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llvm/llvm-project/clang/refs/heads/main/./lib/CodeGen/CGCall.cpp
blob: 5a05f8686b70b5697abaeccbec3978766a3d1e60 [file] [edit]
//===--- 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 "ABIInfoImpl.h"
#include "CGBlocks.h"
#include "CGCXXABI.h"
#include "CGCleanup.h"
#include "CGDebugInfo.h"
#include "CGRecordLayout.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "CodeGenPGO.h"
#include "QualTypeMapper.h"
#include "TargetInfo.h"
#include "clang/AST/Attr.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/RecordLayout.h"
#include "clang/Basic/CodeGenOptions.h"
#include "clang/Basic/DiagnosticFrontend.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/CodeGen/CGFunctionInfo.h"
#include "clang/CodeGen/SwiftCallingConv.h"
#include "clang/CodeGenUtils/CallUtils.h"
#include "llvm/ABI/FunctionInfo.h"
#include "llvm/ABI/IRTypeMapper.h"
#include "llvm/ABI/TargetInfo.h"
#include "llvm/ABI/Types.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Assumptions.h"
#include "llvm/IR/AttributeMask.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Type.h"
#include "llvm/Transforms/Utils/Local.h"
#include <optional>
using namespace clang;
using namespace CodeGen;
/***/
unsigned CodeGenTypes::ClangCallConvToLLVMCallConv(CallingConv CC) {
switch (CC) {
case CC_C:
// On SPIR/SPIR-V, CC_C is the AST-level default calling convention, but
// it still needs to lower to spir_func so IR consumers can rely on the
// calling convention to distinguish device functions.
if (Target.getTriple().isSPIROrSPIRV())
return llvm::CallingConv::SPIR_FUNC;
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_AArch64SVEPCS:
return llvm::CallingConv::AArch64_SVE_VectorCall;
case CC_DeviceKernel:
return CGM.getTargetCodeGenInfo().getDeviceKernelCallingConv();
case CC_PreserveMost:
return llvm::CallingConv::PreserveMost;
case CC_PreserveAll:
return llvm::CallingConv::PreserveAll;
case CC_Swift:
return llvm::CallingConv::Swift;
case CC_SwiftAsync:
return llvm::CallingConv::SwiftTail;
case CC_M68kRTD:
return llvm::CallingConv::M68k_RTD;
case CC_PreserveNone:
return llvm::CallingConv::PreserveNone;
// clang-format off
case CC_RISCVVectorCall: return llvm::CallingConv::RISCV_VectorCall;
// clang-format on
#define CC_VLS_CASE(ABI_VLEN) \
case CC_RISCVVLSCall_##ABI_VLEN: \
return llvm::CallingConv::RISCV_VLSCall_##ABI_VLEN;
CC_VLS_CASE(32)
CC_VLS_CASE(64)
CC_VLS_CASE(128)
CC_VLS_CASE(256)
CC_VLS_CASE(512)
CC_VLS_CASE(1024)
CC_VLS_CASE(2048)
CC_VLS_CASE(4096)
CC_VLS_CASE(8192)
CC_VLS_CASE(16384)
CC_VLS_CASE(32768)
CC_VLS_CASE(65536)
#undef CC_VLS_CASE
}
llvm_unreachable("unhandled calling convention");
}
/// 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) {
CanQualType RecTy;
if (RD)
RecTy = Context.getCanonicalTagType(RD);
else
RecTy = Context.VoidTy;
if (MD)
RecTy = CanQualType::CreateUnsafe(Context.getAddrSpaceQualType(
RecTy, MD->getMethodQualifiers().getAddressSpace()));
return Context.getPointerType(RecTy);
}
/// 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();
}
/// 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(),
FnInfoOpts::None, {}, FTNP->getExtInfo(), {},
RequiredArgs(0), /*ABIInfoFD=*/nullptr);
}
static void addExtParameterInfosForCall(
llvm::SmallVectorImpl<FunctionProtoType::ExtParameterInfo> &paramInfos,
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> &paramInfos,
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().getCanonicalSizeType());
}
addExtParameterInfosForCall(paramInfos, FPT.getTypePtr(), PrefixSize,
prefix.size());
}
using ExtParameterInfoList =
SmallVector<FunctionProtoType::ExtParameterInfo, 16>;
/// 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) {
ExtParameterInfoList paramInfos;
RequiredArgs Required = RequiredArgs::forPrototypePlus(FTP, prefix.size());
appendParameterTypes(CGT, prefix, paramInfos, FTP);
CanQualType resultType = FTP->getReturnType().getUnqualifiedType();
FnInfoOpts opts =
instanceMethod ? FnInfoOpts::IsInstanceMethod : FnInfoOpts::None;
return CGT.arrangeLLVMFunctionInfo(resultType, opts, prefix,
FTP->getExtInfo(), paramInfos, Required,
/*ABIInfoFD=*/nullptr);
}
using CanQualTypeList = SmallVector<CanQualType, 16>;
/// Arrange the argument and result information for a value of the
/// given freestanding function type.
const CGFunctionInfo &
CodeGenTypes::arrangeFreeFunctionType(CanQual<FunctionProtoType> FTP) {
CanQualTypeList argTypes;
return ::arrangeLLVMFunctionInfo(*this, /*instanceMethod=*/false, argTypes,
FTP);
}
static CallingConv getCallingConventionForDecl(const ObjCMethodDecl *D,
bool IsTargetDefaultMSABI) {
// 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<AArch64SVEPcsAttr>())
return CC_AArch64SVEPCS;
if (D->hasAttr<DeviceKernelAttr>())
return CC_DeviceKernel;
if (D->hasAttr<IntelOclBiccAttr>())
return CC_IntelOclBicc;
if (D->hasAttr<MSABIAttr>())
return IsTargetDefaultMSABI ? CC_C : CC_Win64;
if (D->hasAttr<SysVABIAttr>())
return IsTargetDefaultMSABI ? CC_X86_64SysV : CC_C;
if (D->hasAttr<PreserveMostAttr>())
return CC_PreserveMost;
if (D->hasAttr<PreserveAllAttr>())
return CC_PreserveAll;
if (D->hasAttr<M68kRTDAttr>())
return CC_M68kRTD;
if (D->hasAttr<PreserveNoneAttr>())
return CC_PreserveNone;
if (D->hasAttr<RISCVVectorCCAttr>())
return CC_RISCVVectorCall;
if (RISCVVLSCCAttr *PCS = D->getAttr<RISCVVLSCCAttr>()) {
switch (PCS->getVectorWidth()) {
default:
llvm_unreachable("Invalid RISC-V VLS ABI VLEN");
#define CC_VLS_CASE(ABI_VLEN) \
case ABI_VLEN: \
return CC_RISCVVLSCall_##ABI_VLEN;
CC_VLS_CASE(32)
CC_VLS_CASE(64)
CC_VLS_CASE(128)
CC_VLS_CASE(256)
CC_VLS_CASE(512)
CC_VLS_CASE(1024)
CC_VLS_CASE(2048)
CC_VLS_CASE(4096)
CC_VLS_CASE(8192)
CC_VLS_CASE(16384)
CC_VLS_CASE(32768)
CC_VLS_CASE(65536)
#undef CC_VLS_CASE
}
}
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) {
CanQualTypeList argTypes;
// Add the 'this' pointer.
argTypes.push_back(DeriveThisType(RD, MD));
auto CanonicalFTP =
FTP->getCanonicalTypeUnqualified().getAs<FunctionProtoType>();
ExtParameterInfoList paramInfos;
RequiredArgs required = RequiredArgs::forPrototypePlus(
CanonicalFTP.getTypePtr(), argTypes.size());
appendParameterTypes(*this, argTypes, paramInfos, CanonicalFTP);
return arrangeLLVMFunctionInfo(
CanonicalFTP->getReturnType().getUnqualifiedType(),
FnInfoOpts::IsInstanceMethod, argTypes, CanonicalFTP->getExtInfo(),
paramInfos, required, MD);
}
/// 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 = CodeGenUtils::getFormalType(MD).getAs<Type>();
setCUDAKernelCallingConvention(FT, CGM, MD);
auto prototype = FT.getAs<FunctionProtoType>();
if (MD->isImplicitObjectMemberFunction()) {
// The abstract case is perfectly fine.
const CXXRecordDecl *ThisType =
getCXXABI().getThisArgumentTypeForMethod(MD);
return arrangeCXXMethodType(ThisType, prototype.getTypePtr(), MD);
}
CanQualTypeList argTypes;
ExtParameterInfoList paramInfos;
appendParameterTypes(*this, argTypes, paramInfos, prototype);
return arrangeLLVMFunctionInfo(
prototype->getReturnType().getUnqualifiedType(), FnInfoOpts::None,
argTypes, prototype->getExtInfo(), paramInfos,
RequiredArgs::forPrototypePlus(prototype.getTypePtr(), 0), MD);
}
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());
CanQualTypeList argTypes;
ExtParameterInfoList paramInfos;
const CXXRecordDecl *ThisType = getCXXABI().getThisArgumentTypeForMethod(GD);
argTypes.push_back(DeriveThisType(ThisType, 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 = CodeGenUtils::getFormalType(MD);
// Add the formal parameters.
if (PassParams)
appendParameterTypes(*this, argTypes, paramInfos, FTP);
CGCXXABI::AddedStructorArgCounts AddedArgs =
getCXXABI().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 = getCXXABI().HasThisReturn(GD) ? argTypes.front()
: getCXXABI().hasMostDerivedReturn(GD)
? CGM.getContext().VoidPtrTy
: Context.VoidTy;
return arrangeLLVMFunctionInfo(resultType, FnInfoOpts::IsInstanceMethod,
argTypes, extInfo, paramInfos, required, MD);
}
static CanQualTypeList getArgTypesForCall(ASTContext &ctx,
const CallArgList &args) {
CanQualTypeList argTypes;
for (auto &arg : args)
argTypes.push_back(ctx.getCanonicalParamType(arg.Ty));
return argTypes;
}
static CanQualTypeList getArgTypesForDeclaration(ASTContext &ctx,
const FunctionArgList &args) {
CanQualTypeList argTypes;
for (auto &arg : args)
argTypes.push_back(ctx.getCanonicalParamType(arg->getType()));
return argTypes;
}
static ExtParameterInfoList
getExtParameterInfosForCall(const FunctionProtoType *proto, unsigned prefixArgs,
unsigned totalArgs) {
ExtParameterInfoList 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,
const FunctionDecl *ABIInfoFD, bool PassProtoArgs) {
CanQualTypeList 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 = CodeGenUtils::getFormalType(D);
RequiredArgs Required = PassProtoArgs
? RequiredArgs::forPrototypePlus(
FPT, TotalPrefixArgs + ExtraSuffixArgs)
: RequiredArgs::All;
GlobalDecl GD(D, CtorKind);
CanQualType ResultType = getCXXABI().HasThisReturn(GD) ? ArgTypes.front()
: getCXXABI().hasMostDerivedReturn(GD)
? CGM.getContext().VoidPtrTy
: Context.VoidTy;
FunctionType::ExtInfo Info = FPT->getExtInfo();
ExtParameterInfoList 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, FnInfoOpts::IsInstanceMethod,
ArgTypes, Info, ParamInfos, Required,
ABIInfoFD);
}
/// Arrange the argument and result information for the declaration or
/// definition of the given function.
const CGFunctionInfo &
CodeGenTypes::arrangeFunctionDeclaration(const GlobalDecl GD) {
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
if (MD->isImplicitObjectMemberFunction())
return arrangeCXXMethodDeclaration(MD);
CanQualType FTy = FD->getType()->getCanonicalTypeUnqualified();
assert(isa<FunctionType>(FTy));
setCUDAKernelCallingConvention(FTy, CGM, FD);
if (DeviceKernelAttr::isOpenCLSpelling(FD->getAttr<DeviceKernelAttr>()) &&
GD.getKernelReferenceKind() == KernelReferenceKind::Stub) {
const FunctionType *FT = FTy->getAs<FunctionType>();
CGM.getTargetCodeGenInfo().setOCLKernelStubCallingConvention(FT);
FTy = FT->getCanonicalTypeUnqualified();
}
// When declaring a function without a prototype, always use a
// non-variadic type.
if (CanQual<FunctionNoProtoType> noProto = FTy.getAs<FunctionNoProtoType>()) {
return arrangeLLVMFunctionInfo(noProto->getReturnType(), FnInfoOpts::None,
{}, noProto->getExtInfo(), {},
RequiredArgs::All, FD);
}
CanQual<FunctionProtoType> FTP = FTy.castAs<FunctionProtoType>();
CanQualTypeList argTypes;
ExtParameterInfoList paramInfos;
appendParameterTypes(*this, argTypes, paramInfos, FTP);
return arrangeLLVMFunctionInfo(FTP->getReturnType().getUnqualifiedType(),
FnInfoOpts::None, argTypes, FTP->getExtInfo(),
paramInfos,
RequiredArgs::forPrototypePlus(FTP, 0), FD);
}
/// 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) {
CanQualTypeList argTys;
ExtParameterInfoList extParamInfos(MD->isDirectMethod() ? 1 : 2);
argTys.push_back(Context.getCanonicalParamType(receiverType));
if (!MD->isDirectMethod())
argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType()));
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 IsTargetDefaultMSABI =
getContext().getTargetInfo().getTriple().isOSWindows() ||
getContext().getTargetInfo().getTriple().isUEFI();
einfo = einfo.withCallingConv(
getCallingConventionForDecl(MD, IsTargetDefaultMSABI));
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()),
FnInfoOpts::None, argTys, einfo, extParamInfos,
required, /*ABIInfoFD=*/nullptr);
}
const CGFunctionInfo &
CodeGenTypes::arrangeUnprototypedObjCMessageSend(QualType returnType,
const CallArgList &args) {
CanQualTypeList argTypes = getArgTypesForCall(Context, args);
FunctionType::ExtInfo einfo;
return arrangeLLVMFunctionInfo(GetReturnType(returnType), FnInfoOpts::None,
argTypes, einfo, {}, RequiredArgs::All,
nullptr);
}
const CGFunctionInfo &CodeGenTypes::arrangeGlobalDeclaration(GlobalDecl GD) {
// FIXME: Do we need to handle ObjCMethodDecl?
if (isa<CXXConstructorDecl>(GD.getDecl()) ||
isa<CXXDestructorDecl>(GD.getDecl()))
return arrangeCXXStructorDeclaration(GD);
return arrangeFunctionDeclaration(GD);
}
/// 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 = CodeGenUtils::getFormalType(MD);
CanQualType ArgTys[] = {DeriveThisType(MD->getParent(), MD)};
return arrangeLLVMFunctionInfo(Context.VoidTy, FnInfoOpts::None, ArgTys,
FTP->getExtInfo(), {}, RequiredArgs(1), MD);
}
const CGFunctionInfo &
CodeGenTypes::arrangeMSCtorClosure(const CXXConstructorDecl *CD,
CXXCtorType CT) {
assert(CT == Ctor_CopyingClosure || CT == Ctor_DefaultClosure);
CanQual<FunctionProtoType> FTP = CodeGenUtils::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, FnInfoOpts::IsInstanceMethod,
ArgTys, FunctionType::ExtInfo(CC), {},
RequiredArgs::All, /*ABIInfoFD=*/nullptr);
}
/// 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,
const FunctionDecl *ABIInfoFD) {
assert(args.size() >= numExtraRequiredArgs);
ExtParameterInfoList 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());
}
CanQualTypeList argTypes;
for (const auto &arg : args)
argTypes.push_back(CGT.getContext().getCanonicalParamType(arg.Ty));
FnInfoOpts opts = chainCall ? FnInfoOpts::IsChainCall : FnInfoOpts::None;
return CGT.arrangeLLVMFunctionInfo(GetReturnType(fnType->getReturnType()),
opts, argTypes, fnType->getExtInfo(),
paramInfos, required, ABIInfoFD);
}
/// 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,
const FunctionDecl *ABIInfoFD) {
return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType,
chainCall ? 1 : 0, chainCall, ABIInfoFD);
}
/// A block function is essentially a free function with an
/// extra implicit argument.
const CGFunctionInfo &
CodeGenTypes::arrangeBlockFunctionCall(const CallArgList &args,
const FunctionType *fnType) {
// FIXME: Pass the enclosing function's ABI information so block calls use
// the caller's target features.
return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType, 1,
/*chainCall=*/false, nullptr);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBlockFunctionDeclaration(const FunctionProtoType *proto,
const FunctionArgList &params) {
ExtParameterInfoList paramInfos =
getExtParameterInfosForCall(proto, 1, params.size());
CanQualTypeList argTypes = getArgTypesForDeclaration(Context, params);
// FIXME: Use the block's target features when arranging its invoke function.
return arrangeLLVMFunctionInfo(
GetReturnType(proto->getReturnType()), FnInfoOpts::None, argTypes,
proto->getExtInfo(), paramInfos, RequiredArgs::forPrototypePlus(proto, 1),
/*ABIInfoFD=*/nullptr);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBuiltinFunctionCall(QualType resultType,
const CallArgList &args) {
CanQualTypeList argTypes;
for (const auto &Arg : args)
argTypes.push_back(Context.getCanonicalParamType(Arg.Ty));
return arrangeLLVMFunctionInfo(GetReturnType(resultType), FnInfoOpts::None,
argTypes, FunctionType::ExtInfo(),
/*paramInfos=*/{}, RequiredArgs::All, nullptr);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBuiltinFunctionDeclaration(QualType resultType,
const FunctionArgList &args) {
CanQualTypeList argTypes = getArgTypesForDeclaration(Context, args);
return arrangeLLVMFunctionInfo(GetReturnType(resultType), FnInfoOpts::None,
argTypes, FunctionType::ExtInfo(), {},
RequiredArgs::All, /*ABIInfoFD=*/nullptr);
}
const CGFunctionInfo &CodeGenTypes::arrangeBuiltinFunctionDeclaration(
CanQualType resultType, ArrayRef<CanQualType> argTypes) {
return arrangeLLVMFunctionInfo(resultType, FnInfoOpts::None, argTypes,
FunctionType::ExtInfo(), {}, RequiredArgs::All,
/*ABIInfoFD=*/nullptr);
}
const CGFunctionInfo &CodeGenTypes::arrangeDeviceKernelCallerDeclaration(
QualType resultType, const FunctionArgList &args) {
CanQualTypeList argTypes = getArgTypesForDeclaration(Context, args);
return arrangeLLVMFunctionInfo(GetReturnType(resultType), FnInfoOpts::None,
argTypes,
FunctionType::ExtInfo(CC_DeviceKernel),
/*paramInfos=*/{}, RequiredArgs::All,
/*ABIInfoFD=*/nullptr);
}
/// 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,
const FunctionDecl *ABIInfoFD) {
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.
ExtParameterInfoList paramInfos =
getExtParameterInfosForCall(proto, numPrefixArgs + 1, args.size());
CanQualTypeList argTypes = getArgTypesForCall(Context, args);
FunctionType::ExtInfo info = proto->getExtInfo();
return arrangeLLVMFunctionInfo(GetReturnType(proto->getReturnType()),
FnInfoOpts::IsInstanceMethod, argTypes, info,
paramInfos, required, ABIInfoFD);
}
const CGFunctionInfo &CodeGenTypes::arrangeNullaryFunction() {
return arrangeLLVMFunctionInfo(getContext().VoidTy, FnInfoOpts::None, {},
FunctionType::ExtInfo(), {}, RequiredArgs::All,
/*ABIInfoFD=*/nullptr);
}
const CGFunctionInfo &CodeGenTypes::arrangeCall(const CGFunctionInfo &signature,
const CallArgList &args,
const FunctionDecl *ABIInfoFD) {
assert(signature.arg_size() <= args.size());
unsigned X86ABIAVXLevel =
CGM.getABIInfo().getX86ABIAVXLevel(ABIInfoFD, signature.getExtInfo());
if (signature.arg_size() == args.size() &&
signature.getX86ABIAVXLevel() == X86ABIAVXLevel)
return signature;
ExtParameterInfoList paramInfos;
auto sigParamInfos = signature.getExtParameterInfos();
if (!sigParamInfos.empty()) {
paramInfos.append(sigParamInfos.begin(), sigParamInfos.end());
paramInfos.resize(args.size());
}
CanQualTypeList argTypes = getArgTypesForCall(Context, args);
assert(signature.getRequiredArgs().allowsOptionalArgs());
FnInfoOpts opts = FnInfoOpts::None;
if (signature.isInstanceMethod())
opts |= FnInfoOpts::IsInstanceMethod;
if (signature.isChainCall())
opts |= FnInfoOpts::IsChainCall;
if (signature.isDelegateCall())
opts |= FnInfoOpts::IsDelegateCall;
const CGFunctionInfo *newFI = findOrInsertCGFunctionInfo(
signature.isInstanceMethod(), signature.isChainCall(),
signature.isDelegateCall(), X86ABIAVXLevel, signature.getExtInfo(),
paramInfos, signature.getRequiredArgs(), signature.getReturnType(),
argTypes);
return *newFI;
}
namespace clang {
namespace CodeGen {
void computeSPIRKernelABIInfo(CodeGenModule &CGM, CGFunctionInfo &FI);
} // namespace CodeGen
} // namespace clang
#ifndef NDEBUG
static const char *abiKindToString(ABIArgInfo::Kind K) {
switch (K) {
case ABIArgInfo::Direct:
return "Direct";
case ABIArgInfo::Extend:
return "Extend";
case ABIArgInfo::Indirect:
return "Indirect";
case ABIArgInfo::IndirectAliased:
return "IndirectAliased";
case ABIArgInfo::Ignore:
return "Ignore";
case ABIArgInfo::Expand:
return "Expand";
case ABIArgInfo::CoerceAndExpand:
return "CoerceAndExpand";
case ABIArgInfo::TargetSpecific:
return "TargetSpecific";
case ABIArgInfo::InAlloca:
return "InAlloca";
}
llvm_unreachable("Unknown kind");
}
#endif
void CodeGenModule::computeABIInfoUsingLib(CGFunctionInfo &FI) {
SmallVector<const llvm::abi::Type *> MappedArgTypes;
MappedArgTypes.reserve(FI.arg_size());
for (const auto &Arg : FI.arguments())
MappedArgTypes.push_back(AbiMapper->convertType(Arg.type));
RequiredArgs Required = FI.getRequiredArgs();
llvm::abi::RequiredArgs AbiRequired = llvm::abi::RequiredArgs::All;
if (Required.allowsOptionalArgs())
AbiRequired = llvm::abi::RequiredArgs(Required.getNumRequiredArgs());
auto AbiFI = llvm::abi::FunctionInfo::create(
FI.getCallingConvention(), AbiMapper->convertType(FI.getReturnType()),
MappedArgTypes, AbiRequired);
getLLVMABITargetInfo(AbiMapper->getTypeBuilder()).computeInfo(*AbiFI);
#ifndef NDEBUG
// With assertions enabled, also compute info using Clang ABI logic,
// so we can ensure the results are consistent.
getABIInfo().computeInfo(FI);
auto ConvertABIArgInfo = [&](ABIArgInfo &Target,
const llvm::abi::ArgInfo &AbiInfo, QualType Type,
int ArgNo) {
auto Check = [&](bool Cond, llvm::function_ref<void()> MessageFn) {
if (Cond)
return;
if (ArgNo == -1)
llvm::dbgs() << "For return value of type ";
else
llvm::dbgs() << "For argument " << ArgNo << " of type ";
llvm::dbgs() << Type << ": ";
MessageFn();
llvm::dbgs() << "\n";
abort();
};
auto CheckSimple = [&](auto TargetVal, auto ResVal, StringRef What) {
Check(TargetVal == ResVal, [&]() {
llvm::dbgs() << What << " mismatch (expected: " << TargetVal
<< ", given: " << ResVal << ")";
});
};
ABIArgInfo Res = convertABIArgInfo(AbiInfo, Type);
Check(Target.getKind() == Res.getKind(), [&]() {
llvm::dbgs() << "Kind mismatch (expected: "
<< abiKindToString(Target.getKind())
<< ", given: " << abiKindToString(Res.getKind()) << ")";
});
if (Res.canHaveCoerceToType()) {
// Normalize nullptr types.
llvm::Type *TargetType = Target.getCoerceToType();
llvm::Type *ResType = Res.getCoerceToType();
if (!TargetType)
TargetType = getTypes().ConvertType(Type);
if (!ResType)
ResType = getTypes().ConvertType(Type);
Check(TargetType == ResType, [&]() {
llvm::dbgs() << "CoerceToType mismatch (expected: " << *TargetType
<< ", given: " << *ResType << ")";
});
}
switch (Res.getKind()) {
case ABIArgInfo::Extend:
CheckSimple(Target.isSignExt(), Res.isSignExt(), "SignExt");
CheckSimple(Target.isZeroExt(), Res.isZeroExt(), "ZeroExt");
[[fallthrough]];
case ABIArgInfo::Direct:
CheckSimple(Target.getDirectAlign(), Res.getDirectAlign(), "DirectAlign");
CheckSimple(Target.getDirectOffset(), Res.getDirectOffset(),
"DirectOffset");
// Extend falls through to here, and only Direct carries the flag.
if (Res.isDirect())
CheckSimple(Target.getCanBeFlattened(), Res.getCanBeFlattened(),
"CanBeFlattened");
break;
case ABIArgInfo::Indirect:
CheckSimple(Target.getIndirectByVal(), Res.getIndirectByVal(),
"IndirectByVal");
[[fallthrough]];
case ABIArgInfo::IndirectAliased:
CheckSimple(Target.getIndirectAddrSpace(), Res.getIndirectAddrSpace(),
"IndirectAddrSpace");
CheckSimple(Target.getIndirectRealign(), Res.getIndirectRealign(),
"IndirectRealign");
Check(Target.getIndirectAlign() == Res.getIndirectAlign(), [&]() {
llvm::dbgs() << "IndirectAlign mismatch (expected: "
<< Target.getIndirectAlign().getQuantity()
<< ", given: " << Res.getIndirectAlign().getQuantity()
<< ")";
});
break;
case ABIArgInfo::CoerceAndExpand:
Check(Target.getUnpaddedCoerceAndExpandType() ==
Res.getUnpaddedCoerceAndExpandType(),
[&]() {
llvm::dbgs() << "UnpaddedCoerceAndExpandType mismatch (expected: "
<< *Target.getUnpaddedCoerceAndExpandType()
<< ", given: "
<< *Res.getUnpaddedCoerceAndExpandType() << ")";
});
break;
default:
break;
}
Target = Res;
};
#else
auto ConvertABIArgInfo =
[&](ABIArgInfo &Target, const llvm::abi::ArgInfo &AbiInfo, QualType Type,
int ArgNo) { Target = convertABIArgInfo(AbiInfo, Type); };
#endif
ConvertABIArgInfo(FI.getReturnInfo(), AbiFI->getReturnInfo(),
FI.getReturnType(), -1);
int ArgNo = 0;
for (auto [CGArg, AbiArg] :
llvm::zip_equal(FI.arguments(), AbiFI->arguments()))
ConvertABIArgInfo(CGArg.info, AbiArg.Info, CGArg.type, ArgNo++);
}
ABIArgInfo CodeGenModule::convertABIArgInfo(const llvm::abi::ArgInfo &AbiInfo,
QualType Type) {
switch (AbiInfo.getKind()) {
case llvm::abi::ArgInfo::Direct: {
llvm::Type *CoercedType = nullptr;
if (AbiInfo.getCoerceToType())
CoercedType = AbiReverseMapper->convertType(AbiInfo.getCoerceToType());
if (!CoercedType)
CoercedType = getTypes().ConvertType(Type);
unsigned DirectAlign = 0;
if (llvm::MaybeAlign Align = AbiInfo.getDirectAlign())
DirectAlign = Align->value();
// TODO: Move Padding into the ABIArgInfo struct when we add support for
// targets that need a different setting than we have here.
return ABIArgInfo::getDirect(CoercedType, AbiInfo.getDirectOffset(),
/*Padding=*/nullptr,
AbiInfo.getCanBeFlattened(), DirectAlign);
}
case llvm::abi::ArgInfo::Extend: {
llvm::Type *CoercedType = nullptr;
if (AbiInfo.getCoerceToType())
CoercedType = AbiReverseMapper->convertType(AbiInfo.getCoerceToType());
if (!CoercedType)
CoercedType = getTypes().ConvertType(Type);
// A transparent union is passed as its first field, so the extend keys off
// that field's integral type, matching the classifier's
// useFirstFieldIfTransparentUnion. Passing the union type to
// ABIArgInfo::getSignExtend would trip its integral-type assert.
QualType ExtendType = useFirstFieldIfTransparentUnion(Type);
if (AbiInfo.isSignExt())
return ABIArgInfo::getSignExtend(ExtendType, CoercedType);
if (AbiInfo.isZeroExt())
return ABIArgInfo::getZeroExtend(ExtendType, CoercedType);
return ABIArgInfo::getExtend(ExtendType, CoercedType);
}
case llvm::abi::ArgInfo::Indirect: {
CharUnits Alignment =
CharUnits::fromQuantity(AbiInfo.getIndirectAlign().value());
return ABIArgInfo::getIndirect(Alignment, AbiInfo.getIndirectAddrSpace(),
AbiInfo.getIndirectByVal(),
AbiInfo.getIndirectRealign());
}
case llvm::abi::ArgInfo::IndirectAliased: {
// Aliased indirect carries an address space but never byval.
CharUnits Alignment =
CharUnits::fromQuantity(AbiInfo.getIndirectAlign().value());
return ABIArgInfo::getIndirectAliased(Alignment,
AbiInfo.getIndirectAddrSpace(),
AbiInfo.getIndirectRealign());
}
case llvm::abi::ArgInfo::Ignore:
return ABIArgInfo::getIgnore();
case llvm::abi::ArgInfo::CoerceAndExpand: {
llvm::StructType *CoercedType = llvm::cast<llvm::StructType>(
AbiReverseMapper->convertType(AbiInfo.getCoerceToType()));
llvm::Type *UnpaddedType =
AbiReverseMapper->convertType(AbiInfo.getUnpaddedCoerceAndExpandType());
return ABIArgInfo::getCoerceAndExpand(CoercedType, UnpaddedType);
}
}
llvm_unreachable("Unexpected llvm::abi::ArgInfo kind");
}
/// 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, FnInfoOpts opts, ArrayRef<CanQualType> argTypes,
FunctionType::ExtInfo info,
ArrayRef<FunctionProtoType::ExtParameterInfo> paramInfos,
RequiredArgs required, const FunctionDecl *ABIInfoFD) {
assert(llvm::all_of(argTypes,
[](CanQualType T) { return T.isCanonicalAsParam(); }));
// Lookup or create unique function info.
bool isInstanceMethod =
(opts & FnInfoOpts::IsInstanceMethod) == FnInfoOpts::IsInstanceMethod;
bool isChainCall =
(opts & FnInfoOpts::IsChainCall) == FnInfoOpts::IsChainCall;
bool isDelegateCall =
(opts & FnInfoOpts::IsDelegateCall) == FnInfoOpts::IsDelegateCall;
unsigned X86ABIAVXLevel = CGM.getABIInfo().getX86ABIAVXLevel(ABIInfoFD, info);
const CGFunctionInfo *newFI = findOrInsertCGFunctionInfo(
isInstanceMethod, isChainCall, isDelegateCall, X86ABIAVXLevel, info,
paramInfos, required, resultType, argTypes);
return *newFI;
}
CGFunctionInfo *CodeGenTypes::findOrInsertCGFunctionInfo(
bool isInstanceMethod, bool isChainCall, bool isDelegateCall,
unsigned X86ABIAVXLevel, const FunctionType::ExtInfo &info,
ArrayRef<FunctionProtoType::ExtParameterInfo> paramInfos,
RequiredArgs required, CanQualType resultType,
ArrayRef<CanQualType> argTypes) {
llvm::FoldingSetNodeID ID;
CGFunctionInfo::Profile(ID, isInstanceMethod, isChainCall, isDelegateCall,
X86ABIAVXLevel, info, paramInfos, required,
resultType, argTypes);
llvm::FoldingSetInsertToken InsertToken;
CGFunctionInfo *FI = FunctionInfos.lookup(ID, InsertToken);
if (FI)
return FI;
unsigned CC = ClangCallConvToLLVMCallConv(info.getCC());
// Construct the function info. We co-allocate the ArgInfos.
FI = CGFunctionInfo::create(CC, isInstanceMethod, isChainCall, isDelegateCall,
X86ABIAVXLevel, info, paramInfos, resultType,
argTypes, required);
FunctionInfos.insert(FI, InsertToken);
bool inserted = FunctionsBeingProcessed.insert(FI).second;
(void)inserted;
assert(inserted && "Recursively being processed?");
// Compute ABI information.
if (info.getCC() == CC_DeviceKernel &&
(CC == llvm::CallingConv::SPIR_KERNEL || CC == llvm::CallingConv::C)) {
// Force target independent argument handling for the host visible
// kernel functions.
//
// For CPU targets, this currently only works for OpenCL.
assert(CC != llvm::CallingConv::C || getContext().getLangOpts().OpenCL);
// SPIR-V lowers OpenCL types to target extension types, which the ABI
// library cannot tell apart from the kernel pointers it coerces yet, so
// such kernels keep Clang's own lowering.
auto IsSPIRVOpenCLType = [&](const CGFunctionInfoArgInfo &Arg) {
return CGM.getTriple().isSPIRV() &&
Arg.type.getTypePtr()->isOpenCLSpecificType();
};
if (CC == llvm::CallingConv::SPIR_KERNEL &&
CGM.shouldUseLLVMABILowering(CC) &&
llvm::none_of(FI->arguments(), IsSPIRVOpenCLType))
CGM.computeABIInfoUsingLib(*FI);
else
computeSPIRKernelABIInfo(CGM, *FI);
} else if (info.getCC() == CC_Swift || info.getCC() == CC_SwiftAsync) {
swiftcall::computeABIInfo(CGM, *FI);
} else if (CGM.shouldUseLLVMABILowering(CC)) {
CGM.computeABIInfoUsingLib(*FI);
} else {
CGM.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, bool delegateCall,
unsigned X86ABIAVXLevel, 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->DelegateCall = delegateCall;
FI->CmseNSCall = info.getCmseNSCall();
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->X86ABIAVXLevel = X86ABIAVXLevel;
FI->ArgStruct = nullptr;
FI->ArgStructAlign = 0;
FI->NumArgs = argTypes.size();
FI->HasExtParameterInfos = !paramInfos.empty();
FI->getArgsBuffer()[0].type = resultType;
FI->MaxVectorWidth = 0;
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->getZExtSize());
}
if (const auto *RD = Ty->getAsRecordDecl()) {
SmallVector<const CXXBaseSpecifier *, 1> Bases;
SmallVector<const FieldDecl *, 1> Fields;
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())
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");
llvm::append_range(Bases, llvm::make_pointer_range(CXXRD->bases()));
}
for (const auto *FD : RD->fields()) {
if (FD->isZeroLengthBitField())
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) {
for (int i = 0, n = CAE->NumElts; i < n; i++) {
Address EltAddr = CGF.Builder.CreateConstGEP2_32(BaseAddr, 0, i);
Fn(EltAddr);
}
}
void CodeGenFunction::ExpandTypeFromArgs(QualType Ty, LValue LV,
llvm::Function::arg_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 {
// Call EmitStoreOfScalar except when the lvalue is a bitfield to emit a
// primitive store.
assert(isa<NoExpansion>(Exp.get()));
llvm::Value *Arg = &*AI++;
if (LV.isBitField()) {
EmitStoreThroughLValue(RValue::get(Arg), LV);
} else {
// TODO: currently there are some places are inconsistent in what LLVM
// pointer type they use (see D118744). Once clang uses opaque pointers
// all LLVM pointer types will be the same and we can remove this check.
if (Arg->getType()->isPointerTy()) {
Address Addr = LV.getAddress();
Arg = Builder.CreateBitCast(Arg, Addr.getElementType());
}
EmitStoreOfScalar(Arg, 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 RawAddress CreateTempAllocaForCoercion(CodeGenFunction &CGF,
llvm::Type *Ty,
CharUnits MinAlign,
const Twine &Name = "tmp") {
// Don't use an alignment that's worse than what LLVM would prefer.
auto PrefAlign = CGF.CGM.getDataLayout().getPrefTypeAlign(Ty);
CharUnits Align = std::max(MinAlign, CharUnits::fromQuantity(PrefAlign));
return CGF.CreateTempAlloca(Ty, Align, Name + ".coerce");
}
/// 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;
}
static llvm::Value *CreatePFPCoercedLoad(Address Src, QualType SrcFETy,
llvm::Type *Ty, CodeGenFunction &CGF) {
std::vector<PFPField> PFPFields = CGF.getContext().findPFPFields(SrcFETy);
if (PFPFields.empty())
return nullptr;
auto LoadCoercedField = [&](CharUnits Offset,
llvm::Type *FieldType) -> llvm::Value * {
// Check whether the field at Offset is a PFP field. This function is called
// in ascending order of offset, and PFPFields is sorted by offset. This
// means that we only need to check the first element (and remove it from
// PFPFields if matching).
if (!PFPFields.empty() && PFPFields[0].Offset == Offset) {
auto FieldAddr = CGF.EmitAddressOfPFPField(Src, PFPFields[0]);
llvm::Value *FieldVal = CGF.Builder.CreateLoad(FieldAddr);
if (isa<llvm::IntegerType>(FieldType))
FieldVal = CGF.Builder.CreatePtrToInt(FieldVal, FieldType);
PFPFields.erase(PFPFields.begin());
return FieldVal;
}
auto FieldAddr =
CGF.Builder
.CreateConstInBoundsByteGEP(Src.withElementType(CGF.Int8Ty), Offset)
.withElementType(FieldType);
return CGF.Builder.CreateLoad(FieldAddr);
};
// The types handled by this function are the only ones that may be generated
// by AArch64ABIInfo::classify{Argument,Return}Type for struct types with
// pointers. PFP is only supported on AArch64.
if (isa<llvm::IntegerType>(Ty) || isa<llvm::PointerType>(Ty)) {
auto Addr = CGF.EmitAddressOfPFPField(Src, PFPFields[0]);
llvm::Value *Val = CGF.Builder.CreateLoad(Addr);
if (isa<llvm::IntegerType>(Ty))
Val = CGF.Builder.CreatePtrToInt(Val, Ty);
return Val;
}
auto *AT = cast<llvm::ArrayType>(Ty);
auto *ET = AT->getElementType();
CharUnits WordSize = CGF.getContext().toCharUnitsFromBits(
CGF.CGM.getDataLayout().getTypeSizeInBits(ET));
CharUnits Offset = CharUnits::Zero();
llvm::Value *Val = llvm::PoisonValue::get(AT);
for (unsigned Idx = 0; Idx != AT->getNumElements(); ++Idx, Offset += WordSize)
Val = CGF.Builder.CreateInsertValue(Val, LoadCoercedField(Offset, ET), Idx);
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, QualType SrcFETy,
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);
if (llvm::Value *V = CreatePFPCoercedLoad(Src, SrcFETy, Ty, CGF))
return V;
llvm::TypeSize DstSize = CGF.CGM.getDataLayout().getTypeAllocSize(Ty);
if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy)) {
Src = EnterStructPointerForCoercedAccess(Src, SrcSTy,
DstSize.getFixedValue(), CGF);
SrcTy = Src.getElementType();
}
llvm::TypeSize 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.isScalable() && !DstSize.isScalable() &&
SrcSize.getFixedValue() >= DstSize.getFixedValue()) {
// 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 = Src.withElementType(Ty);
return CGF.Builder.CreateLoad(Src);
}
// If coercing a fixed vector to a scalable vector for ABI compatibility, and
// the types match, use the llvm.vector.insert intrinsic to perform the
// conversion.
if (auto *ScalableDstTy = dyn_cast<llvm::ScalableVectorType>(Ty)) {
if (auto *FixedSrcTy = dyn_cast<llvm::FixedVectorType>(SrcTy)) {
// If we are casting a fixed i8 vector to a scalable i1 predicate
// vector, use a vector insert and bitcast the result.
if (ScalableDstTy->getElementType()->isIntegerTy(1) &&
FixedSrcTy->getElementType()->isIntegerTy(8)) {
ScalableDstTy = llvm::ScalableVectorType::get(
FixedSrcTy->getElementType(),
llvm::divideCeil(
ScalableDstTy->getElementCount().getKnownMinValue(), 8));
}
if (ScalableDstTy->getElementType() == FixedSrcTy->getElementType()) {
auto *Load = CGF.Builder.CreateLoad(Src);
auto *PoisonVec = llvm::PoisonValue::get(ScalableDstTy);
llvm::Value *Result = CGF.Builder.CreateInsertVector(
ScalableDstTy, PoisonVec, Load, uint64_t(0), "cast.scalable");
ScalableDstTy = cast<llvm::ScalableVectorType>(
llvm::VectorType::getWithSizeAndScalar(ScalableDstTy, Ty));
if (Result->getType() != ScalableDstTy)
Result = CGF.Builder.CreateBitCast(Result, ScalableDstTy);
if (Result->getType() != Ty)
Result = CGF.Builder.CreateExtractVector(Ty, Result, uint64_t(0));
return Result;
}
}
}
// Otherwise do coercion through memory. This is stupid, but simple.
RawAddress Tmp =
CreateTempAllocaForCoercion(CGF, Ty, Src.getAlignment(), Src.getName());
CGF.Builder.CreateMemCpy(
Tmp.getPointer(), Tmp.getAlignment().getAsAlign(),
Src.emitRawPointer(CGF), Src.getAlignment().getAsAlign(),
llvm::ConstantInt::get(CGF.IntPtrTy, SrcSize.getKnownMinValue()));
return CGF.Builder.CreateLoad(Tmp);
}
static bool CreatePFPCoercedStore(llvm::Value *Src, QualType SrcFETy,
Address Dst, CodeGenFunction &CGF) {
std::vector<PFPField> PFPFields = CGF.getContext().findPFPFields(SrcFETy);
if (PFPFields.empty())
return false;
llvm::Type *SrcTy = Src->getType();
auto StoreCoercedField = [&](CharUnits Offset, llvm::Value *FieldVal) {
if (!PFPFields.empty() && PFPFields[0].Offset == Offset) {
auto FieldAddr = CGF.EmitAddressOfPFPField(Dst, PFPFields[0]);
if (isa<llvm::IntegerType>(FieldVal->getType()))
FieldVal = CGF.Builder.CreateIntToPtr(FieldVal, CGF.VoidPtrTy);
CGF.Builder.CreateStore(FieldVal, FieldAddr);
PFPFields.erase(PFPFields.begin());
} else {
auto FieldAddr = CGF.Builder
.CreateConstInBoundsByteGEP(
Dst.withElementType(CGF.Int8Ty), Offset)
.withElementType(FieldVal->getType());
CGF.Builder.CreateStore(FieldVal, FieldAddr);
}
};
// The types handled by this function are the only ones that may be generated
// by AArch64ABIInfo::classify{Argument,Return}Type for struct types with
// pointers. PFP is only supported on AArch64.
if (isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy)) {
if (isa<llvm::IntegerType>(SrcTy))
Src = CGF.Builder.CreateIntToPtr(Src, CGF.VoidPtrTy);
auto Addr = CGF.EmitAddressOfPFPField(Dst, PFPFields[0]);
CGF.Builder.CreateStore(Src, Addr);
} else {
auto *AT = cast<llvm::ArrayType>(SrcTy);
auto *ET = AT->getElementType();
CharUnits WordSize = CGF.getContext().toCharUnitsFromBits(
CGF.CGM.getDataLayout().getTypeSizeInBits(ET));
CharUnits Offset = CharUnits::Zero();
for (unsigned i = 0; i != AT->getNumElements(); ++i, Offset += WordSize)
StoreCoercedField(Offset, CGF.Builder.CreateExtractValue(Src, i));
}
return true;
}
void CodeGenFunction::CreateCoercedStore(llvm::Value *Src, QualType SrcFETy,
Address Dst, llvm::TypeSize DstSize,
bool DstIsVolatile) {
if (!DstSize)
return;
llvm::Type *SrcTy = Src->getType();
llvm::TypeSize SrcSize = CGM.getDataLayout().getTypeAllocSize(SrcTy);
// GEP into structs to try to make types match.
// FIXME: This isn't really that useful with opaque types, but it impacts a
// lot of regression tests.
if (SrcTy != Dst.getElementType()) {
if (llvm::StructType *DstSTy =
dyn_cast<llvm::StructType>(Dst.getElementType())) {
assert(!SrcSize.isScalable());
Dst = EnterStructPointerForCoercedAccess(Dst, DstSTy,
SrcSize.getFixedValue(), *this);
}
}
if (CreatePFPCoercedStore(Src, SrcFETy, Dst, *this))
return;
if (SrcSize.isScalable() || SrcSize <= DstSize) {
if (SrcTy->isIntegerTy() && Dst.getElementType()->isPointerTy() &&
SrcSize == CGM.getDataLayout().getTypeAllocSize(Dst.getElementType())) {
// If the value is supposed to be a pointer, convert it before storing it.
Src = CoerceIntOrPtrToIntOrPtr(Src, Dst.getElementType(), *this);
auto *I = Builder.CreateStore(Src, Dst, DstIsVolatile);
addInstToCurrentSourceAtom(I, Src);
} else if (llvm::StructType *STy =
dyn_cast<llvm::StructType>(Src->getType())) {
// Prefer scalar stores to first-class aggregate stores.
Dst = Dst.withElementType(SrcTy);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
Address EltPtr = Builder.CreateStructGEP(Dst, i);
llvm::Value *Elt = Builder.CreateExtractValue(Src, i);
auto *I = Builder.CreateStore(Elt, EltPtr, DstIsVolatile);
addInstToCurrentSourceAtom(I, Elt);
}
} else {
auto *I =
Builder.CreateStore(Src, Dst.withElementType(SrcTy), DstIsVolatile);
addInstToCurrentSourceAtom(I, Src);
}
} else if (SrcTy->isIntegerTy()) {
// If the source is a simple integer, coerce it directly.
llvm::Type *DstIntTy = Builder.getIntNTy(DstSize.getFixedValue() * 8);
Src = CoerceIntOrPtrToIntOrPtr(Src, DstIntTy, *this);
auto *I =
Builder.CreateStore(Src, Dst.withElementType(DstIntTy), DstIsVolatile);
addInstToCurrentSourceAtom(I, Src);
} 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.
RawAddress Tmp =
CreateTempAllocaForCoercion(*this, SrcTy, Dst.getAlignment());
Builder.CreateStore(Src, Tmp);
auto *I = Builder.CreateMemCpy(
Dst.emitRawPointer(*this), Dst.getAlignment().getAsAlign(),
Tmp.getPointer(), Tmp.getAlignment().getAsAlign(),
Builder.CreateTypeSize(IntPtrTy, DstSize));
addInstToCurrentSourceAtom(I, Src);
}
}
static Address emitAddressAtOffset(CodeGenFunction &CGF, Address addr,
const ABIArgInfo &info) {
if (unsigned offset = info.getDirectOffset()) {
addr = addr.withElementType(CGF.Int8Ty);
addr = CGF.Builder.CreateConstInBoundsByteGEP(
addr, CharUnits::fromQuantity(offset));
addr = addr.withElementType(info.getCoerceToType());
}
return addr;
}
static std::pair<llvm::Value *, bool>
CoerceScalableToFixed(CodeGenFunction &CGF, llvm::FixedVectorType *ToTy,
llvm::ScalableVectorType *FromTy, llvm::Value *V,
StringRef Name = "") {
// If we are casting a scalable i1 predicate vector to a fixed i8
// vector, first bitcast the source.
if (FromTy->getElementType()->isIntegerTy(1) &&
ToTy->getElementType() == CGF.Builder.getInt8Ty()) {
if (!FromTy->getElementCount().isKnownMultipleOf(8)) {
FromTy = llvm::ScalableVectorType::get(
FromTy->getElementType(),
llvm::alignTo<8>(FromTy->getElementCount().getKnownMinValue()));
llvm::Value *ZeroVec = llvm::Constant::getNullValue(FromTy);
V = CGF.Builder.CreateInsertVector(FromTy, ZeroVec, V, uint64_t(0));
}
FromTy = llvm::ScalableVectorType::get(
ToTy->getElementType(),
FromTy->getElementCount().getKnownMinValue() / 8);
V = CGF.Builder.CreateBitCast(V, FromTy);
}
if (FromTy->getElementType() == ToTy->getElementType()) {
V->setName(Name + ".coerce");
V = CGF.Builder.CreateExtractVector(ToTy, V, uint64_t(0), "cast.fixed");
return {V, true};
}
return {V, false};
}
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::TargetSpecific:
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:
case ABIArgInfo::IndirectAliased:
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::ReturnTypeHasInReg(const CGFunctionInfo &FI) {
const auto &RI = FI.getReturnInfo();
return RI.getInReg();
}
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(FloatModeKind::Float);
case BuiltinType::Double:
return getTarget().useObjCFPRetForRealType(FloatModeKind::Double);
case BuiltinType::LongDouble:
return getTarget().useObjCFPRetForRealType(FloatModeKind::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:
case ABIArgInfo::IndirectAliased:
llvm_unreachable("Invalid ABI kind for return argument");
case ABIArgInfo::TargetSpecific:
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();
unsigned addressSpace = CGM.getTypes().getTargetAddressSpace(ret);
resultType = llvm::PointerType::get(getLLVMContext(), 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()) {
ArgTypes[IRFunctionArgs.getSRetArgNo()] = llvm::PointerType::get(
getLLVMContext(), FI.getReturnInfo().getIndirectAddrSpace());
}
// Add type for inalloca argument.
if (IRFunctionArgs.hasInallocaArg())
ArgTypes[IRFunctionArgs.getInallocaArgNo()] =
llvm::PointerType::getUnqual(getLLVMContext());
// 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.
ArgTypes[FirstIRArg] = llvm::PointerType::get(
getLLVMContext(), CGM.getDataLayout().getAllocaAddrSpace());
break;
case ABIArgInfo::IndirectAliased:
assert(NumIRArgs == 1);
ArgTypes[FirstIRArg] = llvm::PointerType::get(
getLLVMContext(), ArgInfo.getIndirectAddrSpace());
break;
case ABIArgInfo::TargetSpecific:
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()->castAs<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);
unsigned SMEBits = FPT->getAArch64SMEAttributes();
if (SMEBits & FunctionType::SME_PStateSMEnabledMask)
FuncAttrs.addAttribute("aarch64_pstate_sm_enabled");
if (SMEBits & FunctionType::SME_PStateSMCompatibleMask)
FuncAttrs.addAttribute("aarch64_pstate_sm_compatible");
if (SMEBits & FunctionType::SME_AgnosticZAStateMask)
FuncAttrs.addAttribute("aarch64_za_state_agnostic");
// ZA
if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_Preserves)
FuncAttrs.addAttribute("aarch64_preserves_za");
if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_In)
FuncAttrs.addAttribute("aarch64_in_za");
if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_Out)
FuncAttrs.addAttribute("aarch64_out_za");
if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_InOut)
FuncAttrs.addAttribute("aarch64_inout_za");
// ZT0
if (FunctionType::getArmZT0State(SMEBits) == FunctionType::ARM_Preserves)
FuncAttrs.addAttribute("aarch64_preserves_zt0");
if (FunctionType::getArmZT0State(SMEBits) == FunctionType::ARM_In)
FuncAttrs.addAttribute("aarch64_in_zt0");
if (FunctionType::getArmZT0State(SMEBits) == FunctionType::ARM_Out)
FuncAttrs.addAttribute("aarch64_out_zt0");
if (FunctionType::getArmZT0State(SMEBits) == FunctionType::ARM_InOut)
FuncAttrs.addAttribute("aarch64_inout_zt0");
unsigned RISCVBits = FPT->getRISCVAttributes();
switch (FunctionType::getRISCVXsfmmState(RISCVBits)) {
case FunctionType::RISCVNone:
break;
case FunctionType::RISCVIn:
FuncAttrs.addAttribute("riscv_in");
break;
case FunctionType::RISCVOut:
FuncAttrs.addAttribute("riscv_out");
break;
case FunctionType::RISCVInOut:
FuncAttrs.addAttribute("riscv_inout");
break;
case FunctionType::RISCVPreserves:
FuncAttrs.addAttribute("riscv_preserves");
break;
case FunctionType::RISCVNew:
FuncAttrs.addAttribute("riscv_new");
break;
}
}
static void AddAttributesFromOMPAssumes(llvm::AttrBuilder &FuncAttrs,
const Decl *Callee) {
if (!Callee)
return;
SmallVector<StringRef, 4> Attrs;
for (const OMPAssumeAttr *AA : Callee->specific_attrs<OMPAssumeAttr>())
AA->getAssumption().split(Attrs, ",");
if (!Attrs.empty())
FuncAttrs.addAttribute(llvm::AssumptionAttrKey,
llvm::join(Attrs.begin(), Attrs.end(), ","));
}
bool CodeGenModule::MayDropFunctionReturn(const ASTContext &Context,
QualType ReturnType) const {
// We can't just discard the return value for a record type with a
// complex destructor or a non-trivially copyable type.
if (const RecordType *RT =
ReturnType.getCanonicalType()->getAsCanonical<RecordType>()) {
if (const auto *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl()))
return ClassDecl->hasTrivialDestructor();
}
return ReturnType.isTriviallyCopyableType(Context);
}
static bool HasStrictReturn(const CodeGenModule &Module, QualType RetTy,
const Decl *TargetDecl) {
// As-is msan can not tolerate noundef mismatch between caller and
// implementation. Mismatch is possible for e.g. indirect calls from C-caller
// into C++. Such mismatches lead to confusing false reports. To avoid
// expensive workaround on msan we enforce initialization event in uncommon
// cases where it's allowed.
if (Module.getLangOpts().Sanitize.has(SanitizerKind::Memory))
return true;
// C++ explicitly makes returning undefined values UB. C's rule only applies
// to used values, so we never mark them noundef for now.
if (!Module.getLangOpts().CPlusPlus)
return false;
if (TargetDecl) {
if (const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(TargetDecl)) {
if (FDecl->isExternC())
return false;
} else if (const VarDecl *VDecl = dyn_cast<VarDecl>(TargetDecl)) {
// Function pointer.
if (VDecl->isExternC())
return false;
}
}
// We don't want to be too aggressive with the return checking, unless
// it's explicit in the code opts or we're using an appropriate sanitizer.
// Try to respect what the programmer intended.
return Module.getCodeGenOpts().StrictReturn ||
!Module.MayDropFunctionReturn(Module.getContext(), RetTy) ||
Module.getLangOpts().Sanitize.has(SanitizerKind::Return);
}
/// Add denormal-fp-math and denormal-fp-math-f32 as appropriate for the
/// requested denormal behavior, accounting for the overriding behavior of the
/// -f32 case.
static void addDenormalModeAttrs(llvm::DenormalMode FPDenormalMode,
llvm::DenormalMode FP32DenormalMode,
llvm::AttrBuilder &FuncAttrs) {
llvm::DenormalFPEnv FPEnv(FPDenormalMode, FP32DenormalMode);
if (FPEnv != llvm::DenormalFPEnv::getDefault())
FuncAttrs.addDenormalFPEnvAttr(FPEnv);
}
/// Add default attributes to a function, which have merge semantics under
/// -mlink-builtin-bitcode and should not simply overwrite any existing
/// attributes in the linked library.
static void
addMergableDefaultFunctionAttributes(const CodeGenOptions &CodeGenOpts,
llvm::AttrBuilder &FuncAttrs) {
addDenormalModeAttrs(CodeGenOpts.FPDenormalMode, CodeGenOpts.FP32DenormalMode,
FuncAttrs);
}
static void getTrivialDefaultFunctionAttributes(
StringRef Name, bool HasOptnone, const CodeGenOptions &CodeGenOpts,
const LangOptions &LangOpts, 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.
// FIXME: Look for 'BuiltinAttr' on the function rather than re-checking
// the -fno-builtin-foo list.
if (!CodeGenOpts.SimplifyLibCalls || LangOpts.isNoBuiltinFunc(Name))
FuncAttrs.addAttribute(llvm::Attribute::NoBuiltin);
if (!CodeGenOpts.TrapFuncName.empty())
FuncAttrs.addAttribute("trap-func-name", CodeGenOpts.TrapFuncName);
} else {
switch (CodeGenOpts.getFramePointer()) {
case CodeGenOptions::FramePointerKind::None:
// This is the default behavior.
break;
case CodeGenOptions::FramePointerKind::Reserved:
case CodeGenOptions::FramePointerKind::NonLeafNoReserve:
case CodeGenOptions::FramePointerKind::NonLeaf:
case CodeGenOptions::FramePointerKind::All:
FuncAttrs.addAttribute("frame-pointer",
CodeGenOptions::getFramePointerKindName(
CodeGenOpts.getFramePointer()));
}
if (CodeGenOpts.LessPreciseFPMAD)
FuncAttrs.addAttribute("less-precise-fpmad", "true");
if (CodeGenOpts.NullPointerIsValid)
FuncAttrs.addAttribute(llvm::Attribute::NullPointerIsValid);
if (LangOpts.getDefaultExceptionMode() == LangOptions::FPE_Ignore)
FuncAttrs.addAttribute("no-trapping-math", "true");
// TODO: Are these all needed?
// unsafe/inf/nan/nsz are handled by instruction-level FastMathFlags.
if (CodeGenOpts.SoftFloat)
FuncAttrs.addAttribute("use-soft-float", "true");
FuncAttrs.addAttribute("stack-protector-buffer-size",
llvm::utostr(CodeGenOpts.SSPBufferSize));
if (LangOpts.NoSignedZero)
FuncAttrs.addAttribute("no-signed-zeros-fp-math", "true");
// 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.EnableSegmentedStacks)
FuncAttrs.addAttribute("split-stack");
if (CodeGenOpts.SpeculativeLoadHardening)
FuncAttrs.addAttribute(llvm::Attribute::SpeculativeLoadHardening);
// Add zero-call-used-regs attribute.
switch (CodeGenOpts.getZeroCallUsedRegs()) {
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::Skip:
FuncAttrs.removeAttribute("zero-call-used-regs");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::UsedGPRArg:
FuncAttrs.addAttribute("zero-call-used-regs", "used-gpr-arg");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::UsedGPR:
FuncAttrs.addAttribute("zero-call-used-regs", "used-gpr");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::UsedArg:
FuncAttrs.addAttribute("zero-call-used-regs", "used-arg");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::Used:
FuncAttrs.addAttribute("zero-call-used-regs", "used");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::AllGPRArg:
FuncAttrs.addAttribute("zero-call-used-regs", "all-gpr-arg");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::AllGPR:
FuncAttrs.addAttribute("zero-call-used-regs", "all-gpr");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::AllArg:
FuncAttrs.addAttribute("zero-call-used-regs", "all-arg");
break;
case llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::All:
FuncAttrs.addAttribute("zero-call-used-regs", "all");
break;
}
}
if (LangOpts.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);
}
// TODO: NoUnwind attribute should be added for other GPU modes HIP,
// OpenMP offload. AFAIK, neither of them support exceptions in device code.
if ((LangOpts.CUDA && LangOpts.CUDAIsDevice) || LangOpts.OpenCL ||
LangOpts.SYCLIsDevice) {
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
}
if (CodeGenOpts.SaveRegParams && !AttrOnCallSite)
FuncAttrs.addAttribute("save-reg-params");
for (StringRef Attr : CodeGenOpts.DefaultFunctionAttrs) {
StringRef Var, Value;
std::tie(Var, Value) = Attr.split('=');
FuncAttrs.addAttribute(Var, Value);
}
if (!AttrOnCallSite) {
TargetInfo::BranchProtectionInfo BPI(LangOpts);
TargetCodeGenInfo::initBranchProtectionFnAttributes(BPI, FuncAttrs);
}
}
/// Merges `target-features` from \TargetOpts and \F, and sets the result in
/// \FuncAttr
/// * features from \F are always kept
/// * a feature from \TargetOpts is kept if itself and its opposite are absent
/// from \F
static void
overrideFunctionFeaturesWithTargetFeatures(llvm::AttrBuilder &FuncAttr,
const llvm::Function &F,
const TargetOptions &TargetOpts) {
auto FFeatures = F.getFnAttribute("target-features");
llvm::StringSet<> MergedNames;
SmallVector<StringRef> MergedFeatures;
MergedFeatures.reserve(TargetOpts.Features.size());
auto AddUnmergedFeatures = [&](auto &&FeatureRange) {
for (StringRef Feature : FeatureRange) {
if (Feature.empty())
continue;
assert(Feature[0] == '+' || Feature[0] == '-');
StringRef Name = Feature.drop_front(1);
bool Merged = !MergedNames.insert(Name).second;
if (!Merged)
MergedFeatures.push_back(Feature);
}
};
if (FFeatures.isValid())
AddUnmergedFeatures(llvm::split(FFeatures.getValueAsString(), ','));
AddUnmergedFeatures(TargetOpts.Features);
if (!MergedFeatures.empty()) {
llvm::sort(MergedFeatures);
FuncAttr.addAttribute("target-features", llvm::join(MergedFeatures, ","));
}
}
void CodeGen::mergeDefaultFunctionDefinitionAttributes(
llvm::Function &F, const CodeGenOptions &CodeGenOpts,
const LangOptions &LangOpts, const TargetOptions &TargetOpts,
bool WillInternalize) {
llvm::AttrBuilder FuncAttrs(F.getContext());
// Here we only extract the options that are relevant compared to the version
// from GetCPUAndFeaturesAttributes.
if (!TargetOpts.CPU.empty())
FuncAttrs.addAttribute("target-cpu", TargetOpts.CPU);
if (!TargetOpts.TuneCPU.empty())
FuncAttrs.addAttribute("tune-cpu", TargetOpts.TuneCPU);
::getTrivialDefaultFunctionAttributes(F.getName(), F.hasOptNone(),
CodeGenOpts, LangOpts,
/*AttrOnCallSite=*/false, FuncAttrs);
if (!WillInternalize && F.isInterposable()) {
// Do not promote "dynamic" denormal-fp-math to this translation unit's
// setting for weak functions that won't be internalized. The user has no
// real control for how builtin bitcode is linked, so we shouldn't assume
// later copies will use a consistent mode.
F.addFnAttrs(FuncAttrs);
return;
}
llvm::AttributeMask AttrsToRemove;
llvm::DenormalFPEnv OptsFPEnv(CodeGenOpts.FPDenormalMode,
CodeGenOpts.FP32DenormalMode);
llvm::DenormalFPEnv MergedFPEnv =
OptsFPEnv.mergeCalleeMode(F.getDenormalFPEnv());
if (MergedFPEnv == llvm::DenormalFPEnv::getDefault()) {
AttrsToRemove.addAttribute(llvm::Attribute::DenormalFPEnv);
} else {
// Overwrite existing attribute
FuncAttrs.addDenormalFPEnvAttr(MergedFPEnv);
}
F.removeFnAttrs(AttrsToRemove);
overrideFunctionFeaturesWithTargetFeatures(FuncAttrs, F, TargetOpts);
F.addFnAttrs(FuncAttrs);
}
void CodeGenModule::getTrivialDefaultFunctionAttributes(
StringRef Name, bool HasOptnone, bool AttrOnCallSite,
llvm::AttrBuilder &FuncAttrs) {
::getTrivialDefaultFunctionAttributes(Name, HasOptnone, getCodeGenOpts(),
getLangOpts(), AttrOnCallSite,
FuncAttrs);
}
void CodeGenModule::getDefaultFunctionAttributes(StringRef Name,
bool HasOptnone,
bool AttrOnCallSite,
llvm::AttrBuilder &FuncAttrs) {
getTrivialDefaultFunctionAttributes(Name, HasOptnone, AttrOnCallSite,
FuncAttrs);
if (!AttrOnCallSite)
TargetCodeGenInfo::initPointerAuthFnAttributes(CodeGenOpts.PointerAuth,
FuncAttrs);
// If we're just getting the default, get the default values for mergeable
// attributes.
if (!AttrOnCallSite)
addMergableDefaultFunctionAttributes(CodeGenOpts, FuncAttrs);
}
void CodeGenModule::addDefaultFunctionDefinitionAttributes(
llvm::AttrBuilder &attrs) {
getDefaultFunctionAttributes(/*function name*/ "", /*optnone*/ false,
/*for call*/ false, attrs);
GetCPUAndFeaturesAttributes(GlobalDecl(), attrs);
}
static void addNoBuiltinAttributes(llvm::AttrBuilder &FuncAttrs,
const LangOptions &LangOpts,
const NoBuiltinAttr *NBA = nullptr) {
auto AddNoBuiltinAttr = [&FuncAttrs](StringRef BuiltinName) {
SmallString<32> AttributeName;
AttributeName += "no-builtin-";
AttributeName += BuiltinName;
FuncAttrs.addAttribute(AttributeName);
};
// First, handle the language options passed through -fno-builtin.
if (LangOpts.NoBuiltin) {
// -fno-builtin disables them all.
FuncAttrs.addAttribute("no-builtins");
return;
}
// Then, add attributes for builtins specified through -fno-builtin-<name>.
llvm::for_each(LangOpts.NoBuiltinFuncs, AddNoBuiltinAttr);
// Now, let's check the __attribute__((no_builtin("...")) attribute added to
// the source.
if (!NBA)
return;
// If there is a wildcard in the builtin names specified through the
// attribute, disable them all.
if (llvm::is_contained(NBA->builtinNames(), "*")) {
FuncAttrs.addAttribute("no-builtins");
return;
}
// And last, add the rest of the builtin names.
llvm::for_each(NBA->builtinNames(), AddNoBuiltinAttr);
}
static bool DetermineNoUndef(QualType QTy, CodeGenTypes &Types,
const llvm::DataLayout &DL, const ABIArgInfo &AI,
bool CheckCoerce = true) {
llvm::Type *Ty = Types.ConvertTypeForMem(QTy);
if (AI.getKind() == ABIArgInfo::Indirect ||
AI.getKind() == ABIArgInfo::IndirectAliased)
return true;
if (AI.getKind() == ABIArgInfo::Extend && !AI.isNoExt())
return true;
if (!DL.typeSizeEqualsStoreSize(Ty))
// TODO: This will result in a modest amount of values not marked noundef
// when they could be. We care about values that *invisibly* contain undef
// bits from the perspective of LLVM IR.
return false;
if (CheckCoerce && AI.canHaveCoerceToType()) {
llvm::Type *CoerceTy = AI.getCoerceToType();
if (llvm::TypeSize::isKnownGT(DL.getTypeSizeInBits(CoerceTy),
DL.getTypeSizeInBits(Ty)))
// If we're coercing to a type with a greater size than the canonical one,
// we're introducing new undef bits.
// Coercing to a type of smaller or equal size is ok, as we know that
// there's no internal padding (typeSizeEqualsStoreSize).
return false;
}
if (QTy->isBitIntType())
return true;
if (QTy->isReferenceType())
return true;
if (QTy->isNullPtrType())
return false;
if (QTy->isMemberPointerType())
// TODO: Some member pointers are `noundef`, but it depends on the ABI. For
// now, never mark them.
return false;
if (QTy->isScalarType()) {
if (const ComplexType *Complex = dyn_cast<ComplexType>(QTy))
return DetermineNoUndef(Complex->getElementType(), Types, DL, AI, false);
return true;
}
if (const VectorType *Vector = dyn_cast<VectorType>(QTy))
return DetermineNoUndef(Vector->getElementType(), Types, DL, AI, false);
if (const MatrixType *Matrix = dyn_cast<MatrixType>(QTy))
return DetermineNoUndef(Matrix->getElementType(), Types, DL, AI, false);
if (const ArrayType *Array = dyn_cast<ArrayType>(QTy))
return DetermineNoUndef(Array->getElementType(), Types, DL, AI, false);
// TODO: Some structs may be `noundef`, in specific situations.
return false;
}
/// Check if the argument of a function has maybe_undef attribute.
static bool IsArgumentMaybeUndef(const Decl *TargetDecl,
unsigned NumRequiredArgs, unsigned ArgNo) {
const auto *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl);
if (!FD)
return false;
// Assume variadic arguments do not have maybe_undef attribute.
if (ArgNo >= NumRequiredArgs)
return false;
// Check if argument has maybe_undef attribute.
if (ArgNo < FD->getNumParams()) {
const ParmVarDecl *Param = FD->getParamDecl(ArgNo);
if (Param && Param->hasAttr<MaybeUndefAttr>())
return true;
}
return false;
}
/// Test if it's legal to apply nofpclass for the given parameter type and it's
/// lowered IR type.
static bool canApplyNoFPClass(const ABIArgInfo &AI, QualType ParamType,
bool IsReturn) {
// Should only apply to FP types in the source, not ABI promoted.
if (!ParamType->hasFloatingRepresentation())
return false;
// The promoted-to IR type also needs to support nofpclass.
llvm::Type *IRTy = AI.getCoerceToType();
if (llvm::AttributeFuncs::isNoFPClassCompatibleType(IRTy))
return true;
if (llvm::StructType *ST = dyn_cast<llvm::StructType>(IRTy)) {
return !IsReturn && AI.getCanBeFlattened() &&
llvm::all_of(ST->elements(),
llvm::AttributeFuncs::isNoFPClassCompatibleType);
}
return false;
}
void CodeGenModule::AdjustMemoryAttribute(StringRef Name,
CGCalleeInfo CalleeInfo,
llvm::AttributeList &Attrs) {
if (Attrs.getMemoryEffects().getModRef() == llvm::ModRefInfo::NoModRef) {
Attrs = Attrs.removeFnAttribute(getLLVMContext(), llvm::Attribute::Memory);
llvm::Attribute MemoryAttr = llvm::Attribute::getWithMemoryEffects(
getLLVMContext(), llvm::MemoryEffects::writeOnly());
Attrs = Attrs.addFnAttribute(getLLVMContext(), MemoryAttr);
}
}
/// Construct the IR attribute list of a function or call.
///
/// When adding an attribute, please consider where it should be handled:
///
/// - getDefaultFunctionAttributes is for attributes that are essentially
/// part of the global target configuration (but perhaps can be
/// overridden on a per-function basis). Adding attributes there
/// will cause them to also be set in frontends that build on Clang's
/// target-configuration logic, as well as for code defined in library
/// modules such as CUDA's libdevice.
///
/// - ConstructAttributeList builds on top of getDefaultFunctionAttributes
/// and adds declaration-specific, convention-specific, and
/// frontend-specific logic. The last is of particular importance:
/// attributes that restrict how the frontend generates code must be
/// added here rather than getDefaultFunctionAttributes.
///
void CodeGenModule::ConstructAttributeList(StringRef Name,
const CGFunctionInfo &FI,
CGCalleeInfo CalleeInfo,
llvm::AttributeList &AttrList,
unsigned &CallingConv,
bool AttrOnCallSite, bool IsThunk) {
llvm::AttrBuilder FuncAttrs(getLLVMContext());
llvm::AttrBuilder RetAttrs(getLLVMContext());
// Collect function IR attributes from the CC lowering.
// We'll collect the paramete and result attributes later.
CallingConv = FI.getEffectiveCallingConvention();
if (FI.isNoReturn())
FuncAttrs.addAttribute(llvm::Attribute::NoReturn);
if (FI.isCmseNSCall())
FuncAttrs.addAttribute("cmse_nonsecure_call");
// Collect function IR attributes from the callee prototype if we have one.
AddAttributesFromFunctionProtoType(getContext(), FuncAttrs,
CalleeInfo.getCalleeFunctionProtoType());
const Decl *TargetDecl = CalleeInfo.getCalleeDecl().getDecl();
// Attach assumption attributes to the declaration. If this is a call
// site, attach assumptions from the caller to the call as well.
AddAttributesFromOMPAssumes(FuncAttrs, TargetDecl);
bool HasOptnone = false;
// The NoBuiltinAttr attached to the target FunctionDecl.
const NoBuiltinAttr *NBA = nullptr;
// Some ABIs may result in additional accesses to arguments that may
// otherwise not be present.
std::optional<llvm::Attribute::AttrKind> MemAttrForPtrArgs;
bool AddedPotentialArgAccess = false;
auto AddPotentialArgAccess = [&]() {
AddedPotentialArgAccess = true;
llvm::Attribute A = FuncAttrs.getAttribute(llvm::Attribute::Memory);
if (A.isValid())
FuncAttrs.addMemoryAttr(A.getMemoryEffects() |
llvm::MemoryEffects::argMemOnly());
};
// Collect function IR attributes based on declaration-specific
// information.
// 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<HotAttr>())
FuncAttrs.addAttribute(llvm::Attribute::Hot);
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>());
if (AttrOnCallSite && Fn->isReplaceableGlobalAllocationFunction()) {
// A sane operator new returns a non-aliasing pointer.
if (getCodeGenOpts().AssumeSaneOperatorNew &&
Fn->getDeclName().isAnyOperatorNew())
RetAttrs.addAttribute(llvm::Attribute::NoAlias);
}
const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn);
const bool IsVirtualCall = MD && MD->isVirtual();
// Don't use [[noreturn]], _Noreturn or [[no_builtin]] for a call to a
// virtual function. These attributes are not inherited by overloads.
if (!(AttrOnCallSite && IsVirtualCall)) {
if (Fn->isNoReturn())
FuncAttrs.addAttribute(llvm::Attribute::NoReturn);
NBA = Fn->getAttr<NoBuiltinAttr>();
}
}
if (isa<FunctionDecl>(TargetDecl) || isa<VarDecl>(TargetDecl)) {
// Only place nomerge attribute on call sites, never functions. This
// allows it to work on indirect virtual function calls.
if (AttrOnCallSite && TargetDecl->hasAttr<NoMergeAttr>())
FuncAttrs.addAttribute(llvm::Attribute::NoMerge);
}
// 'const', 'pure' and 'noalias' attributed functions are also nounwind.
if (TargetDecl->hasAttr<ConstAttr>()) {
FuncAttrs.addMemoryAttr(llvm::MemoryEffects::none());
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
// gcc specifies that 'const' functions have greater restrictions than
// 'pure' functions, so they also cannot have infinite loops.
FuncAttrs.addAttribute(llvm::Attribute::WillReturn);
MemAttrForPtrArgs = llvm::Attribute::ReadNone;
} else if (TargetDecl->hasAttr<PureAttr>()) {
FuncAttrs.addMemoryAttr(llvm::MemoryEffects::readOnly());
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
// gcc specifies that 'pure' functions cannot have infinite loops.
FuncAttrs.addAttribute(llvm::Attribute::WillReturn);
MemAttrForPtrArgs = llvm::Attribute::ReadOnly;
} else if (TargetDecl->hasAttr<NoAliasAttr>()) {
FuncAttrs.addMemoryAttr(llvm::MemoryEffects::inaccessibleOrArgMemOnly());
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
}
if (const auto *RA = TargetDecl->getAttr<RestrictAttr>();
RA && RA->getDeallocator() == nullptr)
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);
if (TargetDecl->hasAttr<LeafAttr>())
FuncAttrs.addAttribute(llvm::Attribute::NoCallback);
if (TargetDecl->hasAttr<BPFFastCallAttr>())
FuncAttrs.addAttribute("bpf_fastcall");
HasOptnone = TargetDecl->hasAttr<OptimizeNoneAttr>();
if (auto *AllocSize = TargetDecl->getAttr<AllocSizeAttr>()) {
std::optional<unsigned> NumElemsParam;
if (AllocSize->getNumElemsParam().isValid())
NumElemsParam = AllocSize->getNumElemsParam().getLLVMIndex();
FuncAttrs.addAllocSizeAttr(AllocSize->getElemSizeParam().getLLVMIndex(),
NumElemsParam);
}
// 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).
if (getLangOpts().OffloadUniformBlock)
FuncAttrs.addAttribute("uniform-work-group-size");
if (TargetDecl->hasAttr<ArmLocallyStreamingAttr>())
FuncAttrs.addAttribute("aarch64_pstate_sm_body");
if (auto *ModularFormat = TargetDecl->getAttr<ModularFormatAttr>()) {
FormatAttr *Format = TargetDecl->getAttr<FormatAttr>();
StringRef Type = Format->getType()->getName();
std::string FormatIdx = std::to_string(Format->getFormatIdx());
std::string FirstArg = std::to_string(Format->getFirstArg());
SmallVector<StringRef> Args = {
Type, FormatIdx, FirstArg,
ModularFormat->getModularImplFn()->getName(),
ModularFormat->getImplName()};
llvm::append_range(Args, ModularFormat->aspects());
FuncAttrs.addAttribute("modular-format", llvm::join(Args, ","));
}
}
// Attach "no-builtins" attributes to:
// * call sites: both `nobuiltin` and "no-builtins" or "no-builtin-<name>".
// * definitions: "no-builtins" or "no-builtin-<name>" only.
// The attributes can come from:
// * LangOpts: -ffreestanding, -fno-builtin, -fno-builtin-<name>
// * FunctionDecl attributes: __attribute__((no_builtin(...)))
addNoBuiltinAttributes(FuncAttrs, getLangOpts(), NBA);
// Collect function IR attributes based on global settiings.
getDefaultFunctionAttributes(Name, HasOptnone, AttrOnCallSite, FuncAttrs);
// Override some default IR attributes based on declaration-specific
// information.
if (TargetDecl) {
if (TargetDecl->hasAttr<NoSpeculativeLoadHardeningAttr>())
FuncAttrs.removeAttribute(llvm::Attribute::SpeculativeLoadHardening);
if (TargetDecl->hasAttr<SpeculativeLoadHardeningAttr>())
FuncAttrs.addAttribute(llvm::Attribute::SpeculativeLoadHardening);
if (TargetDecl->hasAttr<NoSplitStackAttr>())
FuncAttrs.removeAttribute("split-stack");
if (TargetDecl->hasAttr<ZeroCallUsedRegsAttr>()) {
// A function "__attribute__((...))" overrides the command-line flag.
auto Kind =
TargetDecl->getAttr<ZeroCallUsedRegsAttr>()->getZeroCallUsedRegs();
FuncAttrs.removeAttribute("zero-call-used-regs");
FuncAttrs.addAttribute(
"zero-call-used-regs",
ZeroCallUsedRegsAttr::ConvertZeroCallUsedRegsKindToStr(Kind));
}
// Add NonLazyBind attribute to function declarations when -fno-plt
// is used.
// FIXME: what if we just haven't processed the function definition
// yet, or if it's an external definition like C99 inline?
if (CodeGenOpts.NoPLT) {
if (auto *Fn = dyn_cast<FunctionDecl>(TargetDecl)) {
if (!Fn->isDefined() && !AttrOnCallSite) {
FuncAttrs.addAttribute(llvm::Attribute::NonLazyBind);
}
}
}
// Remove 'convergent' if requested.
if (TargetDecl->hasAttr<NoConvergentAttr>())
FuncAttrs.removeAttribute(llvm::Attribute::Convergent);
}
// Add "sample-profile-suffix-elision-policy" attribute for internal linkage
// functions with -funique-internal-linkage-names.
if (TargetDecl && CodeGenOpts.UniqueInternalLinkageNames) {
if (const auto *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
if (!FD->isExternallyVisible())
FuncAttrs.addAttribute("sample-profile-suffix-elision-policy",
"selected");
}
}
// Collect non-call-site function IR attributes from declaration-specific
// information.
if (!AttrOnCallSite) {
if (TargetDecl && TargetDecl->hasAttr<CmseNSEntryAttr>())
FuncAttrs.addAttribute("cmse_nonsecure_entry");
// Whether tail calls are enabled.
auto shouldDisableTailCalls = [&] {
// Should this be honored in getDefaultFunctionAttributes?
if (CodeGenOpts.DisableTailCalls)
return true;
if (!TargetDecl)
return false;
if (TargetDecl->hasAttr<DisableTailCallsAttr>() ||
TargetDecl->hasAttr<AnyX86InterruptAttr>())
return true;
if (CodeGenOpts.NoEscapingBlockTailCalls) {
if (const auto *BD = dyn_cast<BlockDecl>(TargetDecl))
if (!BD->doesNotEscape())
return true;
}
return false;
};
if (shouldDisableTailCalls())
FuncAttrs.addAttribute("disable-tail-calls", "true");
// These functions require the returns_twice attribute for correct codegen,
// but the attribute may not be added if -fno-builtin is specified. We
// explicitly add that attribute here.
static const llvm::StringSet<> ReturnsTwiceFn{
"_setjmpex", "setjmp", "_setjmp", "vfork",
"sigsetjmp", "__sigsetjmp", "savectx", "getcontext"};
if (ReturnsTwiceFn.contains(Name))
FuncAttrs.addAttribute(llvm::Attribute::ReturnsTwice);
// CPU/feature overrides. addDefaultFunctionDefinitionAttributes
// handles these separately to set them based on the global defaults.
GetCPUAndFeaturesAttributes(CalleeInfo.getCalleeDecl(), FuncAttrs);
// Windows hotpatching support
if (!MSHotPatchFunctions.empty()) {
bool IsHotPatched = llvm::binary_search(MSHotPatchFunctions, Name);
if (IsHotPatched)
FuncAttrs.addAttribute("marked_for_windows_hot_patching");
}
}
// Mark functions that are replaceable by the loader.
if (CodeGenOpts.isLoaderReplaceableFunctionName(Name))
FuncAttrs.addAttribute("loader-replaceable");
// Collect attributes from arguments and return values.
ClangToLLVMArgMapping IRFunctionArgs(getContext(), FI);
QualType RetTy = FI.getReturnType();
const ABIArgInfo &RetAI = FI.getReturnInfo();
const llvm::DataLayout &DL = getDataLayout();
// Determine if the return type could be partially undef
if (CodeGenOpts.EnableNoundefAttrs &&
HasStrictReturn(*this, RetTy, TargetDecl)) {
if (!RetTy->isVoidType() && RetAI.getKind() != ABIArgInfo::Indirect &&
DetermineNoUndef(RetTy, getTypes(), DL, RetAI))
RetAttrs.addAttribute(llvm::Attribute::NoUndef);
}
switch (RetAI.getKind()) {
case ABIArgInfo::Extend:
if (RetAI.isSignExt())
RetAttrs.addAttribute(llvm::Attribute::SExt);
else if (RetAI.isZeroExt())
RetAttrs.addAttribute(llvm::Attribute::ZExt);
else
RetAttrs.addAttribute(llvm::Attribute::NoExt);
[[fallthrough]];
case ABIArgInfo::TargetSpecific:
case ABIArgInfo::Direct:
if (RetAI.getInReg())
RetAttrs.addAttribute(llvm::Attribute::InReg);
if (canApplyNoFPClass(RetAI, RetTy, true))
RetAttrs.addNoFPClassAttr(
CodeGenUtils::getNoFPClassTestMask(getLangOpts()));
break;
case ABIArgInfo::Ignore:
break;
case ABIArgInfo::InAlloca:
case ABIArgInfo::Indirect: {
// inalloca and sret disable readnone and readonly
AddPotentialArgAccess();
break;
}
case ABIArgInfo::CoerceAndExpand:
break;
case ABIArgInfo::Expand:
case ABIArgInfo::IndirectAliased:
llvm_unreachable("Invalid ABI kind for return argument");
}
if (!IsThunk) {
// FIXME: fix this properly, https://reviews.llvm.org/D100388
if (const auto *RefTy = RetTy->getAs<ReferenceType>()) {
QualType PTy = RefTy->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType())
RetAttrs.addDereferenceableAttr(
getMinimumObjectSize(PTy).getQuantity());
if (getTypes().getTargetAddressSpace(PTy) == 0 &&
!CodeGenOpts.NullPointerIsValid)
RetAttrs.addAttribute(llvm::Attribute::NonNull);
if (PTy->isObjectType()) {
llvm::Align Alignment =
getNaturalPointeeTypeAlignment(RetTy).getAsAlign();
RetAttrs.addAlignmentAttr(Alignment);
}
}
}
bool hasUsedSRet = false;
SmallVector<llvm::AttrBuilder, 4> ArgAttrs;
for (unsigned I = 0; I < IRFunctionArgs.totalIRArgs(); ++I)
ArgAttrs.emplace_back(getLLVMContext());
// Attach attributes to sret.
if (IRFunctionArgs.hasSRetArg()) {
llvm::AttrBuilder &SRETAttrs = ArgAttrs[IRFunctionArgs.getSRetArgNo()];
SRETAttrs.addStructRetAttr(getTypes().ConvertTypeForMem(RetTy));
SRETAttrs.addAttribute(llvm::Attribute::Writable);
SRETAttrs.addAttribute(llvm::Attribute::DeadOnUnwind);
hasUsedSRet = true;
if (RetAI.getInReg())
SRETAttrs.addAttribute(llvm::Attribute::InReg);
SRETAttrs.addAlignmentAttr(RetAI.getIndirectAlign().getQuantity());
}
// Attach attributes to inalloca argument.
if (IRFunctionArgs.hasInallocaArg()) {
ArgAttrs[IRFunctionArgs.getInallocaArgNo()].addInAllocaAttr(
FI.getArgStruct());
}
// Apply `nonnull`, `dereferenceable(N)` and `align N` to the `this` argument,
// unless this is a thunk function. Add dead_on_return to the `this` argument
// in base class destructors to aid in DSE.
// FIXME: fix this properly, https://reviews.llvm.org/D100388
if (FI.isInstanceMethod() && !IRFunctionArgs.hasInallocaArg() &&
!FI.arg_begin()->type->isVoidPointerType() && !IsThunk) {
auto IRArgs = IRFunctionArgs.getIRArgs(0);
assert(IRArgs.second == 1 && "Expected only a single `this` pointer.");
llvm::AttrBuilder &Attrs = ArgAttrs[IRArgs.first];
QualType ThisTy = FI.arg_begin()->type.getTypePtr()->getPointeeType();
int64_t ThisSz = getMinimumObjectSize(ThisTy).getQuantity();
if (!CodeGenOpts.NullPointerIsValid &&
getTypes().getTargetAddressSpace(FI.arg_begin()->type) == 0) {
Attrs.addAttribute(llvm::Attribute::NonNull);
Attrs.addDereferenceableAttr(ThisSz);
} else {
// FIXME dereferenceable should be correct here, regardless of
// NullPointerIsValid. However, dereferenceable currently does not always
// respect NullPointerIsValid and may imply nonnull and break the program.
// See https://reviews.llvm.org/D66618 for discussions.
Attrs.addDereferenceableOrNullAttr(ThisSz);
}
llvm::Align Alignment =
getNaturalTypeAlignment(ThisTy, /*BaseInfo=*/nullptr,
/*TBAAInfo=*/nullptr, /*forPointeeType=*/true)
.getAsAlign();
Attrs.addAlignmentAttr(Alignment);
const auto *DD = dyn_cast_if_present<CXXDestructorDecl>(
CalleeInfo.getCalleeDecl().getDecl());
// Do not annotate vector deleting destructors with dead_on_return as the
// this pointer in that case points to an array which we cannot
// statically know the size of. Also do not mark deleting destructors
// dead_on_return as then we might delete stores inside of a user-defined
// operator delete implementation if it gets inlined, which would be
// incorrect as the object's lifetime has already ended and the operator
// delete implementation is allowed to manipulate the underlying storage.
if (DD &&
CalleeInfo.getCalleeDecl().getDtorType() !=
CXXDtorType::Dtor_VectorDeleting &&
CalleeInfo.getCalleeDecl().getDtorType() !=
CXXDtorType::Dtor_Deleting &&
CodeGenOpts.StrictLifetimes) {
const CXXRecordDecl *ClassDecl =
dyn_cast<CXXRecordDecl>(DD->getDeclContext());
// We cannot add dead_on_return if we have virtual base classes because
// they will generally still be live after the base object destructor.
if (ClassDecl->getNumVBases() == 0)
Attrs.addDeadOnReturnAttr(llvm::DeadOnReturnInfo(
Context.getASTRecordLayout(ClassDecl).getDataSize().getQuantity()));
}
}
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(getLLVMContext());
// Add attribute for padding argument, if necessary.
if (IRFunctionArgs.hasPaddingArg(ArgNo)) {
if (AI.getPaddingInReg()) {
ArgAttrs[IRFunctionArgs.getPaddingArgNo(ArgNo)].addAttribute(
llvm::Attribute::InReg);
}
}
// Decide whether the argument we're handling could be partially undef
if (CodeGenOpts.EnableNoundefAttrs &&
DetermineNoUndef(ParamType, getTypes(), DL, AI)) {
Attrs.addAttribute(llvm::Attribute::NoUndef);
}
// '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 if (AI.isZeroExt())
Attrs.addAttribute(llvm::Attribute::ZExt);
else
Attrs.addAttribute(llvm::Attribute::NoExt);
[[fallthrough]];
case ABIArgInfo::TargetSpecific:
case ABIArgInfo::Direct:
if (ArgNo == 0 && FI.isChainCall())
Attrs.addAttribute(llvm::Attribute::Nest);
else if (AI.getInReg())
Attrs.addAttribute(llvm::Attribute::InReg);
Attrs.addStackAlignmentAttr(llvm::MaybeAlign(AI.getDirectAlign()));
if (canApplyNoFPClass(AI, ParamType, false))
Attrs.addNoFPClassAttr(
CodeGenUtils::getNoFPClassTestMask(getLangOpts()));
break;
case ABIArgInfo::Indirect: {
assert(!ParamType->isIncompleteType() &&
"Pass-by-value parameter has incomplete definition?");
if (AI.getInReg())
Attrs.addAttribute(llvm::Attribute::InReg);
// HLSL out and inout parameters must not be marked with ByVal or
// DeadOnReturn attributes because stores to these parameters by the
// callee are visible to the caller.
if (auto ParamABI = FI.getExtParameterInfo(ArgNo).getABI();
ParamABI != ParameterABI::HLSLOut &&
ParamABI != ParameterABI::HLSLInOut) {
// Depending on the ABI, this may be either a byval or a dead_on_return
// argument.
if (AI.getIndirectByVal()) {
Attrs.addByValAttr(getTypes().ConvertTypeForMem(ParamType));
} else {
// Add dead_on_return when the object's lifetime ends in the callee.
// This includes trivially-destructible objects, as well as objects
// whose destruction / clean-up is carried out within the callee
// (e.g., Obj-C ARC-managed structs, MSVC callee-destroyed objects).
if (!ParamType.isDestructedType() || !ParamType->isRecordType() ||
ParamType->castAsRecordDecl()->isParamDestroyedInCallee())
Attrs.addDeadOnReturnAttr(llvm::DeadOnReturnInfo());
}
}
auto *Decl = ParamType->getAsRecordDecl();
if (CodeGenOpts.PassByValueIsNoAlias && Decl &&
Decl->getArgPassingRestrictions() ==
RecordArgPassingKind::CanPassInRegs)
// When calling the function, the pointer passed in will be the only
// reference to the underlying object. Mark it accordingly.
Attrs.addAttribute(llvm::Attribute::NoAlias);
// TODO: We could add the byref attribute if not byval, but it would
// require updating many testcases.
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 an aligned copy is
// already created by the caller, and the align attribute is purely
// informative. However, this can still be useful information for
// optimizations, such as giving us one necessary condition for checking
// if a load to this pointer can be speculatively executed.
assert(!Align.isZero());
Attrs.addAlignmentAttr(Align.getQuantity());
// The `nofree` and `dereferenceable` attributes can already be inferred
// for `byval` arguments. We'll need to provide additional hints
// otherwise.
if (!AI.getIndirectByVal()) {
// Both 6.9.1 of the C standard and [basic.stc.auto] of the C++ standard
// require parameters to have automatic storage duration. Therefore, the
// underlying object of this pointer will not be freed during the
// function's execution.
Attrs.addAttribute(llvm::Attribute::NoFreeObj);
Attrs.addDereferenceableAttr(
Context.getTypeSizeInChars(ParamType).getQuantity());
}
// byval disables readnone and readonly.
AddPotentialArgAccess();
break;
}
case ABIArgInfo::IndirectAliased: {
CharUnits Align = AI.getIndirectAlign();
Attrs.addByRefAttr(getTypes().ConvertTypeForMem(ParamType));
Attrs.addAlignmentAttr(Align.getQuantity());
break;
}
case ABIArgInfo::Ignore:
case ABIArgInfo::Expand:
case ABIArgInfo::CoerceAndExpand:
break;
case ABIArgInfo::InAlloca:
// inalloca disables readnone and readonly.
AddPotentialArgAccess();
continue;
}
if (const auto *RefTy = ParamType->getAs<ReferenceType>()) {
QualType PTy = RefTy->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType())
Attrs.addDereferenceableAttr(getMinimumObjectSize(PTy).getQuantity());
if (getTypes().getTargetAddressSpace(PTy) == 0 &&
!CodeGenOpts.NullPointerIsValid)
Attrs.addAttribute(llvm::Attribute::NonNull);
if (PTy->isObjectType()) {
llvm::Align Alignment =
getNaturalPointeeTypeAlignment(ParamType).getAsAlign();
Attrs.addAlignmentAttr(Alignment);
}
}
// From OpenCL spec v3.0.10 section 6.3.5 Alignment of Types:
// > For arguments to a __kernel function declared to be a pointer to a
// > data type, the OpenCL compiler can assume that the pointee is always
// > appropriately aligned as required by the data type.
if (TargetDecl &&
DeviceKernelAttr::isOpenCLSpelling(
TargetDecl->getAttr<DeviceKernelAttr>()) &&
ParamType->isPointerType()) {
QualType PTy = ParamType->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType()) {
llvm::Align Alignment =
getNaturalPointeeTypeAlignment(ParamType).getAsAlign();
Attrs.addAlignmentAttr(Alignment);
}
}
switch (FI.getExtParameterInfo(ArgNo).getABI()) {
case ParameterABI::HLSLOut:
case ParameterABI::HLSLInOut:
Attrs.addAttribute(llvm::Attribute::NoAlias);
break;
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.addStructRetAttr(getTypes().ConvertTypeForMem(ParamType));
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.Width.getQuantity());
Attrs.addAlignmentAttr(info.Align.getAsAlign());
}
break;
}
case ParameterABI::SwiftErrorResult:
Attrs.addAttribute(llvm::Attribute::SwiftError);
break;
case ParameterABI::SwiftContext:
Attrs.addAttribute(llvm::Attribute::SwiftSelf);
break;
case ParameterABI::SwiftAsyncContext:
Attrs.addAttribute(llvm::Attribute::SwiftAsync);
break;
}
if (FI.getExtParameterInfo(ArgNo).isNoEscape())
Attrs.addCapturesAttr(
llvm::CaptureInfo(llvm::CaptureComponents::Address));
if (Attrs.hasAttributes()) {
unsigned FirstIRArg, NumIRArgs;
std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
for (unsigned i = 0; i < NumIRArgs; i++)
ArgAttrs[FirstIRArg + i].merge(Attrs);
}
}
assert(ArgNo == FI.arg_size());
// We can't see all potential arguments in a varargs declaration; treat them
// as if they can access memory.
if (!AttrOnCallSite && FI.isVariadic())
AddPotentialArgAccess();
ArgNo = 0;
if (AddedPotentialArgAccess && MemAttrForPtrArgs) {
llvm::FunctionType *FunctionType = getTypes().GetFunctionType(FI);
for (CGFunctionInfo::const_arg_iterator I = FI.arg_begin(),
E = FI.arg_end();
I != E; ++I, ++ArgNo) {
if (I->info.isDirect() || I->info.isExpand() ||
I->info.isCoerceAndExpand()) {
unsigned FirstIRArg, NumIRArgs;
std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
for (unsigned i = FirstIRArg; i < FirstIRArg + NumIRArgs; ++i) {
// The index may be out-of-bounds if the callee is a varargs
// function.
//
// FIXME: We can compute the types of varargs arguments without going
// through the function type, but the relevant code isn't exposed
// in a way that can be called from here.
if (i < FunctionType->getNumParams() &&
FunctionType->getParamType(i)->isPointerTy()) {
ArgAttrs[i].addAttribute(*MemAttrForPtrArgs);
}
}
}
}
}
SmallVector<llvm::AttributeSet, 4> ArgAttrSets;
for (const llvm::AttrBuilder &Attrs : ArgAttrs)
ArgAttrSets.push_back(llvm::AttributeSet::get(getLLVMContext(), Attrs));
AttrList = llvm::AttributeList::get(
getLLVMContext(), llvm::AttributeSet::get(getLLVMContext(), FuncAttrs),
llvm::AttributeSet::get(getLLVMContext(), RetAttrs), ArgAttrSets);
}
/// 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);
}
};
} // namespace
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);
assert(Fn->arg_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(Fn->getArg(IRFunctionArgs.getInallocaArgNo()),
FI.getArgStruct(), FI.getArgStructAlignment());
// Name the struct return parameter.
if (IRFunctionArgs.hasSRetArg()) {
auto AI = Fn->getArg(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());
if (ArgI.getInAllocaIndirect())
V = Address(Builder.CreateLoad(V), ConvertTypeForMem(Ty),
getContext().getTypeAlignInChars(Ty));
ArgVals.push_back(ParamValue::forIndirect(V));
break;
}
case ABIArgInfo::Indirect:
case ABIArgInfo::IndirectAliased: {
assert(NumIRArgs == 1);
Address ParamAddr = makeNaturalAddressForPointer(
Fn->getArg(FirstIRArg), Ty, ArgI.getIndirectAlign(), false, nullptr,
nullptr, KnownNonNull);
if (!hasScalarEvaluationKind(Ty)) {
// Aggregates and complex variables are accessed by reference. All we
// need to do is realign the value, if requested. Also, if the address
// may be aliased, copy it to ensure that the parameter variable is
// mutable and has a unique adress, as C requires.
if (ArgI.getIndirectRealign() || ArgI.isIndirectAliased()) {
RawAddress AlignedTemp = CreateMemTempWithoutCast(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);
Builder.CreateMemCpy(
AlignedTemp.getPointer(), AlignedTemp.getAlignment().getAsAlign(),
ParamAddr.emitRawPointer(*this),
ParamAddr.getAlignment().getAsAlign(),
llvm::ConstantInt::get(IntPtrTy, Size.getQuantity()));
ParamAddr = AlignedTemp;
}
ArgVals.push_back(ParamValue::forIndirect(ParamAddr));
} 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: {
auto AI = Fn->getArg(FirstIRArg);
llvm::Type *LTy = ConvertType(Arg->getType());
// Prepare parameter attributes. So far, only attributes for pointer
// parameters are prepared. See
// http://llvm.org/docs/LangRef.html#paramattrs.
if (ArgI.getDirectOffset() == 0 && LTy->isPointerTy() &&
ArgI.getCoerceToType()->isPointerTy()) {
assert(NumIRArgs == 1);
if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(Arg)) {
// Set `nonnull` attribute if any.
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() == ArraySizeModifier::Static) {
QualType ETy = ArrTy->getElementType();
llvm::Align Alignment =
CGM.getNaturalTypeAlignment(ETy).getAsAlign();
AI->addAttrs(llvm::AttrBuilder(getLLVMContext())
.addAlignmentAttr(Alignment));
uint64_t ArrSize = ArrTy->getZExtSize();
if (!ETy->isIncompleteType() && ETy->isConstantSizeType() &&
ArrSize) {
llvm::AttrBuilder Attrs(getLLVMContext());
Attrs.addDereferenceableAttr(
getContext().getTypeSizeInChars(ETy).getQuantity() *
ArrSize);
AI->addAttrs(Attrs);
} else if (getContext().getTargetInfo().getNullPointerValue(
ETy.getAddressSpace()) == 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() == ArraySizeModifier::Static) {
QualType ETy = ArrTy->getElementType();
llvm::Align Alignment =
CGM.getNaturalTypeAlignment(ETy).getAsAlign();
AI->addAttrs(llvm::AttrBuilder(getLLVMContext())
.addAlignmentAttr(Alignment));
if (!getTypes().getTargetAddressSpace(ETy) &&
!CGM.getCodeGenOpts().NullPointerIsValid)
AI->addAttr(llvm::Attribute::NonNull);
}
}
// Set `align` attribute if any.
const auto *AVAttr = PVD->getAttr<AlignValueAttr>();
if (!AVAttr)
if (const auto *TOTy = OTy->getAs<TypedefType>())
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::ConstantInt *AlignmentCI =
cast<llvm::ConstantInt>(EmitScalarExpr(AVAttr->getAlignment()));
uint64_t AlignmentInt =
AlignmentCI->getLimitedValue(llvm::Value::MaximumAlignment);
if (AI->getParamAlign().valueOrOne() < AlignmentInt) {
AI->removeAttr(llvm::Attribute::AttrKind::Alignment);
AI->addAttrs(llvm::AttrBuilder(getLLVMContext())
.addAlignmentAttr(llvm::Align(AlignmentInt)));
}
}
}
// Set 'noalias' if an argument type has the `restrict` qualifier.
if (Arg->getType().isRestrictQualified())
AI->addAttr(llvm::Attribute::NoAlias);
}
// Prepare the argument value. 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 expects swifterror parameters to be used in very restricted
// ways. Copy the value into a less-restricted temporary.
llvm::Value *V = AI;
if (FI.getExtParameterInfo(ArgNo).getABI() ==
ParameterABI::SwiftErrorResult) {
QualType pointeeTy = Ty->getPointeeType();
assert(pointeeTy->isPointerType());
RawAddress temp = CreateMemTempWithoutCast(
pointeeTy, getPointerAlign(), "swifterror.temp");
Address arg = makeNaturalAddressForPointer(
V, pointeeTy, 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;
}
// VLST arguments are coerced to VLATs at the function boundary for
// ABI consistency. If this is a VLST that was coerced to
// a VLAT at the function boundary and the types match up, use
// llvm.vector.extract to convert back to the original VLST.
if (auto *VecTyTo = dyn_cast<llvm::FixedVectorType>(ConvertType(Ty))) {
llvm::Value *ArgVal = Fn->getArg(FirstIRArg);
if (auto *VecTyFrom =
dyn_cast<llvm::ScalableVectorType>(ArgVal->getType())) {
auto [Coerced, Extracted] = CoerceScalableToFixed(
*this, VecTyTo, VecTyFrom, ArgVal, Arg->getName());
if (Extracted) {
assert(NumIRArgs == 1);
ArgVals.push_back(ParamValue::forDirect(Coerced));
break;
}
}
}
llvm::StructType *STy =
dyn_cast<llvm::StructType>(ArgI.getCoerceToType());
Address Alloca = CreateMemTempWithoutCast(
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.
if (ArgI.isDirect() && ArgI.getCanBeFlattened() && STy &&
STy->getNumElements() > 1) {
llvm::TypeSize StructSize = CGM.getDataLayout().getTypeAllocSize(STy);
llvm::TypeSize PtrElementSize =
CGM.getDataLayout().getTypeAllocSize(Ptr.getElementType());
if (StructSize.isScalable()) {
assert(STy->containsHomogeneousScalableVectorTypes() &&
"ABI only supports structure with homogeneous scalable vector "
"type");
assert(StructSize == PtrElementSize &&
"Only allow non-fractional movement of structure with"
"homogeneous scalable vector type");
assert(STy->getNumElements() == NumIRArgs);
llvm::Value *LoadedStructValue = llvm::PoisonValue::get(STy);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
auto *AI = Fn->getArg(FirstIRArg + i);
AI->setName(Arg->getName() + ".coerce" + Twine(i));
LoadedStructValue =
Builder.CreateInsertValue(LoadedStructValue, AI, i);
}
Builder.CreateStore(LoadedStructValue, Ptr);
} else {
uint64_t SrcSize = StructSize.getFixedValue();
uint64_t DstSize = PtrElementSize.getFixedValue();
Address AddrToStoreInto = Address::invalid();
if (SrcSize <= DstSize) {
AddrToStoreInto = Ptr.withElementType(STy);
} else {
AddrToStoreInto =
CreateTempAlloca(STy, Alloca.getAlignment(), "coerce");
}
assert(STy->getNumElements() == NumIRArgs);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
auto AI = Fn->getArg(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);
}
// Structures with PFP fields require a coerced store to add any
// pointer signatures.
if (getContext().hasPFPFields(Ty)) {
llvm::Value *Struct = Builder.CreateLoad(Ptr);
CreatePFPCoercedStore(Struct, Ty, Ptr, *this);
}
}
} else {
// Simple case, just do a coerced store of the argument into the alloca.
assert(NumIRArgs == 1);
auto AI = Fn->getArg(FirstIRArg);
AI->setName(Arg->getName() + ".coerce");
CreateCoercedStore(
AI, Ty, Ptr,
llvm::TypeSize::getFixed(
getContext().getTypeSizeInChars(Ty).getQuantity() -
ArgI.getDirectOffset()),
/*DstIsVolatile=*/false);
}
// 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 =
CreateMemTempWithoutCast(Ty, getContext().getDeclAlign(Arg));
ArgVals.push_back(ParamValue::forIndirect(alloca));
auto coercionType = ArgI.getCoerceAndExpandType();
auto unpaddedCoercionType = ArgI.getUnpaddedCoerceAndExpandType();
auto *unpaddedStruct = dyn_cast<llvm::StructType>(unpaddedCoercionType);
alloca = alloca.withElementType(coercionType);
unsigned argIndex = FirstIRArg;
unsigned unpaddedIndex = 0;
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);
llvm::Value *elt = Fn->getArg(argIndex++);
auto paramType = unpaddedStruct
? unpaddedStruct->getElementType(unpaddedIndex++)
: unpaddedCoercionType;
if (auto *VecTyTo = dyn_cast<llvm::FixedVectorType>(eltType)) {
if (auto *VecTyFrom = dyn_cast<llvm::ScalableVectorType>(paramType)) {
bool Extracted;
std::tie(elt, Extracted) = CoerceScalableToFixed(
*this, VecTyTo, VecTyFrom, elt, elt->getName());
assert(Extracted && "Unexpected scalable to fixed vector coercion");
}
}
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 =
CreateMemTempWithoutCast(Ty, getContext().getDeclAlign(Arg));
LValue LV = MakeAddrLValue(Alloca, Ty);
ArgVals.push_back(ParamValue::forIndirect(Alloca));
auto FnArgIter = Fn->arg_begin() + FirstIRArg;
ExpandTypeFromArgs(Ty, LV, FnArgIter);
assert(FnArgIter == Fn->arg_begin() + FirstIRArg + NumIRArgs);
for (unsigned i = 0, e = NumIRArgs; i != e; ++i) {
auto AI = Fn->getArg(FirstIRArg + i);
AI->setName(Arg->getName() + "." + Twine(i));
}
break;
}
case ABIArgInfo::TargetSpecific: {
auto *AI = Fn->getArg(FirstIRArg);
AI->setName(Arg->getName() + ".target_coerce");
Address Alloca = CreateMemTempWithoutCast(
Ty, getContext().getDeclAlign(Arg), Arg->getName());
Address Ptr = emitAddressAtOffset(*this, Alloca, ArgI);
CGM.getABIInfo().createCoercedStore(AI, Ptr, ArgI, false, *this);
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::Ignore:
assert(NumIRArgs == 0);
// Initialize the local variable appropriately.
if (!hasScalarEvaluationKind(Ty)) {
ArgVals.push_back(
ParamValue::forIndirect(CreateMemTempWithoutCast(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->getCalledOperand() == CGF.CGM.getObjCEntrypoints().objc_retain) {
doRetainAutorelease = true;
} else if (call->getCalledOperand() ==
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)->getCalledOperand() ==
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. Note: stripPointerCasts looks through returned arg
// functions, which would cause us to miss the retain.
llvm::CallInst *retainCall = dyn_cast<llvm::CallInst>(result);
if (!retainCall || retainCall->getCalledOperand() !=
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).getBasePointer())
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) {
llvm::Value *ReturnValuePtr = CGF.ReturnValue.getBasePointer();
// 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,
ReturnValuePtr](llvm::User *U) -> llvm::StoreInst * {
auto *SI = dyn_cast<llvm::StoreInst>(U);
if (!SI || SI->getPointerOperand() != ReturnValuePtr ||
SI->getValueOperand()->getType() != CGF.ReturnValue.getElementType())
return nullptr;
// These aren't actually possible for non-coerced returns, and we
// only care about non-coerced returns on this code path.
// All memory instructions inside __try block are volatile.
assert(!SI->isAtomic() &&
(!SI->isVolatile() || CGF.currentFunctionUsesSEHTry()));
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 (!ReturnValuePtr->hasOneUse()) {
llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
if (IP->empty())
return nullptr;
// Look at directly preceding instruction, skipping bitcasts, lifetime
// markers, and fake uses and their operands.
const llvm::Instruction *LoadIntoFakeUse = nullptr;
for (llvm::Instruction &I : llvm::reverse(*IP)) {
// Ignore instructions that are just loads for fake uses; the load should
// immediately precede the fake use, so we only need to remember the
// operand for the last fake use seen.
if (LoadIntoFakeUse == &I)
continue;
if (isa<llvm::BitCastInst>(&I))
continue;
if (auto *II = dyn_cast<llvm::IntrinsicInst>(&I)) {
if (II->getIntrinsicID() == llvm::Intrinsic::lifetime_end)
continue;
if (II->getIntrinsicID() == llvm::Intrinsic::fake_use) {
LoadIntoFakeUse = dyn_cast<llvm::Instruction>(II->getArgOperand(0));
continue;
}
}
return GetStoreIfValid(&I);
}
return nullptr;
}
llvm::StoreInst *store = GetStoreIfValid(ReturnValuePtr->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();
llvm::SmallPtrSet<llvm::BasicBlock *, 4> SeenBBs;
while (IP != StoreBB) {
if (!SeenBBs.insert(IP).second || !(IP = IP->getSinglePredecessor()))
return nullptr;
}
// Okay, the store's basic block dominates the insertion point; we
// can do our thing.
return store;
}
// Helper functions for EmitCMSEClearRecord
// Set the bits corresponding to a field having width `BitWidth` and located at
// offset `BitOffset` (from the least significant bit) within a storage unit of
// `Bits.size()` bytes. Each element of `Bits` corresponds to one target byte.
// Use little-endian layout, i.e.`Bits[0]` is the LSB.
static void setBitRange(SmallVectorImpl<uint64_t> &Bits, int BitOffset,
int BitWidth, int CharWidth) {
assert(CharWidth <= 64);
assert(static_cast<unsigned>(BitWidth) <= Bits.size() * CharWidth);
int Pos = 0;
if (BitOffset >= CharWidth) {
Pos += BitOffset / CharWidth;
BitOffset = BitOffset % CharWidth;
}
const uint64_t Used = (uint64_t(1) << CharWidth) - 1;
if (BitOffset + BitWidth >= CharWidth) {
Bits[Pos++] |= (Used << BitOffset) & Used;
BitWidth -= CharWidth - BitOffset;
BitOffset = 0;
}
while (BitWidth >= CharWidth) {
Bits[Pos++] = Used;
BitWidth -= CharWidth;
}
if (BitWidth > 0)
Bits[Pos++] |= (Used >> (CharWidth - BitWidth)) << BitOffset;
}
// Set the bits corresponding to a field having width `BitWidth` and located at
// offset `BitOffset` (from the least significant bit) within a storage unit of
// `StorageSize` bytes, located at `StorageOffset` in `Bits`. Each element of
// `Bits` corresponds to one target byte. Use target endian layout.
static void setBitRange(SmallVectorImpl<uint64_t> &Bits, int StorageOffset,
int StorageSize, int BitOffset, int BitWidth,
int CharWidth, bool BigEndian) {
SmallVector<uint64_t, 8> TmpBits(StorageSize);
setBitRange(TmpBits, BitOffset, BitWidth, CharWidth);
if (BigEndian)
std::reverse(TmpBits.begin(), TmpBits.end());
for (uint64_t V : TmpBits)
Bits[StorageOffset++] |= V;
}
static void setUsedBits(CodeGenModule &, QualType, int,
SmallVectorImpl<uint64_t> &);
// Set the bits in `Bits`, which correspond to the value representations of
// the actual members of the record type `RTy`. Note that this function does
// not handle base classes, virtual tables, etc, since they cannot happen in
// CMSE function arguments or return. The bit mask corresponds to the target
// memory layout, i.e. it's endian dependent.
static void setUsedBits(CodeGenModule &CGM, const RecordType *RTy, int Offset,
SmallVectorImpl<uint64_t> &Bits) {
ASTContext &Context = CGM.getContext();
int CharWidth = Context.getCharWidth();
const RecordDecl *RD = RTy->getDecl()->getDefinition();
const ASTRecordLayout &ASTLayout = Context.getASTRecordLayout(RD);
const CGRecordLayout &Layout = CGM.getTypes().getCGRecordLayout(RD);
int Idx = 0;
for (auto I = RD->field_begin(), E = RD->field_end(); I != E; ++I, ++Idx) {
const FieldDecl *F = *I;
if (F->isUnnamedBitField() || F->isZeroLengthBitField() ||
F->getType()->isIncompleteArrayType())
continue;
if (F->isBitField()) {
const CGBitFieldInfo &BFI = Layout.getBitFieldInfo(F);
setBitRange(Bits, Offset + BFI.StorageOffset.getQuantity(),
BFI.StorageSize / CharWidth, BFI.Offset, BFI.Size, CharWidth,
CGM.getDataLayout().isBigEndian());
continue;
}
setUsedBits(CGM, F->getType(),
Offset + ASTLayout.getFieldOffset(Idx) / CharWidth, Bits);
}
}
// Set the bits in `Bits`, which correspond to the value representations of
// the elements of an array type `ATy`.
static void setUsedBits(CodeGenModule &CGM, const ConstantArrayType *ATy,
int Offset, SmallVectorImpl<uint64_t> &Bits) {
const ASTContext &Context = CGM.getContext();
QualType ETy = Context.getBaseElementType(ATy);
int Size = Context.getTypeSizeInChars(ETy).getQuantity();
SmallVector<uint64_t, 4> TmpBits(Size);
setUsedBits(CGM, ETy, 0, TmpBits);
for (int I = 0, N = Context.getConstantArrayElementCount(ATy); I < N; ++I) {
auto Src = TmpBits.begin();
auto Dst = Bits.begin() + Offset + I * Size;
for (int J = 0; J < Size; ++J)
*Dst++ |= *Src++;
}
}
// Set the bits in `Bits`, which correspond to the value representations of
// the type `QTy`.
static void setUsedBits(CodeGenModule &CGM, QualType QTy, int Offset,
SmallVectorImpl<uint64_t> &Bits) {
if (const auto *RTy = QTy->getAsCanonical<RecordType>())
return setUsedBits(CGM, RTy, Offset, Bits);
ASTContext &Context = CGM.getContext();
if (const auto *ATy = Context.getAsConstantArrayType(QTy))
return setUsedBits(CGM, ATy, Offset, Bits);
int Size = Context.getTypeSizeInChars(QTy).getQuantity();
if (Size <= 0)
return;
std::fill_n(Bits.begin() + Offset, Size,
(uint64_t(1) << Context.getCharWidth()) - 1);
}
static uint64_t buildMultiCharMask(const SmallVectorImpl<uint64_t> &Bits,
int Pos, int Size, int CharWidth,
bool BigEndian) {
assert(Size > 0);
uint64_t Mask = 0;
if (BigEndian) {
for (auto P = Bits.begin() + Pos, E = Bits.begin() + Pos + Size; P != E;
++P)
Mask = (Mask << CharWidth) | *P;
} else {
auto P = Bits.begin() + Pos + Size, End = Bits.begin() + Pos;
do
Mask = (Mask << CharWidth) | *--P;
while (P != End);
}
return Mask;
}
// Emit code to clear the bits in a record, which aren't a part of any user
// declared member, when the record is a function return.
llvm::Value *CodeGenFunction::EmitCMSEClearRecord(llvm::Value *Src,
llvm::IntegerType *ITy,
QualType QTy) {
assert(Src->getType() == ITy);
assert(ITy->getScalarSizeInBits() <= 64);
const llvm::DataLayout &DataLayout = CGM.getDataLayout();
int Size = DataLayout.getTypeStoreSize(ITy);
SmallVector<uint64_t, 4> Bits(Size);
setUsedBits(CGM, QTy->castAsCanonical<RecordType>(), 0, Bits);
int CharWidth = CGM.getContext().getCharWidth();
uint64_t Mask =
buildMultiCharMask(Bits, 0, Size, CharWidth, DataLayout.isBigEndian());
return Builder.CreateAnd(Src, Mask, "cmse.clear");
}
// Emit code to clear the bits in a record, which aren't a part of any user
// declared member, when the record is a function argument.
llvm::Value *CodeGenFunction::EmitCMSEClearRecord(llvm::Value *Src,
llvm::ArrayType *ATy,
QualType QTy) {
const llvm::DataLayout &DataLayout = CGM.getDataLayout();
int Size = DataLayout.getTypeStoreSize(ATy);
SmallVector<uint64_t, 16> Bits(Size);
setUsedBits(CGM, QTy->castAsCanonical<RecordType>(), 0, Bits);
// Clear each element of the LLVM array.
int CharWidth = CGM.getContext().getCharWidth();
int CharsPerElt =
ATy->getArrayElementType()->getScalarSizeInBits() / CharWidth;
int MaskIndex = 0;
llvm::Value *R = llvm::PoisonValue::get(ATy);
for (int I = 0, N = ATy->getArrayNumElements(); I != N; ++I) {
uint64_t Mask = buildMultiCharMask(Bits, MaskIndex, CharsPerElt, CharWidth,
DataLayout.isBigEndian());
MaskIndex += CharsPerElt;
llvm::Value *T0 = Builder.CreateExtractValue(Src, I);
llvm::Value *T1 = Builder.CreateAnd(T0, Mask, "cmse.clear");
R = Builder.CreateInsertValue(R, T1, I);
}
return R;
}
void CodeGenFunction::EmitFunctionEpilog(
const CGFunctionInfo &FI, bool EmitRetDbgLoc, SourceLocation EndLoc,
uint64_t RetKeyInstructionsSourceAtom) {
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()) {
auto *I = Builder.CreateRetVoid();
if (RetKeyInstructionsSourceAtom)
addInstToSpecificSourceAtom(I, nullptr, RetKeyInstructionsSourceAtom);
else
addInstToNewSourceAtom(I, nullptr);
return;
}
llvm::DebugLoc RetDbgLoc;
llvm::Value *RV = nullptr;
QualType RetTy = FI.getReturnType();
const ABIArgInfo &RetAI = FI.getReturnInfo();
switch (RetAI.getKind()) {
case ABIArgInfo::InAlloca:
// Aggregates 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(
FI.getArgStruct(), ArgStruct, RetAI.getInAllocaFieldIndex());
llvm::Type *Ty =
cast<llvm::GetElementPtrInst>(SRet)->getResultElementType();
RV = Builder.CreateAlignedLoad(Ty, 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; aggregates get evaluated directly into the destination.
break;
case TEK_Scalar: {
LValueBaseInfo BaseInfo;
TBAAAccessInfo TBAAInfo;
CharUnits Alignment =
CGM.getNaturalTypeAlignment(RetTy, &BaseInfo, &TBAAInfo);
Address ArgAddr(&*AI, ConvertType(RetTy), Alignment);
LValue ArgVal =
LValue::MakeAddr(ArgAddr, RetTy, getContext(), BaseInfo, TBAAInfo);
EmitStoreOfScalar(
EmitLoadOfScalar(MakeAddrLValue(ReturnValue, RetTy), EndLoc), ArgVal,
/*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, RetTy, 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();
auto unpaddedCoercionType = RetAI.getUnpaddedCoerceAndExpandType();
auto *unpaddedStruct = dyn_cast<llvm::StructType>(unpaddedCoercionType);
// Load all of the coerced elements out into results.
llvm::SmallVector<llvm::Value *, 4> results;
Address addr = ReturnValue.withElementType(coercionType);
unsigned unpaddedIndex = 0;
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);
llvm::Value *elt = CreateCoercedLoad(
eltAddr, RetTy,
unpaddedStruct ? unpaddedStruct->getElementType(unpaddedIndex++)
: unpaddedCoercionType,
*this);
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::PoisonValue::get(returnType);
for (unsigned i = 0, e = results.size(); i != e; ++i) {
RV = Builder.CreateInsertValue(RV, results[i], i);
}
}
break;
}
case ABIArgInfo::TargetSpecific: {
Address V = emitAddressAtOffset(*this, ReturnValue, RetAI);
RV = CGM.getABIInfo().createCoercedLoad(V, RetAI, *this);
break;
}
case ABIArgInfo::Expand:
case ABIArgInfo::IndirectAliased:
llvm_unreachable("Invalid ABI kind for return argument");
}
llvm::Instruction *Ret;
if (RV) {
if (CurFuncDecl && CurFuncDecl->hasAttr<CmseNSEntryAttr>()) {
// For certain return types, clear padding bits, as they may reveal
// sensitive information.
// Small struct/union types are passed as integers.
auto *ITy = dyn_cast<llvm::IntegerType>(RV->getType());
if (ITy != nullptr && isa<RecordType>(RetTy.getCanonicalType()))
RV = EmitCMSEClearRecord(RV, ITy, RetTy);
}
EmitReturnValueCheck(RV);
Ret = Builder.CreateRet(RV);
} else {
Ret = Builder.CreateRetVoid();
}
if (RetDbgLoc)
Ret->setDebugLoc(std::move(RetDbgLoc));
llvm::Value *Backup = RV ? Ret->getOperand(0) : nullptr;
if (RetKeyInstructionsSourceAtom)
addInstToSpecificSourceAtom(Ret, Backup, RetKeyInstructionsSourceAtom);
else
addInstToNewSourceAtom(Ret, Backup);
}
void CodeGenFunction::EmitReturnValueCheck(llvm::Value *RV) {
// A current decl may not be available when emitting vtable thunks.
if (!CurCodeDecl)
return;
// If the return block isn't reachable, neither is this check, so don't emit
// it.
if (ReturnBlock.isValid() && ReturnBlock.getBlock()->use_empty())
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;
SanitizerKind::SanitizerOrdinal CheckKind;
SanitizerHandler Handler;
if (RetNNAttr) {
assert(!requiresReturnValueNullabilityCheck() &&
"Cannot check nullability and the nonnull attribute");
AttrLoc = RetNNAttr->getLocation();
CheckKind = SanitizerKind::SO_ReturnsNonnullAttribute;
Handler = SanitizerHandler::NonnullReturn;
} else {
if (auto *DD = dyn_cast<DeclaratorDecl>(CurCodeDecl))
if (auto *TSI = DD->getTypeSourceInfo())
if (auto FTL = TSI->getTypeLoc().getAsAdjusted<FunctionTypeLoc>())
AttrLoc = FTL.getReturnLoc().findNullabilityLoc();
CheckKind = SanitizerKind::SO_NullabilityReturn;
Handler = SanitizerHandler::NullabilityReturn;
}
SanitizerDebugLocation SanScope(this, {CheckKind}, Handler);
// 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 = llvm::PointerType::getUnqual(CGF.getLLVMContext());
llvm::Value *Placeholder = llvm::PoisonValue::get(IRPtrTy);
// 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, IRTy, 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();
// 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 (type->isRecordType() && !CurFuncIsThunk &&
type->castAsRecordDecl()->isParamDestroyedInCallee() &&
param->needsDestruction(getContext())) {
EHScopeStack::stable_iterator cleanup =
CalleeDestructedParamCleanups.lookup(cast<ParmVarDecl>(param));
assert(cleanup.isValid() &&
"cleanup for callee-destructed param not recorded");
// This load is a temporary marker which will be removed later.
llvm::Instruction *isActive =
Builder.CreateFlagLoad(llvm::Constant::getNullValue(Int8PtrTy));
args.addArgCleanupDeactivation(cleanup, isActive);
}
}
static bool isProvablyNull(llvm::Value *addr) {
return llvm::isa_and_nonnull<llvm::ConstantPointerNull>(addr);
}
static bool isProvablyNonNull(Address Addr, CodeGenFunction &CGF) {
return llvm::isKnownNonZero(Addr.getBasePointer(), CGF.CGM.getDataLayout());
}
/// 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.getBasePointer()) &&
"shouldn't have writeback for provably null argument");
if (writeback.WritebackExpr) {
CGF.EmitIgnoredExpr(writeback.WritebackExpr);
CGF.EmitLifetimeEnd(writeback.Temporary.getBasePointer());
return;
}
llvm::BasicBlock *contBB = nullptr;
// If the argument wasn't provably non-null, we need to null check
// before doing the store.
bool provablyNonNull = isProvablyNonNull(srcAddr, CGF);
if (!provablyNonNull) {
llvm::BasicBlock *writebackBB = CGF.createBasicBlock("icr.writeback");
contBB = CGF.createBasicBlock("icr.done");
llvm::Value *isNull = CGF.Builder.CreateIsNull(srcAddr, "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 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()));
llvm::Type *destElemType =
CGF.ConvertTypeForMem(CRE->getType()->getPointeeType());
// If the address is a constant null, just pass the appropriate null.
if (isProvablyNull(srcAddr.getBasePointer())) {
args.add(RValue::get(llvm::ConstantPointerNull::get(destType)),
CRE->getType());
return;
}
// Create the temporary.
Address temp =
CGF.CreateTempAlloca(destElemType, 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>(destElemType));
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 = isProvablyNonNull(srcAddr, CGF);
if (provablyNonNull) {
finalArgument = temp.emitRawPointer(CGF);
} else {
llvm::Value *isNull = CGF.Builder.CreateIsNull(srcAddr, "icr.isnull");
finalArgument = CGF.Builder.CreateSelect(
isNull, llvm::ConstantPointerNull::get(destType),
temp.emitRawPointer(CGF), "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, destElemType, "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::PoisonValue::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.
StackBase = CGF.Builder.CreateStackSave("inalloca.save");
}
void CallArgList::freeArgumentMemory(CodeGenFunction &CGF) const {
if (StackBase) {
// Restore the stack after the call.
CGF.Builder.CreateStackRestore(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 &&
!PVD->getType()->isRecordType()) {
auto Nullability = PVD->getType()->getNullability();
CanCheckNullability = Nullability &&
*Nullability == NullabilityKind::NonNull &&
PVD->getTypeSourceInfo();
}
if (!NNAttr && !CanCheckNullability)
return;
SourceLocation AttrLoc;
SanitizerKind::SanitizerOrdinal CheckKind;
SanitizerHandler Handler;
if (NNAttr) {
AttrLoc = NNAttr->getLocation();
CheckKind = SanitizerKind::SO_NonnullAttribute;
Handler = SanitizerHandler::NonnullArg;
} else {
AttrLoc = PVD->getTypeSourceInfo()->getTypeLoc().findNullabilityLoc();
CheckKind = SanitizerKind::SO_NullabilityArg;
Handler = SanitizerHandler::NullabilityArg;
}
SanitizerDebugLocation SanScope(this, {CheckKind}, Handler);
llvm::Value *Cond = EmitNonNullRValueCheck(RV, ArgType);
llvm::Constant *StaticData[] = {
EmitCheckSourceLocation(ArgLoc),
EmitCheckSourceLocation(AttrLoc),
llvm::ConstantInt::get(Int32Ty, ArgNo + 1),
};
EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, {});
}
void CodeGenFunction::EmitNonNullArgCheck(Address Addr, QualType ArgType,
SourceLocation ArgLoc,
AbstractCallee AC, unsigned ParmNum) {
if (!AC.getDecl() || !(SanOpts.has(SanitizerKind::NonnullAttribute) ||
SanOpts.has(SanitizerKind::NullabilityArg)))
return;
EmitNonNullArgCheck(RValue::get(Addr, *this), ArgType, ArgLoc, AC, ParmNum);
}
// Check if the call is going to use the inalloca convention. This needs to
// agree with CGFunctionInfo::usesInAlloca. The CGFunctionInfo is arranged
// later, so we can't check it directly.
static bool hasInAllocaArgs(CodeGenModule &CGM, CallingConv ExplicitCC,
ArrayRef<QualType> ArgTypes) {
// The Swift calling conventions don't go through the target-specific
// argument classification, they never use inalloca.
// TODO: Consider limiting inalloca use to only calling conventions supported
// by MSVC.
if (ExplicitCC == CC_Swift || ExplicitCC == CC_SwiftAsync)
return false;
if (!CGM.getTarget().getCXXABI().isMicrosoft())
return false;
return llvm::any_of(ArgTypes, [&](QualType Ty) {
return isInAllocaArgument(CGM.getCXXABI(), Ty);
});
}
#ifndef NDEBUG
// Determine whether the given argument is an Objective-C method
// that may have type parameters in its signature.
static bool isObjCMethodWithTypeParams(const ObjCMethodDecl *method) {
const DeclContext *dc = method->getDeclContext();
if (const ObjCInterfaceDecl *classDecl = dyn_cast<ObjCInterfaceDecl>(dc)) {
return classDecl->getTypeParamListAsWritten();
}
if (const ObjCCategoryDecl *catDecl = dyn_cast<ObjCCategoryDecl>(dc)) {
return catDecl->getTypeParamList();
}
return false;
}
#endif
/// EmitCallArgs - Emit call arguments for a function.
void CodeGenFunction::EmitCallArgs(
CallArgList &Args, PrototypeWrapper Prototype,
llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
AbstractCallee AC, unsigned ParamsToSkip, EvaluationOrder Order) {
SmallVector<QualType, 16> ArgTypes;
assert((ParamsToSkip == 0 || Prototype.P) &&
"Can't skip parameters if type info is not provided");
// This variable only captures *explicitly* written conventions, not those
// applied by default via command line flags or target defaults, such as
// thiscall, aapcs, stdcall via -mrtd, etc. Computing that correctly would
// require knowing if this is a C++ instance method or being able to see
// unprototyped FunctionTypes.
CallingConv ExplicitCC = CC_C;
// First, if a prototype was provided, use those argument types.
bool IsVariadic = false;
if (Prototype.P) {
const auto *MD = dyn_cast<const ObjCMethodDecl *>(Prototype.P);
if (MD) {
IsVariadic = MD->isVariadic();
ExplicitCC = getCallingConventionForDecl(
MD, CGM.getTarget().getTriple().isOSWindows());
ArgTypes.assign(MD->param_type_begin() + ParamsToSkip,
MD->param_type_end());
} else {
const auto *FPT = cast<const FunctionProtoType *>(Prototype.P);
IsVariadic = FPT->isVariadic();
ExplicitCC = FPT->getExtInfo().getCC();
ArgTypes.assign(FPT->param_type_begin() + ParamsToSkip,
FPT->param_type_end());
}
#ifndef NDEBUG
// Check that the prototyped types match the argument expression types.
bool isGenericMethod = MD && isObjCMethodWithTypeParams(MD);
CallExpr::const_arg_iterator Arg = ArgRange.begin();
for (QualType Ty : ArgTypes) {
assert(Arg != ArgRange.end() && "Running over edge of argument list!");
QualType ParamTy = Ty.getNonReferenceType();
QualType ArgTy = (*Arg)->getType();
if (const auto *OBT = ParamTy->getAs<OverflowBehaviorType>())
ParamTy = OBT->getUnderlyingType();
if (const auto *OBT = ArgTy->getAs<OverflowBehaviorType>())
ArgTy = OBT->getUnderlyingType();
assert((isGenericMethod || Ty->isVariablyModifiedType() ||
ParamTy->isObjCRetainableType() ||
getContext().getCanonicalType(ParamTy).getTypePtr() ==
getContext().getCanonicalType(ArgTy).getTypePtr()) &&
"type mismatch in call argument!");
++Arg;
}
// Either we've emitted all the call args, or we have a call to variadic
// function.
assert((Arg == ArgRange.end() || IsVariadic) &&
"Extra arguments in non-variadic function!");
#endif
}
// If we still have any arguments, emit them using the type of the argument.
for (auto *A : llvm::drop_begin(ArgRange, ArgTypes.size()))
ArgTypes.push_back(IsVariadic ? getVarArgType(A) : A->getType());
assert((int)ArgTypes.size() == (ArgRange.end() - ArgRange.begin()));
// We must 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 = CodeGenUtils::shouldEvaluateArgsLeftToRight(
Order, CGM.getTarget().getCXXABI());
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.
if (hasInAllocaArgs(CGM, ExplicitCC, ArgTypes)) {
assert(getTarget().getTriple().getArch() == llvm::Triple::x86 &&
"inalloca only supported on 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());
// Reverse the writebacks to match the MSVC ABI.
Args.reverseWritebacks();
}
}
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));
}
}
};
} // end anonymous namespace
RValue CallArg::getRValue(CodeGenFunction &CGF) const {
if (!HasLV)
return RV;
LValue Copy = CGF.MakeAddrLValue(CGF.CreateMemTempWithoutCast(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::EmitWritebacks(const CallArgList &args) {
for (const auto &I : args.writebacks())
emitWriteback(*this, I);
}
void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E,
QualType type) {
std::optional<DisableDebugLocationUpdates> Dis;
if (isa<CXXDefaultArgExpr>(E))
Dis.emplace(*this);
if (const ObjCIndirectCopyRestoreExpr *CRE =
dyn_cast<ObjCIndirectCopyRestoreExpr>(E)) {
assert(getLangOpts().ObjCAutoRefCount);
return emitWritebackArg(*this, args, CRE);
}
// Add writeback for HLSLOutParamExpr.
// Needs to be before the assert below because HLSLOutArgExpr is an LValue
// and is not a reference.
if (const HLSLOutArgExpr *OE = dyn_cast<HLSLOutArgExpr>(E)) {
EmitHLSLOutArgExpr(OE, args, type);
return;
}
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 (type->isRecordType() &&
type->castAsRecordDecl()->isParamDestroyedInCallee()) {
// If we're using inalloca, use the argument memory. Otherwise, use a
// temporary.
AggValueSlot Slot = args.isUsingInAlloca()
? createPlaceholderSlot(*this, type)
: CreateAggTemp(type, "agg.tmp");
bool DestroyedInCallee = true, NeedsCleanup = true;
if (const auto *RD = type->getAsCXXRecordDecl())
DestroyedInCallee = RD->hasNonTrivialDestructor();
else
NeedsCleanup = type.isDestructedType();
if (DestroyedInCallee)
Slot.setExternallyDestructed();
EmitAggExpr(E, Slot);
RValue RV = Slot.asRValue();
args.add(RV, type);
if (DestroyedInCallee && NeedsCleanup) {
// 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>(NormalAndEHCleanup,
Slot.getAddress(), type);
// This unreachable is a temporary marker which will be removed later.
llvm::Instruction *IsActive =
Builder.CreateFlagLoad(llvm::Constant::getNullValue(Int8PtrTy));
args.addArgCleanupDeactivation(EHStack.stable_begin(), IsActive);
}
return;
}
if (HasAggregateEvalKind) {
auto *ICE = dyn_cast<ImplicitCastExpr>(E);
if (ICE && ICE->getCastKind() == CK_LValueToRValue &&
ICE->getSubExpr()->getType().getAddressSpace() !=
LangAS::hlsl_constant &&
!type->isArrayParameterType() && !type.isNonTrivialToPrimitiveCopy()) {
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(LangAS::Default) &&
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, ArrayRef<llvm::Value *>(), name);
}
/// Emits a call to the given nounwind runtime function.
llvm::CallInst *
CodeGenFunction::EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
ArrayRef<Address> args,
const llvm::Twine &name) {
SmallVector<llvm::Value *, 3> values;
for (auto arg : args)
values.push_back(arg.emitRawPointer(*this));
return EmitNounwindRuntimeCall(callee, values, name);
}
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, {}, 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) {
// There is no need for a funclet operand bundle if we aren't inside a
// funclet.
if (!CurrentFuncletPad)
return (SmallVector<llvm::OperandBundleDef, 1>());
// Skip intrinsics which cannot throw (as long as they don't lower into
// regular function calls in the course of IR transformations).
if (auto *CalleeFn = dyn_cast<llvm::Function>(Callee->stripPointerCasts())) {
if (CalleeFn->isIntrinsic() && CalleeFn->doesNotThrow()) {
auto IID = CalleeFn->getIntrinsicID();
if (!llvm::IntrinsicInst::mayLowerToFunctionCall(IID))
return (SmallVector<llvm::OperandBundleDef, 1>());
}
}
SmallVector<llvm::OperandBundleDef, 1> BundleList;
BundleList.emplace_back("funclet", CurrentFuncletPad);
return BundleList;
}
static bool isConvergentIntrinsic(const llvm::Function *F) {
assert(F->isIntrinsic() && "expected an intrinsic declaration");
return F->isConvergent();
}
/// 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,
bool IsConvergent) {
SmallVector<llvm::OperandBundleDef> BundleList =
getBundlesForFunclet(callee.getCallee());
if (IsConvergent)
addConvergenceControlBundle(BundleList);
llvm::CallInst *call = Builder.CreateCall(callee, args, BundleList, name);
call->setCallingConv(getRuntimeCC());
assert((IsConvergent == call->isConvergent() ||
(!IsConvergent && !CGM.shouldEmitConvergenceTokens())) &&
"runtime call convergence doesn't match its declaration");
return call;
}
llvm::CallInst *CodeGenFunction::EmitIntrinsicCall(llvm::Intrinsic::ID ID,
const llvm::Twine &Name) {
return EmitIntrinsicCall(ID, {}, {}, Name);
}
llvm::CallInst *CodeGenFunction::EmitIntrinsicCall(llvm::Intrinsic::ID ID,
ArrayRef<llvm::Value *> Args,
const llvm::Twine &Name) {
return EmitIntrinsicCall(ID, {}, Args, Name);
}
llvm::CallInst *CodeGenFunction::EmitIntrinsicCall(llvm::Intrinsic::ID ID,
ArrayRef<llvm::Type *> Types,
ArrayRef<llvm::Value *> Args,
const llvm::Twine &Name) {
llvm::Function *F =
llvm::Intrinsic::getOrInsertDeclaration(&CGM.getModule(), ID, Types);
SmallVector<llvm::OperandBundleDef> BundleList = getBundlesForFunclet(F);
if (isConvergentIntrinsic(F))
addConvergenceControlBundle(BundleList);
return Builder.CreateCall(F, Args, BundleList, Name);
}
llvm::CallInst *CodeGenFunction::EmitIntrinsicCall(llvm::Intrinsic::ID ID,
ArrayRef<llvm::Value *> Args,
llvm::Type *RetTy,
const llvm::Twine &Name) {
SmallVector<llvm::Type *> ArgTys;
ArgTys.reserve(Args.size());
for (llvm::Value *Arg : Args)
ArgTys.push_back(Arg->getType());
llvm::Function *F = llvm::Intrinsic::getOrInsertDeclaration(
&CGM.getModule(), ID, RetTy, ArgTys);
SmallVector<llvm::OperandBundleDef> BundleList = getBundlesForFunclet(F);
if (isConvergentIntrinsic(F))
addConvergenceControlBundle(BundleList);
return Builder.CreateCall(F, Args, BundleList, Name);
}
/// 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, {}, 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(llvm::WeakTrackingVH(Old), New));
}
namespace {
/// Specify given \p NewAlign as the alignment of return value attribute. If
/// such attribute already exists, re-set it to the maximal one of two options.
[[nodiscard]] llvm::AttributeList
maybeRaiseRetAlignmentAttribute(llvm::LLVMContext &Ctx,
const llvm::AttributeList &Attrs,
llvm::Align NewAlign) {
llvm::Align CurAlign = Attrs.getRetAlignment().valueOrOne();
if (CurAlign >= NewAlign)
return Attrs;
llvm::Attribute AlignAttr = llvm::Attribute::getWithAlignment(Ctx, NewAlign);
return Attrs.removeRetAttribute(Ctx, llvm::Attribute::AttrKind::Alignment)
.addRetAttribute(Ctx, AlignAttr);
}
template <typename AlignedAttrTy> class AbstractAssumeAlignedAttrEmitter {
protected:
CodeGenFunction &CGF;
/// We do nothing if this is, or becomes, nullptr.
const AlignedAttrTy *AA = nullptr;
llvm::Value *Alignment = nullptr; // May or may not be a constant.
llvm::ConstantInt *OffsetCI = nullptr; // Constant, hopefully zero.
AbstractAssumeAlignedAttrEmitter(CodeGenFunction &CGF_, const Decl *FuncDecl)
: CGF(CGF_) {
if (!FuncDecl)
return;
AA = FuncDecl->getAttr<AlignedAttrTy>();
}
public:
/// If we can, materialize the alignment as an attribute on return value.
[[nodiscard]] llvm::AttributeList
TryEmitAsCallSiteAttribute(const llvm::AttributeList &Attrs) {
if (!AA || OffsetCI || CGF.SanOpts.has(SanitizerKind::Alignment))
return Attrs;
const auto *AlignmentCI = dyn_cast<llvm::ConstantInt>(Alignment);
if (!AlignmentCI)
return Attrs;
// We may legitimately have non-power-of-2 alignment here.
// If so, this is UB land, emit it via `@llvm.assume` instead.
if (!AlignmentCI->getValue().isPowerOf2())
return Attrs;
llvm::AttributeList NewAttrs = maybeRaiseRetAlignmentAttribute(
CGF.getLLVMContext(), Attrs,
llvm::Align(
AlignmentCI->getLimitedValue(llvm::Value::MaximumAlignment)));
AA = nullptr; // We're done. Disallow doing anything else.
return NewAttrs;
}
/// Emit alignment assumption.
/// This is a general fallback that we take if either there is an offset,
/// or the alignment is variable or we are sanitizing for alignment.
void EmitAsAnAssumption(SourceLocation Loc, QualType RetTy, RValue &Ret) {
if (!AA)
return;
CGF.emitAlignmentAssumption(Ret.getScalarVal(), RetTy, Loc,
AA->getLocation(), Alignment, OffsetCI);
AA = nullptr; // We're done. Disallow doing anything else.
}
};
/// Helper data structure to emit `AssumeAlignedAttr`.
class AssumeAlignedAttrEmitter final
: public AbstractAssumeAlignedAttrEmitter<AssumeAlignedAttr> {
public:
AssumeAlignedAttrEmitter(CodeGenFunction &CGF_, const Decl *FuncDecl)
: AbstractAssumeAlignedAttrEmitter(CGF_, FuncDecl) {
if (!AA)
return;
// It is guaranteed that the alignment/offset are constants.
Alignment = cast<llvm::ConstantInt>(CGF.EmitScalarExpr(AA->getAlignment()));
if (Expr *Offset = AA->getOffset()) {
OffsetCI = cast<llvm::ConstantInt>(CGF.EmitScalarExpr(Offset));
if (OffsetCI->isNullValue()) // Canonicalize zero offset to no offset.
OffsetCI = nullptr;
}
}
};
/// Helper data structure to emit `AllocAlignAttr`.
class AllocAlignAttrEmitter final
: public AbstractAssumeAlignedAttrEmitter<AllocAlignAttr> {
public:
AllocAlignAttrEmitter(CodeGenFunction &CGF_, const Decl *FuncDecl,
const CallArgList &CallArgs)
: AbstractAssumeAlignedAttrEmitter(CGF_, FuncDecl) {
if (!AA)
return;
// Alignment may or may not be a constant, and that is okay.
Alignment = CallArgs[AA->getParamIndex().getLLVMIndex()]
.getRValue(CGF)
.getScalarVal();
}
};
} // namespace
static unsigned getMaxVectorWidth(const llvm::Type *Ty) {
if (auto *VT = dyn_cast<llvm::VectorType>(Ty))
return VT->getPrimitiveSizeInBits().getKnownMinValue();
if (auto *AT = dyn_cast<llvm::ArrayType>(Ty))
return getMaxVectorWidth(AT->getElementType());
unsigned MaxVectorWidth = 0;
if (auto *ST = dyn_cast<llvm::StructType>(Ty))
for (auto *I : ST->elements())
MaxVectorWidth = std::max(MaxVectorWidth, getMaxVectorWidth(I));
return MaxVectorWidth;
}
RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
const CGCallee &Callee,
ReturnValueSlot ReturnValue,
const CallArgList &CallArgs,
llvm::CallBase **callOrInvoke, bool IsMustTail,
SourceLocation Loc,
bool IsVirtualFunctionPointerThunk) {
// 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>() ||
(CurFuncDecl && CurFuncDecl->hasAttr<TargetAttr>()))) ||
(CurFuncDecl && CurFuncDecl->hasAttr<FlattenAttr>() &&
(CurFuncDecl->hasAttr<TargetAttr>() ||
TargetDecl->hasAttr<TargetAttr>())))
checkTargetFeatures(Loc, FD);
}
// Some architectures (such as x86-64) have the ABI changed based on
// attribute-target/features. Give them a chance to diagnose.
const FunctionDecl *CallerDecl = dyn_cast_or_null<FunctionDecl>(CurCodeDecl);
const FunctionDecl *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl);
CGM.getTargetCodeGenInfo().checkFunctionCallABI(CGM, Loc, CallerDecl,
CalleeDecl, CallArgs, RetTy);
// 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!
RawAddress ArgMemory = RawAddress::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->getIterator());
} else {
AI = CreateTempAlloca(ArgStruct, "argmem");
}
auto Align = CallInfo.getArgStructAlignment();
AI->setAlignment(Align.getAsAlign());
AI->setUsedWithInAlloca(true);
assert(AI->isUsedWithInAlloca() && !AI->isStaticAlloca());
ArgMemory = RawAddress(AI, ArgStruct, 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();
// Original alloca for lifetime markers
Address SRetAlloca = Address::invalid();
bool NeedSRetLifetimeEnd = false;
if (RetAI.isIndirect() || RetAI.isInAlloca() || RetAI.isCoerceAndExpand()) {
// For virtual function pointer thunks and musttail calls, we must always
// forward an incoming SRet pointer to the callee, because a local alloca
// would be de-allocated before the call. These cases both guarantee that
// there will be an incoming SRet argument of the correct type.
if ((IsVirtualFunctionPointerThunk || IsMustTail) && RetAI.isIndirect()) {
SRetPtr = makeNaturalAddressForPointer(CurFn->arg_begin() +
IRFunctionArgs.getSRetArgNo(),
RetTy, CharUnits::fromQuantity(1));
} else if (!ReturnValue.isNull()) {
SRetPtr = ReturnValue.getAddress();
} else {
SRetPtr = CreateMemTempWithoutCast(RetTy, "tmp");
if (HaveInsertPoint() && ReturnValue.isUnused()) {
NeedSRetLifetimeEnd = EmitLifetimeStart(SRetPtr.getBasePointer());
if (NeedSRetLifetimeEnd)
SRetAlloca = SRetPtr;
}
}
if (IRFunctionArgs.hasSRetArg()) {
// A mismatch between the allocated return value's AS and the target's
// chosen IndirectAS can happen e.g. when passing the this pointer through
// a chain involving stores to / loads from the DefaultAS; we address this
// here, symmetrically with the handling we have for normal pointer args.
if (SRetPtr.getAddressSpace() != RetAI.getIndirectAddrSpace()) {
llvm::Value *V = SRetPtr.getBasePointer();
llvm::Type *Ty = llvm::PointerType::get(getLLVMContext(),
RetAI.getIndirectAddrSpace());
SRetPtr = SRetPtr.withPointer(performAddrSpaceCast(V, Ty),
SRetPtr.isKnownNonNull());
}
IRCallArgs[IRFunctionArgs.getSRetArgNo()] =
getAsNaturalPointerTo(SRetPtr, RetTy);
} else if (RetAI.isInAlloca()) {
Address Addr =
Builder.CreateStructGEP(ArgMemory, RetAI.getInAllocaFieldIndex());
Builder.CreateStore(getAsNaturalPointerTo(SRetPtr, RetTy), Addr);
}
}
RawAddress swiftErrorTemp = RawAddress::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<llvm::Value *, 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);
bool ArgHasMaybeUndefAttr =
IsArgumentMaybeUndef(TargetDecl, CallInfo.getNumRequiredArgs(), ArgNo);
switch (ArgInfo.getKind()) {
case ABIArgInfo::InAlloca: {
assert(NumIRArgs == 0);
assert(getTarget().getTriple().getArch() == llvm::Triple::x86);
if (I->isAggregate()) {
RawAddress Addr = I->hasLValue()
? I->getKnownLValue().getAddress()
: I->getKnownRValue().getAggregateAddress();
llvm::Instruction *Placeholder =
cast<llvm::Instruction>(Addr.getPointer());
if (!ArgInfo.getInAllocaIndirect()) {
// Replace the placeholder with the appropriate argument slot GEP.
CGBuilderTy::InsertPoint IP = Builder.saveIP();
Builder.SetInsertPoint(Placeholder);
Addr = Builder.CreateStructGEP(ArgMemory,
ArgInfo.getInAllocaFieldIndex());
Builder.restoreIP(IP);
} else {
// For indirect things such as overaligned structs, replace the
// placeholder with a regular aggregate temporary alloca. Store the
// address of this alloca into the struct.
Addr =
CreateMemTempWithoutCast(info_it->type, "inalloca.indirect.tmp");
Address ArgSlot = Builder.CreateStructGEP(
ArgMemory, ArgInfo.getInAllocaFieldIndex());
Builder.CreateStore(Addr.getPointer(), ArgSlot);
}
deferPlaceholderReplacement(Placeholder, Addr.getPointer());
} else if (ArgInfo.getInAllocaIndirect()) {
// Make a temporary alloca and store the address of it into the argument
// struct.
RawAddress Addr = CreateMemTempWithoutCast(
I->Ty, getContext().getTypeAlignInChars(I->Ty),
"indirect-arg-temp");
I->copyInto(*this, Addr);
Address ArgSlot =
Builder.CreateStructGEP(ArgMemory, ArgInfo.getInAllocaFieldIndex());
Builder.CreateStore(Addr.getPointer(), ArgSlot);
} else {
// Store the RValue into the argument struct.
Address Addr =
Builder.CreateStructGEP(ArgMemory, ArgInfo.getInAllocaFieldIndex());
Addr = Addr.withElementType(ConvertTypeForMem(I->Ty));
I->copyInto(*this, Addr);
}
break;
}
case ABIArgInfo::Indirect:
case ABIArgInfo::IndirectAliased: {
assert(NumIRArgs == 1);
if (I->isAggregate()) {
// 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();
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(Addr.emitRawPointer(*this),
Align.getAsAlign(),
*TD) < Align.getAsAlign()) {
NeedCopy = true;
} else if (I->hasLValue()) {
auto LV = I->getKnownLValue();
bool isByValOrRef =
ArgInfo.isIndirectAliased() || ArgInfo.getIndirectByVal();
if (!isByValOrRef ||
(LV.getAlignment() < getContext().getTypeAlignInChars(I->Ty))) {
NeedCopy = true;
}
if (isByValOrRef && Addr.getType()->getAddressSpace() !=
ArgInfo.getIndirectAddrSpace()) {
NeedCopy = true;
}
}
if (!NeedCopy) {
// Skip the extra memcpy call.
llvm::Value *V = getAsNaturalPointerTo(Addr, I->Ty);
auto *T = llvm::PointerType::get(CGM.getLLVMContext(),
ArgInfo.getIndirectAddrSpace());
// FIXME: This should not depend on the language address spaces, and
// only the contextual values. If the address space mismatches, see if
// we can look through a cast to a compatible address space value,
// otherwise emit a copy.
llvm::Value *Val = performAddrSpaceCast(V, T);
if (ArgHasMaybeUndefAttr)
Val = Builder.CreateFreeze(Val);
IRCallArgs[FirstIRArg] = Val;
break;
}
} else if (I->getType()->isArrayParameterType()) {
// Don't produce a temporary for ArrayParameterType arguments.
// ArrayParameterType arguments are only created from
// HLSL_ArrayRValue casts and HLSLOutArgExpr expressions, both
// of which create temporaries already. This allows us to just use the
// scalar for the decayed array pointer as the argument directly.
IRCallArgs[FirstIRArg] = I->getKnownRValue().getScalarVal();
break;
}
// For non-aggregate args and aggregate args meeting conditions above
// we need to create an aligned temporary, and copy to it.
RawAddress AI = CreateMemTempWithoutCast(
I->Ty, ArgInfo.getIndirectAlign(), "byval-temp");
llvm::Value *Val = getAsNaturalPointerTo(AI, I->Ty);
if (ArgHasMaybeUndefAttr)
Val = Builder.CreateFreeze(Val);
IRCallArgs[FirstIRArg] = Val;
// Emit lifetime markers for the temporary alloca and add cleanup code to
// emit the end lifetime marker after the call.
if (EmitLifetimeStart(AI.getPointer()))
CallLifetimeEndAfterCall.push_back(AI.getPointer());
// Generate the copy.
I->copyInto(*this, AI);
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 = makeNaturalAddressForPointer(
V, pointeeTy, getContext().getTypeAlignInChars(pointeeTy));
swiftErrorTemp = CreateMemTempWithoutCast(
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());
// The only plausible mismatch here would be for pointer address spaces.
// We assume that the target has a reasonable mapping for the DefaultAS
// (it can be casted to from incoming specific ASes), and insert an AS
// cast to address the mismatch.
if (FirstIRArg < IRFuncTy->getNumParams() &&
V->getType() != IRFuncTy->getParamType(FirstIRArg)) {
assert(V->getType()->isPointerTy() && "Only pointers can mismatch!");
V = performAddrSpaceCast(V, IRFuncTy->getParamType(FirstIRArg));
}
if (ArgHasMaybeUndefAttr)
V = Builder.CreateFreeze(V);
IRCallArgs[FirstIRArg] = V;
break;
}
llvm::StructType *STy =
dyn_cast<llvm::StructType>(ArgInfo.getCoerceToType());
// FIXME: Avoid the conversion through memory if possible.
Address Src = Address::invalid();
if (!I->isAggregate()) {
Src = CreateMemTempWithoutCast(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.
if (STy && ArgInfo.isDirect() && ArgInfo.getCanBeFlattened()) {
llvm::Type *SrcTy = Src.getElementType();
llvm::TypeSize SrcTypeSize =
CGM.getDataLayout().getTypeAllocSize(SrcTy);
llvm::TypeSize DstTypeSize = CGM.getDataLayout().getTypeAllocSize(STy);
if (SrcTypeSize.isScalable()) {
assert(STy->containsHomogeneousScalableVectorTypes() &&
"ABI only supports structure with homogeneous scalable vector "
"type");
assert(SrcTypeSize == DstTypeSize &&
"Only allow non-fractional movement of structure with "
"homogeneous scalable vector type");
assert(NumIRArgs == STy->getNumElements());
llvm::Value *StoredStructValue =
Builder.CreateLoad(Src, Src.getName() + ".tuple");
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
llvm::Value *Extract = Builder.CreateExtractValue(
StoredStructValue, i, Src.getName() + ".extract" + Twine(i));
IRCallArgs[FirstIRArg + i] = Extract;
}
} else {
uint64_t SrcSize = SrcTypeSize.getFixedValue();
uint64_t DstSize = DstTypeSize.getFixedValue();
bool HasPFPFields = getContext().hasPFPFields(I->Ty);
// 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 (HasPFPFields || SrcSize < DstSize) {
Address TempAlloca = CreateTempAlloca(STy, Src.getAlignment(),
Src.getName() + ".coerce");
if (HasPFPFields) {
// Structures with PFP fields require a coerced load to remove any
// pointer signatures.
Builder.CreateStore(
CreatePFPCoercedLoad(Src, I->Ty, ArgInfo.getCoerceToType(),
*this),
TempAlloca);
} else
Builder.CreateMemCpy(TempAlloca, Src, SrcSize);
Src = TempAlloca;
} else {
Src = Src.withElementType(STy);
}
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);
if (ArgHasMaybeUndefAttr)
LI = Builder.CreateFreeze(LI);
IRCallArgs[FirstIRArg + i] = LI;
}
}
} else {
// In the simple case, just pass the coerced loaded value.
assert(NumIRArgs == 1);
llvm::Value *Load =
CreateCoercedLoad(Src, I->Ty, ArgInfo.getCoerceToType(), *this);
if (CallInfo.isCmseNSCall()) {
// For certain parameter types, clear padding bits, as they may reveal
// sensitive information.
// Small struct/union types are passed as integer arrays.
auto *ATy = dyn_cast<llvm::ArrayType>(Load->getType());
if (ATy != nullptr && isa<RecordType>(I->Ty.getCanonicalType()))
Load = EmitCMSEClearRecord(Load, ATy, I->Ty);
}
if (ArgHasMaybeUndefAttr)
Load = Builder.CreateFreeze(Load);
IRCallArgs[FirstIRArg] = Load;
}
break;
}
case ABIArgInfo::CoerceAndExpand: {
auto coercionType = ArgInfo.getCoerceAndExpandType();
auto layout = CGM.getDataLayout().getStructLayout(coercionType);
auto unpaddedCoercionType = ArgInfo.getUnpaddedCoerceAndExpandType();
auto *unpaddedStruct = dyn_cast<llvm::StructType>(unpaddedCoercionType);
Address addr = Address::invalid();
RawAddress AllocaAddr = RawAddress::invalid();
bool NeedLifetimeEnd = false;
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 scalarAlign = CGM.getDataLayout().getPrefTypeAlign(scalarType);
// Materialize to a temporary.
addr = CreateTempAlloca(RV.getScalarVal()->getType(),
CharUnits::fromQuantity(std::max(
layout->getAlignment(), scalarAlign)),
"tmp",
/*ArraySize=*/nullptr, &AllocaAddr);
NeedLifetimeEnd = EmitLifetimeStart(AllocaAddr.getPointer());
Builder.CreateStore(RV.getScalarVal(), addr);
}
addr = addr.withElementType(coercionType);
unsigned IRArgPos = FirstIRArg;
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 = CreateCoercedLoad(
eltAddr, I->Ty,
unpaddedStruct ? unpaddedStruct->getElementType(unpaddedIndex++)
: unpaddedCoercionType,
*this);
if (ArgHasMaybeUndefAttr)
elt = Builder.CreateFreeze(elt);
IRCallArgs[IRArgPos++] = elt;
}
assert(IRArgPos == FirstIRArg + NumIRArgs);
if (NeedLifetimeEnd)
EmitLifetimeEnd(AllocaAddr.getPointer());
break;
}
case ABIArgInfo::Expand: {
unsigned IRArgPos = FirstIRArg;
ExpandTypeToArgs(I->Ty, *I, IRFuncTy, IRCallArgs, IRArgPos);
assert(IRArgPos == FirstIRArg + NumIRArgs);
break;
}
case ABIArgInfo::TargetSpecific: {
Address Src = Address::invalid();
if (!I->isAggregate()) {
Src = CreateMemTempWithoutCast(I->Ty, "target_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);
llvm::Value *Load =
CGM.getABIInfo().createCoercedLoad(Src, ArgInfo, *this);
IRCallArgs[FirstIRArg] = Load;
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();
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);
// Update the largest vector width if any arguments have vector types.
for (unsigned i = 0; i < IRCallArgs.size(); ++i)
LargestVectorWidth = std::max(LargestVectorWidth,
getMaxVectorWidth(IRCallArgs[i]->getType()));
// Compute the calling convention and attributes.
unsigned CallingConv;
llvm::AttributeList Attrs;
CGM.ConstructAttributeList(CalleePtr->getName(), CallInfo,
Callee.getAbstractInfo(), Attrs, CallingConv,
/*AttrOnCallSite=*/true,
/*IsThunk=*/false);
if (CallingConv == llvm::CallingConv::X86_VectorCall &&
getTarget().getTriple().isWindowsArm64EC()) {
CGM.Error(Loc, "__vectorcall calling convention is not currently "
"supported");
}
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl)) {
if (FD->hasAttr<StrictFPAttr>())
// All calls within a strictfp function are marked strictfp
Attrs = Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::StrictFP);
// If -ffast-math is enabled and the function is guarded by an
// '__attribute__((optnone)) adjust the memory attribute so the BE emits the
// library call instead of the intrinsic.
if (FD->hasAttr<OptimizeNoneAttr>() && getLangOpts().FastMath)
CGM.AdjustMemoryAttribute(CalleePtr->getName(), Callee.getAbstractInfo(),
Attrs);
}
// Add call-site nomerge attribute if exists.
if (InNoMergeAttributedStmt)
Attrs = Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::NoMerge);
// Add call-site noinline attribute if exists.
if (InNoInlineAttributedStmt)
Attrs = Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::NoInline);
// Add call-site always_inline attribute if exists.
// Note: This corresponds to the [[clang::always_inline]] statement attribute.
if (InAlwaysInlineAttributedStmt &&
!CGM.getTargetCodeGenInfo().wouldInliningViolateFunctionCallABI(
CallerDecl, CalleeDecl))
Attrs =
Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::AlwaysInline);
// 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>() &&
!InNoInlineAttributedStmt &&
!(TargetDecl && TargetDecl->hasAttr<NoInlineAttr>()) &&
!CGM.getTargetCodeGenInfo().wouldInliningViolateFunctionCallABI(
CallerDecl, CalleeDecl)) {
Attrs =
Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::AlwaysInline);
}
// Disable inlining inside SEH __try blocks.
if (isSEHTryScope()) {
Attrs = Attrs.addFnAttribute(getLLVMContext(), 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() &&
getEHPersonality(*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.hasFnAttr(llvm::Attribute::NoUnwind);
if (auto *FPtr = dyn_cast<llvm::Function>(CalleePtr))
if (FPtr->hasFnAttribute(llvm::Attribute::NoUnwind))
CannotThrow = true;
}
// 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.
// Use the original alloca pointer (before any addrspacecast) for the
// lifetime end marker, since lifetime intrinsics must reference the alloca
// address space.
if (NeedSRetLifetimeEnd)
pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, SRetAlloca);
llvm::BasicBlock *InvokeDest = CannotThrow ? nullptr : getInvokeDest();
SmallVector<llvm::OperandBundleDef, 1> BundleList =
getBundlesForFunclet(CalleePtr);
if (SanOpts.has(SanitizerKind::KCFI) &&
!isa_and_nonnull<FunctionDecl>(TargetDecl))
EmitKCFIOperandBundle(ConcreteCallee, BundleList);
// Add the pointer-authentication bundle.
EmitPointerAuthOperandBundle(ConcreteCallee.getPointerAuthInfo(), BundleList);
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl))
if (FD->hasAttr<StrictFPAttr>())
// All calls within a strictfp function are marked strictfp
Attrs = Attrs.addFnAttribute(getLLVMContext(), llvm::Attribute::StrictFP);
AssumeAlignedAttrEmitter AssumeAlignedAttrEmitter(*this, TargetDecl);
Attrs = AssumeAlignedAttrEmitter.TryEmitAsCallSiteAttribute(Attrs);
AllocAlignAttrEmitter AllocAlignAttrEmitter(*this, TargetDecl, CallArgs);
Attrs = AllocAlignAttrEmitter.TryEmitAsCallSiteAttribute(Attrs);
if (Attrs.hasFnAttr(llvm::Attribute::Convergent)) {
addConvergenceControlBundle(BundleList);
// Remove call-site convergent attribute if requested, unless the call must
// stay convergent to match its convergence token and the callee doesn't
// already make it convergent.
//
// FIXME: This means [[clang::noconvergent]] can't make an indirect call
// non-convergent when using convergence tokens. A call without a token can
// later be made direct to a convergent function, which mixes controlled
// and uncontrolled convergence and fails the verifier.
auto *CalleeFn = dyn_cast<llvm::Function>(CalleePtr);
if (InNoConvergentAttributedStmt &&
(!CGM.shouldEmitConvergenceTokens() ||
(CalleeFn && CalleeFn->isConvergent()))) {
Attrs = Attrs.removeFnAttribute(getLLVMContext(),
llvm::Attribute::Convergent);
}
}
// 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 (CI->getCalledFunction() && CI->getCalledFunction()->hasName() &&
CI->getCalledFunction()->getName().starts_with("_Z4sqrt")) {
SetSqrtFPAccuracy(CI);
}
if (callOrInvoke) {
*callOrInvoke = CI;
if (CGM.getCodeGenOpts().CallGraphSection) {
QualType CST;
if (TargetDecl && TargetDecl->getFunctionType())
CST = QualType(TargetDecl->getFunctionType(), 0);
else if (const auto *FPT =
Callee.getAbstractInfo().getCalleeFunctionProtoType())
CST = QualType(FPT, 0);
else if (const auto *FT =
Callee.getAbstractInfo().getCalleeFunctionType())
CST = QualType(FT, 0);
else
llvm_unreachable(
"Cannot find the callee type to generate callee_type metadata.");
// Set type identifier metadata of indirect calls for call graph section.
if (!CST.isNull()) {
if (!CST->isFunctionProtoType()) {
// Reconstruct a prototype for unprototyped callees from the argument
// types passed at the call site (after default argument promotion).
//
// Basic Rationale & K&R-Style Definitions:
// The argument types in CallArgs have already undergone C default
// argument promotion (e.g., char/short -> int, float -> double).
// Furthermore, for a K&R-style
// definition (e.g., void foo(x) short x; { ... }), canonical C ABI
// semantics expect the promoted type (int) at the call boundary
// and implicitly cast down to the declared type (short) inside the
// function. Therefore, signature computation at K&R definition
// sites must also apply default argument promotion (yielding
// void(int), not void(short)) so definition and call sites match.
//
// Signature Strictness & Normalization:
// Since type identifier matching relies on exact hash equality, any
// tolerance for C compatibility rules must be done by normalizing
// types before hashing.
// - Standard C allows certain exceptions for unprototyped calls (and
// variadic va_arg), such as differences in signedness (e.g.,
// passing an int to an unsigned int parameter) or
// interchangeability of enum types with their underlying integer
// types.
// - Existing CFI normalization (e.g.,
// -fsanitize-cfi-icall-experimental-normalize-integers) normalizes
// types by bit-width and signedness (e.g., int vs long on LP64,
// which C does not treat as compatible), but does not normalize
// away signedness or enum mismatches.
// - In the future, whether to normalize away signedness, enums, or
// integer bit-widths depends on whether call graph analysis should
// err on the side of inclusion (admitting any C-valid call) or
// strictness (like CFI). Any normalization applied here at the call
// site must remain strictly matched with definition-site
// type signature computation.
if (const auto *FNPT = CST->getAs<FunctionNoProtoType>()) {
SmallVector<QualType, 8> ParamTypes;
// CallArgs already contains default-promoted argument types for
// unprototyped calls.
for (const CallArg &Arg : CallArgs)
ParamTypes.push_back(Arg.getType());
CST = CGM.ReconstructCallGraphPrototype(FNPT, ParamTypes);
}
llvm::Metadata *MD =
CGM.CreateMetadataIdentifierForCallGraphType(CST);
StringRef TypeStr;
if (auto *MDS = dyn_cast_or_null<llvm::MDString>(MD))
TypeStr = MDS->getString();
CGM.getDiags().Report(Loc, diag::warn_cgs_no_proto) << CST << TypeStr;
}
CGM.createCalleeTypeMetadataForIcall(CST, *callOrInvoke);
}
}
}
// If this is within a function that has the guard(nocf) attribute and is an
// indirect call, add the "guard_nocf" attribute to this call to indicate that
// Control Flow Guard checks should not be added, even if the call is inlined.
if (const auto *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl)) {
if (const auto *A = FD->getAttr<CFGuardAttr>()) {
if (A->getGuard() == CFGuardAttr::GuardArg::nocf &&
!CI->getCalledFunction())
Attrs = Attrs.addFnAttribute(getLLVMContext(), "guard_nocf");
}
}
// 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.
LargestVectorWidth =
std::max(LargestVectorWidth, getMaxVectorWidth(CI->getType()));
// 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);
// Set tail call kind if necessary.
bool IsPPC = getTarget().getTriple().isPPC();
bool IsMIPS = getTarget().getTriple().isMIPS();
bool HasMips16 = false;
if (IsMIPS) {
const TargetOptions &TargetOpts = getTarget().getTargetOpts();
HasMips16 = TargetOpts.FeatureMap.lookup("mips16");
if (!HasMips16)
HasMips16 = llvm::is_contained(TargetOpts.Features, "+mips16");
}
if (llvm::CallInst *Call = dyn_cast<llvm::CallInst>(CI)) {
if (TargetDecl && TargetDecl->hasAttr<NotTailCalledAttr>())
Call->setTailCallKind(llvm::CallInst::TCK_NoTail);
else if (IsMustTail) {
if (IsPPC) {
if (getTarget().getTriple().isOSAIX())
CGM.getDiags().Report(Loc, diag::err_aix_musttail_unsupported);
else if (!getTarget().hasFeature("pcrelative-memops")) {
if (getTarget().hasFeature("longcall"))
CGM.getDiags().Report(Loc, diag::err_ppc_impossible_musttail) << 0;
else if (Call->isIndirectCall())
CGM.getDiags().Report(Loc, diag::err_ppc_impossible_musttail) << 1;
else if (isa_and_nonnull<FunctionDecl>(TargetDecl)) {
if (!cast<FunctionDecl>(TargetDecl)->isDefined())
// The undefined callee may be a forward declaration. Without
// knowning all symbols in the module, we won't know the symbol is
// defined or not. Collect all these symbols for later diagnosing.
CGM.addUndefinedGlobalForTailCall(
{cast<FunctionDecl>(TargetDecl), Loc});
else {
llvm::GlobalValue::LinkageTypes Linkage = CGM.getFunctionLinkage(
GlobalDecl(cast<FunctionDecl>(TargetDecl)));
if (llvm::GlobalValue::isWeakForLinker(Linkage) ||
llvm::GlobalValue::isDiscardableIfUnused(Linkage))
CGM.getDiags().Report(Loc, diag::err_ppc_impossible_musttail)
<< 2;
}
}
}
}
if (IsMIPS) {
if (HasMips16)
CGM.getDiags().Report(Loc, diag::err_mips_impossible_musttail) << 0;
else if (const auto *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
CGM.addUndefinedGlobalForTailCall({FD, Loc});
}
Call->setTailCallKind(llvm::CallInst::TCK_MustTail);
}
}
// Add metadata for calls to MSAllocator functions
if (getDebugInfo() && TargetDecl && TargetDecl->hasAttr<MSAllocatorAttr>())
getDebugInfo()->addHeapAllocSiteMetadata(CI, RetTy->getPointeeType(), Loc);
// Add srcloc metadata for [[gnu::error/warning]] diagnostics. When
// ShowInliningChain is enabled, also track inline/static calls for the
// heuristic fallback when debug info is not available. This heuristic is
// conservative and best-effort since static or inline-annotated functions
// are still not guaranteed to be inlined.
if (TargetDecl) {
bool NeedSrcLoc = TargetDecl->hasAttr<ErrorAttr>();
if (!NeedSrcLoc && CGM.getCodeGenOpts().ShowInliningChain) {
if (const auto *FD = dyn_cast<FunctionDecl>(TargetDecl))
NeedSrcLoc = FD->isInlined() || FD->hasAttr<AlwaysInlineAttr>() ||
FD->getStorageClass() == SC_Static ||
FD->isInAnonymousNamespace();
}
if (NeedSrcLoc) {
auto *Line = llvm::ConstantInt::get(Int64Ty, Loc.getRawEncoding());
auto *MD = llvm::ConstantAsMetadata::get(Line);
CI->setMetadata("srcloc", llvm::MDNode::get(getLLVMContext(), {MD}));
}
}
// 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 (NeedSRetLifetimeEnd)
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->removeFnAttr(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);
}
// If this is a musttail call, return immediately. We do not branch to the
// epilogue in this case.
if (IsMustTail) {
for (auto it = EHStack.find(CurrentCleanupScopeDepth); it != EHStack.end();
++it) {
// A noexcept caller pushes an EHTerminateScope to call std::terminate()
// if an exception escapes. A musttail call replaces the caller's frame,
// removing this handler. This is safe if the callee is also nounwind:
// the callee's own noexcept handler prevents any exception from reaching
// where the caller's handler would have been.
if (isa<EHTerminateScope>(&*it)) {
if (CI->doesNotThrow())
continue;
CGM.getDiags().Report(MustTailCall->getBeginLoc(),
diag::err_musttail_noexcept_mismatch);
break;
}
if (auto *Cleanup = dyn_cast<EHCleanupScope>(&*it)) {
// Fake uses can be safely emitted immediately prior to the tail call,
// so we choose to emit them just before the call here.
if (Cleanup->isFakeUse()) {
CGBuilderTy::InsertPointGuard IPG(Builder);
Builder.SetInsertPoint(CI);
Cleanup->getCleanup()->Emit(*this, EHScopeStack::Cleanup::Flags());
continue;
}
if (Cleanup->isRedundantBeforeReturn())
continue;
}
CGM.ErrorUnsupported(MustTailCall, "tail call skipping over cleanups");
}
if (CI->getType()->isVoidTy())
Builder.CreateRetVoid();
else
Builder.CreateRet(CI);
Builder.ClearInsertionPoint();
EnsureInsertPoint();
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(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;
// If the current function is a virtual function pointer thunk, avoid copying
// the return value of the musttail call to a temporary.
if (IsVirtualFunctionPointerThunk) {
Ret = RValue::get(CI);
} else {
Ret = [&] {
switch (RetAI.getKind()) {
case ABIArgInfo::CoerceAndExpand: {
auto coercionType = RetAI.getCoerceAndExpandType();
Address addr = SRetPtr.withElementType(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]];
}
case ABIArgInfo::InAlloca:
case ABIArgInfo::Indirect: {
RValue ret = convertTempToRValue(SRetPtr, RetTy, SourceLocation());
if (NeedSRetLifetimeEnd)
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:
break;
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);
}
}
}
// If coercing a fixed vector from a scalable vector for ABI
// compatibility, and the types match, use the llvm.vector.extract
// intrinsic to perform the conversion.
if (auto *FixedDstTy = dyn_cast<llvm::FixedVectorType>(RetIRTy)) {
llvm::Value *V = CI;
if (auto *ScalableSrcTy =
dyn_cast<llvm::ScalableVectorType>(V->getType())) {
if (FixedDstTy->getElementType() ==
ScalableSrcTy->getElementType()) {
V = Builder.CreateExtractVector(FixedDstTy, V, uint64_t(0),
"cast.fixed");
return RValue::get(V);
}
}
}
Address DestPtr = ReturnValue.getValue();
bool DestIsVolatile = ReturnValue.isVolatile();
uint64_t DestSize =
getContext().getTypeInfoDataSizeInChars(RetTy).Width.getQuantity();
if (!DestPtr.isValid()) {
DestPtr = CreateMemTempWithoutCast(RetTy, "coerce");
DestIsVolatile = false;
DestSize = getContext().getTypeSizeInChars(RetTy).getQuantity();
}
// An empty record can overlap other data (if declared with
// no_unique_address); omit the store for such types - as there is no
// actual data to store.
if (!isEmptyRecord(getContext(), RetTy, true)) {
// If the value is offset in memory, apply the offset now.
Address StorePtr = emitAddressAtOffset(*this, DestPtr, RetAI);
CreateCoercedStore(
CI, RetTy, StorePtr,
llvm::TypeSize::getFixed(DestSize - RetAI.getDirectOffset()),
DestIsVolatile);
}
return convertTempToRValue(DestPtr, RetTy, SourceLocation());
}
case ABIArgInfo::TargetSpecific: {
Address DestPtr = ReturnValue.getValue();
Address StorePtr = emitAddressAtOffset(*this, DestPtr, RetAI);
bool DestIsVolatile = ReturnValue.isVolatile();
if (!DestPtr.isValid()) {
DestPtr = CreateMemTempWithoutCast(RetTy, "target_coerce");
DestIsVolatile = false;
}
CGM.getABIInfo().createCoercedStore(CI, StorePtr, RetAI, DestIsVolatile,
*this);
return convertTempToRValue(DestPtr, RetTy, SourceLocation());
}
case ABIArgInfo::Expand:
case ABIArgInfo::IndirectAliased:
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) {
AssumeAlignedAttrEmitter.EmitAsAnAssumption(Loc, RetTy, Ret);
AllocAlignAttrEmitter.EmitAsAnAssumption(Loc, RetTy, Ret);
}
// Emit the end lifetime markers for any temporary allocas created for the
// call arguments.
for (llvm::Value *LifetimeEndAddr : CallLifetimeEndAfterCall)
EmitLifetimeEnd(LifetimeEndAddr);
if (!ReturnValue.isExternallyDestructed() &&
RetTy.isDestructedType() == QualType::DK_nontrivial_c_struct)
pushDestroy(QualType::DK_nontrivial_c_struct, Ret.getAggregateAddress(),
RetTy);
// Generate function declaration DISuprogram in order to be used
// in debug info about call sites.
if (CGDebugInfo *DI = getDebugInfo()) {
// Ensure call site info would actually be emitted before collecting
// further callee info.
if (CalleeDecl && !CalleeDecl->hasAttr<NoDebugAttr>() &&
DI->getCallSiteRelatedAttrs() != llvm::DINode::FlagZero) {
CodeGenFunction CalleeCGF(CGM);
const GlobalDecl &CalleeGlobalDecl =
Callee.getAbstractInfo().getCalleeDecl();
CalleeCGF.CurGD = CalleeGlobalDecl;
FunctionArgList Args;
QualType ResTy = CalleeCGF.BuildFunctionArgList(CalleeGlobalDecl, Args);
DI->EmitFuncDeclForCallSite(
CI, DI->getFunctionType(CalleeDecl, ResTy, Args), CalleeGlobalDecl);
}
// Generate call site target information.
DI->addCallTargetIfVirtual(CalleeDecl, CI);
}
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 */
RValue CodeGenFunction::EmitVAArg(VAArgExpr *VE, Address &VAListAddr,
AggValueSlot Slot) {
VAListAddr = VE->isMicrosoftABI()
? EmitMSVAListRef(VE->getSubExpr())
: (VE->isZOSABI() ? EmitZOSVAListRef(VE->getSubExpr())
: EmitVAListRef(VE->getSubExpr()));
QualType Ty = VE->getType();
if (Ty->isVariablyModifiedType())
EmitVariablyModifiedType(Ty);
if (VE->isMicrosoftABI())
return CGM.getABIInfo().EmitMSVAArg(*this, VAListAddr, Ty, Slot);
if (VE->isZOSABI())
return CGM.getABIInfo().EmitZOSVAArg(*this, VAListAddr, Ty, Slot);
return CGM.getABIInfo().EmitVAArg(*this, VAListAddr, Ty, Slot);
}
DisableDebugLocationUpdates::DisableDebugLocationUpdates(CodeGenFunction &CGF)
: CGF(CGF) {
CGF.disableDebugInfo();
}
DisableDebugLocationUpdates::~DisableDebugLocationUpdates() {
CGF.enableDebugInfo();
}