[ARM] Tie operand 1 to operand 0 in AESMC pattern when fusing AES/AESMC

	* config/arm/arm.c (arm_fusion_enabled_p): New function.
	* config/arm/arm-protos.h (arm_fusion_enabled_p): Declare prototype.
	* config/arm/crypto.md (crypto_<crypto_pattern>, CRYPTO_UNARY):
	Add "=w,0" alternative.  Enable it when AES/AESMC fusion is enabled.

From-SVN: r236982

gcc/ChangeLog

+2016-06-01  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	* config/arm/arm.c (arm_fusion_enabled_p): New function.
+	* config/arm/arm-protos.h (arm_fusion_enabled_p): Declare prototype.
+	* config/arm/crypto.md (crypto_<crypto_pattern>, CRYPTO_UNARY):
+	Add "=w,0" alternative.  Enable it when AES/AESMC fusion is enabled.
+
 2016-06-01  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* tree-vect-loop.c (vect_determine_vectorization_factor): Also take

gcc/config/arm/arm-protos.h

@@ -321,6 +321,7 @@ extern int vfp3_const_double_for_bits (rtx);
 
 extern void arm_emit_coreregs_64bit_shift (enum rtx_code, rtx, rtx, rtx, rtx,
 					   rtx);
+extern bool arm_fusion_enabled_p (tune_params::fuse_ops);
 extern bool arm_valid_symbolic_address_p (rtx);
 extern bool arm_validize_comparison (rtx *, rtx *, rtx *);
 #endif /* RTX_CODE */

gcc/config/arm/arm.c

@@ -29858,6 +29858,13 @@ aarch_macro_fusion_pair_p (rtx_insn* prev, rtx_insn* curr)
   return false;
 }
 
+/* Return true iff the instruction fusion described by OP is enabled.  */
+bool
+arm_fusion_enabled_p (tune_params::fuse_ops op)
+{
+  return current_tune->fusible_ops & op;
+}
+
 /* Implement the TARGET_ASAN_SHADOW_OFFSET hook.  */
 
 static unsigned HOST_WIDE_INT

gcc/config/arm/crypto.md

@@ -18,14 +18,27 @@
 ;; along with GCC; see the file COPYING3.  If not see
 ;; <http://www.gnu.org/licenses/>.
 
+
+;; When AES/AESMC fusion is enabled we want the register allocation to
+;; look like:
+;;    AESE Vn, _
+;;    AESMC Vn, Vn
+;; So prefer to tie operand 1 to operand 0 when fusing.
+
 (define_insn "crypto_<crypto_pattern>"
-  [(set (match_operand:<crypto_mode> 0 "register_operand" "=w")
+  [(set (match_operand:<crypto_mode> 0 "register_operand" "=w,w")
         (unspec:<crypto_mode> [(match_operand:<crypto_mode> 1
-                       "register_operand" "w")]
+                       "register_operand" "0,w")]
          CRYPTO_UNARY))]
   "TARGET_CRYPTO"
   "<crypto_pattern>.<crypto_size_sfx>\\t%q0, %q1"
-  [(set_attr "type" "<crypto_type>")]
+  [(set_attr "type" "<crypto_type>")
+   (set_attr_alternative "enabled"
+     [(if_then_else (match_test
+		       "arm_fusion_enabled_p (tune_params::FUSE_AES_AESMC)")
+		     (const_string "yes" )
+		     (const_string "no"))
+      (const_string "yes")])]
 )
 
 (define_insn "crypto_<crypto_pattern>"