[2/2] aarch64: Reimplement (R){ADD,SUB}HN2 patterns with standard RTL codes

Similar to the previous patch, this one converts the high-half versions of the patterns.
With this patch we can remove the UNSPEC_* codes involved entirely.

Bootstrapped and tested on aarch64-none-linux-gnu. Also tested on aarch64_be-none-elf.

gcc/ChangeLog:

	* config/aarch64/aarch64-simd.md (aarch64_<sur><addsub>hn2<mode>_insn_le):
	Rename and reimplement with RTL codes to...
	(aarch64_<optab>hn2<mode>_insn_le): .. This.
	(aarch64_r<optab>hn2<mode>_insn_le): New pattern.
	(aarch64_<sur><addsub>hn2<mode>_insn_be): Rename and reimplement with RTL
	codes to...
	(aarch64_<optab>hn2<mode>_insn_be): ... This.
	(aarch64_r<optab>hn2<mode>_insn_be): New pattern.
	(aarch64_<sur><addsub>hn2<mode>): Rename and adjust expander to...
	(aarch64_<optab>hn2<mode>): ... This.
	(aarch64_r<optab>hn2<mode>): New expander.
	* config/aarch64/iterators.md (UNSPEC_ADDHN, UNSPEC_RADDHN,
	UNSPEC_SUBHN, UNSPEC_RSUBHN): Delete unspecs.
	(ADDSUBHN): Delete.
	(sur): Remove handling of the above.
	(addsub): Likewise.

2 files changed, 82 insertions, 34 deletions

diff --git a/gcc/config/aarch64/aarch64-simd.md b/gcc/config/aarch64/aarch64-simd.md
index 421173e7..4603888 100644
--- a/gcc/config/aarch64/aarch64-simd.md
+++ b/gcc/config/aarch64/aarch64-simd.md
@@ -5014,44 +5014,105 @@
   }
 )
 
-(define_insn "aarch64_<sur><addsub>hn2<mode>_insn_le"
+(define_insn "aarch64_<optab>hn2<mode>_insn_le"
   [(set (match_operand:<VNARROWQ2> 0 "register_operand" "=w")
 	(vec_concat:<VNARROWQ2>
 	  (match_operand:<VNARROWQ> 1 "register_operand" "0")
-	  (unspec:<VNARROWQ> [(match_operand:VQN 2 "register_operand" "w")
-			      (match_operand:VQN 3 "register_operand" "w")]
-			     ADDSUBHN)))]
+	  (truncate:<VNARROWQ>
+	    (ashiftrt:VQN
+	      (ADDSUB:VQN (match_operand:VQN 2 "register_operand" "w")
+			  (match_operand:VQN 3 "register_operand" "w"))
+	      (match_operand:VQN 4 "aarch64_simd_shift_imm_vec_exact_top")))))]
   "TARGET_SIMD && !BYTES_BIG_ENDIAN"
-  "<sur><addsub>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
-  [(set_attr "type" "neon_<addsub>_halve_narrow_q")]
+  "<optab>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
+  [(set_attr "type" "neon_<optab>_halve_narrow_q")]
 )
 
-(define_insn "aarch64_<sur><addsub>hn2<mode>_insn_be"
+(define_insn "aarch64_r<optab>hn2<mode>_insn_le"
   [(set (match_operand:<VNARROWQ2> 0 "register_operand" "=w")
 	(vec_concat:<VNARROWQ2>
-	  (unspec:<VNARROWQ> [(match_operand:VQN 2 "register_operand" "w")
-			      (match_operand:VQN 3 "register_operand" "w")]
-			     ADDSUBHN)
+	  (match_operand:<VNARROWQ> 1 "register_operand" "0")
+	  (truncate:<VNARROWQ>
+	    (ashiftrt:VQN
+	      (plus:VQN
+		(ADDSUB:VQN (match_operand:VQN 2 "register_operand" "w")
+			    (match_operand:VQN 3 "register_operand" "w"))
+		(match_operand:VQN 4 "aarch64_simd_raddsubhn_imm_vec"))
+	      (match_operand:VQN 5 "aarch64_simd_shift_imm_vec_exact_top")))))]
+  "TARGET_SIMD && !BYTES_BIG_ENDIAN"
+  "r<optab>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
+  [(set_attr "type" "neon_<optab>_halve_narrow_q")]
+)
+
+(define_insn "aarch64_<optab>hn2<mode>_insn_be"
+  [(set (match_operand:<VNARROWQ2> 0 "register_operand" "=w")
+	(vec_concat:<VNARROWQ2>
+	  (truncate:<VNARROWQ>
+	    (ashiftrt:VQN
+	      (ADDSUB:VQN (match_operand:VQN 2 "register_operand" "w")
+			  (match_operand:VQN 3 "register_operand" "w"))
+	      (match_operand:VQN 4 "aarch64_simd_shift_imm_vec_exact_top")))
 	  (match_operand:<VNARROWQ> 1 "register_operand" "0")))]
   "TARGET_SIMD && BYTES_BIG_ENDIAN"
-  "<sur><addsub>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
-  [(set_attr "type" "neon_<addsub>_halve_narrow_q")]
+  "<optab>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
+  [(set_attr "type" "neon_<optab>_halve_narrow_q")]
+)
+
+(define_insn "aarch64_r<optab>hn2<mode>_insn_be"
+  [(set (match_operand:<VNARROWQ2> 0 "register_operand" "=w")
+	(vec_concat:<VNARROWQ2>
+	  (truncate:<VNARROWQ>
+	    (ashiftrt:VQN
+	      (plus:VQN
+		(ADDSUB:VQN (match_operand:VQN 2 "register_operand" "w")
+			    (match_operand:VQN 3 "register_operand" "w"))
+		(match_operand:VQN 4 "aarch64_simd_raddsubhn_imm_vec"))
+	      (match_operand:VQN 5 "aarch64_simd_shift_imm_vec_exact_top")))
+	  (match_operand:<VNARROWQ> 1 "register_operand" "0")))]
+  "TARGET_SIMD && BYTES_BIG_ENDIAN"
+  "r<optab>hn2\\t%0.<V2ntype>, %2.<Vtype>, %3.<Vtype>"
+  [(set_attr "type" "neon_<optab>_halve_narrow_q")]
 )
 
-(define_expand "aarch64_<sur><addsub>hn2<mode>"
+(define_expand "aarch64_<optab>hn2<mode>"
   [(match_operand:<VNARROWQ2> 0 "register_operand")
    (match_operand:<VNARROWQ> 1 "register_operand")
-   (unspec [(match_operand:VQN 2 "register_operand")
-	    (match_operand:VQN 3 "register_operand")]
-	   ADDSUBHN)]
+   (ADDSUB:VQN (match_operand:VQN 2 "register_operand")
+	       (match_operand:VQN 3 "register_operand"))]
   "TARGET_SIMD"
   {
+    rtx shft
+      = aarch64_simd_gen_const_vector_dup (<MODE>mode,
+				GET_MODE_UNIT_BITSIZE (<MODE>mode) / 2);
     if (BYTES_BIG_ENDIAN)
-      emit_insn (gen_aarch64_<sur><addsub>hn2<mode>_insn_be (operands[0],
-				operands[1], operands[2], operands[3]));
+      emit_insn (gen_aarch64_<optab>hn2<mode>_insn_be (operands[0],
+				operands[1], operands[2], operands[3], shft));
     else
-      emit_insn (gen_aarch64_<sur><addsub>hn2<mode>_insn_le (operands[0],
-				operands[1], operands[2], operands[3]));
+      emit_insn (gen_aarch64_<optab>hn2<mode>_insn_le (operands[0],
+				operands[1], operands[2], operands[3], shft));
+    DONE;
+  }
+)
+
+(define_expand "aarch64_r<optab>hn2<mode>"
+  [(match_operand:<VNARROWQ2> 0 "register_operand")
+   (match_operand:<VNARROWQ> 1 "register_operand")
+   (ADDSUB:VQN (match_operand:VQN 2 "register_operand")
+	       (match_operand:VQN 3 "register_operand"))]
+  "TARGET_SIMD"
+  {
+    rtx shft
+      = aarch64_simd_gen_const_vector_dup (<MODE>mode,
+				GET_MODE_UNIT_BITSIZE (<MODE>mode) / 2);
+    rtx rnd
+      = aarch64_simd_gen_const_vector_dup (<MODE>mode,
+	HOST_WIDE_INT_1U << (GET_MODE_UNIT_BITSIZE (<MODE>mode) / 2 - 1));
+    if (BYTES_BIG_ENDIAN)
+      emit_insn (gen_aarch64_r<optab>hn2<mode>_insn_be (operands[0],
+				operands[1], operands[2], operands[3], rnd, shft));
+    else
+      emit_insn (gen_aarch64_r<optab>hn2<mode>_insn_le (operands[0],
+				operands[1], operands[2], operands[3], rnd, shft));
     DONE;
   }
 )
diff --git a/gcc/config/aarch64/iterators.md b/gcc/config/aarch64/iterators.md
index 861753f..4f1fd64 100644
--- a/gcc/config/aarch64/iterators.md
+++ b/gcc/config/aarch64/iterators.md
@@ -634,10 +634,6 @@
     UNSPEC_URHADD	; Used in aarch64-simd.md.
     UNSPEC_SHSUB	; Used in aarch64-simd.md.
     UNSPEC_UHSUB	; Used in aarch64-simd.md.
-    UNSPEC_ADDHN	; Used in aarch64-simd.md.
-    UNSPEC_RADDHN	; Used in aarch64-simd.md.
-    UNSPEC_SUBHN	; Used in aarch64-simd.md.
-    UNSPEC_RSUBHN	; Used in aarch64-simd.md.
     UNSPEC_SQDMULH	; Used in aarch64-simd.md.
     UNSPEC_SQRDMULH	; Used in aarch64-simd.md.
     UNSPEC_PMUL		; Used in aarch64-simd.md.
@@ -2609,9 +2605,6 @@
 (define_int_iterator DOTPROD_I8MM [UNSPEC_USDOT UNSPEC_SUDOT])
 (define_int_iterator DOTPROD_US_ONLY [UNSPEC_USDOT])
 
-(define_int_iterator ADDSUBHN [UNSPEC_ADDHN UNSPEC_RADDHN
-			       UNSPEC_SUBHN UNSPEC_RSUBHN])
-
 (define_int_iterator FMAXMIN_UNS [UNSPEC_FMAX UNSPEC_FMIN
 				  UNSPEC_FMAXNM UNSPEC_FMINNM])
 
@@ -3355,9 +3348,7 @@
 (define_int_attr sur [(UNSPEC_SHADD "s") (UNSPEC_UHADD "u")
 		      (UNSPEC_SRHADD "sr") (UNSPEC_URHADD "ur")
 		      (UNSPEC_SHSUB "s") (UNSPEC_UHSUB "u")
-		      (UNSPEC_ADDHN "") (UNSPEC_RADDHN "r")
 		      (UNSPEC_SADALP "s") (UNSPEC_UADALP "u")
-		      (UNSPEC_SUBHN "") (UNSPEC_RSUBHN "r")
 		      (UNSPEC_USQADD "us") (UNSPEC_SUQADD "su")
 		      (UNSPEC_SSLI  "s") (UNSPEC_USLI  "u")
 		      (UNSPEC_SSRI  "s") (UNSPEC_USRI  "u")
@@ -3416,11 +3407,7 @@
 			 (UNSPEC_SRHADD "add")
 			 (UNSPEC_URHADD "add")
 			 (UNSPEC_SHSUB "sub")
-			 (UNSPEC_UHSUB "sub")
-			 (UNSPEC_ADDHN "add")
-			 (UNSPEC_SUBHN "sub")
-			 (UNSPEC_RADDHN "add")
-			 (UNSPEC_RSUBHN "sub")])
+			 (UNSPEC_UHSUB "sub")])
 
 ;; BSL variants: first commutative operand.
 (define_int_attr bsl_1st [(1 "w") (2 "0")])