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:");
817 error ("an indirect edge with unknown callee "
818 "corresponding to a call_stmt with "
819 "a known declaration:");
821 debug_gimple_stmt (e->call_stmt);
827 error ("missing callgraph edge for call stmt:");
828 debug_gimple_stmt (stmt);
833 pointer_set_destroy (visited_nodes);
836 /* No CFG available?! */
839 for (e = node->callees; e; e = e->next_callee)
843 error ("edge %s->%s has no corresponding call_stmt",
844 identifier_to_locale (cgraph_node_name (e->caller)),
845 identifier_to_locale (cgraph_node_name (e->callee)));
846 debug_gimple_stmt (e->call_stmt);
851 for (e = node->indirect_calls; e; e = e->next_callee)
855 error ("an indirect edge from %s has no corresponding call_stmt",
856 identifier_to_locale (cgraph_node_name (e->caller)));
857 debug_gimple_stmt (e->call_stmt);
865 dump_cgraph_node (stderr, node);
866 internal_error ("verify_cgraph_node failed");
868 set_cfun (saved_cfun);
869 timevar_pop (TV_CGRAPH_VERIFY);
872 /* Verify whole cgraph structure. */
876 struct cgraph_node *node;
878 if (sorrycount || errorcount)
881 for (node = cgraph_nodes; node; node = node->next)
882 verify_cgraph_node (node);
885 /* Output all asm statements we have stored up to be output. */
888 cgraph_output_pending_asms (void)
890 struct cgraph_asm_node *can;
892 if (errorcount || sorrycount)
895 for (can = cgraph_asm_nodes; can; can = can->next)
896 assemble_asm (can->asm_str);
897 cgraph_asm_nodes = NULL;
900 /* Analyze the function scheduled to be output. */
902 cgraph_analyze_function (struct cgraph_node *node)
904 tree save = current_function_decl;
905 tree decl = node->decl;
907 current_function_decl = decl;
908 push_cfun (DECL_STRUCT_FUNCTION (decl));
910 assign_assembler_name_if_neeeded (node->decl);
912 /* Make sure to gimplify bodies only once. During analyzing a
913 function we lower it, which will require gimplified nested
914 functions, so we can end up here with an already gimplified
916 if (!gimple_body (decl))
917 gimplify_function_tree (decl);
918 dump_function (TDI_generic, decl);
920 cgraph_lower_function (node);
921 node->analyzed = true;
924 current_function_decl = save;
927 /* Look for externally_visible and used attributes and mark cgraph nodes
930 We cannot mark the nodes at the point the attributes are processed (in
931 handle_*_attribute) because the copy of the declarations available at that
932 point may not be canonical. For example, in:
935 void f() __attribute__((used));
937 the declaration we see in handle_used_attribute will be the second
938 declaration -- but the front end will subsequently merge that declaration
939 with the original declaration and discard the second declaration.
941 Furthermore, we can't mark these nodes in cgraph_finalize_function because:
944 void f() __attribute__((externally_visible));
948 So, we walk the nodes at the end of the translation unit, applying the
949 attributes at that point. */
952 process_function_and_variable_attributes (struct cgraph_node *first,
953 struct varpool_node *first_var)
955 struct cgraph_node *node;
956 struct varpool_node *vnode;
958 for (node = cgraph_nodes; node != first; node = node->next)
960 tree decl = node->decl;
961 if (DECL_PRESERVE_P (decl))
963 mark_decl_referenced (decl);
964 if (node->local.finalized)
965 cgraph_mark_needed_node (node);
967 if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
969 if (! TREE_PUBLIC (node->decl))
970 warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes,
971 "%<externally_visible%>"
972 " attribute have effect only on public objects");
973 else if (node->local.finalized)
974 cgraph_mark_needed_node (node);
977 for (vnode = varpool_nodes; vnode != first_var; vnode = vnode->next)
979 tree decl = vnode->decl;
980 if (DECL_PRESERVE_P (decl))
982 mark_decl_referenced (decl);
983 vnode->force_output = true;
984 if (vnode->finalized)
985 varpool_mark_needed_node (vnode);
987 if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
989 if (! TREE_PUBLIC (vnode->decl))
990 warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes,
991 "%<externally_visible%>"
992 " attribute have effect only on public objects");
993 else if (vnode->finalized)
994 varpool_mark_needed_node (vnode);
999 /* Process CGRAPH_NODES_NEEDED queue, analyze each function (and transitively
1000 each reachable functions) and build cgraph.
1001 The function can be called multiple times after inserting new nodes
1002 into beginning of queue. Just the new part of queue is re-scanned then. */
1005 cgraph_analyze_functions (void)
1007 /* Keep track of already processed nodes when called multiple times for
1008 intermodule optimization. */
1009 static struct cgraph_node *first_analyzed;
1010 struct cgraph_node *first_processed = first_analyzed;
1011 static struct varpool_node *first_analyzed_var;
1012 struct cgraph_node *node, *next;
1014 process_function_and_variable_attributes (first_processed,
1015 first_analyzed_var);
1016 first_processed = cgraph_nodes;
1017 first_analyzed_var = varpool_nodes;
1018 varpool_analyze_pending_decls ();
1019 if (cgraph_dump_file)
1021 fprintf (cgraph_dump_file, "Initial entry points:");
1022 for (node = cgraph_nodes; node != first_analyzed; node = node->next)
1024 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1025 fprintf (cgraph_dump_file, "\n");
1027 cgraph_process_new_functions ();
1029 /* Propagate reachability flag and lower representation of all reachable
1030 functions. In the future, lowering will introduce new functions and
1031 new entry points on the way (by template instantiation and virtual
1032 method table generation for instance). */
1033 while (cgraph_nodes_queue)
1035 struct cgraph_edge *edge;
1036 tree decl = cgraph_nodes_queue->decl;
1038 node = cgraph_nodes_queue;
1039 cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
1040 node->next_needed = NULL;
1042 /* ??? It is possible to create extern inline function and later using
1043 weak alias attribute to kill its body. See
1044 gcc.c-torture/compile/20011119-1.c */
1045 if (!DECL_STRUCT_FUNCTION (decl))
1047 cgraph_reset_node (node);
1051 if (!node->analyzed)
1052 cgraph_analyze_function (node);
1054 for (edge = node->callees; edge; edge = edge->next_callee)
1055 if (!edge->callee->reachable)
1056 cgraph_mark_reachable_node (edge->callee);
1058 if (node->same_comdat_group)
1060 for (next = node->same_comdat_group;
1062 next = next->same_comdat_group)
1063 cgraph_mark_reachable_node (next);
1066 /* If decl is a clone of an abstract function, mark that abstract
1067 function so that we don't release its body. The DECL_INITIAL() of that
1068 abstract function declaration will be later needed to output debug info. */
1069 if (DECL_ABSTRACT_ORIGIN (decl))
1071 struct cgraph_node *origin_node = cgraph_node (DECL_ABSTRACT_ORIGIN (decl));
1072 origin_node->abstract_and_needed = true;
1075 /* We finalize local static variables during constructing callgraph
1076 edges. Process their attributes too. */
1077 process_function_and_variable_attributes (first_processed,
1078 first_analyzed_var);
1079 first_processed = cgraph_nodes;
1080 first_analyzed_var = varpool_nodes;
1081 varpool_analyze_pending_decls ();
1082 cgraph_process_new_functions ();
1085 /* Collect entry points to the unit. */
1086 if (cgraph_dump_file)
1088 fprintf (cgraph_dump_file, "Unit entry points:");
1089 for (node = cgraph_nodes; node != first_analyzed; node = node->next)
1091 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1092 fprintf (cgraph_dump_file, "\n\nInitial ");
1093 dump_cgraph (cgraph_dump_file);
1096 if (cgraph_dump_file)
1097 fprintf (cgraph_dump_file, "\nReclaiming functions:");
1099 for (node = cgraph_nodes; node != first_analyzed; node = next)
1101 tree decl = node->decl;
1104 if (node->local.finalized && !gimple_has_body_p (decl))
1105 cgraph_reset_node (node);
1107 if (!node->reachable && gimple_has_body_p (decl))
1109 if (cgraph_dump_file)
1110 fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
1111 cgraph_remove_node (node);
1115 node->next_needed = NULL;
1116 gcc_assert (!node->local.finalized || gimple_has_body_p (decl));
1117 gcc_assert (node->analyzed == node->local.finalized);
1119 if (cgraph_dump_file)
1121 fprintf (cgraph_dump_file, "\n\nReclaimed ");
1122 dump_cgraph (cgraph_dump_file);
1124 first_analyzed = cgraph_nodes;
1129 /* Analyze the whole compilation unit once it is parsed completely. */
1132 cgraph_finalize_compilation_unit (void)
1134 timevar_push (TV_CGRAPH);
1136 /* Do not skip analyzing the functions if there were errors, we
1137 miss diagnostics for following functions otherwise. */
1139 /* Emit size functions we didn't inline. */
1140 finalize_size_functions ();
1142 /* Call functions declared with the "constructor" or "destructor"
1144 cgraph_build_cdtor_fns ();
1146 /* Mark alias targets necessary and emit diagnostics. */
1147 finish_aliases_1 ();
1151 fprintf (stderr, "\nAnalyzing compilation unit\n");
1155 /* Gimplify and lower all functions, compute reachability and
1156 remove unreachable nodes. */
1157 cgraph_analyze_functions ();
1159 /* Mark alias targets necessary and emit diagnostics. */
1160 finish_aliases_1 ();
1162 /* Gimplify and lower thunks. */
1163 cgraph_analyze_functions ();
1165 /* Finally drive the pass manager. */
1168 timevar_pop (TV_CGRAPH);
1172 /* Figure out what functions we want to assemble. */
1175 cgraph_mark_functions_to_output (void)
1177 struct cgraph_node *node;
1178 #ifdef ENABLE_CHECKING
1179 bool check_same_comdat_groups = false;
1181 for (node = cgraph_nodes; node; node = node->next)
1182 gcc_assert (!node->process);
1185 for (node = cgraph_nodes; node; node = node->next)
1187 tree decl = node->decl;
1188 struct cgraph_edge *e;
1190 gcc_assert (!node->process || node->same_comdat_group);
1194 for (e = node->callers; e; e = e->next_caller)
1195 if (e->inline_failed)
1198 /* We need to output all local functions that are used and not
1199 always inlined, as well as those that are reachable from
1200 outside the current compilation unit. */
1202 && !node->global.inlined_to
1203 && (node->needed || node->reachable_from_other_partition
1204 || node->address_taken
1205 || (e && node->reachable))
1206 && !TREE_ASM_WRITTEN (decl)
1207 && !DECL_EXTERNAL (decl))
1210 if (node->same_comdat_group)
1212 struct cgraph_node *next;
1213 for (next = node->same_comdat_group;
1215 next = next->same_comdat_group)
1219 else if (node->same_comdat_group)
1221 #ifdef ENABLE_CHECKING
1222 check_same_comdat_groups = true;
1227 /* We should've reclaimed all functions that are not needed. */
1228 #ifdef ENABLE_CHECKING
1229 if (!node->global.inlined_to
1230 && gimple_has_body_p (decl)
1231 /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
1232 are inside partition, we can end up not removing the body since we no longer
1233 have analyzed node pointing to it. */
1234 && !node->in_other_partition
1235 && !DECL_EXTERNAL (decl))
1237 dump_cgraph_node (stderr, node);
1238 internal_error ("failed to reclaim unneeded function");
1241 gcc_assert (node->global.inlined_to
1242 || !gimple_has_body_p (decl)
1243 || node->in_other_partition
1244 || DECL_EXTERNAL (decl));
1249 #ifdef ENABLE_CHECKING
1250 if (check_same_comdat_groups)
1251 for (node = cgraph_nodes; node; node = node->next)
1252 if (node->same_comdat_group && !node->process)
1254 tree decl = node->decl;
1255 if (!node->global.inlined_to
1256 && gimple_has_body_p (decl)
1257 /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
1258 are inside partition, we can end up not removing the body since we no longer
1259 have analyzed node pointing to it. */
1260 && !node->in_other_partition
1261 && !DECL_EXTERNAL (decl))
1263 dump_cgraph_node (stderr, node);
1264 internal_error ("failed to reclaim unneeded function");
1270 /* DECL is FUNCTION_DECL. Initialize datastructures so DECL is a function
1271 in lowered gimple form.
1273 Set current_function_decl and cfun to newly constructed empty function body.
1274 return basic block in the function body. */
1277 init_lowered_empty_function (tree decl)
1281 current_function_decl = decl;
1282 allocate_struct_function (decl, false);
1283 gimple_register_cfg_hooks ();
1284 init_empty_tree_cfg ();
1285 init_tree_ssa (cfun);
1286 init_ssa_operands ();
1287 cfun->gimple_df->in_ssa_p = true;
1288 DECL_INITIAL (decl) = make_node (BLOCK);
1290 DECL_SAVED_TREE (decl) = error_mark_node;
1291 cfun->curr_properties |=
1292 (PROP_gimple_lcf | PROP_gimple_leh | PROP_cfg | PROP_referenced_vars |
1295 /* Create BB for body of the function and connect it properly. */
1296 bb = create_basic_block (NULL, (void *) 0, ENTRY_BLOCK_PTR);
1297 make_edge (ENTRY_BLOCK_PTR, bb, 0);
1298 make_edge (bb, EXIT_BLOCK_PTR, 0);
1303 /* Adjust PTR by the constant FIXED_OFFSET, and by the vtable
1304 offset indicated by VIRTUAL_OFFSET, if that is
1305 non-null. THIS_ADJUSTING is nonzero for a this adjusting thunk and
1306 zero for a result adjusting thunk. */
1309 thunk_adjust (gimple_stmt_iterator * bsi,
1310 tree ptr, bool this_adjusting,
1311 HOST_WIDE_INT fixed_offset, tree virtual_offset)
1317 && fixed_offset != 0)
1319 stmt = gimple_build_assign (ptr,
1320 fold_build2_loc (input_location,
1322 TREE_TYPE (ptr), ptr,
1323 size_int (fixed_offset)));
1324 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1327 /* If there's a virtual offset, look up that value in the vtable and
1328 adjust the pointer again. */
1336 if (!vtable_entry_type)
1338 tree vfunc_type = make_node (FUNCTION_TYPE);
1339 TREE_TYPE (vfunc_type) = integer_type_node;
1340 TYPE_ARG_TYPES (vfunc_type) = NULL_TREE;
1341 layout_type (vfunc_type);
1343 vtable_entry_type = build_pointer_type (vfunc_type);
1347 create_tmp_var (build_pointer_type
1348 (build_pointer_type (vtable_entry_type)), "vptr");
1350 /* The vptr is always at offset zero in the object. */
1351 stmt = gimple_build_assign (vtabletmp,
1352 build1 (NOP_EXPR, TREE_TYPE (vtabletmp),
1354 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1355 mark_symbols_for_renaming (stmt);
1356 find_referenced_vars_in (stmt);
1358 /* Form the vtable address. */
1359 vtabletmp2 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp)),
1361 stmt = gimple_build_assign (vtabletmp2,
1362 build1 (INDIRECT_REF,
1363 TREE_TYPE (vtabletmp2), vtabletmp));
1364 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1365 mark_symbols_for_renaming (stmt);
1366 find_referenced_vars_in (stmt);
1368 /* Find the entry with the vcall offset. */
1369 stmt = gimple_build_assign (vtabletmp2,
1370 fold_build2_loc (input_location,
1372 TREE_TYPE (vtabletmp2),
1374 fold_convert (sizetype,
1376 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1378 /* Get the offset itself. */
1379 vtabletmp3 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp2)),
1381 stmt = gimple_build_assign (vtabletmp3,
1382 build1 (INDIRECT_REF,
1383 TREE_TYPE (vtabletmp3),
1385 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1386 mark_symbols_for_renaming (stmt);
1387 find_referenced_vars_in (stmt);
1389 /* Cast to sizetype. */
1390 offsettmp = create_tmp_var (sizetype, "offset");
1391 stmt = gimple_build_assign (offsettmp, fold_convert (sizetype, vtabletmp3));
1392 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1393 mark_symbols_for_renaming (stmt);
1394 find_referenced_vars_in (stmt);
1396 /* Adjust the `this' pointer. */
1397 ptr = fold_build2_loc (input_location,
1398 POINTER_PLUS_EXPR, TREE_TYPE (ptr), ptr,
1403 && fixed_offset != 0)
1404 /* Adjust the pointer by the constant. */
1408 if (TREE_CODE (ptr) == VAR_DECL)
1412 ptrtmp = create_tmp_var (TREE_TYPE (ptr), "ptr");
1413 stmt = gimple_build_assign (ptrtmp, ptr);
1414 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1415 mark_symbols_for_renaming (stmt);
1416 find_referenced_vars_in (stmt);
1418 ptr = fold_build2_loc (input_location,
1419 POINTER_PLUS_EXPR, TREE_TYPE (ptrtmp), ptrtmp,
1420 size_int (fixed_offset));
1423 /* Emit the statement and gimplify the adjustment expression. */
1424 ret = create_tmp_var (TREE_TYPE (ptr), "adjusted_this");
1425 stmt = gimple_build_assign (ret, ptr);
1426 mark_symbols_for_renaming (stmt);
1427 find_referenced_vars_in (stmt);
1428 gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
1433 /* Produce assembler for thunk NODE. */
1436 assemble_thunk (struct cgraph_node *node)
1438 bool this_adjusting = node->thunk.this_adjusting;
1439 HOST_WIDE_INT fixed_offset = node->thunk.fixed_offset;
1440 HOST_WIDE_INT virtual_value = node->thunk.virtual_value;
1441 tree virtual_offset = NULL;
1442 tree alias = node->thunk.alias;
1443 tree thunk_fndecl = node->decl;
1444 tree a = DECL_ARGUMENTS (thunk_fndecl);
1446 current_function_decl = thunk_fndecl;
1449 && targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset,
1450 virtual_value, alias))
1455 DECL_RESULT (thunk_fndecl)
1456 = build_decl (DECL_SOURCE_LOCATION (thunk_fndecl),
1457 RESULT_DECL, 0, integer_type_node);
1458 fnname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk_fndecl));
1460 /* The back end expects DECL_INITIAL to contain a BLOCK, so we
1462 fn_block = make_node (BLOCK);
1463 BLOCK_VARS (fn_block) = a;
1464 DECL_INITIAL (thunk_fndecl) = fn_block;
1465 init_function_start (thunk_fndecl);
1467 assemble_start_function (thunk_fndecl, fnname);
1469 targetm.asm_out.output_mi_thunk (asm_out_file, thunk_fndecl,
1470 fixed_offset, virtual_value, alias);
1472 assemble_end_function (thunk_fndecl, fnname);
1473 init_insn_lengths ();
1474 free_after_compilation (cfun);
1476 TREE_ASM_WRITTEN (thunk_fndecl) = 1;
1481 basic_block bb, then_bb, else_bb, return_bb;
1482 gimple_stmt_iterator bsi;
1488 VEC(tree, heap) *vargs;
1493 DECL_IGNORED_P (thunk_fndecl) = 1;
1494 bitmap_obstack_initialize (NULL);
1496 if (node->thunk.virtual_offset_p)
1497 virtual_offset = size_int (virtual_value);
1499 /* Build the return declaration for the function. */
1500 restype = TREE_TYPE (TREE_TYPE (thunk_fndecl));
1501 if (DECL_RESULT (thunk_fndecl) == NULL_TREE)
1503 resdecl = build_decl (input_location, RESULT_DECL, 0, restype);
1504 DECL_ARTIFICIAL (resdecl) = 1;
1505 DECL_IGNORED_P (resdecl) = 1;
1506 DECL_RESULT (thunk_fndecl) = resdecl;
1509 resdecl = DECL_RESULT (thunk_fndecl);
1511 bb = then_bb = else_bb = return_bb = init_lowered_empty_function (thunk_fndecl);
1513 bsi = gsi_start_bb (bb);
1515 /* Build call to the function being thunked. */
1516 if (!VOID_TYPE_P (restype))
1518 if (!is_gimple_reg_type (restype))
1521 cfun->local_decls = tree_cons (NULL_TREE, restmp, cfun->local_decls);
1522 BLOCK_VARS (DECL_INITIAL (current_function_decl)) = restmp;
1525 restmp = create_tmp_var_raw (restype, "retval");
1528 for (arg = a; arg; arg = TREE_CHAIN (arg))
1530 vargs = VEC_alloc (tree, heap, nargs);
1532 VEC_quick_push (tree, vargs,
1537 VEC_quick_push (tree, vargs, a);
1538 for (i = 1, arg = TREE_CHAIN (a); i < nargs; i++, arg = TREE_CHAIN (arg))
1539 VEC_quick_push (tree, vargs, arg);
1540 call = gimple_build_call_vec (build_fold_addr_expr_loc (0, alias), vargs);
1541 VEC_free (tree, heap, vargs);
1542 gimple_call_set_cannot_inline (call, true);
1543 gimple_call_set_from_thunk (call, true);
1545 gimple_call_set_lhs (call, restmp);
1546 gsi_insert_after (&bsi, call, GSI_NEW_STMT);
1547 mark_symbols_for_renaming (call);
1548 find_referenced_vars_in (call);
1551 if (restmp && !this_adjusting)
1553 tree true_label = NULL_TREE;
1555 if (TREE_CODE (TREE_TYPE (restmp)) == POINTER_TYPE)
1558 /* If the return type is a pointer, we need to
1559 protect against NULL. We know there will be an
1560 adjustment, because that's why we're emitting a
1562 then_bb = create_basic_block (NULL, (void *) 0, bb);
1563 return_bb = create_basic_block (NULL, (void *) 0, then_bb);
1564 else_bb = create_basic_block (NULL, (void *) 0, else_bb);
1565 remove_edge (single_succ_edge (bb));
1566 true_label = gimple_block_label (then_bb);
1567 stmt = gimple_build_cond (NE_EXPR, restmp,
1568 fold_convert (TREE_TYPE (restmp),
1570 NULL_TREE, NULL_TREE);
1571 gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
1572 make_edge (bb, then_bb, EDGE_TRUE_VALUE);
1573 make_edge (bb, else_bb, EDGE_FALSE_VALUE);
1574 make_edge (return_bb, EXIT_BLOCK_PTR, 0);
1575 make_edge (then_bb, return_bb, EDGE_FALLTHRU);
1576 make_edge (else_bb, return_bb, EDGE_FALLTHRU);
1577 bsi = gsi_last_bb (then_bb);
1580 restmp = thunk_adjust (&bsi, restmp, /*this_adjusting=*/0,
1581 fixed_offset, virtual_offset);
1585 bsi = gsi_last_bb (else_bb);
1586 stmt = gimple_build_assign (restmp, fold_convert (TREE_TYPE (restmp),
1587 integer_zero_node));
1588 gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
1589 bsi = gsi_last_bb (return_bb);
1593 gimple_call_set_tail (call, true);
1595 /* Build return value. */
1596 ret = gimple_build_return (restmp);
1597 gsi_insert_after (&bsi, ret, GSI_NEW_STMT);
1599 delete_unreachable_blocks ();
1600 update_ssa (TODO_update_ssa);
1602 cgraph_remove_same_body_alias (node);
1603 /* Since we want to emit the thunk, we explicitly mark its name as
1605 mark_decl_referenced (thunk_fndecl);
1606 cgraph_add_new_function (thunk_fndecl, true);
1607 bitmap_obstack_release (NULL);
1609 current_function_decl = NULL;
1612 /* Expand function specified by NODE. */
1615 cgraph_expand_function (struct cgraph_node *node)
1617 tree decl = node->decl;
1619 /* We ought to not compile any inline clones. */
1620 gcc_assert (!node->global.inlined_to);
1622 announce_function (decl);
1625 gcc_assert (node->lowered);
1627 /* Generate RTL for the body of DECL. */
1628 tree_rest_of_compilation (decl);
1630 /* Make sure that BE didn't give up on compiling. */
1631 gcc_assert (TREE_ASM_WRITTEN (decl));
1632 current_function_decl = NULL;
1633 if (node->same_body)
1635 struct cgraph_node *alias, *next;
1636 bool saved_alias = node->alias;
1637 for (alias = node->same_body;
1638 alias && alias->next; alias = alias->next)
1640 /* Walk aliases in the order they were created; it is possible that
1641 thunks reffers to the aliases made earlier. */
1642 for (; alias; alias = next)
1644 next = alias->previous;
1645 if (!alias->thunk.thunk_p)
1646 assemble_alias (alias->decl,
1647 DECL_ASSEMBLER_NAME (alias->thunk.alias));
1649 assemble_thunk (alias);
1651 node->alias = saved_alias;
1653 gcc_assert (!cgraph_preserve_function_body_p (decl));
1654 cgraph_release_function_body (node);
1655 /* Eliminate all call edges. This is important so the GIMPLE_CALL no longer
1656 points to the dead function body. */
1657 cgraph_node_remove_callees (node);
1659 cgraph_function_flags_ready = true;
1662 /* Return true when CALLER_DECL should be inlined into CALLEE_DECL. */
1665 cgraph_inline_p (struct cgraph_edge *e, cgraph_inline_failed_t *reason)
1667 *reason = e->inline_failed;
1668 return !e->inline_failed;
1673 /* Expand all functions that must be output.
1675 Attempt to topologically sort the nodes so function is output when
1676 all called functions are already assembled to allow data to be
1677 propagated across the callgraph. Use a stack to get smaller distance
1678 between a function and its callees (later we may choose to use a more
1679 sophisticated algorithm for function reordering; we will likely want
1680 to use subsections to make the output functions appear in top-down
1684 cgraph_expand_all_functions (void)
1686 struct cgraph_node *node;
1687 struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
1688 int order_pos, new_order_pos = 0;
1691 order_pos = cgraph_postorder (order);
1692 gcc_assert (order_pos == cgraph_n_nodes);
1694 /* Garbage collector may remove inline clones we eliminate during
1695 optimization. So we must be sure to not reference them. */
1696 for (i = 0; i < order_pos; i++)
1697 if (order[i]->process)
1698 order[new_order_pos++] = order[i];
1700 for (i = new_order_pos - 1; i >= 0; i--)
1705 gcc_assert (node->reachable);
1707 cgraph_expand_function (node);
1710 cgraph_process_new_functions ();
1716 /* This is used to sort the node types by the cgraph order number. */
1718 enum cgraph_order_sort_kind
1720 ORDER_UNDEFINED = 0,
1726 struct cgraph_order_sort
1728 enum cgraph_order_sort_kind kind;
1731 struct cgraph_node *f;
1732 struct varpool_node *v;
1733 struct cgraph_asm_node *a;
1737 /* Output all functions, variables, and asm statements in the order
1738 according to their order fields, which is the order in which they
1739 appeared in the file. This implements -fno-toplevel-reorder. In
1740 this mode we may output functions and variables which don't really
1741 need to be output. */
1744 cgraph_output_in_order (void)
1747 struct cgraph_order_sort *nodes;
1749 struct cgraph_node *pf;
1750 struct varpool_node *pv;
1751 struct cgraph_asm_node *pa;
1754 nodes = XCNEWVEC (struct cgraph_order_sort, max);
1756 varpool_analyze_pending_decls ();
1758 for (pf = cgraph_nodes; pf; pf = pf->next)
1763 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1764 nodes[i].kind = ORDER_FUNCTION;
1769 for (pv = varpool_nodes_queue; pv; pv = pv->next_needed)
1772 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1773 nodes[i].kind = ORDER_VAR;
1777 for (pa = cgraph_asm_nodes; pa; pa = pa->next)
1780 gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
1781 nodes[i].kind = ORDER_ASM;
1785 /* In toplevel reorder mode we output all statics; mark them as needed. */
1786 for (i = 0; i < max; ++i)
1788 if (nodes[i].kind == ORDER_VAR)
1790 varpool_mark_needed_node (nodes[i].u.v);
1793 varpool_empty_needed_queue ();
1795 for (i = 0; i < max; ++i)
1797 switch (nodes[i].kind)
1799 case ORDER_FUNCTION:
1800 nodes[i].u.f->process = 0;
1801 cgraph_expand_function (nodes[i].u.f);
1805 varpool_assemble_decl (nodes[i].u.v);
1809 assemble_asm (nodes[i].u.a->asm_str);
1812 case ORDER_UNDEFINED:
1820 cgraph_asm_nodes = NULL;
1824 /* Return true when function body of DECL still needs to be kept around
1825 for later re-use. */
1827 cgraph_preserve_function_body_p (tree decl)
1829 struct cgraph_node *node;
1831 gcc_assert (cgraph_global_info_ready);
1832 /* Look if there is any clone around. */
1833 node = cgraph_node (decl);
1843 current_function_decl = NULL;
1844 gimple_register_cfg_hooks ();
1845 bitmap_obstack_initialize (NULL);
1847 invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_START, NULL);
1850 execute_ipa_pass_list (all_small_ipa_passes);
1852 /* If pass_all_early_optimizations was not scheduled, the state of
1853 the cgraph will not be properly updated. Update it now. */
1854 if (cgraph_state < CGRAPH_STATE_IPA_SSA)
1855 cgraph_state = CGRAPH_STATE_IPA_SSA;
1859 /* Generate coverage variables and constructors. */
1862 /* Process new functions added. */
1864 current_function_decl = NULL;
1865 cgraph_process_new_functions ();
1867 execute_ipa_summary_passes
1868 ((struct ipa_opt_pass_d *) all_regular_ipa_passes);
1871 /* Some targets need to handle LTO assembler output specially. */
1872 if (flag_generate_lto)
1873 targetm.asm_out.lto_start ();
1875 execute_ipa_summary_passes ((struct ipa_opt_pass_d *) all_lto_gen_passes);
1878 ipa_write_summaries ();
1880 if (flag_generate_lto)
1881 targetm.asm_out.lto_end ();
1884 execute_ipa_pass_list (all_regular_ipa_passes);
1885 invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_END, NULL);
1887 bitmap_obstack_release (NULL);
1891 /* Perform simple optimizations based on callgraph. */
1894 cgraph_optimize (void)
1896 if (errorcount || sorrycount)
1899 #ifdef ENABLE_CHECKING
1903 /* Frontend may output common variables after the unit has been finalized.
1904 It is safe to deal with them here as they are always zero initialized. */
1905 varpool_analyze_pending_decls ();
1907 timevar_push (TV_CGRAPHOPT);
1908 if (pre_ipa_mem_report)
1910 fprintf (stderr, "Memory consumption before IPA\n");
1911 dump_memory_report (false);
1914 fprintf (stderr, "Performing interprocedural optimizations\n");
1915 cgraph_state = CGRAPH_STATE_IPA;
1917 /* Don't run the IPA passes if there was any error or sorry messages. */
1918 if (errorcount == 0 && sorrycount == 0)
1921 /* Do nothing else if any IPA pass found errors. */
1922 if (errorcount || sorrycount)
1924 timevar_pop (TV_CGRAPHOPT);
1928 /* This pass remove bodies of extern inline functions we never inlined.
1929 Do this later so other IPA passes see what is really going on. */
1930 cgraph_remove_unreachable_nodes (false, dump_file);
1931 cgraph_global_info_ready = true;
1932 if (cgraph_dump_file)
1934 fprintf (cgraph_dump_file, "Optimized ");
1935 dump_cgraph (cgraph_dump_file);
1936 dump_varpool (cgraph_dump_file);
1938 if (post_ipa_mem_report)
1940 fprintf (stderr, "Memory consumption after IPA\n");
1941 dump_memory_report (false);
1943 timevar_pop (TV_CGRAPHOPT);
1945 /* Output everything. */
1946 (*debug_hooks->assembly_start) ();
1948 fprintf (stderr, "Assembling functions:\n");
1949 #ifdef ENABLE_CHECKING
1953 cgraph_materialize_all_clones ();
1954 cgraph_mark_functions_to_output ();
1956 cgraph_state = CGRAPH_STATE_EXPANSION;
1957 if (!flag_toplevel_reorder)
1958 cgraph_output_in_order ();
1961 cgraph_output_pending_asms ();
1963 cgraph_expand_all_functions ();
1964 varpool_remove_unreferenced_decls ();
1966 varpool_assemble_pending_decls ();
1968 cgraph_process_new_functions ();
1969 cgraph_state = CGRAPH_STATE_FINISHED;
1971 if (cgraph_dump_file)
1973 fprintf (cgraph_dump_file, "\nFinal ");
1974 dump_cgraph (cgraph_dump_file);
1976 #ifdef ENABLE_CHECKING
1978 /* Double check that all inline clones are gone and that all
1979 function bodies have been released from memory. */
1980 if (!(sorrycount || errorcount))
1982 struct cgraph_node *node;
1983 bool error_found = false;
1985 for (node = cgraph_nodes; node; node = node->next)
1987 && (node->global.inlined_to
1988 || gimple_has_body_p (node->decl)))
1991 dump_cgraph_node (stderr, node);
1994 internal_error ("nodes with unreleased memory found");
2000 /* Generate and emit a static constructor or destructor. WHICH must
2001 be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
2002 is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
2003 initialization priority for this constructor or destructor. */
2006 cgraph_build_static_cdtor (char which, tree body, int priority)
2008 static int counter = 0;
2010 tree decl, name, resdecl;
2012 /* The priority is encoded in the constructor or destructor name.
2013 collect2 will sort the names and arrange that they are called at
2015 sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
2016 name = get_file_function_name (which_buf);
2018 decl = build_decl (input_location, FUNCTION_DECL, name,
2019 build_function_type (void_type_node, void_list_node));
2020 current_function_decl = decl;
2022 resdecl = build_decl (input_location,
2023 RESULT_DECL, NULL_TREE, void_type_node);
2024 DECL_ARTIFICIAL (resdecl) = 1;
2025 DECL_RESULT (decl) = resdecl;
2026 DECL_CONTEXT (resdecl) = decl;
2028 allocate_struct_function (decl, false);
2030 TREE_STATIC (decl) = 1;
2031 TREE_USED (decl) = 1;
2032 DECL_ARTIFICIAL (decl) = 1;
2033 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
2034 DECL_SAVED_TREE (decl) = body;
2035 if (!targetm.have_ctors_dtors)
2037 TREE_PUBLIC (decl) = 1;
2038 DECL_PRESERVE_P (decl) = 1;
2040 DECL_UNINLINABLE (decl) = 1;
2042 DECL_INITIAL (decl) = make_node (BLOCK);
2043 TREE_USED (DECL_INITIAL (decl)) = 1;
2045 DECL_SOURCE_LOCATION (decl) = input_location;
2046 cfun->function_end_locus = input_location;
2051 DECL_STATIC_CONSTRUCTOR (decl) = 1;
2052 decl_init_priority_insert (decl, priority);
2055 DECL_STATIC_DESTRUCTOR (decl) = 1;
2056 decl_fini_priority_insert (decl, priority);
2062 gimplify_function_tree (decl);
2064 cgraph_add_new_function (decl, false);
2065 cgraph_mark_needed_node (cgraph_node (decl));
2072 cgraph_dump_file = dump_begin (TDI_cgraph, NULL);
2075 /* The edges representing the callers of the NEW_VERSION node were
2076 fixed by cgraph_function_versioning (), now the call_expr in their
2077 respective tree code should be updated to call the NEW_VERSION. */
2080 update_call_expr (struct cgraph_node *new_version)
2082 struct cgraph_edge *e;
2084 gcc_assert (new_version);
2086 /* Update the call expr on the edges to call the new version. */
2087 for (e = new_version->callers; e; e = e->next_caller)
2089 struct function *inner_function = DECL_STRUCT_FUNCTION (e->caller->decl);
2090 gimple_call_set_fndecl (e->call_stmt, new_version->decl);
2091 maybe_clean_eh_stmt_fn (inner_function, e->call_stmt);
2096 /* Create a new cgraph node which is the new version of
2097 OLD_VERSION node. REDIRECT_CALLERS holds the callers
2098 edges which should be redirected to point to
2099 NEW_VERSION. ALL the callees edges of OLD_VERSION
2100 are cloned to the new version node. Return the new
2103 static struct cgraph_node *
2104 cgraph_copy_node_for_versioning (struct cgraph_node *old_version,
2106 VEC(cgraph_edge_p,heap) *redirect_callers)
2108 struct cgraph_node *new_version;
2109 struct cgraph_edge *e;
2110 struct cgraph_edge *next_callee;
2113 gcc_assert (old_version);
2115 new_version = cgraph_node (new_decl);
2117 new_version->analyzed = true;
2118 new_version->local = old_version->local;
2119 new_version->global = old_version->global;
2120 new_version->rtl = new_version->rtl;
2121 new_version->reachable = true;
2122 new_version->count = old_version->count;
2124 /* Clone the old node callees. Recursive calls are
2126 for (e = old_version->callees;e; e=e->next_callee)
2128 cgraph_clone_edge (e, new_version, e->call_stmt,
2129 e->lto_stmt_uid, REG_BR_PROB_BASE,
2131 e->loop_nest, true);
2133 /* Fix recursive calls.
2134 If OLD_VERSION has a recursive call after the
2135 previous edge cloning, the new version will have an edge
2136 pointing to the old version, which is wrong;
2137 Redirect it to point to the new version. */
2138 for (e = new_version->callees ; e; e = next_callee)
2140 next_callee = e->next_callee;
2141 if (e->callee == old_version)
2142 cgraph_redirect_edge_callee (e, new_version);
2147 for (i = 0; VEC_iterate (cgraph_edge_p, redirect_callers, i, e); i++)
2149 /* Redirect calls to the old version node to point to its new
2151 cgraph_redirect_edge_callee (e, new_version);
2157 /* Perform function versioning.
2158 Function versioning includes copying of the tree and
2159 a callgraph update (creating a new cgraph node and updating
2160 its callees and callers).
2162 REDIRECT_CALLERS varray includes the edges to be redirected
2165 TREE_MAP is a mapping of tree nodes we want to replace with
2166 new ones (according to results of prior analysis).
2167 OLD_VERSION_NODE is the node that is versioned.
2168 It returns the new version's cgraph node.
2169 ARGS_TO_SKIP lists arguments to be omitted from functions
2172 struct cgraph_node *
2173 cgraph_function_versioning (struct cgraph_node *old_version_node,
2174 VEC(cgraph_edge_p,heap) *redirect_callers,
2175 VEC (ipa_replace_map_p,gc)* tree_map,
2176 bitmap args_to_skip)
2178 tree old_decl = old_version_node->decl;
2179 struct cgraph_node *new_version_node = NULL;
2182 if (!tree_versionable_function_p (old_decl))
2185 /* Make a new FUNCTION_DECL tree node for the
2188 new_decl = copy_node (old_decl);
2190 new_decl = build_function_decl_skip_args (old_decl, args_to_skip);
2192 /* Create the new version's call-graph node.
2193 and update the edges of the new node. */
2195 cgraph_copy_node_for_versioning (old_version_node, new_decl,
2198 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2199 tree_function_versioning (old_decl, new_decl, tree_map, false, args_to_skip);
2201 /* Update the new version's properties.
2202 Make The new version visible only within this translation unit. Make sure
2203 that is not weak also.
2204 ??? We cannot use COMDAT linkage because there is no
2205 ABI support for this. */
2206 cgraph_make_decl_local (new_version_node->decl);
2207 DECL_VIRTUAL_P (new_version_node->decl) = 0;
2208 new_version_node->local.externally_visible = 0;
2209 new_version_node->local.local = 1;
2210 new_version_node->lowered = true;
2212 /* Update the call_expr on the edges to call the new version node. */
2213 update_call_expr (new_version_node);
2215 cgraph_call_function_insertion_hooks (new_version_node);
2216 return new_version_node;
2219 /* Produce separate function body for inline clones so the offline copy can be
2220 modified without affecting them. */
2221 struct cgraph_node *
2222 save_inline_function_body (struct cgraph_node *node)
2224 struct cgraph_node *first_clone, *n;
2226 gcc_assert (node == cgraph_node (node->decl));
2228 cgraph_lower_function (node);
2230 first_clone = node->clones;
2232 first_clone->decl = copy_node (node->decl);
2233 cgraph_insert_node_to_hashtable (first_clone);
2234 gcc_assert (first_clone == cgraph_node (first_clone->decl));
2235 if (first_clone->next_sibling_clone)
2237 for (n = first_clone->next_sibling_clone; n->next_sibling_clone; n = n->next_sibling_clone)
2238 n->clone_of = first_clone;
2239 n->clone_of = first_clone;
2240 n->next_sibling_clone = first_clone->clones;
2241 if (first_clone->clones)
2242 first_clone->clones->prev_sibling_clone = n;
2243 first_clone->clones = first_clone->next_sibling_clone;
2244 first_clone->next_sibling_clone->prev_sibling_clone = NULL;
2245 first_clone->next_sibling_clone = NULL;
2246 gcc_assert (!first_clone->prev_sibling_clone);
2248 first_clone->clone_of = NULL;
2249 node->clones = NULL;
2251 if (first_clone->clones)
2252 for (n = first_clone->clones; n != first_clone;)
2254 gcc_assert (n->decl == node->decl);
2255 n->decl = first_clone->decl;
2258 else if (n->next_sibling_clone)
2259 n = n->next_sibling_clone;
2262 while (n != first_clone && !n->next_sibling_clone)
2264 if (n != first_clone)
2265 n = n->next_sibling_clone;
2269 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2270 tree_function_versioning (node->decl, first_clone->decl, NULL, true, NULL);
2272 DECL_EXTERNAL (first_clone->decl) = 0;
2273 DECL_COMDAT_GROUP (first_clone->decl) = NULL_TREE;
2274 TREE_PUBLIC (first_clone->decl) = 0;
2275 DECL_COMDAT (first_clone->decl) = 0;
2276 VEC_free (ipa_opt_pass, heap,
2277 first_clone->ipa_transforms_to_apply);
2278 first_clone->ipa_transforms_to_apply = NULL;
2280 #ifdef ENABLE_CHECKING
2281 verify_cgraph_node (first_clone);
2286 /* Given virtual clone, turn it into actual clone. */
2288 cgraph_materialize_clone (struct cgraph_node *node)
2290 bitmap_obstack_initialize (NULL);
2291 /* Copy the OLD_VERSION_NODE function tree to the new version. */
2292 tree_function_versioning (node->clone_of->decl, node->decl,
2293 node->clone.tree_map, true,
2294 node->clone.args_to_skip);
2295 if (cgraph_dump_file)
2297 dump_function_to_file (node->clone_of->decl, cgraph_dump_file, dump_flags);
2298 dump_function_to_file (node->decl, cgraph_dump_file, dump_flags);
2301 /* Function is no longer clone. */
2302 if (node->next_sibling_clone)
2303 node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
2304 if (node->prev_sibling_clone)
2305 node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
2307 node->clone_of->clones = node->next_sibling_clone;
2308 node->next_sibling_clone = NULL;
2309 node->prev_sibling_clone = NULL;
2310 if (!node->clone_of->analyzed && !node->clone_of->clones)
2311 cgraph_remove_node (node->clone_of);
2312 node->clone_of = NULL;
2313 bitmap_obstack_release (NULL);
2316 /* If necessary, change the function declaration in the call statement
2317 associated with E so that it corresponds to the edge callee. */
2320 cgraph_redirect_edge_call_stmt_to_callee (struct cgraph_edge *e)
2322 tree decl = gimple_call_fndecl (e->call_stmt);
2324 gimple_stmt_iterator gsi;
2326 if (!decl || decl == e->callee->decl
2327 /* Don't update call from same body alias to the real function. */
2328 || cgraph_get_node (decl) == cgraph_get_node (e->callee->decl))
2329 return e->call_stmt;
2331 if (cgraph_dump_file)
2333 fprintf (cgraph_dump_file, "updating call of %s/%i -> %s/%i: ",
2334 cgraph_node_name (e->caller), e->caller->uid,
2335 cgraph_node_name (e->callee), e->callee->uid);
2336 print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
2339 if (e->callee->clone.combined_args_to_skip)
2340 new_stmt = gimple_call_copy_skip_args (e->call_stmt,
2341 e->callee->clone.combined_args_to_skip);
2343 new_stmt = e->call_stmt;
2344 if (gimple_vdef (new_stmt)
2345 && TREE_CODE (gimple_vdef (new_stmt)) == SSA_NAME)
2346 SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;
2347 gimple_call_set_fndecl (new_stmt, e->callee->decl);
2349 gsi = gsi_for_stmt (e->call_stmt);
2350 gsi_replace (&gsi, new_stmt, true);
2351 update_stmt (new_stmt);
2353 /* Update EH information too, just in case. */
2354 maybe_clean_or_replace_eh_stmt (e->call_stmt, new_stmt);
2356 cgraph_set_call_stmt_including_clones (e->caller, e->call_stmt, new_stmt);
2358 if (cgraph_dump_file)
2360 fprintf (cgraph_dump_file, " updated to:");
2361 print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
2366 /* Once all functions from compilation unit are in memory, produce all clones
2367 and update all calls. We might also do this on demand if we don't want to
2368 bring all functions to memory prior compilation, but current WHOPR
2369 implementation does that and it is is bit easier to keep everything right in
2372 cgraph_materialize_all_clones (void)
2374 struct cgraph_node *node;
2375 bool stabilized = false;
2377 if (cgraph_dump_file)
2378 fprintf (cgraph_dump_file, "Materializing clones\n");
2379 #ifdef ENABLE_CHECKING
2383 /* We can also do topological order, but number of iterations should be
2384 bounded by number of IPA passes since single IPA pass is probably not
2385 going to create clones of clones it created itself. */
2389 for (node = cgraph_nodes; node; node = node->next)
2391 if (node->clone_of && node->decl != node->clone_of->decl
2392 && !gimple_has_body_p (node->decl))
2394 if (gimple_has_body_p (node->clone_of->decl))
2396 if (cgraph_dump_file)
2398 fprintf (cgraph_dump_file, "clonning %s to %s\n",
2399 cgraph_node_name (node->clone_of),
2400 cgraph_node_name (node));
2401 if (node->clone.tree_map)
2404 fprintf (cgraph_dump_file, " replace map: ");
2405 for (i = 0; i < VEC_length (ipa_replace_map_p,
2406 node->clone.tree_map);
2409 struct ipa_replace_map *replace_info;
2410 replace_info = VEC_index (ipa_replace_map_p,
2411 node->clone.tree_map,
2413 print_generic_expr (cgraph_dump_file, replace_info->old_tree, 0);
2414 fprintf (cgraph_dump_file, " -> ");
2415 print_generic_expr (cgraph_dump_file, replace_info->new_tree, 0);
2416 fprintf (cgraph_dump_file, "%s%s;",
2417 replace_info->replace_p ? "(replace)":"",
2418 replace_info->ref_p ? "(ref)":"");
2420 fprintf (cgraph_dump_file, "\n");
2422 if (node->clone.args_to_skip)
2424 fprintf (cgraph_dump_file, " args_to_skip: ");
2425 dump_bitmap (cgraph_dump_file, node->clone.args_to_skip);
2427 if (node->clone.args_to_skip)
2429 fprintf (cgraph_dump_file, " combined_args_to_skip:");
2430 dump_bitmap (cgraph_dump_file, node->clone.combined_args_to_skip);
2433 cgraph_materialize_clone (node);
2440 for (node = cgraph_nodes; node; node = node->next)
2441 if (!node->analyzed && node->callees)
2442 cgraph_node_remove_callees (node);
2443 if (cgraph_dump_file)
2444 fprintf (cgraph_dump_file, "Updating call sites\n");
2445 for (node = cgraph_nodes; node; node = node->next)
2446 if (node->analyzed && !node->clone_of
2447 && gimple_has_body_p (node->decl))
2449 struct cgraph_edge *e;
2451 current_function_decl = node->decl;
2452 push_cfun (DECL_STRUCT_FUNCTION (node->decl));
2453 for (e = node->callees; e; e = e->next_callee)
2454 cgraph_redirect_edge_call_stmt_to_callee (e);
2455 gcc_assert (!need_ssa_update_p (cfun));
2457 current_function_decl = NULL;
2458 #ifdef ENABLE_CHECKING
2459 verify_cgraph_node (node);
2462 if (cgraph_dump_file)
2463 fprintf (cgraph_dump_file, "Materialization Call site updates done.\n");
2464 /* All changes to parameters have been performed. In order not to
2465 incorrectly repeat them, we simply dispose of the bitmaps that drive the
2467 for (node = cgraph_nodes; node; node = node->next)
2468 node->clone.combined_args_to_skip = NULL;
2469 #ifdef ENABLE_CHECKING
2472 cgraph_remove_unreachable_nodes (false, cgraph_dump_file);
2475 #include "gt-cgraphunit.h"