1443 lines
44 KiB
C
1443 lines
44 KiB
C
/* Basic IPA optimizations and utilities.
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Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
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Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "cgraph.h"
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#include "tree-pass.h"
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#include "timevar.h"
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#include "gimple.h"
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#include "ggc.h"
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#include "flags.h"
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#include "pointer-set.h"
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#include "target.h"
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#include "tree-iterator.h"
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#include "ipa-utils.h"
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/* Look for all functions inlined to NODE and update their inlined_to pointers
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to INLINED_TO. */
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static void
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update_inlined_to_pointer (struct cgraph_node *node, struct cgraph_node *inlined_to)
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{
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struct cgraph_edge *e;
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for (e = node->callees; e; e = e->next_callee)
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if (e->callee->global.inlined_to)
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{
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e->callee->global.inlined_to = inlined_to;
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update_inlined_to_pointer (e->callee, inlined_to);
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}
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}
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/* Add cgraph NODE to queue starting at FIRST.
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The queue is linked via AUX pointers and terminated by pointer to 1.
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We enqueue nodes at two occasions: when we find them reachable or when we find
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their bodies needed for further clonning. In the second case we mark them
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by pointer to 2 after processing so they are re-queue when they become
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reachable. */
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static void
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enqueue_cgraph_node (struct cgraph_node *node, struct cgraph_node **first)
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{
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/* Node is still in queue; do nothing. */
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if (node->aux && node->aux != (void *) 2)
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return;
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/* Node was already processed as unreachable, re-enqueue
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only if it became reachable now. */
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if (node->aux == (void *)2 && !node->reachable)
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return;
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node->aux = *first;
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*first = node;
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}
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/* Add varpool NODE to queue starting at FIRST. */
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static void
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enqueue_varpool_node (struct varpool_node *node, struct varpool_node **first)
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{
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node->aux = *first;
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*first = node;
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}
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/* Process references. */
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static void
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process_references (struct ipa_ref_list *list,
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struct cgraph_node **first,
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struct varpool_node **first_varpool,
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bool before_inlining_p)
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{
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int i;
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struct ipa_ref *ref;
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for (i = 0; ipa_ref_list_reference_iterate (list, i, ref); i++)
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{
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if (ref->refered_type == IPA_REF_CGRAPH)
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{
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struct cgraph_node *node = ipa_ref_node (ref);
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if (!node->reachable
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&& node->analyzed
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&& (!DECL_EXTERNAL (node->decl)
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|| before_inlining_p))
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node->reachable = true;
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enqueue_cgraph_node (node, first);
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}
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else
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{
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struct varpool_node *node = ipa_ref_varpool_node (ref);
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if (!node->needed)
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{
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varpool_mark_needed_node (node);
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enqueue_varpool_node (node, first_varpool);
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}
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}
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}
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}
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/* Return true when NODE can not be local. Worker for cgraph_local_node_p. */
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static bool
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cgraph_non_local_node_p_1 (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED)
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{
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/* FIXME: Aliases can be local, but i386 gets thunks wrong then. */
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return !(cgraph_only_called_directly_or_aliased_p (node)
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&& !ipa_ref_has_aliases_p (&node->ref_list)
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&& node->analyzed
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&& !DECL_EXTERNAL (node->decl)
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&& !node->local.externally_visible
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&& !node->reachable_from_other_partition
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&& !node->in_other_partition);
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}
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/* Return true when function can be marked local. */
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static bool
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cgraph_local_node_p (struct cgraph_node *node)
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{
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struct cgraph_node *n = cgraph_function_or_thunk_node (node, NULL);
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/* FIXME: thunks can be considered local, but we need prevent i386
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from attempting to change calling convention of them. */
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if (n->thunk.thunk_p)
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return false;
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return !cgraph_for_node_and_aliases (n,
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cgraph_non_local_node_p_1, NULL, true);
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}
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/* Return true when NODE has ADDR reference. */
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static bool
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has_addr_references_p (struct cgraph_node *node,
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void *data ATTRIBUTE_UNUSED)
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{
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int i;
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struct ipa_ref *ref;
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for (i = 0; ipa_ref_list_refering_iterate (&node->ref_list, i, ref); i++)
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if (ref->use == IPA_REF_ADDR)
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return true;
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return false;
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}
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/* Perform reachability analysis and reclaim all unreachable nodes.
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If BEFORE_INLINING_P is true this function is called before inlining
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decisions has been made. If BEFORE_INLINING_P is false this function also
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removes unneeded bodies of extern inline functions. */
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bool
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cgraph_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
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{
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struct cgraph_node *first = (struct cgraph_node *) (void *) 1;
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struct varpool_node *first_varpool = (struct varpool_node *) (void *) 1;
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struct cgraph_node *node, *next;
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struct varpool_node *vnode, *vnext;
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bool changed = false;
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#ifdef ENABLE_CHECKING
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verify_cgraph ();
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#endif
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if (file)
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fprintf (file, "\nReclaiming functions:");
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#ifdef ENABLE_CHECKING
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for (node = cgraph_nodes; node; node = node->next)
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gcc_assert (!node->aux);
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for (vnode = varpool_nodes; vnode; vnode = vnode->next)
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gcc_assert (!vnode->aux);
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#endif
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varpool_reset_queue ();
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/* Mark functions whose bodies are obviously needed.
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This is mostly when they can be referenced externally. Inline clones
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are special since their declarations are shared with master clone and thus
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cgraph_can_remove_if_no_direct_calls_and_refs_p should not be called on them. */
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for (node = cgraph_nodes; node; node = node->next)
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if (node->analyzed && !node->global.inlined_to
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&& (!cgraph_can_remove_if_no_direct_calls_and_refs_p (node)
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/* Keep around virtual functions for possible devirtualization. */
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|| (before_inlining_p
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&& DECL_VIRTUAL_P (node->decl)
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&& (DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl)))
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/* Also external functions with address taken are better to stay
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for indirect inlining. */
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|| (before_inlining_p
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&& DECL_EXTERNAL (node->decl)
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&& node->address_taken)))
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{
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gcc_assert (!node->global.inlined_to);
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enqueue_cgraph_node (node, &first);
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node->reachable = true;
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}
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else
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{
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gcc_assert (!node->aux);
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node->reachable = false;
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}
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/* Mark variables that are obviously needed. */
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for (vnode = varpool_nodes; vnode; vnode = vnode->next)
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{
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vnode->next_needed = NULL;
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vnode->prev_needed = NULL;
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if ((vnode->analyzed || vnode->force_output)
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&& !varpool_can_remove_if_no_refs (vnode))
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{
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vnode->needed = false;
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varpool_mark_needed_node (vnode);
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enqueue_varpool_node (vnode, &first_varpool);
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}
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else
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vnode->needed = false;
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}
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/* Perform reachability analysis. As a special case do not consider
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extern inline functions not inlined as live because we won't output
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them at all.
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We maintain two worklist, one for cgraph nodes other for varpools and
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are finished once both are empty. */
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while (first != (struct cgraph_node *) (void *) 1
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|| first_varpool != (struct varpool_node *) (void *) 1)
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{
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if (first != (struct cgraph_node *) (void *) 1)
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{
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struct cgraph_edge *e;
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node = first;
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first = (struct cgraph_node *) first->aux;
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if (!node->reachable)
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node->aux = (void *)2;
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/* If we found this node reachable, first mark on the callees
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reachable too, unless they are direct calls to extern inline functions
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we decided to not inline. */
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if (node->reachable)
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{
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for (e = node->callees; e; e = e->next_callee)
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{
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if (!e->callee->reachable
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&& node->analyzed
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&& (!e->inline_failed
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|| !DECL_EXTERNAL (e->callee->decl)
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|| before_inlining_p))
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e->callee->reachable = true;
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enqueue_cgraph_node (e->callee, &first);
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}
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process_references (&node->ref_list, &first, &first_varpool, before_inlining_p);
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}
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/* If any function in a comdat group is reachable, force
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all other functions in the same comdat group to be
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also reachable. */
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if (node->same_comdat_group
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&& node->reachable
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&& !node->global.inlined_to)
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{
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for (next = node->same_comdat_group;
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next != node;
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next = next->same_comdat_group)
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if (!next->reachable)
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{
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next->reachable = true;
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enqueue_cgraph_node (next, &first);
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}
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}
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/* We can freely remove inline clones even if they are cloned, however if
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function is clone of real clone, we must keep it around in order to
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make materialize_clones produce function body with the changes
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applied. */
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while (node->clone_of && !node->clone_of->aux
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&& !gimple_has_body_p (node->decl))
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{
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bool noninline = node->clone_of->decl != node->decl;
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node = node->clone_of;
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if (noninline && !node->reachable && !node->aux)
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{
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enqueue_cgraph_node (node, &first);
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break;
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}
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}
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}
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if (first_varpool != (struct varpool_node *) (void *) 1)
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{
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vnode = first_varpool;
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first_varpool = (struct varpool_node *)first_varpool->aux;
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vnode->aux = NULL;
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process_references (&vnode->ref_list, &first, &first_varpool, before_inlining_p);
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/* If any function in a comdat group is reachable, force
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all other functions in the same comdat group to be
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also reachable. */
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if (vnode->same_comdat_group)
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{
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struct varpool_node *next;
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for (next = vnode->same_comdat_group;
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next != vnode;
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next = next->same_comdat_group)
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if (!next->needed)
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{
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varpool_mark_needed_node (next);
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enqueue_varpool_node (next, &first_varpool);
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}
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}
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}
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}
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/* Remove unreachable nodes.
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Completely unreachable functions can be fully removed from the callgraph.
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Extern inline functions that we decided to not inline need to become unanalyzed nodes of
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callgraph (so we still have edges to them). We remove function body then.
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Also we need to care functions that are unreachable but we need to keep them around
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for later clonning. In this case we also turn them to unanalyzed nodes, but
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keep the body around. */
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for (node = cgraph_nodes; node; node = next)
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{
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next = node->next;
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if (node->aux && !node->reachable)
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{
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cgraph_node_remove_callees (node);
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ipa_remove_all_references (&node->ref_list);
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node->analyzed = false;
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}
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if (!node->aux)
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{
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struct cgraph_edge *e;
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bool found = false;
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int i;
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struct ipa_ref *ref;
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node->global.inlined_to = NULL;
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if (file)
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fprintf (file, " %s", cgraph_node_name (node));
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/* See if there is reachable caller. */
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for (e = node->callers; e && !found; e = e->next_caller)
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if (e->caller->reachable)
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found = true;
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for (i = 0; (ipa_ref_list_refering_iterate (&node->ref_list, i, ref)
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&& !found); i++)
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if (ref->refering_type == IPA_REF_CGRAPH
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&& ipa_ref_refering_node (ref)->reachable)
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found = true;
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else if (ref->refering_type == IPA_REF_VARPOOL
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&& ipa_ref_refering_varpool_node (ref)->needed)
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found = true;
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/* If so, we need to keep node in the callgraph. */
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if (found)
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{
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if (node->analyzed)
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{
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struct cgraph_node *clone;
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/* If there are still clones, we must keep body around.
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Otherwise we can just remove the body but keep the clone. */
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for (clone = node->clones; clone;
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clone = clone->next_sibling_clone)
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if (clone->aux)
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break;
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if (!clone)
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{
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cgraph_release_function_body (node);
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if (node->prev_sibling_clone)
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node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
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else if (node->clone_of)
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node->clone_of->clones = node->next_sibling_clone;
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if (node->next_sibling_clone)
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node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
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if (node->clone_of)
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node->former_clone_of = node->clone_of->decl;
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node->clone_of = NULL;
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node->next_sibling_clone = NULL;
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node->prev_sibling_clone = NULL;
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}
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else
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gcc_assert (!clone->in_other_partition);
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node->analyzed = false;
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changed = true;
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cgraph_node_remove_callees (node);
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ipa_remove_all_references (&node->ref_list);
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}
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}
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else
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{
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cgraph_remove_node (node);
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changed = true;
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}
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}
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}
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for (node = cgraph_nodes; node; node = node->next)
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{
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/* Inline clones might be kept around so their materializing allows further
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cloning. If the function the clone is inlined into is removed, we need
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to turn it into normal cone. */
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if (node->global.inlined_to
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&& !node->callers)
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{
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gcc_assert (node->clones);
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node->global.inlined_to = NULL;
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update_inlined_to_pointer (node, node);
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}
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node->aux = NULL;
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}
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if (file)
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fprintf (file, "\n");
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/* We must release unused extern inlines or sanity checking will fail. Rest of transformations
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are undesirable at -O0 since we do not want to remove anything. */
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if (!optimize)
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return changed;
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if (file)
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fprintf (file, "Reclaiming variables:");
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for (vnode = varpool_nodes; vnode; vnode = vnext)
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{
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vnext = vnode->next;
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if (!vnode->needed)
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{
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if (file)
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fprintf (file, " %s", varpool_node_name (vnode));
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varpool_remove_node (vnode);
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changed = true;
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}
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}
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/* Now update address_taken flags and try to promote functions to be local. */
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if (file)
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fprintf (file, "\nClearing address taken flags:");
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for (node = cgraph_nodes; node; node = node->next)
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if (node->address_taken
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&& !node->reachable_from_other_partition)
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{
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if (!cgraph_for_node_and_aliases (node, has_addr_references_p, NULL, true))
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{
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if (file)
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fprintf (file, " %s", cgraph_node_name (node));
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node->address_taken = false;
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changed = true;
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if (cgraph_local_node_p (node))
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{
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node->local.local = true;
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if (file)
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fprintf (file, " (local)");
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}
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}
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}
|
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if (file)
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fprintf (file, "\n");
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#ifdef ENABLE_CHECKING
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verify_cgraph ();
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#endif
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/* Reclaim alias pairs for functions that have disappeared from the
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call graph. */
|
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remove_unreachable_alias_pairs ();
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return changed;
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}
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|
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/* Discover variables that have no longer address taken or that are read only
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and update their flags.
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|
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FIXME: This can not be done in between gimplify and omp_expand since
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readonly flag plays role on what is shared and what is not. Currently we do
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this transformation as part of whole program visibility and re-do at
|
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ipa-reference pass (to take into account clonning), but it would
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make sense to do it before early optimizations. */
|
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|
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void
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ipa_discover_readonly_nonaddressable_vars (void)
|
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{
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struct varpool_node *vnode;
|
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if (dump_file)
|
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fprintf (dump_file, "Clearing variable flags:");
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for (vnode = varpool_nodes; vnode; vnode = vnode->next)
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if (vnode->finalized && varpool_all_refs_explicit_p (vnode)
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&& (TREE_ADDRESSABLE (vnode->decl) || !TREE_READONLY (vnode->decl)))
|
|
{
|
|
bool written = false;
|
|
bool address_taken = false;
|
|
int i;
|
|
struct ipa_ref *ref;
|
|
for (i = 0; ipa_ref_list_refering_iterate (&vnode->ref_list, i, ref)
|
|
&& (!written || !address_taken); i++)
|
|
switch (ref->use)
|
|
{
|
|
case IPA_REF_ADDR:
|
|
address_taken = true;
|
|
break;
|
|
case IPA_REF_LOAD:
|
|
break;
|
|
case IPA_REF_STORE:
|
|
written = true;
|
|
break;
|
|
}
|
|
if (TREE_ADDRESSABLE (vnode->decl) && !address_taken)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, " %s (addressable)", varpool_node_name (vnode));
|
|
TREE_ADDRESSABLE (vnode->decl) = 0;
|
|
}
|
|
if (!TREE_READONLY (vnode->decl) && !address_taken && !written
|
|
/* Making variable in explicit section readonly can cause section
|
|
type conflict.
|
|
See e.g. gcc.c-torture/compile/pr23237.c */
|
|
&& DECL_SECTION_NAME (vnode->decl) == NULL)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, " %s (read-only)", varpool_node_name (vnode));
|
|
TREE_READONLY (vnode->decl) = 1;
|
|
}
|
|
}
|
|
if (dump_file)
|
|
fprintf (dump_file, "\n");
|
|
}
|
|
|
|
/* Return true when there is a reference to node and it is not vtable. */
|
|
static bool
|
|
cgraph_address_taken_from_non_vtable_p (struct cgraph_node *node)
|
|
{
|
|
int i;
|
|
struct ipa_ref *ref;
|
|
for (i = 0; ipa_ref_list_refering_iterate (&node->ref_list, i, ref); i++)
|
|
if (ref->use == IPA_REF_ADDR)
|
|
{
|
|
struct varpool_node *node;
|
|
if (ref->refering_type == IPA_REF_CGRAPH)
|
|
return true;
|
|
node = ipa_ref_refering_varpool_node (ref);
|
|
if (!DECL_VIRTUAL_P (node->decl))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/* COMDAT functions must be shared only if they have address taken,
|
|
otherwise we can produce our own private implementation with
|
|
-fwhole-program.
|
|
Return true when turning COMDAT functoin static can not lead to wrong
|
|
code when the resulting object links with a library defining same COMDAT.
|
|
|
|
Virtual functions do have their addresses taken from the vtables,
|
|
but in C++ there is no way to compare their addresses for equality. */
|
|
|
|
bool
|
|
cgraph_comdat_can_be_unshared_p (struct cgraph_node *node)
|
|
{
|
|
if ((cgraph_address_taken_from_non_vtable_p (node)
|
|
&& !DECL_VIRTUAL_P (node->decl))
|
|
|| !node->analyzed)
|
|
return false;
|
|
if (node->same_comdat_group)
|
|
{
|
|
struct cgraph_node *next;
|
|
|
|
/* If more than one function is in the same COMDAT group, it must
|
|
be shared even if just one function in the comdat group has
|
|
address taken. */
|
|
for (next = node->same_comdat_group;
|
|
next != node; next = next->same_comdat_group)
|
|
if (cgraph_address_taken_from_non_vtable_p (next)
|
|
&& !DECL_VIRTUAL_P (next->decl))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/* Return true when function NODE should be considered externally visible. */
|
|
|
|
static bool
|
|
cgraph_externally_visible_p (struct cgraph_node *node,
|
|
bool whole_program, bool aliased)
|
|
{
|
|
if (!node->local.finalized)
|
|
return false;
|
|
if (!DECL_COMDAT (node->decl)
|
|
&& (!TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl)))
|
|
return false;
|
|
|
|
/* Do not even try to be smart about aliased nodes. Until we properly
|
|
represent everything by same body alias, these are just evil. */
|
|
if (aliased)
|
|
return true;
|
|
|
|
/* Do not try to localize built-in functions yet. One of problems is that we
|
|
end up mangling their asm for WHOPR that makes it impossible to call them
|
|
using the implicit built-in declarations anymore. Similarly this enables
|
|
us to remove them as unreachable before actual calls may appear during
|
|
expansion or folding. */
|
|
if (DECL_BUILT_IN (node->decl))
|
|
return true;
|
|
|
|
/* If linker counts on us, we must preserve the function. */
|
|
if (cgraph_used_from_object_file_p (node))
|
|
return true;
|
|
if (DECL_PRESERVE_P (node->decl))
|
|
return true;
|
|
if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (node->decl)))
|
|
return true;
|
|
if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
|
|
&& lookup_attribute ("dllexport", DECL_ATTRIBUTES (node->decl)))
|
|
return true;
|
|
if (node->resolution == LDPR_PREVAILING_DEF_IRONLY)
|
|
return false;
|
|
/* When doing LTO or whole program, we can bring COMDAT functoins static.
|
|
This improves code quality and we know we will duplicate them at most twice
|
|
(in the case that we are not using plugin and link with object file
|
|
implementing same COMDAT) */
|
|
if ((in_lto_p || whole_program)
|
|
&& DECL_COMDAT (node->decl)
|
|
&& cgraph_comdat_can_be_unshared_p (node))
|
|
return false;
|
|
|
|
/* When doing link time optimizations, hidden symbols become local. */
|
|
if (in_lto_p
|
|
&& (DECL_VISIBILITY (node->decl) == VISIBILITY_HIDDEN
|
|
|| DECL_VISIBILITY (node->decl) == VISIBILITY_INTERNAL)
|
|
/* Be sure that node is defined in IR file, not in other object
|
|
file. In that case we don't set used_from_other_object_file. */
|
|
&& node->analyzed)
|
|
;
|
|
else if (!whole_program)
|
|
return true;
|
|
|
|
if (MAIN_NAME_P (DECL_NAME (node->decl)))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/* Return true when variable VNODE should be considered externally visible. */
|
|
|
|
static bool
|
|
varpool_externally_visible_p (struct varpool_node *vnode, bool aliased)
|
|
{
|
|
if (!DECL_COMDAT (vnode->decl) && !TREE_PUBLIC (vnode->decl))
|
|
return false;
|
|
|
|
/* Do not even try to be smart about aliased nodes. Until we properly
|
|
represent everything by same body alias, these are just evil. */
|
|
if (aliased)
|
|
return true;
|
|
|
|
/* If linker counts on us, we must preserve the function. */
|
|
if (varpool_used_from_object_file_p (vnode))
|
|
return true;
|
|
|
|
if (DECL_PRESERVE_P (vnode->decl))
|
|
return true;
|
|
if (lookup_attribute ("externally_visible",
|
|
DECL_ATTRIBUTES (vnode->decl)))
|
|
return true;
|
|
if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
|
|
&& lookup_attribute ("dllexport",
|
|
DECL_ATTRIBUTES (vnode->decl)))
|
|
return true;
|
|
|
|
/* See if we have linker information about symbol not being used or
|
|
if we need to make guess based on the declaration.
|
|
|
|
Even if the linker clams the symbol is unused, never bring internal
|
|
symbols that are declared by user as used or externally visible.
|
|
This is needed for i.e. references from asm statements. */
|
|
if (varpool_used_from_object_file_p (vnode))
|
|
return true;
|
|
|
|
/* As a special case, the COMDAT virutal tables can be unshared.
|
|
In LTO mode turn vtables into static variables. The variable is readonly,
|
|
so this does not enable more optimization, but referring static var
|
|
is faster for dynamic linking. Also this match logic hidding vtables
|
|
from LTO symbol tables. */
|
|
if ((in_lto_p || flag_whole_program)
|
|
&& !vnode->force_output
|
|
&& DECL_COMDAT (vnode->decl) && DECL_VIRTUAL_P (vnode->decl))
|
|
return false;
|
|
|
|
/* When doing link time optimizations, hidden symbols become local. */
|
|
if (in_lto_p
|
|
&& (DECL_VISIBILITY (vnode->decl) == VISIBILITY_HIDDEN
|
|
|| DECL_VISIBILITY (vnode->decl) == VISIBILITY_INTERNAL)
|
|
/* Be sure that node is defined in IR file, not in other object
|
|
file. In that case we don't set used_from_other_object_file. */
|
|
&& vnode->finalized)
|
|
;
|
|
else if (!flag_whole_program)
|
|
return true;
|
|
|
|
/* Do not attempt to privatize COMDATS by default.
|
|
This would break linking with C++ libraries sharing
|
|
inline definitions.
|
|
|
|
FIXME: We can do so for readonly vars with no address taken and
|
|
possibly also for vtables since no direct pointer comparsion is done.
|
|
It might be interesting to do so to reduce linking overhead. */
|
|
if (DECL_COMDAT (vnode->decl) || DECL_WEAK (vnode->decl))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/* Dissolve the same_comdat_group list in which NODE resides. */
|
|
|
|
static void
|
|
dissolve_same_comdat_group_list (struct cgraph_node *node)
|
|
{
|
|
struct cgraph_node *n = node, *next;
|
|
do
|
|
{
|
|
next = n->same_comdat_group;
|
|
n->same_comdat_group = NULL;
|
|
n = next;
|
|
}
|
|
while (n != node);
|
|
}
|
|
|
|
/* Mark visibility of all functions.
|
|
|
|
A local function is one whose calls can occur only in the current
|
|
compilation unit and all its calls are explicit, so we can change
|
|
its calling convention. We simply mark all static functions whose
|
|
address is not taken as local.
|
|
|
|
We also change the TREE_PUBLIC flag of all declarations that are public
|
|
in language point of view but we want to overwrite this default
|
|
via visibilities for the backend point of view. */
|
|
|
|
static unsigned int
|
|
function_and_variable_visibility (bool whole_program)
|
|
{
|
|
struct cgraph_node *node;
|
|
struct varpool_node *vnode;
|
|
struct pointer_set_t *aliased_nodes = pointer_set_create ();
|
|
struct pointer_set_t *aliased_vnodes = pointer_set_create ();
|
|
unsigned i;
|
|
alias_pair *p;
|
|
|
|
/* Discover aliased nodes. */
|
|
FOR_EACH_VEC_ELT (alias_pair, alias_pairs, i, p)
|
|
{
|
|
if (dump_file)
|
|
fprintf (dump_file, "Alias %s->%s",
|
|
IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (p->decl)),
|
|
IDENTIFIER_POINTER (p->target));
|
|
|
|
if ((node = cgraph_node_for_asm (p->target)) != NULL
|
|
&& !DECL_EXTERNAL (node->decl))
|
|
{
|
|
if (!node->analyzed)
|
|
continue;
|
|
cgraph_mark_needed_node (node);
|
|
gcc_assert (node->needed);
|
|
pointer_set_insert (aliased_nodes, node);
|
|
if (dump_file)
|
|
fprintf (dump_file, " node %s/%i",
|
|
cgraph_node_name (node), node->uid);
|
|
}
|
|
else if ((vnode = varpool_node_for_asm (p->target)) != NULL
|
|
&& !DECL_EXTERNAL (vnode->decl))
|
|
{
|
|
varpool_mark_needed_node (vnode);
|
|
gcc_assert (vnode->needed);
|
|
pointer_set_insert (aliased_vnodes, vnode);
|
|
if (dump_file)
|
|
fprintf (dump_file, " varpool node %s",
|
|
varpool_node_name (vnode));
|
|
}
|
|
if (dump_file)
|
|
fprintf (dump_file, "\n");
|
|
}
|
|
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
{
|
|
int flags = flags_from_decl_or_type (node->decl);
|
|
|
|
/* Optimize away PURE and CONST constructors and destructors. */
|
|
if (optimize
|
|
&& (flags & (ECF_CONST | ECF_PURE))
|
|
&& !(flags & ECF_LOOPING_CONST_OR_PURE))
|
|
{
|
|
DECL_STATIC_CONSTRUCTOR (node->decl) = 0;
|
|
DECL_STATIC_DESTRUCTOR (node->decl) = 0;
|
|
}
|
|
|
|
/* Frontends and alias code marks nodes as needed before parsing is finished.
|
|
We may end up marking as node external nodes where this flag is meaningless
|
|
strip it. */
|
|
if (node->needed
|
|
&& (DECL_EXTERNAL (node->decl) || !node->analyzed))
|
|
node->needed = 0;
|
|
|
|
/* C++ FE on lack of COMDAT support create local COMDAT functions
|
|
(that ought to be shared but can not due to object format
|
|
limitations). It is neccesary to keep the flag to make rest of C++ FE
|
|
happy. Clear the flag here to avoid confusion in middle-end. */
|
|
if (DECL_COMDAT (node->decl) && !TREE_PUBLIC (node->decl))
|
|
DECL_COMDAT (node->decl) = 0;
|
|
/* For external decls stop tracking same_comdat_group, it doesn't matter
|
|
what comdat group they are in when they won't be emitted in this TU,
|
|
and simplifies later passes. */
|
|
if (node->same_comdat_group && DECL_EXTERNAL (node->decl))
|
|
{
|
|
#ifdef ENABLE_CHECKING
|
|
struct cgraph_node *n;
|
|
|
|
for (n = node->same_comdat_group;
|
|
n != node;
|
|
n = n->same_comdat_group)
|
|
/* If at least one of same comdat group functions is external,
|
|
all of them have to be, otherwise it is a front-end bug. */
|
|
gcc_assert (DECL_EXTERNAL (n->decl));
|
|
#endif
|
|
dissolve_same_comdat_group_list (node);
|
|
}
|
|
gcc_assert ((!DECL_WEAK (node->decl) && !DECL_COMDAT (node->decl))
|
|
|| TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl));
|
|
if (cgraph_externally_visible_p (node, whole_program,
|
|
pointer_set_contains (aliased_nodes,
|
|
node)))
|
|
{
|
|
gcc_assert (!node->global.inlined_to);
|
|
node->local.externally_visible = true;
|
|
}
|
|
else
|
|
node->local.externally_visible = false;
|
|
if (!node->local.externally_visible && node->analyzed
|
|
&& !DECL_EXTERNAL (node->decl))
|
|
{
|
|
gcc_assert (whole_program || in_lto_p || !TREE_PUBLIC (node->decl));
|
|
cgraph_make_decl_local (node->decl);
|
|
node->resolution = LDPR_PREVAILING_DEF_IRONLY;
|
|
if (node->same_comdat_group)
|
|
/* cgraph_externally_visible_p has already checked all other nodes
|
|
in the group and they will all be made local. We need to
|
|
dissolve the group at once so that the predicate does not
|
|
segfault though. */
|
|
dissolve_same_comdat_group_list (node);
|
|
}
|
|
|
|
if (node->thunk.thunk_p
|
|
&& TREE_PUBLIC (node->decl))
|
|
{
|
|
struct cgraph_node *decl_node = node;
|
|
|
|
decl_node = cgraph_function_node (decl_node->callees->callee, NULL);
|
|
|
|
/* Thunks have the same visibility as function they are attached to.
|
|
Make sure the C++ front end set this up properly. */
|
|
if (DECL_ONE_ONLY (decl_node->decl))
|
|
{
|
|
gcc_checking_assert (DECL_COMDAT (node->decl)
|
|
== DECL_COMDAT (decl_node->decl));
|
|
gcc_checking_assert (DECL_COMDAT_GROUP (node->decl)
|
|
== DECL_COMDAT_GROUP (decl_node->decl));
|
|
gcc_checking_assert (node->same_comdat_group);
|
|
}
|
|
if (DECL_EXTERNAL (decl_node->decl))
|
|
DECL_EXTERNAL (node->decl) = 1;
|
|
}
|
|
}
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
node->local.local = cgraph_local_node_p (node);
|
|
for (vnode = varpool_nodes; vnode; vnode = vnode->next)
|
|
{
|
|
/* weak flag makes no sense on local variables. */
|
|
gcc_assert (!DECL_WEAK (vnode->decl)
|
|
|| TREE_PUBLIC (vnode->decl) || DECL_EXTERNAL (vnode->decl));
|
|
/* In several cases declarations can not be common:
|
|
|
|
- when declaration has initializer
|
|
- when it is in weak
|
|
- when it has specific section
|
|
- when it resides in non-generic address space.
|
|
- if declaration is local, it will get into .local common section
|
|
so common flag is not needed. Frontends still produce these in
|
|
certain cases, such as for:
|
|
|
|
static int a __attribute__ ((common))
|
|
|
|
Canonicalize things here and clear the redundant flag. */
|
|
if (DECL_COMMON (vnode->decl)
|
|
&& (!(TREE_PUBLIC (vnode->decl) || DECL_EXTERNAL (vnode->decl))
|
|
|| (DECL_INITIAL (vnode->decl)
|
|
&& DECL_INITIAL (vnode->decl) != error_mark_node)
|
|
|| DECL_WEAK (vnode->decl)
|
|
|| DECL_SECTION_NAME (vnode->decl) != NULL
|
|
|| ! (ADDR_SPACE_GENERIC_P
|
|
(TYPE_ADDR_SPACE (TREE_TYPE (vnode->decl))))))
|
|
DECL_COMMON (vnode->decl) = 0;
|
|
}
|
|
for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
|
|
{
|
|
if (!vnode->finalized)
|
|
continue;
|
|
if (vnode->needed
|
|
&& varpool_externally_visible_p
|
|
(vnode,
|
|
pointer_set_contains (aliased_vnodes, vnode)))
|
|
vnode->externally_visible = true;
|
|
else
|
|
vnode->externally_visible = false;
|
|
if (!vnode->externally_visible)
|
|
{
|
|
gcc_assert (in_lto_p || whole_program || !TREE_PUBLIC (vnode->decl));
|
|
cgraph_make_decl_local (vnode->decl);
|
|
vnode->resolution = LDPR_PREVAILING_DEF_IRONLY;
|
|
}
|
|
gcc_assert (TREE_STATIC (vnode->decl));
|
|
}
|
|
pointer_set_destroy (aliased_nodes);
|
|
pointer_set_destroy (aliased_vnodes);
|
|
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file, "\nMarking local functions:");
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
if (node->local.local)
|
|
fprintf (dump_file, " %s", cgraph_node_name (node));
|
|
fprintf (dump_file, "\n\n");
|
|
fprintf (dump_file, "\nMarking externally visible functions:");
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
if (node->local.externally_visible)
|
|
fprintf (dump_file, " %s", cgraph_node_name (node));
|
|
fprintf (dump_file, "\n\n");
|
|
fprintf (dump_file, "\nMarking externally visible variables:");
|
|
for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
|
|
if (vnode->externally_visible)
|
|
fprintf (dump_file, " %s", varpool_node_name (vnode));
|
|
fprintf (dump_file, "\n\n");
|
|
}
|
|
cgraph_function_flags_ready = true;
|
|
return 0;
|
|
}
|
|
|
|
/* Local function pass handling visibilities. This happens before LTO streaming
|
|
so in particular -fwhole-program should be ignored at this level. */
|
|
|
|
static unsigned int
|
|
local_function_and_variable_visibility (void)
|
|
{
|
|
return function_and_variable_visibility (flag_whole_program && !flag_lto);
|
|
}
|
|
|
|
struct simple_ipa_opt_pass pass_ipa_function_and_variable_visibility =
|
|
{
|
|
{
|
|
SIMPLE_IPA_PASS,
|
|
"visibility", /* name */
|
|
NULL, /* gate */
|
|
local_function_and_variable_visibility,/* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_CGRAPHOPT, /* tv_id */
|
|
0, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
0, /* todo_flags_start */
|
|
TODO_remove_functions | TODO_dump_cgraph
|
|
| TODO_ggc_collect /* todo_flags_finish */
|
|
}
|
|
};
|
|
|
|
/* Do not re-run on ltrans stage. */
|
|
|
|
static bool
|
|
gate_whole_program_function_and_variable_visibility (void)
|
|
{
|
|
return !flag_ltrans;
|
|
}
|
|
|
|
/* Bring functionss local at LTO time whith -fwhole-program. */
|
|
|
|
static unsigned int
|
|
whole_program_function_and_variable_visibility (void)
|
|
{
|
|
struct cgraph_node *node;
|
|
struct varpool_node *vnode;
|
|
|
|
function_and_variable_visibility (flag_whole_program);
|
|
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
if ((node->local.externally_visible && !DECL_COMDAT (node->decl))
|
|
&& node->local.finalized)
|
|
cgraph_mark_needed_node (node);
|
|
for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
|
|
if (vnode->externally_visible && !DECL_COMDAT (vnode->decl))
|
|
varpool_mark_needed_node (vnode);
|
|
if (dump_file)
|
|
{
|
|
fprintf (dump_file, "\nNeeded variables:");
|
|
for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
|
|
if (vnode->needed)
|
|
fprintf (dump_file, " %s", varpool_node_name (vnode));
|
|
fprintf (dump_file, "\n\n");
|
|
}
|
|
if (optimize)
|
|
ipa_discover_readonly_nonaddressable_vars ();
|
|
return 0;
|
|
}
|
|
|
|
struct ipa_opt_pass_d pass_ipa_whole_program_visibility =
|
|
{
|
|
{
|
|
IPA_PASS,
|
|
"whole-program", /* name */
|
|
gate_whole_program_function_and_variable_visibility,/* gate */
|
|
whole_program_function_and_variable_visibility,/* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_CGRAPHOPT, /* tv_id */
|
|
0, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
0, /* todo_flags_start */
|
|
TODO_remove_functions | TODO_dump_cgraph
|
|
| TODO_ggc_collect /* todo_flags_finish */
|
|
},
|
|
NULL, /* generate_summary */
|
|
NULL, /* write_summary */
|
|
NULL, /* read_summary */
|
|
NULL, /* write_optimization_summary */
|
|
NULL, /* read_optimization_summary */
|
|
NULL, /* stmt_fixup */
|
|
0, /* TODOs */
|
|
NULL, /* function_transform */
|
|
NULL, /* variable_transform */
|
|
};
|
|
|
|
|
|
/* Simple ipa profile pass propagating frequencies across the callgraph. */
|
|
|
|
static unsigned int
|
|
ipa_profile (void)
|
|
{
|
|
struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
|
|
struct cgraph_edge *e;
|
|
int order_pos;
|
|
bool something_changed = false;
|
|
int i;
|
|
|
|
order_pos = ipa_reverse_postorder (order);
|
|
for (i = order_pos - 1; i >= 0; i--)
|
|
{
|
|
if (order[i]->local.local && cgraph_propagate_frequency (order[i]))
|
|
{
|
|
for (e = order[i]->callees; e; e = e->next_callee)
|
|
if (e->callee->local.local && !e->callee->aux)
|
|
{
|
|
something_changed = true;
|
|
e->callee->aux = (void *)1;
|
|
}
|
|
}
|
|
order[i]->aux = NULL;
|
|
}
|
|
|
|
while (something_changed)
|
|
{
|
|
something_changed = false;
|
|
for (i = order_pos - 1; i >= 0; i--)
|
|
{
|
|
if (order[i]->aux && cgraph_propagate_frequency (order[i]))
|
|
{
|
|
for (e = order[i]->callees; e; e = e->next_callee)
|
|
if (e->callee->local.local && !e->callee->aux)
|
|
{
|
|
something_changed = true;
|
|
e->callee->aux = (void *)1;
|
|
}
|
|
}
|
|
order[i]->aux = NULL;
|
|
}
|
|
}
|
|
free (order);
|
|
return 0;
|
|
}
|
|
|
|
static bool
|
|
gate_ipa_profile (void)
|
|
{
|
|
return flag_ipa_profile;
|
|
}
|
|
|
|
struct ipa_opt_pass_d pass_ipa_profile =
|
|
{
|
|
{
|
|
IPA_PASS,
|
|
"profile_estimate", /* name */
|
|
gate_ipa_profile, /* gate */
|
|
ipa_profile, /* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_IPA_PROFILE, /* tv_id */
|
|
0, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
0, /* todo_flags_start */
|
|
0 /* todo_flags_finish */
|
|
},
|
|
NULL, /* generate_summary */
|
|
NULL, /* write_summary */
|
|
NULL, /* read_summary */
|
|
NULL, /* write_optimization_summary */
|
|
NULL, /* read_optimization_summary */
|
|
NULL, /* stmt_fixup */
|
|
0, /* TODOs */
|
|
NULL, /* function_transform */
|
|
NULL /* variable_transform */
|
|
};
|
|
|
|
/* Generate and emit a static constructor or destructor. WHICH must
|
|
be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
|
|
is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
|
|
initialization priority for this constructor or destructor.
|
|
|
|
FINAL specify whether the externally visible name for collect2 should
|
|
be produced. */
|
|
|
|
static void
|
|
cgraph_build_static_cdtor_1 (char which, tree body, int priority, bool final)
|
|
{
|
|
static int counter = 0;
|
|
char which_buf[16];
|
|
tree decl, name, resdecl;
|
|
|
|
/* The priority is encoded in the constructor or destructor name.
|
|
collect2 will sort the names and arrange that they are called at
|
|
program startup. */
|
|
if (final)
|
|
sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
|
|
else
|
|
/* Proudce sane name but one not recognizable by collect2, just for the
|
|
case we fail to inline the function. */
|
|
sprintf (which_buf, "sub_%c_%.5d_%d", which, priority, counter++);
|
|
name = get_file_function_name (which_buf);
|
|
|
|
decl = build_decl (input_location, FUNCTION_DECL, name,
|
|
build_function_type_list (void_type_node, NULL_TREE));
|
|
current_function_decl = decl;
|
|
|
|
resdecl = build_decl (input_location,
|
|
RESULT_DECL, NULL_TREE, void_type_node);
|
|
DECL_ARTIFICIAL (resdecl) = 1;
|
|
DECL_RESULT (decl) = resdecl;
|
|
DECL_CONTEXT (resdecl) = decl;
|
|
|
|
allocate_struct_function (decl, false);
|
|
|
|
TREE_STATIC (decl) = 1;
|
|
TREE_USED (decl) = 1;
|
|
DECL_ARTIFICIAL (decl) = 1;
|
|
DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
|
|
DECL_SAVED_TREE (decl) = body;
|
|
if (!targetm.have_ctors_dtors && final)
|
|
{
|
|
TREE_PUBLIC (decl) = 1;
|
|
DECL_PRESERVE_P (decl) = 1;
|
|
}
|
|
DECL_UNINLINABLE (decl) = 1;
|
|
|
|
DECL_INITIAL (decl) = make_node (BLOCK);
|
|
TREE_USED (DECL_INITIAL (decl)) = 1;
|
|
|
|
DECL_SOURCE_LOCATION (decl) = input_location;
|
|
cfun->function_end_locus = input_location;
|
|
|
|
switch (which)
|
|
{
|
|
case 'I':
|
|
DECL_STATIC_CONSTRUCTOR (decl) = 1;
|
|
decl_init_priority_insert (decl, priority);
|
|
break;
|
|
case 'D':
|
|
DECL_STATIC_DESTRUCTOR (decl) = 1;
|
|
decl_fini_priority_insert (decl, priority);
|
|
break;
|
|
default:
|
|
gcc_unreachable ();
|
|
}
|
|
|
|
gimplify_function_tree (decl);
|
|
|
|
cgraph_add_new_function (decl, false);
|
|
|
|
set_cfun (NULL);
|
|
current_function_decl = NULL;
|
|
}
|
|
|
|
/* Generate and emit a static constructor or destructor. WHICH must
|
|
be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
|
|
is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
|
|
initialization priority for this constructor or destructor. */
|
|
|
|
void
|
|
cgraph_build_static_cdtor (char which, tree body, int priority)
|
|
{
|
|
cgraph_build_static_cdtor_1 (which, body, priority, false);
|
|
}
|
|
|
|
/* A vector of FUNCTION_DECLs declared as static constructors. */
|
|
static VEC(tree, heap) *static_ctors;
|
|
/* A vector of FUNCTION_DECLs declared as static destructors. */
|
|
static VEC(tree, heap) *static_dtors;
|
|
|
|
/* When target does not have ctors and dtors, we call all constructor
|
|
and destructor by special initialization/destruction function
|
|
recognized by collect2.
|
|
|
|
When we are going to build this function, collect all constructors and
|
|
destructors and turn them into normal functions. */
|
|
|
|
static void
|
|
record_cdtor_fn (struct cgraph_node *node)
|
|
{
|
|
if (DECL_STATIC_CONSTRUCTOR (node->decl))
|
|
VEC_safe_push (tree, heap, static_ctors, node->decl);
|
|
if (DECL_STATIC_DESTRUCTOR (node->decl))
|
|
VEC_safe_push (tree, heap, static_dtors, node->decl);
|
|
node = cgraph_get_node (node->decl);
|
|
DECL_DISREGARD_INLINE_LIMITS (node->decl) = 1;
|
|
}
|
|
|
|
/* Define global constructors/destructor functions for the CDTORS, of
|
|
which they are LEN. The CDTORS are sorted by initialization
|
|
priority. If CTOR_P is true, these are constructors; otherwise,
|
|
they are destructors. */
|
|
|
|
static void
|
|
build_cdtor (bool ctor_p, VEC (tree, heap) *cdtors)
|
|
{
|
|
size_t i,j;
|
|
size_t len = VEC_length (tree, cdtors);
|
|
|
|
i = 0;
|
|
while (i < len)
|
|
{
|
|
tree body;
|
|
tree fn;
|
|
priority_type priority;
|
|
|
|
priority = 0;
|
|
body = NULL_TREE;
|
|
j = i;
|
|
do
|
|
{
|
|
priority_type p;
|
|
fn = VEC_index (tree, cdtors, j);
|
|
p = ctor_p ? DECL_INIT_PRIORITY (fn) : DECL_FINI_PRIORITY (fn);
|
|
if (j == i)
|
|
priority = p;
|
|
else if (p != priority)
|
|
break;
|
|
j++;
|
|
}
|
|
while (j < len);
|
|
|
|
/* When there is only one cdtor and target supports them, do nothing. */
|
|
if (j == i + 1
|
|
&& targetm.have_ctors_dtors)
|
|
{
|
|
i++;
|
|
continue;
|
|
}
|
|
/* Find the next batch of constructors/destructors with the same
|
|
initialization priority. */
|
|
for (;i < j; i++)
|
|
{
|
|
tree call;
|
|
fn = VEC_index (tree, cdtors, i);
|
|
call = build_call_expr (fn, 0);
|
|
if (ctor_p)
|
|
DECL_STATIC_CONSTRUCTOR (fn) = 0;
|
|
else
|
|
DECL_STATIC_DESTRUCTOR (fn) = 0;
|
|
/* We do not want to optimize away pure/const calls here.
|
|
When optimizing, these should be already removed, when not
|
|
optimizing, we want user to be able to breakpoint in them. */
|
|
TREE_SIDE_EFFECTS (call) = 1;
|
|
append_to_statement_list (call, &body);
|
|
}
|
|
gcc_assert (body != NULL_TREE);
|
|
/* Generate a function to call all the function of like
|
|
priority. */
|
|
cgraph_build_static_cdtor_1 (ctor_p ? 'I' : 'D', body, priority, true);
|
|
}
|
|
}
|
|
|
|
/* Comparison function for qsort. P1 and P2 are actually of type
|
|
"tree *" and point to static constructors. DECL_INIT_PRIORITY is
|
|
used to determine the sort order. */
|
|
|
|
static int
|
|
compare_ctor (const void *p1, const void *p2)
|
|
{
|
|
tree f1;
|
|
tree f2;
|
|
int priority1;
|
|
int priority2;
|
|
|
|
f1 = *(const tree *)p1;
|
|
f2 = *(const tree *)p2;
|
|
priority1 = DECL_INIT_PRIORITY (f1);
|
|
priority2 = DECL_INIT_PRIORITY (f2);
|
|
|
|
if (priority1 < priority2)
|
|
return -1;
|
|
else if (priority1 > priority2)
|
|
return 1;
|
|
else
|
|
/* Ensure a stable sort. Constructors are executed in backwarding
|
|
order to make LTO initialize braries first. */
|
|
return DECL_UID (f2) - DECL_UID (f1);
|
|
}
|
|
|
|
/* Comparison function for qsort. P1 and P2 are actually of type
|
|
"tree *" and point to static destructors. DECL_FINI_PRIORITY is
|
|
used to determine the sort order. */
|
|
|
|
static int
|
|
compare_dtor (const void *p1, const void *p2)
|
|
{
|
|
tree f1;
|
|
tree f2;
|
|
int priority1;
|
|
int priority2;
|
|
|
|
f1 = *(const tree *)p1;
|
|
f2 = *(const tree *)p2;
|
|
priority1 = DECL_FINI_PRIORITY (f1);
|
|
priority2 = DECL_FINI_PRIORITY (f2);
|
|
|
|
if (priority1 < priority2)
|
|
return -1;
|
|
else if (priority1 > priority2)
|
|
return 1;
|
|
else
|
|
/* Ensure a stable sort. */
|
|
return DECL_UID (f1) - DECL_UID (f2);
|
|
}
|
|
|
|
/* Generate functions to call static constructors and destructors
|
|
for targets that do not support .ctors/.dtors sections. These
|
|
functions have magic names which are detected by collect2. */
|
|
|
|
static void
|
|
build_cdtor_fns (void)
|
|
{
|
|
if (!VEC_empty (tree, static_ctors))
|
|
{
|
|
gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
|
|
VEC_qsort (tree, static_ctors, compare_ctor);
|
|
build_cdtor (/*ctor_p=*/true, static_ctors);
|
|
}
|
|
|
|
if (!VEC_empty (tree, static_dtors))
|
|
{
|
|
gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
|
|
VEC_qsort (tree, static_dtors, compare_dtor);
|
|
build_cdtor (/*ctor_p=*/false, static_dtors);
|
|
}
|
|
}
|
|
|
|
/* Look for constructors and destructors and produce function calling them.
|
|
This is needed for targets not supporting ctors or dtors, but we perform the
|
|
transformation also at linktime to merge possibly numberous
|
|
constructors/destructors into single function to improve code locality and
|
|
reduce size. */
|
|
|
|
static unsigned int
|
|
ipa_cdtor_merge (void)
|
|
{
|
|
struct cgraph_node *node;
|
|
for (node = cgraph_nodes; node; node = node->next)
|
|
if (node->analyzed
|
|
&& (DECL_STATIC_CONSTRUCTOR (node->decl)
|
|
|| DECL_STATIC_DESTRUCTOR (node->decl)))
|
|
record_cdtor_fn (node);
|
|
build_cdtor_fns ();
|
|
VEC_free (tree, heap, static_ctors);
|
|
VEC_free (tree, heap, static_dtors);
|
|
return 0;
|
|
}
|
|
|
|
/* Perform the pass when we have no ctors/dtors support
|
|
or at LTO time to merge multiple constructors into single
|
|
function. */
|
|
|
|
static bool
|
|
gate_ipa_cdtor_merge (void)
|
|
{
|
|
return !targetm.have_ctors_dtors || (optimize && in_lto_p);
|
|
}
|
|
|
|
struct ipa_opt_pass_d pass_ipa_cdtor_merge =
|
|
{
|
|
{
|
|
IPA_PASS,
|
|
"cdtor", /* name */
|
|
gate_ipa_cdtor_merge, /* gate */
|
|
ipa_cdtor_merge, /* execute */
|
|
NULL, /* sub */
|
|
NULL, /* next */
|
|
0, /* static_pass_number */
|
|
TV_CGRAPHOPT, /* tv_id */
|
|
0, /* properties_required */
|
|
0, /* properties_provided */
|
|
0, /* properties_destroyed */
|
|
0, /* todo_flags_start */
|
|
0 /* todo_flags_finish */
|
|
},
|
|
NULL, /* generate_summary */
|
|
NULL, /* write_summary */
|
|
NULL, /* read_summary */
|
|
NULL, /* write_optimization_summary */
|
|
NULL, /* read_optimization_summary */
|
|
NULL, /* stmt_fixup */
|
|
0, /* TODOs */
|
|
NULL, /* function_transform */
|
|
NULL /* variable_transform */
|
|
};
|