From f203dbfba9044987ea4af679ab697c1378c4fdaf Mon Sep 17 00:00:00 2001 From: George Burgess IV Date: Wed, 22 Feb 2017 20:28:02 +0000 Subject: [CodeGen] Note where we add ABI-specific args in ctors. NFC. Meta: The ultimate goal is to teach ExtParameterInfo about pass_object_size attributes. This is necessary for that, since our ExtParameterInfo is a bit buggy in C++. I plan to actually make use of this Prefix/Suffix info in the near future, but I like small single-purpose changes. Especially when those changes are hard to actually test... At the moment, some of our C++-specific CodeGen pretends that ABIs can only add arguments to the beginning of a function call. This isn't quite correct: args can be appended to the end, as well. It hasn't mattered much until now, since we seem to only use this "number of arguments added" data when calculating the ExtParameterInfo to use when making a CGFunctionInfo. Said ExtParameterInfo is currently only used for ParameterABIs (Swift) and ns_consumed (ObjC). So, this patch allows ABIs to indicate whether args they added were at the beginning or end of an argument list. We can use this information to emit ExtParameterInfos more correctly, though like said, that bit is coming soon. No tests since this is theoretically a nop. llvm-svn: 295870 --- clang/lib/CodeGen/MicrosoftCXXABI.cpp | 53 ++++++++++++++++++++--------------- 1 file changed, 30 insertions(+), 23 deletions(-) (limited to 'clang/lib/CodeGen/MicrosoftCXXABI.cpp') 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 &ArgTys) override; + AddedStructorArgs + buildStructorSignature(const CXXMethodDecl *MD, StructorType T, + SmallVectorImpl &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 &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(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(); 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(); @@ -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(); -- cgit v1.2.3