AST: Fix Decl::isUnreachableAtRuntime() for obsolete decls in unavailable decls.

Author: tshortli

lib/AST/Availability.cpp

@@ -716,16 +716,27 @@ bool Decl::isUnreachableAtRuntime() const {
   if (isa<ClangModuleUnit>(getDeclContext()->getModuleScopeContext()))
     return false;
 
-  auto unavailableAttrAndDecl =
-      getSemanticUnavailableAttr(/*ignoreAppExtensions=*/true);
-  if (!unavailableAttrAndDecl)
+  if (auto *parent =
+          AvailabilityInference::parentDeclForInferredAvailability(this)) {
+    if (parent->isUnreachableAtRuntime())
+      return true;
+  }
+
+  auto *unavailableAttr = getUnavailableAttr(/*ignoreAppExtensions=*/true);
+  if (!unavailableAttr)
+    return false;
+
+  // getUnavailableAttr() can return an @available attribute that is
+  // obsoleted for certain deployment targets or language modes. These decls
+  // can still be reached by code in other modules that is compiled with
+  // a different deployment target or language mode.
+  if (!unavailableAttr->isUnconditionallyUnavailable())
     return false;
 
-  // getSemanticUnavailableAttr() can return an @available attribute that makes
-  // its declaration unavailable conditionally due to deployment target. Only
+  // getUnavailableAttr() can return an @available attribute that makes its
+  // declaration unavailable conditionally due to deployment target. Only
   // stub or skip a declaration that is unavailable regardless of deployment
   // target.
-  auto *unavailableAttr = unavailableAttrAndDecl->first;
   if (!unavailableAttr->isUnconditionallyUnavailable())
     return false;
 

test/IRGen/unavailable_decl_optimization_complete_nested_type.swift

@@ -1,35 +1,38 @@
-// RUN: %target-swift-frontend -parse-as-library -module-name Test -validate-tbd-against-ir=missing -unavailable-decl-optimization=none %s -emit-ir | %FileCheck %s --check-prefixes=CHECK,CHECK-NO-STRIP
+// RUN: %target-swift-frontend -parse-as-library -module-name Test -validate-tbd-against-ir=missing -unavailable-decl-optimization=none %s -emit-ir | %FileCheck %s --check-prefixes=CHECK-NO-STRIP
 
-// RUN: %target-swift-frontend -parse-as-library -module-name Test -validate-tbd-against-ir=missing -unavailable-decl-optimization=complete %s -emit-ir | %FileCheck %s --check-prefixes=CHECK,CHECK-STRIP
+// RUN: %target-swift-frontend -parse-as-library -module-name Test -validate-tbd-against-ir=missing -unavailable-decl-optimization=complete %s -emit-ir | %FileCheck %s --implicit-check-not=unavailableFuncWithNestedObsoleteType --implicit-check-not=unavailableFuncWithNestedType --implicit-check-not=NestedInExtension
+
+// CHECK-NO-STRIP-DAG: s4Test29unavailableFuncWithNestedType
+// CHECK-NO-STRIP-DAG: s4Test29unavailableFuncWithNestedTypeyyF0E10InFunction
 
-// CHECK-NO-STRIP: s4Test29unavailableFuncWithNestedTypeyyF
-// CHECK-STRIP-NOT: s4Test29unavailableFuncWithNestedTypeyyF
 @available(*, unavailable)
 public func unavailableFuncWithNestedType() {
   struct NestedInFunction {
-    // s4Test29unavailableFuncWithNestedTypeyyF0E10InFunctionL_VADycfC
     init() {}
   }
 
   _ = NestedInFunction()
 }
 
-// CHECK-NO-STRIP: s4Test29unavailableFuncWithNestedTypeyyF0E10InFunctionL_VADycfC
-// CHECK-STRIP-NOT: s4Test29unavailableFuncWithNestedTypeyyF0E10InFunctionL_VADycfC
+// CHECK-NO-STRIP-DAG: s4Test37unavailableFuncWithNestedObsoleteType
+// CHECK-NO-STRIP-DAG: s4Test37unavailableFuncWithNestedObsoleteTypeyyF0E10InFunction
+
+@available(*, unavailable)
+public func unavailableFuncWithNestedObsoleteType() {
+  @available(swift, obsoleted: 4)
+  struct NestedInFunction {
+    init() {}
+  }
+}
 
 public struct S {}
 
+// CHECK-NO-STRIP-DAG: s4Test1SV17NestedInExtension
+
 extension S {
   @available(*, unavailable)
   public struct NestedInExtension {
-    // CHECK-NO-STRIP: s4Test1SV17NestedInExtensionV6methodyyF
-    // CHECK-STRIP-NOT: s4Test1SV17NestedInExtensionV6methodyyF
     public func method() {}
   }
 }
 
-// CHECK-NO-STRIP: s4Test1SV17NestedInExtensionVMa
-// CHECK-STRIP-NOT: s4Test1SV17NestedInExtensionVMa
-
-// CHECK-NO-STRIP: s4Test29unavailableFuncWithNestedTypeyyF0E10InFunctionL_VMa
-// CHECK-STRIP-NOT: s4Test29unavailableFuncWithNestedTypeyyF0E10InFunctionL_VMa

test/SILGen/unavailable_decl_optimization_stub.swift

@@ -12,6 +12,37 @@ public func unavailableFunc() -> S {
   return S()
 }
 
+// CHECK-LABEL: sil{{.*}}@$s4Test025unavailableFuncWithNestedC0yyF
+// CHECK:         [[FNREF:%.*]] = function_ref @$[[DIAGNOSEFN:(ss31_diagnoseUnavailableCodeReacheds5NeverOyF|ss31_diagnoseUnavailableCodeReacheds5NeverOyFTwb)]] : $@convention(thin) () -> Never
+// CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+// CHECK:         function_ref @$s4Test025unavailableFuncWithNestedC0yyF6nestedL_SiyF
+// CHECK:       } // end sil function '$s4Test025unavailableFuncWithNestedC0yyF'
+@available(*, unavailable)
+public func unavailableFuncWithNestedFunc() {
+  func nested() -> Int { 1 }
+  _ = nested()
+}
+
+// CHECK-LABEL: sil{{.*}}@$s4Test025unavailableFuncWithNestedC0yyF6nestedL_SiyF
+// CHECK:         [[FNREF:%.*]] = function_ref @$[[DIAGNOSEFN:(ss31_diagnoseUnavailableCodeReacheds5NeverOyF|ss31_diagnoseUnavailableCodeReacheds5NeverOyFTwb)]] : $@convention(thin) () -> Never
+// CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+// CHECK:       } // end sil function '$s4Test025unavailableFuncWithNestedC0yyF6nestedL_SiyF'
+
+// CHECK-LABEL: sil{{.*}}@$s4Test033unavailableFuncWithObsoleteNestedC0yyF
+// CHECK:         [[FNREF:%.*]] = function_ref @$[[DIAGNOSEFN:(ss31_diagnoseUnavailableCodeReacheds5NeverOyF|ss31_diagnoseUnavailableCodeReacheds5NeverOyFTwb)]] : $@convention(thin) () -> Never
+// CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+// CHECK:       } // end sil function '$s4Test033unavailableFuncWithObsoleteNestedC0yyF'
+@available(*, unavailable)
+public func unavailableFuncWithObsoleteNestedFunc() {
+  @available(swift, obsoleted: 1)
+  func nested() -> Int { 1 }
+}
+
+// CHECK-LABEL: sil{{.*}}@$s4Test033unavailableFuncWithObsoleteNestedC0yyF6nestedL_SiyF
+// CHECK:         [[FNREF:%.*]] = function_ref @$[[DIAGNOSEFN:(ss31_diagnoseUnavailableCodeReacheds5NeverOyF|ss31_diagnoseUnavailableCodeReacheds5NeverOyFTwb)]] : $@convention(thin) () -> Never
+// CHECK-NEXT:    [[APPLY:%.*]] = apply [[FNREF]]()
+// CHECK:       } // end sil function '$s4Test033unavailableFuncWithObsoleteNestedC0yyF6nestedL_SiyF'
+
 enum SomeError: Error { case generic }
 
 // CHECK-LABEL: sil{{.*}}@$s4Test23unavailableThrowingFuncyyKF