[test] IRGen: add a test for generating linker directive symbols $ld$hide

Author: nkcsgexi

test/IRGen/original-defined-attr-linker-hide.swift

@@ -0,0 +1,26 @@
+// RUN: %target-swift-frontend -swift-version 4 -enforce-exclusivity=checked %s -emit-ir -module-name CurrentModule -D CURRENT_MODULE | %FileCheck %s --check-prefix=CHECK-SAMEMAJOR --check-prefix=CHECK-DIFFMAJOR
+
+@available(OSX 10.8, *)
+@_originallyDefinedIn(module: "OriginalModule", macOS 10.10)
+public struct Entity {
+  public func addEntity(_ e: Entity) {}
+  public func removeEntity(_ e: Entity) {}
+}
+
+// CHECK-SAMEMAJOR: $ld$hide$os10.8$_$s14OriginalModule6EntityVN
+// CHECK-SAMEMAJOR: $ld$hide$os10.9$_$s14OriginalModule6EntityVN
+// CHECK-SAMEMAJOR-NOT: $ld$hide$os10.10$_$s14OriginalModule6EntityVN
+
+@available(OSX 9.8, *)
+@_originallyDefinedIn(module: "OriginalModule", macOS 10.10)
+public struct OldEntity {
+  public func addEntity(_ e: Entity) {}
+  public func removeEntity(_ e: Entity) {}
+}
+
+// CHECK-DIFFMAJOR: $ld$hide$os9.9$_$s14OriginalModule9OldEntityVN
+// CHECK-DIFFMAJOR: $ld$hide$os9.13$_$s14OriginalModule9OldEntityVN
+// CHECK-DIFFMAJOR: $ld$hide$os9.30$_$s14OriginalModule9OldEntityVN
+// CHECK-DIFFMAJOR: $ld$hide$os10.8$_$s14OriginalModule9OldEntityVN
+// CHECK-DIFFMAJOR: $ld$hide$os10.9$_$s14OriginalModule9OldEntityVN
+// CHECK-DIFFMAJOR-NOT: $ld$hide$os10.10$_$s14OriginalModule9OldEntityVN

test/IRGen/original-defined-attr.swift

@@ -3,19 +3,22 @@
 
 #if CURRENT_MODULE
 
+@available(OSX 10.8, *)
 @_originallyDefinedIn(module: "OriginalModule", macOS 10.15)
 public struct Entity {
 	public func addEntity(_ e: Entity) {}
 	public func removeEntity(_ e: Entity) {}
 }
 
+@available(OSX 10.8, *)
 @_originallyDefinedIn(module: "OriginalModule", macOS 10.15)
 public protocol Movable {
 	func MovableFuncFoo()
 }
 
 public protocol Unmoveable {}
 
+@available(OSX 10.8, *)
 @_originallyDefinedIn(module: "OriginalModule", macOS 10.15)
 public class MovedClass: Movable, Unmoveable {
 	public func MovableFuncFoo() {}