[Runtime] Fix generic existentials in layout strings

Author: drexin

stdlib/public/runtime/Metadata.cpp

@@ -2895,7 +2895,7 @@ void swift::_swift_addRefCountStringForMetatype(LayoutStringWriter &writer,
     auto tag = existential->isClassBounded() ? RefCountingKind::Unknown
                                              : RefCountingKind::Existential;
     writer.writeBytes(((uint64_t)tag << 56) | offset);
-    previousFieldOffset = existential->isClassBounded() ? fieldType->vw_size() - sizeof(uintptr_t) : 0;
+    previousFieldOffset = fieldType->vw_size() - (existential->isClassBounded() ? sizeof(uintptr_t) : (NumWords_ValueBuffer * sizeof(uintptr_t)));
     fullOffset += fieldType->vw_size();
   } else {
 metadata:

test/Interpreter/Inputs/layout_string_witnesses_types.swift

@@ -279,6 +279,17 @@ public struct MultiProtocolExistentialWrapper {
     }
 }
 
+public struct AnyWrapper {
+    let x: Int = 0
+    let y: Any
+    let z: AnyObject
+
+    public init(y: Any, z: AnyObject) {
+        self.y = y
+        self.z = z
+    }
+}
+
 #if os(macOS)
 import Foundation
 
@@ -343,8 +354,8 @@ public struct NestedWrapper<T> {
 }
 
 struct InternalGeneric<T> {
-    let x: T
     let y: Int
+    let x: T
 }
 
 public enum SinglePayloadSimpleClassEnum {
@@ -615,19 +626,19 @@ public func allocateInternalGenericPtr<T>(of tpe: T.Type) -> UnsafeMutableRawPoi
 @inline(never)
 public func testGenericAssign<T>(_ ptr: __owned UnsafeMutableRawPointer, from x: T) {
     let ptr = ptr.assumingMemoryBound(to: InternalGeneric<T>.self)
-    let x = InternalGeneric(x: x, y: 23)
+    let x = InternalGeneric(y: 23, x: x)
     testAssign(ptr, from: x)
 }
 
 @inline(never)
 public func testGenericInit<T>(_ ptr: __owned UnsafeMutableRawPointer, to x: T) {
     let ptr = ptr.assumingMemoryBound(to: InternalGeneric<T>.self)
-    let x = InternalGeneric(x: x, y: 23)
+    let x = InternalGeneric(y: 23, x: x)
     testInit(ptr, to: x)
 }
 
 @inline(never)
 public func testGenericDestroy<T>(_ ptr: __owned UnsafeMutableRawPointer, of tpe: T.Type) {
-    let ptr = ptr.assumingMemoryBound(to: tpe)
+    let ptr = ptr.assumingMemoryBound(to: InternalGeneric<T>.self)
     testDestroy(ptr)
 }

test/Interpreter/layout_string_witnesses_dynamic.swift

@@ -4,7 +4,7 @@
 // RUN: %target-codesign %t/%target-library-name(layout_string_witnesses_types)
 // RUN: %target-swift-frontend -enable-experimental-feature LayoutStringValueWitnesses -enable-experimental-feature LayoutStringValueWitnessesInstantiation -enable-layout-string-value-witnesses -enable-layout-string-value-witnesses-instantiation -enable-library-evolution -enable-autolinking-runtime-compatibility-bytecode-layouts -emit-module -emit-module-path=%t/layout_string_witnesses_types_resilient.swiftmodule %S/Inputs/layout_string_witnesses_types_resilient.swift
 // RUN: %target-build-swift -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnessesInstantiation -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-layout-string-value-witnesses-instantiation -Xfrontend -enable-library-evolution -c -parse-as-library -o %t/layout_string_witnesses_types_resilient.o %S/Inputs/layout_string_witnesses_types_resilient.swift
-// RUN: %target-build-swift -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnessesInstantiation -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-layout-string-value-witnesses-instantiation -Xfrontend -enable-type-layout -parse-stdlib -module-name layout_string_witnesses_dynamic -llayout_string_witnesses_types -L%t %t/layout_string_witnesses_types_resilient.o -I %t -o %t/main %s %target-rpath(%t)
+// RUN: %target-build-swift -g -parse-stdlib -module-name layout_string_witnesses_dynamic -llayout_string_witnesses_types -L%t %t/layout_string_witnesses_types_resilient.o -I %t -o %t/main %s %target-rpath(%t)
 // RUN: %target-codesign %t/main
 // RUN: %target-run %t/main %t/%target-library-name(layout_string_witnesses_types) | %FileCheck %s --check-prefix=CHECK -check-prefix=CHECK-%target-os
 
@@ -92,7 +92,35 @@ func testGeneric() {
 
 testGeneric()
 
-func testPrespecializedStructAnyObject() {
+func testGenericAny() {
+    let ptr = allocateInternalGenericPtr(of: Any.self)
+
+    do {
+        let x: Any = TestClass()
+        testGenericInit(ptr, to: x as Any)
+    }
+
+    do {
+        let y: Any = TestClass()
+        // CHECK: Before deinit
+        print("Before deinit")
+
+        // CHECK-NEXT: TestClass deinitialized!
+        testGenericAssign(ptr, from: y as Any)
+    }
+
+    // CHECK-NEXT: Before deinit
+    print("Before deinit")
+
+    // CHECK-NEXT: TestClass deinitialized!
+    testGenericDestroy(ptr, of: Any.self)
+
+    ptr.deallocate()
+}
+
+testGenericAny()
+
+func testPrespecializedAnyObject() {
     let ptr = UnsafeMutablePointer<PrespecializedStruct<AnyObject>>.allocate(capacity: 1)
 
     do {
@@ -120,7 +148,7 @@ func testPrespecializedStructAnyObject() {
     ptr.deallocate()
 }
 
-testPrespecializedStructAnyObject()
+testPrespecializedAnyObject()
 
 func testPrespecializedStructSimpleClass() {
     let ptr = UnsafeMutablePointer<PrespecializedStruct<SimpleClass>>.allocate(capacity: 1)
@@ -866,7 +894,7 @@ func testResilientSinglePayloadEnumComplexTag() {
 testResilientSinglePayloadEnumComplexTag()
 
 func testResilientMultiPayloadEnumTag() {
-    let x = switch getResilientMultiPayloadEnumEmpty0() {
+    let x = switch getResilientMultiPayloadEnumEmpty0(AnyObject.self) {
     case .nonEmpty0: 0
     case .nonEmpty1: 1
     case .empty0: 2

test/Interpreter/layout_string_witnesses_static.swift

@@ -293,6 +293,37 @@ func testExistentialStructBox() {
 
 testExistentialStructBox()
 
+func testAnyWrapper() {
+    let ptr = UnsafeMutablePointer<AnyWrapper>.allocate(capacity: 1)
+
+    do {
+        let x = TestClass()
+        testInit(ptr, to: AnyWrapper(y: x, z: SimpleClass(x: 23)))
+    }
+
+    do {
+        let y = TestClass()
+
+        // CHECK: Before deinit
+        print("Before deinit")
+
+        // CHECK-NEXT: TestClass deinitialized!
+        // CHECK-NEXT: SimpleClass deinitialized!
+        testAssign(ptr, from: AnyWrapper(y: y, z: SimpleClass(x: 32)))
+    }
+
+    // CHECK-NEXT: Before deinit
+    print("Before deinit")
+
+    // CHECK-NEXT: TestClass deinitialized!
+    // CHECK-NEXT: SimpleClass deinitialized!
+    testDestroy(ptr)
+
+    ptr.deallocate()
+}
+
+testAnyWrapper()
+
 class ClassWithABC: A, B, C {
     deinit {
         print("ClassWithABC deinitialized!")