SILGen: Stub unavailable @objc interop functions and thunks.

Part of rdar://107388493

Author: tshortli

lib/SILGen/SILGenBridging.cpp

@@ -1556,6 +1556,11 @@ void SILGenFunction::emitNativeToForeignThunk(SILDeclRef thunk) {
   assert(thunk.isForeign);
   SILDeclRef native = thunk.asForeign(false);
 
+  if (thunk.hasDecl()) {
+    if (shouldLowerToUnavailableCodeStub(thunk.getDecl()))
+      emitApplyOfUnavailableCodeReached();
+  }
+
   // If we're calling a native non-designated class initializer, we have to
   // discard the `self` object we were given, since
   // Swift convenience initializers only have allocating entry points that
@@ -2067,6 +2072,9 @@ void SILGenFunction::emitForeignToNativeThunk(SILDeclRef thunk) {
   auto nativeFnTy = F.getLoweredFunctionType();
   assert(nativeFnTy == nativeCI.SILFnType);
 
+  if (shouldLowerToUnavailableCodeStub(fd))
+    emitApplyOfUnavailableCodeReached();
+
   // Use the same generic environment as the native entry point.
   F.setGenericEnvironment(SGM.Types.getConstantGenericEnvironment(thunk));
 

lib/SILGen/SILGenDestructor.cpp

@@ -612,6 +612,9 @@ void SILGenFunction::emitObjCDestructor(SILDeclRef dtor) {
   if (dd->isImplicit())
     loc.markAutoGenerated();
 
+  if (shouldLowerToUnavailableCodeStub(dd))
+    emitApplyOfUnavailableCodeReached();
+
   SILValue selfValue = emitSelfDeclForDestructor(dd->getImplicitSelfDecl());
 
   // Create a basic block to jump to for the implicit destruction behavior

test/SILGen/unavailable_decl_optimization_stub_objc.swift

@@ -0,0 +1,58 @@
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -emit-silgen -module-name Test -parse-as-library %s -verify -unavailable-decl-optimization=stub | %FileCheck %s --check-prefixes=CHECK
+
+// REQUIRES: objc_interop
+
+import Foundation
+
+func foo() {}
+
+@available(*, unavailable)
+@objc public class C: NSObject {
+  // C.__allocating_init()
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCACycfC
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         {{%.*}} = function_ref @$s4Test1CCACycfcTD
+  // CHECK:       } // end sil function '$s4Test1CCACycfC'
+  //
+  // dynamic C.init()
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCACycfcTD
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         objc_method %0 : $C, #C.init!initializer.foreign
+  // CHECK:       } // end sil function '$s4Test1CCACycfcTD'
+  //
+  // C.init()
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCACycfc
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         {{%.*}} = function_ref @$s4Test3fooyyF
+  // CHECK:       } // end sil function '$s4Test1CCACycfc'
+  //
+  // @objc C.init()
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCACycfcTo
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         {{%.*}} = function_ref @$s4Test1CCACycfc
+  // CHECK:       } // end sil function '$s4Test1CCACycfcTo'
+  public override init() {
+    foo()
+  }
+
+  // C.__deallocating_deinit
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCfD
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         {{%.*}} = function_ref @$s4Test3fooyyF
+  // CHECK:       } // end sil function '$s4Test1CCfD'
+  //
+  // @objc C.__deallocating_deinit
+  // CHECK-LABEL: sil {{.*}} @$s4Test1CCfDTo
+  // CHECK:         [[FNREF:%.*]] = function_ref @$ss31_diagnoseUnavailableCodeReacheds5NeverOyF
+  // CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+  // CHECK:         {{%.*}} = function_ref @$s4Test1CCfD
+  // CHECK:       } // end sil function '$s4Test1CCfDTo'
+  deinit {
+    foo()
+  }
+}