* tree-into-ssa.c (set_livein_block): Fix typo in comment.

	(rewrite_ssa_into_ssa): Start iterating over SSA names at 1.
	Release SSA names that have been re-renamed.
	* tree-phinodes.c (make_phi_node): Set same TREE_TYPE as the
	variable.
	* tree-ssa-alias.c (init_alias_info): If aliases have been
	computed before, clear existing alias information.
	(create_name_tags): Do no fixup PT_ANYTHING pointers.
	If the new name tag for a pointer is different than the one it
	had before, mark the old tag for renaming.
	(replace_may_alias): New function.
	(group_aliases): Call it.
	(setup_pointers_and_addressables): Always call get_tmt_for.
	(maybe_create_global_var): Don't create .GLOBAL_VAR more than
	once.
	(set_pt_anything): New local function.
	(set_pt_malloc): New local function.
	(merge_pointed_to_info): Don't merge pointed-to variables from
	the original pointer if the destination is pointing to an
	unknown location.
	(add_pointed_to_expr): Call set_pt_anything and set_pt_malloc.
	(add_pointed_to_var): Do not add a variable to the points-to
	set if the pointer is already pointing to anywhere.
	(collect_points_to_info_r): If the defining statement is a PHI
	node, only merge pointed-to information if the argument has
	already been visited.
	(get_tmt_for): Only create a new tag if the pointer didn't
	have one already.
	(dump_alias_info): Emit more information.
	(dump_points_to_info_for): Likewise.
	* tree-ssa-dom.c (redirect_edges_and_update_ssa_graph): Don't
	try to get the annotation of an SSA_NAME.
	* tree-ssa-operands.c (add_stmt_operand): Only check for empty
	alias sets when checking is enabled.
	* tree-ssa-pre.c (need_eh_cleanup): New local variable.
	(eliminate): Mark basic blocks that will need
	EH information cleaned up.
	(init_pre): Split ENTRY_BLOCK->0 if block 0 has more than one
	predecessor.
	Initialize need_eh_cleanup.
	(fini_pre): Call tree_purge_all_dead_eh_edges and
	cleanup_tree_cfg if needed.
	Free need_eh_cleanup.
	* tree-ssa.c (verify_ssa_name): New function.
	(verify_def): Call it.
	Re-arrange to avoid printing too many error messages.
	(verify_use): Likewise.
	(verify_phi_args): Likewise.
	(verify_flow_insensitive_alias_info): New function.
	(verify_flow_sensitive_alias_info): New function.
	(verify_alias_info): New function.
	(verify_ssa): Call verify_alias_info.
	Clear TREE_VISITED on all the SSA_NAMEs before scanning the
	program.
	Re-arrange to avoid printing too many error messages.
	* tree-ssanames.c (make_ssa_name): Clear
	SSA_NAME_IN_FREE_LIST.
	(release_ssa_name): Never release a default definition.
	(release_defs): New function.
	* tree.h: Declare it.
	* tree-ssa-dce.c (remove_dead_stmt): Call it.


	* tree-ssa.c (walk_use_def_chains_1): Add new argument IS_DFS.
	If true, do a depth-first search.  Do a breadht-first search,
	otherwise.
	(walk_use_def_chains): Add new argument IS_DFS.
	Update all users.
	* tree-flow.h (walk_use_def_chains): Update prototype.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@85052 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 33 insertions, 0 deletions

diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c
index d4982706676..2785e530b3c 100644
--- a/gcc/tree-ssanames.c
+++ b/gcc/tree-ssanames.c
@@ -160,6 +160,7 @@ make_ssa_name (tree var, tree stmt)
   SSA_NAME_VAR (t) = var;
   SSA_NAME_DEF_STMT (t) = stmt;
   SSA_NAME_PTR_INFO (t) = NULL;
+  SSA_NAME_IN_FREE_LIST (t) = 0;
 
   return t;
 }
@@ -176,6 +177,11 @@ make_ssa_name (tree var, tree stmt)
 void
 release_ssa_name (tree var)
 {
+  /* Never release the default definition for a symbol.  It's a
+     special SSA name that should always exist once it's created.  */
+  if (var == var_ann (SSA_NAME_VAR (var))->default_def)
+    return;
+
   /* release_ssa_name can be called multiple times on a single SSA_NAME.
      However, it should only end up on our free list one time.   We
      keep a status bit in the SSA_NAME node itself to indicate it has
@@ -216,4 +222,31 @@ duplicate_ssa_name (tree name, tree stmt)
   return new_name;
 }
 
+
+/* Release all the SSA_NAMEs created by STMT.  */
+
+void
+release_defs (tree stmt)
+{
+  size_t i;
+  v_may_def_optype v_may_defs;
+  v_must_def_optype v_must_defs;
+  def_optype defs;
+  stmt_ann_t ann;
+
+  ann = stmt_ann (stmt);
+  defs = DEF_OPS (ann);
+  v_may_defs = V_MAY_DEF_OPS (ann);
+  v_must_defs = V_MUST_DEF_OPS (ann);
+
+  for (i = 0; i < NUM_DEFS (defs); i++)
+    release_ssa_name (DEF_OP (defs, i));
+
+  for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
+    release_ssa_name (V_MAY_DEF_RESULT (v_may_defs, i));
+
+  for (i = 0; i < NUM_V_MUST_DEFS (v_must_defs); i++)
+    release_ssa_name (V_MUST_DEF_OP (v_must_defs, i));
+}
+
 #include "gt-tree-ssanames.h"