->decl)); |
1477 | var = BLOCK_VARS (DECL_INITIAL (node->decl)); | |
f1f41a6c | 1478 | i = vec_safe_length (*debug_args); |
34154e27 | 1479 | cgsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun))); |
eee0ea7c | 1480 | do |
1481 | { | |
1482 | i -= 2; | |
1483 | while (var != NULL_TREE | |
f1f41a6c | 1484 | && DECL_ABSTRACT_ORIGIN (var) != (**debug_args)[i]) |
eee0ea7c | 1485 | var = TREE_CHAIN (var); |
1486 | if (var == NULL_TREE) | |
1487 | break; | |
1488 | vexpr = make_node (DEBUG_EXPR_DECL); | |
f1f41a6c | 1489 | parm = (**debug_args)[i]; |
eee0ea7c | 1490 | DECL_ARTIFICIAL (vexpr) = 1; |
1491 | TREE_TYPE (vexpr) = TREE_TYPE (parm); | |
1492 | DECL_MODE (vexpr) = DECL_MODE (parm); | |
1493 | def_temp = gimple_build_debug_source_bind (vexpr, parm, | |
1494 | NULL); | |
1495 | gsi_insert_before (&cgsi, def_temp, GSI_SAME_STMT); | |
1496 | def_temp = gimple_build_debug_bind (var, vexpr, NULL); | |
1497 | gsi_insert_before (&cgsi, def_temp, GSI_SAME_STMT); | |
1498 | } | |
1499 | while (i); | |
1500 | pop_cfun (); | |
1501 | } | |
1502 | ||
a8005893 | 1503 | /* We avoid address being taken on any variable used by split part, |
1504 | so return slot optimization is always possible. Moreover this is | |
1505 | required to make DECL_BY_REFERENCE work. */ | |
1506 | if (aggregate_value_p (DECL_RESULT (current_function_decl), | |
8ad1eb69 | 1507 | TREE_TYPE (current_function_decl)) |
1508 | && (!is_gimple_reg_type (TREE_TYPE (DECL_RESULT (current_function_decl))) | |
1509 | || DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))) | |
a8005893 | 1510 | gimple_call_set_return_slot_opt (call, true); |
1511 | ||
2862cf88 | 1512 | /* Update return value. This is bit tricky. When we do not return, |
1513 | do nothing. When we return we might need to update return_bb | |
1514 | or produce a new return statement. */ | |
1515 | if (!split_part_return_p) | |
1516 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1517 | else | |
1518 | { | |
1519 | e = make_edge (call_bb, return_bb, | |
34154e27 | 1520 | return_bb == EXIT_BLOCK_PTR_FOR_FN (cfun) |
1521 | ? 0 : EDGE_FALLTHRU); | |
2862cf88 | 1522 | e->count = call_bb->count; |
1523 | e->probability = REG_BR_PROB_BASE; | |
524a0531 | 1524 | |
1525 | /* If there is return basic block, see what value we need to store | |
1526 | return value into and put call just before it. */ | |
34154e27 | 1527 | if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
2862cf88 | 1528 | { |
4493dab3 | 1529 | real_retval = retval = find_retval (return_bb); |
058a1b7a | 1530 | retbnd = find_retbnd (return_bb); |
524a0531 | 1531 | |
b04bab7c | 1532 | if (real_retval && split_point->split_part_set_retval) |
2862cf88 | 1533 | { |
1a91d914 | 1534 | gphi_iterator psi; |
2862cf88 | 1535 | |
524a0531 | 1536 | /* See if we need new SSA_NAME for the result. |
1537 | When DECL_BY_REFERENCE is true, retval is actually pointer to | |
1538 | return value and it is constant in whole function. */ | |
1539 | if (TREE_CODE (retval) == SSA_NAME | |
1540 | && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
2862cf88 | 1541 | { |
874117c8 | 1542 | retval = copy_ssa_name (retval, call); |
524a0531 | 1543 | |
1544 | /* See if there is PHI defining return value. */ | |
1545 | for (psi = gsi_start_phis (return_bb); | |
1546 | !gsi_end_p (psi); gsi_next (&psi)) | |
1a91d914 | 1547 | if (!virtual_operand_p (gimple_phi_result (psi.phi ()))) |
524a0531 | 1548 | break; |
1549 | ||
1550 | /* When there is PHI, just update its value. */ | |
2862cf88 | 1551 | if (TREE_CODE (retval) == SSA_NAME |
1552 | && !gsi_end_p (psi)) | |
1a91d914 | 1553 | add_phi_arg (psi.phi (), retval, e, UNKNOWN_LOCATION); |
524a0531 | 1554 | /* Otherwise update the return BB itself. |
1555 | find_return_bb allows at most one assignment to return value, | |
1556 | so update first statement. */ | |
1557 | else | |
2862cf88 | 1558 | { |
4493dab3 | 1559 | gimple_stmt_iterator bsi; |
1560 | for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); | |
1561 | gsi_next (&bsi)) | |
1a91d914 | 1562 | if (greturn *return_stmt |
1563 | = dyn_cast <greturn *> (gsi_stmt (bsi))) | |
4493dab3 | 1564 | { |
1a91d914 | 1565 | gimple_return_set_retval (return_stmt, retval); |
4493dab3 | 1566 | break; |
1567 | } | |
0f41c0cf | 1568 | else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN |
1569 | && !gimple_clobber_p (gsi_stmt (bsi))) | |
4493dab3 | 1570 | { |
1571 | gimple_assign_set_rhs1 (gsi_stmt (bsi), retval); | |
1572 | break; | |
1573 | } | |
1574 | update_stmt (gsi_stmt (bsi)); | |
2862cf88 | 1575 | } |
058a1b7a | 1576 | |
1577 | /* Replace retbnd with new one. */ | |
1578 | if (retbnd) | |
1579 | { | |
1580 | gimple_stmt_iterator bsi; | |
1581 | for (bsi = gsi_last_bb (return_bb); !gsi_end_p (bsi); | |
1582 | gsi_prev (&bsi)) | |
1583 | if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) | |
1584 | { | |
1585 | retbnd = copy_ssa_name (retbnd, call); | |
1586 | gimple_return_set_retbnd (gsi_stmt (bsi), retbnd); | |
1587 | update_stmt (gsi_stmt (bsi)); | |
1588 | break; | |
1589 | } | |
1590 | } | |
2862cf88 | 1591 | } |
a8005893 | 1592 | if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
9ece8f57 | 1593 | { |
1594 | gimple_call_set_lhs (call, build_simple_mem_ref (retval)); | |
1595 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1596 | } | |
a8005893 | 1597 | else |
9ece8f57 | 1598 | { |
1599 | tree restype; | |
1600 | restype = TREE_TYPE (DECL_RESULT (current_function_decl)); | |
1601 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1602 | if (!useless_type_conversion_p (TREE_TYPE (retval), restype)) | |
1603 | { | |
1604 | gimple cpy; | |
f9e245b2 | 1605 | tree tem = create_tmp_reg (restype); |
9ece8f57 | 1606 | tem = make_ssa_name (tem, call); |
e9cf809e | 1607 | cpy = gimple_build_assign (retval, NOP_EXPR, tem); |
9ece8f57 | 1608 | gsi_insert_after (&gsi, cpy, GSI_NEW_STMT); |
1609 | retval = tem; | |
1610 | } | |
058a1b7a | 1611 | /* Build bndret call to obtain returned bounds. */ |
1612 | if (retbnd) | |
1613 | insert_bndret_call_after (retbnd, retval, &gsi); | |
9ece8f57 | 1614 | gimple_call_set_lhs (call, retval); |
1615 | update_stmt (call); | |
1616 | } | |
2862cf88 | 1617 | } |
9ece8f57 | 1618 | else |
1619 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
2862cf88 | 1620 | } |
524a0531 | 1621 | /* We don't use return block (there is either no return in function or |
1622 | multiple of them). So create new basic block with return statement. | |
1623 | */ | |
2862cf88 | 1624 | else |
1625 | { | |
1a91d914 | 1626 | greturn *ret; |
b04bab7c | 1627 | if (split_point->split_part_set_retval |
1628 | && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))) | |
2862cf88 | 1629 | { |
1b268210 | 1630 | retval = DECL_RESULT (current_function_decl); |
9eb0b8ee | 1631 | |
058a1b7a | 1632 | if (chkp_function_instrumented_p (current_function_decl) |
1633 | && BOUNDED_P (retval)) | |
f9e245b2 | 1634 | retbnd = create_tmp_reg (pointer_bounds_type_node); |
058a1b7a | 1635 | |
9eb0b8ee | 1636 | /* We use temporary register to hold value when aggregate_value_p |
1637 | is false. Similarly for DECL_BY_REFERENCE we must avoid extra | |
1638 | copy. */ | |
1639 | if (!aggregate_value_p (retval, TREE_TYPE (current_function_decl)) | |
1640 | && !DECL_BY_REFERENCE (retval)) | |
f9e245b2 | 1641 | retval = create_tmp_reg (TREE_TYPE (retval)); |
2862cf88 | 1642 | if (is_gimple_reg (retval)) |
524a0531 | 1643 | { |
1644 | /* When returning by reference, there is only one SSA name | |
1645 | assigned to RESULT_DECL (that is pointer to return value). | |
1646 | Look it up or create new one if it is missing. */ | |
1647 | if (DECL_BY_REFERENCE (retval)) | |
c6dfe037 | 1648 | retval = get_or_create_ssa_default_def (cfun, retval); |
524a0531 | 1649 | /* Otherwise produce new SSA name for return value. */ |
1650 | else | |
1651 | retval = make_ssa_name (retval, call); | |
1652 | } | |
a8005893 | 1653 | if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
1654 | gimple_call_set_lhs (call, build_simple_mem_ref (retval)); | |
1655 | else | |
1656 | gimple_call_set_lhs (call, retval); | |
2862cf88 | 1657 | } |
1658 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
058a1b7a | 1659 | /* Build bndret call to obtain returned bounds. */ |
1660 | if (retbnd) | |
1661 | insert_bndret_call_after (retbnd, retval, &gsi); | |
2862cf88 | 1662 | ret = gimple_build_return (retval); |
1663 | gsi_insert_after (&gsi, ret, GSI_NEW_STMT); | |
1664 | } | |
1665 | } | |
1666 | free_dominance_info (CDI_DOMINATORS); | |
1667 | free_dominance_info (CDI_POST_DOMINATORS); | |
a41f2a28 | 1668 | compute_inline_parameters (node, true); |
2862cf88 | 1669 | } |
1670 | ||
1671 | /* Execute function splitting pass. */ | |
1672 | ||
1673 | static unsigned int | |
1674 | execute_split_functions (void) | |
1675 | { | |
1676 | gimple_stmt_iterator bsi; | |
1677 | basic_block bb; | |
1678 | int overall_time = 0, overall_size = 0; | |
1679 | int todo = 0; | |
415d1b9a | 1680 | struct cgraph_node *node = cgraph_node::get (current_function_decl); |
2862cf88 | 1681 | |
f3941af5 | 1682 | if (flags_from_decl_or_type (current_function_decl) |
1683 | & (ECF_NORETURN|ECF_MALLOC)) | |
2862cf88 | 1684 | { |
1685 | if (dump_file) | |
f3941af5 | 1686 | fprintf (dump_file, "Not splitting: noreturn/malloc function.\n"); |
2862cf88 | 1687 | return 0; |
1688 | } | |
1689 | if (MAIN_NAME_P (DECL_NAME (current_function_decl))) | |
1690 | { | |
1691 | if (dump_file) | |
1692 | fprintf (dump_file, "Not splitting: main function.\n"); | |
1693 | return 0; | |
1694 | } | |
1695 | /* This can be relaxed; function might become inlinable after splitting | |
1696 | away the uninlinable part. */ | |
f1f41a6c | 1697 | if (inline_edge_summary_vec.exists () |
b4bae7a0 | 1698 | && !inline_summaries->get (node)->inlinable) |
2862cf88 | 1699 | { |
1700 | if (dump_file) | |
1701 | fprintf (dump_file, "Not splitting: not inlinable.\n"); | |
1702 | return 0; | |
1703 | } | |
02774f2d | 1704 | if (DECL_DISREGARD_INLINE_LIMITS (node->decl)) |
2862cf88 | 1705 | { |
1706 | if (dump_file) | |
574c4ab5 | 1707 | fprintf (dump_file, "Not splitting: disregarding inline limits.\n"); |
2862cf88 | 1708 | return 0; |
1709 | } | |
1710 | /* This can be relaxed; most of versioning tests actually prevents | |
1711 | a duplication. */ | |
1712 | if (!tree_versionable_function_p (current_function_decl)) | |
1713 | { | |
1714 | if (dump_file) | |
1715 | fprintf (dump_file, "Not splitting: not versionable.\n"); | |
1716 | return 0; | |
1717 | } | |
1718 | /* FIXME: we could support this. */ | |
1719 | if (DECL_STRUCT_FUNCTION (current_function_decl)->static_chain_decl) | |
1720 | { | |
1721 | if (dump_file) | |
1722 | fprintf (dump_file, "Not splitting: nested function.\n"); | |
1723 | return 0; | |
1724 | } | |
2862cf88 | 1725 | |
1726 | /* See if it makes sense to try to split. | |
1727 | It makes sense to split if we inline, that is if we have direct calls to | |
1728 | handle or direct calls are possibly going to appear as result of indirect | |
a15d5ede | 1729 | inlining or LTO. Also handle -fprofile-generate as LTO to allow non-LTO |
1730 | training for LTO -fprofile-use build. | |
1731 | ||
2862cf88 | 1732 | Note that we are not completely conservative about disqualifying functions |
1733 | called once. It is possible that the caller is called more then once and | |
1734 | then inlining would still benefit. */ | |
8745ccbf | 1735 | if ((!node->callers |
1736 | /* Local functions called once will be completely inlined most of time. */ | |
1737 | || (!node->callers->next_caller && node->local.local)) | |
02774f2d | 1738 | && !node->address_taken |
1739 | && (!flag_lto || !node->externally_visible)) | |
2862cf88 | 1740 | { |
1741 | if (dump_file) | |
1742 | fprintf (dump_file, "Not splitting: not called directly " | |
1743 | "or called once.\n"); | |
1744 | return 0; | |
1745 | } | |
1746 | ||
1747 | /* FIXME: We can actually split if splitting reduces call overhead. */ | |
1748 | if (!flag_inline_small_functions | |
1749 | && !DECL_DECLARED_INLINE_P (current_function_decl)) | |
1750 | { | |
1751 | if (dump_file) | |
1752 | fprintf (dump_file, "Not splitting: not autoinlining and function" | |
1753 | " is not inline.\n"); | |
1754 | return 0; | |
1755 | } | |
1756 | ||
15ca8f90 | 1757 | /* We enforce splitting after loop headers when profile info is not |
1758 | available. */ | |
f26d8580 | 1759 | if (profile_status_for_fn (cfun) != PROFILE_READ) |
15ca8f90 | 1760 | mark_dfs_back_edges (); |
1761 | ||
aa2edcb9 | 1762 | /* Initialize bitmap to track forbidden calls. */ |
1763 | forbidden_dominators = BITMAP_ALLOC (NULL); | |
1764 | calculate_dominance_info (CDI_DOMINATORS); | |
1765 | ||
2862cf88 | 1766 | /* Compute local info about basic blocks and determine function size/time. */ |
fe672ac0 | 1767 | bb_info_vec.safe_grow_cleared (last_basic_block_for_fn (cfun) + 1); |
2862cf88 | 1768 | memset (&best_split_point, 0, sizeof (best_split_point)); |
fc00614f | 1769 | FOR_EACH_BB_FN (bb, cfun) |
2862cf88 | 1770 | { |
1771 | int time = 0; | |
1772 | int size = 0; | |
1773 | int freq = compute_call_stmt_bb_frequency (current_function_decl, bb); | |
1774 | ||
1775 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1776 | fprintf (dump_file, "Basic block %i\n", bb->index); | |
1777 | ||
1778 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1779 | { | |
1780 | int this_time, this_size; | |
1781 | gimple stmt = gsi_stmt (bsi); | |
1782 | ||
1783 | this_size = estimate_num_insns (stmt, &eni_size_weights); | |
1784 | this_time = estimate_num_insns (stmt, &eni_time_weights) * freq; | |
1785 | size += this_size; | |
1786 | time += this_time; | |
aa2edcb9 | 1787 | check_forbidden_calls (stmt); |
2862cf88 | 1788 | |
1789 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1790 | { | |
1791 | fprintf (dump_file, " freq:%6i size:%3i time:%3i ", | |
1792 | freq, this_size, this_time); | |
1793 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1794 | } | |
1795 | } | |
1796 | overall_time += time; | |
1797 | overall_size += size; | |
f1f41a6c | 1798 | bb_info_vec[bb->index].time = time; |
1799 | bb_info_vec[bb->index].size = size; | |
2862cf88 | 1800 | } |
1801 | find_split_points (overall_time, overall_size); | |
1802 | if (best_split_point.split_bbs) | |
1803 | { | |
1804 | split_function (&best_split_point); | |
1805 | BITMAP_FREE (best_split_point.ssa_names_to_pass); | |
1806 | BITMAP_FREE (best_split_point.split_bbs); | |
1807 | todo = TODO_update_ssa | TODO_cleanup_cfg; | |
1808 | } | |
aa2edcb9 | 1809 | BITMAP_FREE (forbidden_dominators); |
f1f41a6c | 1810 | bb_info_vec.release (); |
2862cf88 | 1811 | return todo; |
1812 | } | |
1813 | ||
cbe8bda8 | 1814 | namespace { |
1815 | ||
1816 | const pass_data pass_data_split_functions = | |
2862cf88 | 1817 | { |
cbe8bda8 | 1818 | GIMPLE_PASS, /* type */ |
1819 | "fnsplit", /* name */ | |
1820 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 1821 | TV_IPA_FNSPLIT, /* tv_id */ |
1822 | PROP_cfg, /* properties_required */ | |
1823 | 0, /* properties_provided */ | |
1824 | 0, /* properties_destroyed */ | |
1825 | 0, /* todo_flags_start */ | |
8b88439e | 1826 | 0, /* todo_flags_finish */ |
2862cf88 | 1827 | }; |
a15d5ede | 1828 | |
cbe8bda8 | 1829 | class pass_split_functions : public gimple_opt_pass |
1830 | { | |
1831 | public: | |
9af5ce0c | 1832 | pass_split_functions (gcc::context *ctxt) |
1833 | : gimple_opt_pass (pass_data_split_functions, ctxt) | |
cbe8bda8 | 1834 | {} |
1835 | ||
1836 | /* opt_pass methods: */ | |
31315c24 | 1837 | virtual bool gate (function *); |
65b0537f | 1838 | virtual unsigned int execute (function *) |
1839 | { | |
1840 | return execute_split_functions (); | |
1841 | } | |
cbe8bda8 | 1842 | |
1843 | }; // class pass_split_functions | |
1844 | ||
31315c24 | 1845 | bool |
1846 | pass_split_functions::gate (function *) | |
1847 | { | |
1848 | /* When doing profile feedback, we want to execute the pass after profiling | |
1849 | is read. So disable one in early optimization. */ | |
1850 | return (flag_partial_inlining | |
1851 | && !profile_arc_flag && !flag_branch_probabilities); | |
1852 | } | |
1853 | ||
cbe8bda8 | 1854 | } // anon namespace |
1855 | ||
1856 | gimple_opt_pass * | |
1857 | make_pass_split_functions (gcc::context *ctxt) | |
1858 | { | |
1859 | return new pass_split_functions (ctxt); | |
1860 | } | |
1861 | ||
a15d5ede | 1862 | /* Execute function splitting pass. */ |
1863 | ||
1864 | static unsigned int | |
1865 | execute_feedback_split_functions (void) | |
1866 | { | |
1867 | unsigned int retval = execute_split_functions (); | |
1868 | if (retval) | |
1869 | retval |= TODO_rebuild_cgraph_edges; | |
1870 | return retval; | |
1871 | } | |
1872 | ||
cbe8bda8 | 1873 | namespace { |
1874 | ||
1875 | const pass_data pass_data_feedback_split_functions = | |
a15d5ede | 1876 | { |
cbe8bda8 | 1877 | GIMPLE_PASS, /* type */ |
1878 | "feedback_fnsplit", /* name */ | |
1879 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 1880 | TV_IPA_FNSPLIT, /* tv_id */ |
1881 | PROP_cfg, /* properties_required */ | |
1882 | 0, /* properties_provided */ | |
1883 | 0, /* properties_destroyed */ | |
1884 | 0, /* todo_flags_start */ | |
8b88439e | 1885 | 0, /* todo_flags_finish */ |
a15d5ede | 1886 | }; |
cbe8bda8 | 1887 | |
1888 | class pass_feedback_split_functions : public gimple_opt_pass | |
1889 | { | |
1890 | public: | |
9af5ce0c | 1891 | pass_feedback_split_functions (gcc::context *ctxt) |
1892 | : gimple_opt_pass (pass_data_feedback_split_functions, ctxt) | |
cbe8bda8 | 1893 | {} |
1894 | ||
1895 | /* opt_pass methods: */ | |
31315c24 | 1896 | virtual bool gate (function *); |
65b0537f | 1897 | virtual unsigned int execute (function *) |
1898 | { | |
1899 | return execute_feedback_split_functions (); | |
1900 | } | |
cbe8bda8 | 1901 | |
1902 | }; // class pass_feedback_split_functions | |
1903 | ||
31315c24 | 1904 | bool |
1905 | pass_feedback_split_functions::gate (function *) | |
1906 | { | |
1907 | /* We don't need to split when profiling at all, we are producing | |
1908 | lousy code anyway. */ | |
1909 | return (flag_partial_inlining | |
1910 | && flag_branch_probabilities); | |
1911 | } | |
1912 | ||
cbe8bda8 | 1913 | } // anon namespace |
1914 | ||
1915 | gimple_opt_pass * | |
1916 | make_pass_feedback_split_functions (gcc::context *ctxt) | |
1917 | { | |
1918 | return new pass_feedback_split_functions (ctxt); | |
1919 | } |