3 files changed, 20 insertions, 62 deletions

diff --git a/clang/lib/CodeGen/CGClass.cpp b/clang/lib/CodeGen/CGClass.cpp
index ed44679a886..7e94af391f9 100644
--- a/clang/lib/CodeGen/CGClass.cpp
+++ b/clang/lib/CodeGen/CGClass.cpp
@@ -1725,26 +1725,15 @@ void CodeGenFunction::EmitLambdaToBlockPointerBody(FunctionArgList &Args) {
   CGM.ErrorUnsupported(CurFuncDecl, "lambda conversion to block");
 }
 
-void CodeGenFunction::EmitLambdaThunkBody(llvm::Function *Fn,
-                                          const CGFunctionInfo &FnInfo,
-                                          const CXXRecordDecl *Lambda) {
+void CodeGenFunction::EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD) {
+  const CXXRecordDecl *Lambda = MD->getParent();
   DeclarationName Name
     = getContext().DeclarationNames.getCXXOperatorName(OO_Call);
   DeclContext::lookup_const_result Calls = Lambda->lookup(Name);
-  CXXMethodDecl *MD = cast<CXXMethodDecl>(*Calls.first++);
+  CXXMethodDecl *CallOperator = cast<CXXMethodDecl>(*Calls.first++);
   const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
   QualType ResultType = FPT->getResultType();
 
-  // Begin function
-  FunctionArgList FunctionArgs;
-  for (FunctionDecl::param_const_iterator I = MD->param_begin(),
-       E = MD->param_end(); I != E; ++I) {
-    ParmVarDecl *Param = *I;
-    FunctionArgs.push_back(Param);
-  }
-  StartFunction(GlobalDecl(), ResultType, Fn, FnInfo, FunctionArgs,
-                SourceLocation());
-
   // Start building arguments for forwarding call
   CallArgList CallArgs;
 
@@ -1760,7 +1749,7 @@ void CodeGenFunction::EmitLambdaThunkBody(llvm::Function *Fn,
   }
 
   // Get the address of the call operator.
-  GlobalDecl GD(MD);
+  GlobalDecl GD(CallOperator);
   const CGFunctionInfo &CalleeFnInfo = CGM.getTypes().getFunctionInfo(GD);
   llvm::Type *Ty =
     CGM.getTypes().GetFunctionType(CalleeFnInfo, FPT->isVariadic());
@@ -1769,54 +1758,24 @@ void CodeGenFunction::EmitLambdaThunkBody(llvm::Function *Fn,
   // Determine whether we have a return value slot to use.
   ReturnValueSlot Slot;
   if (!ResultType->isVoidType() &&
-      FnInfo.getReturnInfo().getKind() == ABIArgInfo::Indirect &&
+      CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect &&
       hasAggregateLLVMType(CurFnInfo->getReturnType()))
     Slot = ReturnValueSlot(ReturnValue, ResultType.isVolatileQualified());
   
   // Now emit our call.
-  RValue RV = EmitCall(CalleeFnInfo, Callee, Slot, CallArgs, MD);
+  RValue RV = EmitCall(CalleeFnInfo, Callee, Slot, CallArgs, CallOperator);
 
   // Forward the returned value
   if (!ResultType->isVoidType() && Slot.isNull())
     EmitReturnOfRValue(RV, ResultType);
-
-  // End the function.
-  FinishFunction();
 }
 
-llvm::Constant *
-CodeGenFunction::EmitLambdaConvertedFnPtr(const CXXMethodDecl *MD) {
-  QualType FnTy = MD->getResultType()->getPointeeType();
-  CanQual<FunctionProtoType> CanFnTy =
-      CGM.getContext().getCanonicalType(FnTy)->getAs<FunctionProtoType>();
-  llvm::FunctionType *FnLLVMTy = cast<llvm::FunctionType>(CGM.getTypes().ConvertType(FnTy));
-  const CXXRecordDecl *Lambda = MD->getParent();
-  const CGFunctionInfo &FnInfo = CGM.getTypes().getFunctionInfo(CanFnTy);
-
-  if (CanFnTy->isVariadic()) {
+void CodeGenFunction::EmitLambdaStaticInvokeFunction(const CXXMethodDecl *MD) {
+  if (MD->isVariadic()) {
     // FIXME: Making this work correctly is nasty because it requires either
     // cloning the body of the call operator or making the call operator forward.
     CGM.ErrorUnsupported(MD, "lambda conversion to variadic function");
-    return llvm::UndefValue::get(FnLLVMTy->getPointerTo());
   }
 
-  // Build a declaration for the function which this function will
-  // return a pointer to.
-  // FIXME: Should the "thunk" actually be part of the AST?  That would allow
-  // the conversion to function pointer to be constexpr...
-  std::string MangledName =
-      (llvm::Twine(CurFn->getName()) + "_lambdacallthunk").str();
-  llvm::Function *Fn =
-      llvm::Function::Create(FnLLVMTy, llvm::Function::InternalLinkage,
-                            MangledName, &CGM.getModule());
-
-  // Emit the definition of the new function.
-  CodeGenFunction(CGM).EmitLambdaThunkBody(Fn, FnInfo, Lambda);
-  return Fn;
-}
-
-void CodeGenFunction::EmitLambdaToFunctionPointerBody(FunctionArgList &Args) {
-  const CXXMethodDecl *MD = cast<CXXMethodDecl>(CurFuncDecl);
-  EmitReturnOfRValue(RValue::get(EmitLambdaConvertedFnPtr(MD)),
-                     MD->getResultType());
+  EmitLambdaDelegatingInvokeBody(MD);
 }
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 1034de736c1..28c5935de04 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -448,13 +448,15 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
            FD->hasAttr<CUDAGlobalAttr>())
     CGM.getCUDARuntime().EmitDeviceStubBody(*this, Args);
   else if (isa<CXXConversionDecl>(FD) &&
-           cast<CXXConversionDecl>(FD)->getParent()->isLambda()) {
-    // The lambda conversion operators are special; the semantics can't be
-    // expressed in the AST, so IRGen needs to special-case them.
-    if (cast<CXXConversionDecl>(FD)->isLambdaToBlockPointerConversion())
-      EmitLambdaToBlockPointerBody(Args);
-    else
-      EmitLambdaToFunctionPointerBody(Args);
+           cast<CXXConversionDecl>(FD)->isLambdaToBlockPointerConversion()) {
+    // The lambda conversion to block pointer is special; the semantics can't be
+    // expressed in the AST, so IRGen needs to special-case it.
+    EmitLambdaToBlockPointerBody(Args);
+  } else if (isa<CXXMethodDecl>(FD) &&
+             cast<CXXMethodDecl>(FD)->isLambdaStaticInvoker()) {
+    // The lambda "__invoke" function is special, because it forwards or
+    // clones the body of the function call operator (but is actually static).
+    EmitLambdaStaticInvokeFunction(cast<CXXMethodDecl>(FD));
   }
   else
     EmitFunctionBody(Args);
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 2b9b8ab7b88..427ee08e69e 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1377,11 +1377,8 @@ public:
   void EmitFunctionBody(FunctionArgList &Args);
 
   void EmitLambdaToBlockPointerBody(FunctionArgList &Args);
-  void EmitLambdaToFunctionPointerBody(FunctionArgList &Args);
-  llvm::Constant *EmitLambdaConvertedFnPtr(const CXXMethodDecl *MD);
-  void EmitLambdaThunkBody(llvm::Function *Fn,
-                           const CGFunctionInfo &FnInfo,
-                           const CXXRecordDecl *Lambda);
+  void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
+  void EmitLambdaStaticInvokeFunction(const CXXMethodDecl *MD);
 
   /// EmitReturnBlock - Emit the unified return block, trying to avoid its
   /// emission when possible.