diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 455fdcffb6b..30b07fabb4d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2011-06-20  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR middle-end/47725
+	* combine.c (cant_combine_insn_p): Don't check zero/sign
+	extended hard registers.
+
 2011-06-21  Alan Modra  <amodra@gmail.com>
 
 	* config/rs6000/rs6000.c (rs6000_cannot_force_const_mem): Match
diff --git a/gcc/combine.c b/gcc/combine.c
index 004ae27687d..56fb44eaf42 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -2168,12 +2168,6 @@ 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)