1 files changed, 30 insertions, 23 deletions

diff --git a/clang/lib/CodeGen/MicrosoftCXXABI.cpp b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
index 08302f35d5d..2bb37834f53 100644
--- a/clang/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -206,8 +206,9 @@ public:
   // lacks a definition for the destructor, non-base destructors must always
   // delegate to or alias the base destructor.
 
-  void buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
-                              SmallVectorImpl<CanQualType> &ArgTys) override;
+  AddedStructorArgs
+  buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
+                         SmallVectorImpl<CanQualType> &ArgTys) override;
 
   /// Non-base dtors should be emitted as delegating thunks in this ABI.
   bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
@@ -248,11 +249,10 @@ public:
 
   void EmitInstanceFunctionProlog(CodeGenFunction &CGF) override;
 
-  unsigned addImplicitConstructorArgs(CodeGenFunction &CGF,
-                                      const CXXConstructorDecl *D,
-                                      CXXCtorType Type, bool ForVirtualBase,
-                                      bool Delegating,
-                                      CallArgList &Args) override;
+  AddedStructorArgs
+  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
+                             CXXCtorType Type, bool ForVirtualBase,
+                             bool Delegating, CallArgList &Args) override;
 
   void EmitDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *DD,
                           CXXDtorType Type, bool ForVirtualBase,
@@ -1261,17 +1261,19 @@ void MicrosoftCXXABI::EmitVBPtrStores(CodeGenFunction &CGF,
   }
 }
 
-void
+CGCXXABI::AddedStructorArgs
 MicrosoftCXXABI::buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
                                         SmallVectorImpl<CanQualType> &ArgTys) {
+  AddedStructorArgs Added;
   // TODO: 'for base' flag
   if (T == StructorType::Deleting) {
     // The scalar deleting destructor takes an implicit int parameter.
     ArgTys.push_back(getContext().IntTy);
+    ++Added.Suffix;
   }
   auto *CD = dyn_cast<CXXConstructorDecl>(MD);
   if (!CD)
-    return;
+    return Added;
 
   // All parameters are already in place except is_most_derived, which goes
   // after 'this' if it's variadic and last if it's not.
@@ -1279,11 +1281,16 @@ MicrosoftCXXABI::buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
   const CXXRecordDecl *Class = CD->getParent();
   const FunctionProtoType *FPT = CD->getType()->castAs<FunctionProtoType>();
   if (Class->getNumVBases()) {
-    if (FPT->isVariadic())
+    if (FPT->isVariadic()) {
       ArgTys.insert(ArgTys.begin() + 1, getContext().IntTy);
-    else
+      ++Added.Prefix;
+    } else {
       ArgTys.push_back(getContext().IntTy);
+      ++Added.Suffix;
+    }
   }
+
+  return Added;
 }
 
 void MicrosoftCXXABI::EmitCXXDestructors(const CXXDestructorDecl *D) {
@@ -1493,14 +1500,14 @@ void MicrosoftCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
   }
 }
 
-unsigned MicrosoftCXXABI::addImplicitConstructorArgs(
+CGCXXABI::AddedStructorArgs MicrosoftCXXABI::addImplicitConstructorArgs(
     CodeGenFunction &CGF, const CXXConstructorDecl *D, CXXCtorType Type,
     bool ForVirtualBase, bool Delegating, CallArgList &Args) {
   assert(Type == Ctor_Complete || Type == Ctor_Base);
 
   // Check if we need a 'most_derived' parameter.
   if (!D->getParent()->getNumVBases())
-    return 0;
+    return AddedStructorArgs{};
 
   // Add the 'most_derived' argument second if we are variadic or last if not.
   const FunctionProtoType *FPT = D->getType()->castAs<FunctionProtoType>();
@@ -1511,13 +1518,13 @@ unsigned MicrosoftCXXABI::addImplicitConstructorArgs(
     MostDerivedArg = llvm::ConstantInt::get(CGM.Int32Ty, Type == Ctor_Complete);
   }
   RValue RV = RValue::get(MostDerivedArg);
-  if (FPT->isVariadic())
+  if (FPT->isVariadic()) {
     Args.insert(Args.begin() + 1,
                 CallArg(RV, getContext().IntTy, /*needscopy=*/false));
-  else
-    Args.add(RV, getContext().IntTy);
-
-  return 1;  // Added one arg.
+    return AddedStructorArgs::prefix(1);
+  }
+  Args.add(RV, getContext().IntTy);
+  return AddedStructorArgs::suffix(1);
 }
 
 void MicrosoftCXXABI::EmitDestructorCall(CodeGenFunction &CGF,
@@ -3918,16 +3925,16 @@ MicrosoftCXXABI::getAddrOfCXXCtorClosure(const CXXConstructorDecl *CD,
   CGF.EmitCallArgs(Args, FPT, llvm::makeArrayRef(ArgVec), CD, IsCopy ? 1 : 0);
 
   // Insert any ABI-specific implicit constructor arguments.
-  unsigned ExtraArgs = addImplicitConstructorArgs(CGF, CD, Ctor_Complete,
-                                                  /*ForVirtualBase=*/false,
-                                                  /*Delegating=*/false, Args);
-
+  AddedStructorArgs ExtraArgs =
+      addImplicitConstructorArgs(CGF, CD, Ctor_Complete,
+                                 /*ForVirtualBase=*/false,
+                                 /*Delegating=*/false, Args);
   // Call the destructor with our arguments.
   llvm::Constant *CalleePtr =
     CGM.getAddrOfCXXStructor(CD, StructorType::Complete);
   CGCallee Callee = CGCallee::forDirect(CalleePtr, CD);
   const CGFunctionInfo &CalleeInfo = CGM.getTypes().arrangeCXXConstructorCall(
-      Args, CD, Ctor_Complete, ExtraArgs);
+      Args, CD, Ctor_Complete, ExtraArgs.Prefix + ExtraArgs.Suffix);
   CGF.EmitCall(CalleeInfo, Callee, ReturnValueSlot(), Args);
 
   Cleanups.ForceCleanup();