[interop][SwiftToCxx] Add inout support for UnsafePointer/UnsafeMutablePointer param types

Author: hyp

lib/PrintAsClang/PrintClangFunction.cpp

@@ -99,6 +99,10 @@ class CFunctionSignatureTypePrinter
         languageMode(languageMode), modifiersDelegate(modifiersDelegate),
         moduleContext(moduleContext), typeUseKind(typeUseKind) {}
 
+  void printInoutTypeModifier() {
+    os << (languageMode == swift::OutputLanguageMode::Cxx ? " &" : " *");
+  }
+
   bool printIfKnownSimpleType(const TypeDecl *typeDecl,
                               Optional<OptionalTypeKind> optionalKind,
                               bool isInOutParam) {
@@ -109,9 +113,8 @@ class CFunctionSignatureTypePrinter
     if (knownTypeInfo->canBeNullable) {
       printNullability(optionalKind);
     }
-    if (isInOutParam) {
-      os << (languageMode == swift::OutputLanguageMode::Cxx ? " &" : " *");
-    }
+    if (isInOutParam)
+      printInoutTypeModifier();
     return true;
   }
 
@@ -202,6 +205,8 @@ class CFunctionSignatureTypePrinter
       os << " const";
     os << " *";
     printNullability(optionalKind);
+    if (isInOutParam)
+      printInoutTypeModifier();
     return true;
   }
 

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

@@ -8,6 +8,7 @@
 // CHECK: SWIFT_EXTERN void $s9Functions11inOutTwoIntyySiz_SiztF(ptrdiff_t * x, ptrdiff_t * y) SWIFT_NOEXCEPT SWIFT_CALL; // inOutTwoInt(_:_:)
 // CHECK: SWIFT_EXTERN void $s9Functions13inOutTwoParamyySbz_SdztF(bool * x, double * y) SWIFT_NOEXCEPT SWIFT_CALL; // inOutTwoParam(_:_:)
 // CHECK: SWIFT_EXTERN void $s9Functions24inoutTypeWithNullabilityyySVzF(void const * _Nonnull * x) SWIFT_NOEXCEPT SWIFT_CALL; // inoutTypeWithNullability(_:)
+// CHECK: SWIFT_EXTERN void $s9Functions25inoutUnsafeGenericPointeryySPys5Int32VGzF(int32_t const * _Nonnull * x) SWIFT_NOEXCEPT SWIFT_CALL; // inoutUnsafeGenericPointer(_:)
 
 // CHECK:      inline void inOutInt(swift::Int & x) noexcept {
 // CHECK-NEXT:   return _impl::$s9Functions8inOutIntyySizF(&x);
@@ -25,6 +26,9 @@
 // CHECK-NEXT:   return _impl::$s9Functions24inoutTypeWithNullabilityyySVzF(&x);
 // CHECK-NEXT: }
 
+// CHECK:      inline void inoutUnsafeGenericPointer(int32_t const * _Nonnull & x) noexcept {
+// CHECK-NEXT:   return _impl::$s9Functions25inoutUnsafeGenericPointeryySPys5Int32VGzF(&x);
+// CHECK-NEXT: }
 
 public func inOutInt(_ x: inout Int) { x = Int() }
 
@@ -41,3 +45,7 @@ public func inOutTwoParam(_ x: inout Bool, _ y: inout Double) {
 public func inoutTypeWithNullability(_ x: inout UnsafeRawPointer) {
     x += 1
 }
+
+public func inoutUnsafeGenericPointer(_ x: inout UnsafePointer<Int32>) {
+    x += 1
+}

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

@@ -47,4 +47,13 @@ int main() {
         inoutTypeWithNullability(p);
         assert(*static_cast<const char *>(p) == 'B');
     }
+
+    {
+        int a[2] = {1,2};
+        const int *p = a;
+        assert(*p == 1);
+        inoutUnsafeGenericPointer(p);
+        assert(p == &a[1]);
+        assert(*p == 2);
+    }
 }