Many supported cores implement fusion of AES instructions.

Many supported cores implement fusion of AES instructions.  When fusion
happens it can give a significant performance gain.  If not, scheduling
fusion candidates next to each other has almost no effect on performance.
Due to the high benefit/low cost it makes sense to enable AES fusion with
-mcpu=generic so that cores that support it always benefit.

    gcc/
	* config/aarch64/aarch64.c (generic_tunings): Add AES fusion.

From-SVN: r246395

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index eaf7650..a4d5a9a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2017-03-22  Wilco Dijkstra  <wdijkstr@arm.com>
+
+       * config/aarch64/aarch64.c (generic_tunings): Add AES fusion.
+
 2017-03-21  Aaron Sawdey  <acsawdey@linux.vnet.ibm.com>
 
        PR target/80123

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index a069427..eb0095d 100644 (file)
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -536,7 +536,7 @@ static const struct tune_params generic_tunings =
   &generic_approx_modes,
   4, /* memmov_cost  */
   2, /* issue_rate  */
-  AARCH64_FUSE_NOTHING, /* fusible_ops  */
+  (AARCH64_FUSE_AES_AESMC), /* fusible_ops  */
   8,   /* function_align.  */
   8,   /* jump_align.  */
   4,   /* loop_align.  */