Test: Enhance TBDGen test coverage for the @_specialize attribute.

Author: tshortli

test/TBD/specialize_attr.swift

@@ -0,0 +1,51 @@
+// REQUIRES: VENDOR=apple
+
+// RUN: %target-swift-frontend -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s
+// RUN: %target-swift-frontend -enable-library-evolution -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s
+// RUN: %target-swift-frontend -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s -enable-testing
+// RUN: %target-swift-frontend -enable-library-evolution -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s -enable-testing
+
+// RUN: %target-swift-frontend -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing -O %s
+// RUN: %target-swift-frontend -enable-library-evolution -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing -O %s
+// RUN: %target-swift-frontend -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s -enable-testing -O
+// RUN: %target-swift-frontend -enable-library-evolution -emit-ir -o/dev/null -parse-as-library -module-name test -validate-tbd-against-ir=missing %s -enable-testing -O
+
+@_specialize(exported: false, where T == Int)
+@_specialize(exported: true, where T == Float)
+public func foo<T>(_ x : T) -> T { return x }
+
+@_specialize(exported: false, where T == Int)
+@_specialize(exported: true, where T == Float)
+internal func fooInternal<T>(_ x : T) -> T { return x }
+
+@_specialize(exported: false, where T == Int)
+@_specialize(exported: true, where T == Float)
+private func fooPrivate<T>(_ x : T) -> T { return x }
+
+public struct S {
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  public func foo<T>(_ x : T) -> T { return x }
+
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  internal func fooInternal<T>(_ x : T) -> T { return x }
+
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  private func fooPrivate<T>(_ x : T) -> T { return x }
+}
+
+public class C {
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  public func foo<T>(_ x : T) -> T { return x }
+
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  internal func fooInternal<T>(_ x : T) -> T { return x }
+
+  @_specialize(exported: false, where T == Int)
+  @_specialize(exported: true, where T == Float)
+  private func fooPrivate<T>(_ x : T) -> T { return x }
+}