diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5c95b16f364..9981ddd8359 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2018-12-11  Richard Earnshaw  <rearnsha@arm.com>
+
+	PR target/37369
+	* config/aarch64/iterators.md (sizem1): Add sizes for SFmode and DFmode.
+	(Vbtype): Add SFmode mapping.
+	* config/aarch64/aarch64.md (copysigndf3, copysignsf3): Delete.
+	(copysign<GPF:mode>3): New expand pattern.
+	(copysign<GPF:mode>3_insn): New insn pattern.
+
 2018-12-11  Richard Biener  <rguenther@suse.de>
 
 	* ccmp.c (ccmp_candidate_p): Use GIMPLE API properly.
diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 82af4d47f78..6657316c5dd 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -222,6 +222,7 @@
     UNSPEC_FADDA
     UNSPEC_REV_SUBREG
     UNSPEC_SPECULATION_TRACKER
+    UNSPEC_COPYSIGN
 ])
 
 (define_c_enum "unspecv" [
@@ -5987,49 +5988,47 @@
 ;;   LDR d2, #(1 << 63)
 ;;   BSL v2.8b, [y], [x]
 ;;
-;; or another, equivalent, sequence using one of BSL/BIT/BIF.
-;; aarch64_simd_bsldf will select the best suited of these instructions
-;; to generate based on register allocation, and knows how to partially
-;; constant fold based on the values of X and Y, so expand through that.
+;; or another, equivalent, sequence using one of BSL/BIT/BIF.  Because
+;; we expect these operations to nearly always operate on
+;; floating-point values, we do not want the operation to be
+;; simplified into a bit-field insert operation that operates on the
+;; integer side, since typically that would involve three inter-bank
+;; register copies.  As we do not expect copysign to be followed by
+;; other logical operations on the result, it seems preferable to keep
+;; this as an unspec operation, rather than exposing the underlying
+;; logic to the compiler.
 
-(define_expand "copysigndf3"
-  [(match_operand:DF 0 "register_operand")
-   (match_operand:DF 1 "register_operand")
-   (match_operand:DF 2 "register_operand")]
+(define_expand "copysign<GPF:mode>3"
+  [(match_operand:GPF 0 "register_operand")
+   (match_operand:GPF 1 "register_operand")
+   (match_operand:GPF 2 "register_operand")]
   "TARGET_FLOAT && TARGET_SIMD"
 {
-  rtx mask = gen_reg_rtx (DImode);
-  emit_move_insn (mask, GEN_INT (HOST_WIDE_INT_1U << 63));
-  emit_insn (gen_aarch64_simd_bsldf (operands[0], mask,
-				     operands[2], operands[1]));
+  rtx bitmask = gen_reg_rtx (<V_INT_EQUIV>mode);
+  emit_move_insn (bitmask, GEN_INT (HOST_WIDE_INT_M1U
+				    << (GET_MODE_BITSIZE (<MODE>mode) - 1)));
+  emit_insn (gen_copysign<mode>3_insn (operands[0], operands[1], operands[2],
+				       bitmask));
   DONE;
 }
 )
 
-;; As above, but we must first get to a 64-bit value if we wish to use
-;; aarch64_simd_bslv2sf.
-
-(define_expand "copysignsf3"
-  [(match_operand:SF 0 "register_operand")
-   (match_operand:SF 1 "register_operand")
-   (match_operand:SF 2 "register_operand")]
+(define_insn "copysign<GPF:mode>3_insn"
+  [(set (match_operand:GPF 0 "register_operand" "=w,w,w,r")
+	(unspec:GPF [(match_operand:GPF 1 "register_operand" "w,0,w,r")
+		     (match_operand:GPF 2 "register_operand" "w,w,0,0")
+		     (match_operand:<V_INT_EQUIV> 3 "register_operand" "0,w,w,X")]
+	 UNSPEC_COPYSIGN))]
   "TARGET_FLOAT && TARGET_SIMD"
-{
-  rtx v_bitmask = gen_reg_rtx (V2SImode);
-
-  /* Juggle modes to get us in to a vector mode for BSL.  */
-  rtx op1 = lowpart_subreg (DImode, operands[1], SFmode);
-  rtx op2 = lowpart_subreg (V2SFmode, operands[2], SFmode);
-  rtx tmp = gen_reg_rtx (V2SFmode);
-  emit_move_insn (v_bitmask,
-		  aarch64_simd_gen_const_vector_dup (V2SImode,
-						     HOST_WIDE_INT_M1U << 31));
-  emit_insn (gen_aarch64_simd_bslv2sf (tmp, v_bitmask, op2, op1));
-  emit_move_insn (operands[0], lowpart_subreg (SFmode, tmp, V2SFmode));
-  DONE;
-}
+  "@
+   bsl\\t%0.<Vbtype>, %2.<Vbtype>, %1.<Vbtype>
+   bit\\t%0.<Vbtype>, %2.<Vbtype>, %3.<Vbtype>
+   bif\\t%0.<Vbtype>, %1.<Vbtype>, %3.<Vbtype>
+   bfxil\\t%<w1>0, %<w1>1, #0, <sizem1>"
+  [(set_attr "type" "neon_bsl<q>,neon_bsl<q>,neon_bsl<q>,bfm")]
 )
 
+
 ;; For xorsign (x, y), we want to generate:
 ;;
 ;; LDR   d2, #1<<63
diff --git a/gcc/config/aarch64/iterators.md b/gcc/config/aarch64/iterators.md
index a80755734d6..ae75666167d 100644
--- a/gcc/config/aarch64/iterators.md
+++ b/gcc/config/aarch64/iterators.md
@@ -601,7 +601,8 @@
 (define_mode_attr sizen [(QI "8") (HI "16") (SI "32") (DI "64")])
 
 ;; Give the ordinal of the MSB in the mode
-(define_mode_attr sizem1 [(QI "#7") (HI "#15") (SI "#31") (DI "#63")])
+(define_mode_attr sizem1 [(QI "#7") (HI "#15") (SI "#31") (DI "#63")
+			  (HF "#15") (SF "#31") (DF "#63")])
 
 ;; Attribute to describe constants acceptable in logical operations
 (define_mode_attr lconst [(SI "K") (DI "L")])
@@ -687,7 +688,7 @@
 			  (V8HF "16b") (V2SF  "8b")
 			  (V4SF "16b") (V2DF  "16b")
 			  (DI   "8b")  (DF    "8b")
-			  (SI   "8b")])
+			  (SI   "8b")  (SF    "8b")])
 
 ;; Define element mode for each vector mode.
 (define_mode_attr VEL [(V8QI  "QI") (V16QI "QI") (VNx16QI "QI")