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Diffstat (limited to 'clang/lib/CodeGen/CGCall.cpp')
| -rw-r--r-- | clang/lib/CodeGen/CGCall.cpp | 4611 |
1 files changed, 4611 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp new file mode 100644 index 0000000000000..b74f6f942426e --- /dev/null +++ b/clang/lib/CodeGen/CGCall.cpp @@ -0,0 +1,4611 @@ +//===--- CGCall.cpp - Encapsulate calling convention details --------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// These classes wrap the information about a call or function +// definition used to handle ABI compliancy. +// +//===----------------------------------------------------------------------===// + +#include "CGCall.h" +#include "ABIInfo.h" +#include "CGBlocks.h" +#include "CGCXXABI.h" +#include "CGCleanup.h" +#include "CodeGenFunction.h" +#include "CodeGenModule.h" +#include "TargetInfo.h" +#include "clang/AST/Decl.h" +#include "clang/AST/DeclCXX.h" +#include "clang/AST/DeclObjC.h" +#include "clang/Basic/CodeGenOptions.h" +#include "clang/Basic/TargetBuiltins.h" +#include "clang/Basic/TargetInfo.h" +#include "clang/CodeGen/CGFunctionInfo.h" +#include "clang/CodeGen/SwiftCallingConv.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/Transforms/Utils/Local.h" +#include "llvm/Analysis/ValueTracking.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/CallingConv.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/InlineAsm.h" +#include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/Intrinsics.h" +using namespace clang; +using namespace CodeGen; + +/***/ + +unsigned CodeGenTypes::ClangCallConvToLLVMCallConv(CallingConv CC) { + switch (CC) { + default: return llvm::CallingConv::C; + case CC_X86StdCall: return llvm::CallingConv::X86_StdCall; + case CC_X86FastCall: return llvm::CallingConv::X86_FastCall; + case CC_X86RegCall: return llvm::CallingConv::X86_RegCall; + case CC_X86ThisCall: return llvm::CallingConv::X86_ThisCall; + case CC_Win64: return llvm::CallingConv::Win64; + case CC_X86_64SysV: return llvm::CallingConv::X86_64_SysV; + case CC_AAPCS: return llvm::CallingConv::ARM_AAPCS; + case CC_AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP; + case CC_IntelOclBicc: return llvm::CallingConv::Intel_OCL_BI; + // TODO: Add support for __pascal to LLVM. + case CC_X86Pascal: return llvm::CallingConv::C; + // TODO: Add support for __vectorcall to LLVM. + case CC_X86VectorCall: return llvm::CallingConv::X86_VectorCall; + case CC_AArch64VectorCall: return llvm::CallingConv::AArch64_VectorCall; + case CC_SpirFunction: return llvm::CallingConv::SPIR_FUNC; + case CC_OpenCLKernel: return CGM.getTargetCodeGenInfo().getOpenCLKernelCallingConv(); + case CC_PreserveMost: return llvm::CallingConv::PreserveMost; + case CC_PreserveAll: return llvm::CallingConv::PreserveAll; + case CC_Swift: return llvm::CallingConv::Swift; + } +} + +/// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR +/// qualification. Either or both of RD and MD may be null. A null RD indicates +/// that there is no meaningful 'this' type, and a null MD can occur when +/// calling a method pointer. +CanQualType CodeGenTypes::DeriveThisType(const CXXRecordDecl *RD, + const CXXMethodDecl *MD) { + QualType RecTy; + if (RD) + RecTy = Context.getTagDeclType(RD)->getCanonicalTypeInternal(); + else + RecTy = Context.VoidTy; + + if (MD) + RecTy = Context.getAddrSpaceQualType(RecTy, MD->getMethodQualifiers().getAddressSpace()); + return Context.getPointerType(CanQualType::CreateUnsafe(RecTy)); +} + +/// Returns the canonical formal type of the given C++ method. +static CanQual<FunctionProtoType> GetFormalType(const CXXMethodDecl *MD) { + return MD->getType()->getCanonicalTypeUnqualified() + .getAs<FunctionProtoType>(); +} + +/// Returns the "extra-canonicalized" return type, which discards +/// qualifiers on the return type. Codegen doesn't care about them, +/// and it makes ABI code a little easier to be able to assume that +/// all parameter and return types are top-level unqualified. +static CanQualType GetReturnType(QualType RetTy) { + return RetTy->getCanonicalTypeUnqualified().getUnqualifiedType(); +} + +/// Arrange the argument and result information for a value of the given +/// unprototyped freestanding function type. +const CGFunctionInfo & +CodeGenTypes::arrangeFreeFunctionType(CanQual<FunctionNoProtoType> FTNP) { + // When translating an unprototyped function type, always use a + // variadic type. + return arrangeLLVMFunctionInfo(FTNP->getReturnType().getUnqualifiedType(), + /*instanceMethod=*/false, + /*chainCall=*/false, None, + FTNP->getExtInfo(), {}, RequiredArgs(0)); +} + +static void addExtParameterInfosForCall( + llvm::SmallVectorImpl<FunctionProtoType::ExtParameterInfo> ¶mInfos, + const FunctionProtoType *proto, + unsigned prefixArgs, + unsigned totalArgs) { + assert(proto->hasExtParameterInfos()); + assert(paramInfos.size() <= prefixArgs); + assert(proto->getNumParams() + prefixArgs <= totalArgs); + + paramInfos.reserve(totalArgs); + + // Add default infos for any prefix args that don't already have infos. + paramInfos.resize(prefixArgs); + + // Add infos for the prototype. + for (const auto &ParamInfo : proto->getExtParameterInfos()) { + paramInfos.push_back(ParamInfo); + // pass_object_size params have no parameter info. + if (ParamInfo.hasPassObjectSize()) + paramInfos.emplace_back(); + } + + assert(paramInfos.size() <= totalArgs && + "Did we forget to insert pass_object_size args?"); + // Add default infos for the variadic and/or suffix arguments. + paramInfos.resize(totalArgs); +} + +/// Adds the formal parameters in FPT to the given prefix. If any parameter in +/// FPT has pass_object_size attrs, then we'll add parameters for those, too. +static void appendParameterTypes(const CodeGenTypes &CGT, + SmallVectorImpl<CanQualType> &prefix, + SmallVectorImpl<FunctionProtoType::ExtParameterInfo> ¶mInfos, + CanQual<FunctionProtoType> FPT) { + // Fast path: don't touch param info if we don't need to. + if (!FPT->hasExtParameterInfos()) { + assert(paramInfos.empty() && + "We have paramInfos, but the prototype doesn't?"); + prefix.append(FPT->param_type_begin(), FPT->param_type_end()); + return; + } + + unsigned PrefixSize = prefix.size(); + // In the vast majority of cases, we'll have precisely FPT->getNumParams() + // parameters; the only thing that can change this is the presence of + // pass_object_size. So, we preallocate for the common case. + prefix.reserve(prefix.size() + FPT->getNumParams()); + + auto ExtInfos = FPT->getExtParameterInfos(); + assert(ExtInfos.size() == FPT->getNumParams()); + for (unsigned I = 0, E = FPT->getNumParams(); I != E; ++I) { + prefix.push_back(FPT->getParamType(I)); + if (ExtInfos[I].hasPassObjectSize()) + prefix.push_back(CGT.getContext().getSizeType()); + } + + addExtParameterInfosForCall(paramInfos, FPT.getTypePtr(), PrefixSize, + prefix.size()); +} + +/// Arrange the LLVM function layout for a value of the given function +/// type, on top of any implicit parameters already stored. +static const CGFunctionInfo & +arrangeLLVMFunctionInfo(CodeGenTypes &CGT, bool instanceMethod, + SmallVectorImpl<CanQualType> &prefix, + CanQual<FunctionProtoType> FTP) { + SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos; + RequiredArgs Required = RequiredArgs::forPrototypePlus(FTP, prefix.size()); + // FIXME: Kill copy. + appendParameterTypes(CGT, prefix, paramInfos, FTP); + CanQualType resultType = FTP->getReturnType().getUnqualifiedType(); + + return CGT.arrangeLLVMFunctionInfo(resultType, instanceMethod, + /*chainCall=*/false, prefix, + FTP->getExtInfo(), paramInfos, + Required); +} + +/// Arrange the argument and result information for a value of the +/// given freestanding function type. +const CGFunctionInfo & +CodeGenTypes::arrangeFreeFunctionType(CanQual<FunctionProtoType> FTP) { + SmallVector<CanQualType, 16> argTypes; + return ::arrangeLLVMFunctionInfo(*this, /*instanceMethod=*/false, argTypes, + FTP); +} + +static CallingConv getCallingConventionForDecl(const Decl *D, bool IsWindows) { + // Set the appropriate calling convention for the Function. + if (D->hasAttr<StdCallAttr>()) + return CC_X86StdCall; + + if (D->hasAttr<FastCallAttr>()) + return CC_X86FastCall; + + if (D->hasAttr<RegCallAttr>()) + return CC_X86RegCall; + + if (D->hasAttr<ThisCallAttr>()) + return CC_X86ThisCall; + + if (D->hasAttr<VectorCallAttr>()) + return CC_X86VectorCall; + + if (D->hasAttr<PascalAttr>()) + return CC_X86Pascal; + + if (PcsAttr *PCS = D->getAttr<PcsAttr>()) + return (PCS->getPCS() == PcsAttr::AAPCS ? CC_AAPCS : CC_AAPCS_VFP); + + if (D->hasAttr<AArch64VectorPcsAttr>()) + return CC_AArch64VectorCall; + + if (D->hasAttr<IntelOclBiccAttr>()) + return CC_IntelOclBicc; + + if (D->hasAttr<MSABIAttr>()) + return IsWindows ? CC_C : CC_Win64; + + if (D->hasAttr<SysVABIAttr>()) + return IsWindows ? CC_X86_64SysV : CC_C; + + if (D->hasAttr<PreserveMostAttr>()) + return CC_PreserveMost; + + if (D->hasAttr<PreserveAllAttr>()) + return CC_PreserveAll; + + return CC_C; +} + +/// Arrange the argument and result information for a call to an +/// unknown C++ non-static member function of the given abstract type. +/// (A null RD means we don't have any meaningful "this" argument type, +/// so fall back to a generic pointer type). +/// The member function must be an ordinary function, i.e. not a +/// constructor or destructor. +const CGFunctionInfo & +CodeGenTypes::arrangeCXXMethodType(const CXXRecordDecl *RD, + const FunctionProtoType *FTP, + const CXXMethodDecl *MD) { + SmallVector<CanQualType, 16> argTypes; + + // Add the 'this' pointer. + argTypes.push_back(DeriveThisType(RD, MD)); + + return ::arrangeLLVMFunctionInfo( + *this, true, argTypes, + FTP->getCanonicalTypeUnqualified().getAs<FunctionProtoType>()); +} + +/// Set calling convention for CUDA/HIP kernel. +static void setCUDAKernelCallingConvention(CanQualType &FTy, CodeGenModule &CGM, + const FunctionDecl *FD) { + if (FD->hasAttr<CUDAGlobalAttr>()) { + const FunctionType *FT = FTy->getAs<FunctionType>(); + CGM.getTargetCodeGenInfo().setCUDAKernelCallingConvention(FT); + FTy = FT->getCanonicalTypeUnqualified(); + } +} + +/// Arrange the argument and result information for a declaration or +/// definition of the given C++ non-static member function. The +/// member function must be an ordinary function, i.e. not a +/// constructor or destructor. +const CGFunctionInfo & +CodeGenTypes::arrangeCXXMethodDeclaration(const CXXMethodDecl *MD) { + assert(!isa<CXXConstructorDecl>(MD) && "wrong method for constructors!"); + assert(!isa<CXXDestructorDecl>(MD) && "wrong method for destructors!"); + + CanQualType FT = GetFormalType(MD).getAs<Type>(); + setCUDAKernelCallingConvention(FT, CGM, MD); + auto prototype = FT.getAs<FunctionProtoType>(); + + if (MD->isInstance()) { + // The abstract case is perfectly fine. + const CXXRecordDecl *ThisType = TheCXXABI.getThisArgumentTypeForMethod(MD); + return arrangeCXXMethodType(ThisType, prototype.getTypePtr(), MD); + } + + return arrangeFreeFunctionType(prototype); +} + +bool CodeGenTypes::inheritingCtorHasParams( + const InheritedConstructor &Inherited, CXXCtorType Type) { + // Parameters are unnecessary if we're constructing a base class subobject + // and the inherited constructor lives in a virtual base. + return Type == Ctor_Complete || + !Inherited.getShadowDecl()->constructsVirtualBase() || + !Target.getCXXABI().hasConstructorVariants(); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeCXXStructorDeclaration(GlobalDecl GD) { + auto *MD = cast<CXXMethodDecl>(GD.getDecl()); + + SmallVector<CanQualType, 16> argTypes; + SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos; + argTypes.push_back(DeriveThisType(MD->getParent(), MD)); + + bool PassParams = true; + + if (auto *CD = dyn_cast<CXXConstructorDecl>(MD)) { + // A base class inheriting constructor doesn't get forwarded arguments + // needed to construct a virtual base (or base class thereof). + if (auto Inherited = CD->getInheritedConstructor()) + PassParams = inheritingCtorHasParams(Inherited, GD.getCtorType()); + } + + CanQual<FunctionProtoType> FTP = GetFormalType(MD); + + // Add the formal parameters. + if (PassParams) + appendParameterTypes(*this, argTypes, paramInfos, FTP); + + CGCXXABI::AddedStructorArgs AddedArgs = + TheCXXABI.buildStructorSignature(GD, argTypes); + if (!paramInfos.empty()) { + // Note: prefix implies after the first param. + if (AddedArgs.Prefix) + paramInfos.insert(paramInfos.begin() + 1, AddedArgs.Prefix, + FunctionProtoType::ExtParameterInfo{}); + if (AddedArgs.Suffix) + paramInfos.append(AddedArgs.Suffix, + FunctionProtoType::ExtParameterInfo{}); + } + + RequiredArgs required = + (PassParams && MD->isVariadic() ? RequiredArgs(argTypes.size()) + : RequiredArgs::All); + + FunctionType::ExtInfo extInfo = FTP->getExtInfo(); + CanQualType resultType = TheCXXABI.HasThisReturn(GD) + ? argTypes.front() + : TheCXXABI.hasMostDerivedReturn(GD) + ? CGM.getContext().VoidPtrTy + : Context.VoidTy; + return arrangeLLVMFunctionInfo(resultType, /*instanceMethod=*/true, + /*chainCall=*/false, argTypes, extInfo, + paramInfos, required); +} + +static SmallVector<CanQualType, 16> +getArgTypesForCall(ASTContext &ctx, const CallArgList &args) { + SmallVector<CanQualType, 16> argTypes; + for (auto &arg : args) + argTypes.push_back(ctx.getCanonicalParamType(arg.Ty)); + return argTypes; +} + +static SmallVector<CanQualType, 16> +getArgTypesForDeclaration(ASTContext &ctx, const FunctionArgList &args) { + SmallVector<CanQualType, 16> argTypes; + for (auto &arg : args) + argTypes.push_back(ctx.getCanonicalParamType(arg->getType())); + return argTypes; +} + +static llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> +getExtParameterInfosForCall(const FunctionProtoType *proto, + unsigned prefixArgs, unsigned totalArgs) { + llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> result; + if (proto->hasExtParameterInfos()) { + addExtParameterInfosForCall(result, proto, prefixArgs, totalArgs); + } + return result; +} + +/// Arrange a call to a C++ method, passing the given arguments. +/// +/// ExtraPrefixArgs is the number of ABI-specific args passed after the `this` +/// parameter. +/// ExtraSuffixArgs is the number of ABI-specific args passed at the end of +/// args. +/// PassProtoArgs indicates whether `args` has args for the parameters in the +/// given CXXConstructorDecl. +const CGFunctionInfo & +CodeGenTypes::arrangeCXXConstructorCall(const CallArgList &args, + const CXXConstructorDecl *D, + CXXCtorType CtorKind, + unsigned ExtraPrefixArgs, + unsigned ExtraSuffixArgs, + bool PassProtoArgs) { + // FIXME: Kill copy. + SmallVector<CanQualType, 16> ArgTypes; + for (const auto &Arg : args) + ArgTypes.push_back(Context.getCanonicalParamType(Arg.Ty)); + + // +1 for implicit this, which should always be args[0]. + unsigned TotalPrefixArgs = 1 + ExtraPrefixArgs; + + CanQual<FunctionProtoType> FPT = GetFormalType(D); + RequiredArgs Required = PassProtoArgs + ? RequiredArgs::forPrototypePlus( + FPT, TotalPrefixArgs + ExtraSuffixArgs) + : RequiredArgs::All; + + GlobalDecl GD(D, CtorKind); + CanQualType ResultType = TheCXXABI.HasThisReturn(GD) + ? ArgTypes.front() + : TheCXXABI.hasMostDerivedReturn(GD) + ? CGM.getContext().VoidPtrTy + : Context.VoidTy; + + FunctionType::ExtInfo Info = FPT->getExtInfo(); + llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> ParamInfos; + // If the prototype args are elided, we should only have ABI-specific args, + // which never have param info. + if (PassProtoArgs && FPT->hasExtParameterInfos()) { + // ABI-specific suffix arguments are treated the same as variadic arguments. + addExtParameterInfosForCall(ParamInfos, FPT.getTypePtr(), TotalPrefixArgs, + ArgTypes.size()); + } + return arrangeLLVMFunctionInfo(ResultType, /*instanceMethod=*/true, + /*chainCall=*/false, ArgTypes, Info, + ParamInfos, Required); +} + +/// Arrange the argument and result information for the declaration or +/// definition of the given function. +const CGFunctionInfo & +CodeGenTypes::arrangeFunctionDeclaration(const FunctionDecl *FD) { + if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) + if (MD->isInstance()) + return arrangeCXXMethodDeclaration(MD); + + CanQualType FTy = FD->getType()->getCanonicalTypeUnqualified(); + + assert(isa<FunctionType>(FTy)); + setCUDAKernelCallingConvention(FTy, CGM, FD); + + // When declaring a function without a prototype, always use a + // non-variadic type. + if (CanQual<FunctionNoProtoType> noProto = FTy.getAs<FunctionNoProtoType>()) { + return arrangeLLVMFunctionInfo( + noProto->getReturnType(), /*instanceMethod=*/false, + /*chainCall=*/false, None, noProto->getExtInfo(), {},RequiredArgs::All); + } + + return arrangeFreeFunctionType(FTy.castAs<FunctionProtoType>()); +} + +/// Arrange the argument and result information for the declaration or +/// definition of an Objective-C method. +const CGFunctionInfo & +CodeGenTypes::arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD) { + // It happens that this is the same as a call with no optional + // arguments, except also using the formal 'self' type. + return arrangeObjCMessageSendSignature(MD, MD->getSelfDecl()->getType()); +} + +/// Arrange the argument and result information for the function type +/// through which to perform a send to the given Objective-C method, +/// using the given receiver type. The receiver type is not always +/// the 'self' type of the method or even an Objective-C pointer type. +/// This is *not* the right method for actually performing such a +/// message send, due to the possibility of optional arguments. +const CGFunctionInfo & +CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD, + QualType receiverType) { + SmallVector<CanQualType, 16> argTys; + SmallVector<FunctionProtoType::ExtParameterInfo, 4> extParamInfos(2); + argTys.push_back(Context.getCanonicalParamType(receiverType)); + argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType())); + // FIXME: Kill copy? + for (const auto *I : MD->parameters()) { + argTys.push_back(Context.getCanonicalParamType(I->getType())); + auto extParamInfo = FunctionProtoType::ExtParameterInfo().withIsNoEscape( + I->hasAttr<NoEscapeAttr>()); + extParamInfos.push_back(extParamInfo); + } + + FunctionType::ExtInfo einfo; + bool IsWindows = getContext().getTargetInfo().getTriple().isOSWindows(); + einfo = einfo.withCallingConv(getCallingConventionForDecl(MD, IsWindows)); + + if (getContext().getLangOpts().ObjCAutoRefCount && + MD->hasAttr<NSReturnsRetainedAttr>()) + einfo = einfo.withProducesResult(true); + + RequiredArgs required = + (MD->isVariadic() ? RequiredArgs(argTys.size()) : RequiredArgs::All); + + return arrangeLLVMFunctionInfo( + GetReturnType(MD->getReturnType()), /*instanceMethod=*/false, + /*chainCall=*/false, argTys, einfo, extParamInfos, required); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeUnprototypedObjCMessageSend(QualType returnType, + const CallArgList &args) { + auto argTypes = getArgTypesForCall(Context, args); + FunctionType::ExtInfo einfo; + + return arrangeLLVMFunctionInfo( + GetReturnType(returnType), /*instanceMethod=*/false, + /*chainCall=*/false, argTypes, einfo, {}, RequiredArgs::All); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeGlobalDeclaration(GlobalDecl GD) { + // FIXME: Do we need to handle ObjCMethodDecl? + const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); + + if (isa<CXXConstructorDecl>(GD.getDecl()) || + isa<CXXDestructorDecl>(GD.getDecl())) + return arrangeCXXStructorDeclaration(GD); + + return arrangeFunctionDeclaration(FD); +} + +/// Arrange a thunk that takes 'this' as the first parameter followed by +/// varargs. Return a void pointer, regardless of the actual return type. +/// The body of the thunk will end in a musttail call to a function of the +/// correct type, and the caller will bitcast the function to the correct +/// prototype. +const CGFunctionInfo & +CodeGenTypes::arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD) { + assert(MD->isVirtual() && "only methods have thunks"); + CanQual<FunctionProtoType> FTP = GetFormalType(MD); + CanQualType ArgTys[] = {DeriveThisType(MD->getParent(), MD)}; + return arrangeLLVMFunctionInfo(Context.VoidTy, /*instanceMethod=*/false, + /*chainCall=*/false, ArgTys, + FTP->getExtInfo(), {}, RequiredArgs(1)); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeMSCtorClosure(const CXXConstructorDecl *CD, + CXXCtorType CT) { + assert(CT == Ctor_CopyingClosure || CT == Ctor_DefaultClosure); + + CanQual<FunctionProtoType> FTP = GetFormalType(CD); + SmallVector<CanQualType, 2> ArgTys; + const CXXRecordDecl *RD = CD->getParent(); + ArgTys.push_back(DeriveThisType(RD, CD)); + if (CT == Ctor_CopyingClosure) + ArgTys.push_back(*FTP->param_type_begin()); + if (RD->getNumVBases() > 0) + ArgTys.push_back(Context.IntTy); + CallingConv CC = Context.getDefaultCallingConvention( + /*IsVariadic=*/false, /*IsCXXMethod=*/true); + return arrangeLLVMFunctionInfo(Context.VoidTy, /*instanceMethod=*/true, + /*chainCall=*/false, ArgTys, + FunctionType::ExtInfo(CC), {}, + RequiredArgs::All); +} + +/// Arrange a call as unto a free function, except possibly with an +/// additional number of formal parameters considered required. +static const CGFunctionInfo & +arrangeFreeFunctionLikeCall(CodeGenTypes &CGT, + CodeGenModule &CGM, + const CallArgList &args, + const FunctionType *fnType, + unsigned numExtraRequiredArgs, + bool chainCall) { + assert(args.size() >= numExtraRequiredArgs); + + llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos; + + // In most cases, there are no optional arguments. + RequiredArgs required = RequiredArgs::All; + + // If we have a variadic prototype, the required arguments are the + // extra prefix plus the arguments in the prototype. + if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) { + if (proto->isVariadic()) + required = RequiredArgs::forPrototypePlus(proto, numExtraRequiredArgs); + + if (proto->hasExtParameterInfos()) + addExtParameterInfosForCall(paramInfos, proto, numExtraRequiredArgs, + args.size()); + + // If we don't have a prototype at all, but we're supposed to + // explicitly use the variadic convention for unprototyped calls, + // treat all of the arguments as required but preserve the nominal + // possibility of variadics. + } else if (CGM.getTargetCodeGenInfo() + .isNoProtoCallVariadic(args, + cast<FunctionNoProtoType>(fnType))) { + required = RequiredArgs(args.size()); + } + + // FIXME: Kill copy. + SmallVector<CanQualType, 16> argTypes; + for (const auto &arg : args) + argTypes.push_back(CGT.getContext().getCanonicalParamType(arg.Ty)); + return CGT.arrangeLLVMFunctionInfo(GetReturnType(fnType->getReturnType()), + /*instanceMethod=*/false, chainCall, + argTypes, fnType->getExtInfo(), paramInfos, + required); +} + +/// Figure out the rules for calling a function with the given formal +/// type using the given arguments. The arguments are necessary +/// because the function might be unprototyped, in which case it's +/// target-dependent in crazy ways. +const CGFunctionInfo & +CodeGenTypes::arrangeFreeFunctionCall(const CallArgList &args, + const FunctionType *fnType, + bool chainCall) { + return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType, + chainCall ? 1 : 0, chainCall); +} + +/// A block function is essentially a free function with an +/// extra implicit argument. +const CGFunctionInfo & +CodeGenTypes::arrangeBlockFunctionCall(const CallArgList &args, + const FunctionType *fnType) { + return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType, 1, + /*chainCall=*/false); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeBlockFunctionDeclaration(const FunctionProtoType *proto, + const FunctionArgList ¶ms) { + auto paramInfos = getExtParameterInfosForCall(proto, 1, params.size()); + auto argTypes = getArgTypesForDeclaration(Context, params); + + return arrangeLLVMFunctionInfo(GetReturnType(proto->getReturnType()), + /*instanceMethod*/ false, /*chainCall*/ false, + argTypes, proto->getExtInfo(), paramInfos, + RequiredArgs::forPrototypePlus(proto, 1)); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeBuiltinFunctionCall(QualType resultType, + const CallArgList &args) { + // FIXME: Kill copy. + SmallVector<CanQualType, 16> argTypes; + for (const auto &Arg : args) + argTypes.push_back(Context.getCanonicalParamType(Arg.Ty)); + return arrangeLLVMFunctionInfo( + GetReturnType(resultType), /*instanceMethod=*/false, + /*chainCall=*/false, argTypes, FunctionType::ExtInfo(), + /*paramInfos=*/ {}, RequiredArgs::All); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeBuiltinFunctionDeclaration(QualType resultType, + const FunctionArgList &args) { + auto argTypes = getArgTypesForDeclaration(Context, args); + + return arrangeLLVMFunctionInfo( + GetReturnType(resultType), /*instanceMethod=*/false, /*chainCall=*/false, + argTypes, FunctionType::ExtInfo(), {}, RequiredArgs::All); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeBuiltinFunctionDeclaration(CanQualType resultType, + ArrayRef<CanQualType> argTypes) { + return arrangeLLVMFunctionInfo( + resultType, /*instanceMethod=*/false, /*chainCall=*/false, + argTypes, FunctionType::ExtInfo(), {}, RequiredArgs::All); +} + +/// Arrange a call to a C++ method, passing the given arguments. +/// +/// numPrefixArgs is the number of ABI-specific prefix arguments we have. It +/// does not count `this`. +const CGFunctionInfo & +CodeGenTypes::arrangeCXXMethodCall(const CallArgList &args, + const FunctionProtoType *proto, + RequiredArgs required, + unsigned numPrefixArgs) { + assert(numPrefixArgs + 1 <= args.size() && + "Emitting a call with less args than the required prefix?"); + // Add one to account for `this`. It's a bit awkward here, but we don't count + // `this` in similar places elsewhere. + auto paramInfos = + getExtParameterInfosForCall(proto, numPrefixArgs + 1, args.size()); + + // FIXME: Kill copy. + auto argTypes = getArgTypesForCall(Context, args); + + FunctionType::ExtInfo info = proto->getExtInfo(); + return arrangeLLVMFunctionInfo( + GetReturnType(proto->getReturnType()), /*instanceMethod=*/true, + /*chainCall=*/false, argTypes, info, paramInfos, required); +} + +const CGFunctionInfo &CodeGenTypes::arrangeNullaryFunction() { + return arrangeLLVMFunctionInfo( + getContext().VoidTy, /*instanceMethod=*/false, /*chainCall=*/false, + None, FunctionType::ExtInfo(), {}, RequiredArgs::All); +} + +const CGFunctionInfo & +CodeGenTypes::arrangeCall(const CGFunctionInfo &signature, + const CallArgList &args) { + assert(signature.arg_size() <= args.size()); + if (signature.arg_size() == args.size()) + return signature; + + SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos; + auto sigParamInfos = signature.getExtParameterInfos(); + if (!sigParamInfos.empty()) { + paramInfos.append(sigParamInfos.begin(), sigParamInfos.end()); + paramInfos.resize(args.size()); + } + + auto argTypes = getArgTypesForCall(Context, args); + + assert(signature.getRequiredArgs().allowsOptionalArgs()); + return arrangeLLVMFunctionInfo(signature.getReturnType(), + signature.isInstanceMethod(), + signature.isChainCall(), + argTypes, + signature.getExtInfo(), + paramInfos, + signature.getRequiredArgs()); +} + +namespace clang { +namespace CodeGen { +void computeSPIRKernelABIInfo(CodeGenModule &CGM, CGFunctionInfo &FI); +} +} + +/// Arrange the argument and result information for an abstract value +/// of a given function type. This is the method which all of the +/// above functions ultimately defer to. +const CGFunctionInfo & +CodeGenTypes::arrangeLLVMFunctionInfo(CanQualType resultType, + bool instanceMethod, + bool chainCall, + ArrayRef<CanQualType> argTypes, + FunctionType::ExtInfo info, + ArrayRef<FunctionProtoType::ExtParameterInfo> paramInfos, + RequiredArgs required) { + assert(llvm::all_of(argTypes, + [](CanQualType T) { return T.isCanonicalAsParam(); })); + + // Lookup or create unique function info. + llvm::FoldingSetNodeID ID; + CGFunctionInfo::Profile(ID, instanceMethod, chainCall, info, paramInfos, + required, resultType, argTypes); + + void *insertPos = nullptr; + CGFunctionInfo *FI = FunctionInfos.FindNodeOrInsertPos(ID, insertPos); + if (FI) + return *FI; + + unsigned CC = ClangCallConvToLLVMCallConv(info.getCC()); + + // Construct the function info. We co-allocate the ArgInfos. + FI = CGFunctionInfo::create(CC, instanceMethod, chainCall, info, + paramInfos, resultType, argTypes, required); + FunctionInfos.InsertNode(FI, insertPos); + + bool inserted = FunctionsBeingProcessed.insert(FI).second; + (void)inserted; + assert(inserted && "Recursively being processed?"); + + // Compute ABI information. + if (CC == llvm::CallingConv::SPIR_KERNEL) { + // Force target independent argument handling for the host visible + // kernel functions. + computeSPIRKernelABIInfo(CGM, *FI); + } else if (info.getCC() == CC_Swift) { + swiftcall::computeABIInfo(CGM, *FI); + } else { + getABIInfo().computeInfo(*FI); + } + + // Loop over all of the computed argument and return value info. If any of + // them are direct or extend without a specified coerce type, specify the + // default now. + ABIArgInfo &retInfo = FI->getReturnInfo(); + if (retInfo.canHaveCoerceToType() && retInfo.getCoerceToType() == nullptr) + retInfo.setCoerceToType(ConvertType(FI->getReturnType())); + + for (auto &I : FI->arguments()) + if (I.info.canHaveCoerceToType() && I.info.getCoerceToType() == nullptr) + I.info.setCoerceToType(ConvertType(I.type)); + + bool erased = FunctionsBeingProcessed.erase(FI); (void)erased; + assert(erased && "Not in set?"); + + return *FI; +} + +CGFunctionInfo *CGFunctionInfo::create(unsigned llvmCC, + bool instanceMethod, + bool chainCall, + const FunctionType::ExtInfo &info, + ArrayRef<ExtParameterInfo> paramInfos, + CanQualType resultType, + ArrayRef<CanQualType> argTypes, + RequiredArgs required) { + assert(paramInfos.empty() || paramInfos.size() == argTypes.size()); + assert(!required.allowsOptionalArgs() || + required.getNumRequiredArgs() <= argTypes.size()); + + void *buffer = + operator new(totalSizeToAlloc<ArgInfo, ExtParameterInfo>( + argTypes.size() + 1, paramInfos.size())); + + CGFunctionInfo *FI = new(buffer) CGFunctionInfo(); + FI->CallingConvention = llvmCC; + FI->EffectiveCallingConvention = llvmCC; + FI->ASTCallingConvention = info.getCC(); + FI->InstanceMethod = instanceMethod; + FI->ChainCall = chainCall; + FI->NoReturn = info.getNoReturn(); + FI->ReturnsRetained = info.getProducesResult(); + FI->NoCallerSavedRegs = info.getNoCallerSavedRegs(); + FI->NoCfCheck = info.getNoCfCheck(); + FI->Required = required; + FI->HasRegParm = info.getHasRegParm(); + FI->RegParm = info.getRegParm(); + FI->ArgStruct = nullptr; + FI->ArgStructAlign = 0; + FI->NumArgs = argTypes.size(); + FI->HasExtParameterInfos = !paramInfos.empty(); + FI->getArgsBuffer()[0].type = resultType; + for (unsigned i = 0, e = argTypes.size(); i != e; ++i) + FI->getArgsBuffer()[i + 1].type = argTypes[i]; + for (unsigned i = 0, e = paramInfos.size(); i != e; ++i) + FI->getExtParameterInfosBuffer()[i] = paramInfos[i]; + return FI; +} + +/***/ + +namespace { +// ABIArgInfo::Expand implementation. + +// Specifies the way QualType passed as ABIArgInfo::Expand is expanded. +struct TypeExpansion { + enum TypeExpansionKind { + // Elements of constant arrays are expanded recursively. + TEK_ConstantArray, + // Record fields are expanded recursively (but if record is a union, only + // the field with the largest size is expanded). + TEK_Record, + // For complex types, real and imaginary parts are expanded recursively. + TEK_Complex, + // All other types are not expandable. + TEK_None + }; + + const TypeExpansionKind Kind; + + TypeExpansion(TypeExpansionKind K) : Kind(K) {} + virtual ~TypeExpansion() {} +}; + +struct ConstantArrayExpansion : TypeExpansion { + QualType EltTy; + uint64_t NumElts; + + ConstantArrayExpansion(QualType EltTy, uint64_t NumElts) + : TypeExpansion(TEK_ConstantArray), EltTy(EltTy), NumElts(NumElts) {} + static bool classof(const TypeExpansion *TE) { + return TE->Kind == TEK_ConstantArray; + } +}; + +struct RecordExpansion : TypeExpansion { + SmallVector<const CXXBaseSpecifier *, 1> Bases; + + SmallVector<const FieldDecl *, 1> Fields; + + RecordExpansion(SmallVector<const CXXBaseSpecifier *, 1> &&Bases, + SmallVector<const FieldDecl *, 1> &&Fields) + : TypeExpansion(TEK_Record), Bases(std::move(Bases)), + Fields(std::move(Fields)) {} + static bool classof(const TypeExpansion *TE) { + return TE->Kind == TEK_Record; + } +}; + +struct ComplexExpansion : TypeExpansion { + QualType EltTy; + + ComplexExpansion(QualType EltTy) : TypeExpansion(TEK_Complex), EltTy(EltTy) {} + static bool classof(const TypeExpansion *TE) { + return TE->Kind == TEK_Complex; + } +}; + +struct NoExpansion : TypeExpansion { + NoExpansion() : TypeExpansion(TEK_None) {} + static bool classof(const TypeExpansion *TE) { + return TE->Kind == TEK_None; + } +}; +} // namespace + +static std::unique_ptr<TypeExpansion> +getTypeExpansion(QualType Ty, const ASTContext &Context) { + if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) { + return std::make_unique<ConstantArrayExpansion>( + AT->getElementType(), AT->getSize().getZExtValue()); + } + if (const RecordType *RT = Ty->getAs<RecordType>()) { + SmallVector<const CXXBaseSpecifier *, 1> Bases; + SmallVector<const FieldDecl *, 1> Fields; + const RecordDecl *RD = RT->getDecl(); + assert(!RD->hasFlexibleArrayMember() && + "Cannot expand structure with flexible array."); + if (RD->isUnion()) { + // Unions can be here only in degenerative cases - all the fields are same + // after flattening. Thus we have to use the "largest" field. + const FieldDecl *LargestFD = nullptr; + CharUnits UnionSize = CharUnits::Zero(); + + for (const auto *FD : RD->fields()) { + if (FD->isZeroLengthBitField(Context)) + continue; + assert(!FD->isBitField() && + "Cannot expand structure with bit-field members."); + CharUnits FieldSize = Context.getTypeSizeInChars(FD->getType()); + if (UnionSize < FieldSize) { + UnionSize = FieldSize; + LargestFD = FD; + } + } + if (LargestFD) + Fields.push_back(LargestFD); + } else { + if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { + assert(!CXXRD->isDynamicClass() && + "cannot expand vtable pointers in dynamic classes"); + for (const CXXBaseSpecifier &BS : CXXRD->bases()) + Bases.push_back(&BS); + } + + for (const auto *FD : RD->fields()) { + if (FD->isZeroLengthBitField(Context)) + continue; + assert(!FD->isBitField() && + "Cannot expand structure with bit-field members."); + Fields.push_back(FD); + } + } + return std::make_unique<RecordExpansion>(std::move(Bases), + std::move(Fields)); + } + if (const ComplexType *CT = Ty->getAs<ComplexType>()) { + return std::make_unique<ComplexExpansion>(CT->getElementType()); + } + return std::make_unique<NoExpansion>(); +} + +static int getExpansionSize(QualType Ty, const ASTContext &Context) { + auto Exp = getTypeExpansion(Ty, Context); + if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) { + return CAExp->NumElts * getExpansionSize(CAExp->EltTy, Context); + } + if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) { + int Res = 0; + for (auto BS : RExp->Bases) + Res += getExpansionSize(BS->getType(), Context); + for (auto FD : RExp->Fields) + Res += getExpansionSize(FD->getType(), Context); + return Res; + } + if (isa<ComplexExpansion>(Exp.get())) + return 2; + assert(isa<NoExpansion>(Exp.get())); + return 1; +} + +void +CodeGenTypes::getExpandedTypes(QualType Ty, + SmallVectorImpl<llvm::Type *>::iterator &TI) { + auto Exp = getTypeExpansion(Ty, Context); + if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) { + for (int i = 0, n = CAExp->NumElts; i < n; i++) { + getExpandedTypes(CAExp->EltTy, TI); + } + } else if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) { + for (auto BS : RExp->Bases) + getExpandedTypes(BS->getType(), TI); + for (auto FD : RExp->Fields) + getExpandedTypes(FD->getType(), TI); + } else if (auto CExp = dyn_cast<ComplexExpansion>(Exp.get())) { + llvm::Type *EltTy = ConvertType(CExp->EltTy); + *TI++ = EltTy; + *TI++ = EltTy; + } else { + assert(isa<NoExpansion>(Exp.get())); + *TI++ = ConvertType(Ty); + } +} + +static void forConstantArrayExpansion(CodeGenFunction &CGF, + ConstantArrayExpansion *CAE, + Address BaseAddr, + llvm::function_ref<void(Address)> Fn) { + CharUnits EltSize = CGF.getContext().getTypeSizeInChars(CAE->EltTy); + CharUnits EltAlign = + BaseAddr.getAlignment().alignmentOfArrayElement(EltSize); + + for (int i = 0, n = CAE->NumElts; i < n; i++) { + llvm::Value *EltAddr = + CGF.Builder.CreateConstGEP2_32(nullptr, BaseAddr.getPointer(), 0, i); + Fn(Address(EltAddr, EltAlign)); + } +} + +void CodeGenFunction::ExpandTypeFromArgs( + QualType Ty, LValue LV, SmallVectorImpl<llvm::Value *>::iterator &AI) { + assert(LV.isSimple() && + "Unexpected non-simple lvalue during struct expansion."); + + auto Exp = getTypeExpansion(Ty, getContext()); + if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) { + forConstantArrayExpansion(*this, CAExp, LV.getAddress(), + [&](Address EltAddr) { + LValue LV = MakeAddrLValue(EltAddr, CAExp->EltTy); + ExpandTypeFromArgs(CAExp->EltTy, LV, AI); + }); + } else if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) { + Address This = LV.getAddress(); + for (const CXXBaseSpecifier *BS : RExp->Bases) { + // Perform a single step derived-to-base conversion. + Address Base = + GetAddressOfBaseClass(This, Ty->getAsCXXRecordDecl(), &BS, &BS + 1, + /*NullCheckValue=*/false, SourceLocation()); + LValue SubLV = MakeAddrLValue(Base, BS->getType()); + + // Recurse onto bases. + ExpandTypeFromArgs(BS->getType(), SubLV, AI); + } + for (auto FD : RExp->Fields) { + // FIXME: What are the right qualifiers here? + LValue SubLV = EmitLValueForFieldInitialization(LV, FD); + ExpandTypeFromArgs(FD->getType(), SubLV, AI); + } + } else if (isa<ComplexExpansion>(Exp.get())) { + auto realValue = *AI++; + auto imagValue = *AI++; + EmitStoreOfComplex(ComplexPairTy(realValue, imagValue), LV, /*init*/ true); + } else { + assert(isa<NoExpansion>(Exp.get())); + EmitStoreThroughLValue(RValue::get(*AI++), LV); + } +} + +void CodeGenFunction::ExpandTypeToArgs( + QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy, + SmallVectorImpl<llvm::Value *> &IRCallArgs, unsigned &IRCallArgPos) { + auto Exp = getTypeExpansion(Ty, getContext()); + if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) { + Address Addr = Arg.hasLValue() ? Arg.getKnownLValue().getAddress() + : Arg.getKnownRValue().getAggregateAddress(); + forConstantArrayExpansion( + *this, CAExp, Addr, [&](Address EltAddr) { + CallArg EltArg = CallArg( + convertTempToRValue(EltAddr, CAExp->EltTy, SourceLocation()), + CAExp->EltTy); + ExpandTypeToArgs(CAExp->EltTy, EltArg, IRFuncTy, IRCallArgs, + IRCallArgPos); + }); + } else if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) { + Address This = Arg.hasLValue() ? Arg.getKnownLValue().getAddress() + : Arg.getKnownRValue().getAggregateAddress(); + for (const CXXBaseSpecifier *BS : RExp->Bases) { + // Perform a single step derived-to-base conversion. + Address Base = + GetAddressOfBaseClass(This, Ty->getAsCXXRecordDecl(), &BS, &BS + 1, + /*NullCheckValue=*/false, SourceLocation()); + CallArg BaseArg = CallArg(RValue::getAggregate(Base), BS->getType()); + + // Recurse onto bases. + ExpandTypeToArgs(BS->getType(), BaseArg, IRFuncTy, IRCallArgs, + IRCallArgPos); + } + + LValue LV = MakeAddrLValue(This, Ty); + for (auto FD : RExp->Fields) { + CallArg FldArg = + CallArg(EmitRValueForField(LV, FD, SourceLocation()), FD->getType()); + ExpandTypeToArgs(FD->getType(), FldArg, IRFuncTy, IRCallArgs, + IRCallArgPos); + } + } else if (isa<ComplexExpansion>(Exp.get())) { + ComplexPairTy CV = Arg.getKnownRValue().getComplexVal(); + IRCallArgs[IRCallArgPos++] = CV.first; + IRCallArgs[IRCallArgPos++] = CV.second; + } else { + assert(isa<NoExpansion>(Exp.get())); + auto RV = Arg.getKnownRValue(); + assert(RV.isScalar() && + "Unexpected non-scalar rvalue during struct expansion."); + + // Insert a bitcast as needed. + llvm::Value *V = RV.getScalarVal(); + if (IRCallArgPos < IRFuncTy->getNumParams() && + V->getType() != IRFuncTy->getParamType(IRCallArgPos)) + V = Builder.CreateBitCast(V, IRFuncTy->getParamType(IRCallArgPos)); + + IRCallArgs[IRCallArgPos++] = V; + } +} + +/// Create a temporary allocation for the purposes of coercion. +static Address CreateTempAllocaForCoercion(CodeGenFunction &CGF, llvm::Type *Ty, + CharUnits MinAlign) { + // Don't use an alignment that's worse than what LLVM would prefer. + auto PrefAlign = CGF.CGM.getDataLayout().getPrefTypeAlignment(Ty); + CharUnits Align = std::max(MinAlign, CharUnits::fromQuantity(PrefAlign)); + + return CGF.CreateTempAlloca(Ty, Align); +} + +/// EnterStructPointerForCoercedAccess - Given a struct pointer that we are +/// accessing some number of bytes out of it, try to gep into the struct to get +/// at its inner goodness. Dive as deep as possible without entering an element +/// with an in-memory size smaller than DstSize. +static Address +EnterStructPointerForCoercedAccess(Address SrcPtr, + llvm::StructType *SrcSTy, + uint64_t DstSize, CodeGenFunction &CGF) { + // We can't dive into a zero-element struct. + if (SrcSTy->getNumElements() == 0) return SrcPtr; + + llvm::Type *FirstElt = SrcSTy->getElementType(0); + + // If the first elt is at least as large as what we're looking for, or if the + // first element is the same size as the whole struct, we can enter it. The + // comparison must be made on the store size and not the alloca size. Using + // the alloca size may overstate the size of the load. + uint64_t FirstEltSize = + CGF.CGM.getDataLayout().getTypeStoreSize(FirstElt); + if (FirstEltSize < DstSize && + FirstEltSize < CGF.CGM.getDataLayout().getTypeStoreSize(SrcSTy)) + return SrcPtr; + + // GEP into the first element. + SrcPtr = CGF.Builder.CreateStructGEP(SrcPtr, 0, "coerce.dive"); + + // If the first element is a struct, recurse. + llvm::Type *SrcTy = SrcPtr.getElementType(); + if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy)) + return EnterStructPointerForCoercedAccess(SrcPtr, SrcSTy, DstSize, CGF); + + return SrcPtr; +} + +/// CoerceIntOrPtrToIntOrPtr - Convert a value Val to the specific Ty where both +/// are either integers or pointers. This does a truncation of the value if it +/// is too large or a zero extension if it is too small. +/// +/// This behaves as if the value were coerced through memory, so on big-endian +/// targets the high bits are preserved in a truncation, while little-endian +/// targets preserve the low bits. +static llvm::Value *CoerceIntOrPtrToIntOrPtr(llvm::Value *Val, + llvm::Type *Ty, + CodeGenFunction &CGF) { + if (Val->getType() == Ty) + return Val; + + if (isa<llvm::PointerType>(Val->getType())) { + // If this is Pointer->Pointer avoid conversion to and from int. + if (isa<llvm::PointerType>(Ty)) + return CGF.Builder.CreateBitCast(Val, Ty, "coerce.val"); + + // Convert the pointer to an integer so we can play with its width. + Val = CGF.Builder.CreatePtrToInt(Val, CGF.IntPtrTy, "coerce.val.pi"); + } + + llvm::Type *DestIntTy = Ty; + if (isa<llvm::PointerType>(DestIntTy)) + DestIntTy = CGF.IntPtrTy; + + if (Val->getType() != DestIntTy) { + const llvm::DataLayout &DL = CGF.CGM.getDataLayout(); + if (DL.isBigEndian()) { + // Preserve the high bits on big-endian targets. + // That is what memory coercion does. + uint64_t SrcSize = DL.getTypeSizeInBits(Val->getType()); + uint64_t DstSize = DL.getTypeSizeInBits(DestIntTy); + + if (SrcSize > DstSize) { + Val = CGF.Builder.CreateLShr(Val, SrcSize - DstSize, "coerce.highbits"); + Val = CGF.Builder.CreateTrunc(Val, DestIntTy, "coerce.val.ii"); + } else { + Val = CGF.Builder.CreateZExt(Val, DestIntTy, "coerce.val.ii"); + Val = CGF.Builder.CreateShl(Val, DstSize - SrcSize, "coerce.highbits"); + } + } else { + // Little-endian targets preserve the low bits. No shifts required. + Val = CGF.Builder.CreateIntCast(Val, DestIntTy, false, "coerce.val.ii"); + } + } + + if (isa<llvm::PointerType>(Ty)) + Val = CGF.Builder.CreateIntToPtr(Val, Ty, "coerce.val.ip"); + return Val; +} + + + +/// CreateCoercedLoad - Create a load from \arg SrcPtr interpreted as +/// a pointer to an object of type \arg Ty, known to be aligned to +/// \arg SrcAlign bytes. +/// +/// This safely handles the case when the src type is smaller than the +/// destination type; in this situation the values of bits which not +/// present in the src are undefined. +static llvm::Value *CreateCoercedLoad(Address Src, llvm::Type *Ty, + CodeGenFunction &CGF) { + llvm::Type *SrcTy = Src.getElementType(); + + // If SrcTy and Ty are the same, just do a load. + if (SrcTy == Ty) + return CGF.Builder.CreateLoad(Src); + + uint64_t DstSize = CGF.CGM.getDataLayout().getTypeAllocSize(Ty); + + if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy)) { + Src = EnterStructPointerForCoercedAccess(Src, SrcSTy, DstSize, CGF); + SrcTy = Src.getType()->getElementType(); + } + + uint64_t SrcSize = CGF.CGM.getDataLayout().getTypeAllocSize(SrcTy); + + // If the source and destination are integer or pointer types, just do an + // extension or truncation to the desired type. + if ((isa<llvm::IntegerType>(Ty) || isa<llvm::PointerType>(Ty)) && + (isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy))) { + llvm::Value *Load = CGF.Builder.CreateLoad(Src); + return CoerceIntOrPtrToIntOrPtr(Load, Ty, CGF); + } + + // If load is legal, just bitcast the src pointer. + if (SrcSize >= DstSize) { + // Generally SrcSize is never greater than DstSize, since this means we are + // losing bits. However, this can happen in cases where the structure has + // additional padding, for example due to a user specified alignment. + // + // FIXME: Assert that we aren't truncating non-padding bits when have access + // to that information. + Src = CGF.Builder.CreateBitCast(Src, + Ty->getPointerTo(Src.getAddressSpace())); + return CGF.Builder.CreateLoad(Src); + } + + // Otherwise do coercion through memory. This is stupid, but simple. + Address Tmp = CreateTempAllocaForCoercion(CGF, Ty, Src.getAlignment()); + Address Casted = CGF.Builder.CreateElementBitCast(Tmp,CGF.Int8Ty); + Address SrcCasted = CGF.Builder.CreateElementBitCast(Src,CGF.Int8Ty); + CGF.Builder.CreateMemCpy(Casted, SrcCasted, + llvm::ConstantInt::get(CGF.IntPtrTy, SrcSize), + false); + return CGF.Builder.CreateLoad(Tmp); +} + +// Function to store a first-class aggregate into memory. We prefer to +// store the elements rather than the aggregate to be more friendly to +// fast-isel. +// FIXME: Do we need to recurse here? +static void BuildAggStore(CodeGenFunction &CGF, llvm::Value *Val, + Address Dest, bool DestIsVolatile) { + // Prefer scalar stores to first-class aggregate stores. + if (llvm::StructType *STy = + dyn_cast<llvm::StructType>(Val->getType())) { + for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { + Address EltPtr = CGF.Builder.CreateStructGEP(Dest, i); + llvm::Value *Elt = CGF.Builder.CreateExtractValue(Val, i); + CGF.Builder.CreateStore(Elt, EltPtr, DestIsVolatile); + } + } else { + CGF.Builder.CreateStore(Val, Dest, DestIsVolatile); + } +} + +/// CreateCoercedStore - Create a store to \arg DstPtr from \arg Src, +/// where the source and destination may have different types. The +/// destination is known to be aligned to \arg DstAlign bytes. +/// +/// This safely handles the case when the src type is larger than the +/// destination type; the upper bits of the src will be lost. +static void CreateCoercedStore(llvm::Value *Src, + Address Dst, + bool DstIsVolatile, + CodeGenFunction &CGF) { + llvm::Type *SrcTy = Src->getType(); + llvm::Type *DstTy = Dst.getType()->getElementType(); + if (SrcTy == DstTy) { + CGF.Builder.CreateStore(Src, Dst, DstIsVolatile); + return; + } + + uint64_t SrcSize = CGF.CGM.getDataLayout().getTypeAllocSize(SrcTy); + + if (llvm::StructType *DstSTy = dyn_cast<llvm::StructType>(DstTy)) { + Dst = EnterStructPointerForCoercedAccess(Dst, DstSTy, SrcSize, CGF); + DstTy = Dst.getType()->getElementType(); + } + + // If the source and destination are integer or pointer types, just do an + // extension or truncation to the desired type. + if ((isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy)) && + (isa<llvm::IntegerType>(DstTy) || isa<llvm::PointerType>(DstTy))) { + Src = CoerceIntOrPtrToIntOrPtr(Src, DstTy, CGF); + CGF.Builder.CreateStore(Src, Dst, DstIsVolatile); + return; + } + + uint64_t DstSize = CGF.CGM.getDataLayout().getTypeAllocSize(DstTy); + + // If store is legal, just bitcast the src pointer. + if (SrcSize <= DstSize) { + Dst = CGF.Builder.CreateElementBitCast(Dst, SrcTy); + BuildAggStore(CGF, Src, Dst, DstIsVolatile); + } else { + // Otherwise do coercion through memory. This is stupid, but + // simple. + + // Generally SrcSize is never greater than DstSize, since this means we are + // losing bits. However, this can happen in cases where the structure has + // additional padding, for example due to a user specified alignment. + // + // FIXME: Assert that we aren't truncating non-padding bits when have access + // to that information. + Address Tmp = CreateTempAllocaForCoercion(CGF, SrcTy, Dst.getAlignment()); + CGF.Builder.CreateStore(Src, Tmp); + Address Casted = CGF.Builder.CreateElementBitCast(Tmp,CGF.Int8Ty); + Address DstCasted = CGF.Builder.CreateElementBitCast(Dst,CGF.Int8Ty); + CGF.Builder.CreateMemCpy(DstCasted, Casted, + llvm::ConstantInt::get(CGF.IntPtrTy, DstSize), + false); + } +} + +static Address emitAddressAtOffset(CodeGenFunction &CGF, Address addr, + const ABIArgInfo &info) { + if (unsigned offset = info.getDirectOffset()) { + addr = CGF.Builder.CreateElementBitCast(addr, CGF.Int8Ty); + addr = CGF.Builder.CreateConstInBoundsByteGEP(addr, + CharUnits::fromQuantity(offset)); + addr = CGF.Builder.CreateElementBitCast(addr, info.getCoerceToType()); + } + return addr; +} + +namespace { + +/// Encapsulates information about the way function arguments from +/// CGFunctionInfo should be passed to actual LLVM IR function. +class ClangToLLVMArgMapping { + static const unsigned InvalidIndex = ~0U; + unsigned InallocaArgNo; + unsigned SRetArgNo; + unsigned TotalIRArgs; + + /// Arguments of LLVM IR function corresponding to single Clang argument. + struct IRArgs { + unsigned PaddingArgIndex; + // Argument is expanded to IR arguments at positions + // [FirstArgIndex, FirstArgIndex + NumberOfArgs). + unsigned FirstArgIndex; + unsigned NumberOfArgs; + + IRArgs() + : PaddingArgIndex(InvalidIndex), FirstArgIndex(InvalidIndex), + NumberOfArgs(0) {} + }; + + SmallVector<IRArgs, 8> ArgInfo; + +public: + ClangToLLVMArgMapping(const ASTContext &Context, const CGFunctionInfo &FI, + bool OnlyRequiredArgs = false) + : InallocaArgNo(InvalidIndex), SRetArgNo(InvalidIndex), TotalIRArgs(0), + ArgInfo(OnlyRequiredArgs ? FI.getNumRequiredArgs() : FI.arg_size()) { + construct(Context, FI, OnlyRequiredArgs); + } + + bool hasInallocaArg() const { return InallocaArgNo != InvalidIndex; } + unsigned getInallocaArgNo() const { + assert(hasInallocaArg()); + return InallocaArgNo; + } + + bool hasSRetArg() const { return SRetArgNo != InvalidIndex; } + unsigned getSRetArgNo() const { + assert(hasSRetArg()); + return SRetArgNo; + } + + unsigned totalIRArgs() const { return TotalIRArgs; } + + bool hasPaddingArg(unsigned ArgNo) const { + assert(ArgNo < ArgInfo.size()); + return ArgInfo[ArgNo].PaddingArgIndex != InvalidIndex; + } + unsigned getPaddingArgNo(unsigned ArgNo) const { + assert(hasPaddingArg(ArgNo)); + return ArgInfo[ArgNo].PaddingArgIndex; + } + + /// Returns index of first IR argument corresponding to ArgNo, and their + /// quantity. + std::pair<unsigned, unsigned> getIRArgs(unsigned ArgNo) const { + assert(ArgNo < ArgInfo.size()); + return std::make_pair(ArgInfo[ArgNo].FirstArgIndex, + ArgInfo[ArgNo].NumberOfArgs); + } + +private: + void construct(const ASTContext &Context, const CGFunctionInfo &FI, + bool OnlyRequiredArgs); +}; + +void ClangToLLVMArgMapping::construct(const ASTContext &Context, + const CGFunctionInfo &FI, + bool OnlyRequiredArgs) { + unsigned IRArgNo = 0; + bool SwapThisWithSRet = false; + const ABIArgInfo &RetAI = FI.getReturnInfo(); + + if (RetAI.getKind() == ABIArgInfo::Indirect) { + SwapThisWithSRet = RetAI.isSRetAfterThis(); + SRetArgNo = SwapThisWithSRet ? 1 : IRArgNo++; + } + + unsigned ArgNo = 0; + unsigned NumArgs = OnlyRequiredArgs ? FI.getNumRequiredArgs() : FI.arg_size(); + for (CGFunctionInfo::const_arg_iterator I = FI.arg_begin(); ArgNo < NumArgs; + ++I, ++ArgNo) { + assert(I != FI.arg_end()); + QualType ArgType = I->type; + const ABIArgInfo &AI = I->info; + // Collect data about IR arguments corresponding to Clang argument ArgNo. + auto &IRArgs = ArgInfo[ArgNo]; + + if (AI.getPaddingType()) + IRArgs.PaddingArgIndex = IRArgNo++; + + switch (AI.getKind()) { + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: { + // FIXME: handle sseregparm someday... + llvm::StructType *STy = dyn_cast<llvm::StructType>(AI.getCoerceToType()); + if (AI.isDirect() && AI.getCanBeFlattened() && STy) { + IRArgs.NumberOfArgs = STy->getNumElements(); + } else { + IRArgs.NumberOfArgs = 1; + } + break; + } + case ABIArgInfo::Indirect: + IRArgs.NumberOfArgs = 1; + break; + case ABIArgInfo::Ignore: + case ABIArgInfo::InAlloca: + // ignore and inalloca doesn't have matching LLVM parameters. + IRArgs.NumberOfArgs = 0; + break; + case ABIArgInfo::CoerceAndExpand: + IRArgs.NumberOfArgs = AI.getCoerceAndExpandTypeSequence().size(); + break; + case ABIArgInfo::Expand: + IRArgs.NumberOfArgs = getExpansionSize(ArgType, Context); + break; + } + + if (IRArgs.NumberOfArgs > 0) { + IRArgs.FirstArgIndex = IRArgNo; + IRArgNo += IRArgs.NumberOfArgs; + } + + // Skip over the sret parameter when it comes second. We already handled it + // above. + if (IRArgNo == 1 && SwapThisWithSRet) + IRArgNo++; + } + assert(ArgNo == ArgInfo.size()); + + if (FI.usesInAlloca()) + InallocaArgNo = IRArgNo++; + + TotalIRArgs = IRArgNo; +} +} // namespace + +/***/ + +bool CodeGenModule::ReturnTypeUsesSRet(const CGFunctionInfo &FI) { + const auto &RI = FI.getReturnInfo(); + return RI.isIndirect() || (RI.isInAlloca() && RI.getInAllocaSRet()); +} + +bool CodeGenModule::ReturnSlotInterferesWithArgs(const CGFunctionInfo &FI) { + return ReturnTypeUsesSRet(FI) && + getTargetCodeGenInfo().doesReturnSlotInterfereWithArgs(); +} + +bool CodeGenModule::ReturnTypeUsesFPRet(QualType ResultType) { + if (const BuiltinType *BT = ResultType->getAs<BuiltinType>()) { + switch (BT->getKind()) { + default: + return false; + case BuiltinType::Float: + return getTarget().useObjCFPRetForRealType(TargetInfo::Float); + case BuiltinType::Double: + return getTarget().useObjCFPRetForRealType(TargetInfo::Double); + case BuiltinType::LongDouble: + return getTarget().useObjCFPRetForRealType(TargetInfo::LongDouble); + } + } + + return false; +} + +bool CodeGenModule::ReturnTypeUsesFP2Ret(QualType ResultType) { + if (const ComplexType *CT = ResultType->getAs<ComplexType>()) { + if (const BuiltinType *BT = CT->getElementType()->getAs<BuiltinType>()) { + if (BT->getKind() == BuiltinType::LongDouble) + return getTarget().useObjCFP2RetForComplexLongDouble(); + } + } + + return false; +} + +llvm::FunctionType *CodeGenTypes::GetFunctionType(GlobalDecl GD) { + const CGFunctionInfo &FI = arrangeGlobalDeclaration(GD); + return GetFunctionType(FI); +} + +llvm::FunctionType * +CodeGenTypes::GetFunctionType(const CGFunctionInfo &FI) { + + bool Inserted = FunctionsBeingProcessed.insert(&FI).second; + (void)Inserted; + assert(Inserted && "Recursively being processed?"); + + llvm::Type *resultType = nullptr; + const ABIArgInfo &retAI = FI.getReturnInfo(); + switch (retAI.getKind()) { + case ABIArgInfo::Expand: + llvm_unreachable("Invalid ABI kind for return argument"); + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: + resultType = retAI.getCoerceToType(); + break; + + case ABIArgInfo::InAlloca: + if (retAI.getInAllocaSRet()) { + // sret things on win32 aren't void, they return the sret pointer. + QualType ret = FI.getReturnType(); + llvm::Type *ty = ConvertType(ret); + unsigned addressSpace = Context.getTargetAddressSpace(ret); + resultType = llvm::PointerType::get(ty, addressSpace); + } else { + resultType = llvm::Type::getVoidTy(getLLVMContext()); + } + break; + + case ABIArgInfo::Indirect: + case ABIArgInfo::Ignore: + resultType = llvm::Type::getVoidTy(getLLVMContext()); + break; + + case ABIArgInfo::CoerceAndExpand: + resultType = retAI.getUnpaddedCoerceAndExpandType(); + break; + } + + ClangToLLVMArgMapping IRFunctionArgs(getContext(), FI, true); + SmallVector<llvm::Type*, 8> ArgTypes(IRFunctionArgs.totalIRArgs()); + + // Add type for sret argument. + if (IRFunctionArgs.hasSRetArg()) { + QualType Ret = FI.getReturnType(); + llvm::Type *Ty = ConvertType(Ret); + unsigned AddressSpace = Context.getTargetAddressSpace(Ret); + ArgTypes[IRFunctionArgs.getSRetArgNo()] = + llvm::PointerType::get(Ty, AddressSpace); + } + + // Add type for inalloca argument. + if (IRFunctionArgs.hasInallocaArg()) { + auto ArgStruct = FI.getArgStruct(); + assert(ArgStruct); + ArgTypes[IRFunctionArgs.getInallocaArgNo()] = ArgStruct->getPointerTo(); + } + + // Add in all of the required arguments. + unsigned ArgNo = 0; + CGFunctionInfo::const_arg_iterator it = FI.arg_begin(), + ie = it + FI.getNumRequiredArgs(); + for (; it != ie; ++it, ++ArgNo) { + const ABIArgInfo &ArgInfo = it->info; + + // Insert a padding type to ensure proper alignment. + if (IRFunctionArgs.hasPaddingArg(ArgNo)) + ArgTypes[IRFunctionArgs.getPaddingArgNo(ArgNo)] = + ArgInfo.getPaddingType(); + + unsigned FirstIRArg, NumIRArgs; + std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo); + + switch (ArgInfo.getKind()) { + case ABIArgInfo::Ignore: + case ABIArgInfo::InAlloca: + assert(NumIRArgs == 0); + break; + + case ABIArgInfo::Indirect: { + assert(NumIRArgs == 1); + // indirect arguments are always on the stack, which is alloca addr space. + llvm::Type *LTy = ConvertTypeForMem(it->type); + ArgTypes[FirstIRArg] = LTy->getPointerTo( + CGM.getDataLayout().getAllocaAddrSpace()); + break; + } + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: { + // Fast-isel and the optimizer generally like scalar values better than + // FCAs, so we flatten them if this is safe to do for this argument. + llvm::Type *argType = ArgInfo.getCoerceToType(); + llvm::StructType *st = dyn_cast<llvm::StructType>(argType); + if (st && ArgInfo.isDirect() && ArgInfo.getCanBeFlattened()) { + assert(NumIRArgs == st->getNumElements()); + for (unsigned i = 0, e = st->getNumElements(); i != e; ++i) + ArgTypes[FirstIRArg + i] = st->getElementType(i); + } else { + assert(NumIRArgs == 1); + ArgTypes[FirstIRArg] = argType; + } + break; + } + + case ABIArgInfo::CoerceAndExpand: { + auto ArgTypesIter = ArgTypes.begin() + FirstIRArg; + for (auto EltTy : ArgInfo.getCoerceAndExpandTypeSequence()) { + *ArgTypesIter++ = EltTy; + } + assert(ArgTypesIter == ArgTypes.begin() + FirstIRArg + NumIRArgs); + break; + } + + case ABIArgInfo::Expand: + auto ArgTypesIter = ArgTypes.begin() + FirstIRArg; + getExpandedTypes(it->type, ArgTypesIter); + assert(ArgTypesIter == ArgTypes.begin() + FirstIRArg + NumIRArgs); + break; + } + } + + bool Erased = FunctionsBeingProcessed.erase(&FI); (void)Erased; + assert(Erased && "Not in set?"); + + return llvm::FunctionType::get(resultType, ArgTypes, FI.isVariadic()); +} + +llvm::Type *CodeGenTypes::GetFunctionTypeForVTable(GlobalDecl GD) { + const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl()); + const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>(); + + if (!isFuncTypeConvertible(FPT)) + return llvm::StructType::get(getLLVMContext()); + + return GetFunctionType(GD); +} + +static void AddAttributesFromFunctionProtoType(ASTContext &Ctx, + llvm::AttrBuilder &FuncAttrs, + const FunctionProtoType *FPT) { + if (!FPT) + return; + + if (!isUnresolvedExceptionSpec(FPT->getExceptionSpecType()) && + FPT->isNothrow()) + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); +} + +void CodeGenModule::ConstructDefaultFnAttrList(StringRef Name, bool HasOptnone, + bool AttrOnCallSite, + llvm::AttrBuilder &FuncAttrs) { + // OptimizeNoneAttr takes precedence over -Os or -Oz. No warning needed. + if (!HasOptnone) { + if (CodeGenOpts.OptimizeSize) + FuncAttrs.addAttribute(llvm::Attribute::OptimizeForSize); + if (CodeGenOpts.OptimizeSize == 2) + FuncAttrs.addAttribute(llvm::Attribute::MinSize); + } + + if (CodeGenOpts.DisableRedZone) + FuncAttrs.addAttribute(llvm::Attribute::NoRedZone); + if (CodeGenOpts.IndirectTlsSegRefs) + FuncAttrs.addAttribute("indirect-tls-seg-refs"); + if (CodeGenOpts.NoImplicitFloat) + FuncAttrs.addAttribute(llvm::Attribute::NoImplicitFloat); + + if (AttrOnCallSite) { + // Attributes that should go on the call site only. + if (!CodeGenOpts.SimplifyLibCalls || + CodeGenOpts.isNoBuiltinFunc(Name.data())) + FuncAttrs.addAttribute(llvm::Attribute::NoBuiltin); + if (!CodeGenOpts.TrapFuncName.empty()) + FuncAttrs.addAttribute("trap-func-name", CodeGenOpts.TrapFuncName); + } else { + StringRef FpKind; + switch (CodeGenOpts.getFramePointer()) { + case CodeGenOptions::FramePointerKind::None: + FpKind = "none"; + break; + case CodeGenOptions::FramePointerKind::NonLeaf: + FpKind = "non-leaf"; + break; + case CodeGenOptions::FramePointerKind::All: + FpKind = "all"; + break; + } + FuncAttrs.addAttribute("frame-pointer", FpKind); + + FuncAttrs.addAttribute("less-precise-fpmad", + llvm::toStringRef(CodeGenOpts.LessPreciseFPMAD)); + + if (CodeGenOpts.NullPointerIsValid) + FuncAttrs.addAttribute("null-pointer-is-valid", "true"); + if (!CodeGenOpts.FPDenormalMode.empty()) + FuncAttrs.addAttribute("denormal-fp-math", CodeGenOpts.FPDenormalMode); + + FuncAttrs.addAttribute("no-trapping-math", + llvm::toStringRef(CodeGenOpts.NoTrappingMath)); + + // Strict (compliant) code is the default, so only add this attribute to + // indicate that we are trying to workaround a problem case. + if (!CodeGenOpts.StrictFloatCastOverflow) + FuncAttrs.addAttribute("strict-float-cast-overflow", "false"); + + // TODO: Are these all needed? + // unsafe/inf/nan/nsz are handled by instruction-level FastMathFlags. + FuncAttrs.addAttribute("no-infs-fp-math", + llvm::toStringRef(CodeGenOpts.NoInfsFPMath)); + FuncAttrs.addAttribute("no-nans-fp-math", + llvm::toStringRef(CodeGenOpts.NoNaNsFPMath)); + FuncAttrs.addAttribute("unsafe-fp-math", + llvm::toStringRef(CodeGenOpts.UnsafeFPMath)); + FuncAttrs.addAttribute("use-soft-float", + llvm::toStringRef(CodeGenOpts.SoftFloat)); + FuncAttrs.addAttribute("stack-protector-buffer-size", + llvm::utostr(CodeGenOpts.SSPBufferSize)); + FuncAttrs.addAttribute("no-signed-zeros-fp-math", + llvm::toStringRef(CodeGenOpts.NoSignedZeros)); + FuncAttrs.addAttribute( + "correctly-rounded-divide-sqrt-fp-math", + llvm::toStringRef(CodeGenOpts.CorrectlyRoundedDivSqrt)); + + if (getLangOpts().OpenCL) + FuncAttrs.addAttribute("denorms-are-zero", + llvm::toStringRef(CodeGenOpts.FlushDenorm)); + + // TODO: Reciprocal estimate codegen options should apply to instructions? + const std::vector<std::string> &Recips = CodeGenOpts.Reciprocals; + if (!Recips.empty()) + FuncAttrs.addAttribute("reciprocal-estimates", + llvm::join(Recips, ",")); + + if (!CodeGenOpts.PreferVectorWidth.empty() && + CodeGenOpts.PreferVectorWidth != "none") + FuncAttrs.addAttribute("prefer-vector-width", + CodeGenOpts.PreferVectorWidth); + + if (CodeGenOpts.StackRealignment) + FuncAttrs.addAttribute("stackrealign"); + if (CodeGenOpts.Backchain) + FuncAttrs.addAttribute("backchain"); + + if (CodeGenOpts.SpeculativeLoadHardening) + FuncAttrs.addAttribute(llvm::Attribute::SpeculativeLoadHardening); + } + + if (getLangOpts().assumeFunctionsAreConvergent()) { + // Conservatively, mark all functions and calls in CUDA and OpenCL as + // convergent (meaning, they may call an intrinsically convergent op, such + // as __syncthreads() / barrier(), and so can't have certain optimizations + // applied around them). LLVM will remove this attribute where it safely + // can. + FuncAttrs.addAttribute(llvm::Attribute::Convergent); + } + + if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) { + // Exceptions aren't supported in CUDA device code. + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + + // Respect -fcuda-flush-denormals-to-zero. + if (CodeGenOpts.FlushDenorm) + FuncAttrs.addAttribute("nvptx-f32ftz", "true"); + } + + for (StringRef Attr : CodeGenOpts.DefaultFunctionAttrs) { + StringRef Var, Value; + std::tie(Var, Value) = Attr.split('='); + FuncAttrs.addAttribute(Var, Value); + } +} + +void CodeGenModule::AddDefaultFnAttrs(llvm::Function &F) { + llvm::AttrBuilder FuncAttrs; + ConstructDefaultFnAttrList(F.getName(), F.hasOptNone(), + /* AttrOnCallSite = */ false, FuncAttrs); + F.addAttributes(llvm::AttributeList::FunctionIndex, FuncAttrs); +} + +void CodeGenModule::ConstructAttributeList( + StringRef Name, const CGFunctionInfo &FI, CGCalleeInfo CalleeInfo, + llvm::AttributeList &AttrList, unsigned &CallingConv, bool AttrOnCallSite) { + llvm::AttrBuilder FuncAttrs; + llvm::AttrBuilder RetAttrs; + + CallingConv = FI.getEffectiveCallingConvention(); + if (FI.isNoReturn()) + FuncAttrs.addAttribute(llvm::Attribute::NoReturn); + + // If we have information about the function prototype, we can learn + // attributes from there. + AddAttributesFromFunctionProtoType(getContext(), FuncAttrs, + CalleeInfo.getCalleeFunctionProtoType()); + + const Decl *TargetDecl = CalleeInfo.getCalleeDecl().getDecl(); + + bool HasOptnone = false; + // FIXME: handle sseregparm someday... + if (TargetDecl) { + if (TargetDecl->hasAttr<ReturnsTwiceAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::ReturnsTwice); + if (TargetDecl->hasAttr<NoThrowAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + if (TargetDecl->hasAttr<NoReturnAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::NoReturn); + if (TargetDecl->hasAttr<ColdAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::Cold); + if (TargetDecl->hasAttr<NoDuplicateAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::NoDuplicate); + if (TargetDecl->hasAttr<ConvergentAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::Convergent); + + if (const FunctionDecl *Fn = dyn_cast<FunctionDecl>(TargetDecl)) { + AddAttributesFromFunctionProtoType( + getContext(), FuncAttrs, Fn->getType()->getAs<FunctionProtoType>()); + // Don't use [[noreturn]] or _Noreturn for a call to a virtual function. + // These attributes are not inherited by overloads. + const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn); + if (Fn->isNoReturn() && !(AttrOnCallSite && MD && MD->isVirtual())) + FuncAttrs.addAttribute(llvm::Attribute::NoReturn); + } + + // 'const', 'pure' and 'noalias' attributed functions are also nounwind. + if (TargetDecl->hasAttr<ConstAttr>()) { + FuncAttrs.addAttribute(llvm::Attribute::ReadNone); + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + } else if (TargetDecl->hasAttr<PureAttr>()) { + FuncAttrs.addAttribute(llvm::Attribute::ReadOnly); + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + } else if (TargetDecl->hasAttr<NoAliasAttr>()) { + FuncAttrs.addAttribute(llvm::Attribute::ArgMemOnly); + FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + } + if (TargetDecl->hasAttr<RestrictAttr>()) + RetAttrs.addAttribute(llvm::Attribute::NoAlias); + if (TargetDecl->hasAttr<ReturnsNonNullAttr>() && + !CodeGenOpts.NullPointerIsValid) + RetAttrs.addAttribute(llvm::Attribute::NonNull); + if (TargetDecl->hasAttr<AnyX86NoCallerSavedRegistersAttr>()) + FuncAttrs.addAttribute("no_caller_saved_registers"); + if (TargetDecl->hasAttr<AnyX86NoCfCheckAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::NoCfCheck); + + HasOptnone = TargetDecl->hasAttr<OptimizeNoneAttr>(); + if (auto *AllocSize = TargetDecl->getAttr<AllocSizeAttr>()) { + Optional<unsigned> NumElemsParam; + if (AllocSize->getNumElemsParam().isValid()) + NumElemsParam = AllocSize->getNumElemsParam().getLLVMIndex(); + FuncAttrs.addAllocSizeAttr(AllocSize->getElemSizeParam().getLLVMIndex(), + NumElemsParam); + } + } + + ConstructDefaultFnAttrList(Name, HasOptnone, AttrOnCallSite, FuncAttrs); + + // This must run after constructing the default function attribute list + // to ensure that the speculative load hardening attribute is removed + // in the case where the -mspeculative-load-hardening flag was passed. + if (TargetDecl) { + if (TargetDecl->hasAttr<NoSpeculativeLoadHardeningAttr>()) + FuncAttrs.removeAttribute(llvm::Attribute::SpeculativeLoadHardening); + if (TargetDecl->hasAttr<SpeculativeLoadHardeningAttr>()) + FuncAttrs.addAttribute(llvm::Attribute::SpeculativeLoadHardening); + } + + if (CodeGenOpts.EnableSegmentedStacks && + !(TargetDecl && TargetDecl->hasAttr<NoSplitStackAttr>())) + FuncAttrs.addAttribute("split-stack"); + + // Add NonLazyBind attribute to function declarations when -fno-plt + // is used. + if (TargetDecl && CodeGenOpts.NoPLT) { + if (auto *Fn = dyn_cast<FunctionDecl>(TargetDecl)) { + if (!Fn->isDefined() && !AttrOnCallSite) { + FuncAttrs.addAttribute(llvm::Attribute::NonLazyBind); + } + } + } + + if (TargetDecl && TargetDecl->hasAttr<OpenCLKernelAttr>()) { + if (getLangOpts().OpenCLVersion <= 120) { + // OpenCL v1.2 Work groups are always uniform + FuncAttrs.addAttribute("uniform-work-group-size", "true"); + } else { + // OpenCL v2.0 Work groups may be whether uniform or not. + // '-cl-uniform-work-group-size' compile option gets a hint + // to the compiler that the global work-size be a multiple of + // the work-group size specified to clEnqueueNDRangeKernel + // (i.e. work groups are uniform). + FuncAttrs.addAttribute("uniform-work-group-size", + llvm::toStringRef(CodeGenOpts.UniformWGSize)); + } + } + + if (!AttrOnCallSite) { + bool DisableTailCalls = false; + + if (CodeGenOpts.DisableTailCalls) + DisableTailCalls = true; + else if (TargetDecl) { + if (TargetDecl->hasAttr<DisableTailCallsAttr>() || + TargetDecl->hasAttr<AnyX86InterruptAttr>()) + DisableTailCalls = true; + else if (CodeGenOpts.NoEscapingBlockTailCalls) { + if (const auto *BD = dyn_cast<BlockDecl>(TargetDecl)) + if (!BD->doesNotEscape()) + DisableTailCalls = true; + } + } + + FuncAttrs.addAttribute("disable-tail-calls", + llvm::toStringRef(DisableTailCalls)); + GetCPUAndFeaturesAttributes(CalleeInfo.getCalleeDecl(), FuncAttrs); + } + + ClangToLLVMArgMapping IRFunctionArgs(getContext(), FI); + + QualType RetTy = FI.getReturnType(); + const ABIArgInfo &RetAI = FI.getReturnInfo(); + switch (RetAI.getKind()) { + case ABIArgInfo::Extend: + if (RetAI.isSignExt()) + RetAttrs.addAttribute(llvm::Attribute::SExt); + else + RetAttrs.addAttribute(llvm::Attribute::ZExt); + LLVM_FALLTHROUGH; + case ABIArgInfo::Direct: + if (RetAI.getInReg()) + RetAttrs.addAttribute(llvm::Attribute::InReg); + break; + case ABIArgInfo::Ignore: + break; + + case ABIArgInfo::InAlloca: + case ABIArgInfo::Indirect: { + // inalloca and sret disable readnone and readonly + FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly) + .removeAttribute(llvm::Attribute::ReadNone); + break; + } + + case ABIArgInfo::CoerceAndExpand: + break; + + case ABIArgInfo::Expand: + llvm_unreachable("Invalid ABI kind for return argument"); + } + + if (const auto *RefTy = RetTy->getAs<ReferenceType>()) { + QualType PTy = RefTy->getPointeeType(); + if (!PTy->isIncompleteType() && PTy->isConstantSizeType()) + RetAttrs.addDereferenceableAttr(getContext().getTypeSizeInChars(PTy) + .getQuantity()); + else if (getContext().getTargetAddressSpace(PTy) == 0 && + !CodeGenOpts.NullPointerIsValid) + RetAttrs.addAttribute(llvm::Attribute::NonNull); + } + + bool hasUsedSRet = false; + SmallVector<llvm::AttributeSet, 4> ArgAttrs(IRFunctionArgs.totalIRArgs()); + + // Attach attributes to sret. + if (IRFunctionArgs.hasSRetArg()) { + llvm::AttrBuilder SRETAttrs; + SRETAttrs.addAttribute(llvm::Attribute::StructRet); + hasUsedSRet = true; + if (RetAI.getInReg()) + SRETAttrs.addAttribute(llvm::Attribute::InReg); + ArgAttrs[IRFunctionArgs.getSRetArgNo()] = + llvm::AttributeSet::get(getLLVMContext(), SRETAttrs); + } + + // Attach attributes to inalloca argument. + if (IRFunctionArgs.hasInallocaArg()) { + llvm::AttrBuilder Attrs; + Attrs.addAttribute(llvm::Attribute::InAlloca); + ArgAttrs[IRFunctionArgs.getInallocaArgNo()] = + llvm::AttributeSet::get(getLLVMContext(), Attrs); + } + + unsigned ArgNo = 0; + for (CGFunctionInfo::const_arg_iterator I = FI.arg_begin(), + E = FI.arg_end(); + I != E; ++I, ++ArgNo) { + QualType ParamType = I->type; + const ABIArgInfo &AI = I->info; + llvm::AttrBuilder Attrs; + + // Add attribute for padding argument, if necessary. + if (IRFunctionArgs.hasPaddingArg(ArgNo)) { + if (AI.getPaddingInReg()) { + ArgAttrs[IRFunctionArgs.getPaddingArgNo(ArgNo)] = + llvm::AttributeSet::get( + getLLVMContext(), + llvm::AttrBuilder().addAttribute(llvm::Attribute::InReg)); + } + } + + // 'restrict' -> 'noalias' is done in EmitFunctionProlog when we + // have the corresponding parameter variable. It doesn't make + // sense to do it here because parameters are so messed up. + switch (AI.getKind()) { + case ABIArgInfo::Extend: + if (AI.isSignExt()) + Attrs.addAttribute(llvm::Attribute::SExt); + else + Attrs.addAttribute(llvm::Attribute::ZExt); + LLVM_FALLTHROUGH; + case ABIArgInfo::Direct: + if (ArgNo == 0 && FI.isChainCall()) + Attrs.addAttribute(llvm::Attribute::Nest); + else if (AI.getInReg()) + Attrs.addAttribute(llvm::Attribute::InReg); + break; + + case ABIArgInfo::Indirect: { + if (AI.getInReg()) + Attrs.addAttribute(llvm::Attribute::InReg); + + if (AI.getIndirectByVal()) + Attrs.addByValAttr(getTypes().ConvertTypeForMem(ParamType)); + + CharUnits Align = AI.getIndirectAlign(); + + // In a byval argument, it is important that the required + // alignment of the type is honored, as LLVM might be creating a + // *new* stack object, and needs to know what alignment to give + // it. (Sometimes it can deduce a sensible alignment on its own, + // but not if clang decides it must emit a packed struct, or the + // user specifies increased alignment requirements.) + // + // This is different from indirect *not* byval, where the object + // exists already, and the align attribute is purely + // informative. + assert(!Align.isZero()); + + // For now, only add this when we have a byval argument. + // TODO: be less lazy about updating test cases. + if (AI.getIndirectByVal()) + Attrs.addAlignmentAttr(Align.getQuantity()); + + // byval disables readnone and readonly. + FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly) + .removeAttribute(llvm::Attribute::ReadNone); + break; + } + case ABIArgInfo::Ignore: + case ABIArgInfo::Expand: + case ABIArgInfo::CoerceAndExpand: + break; + + case ABIArgInfo::InAlloca: + // inalloca disables readnone and readonly. + FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly) + .removeAttribute(llvm::Attribute::ReadNone); + continue; + } + + if (const auto *RefTy = ParamType->getAs<ReferenceType>()) { + QualType PTy = RefTy->getPointeeType(); + if (!PTy->isIncompleteType() && PTy->isConstantSizeType()) + Attrs.addDereferenceableAttr(getContext().getTypeSizeInChars(PTy) + .getQuantity()); + else if (getContext().getTargetAddressSpace(PTy) == 0 && + !CodeGenOpts.NullPointerIsValid) + Attrs.addAttribute(llvm::Attribute::NonNull); + } + + switch (FI.getExtParameterInfo(ArgNo).getABI()) { + case ParameterABI::Ordinary: + break; + + case ParameterABI::SwiftIndirectResult: { + // Add 'sret' if we haven't already used it for something, but + // only if the result is void. + if (!hasUsedSRet && RetTy->isVoidType()) { + Attrs.addAttribute(llvm::Attribute::StructRet); + hasUsedSRet = true; + } + + // Add 'noalias' in either case. + Attrs.addAttribute(llvm::Attribute::NoAlias); + + // Add 'dereferenceable' and 'alignment'. + auto PTy = ParamType->getPointeeType(); + if (!PTy->isIncompleteType() && PTy->isConstantSizeType()) { + auto info = getContext().getTypeInfoInChars(PTy); + Attrs.addDereferenceableAttr(info.first.getQuantity()); + Attrs.addAttribute(llvm::Attribute::getWithAlignment( + getLLVMContext(), info.second.getAsAlign())); + } + break; + } + + case ParameterABI::SwiftErrorResult: + Attrs.addAttribute(llvm::Attribute::SwiftError); + break; + + case ParameterABI::SwiftContext: + Attrs.addAttribute(llvm::Attribute::SwiftSelf); + break; + } + + if (FI.getExtParameterInfo(ArgNo).isNoEscape()) + Attrs.addAttribute(llvm::Attribute::NoCapture); + + if (Attrs.hasAttributes()) { + unsigned FirstIRArg, NumIRArgs; + std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo); + for (unsigned i = 0; i < NumIRArgs; i++) + ArgAttrs[FirstIRArg + i] = + llvm::AttributeSet::get(getLLVMContext(), Attrs); + } + } + assert(ArgNo == FI.arg_size()); + + AttrList = llvm::AttributeList::get( + getLLVMContext(), llvm::AttributeSet::get(getLLVMContext(), FuncAttrs), + llvm::AttributeSet::get(getLLVMContext(), RetAttrs), ArgAttrs); +} + +/// An argument came in as a promoted argument; demote it back to its +/// declared type. +static llvm::Value *emitArgumentDemotion(CodeGenFunction &CGF, + const VarDecl *var, + llvm::Value *value) { + llvm::Type *varType = CGF.ConvertType(var->getType()); + + // This can happen with promotions that actually don't change the + // underlying type, like the enum promotions. + if (value->getType() == varType) return value; + + assert((varType->isIntegerTy() || varType->isFloatingPointTy()) + && "unexpected promotion type"); + + if (isa<llvm::IntegerType>(varType)) + return CGF.Builder.CreateTrunc(value, varType, "arg.unpromote"); + + return CGF.Builder.CreateFPCast(value, varType, "arg.unpromote"); +} + +/// Returns the attribute (either parameter attribute, or function +/// attribute), which declares argument ArgNo to be non-null. +static const NonNullAttr *getNonNullAttr(const Decl *FD, const ParmVarDecl *PVD, + QualType ArgType, unsigned ArgNo) { + // FIXME: __attribute__((nonnull)) can also be applied to: + // - references to pointers, where the pointee is known to be + // nonnull (apparently a Clang extension) + // - transparent unions containing pointers + // In the former case, LLVM IR cannot represent the constraint. In + // the latter case, we have no guarantee that the transparent union + // is in fact passed as a pointer. + if (!ArgType->isAnyPointerType() && !ArgType->isBlockPointerType()) + return nullptr; + // First, check attribute on parameter itself. + if (PVD) { + if (auto ParmNNAttr = PVD->getAttr<NonNullAttr>()) + return ParmNNAttr; + } + // Check function attributes. + if (!FD) + return nullptr; + for (const auto *NNAttr : FD->specific_attrs<NonNullAttr>()) { + if (NNAttr->isNonNull(ArgNo)) + return NNAttr; + } + return nullptr; +} + +namespace { + struct CopyBackSwiftError final : EHScopeStack::Cleanup { + Address Temp; + Address Arg; + CopyBackSwiftError(Address temp, Address arg) : Temp(temp), Arg(arg) {} + void Emit(CodeGenFunction &CGF, Flags flags) override { + llvm::Value *errorValue = CGF.Builder.CreateLoad(Temp); + CGF.Builder.CreateStore(errorValue, Arg); + } + }; +} + +void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI, + llvm::Function *Fn, + const FunctionArgList &Args) { + if (CurCodeDecl && CurCodeDecl->hasAttr<NakedAttr>()) + // Naked functions don't have prologues. + return; + + // If this is an implicit-return-zero function, go ahead and + // initialize the return value. TODO: it might be nice to have + // a more general mechanism for this that didn't require synthesized + // return statements. + if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurCodeDecl)) { + if (FD->hasImplicitReturnZero()) { + QualType RetTy = FD->getReturnType().getUnqualifiedType(); + llvm::Type* LLVMTy = CGM.getTypes().ConvertType(RetTy); + llvm::Constant* Zero = llvm::Constant::getNullValue(LLVMTy); + Builder.CreateStore(Zero, ReturnValue); + } + } + + // FIXME: We no longer need the types from FunctionArgList; lift up and + // simplify. + + ClangToLLVMArgMapping IRFunctionArgs(CGM.getContext(), FI); + // Flattened function arguments. + SmallVector<llvm::Value *, 16> FnArgs; + FnArgs.reserve(IRFunctionArgs.totalIRArgs()); + for (auto &Arg : Fn->args()) { + FnArgs.push_back(&Arg); + } + assert(FnArgs.size() == IRFunctionArgs.totalIRArgs()); + + // If we're using inalloca, all the memory arguments are GEPs off of the last + // parameter, which is a pointer to the complete memory area. + Address ArgStruct = Address::invalid(); + if (IRFunctionArgs.hasInallocaArg()) { + ArgStruct = Address(FnArgs[IRFunctionArgs.getInallocaArgNo()], + FI.getArgStructAlignment()); + + assert(ArgStruct.getType() == FI.getArgStruct()->getPointerTo()); + } + + // Name the struct return parameter. + if (IRFunctionArgs.hasSRetArg()) { + auto AI = cast<llvm::Argument>(FnArgs[IRFunctionArgs.getSRetArgNo()]); + AI->setName("agg.result"); + AI->addAttr(llvm::Attribute::NoAlias); + } + + // Track if we received the parameter as a pointer (indirect, byval, or + // inalloca). If already have a pointer, EmitParmDecl doesn't need to copy it + // into a local alloca for us. + SmallVector<ParamValue, 16> ArgVals; + ArgVals.reserve(Args.size()); + + // Create a pointer value for every parameter declaration. This usually + // entails copying one or more LLVM IR arguments into an alloca. Don't push + // any cleanups or do anything that might unwind. We do that separately, so + // we can push the cleanups in the correct order for the ABI. + assert(FI.arg_size() == Args.size() && + "Mismatch between function signature & arguments."); + unsigned ArgNo = 0; + CGFunctionInfo::const_arg_iterator info_it = FI.arg_begin(); + for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end(); + i != e; ++i, ++info_it, ++ArgNo) { + const VarDecl *Arg = *i; + const ABIArgInfo &ArgI = info_it->info; + + bool isPromoted = + isa<ParmVarDecl>(Arg) && cast<ParmVarDecl>(Arg)->isKNRPromoted(); + // We are converting from ABIArgInfo type to VarDecl type directly, unless + // the parameter is promoted. In this case we convert to + // CGFunctionInfo::ArgInfo type with subsequent argument demotion. + QualType Ty = isPromoted ? info_it->type : Arg->getType(); + assert(hasScalarEvaluationKind(Ty) == + hasScalarEvaluationKind(Arg->getType())); + + unsigned FirstIRArg, NumIRArgs; + std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo); + + switch (ArgI.getKind()) { + case ABIArgInfo::InAlloca: { + assert(NumIRArgs == 0); + auto FieldIndex = ArgI.getInAllocaFieldIndex(); + Address V = + Builder.CreateStructGEP(ArgStruct, FieldIndex, Arg->getName()); + ArgVals.push_back(ParamValue::forIndirect(V)); + break; + } + + case ABIArgInfo::Indirect: { + assert(NumIRArgs == 1); + Address ParamAddr = Address(FnArgs[FirstIRArg], ArgI.getIndirectAlign()); + + if (!hasScalarEvaluationKind(Ty)) { + // Aggregates and complex variables are accessed by reference. All we + // need to do is realign the value, if requested. + Address V = ParamAddr; + if (ArgI.getIndirectRealign()) { + Address AlignedTemp = CreateMemTemp(Ty, "coerce"); + + // Copy from the incoming argument pointer to the temporary with the + // appropriate alignment. + // + // FIXME: We should have a common utility for generating an aggregate + // copy. + CharUnits Size = getContext().getTypeSizeInChars(Ty); + auto SizeVal = llvm::ConstantInt::get(IntPtrTy, Size.getQuantity()); + Address Dst = Builder.CreateBitCast(AlignedTemp, Int8PtrTy); + Address Src = Builder.CreateBitCast(ParamAddr, Int8PtrTy); + Builder.CreateMemCpy(Dst, Src, SizeVal, false); + V = AlignedTemp; + } + ArgVals.push_back(ParamValue::forIndirect(V)); + } else { + // Load scalar value from indirect argument. + llvm::Value *V = + EmitLoadOfScalar(ParamAddr, false, Ty, Arg->getBeginLoc()); + + if (isPromoted) + V = emitArgumentDemotion(*this, Arg, V); + ArgVals.push_back(ParamValue::forDirect(V)); + } + break; + } + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: { + + // If we have the trivial case, handle it with no muss and fuss. + if (!isa<llvm::StructType>(ArgI.getCoerceToType()) && + ArgI.getCoerceToType() == ConvertType(Ty) && + ArgI.getDirectOffset() == 0) { + assert(NumIRArgs == 1); + llvm::Value *V = FnArgs[FirstIRArg]; + auto AI = cast<llvm::Argument>(V); + + if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(Arg)) { + if (getNonNullAttr(CurCodeDecl, PVD, PVD->getType(), + PVD->getFunctionScopeIndex()) && + !CGM.getCodeGenOpts().NullPointerIsValid) + AI->addAttr(llvm::Attribute::NonNull); + + QualType OTy = PVD->getOriginalType(); + if (const auto *ArrTy = + getContext().getAsConstantArrayType(OTy)) { + // A C99 array parameter declaration with the static keyword also + // indicates dereferenceability, and if the size is constant we can + // use the dereferenceable attribute (which requires the size in + // bytes). + if (ArrTy->getSizeModifier() == ArrayType::Static) { + QualType ETy = ArrTy->getElementType(); + uint64_t ArrSize = ArrTy->getSize().getZExtValue(); + if (!ETy->isIncompleteType() && ETy->isConstantSizeType() && + ArrSize) { + llvm::AttrBuilder Attrs; + Attrs.addDereferenceableAttr( + getContext().getTypeSizeInChars(ETy).getQuantity()*ArrSize); + AI->addAttrs(Attrs); + } else if (getContext().getTargetAddressSpace(ETy) == 0 && + !CGM.getCodeGenOpts().NullPointerIsValid) { + AI->addAttr(llvm::Attribute::NonNull); + } + } + } else if (const auto *ArrTy = + getContext().getAsVariableArrayType(OTy)) { + // For C99 VLAs with the static keyword, we don't know the size so + // we can't use the dereferenceable attribute, but in addrspace(0) + // we know that it must be nonnull. + if (ArrTy->getSizeModifier() == VariableArrayType::Static && + !getContext().getTargetAddressSpace(ArrTy->getElementType()) && + !CGM.getCodeGenOpts().NullPointerIsValid) + AI->addAttr(llvm::Attribute::NonNull); + } + + const auto *AVAttr = PVD->getAttr<AlignValueAttr>(); + if (!AVAttr) + if (const auto *TOTy = dyn_cast<TypedefType>(OTy)) + AVAttr = TOTy->getDecl()->getAttr<AlignValueAttr>(); + if (AVAttr && !SanOpts.has(SanitizerKind::Alignment)) { + // If alignment-assumption sanitizer is enabled, we do *not* add + // alignment attribute here, but emit normal alignment assumption, + // so the UBSAN check could function. + llvm::Value *AlignmentValue = + EmitScalarExpr(AVAttr->getAlignment()); + llvm::ConstantInt *AlignmentCI = + cast<llvm::ConstantInt>(AlignmentValue); + unsigned Alignment = std::min((unsigned)AlignmentCI->getZExtValue(), + +llvm::Value::MaximumAlignment); + AI->addAttrs(llvm::AttrBuilder().addAlignmentAttr(Alignment)); + } + } + + if (Arg->getType().isRestrictQualified()) + AI->addAttr(llvm::Attribute::NoAlias); + + // LLVM expects swifterror parameters to be used in very restricted + // ways. Copy the value into a less-restricted temporary. + if (FI.getExtParameterInfo(ArgNo).getABI() + == ParameterABI::SwiftErrorResult) { + QualType pointeeTy = Ty->getPointeeType(); + assert(pointeeTy->isPointerType()); + Address temp = + CreateMemTemp(pointeeTy, getPointerAlign(), "swifterror.temp"); + Address arg = Address(V, getContext().getTypeAlignInChars(pointeeTy)); + llvm::Value *incomingErrorValue = Builder.CreateLoad(arg); + Builder.CreateStore(incomingErrorValue, temp); + V = temp.getPointer(); + + // Push a cleanup to copy the value back at the end of the function. + // The convention does not guarantee that the value will be written + // back if the function exits with an unwind exception. + EHStack.pushCleanup<CopyBackSwiftError>(NormalCleanup, temp, arg); + } + + // Ensure the argument is the correct type. + if (V->getType() != ArgI.getCoerceToType()) + V = Builder.CreateBitCast(V, ArgI.getCoerceToType()); + + if (isPromoted) + V = emitArgumentDemotion(*this, Arg, V); + + // Because of merging of function types from multiple decls it is + // possible for the type of an argument to not match the corresponding + // type in the function type. Since we are codegening the callee + // in here, add a cast to the argument type. + llvm::Type *LTy = ConvertType(Arg->getType()); + if (V->getType() != LTy) + V = Builder.CreateBitCast(V, LTy); + + ArgVals.push_back(ParamValue::forDirect(V)); + break; + } + + Address Alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg), + Arg->getName()); + + // Pointer to store into. + Address Ptr = emitAddressAtOffset(*this, Alloca, ArgI); + + // Fast-isel and the optimizer generally like scalar values better than + // FCAs, so we flatten them if this is safe to do for this argument. + llvm::StructType *STy = dyn_cast<llvm::StructType>(ArgI.getCoerceToType()); + if (ArgI.isDirect() && ArgI.getCanBeFlattened() && STy && + STy->getNumElements() > 1) { + uint64_t SrcSize = CGM.getDataLayout().getTypeAllocSize(STy); + llvm::Type *DstTy = Ptr.getElementType(); + uint64_t DstSize = CGM.getDataLayout().getTypeAllocSize(DstTy); + + Address AddrToStoreInto = Address::invalid(); + if (SrcSize <= DstSize) { + AddrToStoreInto = Builder.CreateElementBitCast(Ptr, STy); + } else { + AddrToStoreInto = + CreateTempAlloca(STy, Alloca.getAlignment(), "coerce"); + } + + assert(STy->getNumElements() == NumIRArgs); + for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { + auto AI = FnArgs[FirstIRArg + i]; + AI->setName(Arg->getName() + ".coerce" + Twine(i)); + Address EltPtr = Builder.CreateStructGEP(AddrToStoreInto, i); + Builder.CreateStore(AI, EltPtr); + } + + if (SrcSize > DstSize) { + Builder.CreateMemCpy(Ptr, AddrToStoreInto, DstSize); + } + + } else { + // Simple case, just do a coerced store of the argument into the alloca. + assert(NumIRArgs == 1); + auto AI = FnArgs[FirstIRArg]; + AI->setName(Arg->getName() + ".coerce"); + CreateCoercedStore(AI, Ptr, /*DstIsVolatile=*/false, *this); + } + + // Match to what EmitParmDecl is expecting for this type. + if (CodeGenFunction::hasScalarEvaluationKind(Ty)) { + llvm::Value *V = + EmitLoadOfScalar(Alloca, false, Ty, Arg->getBeginLoc()); + if (isPromoted) + V = emitArgumentDemotion(*this, Arg, V); + ArgVals.push_back(ParamValue::forDirect(V)); + } else { + ArgVals.push_back(ParamValue::forIndirect(Alloca)); + } + break; + } + + case ABIArgInfo::CoerceAndExpand: { + // Reconstruct into a temporary. + Address alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg)); + ArgVals.push_back(ParamValue::forIndirect(alloca)); + + auto coercionType = ArgI.getCoerceAndExpandType(); + alloca = Builder.CreateElementBitCast(alloca, coercionType); + + unsigned argIndex = FirstIRArg; + for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) { + llvm::Type *eltType = coercionType->getElementType(i); + if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType)) + continue; + + auto eltAddr = Builder.CreateStructGEP(alloca, i); + auto elt = FnArgs[argIndex++]; + Builder.CreateStore(elt, eltAddr); + } + assert(argIndex == FirstIRArg + NumIRArgs); + break; + } + + case ABIArgInfo::Expand: { + // If this structure was expanded into multiple arguments then + // we need to create a temporary and reconstruct it from the + // arguments. + Address Alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg)); + LValue LV = MakeAddrLValue(Alloca, Ty); + ArgVals.push_back(ParamValue::forIndirect(Alloca)); + + auto FnArgIter = FnArgs.begin() + FirstIRArg; + ExpandTypeFromArgs(Ty, LV, FnArgIter); + assert(FnArgIter == FnArgs.begin() + FirstIRArg + NumIRArgs); + for (unsigned i = 0, e = NumIRArgs; i != e; ++i) { + auto AI = FnArgs[FirstIRArg + i]; + AI->setName(Arg->getName() + "." + Twine(i)); + } + break; + } + + case ABIArgInfo::Ignore: + assert(NumIRArgs == 0); + // Initialize the local variable appropriately. + if (!hasScalarEvaluationKind(Ty)) { + ArgVals.push_back(ParamValue::forIndirect(CreateMemTemp(Ty))); + } else { + llvm::Value *U = llvm::UndefValue::get(ConvertType(Arg->getType())); + ArgVals.push_back(ParamValue::forDirect(U)); + } + break; + } + } + + if (getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) { + for (int I = Args.size() - 1; I >= 0; --I) + EmitParmDecl(*Args[I], ArgVals[I], I + 1); + } else { + for (unsigned I = 0, E = Args.size(); I != E; ++I) + EmitParmDecl(*Args[I], ArgVals[I], I + 1); + } +} + +static void eraseUnusedBitCasts(llvm::Instruction *insn) { + while (insn->use_empty()) { + llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(insn); + if (!bitcast) return; + + // This is "safe" because we would have used a ConstantExpr otherwise. + insn = cast<llvm::Instruction>(bitcast->getOperand(0)); + bitcast->eraseFromParent(); + } +} + +/// Try to emit a fused autorelease of a return result. +static llvm::Value *tryEmitFusedAutoreleaseOfResult(CodeGenFunction &CGF, + llvm::Value *result) { + // We must be immediately followed the cast. + llvm::BasicBlock *BB = CGF.Builder.GetInsertBlock(); + if (BB->empty()) return nullptr; + if (&BB->back() != result) return nullptr; + + llvm::Type *resultType = result->getType(); + + // result is in a BasicBlock and is therefore an Instruction. + llvm::Instruction *generator = cast<llvm::Instruction>(result); + + SmallVector<llvm::Instruction *, 4> InstsToKill; + + // Look for: + // %generator = bitcast %type1* %generator2 to %type2* + while (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(generator)) { + // We would have emitted this as a constant if the operand weren't + // an Instruction. + generator = cast<llvm::Instruction>(bitcast->getOperand(0)); + + // Require the generator to be immediately followed by the cast. + if (generator->getNextNode() != bitcast) + return nullptr; + + InstsToKill.push_back(bitcast); + } + + // Look for: + // %generator = call i8* @objc_retain(i8* %originalResult) + // or + // %generator = call i8* @objc_retainAutoreleasedReturnValue(i8* %originalResult) + llvm::CallInst *call = dyn_cast<llvm::CallInst>(generator); + if (!call) return nullptr; + + bool doRetainAutorelease; + + if (call->getCalledValue() == CGF.CGM.getObjCEntrypoints().objc_retain) { + doRetainAutorelease = true; + } else if (call->getCalledValue() == CGF.CGM.getObjCEntrypoints() + .objc_retainAutoreleasedReturnValue) { + doRetainAutorelease = false; + + // If we emitted an assembly marker for this call (and the + // ARCEntrypoints field should have been set if so), go looking + // for that call. If we can't find it, we can't do this + // optimization. But it should always be the immediately previous + // instruction, unless we needed bitcasts around the call. + if (CGF.CGM.getObjCEntrypoints().retainAutoreleasedReturnValueMarker) { + llvm::Instruction *prev = call->getPrevNode(); + assert(prev); + if (isa<llvm::BitCastInst>(prev)) { + prev = prev->getPrevNode(); + assert(prev); + } + assert(isa<llvm::CallInst>(prev)); + assert(cast<llvm::CallInst>(prev)->getCalledValue() == + CGF.CGM.getObjCEntrypoints().retainAutoreleasedReturnValueMarker); + InstsToKill.push_back(prev); + } + } else { + return nullptr; + } + + result = call->getArgOperand(0); + InstsToKill.push_back(call); + + // Keep killing bitcasts, for sanity. Note that we no longer care + // about precise ordering as long as there's exactly one use. + while (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(result)) { + if (!bitcast->hasOneUse()) break; + InstsToKill.push_back(bitcast); + result = bitcast->getOperand(0); + } + + // Delete all the unnecessary instructions, from latest to earliest. + for (auto *I : InstsToKill) + I->eraseFromParent(); + + // Do the fused retain/autorelease if we were asked to. + if (doRetainAutorelease) + result = CGF.EmitARCRetainAutoreleaseReturnValue(result); + + // Cast back to the result type. + return CGF.Builder.CreateBitCast(result, resultType); +} + +/// If this is a +1 of the value of an immutable 'self', remove it. +static llvm::Value *tryRemoveRetainOfSelf(CodeGenFunction &CGF, + llvm::Value *result) { + // This is only applicable to a method with an immutable 'self'. + const ObjCMethodDecl *method = + dyn_cast_or_null<ObjCMethodDecl>(CGF.CurCodeDecl); + if (!method) return nullptr; + const VarDecl *self = method->getSelfDecl(); + if (!self->getType().isConstQualified()) return nullptr; + + // Look for a retain call. + llvm::CallInst *retainCall = + dyn_cast<llvm::CallInst>(result->stripPointerCasts()); + if (!retainCall || + retainCall->getCalledValue() != CGF.CGM.getObjCEntrypoints().objc_retain) + return nullptr; + + // Look for an ordinary load of 'self'. + llvm::Value *retainedValue = retainCall->getArgOperand(0); + llvm::LoadInst *load = + dyn_cast<llvm::LoadInst>(retainedValue->stripPointerCasts()); + if (!load || load->isAtomic() || load->isVolatile() || + load->getPointerOperand() != CGF.GetAddrOfLocalVar(self).getPointer()) + return nullptr; + + // Okay! Burn it all down. This relies for correctness on the + // assumption that the retain is emitted as part of the return and + // that thereafter everything is used "linearly". + llvm::Type *resultType = result->getType(); + eraseUnusedBitCasts(cast<llvm::Instruction>(result)); + assert(retainCall->use_empty()); + retainCall->eraseFromParent(); + eraseUnusedBitCasts(cast<llvm::Instruction>(retainedValue)); + + return CGF.Builder.CreateBitCast(load, resultType); +} + +/// Emit an ARC autorelease of the result of a function. +/// +/// \return the value to actually return from the function +static llvm::Value *emitAutoreleaseOfResult(CodeGenFunction &CGF, + llvm::Value *result) { + // If we're returning 'self', kill the initial retain. This is a + // heuristic attempt to "encourage correctness" in the really unfortunate + // case where we have a return of self during a dealloc and we desperately + // need to avoid the possible autorelease. + if (llvm::Value *self = tryRemoveRetainOfSelf(CGF, result)) + return self; + + // At -O0, try to emit a fused retain/autorelease. + if (CGF.shouldUseFusedARCCalls()) + if (llvm::Value *fused = tryEmitFusedAutoreleaseOfResult(CGF, result)) + return fused; + + return CGF.EmitARCAutoreleaseReturnValue(result); +} + +/// Heuristically search for a dominating store to the return-value slot. +static llvm::StoreInst *findDominatingStoreToReturnValue(CodeGenFunction &CGF) { + // Check if a User is a store which pointerOperand is the ReturnValue. + // We are looking for stores to the ReturnValue, not for stores of the + // ReturnValue to some other location. + auto GetStoreIfValid = [&CGF](llvm::User *U) -> llvm::StoreInst * { + auto *SI = dyn_cast<llvm::StoreInst>(U); + if (!SI || SI->getPointerOperand() != CGF.ReturnValue.getPointer()) + return nullptr; + // These aren't actually possible for non-coerced returns, and we + // only care about non-coerced returns on this code path. + assert(!SI->isAtomic() && !SI->isVolatile()); + return SI; + }; + // If there are multiple uses of the return-value slot, just check + // for something immediately preceding the IP. Sometimes this can + // happen with how we generate implicit-returns; it can also happen + // with noreturn cleanups. + if (!CGF.ReturnValue.getPointer()->hasOneUse()) { + llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock(); + if (IP->empty()) return nullptr; + llvm::Instruction *I = &IP->back(); + + // Skip lifetime markers + for (llvm::BasicBlock::reverse_iterator II = IP->rbegin(), + IE = IP->rend(); + II != IE; ++II) { + if (llvm::IntrinsicInst *Intrinsic = + dyn_cast<llvm::IntrinsicInst>(&*II)) { + if (Intrinsic->getIntrinsicID() == llvm::Intrinsic::lifetime_end) { + const llvm::Value *CastAddr = Intrinsic->getArgOperand(1); + ++II; + if (II == IE) + break; + if (isa<llvm::BitCastInst>(&*II) && (CastAddr == &*II)) + continue; + } + } + I = &*II; + break; + } + + return GetStoreIfValid(I); + } + + llvm::StoreInst *store = + GetStoreIfValid(CGF.ReturnValue.getPointer()->user_back()); + if (!store) return nullptr; + + // Now do a first-and-dirty dominance check: just walk up the + // single-predecessors chain from the current insertion point. + llvm::BasicBlock *StoreBB = store->getParent(); + llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock(); + while (IP != StoreBB) { + if (!(IP = IP->getSinglePredecessor())) + return nullptr; + } + + // Okay, the store's basic block dominates the insertion point; we + // can do our thing. + return store; +} + +void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI, + bool EmitRetDbgLoc, + SourceLocation EndLoc) { + if (FI.isNoReturn()) { + // Noreturn functions don't return. + EmitUnreachable(EndLoc); + return; + } + + if (CurCodeDecl && CurCodeDecl->hasAttr<NakedAttr>()) { + // Naked functions don't have epilogues. + Builder.CreateUnreachable(); + return; + } + + // Functions with no result always return void. + if (!ReturnValue.isValid()) { + Builder.CreateRetVoid(); + return; + } + + llvm::DebugLoc RetDbgLoc; + llvm::Value *RV = nullptr; + QualType RetTy = FI.getReturnType(); + const ABIArgInfo &RetAI = FI.getReturnInfo(); + + switch (RetAI.getKind()) { + case ABIArgInfo::InAlloca: + // Aggregrates get evaluated directly into the destination. Sometimes we + // need to return the sret value in a register, though. + assert(hasAggregateEvaluationKind(RetTy)); + if (RetAI.getInAllocaSRet()) { + llvm::Function::arg_iterator EI = CurFn->arg_end(); + --EI; + llvm::Value *ArgStruct = &*EI; + llvm::Value *SRet = Builder.CreateStructGEP( + nullptr, ArgStruct, RetAI.getInAllocaFieldIndex()); + RV = Builder.CreateAlignedLoad(SRet, getPointerAlign(), "sret"); + } + break; + + case ABIArgInfo::Indirect: { + auto AI = CurFn->arg_begin(); + if (RetAI.isSRetAfterThis()) + ++AI; + switch (getEvaluationKind(RetTy)) { + case TEK_Complex: { + ComplexPairTy RT = + EmitLoadOfComplex(MakeAddrLValue(ReturnValue, RetTy), EndLoc); + EmitStoreOfComplex(RT, MakeNaturalAlignAddrLValue(&*AI, RetTy), + /*isInit*/ true); + break; + } + case TEK_Aggregate: + // Do nothing; aggregrates get evaluated directly into the destination. + break; + case TEK_Scalar: + EmitStoreOfScalar(Builder.CreateLoad(ReturnValue), + MakeNaturalAlignAddrLValue(&*AI, RetTy), + /*isInit*/ true); + break; + } + break; + } + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: + if (RetAI.getCoerceToType() == ConvertType(RetTy) && + RetAI.getDirectOffset() == 0) { + // The internal return value temp always will have pointer-to-return-type + // type, just do a load. + + // If there is a dominating store to ReturnValue, we can elide + // the load, zap the store, and usually zap the alloca. + if (llvm::StoreInst *SI = + findDominatingStoreToReturnValue(*this)) { + // Reuse the debug location from the store unless there is + // cleanup code to be emitted between the store and return + // instruction. + if (EmitRetDbgLoc && !AutoreleaseResult) + RetDbgLoc = SI->getDebugLoc(); + // Get the stored value and nuke the now-dead store. + RV = SI->getValueOperand(); + SI->eraseFromParent(); + + // Otherwise, we have to do a simple load. + } else { + RV = Builder.CreateLoad(ReturnValue); + } + } else { + // If the value is offset in memory, apply the offset now. + Address V = emitAddressAtOffset(*this, ReturnValue, RetAI); + + RV = CreateCoercedLoad(V, RetAI.getCoerceToType(), *this); + } + + // In ARC, end functions that return a retainable type with a call + // to objc_autoreleaseReturnValue. + if (AutoreleaseResult) { +#ifndef NDEBUG + // Type::isObjCRetainabletype has to be called on a QualType that hasn't + // been stripped of the typedefs, so we cannot use RetTy here. Get the + // original return type of FunctionDecl, CurCodeDecl, and BlockDecl from + // CurCodeDecl or BlockInfo. + QualType RT; + + if (auto *FD = dyn_cast<FunctionDecl>(CurCodeDecl)) + RT = FD->getReturnType(); + else if (auto *MD = dyn_cast<ObjCMethodDecl>(CurCodeDecl)) + RT = MD->getReturnType(); + else if (isa<BlockDecl>(CurCodeDecl)) + RT = BlockInfo->BlockExpression->getFunctionType()->getReturnType(); + else + llvm_unreachable("Unexpected function/method type"); + + assert(getLangOpts().ObjCAutoRefCount && + !FI.isReturnsRetained() && + RT->isObjCRetainableType()); +#endif + RV = emitAutoreleaseOfResult(*this, RV); + } + + break; + + case ABIArgInfo::Ignore: + break; + + case ABIArgInfo::CoerceAndExpand: { + auto coercionType = RetAI.getCoerceAndExpandType(); + + // Load all of the coerced elements out into results. + llvm::SmallVector<llvm::Value*, 4> results; + Address addr = Builder.CreateElementBitCast(ReturnValue, coercionType); + for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) { + auto coercedEltType = coercionType->getElementType(i); + if (ABIArgInfo::isPaddingForCoerceAndExpand(coercedEltType)) + continue; + + auto eltAddr = Builder.CreateStructGEP(addr, i); + auto elt = Builder.CreateLoad(eltAddr); + results.push_back(elt); + } + + // If we have one result, it's the single direct result type. + if (results.size() == 1) { + RV = results[0]; + + // Otherwise, we need to make a first-class aggregate. + } else { + // Construct a return type that lacks padding elements. + llvm::Type *returnType = RetAI.getUnpaddedCoerceAndExpandType(); + + RV = llvm::UndefValue::get(returnType); + for (unsigned i = 0, e = results.size(); i != e; ++i) { + RV = Builder.CreateInsertValue(RV, results[i], i); + } + } + break; + } + + case ABIArgInfo::Expand: + llvm_unreachable("Invalid ABI kind for return argument"); + } + + llvm::Instruction *Ret; + if (RV) { + EmitReturnValueCheck(RV); + Ret = Builder.CreateRet(RV); + } else { + Ret = Builder.CreateRetVoid(); + } + + if (RetDbgLoc) + Ret->setDebugLoc(std::move(RetDbgLoc)); +} + +void CodeGenFunction::EmitReturnValueCheck(llvm::Value *RV) { + // A current decl may not be available when emitting vtable thunks. + if (!CurCodeDecl) + return; + + ReturnsNonNullAttr *RetNNAttr = nullptr; + if (SanOpts.has(SanitizerKind::ReturnsNonnullAttribute)) + RetNNAttr = CurCodeDecl->getAttr<ReturnsNonNullAttr>(); + + if (!RetNNAttr && !requiresReturnValueNullabilityCheck()) + return; + + // Prefer the returns_nonnull attribute if it's present. + SourceLocation AttrLoc; + SanitizerMask CheckKind; + SanitizerHandler Handler; + if (RetNNAttr) { + assert(!requiresReturnValueNullabilityCheck() && + "Cannot check nullability and the nonnull attribute"); + AttrLoc = RetNNAttr->getLocation(); + CheckKind = SanitizerKind::ReturnsNonnullAttribute; + Handler = SanitizerHandler::NonnullReturn; + } else { + if (auto *DD = dyn_cast<DeclaratorDecl>(CurCodeDecl)) + if (auto *TSI = DD->getTypeSourceInfo()) + if (auto FTL = TSI->getTypeLoc().castAs<FunctionTypeLoc>()) + AttrLoc = FTL.getReturnLoc().findNullabilityLoc(); + CheckKind = SanitizerKind::NullabilityReturn; + Handler = SanitizerHandler::NullabilityReturn; + } + + SanitizerScope SanScope(this); + + // Make sure the "return" source location is valid. If we're checking a + // nullability annotation, make sure the preconditions for the check are met. + llvm::BasicBlock *Check = createBasicBlock("nullcheck"); + llvm::BasicBlock *NoCheck = createBasicBlock("no.nullcheck"); + llvm::Value *SLocPtr = Builder.CreateLoad(ReturnLocation, "return.sloc.load"); + llvm::Value *CanNullCheck = Builder.CreateIsNotNull(SLocPtr); + if (requiresReturnValueNullabilityCheck()) + CanNullCheck = + Builder.CreateAnd(CanNullCheck, RetValNullabilityPrecondition); + Builder.CreateCondBr(CanNullCheck, Check, NoCheck); + EmitBlock(Check); + + // Now do the null check. + llvm::Value *Cond = Builder.CreateIsNotNull(RV); + llvm::Constant *StaticData[] = {EmitCheckSourceLocation(AttrLoc)}; + llvm::Value *DynamicData[] = {SLocPtr}; + EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, DynamicData); + + EmitBlock(NoCheck); + +#ifndef NDEBUG + // The return location should not be used after the check has been emitted. + ReturnLocation = Address::invalid(); +#endif +} + +static bool isInAllocaArgument(CGCXXABI &ABI, QualType type) { + const CXXRecordDecl *RD = type->getAsCXXRecordDecl(); + return RD && ABI.getRecordArgABI(RD) == CGCXXABI::RAA_DirectInMemory; +} + +static AggValueSlot createPlaceholderSlot(CodeGenFunction &CGF, + QualType Ty) { + // FIXME: Generate IR in one pass, rather than going back and fixing up these + // placeholders. + llvm::Type *IRTy = CGF.ConvertTypeForMem(Ty); + llvm::Type *IRPtrTy = IRTy->getPointerTo(); + llvm::Value *Placeholder = llvm::UndefValue::get(IRPtrTy->getPointerTo()); + + // FIXME: When we generate this IR in one pass, we shouldn't need + // this win32-specific alignment hack. + CharUnits Align = CharUnits::fromQuantity(4); + Placeholder = CGF.Builder.CreateAlignedLoad(IRPtrTy, Placeholder, Align); + + return AggValueSlot::forAddr(Address(Placeholder, Align), + Ty.getQualifiers(), + AggValueSlot::IsNotDestructed, + AggValueSlot::DoesNotNeedGCBarriers, + AggValueSlot::IsNotAliased, + AggValueSlot::DoesNotOverlap); +} + +void CodeGenFunction::EmitDelegateCallArg(CallArgList &args, + const VarDecl *param, + SourceLocation loc) { + // StartFunction converted the ABI-lowered parameter(s) into a + // local alloca. We need to turn that into an r-value suitable + // for EmitCall. + Address local = GetAddrOfLocalVar(param); + + QualType type = param->getType(); + + if (isInAllocaArgument(CGM.getCXXABI(), type)) { + CGM.ErrorUnsupported(param, "forwarded non-trivially copyable parameter"); + } + + // GetAddrOfLocalVar returns a pointer-to-pointer for references, + // but the argument needs to be the original pointer. + if (type->isReferenceType()) { + args.add(RValue::get(Builder.CreateLoad(local)), type); + + // In ARC, move out of consumed arguments so that the release cleanup + // entered by StartFunction doesn't cause an over-release. This isn't + // optimal -O0 code generation, but it should get cleaned up when + // optimization is enabled. This also assumes that delegate calls are + // performed exactly once for a set of arguments, but that should be safe. + } else if (getLangOpts().ObjCAutoRefCount && + param->hasAttr<NSConsumedAttr>() && + type->isObjCRetainableType()) { + llvm::Value *ptr = Builder.CreateLoad(local); + auto null = + llvm::ConstantPointerNull::get(cast<llvm::PointerType>(ptr->getType())); + Builder.CreateStore(null, local); + args.add(RValue::get(ptr), type); + + // For the most part, we just need to load the alloca, except that + // aggregate r-values are actually pointers to temporaries. + } else { + args.add(convertTempToRValue(local, type, loc), type); + } + + // Deactivate the cleanup for the callee-destructed param that was pushed. + if (hasAggregateEvaluationKind(type) && !CurFuncIsThunk && + type->castAs<RecordType>()->getDecl()->isParamDestroyedInCallee() && + param->needsDestruction(getContext())) { + EHScopeStack::stable_iterator cleanup = + CalleeDestructedParamCleanups.lookup(cast<ParmVarDecl>(param)); + assert(cleanup.isValid() && + "cleanup for callee-destructed param not recorded"); + // This unreachable is a temporary marker which will be removed later. + llvm::Instruction *isActive = Builder.CreateUnreachable(); + args.addArgCleanupDeactivation(cleanup, isActive); + } +} + +static bool isProvablyNull(llvm::Value *addr) { + return isa<llvm::ConstantPointerNull>(addr); +} + +/// Emit the actual writing-back of a writeback. +static void emitWriteback(CodeGenFunction &CGF, + const CallArgList::Writeback &writeback) { + const LValue &srcLV = writeback.Source; + Address srcAddr = srcLV.getAddress(); + assert(!isProvablyNull(srcAddr.getPointer()) && + "shouldn't have writeback for provably null argument"); + + llvm::BasicBlock *contBB = nullptr; + + // If the argument wasn't provably non-null, we need to null check + // before doing the store. + bool provablyNonNull = llvm::isKnownNonZero(srcAddr.getPointer(), + CGF.CGM.getDataLayout()); + if (!provablyNonNull) { + llvm::BasicBlock *writebackBB = CGF.createBasicBlock("icr.writeback"); + contBB = CGF.createBasicBlock("icr.done"); + + llvm::Value *isNull = + CGF.Builder.CreateIsNull(srcAddr.getPointer(), "icr.isnull"); + CGF.Builder.CreateCondBr(isNull, contBB, writebackBB); + CGF.EmitBlock(writebackBB); + } + + // Load the value to writeback. + llvm::Value *value = CGF.Builder.CreateLoad(writeback.Temporary); + + // Cast it back, in case we're writing an id to a Foo* or something. + value = CGF.Builder.CreateBitCast(value, srcAddr.getElementType(), + "icr.writeback-cast"); + + // Perform the writeback. + + // If we have a "to use" value, it's something we need to emit a use + // of. This has to be carefully threaded in: if it's done after the + // release it's potentially undefined behavior (and the optimizer + // will ignore it), and if it happens before the retain then the + // optimizer could move the release there. + if (writeback.ToUse) { + assert(srcLV.getObjCLifetime() == Qualifiers::OCL_Strong); + + // Retain the new value. No need to block-copy here: the block's + // being passed up the stack. + value = CGF.EmitARCRetainNonBlock(value); + + // Emit the intrinsic use here. + CGF.EmitARCIntrinsicUse(writeback.ToUse); + + // Load the old value (primitively). + llvm::Value *oldValue = CGF.EmitLoadOfScalar(srcLV, SourceLocation()); + + // Put the new value in place (primitively). + CGF.EmitStoreOfScalar(value, srcLV, /*init*/ false); + + // Release the old value. + CGF.EmitARCRelease(oldValue, srcLV.isARCPreciseLifetime()); + + // Otherwise, we can just do a normal lvalue store. + } else { + CGF.EmitStoreThroughLValue(RValue::get(value), srcLV); + } + + // Jump to the continuation block. + if (!provablyNonNull) + CGF.EmitBlock(contBB); +} + +static void emitWritebacks(CodeGenFunction &CGF, + const CallArgList &args) { + for (const auto &I : args.writebacks()) + emitWriteback(CGF, I); +} + +static void deactivateArgCleanupsBeforeCall(CodeGenFunction &CGF, + const CallArgList &CallArgs) { + ArrayRef<CallArgList::CallArgCleanup> Cleanups = + CallArgs.getCleanupsToDeactivate(); + // Iterate in reverse to increase the likelihood of popping the cleanup. + for (const auto &I : llvm::reverse(Cleanups)) { + CGF.DeactivateCleanupBlock(I.Cleanup, I.IsActiveIP); + I.IsActiveIP->eraseFromParent(); + } +} + +static const Expr *maybeGetUnaryAddrOfOperand(const Expr *E) { + if (const UnaryOperator *uop = dyn_cast<UnaryOperator>(E->IgnoreParens())) + if (uop->getOpcode() == UO_AddrOf) + return uop->getSubExpr(); + return nullptr; +} + +/// Emit an argument that's being passed call-by-writeback. That is, +/// we are passing the address of an __autoreleased temporary; it +/// might be copy-initialized with the current value of the given +/// address, but it will definitely be copied out of after the call. +static void emitWritebackArg(CodeGenFunction &CGF, CallArgList &args, + const ObjCIndirectCopyRestoreExpr *CRE) { + LValue srcLV; + + // Make an optimistic effort to emit the address as an l-value. + // This can fail if the argument expression is more complicated. + if (const Expr *lvExpr = maybeGetUnaryAddrOfOperand(CRE->getSubExpr())) { + srcLV = CGF.EmitLValue(lvExpr); + + // Otherwise, just emit it as a scalar. + } else { + Address srcAddr = CGF.EmitPointerWithAlignment(CRE->getSubExpr()); + + QualType srcAddrType = + CRE->getSubExpr()->getType()->castAs<PointerType>()->getPointeeType(); + srcLV = CGF.MakeAddrLValue(srcAddr, srcAddrType); + } + Address srcAddr = srcLV.getAddress(); + + // The dest and src types don't necessarily match in LLVM terms + // because of the crazy ObjC compatibility rules. + + llvm::PointerType *destType = + cast<llvm::PointerType>(CGF.ConvertType(CRE->getType())); + + // If the address is a constant null, just pass the appropriate null. + if (isProvablyNull(srcAddr.getPointer())) { + args.add(RValue::get(llvm::ConstantPointerNull::get(destType)), + CRE->getType()); + return; + } + + // Create the temporary. + Address temp = CGF.CreateTempAlloca(destType->getElementType(), + CGF.getPointerAlign(), + "icr.temp"); + // Loading an l-value can introduce a cleanup if the l-value is __weak, + // and that cleanup will be conditional if we can't prove that the l-value + // isn't null, so we need to register a dominating point so that the cleanups + // system will make valid IR. + CodeGenFunction::ConditionalEvaluation condEval(CGF); + + // Zero-initialize it if we're not doing a copy-initialization. + bool shouldCopy = CRE->shouldCopy(); + if (!shouldCopy) { + llvm::Value *null = + llvm::ConstantPointerNull::get( + cast<llvm::PointerType>(destType->getElementType())); + CGF.Builder.CreateStore(null, temp); + } + + llvm::BasicBlock *contBB = nullptr; + llvm::BasicBlock *originBB = nullptr; + + // If the address is *not* known to be non-null, we need to switch. + llvm::Value *finalArgument; + + bool provablyNonNull = llvm::isKnownNonZero(srcAddr.getPointer(), + CGF.CGM.getDataLayout()); + if (provablyNonNull) { + finalArgument = temp.getPointer(); + } else { + llvm::Value *isNull = + CGF.Builder.CreateIsNull(srcAddr.getPointer(), "icr.isnull"); + + finalArgument = CGF.Builder.CreateSelect(isNull, + llvm::ConstantPointerNull::get(destType), + temp.getPointer(), "icr.argument"); + + // If we need to copy, then the load has to be conditional, which + // means we need control flow. + if (shouldCopy) { + originBB = CGF.Builder.GetInsertBlock(); + contBB = CGF.createBasicBlock("icr.cont"); + llvm::BasicBlock *copyBB = CGF.createBasicBlock("icr.copy"); + CGF.Builder.CreateCondBr(isNull, contBB, copyBB); + CGF.EmitBlock(copyBB); + condEval.begin(CGF); + } + } + + llvm::Value *valueToUse = nullptr; + + // Perform a copy if necessary. + if (shouldCopy) { + RValue srcRV = CGF.EmitLoadOfLValue(srcLV, SourceLocation()); + assert(srcRV.isScalar()); + + llvm::Value *src = srcRV.getScalarVal(); + src = CGF.Builder.CreateBitCast(src, destType->getElementType(), + "icr.cast"); + + // Use an ordinary store, not a store-to-lvalue. + CGF.Builder.CreateStore(src, temp); + + // If optimization is enabled, and the value was held in a + // __strong variable, we need to tell the optimizer that this + // value has to stay alive until we're doing the store back. + // This is because the temporary is effectively unretained, + // and so otherwise we can violate the high-level semantics. + if (CGF.CGM.getCodeGenOpts().OptimizationLevel != 0 && + srcLV.getObjCLifetime() == Qualifiers::OCL_Strong) { + valueToUse = src; + } + } + + // Finish the control flow if we needed it. + if (shouldCopy && !provablyNonNull) { + llvm::BasicBlock *copyBB = CGF.Builder.GetInsertBlock(); + CGF.EmitBlock(contBB); + + // Make a phi for the value to intrinsically use. + if (valueToUse) { + llvm::PHINode *phiToUse = CGF.Builder.CreatePHI(valueToUse->getType(), 2, + "icr.to-use"); + phiToUse->addIncoming(valueToUse, copyBB); + phiToUse->addIncoming(llvm::UndefValue::get(valueToUse->getType()), + originBB); + valueToUse = phiToUse; + } + + condEval.end(CGF); + } + + args.addWriteback(srcLV, temp, valueToUse); + args.add(RValue::get(finalArgument), CRE->getType()); +} + +void CallArgList::allocateArgumentMemory(CodeGenFunction &CGF) { + assert(!StackBase); + + // Save the stack. + llvm::Function *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stacksave); + StackBase = CGF.Builder.CreateCall(F, {}, "inalloca.save"); +} + +void CallArgList::freeArgumentMemory(CodeGenFunction &CGF) const { + if (StackBase) { + // Restore the stack after the call. + llvm::Function *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore); + CGF.Builder.CreateCall(F, StackBase); + } +} + +void CodeGenFunction::EmitNonNullArgCheck(RValue RV, QualType ArgType, + SourceLocation ArgLoc, + AbstractCallee AC, + unsigned ParmNum) { + if (!AC.getDecl() || !(SanOpts.has(SanitizerKind::NonnullAttribute) || + SanOpts.has(SanitizerKind::NullabilityArg))) + return; + + // The param decl may be missing in a variadic function. + auto PVD = ParmNum < AC.getNumParams() ? AC.getParamDecl(ParmNum) : nullptr; + unsigned ArgNo = PVD ? PVD->getFunctionScopeIndex() : ParmNum; + + // Prefer the nonnull attribute if it's present. + const NonNullAttr *NNAttr = nullptr; + if (SanOpts.has(SanitizerKind::NonnullAttribute)) + NNAttr = getNonNullAttr(AC.getDecl(), PVD, ArgType, ArgNo); + + bool CanCheckNullability = false; + if (SanOpts.has(SanitizerKind::NullabilityArg) && !NNAttr && PVD) { + auto Nullability = PVD->getType()->getNullability(getContext()); + CanCheckNullability = Nullability && + *Nullability == NullabilityKind::NonNull && + PVD->getTypeSourceInfo(); + } + + if (!NNAttr && !CanCheckNullability) + return; + + SourceLocation AttrLoc; + SanitizerMask CheckKind; + SanitizerHandler Handler; + if (NNAttr) { + AttrLoc = NNAttr->getLocation(); + CheckKind = SanitizerKind::NonnullAttribute; + Handler = SanitizerHandler::NonnullArg; + } else { + AttrLoc = PVD->getTypeSourceInfo()->getTypeLoc().findNullabilityLoc(); + CheckKind = SanitizerKind::NullabilityArg; + Handler = SanitizerHandler::NullabilityArg; + } + + SanitizerScope SanScope(this); + assert(RV.isScalar()); + llvm::Value *V = RV.getScalarVal(); + llvm::Value *Cond = + Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType())); + llvm::Constant *StaticData[] = { + EmitCheckSourceLocation(ArgLoc), EmitCheckSourceLocation(AttrLoc), + llvm::ConstantInt::get(Int32Ty, ArgNo + 1), + }; + EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, None); +} + +void CodeGenFunction::EmitCallArgs( + CallArgList &Args, ArrayRef<QualType> ArgTypes, + llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange, + AbstractCallee AC, unsigned ParamsToSkip, EvaluationOrder Order) { + assert((int)ArgTypes.size() == (ArgRange.end() - ArgRange.begin())); + + // We *have* to evaluate arguments from right to left in the MS C++ ABI, + // because arguments are destroyed left to right in the callee. As a special + // case, there are certain language constructs that require left-to-right + // evaluation, and in those cases we consider the evaluation order requirement + // to trump the "destruction order is reverse construction order" guarantee. + bool LeftToRight = + CGM.getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee() + ? Order == EvaluationOrder::ForceLeftToRight + : Order != EvaluationOrder::ForceRightToLeft; + + auto MaybeEmitImplicitObjectSize = [&](unsigned I, const Expr *Arg, + RValue EmittedArg) { + if (!AC.hasFunctionDecl() || I >= AC.getNumParams()) + return; + auto *PS = AC.getParamDecl(I)->getAttr<PassObjectSizeAttr>(); + if (PS == nullptr) + return; + + const auto &Context = getContext(); + auto SizeTy = Context.getSizeType(); + auto T = Builder.getIntNTy(Context.getTypeSize(SizeTy)); + assert(EmittedArg.getScalarVal() && "We emitted nothing for the arg?"); + llvm::Value *V = evaluateOrEmitBuiltinObjectSize(Arg, PS->getType(), T, + EmittedArg.getScalarVal(), + PS->isDynamic()); + Args.add(RValue::get(V), SizeTy); + // If we're emitting args in reverse, be sure to do so with + // pass_object_size, as well. + if (!LeftToRight) + std::swap(Args.back(), *(&Args.back() - 1)); + }; + + // Insert a stack save if we're going to need any inalloca args. + bool HasInAllocaArgs = false; + if (CGM.getTarget().getCXXABI().isMicrosoft()) { + for (ArrayRef<QualType>::iterator I = ArgTypes.begin(), E = ArgTypes.end(); + I != E && !HasInAllocaArgs; ++I) + HasInAllocaArgs = isInAllocaArgument(CGM.getCXXABI(), *I); + if (HasInAllocaArgs) { + assert(getTarget().getTriple().getArch() == llvm::Triple::x86); + Args.allocateArgumentMemory(*this); + } + } + + // Evaluate each argument in the appropriate order. + size_t CallArgsStart = Args.size(); + for (unsigned I = 0, E = ArgTypes.size(); I != E; ++I) { + unsigned Idx = LeftToRight ? I : E - I - 1; + CallExpr::const_arg_iterator Arg = ArgRange.begin() + Idx; + unsigned InitialArgSize = Args.size(); + // If *Arg is an ObjCIndirectCopyRestoreExpr, check that either the types of + // the argument and parameter match or the objc method is parameterized. + assert((!isa<ObjCIndirectCopyRestoreExpr>(*Arg) || + getContext().hasSameUnqualifiedType((*Arg)->getType(), + ArgTypes[Idx]) || + (isa<ObjCMethodDecl>(AC.getDecl()) && + isObjCMethodWithTypeParams(cast<ObjCMethodDecl>(AC.getDecl())))) && + "Argument and parameter types don't match"); + EmitCallArg(Args, *Arg, ArgTypes[Idx]); + // In particular, we depend on it being the last arg in Args, and the + // objectsize bits depend on there only being one arg if !LeftToRight. + assert(InitialArgSize + 1 == Args.size() && + "The code below depends on only adding one arg per EmitCallArg"); + (void)InitialArgSize; + // Since pointer argument are never emitted as LValue, it is safe to emit + // non-null argument check for r-value only. + if (!Args.back().hasLValue()) { + RValue RVArg = Args.back().getKnownRValue(); + EmitNonNullArgCheck(RVArg, ArgTypes[Idx], (*Arg)->getExprLoc(), AC, + ParamsToSkip + Idx); + // @llvm.objectsize should never have side-effects and shouldn't need + // destruction/cleanups, so we can safely "emit" it after its arg, + // regardless of right-to-leftness + MaybeEmitImplicitObjectSize(Idx, *Arg, RVArg); + } + } + + if (!LeftToRight) { + // Un-reverse the arguments we just evaluated so they match up with the LLVM + // IR function. + std::reverse(Args.begin() + CallArgsStart, Args.end()); + } +} + +namespace { + +struct DestroyUnpassedArg final : EHScopeStack::Cleanup { + DestroyUnpassedArg(Address Addr, QualType Ty) + : Addr(Addr), Ty(Ty) {} + + Address Addr; + QualType Ty; + + void Emit(CodeGenFunction &CGF, Flags flags) override { + QualType::DestructionKind DtorKind = Ty.isDestructedType(); + if (DtorKind == QualType::DK_cxx_destructor) { + const CXXDestructorDecl *Dtor = Ty->getAsCXXRecordDecl()->getDestructor(); + assert(!Dtor->isTrivial()); + CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete, /*for vbase*/ false, + /*Delegating=*/false, Addr, Ty); + } else { + CGF.callCStructDestructor(CGF.MakeAddrLValue(Addr, Ty)); + } + } +}; + +struct DisableDebugLocationUpdates { + CodeGenFunction &CGF; + bool disabledDebugInfo; + DisableDebugLocationUpdates(CodeGenFunction &CGF, const Expr *E) : CGF(CGF) { + if ((disabledDebugInfo = isa<CXXDefaultArgExpr>(E) && CGF.getDebugInfo())) + CGF.disableDebugInfo(); + } + ~DisableDebugLocationUpdates() { + if (disabledDebugInfo) + CGF.enableDebugInfo(); + } +}; + +} // end anonymous namespace + +RValue CallArg::getRValue(CodeGenFunction &CGF) const { + if (!HasLV) + return RV; + LValue Copy = CGF.MakeAddrLValue(CGF.CreateMemTemp(Ty), Ty); + CGF.EmitAggregateCopy(Copy, LV, Ty, AggValueSlot::DoesNotOverlap, + LV.isVolatile()); + IsUsed = true; + return RValue::getAggregate(Copy.getAddress()); +} + +void CallArg::copyInto(CodeGenFunction &CGF, Address Addr) const { + LValue Dst = CGF.MakeAddrLValue(Addr, Ty); + if (!HasLV && RV.isScalar()) + CGF.EmitStoreOfScalar(RV.getScalarVal(), Dst, /*isInit=*/true); + else if (!HasLV && RV.isComplex()) + CGF.EmitStoreOfComplex(RV.getComplexVal(), Dst, /*init=*/true); + else { + auto Addr = HasLV ? LV.getAddress() : RV.getAggregateAddress(); + LValue SrcLV = CGF.MakeAddrLValue(Addr, Ty); + // We assume that call args are never copied into subobjects. + CGF.EmitAggregateCopy(Dst, SrcLV, Ty, AggValueSlot::DoesNotOverlap, + HasLV ? LV.isVolatileQualified() + : RV.isVolatileQualified()); + } + IsUsed = true; +} + +void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E, + QualType type) { + DisableDebugLocationUpdates Dis(*this, E); + if (const ObjCIndirectCopyRestoreExpr *CRE + = dyn_cast<ObjCIndirectCopyRestoreExpr>(E)) { + assert(getLangOpts().ObjCAutoRefCount); + return emitWritebackArg(*this, args, CRE); + } + + assert(type->isReferenceType() == E->isGLValue() && + "reference binding to unmaterialized r-value!"); + + if (E->isGLValue()) { + assert(E->getObjectKind() == OK_Ordinary); + return args.add(EmitReferenceBindingToExpr(E), type); + } + + bool HasAggregateEvalKind = hasAggregateEvaluationKind(type); + + // In the Microsoft C++ ABI, aggregate arguments are destructed by the callee. + // However, we still have to push an EH-only cleanup in case we unwind before + // we make it to the call. + if (HasAggregateEvalKind && + type->castAs<RecordType>()->getDecl()->isParamDestroyedInCallee()) { + // If we're using inalloca, use the argument memory. Otherwise, use a + // temporary. + AggValueSlot Slot; + if (args.isUsingInAlloca()) + Slot = createPlaceholderSlot(*this, type); + else + Slot = CreateAggTemp(type, "agg.tmp"); + + bool DestroyedInCallee = true, NeedsEHCleanup = true; + if (const auto *RD = type->getAsCXXRecordDecl()) + DestroyedInCallee = RD->hasNonTrivialDestructor(); + else + NeedsEHCleanup = needsEHCleanup(type.isDestructedType()); + + if (DestroyedInCallee) + Slot.setExternallyDestructed(); + + EmitAggExpr(E, Slot); + RValue RV = Slot.asRValue(); + args.add(RV, type); + + if (DestroyedInCallee && NeedsEHCleanup) { + // Create a no-op GEP between the placeholder and the cleanup so we can + // RAUW it successfully. It also serves as a marker of the first + // instruction where the cleanup is active. + pushFullExprCleanup<DestroyUnpassedArg>(EHCleanup, Slot.getAddress(), + type); + // This unreachable is a temporary marker which will be removed later. + llvm::Instruction *IsActive = Builder.CreateUnreachable(); + args.addArgCleanupDeactivation(EHStack.getInnermostEHScope(), IsActive); + } + return; + } + + if (HasAggregateEvalKind && isa<ImplicitCastExpr>(E) && + cast<CastExpr>(E)->getCastKind() == CK_LValueToRValue) { + LValue L = EmitLValue(cast<CastExpr>(E)->getSubExpr()); + assert(L.isSimple()); + args.addUncopiedAggregate(L, type); + return; + } + + args.add(EmitAnyExprToTemp(E), type); +} + +QualType CodeGenFunction::getVarArgType(const Expr *Arg) { + // System headers on Windows define NULL to 0 instead of 0LL on Win64. MSVC + // implicitly widens null pointer constants that are arguments to varargs + // functions to pointer-sized ints. + if (!getTarget().getTriple().isOSWindows()) + return Arg->getType(); + + if (Arg->getType()->isIntegerType() && + getContext().getTypeSize(Arg->getType()) < + getContext().getTargetInfo().getPointerWidth(0) && + Arg->isNullPointerConstant(getContext(), + Expr::NPC_ValueDependentIsNotNull)) { + return getContext().getIntPtrType(); + } + + return Arg->getType(); +} + +// In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC +// optimizer it can aggressively ignore unwind edges. +void +CodeGenFunction::AddObjCARCExceptionMetadata(llvm::Instruction *Inst) { + if (CGM.getCodeGenOpts().OptimizationLevel != 0 && + !CGM.getCodeGenOpts().ObjCAutoRefCountExceptions) + Inst->setMetadata("clang.arc.no_objc_arc_exceptions", + CGM.getNoObjCARCExceptionsMetadata()); +} + +/// Emits a call to the given no-arguments nounwind runtime function. +llvm::CallInst * +CodeGenFunction::EmitNounwindRuntimeCall(llvm::FunctionCallee callee, + const llvm::Twine &name) { + return EmitNounwindRuntimeCall(callee, None, name); +} + +/// Emits a call to the given nounwind runtime function. +llvm::CallInst * +CodeGenFunction::EmitNounwindRuntimeCall(llvm::FunctionCallee callee, + ArrayRef<llvm::Value *> args, + const llvm::Twine &name) { + llvm::CallInst *call = EmitRuntimeCall(callee, args, name); + call->setDoesNotThrow(); + return call; +} + +/// Emits a simple call (never an invoke) to the given no-arguments +/// runtime function. +llvm::CallInst *CodeGenFunction::EmitRuntimeCall(llvm::FunctionCallee callee, + const llvm::Twine &name) { + return EmitRuntimeCall(callee, None, name); +} + +// Calls which may throw must have operand bundles indicating which funclet +// they are nested within. +SmallVector<llvm::OperandBundleDef, 1> +CodeGenFunction::getBundlesForFunclet(llvm::Value *Callee) { + SmallVector<llvm::OperandBundleDef, 1> BundleList; + // There is no need for a funclet operand bundle if we aren't inside a + // funclet. + if (!CurrentFuncletPad) + return BundleList; + + // Skip intrinsics which cannot throw. + auto *CalleeFn = dyn_cast<llvm::Function>(Callee->stripPointerCasts()); + if (CalleeFn && CalleeFn->isIntrinsic() && CalleeFn->doesNotThrow()) + return BundleList; + + BundleList.emplace_back("funclet", CurrentFuncletPad); + return BundleList; +} + +/// Emits a simple call (never an invoke) to the given runtime function. +llvm::CallInst *CodeGenFunction::EmitRuntimeCall(llvm::FunctionCallee callee, + ArrayRef<llvm::Value *> args, + const llvm::Twine &name) { + llvm::CallInst *call = Builder.CreateCall( + callee, args, getBundlesForFunclet(callee.getCallee()), name); + call->setCallingConv(getRuntimeCC()); + return call; +} + +/// Emits a call or invoke to the given noreturn runtime function. +void CodeGenFunction::EmitNoreturnRuntimeCallOrInvoke( + llvm::FunctionCallee callee, ArrayRef<llvm::Value *> args) { + SmallVector<llvm::OperandBundleDef, 1> BundleList = + getBundlesForFunclet(callee.getCallee()); + + if (getInvokeDest()) { + llvm::InvokeInst *invoke = + Builder.CreateInvoke(callee, + getUnreachableBlock(), + getInvokeDest(), + args, + BundleList); + invoke->setDoesNotReturn(); + invoke->setCallingConv(getRuntimeCC()); + } else { + llvm::CallInst *call = Builder.CreateCall(callee, args, BundleList); + call->setDoesNotReturn(); + call->setCallingConv(getRuntimeCC()); + Builder.CreateUnreachable(); + } +} + +/// Emits a call or invoke instruction to the given nullary runtime function. +llvm::CallBase * +CodeGenFunction::EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee, + const Twine &name) { + return EmitRuntimeCallOrInvoke(callee, None, name); +} + +/// Emits a call or invoke instruction to the given runtime function. +llvm::CallBase * +CodeGenFunction::EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee, + ArrayRef<llvm::Value *> args, + const Twine &name) { + llvm::CallBase *call = EmitCallOrInvoke(callee, args, name); + call->setCallingConv(getRuntimeCC()); + return call; +} + +/// Emits a call or invoke instruction to the given function, depending +/// on the current state of the EH stack. +llvm::CallBase *CodeGenFunction::EmitCallOrInvoke(llvm::FunctionCallee Callee, + ArrayRef<llvm::Value *> Args, + const Twine &Name) { + llvm::BasicBlock *InvokeDest = getInvokeDest(); + SmallVector<llvm::OperandBundleDef, 1> BundleList = + getBundlesForFunclet(Callee.getCallee()); + + llvm::CallBase *Inst; + if (!InvokeDest) + Inst = Builder.CreateCall(Callee, Args, BundleList, Name); + else { + llvm::BasicBlock *ContBB = createBasicBlock("invoke.cont"); + Inst = Builder.CreateInvoke(Callee, ContBB, InvokeDest, Args, BundleList, + Name); + EmitBlock(ContBB); + } + + // In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC + // optimizer it can aggressively ignore unwind edges. + if (CGM.getLangOpts().ObjCAutoRefCount) + AddObjCARCExceptionMetadata(Inst); + + return Inst; +} + +void CodeGenFunction::deferPlaceholderReplacement(llvm::Instruction *Old, + llvm::Value *New) { + DeferredReplacements.push_back(std::make_pair(Old, New)); +} + +RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo, + const CGCallee &Callee, + ReturnValueSlot ReturnValue, + const CallArgList &CallArgs, + llvm::CallBase **callOrInvoke, + SourceLocation Loc) { + // FIXME: We no longer need the types from CallArgs; lift up and simplify. + + assert(Callee.isOrdinary() || Callee.isVirtual()); + + // Handle struct-return functions by passing a pointer to the + // location that we would like to return into. + QualType RetTy = CallInfo.getReturnType(); + const ABIArgInfo &RetAI = CallInfo.getReturnInfo(); + + llvm::FunctionType *IRFuncTy = getTypes().GetFunctionType(CallInfo); + + const Decl *TargetDecl = Callee.getAbstractInfo().getCalleeDecl().getDecl(); + if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) + // We can only guarantee that a function is called from the correct + // context/function based on the appropriate target attributes, + // so only check in the case where we have both always_inline and target + // since otherwise we could be making a conditional call after a check for + // the proper cpu features (and it won't cause code generation issues due to + // function based code generation). + if (TargetDecl->hasAttr<AlwaysInlineAttr>() && + TargetDecl->hasAttr<TargetAttr>()) + checkTargetFeatures(Loc, FD); + +#ifndef NDEBUG + if (!(CallInfo.isVariadic() && CallInfo.getArgStruct())) { + // For an inalloca varargs function, we don't expect CallInfo to match the + // function pointer's type, because the inalloca struct a will have extra + // fields in it for the varargs parameters. Code later in this function + // bitcasts the function pointer to the type derived from CallInfo. + // + // In other cases, we assert that the types match up (until pointers stop + // having pointee types). + llvm::Type *TypeFromVal; + if (Callee.isVirtual()) + TypeFromVal = Callee.getVirtualFunctionType(); + else + TypeFromVal = + Callee.getFunctionPointer()->getType()->getPointerElementType(); + assert(IRFuncTy == TypeFromVal); + } +#endif + + // 1. Set up the arguments. + + // If we're using inalloca, insert the allocation after the stack save. + // FIXME: Do this earlier rather than hacking it in here! + Address ArgMemory = Address::invalid(); + if (llvm::StructType *ArgStruct = CallInfo.getArgStruct()) { + const llvm::DataLayout &DL = CGM.getDataLayout(); + llvm::Instruction *IP = CallArgs.getStackBase(); + llvm::AllocaInst *AI; + if (IP) { + IP = IP->getNextNode(); + AI = new llvm::AllocaInst(ArgStruct, DL.getAllocaAddrSpace(), + "argmem", IP); + } else { + AI = CreateTempAlloca(ArgStruct, "argmem"); + } + auto Align = CallInfo.getArgStructAlignment(); + AI->setAlignment(Align.getAsAlign()); + AI->setUsedWithInAlloca(true); + assert(AI->isUsedWithInAlloca() && !AI->isStaticAlloca()); + ArgMemory = Address(AI, Align); + } + + ClangToLLVMArgMapping IRFunctionArgs(CGM.getContext(), CallInfo); + SmallVector<llvm::Value *, 16> IRCallArgs(IRFunctionArgs.totalIRArgs()); + + // If the call returns a temporary with struct return, create a temporary + // alloca to hold the result, unless one is given to us. + Address SRetPtr = Address::invalid(); + Address SRetAlloca = Address::invalid(); + llvm::Value *UnusedReturnSizePtr = nullptr; + if (RetAI.isIndirect() || RetAI.isInAlloca() || RetAI.isCoerceAndExpand()) { + if (!ReturnValue.isNull()) { + SRetPtr = ReturnValue.getValue(); + } else { + SRetPtr = CreateMemTemp(RetTy, "tmp", &SRetAlloca); + if (HaveInsertPoint() && ReturnValue.isUnused()) { + uint64_t size = + CGM.getDataLayout().getTypeAllocSize(ConvertTypeForMem(RetTy)); + UnusedReturnSizePtr = EmitLifetimeStart(size, SRetAlloca.getPointer()); + } + } + if (IRFunctionArgs.hasSRetArg()) { + IRCallArgs[IRFunctionArgs.getSRetArgNo()] = SRetPtr.getPointer(); + } else if (RetAI.isInAlloca()) { + Address Addr = + Builder.CreateStructGEP(ArgMemory, RetAI.getInAllocaFieldIndex()); + Builder.CreateStore(SRetPtr.getPointer(), Addr); + } + } + + Address swiftErrorTemp = Address::invalid(); + Address swiftErrorArg = Address::invalid(); + + // When passing arguments using temporary allocas, we need to add the + // appropriate lifetime markers. This vector keeps track of all the lifetime + // markers that need to be ended right after the call. + SmallVector<CallLifetimeEnd, 2> CallLifetimeEndAfterCall; + + // Translate all of the arguments as necessary to match the IR lowering. + assert(CallInfo.arg_size() == CallArgs.size() && + "Mismatch between function signature & arguments."); + unsigned ArgNo = 0; + CGFunctionInfo::const_arg_iterator info_it = CallInfo.arg_begin(); + for (CallArgList::const_iterator I = CallArgs.begin(), E = CallArgs.end(); + I != E; ++I, ++info_it, ++ArgNo) { + const ABIArgInfo &ArgInfo = info_it->info; + + // Insert a padding argument to ensure proper alignment. + if (IRFunctionArgs.hasPaddingArg(ArgNo)) + IRCallArgs[IRFunctionArgs.getPaddingArgNo(ArgNo)] = + llvm::UndefValue::get(ArgInfo.getPaddingType()); + + unsigned FirstIRArg, NumIRArgs; + std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo); + + switch (ArgInfo.getKind()) { + case ABIArgInfo::InAlloca: { + assert(NumIRArgs == 0); + assert(getTarget().getTriple().getArch() == llvm::Triple::x86); + if (I->isAggregate()) { + // Replace the placeholder with the appropriate argument slot GEP. + Address Addr = I->hasLValue() + ? I->getKnownLValue().getAddress() + : I->getKnownRValue().getAggregateAddress(); + llvm::Instruction *Placeholder = + cast<llvm::Instruction>(Addr.getPointer()); + CGBuilderTy::InsertPoint IP = Builder.saveIP(); + Builder.SetInsertPoint(Placeholder); + Addr = + Builder.CreateStructGEP(ArgMemory, ArgInfo.getInAllocaFieldIndex()); + Builder.restoreIP(IP); + deferPlaceholderReplacement(Placeholder, Addr.getPointer()); + } else { + // Store the RValue into the argument struct. + Address Addr = + Builder.CreateStructGEP(ArgMemory, ArgInfo.getInAllocaFieldIndex()); + unsigned AS = Addr.getType()->getPointerAddressSpace(); + llvm::Type *MemType = ConvertTypeForMem(I->Ty)->getPointerTo(AS); + // There are some cases where a trivial bitcast is not avoidable. The + // definition of a type later in a translation unit may change it's type + // from {}* to (%struct.foo*)*. + if (Addr.getType() != MemType) + Addr = Builder.CreateBitCast(Addr, MemType); + I->copyInto(*this, Addr); + } + break; + } + + case ABIArgInfo::Indirect: { + assert(NumIRArgs == 1); + if (!I->isAggregate()) { + // Make a temporary alloca to pass the argument. + Address Addr = CreateMemTempWithoutCast( + I->Ty, ArgInfo.getIndirectAlign(), "indirect-arg-temp"); + IRCallArgs[FirstIRArg] = Addr.getPointer(); + + I->copyInto(*this, Addr); + } else { + // We want to avoid creating an unnecessary temporary+copy here; + // however, we need one in three cases: + // 1. If the argument is not byval, and we are required to copy the + // source. (This case doesn't occur on any common architecture.) + // 2. If the argument is byval, RV is not sufficiently aligned, and + // we cannot force it to be sufficiently aligned. + // 3. If the argument is byval, but RV is not located in default + // or alloca address space. + Address Addr = I->hasLValue() + ? I->getKnownLValue().getAddress() + : I->getKnownRValue().getAggregateAddress(); + llvm::Value *V = Addr.getPointer(); + CharUnits Align = ArgInfo.getIndirectAlign(); + const llvm::DataLayout *TD = &CGM.getDataLayout(); + + assert((FirstIRArg >= IRFuncTy->getNumParams() || + IRFuncTy->getParamType(FirstIRArg)->getPointerAddressSpace() == + TD->getAllocaAddrSpace()) && + "indirect argument must be in alloca address space"); + + bool NeedCopy = false; + + if (Addr.getAlignment() < Align && + llvm::getOrEnforceKnownAlignment(V, Align.getQuantity(), *TD) < + Align.getQuantity()) { + NeedCopy = true; + } else if (I->hasLValue()) { + auto LV = I->getKnownLValue(); + auto AS = LV.getAddressSpace(); + + if ((!ArgInfo.getIndirectByVal() && + (LV.getAlignment() >= + getContext().getTypeAlignInChars(I->Ty)))) { + NeedCopy = true; + } + if (!getLangOpts().OpenCL) { + if ((ArgInfo.getIndirectByVal() && + (AS != LangAS::Default && + AS != CGM.getASTAllocaAddressSpace()))) { + NeedCopy = true; + } + } + // For OpenCL even if RV is located in default or alloca address space + // we don't want to perform address space cast for it. + else if ((ArgInfo.getIndirectByVal() && + Addr.getType()->getAddressSpace() != IRFuncTy-> + getParamType(FirstIRArg)->getPointerAddressSpace())) { + NeedCopy = true; + } + } + + if (NeedCopy) { + // Create an aligned temporary, and copy to it. + Address AI = CreateMemTempWithoutCast( + I->Ty, ArgInfo.getIndirectAlign(), "byval-temp"); + IRCallArgs[FirstIRArg] = AI.getPointer(); + + // Emit lifetime markers for the temporary alloca. + uint64_t ByvalTempElementSize = + CGM.getDataLayout().getTypeAllocSize(AI.getElementType()); + llvm::Value *LifetimeSize = + EmitLifetimeStart(ByvalTempElementSize, AI.getPointer()); + + // Add cleanup code to emit the end lifetime marker after the call. + if (LifetimeSize) // In case we disabled lifetime markers. + CallLifetimeEndAfterCall.emplace_back(AI, LifetimeSize); + + // Generate the copy. + I->copyInto(*this, AI); + } else { + // Skip the extra memcpy call. + auto *T = V->getType()->getPointerElementType()->getPointerTo( + CGM.getDataLayout().getAllocaAddrSpace()); + IRCallArgs[FirstIRArg] = getTargetHooks().performAddrSpaceCast( + *this, V, LangAS::Default, CGM.getASTAllocaAddressSpace(), T, + true); + } + } + break; + } + + case ABIArgInfo::Ignore: + assert(NumIRArgs == 0); + break; + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: { + if (!isa<llvm::StructType>(ArgInfo.getCoerceToType()) && + ArgInfo.getCoerceToType() == ConvertType(info_it->type) && + ArgInfo.getDirectOffset() == 0) { + assert(NumIRArgs == 1); + llvm::Value *V; + if (!I->isAggregate()) + V = I->getKnownRValue().getScalarVal(); + else + V = Builder.CreateLoad( + I->hasLValue() ? I->getKnownLValue().getAddress() + : I->getKnownRValue().getAggregateAddress()); + + // Implement swifterror by copying into a new swifterror argument. + // We'll write back in the normal path out of the call. + if (CallInfo.getExtParameterInfo(ArgNo).getABI() + == ParameterABI::SwiftErrorResult) { + assert(!swiftErrorTemp.isValid() && "multiple swifterror args"); + + QualType pointeeTy = I->Ty->getPointeeType(); + swiftErrorArg = + Address(V, getContext().getTypeAlignInChars(pointeeTy)); + + swiftErrorTemp = + CreateMemTemp(pointeeTy, getPointerAlign(), "swifterror.temp"); + V = swiftErrorTemp.getPointer(); + cast<llvm::AllocaInst>(V)->setSwiftError(true); + + llvm::Value *errorValue = Builder.CreateLoad(swiftErrorArg); + Builder.CreateStore(errorValue, swiftErrorTemp); + } + + // We might have to widen integers, but we should never truncate. + if (ArgInfo.getCoerceToType() != V->getType() && + V->getType()->isIntegerTy()) + V = Builder.CreateZExt(V, ArgInfo.getCoerceToType()); + + // If the argument doesn't match, perform a bitcast to coerce it. This + // can happen due to trivial type mismatches. + if (FirstIRArg < IRFuncTy->getNumParams() && + V->getType() != IRFuncTy->getParamType(FirstIRArg)) + V = Builder.CreateBitCast(V, IRFuncTy->getParamType(FirstIRArg)); + + IRCallArgs[FirstIRArg] = V; + break; + } + + // FIXME: Avoid the conversion through memory if possible. + Address Src = Address::invalid(); + if (!I->isAggregate()) { + Src = CreateMemTemp(I->Ty, "coerce"); + I->copyInto(*this, Src); + } else { + Src = I->hasLValue() ? I->getKnownLValue().getAddress() + : I->getKnownRValue().getAggregateAddress(); + } + + // If the value is offset in memory, apply the offset now. + Src = emitAddressAtOffset(*this, Src, ArgInfo); + + // Fast-isel and the optimizer generally like scalar values better than + // FCAs, so we flatten them if this is safe to do for this argument. + llvm::StructType *STy = + dyn_cast<llvm::StructType>(ArgInfo.getCoerceToType()); + if (STy && ArgInfo.isDirect() && ArgInfo.getCanBeFlattened()) { + llvm::Type *SrcTy = Src.getType()->getElementType(); + uint64_t SrcSize = CGM.getDataLayout().getTypeAllocSize(SrcTy); + uint64_t DstSize = CGM.getDataLayout().getTypeAllocSize(STy); + + // If the source type is smaller than the destination type of the + // coerce-to logic, copy the source value into a temp alloca the size + // of the destination type to allow loading all of it. The bits past + // the source value are left undef. + if (SrcSize < DstSize) { + Address TempAlloca + = CreateTempAlloca(STy, Src.getAlignment(), + Src.getName() + ".coerce"); + Builder.CreateMemCpy(TempAlloca, Src, SrcSize); + Src = TempAlloca; + } else { + Src = Builder.CreateBitCast(Src, + STy->getPointerTo(Src.getAddressSpace())); + } + + assert(NumIRArgs == STy->getNumElements()); + for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { + Address EltPtr = Builder.CreateStructGEP(Src, i); + llvm::Value *LI = Builder.CreateLoad(EltPtr); + IRCallArgs[FirstIRArg + i] = LI; + } + } else { + // In the simple case, just pass the coerced loaded value. + assert(NumIRArgs == 1); + IRCallArgs[FirstIRArg] = + CreateCoercedLoad(Src, ArgInfo.getCoerceToType(), *this); + } + + break; + } + + case ABIArgInfo::CoerceAndExpand: { + auto coercionType = ArgInfo.getCoerceAndExpandType(); + auto layout = CGM.getDataLayout().getStructLayout(coercionType); + + llvm::Value *tempSize = nullptr; + Address addr = Address::invalid(); + Address AllocaAddr = Address::invalid(); + if (I->isAggregate()) { + addr = I->hasLValue() ? I->getKnownLValue().getAddress() + : I->getKnownRValue().getAggregateAddress(); + + } else { + RValue RV = I->getKnownRValue(); + assert(RV.isScalar()); // complex should always just be direct + + llvm::Type *scalarType = RV.getScalarVal()->getType(); + auto scalarSize = CGM.getDataLayout().getTypeAllocSize(scalarType); + auto scalarAlign = CGM.getDataLayout().getPrefTypeAlignment(scalarType); + + // Materialize to a temporary. + addr = CreateTempAlloca( + RV.getScalarVal()->getType(), + CharUnits::fromQuantity(std::max( + (unsigned)layout->getAlignment().value(), scalarAlign)), + "tmp", + /*ArraySize=*/nullptr, &AllocaAddr); + tempSize = EmitLifetimeStart(scalarSize, AllocaAddr.getPointer()); + + Builder.CreateStore(RV.getScalarVal(), addr); + } + + addr = Builder.CreateElementBitCast(addr, coercionType); + + unsigned IRArgPos = FirstIRArg; + for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) { + llvm::Type *eltType = coercionType->getElementType(i); + if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType)) continue; + Address eltAddr = Builder.CreateStructGEP(addr, i); + llvm::Value *elt = Builder.CreateLoad(eltAddr); + IRCallArgs[IRArgPos++] = elt; + } + assert(IRArgPos == FirstIRArg + NumIRArgs); + + if (tempSize) { + EmitLifetimeEnd(tempSize, AllocaAddr.getPointer()); + } + + break; + } + + case ABIArgInfo::Expand: + unsigned IRArgPos = FirstIRArg; + ExpandTypeToArgs(I->Ty, *I, IRFuncTy, IRCallArgs, IRArgPos); + assert(IRArgPos == FirstIRArg + NumIRArgs); + break; + } + } + + const CGCallee &ConcreteCallee = Callee.prepareConcreteCallee(*this); + llvm::Value *CalleePtr = ConcreteCallee.getFunctionPointer(); + + // If we're using inalloca, set up that argument. + if (ArgMemory.isValid()) { + llvm::Value *Arg = ArgMemory.getPointer(); + if (CallInfo.isVariadic()) { + // When passing non-POD arguments by value to variadic functions, we will + // end up with a variadic prototype and an inalloca call site. In such + // cases, we can't do any parameter mismatch checks. Give up and bitcast + // the callee. + unsigned CalleeAS = CalleePtr->getType()->getPointerAddressSpace(); + CalleePtr = + Builder.CreateBitCast(CalleePtr, IRFuncTy->getPointerTo(CalleeAS)); + } else { + llvm::Type *LastParamTy = + IRFuncTy->getParamType(IRFuncTy->getNumParams() - 1); + if (Arg->getType() != LastParamTy) { +#ifndef NDEBUG + // Assert that these structs have equivalent element types. + llvm::StructType *FullTy = CallInfo.getArgStruct(); + llvm::StructType *DeclaredTy = cast<llvm::StructType>( + cast<llvm::PointerType>(LastParamTy)->getElementType()); + assert(DeclaredTy->getNumElements() == FullTy->getNumElements()); + for (llvm::StructType::element_iterator DI = DeclaredTy->element_begin(), + DE = DeclaredTy->element_end(), + FI = FullTy->element_begin(); + DI != DE; ++DI, ++FI) + assert(*DI == *FI); +#endif + Arg = Builder.CreateBitCast(Arg, LastParamTy); + } + } + assert(IRFunctionArgs.hasInallocaArg()); + IRCallArgs[IRFunctionArgs.getInallocaArgNo()] = Arg; + } + + // 2. Prepare the function pointer. + + // If the callee is a bitcast of a non-variadic function to have a + // variadic function pointer type, check to see if we can remove the + // bitcast. This comes up with unprototyped functions. + // + // This makes the IR nicer, but more importantly it ensures that we + // can inline the function at -O0 if it is marked always_inline. + auto simplifyVariadicCallee = [](llvm::FunctionType *CalleeFT, + llvm::Value *Ptr) -> llvm::Function * { + if (!CalleeFT->isVarArg()) + return nullptr; + + // Get underlying value if it's a bitcast + if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Ptr)) { + if (CE->getOpcode() == llvm::Instruction::BitCast) + Ptr = CE->getOperand(0); + } + + llvm::Function *OrigFn = dyn_cast<llvm::Function>(Ptr); + if (!OrigFn) + return nullptr; + + llvm::FunctionType *OrigFT = OrigFn->getFunctionType(); + + // If the original type is variadic, or if any of the component types + // disagree, we cannot remove the cast. + if (OrigFT->isVarArg() || + OrigFT->getNumParams() != CalleeFT->getNumParams() || + OrigFT->getReturnType() != CalleeFT->getReturnType()) + return nullptr; + + for (unsigned i = 0, e = OrigFT->getNumParams(); i != e; ++i) + if (OrigFT->getParamType(i) != CalleeFT->getParamType(i)) + return nullptr; + + return OrigFn; + }; + + if (llvm::Function *OrigFn = simplifyVariadicCallee(IRFuncTy, CalleePtr)) { + CalleePtr = OrigFn; + IRFuncTy = OrigFn->getFunctionType(); + } + + // 3. Perform the actual call. + + // Deactivate any cleanups that we're supposed to do immediately before + // the call. + if (!CallArgs.getCleanupsToDeactivate().empty()) + deactivateArgCleanupsBeforeCall(*this, CallArgs); + + // Assert that the arguments we computed match up. The IR verifier + // will catch this, but this is a common enough source of problems + // during IRGen changes that it's way better for debugging to catch + // it ourselves here. +#ifndef NDEBUG + assert(IRCallArgs.size() == IRFuncTy->getNumParams() || IRFuncTy->isVarArg()); + for (unsigned i = 0; i < IRCallArgs.size(); ++i) { + // Inalloca argument can have different type. + if (IRFunctionArgs.hasInallocaArg() && + i == IRFunctionArgs.getInallocaArgNo()) + continue; + if (i < IRFuncTy->getNumParams()) + assert(IRCallArgs[i]->getType() == IRFuncTy->getParamType(i)); + } +#endif + + // Update the largest vector width if any arguments have vector types. + for (unsigned i = 0; i < IRCallArgs.size(); ++i) { + if (auto *VT = dyn_cast<llvm::VectorType>(IRCallArgs[i]->getType())) + LargestVectorWidth = std::max((uint64_t)LargestVectorWidth, + VT->getPrimitiveSizeInBits().getFixedSize()); + } + + // Compute the calling convention and attributes. + unsigned CallingConv; + llvm::AttributeList Attrs; + CGM.ConstructAttributeList(CalleePtr->getName(), CallInfo, + Callee.getAbstractInfo(), Attrs, CallingConv, + /*AttrOnCallSite=*/true); + + // Apply some call-site-specific attributes. + // TODO: work this into building the attribute set. + + // Apply always_inline to all calls within flatten functions. + // FIXME: should this really take priority over __try, below? + if (CurCodeDecl && CurCodeDecl->hasAttr<FlattenAttr>() && + !(TargetDecl && TargetDecl->hasAttr<NoInlineAttr>())) { + Attrs = + Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex, + llvm::Attribute::AlwaysInline); + } + + // Disable inlining inside SEH __try blocks. + if (isSEHTryScope()) { + Attrs = + Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex, + llvm::Attribute::NoInline); + } + + // Decide whether to use a call or an invoke. + bool CannotThrow; + if (currentFunctionUsesSEHTry()) { + // SEH cares about asynchronous exceptions, so everything can "throw." + CannotThrow = false; + } else if (isCleanupPadScope() && + EHPersonality::get(*this).isMSVCXXPersonality()) { + // The MSVC++ personality will implicitly terminate the program if an + // exception is thrown during a cleanup outside of a try/catch. + // We don't need to model anything in IR to get this behavior. + CannotThrow = true; + } else { + // Otherwise, nounwind call sites will never throw. + CannotThrow = Attrs.hasAttribute(llvm::AttributeList::FunctionIndex, + llvm::Attribute::NoUnwind); + } + + // If we made a temporary, be sure to clean up after ourselves. Note that we + // can't depend on being inside of an ExprWithCleanups, so we need to manually + // pop this cleanup later on. Being eager about this is OK, since this + // temporary is 'invisible' outside of the callee. + if (UnusedReturnSizePtr) + pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, SRetAlloca, + UnusedReturnSizePtr); + + llvm::BasicBlock *InvokeDest = CannotThrow ? nullptr : getInvokeDest(); + + SmallVector<llvm::OperandBundleDef, 1> BundleList = + getBundlesForFunclet(CalleePtr); + + // Emit the actual call/invoke instruction. + llvm::CallBase *CI; + if (!InvokeDest) { + CI = Builder.CreateCall(IRFuncTy, CalleePtr, IRCallArgs, BundleList); + } else { + llvm::BasicBlock *Cont = createBasicBlock("invoke.cont"); + CI = Builder.CreateInvoke(IRFuncTy, CalleePtr, Cont, InvokeDest, IRCallArgs, + BundleList); + EmitBlock(Cont); + } + if (callOrInvoke) + *callOrInvoke = CI; + + // Apply the attributes and calling convention. + CI->setAttributes(Attrs); + CI->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); + + // Apply various metadata. + + if (!CI->getType()->isVoidTy()) + CI->setName("call"); + + // Update largest vector width from the return type. + if (auto *VT = dyn_cast<llvm::VectorType>(CI->getType())) + LargestVectorWidth = std::max((uint64_t)LargestVectorWidth, + VT->getPrimitiveSizeInBits().getFixedSize()); + + // Insert instrumentation or attach profile metadata at indirect call sites. + // For more details, see the comment before the definition of + // IPVK_IndirectCallTarget in InstrProfData.inc. + if (!CI->getCalledFunction()) + PGO.valueProfile(Builder, llvm::IPVK_IndirectCallTarget, + CI, CalleePtr); + + // In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC + // optimizer it can aggressively ignore unwind edges. + if (CGM.getLangOpts().ObjCAutoRefCount) + AddObjCARCExceptionMetadata(CI); + + // Suppress tail calls if requested. + if (llvm::CallInst *Call = dyn_cast<llvm::CallInst>(CI)) { + if (TargetDecl && TargetDecl->hasAttr<NotTailCalledAttr>()) + Call->setTailCallKind(llvm::CallInst::TCK_NoTail); + } + + // Add metadata for calls to MSAllocator functions + if (getDebugInfo() && TargetDecl && + TargetDecl->hasAttr<MSAllocatorAttr>()) + getDebugInfo()->addHeapAllocSiteMetadata(CI, RetTy, Loc); + + // 4. Finish the call. + + // If the call doesn't return, finish the basic block and clear the + // insertion point; this allows the rest of IRGen to discard + // unreachable code. + if (CI->doesNotReturn()) { + if (UnusedReturnSizePtr) + PopCleanupBlock(); + + // Strip away the noreturn attribute to better diagnose unreachable UB. + if (SanOpts.has(SanitizerKind::Unreachable)) { + // Also remove from function since CallBase::hasFnAttr additionally checks + // attributes of the called function. + if (auto *F = CI->getCalledFunction()) + F->removeFnAttr(llvm::Attribute::NoReturn); + CI->removeAttribute(llvm::AttributeList::FunctionIndex, + llvm::Attribute::NoReturn); + + // Avoid incompatibility with ASan which relies on the `noreturn` + // attribute to insert handler calls. + if (SanOpts.hasOneOf(SanitizerKind::Address | + SanitizerKind::KernelAddress)) { + SanitizerScope SanScope(this); + llvm::IRBuilder<>::InsertPointGuard IPGuard(Builder); + Builder.SetInsertPoint(CI); + auto *FnType = llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false); + llvm::FunctionCallee Fn = + CGM.CreateRuntimeFunction(FnType, "__asan_handle_no_return"); + EmitNounwindRuntimeCall(Fn); + } + } + + EmitUnreachable(Loc); + Builder.ClearInsertionPoint(); + + // FIXME: For now, emit a dummy basic block because expr emitters in + // generally are not ready to handle emitting expressions at unreachable + // points. + EnsureInsertPoint(); + + // Return a reasonable RValue. + return GetUndefRValue(RetTy); + } + + // Perform the swifterror writeback. + if (swiftErrorTemp.isValid()) { + llvm::Value *errorResult = Builder.CreateLoad(swiftErrorTemp); + Builder.CreateStore(errorResult, swiftErrorArg); + } + + // Emit any call-associated writebacks immediately. Arguably this + // should happen after any return-value munging. + if (CallArgs.hasWritebacks()) + emitWritebacks(*this, CallArgs); + + // The stack cleanup for inalloca arguments has to run out of the normal + // lexical order, so deactivate it and run it manually here. + CallArgs.freeArgumentMemory(*this); + + // Extract the return value. + RValue Ret = [&] { + switch (RetAI.getKind()) { + case ABIArgInfo::CoerceAndExpand: { + auto coercionType = RetAI.getCoerceAndExpandType(); + + Address addr = SRetPtr; + addr = Builder.CreateElementBitCast(addr, coercionType); + + assert(CI->getType() == RetAI.getUnpaddedCoerceAndExpandType()); + bool requiresExtract = isa<llvm::StructType>(CI->getType()); + + unsigned unpaddedIndex = 0; + for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) { + llvm::Type *eltType = coercionType->getElementType(i); + if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType)) continue; + Address eltAddr = Builder.CreateStructGEP(addr, i); + llvm::Value *elt = CI; + if (requiresExtract) + elt = Builder.CreateExtractValue(elt, unpaddedIndex++); + else + assert(unpaddedIndex == 0); + Builder.CreateStore(elt, eltAddr); + } + // FALLTHROUGH + LLVM_FALLTHROUGH; + } + + case ABIArgInfo::InAlloca: + case ABIArgInfo::Indirect: { + RValue ret = convertTempToRValue(SRetPtr, RetTy, SourceLocation()); + if (UnusedReturnSizePtr) + PopCleanupBlock(); + return ret; + } + + case ABIArgInfo::Ignore: + // If we are ignoring an argument that had a result, make sure to + // construct the appropriate return value for our caller. + return GetUndefRValue(RetTy); + + case ABIArgInfo::Extend: + case ABIArgInfo::Direct: { + llvm::Type *RetIRTy = ConvertType(RetTy); + if (RetAI.getCoerceToType() == RetIRTy && RetAI.getDirectOffset() == 0) { + switch (getEvaluationKind(RetTy)) { + case TEK_Complex: { + llvm::Value *Real = Builder.CreateExtractValue(CI, 0); + llvm::Value *Imag = Builder.CreateExtractValue(CI, 1); + return RValue::getComplex(std::make_pair(Real, Imag)); + } + case TEK_Aggregate: { + Address DestPtr = ReturnValue.getValue(); + bool DestIsVolatile = ReturnValue.isVolatile(); + + if (!DestPtr.isValid()) { + DestPtr = CreateMemTemp(RetTy, "agg.tmp"); + DestIsVolatile = false; + } + BuildAggStore(*this, CI, DestPtr, DestIsVolatile); + return RValue::getAggregate(DestPtr); + } + case TEK_Scalar: { + // If the argument doesn't match, perform a bitcast to coerce it. This + // can happen due to trivial type mismatches. + llvm::Value *V = CI; + if (V->getType() != RetIRTy) + V = Builder.CreateBitCast(V, RetIRTy); + return RValue::get(V); + } + } + llvm_unreachable("bad evaluation kind"); + } + + Address DestPtr = ReturnValue.getValue(); + bool DestIsVolatile = ReturnValue.isVolatile(); + + if (!DestPtr.isValid()) { + DestPtr = CreateMemTemp(RetTy, "coerce"); + DestIsVolatile = false; + } + + // If the value is offset in memory, apply the offset now. + Address StorePtr = emitAddressAtOffset(*this, DestPtr, RetAI); + CreateCoercedStore(CI, StorePtr, DestIsVolatile, *this); + + return convertTempToRValue(DestPtr, RetTy, SourceLocation()); + } + + case ABIArgInfo::Expand: + llvm_unreachable("Invalid ABI kind for return argument"); + } + + llvm_unreachable("Unhandled ABIArgInfo::Kind"); + } (); + + // Emit the assume_aligned check on the return value. + if (Ret.isScalar() && TargetDecl) { + if (const auto *AA = TargetDecl->getAttr<AssumeAlignedAttr>()) { + llvm::Value *OffsetValue = nullptr; + if (const auto *Offset = AA->getOffset()) + OffsetValue = EmitScalarExpr(Offset); + + llvm::Value *Alignment = EmitScalarExpr(AA->getAlignment()); + llvm::ConstantInt *AlignmentCI = cast<llvm::ConstantInt>(Alignment); + EmitAlignmentAssumption(Ret.getScalarVal(), RetTy, Loc, AA->getLocation(), + AlignmentCI, OffsetValue); + } else if (const auto *AA = TargetDecl->getAttr<AllocAlignAttr>()) { + llvm::Value *AlignmentVal = CallArgs[AA->getParamIndex().getLLVMIndex()] + .getRValue(*this) + .getScalarVal(); + EmitAlignmentAssumption(Ret.getScalarVal(), RetTy, Loc, AA->getLocation(), + AlignmentVal); + } + } + + // Explicitly call CallLifetimeEnd::Emit just to re-use the code even though + // we can't use the full cleanup mechanism. + for (CallLifetimeEnd &LifetimeEnd : CallLifetimeEndAfterCall) + LifetimeEnd.Emit(*this, /*Flags=*/{}); + + return Ret; +} + +CGCallee CGCallee::prepareConcreteCallee(CodeGenFunction &CGF) const { + if (isVirtual()) { + const CallExpr *CE = getVirtualCallExpr(); + return CGF.CGM.getCXXABI().getVirtualFunctionPointer( + CGF, getVirtualMethodDecl(), getThisAddress(), getVirtualFunctionType(), + CE ? CE->getBeginLoc() : SourceLocation()); + } + + return *this; +} + +/* VarArg handling */ + +Address CodeGenFunction::EmitVAArg(VAArgExpr *VE, Address &VAListAddr) { + VAListAddr = VE->isMicrosoftABI() + ? EmitMSVAListRef(VE->getSubExpr()) + : EmitVAListRef(VE->getSubExpr()); + QualType Ty = VE->getType(); + if (VE->isMicrosoftABI()) + return CGM.getTypes().getABIInfo().EmitMSVAArg(*this, VAListAddr, Ty); + return CGM.getTypes().getABIInfo().EmitVAArg(*this, VAListAddr, Ty); +} |