re PR tree-optimization/40496 (ICE in verify_stmts with -fprefetch-loop-arrays)

2009-07-10  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/40496
	* tree-ssa-loop-manip.c (tree_transform_and_unroll_loop): Create
	the PHI result with a compatible type.

	* g++.dg/opt/pr40496.C: New testcase.

From-SVN: r149469

gcc/ChangeLog

+2009-07-10  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/40496
+	* tree-ssa-loop-manip.c (tree_transform_and_unroll_loop): Create
+	the PHI result with a compatible type.
+
 2009-07-10  Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
 	PR 25509

gcc/testsuite/ChangeLog

+2009-07-10  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/40496
+	* g++.dg/opt/pr40496.C: New testcase.
+
 2009-07-10  Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
 	PR 25509

gcc/testsuite/g++.dg/opt/pr40496.C

+// { dg-do compile }
+// { dg-options "-O2 -fprefetch-loop-arrays -msse2" { target i?86-*-* x86_64-*-* } }
+
+struct DOMStringHandle
+{
+  unsigned int fLength;
+  int fRefCount;
+};
+static void *freeListPtr;
+void foo(DOMStringHandle *dsg)
+{
+  int i;
+  for (i = 1; i < 1023; i++)
+    {
+      *(void **) &dsg[i] = freeListPtr;
+      freeListPtr = &dsg[i];
+    }
+}

gcc/tree-ssa-loop-manip.c

@@ -990,10 +990,19 @@ tree_transform_and_unroll_loop (struct loop *loop, unsigned factor,
       /* Prefer using original variable as a base for the new ssa name.
 	 This is necessary for virtual ops, and useful in order to avoid
 	 losing debug info for real ops.  */
-      if (TREE_CODE (next) == SSA_NAME)
+      if (TREE_CODE (next) == SSA_NAME
+	  && useless_type_conversion_p (TREE_TYPE (next),
+					TREE_TYPE (init)))
 	var = SSA_NAME_VAR (next);
-      else if (TREE_CODE (init) == SSA_NAME)
+      else if (TREE_CODE (init) == SSA_NAME
+	       && useless_type_conversion_p (TREE_TYPE (init),
+					     TREE_TYPE (next)))
 	var = SSA_NAME_VAR (init);
+      else if (useless_type_conversion_p (TREE_TYPE (next), TREE_TYPE (init)))
+	{
+	  var = create_tmp_var (TREE_TYPE (next), "unrinittmp");
+	  add_referenced_var (var);
+	}
       else
 	{
 	  var = create_tmp_var (TREE_TYPE (init), "unrinittmp");