2005-12-23 Daniel Berlin <dberlin@dberlin.org>

	* tree-pass.h (pass_eliminate_useless_stores): Remove.
	* tree-ssa-pre.c (is_copy_stmt): Ditto.
	(follow_copies_till_vuse): Ditto.
	(do_eustore): Ditto.
	(gate_eustores): Ditto.
	(pass_eliminate_useless_stores): Ditto.
	* passes.c (init_optimization_passes): Ditto.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@109034 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 0 insertions, 132 deletions

diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c
index 08964004d0a..1f469292622 100644
--- a/gcc/tree-ssa-pre.c
+++ b/gcc/tree-ssa-pre.c
@@ -2928,135 +2928,3 @@ struct tree_opt_pass pass_fre =
   0					/* letter */
 };
 
-/* Return true if T is a copy statement between two ssa names.  */
-
-static bool
-is_copy_stmt (tree t)
-{  
-  if (!t || TREE_CODE (t) != MODIFY_EXPR)
-    return false;
-  if (TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME 
-      && TREE_CODE (TREE_OPERAND (t, 1)) == SSA_NAME)
-    return true;
-  return false;
-}
-
-/* Starting from START, walk copy statements till we hit a statement with a
-   VUSE or a non-copy statement.  */
-
-static tree 
-follow_copies_till_vuse (tree start)
-{
-  if (is_copy_stmt (start) && ZERO_SSA_OPERANDS (start, SSA_OP_VIRTUAL_USES))
-    {
-      tree rhs, defstmt;
-
-      rhs = TREE_OPERAND (start, 1);
-      defstmt = SSA_NAME_DEF_STMT (rhs);
-      return follow_copies_till_vuse (defstmt);
-    }
-  return start;
-}
-
-/* Gate and execute functions for eliminate useless stores.	
-   The goal here is to recognize the pattern *x = ... *x, and eliminate the
-   store because the value hasn't changed.  Store copy/const prop won't
-   do this because making *more* loads (IE propagating *x) is not a win, so it
-   ignores them.  
-   This pass is currently geared completely towards static variable store
-   elimination.  */
-
-static void
-do_eustores (void)
-{
-  basic_block bb;
-  /* For each basic block
-       For each statement (STMT) in the block
-         if STMT is a stores of the pattern *x = y
-           follow the chain of definitions for y, until we hit a non-copy
-	   statement or a statement with a vuse. 
-	     if the statement we arrive at is a vuse of the operand we killed,
-	     accessed through the same memory operation, then we have a
-	     useless store (because it is *x = ... = *x).  */
-	  
-  FOR_EACH_BB (bb)
-    {
-      block_stmt_iterator bsi;
-
-      for (bsi = bsi_start (bb);
-	   !bsi_end_p (bsi);)
-	{
-	  tree stmt = bsi_stmt (bsi);
-	  tree startat;
-	  tree kill;	  
-	  tree found;
-	  	  
-	  if (NUM_SSA_OPERANDS (stmt, SSA_OP_VMUSTDEF) != 1
-	      || TREE_CODE (stmt) != MODIFY_EXPR
-	      || TREE_CODE (TREE_OPERAND (stmt, 1)) != SSA_NAME)
-	    {
-	      bsi_next (&bsi);
-	      continue;
-	    }
-
-	  kill = MUSTDEF_KILL (MUSTDEF_OPS (stmt)); 
-	  startat = TREE_OPERAND (stmt, 1);
-	  startat = SSA_NAME_DEF_STMT (startat);
-	  found = follow_copies_till_vuse (startat);
-
-	  if (found && TREE_CODE (found) == MODIFY_EXPR)
-	    {	   
-
-	      /* We want exactly one virtual use, and it should match up with
-		 the use being killed.  */
-
-	      if (NUM_SSA_OPERANDS (found, SSA_OP_VUSE) != 1
-		  || VUSE_OP (VUSE_OPS (found)) != kill
-		  || !DECL_P (TREE_OPERAND (stmt, 0))
-		  || !operand_equal_p (TREE_OPERAND (found, 1), 
-				       TREE_OPERAND (stmt, 0), 0))
-		{
-		  bsi_next (&bsi);
-		  continue;
-		}
-
-	      if (dump_file)
-		{
-		  fprintf (dump_file, "Eliminating useless store ");
-		  print_generic_stmt (dump_file, stmt, 0);
-		}
-	      mark_sym_for_renaming (TREE_OPERAND (stmt, 0));
-	      bsi_remove (&bsi);
-	    }
-	  else
-	    {
-	      bsi_next (&bsi);
-	      continue;
-	    }
-	}
-    }
-}
-
-static bool
-gate_eustores(void)
-{
-  return flag_unit_at_a_time != 0;
-}
-
-struct tree_opt_pass pass_eliminate_useless_stores =
-{
-  "eustores",				/* name */
-  gate_eustores,				/* gate */
-  do_eustores,				/* execute */
-  NULL,					/* sub */
-  NULL,					/* next */
-  0,					/* static_pass_number */
-  0,				/* tv_id */
-  PROP_cfg | PROP_ssa | PROP_alias,	/* properties_required */
-  0,					/* properties_provided */
-  0,					/* properties_destroyed */
-  0,					/* todo_flags_start */
-  TODO_update_ssa | TODO_dump_func 
-  | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */
-  0					/* letter */
-};