aarch64-simd.md: correct flags text for MIN_EXPR replacement.

2018-07-05  Indu Bhagat  <indu.bhagat@oracle.com> 

        * config/aarch64/aarch64-simd.md: correct flags text for
        MIN_EXPR replacement.

From-SVN: r262458

gcc/ChangeLog

+2018-07-05  Indu Bhagat  <indu.bhagat@oracle.com> 
+
+	* config/aarch64/aarch64-simd.md: correct flags text for 
+	MIN_EXPR replacement.
+
 2018-07-05  James Clarke  <jrtc27@jrtc27.com>
 
 	* configure: Regenerated.

gcc/config/aarch64/aarch64-simd.md

@@ -2233,8 +2233,9 @@
 ;; Max/Min are introduced by idiom recognition by GCC's mid-end.  An
 ;; expression like:
 ;;      a = (b < c) ? b : c;
-;; is idiom-matched as MIN_EXPR<b,c> only if -ffinite-math-only is enabled
-;; either explicitly or indirectly via -ffast-math.
+;; is idiom-matched as MIN_EXPR<b,c> only if -ffinite-math-only and
+;; -fno-signed-zeros are enabled either explicitly or indirectly via
+;; -ffast-math.
 ;;
 ;; MIN_EXPR and MAX_EXPR eventually map to 'smin' and 'smax' in RTL.
 ;; The 'smax' and 'smin' RTL standard pattern names do not specify which