1 /* Callgraph based interprocedural optimizations.
2 Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka
6 This file is part of GCC.
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
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
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/>. */
22 /* This module implements main driver of compilation process as well as
23 few basic interprocedural optimizers.
25 The main scope of this file is to act as an interface in between
26 tree based frontends and the backend (and middle end)
28 The front-end is supposed to use following functionality:
30 - cgraph_finalize_function
32 This function is called once front-end has parsed whole body of function
33 and it is certain that the function body nor the declaration will change.
35 (There is one exception needed for implementing GCC extern inline
38 - varpool_finalize_variable
40 This function has same behavior as the above but is used for static
43 - cgraph_finalize_compilation_unit
45 This function is called once (source level) compilation unit is finalized
46 and it will no longer change.
48 In the the call-graph construction and local function
49 analysis takes place here. Bodies of unreachable functions are released
50 to conserve memory usage.
52 The function can be called multiple times when multiple source level
53 compilation units are combined (such as in C frontend)
57 In this unit-at-a-time compilation the intra procedural analysis takes
58 place here. In particular the static functions whose address is never
59 taken are marked as local. Backend can then use this information to
60 modify calling conventions, do better inlining or similar optimizations.
62 - cgraph_mark_needed_node
63 - varpool_mark_needed_node
65 When function or variable is referenced by some hidden way the call-graph
66 data structure must be updated accordingly by this function.
67 There should be little need to call this function and all the references
68 should be made explicit to cgraph code. At present these functions are
69 used by C++ frontend to explicitly mark the keyed methods.
71 - analyze_expr callback
73 This function is responsible for lowering tree nodes not understood by
74 generic code into understandable ones or alternatively marking
75 callgraph and varpool nodes referenced by the as needed.
77 ??? On the tree-ssa genericizing should take place here and we will avoid
78 need for these hooks (replacing them by genericizing hook)
80 Analyzing of all functions is deferred
81 to cgraph_finalize_compilation_unit and expansion into cgraph_optimize.
83 In cgraph_finalize_compilation_unit the reachable functions are
84 analyzed. During analysis the call-graph edges from reachable
85 functions are constructed and their destinations are marked as
86 reachable. References to functions and variables are discovered too
87 and variables found to be needed output to the assembly file. Via
88 mark_referenced call in assemble_variable functions referenced by
89 static variables are noticed too.
91 The intra-procedural information is produced and its existence
92 indicated by global_info_ready. Once this flag is set it is impossible
93 to change function from !reachable to reachable and thus
94 assemble_variable no longer call mark_referenced.
96 Finally the call-graph is topologically sorted and all reachable functions
97 that has not been completely inlined or are not external are output.
99 ??? It is possible that reference to function or variable is optimized
100 out. We can not deal with this nicely because topological order is not
101 suitable for it. For tree-ssa we may consider another pass doing
102 optimization and re-discovering reachable functions.
104 ??? Reorganize code so variables are output very last and only if they
105 really has been referenced by produced code, so we catch more cases
106 where reference has been optimized out. */
111 #include "coretypes.h"
115 #include "tree-flow.h"
116 #include "tree-inline.h"
117 #include "langhooks.h"
118 #include "pointer-set.h"
125 #include "diagnostic.h"
130 #include "function.h"
131 #include "ipa-prop.h"
133 #include "tree-iterator.h"
134 #include "tree-pass.h"
135 #include "tree-dump.h"
137 #include "coverage.h"
140 static void cgraph_expand_all_functions (void);
141 static void cgraph_mark_functions_to_output (void);
142 static void cgraph_expand_function (struct cgraph_node *);
143 static void cgraph_output_pending_asms (void);
144 static void cgraph_analyze_function (struct cgraph_node *);
146 static FILE *cgraph_dump_file;
148 /* A vector of FUNCTION_DECLs declared as static constructors. */
149 static GTY (()) VEC(tree, gc) *static_ctors;
150 /* A vector of FUNCTION_DECLs declared as static destructors. */
151 static GTY (()) VEC(tree, gc) *static_dtors;
153 /* Used for vtable lookup in thunk adjusting. */
154 static GTY (()) tree vtable_entry_type;
156 /* When target does not have ctors and dtors, we call all constructor
157 and destructor by special initialization/destruction function
158 recognized by collect2.
160 When we are going to build this function, collect all constructors and
161 destructors and turn them into normal functions. */
164 record_cdtor_fn (tree fndecl)
166 struct cgraph_node *node;
167 if (targetm.have_ctors_dtors
168 || (!DECL_STATIC_CONSTRUCTOR (fndecl)
169 && !DECL_STATIC_DESTRUCTOR (fndecl)))
172 if (DECL_STATIC_CONSTRUCTOR (fndecl))
174 VEC_safe_push (tree, gc, static_ctors, fndecl);
175 DECL_STATIC_CONSTRUCTOR (fndecl) = 0;
177 if (DECL_STATIC_DESTRUCTOR (fndecl))
179 VEC_safe_push (tree, gc, static_dtors, fndecl);
180 DECL_STATIC_DESTRUCTOR (fndecl) = 0;
182 node = cgraph_node (fndecl);
183 node->local.disregard_inline_limits = 1;
184 cgraph_mark_reachable_node (node);
187 /* Define global constructors/destructor functions for the CDTORS, of
188 which they are LEN. The CDTORS are sorted by initialization
189 priority. If CTOR_P is true, these are constructors; otherwise,
190 they are destructors. */
193 build_cdtor (bool ctor_p, tree *cdtors, size_t len)
202 priority_type priority;
206 /* Find the next batch of constructors/destructors with the same
207 initialization priority. */
212 p = ctor_p ? DECL_INIT_PRIORITY (fn) : DECL_FINI_PRIORITY (fn);
215 else if (p != priority)
217 append_to_statement_list (build_function_call_expr (UNKNOWN_LOCATION,
223 gcc_assert (body != NULL_TREE);
224 /* Generate a function to call all the function of like
226 cgraph_build_static_cdtor (ctor_p ? 'I' : 'D', body, priority);
230 /* Comparison function for qsort. P1 and P2 are actually of type
231 "tree *" and point to static constructors. DECL_INIT_PRIORITY is
232 used to determine the sort order. */
235 compare_ctor (const void *p1, const void *p2)
242 f1 = *(const tree *)p1;
243 f2 = *(const tree *)p2;
244 priority1 = DECL_INIT_PRIORITY (f1);
245 priority2 = DECL_INIT_PRIORITY (f2);
247 if (priority1 < priority2)
249 else if (priority1 > priority2)
252 /* Ensure a stable sort. */
253 return (const tree *)p1 - (const tree *)p2;
256 /* Comparison function for qsort. P1 and P2 are actually of type
257 "tree *" and point to static destructors. DECL_FINI_PRIORITY is
258 used to determine the sort order. */
261 compare_dtor (const void *p1, const void *p2)
268 f1 = *(const tree *)p1;
269 f2 = *(const tree *)p2;
270 priority1 = DECL_FINI_PRIORITY (f1);
271 priority2 = DECL_FINI_PRIORITY (f2);
273 if (priority1 < priority2)
275 else if (priority1 > priority2)
278 /* Ensure a stable sort. */
279 return (const tree *)p1 - (const tree *)p2;
282 /* Generate functions to call static constructors and destructors
283 for targets that do not support .ctors/.dtors sections. These
284 functions have magic names which are detected by collect2. */
287 cgraph_build_cdtor_fns (void)
289 if (!VEC_empty (tree, static_ctors))
291 gcc_assert (!targetm.have_ctors_dtors);
292 qsort (VEC_address (tree, static_ctors),
293 VEC_length (tree, static_ctors),
296 build_cdtor (/*ctor_p=*/true,
297 VEC_address (tree, static_ctors),
298 VEC_length (tree, static_ctors));
299 VEC_truncate (tree, static_ctors, 0);
302 if (!VEC_empty (tree, static_dtors))
304 gcc_assert (!targetm.have_ctors_dtors);
305 qsort (VEC_address (tree, static_dtors),
306 VEC_length (tree, static_dtors),
309 build_cdtor (/*ctor_p=*/false,
310 VEC_address (tree, static_dtors),
311 VEC_length (tree, static_dtors));
312 VEC_truncate (tree, static_dtors, 0);
316 /* Determine if function DECL is needed. That is, visible to something
317 either outside this translation unit, something magic in the system
321 cgraph_decide_is_function_needed (struct cgraph_node *node, tree decl)
323 /* If the user told us it is used, then it must be so. */
324 if (node->local.externally_visible)
327 /* ??? If the assembler name is set by hand, it is possible to assemble
328 the name later after finalizing the function and the fact is noticed
329 in assemble_name then. This is arguably a bug. */
330 if (DECL_ASSEMBLER_NAME_SET_P (decl)
331 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
334 /* With -fkeep-inline-functions we are keeping all inline functions except
335 for extern inline ones. */
336 if (flag_keep_inline_functions
337 && DECL_DECLARED_INLINE_P (decl)
338 && !DECL_EXTERNAL (decl)
339 && !lookup_attribute ("always_inline", DECL_ATTRIBUTES (decl)))
342 /* If we decided it was needed before, but at the time we didn't have
343 the body of the function available, then it's still needed. We have
344 to go back and re-check its dependencies now. */
348 /* Externally visible functions must be output. The exception is
349 COMDAT functions that must be output only when they are needed.
351 When not optimizing, also output the static functions. (see
352 PR24561), but don't do so for always_inline functions, functions
353 declared inline and nested functions. These was optimized out
354 in the original implementation and it is unclear whether we want
355 to change the behavior here. */
356 if (((TREE_PUBLIC (decl)
357 || (!optimize && !node->local.disregard_inline_limits
358 && !DECL_DECLARED_INLINE_P (decl)
360 && !flag_whole_program
363 && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
366 /* Constructors and destructors are reachable from the runtime by
368 if (DECL_STATIC_CONSTRUCTOR (decl) || DECL_STATIC_DESTRUCTOR (decl))
374 /* Process CGRAPH_NEW_FUNCTIONS and perform actions necessary to add these
375 functions into callgraph in a way so they look like ordinary reachable
376 functions inserted into callgraph already at construction time. */
379 cgraph_process_new_functions (void)
383 struct cgraph_node *node;
385 varpool_analyze_pending_decls ();
386 /* Note that this queue may grow as its being processed, as the new
387 functions may generate new ones. */
388 while (cgraph_new_nodes)
390 node = cgraph_new_nodes;
392 cgraph_new_nodes = cgraph_new_nodes->next_needed;
393 switch (cgraph_state)
395 case CGRAPH_STATE_CONSTRUCTION:
396 /* At construction time we just need to finalize function and move
397 it into reachable functions list. */
399 node->next_needed = NULL;
400 cgraph_finalize_function (fndecl, false);
401 cgraph_mark_reachable_node (node);
405 case CGRAPH_STATE_IPA:
406 case CGRAPH_STATE_IPA_SSA:
407 /* When IPA optimization already started, do all essential
408 transformations that has been already performed on the whole
409 cgraph but not on this function. */
411 gimple_register_cfg_hooks ();
413 cgraph_analyze_function (node);
414 push_cfun (DECL_STRUCT_FUNCTION (fndecl));
415 current_function_decl = fndecl;
416 compute_inline_parameters (node);
417 if ((cgraph_state == CGRAPH_STATE_IPA_SSA
418 && !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (fndecl)))
419 /* When not optimizing, be sure we run early local passes anyway
422 execute_pass_list (pass_early_local_passes.pass.sub);
423 free_dominance_info (CDI_POST_DOMINATORS);
424 free_dominance_info (CDI_DOMINATORS);
426 current_function_decl = NULL;
429 case CGRAPH_STATE_EXPANSION:
430 /* Functions created during expansion shall be compiled
433 cgraph_expand_function (node);
440 cgraph_call_function_insertion_hooks (node);
441 varpool_analyze_pending_decls ();
446 /* As an GCC extension we allow redefinition of the function. The
447 semantics when both copies of bodies differ is not well defined.
448 We replace the old body with new body so in unit at a time mode
449 we always use new body, while in normal mode we may end up with
450 old body inlined into some functions and new body expanded and
453 ??? It may make more sense to use one body for inlining and other
454 body for expanding the function but this is difficult to do. */
457 cgraph_reset_node (struct cgraph_node *node)
459 /* If node->process is set, then we have already begun whole-unit analysis.
460 This is *not* testing for whether we've already emitted the function.
461 That case can be sort-of legitimately seen with real function redefinition
462 errors. I would argue that the front end should never present us with
463 such a case, but don't enforce that for now. */
464 gcc_assert (!node->process);
466 /* Reset our data structures so we can analyze the function again. */
467 memset (&node->local, 0, sizeof (node->local));
468 memset (&node->global, 0, sizeof (node->global));
469 memset (&node->rtl, 0, sizeof (node->rtl));
470 node->analyzed = false;
471 node->local.redefined_extern_inline = true;
472 node->local.finalized = false;
474 cgraph_node_remove_callees (node);
476 /* We may need to re-queue the node for assembling in case
477 we already proceeded it and ignored as not needed or got
478 a re-declaration in IMA mode. */
481 struct cgraph_node *n;
483 for (n = cgraph_nodes_queue; n; n = n->next_needed)
492 cgraph_lower_function (struct cgraph_node *node)
498 lower_nested_functions (node->decl);
499 gcc_assert (!node->nested);
501 tree_lowering_passes (node->decl);
502 node->lowered = true;
505 /* DECL has been parsed. Take it, queue it, compile it at the whim of the
506 logic in effect. If NESTED is true, then our caller cannot stand to have
507 the garbage collector run at the moment. We would need to either create
508 a new GC context, or just not compile right now. */
511 cgraph_finalize_function (tree decl, bool nested)
513 struct cgraph_node *node = cgraph_node (decl);
515 if (node->local.finalized)
516 cgraph_reset_node (node);
518 node->pid = cgraph_max_pid ++;
519 notice_global_symbol (decl);
520 node->local.finalized = true;
521 node->lowered = DECL_STRUCT_FUNCTION (decl)->cfg != NULL;
522 node->finalized_by_frontend = true;
523 record_cdtor_fn (node->decl);
525 if (cgraph_decide_is_function_needed (node, decl))
526 cgraph_mark_needed_node (node);
528 /* Since we reclaim unreachable nodes at the end of every language
529 level unit, we need to be conservative about possible entry points
531 if ((TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl)))
532 cgraph_mark_reachable_node (node);
534 /* If we've not yet emitted decl, tell the debug info about it. */
535 if (!TREE_ASM_WRITTEN (decl))
536 (*debug_hooks->deferred_inline_function) (decl);
538 /* Possibly warn about unused parameters. */
539 if (warn_unused_parameter)
540 do_warn_unused_parameter (decl);
546 /* C99 extern inline keywords allow changing of declaration after function
547 has been finalized. We need to re-decide if we want to mark the function as
551 cgraph_mark_if_needed (tree decl)
553 struct cgraph_node *node = cgraph_node (decl);
554 if (node->local.finalized && cgraph_decide_is_function_needed (node, decl))
555 cgraph_mark_needed_node (node);
558 /* Return TRUE if NODE2 is equivalent to NODE or its clone. */
560 clone_of_p (struct cgraph_node *node, struct cgraph_node *node2)
562 while (node != node2 && node2)
563 node2 = node2->clone_of;
564 return node2 != NULL;
567 /* Verify cgraph nodes of given cgraph node. */
569 verify_cgraph_node (struct cgraph_node *node)
571 struct cgraph_edge *e;
572 struct function *this_cfun = DECL_STRUCT_FUNCTION (node->decl);
573 struct function *saved_cfun = cfun;
574 basic_block this_block;
575 gimple_stmt_iterator gsi;
576 bool error_found = false;
578 if (errorcount || sorrycount)
581 timevar_push (TV_CGRAPH_VERIFY);
582 /* debug_generic_stmt needs correct cfun */
583 set_cfun (this_cfun);
584 for (e = node->callees; e; e = e->next_callee)
587 error ("aux field set for edge %s->%s",
588 identifier_to_locale (cgraph_node_name (e->caller)),
589 identifier_to_locale (cgraph_node_name (e->callee)));
594 error ("Execution count is negative");
597 if (node->global.inlined_to && node->local.externally_visible)
599 error ("Externally visible inline clone");
602 if (node->global.inlined_to && node->address_taken)
604 error ("Inline clone with address taken");
607 if (node->global.inlined_to && node->needed)
609 error ("Inline clone is needed");
612 for (e = node->indirect_calls; e; e = e->next_callee)
616 error ("aux field set for indirect edge from %s",
617 identifier_to_locale (cgraph_node_name (e->caller)));
620 if (!e->indirect_unknown_callee
621 || !e->indirect_info)
623 error ("An indirect edge from %s is not marked as indirect or has "
624 "associated indirect_info, the corresponding statement is: ",
625 identifier_to_locale (cgraph_node_name (e->caller)));
626 debug_gimple_stmt (e->call_stmt);
630 for (e = node->callers; e; e = e->next_caller)
634 error ("caller edge count is negative");
637 if (e->frequency < 0)
639 error ("caller edge frequency is negative");
642 if (e->frequency > CGRAPH_FREQ_MAX)
644 error ("caller edge frequency is too large");
647 if (gimple_has_body_p (e->caller->decl)
648 && !e->caller->global.inlined_to
650 != compute_call_stmt_bb_frequency (e->caller->decl,
651 gimple_bb (e->call_stmt))))
653 error ("caller edge frequency %i does not match BB freqency %i",
655 compute_call_stmt_bb_frequency (e->caller->decl,
656 gimple_bb (e->call_stmt)));
659 if (!e->inline_failed)
661 if (node->global.inlined_to
662 != (e->caller->global.inlined_to
663 ? e->caller->global.inlined_to : e->caller))
665 error ("inlined_to pointer is wrong");
668 if (node->callers->next_caller)
670 error ("multiple inline callers");
675 if (node->global.inlined_to)
677 error ("inlined_to pointer set for noninline callers");
681 if (!node->callers && node->global.inlined_to)
683 error ("inlined_to pointer is set but no predecessors found");
686 if (node->global.inlined_to == node)
688 error ("inlined_to pointer refers to itself");
692 if (!cgraph_node (node->decl))
694 error ("node not found in cgraph_hash");
700 struct cgraph_node *n;
701 for (n = node->clone_of->clones; n; n = n->next_sibling_clone)
706 error ("node has wrong clone_of");
712 struct cgraph_node *n;
713 for (n = node->clones; n; n = n->next_sibling_clone)
714 if (n->clone_of != node)
718 error ("node has wrong clone list");
722 if ((node->prev_sibling_clone || node->next_sibling_clone) && !node->clone_of)
724 error ("node is in clone list but it is not clone");
727 if (!node->prev_sibling_clone && node->clone_of && node->clone_of->clones != node)
729 error ("node has wrong prev_clone pointer");
732 if (node->prev_sibling_clone && node->prev_sibling_clone->next_sibling_clone != node)
734 error ("double linked list of clones corrupted");
737 if (node->same_comdat_group)
739 struct cgraph_node *n = node->same_comdat_group;
741 if (!DECL_ONE_ONLY (node->decl))
743 error ("non-DECL_ONE_ONLY node in a same_comdat_group list");
748 error ("node is alone in a comdat group");
753 if (!n->same_comdat_group)
755 error ("same_comdat_group is not a circular list");
759 n = n->same_comdat_group;
764 if (node->analyzed && gimple_has_body_p (node->decl)
765 && !TREE_ASM_WRITTEN (node->decl)
766 && (!DECL_EXTERNAL (node->decl) || node->global.inlined_to)
771 /* The nodes we're interested in are never shared, so walk
772 the tree ignoring duplicates. */
773 struct pointer_set_t *visited_nodes = pointer_set_create ();
774 /* Reach the trees by walking over the CFG, and note the
775 enclosing basic-blocks in the call edges. */
776 FOR_EACH_BB_FN (this_block, this_cfun)
777 for (gsi = gsi_start_bb (this_block);
781 gimple stmt = gsi_stmt (gsi);
782 if (is_gimple_call (stmt))
784 struct cgraph_edge *e = cgraph_edge (node, stmt);
785 tree decl = gimple_call_fndecl (stmt);
790 error ("shared call_stmt:");
791 debug_gimple_stmt (stmt);
794 if (!e->indirect_unknown_callee)
796 if (e->callee->same_body_alias)
798 error ("edge points to same body alias:");
799 debug_tree (e->callee->decl);
802 else if (!node->global.inlined_to
803 && !e->callee->global.inlined_to
805 && !clone_of_p (cgraph_node (decl),
808 error ("edge points to wrong declaration:");
809 debug_tree (e->callee->decl);
810 fprintf (stderr," Instead of:");
815 else if (!node->global.inlined_to
816 && !e->callee->global.inlined_to
817 && !clone_of_p (cgraph_node (decl), e->callee))
819 error ("an indirect edge with unknown callee "
820 "corresponding to a call_stmt with "
821 "a known declaration:");
823 debug_gimple_stmt (e->call_stmt);
829 error ("missing callgraph edge for call stmt:");
830 debug_gimple_stmt (stmt);
835 pointer_set_destroy (visited_nodes);
838 /* No CFG available?! */
841 for (e = node->callees; e; e = e->next_callee)
845 error ("edge %s->%s has no corresponding call_stmt",
846 identifier_to_locale (cgraph_node_name (e->caller)),
847 identifier_to_locale (cgraph_node_name (e->callee)));
848 debug_gimple_stmt (e->call_stmt);
853 for (e = node->indirect_calls; e; e = e->next_callee)
857 error ("an indirect edge from %s has no corresponding call_stmt",
858 identifier_to_locale (cgraph_node_name (e->caller)));
859 debug_gimple_stmt (e->call_stmt);
867 dump_cgraph_node (stderr, node);
868 internal_error ("verify_cgraph_node failed");
870 set_cfun (saved_cfun);
871 timevar_pop (TV_CGRAPH_VERIFY);
874 /* Verify whole cgraph structure. */
878 struct cgraph_node *node;
880 if (sorrycount || errorcount)
883 for (node = cgraph_nodes; node; node = node->next)
884 verify_cgraph_node (node);
887 /* Output all asm statements we have stored up to be output. */
890 cgraph_output_pending_asms (void)
892 struct cgraph_asm_node *can;
894 if (errorcount || sorrycount)
897 for (can = cgraph_asm_nodes; can; can = can->next)
898 assemble_asm (can->asm_str);
899 cgraph_asm_nodes = NULL;
902 /* Analyze the function scheduled to be output. */
904 cgraph_analyze_function (struct cgraph_node *node)
906 tree save = current_function_decl;
907 tree decl = node->decl;
909 current_function_decl = decl;
910 push_cfun (DECL_STRUCT_FUNCTION (decl));
912 assign_assembler_name_if_neeeded (node->decl);
914 /* Make sure to gimplify bodies only once. During analyzing a
915 function we lower it, which will require gimplified nested
916 functions, so we can end up here with an already gimplified
918 if (!gimple_body (decl))
919 gimplify_function_tree (decl);
920 dump_function (TDI_generic, decl);
922 cgraph_lower_function (node);
923 node->analyzed = true;
926 current_function_decl = save;
929 /* Look for externally_visible and used attributes and mark cgraph nodes
932 We cannot mark the nodes at the point the attributes are processed (in
933 handle_*_attribute) because the copy of the declarations available at that
934 point may not be canonical. For example, in:
937 void f() __attribute__((used));
939 the declaration we see in handle_used_attribute will be the second
940 declaration -- but the front end will subsequently merge that declaration
941 with the original declaration and discard the second declaration.
943 Furthermore, we can't mark these nodes in cgraph_finalize_function because:
946 void f() __attribute__((externally_visible));
950 So, we walk the nodes at the end of the translation unit, applying the
951 attributes at that point. */
954 process_function_and_variable_attributes (struct cgraph_node *first,
955 struct varpool_node *first_var)
957 struct cgraph_node *node;
958 struct varpool_node *vnode;
960 for (node = cgraph_nodes; node != first; node = node->next)
962 tree decl = node->decl;
963 if (DECL_PRESERVE_P (decl))
964 cgraph_mark_needed_node (node);
965 if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
967 if (! TREE_PUBLIC (node->decl))
968 warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes,
969 "%<externally_visible%>"
970 " attribute have effect only on public objects");
971 else if (node->local.finalized)
972 cgraph_mark_needed_node (node);
975 for (vnode = varpool_nodes; vnode != first_var; vnode = vnode->next)
977 tree decl = vnode->decl;
978 if (DECL_PRESERVE_P (decl))
980 vnode->force_output = true;
981 if (vnode->finalized)
982 varpool_mark_needed_node (vnode);
984 if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
986 if (! TREE_PUBLIC (vnode->decl))
987 warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes,
988 "%<externally_visible%>"
989 " attribute have effect only on public objects");
990 else if (vnode->finalized)
991 varpool_mark_needed_node (vnode);
996 /* Process CGRAPH_NODES_NEEDED queue, analyze each function (and transitively
997 each reachable functions) and build cgraph.
998 The function can be called multiple times after inserting new nodes
999 into beginning of queue. Just the new part of queue is re-scanned then. */
1002 cgraph_analyze_functions (void)
1004 /* Keep track of already processed nodes when called multiple times for
1005 intermodule optimization. */
1006 static struct cgraph_node *first_analyzed;
1007 struct cgraph_node *first_processed = first_analyzed;
1008 static struct varpool_node *first_analyzed_var;
1009 struct cgraph_node *node, *next;
1011 process_function_and_variable_attributes (first_processed,
1012 first_analyzed_var);
1013 first_processed = cgraph_nodes;
1014 first_analyzed_var = varpool_nodes;
1015 varpool_analyze_pending_decls ();
1016 if (cgraph_dump_file)
1018 fprintf (cgraph_dump_file, "Initial entry points:");
1019 for (node = cgraph_nodes; node != first_analyzed; node = node->next)
1021 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1022 fprintf (cgraph_dump_file, "\n");
1024 cgraph_process_new_functions ();
1026 /* Propagate reachability flag and lower representation of all reachable
1027 functions. In the future, lowering will introduce new functions and
1028 new entry points on the way (by template instantiation and virtual
1029 method table generation for instance). */
1030 while (cgraph_nodes_queue)
1032 struct cgraph_edge *edge;
1033 tree decl = cgraph_nodes_queue->decl;
1035 node = cgraph_nodes_queue;
1036 cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
1037 node->next_needed = NULL;
1039 /* ??? It is possible to create extern inline function and later using
1040 weak alias attribute to kill its body. See
1041 gcc.c-torture/compile/20011119-1.c */
1042 if (!DECL_STRUCT_FUNCTION (decl))
1044 cgraph_reset_node (node);
1048 if (!node->analyzed)
1049 cgraph_analyze_function (node);
1051 for (edge = node->callees; edge; edge = edge->next_callee)
1052 if (!edge->callee->reachable)
1053 cgraph_mark_reachable_node (edge->callee);
1055 if (node->same_comdat_group)
1057 for (next = node->same_comdat_group;
1059 next = next->same_comdat_group)
1060 cgraph_mark_reachable_node (next);
1063 /* If decl is a clone of an abstract function, mark that abstract
1064 function so that we don't release its body. The DECL_INITIAL() of that
1065 abstract function declaration will be later needed to output debug info. */
1066 if (DECL_ABSTRACT_ORIGIN (decl))
1068 struct cgraph_node *origin_node = cgraph_node (DECL_ABSTRACT_ORIGIN (decl));
1069 origin_node->abstract_and_needed = true;
1072 /* We finalize local static variables during constructing callgraph
1073 edges. Process their attributes too. */
1074 process_function_and_variable_attributes (first_processed,
1075 first_analyzed_var);
1076 first_processed = cgraph_nodes;
1077 first_analyzed_var = varpool_nodes;
1078 varpool_analyze_pending_decls ();
1079 cgraph_process_new_functions ();
1082 /* Collect entry points to the unit. */
1083 if (cgraph_dump_file)
1085 fprintf (cgraph_dump_file, "Unit entry points:");
1086 for (node = cgraph_nodes; node != first_analyzed; node = node->next)
1088 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1089 fprintf (cgraph_dump_file, "\n\nInitial ");
1090 dump_cgraph (cgraph_dump_file);
1093 if (cgraph_dump_file)
1094 fprintf (cgraph_dump_file, "\nReclaiming functions:");
1096 for (node = cgraph_nodes; node != first_analyzed; node = next)
1098 tree decl = node->decl;
1101 if (node->local.finalized && !gimple_has_body_p (decl))
1102 cgraph_reset_node (node);
1104 if (!node->reachable && gimple_has_body_p (decl))
1106 if (cgraph_dump_file)
1107 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1108 cgraph_remove_node (node);
1112 node->next_needed = NULL;
1113 gcc_assert (!node->local.finalized || gimple_has_body_p (decl));
1114 gcc_assert (node->analyzed == node->local.finalized);
1116 if (cgraph_dump_file)
1118 fprintf (cgraph_dump_file, "\n\nReclaimed ");
1119 dump_cgraph (cgraph_dump_file);
1121 first_analyzed = cgraph_nodes;
1126 /* Analyze the whole compilation unit once it is parsed completely. */
1129 cgraph_finalize_compilation_unit (void)
1131 timevar_push (TV_CGRAPH);
1133 /* Do not skip analyzing the functions if there were errors, we
1134 miss diagnostics for following functions otherwise. */
1136 /* Emit size functions we didn't inline. */
1137 finalize_size_functions ();
1139 /* Call functions declared with the "constructor" or "destructor"
1141 cgraph_build_cdtor_fns ();
1143 /* Mark alias targets necessary and emit diagnostics. */
1144 finish_aliases_1 ();
1148 fprintf (stderr, "\nAnalyzing compilation unit\n");
1152 /* Gimplify and lower all functions, compute reachability and
1153 remove unreachable nodes. */
1154 cgraph_analyze_functions ();
1156 /* Mark alias targets necessary and emit diagnostics. */
1157 finish_aliases_1 ();
1159 /* Gimplify and lower thunks. */
1160 cgraph_analyze_functions ();
1162 /* Finally drive the pass manager. */
1165 timevar_pop (TV_CGRAPH);
1169 /* Figure out what functions we want to assemble. */
1172 cgraph_mark_functions_to_output (void)
1174 struct cgraph_node *node;
1175 #ifdef ENABLE_CHECKING
1176 bool check_same_comdat_groups = false;
1178 for (node = cgraph_nodes; node; node = node->next)
1179 gcc_assert (!node->process);
1182 for (node = cgraph_nodes; node; node = node->next)
1184 tree decl = node->decl;
1185 struct cgraph_edge *e;
1187 gcc_assert (!node->process || node->same_comdat_group);
1191 for (e = node->callers; e; e = e->next_caller)
1192 if (e->inline_failed)
1195 /* We need to output all local functions that are used and not
1196 always inlined, as well as those that are reachable from
1197 outside the current compilation unit. */
1199 && !node->global.inlined_to
1200 && (node->needed || node->reachable_from_other_partition
1201 || node->address_taken
1202 || (e && node->reachable))
1203 && !TREE_ASM_WRITTEN (decl)
1204 && !DECL_EXTERNAL (decl))
1207 if (node->same_comdat_group)
1209 struct cgraph_node *next;
1210 for (next = node->same_comdat_group;
1212 next = next->same_comdat_group)
1216 else if (node->same_comdat_group)
1218 #ifdef ENABLE_CHECKING
1219 check_same_comdat_groups = true;
1224 /* We should've reclaimed all functions that are not needed. */
1225 #ifdef ENABLE_CHECKING
1226 if (!node->global.inlined_to
1227 && gimple_has_body_p (decl)
1228 /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
1229 are inside partition, we can end up not removing the body since we no longer
1230 have analyzed node pointing to it. */
1231 && !node->in_other_partition
1232 && !DECL_EXTERNAL (decl))
1234 dump_cgraph_node (stderr, node);
1235 internal_error ("failed to reclaim unneeded function");
1238 gcc_assert (node->global.inlined_to
1239 || !gimple_has_body_p (decl)
1240 || node->in_other_partition
1241 || DECL_EXTERNAL (decl));
1246 #ifdef ENABLE_CHECKING
1247 if (check_same_comdat_groups)
1248 for (node = cgraph_nodes; node; node = node->next)
1249 if (node->same_comdat_group && !node->process)
1251 tree decl = node->decl;
1252 if (!node->global.inlined_to
1253 && gimple_has_body_p (decl)
1254 /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
1255 are inside partition, we can end up not removing the body since we no longer
1256 have analyzed node pointing to it. */
1257 && !node->in_other_partition
1258 && !DECL_EXTERNAL (decl))
1260 dump_cgraph_node (stderr, node);
1261 internal_error ("failed to reclaim unneeded function");
1267 /* DECL is FUNCTION_DECL. Initialize datastructures so DECL is a function
1268 in lowered gimple form.
1270 Set current_function_decl and cfun to newly constructed empty function body.
1271 return basic block in the function body. */
1274 init_lowered_empty_function (tree decl)
1278 current_function_decl = decl;
1279 allocate_struct_function (decl, false);
1280 gimple_register_cfg_hooks ();
1281 init_empty_tree_cfg ();
1282 init_tree_ssa (cfun);
1283 init_ssa_operands ();
1284 cfun->gimple_df->in_ssa_p = true;
1285 DECL_INITIAL (decl) = make_node (BLOCK);
1287 DECL_SAVED_TREE (decl) = error_mark_node;
1288 cfun->curr_properties |=
1289 (PROP_gimple_lcf | PROP_gimple_leh | PROP_cfg | PROP_referenced_vars |
1292 /* Create BB for body of the function and connect it properly. */
1293 bb = create_basic_block (NULL, (void *) 0, ENTRY_BLOCK_PTR);
1294 make_edge (ENTRY_BLOCK_PTR, bb, 0);
1295 make_edge (bb, EXIT_BLOCK_PTR, 0);
1300 /* Adjust PTR by the constant FIXED_OFFSET, and by the vtable
1301 offset indicated by VIRTUAL_OFFSET, if that is
1302 non-null. THIS_ADJUSTING is nonzero for a this adjusting thunk and
1303 zero for a result adjusting thunk. */
1306 thunk_adjust (gimple_stmt_iterator * bsi,
1307 tree ptr, bool this_adjusting,
1308 HOST_WIDE_INT fixed_offset, tree virtual_offset)
1314 && fixed_offset != 0)
1316 stmt = gimple_build_assign (ptr,
1317 fold_build2_loc (input_location,
1319 TREE_TYPE (ptr), ptr,
1320 size_int (fixed_offset)));
1321 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1324 /* If there's a virtual offset, look up that value in the vtable and
1325 adjust the pointer again. */
1333 if (!vtable_entry_type)
1335 tree vfunc_type = make_node (FUNCTION_TYPE);
1336 TREE_TYPE (vfunc_type) = integer_type_node;
1337 TYPE_ARG_TYPES (vfunc_type) = NULL_TREE;
1338 layout_type (vfunc_type);
1340 vtable_entry_type = build_pointer_type (vfunc_type);
1344 create_tmp_var (build_pointer_type
1345 (build_pointer_type (vtable_entry_type)), "vptr");
1347 /* The vptr is always at offset zero in the object. */
1348 stmt = gimple_build_assign (vtabletmp,
1349 build1 (NOP_EXPR, TREE_TYPE (vtabletmp),
1351 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1352 mark_symbols_for_renaming (stmt);
1353 find_referenced_vars_in (stmt);
1355 /* Form the vtable address. */
1356 vtabletmp2 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp)),
1358 stmt = gimple_build_assign (vtabletmp2,
1359 build1 (INDIRECT_REF,
1360 TREE_TYPE (vtabletmp2), vtabletmp));
1361 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1362 mark_symbols_for_renaming (stmt);
1363 find_referenced_vars_in (stmt);
1365 /* Find the entry with the vcall offset. */
1366 stmt = gimple_build_assign (vtabletmp2,
1367 fold_build2_loc (input_location,
1369 TREE_TYPE (vtabletmp2),
1371 fold_convert (sizetype,
1373 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1375 /* Get the offset itself. */
1376 vtabletmp3 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp2)),
1378 stmt = gimple_build_assign (vtabletmp3,
1379 build1 (INDIRECT_REF,
1380 TREE_TYPE (vtabletmp3),
1382 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1383 mark_symbols_for_renaming (stmt);
1384 find_referenced_vars_in (stmt);
1386 /* Cast to sizetype. */
1387 offsettmp = create_tmp_var (sizetype, "offset");
1388 stmt = gimple_build_assign (offsettmp, fold_convert (sizetype, vtabletmp3));
1389 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1390 mark_symbols_for_renaming (stmt);
1391 find_referenced_vars_in (stmt);
1393 /* Adjust the `this' pointer. */
1394 ptr = fold_build2_loc (input_location,
1395 POINTER_PLUS_EXPR, TREE_TYPE (ptr), ptr,
1400 && fixed_offset != 0)
1401 /* Adjust the pointer by the constant. */
1405 if (TREE_CODE (ptr) == VAR_DECL)
1409 ptrtmp = create_tmp_var (TREE_TYPE (ptr), "ptr");
1410 stmt = gimple_build_assign (ptrtmp, ptr);
1411 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1412 mark_symbols_for_renaming (stmt);
1413 find_referenced_vars_in (stmt);
1415 ptr = fold_build2_loc (input_location,
1416 POINTER_PLUS_EXPR, TREE_TYPE (ptrtmp), ptrtmp,
1417 size_int (fixed_offset));
1420 /* Emit the statement and gimplify the adjustment expression. */
1421 ret = create_tmp_var (TREE_TYPE (ptr), "adjusted_this");
1422 stmt = gimple_build_assign (ret, ptr);
1423 mark_symbols_for_renaming (stmt);
1424 find_referenced_vars_in (stmt);
1425 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1430 /* Produce assembler for thunk NODE. */
1433 assemble_thunk (struct cgraph_node *node)
1435 bool this_adjusting = node->thunk.this_adjusting;
1436 HOST_WIDE_INT fixed_offset = node->thunk.fixed_offset;
1437 HOST_WIDE_INT virtual_value = node->thunk.virtual_value;
1438 tree virtual_offset = NULL;
1439 tree alias = node->thunk.alias;
1440 tree thunk_fndecl = node->decl;
1441 tree a = DECL_ARGUMENTS (thunk_fndecl);
1443 current_function_decl = thunk_fndecl;
1446 && targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset,
1447 virtual_value, alias))
1452 DECL_RESULT (thunk_fndecl)
1453 = build_decl (DECL_SOURCE_LOCATION (thunk_fndecl),
1454 RESULT_DECL, 0, integer_type_node);
1455 fnname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk_fndecl));
1457 /* The back end expects DECL_INITIAL to contain a BLOCK, so we
1459 fn_block = make_node (BLOCK);
1460 BLOCK_VARS (fn_block) = a;
1461 DECL_INITIAL (thunk_fndecl) = fn_block;
1462 init_function_start (thunk_fndecl);
1464 assemble_start_function (thunk_fndecl, fnname);
1466 targetm.asm_out.output_mi_thunk (asm_out_file, thunk_fndecl,
1467 fixed_offset, virtual_value, alias);
1469 assemble_end_function (thunk_fndecl, fnname);
1470 init_insn_lengths ();
1471 free_after_compilation (cfun);
1473 TREE_ASM_WRITTEN (thunk_fndecl) = 1;
1478 basic_block bb, then_bb, else_bb, return_bb;
1479 gimple_stmt_iterator bsi;
1485 VEC(tree, heap) *vargs;
1490 DECL_IGNORED_P (thunk_fndecl) = 1;
1491 bitmap_obstack_initialize (NULL);
1493 if (node->thunk.virtual_offset_p)
1494 virtual_offset = size_int (virtual_value);
1496 /* Build the return declaration for the function. */
1497 restype = TREE_TYPE (TREE_TYPE (thunk_fndecl));
1498 if (DECL_RESULT (thunk_fndecl) == NULL_TREE)
1500 resdecl = build_decl (input_location, RESULT_DECL, 0, restype);
1501 DECL_ARTIFICIAL (resdecl) = 1;
1502 DECL_IGNORED_P (resdecl) = 1;
1503 DECL_RESULT (thunk_fndecl) = resdecl;
1506 resdecl = DECL_RESULT (thunk_fndecl);
1508 bb = then_bb = else_bb = return_bb = init_lowered_empty_function (thunk_fndecl);
1510 bsi = gsi_start_bb (bb);
1512 /* Build call to the function being thunked. */
1513 if (!VOID_TYPE_P (restype))
1515 if (!is_gimple_reg_type (restype))
1518 cfun->local_decls = tree_cons (NULL_TREE, restmp, cfun->local_decls);
1519 BLOCK_VARS (DECL_INITIAL (current_function_decl)) = restmp;
1522 restmp = create_tmp_var_raw (restype, "retval");
1525 for (arg = a; arg; arg = TREE_CHAIN (arg))
1527 vargs = VEC_alloc (tree, heap, nargs);
1529 VEC_quick_push (tree, vargs,
1534 VEC_quick_push (tree, vargs, a);
1535 for (i = 1, arg = TREE_CHAIN (a); i < nargs; i++, arg = TREE_CHAIN (arg))
1536 VEC_quick_push (tree, vargs, arg);
1537 call = gimple_build_call_vec (build_fold_addr_expr_loc (0, alias), vargs);
1538 VEC_free (tree, heap, vargs);
1539 gimple_call_set_cannot_inline (call, true);
1540 gimple_call_set_from_thunk (call, true);
1542 gimple_call_set_lhs (call, restmp);
1543 gsi_insert_after (&bsi, call, GSI_NEW_STMT);
1544 mark_symbols_for_renaming (call);
1545 find_referenced_vars_in (call);
1548 if (restmp && !this_adjusting)
1550 tree true_label = NULL_TREE;
1552 if (TREE_CODE (TREE_TYPE (restmp)) == POINTER_TYPE)
1555 /* If the return type is a pointer, we need to
1556 protect against NULL. We know there will be an
1557 adjustment, because that's why we're emitting a
1559 then_bb = create_basic_block (NULL, (void *) 0, bb);
1560 return_bb = create_basic_block (NULL, (void *) 0, then_bb);
1561 else_bb = create_basic_block (NULL, (void *) 0, else_bb);
1562 remove_edge (single_succ_edge (bb));
1563 true_label = gimple_block_label (then_bb);
1564 stmt = gimple_build_cond (NE_EXPR, restmp,
1565 fold_convert (TREE_TYPE (restmp),
1567 NULL_TREE, NULL_TREE);
1568 gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
1569 make_edge (bb, then_bb, EDGE_TRUE_VALUE);
1570 make_edge (bb, else_bb, EDGE_FALSE_VALUE);
1571 make_edge (return_bb, EXIT_BLOCK_PTR, 0);
1572 make_edge (then_bb, return_bb, EDGE_FALLTHRU);
1573 make_edge (else_bb, return_bb, EDGE_FALLTHRU);
1574 bsi = gsi_last_bb (then_bb);
1577 restmp = thunk_adjust (&bsi, restmp, /*this_adjusting=*/0,
1578 fixed_offset, virtual_offset);
1582 bsi = gsi_last_bb (else_bb);
1583 stmt = gimple_build_assign (restmp, fold_convert (TREE_TYPE (restmp),
1584 integer_zero_node));
1585 gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
1586 bsi = gsi_last_bb (return_bb);
1590 gimple_call_set_tail (call, true);
1592 /* Build return value. */
1593 ret = gimple_build_return (restmp);
1594 gsi_insert_after (&bsi, ret, GSI_NEW_STMT);
1596 delete_unreachable_blocks ();
1597 update_ssa (TODO_update_ssa);
1599 cgraph_remove_same_body_alias (node);
1600 /* Since we want to emit the thunk, we explicitly mark its name as
1602 cgraph_add_new_function (thunk_fndecl, true);
1603 bitmap_obstack_release (NULL);
1605 current_function_decl = NULL;
1608 /* Expand function specified by NODE. */
1611 cgraph_expand_function (struct cgraph_node *node)
1613 tree decl = node->decl;
1615 /* We ought to not compile any inline clones. */
1616 gcc_assert (!node->global.inlined_to);
1618 announce_function (decl);
1621 gcc_assert (node->lowered);
1623 /* Generate RTL for the body of DECL. */
1624 tree_rest_of_compilation (decl);
1626 /* Make sure that BE didn't give up on compiling. */
1627 gcc_assert (TREE_ASM_WRITTEN (decl));
1628 current_function_decl = NULL;
1629 if (node->same_body)
1631 struct cgraph_node *alias, *next;
1632 bool saved_alias = node->alias;
1633 for (alias = node->same_body;
1634 alias && alias->next; alias = alias->next)
1636 /* Walk aliases in the order they were created; it is possible that
1637 thunks reffers to the aliases made earlier. */
1638 for (; alias; alias = next)
1640 next = alias->previous;
1641 if (!alias->thunk.thunk_p)
1642 assemble_alias (alias->decl,
1643 DECL_ASSEMBLER_NAME (alias->thunk.alias));
1645 assemble_thunk (alias);
1647 node->alias = saved_alias;
1649 gcc_assert (!cgraph_preserve_function_body_p (decl));
1650 cgraph_release_function_body (node);
1651 /* Eliminate all call edges. This is important so the GIMPLE_CALL no longer
1652 points to the dead function body. */
1653 cgraph_node_remove_callees (node);
1655 cgraph_function_flags_ready = true;
1658 /* Return true when CALLER_DECL should be inlined into CALLEE_DECL. */
1661 cgraph_inline_p (struct cgraph_edge *e, cgraph_inline_failed_t *reason)
1663 *reason = e->inline_failed;
1664 return !e->inline_failed;
1669 /* Expand all functions that must be output.
1671 Attempt to topologically sort the nodes so function is output when
1672 all called functions are already assembled to allow data to be
1673 propagated across the callgraph. Use a stack to get smaller distance
1674 between a function and its callees (later we may choose to use a more
1675 sophisticated algorithm for function reordering; we will likely want
1676 to use subsections to make the output functions appear in top-down
1680 cgraph_expand_all_functions (void)
1682 struct cgraph_node *node;
1683 struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
1684 int order_pos, new_order_pos = 0;
1687 order_pos = cgraph_postorder (order);
1688 gcc_assert (order_pos == cgraph_n_nodes);
1690 /* Garbage collector may remove inline clones we eliminate during
1691 optimization. So we must be sure to not reference them. */
1692 for (i = 0; i < order_pos; i++)
1693 if (order[i]->process)
1694 order[new_order_pos++] = order[i];
1696 for (i = new_order_pos - 1; i >= 0; i--)
1701 gcc_assert (node->reachable);
1703 cgraph_expand_function (node);
1706 cgraph_process_new_functions ();
1712 /* This is used to sort the node types by the cgraph order number. */
1714 enum cgraph_order_sort_kind
1716 ORDER_UNDEFINED = 0,
1722 struct cgraph_order_sort
1724 enum cgraph_order_sort_kind kind;
1727 struct cgraph_node *f;
1728 struct varpool_node *v;
1729 struct cgraph_asm_node *a;
1733 /* Output all functions, variables, and asm statements in the order
1734 according to their order fields, which is the order in which they
1735 appeared in the file. This implements -fno-toplevel-reorder. In
1736 this mode we may output functions and variables which don't really
1737 need to be output. */
1740 cgraph_output_in_order (void)
1743 struct cgraph_order_sort *nodes;
1745 struct cgraph_node *pf;
1746 struct varpool_node *pv;
1747 struct cgraph_asm_node *pa;
1750 nodes = XCNEWVEC (struct cgraph_order_sort, max);
1752 varpool_analyze_pending_decls ();
1754 for (pf = cgraph_nodes; pf; pf = pf->next)
1759 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1760 nodes[i].kind = ORDER_FUNCTION;
1765 for (pv = varpool_nodes_queue; pv; pv = pv->next_needed)
1768 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1769 nodes[i].kind = ORDER_VAR;
1773 for (pa = cgraph_asm_nodes; pa; pa = pa->next)
1776 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1777 nodes[i].kind = ORDER_ASM;
1781 /* In toplevel reorder mode we output all statics; mark them as needed. */
1782 for (i = 0; i < max; ++i)
1784 if (nodes[i].kind == ORDER_VAR)
1786 varpool_mark_needed_node (nodes[i].u.v);
1789 varpool_empty_needed_queue ();
1791 for (i = 0; i < max; ++i)
1793 switch (nodes[i].kind)
1795 case ORDER_FUNCTION:
1796 nodes[i].u.f->process = 0;
1797 cgraph_expand_function (nodes[i].u.f);
1801 varpool_assemble_decl (nodes[i].u.v);
1805 assemble_asm (nodes[i].u.a->asm_str);
1808 case ORDER_UNDEFINED:
1816 cgraph_asm_nodes = NULL;
1820 /* Return true when function body of DECL still needs to be kept around
1821 for later re-use. */
1823 cgraph_preserve_function_body_p (tree decl)
1825 struct cgraph_node *node;
1827 gcc_assert (cgraph_global_info_ready);
1828 /* Look if there is any clone around. */
1829 node = cgraph_node (decl);
1839 current_function_decl = NULL;
1840 gimple_register_cfg_hooks ();
1841 bitmap_obstack_initialize (NULL);
1843 invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_START, NULL);
1846 execute_ipa_pass_list (all_small_ipa_passes);
1848 /* If pass_all_early_optimizations was not scheduled, the state of
1849 the cgraph will not be properly updated. Update it now. */
1850 if (cgraph_state < CGRAPH_STATE_IPA_SSA)
1851 cgraph_state = CGRAPH_STATE_IPA_SSA;
1855 /* Generate coverage variables and constructors. */
1858 /* Process new functions added. */
1860 current_function_decl = NULL;
1861 cgraph_process_new_functions ();
1863 execute_ipa_summary_passes
1864 ((struct ipa_opt_pass_d *) all_regular_ipa_passes);
1867 /* Some targets need to handle LTO assembler output specially. */
1868 if (flag_generate_lto)
1869 targetm.asm_out.lto_start ();
1871 execute_ipa_summary_passes ((struct ipa_opt_pass_d *) all_lto_gen_passes);
1874 ipa_write_summaries ();
1876 if (flag_generate_lto)
1877 targetm.asm_out.lto_end ();
1880 execute_ipa_pass_list (all_regular_ipa_passes);
1881 invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_END, NULL);
1883 bitmap_obstack_release (NULL);
1887 /* Perform simple optimizations based on callgraph. */
1890 cgraph_optimize (void)
1892 if (errorcount || sorrycount)
1895 #ifdef ENABLE_CHECKING
1899 /* Frontend may output common variables after the unit has been finalized.
1900 It is safe to deal with them here as they are always zero initialized. */
1901 varpool_analyze_pending_decls ();
1903 timevar_push (TV_CGRAPHOPT);
1904 if (pre_ipa_mem_report)
1906 fprintf (stderr, "Memory consumption before IPA\n");
1907 dump_memory_report (false);
1910 fprintf (stderr, "Performing interprocedural optimizations\n");
1911 cgraph_state = CGRAPH_STATE_IPA;
1913 /* Don't run the IPA passes if there was any error or sorry messages. */
1914 if (errorcount == 0 && sorrycount == 0)
1917 /* Do nothing else if any IPA pass found errors. */
1918 if (errorcount || sorrycount)
1920 timevar_pop (TV_CGRAPHOPT);
1924 /* This pass remove bodies of extern inline functions we never inlined.
1925 Do this later so other IPA passes see what is really going on. */
1926 cgraph_remove_unreachable_nodes (false, dump_file);
1927 cgraph_global_info_ready = true;
1928 if (cgraph_dump_file)
1930 fprintf (cgraph_dump_file, "Optimized ");
1931 dump_cgraph (cgraph_dump_file);
1932 dump_varpool (cgraph_dump_file);
1934 if (post_ipa_mem_report)
1936 fprintf (stderr, "Memory consumption after IPA\n");
1937 dump_memory_report (false);
1939 timevar_pop (TV_CGRAPHOPT);
1941 /* Output everything. */
1942 (*debug_hooks->assembly_start) ();
1944 fprintf (stderr, "Assembling functions:\n");
1945 #ifdef ENABLE_CHECKING
1949 cgraph_materialize_all_clones ();
1950 cgraph_mark_functions_to_output ();
1952 cgraph_state = CGRAPH_STATE_EXPANSION;
1953 if (!flag_toplevel_reorder)
1954 cgraph_output_in_order ();
1957 cgraph_output_pending_asms ();
1959 cgraph_expand_all_functions ();
1960 varpool_remove_unreferenced_decls ();
1962 varpool_assemble_pending_decls ();
1964 cgraph_process_new_functions ();
1965 cgraph_state = CGRAPH_STATE_FINISHED;
1967 if (cgraph_dump_file)
1969 fprintf (cgraph_dump_file, "\nFinal ");
1970 dump_cgraph (cgraph_dump_file);
1972 #ifdef ENABLE_CHECKING
1974 /* Double check that all inline clones are gone and that all
1975 function bodies have been released from memory. */
1976 if (!(sorrycount || errorcount))
1978 struct cgraph_node *node;
1979 bool error_found = false;
1981 for (node = cgraph_nodes; node; node = node->next)
1983 && (node->global.inlined_to
1984 || gimple_has_body_p (node->decl)))
1987 dump_cgraph_node (stderr, node);
1990 internal_error ("nodes with unreleased memory found");
1996 /* Generate and emit a static constructor or destructor. WHICH must
1997 be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
1998 is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
1999 initialization priority for this constructor or destructor. */
2002 cgraph_build_static_cdtor (char which, tree body, int priority)
2004 static int counter = 0;
2006 tree decl, name, resdecl;
2008 /* The priority is encoded in the constructor or destructor name.
2009 collect2 will sort the names and arrange that they are called at
2011 sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
2012 name = get_file_function_name (which_buf);
2014 decl = build_decl (input_location, FUNCTION_DECL, name,
2015 build_function_type (void_type_node, void_list_node));
2016 current_function_decl = decl;
2018 resdecl = build_decl (input_location,
2019 RESULT_DECL, NULL_TREE, void_type_node);
2020 DECL_ARTIFICIAL (resdecl) = 1;
2021 DECL_RESULT (decl) = resdecl;
2022 DECL_CONTEXT (resdecl) = decl;
2024 allocate_struct_function (decl, false);
2026 TREE_STATIC (decl) = 1;
2027 TREE_USED (decl) = 1;
2028 DECL_ARTIFICIAL (decl) = 1;
2029 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
2030 DECL_SAVED_TREE (decl) = body;
2031 if (!targetm.have_ctors_dtors)
2033 TREE_PUBLIC (decl) = 1;
2034 DECL_PRESERVE_P (decl) = 1;
2036 DECL_UNINLINABLE (decl) = 1;
2038 DECL_INITIAL (decl) = make_node (BLOCK);
2039 TREE_USED (DECL_INITIAL (decl)) = 1;
2041 DECL_SOURCE_LOCATION (decl) = input_location;
2042 cfun->function_end_locus = input_location;
2047 DECL_STATIC_CONSTRUCTOR (decl) = 1;
2048 decl_init_priority_insert (decl, priority);
2051 DECL_STATIC_DESTRUCTOR (decl) = 1;
2052 decl_fini_priority_insert (decl, priority);
2058 gimplify_function_tree (decl);
2060 cgraph_add_new_function (decl, false);
2061 cgraph_mark_needed_node (cgraph_node (decl));
2068 cgraph_dump_file = dump_begin (TDI_cgraph, NULL);
2071 /* The edges representing the callers of the NEW_VERSION node were
2072 fixed by cgraph_function_versioning (), now the call_expr in their
2073 respective tree code should be updated to call the NEW_VERSION. */
2076 update_call_expr (struct cgraph_node *new_version)
2078 struct cgraph_edge *e;
2080 gcc_assert (new_version);
2082 /* Update the call expr on the edges to call the new version. */
2083 for (e = new_version->callers; e; e = e->next_caller)
2085 struct function *inner_function = DECL_STRUCT_FUNCTION (e->caller->decl);
2086 gimple_call_set_fndecl (e->call_stmt, new_version->decl);
2087 maybe_clean_eh_stmt_fn (inner_function, e->call_stmt);
2092 /* Create a new cgraph node which is the new version of
2093 OLD_VERSION node. REDIRECT_CALLERS holds the callers
2094 edges which should be redirected to point to
2095 NEW_VERSION. ALL the callees edges of OLD_VERSION
2096 are cloned to the new version node. Return the new
2099 static struct cgraph_node *
2100 cgraph_copy_node_for_versioning (struct cgraph_node *old_version,
2102 VEC(cgraph_edge_p,heap) *redirect_callers)
2104 struct cgraph_node *new_version;
2105 struct cgraph_edge *e;
2106 struct cgraph_edge *next_callee;
2109 gcc_assert (old_version);
2111 new_version = cgraph_node (new_decl);
2113 new_version->analyzed = true;
2114 new_version->local = old_version->local;
2115 new_version->global = old_version->global;
2116 new_version->rtl = new_version->rtl;
2117 new_version->reachable = true;
2118 new_version->count = old_version->count;
2120 /* Clone the old node callees. Recursive calls are
2122 for (e = old_version->callees;e; e=e->next_callee)
2124 cgraph_clone_edge (e, new_version, e->call_stmt,
2125 e->lto_stmt_uid, REG_BR_PROB_BASE,
2127 e->loop_nest, true);
2129 /* Fix recursive calls.
2130 If OLD_VERSION has a recursive call after the
2131 previous edge cloning, the new version will have an edge
2132 pointing to the old version, which is wrong;
2133 Redirect it to point to the new version. */
2134 for (e = new_version->callees ; e; e = next_callee)
2136 next_callee = e->next_callee;
2137 if (e->callee == old_version)
2138 cgraph_redirect_edge_callee (e, new_version);
2143 for (i = 0; VEC_iterate (cgraph_edge_p, redirect_callers, i, e); i++)
2145 /* Redirect calls to the old version node to point to its new
2147 cgraph_redirect_edge_callee (e, new_version);
2153 /* Perform function versioning.
2154 Function versioning includes copying of the tree and
2155 a callgraph update (creating a new cgraph node and updating
2156 its callees and callers).
2158 REDIRECT_CALLERS varray includes the edges to be redirected
2161 TREE_MAP is a mapping of tree nodes we want to replace with
2162 new ones (according to results of prior analysis).
2163 OLD_VERSION_NODE is the node that is versioned.
2164 It returns the new version's cgraph node.
2165 ARGS_TO_SKIP lists arguments to be omitted from functions
2168 struct cgraph_node *
2169 cgraph_function_versioning (struct cgraph_node *old_version_node,
2170 VEC(cgraph_edge_p,heap) *redirect_callers,
2171 VEC (ipa_replace_map_p,gc)* tree_map,
2172 bitmap args_to_skip)
2174 tree old_decl = old_version_node->decl;
2175 struct cgraph_node *new_version_node = NULL;
2178 if (!tree_versionable_function_p (old_decl))
2181 /* Make a new FUNCTION_DECL tree node for the
2184 new_decl = copy_node (old_decl);
2186 new_decl = build_function_decl_skip_args (old_decl, args_to_skip);
2188 /* Create the new version's call-graph node.
2189 and update the edges of the new node. */
2191 cgraph_copy_node_for_versioning (old_version_node, new_decl,
2194 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2195 tree_function_versioning (old_decl, new_decl, tree_map, false, args_to_skip);
2197 /* Update the new version's properties.
2198 Make The new version visible only within this translation unit. Make sure
2199 that is not weak also.
2200 ??? We cannot use COMDAT linkage because there is no
2201 ABI support for this. */
2202 cgraph_make_decl_local (new_version_node->decl);
2203 DECL_VIRTUAL_P (new_version_node->decl) = 0;
2204 new_version_node->local.externally_visible = 0;
2205 new_version_node->local.local = 1;
2206 new_version_node->lowered = true;
2208 /* Update the call_expr on the edges to call the new version node. */
2209 update_call_expr (new_version_node);
2211 cgraph_call_function_insertion_hooks (new_version_node);
2212 return new_version_node;
2215 /* Produce separate function body for inline clones so the offline copy can be
2216 modified without affecting them. */
2217 struct cgraph_node *
2218 save_inline_function_body (struct cgraph_node *node)
2220 struct cgraph_node *first_clone, *n;
2222 gcc_assert (node == cgraph_node (node->decl));
2224 cgraph_lower_function (node);
2226 first_clone = node->clones;
2228 first_clone->decl = copy_node (node->decl);
2229 cgraph_insert_node_to_hashtable (first_clone);
2230 gcc_assert (first_clone == cgraph_node (first_clone->decl));
2231 if (first_clone->next_sibling_clone)
2233 for (n = first_clone->next_sibling_clone; n->next_sibling_clone; n = n->next_sibling_clone)
2234 n->clone_of = first_clone;
2235 n->clone_of = first_clone;
2236 n->next_sibling_clone = first_clone->clones;
2237 if (first_clone->clones)
2238 first_clone->clones->prev_sibling_clone = n;
2239 first_clone->clones = first_clone->next_sibling_clone;
2240 first_clone->next_sibling_clone->prev_sibling_clone = NULL;
2241 first_clone->next_sibling_clone = NULL;
2242 gcc_assert (!first_clone->prev_sibling_clone);
2244 first_clone->clone_of = NULL;
2245 node->clones = NULL;
2247 if (first_clone->clones)
2248 for (n = first_clone->clones; n != first_clone;)
2250 gcc_assert (n->decl == node->decl);
2251 n->decl = first_clone->decl;
2254 else if (n->next_sibling_clone)
2255 n = n->next_sibling_clone;
2258 while (n != first_clone && !n->next_sibling_clone)
2260 if (n != first_clone)
2261 n = n->next_sibling_clone;
2265 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2266 tree_function_versioning (node->decl, first_clone->decl, NULL, true, NULL);
2268 DECL_EXTERNAL (first_clone->decl) = 0;
2269 DECL_COMDAT_GROUP (first_clone->decl) = NULL_TREE;
2270 TREE_PUBLIC (first_clone->decl) = 0;
2271 DECL_COMDAT (first_clone->decl) = 0;
2272 VEC_free (ipa_opt_pass, heap,
2273 first_clone->ipa_transforms_to_apply);
2274 first_clone->ipa_transforms_to_apply = NULL;
2276 #ifdef ENABLE_CHECKING
2277 verify_cgraph_node (first_clone);
2282 /* Given virtual clone, turn it into actual clone. */
2284 cgraph_materialize_clone (struct cgraph_node *node)
2286 bitmap_obstack_initialize (NULL);
2287 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2288 tree_function_versioning (node->clone_of->decl, node->decl,
2289 node->clone.tree_map, true,
2290 node->clone.args_to_skip);
2291 if (cgraph_dump_file)
2293 dump_function_to_file (node->clone_of->decl, cgraph_dump_file, dump_flags);
2294 dump_function_to_file (node->decl, cgraph_dump_file, dump_flags);
2297 /* Function is no longer clone. */
2298 if (node->next_sibling_clone)
2299 node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
2300 if (node->prev_sibling_clone)
2301 node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
2303 node->clone_of->clones = node->next_sibling_clone;
2304 node->next_sibling_clone = NULL;
2305 node->prev_sibling_clone = NULL;
2306 if (!node->clone_of->analyzed && !node->clone_of->clones)
2307 cgraph_remove_node (node->clone_of);
2308 node->clone_of = NULL;
2309 bitmap_obstack_release (NULL);
2312 /* If necessary, change the function declaration in the call statement
2313 associated with E so that it corresponds to the edge callee. */
2316 cgraph_redirect_edge_call_stmt_to_callee (struct cgraph_edge *e)
2318 tree decl = gimple_call_fndecl (e->call_stmt);
2320 gimple_stmt_iterator gsi;
2322 if (!decl || decl == e->callee->decl
2323 /* Don't update call from same body alias to the real function. */
2324 || cgraph_get_node (decl) == cgraph_get_node (e->callee->decl))
2325 return e->call_stmt;
2327 if (cgraph_dump_file)
2329 fprintf (cgraph_dump_file, "updating call of %s/%i -> %s/%i: ",
2330 cgraph_node_name (e->caller), e->caller->uid,
2331 cgraph_node_name (e->callee), e->callee->uid);
2332 print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
2335 if (e->callee->clone.combined_args_to_skip)
2336 new_stmt = gimple_call_copy_skip_args (e->call_stmt,
2337 e->callee->clone.combined_args_to_skip);
2339 new_stmt = e->call_stmt;
2340 if (gimple_vdef (new_stmt)
2341 && TREE_CODE (gimple_vdef (new_stmt)) == SSA_NAME)
2342 SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;
2343 gimple_call_set_fndecl (new_stmt, e->callee->decl);
2345 gsi = gsi_for_stmt (e->call_stmt);
2346 gsi_replace (&gsi, new_stmt, true);
2348 /* Update EH information too, just in case. */
2349 maybe_clean_or_replace_eh_stmt (e->call_stmt, new_stmt);
2351 cgraph_set_call_stmt_including_clones (e->caller, e->call_stmt, new_stmt);
2353 if (cgraph_dump_file)
2355 fprintf (cgraph_dump_file, " updated to:");
2356 print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
2361 /* Once all functions from compilation unit are in memory, produce all clones
2362 and update all calls. We might also do this on demand if we don't want to
2363 bring all functions to memory prior compilation, but current WHOPR
2364 implementation does that and it is is bit easier to keep everything right in
2367 cgraph_materialize_all_clones (void)
2369 struct cgraph_node *node;
2370 bool stabilized = false;
2372 if (cgraph_dump_file)
2373 fprintf (cgraph_dump_file, "Materializing clones\n");
2374 #ifdef ENABLE_CHECKING
2378 /* We can also do topological order, but number of iterations should be
2379 bounded by number of IPA passes since single IPA pass is probably not
2380 going to create clones of clones it created itself. */
2384 for (node = cgraph_nodes; node; node = node->next)
2386 if (node->clone_of && node->decl != node->clone_of->decl
2387 && !gimple_has_body_p (node->decl))
2389 if (gimple_has_body_p (node->clone_of->decl))
2391 if (cgraph_dump_file)
2393 fprintf (cgraph_dump_file, "clonning %s to %s\n",
2394 cgraph_node_name (node->clone_of),
2395 cgraph_node_name (node));
2396 if (node->clone.tree_map)
2399 fprintf (cgraph_dump_file, " replace map: ");
2400 for (i = 0; i < VEC_length (ipa_replace_map_p,
2401 node->clone.tree_map);
2404 struct ipa_replace_map *replace_info;
2405 replace_info = VEC_index (ipa_replace_map_p,
2406 node->clone.tree_map,
2408 print_generic_expr (cgraph_dump_file, replace_info->old_tree, 0);
2409 fprintf (cgraph_dump_file, " -> ");
2410 print_generic_expr (cgraph_dump_file, replace_info->new_tree, 0);
2411 fprintf (cgraph_dump_file, "%s%s;",
2412 replace_info->replace_p ? "(replace)":"",
2413 replace_info->ref_p ? "(ref)":"");
2415 fprintf (cgraph_dump_file, "\n");
2417 if (node->clone.args_to_skip)
2419 fprintf (cgraph_dump_file, " args_to_skip: ");
2420 dump_bitmap (cgraph_dump_file, node->clone.args_to_skip);
2422 if (node->clone.args_to_skip)
2424 fprintf (cgraph_dump_file, " combined_args_to_skip:");
2425 dump_bitmap (cgraph_dump_file, node->clone.combined_args_to_skip);
2428 cgraph_materialize_clone (node);
2434 for (node = cgraph_nodes; node; node = node->next)
2435 if (!node->analyzed && node->callees)
2436 cgraph_node_remove_callees (node);
2437 if (cgraph_dump_file)
2438 fprintf (cgraph_dump_file, "Updating call sites\n");
2439 for (node = cgraph_nodes; node; node = node->next)
2440 if (node->analyzed && !node->clone_of
2441 && gimple_has_body_p (node->decl))
2443 struct cgraph_edge *e;
2445 current_function_decl = node->decl;
2446 push_cfun (DECL_STRUCT_FUNCTION (node->decl));
2447 for (e = node->callees; e; e = e->next_callee)
2448 cgraph_redirect_edge_call_stmt_to_callee (e);
2450 current_function_decl = NULL;
2451 #ifdef ENABLE_CHECKING
2452 verify_cgraph_node (node);
2455 if (cgraph_dump_file)
2456 fprintf (cgraph_dump_file, "Materialization Call site updates done.\n");
2457 /* All changes to parameters have been performed. In order not to
2458 incorrectly repeat them, we simply dispose of the bitmaps that drive the
2460 for (node = cgraph_nodes; node; node = node->next)
2461 node->clone.combined_args_to_skip = NULL;
2462 #ifdef ENABLE_CHECKING
2465 cgraph_remove_unreachable_nodes (false, cgraph_dump_file);
2468 #include "gt-cgraphunit.h"