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1 | /* Driver of optimization process | |
2 | Copyright (C) 2003-2014 Free Software Foundation, Inc. | |
3 | Contributed by Jan Hubicka | |
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 | /* This module implements main driver of compilation process. | |
22 | ||
23 | The main scope of this file is to act as an interface in between | |
24 | tree based frontends and the backend. | |
25 | ||
26 | The front-end is supposed to use following functionality: | |
27 | ||
28 | - cgraph_finalize_function | |
29 | ||
30 | This function is called once front-end has parsed whole body of function | |
31 | and it is certain that the function body nor the declaration will change. | |
32 | ||
33 | (There is one exception needed for implementing GCC extern inline | |
34 | function.) | |
35 | ||
36 | - varpool_finalize_decl | |
37 | ||
38 | This function has same behavior as the above but is used for static | |
39 | variables. | |
40 | ||
41 | - add_asm_node | |
42 | ||
43 | Insert new toplevel ASM statement | |
44 | ||
45 | - finalize_compilation_unit | |
46 | ||
47 | This function is called once (source level) compilation unit is finalized | |
48 | and it will no longer change. | |
49 | ||
50 | The symbol table is constructed starting from the trivially needed | |
51 | symbols finalized by the frontend. Functions are lowered into | |
52 | GIMPLE representation and callgraph/reference lists are constructed. | |
53 | Those are used to discover other necessary functions and variables. | |
54 | ||
55 | At the end the bodies of unreachable functions are removed. | |
56 | ||
57 | The function can be called multiple times when multiple source level | |
58 | compilation units are combined. | |
59 | ||
60 | - compile | |
61 | ||
62 | This passes control to the back-end. Optimizations are performed and | |
63 | final assembler is generated. This is done in the following way. Note | |
64 | that with link time optimization the process is split into three | |
65 | stages (compile time, linktime analysis and parallel linktime as | |
66 | indicated bellow). | |
67 | ||
68 | Compile time: | |
69 | ||
70 | 1) Inter-procedural optimization. | |
71 | (ipa_passes) | |
72 | ||
73 | This part is further split into: | |
74 | ||
75 | a) early optimizations. These are local passes executed in | |
76 | the topological order on the callgraph. | |
77 | ||
78 | The purpose of early optimiations is to optimize away simple | |
79 | things that may otherwise confuse IP analysis. Very simple | |
80 | propagation across the callgraph is done i.e. to discover | |
81 | functions without side effects and simple inlining is performed. | |
82 | ||
83 | b) early small interprocedural passes. | |
84 | ||
85 | Those are interprocedural passes executed only at compilation | |
86 | time. These include, for example, transational memory lowering, | |
87 | unreachable code removal and other simple transformations. | |
88 | ||
89 | c) IP analysis stage. All interprocedural passes do their | |
90 | analysis. | |
91 | ||
92 | Interprocedural passes differ from small interprocedural | |
93 | passes by their ability to operate across whole program | |
94 | at linktime. Their analysis stage is performed early to | |
95 | both reduce linking times and linktime memory usage by | |
96 | not having to represent whole program in memory. | |
97 | ||
98 | d) LTO sreaming. When doing LTO, everything important gets | |
99 | streamed into the object file. | |
100 | ||
101 | Compile time and or linktime analysis stage (WPA): | |
102 | ||
103 | At linktime units gets streamed back and symbol table is | |
104 | merged. Function bodies are not streamed in and not | |
105 | available. | |
106 | e) IP propagation stage. All IP passes execute their | |
107 | IP propagation. This is done based on the earlier analysis | |
108 | without having function bodies at hand. | |
109 | f) Ltrans streaming. When doing WHOPR LTO, the program | |
110 | is partitioned and streamed into multple object files. | |
111 | ||
112 | Compile time and/or parallel linktime stage (ltrans) | |
113 | ||
114 | Each of the object files is streamed back and compiled | |
115 | separately. Now the function bodies becomes available | |
116 | again. | |
117 | ||
118 | 2) Virtual clone materialization | |
119 | (cgraph_materialize_clone) | |
120 | ||
121 | IP passes can produce copies of existing functoins (such | |
122 | as versioned clones or inline clones) without actually | |
123 | manipulating their bodies by creating virtual clones in | |
124 | the callgraph. At this time the virtual clones are | |
125 | turned into real functions | |
126 | 3) IP transformation | |
127 | ||
128 | All IP passes transform function bodies based on earlier | |
129 | decision of the IP propagation. | |
130 | ||
131 | 4) late small IP passes | |
132 | ||
133 | Simple IP passes working within single program partition. | |
134 | ||
135 | 5) Expansion | |
136 | (expand_all_functions) | |
137 | ||
138 | At this stage functions that needs to be output into | |
139 | assembler are identified and compiled in topological order | |
140 | 6) Output of variables and aliases | |
141 | Now it is known what variable references was not optimized | |
142 | out and thus all variables are output to the file. | |
143 | ||
144 | Note that with -fno-toplevel-reorder passes 5 and 6 | |
145 | are combined together in cgraph_output_in_order. | |
146 | ||
147 | Finally there are functions to manipulate the callgraph from | |
148 | backend. | |
149 | - cgraph_add_new_function is used to add backend produced | |
150 | functions introduced after the unit is finalized. | |
151 | The functions are enqueue for later processing and inserted | |
152 | into callgraph with cgraph_process_new_functions. | |
153 | ||
154 | - cgraph_function_versioning | |
155 | ||
156 | produces a copy of function into new one (a version) | |
157 | and apply simple transformations | |
158 | */ | |
159 | ||
160 | #include "config.h" | |
161 | #include "system.h" | |
162 | #include "coretypes.h" | |
163 | #include "tm.h" | |
164 | #include "tree.h" | |
165 | #include "varasm.h" | |
166 | #include "stor-layout.h" | |
167 | #include "stringpool.h" | |
168 | #include "output.h" | |
169 | #include "rtl.h" | |
170 | #include "basic-block.h" | |
171 | #include "tree-ssa-alias.h" | |
172 | #include "internal-fn.h" | |
173 | #include "gimple-fold.h" | |
174 | #include "gimple-expr.h" | |
175 | #include "is-a.h" | |
176 | #include "gimple.h" | |
177 | #include "gimplify.h" | |
178 | #include "gimple-iterator.h" | |
179 | #include "gimplify-me.h" | |
180 | #include "gimple-ssa.h" | |
181 | #include "tree-cfg.h" | |
182 | #include "tree-into-ssa.h" | |
183 | #include "tree-ssa.h" | |
184 | #include "tree-inline.h" | |
185 | #include "langhooks.h" | |
186 | #include "toplev.h" | |
187 | #include "flags.h" | |
188 | #include "debug.h" | |
189 | #include "target.h" | |
190 | #include "diagnostic.h" | |
191 | #include "params.h" | |
192 | #include "fibheap.h" | |
193 | #include "intl.h" | |
194 | #include "function.h" | |
195 | #include "ipa-prop.h" | |
196 | #include "tree-iterator.h" | |
197 | #include "tree-pass.h" | |
198 | #include "tree-dump.h" | |
199 | #include "gimple-pretty-print.h" | |
200 | #include "output.h" | |
201 | #include "coverage.h" | |
202 | #include "plugin.h" | |
203 | #include "ipa-inline.h" | |
204 | #include "ipa-utils.h" | |
205 | #include "lto-streamer.h" | |
206 | #include "except.h" | |
207 | #include "cfgloop.h" | |
208 | #include "regset.h" /* FIXME: For reg_obstack. */ | |
209 | #include "context.h" | |
210 | #include "pass_manager.h" | |
211 | #include "tree-nested.h" | |
212 | #include "gimplify.h" | |
213 | #include "dbgcnt.h" | |
214 | ||
215 | /* Queue of cgraph nodes scheduled to be added into cgraph. This is a | |
216 | secondary queue used during optimization to accommodate passes that | |
217 | may generate new functions that need to be optimized and expanded. */ | |
218 | cgraph_node_set cgraph_new_nodes; | |
219 | ||
220 | static void expand_all_functions (void); | |
221 | static void mark_functions_to_output (void); | |
222 | static void expand_function (struct cgraph_node *); | |
223 | static void handle_alias_pairs (void); | |
224 | ||
225 | FILE *cgraph_dump_file; | |
226 | ||
227 | /* Linked list of cgraph asm nodes. */ | |
228 | struct asm_node *asm_nodes; | |
229 | ||
230 | /* Last node in cgraph_asm_nodes. */ | |
231 | static GTY(()) struct asm_node *asm_last_node; | |
232 | ||
233 | /* Used for vtable lookup in thunk adjusting. */ | |
234 | static GTY (()) tree vtable_entry_type; | |
235 | ||
236 | /* Determine if symbol DECL is needed. That is, visible to something | |
237 | either outside this translation unit, something magic in the system | |
238 | configury */ | |
239 | bool | |
240 | decide_is_symbol_needed (symtab_node *node) | |
241 | { | |
242 | tree decl = node->decl; | |
243 | ||
244 | /* Double check that no one output the function into assembly file | |
245 | early. */ | |
246 | gcc_checking_assert (!DECL_ASSEMBLER_NAME_SET_P (decl) | |
247 | || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))); | |
248 | ||
249 | if (!node->definition) | |
250 | return false; | |
251 | ||
252 | if (DECL_EXTERNAL (decl)) | |
253 | return false; | |
254 | ||
255 | /* If the user told us it is used, then it must be so. */ | |
256 | if (node->force_output) | |
257 | return true; | |
258 | ||
259 | /* ABI forced symbols are needed when they are external. */ | |
260 | if (node->forced_by_abi && TREE_PUBLIC (decl)) | |
261 | return true; | |
262 | ||
263 | /* Keep constructors, destructors and virtual functions. */ | |
264 | if (TREE_CODE (decl) == FUNCTION_DECL | |
265 | && (DECL_STATIC_CONSTRUCTOR (decl) || DECL_STATIC_DESTRUCTOR (decl))) | |
266 | return true; | |
267 | ||
268 | /* Externally visible variables must be output. The exception is | |
269 | COMDAT variables that must be output only when they are needed. */ | |
270 | if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) | |
271 | return true; | |
272 | ||
273 | return false; | |
274 | } | |
275 | ||
276 | /* Head and terminator of the queue of nodes to be processed while building | |
277 | callgraph. */ | |
278 | ||
279 | static symtab_node symtab_terminator; | |
280 | static symtab_node *queued_nodes = &symtab_terminator; | |
281 | ||
282 | /* Add NODE to queue starting at QUEUED_NODES. | |
283 | The queue is linked via AUX pointers and terminated by pointer to 1. */ | |
284 | ||
285 | static void | |
286 | enqueue_node (symtab_node *node) | |
287 | { | |
288 | if (node->aux) | |
289 | return; | |
290 | gcc_checking_assert (queued_nodes); | |
291 | node->aux = queued_nodes; | |
292 | queued_nodes = node; | |
293 | } | |
294 | ||
295 | /* Process CGRAPH_NEW_FUNCTIONS and perform actions necessary to add these | |
296 | functions into callgraph in a way so they look like ordinary reachable | |
297 | functions inserted into callgraph already at construction time. */ | |
298 | ||
299 | void | |
300 | cgraph_process_new_functions (void) | |
301 | { | |
302 | tree fndecl; | |
303 | struct cgraph_node *node; | |
304 | cgraph_node_set_iterator csi; | |
305 | ||
306 | if (!cgraph_new_nodes) | |
307 | return; | |
308 | handle_alias_pairs (); | |
309 | /* Note that this queue may grow as its being processed, as the new | |
310 | functions may generate new ones. */ | |
311 | for (csi = csi_start (cgraph_new_nodes); !csi_end_p (csi); csi_next (&csi)) | |
312 | { | |
313 | node = csi_node (csi); | |
314 | fndecl = node->decl; | |
315 | switch (cgraph_state) | |
316 | { | |
317 | case CGRAPH_STATE_CONSTRUCTION: | |
318 | /* At construction time we just need to finalize function and move | |
319 | it into reachable functions list. */ | |
320 | ||
321 | cgraph_finalize_function (fndecl, false); | |
322 | node->call_function_insertion_hooks (); | |
323 | enqueue_node (node); | |
324 | break; | |
325 | ||
326 | case CGRAPH_STATE_IPA: | |
327 | case CGRAPH_STATE_IPA_SSA: | |
328 | /* When IPA optimization already started, do all essential | |
329 | transformations that has been already performed on the whole | |
330 | cgraph but not on this function. */ | |
331 | ||
332 | gimple_register_cfg_hooks (); | |
333 | if (!node->analyzed) | |
334 | node->analyze (); | |
335 | push_cfun (DECL_STRUCT_FUNCTION (fndecl)); | |
336 | if (cgraph_state == CGRAPH_STATE_IPA_SSA | |
337 | && !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (fndecl))) | |
338 | g->get_passes ()->execute_early_local_passes (); | |
339 | else if (inline_summary_vec != NULL) | |
340 | compute_inline_parameters (node, true); | |
341 | free_dominance_info (CDI_POST_DOMINATORS); | |
342 | free_dominance_info (CDI_DOMINATORS); | |
343 | pop_cfun (); | |
344 | node->call_function_insertion_hooks (); | |
345 | break; | |
346 | ||
347 | case CGRAPH_STATE_EXPANSION: | |
348 | /* Functions created during expansion shall be compiled | |
349 | directly. */ | |
350 | node->process = 0; | |
351 | node->call_function_insertion_hooks (); | |
352 | expand_function (node); | |
353 | break; | |
354 | ||
355 | default: | |
356 | gcc_unreachable (); | |
357 | break; | |
358 | } | |
359 | } | |
360 | free_cgraph_node_set (cgraph_new_nodes); | |
361 | cgraph_new_nodes = NULL; | |
362 | } | |
363 | ||
364 | /* As an GCC extension we allow redefinition of the function. The | |
365 | semantics when both copies of bodies differ is not well defined. | |
366 | We replace the old body with new body so in unit at a time mode | |
367 | we always use new body, while in normal mode we may end up with | |
368 | old body inlined into some functions and new body expanded and | |
369 | inlined in others. | |
370 | ||
371 | ??? It may make more sense to use one body for inlining and other | |
372 | body for expanding the function but this is difficult to do. */ | |
373 | ||
374 | void | |
375 | cgraph_node::reset (void) | |
376 | { | |
377 | /* If process is set, then we have already begun whole-unit analysis. | |
378 | This is *not* testing for whether we've already emitted the function. | |
379 | That case can be sort-of legitimately seen with real function redefinition | |
380 | errors. I would argue that the front end should never present us with | |
381 | such a case, but don't enforce that for now. */ | |
382 | gcc_assert (!process); | |
383 | ||
384 | /* Reset our data structures so we can analyze the function again. */ | |
385 | memset (&local, 0, sizeof (local)); | |
386 | memset (&global, 0, sizeof (global)); | |
387 | memset (&rtl, 0, sizeof (rtl)); | |
388 | analyzed = false; | |
389 | definition = false; | |
390 | alias = false; | |
391 | weakref = false; | |
392 | cpp_implicit_alias = false; | |
393 | ||
394 | remove_callees (); | |
395 | remove_all_references (); | |
396 | } | |
397 | ||
398 | /* Return true when there are references to NODE. */ | |
399 | ||
400 | static bool | |
401 | referred_to_p (symtab_node *node) | |
402 | { | |
403 | struct ipa_ref *ref = NULL; | |
404 | ||
405 | /* See if there are any references at all. */ | |
406 | if (node->iterate_referring (0, ref)) | |
407 | return true; | |
408 | /* For functions check also calls. */ | |
409 | cgraph_node *cn = dyn_cast <cgraph_node *> (node); | |
410 | if (cn && cn->callers) | |
411 | return true; | |
412 | return false; | |
413 | } | |
414 | ||
415 | /* DECL has been parsed. Take it, queue it, compile it at the whim of the | |
416 | logic in effect. If NO_COLLECT is true, then our caller cannot stand to have | |
417 | the garbage collector run at the moment. We would need to either create | |
418 | a new GC context, or just not compile right now. */ | |
419 | ||
420 | void | |
421 | cgraph_finalize_function (tree decl, bool no_collect) | |
422 | { | |
423 | struct cgraph_node *node = cgraph_node::get_create (decl); | |
424 | ||
425 | if (node->definition) | |
426 | { | |
427 | /* Nested functions should only be defined once. */ | |
428 | gcc_assert (!DECL_CONTEXT (decl) | |
429 | || TREE_CODE (DECL_CONTEXT (decl)) != FUNCTION_DECL); | |
430 | node->reset (); | |
431 | node->local.redefined_extern_inline = true; | |
432 | } | |
433 | ||
434 | notice_global_symbol (decl); | |
435 | node->definition = true; | |
436 | node->lowered = DECL_STRUCT_FUNCTION (decl)->cfg != NULL; | |
437 | ||
438 | /* With -fkeep-inline-functions we are keeping all inline functions except | |
439 | for extern inline ones. */ | |
440 | if (flag_keep_inline_functions | |
441 | && DECL_DECLARED_INLINE_P (decl) | |
442 | && !DECL_EXTERNAL (decl) | |
443 | && !DECL_DISREGARD_INLINE_LIMITS (decl)) | |
444 | node->force_output = 1; | |
445 | ||
446 | /* When not optimizing, also output the static functions. (see | |
447 | PR24561), but don't do so for always_inline functions, functions | |
448 | declared inline and nested functions. These were optimized out | |
449 | in the original implementation and it is unclear whether we want | |
450 | to change the behavior here. */ | |
451 | if ((!optimize | |
452 | && !node->cpp_implicit_alias | |
453 | && !DECL_DISREGARD_INLINE_LIMITS (decl) | |
454 | && !DECL_DECLARED_INLINE_P (decl) | |
455 | && !(DECL_CONTEXT (decl) | |
456 | && TREE_CODE (DECL_CONTEXT (decl)) == FUNCTION_DECL)) | |
457 | && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl)) | |
458 | node->force_output = 1; | |
459 | ||
460 | /* If we've not yet emitted decl, tell the debug info about it. */ | |
461 | if (!TREE_ASM_WRITTEN (decl)) | |
462 | (*debug_hooks->deferred_inline_function) (decl); | |
463 | ||
464 | /* Possibly warn about unused parameters. */ | |
465 | if (warn_unused_parameter) | |
466 | do_warn_unused_parameter (decl); | |
467 | ||
468 | if (!no_collect) | |
469 | ggc_collect (); | |
470 | ||
471 | if (cgraph_state == CGRAPH_STATE_CONSTRUCTION | |
472 | && (decide_is_symbol_needed (node) | |
473 | || referred_to_p (node))) | |
474 | enqueue_node (node); | |
475 | } | |
476 | ||
477 | /* Add the function FNDECL to the call graph. | |
478 | Unlike cgraph_finalize_function, this function is intended to be used | |
479 | by middle end and allows insertion of new function at arbitrary point | |
480 | of compilation. The function can be either in high, low or SSA form | |
481 | GIMPLE. | |
482 | ||
483 | The function is assumed to be reachable and have address taken (so no | |
484 | API breaking optimizations are performed on it). | |
485 | ||
486 | Main work done by this function is to enqueue the function for later | |
487 | processing to avoid need the passes to be re-entrant. */ | |
488 | ||
489 | void | |
490 | cgraph_node::add_new_function (tree fndecl, bool lowered) | |
491 | { | |
492 | gcc::pass_manager *passes = g->get_passes (); | |
493 | struct cgraph_node *node; | |
494 | switch (cgraph_state) | |
495 | { | |
496 | case CGRAPH_STATE_PARSING: | |
497 | cgraph_finalize_function (fndecl, false); | |
498 | break; | |
499 | case CGRAPH_STATE_CONSTRUCTION: | |
500 | /* Just enqueue function to be processed at nearest occurrence. */ | |
501 | node = cgraph_node::get_create (fndecl); | |
502 | if (lowered) | |
503 | node->lowered = true; | |
504 | if (!cgraph_new_nodes) | |
505 | cgraph_new_nodes = cgraph_node_set_new (); | |
506 | cgraph_node_set_add (cgraph_new_nodes, node); | |
507 | break; | |
508 | ||
509 | case CGRAPH_STATE_IPA: | |
510 | case CGRAPH_STATE_IPA_SSA: | |
511 | case CGRAPH_STATE_EXPANSION: | |
512 | /* Bring the function into finalized state and enqueue for later | |
513 | analyzing and compilation. */ | |
514 | node = cgraph_node::get_create (fndecl); | |
515 | node->local.local = false; | |
516 | node->definition = true; | |
517 | node->force_output = true; | |
518 | if (!lowered && cgraph_state == CGRAPH_STATE_EXPANSION) | |
519 | { | |
520 | push_cfun (DECL_STRUCT_FUNCTION (fndecl)); | |
521 | gimple_register_cfg_hooks (); | |
522 | bitmap_obstack_initialize (NULL); | |
523 | execute_pass_list (cfun, passes->all_lowering_passes); | |
524 | passes->execute_early_local_passes (); | |
525 | bitmap_obstack_release (NULL); | |
526 | pop_cfun (); | |
527 | ||
528 | lowered = true; | |
529 | } | |
530 | if (lowered) | |
531 | node->lowered = true; | |
532 | if (!cgraph_new_nodes) | |
533 | cgraph_new_nodes = cgraph_node_set_new (); | |
534 | cgraph_node_set_add (cgraph_new_nodes, node); | |
535 | break; | |
536 | ||
537 | case CGRAPH_STATE_FINISHED: | |
538 | /* At the very end of compilation we have to do all the work up | |
539 | to expansion. */ | |
540 | node = cgraph_node::create (fndecl); | |
541 | if (lowered) | |
542 | node->lowered = true; | |
543 | node->definition = true; | |
544 | node->analyze (); | |
545 | push_cfun (DECL_STRUCT_FUNCTION (fndecl)); | |
546 | gimple_register_cfg_hooks (); | |
547 | bitmap_obstack_initialize (NULL); | |
548 | if (!gimple_in_ssa_p (DECL_STRUCT_FUNCTION (fndecl))) | |
549 | g->get_passes ()->execute_early_local_passes (); | |
550 | bitmap_obstack_release (NULL); | |
551 | pop_cfun (); | |
552 | expand_function (node); | |
553 | break; | |
554 | ||
555 | default: | |
556 | gcc_unreachable (); | |
557 | } | |
558 | ||
559 | /* Set a personality if required and we already passed EH lowering. */ | |
560 | if (lowered | |
561 | && (function_needs_eh_personality (DECL_STRUCT_FUNCTION (fndecl)) | |
562 | == eh_personality_lang)) | |
563 | DECL_FUNCTION_PERSONALITY (fndecl) = lang_hooks.eh_personality (); | |
564 | } | |
565 | ||
566 | /* Add a top-level asm statement to the list. */ | |
567 | ||
568 | struct asm_node * | |
569 | add_asm_node (tree asm_str) | |
570 | { | |
571 | struct asm_node *node; | |
572 | ||
573 | node = ggc_cleared_alloc<asm_node> (); | |
574 | node->asm_str = asm_str; | |
575 | node->order = symtab_order++; | |
576 | node->next = NULL; | |
577 | if (asm_nodes == NULL) | |
578 | asm_nodes = node; | |
579 | else | |
580 | asm_last_node->next = node; | |
581 | asm_last_node = node; | |
582 | return node; | |
583 | } | |
584 | ||
585 | /* Output all asm statements we have stored up to be output. */ | |
586 | ||
587 | static void | |
588 | output_asm_statements (void) | |
589 | { | |
590 | struct asm_node *can; | |
591 | ||
592 | if (seen_error ()) | |
593 | return; | |
594 | ||
595 | for (can = asm_nodes; can; can = can->next) | |
596 | assemble_asm (can->asm_str); | |
597 | asm_nodes = NULL; | |
598 | } | |
599 | ||
600 | /* Analyze the function scheduled to be output. */ | |
601 | void | |
602 | cgraph_node::analyze (void) | |
603 | { | |
604 | tree decl = this->decl; | |
605 | location_t saved_loc = input_location; | |
606 | input_location = DECL_SOURCE_LOCATION (decl); | |
607 | ||
608 | if (thunk.thunk_p) | |
609 | { | |
610 | create_edge (cgraph_node::get (thunk.alias), | |
611 | NULL, 0, CGRAPH_FREQ_BASE); | |
612 | if (!expand_thunk (false, false)) | |
613 | { | |
614 | thunk.alias = NULL; | |
615 | analyzed = true; | |
616 | return; | |
617 | } | |
618 | thunk.alias = NULL; | |
619 | } | |
620 | if (alias) | |
621 | resolve_alias (cgraph_node::get (alias_target)); | |
622 | else if (dispatcher_function) | |
623 | { | |
624 | /* Generate the dispatcher body of multi-versioned functions. */ | |
625 | struct cgraph_function_version_info *dispatcher_version_info | |
626 | = function_version (); | |
627 | if (dispatcher_version_info != NULL | |
628 | && (dispatcher_version_info->dispatcher_resolver | |
629 | == NULL_TREE)) | |
630 | { | |
631 | tree resolver = NULL_TREE; | |
632 | gcc_assert (targetm.generate_version_dispatcher_body); | |
633 | resolver = targetm.generate_version_dispatcher_body (this); | |
634 | gcc_assert (resolver != NULL_TREE); | |
635 | } | |
636 | } | |
637 | else | |
638 | { | |
639 | push_cfun (DECL_STRUCT_FUNCTION (decl)); | |
640 | ||
641 | assign_assembler_name_if_neeeded (decl); | |
642 | ||
643 | /* Make sure to gimplify bodies only once. During analyzing a | |
644 | function we lower it, which will require gimplified nested | |
645 | functions, so we can end up here with an already gimplified | |
646 | body. */ | |
647 | if (!gimple_has_body_p (decl)) | |
648 | gimplify_function_tree (decl); | |
649 | dump_function (TDI_generic, decl); | |
650 | ||
651 | /* Lower the function. */ | |
652 | if (!lowered) | |
653 | { | |
654 | if (nested) | |
655 | lower_nested_functions (decl); | |
656 | gcc_assert (!nested); | |
657 | ||
658 | gimple_register_cfg_hooks (); | |
659 | bitmap_obstack_initialize (NULL); | |
660 | execute_pass_list (cfun, g->get_passes ()->all_lowering_passes); | |
661 | free_dominance_info (CDI_POST_DOMINATORS); | |
662 | free_dominance_info (CDI_DOMINATORS); | |
663 | compact_blocks (); | |
664 | bitmap_obstack_release (NULL); | |
665 | lowered = true; | |
666 | } | |
667 | ||
668 | pop_cfun (); | |
669 | } | |
670 | analyzed = true; | |
671 | ||
672 | input_location = saved_loc; | |
673 | } | |
674 | ||
675 | /* C++ frontend produce same body aliases all over the place, even before PCH | |
676 | gets streamed out. It relies on us linking the aliases with their function | |
677 | in order to do the fixups, but ipa-ref is not PCH safe. Consequentely we | |
678 | first produce aliases without links, but once C++ FE is sure he won't sream | |
679 | PCH we build the links via this function. */ | |
680 | ||
681 | void | |
682 | cgraph_process_same_body_aliases (void) | |
683 | { | |
684 | symtab_node *node; | |
685 | FOR_EACH_SYMBOL (node) | |
686 | if (node->cpp_implicit_alias && !node->analyzed) | |
687 | node->resolve_alias | |
688 | (TREE_CODE (node->alias_target) == VAR_DECL | |
689 | ? (symtab_node *)varpool_node::get_create (node->alias_target) | |
690 | : (symtab_node *)cgraph_node::get_create (node->alias_target)); | |
691 | cpp_implicit_aliases_done = true; | |
692 | } | |
693 | ||
694 | /* Process attributes common for vars and functions. */ | |
695 | ||
696 | static void | |
697 | process_common_attributes (tree decl) | |
698 | { | |
699 | tree weakref = lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)); | |
700 | ||
701 | if (weakref && !lookup_attribute ("alias", DECL_ATTRIBUTES (decl))) | |
702 | { | |
703 | warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wattributes, | |
704 | "%<weakref%> attribute should be accompanied with" | |
705 | " an %<alias%> attribute"); | |
706 | DECL_WEAK (decl) = 0; | |
707 | DECL_ATTRIBUTES (decl) = remove_attribute ("weakref", | |
708 | DECL_ATTRIBUTES (decl)); | |
709 | } | |
710 | } | |
711 | ||
712 | /* Look for externally_visible and used attributes and mark cgraph nodes | |
713 | accordingly. | |
714 | ||
715 | We cannot mark the nodes at the point the attributes are processed (in | |
716 | handle_*_attribute) because the copy of the declarations available at that | |
717 | point may not be canonical. For example, in: | |
718 | ||
719 | void f(); | |
720 | void f() __attribute__((used)); | |
721 | ||
722 | the declaration we see in handle_used_attribute will be the second | |
723 | declaration -- but the front end will subsequently merge that declaration | |
724 | with the original declaration and discard the second declaration. | |
725 | ||
726 | Furthermore, we can't mark these nodes in cgraph_finalize_function because: | |
727 | ||
728 | void f() {} | |
729 | void f() __attribute__((externally_visible)); | |
730 | ||
731 | is valid. | |
732 | ||
733 | So, we walk the nodes at the end of the translation unit, applying the | |
734 | attributes at that point. */ | |
735 | ||
736 | static void | |
737 | process_function_and_variable_attributes (struct cgraph_node *first, | |
738 | varpool_node *first_var) | |
739 | { | |
740 | struct cgraph_node *node; | |
741 | varpool_node *vnode; | |
742 | ||
743 | for (node = cgraph_first_function (); node != first; | |
744 | node = cgraph_next_function (node)) | |
745 | { | |
746 | tree decl = node->decl; | |
747 | if (DECL_PRESERVE_P (decl)) | |
748 | node->mark_force_output (); | |
749 | else if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl))) | |
750 | { | |
751 | if (! TREE_PUBLIC (node->decl)) | |
752 | warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes, | |
753 | "%<externally_visible%>" | |
754 | " attribute have effect only on public objects"); | |
755 | } | |
756 | if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)) | |
757 | && (node->definition && !node->alias)) | |
758 | { | |
759 | warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes, | |
760 | "%<weakref%> attribute ignored" | |
761 | " because function is defined"); | |
762 | DECL_WEAK (decl) = 0; | |
763 | DECL_ATTRIBUTES (decl) = remove_attribute ("weakref", | |
764 | DECL_ATTRIBUTES (decl)); | |
765 | } | |
766 | ||
767 | if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (decl)) | |
768 | && !DECL_DECLARED_INLINE_P (decl) | |
769 | /* redefining extern inline function makes it DECL_UNINLINABLE. */ | |
770 | && !DECL_UNINLINABLE (decl)) | |
771 | warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wattributes, | |
772 | "always_inline function might not be inlinable"); | |
773 | ||
774 | process_common_attributes (decl); | |
775 | } | |
776 | for (vnode = varpool_first_variable (); vnode != first_var; | |
777 | vnode = varpool_next_variable (vnode)) | |
778 | { | |
779 | tree decl = vnode->decl; | |
780 | if (DECL_EXTERNAL (decl) | |
781 | && DECL_INITIAL (decl)) | |
782 | varpool_node::finalize_decl (decl); | |
783 | if (DECL_PRESERVE_P (decl)) | |
784 | vnode->force_output = true; | |
785 | else if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl))) | |
786 | { | |
787 | if (! TREE_PUBLIC (vnode->decl)) | |
788 | warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes, | |
789 | "%<externally_visible%>" | |
790 | " attribute have effect only on public objects"); | |
791 | } | |
792 | if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)) | |
793 | && vnode->definition | |
794 | && DECL_INITIAL (decl)) | |
795 | { | |
796 | warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes, | |
797 | "%<weakref%> attribute ignored" | |
798 | " because variable is initialized"); | |
799 | DECL_WEAK (decl) = 0; | |
800 | DECL_ATTRIBUTES (decl) = remove_attribute ("weakref", | |
801 | DECL_ATTRIBUTES (decl)); | |
802 | } | |
803 | process_common_attributes (decl); | |
804 | } | |
805 | } | |
806 | ||
807 | /* Mark DECL as finalized. By finalizing the declaration, frontend instruct the | |
808 | middle end to output the variable to asm file, if needed or externally | |
809 | visible. */ | |
810 | ||
811 | void | |
812 | varpool_node::finalize_decl (tree decl) | |
813 | { | |
814 | varpool_node *node = varpool_node::get_create (decl); | |
815 | ||
816 | gcc_assert (TREE_STATIC (decl) || DECL_EXTERNAL (decl)); | |
817 | ||
818 | if (node->definition) | |
819 | return; | |
820 | notice_global_symbol (decl); | |
821 | node->definition = true; | |
822 | if (TREE_THIS_VOLATILE (decl) || DECL_PRESERVE_P (decl) | |
823 | /* Traditionally we do not eliminate static variables when not | |
824 | optimizing and when not doing toplevel reoder. */ | |
825 | || (!flag_toplevel_reorder && !DECL_COMDAT (node->decl) | |
826 | && !DECL_ARTIFICIAL (node->decl))) | |
827 | node->force_output = true; | |
828 | ||
829 | if (cgraph_state == CGRAPH_STATE_CONSTRUCTION | |
830 | && (decide_is_symbol_needed (node) | |
831 | || referred_to_p (node))) | |
832 | enqueue_node (node); | |
833 | if (cgraph_state >= CGRAPH_STATE_IPA_SSA) | |
834 | node->analyze (); | |
835 | /* Some frontends produce various interface variables after compilation | |
836 | finished. */ | |
837 | if (cgraph_state == CGRAPH_STATE_FINISHED | |
838 | || (!flag_toplevel_reorder && cgraph_state == CGRAPH_STATE_EXPANSION)) | |
839 | node->assemble_decl (); | |
840 | } | |
841 | ||
842 | /* EDGE is an polymorphic call. Mark all possible targets as reachable | |
843 | and if there is only one target, perform trivial devirtualization. | |
844 | REACHABLE_CALL_TARGETS collects target lists we already walked to | |
845 | avoid udplicate work. */ | |
846 | ||
847 | static void | |
848 | walk_polymorphic_call_targets (hash_set<void *> *reachable_call_targets, | |
849 | struct cgraph_edge *edge) | |
850 | { | |
851 | unsigned int i; | |
852 | void *cache_token; | |
853 | bool final; | |
854 | vec <cgraph_node *>targets | |
855 | = possible_polymorphic_call_targets | |
856 | (edge, &final, &cache_token); | |
857 | ||
858 | if (!reachable_call_targets->add (cache_token)) | |
859 | { | |
860 | if (cgraph_dump_file) | |
861 | dump_possible_polymorphic_call_targets | |
862 | (cgraph_dump_file, edge); | |
863 | ||
864 | for (i = 0; i < targets.length (); i++) | |
865 | { | |
866 | /* Do not bother to mark virtual methods in anonymous namespace; | |
867 | either we will find use of virtual table defining it, or it is | |
868 | unused. */ | |
869 | if (targets[i]->definition | |
870 | && TREE_CODE | |
871 | (TREE_TYPE (targets[i]->decl)) | |
872 | == METHOD_TYPE | |
873 | && !type_in_anonymous_namespace_p | |
874 | (method_class_type | |
875 | (TREE_TYPE (targets[i]->decl)))) | |
876 | enqueue_node (targets[i]); | |
877 | } | |
878 | } | |
879 | ||
880 | /* Very trivial devirtualization; when the type is | |
881 | final or anonymous (so we know all its derivation) | |
882 | and there is only one possible virtual call target, | |
883 | make the edge direct. */ | |
884 | if (final) | |
885 | { | |
886 | if (targets.length () <= 1 && dbg_cnt (devirt)) | |
887 | { | |
888 | cgraph_node *target; | |
889 | if (targets.length () == 1) | |
890 | target = targets[0]; | |
891 | else | |
892 | target = cgraph_node::create | |
893 | (builtin_decl_implicit (BUILT_IN_UNREACHABLE)); | |
894 | ||
895 | if (cgraph_dump_file) | |
896 | { | |
897 | fprintf (cgraph_dump_file, | |
898 | "Devirtualizing call: "); | |
899 | print_gimple_stmt (cgraph_dump_file, | |
900 | edge->call_stmt, 0, | |
901 | TDF_SLIM); | |
902 | } | |
903 | if (dump_enabled_p ()) | |
904 | { | |
905 | location_t locus = gimple_location_safe (edge->call_stmt); | |
906 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, locus, | |
907 | "devirtualizing call in %s to %s\n", | |
908 | edge->caller->name (), target->name ()); | |
909 | } | |
910 | ||
911 | cgraph_make_edge_direct (edge, target); | |
912 | cgraph_redirect_edge_call_stmt_to_callee (edge); | |
913 | if (cgraph_dump_file) | |
914 | { | |
915 | fprintf (cgraph_dump_file, | |
916 | "Devirtualized as: "); | |
917 | print_gimple_stmt (cgraph_dump_file, | |
918 | edge->call_stmt, 0, | |
919 | TDF_SLIM); | |
920 | } | |
921 | } | |
922 | } | |
923 | } | |
924 | ||
925 | ||
926 | /* Discover all functions and variables that are trivially needed, analyze | |
927 | them as well as all functions and variables referred by them */ | |
928 | ||
929 | static void | |
930 | analyze_functions (void) | |
931 | { | |
932 | /* Keep track of already processed nodes when called multiple times for | |
933 | intermodule optimization. */ | |
934 | static struct cgraph_node *first_analyzed; | |
935 | struct cgraph_node *first_handled = first_analyzed; | |
936 | static varpool_node *first_analyzed_var; | |
937 | varpool_node *first_handled_var = first_analyzed_var; | |
938 | hash_set<void *> reachable_call_targets; | |
939 | ||
940 | symtab_node *node; | |
941 | symtab_node *next; | |
942 | int i; | |
943 | struct ipa_ref *ref; | |
944 | bool changed = true; | |
945 | location_t saved_loc = input_location; | |
946 | ||
947 | bitmap_obstack_initialize (NULL); | |
948 | cgraph_state = CGRAPH_STATE_CONSTRUCTION; | |
949 | input_location = UNKNOWN_LOCATION; | |
950 | ||
951 | /* Ugly, but the fixup can not happen at a time same body alias is created; | |
952 | C++ FE is confused about the COMDAT groups being right. */ | |
953 | if (cpp_implicit_aliases_done) | |
954 | FOR_EACH_SYMBOL (node) | |
955 | if (node->cpp_implicit_alias) | |
956 | node->fixup_same_cpp_alias_visibility (node->get_alias_target ()); | |
957 | if (optimize && flag_devirtualize) | |
958 | build_type_inheritance_graph (); | |
959 | ||
960 | /* Analysis adds static variables that in turn adds references to new functions. | |
961 | So we need to iterate the process until it stabilize. */ | |
962 | while (changed) | |
963 | { | |
964 | changed = false; | |
965 | process_function_and_variable_attributes (first_analyzed, | |
966 | first_analyzed_var); | |
967 | ||
968 | /* First identify the trivially needed symbols. */ | |
969 | for (node = symtab_nodes; | |
970 | node != first_analyzed | |
971 | && node != first_analyzed_var; node = node->next) | |
972 | { | |
973 | /* Convert COMDAT group designators to IDENTIFIER_NODEs. */ | |
974 | node->get_comdat_group_id (); | |
975 | if (decide_is_symbol_needed (node)) | |
976 | { | |
977 | enqueue_node (node); | |
978 | if (!changed && cgraph_dump_file) | |
979 | fprintf (cgraph_dump_file, "Trivially needed symbols:"); | |
980 | changed = true; | |
981 | if (cgraph_dump_file) | |
982 | fprintf (cgraph_dump_file, " %s", node->asm_name ()); | |
983 | if (!changed && cgraph_dump_file) | |
984 | fprintf (cgraph_dump_file, "\n"); | |
985 | } | |
986 | if (node == first_analyzed | |
987 | || node == first_analyzed_var) | |
988 | break; | |
989 | } | |
990 | cgraph_process_new_functions (); | |
991 | first_analyzed_var = varpool_first_variable (); | |
992 | first_analyzed = cgraph_first_function (); | |
993 | ||
994 | if (changed && cgraph_dump_file) | |
995 | fprintf (cgraph_dump_file, "\n"); | |
996 | ||
997 | /* Lower representation, build callgraph edges and references for all trivially | |
998 | needed symbols and all symbols referred by them. */ | |
999 | while (queued_nodes != &symtab_terminator) | |
1000 | { | |
1001 | changed = true; | |
1002 | node = queued_nodes; | |
1003 | queued_nodes = (symtab_node *)queued_nodes->aux; | |
1004 | cgraph_node *cnode = dyn_cast <cgraph_node *> (node); | |
1005 | if (cnode && cnode->definition) | |
1006 | { | |
1007 | struct cgraph_edge *edge; | |
1008 | tree decl = cnode->decl; | |
1009 | ||
1010 | /* ??? It is possible to create extern inline function | |
1011 | and later using weak alias attribute to kill its body. | |
1012 | See gcc.c-torture/compile/20011119-1.c */ | |
1013 | if (!DECL_STRUCT_FUNCTION (decl) | |
1014 | && !cnode->alias | |
1015 | && !cnode->thunk.thunk_p | |
1016 | && !cnode->dispatcher_function) | |
1017 | { | |
1018 | cnode->reset (); | |
1019 | cnode->local.redefined_extern_inline = true; | |
1020 | continue; | |
1021 | } | |
1022 | ||
1023 | if (!cnode->analyzed) | |
1024 | cnode->analyze (); | |
1025 | ||
1026 | for (edge = cnode->callees; edge; edge = edge->next_callee) | |
1027 | if (edge->callee->definition) | |
1028 | enqueue_node (edge->callee); | |
1029 | if (optimize && flag_devirtualize) | |
1030 | { | |
1031 | struct cgraph_edge *next; | |
1032 | ||
1033 | for (edge = cnode->indirect_calls; edge; edge = next) | |
1034 | { | |
1035 | next = edge->next_callee; | |
1036 | if (edge->indirect_info->polymorphic) | |
1037 | walk_polymorphic_call_targets (&reachable_call_targets, | |
1038 | edge); | |
1039 | } | |
1040 | } | |
1041 | ||
1042 | /* If decl is a clone of an abstract function, | |
1043 | mark that abstract function so that we don't release its body. | |
1044 | The DECL_INITIAL() of that abstract function declaration | |
1045 | will be later needed to output debug info. */ | |
1046 | if (DECL_ABSTRACT_ORIGIN (decl)) | |
1047 | { | |
1048 | struct cgraph_node *origin_node | |
1049 | = cgraph_node::get_create (DECL_ABSTRACT_ORIGIN (decl)); | |
1050 | origin_node->used_as_abstract_origin = true; | |
1051 | } | |
1052 | } | |
1053 | else | |
1054 | { | |
1055 | varpool_node *vnode = dyn_cast <varpool_node *> (node); | |
1056 | if (vnode && vnode->definition && !vnode->analyzed) | |
1057 | vnode->analyze (); | |
1058 | } | |
1059 | ||
1060 | if (node->same_comdat_group) | |
1061 | { | |
1062 | symtab_node *next; | |
1063 | for (next = node->same_comdat_group; | |
1064 | next != node; | |
1065 | next = next->same_comdat_group) | |
1066 | enqueue_node (next); | |
1067 | } | |
1068 | for (i = 0; node->iterate_reference (i, ref); i++) | |
1069 | if (ref->referred->definition) | |
1070 | enqueue_node (ref->referred); | |
1071 | cgraph_process_new_functions (); | |
1072 | } | |
1073 | } | |
1074 | if (optimize && flag_devirtualize) | |
1075 | update_type_inheritance_graph (); | |
1076 | ||
1077 | /* Collect entry points to the unit. */ | |
1078 | if (cgraph_dump_file) | |
1079 | { | |
1080 | fprintf (cgraph_dump_file, "\n\nInitial "); | |
1081 | symtab_node::dump_table (cgraph_dump_file); | |
1082 | } | |
1083 | ||
1084 | if (cgraph_dump_file) | |
1085 | fprintf (cgraph_dump_file, "\nRemoving unused symbols:"); | |
1086 | ||
1087 | for (node = symtab_nodes; | |
1088 | node != first_handled | |
1089 | && node != first_handled_var; node = next) | |
1090 | { | |
1091 | next = node->next; | |
1092 | if (!node->aux && !referred_to_p (node)) | |
1093 | { | |
1094 | if (cgraph_dump_file) | |
1095 | fprintf (cgraph_dump_file, " %s", node->name ()); | |
1096 | node->remove (); | |
1097 | continue; | |
1098 | } | |
1099 | if (cgraph_node *cnode = dyn_cast <cgraph_node *> (node)) | |
1100 | { | |
1101 | tree decl = node->decl; | |
1102 | ||
1103 | if (cnode->definition && !gimple_has_body_p (decl) | |
1104 | && !cnode->alias | |
1105 | && !cnode->thunk.thunk_p) | |
1106 | cnode->reset (); | |
1107 | ||
1108 | gcc_assert (!cnode->definition || cnode->thunk.thunk_p | |
1109 | || cnode->alias | |
1110 | || gimple_has_body_p (decl)); | |
1111 | gcc_assert (cnode->analyzed == cnode->definition); | |
1112 | } | |
1113 | node->aux = NULL; | |
1114 | } | |
1115 | for (;node; node = node->next) | |
1116 | node->aux = NULL; | |
1117 | first_analyzed = cgraph_first_function (); | |
1118 | first_analyzed_var = varpool_first_variable (); | |
1119 | if (cgraph_dump_file) | |
1120 | { | |
1121 | fprintf (cgraph_dump_file, "\n\nReclaimed "); | |
1122 | symtab_node::dump_table (cgraph_dump_file); | |
1123 | } | |
1124 | bitmap_obstack_release (NULL); | |
1125 | ggc_collect (); | |
1126 | /* Initialize assembler name hash, in particular we want to trigger C++ | |
1127 | mangling and same body alias creation before we free DECL_ARGUMENTS | |
1128 | used by it. */ | |
1129 | if (!seen_error ()) | |
1130 | symtab_initialize_asm_name_hash (); | |
1131 | ||
1132 | input_location = saved_loc; | |
1133 | } | |
1134 | ||
1135 | /* Translate the ugly representation of aliases as alias pairs into nice | |
1136 | representation in callgraph. We don't handle all cases yet, | |
1137 | unfortunately. */ | |
1138 | ||
1139 | static void | |
1140 | handle_alias_pairs (void) | |
1141 | { | |
1142 | alias_pair *p; | |
1143 | unsigned i; | |
1144 | ||
1145 | for (i = 0; alias_pairs && alias_pairs->iterate (i, &p);) | |
1146 | { | |
1147 | symtab_node *target_node = symtab_node_for_asm (p->target); | |
1148 | ||
1149 | /* Weakrefs with target not defined in current unit are easy to handle: | |
1150 | they behave just as external variables except we need to note the | |
1151 | alias flag to later output the weakref pseudo op into asm file. */ | |
1152 | if (!target_node | |
1153 | && lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)) != NULL) | |
1154 | { | |
1155 | symtab_node *node = symtab_node::get (p->decl); | |
1156 | if (node) | |
1157 | { | |
1158 | node->alias_target = p->target; | |
1159 | node->weakref = true; | |
1160 | node->alias = true; | |
1161 | } | |
1162 | alias_pairs->unordered_remove (i); | |
1163 | continue; | |
1164 | } | |
1165 | else if (!target_node) | |
1166 | { | |
1167 | error ("%q+D aliased to undefined symbol %qE", p->decl, p->target); | |
1168 | symtab_node *node = symtab_node::get (p->decl); | |
1169 | if (node) | |
1170 | node->alias = false; | |
1171 | alias_pairs->unordered_remove (i); | |
1172 | continue; | |
1173 | } | |
1174 | ||
1175 | if (DECL_EXTERNAL (target_node->decl) | |
1176 | /* We use local aliases for C++ thunks to force the tailcall | |
1177 | to bind locally. This is a hack - to keep it working do | |
1178 | the following (which is not strictly correct). */ | |
1179 | && (! TREE_CODE (target_node->decl) == FUNCTION_DECL | |
1180 | || ! DECL_VIRTUAL_P (target_node->decl)) | |
1181 | && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl))) | |
1182 | { | |
1183 | error ("%q+D aliased to external symbol %qE", | |
1184 | p->decl, p->target); | |
1185 | } | |
1186 | ||
1187 | if (TREE_CODE (p->decl) == FUNCTION_DECL | |
1188 | && target_node && is_a <cgraph_node *> (target_node)) | |
1189 | { | |
1190 | struct cgraph_node *src_node = cgraph_node::get (p->decl); | |
1191 | if (src_node && src_node->definition) | |
1192 | src_node->reset (); | |
1193 | cgraph_node::create_alias (p->decl, target_node->decl); | |
1194 | alias_pairs->unordered_remove (i); | |
1195 | } | |
1196 | else if (TREE_CODE (p->decl) == VAR_DECL | |
1197 | && target_node && is_a <varpool_node *> (target_node)) | |
1198 | { | |
1199 | varpool_node::create_alias (p->decl, target_node->decl); | |
1200 | alias_pairs->unordered_remove (i); | |
1201 | } | |
1202 | else | |
1203 | { | |
1204 | error ("%q+D alias in between function and variable is not supported", | |
1205 | p->decl); | |
1206 | warning (0, "%q+D aliased declaration", | |
1207 | target_node->decl); | |
1208 | alias_pairs->unordered_remove (i); | |
1209 | } | |
1210 | } | |
1211 | vec_free (alias_pairs); | |
1212 | } | |
1213 | ||
1214 | ||
1215 | /* Figure out what functions we want to assemble. */ | |
1216 | ||
1217 | static void | |
1218 | mark_functions_to_output (void) | |
1219 | { | |
1220 | struct cgraph_node *node; | |
1221 | #ifdef ENABLE_CHECKING | |
1222 | bool check_same_comdat_groups = false; | |
1223 | ||
1224 | FOR_EACH_FUNCTION (node) | |
1225 | gcc_assert (!node->process); | |
1226 | #endif | |
1227 | ||
1228 | FOR_EACH_FUNCTION (node) | |
1229 | { | |
1230 | tree decl = node->decl; | |
1231 | ||
1232 | gcc_assert (!node->process || node->same_comdat_group); | |
1233 | if (node->process) | |
1234 | continue; | |
1235 | ||
1236 | /* We need to output all local functions that are used and not | |
1237 | always inlined, as well as those that are reachable from | |
1238 | outside the current compilation unit. */ | |
1239 | if (node->analyzed | |
1240 | && !node->thunk.thunk_p | |
1241 | && !node->alias | |
1242 | && !node->global.inlined_to | |
1243 | && !TREE_ASM_WRITTEN (decl) | |
1244 | && !DECL_EXTERNAL (decl)) | |
1245 | { | |
1246 | node->process = 1; | |
1247 | if (node->same_comdat_group) | |
1248 | { | |
1249 | struct cgraph_node *next; | |
1250 | for (next = dyn_cast<cgraph_node *> (node->same_comdat_group); | |
1251 | next != node; | |
1252 | next = dyn_cast<cgraph_node *> (next->same_comdat_group)) | |
1253 | if (!next->thunk.thunk_p && !next->alias | |
1254 | && !next->comdat_local_p ()) | |
1255 | next->process = 1; | |
1256 | } | |
1257 | } | |
1258 | else if (node->same_comdat_group) | |
1259 | { | |
1260 | #ifdef ENABLE_CHECKING | |
1261 | check_same_comdat_groups = true; | |
1262 | #endif | |
1263 | } | |
1264 | else | |
1265 | { | |
1266 | /* We should've reclaimed all functions that are not needed. */ | |
1267 | #ifdef ENABLE_CHECKING | |
1268 | if (!node->global.inlined_to | |
1269 | && gimple_has_body_p (decl) | |
1270 | /* FIXME: in ltrans unit when offline copy is outside partition but inline copies | |
1271 | are inside partition, we can end up not removing the body since we no longer | |
1272 | have analyzed node pointing to it. */ | |
1273 | && !node->in_other_partition | |
1274 | && !node->alias | |
1275 | && !node->clones | |
1276 | && !DECL_EXTERNAL (decl)) | |
1277 | { | |
1278 | node->debug (); | |
1279 | internal_error ("failed to reclaim unneeded function"); | |
1280 | } | |
1281 | #endif | |
1282 | gcc_assert (node->global.inlined_to | |
1283 | || !gimple_has_body_p (decl) | |
1284 | || node->in_other_partition | |
1285 | || node->clones | |
1286 | || DECL_ARTIFICIAL (decl) | |
1287 | || DECL_EXTERNAL (decl)); | |
1288 | ||
1289 | } | |
1290 | ||
1291 | } | |
1292 | #ifdef ENABLE_CHECKING | |
1293 | if (check_same_comdat_groups) | |
1294 | FOR_EACH_FUNCTION (node) | |
1295 | if (node->same_comdat_group && !node->process) | |
1296 | { | |
1297 | tree decl = node->decl; | |
1298 | if (!node->global.inlined_to | |
1299 | && gimple_has_body_p (decl) | |
1300 | /* FIXME: in an ltrans unit when the offline copy is outside a | |
1301 | partition but inline copies are inside a partition, we can | |
1302 | end up not removing the body since we no longer have an | |
1303 | analyzed node pointing to it. */ | |
1304 | && !node->in_other_partition | |
1305 | && !node->clones | |
1306 | && !DECL_EXTERNAL (decl)) | |
1307 | { | |
1308 | node->debug (); | |
1309 | internal_error ("failed to reclaim unneeded function in same " | |
1310 | "comdat group"); | |
1311 | } | |
1312 | } | |
1313 | #endif | |
1314 | } | |
1315 | ||
1316 | /* DECL is FUNCTION_DECL. Initialize datastructures so DECL is a function | |
1317 | in lowered gimple form. IN_SSA is true if the gimple is in SSA. | |
1318 | ||
1319 | Set current_function_decl and cfun to newly constructed empty function body. | |
1320 | return basic block in the function body. */ | |
1321 | ||
1322 | basic_block | |
1323 | init_lowered_empty_function (tree decl, bool in_ssa) | |
1324 | { | |
1325 | basic_block bb; | |
1326 | ||
1327 | current_function_decl = decl; | |
1328 | allocate_struct_function (decl, false); | |
1329 | gimple_register_cfg_hooks (); | |
1330 | init_empty_tree_cfg (); | |
1331 | ||
1332 | if (in_ssa) | |
1333 | { | |
1334 | init_tree_ssa (cfun); | |
1335 | init_ssa_operands (cfun); | |
1336 | cfun->gimple_df->in_ssa_p = true; | |
1337 | cfun->curr_properties |= PROP_ssa; | |
1338 | } | |
1339 | ||
1340 | DECL_INITIAL (decl) = make_node (BLOCK); | |
1341 | ||
1342 | DECL_SAVED_TREE (decl) = error_mark_node; | |
1343 | cfun->curr_properties |= (PROP_gimple_lcf | PROP_gimple_leh | PROP_gimple_any | |
1344 | | PROP_cfg | PROP_loops); | |
1345 | ||
1346 | set_loops_for_fn (cfun, ggc_cleared_alloc<loops> ()); | |
1347 | init_loops_structure (cfun, loops_for_fn (cfun), 1); | |
1348 | loops_for_fn (cfun)->state |= LOOPS_MAY_HAVE_MULTIPLE_LATCHES; | |
1349 | ||
1350 | /* Create BB for body of the function and connect it properly. */ | |
1351 | bb = create_basic_block (NULL, (void *) 0, ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
1352 | make_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb, EDGE_FALLTHRU); | |
1353 | make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0); | |
1354 | add_bb_to_loop (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun)->loop_father); | |
1355 | ||
1356 | return bb; | |
1357 | } | |
1358 | ||
1359 | /* Adjust PTR by the constant FIXED_OFFSET, and by the vtable | |
1360 | offset indicated by VIRTUAL_OFFSET, if that is | |
1361 | non-null. THIS_ADJUSTING is nonzero for a this adjusting thunk and | |
1362 | zero for a result adjusting thunk. */ | |
1363 | ||
1364 | static tree | |
1365 | thunk_adjust (gimple_stmt_iterator * bsi, | |
1366 | tree ptr, bool this_adjusting, | |
1367 | HOST_WIDE_INT fixed_offset, tree virtual_offset) | |
1368 | { | |
1369 | gimple stmt; | |
1370 | tree ret; | |
1371 | ||
1372 | if (this_adjusting | |
1373 | && fixed_offset != 0) | |
1374 | { | |
1375 | stmt = gimple_build_assign | |
1376 | (ptr, fold_build_pointer_plus_hwi_loc (input_location, | |
1377 | ptr, | |
1378 | fixed_offset)); | |
1379 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1380 | } | |
1381 | ||
1382 | /* If there's a virtual offset, look up that value in the vtable and | |
1383 | adjust the pointer again. */ | |
1384 | if (virtual_offset) | |
1385 | { | |
1386 | tree vtabletmp; | |
1387 | tree vtabletmp2; | |
1388 | tree vtabletmp3; | |
1389 | ||
1390 | if (!vtable_entry_type) | |
1391 | { | |
1392 | tree vfunc_type = make_node (FUNCTION_TYPE); | |
1393 | TREE_TYPE (vfunc_type) = integer_type_node; | |
1394 | TYPE_ARG_TYPES (vfunc_type) = NULL_TREE; | |
1395 | layout_type (vfunc_type); | |
1396 | ||
1397 | vtable_entry_type = build_pointer_type (vfunc_type); | |
1398 | } | |
1399 | ||
1400 | vtabletmp = | |
1401 | create_tmp_reg (build_pointer_type | |
1402 | (build_pointer_type (vtable_entry_type)), "vptr"); | |
1403 | ||
1404 | /* The vptr is always at offset zero in the object. */ | |
1405 | stmt = gimple_build_assign (vtabletmp, | |
1406 | build1 (NOP_EXPR, TREE_TYPE (vtabletmp), | |
1407 | ptr)); | |
1408 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1409 | ||
1410 | /* Form the vtable address. */ | |
1411 | vtabletmp2 = create_tmp_reg (TREE_TYPE (TREE_TYPE (vtabletmp)), | |
1412 | "vtableaddr"); | |
1413 | stmt = gimple_build_assign (vtabletmp2, | |
1414 | build_simple_mem_ref (vtabletmp)); | |
1415 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1416 | ||
1417 | /* Find the entry with the vcall offset. */ | |
1418 | stmt = gimple_build_assign (vtabletmp2, | |
1419 | fold_build_pointer_plus_loc (input_location, | |
1420 | vtabletmp2, | |
1421 | virtual_offset)); | |
1422 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1423 | ||
1424 | /* Get the offset itself. */ | |
1425 | vtabletmp3 = create_tmp_reg (TREE_TYPE (TREE_TYPE (vtabletmp2)), | |
1426 | "vcalloffset"); | |
1427 | stmt = gimple_build_assign (vtabletmp3, | |
1428 | build_simple_mem_ref (vtabletmp2)); | |
1429 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1430 | ||
1431 | /* Adjust the `this' pointer. */ | |
1432 | ptr = fold_build_pointer_plus_loc (input_location, ptr, vtabletmp3); | |
1433 | ptr = force_gimple_operand_gsi (bsi, ptr, true, NULL_TREE, false, | |
1434 | GSI_CONTINUE_LINKING); | |
1435 | } | |
1436 | ||
1437 | if (!this_adjusting | |
1438 | && fixed_offset != 0) | |
1439 | /* Adjust the pointer by the constant. */ | |
1440 | { | |
1441 | tree ptrtmp; | |
1442 | ||
1443 | if (TREE_CODE (ptr) == VAR_DECL) | |
1444 | ptrtmp = ptr; | |
1445 | else | |
1446 | { | |
1447 | ptrtmp = create_tmp_reg (TREE_TYPE (ptr), "ptr"); | |
1448 | stmt = gimple_build_assign (ptrtmp, ptr); | |
1449 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1450 | } | |
1451 | ptr = fold_build_pointer_plus_hwi_loc (input_location, | |
1452 | ptrtmp, fixed_offset); | |
1453 | } | |
1454 | ||
1455 | /* Emit the statement and gimplify the adjustment expression. */ | |
1456 | ret = create_tmp_reg (TREE_TYPE (ptr), "adjusted_this"); | |
1457 | stmt = gimple_build_assign (ret, ptr); | |
1458 | gsi_insert_after (bsi, stmt, GSI_NEW_STMT); | |
1459 | ||
1460 | return ret; | |
1461 | } | |
1462 | ||
1463 | /* Expand thunk NODE to gimple if possible. | |
1464 | When FORCE_GIMPLE_THUNK is true, gimple thunk is created and | |
1465 | no assembler is produced. | |
1466 | When OUTPUT_ASM_THUNK is true, also produce assembler for | |
1467 | thunks that are not lowered. */ | |
1468 | ||
1469 | bool | |
1470 | cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) | |
1471 | { | |
1472 | bool this_adjusting = thunk.this_adjusting; | |
1473 | HOST_WIDE_INT fixed_offset = thunk.fixed_offset; | |
1474 | HOST_WIDE_INT virtual_value = thunk.virtual_value; | |
1475 | tree virtual_offset = NULL; | |
1476 | tree alias = callees->callee->decl; | |
1477 | tree thunk_fndecl = decl; | |
1478 | tree a; | |
1479 | ||
1480 | ||
1481 | if (!force_gimple_thunk && this_adjusting | |
1482 | && targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset, | |
1483 | virtual_value, alias)) | |
1484 | { | |
1485 | const char *fnname; | |
1486 | tree fn_block; | |
1487 | tree restype = TREE_TYPE (TREE_TYPE (thunk_fndecl)); | |
1488 | ||
1489 | if (!output_asm_thunks) | |
1490 | return false; | |
1491 | ||
1492 | if (in_lto_p) | |
1493 | get_body (); | |
1494 | a = DECL_ARGUMENTS (thunk_fndecl); | |
1495 | ||
1496 | current_function_decl = thunk_fndecl; | |
1497 | ||
1498 | /* Ensure thunks are emitted in their correct sections. */ | |
1499 | resolve_unique_section (thunk_fndecl, 0, flag_function_sections); | |
1500 | ||
1501 | DECL_RESULT (thunk_fndecl) | |
1502 | = build_decl (DECL_SOURCE_LOCATION (thunk_fndecl), | |
1503 | RESULT_DECL, 0, restype); | |
1504 | DECL_CONTEXT (DECL_RESULT (thunk_fndecl)) = thunk_fndecl; | |
1505 | fnname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk_fndecl)); | |
1506 | ||
1507 | /* The back end expects DECL_INITIAL to contain a BLOCK, so we | |
1508 | create one. */ | |
1509 | fn_block = make_node (BLOCK); | |
1510 | BLOCK_VARS (fn_block) = a; | |
1511 | DECL_INITIAL (thunk_fndecl) = fn_block; | |
1512 | init_function_start (thunk_fndecl); | |
1513 | cfun->is_thunk = 1; | |
1514 | insn_locations_init (); | |
1515 | set_curr_insn_location (DECL_SOURCE_LOCATION (thunk_fndecl)); | |
1516 | prologue_location = curr_insn_location (); | |
1517 | assemble_start_function (thunk_fndecl, fnname); | |
1518 | ||
1519 | targetm.asm_out.output_mi_thunk (asm_out_file, thunk_fndecl, | |
1520 | fixed_offset, virtual_value, alias); | |
1521 | ||
1522 | assemble_end_function (thunk_fndecl, fnname); | |
1523 | insn_locations_finalize (); | |
1524 | init_insn_lengths (); | |
1525 | free_after_compilation (cfun); | |
1526 | set_cfun (NULL); | |
1527 | TREE_ASM_WRITTEN (thunk_fndecl) = 1; | |
1528 | thunk.thunk_p = false; | |
1529 | analyzed = false; | |
1530 | } | |
1531 | else | |
1532 | { | |
1533 | tree restype; | |
1534 | basic_block bb, then_bb, else_bb, return_bb; | |
1535 | gimple_stmt_iterator bsi; | |
1536 | int nargs = 0; | |
1537 | tree arg; | |
1538 | int i; | |
1539 | tree resdecl; | |
1540 | tree restmp = NULL; | |
1541 | ||
1542 | gimple call; | |
1543 | gimple ret; | |
1544 | ||
1545 | if (in_lto_p) | |
1546 | get_body (); | |
1547 | a = DECL_ARGUMENTS (thunk_fndecl); | |
1548 | ||
1549 | current_function_decl = thunk_fndecl; | |
1550 | ||
1551 | /* Ensure thunks are emitted in their correct sections. */ | |
1552 | resolve_unique_section (thunk_fndecl, 0, flag_function_sections); | |
1553 | ||
1554 | DECL_IGNORED_P (thunk_fndecl) = 1; | |
1555 | bitmap_obstack_initialize (NULL); | |
1556 | ||
1557 | if (thunk.virtual_offset_p) | |
1558 | virtual_offset = size_int (virtual_value); | |
1559 | ||
1560 | /* Build the return declaration for the function. */ | |
1561 | restype = TREE_TYPE (TREE_TYPE (thunk_fndecl)); | |
1562 | if (DECL_RESULT (thunk_fndecl) == NULL_TREE) | |
1563 | { | |
1564 | resdecl = build_decl (input_location, RESULT_DECL, 0, restype); | |
1565 | DECL_ARTIFICIAL (resdecl) = 1; | |
1566 | DECL_IGNORED_P (resdecl) = 1; | |
1567 | DECL_RESULT (thunk_fndecl) = resdecl; | |
1568 | DECL_CONTEXT (DECL_RESULT (thunk_fndecl)) = thunk_fndecl; | |
1569 | } | |
1570 | else | |
1571 | resdecl = DECL_RESULT (thunk_fndecl); | |
1572 | ||
1573 | bb = then_bb = else_bb = return_bb = init_lowered_empty_function (thunk_fndecl, true); | |
1574 | ||
1575 | bsi = gsi_start_bb (bb); | |
1576 | ||
1577 | /* Build call to the function being thunked. */ | |
1578 | if (!VOID_TYPE_P (restype)) | |
1579 | { | |
1580 | if (DECL_BY_REFERENCE (resdecl)) | |
1581 | restmp = gimple_fold_indirect_ref (resdecl); | |
1582 | else if (!is_gimple_reg_type (restype)) | |
1583 | { | |
1584 | restmp = resdecl; | |
1585 | add_local_decl (cfun, restmp); | |
1586 | BLOCK_VARS (DECL_INITIAL (current_function_decl)) = restmp; | |
1587 | } | |
1588 | else | |
1589 | restmp = create_tmp_reg (restype, "retval"); | |
1590 | } | |
1591 | ||
1592 | for (arg = a; arg; arg = DECL_CHAIN (arg)) | |
1593 | nargs++; | |
1594 | auto_vec<tree> vargs (nargs); | |
1595 | if (this_adjusting) | |
1596 | vargs.quick_push (thunk_adjust (&bsi, a, 1, fixed_offset, | |
1597 | virtual_offset)); | |
1598 | else if (nargs) | |
1599 | vargs.quick_push (a); | |
1600 | ||
1601 | if (nargs) | |
1602 | for (i = 1, arg = DECL_CHAIN (a); i < nargs; i++, arg = DECL_CHAIN (arg)) | |
1603 | { | |
1604 | tree tmp = arg; | |
1605 | if (!is_gimple_val (arg)) | |
1606 | { | |
1607 | tmp = create_tmp_reg (TYPE_MAIN_VARIANT | |
1608 | (TREE_TYPE (arg)), "arg"); | |
1609 | gimple stmt = gimple_build_assign (tmp, arg); | |
1610 | gsi_insert_after (&bsi, stmt, GSI_NEW_STMT); | |
1611 | } | |
1612 | vargs.quick_push (tmp); | |
1613 | } | |
1614 | call = gimple_build_call_vec (build_fold_addr_expr_loc (0, alias), vargs); | |
1615 | callees->call_stmt = call; | |
1616 | gimple_call_set_from_thunk (call, true); | |
1617 | if (restmp) | |
1618 | { | |
1619 | gimple_call_set_lhs (call, restmp); | |
1620 | gcc_assert (useless_type_conversion_p (TREE_TYPE (restmp), | |
1621 | TREE_TYPE (TREE_TYPE (alias)))); | |
1622 | } | |
1623 | gsi_insert_after (&bsi, call, GSI_NEW_STMT); | |
1624 | if (!(gimple_call_flags (call) & ECF_NORETURN)) | |
1625 | { | |
1626 | if (restmp && !this_adjusting | |
1627 | && (fixed_offset || virtual_offset)) | |
1628 | { | |
1629 | tree true_label = NULL_TREE; | |
1630 | ||
1631 | if (TREE_CODE (TREE_TYPE (restmp)) == POINTER_TYPE) | |
1632 | { | |
1633 | gimple stmt; | |
1634 | /* If the return type is a pointer, we need to | |
1635 | protect against NULL. We know there will be an | |
1636 | adjustment, because that's why we're emitting a | |
1637 | thunk. */ | |
1638 | then_bb = create_basic_block (NULL, (void *) 0, bb); | |
1639 | return_bb = create_basic_block (NULL, (void *) 0, then_bb); | |
1640 | else_bb = create_basic_block (NULL, (void *) 0, else_bb); | |
1641 | add_bb_to_loop (then_bb, bb->loop_father); | |
1642 | add_bb_to_loop (return_bb, bb->loop_father); | |
1643 | add_bb_to_loop (else_bb, bb->loop_father); | |
1644 | remove_edge (single_succ_edge (bb)); | |
1645 | true_label = gimple_block_label (then_bb); | |
1646 | stmt = gimple_build_cond (NE_EXPR, restmp, | |
1647 | build_zero_cst (TREE_TYPE (restmp)), | |
1648 | NULL_TREE, NULL_TREE); | |
1649 | gsi_insert_after (&bsi, stmt, GSI_NEW_STMT); | |
1650 | make_edge (bb, then_bb, EDGE_TRUE_VALUE); | |
1651 | make_edge (bb, else_bb, EDGE_FALSE_VALUE); | |
1652 | make_edge (return_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0); | |
1653 | make_edge (then_bb, return_bb, EDGE_FALLTHRU); | |
1654 | make_edge (else_bb, return_bb, EDGE_FALLTHRU); | |
1655 | bsi = gsi_last_bb (then_bb); | |
1656 | } | |
1657 | ||
1658 | restmp = thunk_adjust (&bsi, restmp, /*this_adjusting=*/0, | |
1659 | fixed_offset, virtual_offset); | |
1660 | if (true_label) | |
1661 | { | |
1662 | gimple stmt; | |
1663 | bsi = gsi_last_bb (else_bb); | |
1664 | stmt = gimple_build_assign (restmp, | |
1665 | build_zero_cst (TREE_TYPE (restmp))); | |
1666 | gsi_insert_after (&bsi, stmt, GSI_NEW_STMT); | |
1667 | bsi = gsi_last_bb (return_bb); | |
1668 | } | |
1669 | } | |
1670 | else | |
1671 | gimple_call_set_tail (call, true); | |
1672 | ||
1673 | /* Build return value. */ | |
1674 | ret = gimple_build_return (restmp); | |
1675 | gsi_insert_after (&bsi, ret, GSI_NEW_STMT); | |
1676 | } | |
1677 | else | |
1678 | { | |
1679 | gimple_call_set_tail (call, true); | |
1680 | remove_edge (single_succ_edge (bb)); | |
1681 | } | |
1682 | ||
1683 | cfun->gimple_df->in_ssa_p = true; | |
1684 | /* FIXME: C++ FE should stop setting TREE_ASM_WRITTEN on thunks. */ | |
1685 | TREE_ASM_WRITTEN (thunk_fndecl) = false; | |
1686 | delete_unreachable_blocks (); | |
1687 | update_ssa (TODO_update_ssa); | |
1688 | #ifdef ENABLE_CHECKING | |
1689 | verify_flow_info (); | |
1690 | #endif | |
1691 | free_dominance_info (CDI_DOMINATORS); | |
1692 | ||
1693 | /* Since we want to emit the thunk, we explicitly mark its name as | |
1694 | referenced. */ | |
1695 | thunk.thunk_p = false; | |
1696 | lowered = true; | |
1697 | bitmap_obstack_release (NULL); | |
1698 | } | |
1699 | current_function_decl = NULL; | |
1700 | set_cfun (NULL); | |
1701 | return true; | |
1702 | } | |
1703 | ||
1704 | /* Assemble thunks and aliases associated to NODE. */ | |
1705 | ||
1706 | static void | |
1707 | assemble_thunks_and_aliases (struct cgraph_node *node) | |
1708 | { | |
1709 | struct cgraph_edge *e; | |
1710 | struct ipa_ref *ref; | |
1711 | ||
1712 | for (e = node->callers; e;) | |
1713 | if (e->caller->thunk.thunk_p) | |
1714 | { | |
1715 | struct cgraph_node *thunk = e->caller; | |
1716 | ||
1717 | e = e->next_caller; | |
1718 | thunk->expand_thunk (true, false); | |
1719 | assemble_thunks_and_aliases (thunk); | |
1720 | } | |
1721 | else | |
1722 | e = e->next_caller; | |
1723 | ||
1724 | FOR_EACH_ALIAS (node, ref) | |
1725 | { | |
1726 | struct cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring); | |
1727 | bool saved_written = TREE_ASM_WRITTEN (node->decl); | |
1728 | ||
1729 | /* Force assemble_alias to really output the alias this time instead | |
1730 | of buffering it in same alias pairs. */ | |
1731 | TREE_ASM_WRITTEN (node->decl) = 1; | |
1732 | do_assemble_alias (alias->decl, | |
1733 | DECL_ASSEMBLER_NAME (node->decl)); | |
1734 | assemble_thunks_and_aliases (alias); | |
1735 | TREE_ASM_WRITTEN (node->decl) = saved_written; | |
1736 | } | |
1737 | } | |
1738 | ||
1739 | /* Expand function specified by NODE. */ | |
1740 | ||
1741 | static void | |
1742 | expand_function (struct cgraph_node *node) | |
1743 | { | |
1744 | tree decl = node->decl; | |
1745 | location_t saved_loc; | |
1746 | ||
1747 | /* We ought to not compile any inline clones. */ | |
1748 | gcc_assert (!node->global.inlined_to); | |
1749 | ||
1750 | announce_function (decl); | |
1751 | node->process = 0; | |
1752 | gcc_assert (node->lowered); | |
1753 | node->get_body (); | |
1754 | ||
1755 | /* Generate RTL for the body of DECL. */ | |
1756 | ||
1757 | timevar_push (TV_REST_OF_COMPILATION); | |
1758 | ||
1759 | gcc_assert (cgraph_global_info_ready); | |
1760 | ||
1761 | /* Initialize the default bitmap obstack. */ | |
1762 | bitmap_obstack_initialize (NULL); | |
1763 | ||
1764 | /* Initialize the RTL code for the function. */ | |
1765 | current_function_decl = decl; | |
1766 | saved_loc = input_location; | |
1767 | input_location = DECL_SOURCE_LOCATION (decl); | |
1768 | init_function_start (decl); | |
1769 | ||
1770 | gimple_register_cfg_hooks (); | |
1771 | ||
1772 | bitmap_obstack_initialize (®_obstack); /* FIXME, only at RTL generation*/ | |
1773 | ||
1774 | execute_all_ipa_transforms (); | |
1775 | ||
1776 | /* Perform all tree transforms and optimizations. */ | |
1777 | ||
1778 | /* Signal the start of passes. */ | |
1779 | invoke_plugin_callbacks (PLUGIN_ALL_PASSES_START, NULL); | |
1780 | ||
1781 | execute_pass_list (cfun, g->get_passes ()->all_passes); | |
1782 | ||
1783 | /* Signal the end of passes. */ | |
1784 | invoke_plugin_callbacks (PLUGIN_ALL_PASSES_END, NULL); | |
1785 | ||
1786 | bitmap_obstack_release (®_obstack); | |
1787 | ||
1788 | /* Release the default bitmap obstack. */ | |
1789 | bitmap_obstack_release (NULL); | |
1790 | ||
1791 | /* If requested, warn about function definitions where the function will | |
1792 | return a value (usually of some struct or union type) which itself will | |
1793 | take up a lot of stack space. */ | |
1794 | if (warn_larger_than && !DECL_EXTERNAL (decl) && TREE_TYPE (decl)) | |
1795 | { | |
1796 | tree ret_type = TREE_TYPE (TREE_TYPE (decl)); | |
1797 | ||
1798 | if (ret_type && TYPE_SIZE_UNIT (ret_type) | |
1799 | && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST | |
1800 | && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type), | |
1801 | larger_than_size)) | |
1802 | { | |
1803 | unsigned int size_as_int | |
1804 | = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type)); | |
1805 | ||
1806 | if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0) | |
1807 | warning (OPT_Wlarger_than_, "size of return value of %q+D is %u bytes", | |
1808 | decl, size_as_int); | |
1809 | else | |
1810 | warning (OPT_Wlarger_than_, "size of return value of %q+D is larger than %wd bytes", | |
1811 | decl, larger_than_size); | |
1812 | } | |
1813 | } | |
1814 | ||
1815 | gimple_set_body (decl, NULL); | |
1816 | if (DECL_STRUCT_FUNCTION (decl) == 0 | |
1817 | && !cgraph_node::get (decl)->origin) | |
1818 | { | |
1819 | /* Stop pointing to the local nodes about to be freed. | |
1820 | But DECL_INITIAL must remain nonzero so we know this | |
1821 | was an actual function definition. | |
1822 | For a nested function, this is done in c_pop_function_context. | |
1823 | If rest_of_compilation set this to 0, leave it 0. */ | |
1824 | if (DECL_INITIAL (decl) != 0) | |
1825 | DECL_INITIAL (decl) = error_mark_node; | |
1826 | } | |
1827 | ||
1828 | input_location = saved_loc; | |
1829 | ||
1830 | ggc_collect (); | |
1831 | timevar_pop (TV_REST_OF_COMPILATION); | |
1832 | ||
1833 | /* Make sure that BE didn't give up on compiling. */ | |
1834 | gcc_assert (TREE_ASM_WRITTEN (decl)); | |
1835 | set_cfun (NULL); | |
1836 | current_function_decl = NULL; | |
1837 | ||
1838 | /* It would make a lot more sense to output thunks before function body to get more | |
1839 | forward and lest backwarding jumps. This however would need solving problem | |
1840 | with comdats. See PR48668. Also aliases must come after function itself to | |
1841 | make one pass assemblers, like one on AIX, happy. See PR 50689. | |
1842 | FIXME: Perhaps thunks should be move before function IFF they are not in comdat | |
1843 | groups. */ | |
1844 | assemble_thunks_and_aliases (node); | |
1845 | node->release_body (); | |
1846 | /* Eliminate all call edges. This is important so the GIMPLE_CALL no longer | |
1847 | points to the dead function body. */ | |
1848 | node->remove_callees (); | |
1849 | node->remove_all_references (); | |
1850 | } | |
1851 | ||
1852 | /* Node comparer that is responsible for the order that corresponds | |
1853 | to time when a function was launched for the first time. */ | |
1854 | ||
1855 | static int | |
1856 | node_cmp (const void *pa, const void *pb) | |
1857 | { | |
1858 | const struct cgraph_node *a = *(const struct cgraph_node * const *) pa; | |
1859 | const struct cgraph_node *b = *(const struct cgraph_node * const *) pb; | |
1860 | ||
1861 | /* Functions with time profile must be before these without profile. */ | |
1862 | if (!a->tp_first_run || !b->tp_first_run) | |
1863 | return a->tp_first_run - b->tp_first_run; | |
1864 | ||
1865 | return a->tp_first_run != b->tp_first_run | |
1866 | ? b->tp_first_run - a->tp_first_run | |
1867 | : b->order - a->order; | |
1868 | } | |
1869 | ||
1870 | /* Expand all functions that must be output. | |
1871 | ||
1872 | Attempt to topologically sort the nodes so function is output when | |
1873 | all called functions are already assembled to allow data to be | |
1874 | propagated across the callgraph. Use a stack to get smaller distance | |
1875 | between a function and its callees (later we may choose to use a more | |
1876 | sophisticated algorithm for function reordering; we will likely want | |
1877 | to use subsections to make the output functions appear in top-down | |
1878 | order). */ | |
1879 | ||
1880 | static void | |
1881 | expand_all_functions (void) | |
1882 | { | |
1883 | struct cgraph_node *node; | |
1884 | struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes); | |
1885 | unsigned int expanded_func_count = 0, profiled_func_count = 0; | |
1886 | int order_pos, new_order_pos = 0; | |
1887 | int i; | |
1888 | ||
1889 | order_pos = ipa_reverse_postorder (order); | |
1890 | gcc_assert (order_pos == cgraph_n_nodes); | |
1891 | ||
1892 | /* Garbage collector may remove inline clones we eliminate during | |
1893 | optimization. So we must be sure to not reference them. */ | |
1894 | for (i = 0; i < order_pos; i++) | |
1895 | if (order[i]->process) | |
1896 | order[new_order_pos++] = order[i]; | |
1897 | ||
1898 | if (flag_profile_reorder_functions) | |
1899 | qsort (order, new_order_pos, sizeof (struct cgraph_node *), node_cmp); | |
1900 | ||
1901 | for (i = new_order_pos - 1; i >= 0; i--) | |
1902 | { | |
1903 | node = order[i]; | |
1904 | ||
1905 | if (node->process) | |
1906 | { | |
1907 | expanded_func_count++; | |
1908 | if(node->tp_first_run) | |
1909 | profiled_func_count++; | |
1910 | ||
1911 | if (cgraph_dump_file) | |
1912 | fprintf (cgraph_dump_file, "Time profile order in expand_all_functions:%s:%d\n", node->asm_name (), node->tp_first_run); | |
1913 | ||
1914 | node->process = 0; | |
1915 | expand_function (node); | |
1916 | } | |
1917 | } | |
1918 | ||
1919 | if (dump_file) | |
1920 | fprintf (dump_file, "Expanded functions with time profile (%s):%u/%u\n", | |
1921 | main_input_filename, profiled_func_count, expanded_func_count); | |
1922 | ||
1923 | if (cgraph_dump_file && flag_profile_reorder_functions) | |
1924 | fprintf (cgraph_dump_file, "Expanded functions with time profile:%u/%u\n", | |
1925 | profiled_func_count, expanded_func_count); | |
1926 | ||
1927 | cgraph_process_new_functions (); | |
1928 | free_gimplify_stack (); | |
1929 | ||
1930 | free (order); | |
1931 | } | |
1932 | ||
1933 | /* This is used to sort the node types by the cgraph order number. */ | |
1934 | ||
1935 | enum cgraph_order_sort_kind | |
1936 | { | |
1937 | ORDER_UNDEFINED = 0, | |
1938 | ORDER_FUNCTION, | |
1939 | ORDER_VAR, | |
1940 | ORDER_ASM | |
1941 | }; | |
1942 | ||
1943 | struct cgraph_order_sort | |
1944 | { | |
1945 | enum cgraph_order_sort_kind kind; | |
1946 | union | |
1947 | { | |
1948 | struct cgraph_node *f; | |
1949 | varpool_node *v; | |
1950 | struct asm_node *a; | |
1951 | } u; | |
1952 | }; | |
1953 | ||
1954 | /* Output all functions, variables, and asm statements in the order | |
1955 | according to their order fields, which is the order in which they | |
1956 | appeared in the file. This implements -fno-toplevel-reorder. In | |
1957 | this mode we may output functions and variables which don't really | |
1958 | need to be output. */ | |
1959 | ||
1960 | static void | |
1961 | output_in_order (void) | |
1962 | { | |
1963 | int max; | |
1964 | struct cgraph_order_sort *nodes; | |
1965 | int i; | |
1966 | struct cgraph_node *pf; | |
1967 | varpool_node *pv; | |
1968 | struct asm_node *pa; | |
1969 | ||
1970 | max = symtab_order; | |
1971 | nodes = XCNEWVEC (struct cgraph_order_sort, max); | |
1972 | ||
1973 | FOR_EACH_DEFINED_FUNCTION (pf) | |
1974 | { | |
1975 | if (pf->process && !pf->thunk.thunk_p && !pf->alias) | |
1976 | { | |
1977 | i = pf->order; | |
1978 | gcc_assert (nodes[i].kind == ORDER_UNDEFINED); | |
1979 | nodes[i].kind = ORDER_FUNCTION; | |
1980 | nodes[i].u.f = pf; | |
1981 | } | |
1982 | } | |
1983 | ||
1984 | FOR_EACH_DEFINED_VARIABLE (pv) | |
1985 | if (!DECL_EXTERNAL (pv->decl)) | |
1986 | { | |
1987 | i = pv->order; | |
1988 | gcc_assert (nodes[i].kind == ORDER_UNDEFINED); | |
1989 | nodes[i].kind = ORDER_VAR; | |
1990 | nodes[i].u.v = pv; | |
1991 | } | |
1992 | ||
1993 | for (pa = asm_nodes; pa; pa = pa->next) | |
1994 | { | |
1995 | i = pa->order; | |
1996 | gcc_assert (nodes[i].kind == ORDER_UNDEFINED); | |
1997 | nodes[i].kind = ORDER_ASM; | |
1998 | nodes[i].u.a = pa; | |
1999 | } | |
2000 | ||
2001 | /* In toplevel reorder mode we output all statics; mark them as needed. */ | |
2002 | ||
2003 | for (i = 0; i < max; ++i) | |
2004 | if (nodes[i].kind == ORDER_VAR) | |
2005 | nodes[i].u.v->finalize_named_section_flags (); | |
2006 | ||
2007 | for (i = 0; i < max; ++i) | |
2008 | { | |
2009 | switch (nodes[i].kind) | |
2010 | { | |
2011 | case ORDER_FUNCTION: | |
2012 | nodes[i].u.f->process = 0; | |
2013 | expand_function (nodes[i].u.f); | |
2014 | break; | |
2015 | ||
2016 | case ORDER_VAR: | |
2017 | nodes[i].u.v->assemble_decl (); | |
2018 | break; | |
2019 | ||
2020 | case ORDER_ASM: | |
2021 | assemble_asm (nodes[i].u.a->asm_str); | |
2022 | break; | |
2023 | ||
2024 | case ORDER_UNDEFINED: | |
2025 | break; | |
2026 | ||
2027 | default: | |
2028 | gcc_unreachable (); | |
2029 | } | |
2030 | } | |
2031 | ||
2032 | asm_nodes = NULL; | |
2033 | free (nodes); | |
2034 | } | |
2035 | ||
2036 | static void | |
2037 | ipa_passes (void) | |
2038 | { | |
2039 | gcc::pass_manager *passes = g->get_passes (); | |
2040 | ||
2041 | set_cfun (NULL); | |
2042 | current_function_decl = NULL; | |
2043 | gimple_register_cfg_hooks (); | |
2044 | bitmap_obstack_initialize (NULL); | |
2045 | ||
2046 | invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_START, NULL); | |
2047 | ||
2048 | if (!in_lto_p) | |
2049 | { | |
2050 | execute_ipa_pass_list (passes->all_small_ipa_passes); | |
2051 | if (seen_error ()) | |
2052 | return; | |
2053 | } | |
2054 | ||
2055 | /* We never run removal of unreachable nodes after early passes. This is | |
2056 | because TODO is run before the subpasses. It is important to remove | |
2057 | the unreachable functions to save works at IPA level and to get LTO | |
2058 | symbol tables right. */ | |
2059 | symtab_remove_unreachable_nodes (true, cgraph_dump_file); | |
2060 | ||
2061 | /* If pass_all_early_optimizations was not scheduled, the state of | |
2062 | the cgraph will not be properly updated. Update it now. */ | |
2063 | if (cgraph_state < CGRAPH_STATE_IPA_SSA) | |
2064 | cgraph_state = CGRAPH_STATE_IPA_SSA; | |
2065 | ||
2066 | if (!in_lto_p) | |
2067 | { | |
2068 | /* Generate coverage variables and constructors. */ | |
2069 | coverage_finish (); | |
2070 | ||
2071 | /* Process new functions added. */ | |
2072 | set_cfun (NULL); | |
2073 | current_function_decl = NULL; | |
2074 | cgraph_process_new_functions (); | |
2075 | ||
2076 | execute_ipa_summary_passes | |
2077 | ((ipa_opt_pass_d *) passes->all_regular_ipa_passes); | |
2078 | } | |
2079 | ||
2080 | /* Some targets need to handle LTO assembler output specially. */ | |
2081 | if (flag_generate_lto) | |
2082 | targetm.asm_out.lto_start (); | |
2083 | ||
2084 | if (!in_lto_p) | |
2085 | ipa_write_summaries (); | |
2086 | ||
2087 | if (flag_generate_lto) | |
2088 | targetm.asm_out.lto_end (); | |
2089 | ||
2090 | if (!flag_ltrans && (in_lto_p || !flag_lto || flag_fat_lto_objects)) | |
2091 | execute_ipa_pass_list (passes->all_regular_ipa_passes); | |
2092 | invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_END, NULL); | |
2093 | ||
2094 | bitmap_obstack_release (NULL); | |
2095 | } | |
2096 | ||
2097 | ||
2098 | /* Return string alias is alias of. */ | |
2099 | ||
2100 | static tree | |
2101 | get_alias_symbol (tree decl) | |
2102 | { | |
2103 | tree alias = lookup_attribute ("alias", DECL_ATTRIBUTES (decl)); | |
2104 | return get_identifier (TREE_STRING_POINTER | |
2105 | (TREE_VALUE (TREE_VALUE (alias)))); | |
2106 | } | |
2107 | ||
2108 | ||
2109 | /* Weakrefs may be associated to external decls and thus not output | |
2110 | at expansion time. Emit all necessary aliases. */ | |
2111 | ||
2112 | static void | |
2113 | output_weakrefs (void) | |
2114 | { | |
2115 | symtab_node *node; | |
2116 | FOR_EACH_SYMBOL (node) | |
2117 | if (node->alias | |
2118 | && !TREE_ASM_WRITTEN (node->decl) | |
2119 | && node->weakref) | |
2120 | { | |
2121 | tree target; | |
2122 | ||
2123 | /* Weakrefs are special by not requiring target definition in current | |
2124 | compilation unit. It is thus bit hard to work out what we want to | |
2125 | alias. | |
2126 | When alias target is defined, we need to fetch it from symtab reference, | |
2127 | otherwise it is pointed to by alias_target. */ | |
2128 | if (node->alias_target) | |
2129 | target = (DECL_P (node->alias_target) | |
2130 | ? DECL_ASSEMBLER_NAME (node->alias_target) | |
2131 | : node->alias_target); | |
2132 | else if (node->analyzed) | |
2133 | target = DECL_ASSEMBLER_NAME (node->get_alias_target ()->decl); | |
2134 | else | |
2135 | { | |
2136 | gcc_unreachable (); | |
2137 | target = get_alias_symbol (node->decl); | |
2138 | } | |
2139 | do_assemble_alias (node->decl, target); | |
2140 | } | |
2141 | } | |
2142 | ||
2143 | /* Initialize callgraph dump file. */ | |
2144 | ||
2145 | void | |
2146 | init_cgraph (void) | |
2147 | { | |
2148 | if (!cgraph_dump_file) | |
2149 | cgraph_dump_file = dump_begin (TDI_cgraph, NULL); | |
2150 | } | |
2151 | ||
2152 | ||
2153 | /* Perform simple optimizations based on callgraph. */ | |
2154 | ||
2155 | void | |
2156 | compile (void) | |
2157 | { | |
2158 | if (seen_error ()) | |
2159 | return; | |
2160 | ||
2161 | #ifdef ENABLE_CHECKING | |
2162 | symtab_node::verify_symtab_nodes (); | |
2163 | #endif | |
2164 | ||
2165 | timevar_push (TV_CGRAPHOPT); | |
2166 | if (pre_ipa_mem_report) | |
2167 | { | |
2168 | fprintf (stderr, "Memory consumption before IPA\n"); | |
2169 | dump_memory_report (false); | |
2170 | } | |
2171 | if (!quiet_flag) | |
2172 | fprintf (stderr, "Performing interprocedural optimizations\n"); | |
2173 | cgraph_state = CGRAPH_STATE_IPA; | |
2174 | ||
2175 | /* If LTO is enabled, initialize the streamer hooks needed by GIMPLE. */ | |
2176 | if (flag_lto) | |
2177 | lto_streamer_hooks_init (); | |
2178 | ||
2179 | /* Don't run the IPA passes if there was any error or sorry messages. */ | |
2180 | if (!seen_error ()) | |
2181 | ipa_passes (); | |
2182 | ||
2183 | /* Do nothing else if any IPA pass found errors or if we are just streaming LTO. */ | |
2184 | if (seen_error () | |
2185 | || (!in_lto_p && flag_lto && !flag_fat_lto_objects)) | |
2186 | { | |
2187 | timevar_pop (TV_CGRAPHOPT); | |
2188 | return; | |
2189 | } | |
2190 | ||
2191 | /* This pass remove bodies of extern inline functions we never inlined. | |
2192 | Do this later so other IPA passes see what is really going on. */ | |
2193 | symtab_remove_unreachable_nodes (false, dump_file); | |
2194 | cgraph_global_info_ready = true; | |
2195 | if (cgraph_dump_file) | |
2196 | { | |
2197 | fprintf (cgraph_dump_file, "Optimized "); | |
2198 | symtab_node:: dump_table (cgraph_dump_file); | |
2199 | } | |
2200 | if (post_ipa_mem_report) | |
2201 | { | |
2202 | fprintf (stderr, "Memory consumption after IPA\n"); | |
2203 | dump_memory_report (false); | |
2204 | } | |
2205 | timevar_pop (TV_CGRAPHOPT); | |
2206 | ||
2207 | /* Output everything. */ | |
2208 | (*debug_hooks->assembly_start) (); | |
2209 | if (!quiet_flag) | |
2210 | fprintf (stderr, "Assembling functions:\n"); | |
2211 | #ifdef ENABLE_CHECKING | |
2212 | symtab_node::verify_symtab_nodes (); | |
2213 | #endif | |
2214 | ||
2215 | cgraph_materialize_all_clones (); | |
2216 | bitmap_obstack_initialize (NULL); | |
2217 | execute_ipa_pass_list (g->get_passes ()->all_late_ipa_passes); | |
2218 | symtab_remove_unreachable_nodes (true, dump_file); | |
2219 | #ifdef ENABLE_CHECKING | |
2220 | symtab_node::verify_symtab_nodes (); | |
2221 | #endif | |
2222 | bitmap_obstack_release (NULL); | |
2223 | mark_functions_to_output (); | |
2224 | ||
2225 | /* When weakref support is missing, we autmatically translate all | |
2226 | references to NODE to references to its ultimate alias target. | |
2227 | The renaming mechanizm uses flag IDENTIFIER_TRANSPARENT_ALIAS and | |
2228 | TREE_CHAIN. | |
2229 | ||
2230 | Set up this mapping before we output any assembler but once we are sure | |
2231 | that all symbol renaming is done. | |
2232 | ||
2233 | FIXME: All this uglyness can go away if we just do renaming at gimple | |
2234 | level by physically rewritting the IL. At the moment we can only redirect | |
2235 | calls, so we need infrastructure for renaming references as well. */ | |
2236 | #ifndef ASM_OUTPUT_WEAKREF | |
2237 | symtab_node *node; | |
2238 | ||
2239 | FOR_EACH_SYMBOL (node) | |
2240 | if (node->alias | |
2241 | && lookup_attribute ("weakref", DECL_ATTRIBUTES (node->decl))) | |
2242 | { | |
2243 | IDENTIFIER_TRANSPARENT_ALIAS | |
2244 | (DECL_ASSEMBLER_NAME (node->decl)) = 1; | |
2245 | TREE_CHAIN (DECL_ASSEMBLER_NAME (node->decl)) | |
2246 | = (node->alias_target ? node->alias_target | |
2247 | : DECL_ASSEMBLER_NAME (node->get_alias_target ()->decl)); | |
2248 | } | |
2249 | #endif | |
2250 | ||
2251 | cgraph_state = CGRAPH_STATE_EXPANSION; | |
2252 | ||
2253 | if (!flag_toplevel_reorder) | |
2254 | output_in_order (); | |
2255 | else | |
2256 | { | |
2257 | output_asm_statements (); | |
2258 | ||
2259 | expand_all_functions (); | |
2260 | varpool_node::output_variables (); | |
2261 | } | |
2262 | ||
2263 | cgraph_process_new_functions (); | |
2264 | cgraph_state = CGRAPH_STATE_FINISHED; | |
2265 | output_weakrefs (); | |
2266 | ||
2267 | if (cgraph_dump_file) | |
2268 | { | |
2269 | fprintf (cgraph_dump_file, "\nFinal "); | |
2270 | symtab_node::dump_table (cgraph_dump_file); | |
2271 | } | |
2272 | #ifdef ENABLE_CHECKING | |
2273 | symtab_node::verify_symtab_nodes (); | |
2274 | /* Double check that all inline clones are gone and that all | |
2275 | function bodies have been released from memory. */ | |
2276 | if (!seen_error ()) | |
2277 | { | |
2278 | struct cgraph_node *node; | |
2279 | bool error_found = false; | |
2280 | ||
2281 | FOR_EACH_DEFINED_FUNCTION (node) | |
2282 | if (node->global.inlined_to | |
2283 | || gimple_has_body_p (node->decl)) | |
2284 | { | |
2285 | error_found = true; | |
2286 | node->debug (); | |
2287 | } | |
2288 | if (error_found) | |
2289 | internal_error ("nodes with unreleased memory found"); | |
2290 | } | |
2291 | #endif | |
2292 | } | |
2293 | ||
2294 | ||
2295 | /* Analyze the whole compilation unit once it is parsed completely. */ | |
2296 | ||
2297 | void | |
2298 | finalize_compilation_unit (void) | |
2299 | { | |
2300 | timevar_push (TV_CGRAPH); | |
2301 | ||
2302 | /* If we're here there's no current function anymore. Some frontends | |
2303 | are lazy in clearing these. */ | |
2304 | current_function_decl = NULL; | |
2305 | set_cfun (NULL); | |
2306 | ||
2307 | /* Do not skip analyzing the functions if there were errors, we | |
2308 | miss diagnostics for following functions otherwise. */ | |
2309 | ||
2310 | /* Emit size functions we didn't inline. */ | |
2311 | finalize_size_functions (); | |
2312 | ||
2313 | /* Mark alias targets necessary and emit diagnostics. */ | |
2314 | handle_alias_pairs (); | |
2315 | ||
2316 | if (!quiet_flag) | |
2317 | { | |
2318 | fprintf (stderr, "\nAnalyzing compilation unit\n"); | |
2319 | fflush (stderr); | |
2320 | } | |
2321 | ||
2322 | if (flag_dump_passes) | |
2323 | dump_passes (); | |
2324 | ||
2325 | /* Gimplify and lower all functions, compute reachability and | |
2326 | remove unreachable nodes. */ | |
2327 | analyze_functions (); | |
2328 | ||
2329 | /* Mark alias targets necessary and emit diagnostics. */ | |
2330 | handle_alias_pairs (); | |
2331 | ||
2332 | /* Gimplify and lower thunks. */ | |
2333 | analyze_functions (); | |
2334 | ||
2335 | /* Finally drive the pass manager. */ | |
2336 | compile (); | |
2337 | ||
2338 | timevar_pop (TV_CGRAPH); | |
2339 | } | |
2340 | ||
2341 | /* Creates a wrapper from cgraph_node to TARGET node. Thunk is used for this | |
2342 | kind of wrapper method. */ | |
2343 | ||
2344 | void | |
2345 | cgraph_node::create_wrapper (struct cgraph_node *target) | |
2346 | { | |
2347 | /* Preserve DECL_RESULT so we get right by reference flag. */ | |
2348 | tree decl_result = DECL_RESULT (decl); | |
2349 | ||
2350 | /* Remove the function's body. */ | |
2351 | release_body (); | |
2352 | reset (); | |
2353 | ||
2354 | DECL_RESULT (decl) = decl_result; | |
2355 | DECL_INITIAL (decl) = NULL; | |
2356 | allocate_struct_function (decl, false); | |
2357 | set_cfun (NULL); | |
2358 | ||
2359 | /* Turn alias into thunk and expand it into GIMPLE representation. */ | |
2360 | definition = true; | |
2361 | thunk.thunk_p = true; | |
2362 | thunk.this_adjusting = false; | |
2363 | ||
2364 | struct cgraph_edge *e = create_edge (target, NULL, 0, CGRAPH_FREQ_BASE); | |
2365 | ||
2366 | if (!expand_thunk (false, true)) | |
2367 | analyzed = true; | |
2368 | ||
2369 | e->call_stmt_cannot_inline_p = true; | |
2370 | ||
2371 | /* Inline summary set-up. */ | |
2372 | analyze (); | |
2373 | inline_analyze_function (this); | |
2374 | } | |
2375 | ||
2376 | #include "gt-cgraphunit.h" |