Check zero/sign extended hard registers.

gcc/

2011-03-17  H.J. Lu  <hongjiu.lu@intel.com>

	PR middle-end/47725
	* combine.c (cant_combine_insn_p): Check zero/sign extended
	hard registers.

gcc/testsuite/

2011-03-17  H.J. Lu  <hongjiu.lu@intel.com>

	PR middle-end/47725
	* gcc.dg/torture/pr47725.c: New.

From-SVN: r171124

gcc/ChangeLog

+2011-03-17  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR middle-end/47725
+	* combine.c (cant_combine_insn_p): Check zero/sign extended
+	hard registers.
+
 2011-03-17  Anatoly Sokolov  <aesok@post.ru>
 
 	* config/v850/v850.h (OUTPUT_ADDR_CONST_EXTRA): Remove.

gcc/combine.c

@@ -2137,6 +2137,12 @@ cant_combine_insn_p (rtx insn)
     return 0;
   src = SET_SRC (set);
   dest = SET_DEST (set);
+  if (GET_CODE (src) == ZERO_EXTEND
+      || GET_CODE (src) == SIGN_EXTEND)
+    src = XEXP (src, 0);
+  if (GET_CODE (dest) == ZERO_EXTEND
+      || GET_CODE (dest) == SIGN_EXTEND)
+    dest = XEXP (dest, 0);
   if (GET_CODE (src) == SUBREG)
     src = SUBREG_REG (src);
   if (GET_CODE (dest) == SUBREG)

gcc/testsuite/ChangeLog

+2011-03-17  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR middle-end/47725
+	* gcc.dg/torture/pr47725.c: New.
+
 2011-03-17  Jason Merrill  <jason@redhat.com>
 
 	* g++.dg/cpp0x/constexpr-overflow2.C: New.

gcc/testsuite/gcc.dg/torture/pr47725.c

+/* { dg-do compile } */
+
+struct _Unwind_Context
+{
+  void *reg[17];
+  void *ra;
+};
+extern void bar (struct _Unwind_Context *);
+void
+__frame_state_for (void *pc_target)
+{
+  struct _Unwind_Context context;
+  __builtin_memset (&context, 0, sizeof (struct _Unwind_Context));
+  context.ra = pc_target;
+  bar (&context);
+}