re PR rtl-optimization/42952 (possible integer wrong code bug)

2010-02-04  Richard Guenther  <rguenther@suse.de>

	PR rtl-optimization/42952
	* dse.c (const_or_frame_p): Remove MEM handling.

	* gcc.dg/torture/pr42952.c: New testcase.

From-SVN: r156494

gcc/ChangeLog

+2010-02-04  Richard Guenther  <rguenther@suse.de>
+
+	PR rtl-optimization/42952
+	* dse.c (const_or_frame_p): Remove MEM handling.
+
 2010-02-04  Nick Clifton  <nickc@redhat.com>
 
 	* config/mn10300/mn10300.c (TARGET_ASM_OUTPUT_MI_THUNK): Define.

gcc/dse.c

@@ -1015,9 +1015,6 @@ const_or_frame_p (rtx x)
 {
   switch (GET_CODE (x))
     {
-    case MEM:
-      return MEM_READONLY_P (x);
-
     case CONST:
     case CONST_INT:
     case CONST_DOUBLE:

gcc/testsuite/ChangeLog

+2010-02-04  Richard Guenther  <rguenther@suse.de>
+
+	PR rtl-optimization/42952
+	* gcc.dg/torture/pr42952.c: New testcase.
+
 2010-02-03  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
 
 	PR libfortran/42901

gcc/testsuite/gcc.dg/torture/pr42952.c

+/* { dg-do run } */
+/* { dg-options "-fno-tree-ccp -fno-tree-fre" } */
+
+extern void abort (void);
+
+static int g[1];
+
+static int * const p = &g[0];
+static int * const q = &g[0];
+
+int main(void)
+{
+  g[0] = 1;
+  *p = 0;
+  *p = *q;
+  if (g[0] != 0)
+    abort ();
+  return 0;
+}