[interop][SwiftToCxx] pass and return UnsafePointer/UnsafeMutablePointer types

Author: hyp

lib/PrintAsClang/PrintClangFunction.cpp

@@ -42,6 +42,12 @@ getKnownTypeInfo(const TypeDecl *typeDecl, PrimitiveTypeMapping &typeMapping,
 bool isKnownType(Type t, PrimitiveTypeMapping &typeMapping,
                  OutputLanguageMode languageMode) {
   const TypeDecl *typeDecl;
+  if (auto *bgt = dyn_cast<BoundGenericStructType>(
+          t->isOptional() ? t->getOptionalObjectType()->getDesugaredType()
+                          : t->getDesugaredType())) {
+    return bgt->isUnsafePointer() || bgt->isUnsafeMutablePointer();
+  }
+
   if (auto *typeAliasType = dyn_cast<TypeAliasType>(t.getPointer()))
     typeDecl = typeAliasType->getDecl();
   else if (auto *structDecl = t->getStructOrBoundGenericStruct())
@@ -177,6 +183,35 @@ class CFunctionSignatureTypePrinter
           .printValueTypeReturnType(decl, languageMode, moduleContext);
   }
 
+  bool printIfKnownGenericStruct(const BoundGenericStructType *BGT,
+                                 Optional<OptionalTypeKind> optionalKind,
+                                 bool isInOutParam) {
+    auto bgsTy = Type(const_cast<BoundGenericStructType *>(BGT));
+    bool isConst;
+    if (bgsTy->isUnsafePointer())
+      isConst = true;
+    else if (bgsTy->isUnsafeMutablePointer())
+      isConst = false;
+    else
+      return false;
+
+    auto args = BGT->getGenericArgs();
+    assert(args.size() == 1);
+    visitPart(args.front(), OTK_None, /*isInOutParam=*/false);
+    if (isConst)
+      os << " const";
+    os << " *";
+    printNullability(optionalKind);
+    return true;
+  }
+
+  void visitBoundGenericStructType(BoundGenericStructType *BGT,
+                                   Optional<OptionalTypeKind> optionalKind,
+                                   bool isInOutParam) {
+    if (printIfKnownGenericStruct(BGT, optionalKind, isInOutParam))
+      return;
+  }
+
   void visitPart(Type Ty, Optional<OptionalTypeKind> optionalKind,
                  bool isInOutParam) {
     TypeVisitor::visit(Ty, optionalKind, isInOutParam);

test/Interop/SwiftToCxx/functions/swift-primitive-functions-cxx-bridging.swift

@@ -131,6 +131,22 @@
 // CHECK-NEXT:   return _impl::$s9Functions16passThroughUInt8ys0D0VADF(x);
 // CHECK-NEXT: }
 
+// CHECK:      inline int32_t * _Nullable passThroughUnsafeGenericMutableOptionalPointer(int32_t * _Nullable x) noexcept SWIFT_WARN_UNUSED_RESULT {
+// CHECK-NEXT:   return _impl::$s9Functions46passThroughUnsafeGenericMutableOptionalPointerySpys5Int32VGSgAFF(x);
+// CHECK-NEXT: }
+
+// CHECK:      inline int32_t * _Nonnull passThroughUnsafeGenericMutablePointer(int32_t * _Nonnull x) noexcept SWIFT_WARN_UNUSED_RESULT {
+// CHECK-NEXT:   return _impl::$s9Functions38passThroughUnsafeGenericMutablePointerySpys5Int32VGAEF(x);
+// CHECK-NEXT: }
+
+// CHECK:      inline int32_t const * _Nullable passThroughUnsafeGenericOptionalPointer(int32_t const * _Nullable x) noexcept SWIFT_WARN_UNUSED_RESULT {
+// CHECK-NEXT:   return _impl::$s9Functions39passThroughUnsafeGenericOptionalPointerySPys5Int32VGSgAFF(x);
+// CHECK-NEXT: }
+
+// CHECK:      inline int32_t const * _Nonnull passThroughUnsafeGenericPointer(int32_t const * _Nonnull x) noexcept SWIFT_WARN_UNUSED_RESULT {
+// CHECK-NEXT:   return _impl::$s9Functions31passThroughUnsafeGenericPointerySPys5Int32VGAEF(x);
+// CHECK-NEXT: }
+
 // CHECK:      inline void * _Nonnull passThroughUnsafeMutableRawPointer(void * _Nonnull x) noexcept SWIFT_WARN_UNUSED_RESULT {
 // CHECK-NEXT:   return _impl::$s9Functions34passThroughUnsafeMutableRawPointeryS2vF(x);
 // CHECK-NEXT: }
@@ -189,3 +205,19 @@ public func passThroughUnsafeRawPointer(_ x: UnsafeRawPointer) -> UnsafeRawPoint
 public func passThroughUnsafeMutableRawPointer(_ x: UnsafeMutableRawPointer) -> UnsafeMutableRawPointer { return x }
 
 public func roundTwoPassThroughUnsafeMutableRawPointer(_ x: UnsafeMutableRawPointer?) -> UnsafeMutableRawPointer? { return x }
+
+public func passThroughUnsafeGenericPointer(_ x: UnsafePointer<Int32>) -> UnsafePointer<Int32> {
+    return x
+}
+
+public func passThroughUnsafeGenericOptionalPointer(_ x: UnsafePointer<Int32>?) -> UnsafePointer<Int32>? {
+    return x
+}
+
+public func passThroughUnsafeGenericMutablePointer(_ x: UnsafeMutablePointer<Int32>) -> UnsafeMutablePointer<Int32> {
+    return x
+}
+
+public func passThroughUnsafeGenericMutableOptionalPointer(_ x: UnsafeMutablePointer<Int32>?) -> UnsafeMutablePointer<Int32>? {
+    return x
+}

test/Interop/SwiftToCxx/functions/swift-primitive-functions-execution.cpp

@@ -63,4 +63,13 @@ int main() {
   VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeRawPointer, &x);
   VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeMutableRawPointer, &x);
   VERIFY_PASSTHROUGH_VALUE(roundTwoPassThroughUnsafeMutableRawPointer, nullptr);
+
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericMutableOptionalPointer, &x);
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericMutableOptionalPointer,
+                           nullptr);
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericMutablePointer, &x);
+  const int y = 0;
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericOptionalPointer, &x);
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericOptionalPointer, nullptr);
+  VERIFY_PASSTHROUGH_VALUE(passThroughUnsafeGenericPointer, &x);
 }