SIMD Overlay: inline deprecated methods (swiftlang#23250)

troughton · stephentyrone · commit e0c9a6e17c34 · 2019-03-22T16:19:53.000-04:00
On Swift 5, using the deprecated `SIMD.init(_ scalar: Scalar)` initialiser rather than `SIMD.init(repeating scalar: Scalar)` will cause the type to fail to be specialised, resulting in performance degradation. Mark this method and `static prefix func -` as `@_transparent` to ensure they are correctly specialised.
diff --git a/stdlib/public/Darwin/simd/simd.swift.gyb b/stdlib/public/Darwin/simd/simd.swift.gyb
@@ -18,6 +18,7 @@ import Darwin
 
 public extension SIMD {
   @available(swift, deprecated:5, renamed: "init(repeating:)")
+  @_transparent
   init(_ scalar: Scalar) { self.init(repeating: scalar) }
 }
 
@@ -35,6 +36,7 @@ internal extension SIMD4 {
 
 public extension SIMD where Scalar : FixedWidthInteger {
   @available(swift, deprecated:5, message: "use 0 &- rhs")
+  @_transparent
   static prefix func -(rhs: Self) -> Self { return 0 &- rhs }
 }
 

Original file line number	Diff line number	Diff line change
`@@ -18,6 +18,7 @@ import Darwin`
`18`	`18`
`19`	`19`	`public extension SIMD {`
`20`	`20`	`@available(swift, deprecated:5, renamed: "init(repeating:)")`
	`21`	`+ @_transparent`
`21`	`22`	`init(_ scalar: Scalar) { self.init(repeating: scalar) }`
`22`	`23`	`}`
`23`	`24`
`@@ -35,6 +36,7 @@ internal extension SIMD4 {`
`35`	`36`
`36`	`37`	`public extension SIMD where Scalar : FixedWidthInteger {`
`37`	`38`	`@available(swift, deprecated:5, message: "use 0 &- rhs")`
	`39`	`+ @_transparent`
`38`	`40`	`static prefix func -(rhs: Self) -> Self { return 0 &- rhs }`
`39`	`41`	`}`
`40`	`42`