/* Generic routines for manipulating SSA_NAME expressions
- Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
-
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009
+ Free Software Foundation, Inc.
+
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 51 Franklin Street, Fifth Floor,
-Boston, MA 02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "varray.h"
#include "ggc.h"
#include "tree-flow.h"
+#include "tree-pass.h"
/* Rewriting a function into SSA form can create a huge number of SSA_NAMEs,
many of which may be thrown away shortly after their creation if jumps
unsigned int ssa_name_nodes_created;
#endif
-/* Initialize management of SSA_NAMEs. */
+/* Initialize management of SSA_NAMEs to default SIZE. If SIZE is
+ zero use default. */
void
-init_ssanames (void)
+init_ssanames (struct function *fn, int size)
{
- SSANAMES (cfun) = VEC_alloc (tree, gc, 50);
+ if (size < 50)
+ size = 50;
+
+ SSANAMES (fn) = VEC_alloc (tree, gc, size);
/* Version 0 is special, so reserve the first slot in the table. Though
currently unused, we may use version 0 in alias analysis as part of
We use VEC_quick_push here because we know that SSA_NAMES has at
least 50 elements reserved in it. */
- VEC_quick_push (tree, SSANAMES (cfun), NULL_TREE);
- FREE_SSANAMES (cfun) = NULL;
+ VEC_quick_push (tree, SSANAMES (fn), NULL_TREE);
+ FREE_SSANAMES (fn) = NULL;
+
+ SYMS_TO_RENAME (fn) = BITMAP_GGC_ALLOC ();
}
/* Finalize management of SSA_NAMEs. */
}
#endif
-/* Return an SSA_NAME node for variable VAR defined in statement STMT.
- STMT may be an empty statement for artificial references (e.g., default
- definitions created when a variable is used without a preceding
- definition). */
+/* Return an SSA_NAME node for variable VAR defined in statement STMT
+ in function FN. STMT may be an empty statement for artificial
+ references (e.g., default definitions created when a variable is
+ used without a preceding definition). */
tree
-make_ssa_name (tree var, tree stmt)
+make_ssa_name_fn (struct function *fn, tree var, gimple stmt)
{
tree t;
use_operand_p imm;
- gcc_assert (DECL_P (var)
- || TREE_CODE (var) == INDIRECT_REF);
-
- gcc_assert (!stmt
- || EXPR_P (stmt) || GIMPLE_STMT_P (stmt)
- || TREE_CODE (stmt) == PHI_NODE);
+ gcc_assert (DECL_P (var));
/* If our free list has an element, then use it. */
- if (FREE_SSANAMES (cfun))
+ if (FREE_SSANAMES (fn))
{
- t = FREE_SSANAMES (cfun);
- FREE_SSANAMES (cfun) = TREE_CHAIN (FREE_SSANAMES (cfun));
+ t = FREE_SSANAMES (fn);
+ FREE_SSANAMES (fn) = TREE_CHAIN (FREE_SSANAMES (fn));
#ifdef GATHER_STATISTICS
ssa_name_nodes_reused++;
#endif
/* The node was cleared out when we put it on the free list, so
there is no need to do so again here. */
gcc_assert (ssa_name (SSA_NAME_VERSION (t)) == NULL);
- VEC_replace (tree, SSANAMES (cfun), SSA_NAME_VERSION (t), t);
+ VEC_replace (tree, SSANAMES (fn), SSA_NAME_VERSION (t), t);
}
else
{
t = make_node (SSA_NAME);
- SSA_NAME_VERSION (t) = num_ssa_names;
- VEC_safe_push (tree, gc, SSANAMES (cfun), t);
+ SSA_NAME_VERSION (t) = VEC_length (tree, SSANAMES (fn));
+ VEC_safe_push (tree, gc, SSANAMES (fn), t);
#ifdef GATHER_STATISTICS
ssa_name_nodes_created++;
#endif
SSA_NAME_DEF_STMT (t) = stmt;
SSA_NAME_PTR_INFO (t) = NULL;
SSA_NAME_IN_FREE_LIST (t) = 0;
+ SSA_NAME_IS_DEFAULT_DEF (t) = 0;
imm = &(SSA_NAME_IMM_USE_NODE (t));
imm->use = NULL;
imm->prev = imm;
imm->next = imm;
- imm->stmt = t;
+ imm->loc.ssa_name = t;
return t;
}
/* Never release the default definition for a symbol. It's a
special SSA name that should always exist once it's created. */
- if (var == gimple_default_def (cfun, SSA_NAME_VAR (var)))
+ if (SSA_NAME_IS_DEFAULT_DEF (var))
return;
/* If VAR has been registered for SSA updating, don't remove it.
int saved_ssa_name_version = SSA_NAME_VERSION (var);
use_operand_p imm = &(SSA_NAME_IMM_USE_NODE (var));
+ if (MAY_HAVE_DEBUG_STMTS)
+ propagate_var_def_into_debug_stmts (var, NULL, NULL);
+
#ifdef ENABLE_CHECKING
verify_imm_links (stderr, var);
#endif
imm->prev = imm;
imm->next = imm;
- imm->stmt = var;
+ imm->loc.ssa_name = var;
+
/* First put back the right tree node so that the tree checking
macros do not complain. */
TREE_SET_CODE (var, SSA_NAME);
/* Creates a duplicate of a ssa name NAME defined in statement STMT. */
tree
-duplicate_ssa_name (tree name, tree stmt)
+duplicate_ssa_name (tree name, gimple stmt)
{
tree new_name = make_ssa_name (SSA_NAME_VAR (name), stmt);
struct ptr_info_def *old_ptr_info = SSA_NAME_PTR_INFO (name);
if (!ptr_info)
return;
- new_ptr_info = ggc_alloc (sizeof (struct ptr_info_def));
+ new_ptr_info = GGC_NEW (struct ptr_info_def);
*new_ptr_info = *ptr_info;
- if (ptr_info->pt_vars)
- {
- new_ptr_info->pt_vars = BITMAP_GGC_ALLOC ();
- bitmap_copy (new_ptr_info->pt_vars, ptr_info->pt_vars);
- }
-
SSA_NAME_PTR_INFO (name) = new_ptr_info;
}
/* Release all the SSA_NAMEs created by STMT. */
void
-release_defs (tree stmt)
+release_defs (gimple stmt)
{
tree def;
ssa_op_iter iter;
SSA_NAME_VAR (ssa_name) = sym;
TREE_TYPE (ssa_name) = TREE_TYPE (sym);
}
+
+/* Return SSA names that are unused to GGC memory. This is used to keep
+ footprint of compiler during interprocedural optimization.
+ As a side effect the SSA_NAME_VERSION number reuse is reduced
+ so this function should not be used too often. */
+static unsigned int
+release_dead_ssa_names (void)
+{
+ tree t, next;
+ int n = 0;
+ referenced_var_iterator rvi;
+
+ /* Current defs point to various dead SSA names that in turn points to dead
+ statements so bunch of dead memory is held from releasing. */
+ FOR_EACH_REFERENCED_VAR (t, rvi)
+ set_current_def (t, NULL);
+ /* Now release the freelist. */
+ for (t = FREE_SSANAMES (cfun); t; t = next)
+ {
+ next = TREE_CHAIN (t);
+ /* Dangling pointers might make GGC to still see dead SSA names, so it is
+ important to unlink the list and avoid GGC from seeing all subsequent
+ SSA names. In longer run we want to have all dangling pointers here
+ removed (since they usually go through dead statements that consume
+ considerable amounts of memory). */
+ TREE_CHAIN (t) = NULL_TREE;
+ n++;
+ }
+ FREE_SSANAMES (cfun) = NULL;
+
+ /* Cgraph edges has been invalidated and point to dead statement. We need to
+ remove them now and will rebuild it before next IPA pass. */
+ cgraph_node_remove_callees (cgraph_node (current_function_decl));
+
+ if (dump_file)
+ fprintf (dump_file, "Released %i names, %.2f%%\n", n, n * 100.0 / num_ssa_names);
+ return 0;
+}
+
+struct gimple_opt_pass pass_release_ssa_names =
+{
+ {
+ GIMPLE_PASS,
+ "release_ssa", /* name */
+ NULL, /* gate */
+ release_dead_ssa_names, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_NONE, /* tv_id */
+ PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func /* todo_flags_finish */
+ }
+};