/* Callgraph handling code.
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/* Callgraph handling code.
|
Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2010
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Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2010
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Free Software Foundation, Inc.
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Free Software Foundation, Inc.
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Contributed by Jan Hubicka
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Contributed by Jan Hubicka
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This file is part of GCC.
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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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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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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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Software Foundation; either version 3, or (at your option) any later
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version.
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version.
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|
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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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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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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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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for more details.
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|
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You should have received a copy of the GNU General Public License
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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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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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<http://www.gnu.org/licenses/>. */
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#include "config.h"
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#include "config.h"
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#include "system.h"
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#include "system.h"
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#include "coretypes.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "tm.h"
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#include "tree.h"
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#include "tree.h"
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#include "cgraph.h"
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#include "cgraph.h"
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#include "langhooks.h"
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#include "langhooks.h"
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#include "diagnostic.h"
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#include "diagnostic.h"
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#include "hashtab.h"
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#include "hashtab.h"
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#include "ggc.h"
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#include "ggc.h"
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#include "timevar.h"
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#include "timevar.h"
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#include "debug.h"
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#include "debug.h"
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#include "target.h"
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#include "target.h"
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#include "output.h"
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#include "output.h"
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#include "gimple.h"
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#include "gimple.h"
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#include "tree-flow.h"
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#include "tree-flow.h"
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#include "flags.h"
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#include "flags.h"
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/* This file contains basic routines manipulating variable pool.
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/* This file contains basic routines manipulating variable pool.
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|
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Varpool acts as interface in between the front-end and middle-end
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Varpool acts as interface in between the front-end and middle-end
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and drives the decision process on what variables and when are
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and drives the decision process on what variables and when are
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going to be compiled.
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going to be compiled.
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|
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The varpool nodes are allocated lazily for declarations
|
The varpool nodes are allocated lazily for declarations
|
either by frontend or at callgraph construction time.
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either by frontend or at callgraph construction time.
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All variables supposed to be output into final file needs to be
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All variables supposed to be output into final file needs to be
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explicitly marked by frontend via VARPOOL_FINALIZE_DECL function. */
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explicitly marked by frontend via VARPOOL_FINALIZE_DECL function. */
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|
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/* Hash table used to convert declarations into nodes. */
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/* Hash table used to convert declarations into nodes. */
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static GTY((param_is (struct varpool_node))) htab_t varpool_hash;
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static GTY((param_is (struct varpool_node))) htab_t varpool_hash;
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|
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/* The linked list of cgraph varpool nodes.
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/* The linked list of cgraph varpool nodes.
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Linked via node->next pointer. */
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Linked via node->next pointer. */
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struct varpool_node *varpool_nodes;
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struct varpool_node *varpool_nodes;
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|
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/* Queue of cgraph nodes scheduled to be lowered and output.
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/* Queue of cgraph nodes scheduled to be lowered and output.
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The queue is maintained via mark_needed_node, linked via node->next_needed
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The queue is maintained via mark_needed_node, linked via node->next_needed
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pointer.
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pointer.
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|
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LAST_NEEDED_NODE points to the end of queue, so it can be
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LAST_NEEDED_NODE points to the end of queue, so it can be
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maintained in forward order. GTY is needed to make it friendly to
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maintained in forward order. GTY is needed to make it friendly to
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PCH.
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PCH.
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|
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During compilation we construct the queue of needed variables
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During compilation we construct the queue of needed variables
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twice: first time it is during cgraph construction, second time it is at the
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twice: first time it is during cgraph construction, second time it is at the
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end of compilation in VARPOOL_REMOVE_UNREFERENCED_DECLS so we can avoid
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end of compilation in VARPOOL_REMOVE_UNREFERENCED_DECLS so we can avoid
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optimized out variables being output.
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optimized out variables being output.
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|
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Each variable is thus first analyzed and then later possibly output.
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Each variable is thus first analyzed and then later possibly output.
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FIRST_UNANALYZED_NODE points to first node in queue that was not analyzed
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FIRST_UNANALYZED_NODE points to first node in queue that was not analyzed
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yet and is moved via VARPOOL_ANALYZE_PENDING_DECLS. */
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yet and is moved via VARPOOL_ANALYZE_PENDING_DECLS. */
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|
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struct varpool_node *varpool_nodes_queue;
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struct varpool_node *varpool_nodes_queue;
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static GTY(()) struct varpool_node *varpool_last_needed_node;
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static GTY(()) struct varpool_node *varpool_last_needed_node;
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static GTY(()) struct varpool_node *varpool_first_unanalyzed_node;
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static GTY(()) struct varpool_node *varpool_first_unanalyzed_node;
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|
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/* Lists all assembled variables to be sent to debugger output later on. */
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/* Lists all assembled variables to be sent to debugger output later on. */
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static GTY(()) struct varpool_node *varpool_assembled_nodes_queue;
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static GTY(()) struct varpool_node *varpool_assembled_nodes_queue;
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|
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/* Return name of the node used in debug output. */
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/* Return name of the node used in debug output. */
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const char *
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const char *
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varpool_node_name (struct varpool_node *node)
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varpool_node_name (struct varpool_node *node)
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{
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{
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return lang_hooks.decl_printable_name (node->decl, 2);
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return lang_hooks.decl_printable_name (node->decl, 2);
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}
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}
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|
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/* Returns a hash code for P. */
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/* Returns a hash code for P. */
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static hashval_t
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static hashval_t
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hash_varpool_node (const void *p)
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hash_varpool_node (const void *p)
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{
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{
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const struct varpool_node *n = (const struct varpool_node *) p;
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const struct varpool_node *n = (const struct varpool_node *) p;
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return (hashval_t) DECL_UID (n->decl);
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return (hashval_t) DECL_UID (n->decl);
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}
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}
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|
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/* Returns nonzero if P1 and P2 are equal. */
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/* Returns nonzero if P1 and P2 are equal. */
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static int
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static int
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eq_varpool_node (const void *p1, const void *p2)
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eq_varpool_node (const void *p1, const void *p2)
|
{
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{
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const struct varpool_node *n1 =
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const struct varpool_node *n1 =
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(const struct varpool_node *) p1;
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(const struct varpool_node *) p1;
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const struct varpool_node *n2 =
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const struct varpool_node *n2 =
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(const struct varpool_node *) p2;
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(const struct varpool_node *) p2;
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return DECL_UID (n1->decl) == DECL_UID (n2->decl);
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return DECL_UID (n1->decl) == DECL_UID (n2->decl);
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}
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}
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/* Return varpool node assigned to DECL. Create new one when needed. */
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/* Return varpool node assigned to DECL. Create new one when needed. */
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struct varpool_node *
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struct varpool_node *
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varpool_node (tree decl)
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varpool_node (tree decl)
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{
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{
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struct varpool_node key, *node, **slot;
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struct varpool_node key, *node, **slot;
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|
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gcc_assert (DECL_P (decl) && TREE_CODE (decl) != FUNCTION_DECL);
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gcc_assert (DECL_P (decl) && TREE_CODE (decl) != FUNCTION_DECL);
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if (!varpool_hash)
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if (!varpool_hash)
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varpool_hash = htab_create_ggc (10, hash_varpool_node,
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varpool_hash = htab_create_ggc (10, hash_varpool_node,
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eq_varpool_node, NULL);
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eq_varpool_node, NULL);
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key.decl = decl;
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key.decl = decl;
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slot = (struct varpool_node **)
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slot = (struct varpool_node **)
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htab_find_slot (varpool_hash, &key, INSERT);
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htab_find_slot (varpool_hash, &key, INSERT);
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if (*slot)
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if (*slot)
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return *slot;
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return *slot;
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node = GGC_CNEW (struct varpool_node);
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node = GGC_CNEW (struct varpool_node);
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node->decl = decl;
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node->decl = decl;
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node->order = cgraph_order++;
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node->order = cgraph_order++;
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node->next = varpool_nodes;
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node->next = varpool_nodes;
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varpool_nodes = node;
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varpool_nodes = node;
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*slot = node;
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*slot = node;
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return node;
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return node;
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}
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}
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/* Dump given cgraph node. */
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/* Dump given cgraph node. */
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void
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void
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dump_varpool_node (FILE *f, struct varpool_node *node)
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dump_varpool_node (FILE *f, struct varpool_node *node)
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{
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{
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fprintf (f, "%s:", varpool_node_name (node));
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fprintf (f, "%s:", varpool_node_name (node));
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fprintf (f, " availability:%s",
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fprintf (f, " availability:%s",
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cgraph_function_flags_ready
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cgraph_function_flags_ready
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? cgraph_availability_names[cgraph_variable_initializer_availability (node)]
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? cgraph_availability_names[cgraph_variable_initializer_availability (node)]
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: "not-ready");
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: "not-ready");
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if (DECL_INITIAL (node->decl))
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if (DECL_INITIAL (node->decl))
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fprintf (f, " initialized");
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fprintf (f, " initialized");
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if (node->needed)
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if (node->needed)
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fprintf (f, " needed");
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fprintf (f, " needed");
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if (node->analyzed)
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if (node->analyzed)
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fprintf (f, " analyzed");
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fprintf (f, " analyzed");
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if (node->finalized)
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if (node->finalized)
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fprintf (f, " finalized");
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fprintf (f, " finalized");
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if (node->output)
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if (node->output)
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fprintf (f, " output");
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fprintf (f, " output");
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if (node->externally_visible)
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if (node->externally_visible)
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fprintf (f, " externally_visible");
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fprintf (f, " externally_visible");
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fprintf (f, "\n");
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fprintf (f, "\n");
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}
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}
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/* Dump the variable pool. */
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/* Dump the variable pool. */
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void
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void
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dump_varpool (FILE *f)
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dump_varpool (FILE *f)
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{
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{
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struct varpool_node *node;
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struct varpool_node *node;
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fprintf (f, "variable pool:\n\n");
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fprintf (f, "variable pool:\n\n");
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for (node = varpool_nodes; node; node = node->next)
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for (node = varpool_nodes; node; node = node->next)
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dump_varpool_node (f, node);
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dump_varpool_node (f, node);
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}
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}
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/* Dump the variable pool to stderr. */
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/* Dump the variable pool to stderr. */
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void
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void
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debug_varpool (void)
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debug_varpool (void)
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{
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{
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dump_varpool (stderr);
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dump_varpool (stderr);
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}
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}
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/* Given an assembler name, lookup node. */
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/* Given an assembler name, lookup node. */
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struct varpool_node *
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struct varpool_node *
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varpool_node_for_asm (tree asmname)
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varpool_node_for_asm (tree asmname)
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{
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{
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struct varpool_node *node;
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struct varpool_node *node;
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|
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for (node = varpool_nodes; node ; node = node->next)
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for (node = varpool_nodes; node ; node = node->next)
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if (decl_assembler_name_equal (node->decl, asmname))
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if (decl_assembler_name_equal (node->decl, asmname))
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return node;
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return node;
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return NULL;
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return NULL;
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}
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}
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/* Helper function for finalization code - add node into lists so it will
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/* Helper function for finalization code - add node into lists so it will
|
be analyzed and compiled. */
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be analyzed and compiled. */
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static void
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static void
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varpool_enqueue_needed_node (struct varpool_node *node)
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varpool_enqueue_needed_node (struct varpool_node *node)
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{
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{
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if (varpool_last_needed_node)
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if (varpool_last_needed_node)
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varpool_last_needed_node->next_needed = node;
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varpool_last_needed_node->next_needed = node;
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varpool_last_needed_node = node;
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varpool_last_needed_node = node;
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node->next_needed = NULL;
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node->next_needed = NULL;
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if (!varpool_nodes_queue)
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if (!varpool_nodes_queue)
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varpool_nodes_queue = node;
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varpool_nodes_queue = node;
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if (!varpool_first_unanalyzed_node)
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if (!varpool_first_unanalyzed_node)
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varpool_first_unanalyzed_node = node;
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varpool_first_unanalyzed_node = node;
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notice_global_symbol (node->decl);
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notice_global_symbol (node->decl);
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}
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}
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/* Notify finalize_compilation_unit that given node is reachable
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/* Notify finalize_compilation_unit that given node is reachable
|
or needed. */
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or needed. */
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void
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void
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varpool_mark_needed_node (struct varpool_node *node)
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varpool_mark_needed_node (struct varpool_node *node)
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{
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{
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if (node->alias && node->extra_name)
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if (node->alias && node->extra_name)
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node = node->extra_name;
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node = node->extra_name;
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if (!node->needed && node->finalized
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if (!node->needed && node->finalized
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&& !TREE_ASM_WRITTEN (node->decl))
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&& !TREE_ASM_WRITTEN (node->decl))
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varpool_enqueue_needed_node (node);
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varpool_enqueue_needed_node (node);
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node->needed = 1;
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node->needed = 1;
|
}
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}
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|
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/* Reset the queue of needed nodes. */
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/* Reset the queue of needed nodes. */
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static void
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static void
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varpool_reset_queue (void)
|
varpool_reset_queue (void)
|
{
|
{
|
varpool_last_needed_node = NULL;
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varpool_last_needed_node = NULL;
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varpool_nodes_queue = NULL;
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varpool_nodes_queue = NULL;
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varpool_first_unanalyzed_node = NULL;
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varpool_first_unanalyzed_node = NULL;
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}
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}
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|
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/* Determine if variable DECL is needed. That is, visible to something
|
/* Determine if variable DECL is needed. That is, visible to something
|
either outside this translation unit, something magic in the system
|
either outside this translation unit, something magic in the system
|
configury */
|
configury */
|
bool
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bool
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decide_is_variable_needed (struct varpool_node *node, tree decl)
|
decide_is_variable_needed (struct varpool_node *node, tree decl)
|
{
|
{
|
/* If the user told us it is used, then it must be so. */
|
/* If the user told us it is used, then it must be so. */
|
if ((node->externally_visible && !DECL_COMDAT (decl))
|
if ((node->externally_visible && !DECL_COMDAT (decl))
|
|| node->force_output)
|
|| node->force_output)
|
return true;
|
return true;
|
|
|
/* ??? If the assembler name is set by hand, it is possible to assemble
|
/* ??? If the assembler name is set by hand, it is possible to assemble
|
the name later after finalizing the function and the fact is noticed
|
the name later after finalizing the function and the fact is noticed
|
in assemble_name then. This is arguably a bug. */
|
in assemble_name then. This is arguably a bug. */
|
if (DECL_ASSEMBLER_NAME_SET_P (decl)
|
if (DECL_ASSEMBLER_NAME_SET_P (decl)
|
&& TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
|
&& TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
|
return true;
|
return true;
|
|
|
/* Externally visible variables must be output. The exception is
|
/* Externally visible variables must be output. The exception is
|
COMDAT variables that must be output only when they are needed. */
|
COMDAT variables that must be output only when they are needed. */
|
if (TREE_PUBLIC (decl)
|
if (TREE_PUBLIC (decl)
|
&& !flag_whole_program
|
&& !flag_whole_program
|
&& !flag_lto
|
&& !flag_lto
|
&& !flag_whopr
|
&& !flag_whopr
|
&& !DECL_COMDAT (decl)
|
&& !DECL_COMDAT (decl)
|
&& !DECL_EXTERNAL (decl))
|
&& !DECL_EXTERNAL (decl))
|
return true;
|
return true;
|
|
|
/* When emulating tls, we actually see references to the control
|
/* When emulating tls, we actually see references to the control
|
variable, rather than the user-level variable. */
|
variable, rather than the user-level variable. */
|
if (!targetm.have_tls
|
if (!targetm.have_tls
|
&& TREE_CODE (decl) == VAR_DECL
|
&& TREE_CODE (decl) == VAR_DECL
|
&& DECL_THREAD_LOCAL_P (decl))
|
&& DECL_THREAD_LOCAL_P (decl))
|
{
|
{
|
tree control = emutls_decl (decl);
|
tree control = emutls_decl (decl);
|
if (decide_is_variable_needed (varpool_node (control), control))
|
if (decide_is_variable_needed (varpool_node (control), control))
|
return true;
|
return true;
|
}
|
}
|
|
|
/* When not reordering top level variables, we have to assume that
|
/* When not reordering top level variables, we have to assume that
|
we are going to keep everything. */
|
we are going to keep everything. */
|
if (flag_toplevel_reorder)
|
if (flag_toplevel_reorder)
|
return false;
|
return false;
|
|
|
/* We want to emit COMDAT variables only when absolutely necessary. */
|
/* We want to emit COMDAT variables only when absolutely necessary. */
|
if (DECL_COMDAT (decl))
|
if (DECL_COMDAT (decl))
|
return false;
|
return false;
|
return true;
|
return true;
|
}
|
}
|
|
|
/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
|
/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
|
middle end to output the variable to asm file, if needed or externally
|
middle end to output the variable to asm file, if needed or externally
|
visible. */
|
visible. */
|
void
|
void
|
varpool_finalize_decl (tree decl)
|
varpool_finalize_decl (tree decl)
|
{
|
{
|
struct varpool_node *node = varpool_node (decl);
|
struct varpool_node *node = varpool_node (decl);
|
|
|
/* FIXME: We don't really stream varpool datastructure and instead rebuild it
|
/* FIXME: We don't really stream varpool datastructure and instead rebuild it
|
by varpool_finalize_decl. This is not quite correct since this way we can't
|
by varpool_finalize_decl. This is not quite correct since this way we can't
|
attach any info to varpool. Eventually we will want to stream varpool nodes
|
attach any info to varpool. Eventually we will want to stream varpool nodes
|
and the flags.
|
and the flags.
|
|
|
For the moment just prevent analysis of varpool nodes to happen again, so
|
For the moment just prevent analysis of varpool nodes to happen again, so
|
we will re-try to compute "address_taken" flag of varpool that breaks
|
we will re-try to compute "address_taken" flag of varpool that breaks
|
in presence of clones. */
|
in presence of clones. */
|
if (in_lto_p)
|
if (in_lto_p)
|
node->analyzed = true;
|
node->analyzed = true;
|
|
|
/* The first declaration of a variable that comes through this function
|
/* The first declaration of a variable that comes through this function
|
decides whether it is global (in C, has external linkage)
|
decides whether it is global (in C, has external linkage)
|
or local (in C, has internal linkage). So do nothing more
|
or local (in C, has internal linkage). So do nothing more
|
if this function has already run. */
|
if this function has already run. */
|
if (node->finalized)
|
if (node->finalized)
|
{
|
{
|
if (cgraph_global_info_ready)
|
if (cgraph_global_info_ready)
|
varpool_assemble_pending_decls ();
|
varpool_assemble_pending_decls ();
|
return;
|
return;
|
}
|
}
|
if (node->needed)
|
if (node->needed)
|
varpool_enqueue_needed_node (node);
|
varpool_enqueue_needed_node (node);
|
node->finalized = true;
|
node->finalized = true;
|
|
|
if (decide_is_variable_needed (node, decl))
|
if (decide_is_variable_needed (node, decl))
|
varpool_mark_needed_node (node);
|
varpool_mark_needed_node (node);
|
/* Since we reclaim unreachable nodes at the end of every language
|
/* Since we reclaim unreachable nodes at the end of every language
|
level unit, we need to be conservative about possible entry points
|
level unit, we need to be conservative about possible entry points
|
there. */
|
there. */
|
else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
|
else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
|
varpool_mark_needed_node (node);
|
varpool_mark_needed_node (node);
|
if (cgraph_global_info_ready)
|
if (cgraph_global_info_ready)
|
varpool_assemble_pending_decls ();
|
varpool_assemble_pending_decls ();
|
}
|
}
|
|
|
/* Return variable availability. See cgraph.h for description of individual
|
/* Return variable availability. See cgraph.h for description of individual
|
return values. */
|
return values. */
|
enum availability
|
enum availability
|
cgraph_variable_initializer_availability (struct varpool_node *node)
|
cgraph_variable_initializer_availability (struct varpool_node *node)
|
{
|
{
|
gcc_assert (cgraph_function_flags_ready);
|
gcc_assert (cgraph_function_flags_ready);
|
if (!node->finalized)
|
if (!node->finalized)
|
return AVAIL_NOT_AVAILABLE;
|
return AVAIL_NOT_AVAILABLE;
|
if (!TREE_PUBLIC (node->decl))
|
if (!TREE_PUBLIC (node->decl))
|
return AVAIL_AVAILABLE;
|
return AVAIL_AVAILABLE;
|
/* If the variable can be overwritten, return OVERWRITABLE. Takes
|
/* If the variable can be overwritten, return OVERWRITABLE. Takes
|
care of at least two notable extensions - the COMDAT variables
|
care of at least two notable extensions - the COMDAT variables
|
used to share template instantiations in C++. */
|
used to share template instantiations in C++. */
|
if (!(*targetm.binds_local_p) (node->decl) && !DECL_COMDAT (node->decl))
|
if (!(*targetm.binds_local_p) (node->decl) && !DECL_COMDAT (node->decl))
|
return AVAIL_OVERWRITABLE;
|
return AVAIL_OVERWRITABLE;
|
return AVAIL_AVAILABLE;
|
return AVAIL_AVAILABLE;
|
}
|
}
|
|
|
/* Walk the decls we marked as necessary and see if they reference new
|
/* Walk the decls we marked as necessary and see if they reference new
|
variables or functions and add them into the worklists. */
|
variables or functions and add them into the worklists. */
|
bool
|
bool
|
varpool_analyze_pending_decls (void)
|
varpool_analyze_pending_decls (void)
|
{
|
{
|
bool changed = false;
|
bool changed = false;
|
timevar_push (TV_CGRAPH);
|
timevar_push (TV_CGRAPH);
|
|
|
while (varpool_first_unanalyzed_node)
|
while (varpool_first_unanalyzed_node)
|
{
|
{
|
tree decl = varpool_first_unanalyzed_node->decl;
|
tree decl = varpool_first_unanalyzed_node->decl;
|
bool analyzed = varpool_first_unanalyzed_node->analyzed;
|
bool analyzed = varpool_first_unanalyzed_node->analyzed;
|
|
|
varpool_first_unanalyzed_node->analyzed = true;
|
varpool_first_unanalyzed_node->analyzed = true;
|
|
|
varpool_first_unanalyzed_node = varpool_first_unanalyzed_node->next_needed;
|
varpool_first_unanalyzed_node = varpool_first_unanalyzed_node->next_needed;
|
|
|
/* When reading back varpool at LTO time, we re-construct the queue in order
|
/* When reading back varpool at LTO time, we re-construct the queue in order
|
to have "needed" list right by inserting all needed nodes into varpool.
|
to have "needed" list right by inserting all needed nodes into varpool.
|
We however don't want to re-analyze already analyzed nodes. */
|
We however don't want to re-analyze already analyzed nodes. */
|
if (!analyzed)
|
if (!analyzed)
|
{
|
{
|
gcc_assert (!in_lto_p);
|
gcc_assert (!in_lto_p);
|
/* Compute the alignment early so function body expanders are
|
/* Compute the alignment early so function body expanders are
|
already informed about increased alignment. */
|
already informed about increased alignment. */
|
align_variable (decl, 0);
|
align_variable (decl, 0);
|
}
|
}
|
if (DECL_INITIAL (decl))
|
if (DECL_INITIAL (decl))
|
record_references_in_initializer (decl, analyzed);
|
record_references_in_initializer (decl, analyzed);
|
changed = true;
|
changed = true;
|
}
|
}
|
timevar_pop (TV_CGRAPH);
|
timevar_pop (TV_CGRAPH);
|
return changed;
|
return changed;
|
}
|
}
|
|
|
/* Output one variable, if necessary. Return whether we output it. */
|
/* Output one variable, if necessary. Return whether we output it. */
|
bool
|
bool
|
varpool_assemble_decl (struct varpool_node *node)
|
varpool_assemble_decl (struct varpool_node *node)
|
{
|
{
|
tree decl = node->decl;
|
tree decl = node->decl;
|
|
|
if (!TREE_ASM_WRITTEN (decl)
|
if (!TREE_ASM_WRITTEN (decl)
|
&& !node->alias
|
&& !node->alias
|
&& !DECL_EXTERNAL (decl)
|
&& !DECL_EXTERNAL (decl)
|
&& (TREE_CODE (decl) != VAR_DECL || !DECL_HAS_VALUE_EXPR_P (decl)))
|
&& (TREE_CODE (decl) != VAR_DECL || !DECL_HAS_VALUE_EXPR_P (decl)))
|
{
|
{
|
assemble_variable (decl, 0, 1, 0);
|
assemble_variable (decl, 0, 1, 0);
|
if (TREE_ASM_WRITTEN (decl))
|
if (TREE_ASM_WRITTEN (decl))
|
{
|
{
|
struct varpool_node *alias;
|
struct varpool_node *alias;
|
|
|
node->next_needed = varpool_assembled_nodes_queue;
|
node->next_needed = varpool_assembled_nodes_queue;
|
varpool_assembled_nodes_queue = node;
|
varpool_assembled_nodes_queue = node;
|
node->finalized = 1;
|
node->finalized = 1;
|
|
|
/* Also emit any extra name aliases. */
|
/* Also emit any extra name aliases. */
|
for (alias = node->extra_name; alias; alias = alias->next)
|
for (alias = node->extra_name; alias; alias = alias->next)
|
{
|
{
|
/* Update linkage fields in case they've changed. */
|
/* Update linkage fields in case they've changed. */
|
DECL_WEAK (alias->decl) = DECL_WEAK (decl);
|
DECL_WEAK (alias->decl) = DECL_WEAK (decl);
|
TREE_PUBLIC (alias->decl) = TREE_PUBLIC (decl);
|
TREE_PUBLIC (alias->decl) = TREE_PUBLIC (decl);
|
DECL_VISIBILITY (alias->decl) = DECL_VISIBILITY (decl);
|
DECL_VISIBILITY (alias->decl) = DECL_VISIBILITY (decl);
|
assemble_alias (alias->decl, DECL_ASSEMBLER_NAME (decl));
|
assemble_alias (alias->decl, DECL_ASSEMBLER_NAME (decl));
|
}
|
}
|
|
|
return true;
|
return true;
|
}
|
}
|
}
|
}
|
|
|
return false;
|
return false;
|
}
|
}
|
|
|
/* Optimization of function bodies might've rendered some variables as
|
/* Optimization of function bodies might've rendered some variables as
|
unnecessary so we want to avoid these from being compiled.
|
unnecessary so we want to avoid these from being compiled.
|
|
|
This is done by pruning the queue and keeping only the variables that
|
This is done by pruning the queue and keeping only the variables that
|
really appear needed (ie they are either externally visible or referenced
|
really appear needed (ie they are either externally visible or referenced
|
by compiled function). Re-doing the reachability analysis on variables
|
by compiled function). Re-doing the reachability analysis on variables
|
brings back the remaining variables referenced by these. */
|
brings back the remaining variables referenced by these. */
|
void
|
void
|
varpool_remove_unreferenced_decls (void)
|
varpool_remove_unreferenced_decls (void)
|
{
|
{
|
struct varpool_node *next, *node = varpool_nodes_queue;
|
struct varpool_node *next, *node = varpool_nodes_queue;
|
|
|
varpool_reset_queue ();
|
varpool_reset_queue ();
|
|
|
if (errorcount || sorrycount)
|
if (errorcount || sorrycount)
|
return;
|
return;
|
|
|
while (node)
|
while (node)
|
{
|
{
|
tree decl = node->decl;
|
tree decl = node->decl;
|
next = node->next_needed;
|
next = node->next_needed;
|
node->needed = 0;
|
node->needed = 0;
|
|
|
if (node->finalized
|
if (node->finalized
|
&& (decide_is_variable_needed (node, decl)
|
&& (decide_is_variable_needed (node, decl)
|
/* ??? Cgraph does not yet rule the world with an iron hand,
|
/* ??? Cgraph does not yet rule the world with an iron hand,
|
and does not control the emission of debug information.
|
and does not control the emission of debug information.
|
After a variable has its DECL_RTL set, we must assume that
|
After a variable has its DECL_RTL set, we must assume that
|
it may be referenced by the debug information, and we can
|
it may be referenced by the debug information, and we can
|
no longer elide it. */
|
no longer elide it. */
|
|| DECL_RTL_SET_P (decl)))
|
|| DECL_RTL_SET_P (decl)))
|
varpool_mark_needed_node (node);
|
varpool_mark_needed_node (node);
|
|
|
node = next;
|
node = next;
|
}
|
}
|
/* Make sure we mark alias targets as used targets. */
|
/* Make sure we mark alias targets as used targets. */
|
finish_aliases_1 ();
|
finish_aliases_1 ();
|
varpool_analyze_pending_decls ();
|
varpool_analyze_pending_decls ();
|
}
|
}
|
|
|
/* Output all variables enqueued to be assembled. */
|
/* Output all variables enqueued to be assembled. */
|
bool
|
bool
|
varpool_assemble_pending_decls (void)
|
varpool_assemble_pending_decls (void)
|
{
|
{
|
bool changed = false;
|
bool changed = false;
|
|
|
if (errorcount || sorrycount)
|
if (errorcount || sorrycount)
|
return false;
|
return false;
|
|
|
/* EH might mark decls as needed during expansion. This should be safe since
|
/* EH might mark decls as needed during expansion. This should be safe since
|
we don't create references to new function, but it should not be used
|
we don't create references to new function, but it should not be used
|
elsewhere. */
|
elsewhere. */
|
varpool_analyze_pending_decls ();
|
varpool_analyze_pending_decls ();
|
|
|
while (varpool_nodes_queue)
|
while (varpool_nodes_queue)
|
{
|
{
|
struct varpool_node *node = varpool_nodes_queue;
|
struct varpool_node *node = varpool_nodes_queue;
|
|
|
varpool_nodes_queue = varpool_nodes_queue->next_needed;
|
varpool_nodes_queue = varpool_nodes_queue->next_needed;
|
if (varpool_assemble_decl (node))
|
if (varpool_assemble_decl (node))
|
changed = true;
|
changed = true;
|
else
|
else
|
node->next_needed = NULL;
|
node->next_needed = NULL;
|
}
|
}
|
/* varpool_nodes_queue is now empty, clear the pointer to the last element
|
/* varpool_nodes_queue is now empty, clear the pointer to the last element
|
in the queue. */
|
in the queue. */
|
varpool_last_needed_node = NULL;
|
varpool_last_needed_node = NULL;
|
return changed;
|
return changed;
|
}
|
}
|
|
|
/* Remove all elements from the queue so we can re-use it for debug output. */
|
/* Remove all elements from the queue so we can re-use it for debug output. */
|
void
|
void
|
varpool_empty_needed_queue (void)
|
varpool_empty_needed_queue (void)
|
{
|
{
|
/* EH might mark decls as needed during expansion. This should be safe since
|
/* EH might mark decls as needed during expansion. This should be safe since
|
we don't create references to new function, but it should not be used
|
we don't create references to new function, but it should not be used
|
elsewhere. */
|
elsewhere. */
|
varpool_analyze_pending_decls ();
|
varpool_analyze_pending_decls ();
|
|
|
while (varpool_nodes_queue)
|
while (varpool_nodes_queue)
|
{
|
{
|
struct varpool_node *node = varpool_nodes_queue;
|
struct varpool_node *node = varpool_nodes_queue;
|
varpool_nodes_queue = varpool_nodes_queue->next_needed;
|
varpool_nodes_queue = varpool_nodes_queue->next_needed;
|
node->next_needed = NULL;
|
node->next_needed = NULL;
|
}
|
}
|
/* varpool_nodes_queue is now empty, clear the pointer to the last element
|
/* varpool_nodes_queue is now empty, clear the pointer to the last element
|
in the queue. */
|
in the queue. */
|
varpool_last_needed_node = NULL;
|
varpool_last_needed_node = NULL;
|
}
|
}
|
|
|
/* Create a new global variable of type TYPE. */
|
/* Create a new global variable of type TYPE. */
|
tree
|
tree
|
add_new_static_var (tree type)
|
add_new_static_var (tree type)
|
{
|
{
|
tree new_decl;
|
tree new_decl;
|
struct varpool_node *new_node;
|
struct varpool_node *new_node;
|
|
|
new_decl = create_tmp_var (type, NULL);
|
new_decl = create_tmp_var (type, NULL);
|
DECL_NAME (new_decl) = create_tmp_var_name (NULL);
|
DECL_NAME (new_decl) = create_tmp_var_name (NULL);
|
TREE_READONLY (new_decl) = 0;
|
TREE_READONLY (new_decl) = 0;
|
TREE_STATIC (new_decl) = 1;
|
TREE_STATIC (new_decl) = 1;
|
TREE_USED (new_decl) = 1;
|
TREE_USED (new_decl) = 1;
|
DECL_CONTEXT (new_decl) = NULL_TREE;
|
DECL_CONTEXT (new_decl) = NULL_TREE;
|
DECL_ABSTRACT (new_decl) = 0;
|
DECL_ABSTRACT (new_decl) = 0;
|
lang_hooks.dup_lang_specific_decl (new_decl);
|
lang_hooks.dup_lang_specific_decl (new_decl);
|
create_var_ann (new_decl);
|
create_var_ann (new_decl);
|
new_node = varpool_node (new_decl);
|
new_node = varpool_node (new_decl);
|
varpool_mark_needed_node (new_node);
|
varpool_mark_needed_node (new_node);
|
add_referenced_var (new_decl);
|
add_referenced_var (new_decl);
|
varpool_finalize_decl (new_decl);
|
varpool_finalize_decl (new_decl);
|
|
|
return new_node->decl;
|
return new_node->decl;
|
}
|
}
|
|
|
/* Attempt to mark ALIAS as an alias to DECL. Return TRUE if successful.
|
/* Attempt to mark ALIAS as an alias to DECL. Return TRUE if successful.
|
Extra name aliases are output whenever DECL is output. */
|
Extra name aliases are output whenever DECL is output. */
|
|
|
bool
|
bool
|
varpool_extra_name_alias (tree alias, tree decl)
|
varpool_extra_name_alias (tree alias, tree decl)
|
{
|
{
|
struct varpool_node key, *alias_node, *decl_node, **slot;
|
struct varpool_node key, *alias_node, *decl_node, **slot;
|
|
|
#ifndef ASM_OUTPUT_DEF
|
#ifndef ASM_OUTPUT_DEF
|
/* If aliases aren't supported by the assembler, fail. */
|
/* If aliases aren't supported by the assembler, fail. */
|
return false;
|
return false;
|
#endif
|
#endif
|
|
|
gcc_assert (TREE_CODE (decl) == VAR_DECL);
|
gcc_assert (TREE_CODE (decl) == VAR_DECL);
|
gcc_assert (TREE_CODE (alias) == VAR_DECL);
|
gcc_assert (TREE_CODE (alias) == VAR_DECL);
|
/* Make sure the hash table has been created. */
|
/* Make sure the hash table has been created. */
|
decl_node = varpool_node (decl);
|
decl_node = varpool_node (decl);
|
|
|
key.decl = alias;
|
key.decl = alias;
|
|
|
slot = (struct varpool_node **) htab_find_slot (varpool_hash, &key, INSERT);
|
slot = (struct varpool_node **) htab_find_slot (varpool_hash, &key, INSERT);
|
|
|
/* If the varpool_node has been already created, fail. */
|
/* If the varpool_node has been already created, fail. */
|
if (*slot)
|
if (*slot)
|
return false;
|
return false;
|
|
|
alias_node = GGC_CNEW (struct varpool_node);
|
alias_node = GGC_CNEW (struct varpool_node);
|
alias_node->decl = alias;
|
alias_node->decl = alias;
|
alias_node->alias = 1;
|
alias_node->alias = 1;
|
alias_node->extra_name = decl_node;
|
alias_node->extra_name = decl_node;
|
alias_node->next = decl_node->extra_name;
|
alias_node->next = decl_node->extra_name;
|
decl_node->extra_name = alias_node;
|
decl_node->extra_name = alias_node;
|
*slot = alias_node;
|
*slot = alias_node;
|
return true;
|
return true;
|
}
|
}
|
|
|
#include "gt-varpool.h"
|
#include "gt-varpool.h"
|
|
|
