[Windows] Use thiscall as the default calling convention for class methods. PR12785

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160121 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 33 insertions, 14 deletions

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 27e4de926d..2a1521e21e 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -7098,9 +7098,15 @@ bool ASTContext::DeclMustBeEmitted(const Decl *D) {
   return true;
 }
 
-CallingConv ASTContext::getDefaultMethodCallConv() {
+CallingConv ASTContext::getDefaultCXXMethodCallConv(bool isVariadic) {
   // Pass through to the C++ ABI object
-  return ABI->getDefaultMethodCallConv();
+  return ABI->getDefaultMethodCallConv(isVariadic);
+}
+
+CallingConv ASTContext::getCanonicalCallConv(CallingConv CC) const {
+  if (CC == CC_C && !LangOpts.MRTD && getTargetInfo().getCXXABI() != CXXABI_Microsoft)
+    return CC_Default;
+  return CC;
 }
 
 bool ASTContext::isNearlyEmpty(const CXXRecordDecl *RD) const {
diff --git a/lib/AST/CXXABI.h b/lib/AST/CXXABI.h
index 943c43e791..0d9c869d87 100644
--- a/lib/AST/CXXABI.h
+++ b/lib/AST/CXXABI.h
@@ -32,7 +32,7 @@ public:
   virtual unsigned getMemberPointerSize(const MemberPointerType *MPT) const = 0;
 
   /// Returns the default calling convention for C++ methods.
-  virtual CallingConv getDefaultMethodCallConv() const = 0;
+  virtual CallingConv getDefaultMethodCallConv(bool isVariadic) const = 0;
 
   // Returns whether the given class is nearly empty, with just virtual pointers
   // and no data except possibly virtual bases.
diff --git a/lib/AST/ItaniumCXXABI.cpp b/lib/AST/ItaniumCXXABI.cpp
index 0027dbf191..ce1244c542 100644
--- a/lib/AST/ItaniumCXXABI.cpp
+++ b/lib/AST/ItaniumCXXABI.cpp
@@ -39,7 +39,7 @@ public:
     return 1;
   }
 
-  CallingConv getDefaultMethodCallConv() const {
+  CallingConv getDefaultMethodCallConv(bool isVariadic) const {
     return CC_C;
   }
 
diff --git a/lib/AST/MicrosoftCXXABI.cpp b/lib/AST/MicrosoftCXXABI.cpp
index f33d6fe1f5..51308ea0c0 100644
--- a/lib/AST/MicrosoftCXXABI.cpp
+++ b/lib/AST/MicrosoftCXXABI.cpp
@@ -29,8 +29,8 @@ public:
 
   unsigned getMemberPointerSize(const MemberPointerType *MPT) const;
 
-  CallingConv getDefaultMethodCallConv() const {
-    if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
+  CallingConv getDefaultMethodCallConv(bool isVariadic) const {
+    if (!isVariadic && Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
       return CC_X86ThisCall;
     else
       return CC_C;
diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index 37c654d666..d9fa057971 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -1159,8 +1159,16 @@ void MicrosoftCXXNameMangler::mangleCallingConvention(const FunctionType *T,
   // that they could be in a DLL and somebody from another module could call
   // them.)
   CallingConv CC = T->getCallConv();
-  if (CC == CC_Default)
-    CC = IsInstMethod ? getASTContext().getDefaultMethodCallConv() : CC_C;
+  if (CC == CC_Default) {
+    if (IsInstMethod) {
+      const FunctionProtoType *FPT =
+        T->getCanonicalTypeUnqualified().getAs<FunctionProtoType>();
+      bool isVariadic = FPT->isVariadic();
+      CC = getASTContext().getDefaultCXXMethodCallConv(isVariadic);
+    } else {
+      CC = CC_C;
+    }
+  }
   switch (CC) {
     default:
       llvm_unreachable("Unsupported CC for mangling");
diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 0ecd97693f..37a9a5eaff 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -105,8 +105,12 @@ static const CGFunctionInfo &arrangeFreeFunctionType(CodeGenTypes &CGT,
 /// Given the formal ext-info of a C++ instance method, adjust it
 /// according to the C++ ABI in effect.
 static void adjustCXXMethodInfo(CodeGenTypes &CGT,
-                                FunctionType::ExtInfo &extInfo) {
-  // FIXME: thiscall on Microsoft
+                                FunctionType::ExtInfo &extInfo,
+                                bool isVariadic) {
+  if (extInfo.getCC() == CC_Default) {
+    CallingConv CC = CGT.getContext().getDefaultCXXMethodCallConv(isVariadic);
+    extInfo = extInfo.withCallingConv(CC);
+  }
 }
 
 /// Arrange the argument and result information for a free function (i.e.
@@ -115,7 +119,7 @@ static const CGFunctionInfo &arrangeCXXMethodType(CodeGenTypes &CGT,
                                       SmallVectorImpl<CanQualType> &prefix,
                                             CanQual<FunctionProtoType> FTP) {
   FunctionType::ExtInfo extInfo = FTP->getExtInfo();
-  adjustCXXMethodInfo(CGT, extInfo);
+  adjustCXXMethodInfo(CGT, extInfo, FTP->isVariadic());
   return arrangeLLVMFunctionInfo(CGT, prefix, FTP, extInfo);
 }
 
@@ -202,7 +206,7 @@ CodeGenTypes::arrangeCXXConstructorDeclaration(const CXXConstructorDecl *D,
     argTypes.push_back(FTP->getArgType(i));
 
   FunctionType::ExtInfo extInfo = FTP->getExtInfo();
-  adjustCXXMethodInfo(*this, extInfo);
+  adjustCXXMethodInfo(*this, extInfo, FTP->isVariadic());
   return arrangeLLVMFunctionInfo(resultType, argTypes, extInfo, required);
 }
 
@@ -220,9 +224,10 @@ CodeGenTypes::arrangeCXXDestructor(const CXXDestructorDecl *D,
 
   CanQual<FunctionProtoType> FTP = GetFormalType(D);
   assert(FTP->getNumArgs() == 0 && "dtor with formal parameters");
+  assert(FTP->isVariadic() == 0 && "dtor with formal parameters");
 
   FunctionType::ExtInfo extInfo = FTP->getExtInfo();
-  adjustCXXMethodInfo(*this, extInfo);
+  adjustCXXMethodInfo(*this, extInfo, false);
   return arrangeLLVMFunctionInfo(resultType, argTypes, extInfo,
                                  RequiredArgs::All);
 }
@@ -354,7 +359,7 @@ CodeGenTypes::arrangeCXXMethodCall(const CallArgList &args,
     argTypes.push_back(Context.getCanonicalParamType(i->Ty));
 
   FunctionType::ExtInfo info = FPT->getExtInfo();
-  adjustCXXMethodInfo(*this, info);
+  adjustCXXMethodInfo(*this, info, FPT->isVariadic());
   return arrangeLLVMFunctionInfo(GetReturnType(FPT->getResultType()),
                                  argTypes, info, required);
 }