[interop][SwiftToCxx] fix copy constructor for resilient structs

Author: hyp

lib/PrintAsClang/PrintClangValueType.cpp

@@ -140,6 +140,11 @@ void ClangValueTypePrinter::printValueTypeDecl(
   os << "    auto *vwTable = ";
   printer.printValueWitnessTableAccessFromTypeMetadata("metadata");
   os << ";\n";
+  if (isOpaqueLayout) {
+    os << "    _storage = ";
+    printer.printSwiftImplQualifier();
+    os << cxx_synthesis::getCxxOpaqueStorageClassName() << "(vwTable);\n";
+  }
   os << "    vwTable->initializeWithCopy(_getOpaquePointer(), const_cast<char "
         "*>(other._getOpaquePointer()), metadata._0);\n";
   os << "  }\n";

lib/PrintAsClang/PrintSwiftToClangCoreScaffold.cpp

@@ -132,6 +132,10 @@ static void printSwiftResilientStorageClass(raw_ostream &os) {
      << "&& other) : storage(other.storage) { other.storage = nullptr; }\n";
   os << "  inline " << name << "(const " << name << "&) = delete;\n";
   os << "  inline ~" << name << "() { if (storage) { delete[] storage; } }\n";
+  os << "  void operator =(" << name
+     << "&& other) { auto temp = storage; storage = other.storage; "
+        "other.storage = temp; }\n";
+  os << "  void operator =(const " << name << "&) = delete;\n";
   os << "  inline char * _Nonnull getOpaquePointer() { return static_cast<char "
         "* _Nonnull>(storage); }\n";
   os << "  inline const char * _Nonnull getOpaquePointer() const { return "

test/Interop/SwiftToCxx/core/swift-impl-defs-in-cxx.swift

@@ -59,6 +59,8 @@
 // CHECK-NEXT:   inline OpaqueStorage(OpaqueStorage&& other) : storage(other.storage) { other.storage = nullptr; }
 // CHECK-NEXT:   inline OpaqueStorage(const OpaqueStorage&) = delete;
 // CHECK-NEXT:   inline ~OpaqueStorage() { if (storage) { delete[] storage; } }
+// CHECK-NEXT:   void operator =(OpaqueStorage&& other) { auto temp = storage; storage = other.storage; other.storage = temp; }
+// CHECK-NEXT:   void operator =(const OpaqueStorage&) = delete;
 // CHECK-NEXT:   inline char * _Nonnull getOpaquePointer() { return static_cast<char * _Nonnull>(storage); }
 // CHECK-NEXT:   inline const char * _Nonnull getOpaquePointer() const { return static_cast<char * _Nonnull>(storage); }
 // CHECK-NEXT: private:

test/Interop/SwiftToCxx/structs/resilient-struct-in-cxx-execution.cpp

@@ -34,6 +34,13 @@ int main() {
 // CURRENT-NEXT: x = 65
 // CHANGE-NEXT: x&y = 65&0
 
+  auto copySmallStruct = smallStruct;
+  mutateSmall(copySmallStruct);
+  copySmallStruct.dump();
+// CHECK: find - small dump
+// CURRENT-NEXT: x = 66
+// CHANGE-NEXT: x&y = 0&65
+
   printSmallAndLarge(smallStruct, largeStruct);
 // CHECK: find - small dump
 // CURRENT-NEXT: x = 65
@@ -44,9 +51,14 @@ int main() {
     auto structWithRefCountStoredProp =
       createStructWithRefCountStoredProp();
     structWithRefCountStoredProp.dump();
+    {
+       StructWithRefCountStoredProp copy(structWithRefCountStoredProp);
+    }
+    structWithRefCountStoredProp.dump();
   }
 // CHECK-NEXT: create RefCountedClass 0
 // CHECK-NEXT: storedRef = 0
+// CHECK-NEXT: storedRef = 0
 // CHECK-NEXT: destroy RefCountedClass 0
   return 0;
 }

test/Interop/SwiftToCxx/structs/resilient-struct-in-cxx.swift

@@ -5,9 +5,9 @@
 // RUN: %check-interop-cxx-header-in-clang(%t/structs.h)
 
 public struct FirstSmallStruct {
-    public let x: UInt32
+    public var x: UInt32
 #if CHANGE_LAYOUT
-    public let y: UInt32 = 0
+    public var y: UInt32 = 0
 #endif
 
     public func dump() {
@@ -22,6 +22,12 @@ public struct FirstSmallStruct {
 
 // CHECK: class FirstSmallStruct final {
 // CHECK-NEXT: public:
+// CHECK: inline FirstSmallStruct(const FirstSmallStruct &other) {
+// CHECK-NEXT:   auto metadata = _impl::$s7Structs16FirstSmallStructVMa(0);
+// CHECK-NEXT:   auto *vwTable = *(reinterpret_cast<swift::_impl::ValueWitnessTable **>(metadata._0) - 1);
+// CHECK-NEXT:   _storage = swift::_impl::OpaqueStorage(vwTable);
+// CHECK-NEXT:   vwTable->initializeWithCopy(_getOpaquePointer(), const_cast<char *>(other._getOpaquePointer()), metadata._0);
+// CHECK-NEXT: }
 // CHECK: private:
 // CHECK-NEXT:  inline FirstSmallStruct(swift::_impl::ValueWitnessTable *vwTable) : _storage(vwTable) {}
 // CHECK-NEXT:  static inline FirstSmallStruct _make() {
@@ -57,6 +63,12 @@ public struct LargeStruct {
 
 // CHECK: class LargeStruct final {
 // CHECK-NEXT: public:
+// CHECK: inline LargeStruct(const LargeStruct &other) {
+// CHECK-NEXT:   auto metadata = _impl::$s7Structs11LargeStructVMa(0);
+// CHECK-NEXT:   auto *vwTable = *(reinterpret_cast<swift::_impl::ValueWitnessTable **>(metadata._0) - 1);
+// CHECK-NEXT:   _storage = swift::_impl::OpaqueStorage(vwTable);
+// CHECK-NEXT:   vwTable->initializeWithCopy(_getOpaquePointer(), const_cast<char *>(other._getOpaquePointer()), metadata._0);
+// CHECK-NEXT: }
 // CHECK: private:
 // CHECK-NEXT:  inline LargeStruct(swift::_impl::ValueWitnessTable *vwTable) : _storage(vwTable) {}
 // CHECK-NEXT:  static inline LargeStruct _make() {
@@ -124,6 +136,16 @@ public func createStructWithRefCountStoredProp() -> StructWithRefCountStoredProp
     return StructWithRefCountStoredProp(x: 0)
 }
 
+public func mutateSmall(_ x: inout FirstSmallStruct) {
+#if CHANGE_LAYOUT
+    let y = x.y
+    x.y = x.x
+    x.x = y
+#else
+    x.x += 1
+#endif
+}
+
 // CHECK:      inline LargeStruct createLargeStruct(swift::Int x) noexcept SWIFT_WARN_UNUSED_RESULT {
 // CHECK-NEXT:   return _impl::_impl_LargeStruct::returnNewValue([&](void * _Nonnull result) {
 // CHECK-NEXT:     _impl::$s7Structs17createLargeStructyAA0cD0VSiF(result, x);
@@ -136,6 +158,10 @@ public func createStructWithRefCountStoredProp() -> StructWithRefCountStoredProp
 // CHECK-NEXT:   });
 // CHECK-NEXT: }
 
+// CHECK:      inline void mutateSmall(FirstSmallStruct& x) noexcept {
+// CHECK-NEXT:   return _impl::$s7Structs11mutateSmallyyAA05FirstC6StructVzF(_impl::_impl_FirstSmallStruct::getOpaquePointer(x));
+// CHECK-NEXT: }
+
 // CHECK:      inline void printSmallAndLarge(const FirstSmallStruct& x, const LargeStruct& y) noexcept {
 // CHECK-NEXT:   return _impl::$s7Structs18printSmallAndLargeyyAA05FirstC6StructV_AA0eG0VtF(_impl::_impl_FirstSmallStruct::getOpaquePointer(x), _impl::_impl_LargeStruct::getOpaquePointer(y));
 // CHECK-NEXT: }