Adjust Float16 availability for Swift 5.4 toolchains.

In older toolchains, Float16 is marked unavailable on all mac targets; starting with the 5.4 toolchain, it is available starting in macOS 11.0 when targeting Apple Silicon.

Sources/RealModule/Float16+Real.swift

@@ -9,9 +9,177 @@
 //
 //===----------------------------------------------------------------------===//
 
-#if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
 import _NumericsShims
 
+// When building with a Swift 5.4 or later toolchain, Float16 is available on
+// non-x86 macOS from 11.0 onward.
+#if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
+
+@available(macOS 11.0, iOS 14.0, tvOS 14.0, watchOS 7.0, *)
+extension Float16: Real {
+  @_transparent
+  public static func cos(_ x: Float16) -> Float16 {
+    Float16(.cos(Float(x)))
+  }
+
+  @_transparent
+  public static func sin(_ x: Float16) -> Float16 {
+    Float16(.sin(Float(x)))
+  }
+
+  @_transparent
+  public static func tan(_ x: Float16) -> Float16 {
+    Float16(.tan(Float(x)))
+  }
+
+  @_transparent
+  public static func acos(_ x: Float16) -> Float16 {
+    Float16(.acos(Float(x)))
+  }
+
+  @_transparent
+  public static func asin(_ x: Float16) -> Float16 {
+    Float16(.asin(Float(x)))
+  }
+
+  @_transparent
+  public static func atan(_ x: Float16) -> Float16 {
+    Float16(.atan(Float(x)))
+  }
+
+  @_transparent
+  public static func cosh(_ x: Float16) -> Float16 {
+    Float16(.cosh(Float(x)))
+  }
+
+  @_transparent
+  public static func sinh(_ x: Float16) -> Float16 {
+    Float16(.sinh(Float(x)))
+  }
+
+  @_transparent
+  public static func tanh(_ x: Float16) -> Float16 {
+    Float16(.tanh(Float(x)))
+  }
+
+  @_transparent
+  public static func acosh(_ x: Float16) -> Float16 {
+    Float16(.acosh(Float(x)))
+  }
+
+  @_transparent
+  public static func asinh(_ x: Float16) -> Float16 {
+    Float16(.asinh(Float(x)))
+  }
+
+  @_transparent
+  public static func atanh(_ x: Float16) -> Float16 {
+    Float16(.atanh(Float(x)))
+  }
+
+  @_transparent
+  public static func exp(_ x: Float16) -> Float16 {
+    Float16(.exp(Float(x)))
+  }
+
+  @_transparent
+  public static func expMinusOne(_ x: Float16) -> Float16 {
+    Float16(.expMinusOne(Float(x)))
+  }
+
+  @_transparent
+  public static func log(_ x: Float16) -> Float16 {
+    Float16(.log(Float(x)))
+  }
+
+  @_transparent
+  public static func log(onePlus x: Float16) -> Float16 {
+    Float16(.log(onePlus: Float(x)))
+  }
+
+  @_transparent
+  public static func erf(_ x: Float16) -> Float16 {
+    Float16(.erf(Float(x)))
+  }
+
+  @_transparent
+  public static func erfc(_ x: Float16) -> Float16 {
+    Float16(.erfc(Float(x)))
+  }
+
+  @_transparent
+  public static func exp2(_ x: Float16) -> Float16 {
+    Float16(.exp2(Float(x)))
+  }
+
+  @_transparent
+  public static func exp10(_ x: Float16) -> Float16 {
+    Float16(.exp10(Float(x)))
+  }
+
+  @_transparent
+  public static func hypot(_ x: Float16, _ y: Float16) -> Float16 {
+    if x.isInfinite || y.isInfinite { return .infinity }
+    let xf = Float(x)
+    let yf = Float(y)
+    return Float16(.sqrt(xf*xf + yf*yf))
+  }
+
+  @_transparent
+  public static func gamma(_ x: Float16) -> Float16 {
+    Float16(.gamma(Float(x)))
+  }
+
+  @_transparent
+  public static func log2(_ x: Float16) -> Float16 {
+    Float16(.log2(Float(x)))
+  }
+
+  @_transparent
+  public static func log10(_ x: Float16) -> Float16 {
+    Float16(.log10(Float(x)))
+  }
+
+  @_transparent
+  public static func pow(_ x: Float16, _ y: Float16) -> Float16 {
+    Float16(.pow(Float(x), Float(y)))
+  }
+
+  @_transparent
+  public static func pow(_ x: Float16, _ n: Int) -> Float16 {
+    // Float16 is simpler than Float or Double, because the range of
+    // "interesting" exponents is pretty small; anything outside of
+    // -22707 ... 34061 simply overflows or underflows for every
+    // x that isn't zero or one. This whole range is representable
+    // as Float, so we can just use powf as long as we're a little
+    // bit (get it?) careful to preserve parity.
+    let clamped = min(max(n, -0x10000), 0x10000) | (n & 1)
+    return Float16(libm_powf(Float(x), Float(clamped)))
+  }
+
+  @_transparent
+  public static func root(_ x: Float16, _ n: Int) -> Float16 {
+    Float16(.root(Float(x), n))
+  }
+
+  @_transparent
+  public static func atan2(y: Float16, x: Float16) -> Float16 {
+    Float16(.atan2(y: Float(y), x: Float(x)))
+  }
+
+  #if !os(Windows)
+  @_transparent
+  public static func logGamma(_ x: Float16) -> Float16 {
+    Float16(.logGamma(Float(x)))
+  }
+  #endif
+}
+
+// When building with older Swift toolchains for macOS, Float16 is not
+// available. We will drop support for these older toolchains at some
+// future point and remove this duplication.
+#elseif swift(>=5.3) && !(os(macOS) || targetEnvironment(macCatalyst))
+
 @available(iOS 14.0, tvOS 14.0, watchOS 7.0, *)
 extension Float16: Real {
   @_transparent
@@ -171,4 +339,5 @@ extension Float16: Real {
   }
   #endif
 }
+
 #endif

Sources/_TestSupport/RealTestSupport.swift

@@ -15,8 +15,8 @@ public protocol FixedWidthFloatingPoint: BinaryFloatingPoint
 where Exponent: FixedWidthInteger,
       RawSignificand: FixedWidthInteger { }
 
-#if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
-@available(iOS 14.0, watchOS 14.0, tvOS 7.0, *)
+#if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
+@available(macOS 11.0, iOS 14.0, watchOS 14.0, tvOS 7.0, *)
 extension Float16: FixedWidthFloatingPoint { }
 #endif
 

Tests/RealTests/ElementaryFunctionChecks.swift

@@ -130,9 +130,9 @@ internal extension Real where Self: BinaryFloatingPoint {
 
 final class ElementaryFunctionChecks: XCTestCase {
 
-  #if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
+  #if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
   func testFloat16() {
-    if #available(iOS 14.0, watchOS 14.0, tvOS 7.0, *) {
+    if #available(macOS 11.0, iOS 14.0, watchOS 14.0, tvOS 7.0, *) {
       Float16.elementaryFunctionChecks()
       Float16.realFunctionChecks()
     }

Tests/RealTests/IntegerExponentTests.swift

@@ -77,8 +77,8 @@ internal extension Real where Self: FixedWidthFloatingPoint {
   }
 }
 
-#if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
-@available(iOS 14.0, watchOS 14.0, tvOS 7.0, *)
+#if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
+@available(macOS 11.0, iOS 14.0, watchOS 14.0, tvOS 7.0, *)
 extension Float16 {
   static func testIntegerExponent() {
     testIntegerExponentCommon()
@@ -174,9 +174,11 @@ extension Double {
 
 final class IntegerExponentTests: XCTestCase {
 
-  #if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
+  #if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
   func testFloat16() {
-    Float16.testIntegerExponent()
+    if #available(macOS 11.0, iOS 14.0, watchOS 14.0, tvOS 7.0, *) {
+      Float16.testIntegerExponent()
+    }
   }
   #endif
 

Tests/WindowsMain.swift

@@ -32,24 +32,15 @@ extension RealTests.ApproximateEqualityTests {
   ])
 }
 
-#if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
+#if swift(>=5.4) && !((os(macOS) || targetEnvironment(macCatalyst)) && arch(x86_64))
 extension ElementaryFunctionChecks {
   static var all = testCase([
     ("testFloat16", ElementaryFunctionChecks.testFloat16),
     ("testFloat", ElementaryFunctionChecks.testFloat),
     ("testDouble", ElementaryFunctionChecks.testDouble),
   ])
 }
-#else
-extension ElementaryFunctionChecks {
-  static var all = testCase([
-    ("testFloat", ElementaryFunctionChecks.testFloat),
-    ("testDouble", ElementaryFunctionChecks.testDouble),
-  ])
-}
-#endif
 
-#if swift(>=5.3) && !(os(macOS) || os(iOS) && targetEnvironment(macCatalyst))
 extension IntegerExponentTests {
   static var all = testCase([
     ("testFloat16", IntegerExponentTests.testFloat16),
@@ -58,6 +49,13 @@ extension IntegerExponentTests {
   ])
 }
 #else
+extension ElementaryFunctionChecks {
+  static var all = testCase([
+    ("testFloat", ElementaryFunctionChecks.testFloat),
+    ("testDouble", ElementaryFunctionChecks.testDouble),
+  ])
+}
+
 extension IntegerExponentTests {
   static var all = testCase([
     ("testFloat", IntegerExponentTests.testFloat),