---

yaml
---
r: 347407
b: refs/heads/master
c: b9b809c
h: refs/heads/master
i:
  347405: 61c2cbe
  347403: 5f522aa
  347399: 2ca8ec1
  347391: 15a21f2

Author: swift-ci

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: b63e32aec648b30d2337c41599fc70aa4680cc5a
+refs/heads/master: b9b809c14e0e51f0044dc462823551c9039bb0f7
 refs/heads/master-next: 203b3026584ecad859eb328b2e12490099409cd5
 refs/tags/osx-passed: b6b74147ef8a386f532cf9357a1bde006e552c54
 refs/tags/swift-2.2-SNAPSHOT-2015-12-01-a: 6bb18e013c2284f2b45f5f84f2df2887dc0f7dea

trunk/stdlib/public/core/FloatingPoint.swift

@@ -230,7 +230,6 @@ public protocol FloatingPoint : SignedNumeric, Strideable, Hashable
   ///     the initializer has the same magnitude as `magnitudeOf`.
   init(signOf: Self, magnitudeOf: Self)
 
-  
   /// Creates a new value, rounded to the closest possible representation.
   ///
   /// If two representable values are equally close, the result is the value

trunk/stdlib/public/core/FloatingPointTypes.swift.gyb

@@ -973,6 +973,15 @@ extension ${Self}: BinaryFloatingPoint {
 %end
   }
 
+  //  For core standard library floating-point types, LLVM can lower copysign
+  //  for us; this gets somewhat better codegen than the generic implementation,
+  //  but more importantly allows it to participate in other optimizations
+  //  at the LLVM level.
+  @_transparent
+  public init(signOf sign: ${Self}, magnitudeOf mag: ${Self}) {
+    _value = Builtin.int_copysign_FPIEEE${bits}(mag._value, sign._value)
+  }
+
   /// Rounds the value to an integral value using the specified rounding rule.
   ///
   /// The following example rounds a value using four different rounding rules: