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3e485f62 | 1 | /* Function splitting pass |
a348dc7f | 2 | Copyright (C) 2010, 2011, 2012 |
3e485f62 JH |
3 | Free Software Foundation, Inc. |
4 | Contributed by Jan Hubicka <jh@suse.cz> | |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
10 | Software Foundation; either version 3, or (at your option) any later | |
11 | version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING3. If not see | |
20 | <http://www.gnu.org/licenses/>. */ | |
21 | ||
22 | /* The purpose of this pass is to split function bodies to improve | |
23 | inlining. I.e. for function of the form: | |
24 | ||
25 | func (...) | |
26 | { | |
27 | if (cheap_test) | |
28 | something_small | |
29 | else | |
30 | something_big | |
31 | } | |
32 | ||
33 | Produce: | |
34 | ||
35 | func.part (...) | |
36 | { | |
37 | something_big | |
38 | } | |
39 | ||
40 | func (...) | |
41 | { | |
42 | if (cheap_test) | |
43 | something_small | |
44 | else | |
45 | func.part (...); | |
46 | } | |
47 | ||
48 | When func becomes inlinable and when cheap_test is often true, inlining func, | |
ed7656f6 | 49 | but not fund.part leads to performance improvement similar as inlining |
3e485f62 JH |
50 | original func while the code size growth is smaller. |
51 | ||
52 | The pass is organized in three stages: | |
53 | 1) Collect local info about basic block into BB_INFO structure and | |
54 | compute function body estimated size and time. | |
55 | 2) Via DFS walk find all possible basic blocks where we can split | |
56 | and chose best one. | |
57 | 3) If split point is found, split at the specified BB by creating a clone | |
58 | and updating function to call it. | |
59 | ||
60 | The decisions what functions to split are in execute_split_functions | |
61 | and consider_split. | |
62 | ||
63 | There are several possible future improvements for this pass including: | |
64 | ||
65 | 1) Splitting to break up large functions | |
66 | 2) Splitting to reduce stack frame usage | |
67 | 3) Allow split part of function to use values computed in the header part. | |
68 | The values needs to be passed to split function, perhaps via same | |
69 | interface as for nested functions or as argument. | |
70 | 4) Support for simple rematerialization. I.e. when split part use | |
71 | value computed in header from function parameter in very cheap way, we | |
72 | can just recompute it. | |
73 | 5) Support splitting of nested functions. | |
74 | 6) Support non-SSA arguments. | |
75 | 7) There is nothing preventing us from producing multiple parts of single function | |
76 | when needed or splitting also the parts. */ | |
77 | ||
78 | #include "config.h" | |
79 | #include "system.h" | |
80 | #include "coretypes.h" | |
81 | #include "tree.h" | |
82 | #include "target.h" | |
83 | #include "cgraph.h" | |
84 | #include "ipa-prop.h" | |
85 | #include "tree-flow.h" | |
86 | #include "tree-pass.h" | |
87 | #include "flags.h" | |
88 | #include "timevar.h" | |
89 | #include "diagnostic.h" | |
90 | #include "tree-dump.h" | |
91 | #include "tree-inline.h" | |
92 | #include "fibheap.h" | |
93 | #include "params.h" | |
94 | #include "gimple-pretty-print.h" | |
e7f23018 | 95 | #include "ipa-inline.h" |
3e485f62 JH |
96 | |
97 | /* Per basic block info. */ | |
98 | ||
99 | typedef struct | |
100 | { | |
101 | unsigned int size; | |
102 | unsigned int time; | |
103 | } bb_info; | |
104 | DEF_VEC_O(bb_info); | |
105 | DEF_VEC_ALLOC_O(bb_info,heap); | |
106 | ||
107 | static VEC(bb_info, heap) *bb_info_vec; | |
108 | ||
109 | /* Description of split point. */ | |
110 | ||
111 | struct split_point | |
112 | { | |
113 | /* Size of the partitions. */ | |
114 | unsigned int header_time, header_size, split_time, split_size; | |
115 | ||
ed7656f6 | 116 | /* SSA names that need to be passed into spit function. */ |
3e485f62 JH |
117 | bitmap ssa_names_to_pass; |
118 | ||
119 | /* Basic block where we split (that will become entry point of new function. */ | |
120 | basic_block entry_bb; | |
121 | ||
122 | /* Basic blocks we are splitting away. */ | |
123 | bitmap split_bbs; | |
241a2b9e JH |
124 | |
125 | /* True when return value is computed on split part and thus it needs | |
126 | to be returned. */ | |
127 | bool split_part_set_retval; | |
3e485f62 JH |
128 | }; |
129 | ||
130 | /* Best split point found. */ | |
131 | ||
132 | struct split_point best_split_point; | |
133 | ||
b2e25729 BS |
134 | /* Set of basic blocks that are not allowed to dominate a split point. */ |
135 | ||
136 | static bitmap forbidden_dominators; | |
137 | ||
241a2b9e JH |
138 | static tree find_retval (basic_block return_bb); |
139 | ||
1802378d | 140 | /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
3e485f62 JH |
141 | variable, check it if it is present in bitmap passed via DATA. */ |
142 | ||
143 | static bool | |
1802378d | 144 | test_nonssa_use (gimple stmt ATTRIBUTE_UNUSED, tree t, void *data) |
3e485f62 JH |
145 | { |
146 | t = get_base_address (t); | |
147 | ||
1802378d EB |
148 | if (!t || is_gimple_reg (t)) |
149 | return false; | |
150 | ||
151 | if (TREE_CODE (t) == PARM_DECL | |
152 | || (TREE_CODE (t) == VAR_DECL | |
3e485f62 | 153 | && auto_var_in_fn_p (t, current_function_decl)) |
1802378d EB |
154 | || TREE_CODE (t) == RESULT_DECL |
155 | || TREE_CODE (t) == LABEL_DECL) | |
3e485f62 | 156 | return bitmap_bit_p ((bitmap)data, DECL_UID (t)); |
241a2b9e | 157 | |
1802378d EB |
158 | /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
159 | to pretend that the value pointed to is actual result decl. */ | |
160 | if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) | |
241a2b9e JH |
161 | && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
162 | && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL | |
163 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
1802378d EB |
164 | return |
165 | bitmap_bit_p ((bitmap)data, | |
166 | DECL_UID (DECL_RESULT (current_function_decl))); | |
167 | ||
3e485f62 JH |
168 | return false; |
169 | } | |
170 | ||
171 | /* Dump split point CURRENT. */ | |
172 | ||
173 | static void | |
174 | dump_split_point (FILE * file, struct split_point *current) | |
175 | { | |
176 | fprintf (file, | |
cfef45c8 RG |
177 | "Split point at BB %i\n" |
178 | " header time: %i header size: %i\n" | |
179 | " split time: %i split size: %i\n bbs: ", | |
3e485f62 JH |
180 | current->entry_bb->index, current->header_time, |
181 | current->header_size, current->split_time, current->split_size); | |
182 | dump_bitmap (file, current->split_bbs); | |
183 | fprintf (file, " SSA names to pass: "); | |
184 | dump_bitmap (file, current->ssa_names_to_pass); | |
185 | } | |
186 | ||
1802378d EB |
187 | /* Look for all BBs in header that might lead to the split part and verify |
188 | that they are not defining any non-SSA var used by the split part. | |
2094f1fc JH |
189 | Parameters are the same as for consider_split. */ |
190 | ||
191 | static bool | |
192 | verify_non_ssa_vars (struct split_point *current, bitmap non_ssa_vars, | |
193 | basic_block return_bb) | |
194 | { | |
195 | bitmap seen = BITMAP_ALLOC (NULL); | |
196 | VEC (basic_block,heap) *worklist = NULL; | |
197 | edge e; | |
198 | edge_iterator ei; | |
199 | bool ok = true; | |
1802378d | 200 | |
2094f1fc JH |
201 | FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
202 | if (e->src != ENTRY_BLOCK_PTR | |
203 | && !bitmap_bit_p (current->split_bbs, e->src->index)) | |
204 | { | |
205 | VEC_safe_push (basic_block, heap, worklist, e->src); | |
206 | bitmap_set_bit (seen, e->src->index); | |
207 | } | |
1802378d | 208 | |
2094f1fc JH |
209 | while (!VEC_empty (basic_block, worklist)) |
210 | { | |
211 | gimple_stmt_iterator bsi; | |
212 | basic_block bb = VEC_pop (basic_block, worklist); | |
213 | ||
214 | FOR_EACH_EDGE (e, ei, bb->preds) | |
215 | if (e->src != ENTRY_BLOCK_PTR | |
fcaa4ca4 | 216 | && bitmap_set_bit (seen, e->src->index)) |
2094f1fc JH |
217 | { |
218 | gcc_checking_assert (!bitmap_bit_p (current->split_bbs, | |
219 | e->src->index)); | |
220 | VEC_safe_push (basic_block, heap, worklist, e->src); | |
2094f1fc JH |
221 | } |
222 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
223 | { | |
1802378d EB |
224 | gimple stmt = gsi_stmt (bsi); |
225 | if (is_gimple_debug (stmt)) | |
2094f1fc JH |
226 | continue; |
227 | if (walk_stmt_load_store_addr_ops | |
1802378d EB |
228 | (stmt, non_ssa_vars, test_nonssa_use, test_nonssa_use, |
229 | test_nonssa_use)) | |
2094f1fc JH |
230 | { |
231 | ok = false; | |
232 | goto done; | |
233 | } | |
1802378d EB |
234 | if (gimple_code (stmt) == GIMPLE_LABEL |
235 | && test_nonssa_use (stmt, gimple_label_label (stmt), | |
236 | non_ssa_vars)) | |
237 | { | |
238 | ok = false; | |
239 | goto done; | |
240 | } | |
2094f1fc JH |
241 | } |
242 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
243 | { | |
244 | if (walk_stmt_load_store_addr_ops | |
1802378d EB |
245 | (gsi_stmt (bsi), non_ssa_vars, test_nonssa_use, test_nonssa_use, |
246 | test_nonssa_use)) | |
2094f1fc JH |
247 | { |
248 | ok = false; | |
249 | goto done; | |
250 | } | |
251 | } | |
252 | FOR_EACH_EDGE (e, ei, bb->succs) | |
253 | { | |
254 | if (e->dest != return_bb) | |
255 | continue; | |
256 | for (bsi = gsi_start_phis (return_bb); !gsi_end_p (bsi); | |
257 | gsi_next (&bsi)) | |
258 | { | |
259 | gimple stmt = gsi_stmt (bsi); | |
260 | tree op = gimple_phi_arg_def (stmt, e->dest_idx); | |
261 | ||
262 | if (!is_gimple_reg (gimple_phi_result (stmt))) | |
263 | continue; | |
264 | if (TREE_CODE (op) != SSA_NAME | |
265 | && test_nonssa_use (stmt, op, non_ssa_vars)) | |
266 | { | |
267 | ok = false; | |
268 | goto done; | |
269 | } | |
270 | } | |
271 | } | |
272 | } | |
273 | done: | |
274 | BITMAP_FREE (seen); | |
275 | VEC_free (basic_block, heap, worklist); | |
276 | return ok; | |
277 | } | |
278 | ||
b2e25729 BS |
279 | /* If STMT is a call, check the callee against a list of forbidden |
280 | predicate functions. If a match is found, look for uses of the | |
281 | call result in condition statements that compare against zero. | |
282 | For each such use, find the block targeted by the condition | |
283 | statement for the nonzero result, and set the bit for this block | |
284 | in the forbidden dominators bitmap. The purpose of this is to avoid | |
285 | selecting a split point where we are likely to lose the chance | |
286 | to optimize away an unused function call. */ | |
287 | ||
288 | static void | |
289 | check_forbidden_calls (gimple stmt) | |
290 | { | |
291 | imm_use_iterator use_iter; | |
292 | use_operand_p use_p; | |
293 | tree lhs; | |
294 | ||
295 | /* At the moment, __builtin_constant_p is the only forbidden | |
296 | predicate function call (see PR49642). */ | |
297 | if (!gimple_call_builtin_p (stmt, BUILT_IN_CONSTANT_P)) | |
298 | return; | |
299 | ||
300 | lhs = gimple_call_lhs (stmt); | |
301 | ||
302 | if (!lhs || TREE_CODE (lhs) != SSA_NAME) | |
303 | return; | |
304 | ||
305 | FOR_EACH_IMM_USE_FAST (use_p, use_iter, lhs) | |
306 | { | |
307 | tree op1; | |
308 | basic_block use_bb, forbidden_bb; | |
309 | enum tree_code code; | |
310 | edge true_edge, false_edge; | |
311 | gimple use_stmt = USE_STMT (use_p); | |
312 | ||
313 | if (gimple_code (use_stmt) != GIMPLE_COND) | |
314 | continue; | |
315 | ||
316 | /* Assuming canonical form for GIMPLE_COND here, with constant | |
317 | in second position. */ | |
318 | op1 = gimple_cond_rhs (use_stmt); | |
319 | code = gimple_cond_code (use_stmt); | |
320 | use_bb = gimple_bb (use_stmt); | |
321 | ||
322 | extract_true_false_edges_from_block (use_bb, &true_edge, &false_edge); | |
323 | ||
324 | /* We're only interested in comparisons that distinguish | |
325 | unambiguously from zero. */ | |
326 | if (!integer_zerop (op1) || code == LE_EXPR || code == GE_EXPR) | |
327 | continue; | |
328 | ||
329 | if (code == EQ_EXPR) | |
330 | forbidden_bb = false_edge->dest; | |
331 | else | |
332 | forbidden_bb = true_edge->dest; | |
333 | ||
334 | bitmap_set_bit (forbidden_dominators, forbidden_bb->index); | |
335 | } | |
336 | } | |
337 | ||
338 | /* If BB is dominated by any block in the forbidden dominators set, | |
339 | return TRUE; else FALSE. */ | |
340 | ||
341 | static bool | |
342 | dominated_by_forbidden (basic_block bb) | |
343 | { | |
344 | unsigned dom_bb; | |
345 | bitmap_iterator bi; | |
346 | ||
347 | EXECUTE_IF_SET_IN_BITMAP (forbidden_dominators, 1, dom_bb, bi) | |
348 | { | |
349 | if (dominated_by_p (CDI_DOMINATORS, bb, BASIC_BLOCK (dom_bb))) | |
350 | return true; | |
351 | } | |
352 | ||
353 | return false; | |
354 | } | |
355 | ||
3e485f62 JH |
356 | /* We found an split_point CURRENT. NON_SSA_VARS is bitmap of all non ssa |
357 | variables used and RETURN_BB is return basic block. | |
358 | See if we can split function here. */ | |
359 | ||
360 | static void | |
361 | consider_split (struct split_point *current, bitmap non_ssa_vars, | |
362 | basic_block return_bb) | |
363 | { | |
364 | tree parm; | |
365 | unsigned int num_args = 0; | |
366 | unsigned int call_overhead; | |
367 | edge e; | |
368 | edge_iterator ei; | |
8b3057b3 JH |
369 | gimple_stmt_iterator bsi; |
370 | unsigned int i; | |
ed7656f6 | 371 | int incoming_freq = 0; |
241a2b9e | 372 | tree retval; |
8b3057b3 | 373 | |
3e485f62 JH |
374 | if (dump_file && (dump_flags & TDF_DETAILS)) |
375 | dump_split_point (dump_file, current); | |
376 | ||
8b3057b3 JH |
377 | FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
378 | if (!bitmap_bit_p (current->split_bbs, e->src->index)) | |
ed7656f6 | 379 | incoming_freq += EDGE_FREQUENCY (e); |
8b3057b3 | 380 | |
3e485f62 | 381 | /* Do not split when we would end up calling function anyway. */ |
ed7656f6 | 382 | if (incoming_freq |
3e485f62 JH |
383 | >= (ENTRY_BLOCK_PTR->frequency |
384 | * PARAM_VALUE (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY) / 100)) | |
385 | { | |
386 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
387 | fprintf (dump_file, | |
ed7656f6 | 388 | " Refused: incoming frequency is too large.\n"); |
3e485f62 JH |
389 | return; |
390 | } | |
391 | ||
392 | if (!current->header_size) | |
393 | { | |
394 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
395 | fprintf (dump_file, " Refused: header empty\n"); | |
3e485f62 JH |
396 | return; |
397 | } | |
398 | ||
ed7656f6 JJ |
399 | /* Verify that PHI args on entry are either virtual or all their operands |
400 | incoming from header are the same. */ | |
8b3057b3 | 401 | for (bsi = gsi_start_phis (current->entry_bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
3e485f62 | 402 | { |
8b3057b3 JH |
403 | gimple stmt = gsi_stmt (bsi); |
404 | tree val = NULL; | |
405 | ||
406 | if (!is_gimple_reg (gimple_phi_result (stmt))) | |
407 | continue; | |
408 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
409 | { | |
410 | edge e = gimple_phi_arg_edge (stmt, i); | |
411 | if (!bitmap_bit_p (current->split_bbs, e->src->index)) | |
412 | { | |
413 | tree edge_val = gimple_phi_arg_def (stmt, i); | |
414 | if (val && edge_val != val) | |
415 | { | |
416 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
417 | fprintf (dump_file, | |
418 | " Refused: entry BB has PHI with multiple variants\n"); | |
419 | return; | |
420 | } | |
421 | val = edge_val; | |
422 | } | |
423 | } | |
3e485f62 JH |
424 | } |
425 | ||
426 | ||
427 | /* See what argument we will pass to the split function and compute | |
428 | call overhead. */ | |
429 | call_overhead = eni_size_weights.call_cost; | |
430 | for (parm = DECL_ARGUMENTS (current_function_decl); parm; | |
910ad8de | 431 | parm = DECL_CHAIN (parm)) |
3e485f62 JH |
432 | { |
433 | if (!is_gimple_reg (parm)) | |
434 | { | |
435 | if (bitmap_bit_p (non_ssa_vars, DECL_UID (parm))) | |
436 | { | |
437 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
438 | fprintf (dump_file, | |
439 | " Refused: need to pass non-ssa param values\n"); | |
440 | return; | |
441 | } | |
442 | } | |
443 | else if (gimple_default_def (cfun, parm) | |
444 | && bitmap_bit_p (current->ssa_names_to_pass, | |
445 | SSA_NAME_VERSION (gimple_default_def | |
446 | (cfun, parm)))) | |
447 | { | |
448 | if (!VOID_TYPE_P (TREE_TYPE (parm))) | |
449 | call_overhead += estimate_move_cost (TREE_TYPE (parm)); | |
450 | num_args++; | |
451 | } | |
452 | } | |
453 | if (!VOID_TYPE_P (TREE_TYPE (current_function_decl))) | |
454 | call_overhead += estimate_move_cost (TREE_TYPE (current_function_decl)); | |
455 | ||
456 | if (current->split_size <= call_overhead) | |
457 | { | |
458 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
459 | fprintf (dump_file, | |
460 | " Refused: split size is smaller than call overhead\n"); | |
461 | return; | |
462 | } | |
463 | if (current->header_size + call_overhead | |
464 | >= (unsigned int)(DECL_DECLARED_INLINE_P (current_function_decl) | |
465 | ? MAX_INLINE_INSNS_SINGLE | |
466 | : MAX_INLINE_INSNS_AUTO)) | |
467 | { | |
468 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
469 | fprintf (dump_file, | |
470 | " Refused: header size is too large for inline candidate\n"); | |
471 | return; | |
472 | } | |
473 | ||
474 | /* FIXME: we currently can pass only SSA function parameters to the split | |
d402c33d | 475 | arguments. Once parm_adjustment infrastructure is supported by cloning, |
3e485f62 JH |
476 | we can pass more than that. */ |
477 | if (num_args != bitmap_count_bits (current->ssa_names_to_pass)) | |
478 | { | |
8b3057b3 | 479 | |
3e485f62 JH |
480 | if (dump_file && (dump_flags & TDF_DETAILS)) |
481 | fprintf (dump_file, | |
482 | " Refused: need to pass non-param values\n"); | |
483 | return; | |
484 | } | |
485 | ||
486 | /* When there are non-ssa vars used in the split region, see if they | |
487 | are used in the header region. If so, reject the split. | |
488 | FIXME: we can use nested function support to access both. */ | |
2094f1fc JH |
489 | if (!bitmap_empty_p (non_ssa_vars) |
490 | && !verify_non_ssa_vars (current, non_ssa_vars, return_bb)) | |
3e485f62 | 491 | { |
2094f1fc JH |
492 | if (dump_file && (dump_flags & TDF_DETAILS)) |
493 | fprintf (dump_file, | |
494 | " Refused: split part has non-ssa uses\n"); | |
3e485f62 JH |
495 | return; |
496 | } | |
b2e25729 BS |
497 | |
498 | /* If the split point is dominated by a forbidden block, reject | |
499 | the split. */ | |
500 | if (!bitmap_empty_p (forbidden_dominators) | |
501 | && dominated_by_forbidden (current->entry_bb)) | |
502 | { | |
503 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
504 | fprintf (dump_file, | |
505 | " Refused: split point dominated by forbidden block\n"); | |
506 | return; | |
507 | } | |
508 | ||
241a2b9e JH |
509 | /* See if retval used by return bb is computed by header or split part. |
510 | When it is computed by split part, we need to produce return statement | |
511 | in the split part and add code to header to pass it around. | |
512 | ||
513 | This is bit tricky to test: | |
514 | 1) When there is no return_bb or no return value, we always pass | |
515 | value around. | |
516 | 2) Invariants are always computed by caller. | |
517 | 3) For SSA we need to look if defining statement is in header or split part | |
518 | 4) For non-SSA we need to look where the var is computed. */ | |
519 | retval = find_retval (return_bb); | |
520 | if (!retval) | |
521 | current->split_part_set_retval = true; | |
522 | else if (is_gimple_min_invariant (retval)) | |
523 | current->split_part_set_retval = false; | |
524 | /* Special case is value returned by reference we record as if it was non-ssa | |
525 | set to result_decl. */ | |
526 | else if (TREE_CODE (retval) == SSA_NAME | |
527 | && TREE_CODE (SSA_NAME_VAR (retval)) == RESULT_DECL | |
528 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
529 | current->split_part_set_retval | |
530 | = bitmap_bit_p (non_ssa_vars, DECL_UID (SSA_NAME_VAR (retval))); | |
531 | else if (TREE_CODE (retval) == SSA_NAME) | |
532 | current->split_part_set_retval | |
533 | = (!SSA_NAME_IS_DEFAULT_DEF (retval) | |
534 | && (bitmap_bit_p (current->split_bbs, | |
535 | gimple_bb (SSA_NAME_DEF_STMT (retval))->index) | |
536 | || gimple_bb (SSA_NAME_DEF_STMT (retval)) == return_bb)); | |
537 | else if (TREE_CODE (retval) == PARM_DECL) | |
538 | current->split_part_set_retval = false; | |
539 | else if (TREE_CODE (retval) == VAR_DECL | |
540 | || TREE_CODE (retval) == RESULT_DECL) | |
541 | current->split_part_set_retval | |
542 | = bitmap_bit_p (non_ssa_vars, DECL_UID (retval)); | |
543 | else | |
544 | current->split_part_set_retval = true; | |
545 | ||
28fc44f3 JJ |
546 | /* split_function fixes up at most one PHI non-virtual PHI node in return_bb, |
547 | for the return value. If there are other PHIs, give up. */ | |
548 | if (return_bb != EXIT_BLOCK_PTR) | |
549 | { | |
550 | gimple_stmt_iterator psi; | |
551 | ||
552 | for (psi = gsi_start_phis (return_bb); !gsi_end_p (psi); gsi_next (&psi)) | |
553 | if (is_gimple_reg (gimple_phi_result (gsi_stmt (psi))) | |
554 | && !(retval | |
555 | && current->split_part_set_retval | |
556 | && TREE_CODE (retval) == SSA_NAME | |
557 | && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)) | |
558 | && SSA_NAME_DEF_STMT (retval) == gsi_stmt (psi))) | |
559 | { | |
560 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
561 | fprintf (dump_file, | |
562 | " Refused: return bb has extra PHIs\n"); | |
563 | return; | |
564 | } | |
565 | } | |
566 | ||
567 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
568 | fprintf (dump_file, " Accepted!\n"); | |
569 | ||
3e485f62 JH |
570 | /* At the moment chose split point with lowest frequency and that leaves |
571 | out smallest size of header. | |
572 | In future we might re-consider this heuristics. */ | |
573 | if (!best_split_point.split_bbs | |
574 | || best_split_point.entry_bb->frequency > current->entry_bb->frequency | |
575 | || (best_split_point.entry_bb->frequency == current->entry_bb->frequency | |
576 | && best_split_point.split_size < current->split_size)) | |
577 | ||
578 | { | |
579 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
580 | fprintf (dump_file, " New best split point!\n"); | |
581 | if (best_split_point.ssa_names_to_pass) | |
582 | { | |
583 | BITMAP_FREE (best_split_point.ssa_names_to_pass); | |
584 | BITMAP_FREE (best_split_point.split_bbs); | |
585 | } | |
586 | best_split_point = *current; | |
587 | best_split_point.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
588 | bitmap_copy (best_split_point.ssa_names_to_pass, | |
589 | current->ssa_names_to_pass); | |
590 | best_split_point.split_bbs = BITMAP_ALLOC (NULL); | |
591 | bitmap_copy (best_split_point.split_bbs, current->split_bbs); | |
592 | } | |
593 | } | |
594 | ||
2094f1fc JH |
595 | /* Return basic block containing RETURN statement. We allow basic blocks |
596 | of the form: | |
597 | <retval> = tmp_var; | |
598 | return <retval> | |
599 | but return_bb can not be more complex than this. | |
600 | If nothing is found, return EXIT_BLOCK_PTR. | |
601 | ||
3e485f62 JH |
602 | When there are multiple RETURN statement, chose one with return value, |
603 | since that one is more likely shared by multiple code paths. | |
2094f1fc JH |
604 | |
605 | Return BB is special, because for function splitting it is the only | |
606 | basic block that is duplicated in between header and split part of the | |
607 | function. | |
608 | ||
3e485f62 JH |
609 | TODO: We might support multiple return blocks. */ |
610 | ||
611 | static basic_block | |
612 | find_return_bb (void) | |
613 | { | |
614 | edge e; | |
3e485f62 | 615 | basic_block return_bb = EXIT_BLOCK_PTR; |
68457901 JJ |
616 | gimple_stmt_iterator bsi; |
617 | bool found_return = false; | |
618 | tree retval = NULL_TREE; | |
3e485f62 | 619 | |
68457901 JJ |
620 | if (!single_pred_p (EXIT_BLOCK_PTR)) |
621 | return return_bb; | |
622 | ||
623 | e = single_pred_edge (EXIT_BLOCK_PTR); | |
624 | for (bsi = gsi_last_bb (e->src); !gsi_end_p (bsi); gsi_prev (&bsi)) | |
625 | { | |
626 | gimple stmt = gsi_stmt (bsi); | |
a348dc7f JJ |
627 | if (gimple_code (stmt) == GIMPLE_LABEL |
628 | || is_gimple_debug (stmt) | |
629 | || gimple_clobber_p (stmt)) | |
68457901 JJ |
630 | ; |
631 | else if (gimple_code (stmt) == GIMPLE_ASSIGN | |
632 | && found_return | |
633 | && gimple_assign_single_p (stmt) | |
634 | && (auto_var_in_fn_p (gimple_assign_rhs1 (stmt), | |
635 | current_function_decl) | |
636 | || is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) | |
637 | && retval == gimple_assign_lhs (stmt)) | |
638 | ; | |
639 | else if (gimple_code (stmt) == GIMPLE_RETURN) | |
640 | { | |
641 | found_return = true; | |
642 | retval = gimple_return_retval (stmt); | |
643 | } | |
644 | else | |
645 | break; | |
646 | } | |
647 | if (gsi_end_p (bsi) && found_return) | |
648 | return_bb = e->src; | |
3e485f62 | 649 | |
3e485f62 JH |
650 | return return_bb; |
651 | } | |
652 | ||
ed7656f6 | 653 | /* Given return basic block RETURN_BB, see where return value is really |
2094f1fc JH |
654 | stored. */ |
655 | static tree | |
656 | find_retval (basic_block return_bb) | |
657 | { | |
658 | gimple_stmt_iterator bsi; | |
659 | for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
660 | if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) | |
661 | return gimple_return_retval (gsi_stmt (bsi)); | |
a348dc7f JJ |
662 | else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN |
663 | && !gimple_clobber_p (gsi_stmt (bsi))) | |
2094f1fc JH |
664 | return gimple_assign_rhs1 (gsi_stmt (bsi)); |
665 | return NULL; | |
666 | } | |
667 | ||
1802378d EB |
668 | /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
669 | variable, mark it as used in bitmap passed via DATA. | |
3e485f62 JH |
670 | Return true when access to T prevents splitting the function. */ |
671 | ||
672 | static bool | |
1802378d | 673 | mark_nonssa_use (gimple stmt ATTRIBUTE_UNUSED, tree t, void *data) |
3e485f62 JH |
674 | { |
675 | t = get_base_address (t); | |
676 | ||
677 | if (!t || is_gimple_reg (t)) | |
678 | return false; | |
679 | ||
680 | /* At present we can't pass non-SSA arguments to split function. | |
681 | FIXME: this can be relaxed by passing references to arguments. */ | |
682 | if (TREE_CODE (t) == PARM_DECL) | |
683 | { | |
684 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1802378d EB |
685 | fprintf (dump_file, |
686 | "Cannot split: use of non-ssa function parameter.\n"); | |
3e485f62 JH |
687 | return true; |
688 | } | |
689 | ||
1802378d EB |
690 | if ((TREE_CODE (t) == VAR_DECL |
691 | && auto_var_in_fn_p (t, current_function_decl)) | |
692 | || TREE_CODE (t) == RESULT_DECL | |
693 | || TREE_CODE (t) == LABEL_DECL) | |
3e485f62 | 694 | bitmap_set_bit ((bitmap)data, DECL_UID (t)); |
241a2b9e | 695 | |
1802378d EB |
696 | /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
697 | to pretend that the value pointed to is actual result decl. */ | |
698 | if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) | |
241a2b9e JH |
699 | && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
700 | && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL | |
701 | && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
1802378d EB |
702 | return |
703 | bitmap_bit_p ((bitmap)data, | |
704 | DECL_UID (DECL_RESULT (current_function_decl))); | |
705 | ||
3e485f62 JH |
706 | return false; |
707 | } | |
708 | ||
709 | /* Compute local properties of basic block BB we collect when looking for | |
710 | split points. We look for ssa defs and store them in SET_SSA_NAMES, | |
711 | for ssa uses and store them in USED_SSA_NAMES and for any non-SSA automatic | |
712 | vars stored in NON_SSA_VARS. | |
713 | ||
714 | When BB has edge to RETURN_BB, collect uses in RETURN_BB too. | |
715 | ||
716 | Return false when BB contains something that prevents it from being put into | |
717 | split function. */ | |
718 | ||
719 | static bool | |
720 | visit_bb (basic_block bb, basic_block return_bb, | |
721 | bitmap set_ssa_names, bitmap used_ssa_names, | |
722 | bitmap non_ssa_vars) | |
723 | { | |
724 | gimple_stmt_iterator bsi; | |
725 | edge e; | |
726 | edge_iterator ei; | |
727 | bool can_split = true; | |
728 | ||
729 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
730 | { | |
731 | gimple stmt = gsi_stmt (bsi); | |
732 | tree op; | |
733 | ssa_op_iter iter; | |
734 | tree decl; | |
735 | ||
736 | if (is_gimple_debug (stmt)) | |
737 | continue; | |
738 | ||
a348dc7f JJ |
739 | if (gimple_clobber_p (stmt)) |
740 | continue; | |
741 | ||
3e485f62 JH |
742 | /* FIXME: We can split regions containing EH. We can not however |
743 | split RESX, EH_DISPATCH and EH_POINTER referring to same region | |
744 | into different partitions. This would require tracking of | |
745 | EH regions and checking in consider_split_point if they | |
746 | are not used elsewhere. */ | |
1da7d8c0 | 747 | if (gimple_code (stmt) == GIMPLE_RESX) |
3e485f62 JH |
748 | { |
749 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1da7d8c0 | 750 | fprintf (dump_file, "Cannot split: resx.\n"); |
3e485f62 JH |
751 | can_split = false; |
752 | } | |
753 | if (gimple_code (stmt) == GIMPLE_EH_DISPATCH) | |
754 | { | |
755 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1802378d | 756 | fprintf (dump_file, "Cannot split: eh dispatch.\n"); |
3e485f62 JH |
757 | can_split = false; |
758 | } | |
759 | ||
760 | /* Check builtins that prevent splitting. */ | |
761 | if (gimple_code (stmt) == GIMPLE_CALL | |
762 | && (decl = gimple_call_fndecl (stmt)) != NULL_TREE | |
763 | && DECL_BUILT_IN (decl) | |
764 | && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL) | |
765 | switch (DECL_FUNCTION_CODE (decl)) | |
766 | { | |
767 | /* FIXME: once we will allow passing non-parm values to split part, | |
768 | we need to be sure to handle correct builtin_stack_save and | |
769 | builtin_stack_restore. At the moment we are safe; there is no | |
770 | way to store builtin_stack_save result in non-SSA variable | |
771 | since all calls to those are compiler generated. */ | |
772 | case BUILT_IN_APPLY: | |
61e03ffc | 773 | case BUILT_IN_APPLY_ARGS: |
3e485f62 JH |
774 | case BUILT_IN_VA_START: |
775 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1802378d EB |
776 | fprintf (dump_file, |
777 | "Cannot split: builtin_apply and va_start.\n"); | |
3e485f62 JH |
778 | can_split = false; |
779 | break; | |
780 | case BUILT_IN_EH_POINTER: | |
781 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1802378d | 782 | fprintf (dump_file, "Cannot split: builtin_eh_pointer.\n"); |
3e485f62 JH |
783 | can_split = false; |
784 | break; | |
785 | default: | |
786 | break; | |
787 | } | |
788 | ||
789 | FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF) | |
790 | bitmap_set_bit (set_ssa_names, SSA_NAME_VERSION (op)); | |
791 | FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE) | |
792 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
793 | can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, | |
794 | mark_nonssa_use, | |
795 | mark_nonssa_use, | |
796 | mark_nonssa_use); | |
797 | } | |
798 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
799 | { | |
800 | gimple stmt = gsi_stmt (bsi); | |
8b3057b3 | 801 | unsigned int i; |
3e485f62 JH |
802 | |
803 | if (is_gimple_debug (stmt)) | |
804 | continue; | |
805 | if (!is_gimple_reg (gimple_phi_result (stmt))) | |
806 | continue; | |
8b3057b3 JH |
807 | bitmap_set_bit (set_ssa_names, |
808 | SSA_NAME_VERSION (gimple_phi_result (stmt))); | |
809 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
810 | { | |
811 | tree op = gimple_phi_arg_def (stmt, i); | |
812 | if (TREE_CODE (op) == SSA_NAME) | |
813 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
814 | } | |
3e485f62 JH |
815 | can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, |
816 | mark_nonssa_use, | |
817 | mark_nonssa_use, | |
818 | mark_nonssa_use); | |
819 | } | |
ed7656f6 | 820 | /* Record also uses coming from PHI operand in return BB. */ |
3e485f62 JH |
821 | FOR_EACH_EDGE (e, ei, bb->succs) |
822 | if (e->dest == return_bb) | |
823 | { | |
3e485f62 JH |
824 | for (bsi = gsi_start_phis (return_bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
825 | { | |
826 | gimple stmt = gsi_stmt (bsi); | |
827 | tree op = gimple_phi_arg_def (stmt, e->dest_idx); | |
828 | ||
829 | if (is_gimple_debug (stmt)) | |
830 | continue; | |
831 | if (!is_gimple_reg (gimple_phi_result (stmt))) | |
832 | continue; | |
3e485f62 JH |
833 | if (TREE_CODE (op) == SSA_NAME) |
834 | bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); | |
835 | else | |
836 | can_split &= !mark_nonssa_use (stmt, op, non_ssa_vars); | |
837 | } | |
3e485f62 JH |
838 | } |
839 | return can_split; | |
840 | } | |
841 | ||
842 | /* Stack entry for recursive DFS walk in find_split_point. */ | |
843 | ||
844 | typedef struct | |
845 | { | |
846 | /* Basic block we are examining. */ | |
847 | basic_block bb; | |
848 | ||
849 | /* SSA names set and used by the BB and all BBs reachable | |
850 | from it via DFS walk. */ | |
851 | bitmap set_ssa_names, used_ssa_names; | |
852 | bitmap non_ssa_vars; | |
853 | ||
854 | /* All BBS visited from this BB via DFS walk. */ | |
855 | bitmap bbs_visited; | |
856 | ||
857 | /* Last examined edge in DFS walk. Since we walk unoriented graph, | |
ed7656f6 | 858 | the value is up to sum of incoming and outgoing edges of BB. */ |
3e485f62 JH |
859 | unsigned int edge_num; |
860 | ||
861 | /* Stack entry index of earliest BB reachable from current BB | |
ed7656f6 | 862 | or any BB visited later in DFS walk. */ |
3e485f62 JH |
863 | int earliest; |
864 | ||
865 | /* Overall time and size of all BBs reached from this BB in DFS walk. */ | |
866 | int overall_time, overall_size; | |
867 | ||
868 | /* When false we can not split on this BB. */ | |
869 | bool can_split; | |
870 | } stack_entry; | |
871 | DEF_VEC_O(stack_entry); | |
872 | DEF_VEC_ALLOC_O(stack_entry,heap); | |
873 | ||
874 | ||
875 | /* Find all articulations and call consider_split on them. | |
876 | OVERALL_TIME and OVERALL_SIZE is time and size of the function. | |
877 | ||
878 | We perform basic algorithm for finding an articulation in a graph | |
879 | created from CFG by considering it to be an unoriented graph. | |
880 | ||
881 | The articulation is discovered via DFS walk. We collect earliest | |
882 | basic block on stack that is reachable via backward edge. Articulation | |
883 | is any basic block such that there is no backward edge bypassing it. | |
884 | To reduce stack usage we maintain heap allocated stack in STACK vector. | |
885 | AUX pointer of BB is set to index it appears in the stack or -1 once | |
886 | it is visited and popped off the stack. | |
887 | ||
888 | The algorithm finds articulation after visiting the whole component | |
889 | reachable by it. This makes it convenient to collect information about | |
890 | the component used by consider_split. */ | |
891 | ||
892 | static void | |
893 | find_split_points (int overall_time, int overall_size) | |
894 | { | |
895 | stack_entry first; | |
896 | VEC(stack_entry, heap) *stack = NULL; | |
897 | basic_block bb; | |
898 | basic_block return_bb = find_return_bb (); | |
899 | struct split_point current; | |
900 | ||
901 | current.header_time = overall_time; | |
902 | current.header_size = overall_size; | |
903 | current.split_time = 0; | |
904 | current.split_size = 0; | |
905 | current.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
906 | ||
907 | first.bb = ENTRY_BLOCK_PTR; | |
908 | first.edge_num = 0; | |
909 | first.overall_time = 0; | |
910 | first.overall_size = 0; | |
911 | first.earliest = INT_MAX; | |
912 | first.set_ssa_names = 0; | |
913 | first.used_ssa_names = 0; | |
914 | first.bbs_visited = 0; | |
915 | VEC_safe_push (stack_entry, heap, stack, &first); | |
916 | ENTRY_BLOCK_PTR->aux = (void *)(intptr_t)-1; | |
917 | ||
918 | while (!VEC_empty (stack_entry, stack)) | |
919 | { | |
920 | stack_entry *entry = VEC_last (stack_entry, stack); | |
921 | ||
922 | /* We are walking an acyclic graph, so edge_num counts | |
923 | succ and pred edges together. However when considering | |
924 | articulation, we want to have processed everything reachable | |
925 | from articulation but nothing that reaches into it. */ | |
926 | if (entry->edge_num == EDGE_COUNT (entry->bb->succs) | |
927 | && entry->bb != ENTRY_BLOCK_PTR) | |
928 | { | |
929 | int pos = VEC_length (stack_entry, stack); | |
930 | entry->can_split &= visit_bb (entry->bb, return_bb, | |
931 | entry->set_ssa_names, | |
932 | entry->used_ssa_names, | |
933 | entry->non_ssa_vars); | |
934 | if (pos <= entry->earliest && !entry->can_split | |
935 | && dump_file && (dump_flags & TDF_DETAILS)) | |
936 | fprintf (dump_file, | |
937 | "found articulation at bb %i but can not split\n", | |
938 | entry->bb->index); | |
939 | if (pos <= entry->earliest && entry->can_split) | |
940 | { | |
941 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
942 | fprintf (dump_file, "found articulation at bb %i\n", | |
943 | entry->bb->index); | |
944 | current.entry_bb = entry->bb; | |
945 | current.ssa_names_to_pass = BITMAP_ALLOC (NULL); | |
946 | bitmap_and_compl (current.ssa_names_to_pass, | |
947 | entry->used_ssa_names, entry->set_ssa_names); | |
948 | current.header_time = overall_time - entry->overall_time; | |
949 | current.header_size = overall_size - entry->overall_size; | |
950 | current.split_time = entry->overall_time; | |
951 | current.split_size = entry->overall_size; | |
952 | current.split_bbs = entry->bbs_visited; | |
953 | consider_split (¤t, entry->non_ssa_vars, return_bb); | |
954 | BITMAP_FREE (current.ssa_names_to_pass); | |
955 | } | |
956 | } | |
957 | /* Do actual DFS walk. */ | |
958 | if (entry->edge_num | |
959 | < (EDGE_COUNT (entry->bb->succs) | |
960 | + EDGE_COUNT (entry->bb->preds))) | |
961 | { | |
962 | edge e; | |
963 | basic_block dest; | |
964 | if (entry->edge_num < EDGE_COUNT (entry->bb->succs)) | |
965 | { | |
966 | e = EDGE_SUCC (entry->bb, entry->edge_num); | |
967 | dest = e->dest; | |
968 | } | |
969 | else | |
970 | { | |
971 | e = EDGE_PRED (entry->bb, entry->edge_num | |
972 | - EDGE_COUNT (entry->bb->succs)); | |
973 | dest = e->src; | |
974 | } | |
975 | ||
976 | entry->edge_num++; | |
977 | ||
978 | /* New BB to visit, push it to the stack. */ | |
979 | if (dest != return_bb && dest != EXIT_BLOCK_PTR | |
980 | && !dest->aux) | |
981 | { | |
982 | stack_entry new_entry; | |
983 | ||
984 | new_entry.bb = dest; | |
985 | new_entry.edge_num = 0; | |
986 | new_entry.overall_time | |
987 | = VEC_index (bb_info, bb_info_vec, dest->index)->time; | |
988 | new_entry.overall_size | |
989 | = VEC_index (bb_info, bb_info_vec, dest->index)->size; | |
990 | new_entry.earliest = INT_MAX; | |
991 | new_entry.set_ssa_names = BITMAP_ALLOC (NULL); | |
992 | new_entry.used_ssa_names = BITMAP_ALLOC (NULL); | |
993 | new_entry.bbs_visited = BITMAP_ALLOC (NULL); | |
994 | new_entry.non_ssa_vars = BITMAP_ALLOC (NULL); | |
995 | new_entry.can_split = true; | |
996 | bitmap_set_bit (new_entry.bbs_visited, dest->index); | |
997 | VEC_safe_push (stack_entry, heap, stack, &new_entry); | |
998 | dest->aux = (void *)(intptr_t)VEC_length (stack_entry, stack); | |
999 | } | |
1000 | /* Back edge found, record the earliest point. */ | |
1001 | else if ((intptr_t)dest->aux > 0 | |
1002 | && (intptr_t)dest->aux < entry->earliest) | |
1003 | entry->earliest = (intptr_t)dest->aux; | |
1004 | } | |
ed7656f6 JJ |
1005 | /* We are done with examining the edges. Pop off the value from stack |
1006 | and merge stuff we accumulate during the walk. */ | |
3e485f62 JH |
1007 | else if (entry->bb != ENTRY_BLOCK_PTR) |
1008 | { | |
1009 | stack_entry *prev = VEC_index (stack_entry, stack, | |
1010 | VEC_length (stack_entry, stack) - 2); | |
1011 | ||
1012 | entry->bb->aux = (void *)(intptr_t)-1; | |
1013 | prev->can_split &= entry->can_split; | |
1014 | if (prev->set_ssa_names) | |
1015 | { | |
1016 | bitmap_ior_into (prev->set_ssa_names, entry->set_ssa_names); | |
1017 | bitmap_ior_into (prev->used_ssa_names, entry->used_ssa_names); | |
1018 | bitmap_ior_into (prev->bbs_visited, entry->bbs_visited); | |
1019 | bitmap_ior_into (prev->non_ssa_vars, entry->non_ssa_vars); | |
1020 | } | |
1021 | if (prev->earliest > entry->earliest) | |
1022 | prev->earliest = entry->earliest; | |
1023 | prev->overall_time += entry->overall_time; | |
1024 | prev->overall_size += entry->overall_size; | |
1025 | BITMAP_FREE (entry->set_ssa_names); | |
1026 | BITMAP_FREE (entry->used_ssa_names); | |
1027 | BITMAP_FREE (entry->bbs_visited); | |
1028 | BITMAP_FREE (entry->non_ssa_vars); | |
1029 | VEC_pop (stack_entry, stack); | |
1030 | } | |
1031 | else | |
1032 | VEC_pop (stack_entry, stack); | |
1033 | } | |
1034 | ENTRY_BLOCK_PTR->aux = NULL; | |
1035 | FOR_EACH_BB (bb) | |
1036 | bb->aux = NULL; | |
ff61e417 | 1037 | VEC_free (stack_entry, heap, stack); |
3e485f62 JH |
1038 | BITMAP_FREE (current.ssa_names_to_pass); |
1039 | } | |
1040 | ||
1041 | /* Split function at SPLIT_POINT. */ | |
1042 | ||
1043 | static void | |
1044 | split_function (struct split_point *split_point) | |
1045 | { | |
1046 | VEC (tree, heap) *args_to_pass = NULL; | |
201176d3 | 1047 | bitmap args_to_skip; |
3e485f62 JH |
1048 | tree parm; |
1049 | int num = 0; | |
201176d3 | 1050 | struct cgraph_node *node, *cur_node = cgraph_get_node (current_function_decl); |
3e485f62 JH |
1051 | basic_block return_bb = find_return_bb (); |
1052 | basic_block call_bb; | |
1053 | gimple_stmt_iterator gsi; | |
1054 | gimple call; | |
1055 | edge e; | |
1056 | edge_iterator ei; | |
1057 | tree retval = NULL, real_retval = NULL; | |
1058 | bool split_part_return_p = false; | |
1059 | gimple last_stmt = NULL; | |
371556ee JJ |
1060 | unsigned int i; |
1061 | tree arg; | |
3e485f62 JH |
1062 | |
1063 | if (dump_file) | |
1064 | { | |
1065 | fprintf (dump_file, "\n\nSplitting function at:\n"); | |
1066 | dump_split_point (dump_file, split_point); | |
1067 | } | |
1068 | ||
201176d3 MJ |
1069 | if (cur_node->local.can_change_signature) |
1070 | args_to_skip = BITMAP_ALLOC (NULL); | |
1071 | else | |
1072 | args_to_skip = NULL; | |
1073 | ||
3e485f62 JH |
1074 | /* Collect the parameters of new function and args_to_skip bitmap. */ |
1075 | for (parm = DECL_ARGUMENTS (current_function_decl); | |
910ad8de | 1076 | parm; parm = DECL_CHAIN (parm), num++) |
201176d3 MJ |
1077 | if (args_to_skip |
1078 | && (!is_gimple_reg (parm) | |
1079 | || !gimple_default_def (cfun, parm) | |
1080 | || !bitmap_bit_p (split_point->ssa_names_to_pass, | |
1081 | SSA_NAME_VERSION (gimple_default_def (cfun, | |
1082 | parm))))) | |
3e485f62 JH |
1083 | bitmap_set_bit (args_to_skip, num); |
1084 | else | |
371556ee | 1085 | { |
86814190 MJ |
1086 | /* This parm might not have been used up to now, but is going to be |
1087 | used, hence register it. */ | |
1088 | add_referenced_var (parm); | |
1089 | if (is_gimple_reg (parm)) | |
201176d3 | 1090 | { |
86814190 MJ |
1091 | arg = gimple_default_def (cfun, parm); |
1092 | if (!arg) | |
1093 | { | |
1094 | arg = make_ssa_name (parm, gimple_build_nop ()); | |
1095 | set_default_def (parm, arg); | |
1096 | } | |
201176d3 | 1097 | } |
86814190 MJ |
1098 | else |
1099 | arg = parm; | |
201176d3 | 1100 | |
2b3c0885 RG |
1101 | if (!useless_type_conversion_p (DECL_ARG_TYPE (parm), TREE_TYPE (arg))) |
1102 | arg = fold_convert (DECL_ARG_TYPE (parm), arg); | |
371556ee JJ |
1103 | VEC_safe_push (tree, heap, args_to_pass, arg); |
1104 | } | |
3e485f62 JH |
1105 | |
1106 | /* See if the split function will return. */ | |
1107 | FOR_EACH_EDGE (e, ei, return_bb->preds) | |
1108 | if (bitmap_bit_p (split_point->split_bbs, e->src->index)) | |
1109 | break; | |
1110 | if (e) | |
1111 | split_part_return_p = true; | |
1112 | ||
241a2b9e JH |
1113 | /* Add return block to what will become the split function. |
1114 | We do not return; no return block is needed. */ | |
1115 | if (!split_part_return_p) | |
1116 | ; | |
1117 | /* We have no return block, so nothing is needed. */ | |
1118 | else if (return_bb == EXIT_BLOCK_PTR) | |
1119 | ; | |
1120 | /* When we do not want to return value, we need to construct | |
1121 | new return block with empty return statement. | |
1122 | FIXME: Once we are able to change return type, we should change function | |
1123 | to return void instead of just outputting function with undefined return | |
1124 | value. For structures this affects quality of codegen. */ | |
1125 | else if (!split_point->split_part_set_retval | |
1126 | && find_retval (return_bb)) | |
1127 | { | |
1128 | bool redirected = true; | |
1129 | basic_block new_return_bb = create_basic_block (NULL, 0, return_bb); | |
1130 | gimple_stmt_iterator gsi = gsi_start_bb (new_return_bb); | |
1131 | gsi_insert_after (&gsi, gimple_build_return (NULL), GSI_NEW_STMT); | |
1132 | while (redirected) | |
1133 | { | |
1134 | redirected = false; | |
1135 | FOR_EACH_EDGE (e, ei, return_bb->preds) | |
1136 | if (bitmap_bit_p (split_point->split_bbs, e->src->index)) | |
1137 | { | |
1138 | new_return_bb->count += e->count; | |
1139 | new_return_bb->frequency += EDGE_FREQUENCY (e); | |
1140 | redirect_edge_and_branch (e, new_return_bb); | |
1141 | redirected = true; | |
1142 | break; | |
1143 | } | |
1144 | } | |
1145 | e = make_edge (new_return_bb, EXIT_BLOCK_PTR, 0); | |
1146 | e->probability = REG_BR_PROB_BASE; | |
1147 | e->count = new_return_bb->count; | |
1148 | bitmap_set_bit (split_point->split_bbs, new_return_bb->index); | |
2e5e346d JL |
1149 | } |
1150 | /* When we pass around the value, use existing return block. */ | |
1151 | else | |
1152 | bitmap_set_bit (split_point->split_bbs, return_bb->index); | |
1153 | ||
1154 | /* If RETURN_BB has virtual operand PHIs, they must be removed and the | |
1155 | virtual operand marked for renaming as we change the CFG in a way that | |
cfef45c8 | 1156 | tree-inline is not able to compensate for. |
2e5e346d JL |
1157 | |
1158 | Note this can happen whether or not we have a return value. If we have | |
1159 | a return value, then RETURN_BB may have PHIs for real operands too. */ | |
1160 | if (return_bb != EXIT_BLOCK_PTR) | |
1161 | { | |
cfef45c8 | 1162 | bool phi_p = false; |
241a2b9e JH |
1163 | for (gsi = gsi_start_phis (return_bb); !gsi_end_p (gsi);) |
1164 | { | |
1165 | gimple stmt = gsi_stmt (gsi); | |
2e5e346d JL |
1166 | if (is_gimple_reg (gimple_phi_result (stmt))) |
1167 | { | |
1168 | gsi_next (&gsi); | |
1169 | continue; | |
1170 | } | |
6b8c9df8 RG |
1171 | mark_virtual_phi_result_for_renaming (stmt); |
1172 | remove_phi_node (&gsi, true); | |
cfef45c8 | 1173 | phi_p = true; |
241a2b9e | 1174 | } |
cfef45c8 RG |
1175 | /* In reality we have to rename the reaching definition of the |
1176 | virtual operand at return_bb as we will eventually release it | |
1177 | when we remove the code region we outlined. | |
1178 | So we have to rename all immediate virtual uses of that region | |
1179 | if we didn't see a PHI definition yet. */ | |
1180 | /* ??? In real reality we want to set the reaching vdef of the | |
1181 | entry of the SESE region as the vuse of the call and the reaching | |
1182 | vdef of the exit of the SESE region as the vdef of the call. */ | |
1183 | if (!phi_p) | |
1184 | for (gsi = gsi_start_bb (return_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1185 | { | |
1186 | gimple stmt = gsi_stmt (gsi); | |
1187 | if (gimple_vuse (stmt)) | |
1188 | { | |
1189 | gimple_set_vuse (stmt, NULL_TREE); | |
1190 | update_stmt (stmt); | |
1191 | } | |
1192 | if (gimple_vdef (stmt)) | |
1193 | break; | |
1194 | } | |
241a2b9e | 1195 | } |
3e485f62 JH |
1196 | |
1197 | /* Now create the actual clone. */ | |
1198 | rebuild_cgraph_edges (); | |
201176d3 | 1199 | node = cgraph_function_versioning (cur_node, NULL, NULL, args_to_skip, |
1a2c27e9 | 1200 | !split_part_return_p, |
3e485f62 | 1201 | split_point->split_bbs, |
2094f1fc | 1202 | split_point->entry_bb, "part"); |
d402c33d JH |
1203 | /* For usual cloning it is enough to clear builtin only when signature |
1204 | changes. For partial inlining we however can not expect the part | |
1205 | of builtin implementation to have same semantic as the whole. */ | |
1206 | if (DECL_BUILT_IN (node->decl)) | |
1207 | { | |
1208 | DECL_BUILT_IN_CLASS (node->decl) = NOT_BUILT_IN; | |
1209 | DECL_FUNCTION_CODE (node->decl) = (enum built_in_function) 0; | |
1210 | } | |
201176d3 | 1211 | cgraph_node_remove_callees (cur_node); |
3e485f62 JH |
1212 | if (!split_part_return_p) |
1213 | TREE_THIS_VOLATILE (node->decl) = 1; | |
1214 | if (dump_file) | |
1215 | dump_function_to_file (node->decl, dump_file, dump_flags); | |
1216 | ||
1217 | /* Create the basic block we place call into. It is the entry basic block | |
1218 | split after last label. */ | |
1219 | call_bb = split_point->entry_bb; | |
1220 | for (gsi = gsi_start_bb (call_bb); !gsi_end_p (gsi);) | |
1221 | if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL) | |
1222 | { | |
1223 | last_stmt = gsi_stmt (gsi); | |
1224 | gsi_next (&gsi); | |
1225 | } | |
1226 | else | |
1227 | break; | |
1228 | e = split_block (split_point->entry_bb, last_stmt); | |
1229 | remove_edge (e); | |
1230 | ||
1231 | /* Produce the call statement. */ | |
1232 | gsi = gsi_last_bb (call_bb); | |
2b3c0885 RG |
1233 | FOR_EACH_VEC_ELT (tree, args_to_pass, i, arg) |
1234 | if (!is_gimple_val (arg)) | |
1235 | { | |
1236 | arg = force_gimple_operand_gsi (&gsi, arg, true, NULL_TREE, | |
f6e52e91 | 1237 | false, GSI_CONTINUE_LINKING); |
2b3c0885 RG |
1238 | VEC_replace (tree, args_to_pass, i, arg); |
1239 | } | |
3e485f62 JH |
1240 | call = gimple_build_call_vec (node->decl, args_to_pass); |
1241 | gimple_set_block (call, DECL_INITIAL (current_function_decl)); | |
1242 | ||
556e9ba0 JH |
1243 | /* We avoid address being taken on any variable used by split part, |
1244 | so return slot optimization is always possible. Moreover this is | |
1245 | required to make DECL_BY_REFERENCE work. */ | |
1246 | if (aggregate_value_p (DECL_RESULT (current_function_decl), | |
1247 | TREE_TYPE (current_function_decl))) | |
1248 | gimple_call_set_return_slot_opt (call, true); | |
1249 | ||
3e485f62 JH |
1250 | /* Update return value. This is bit tricky. When we do not return, |
1251 | do nothing. When we return we might need to update return_bb | |
1252 | or produce a new return statement. */ | |
1253 | if (!split_part_return_p) | |
1254 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1255 | else | |
1256 | { | |
1257 | e = make_edge (call_bb, return_bb, | |
1258 | return_bb == EXIT_BLOCK_PTR ? 0 : EDGE_FALLTHRU); | |
1259 | e->count = call_bb->count; | |
1260 | e->probability = REG_BR_PROB_BASE; | |
6938f93f JH |
1261 | |
1262 | /* If there is return basic block, see what value we need to store | |
1263 | return value into and put call just before it. */ | |
3e485f62 JH |
1264 | if (return_bb != EXIT_BLOCK_PTR) |
1265 | { | |
2094f1fc | 1266 | real_retval = retval = find_retval (return_bb); |
6938f93f | 1267 | |
241a2b9e | 1268 | if (real_retval && split_point->split_part_set_retval) |
3e485f62 JH |
1269 | { |
1270 | gimple_stmt_iterator psi; | |
1271 | ||
6938f93f JH |
1272 | /* See if we need new SSA_NAME for the result. |
1273 | When DECL_BY_REFERENCE is true, retval is actually pointer to | |
1274 | return value and it is constant in whole function. */ | |
1275 | if (TREE_CODE (retval) == SSA_NAME | |
1276 | && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) | |
3e485f62 JH |
1277 | { |
1278 | retval = make_ssa_name (SSA_NAME_VAR (retval), call); | |
6938f93f JH |
1279 | |
1280 | /* See if there is PHI defining return value. */ | |
1281 | for (psi = gsi_start_phis (return_bb); | |
1282 | !gsi_end_p (psi); gsi_next (&psi)) | |
1283 | if (is_gimple_reg (gimple_phi_result (gsi_stmt (psi)))) | |
1284 | break; | |
1285 | ||
1286 | /* When there is PHI, just update its value. */ | |
3e485f62 JH |
1287 | if (TREE_CODE (retval) == SSA_NAME |
1288 | && !gsi_end_p (psi)) | |
1289 | add_phi_arg (gsi_stmt (psi), retval, e, UNKNOWN_LOCATION); | |
6938f93f JH |
1290 | /* Otherwise update the return BB itself. |
1291 | find_return_bb allows at most one assignment to return value, | |
1292 | so update first statement. */ | |
1293 | else | |
3e485f62 | 1294 | { |
2094f1fc JH |
1295 | gimple_stmt_iterator bsi; |
1296 | for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); | |
1297 | gsi_next (&bsi)) | |
1298 | if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) | |
1299 | { | |
1300 | gimple_return_set_retval (gsi_stmt (bsi), retval); | |
1301 | break; | |
1302 | } | |
1303 | else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN) | |
1304 | { | |
1305 | gimple_assign_set_rhs1 (gsi_stmt (bsi), retval); | |
1306 | break; | |
1307 | } | |
1308 | update_stmt (gsi_stmt (bsi)); | |
3e485f62 JH |
1309 | } |
1310 | } | |
556e9ba0 | 1311 | if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
42b05b6e RG |
1312 | { |
1313 | gimple_call_set_lhs (call, build_simple_mem_ref (retval)); | |
1314 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1315 | } | |
556e9ba0 | 1316 | else |
42b05b6e RG |
1317 | { |
1318 | tree restype; | |
1319 | restype = TREE_TYPE (DECL_RESULT (current_function_decl)); | |
1320 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1321 | if (!useless_type_conversion_p (TREE_TYPE (retval), restype)) | |
1322 | { | |
1323 | gimple cpy; | |
1324 | tree tem = create_tmp_reg (restype, NULL); | |
1325 | tem = make_ssa_name (tem, call); | |
1326 | cpy = gimple_build_assign_with_ops (NOP_EXPR, retval, | |
1327 | tem, NULL_TREE); | |
1328 | gsi_insert_after (&gsi, cpy, GSI_NEW_STMT); | |
1329 | retval = tem; | |
1330 | } | |
1331 | gimple_call_set_lhs (call, retval); | |
1332 | update_stmt (call); | |
1333 | } | |
3e485f62 | 1334 | } |
42b05b6e RG |
1335 | else |
1336 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
3e485f62 | 1337 | } |
6938f93f JH |
1338 | /* We don't use return block (there is either no return in function or |
1339 | multiple of them). So create new basic block with return statement. | |
1340 | */ | |
3e485f62 JH |
1341 | else |
1342 | { | |
1343 | gimple ret; | |
241a2b9e JH |
1344 | if (split_point->split_part_set_retval |
1345 | && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))) | |
3e485f62 | 1346 | { |
4021f4a1 | 1347 | retval = DECL_RESULT (current_function_decl); |
8a9c1ae6 JH |
1348 | |
1349 | /* We use temporary register to hold value when aggregate_value_p | |
1350 | is false. Similarly for DECL_BY_REFERENCE we must avoid extra | |
1351 | copy. */ | |
1352 | if (!aggregate_value_p (retval, TREE_TYPE (current_function_decl)) | |
1353 | && !DECL_BY_REFERENCE (retval)) | |
1354 | retval = create_tmp_reg (TREE_TYPE (retval), NULL); | |
3e485f62 | 1355 | if (is_gimple_reg (retval)) |
6938f93f JH |
1356 | { |
1357 | /* When returning by reference, there is only one SSA name | |
1358 | assigned to RESULT_DECL (that is pointer to return value). | |
1359 | Look it up or create new one if it is missing. */ | |
1360 | if (DECL_BY_REFERENCE (retval)) | |
1361 | { | |
1362 | tree retval_name; | |
1363 | if ((retval_name = gimple_default_def (cfun, retval)) | |
1364 | != NULL) | |
1365 | retval = retval_name; | |
1366 | else | |
1367 | { | |
1368 | retval_name = make_ssa_name (retval, | |
1369 | gimple_build_nop ()); | |
1370 | set_default_def (retval, retval_name); | |
1371 | retval = retval_name; | |
1372 | } | |
1373 | } | |
1374 | /* Otherwise produce new SSA name for return value. */ | |
1375 | else | |
1376 | retval = make_ssa_name (retval, call); | |
1377 | } | |
556e9ba0 JH |
1378 | if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
1379 | gimple_call_set_lhs (call, build_simple_mem_ref (retval)); | |
1380 | else | |
1381 | gimple_call_set_lhs (call, retval); | |
3e485f62 JH |
1382 | } |
1383 | gsi_insert_after (&gsi, call, GSI_NEW_STMT); | |
1384 | ret = gimple_build_return (retval); | |
1385 | gsi_insert_after (&gsi, ret, GSI_NEW_STMT); | |
1386 | } | |
1387 | } | |
1388 | free_dominance_info (CDI_DOMINATORS); | |
1389 | free_dominance_info (CDI_POST_DOMINATORS); | |
632b4f8e | 1390 | compute_inline_parameters (node, true); |
3e485f62 JH |
1391 | } |
1392 | ||
1393 | /* Execute function splitting pass. */ | |
1394 | ||
1395 | static unsigned int | |
1396 | execute_split_functions (void) | |
1397 | { | |
1398 | gimple_stmt_iterator bsi; | |
1399 | basic_block bb; | |
1400 | int overall_time = 0, overall_size = 0; | |
1401 | int todo = 0; | |
581985d7 | 1402 | struct cgraph_node *node = cgraph_get_node (current_function_decl); |
3e485f62 | 1403 | |
b2d2adc6 RG |
1404 | if (flags_from_decl_or_type (current_function_decl) |
1405 | & (ECF_NORETURN|ECF_MALLOC)) | |
3e485f62 JH |
1406 | { |
1407 | if (dump_file) | |
b2d2adc6 | 1408 | fprintf (dump_file, "Not splitting: noreturn/malloc function.\n"); |
3e485f62 JH |
1409 | return 0; |
1410 | } | |
1411 | if (MAIN_NAME_P (DECL_NAME (current_function_decl))) | |
1412 | { | |
1413 | if (dump_file) | |
1414 | fprintf (dump_file, "Not splitting: main function.\n"); | |
1415 | return 0; | |
1416 | } | |
1417 | /* This can be relaxed; function might become inlinable after splitting | |
1418 | away the uninlinable part. */ | |
e7f23018 | 1419 | if (!inline_summary (node)->inlinable) |
3e485f62 JH |
1420 | { |
1421 | if (dump_file) | |
1422 | fprintf (dump_file, "Not splitting: not inlinable.\n"); | |
1423 | return 0; | |
1424 | } | |
e7f23018 | 1425 | if (DECL_DISREGARD_INLINE_LIMITS (node->decl)) |
3e485f62 JH |
1426 | { |
1427 | if (dump_file) | |
ed7656f6 | 1428 | fprintf (dump_file, "Not splitting: disregarding inline limits.\n"); |
3e485f62 JH |
1429 | return 0; |
1430 | } | |
1431 | /* This can be relaxed; most of versioning tests actually prevents | |
1432 | a duplication. */ | |
1433 | if (!tree_versionable_function_p (current_function_decl)) | |
1434 | { | |
1435 | if (dump_file) | |
1436 | fprintf (dump_file, "Not splitting: not versionable.\n"); | |
1437 | return 0; | |
1438 | } | |
1439 | /* FIXME: we could support this. */ | |
1440 | if (DECL_STRUCT_FUNCTION (current_function_decl)->static_chain_decl) | |
1441 | { | |
1442 | if (dump_file) | |
1443 | fprintf (dump_file, "Not splitting: nested function.\n"); | |
1444 | return 0; | |
1445 | } | |
3e485f62 JH |
1446 | |
1447 | /* See if it makes sense to try to split. | |
1448 | It makes sense to split if we inline, that is if we have direct calls to | |
1449 | handle or direct calls are possibly going to appear as result of indirect | |
cf9712cc JH |
1450 | inlining or LTO. Also handle -fprofile-generate as LTO to allow non-LTO |
1451 | training for LTO -fprofile-use build. | |
1452 | ||
3e485f62 JH |
1453 | Note that we are not completely conservative about disqualifying functions |
1454 | called once. It is possible that the caller is called more then once and | |
1455 | then inlining would still benefit. */ | |
1456 | if ((!node->callers || !node->callers->next_caller) | |
1457 | && !node->address_taken | |
014d92e1 | 1458 | && (!flag_lto || !node->local.externally_visible)) |
3e485f62 JH |
1459 | { |
1460 | if (dump_file) | |
1461 | fprintf (dump_file, "Not splitting: not called directly " | |
1462 | "or called once.\n"); | |
1463 | return 0; | |
1464 | } | |
1465 | ||
1466 | /* FIXME: We can actually split if splitting reduces call overhead. */ | |
1467 | if (!flag_inline_small_functions | |
1468 | && !DECL_DECLARED_INLINE_P (current_function_decl)) | |
1469 | { | |
1470 | if (dump_file) | |
1471 | fprintf (dump_file, "Not splitting: not autoinlining and function" | |
1472 | " is not inline.\n"); | |
1473 | return 0; | |
1474 | } | |
1475 | ||
b2e25729 BS |
1476 | /* Initialize bitmap to track forbidden calls. */ |
1477 | forbidden_dominators = BITMAP_ALLOC (NULL); | |
1478 | calculate_dominance_info (CDI_DOMINATORS); | |
1479 | ||
3e485f62 JH |
1480 | /* Compute local info about basic blocks and determine function size/time. */ |
1481 | VEC_safe_grow_cleared (bb_info, heap, bb_info_vec, last_basic_block + 1); | |
1482 | memset (&best_split_point, 0, sizeof (best_split_point)); | |
1483 | FOR_EACH_BB (bb) | |
1484 | { | |
1485 | int time = 0; | |
1486 | int size = 0; | |
1487 | int freq = compute_call_stmt_bb_frequency (current_function_decl, bb); | |
1488 | ||
1489 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1490 | fprintf (dump_file, "Basic block %i\n", bb->index); | |
1491 | ||
1492 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1493 | { | |
1494 | int this_time, this_size; | |
1495 | gimple stmt = gsi_stmt (bsi); | |
1496 | ||
1497 | this_size = estimate_num_insns (stmt, &eni_size_weights); | |
1498 | this_time = estimate_num_insns (stmt, &eni_time_weights) * freq; | |
1499 | size += this_size; | |
1500 | time += this_time; | |
b2e25729 | 1501 | check_forbidden_calls (stmt); |
3e485f62 JH |
1502 | |
1503 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1504 | { | |
1505 | fprintf (dump_file, " freq:%6i size:%3i time:%3i ", | |
1506 | freq, this_size, this_time); | |
1507 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1508 | } | |
1509 | } | |
1510 | overall_time += time; | |
1511 | overall_size += size; | |
1512 | VEC_index (bb_info, bb_info_vec, bb->index)->time = time; | |
1513 | VEC_index (bb_info, bb_info_vec, bb->index)->size = size; | |
1514 | } | |
1515 | find_split_points (overall_time, overall_size); | |
1516 | if (best_split_point.split_bbs) | |
1517 | { | |
1518 | split_function (&best_split_point); | |
1519 | BITMAP_FREE (best_split_point.ssa_names_to_pass); | |
1520 | BITMAP_FREE (best_split_point.split_bbs); | |
1521 | todo = TODO_update_ssa | TODO_cleanup_cfg; | |
1522 | } | |
b2e25729 | 1523 | BITMAP_FREE (forbidden_dominators); |
3e485f62 JH |
1524 | VEC_free (bb_info, heap, bb_info_vec); |
1525 | bb_info_vec = NULL; | |
1526 | return todo; | |
1527 | } | |
1528 | ||
cf9712cc JH |
1529 | /* Gate function splitting pass. When doing profile feedback, we want |
1530 | to execute the pass after profiling is read. So disable one in | |
1531 | early optimization. */ | |
1532 | ||
3e485f62 JH |
1533 | static bool |
1534 | gate_split_functions (void) | |
1535 | { | |
cf9712cc JH |
1536 | return (flag_partial_inlining |
1537 | && !profile_arc_flag && !flag_branch_probabilities); | |
3e485f62 JH |
1538 | } |
1539 | ||
1540 | struct gimple_opt_pass pass_split_functions = | |
1541 | { | |
1542 | { | |
1543 | GIMPLE_PASS, | |
1544 | "fnsplit", /* name */ | |
1545 | gate_split_functions, /* gate */ | |
1546 | execute_split_functions, /* execute */ | |
1547 | NULL, /* sub */ | |
1548 | NULL, /* next */ | |
1549 | 0, /* static_pass_number */ | |
1550 | TV_IPA_FNSPLIT, /* tv_id */ | |
1551 | PROP_cfg, /* properties_required */ | |
1552 | 0, /* properties_provided */ | |
1553 | 0, /* properties_destroyed */ | |
1554 | 0, /* todo_flags_start */ | |
40b6510f | 1555 | TODO_verify_all /* todo_flags_finish */ |
3e485f62 JH |
1556 | } |
1557 | }; | |
cf9712cc JH |
1558 | |
1559 | /* Gate feedback driven function splitting pass. | |
1560 | We don't need to split when profiling at all, we are producing | |
1561 | lousy code anyway. */ | |
1562 | ||
1563 | static bool | |
1564 | gate_feedback_split_functions (void) | |
1565 | { | |
1566 | return (flag_partial_inlining | |
1567 | && flag_branch_probabilities); | |
1568 | } | |
1569 | ||
1570 | /* Execute function splitting pass. */ | |
1571 | ||
1572 | static unsigned int | |
1573 | execute_feedback_split_functions (void) | |
1574 | { | |
1575 | unsigned int retval = execute_split_functions (); | |
1576 | if (retval) | |
1577 | retval |= TODO_rebuild_cgraph_edges; | |
1578 | return retval; | |
1579 | } | |
1580 | ||
1581 | struct gimple_opt_pass pass_feedback_split_functions = | |
1582 | { | |
1583 | { | |
1584 | GIMPLE_PASS, | |
1585 | "feedback_fnsplit", /* name */ | |
1586 | gate_feedback_split_functions, /* gate */ | |
1587 | execute_feedback_split_functions, /* execute */ | |
1588 | NULL, /* sub */ | |
1589 | NULL, /* next */ | |
1590 | 0, /* static_pass_number */ | |
1591 | TV_IPA_FNSPLIT, /* tv_id */ | |
1592 | PROP_cfg, /* properties_required */ | |
1593 | 0, /* properties_provided */ | |
1594 | 0, /* properties_destroyed */ | |
1595 | 0, /* todo_flags_start */ | |
40b6510f | 1596 | TODO_verify_all /* todo_flags_finish */ |
cf9712cc JH |
1597 | } |
1598 | }; |