rs6000.c (rs6000_adjust_atomic_subword): Calculate correct shift value in little-endian mode.

	* config/rs6000/rs6000.c (rs6000_adjust_atomic_subword): Calculate
	correct shift value in little-endian mode.

From-SVN: r199935

gcc/ChangeLog

+2013-06-11  Anton Blanchard  <anton@samba.org>
+
+	* config/rs6000/rs6000.c (rs6000_adjust_atomic_subword): Calculate
+	correct shift value in little-endian mode.
+
 2013-06-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/56564

gcc/config/rs6000/rs6000.c

@@ -17881,6 +17881,7 @@ rs6000_adjust_atomic_subword (rtx orig_mem, rtx *pshift, rtx *pmask)
   shift = gen_reg_rtx (SImode);
   addr = gen_lowpart (SImode, addr);
   emit_insn (gen_rlwinm (shift, addr, GEN_INT (3), GEN_INT (shift_mask)));
+  if (WORDS_BIG_ENDIAN)
     shift = expand_simple_binop (SImode, XOR, shift, GEN_INT (shift_mask),
 			         shift, 1, OPTAB_LIB_WIDEN);
   *pshift = shift;