re PR middle-end/43513 (The stack pointer is adjusted twice)

2011-07-30  Tom de Vries  <tom@codesourcery.com>

	PR middle-end/43513
	* tree-ssa-dce.c (ref_may_be_aliased): Add assert.
	(propagate_necessity): Handle WITH_SIZE_EXPR call arg.

From-SVN: r176959

gcc/ChangeLog

+2011-07-30  Tom de Vries  <tom@codesourcery.com>
+
+	PR middle-end/43513
+	* tree-ssa-dce.c (ref_may_be_aliased): Add assert.
+	(propagate_necessity): Handle WITH_SIZE_EXPR call arg.
+
 2011-07-29  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* config/mips/driver-native.c [__sgi__]: Include <invent.h>,

gcc/tree-ssa-dce.c

@@ -490,6 +490,7 @@ find_obviously_necessary_stmts (struct edge_list *el)
 static bool
 ref_may_be_aliased (tree ref)
 {
+  gcc_assert (TREE_CODE (ref) != WITH_SIZE_EXPR);
   while (handled_component_p (ref))
     ref = TREE_OPERAND (ref, 0);
   if (TREE_CODE (ref) == MEM_REF
@@ -850,6 +851,8 @@ propagate_necessity (struct edge_list *el)
 		  if (TREE_CODE (arg) == SSA_NAME
 		      || is_gimple_min_invariant (arg))
 		    continue;
+		  if (TREE_CODE (arg) == WITH_SIZE_EXPR)
+		    arg = TREE_OPERAND (arg, 0);
 		  if (!ref_may_be_aliased (arg))
 		    mark_aliased_reaching_defs_necessary (stmt, arg);
 		}