Don't propagate hard registers in forward_propagate_subreg.

2011-07-05  H.J. Lu  <hongjiu.lu@intel.com>

	PR rtl-optimization/47449
	* fwprop.c (forward_propagate_subreg): Don't propagate hard
	register nor zero/sign extended hard register.

From-SVN: r175849

gcc/ChangeLog

+2011-07-05  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR rtl-optimization/47449
+	* fwprop.c (forward_propagate_subreg): Don't propagate hard
+	register nor zero/sign extended hard register.
+
 2011-07-05  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/49518

gcc/fwprop.c

@@ -1101,6 +1101,7 @@ forward_propagate_subreg (df_ref use, rtx def_insn, rtx def_set)
       src = SET_SRC (def_set);
       if (GET_CODE (src) == SUBREG
 	  && REG_P (SUBREG_REG (src))
+	  && REGNO (SUBREG_REG (src)) >= FIRST_PSEUDO_REGISTER
 	  && GET_MODE (SUBREG_REG (src)) == use_mode
 	  && subreg_lowpart_p (src)
 	  && all_uses_available_at (def_insn, use_insn))
@@ -1119,6 +1120,7 @@ forward_propagate_subreg (df_ref use, rtx def_insn, rtx def_set)
       if ((GET_CODE (src) == ZERO_EXTEND
 	   || GET_CODE (src) == SIGN_EXTEND)
 	  && REG_P (XEXP (src, 0))
+	  && REGNO (XEXP (src, 0)) >= FIRST_PSEUDO_REGISTER
 	  && GET_MODE (XEXP (src, 0)) == use_mode
 	  && !free_load_extend (src, def_insn)
 	  && all_uses_available_at (def_insn, use_insn))