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llvm-project/clang/lib/CodeGen/CGCall.cpp
Akira Hatanaka ed6b578040 [CodeGen] Emit a call instruction instead of an invoke if the called 
llvm function is marked nounwind

This fixes cases where an invoke is emitted, despite the called llvm
function being marked nounwind, because ConstructAttributeList failed to
add the attribute to the attribute list. llvm optimization passes turn
invokes into calls and optimize away the exception handling code, but
it's better to avoid emitting the code in the front-end if the called
function is known not to raise an exception.

Differential Revision: https://reviews.llvm.org/D83906
2020-07-15 14:47:45 -07:00

5134 lines
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//===--- CGCall.cpp - Encapsulate calling convention details --------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// These classes wrap the information about a call or function
// definition used to handle ABI compliancy.
//
//===----------------------------------------------------------------------===//
#include "CGCall.h"
#include "ABIInfo.h"
#include "CGBlocks.h"
#include "CGCXXABI.h"
#include "CGCleanup.h"
#include "CGRecordLayout.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.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/Basic/CodeGenOptions.h"
#include "clang/Basic/TargetBuiltins.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/CodeGen/CGFunctionInfo.h"
#include "clang/CodeGen/SwiftCallingConv.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace clang;
using namespace CodeGen;
/***/
unsigned CodeGenTypes::ClangCallConvToLLVMCallConv(CallingConv CC) {
switch (CC) {
default: return llvm::CallingConv::C;
case CC_X86StdCall: return llvm::CallingConv::X86_StdCall;
case CC_X86FastCall: return llvm::CallingConv::X86_FastCall;
case CC_X86RegCall: return llvm::CallingConv::X86_RegCall;
case CC_X86ThisCall: return llvm::CallingConv::X86_ThisCall;
case CC_Win64: return llvm::CallingConv::Win64;
case CC_X86_64SysV: return llvm::CallingConv::X86_64_SysV;
case CC_AAPCS: return llvm::CallingConv::ARM_AAPCS;
case CC_AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
case CC_IntelOclBicc: return llvm::CallingConv::Intel_OCL_BI;
// TODO: Add support for __pascal to LLVM.
case CC_X86Pascal: return llvm::CallingConv::C;
// TODO: Add support for __vectorcall to LLVM.
case CC_X86VectorCall: return llvm::CallingConv::X86_VectorCall;
case CC_AArch64VectorCall: return llvm::CallingConv::AArch64_VectorCall;
case CC_SpirFunction: return llvm::CallingConv::SPIR_FUNC;
case CC_OpenCLKernel: return CGM.getTargetCodeGenInfo().getOpenCLKernelCallingConv();
case CC_PreserveMost: return llvm::CallingConv::PreserveMost;
case CC_PreserveAll: return llvm::CallingConv::PreserveAll;
case CC_Swift: return llvm::CallingConv::Swift;
}
}
/// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR
/// qualification. Either or both of RD and MD may be null. A null RD indicates
/// that there is no meaningful 'this' type, and a null MD can occur when
/// calling a method pointer.
CanQualType CodeGenTypes::DeriveThisType(const CXXRecordDecl *RD,
const CXXMethodDecl *MD) {
QualType RecTy;
if (RD)
RecTy = Context.getTagDeclType(RD)->getCanonicalTypeInternal();
else
RecTy = Context.VoidTy;
if (MD)
RecTy = Context.getAddrSpaceQualType(RecTy, MD->getMethodQualifiers().getAddressSpace());
return Context.getPointerType(CanQualType::CreateUnsafe(RecTy));
}
/// Returns the canonical formal type of the given C++ method.
static CanQual<FunctionProtoType> GetFormalType(const CXXMethodDecl *MD) {
return MD->getType()->getCanonicalTypeUnqualified()
.getAs<FunctionProtoType>();
}
/// Returns the "extra-canonicalized" return type, which discards
/// qualifiers on the return type. Codegen doesn't care about them,
/// and it makes ABI code a little easier to be able to assume that
/// all parameter and return types are top-level unqualified.
static CanQualType GetReturnType(QualType RetTy) {
return RetTy->getCanonicalTypeUnqualified().getUnqualifiedType();
}
/// Arrange the argument and result information for a value of the given
/// unprototyped freestanding function type.
const CGFunctionInfo &
CodeGenTypes::arrangeFreeFunctionType(CanQual<FunctionNoProtoType> FTNP) {
// When translating an unprototyped function type, always use a
// variadic type.
return arrangeLLVMFunctionInfo(FTNP->getReturnType().getUnqualifiedType(),
/*instanceMethod=*/false,
/*chainCall=*/false, None,
FTNP->getExtInfo(), {}, RequiredArgs(0));
}
static void addExtParameterInfosForCall(
llvm::SmallVectorImpl<FunctionProtoType::ExtParameterInfo> &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().getSizeType());
}
addExtParameterInfosForCall(paramInfos, FPT.getTypePtr(), PrefixSize,
prefix.size());
}
/// Arrange the LLVM function layout for a value of the given function
/// type, on top of any implicit parameters already stored.
static const CGFunctionInfo &
arrangeLLVMFunctionInfo(CodeGenTypes &CGT, bool instanceMethod,
SmallVectorImpl<CanQualType> &prefix,
CanQual<FunctionProtoType> FTP) {
SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
RequiredArgs Required = RequiredArgs::forPrototypePlus(FTP, prefix.size());
// FIXME: Kill copy.
appendParameterTypes(CGT, prefix, paramInfos, FTP);
CanQualType resultType = FTP->getReturnType().getUnqualifiedType();
return CGT.arrangeLLVMFunctionInfo(resultType, instanceMethod,
/*chainCall=*/false, prefix,
FTP->getExtInfo(), paramInfos,
Required);
}
/// Arrange the argument and result information for a value of the
/// given freestanding function type.
const CGFunctionInfo &
CodeGenTypes::arrangeFreeFunctionType(CanQual<FunctionProtoType> FTP) {
SmallVector<CanQualType, 16> argTypes;
return ::arrangeLLVMFunctionInfo(*this, /*instanceMethod=*/false, argTypes,
FTP);
}
static CallingConv getCallingConventionForDecl(const Decl *D, bool IsWindows) {
// Set the appropriate calling convention for the Function.
if (D->hasAttr<StdCallAttr>())
return CC_X86StdCall;
if (D->hasAttr<FastCallAttr>())
return CC_X86FastCall;
if (D->hasAttr<RegCallAttr>())
return CC_X86RegCall;
if (D->hasAttr<ThisCallAttr>())
return CC_X86ThisCall;
if (D->hasAttr<VectorCallAttr>())
return CC_X86VectorCall;
if (D->hasAttr<PascalAttr>())
return CC_X86Pascal;
if (PcsAttr *PCS = D->getAttr<PcsAttr>())
return (PCS->getPCS() == PcsAttr::AAPCS ? CC_AAPCS : CC_AAPCS_VFP);
if (D->hasAttr<AArch64VectorPcsAttr>())
return CC_AArch64VectorCall;
if (D->hasAttr<IntelOclBiccAttr>())
return CC_IntelOclBicc;
if (D->hasAttr<MSABIAttr>())
return IsWindows ? CC_C : CC_Win64;
if (D->hasAttr<SysVABIAttr>())
return IsWindows ? CC_X86_64SysV : CC_C;
if (D->hasAttr<PreserveMostAttr>())
return CC_PreserveMost;
if (D->hasAttr<PreserveAllAttr>())
return CC_PreserveAll;
return CC_C;
}
/// Arrange the argument and result information for a call to an
/// unknown C++ non-static member function of the given abstract type.
/// (A null RD means we don't have any meaningful "this" argument type,
/// so fall back to a generic pointer type).
/// The member function must be an ordinary function, i.e. not a
/// constructor or destructor.
const CGFunctionInfo &
CodeGenTypes::arrangeCXXMethodType(const CXXRecordDecl *RD,
const FunctionProtoType *FTP,
const CXXMethodDecl *MD) {
SmallVector<CanQualType, 16> argTypes;
// Add the 'this' pointer.
argTypes.push_back(DeriveThisType(RD, MD));
return ::arrangeLLVMFunctionInfo(
*this, true, argTypes,
FTP->getCanonicalTypeUnqualified().getAs<FunctionProtoType>());
}
/// Set calling convention for CUDA/HIP kernel.
static void setCUDAKernelCallingConvention(CanQualType &FTy, CodeGenModule &CGM,
const FunctionDecl *FD) {
if (FD->hasAttr<CUDAGlobalAttr>()) {
const FunctionType *FT = FTy->getAs<FunctionType>();
CGM.getTargetCodeGenInfo().setCUDAKernelCallingConvention(FT);
FTy = FT->getCanonicalTypeUnqualified();
}
}
/// Arrange the argument and result information for a declaration or
/// definition of the given C++ non-static member function. The
/// member function must be an ordinary function, i.e. not a
/// constructor or destructor.
const CGFunctionInfo &
CodeGenTypes::arrangeCXXMethodDeclaration(const CXXMethodDecl *MD) {
assert(!isa<CXXConstructorDecl>(MD) && "wrong method for constructors!");
assert(!isa<CXXDestructorDecl>(MD) && "wrong method for destructors!");
CanQualType FT = GetFormalType(MD).getAs<Type>();
setCUDAKernelCallingConvention(FT, CGM, MD);
auto prototype = FT.getAs<FunctionProtoType>();
if (MD->isInstance()) {
// The abstract case is perfectly fine.
const CXXRecordDecl *ThisType = TheCXXABI.getThisArgumentTypeForMethod(MD);
return arrangeCXXMethodType(ThisType, prototype.getTypePtr(), MD);
}
return arrangeFreeFunctionType(prototype);
}
bool CodeGenTypes::inheritingCtorHasParams(
const InheritedConstructor &Inherited, CXXCtorType Type) {
// Parameters are unnecessary if we're constructing a base class subobject
// and the inherited constructor lives in a virtual base.
return Type == Ctor_Complete ||
!Inherited.getShadowDecl()->constructsVirtualBase() ||
!Target.getCXXABI().hasConstructorVariants();
}
const CGFunctionInfo &
CodeGenTypes::arrangeCXXStructorDeclaration(GlobalDecl GD) {
auto *MD = cast<CXXMethodDecl>(GD.getDecl());
SmallVector<CanQualType, 16> argTypes;
SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
argTypes.push_back(DeriveThisType(MD->getParent(), MD));
bool PassParams = true;
if (auto *CD = dyn_cast<CXXConstructorDecl>(MD)) {
// A base class inheriting constructor doesn't get forwarded arguments
// needed to construct a virtual base (or base class thereof).
if (auto Inherited = CD->getInheritedConstructor())
PassParams = inheritingCtorHasParams(Inherited, GD.getCtorType());
}
CanQual<FunctionProtoType> FTP = GetFormalType(MD);
// Add the formal parameters.
if (PassParams)
appendParameterTypes(*this, argTypes, paramInfos, FTP);
CGCXXABI::AddedStructorArgCounts AddedArgs =
TheCXXABI.buildStructorSignature(GD, argTypes);
if (!paramInfos.empty()) {
// Note: prefix implies after the first param.
if (AddedArgs.Prefix)
paramInfos.insert(paramInfos.begin() + 1, AddedArgs.Prefix,
FunctionProtoType::ExtParameterInfo{});
if (AddedArgs.Suffix)
paramInfos.append(AddedArgs.Suffix,
FunctionProtoType::ExtParameterInfo{});
}
RequiredArgs required =
(PassParams && MD->isVariadic() ? RequiredArgs(argTypes.size())
: RequiredArgs::All);
FunctionType::ExtInfo extInfo = FTP->getExtInfo();
CanQualType resultType = TheCXXABI.HasThisReturn(GD)
? argTypes.front()
: TheCXXABI.hasMostDerivedReturn(GD)
? CGM.getContext().VoidPtrTy
: Context.VoidTy;
return arrangeLLVMFunctionInfo(resultType, /*instanceMethod=*/true,
/*chainCall=*/false, argTypes, extInfo,
paramInfos, required);
}
static SmallVector<CanQualType, 16>
getArgTypesForCall(ASTContext &ctx, const CallArgList &args) {
SmallVector<CanQualType, 16> argTypes;
for (auto &arg : args)
argTypes.push_back(ctx.getCanonicalParamType(arg.Ty));
return argTypes;
}
static SmallVector<CanQualType, 16>
getArgTypesForDeclaration(ASTContext &ctx, const FunctionArgList &args) {
SmallVector<CanQualType, 16> argTypes;
for (auto &arg : args)
argTypes.push_back(ctx.getCanonicalParamType(arg->getType()));
return argTypes;
}
static llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16>
getExtParameterInfosForCall(const FunctionProtoType *proto,
unsigned prefixArgs, unsigned totalArgs) {
llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> result;
if (proto->hasExtParameterInfos()) {
addExtParameterInfosForCall(result, proto, prefixArgs, totalArgs);
}
return result;
}
/// Arrange a call to a C++ method, passing the given arguments.
///
/// ExtraPrefixArgs is the number of ABI-specific args passed after the `this`
/// parameter.
/// ExtraSuffixArgs is the number of ABI-specific args passed at the end of
/// args.
/// PassProtoArgs indicates whether `args` has args for the parameters in the
/// given CXXConstructorDecl.
const CGFunctionInfo &
CodeGenTypes::arrangeCXXConstructorCall(const CallArgList &args,
const CXXConstructorDecl *D,
CXXCtorType CtorKind,
unsigned ExtraPrefixArgs,
unsigned ExtraSuffixArgs,
bool PassProtoArgs) {
// FIXME: Kill copy.
SmallVector<CanQualType, 16> ArgTypes;
for (const auto &Arg : args)
ArgTypes.push_back(Context.getCanonicalParamType(Arg.Ty));
// +1 for implicit this, which should always be args[0].
unsigned TotalPrefixArgs = 1 + ExtraPrefixArgs;
CanQual<FunctionProtoType> FPT = GetFormalType(D);
RequiredArgs Required = PassProtoArgs
? RequiredArgs::forPrototypePlus(
FPT, TotalPrefixArgs + ExtraSuffixArgs)
: RequiredArgs::All;
GlobalDecl GD(D, CtorKind);
CanQualType ResultType = TheCXXABI.HasThisReturn(GD)
? ArgTypes.front()
: TheCXXABI.hasMostDerivedReturn(GD)
? CGM.getContext().VoidPtrTy
: Context.VoidTy;
FunctionType::ExtInfo Info = FPT->getExtInfo();
llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> ParamInfos;
// If the prototype args are elided, we should only have ABI-specific args,
// which never have param info.
if (PassProtoArgs && FPT->hasExtParameterInfos()) {
// ABI-specific suffix arguments are treated the same as variadic arguments.
addExtParameterInfosForCall(ParamInfos, FPT.getTypePtr(), TotalPrefixArgs,
ArgTypes.size());
}
return arrangeLLVMFunctionInfo(ResultType, /*instanceMethod=*/true,
/*chainCall=*/false, ArgTypes, Info,
ParamInfos, Required);
}
/// Arrange the argument and result information for the declaration or
/// definition of the given function.
const CGFunctionInfo &
CodeGenTypes::arrangeFunctionDeclaration(const FunctionDecl *FD) {
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
if (MD->isInstance())
return arrangeCXXMethodDeclaration(MD);
CanQualType FTy = FD->getType()->getCanonicalTypeUnqualified();
assert(isa<FunctionType>(FTy));
setCUDAKernelCallingConvention(FTy, CGM, FD);
// When declaring a function without a prototype, always use a
// non-variadic type.
if (CanQual<FunctionNoProtoType> noProto = FTy.getAs<FunctionNoProtoType>()) {
return arrangeLLVMFunctionInfo(
noProto->getReturnType(), /*instanceMethod=*/false,
/*chainCall=*/false, None, noProto->getExtInfo(), {},RequiredArgs::All);
}
return arrangeFreeFunctionType(FTy.castAs<FunctionProtoType>());
}
/// Arrange the argument and result information for the declaration or
/// definition of an Objective-C method.
const CGFunctionInfo &
CodeGenTypes::arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD) {
// It happens that this is the same as a call with no optional
// arguments, except also using the formal 'self' type.
return arrangeObjCMessageSendSignature(MD, MD->getSelfDecl()->getType());
}
/// Arrange the argument and result information for the function type
/// through which to perform a send to the given Objective-C method,
/// using the given receiver type. The receiver type is not always
/// the 'self' type of the method or even an Objective-C pointer type.
/// This is *not* the right method for actually performing such a
/// message send, due to the possibility of optional arguments.
const CGFunctionInfo &
CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD,
QualType receiverType) {
SmallVector<CanQualType, 16> argTys;
SmallVector<FunctionProtoType::ExtParameterInfo, 4> extParamInfos(2);
argTys.push_back(Context.getCanonicalParamType(receiverType));
argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType()));
// FIXME: Kill copy?
for (const auto *I : MD->parameters()) {
argTys.push_back(Context.getCanonicalParamType(I->getType()));
auto extParamInfo = FunctionProtoType::ExtParameterInfo().withIsNoEscape(
I->hasAttr<NoEscapeAttr>());
extParamInfos.push_back(extParamInfo);
}
FunctionType::ExtInfo einfo;
bool IsWindows = getContext().getTargetInfo().getTriple().isOSWindows();
einfo = einfo.withCallingConv(getCallingConventionForDecl(MD, IsWindows));
if (getContext().getLangOpts().ObjCAutoRefCount &&
MD->hasAttr<NSReturnsRetainedAttr>())
einfo = einfo.withProducesResult(true);
RequiredArgs required =
(MD->isVariadic() ? RequiredArgs(argTys.size()) : RequiredArgs::All);
return arrangeLLVMFunctionInfo(
GetReturnType(MD->getReturnType()), /*instanceMethod=*/false,
/*chainCall=*/false, argTys, einfo, extParamInfos, required);
}
const CGFunctionInfo &
CodeGenTypes::arrangeUnprototypedObjCMessageSend(QualType returnType,
const CallArgList &args) {
auto argTypes = getArgTypesForCall(Context, args);
FunctionType::ExtInfo einfo;
return arrangeLLVMFunctionInfo(
GetReturnType(returnType), /*instanceMethod=*/false,
/*chainCall=*/false, argTypes, einfo, {}, RequiredArgs::All);
}
const CGFunctionInfo &
CodeGenTypes::arrangeGlobalDeclaration(GlobalDecl GD) {
// FIXME: Do we need to handle ObjCMethodDecl?
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
if (isa<CXXConstructorDecl>(GD.getDecl()) ||
isa<CXXDestructorDecl>(GD.getDecl()))
return arrangeCXXStructorDeclaration(GD);
return arrangeFunctionDeclaration(FD);
}
/// Arrange a thunk that takes 'this' as the first parameter followed by
/// varargs. Return a void pointer, regardless of the actual return type.
/// The body of the thunk will end in a musttail call to a function of the
/// correct type, and the caller will bitcast the function to the correct
/// prototype.
const CGFunctionInfo &
CodeGenTypes::arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD) {
assert(MD->isVirtual() && "only methods have thunks");
CanQual<FunctionProtoType> FTP = GetFormalType(MD);
CanQualType ArgTys[] = {DeriveThisType(MD->getParent(), MD)};
return arrangeLLVMFunctionInfo(Context.VoidTy, /*instanceMethod=*/false,
/*chainCall=*/false, ArgTys,
FTP->getExtInfo(), {}, RequiredArgs(1));
}
const CGFunctionInfo &
CodeGenTypes::arrangeMSCtorClosure(const CXXConstructorDecl *CD,
CXXCtorType CT) {
assert(CT == Ctor_CopyingClosure || CT == Ctor_DefaultClosure);
CanQual<FunctionProtoType> FTP = GetFormalType(CD);
SmallVector<CanQualType, 2> ArgTys;
const CXXRecordDecl *RD = CD->getParent();
ArgTys.push_back(DeriveThisType(RD, CD));
if (CT == Ctor_CopyingClosure)
ArgTys.push_back(*FTP->param_type_begin());
if (RD->getNumVBases() > 0)
ArgTys.push_back(Context.IntTy);
CallingConv CC = Context.getDefaultCallingConvention(
/*IsVariadic=*/false, /*IsCXXMethod=*/true);
return arrangeLLVMFunctionInfo(Context.VoidTy, /*instanceMethod=*/true,
/*chainCall=*/false, ArgTys,
FunctionType::ExtInfo(CC), {},
RequiredArgs::All);
}
/// Arrange a call as unto a free function, except possibly with an
/// additional number of formal parameters considered required.
static const CGFunctionInfo &
arrangeFreeFunctionLikeCall(CodeGenTypes &CGT,
CodeGenModule &CGM,
const CallArgList &args,
const FunctionType *fnType,
unsigned numExtraRequiredArgs,
bool chainCall) {
assert(args.size() >= numExtraRequiredArgs);
llvm::SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
// In most cases, there are no optional arguments.
RequiredArgs required = RequiredArgs::All;
// If we have a variadic prototype, the required arguments are the
// extra prefix plus the arguments in the prototype.
if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) {
if (proto->isVariadic())
required = RequiredArgs::forPrototypePlus(proto, numExtraRequiredArgs);
if (proto->hasExtParameterInfos())
addExtParameterInfosForCall(paramInfos, proto, numExtraRequiredArgs,
args.size());
// If we don't have a prototype at all, but we're supposed to
// explicitly use the variadic convention for unprototyped calls,
// treat all of the arguments as required but preserve the nominal
// possibility of variadics.
} else if (CGM.getTargetCodeGenInfo()
.isNoProtoCallVariadic(args,
cast<FunctionNoProtoType>(fnType))) {
required = RequiredArgs(args.size());
}
// FIXME: Kill copy.
SmallVector<CanQualType, 16> argTypes;
for (const auto &arg : args)
argTypes.push_back(CGT.getContext().getCanonicalParamType(arg.Ty));
return CGT.arrangeLLVMFunctionInfo(GetReturnType(fnType->getReturnType()),
/*instanceMethod=*/false, chainCall,
argTypes, fnType->getExtInfo(), paramInfos,
required);
}
/// Figure out the rules for calling a function with the given formal
/// type using the given arguments. The arguments are necessary
/// because the function might be unprototyped, in which case it's
/// target-dependent in crazy ways.
const CGFunctionInfo &
CodeGenTypes::arrangeFreeFunctionCall(const CallArgList &args,
const FunctionType *fnType,
bool chainCall) {
return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType,
chainCall ? 1 : 0, chainCall);
}
/// A block function is essentially a free function with an
/// extra implicit argument.
const CGFunctionInfo &
CodeGenTypes::arrangeBlockFunctionCall(const CallArgList &args,
const FunctionType *fnType) {
return arrangeFreeFunctionLikeCall(*this, CGM, args, fnType, 1,
/*chainCall=*/false);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBlockFunctionDeclaration(const FunctionProtoType *proto,
const FunctionArgList &params) {
auto paramInfos = getExtParameterInfosForCall(proto, 1, params.size());
auto argTypes = getArgTypesForDeclaration(Context, params);
return arrangeLLVMFunctionInfo(GetReturnType(proto->getReturnType()),
/*instanceMethod*/ false, /*chainCall*/ false,
argTypes, proto->getExtInfo(), paramInfos,
RequiredArgs::forPrototypePlus(proto, 1));
}
const CGFunctionInfo &
CodeGenTypes::arrangeBuiltinFunctionCall(QualType resultType,
const CallArgList &args) {
// FIXME: Kill copy.
SmallVector<CanQualType, 16> argTypes;
for (const auto &Arg : args)
argTypes.push_back(Context.getCanonicalParamType(Arg.Ty));
return arrangeLLVMFunctionInfo(
GetReturnType(resultType), /*instanceMethod=*/false,
/*chainCall=*/false, argTypes, FunctionType::ExtInfo(),
/*paramInfos=*/ {}, RequiredArgs::All);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBuiltinFunctionDeclaration(QualType resultType,
const FunctionArgList &args) {
auto argTypes = getArgTypesForDeclaration(Context, args);
return arrangeLLVMFunctionInfo(
GetReturnType(resultType), /*instanceMethod=*/false, /*chainCall=*/false,
argTypes, FunctionType::ExtInfo(), {}, RequiredArgs::All);
}
const CGFunctionInfo &
CodeGenTypes::arrangeBuiltinFunctionDeclaration(CanQualType resultType,
ArrayRef<CanQualType> argTypes) {
return arrangeLLVMFunctionInfo(
resultType, /*instanceMethod=*/false, /*chainCall=*/false,
argTypes, FunctionType::ExtInfo(), {}, RequiredArgs::All);
}
/// Arrange a call to a C++ method, passing the given arguments.
///
/// numPrefixArgs is the number of ABI-specific prefix arguments we have. It
/// does not count `this`.
const CGFunctionInfo &
CodeGenTypes::arrangeCXXMethodCall(const CallArgList &args,
const FunctionProtoType *proto,
RequiredArgs required,
unsigned numPrefixArgs) {
assert(numPrefixArgs + 1 <= args.size() &&
"Emitting a call with less args than the required prefix?");
// Add one to account for `this`. It's a bit awkward here, but we don't count
// `this` in similar places elsewhere.
auto paramInfos =
getExtParameterInfosForCall(proto, numPrefixArgs + 1, args.size());
// FIXME: Kill copy.
auto argTypes = getArgTypesForCall(Context, args);
FunctionType::ExtInfo info = proto->getExtInfo();
return arrangeLLVMFunctionInfo(
GetReturnType(proto->getReturnType()), /*instanceMethod=*/true,
/*chainCall=*/false, argTypes, info, paramInfos, required);
}
const CGFunctionInfo &CodeGenTypes::arrangeNullaryFunction() {
return arrangeLLVMFunctionInfo(
getContext().VoidTy, /*instanceMethod=*/false, /*chainCall=*/false,
None, FunctionType::ExtInfo(), {}, RequiredArgs::All);
}
const CGFunctionInfo &
CodeGenTypes::arrangeCall(const CGFunctionInfo &signature,
const CallArgList &args) {
assert(signature.arg_size() <= args.size());
if (signature.arg_size() == args.size())
return signature;
SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
auto sigParamInfos = signature.getExtParameterInfos();
if (!sigParamInfos.empty()) {
paramInfos.append(sigParamInfos.begin(), sigParamInfos.end());
paramInfos.resize(args.size());
}
auto argTypes = getArgTypesForCall(Context, args);
assert(signature.getRequiredArgs().allowsOptionalArgs());
return arrangeLLVMFunctionInfo(signature.getReturnType(),
signature.isInstanceMethod(),
signature.isChainCall(),
argTypes,
signature.getExtInfo(),
paramInfos,
signature.getRequiredArgs());
}
namespace clang {
namespace CodeGen {
void computeSPIRKernelABIInfo(CodeGenModule &CGM, CGFunctionInfo &FI);
}
}
/// Arrange the argument and result information for an abstract value
/// of a given function type. This is the method which all of the
/// above functions ultimately defer to.
const CGFunctionInfo &
CodeGenTypes::arrangeLLVMFunctionInfo(CanQualType resultType,
bool instanceMethod,
bool chainCall,
ArrayRef<CanQualType> argTypes,
FunctionType::ExtInfo info,
ArrayRef<FunctionProtoType::ExtParameterInfo> paramInfos,
RequiredArgs required) {
assert(llvm::all_of(argTypes,
[](CanQualType T) { return T.isCanonicalAsParam(); }));
// Lookup or create unique function info.
llvm::FoldingSetNodeID ID;
CGFunctionInfo::Profile(ID, instanceMethod, chainCall, info, paramInfos,
required, resultType, argTypes);
void *insertPos = nullptr;
CGFunctionInfo *FI = FunctionInfos.FindNodeOrInsertPos(ID, insertPos);
if (FI)
return *FI;
unsigned CC = ClangCallConvToLLVMCallConv(info.getCC());
// Construct the function info. We co-allocate the ArgInfos.
FI = CGFunctionInfo::create(CC, instanceMethod, chainCall, info,
paramInfos, resultType, argTypes, required);
FunctionInfos.InsertNode(FI, insertPos);
bool inserted = FunctionsBeingProcessed.insert(FI).second;
(void)inserted;
assert(inserted && "Recursively being processed?");
// Compute ABI information.
if (CC == llvm::CallingConv::SPIR_KERNEL) {
// Force target independent argument handling for the host visible
// kernel functions.
computeSPIRKernelABIInfo(CGM, *FI);
} else if (info.getCC() == CC_Swift) {
swiftcall::computeABIInfo(CGM, *FI);
} else {
getABIInfo().computeInfo(*FI);
}
// Loop over all of the computed argument and return value info. If any of
// them are direct or extend without a specified coerce type, specify the
// default now.
ABIArgInfo &retInfo = FI->getReturnInfo();
if (retInfo.canHaveCoerceToType() && retInfo.getCoerceToType() == nullptr)
retInfo.setCoerceToType(ConvertType(FI->getReturnType()));
for (auto &I : FI->arguments())
if (I.info.canHaveCoerceToType() && I.info.getCoerceToType() == nullptr)
I.info.setCoerceToType(ConvertType(I.type));
bool erased = FunctionsBeingProcessed.erase(FI); (void)erased;
assert(erased && "Not in set?");
return *FI;
}
CGFunctionInfo *CGFunctionInfo::create(unsigned llvmCC,
bool instanceMethod,
bool chainCall,
const FunctionType::ExtInfo &info,
ArrayRef<ExtParameterInfo> paramInfos,
CanQualType resultType,
ArrayRef<CanQualType> argTypes,
RequiredArgs required) {
assert(paramInfos.empty() || paramInfos.size() == argTypes.size());
assert(!required.allowsOptionalArgs() ||
required.getNumRequiredArgs() <= argTypes.size());
void *buffer =
operator new(totalSizeToAlloc<ArgInfo, ExtParameterInfo>(
argTypes.size() + 1, paramInfos.size()));
CGFunctionInfo *FI = new(buffer) CGFunctionInfo();
FI->CallingConvention = llvmCC;
FI->EffectiveCallingConvention = llvmCC;
FI->ASTCallingConvention = info.getCC();
FI->InstanceMethod = instanceMethod;
FI->ChainCall = chainCall;
FI->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->ArgStruct = nullptr;
FI->ArgStructAlign = 0;
FI->NumArgs = argTypes.size();
FI->HasExtParameterInfos = !paramInfos.empty();
FI->getArgsBuffer()[0].type = resultType;
for (unsigned i = 0, e = argTypes.size(); i != e; ++i)
FI->getArgsBuffer()[i + 1].type = argTypes[i];
for (unsigned i = 0, e = paramInfos.size(); i != e; ++i)
FI->getExtParameterInfosBuffer()[i] = paramInfos[i];
return FI;
}
/***/
namespace {
// ABIArgInfo::Expand implementation.
// Specifies the way QualType passed as ABIArgInfo::Expand is expanded.
struct TypeExpansion {
enum TypeExpansionKind {
// Elements of constant arrays are expanded recursively.
TEK_ConstantArray,
// Record fields are expanded recursively (but if record is a union, only
// the field with the largest size is expanded).
TEK_Record,
// For complex types, real and imaginary parts are expanded recursively.
TEK_Complex,
// All other types are not expandable.
TEK_None
};
const TypeExpansionKind Kind;
TypeExpansion(TypeExpansionKind K) : Kind(K) {}
virtual ~TypeExpansion() {}
};
struct ConstantArrayExpansion : TypeExpansion {
QualType EltTy;
uint64_t NumElts;
ConstantArrayExpansion(QualType EltTy, uint64_t NumElts)
: TypeExpansion(TEK_ConstantArray), EltTy(EltTy), NumElts(NumElts) {}
static bool classof(const TypeExpansion *TE) {
return TE->Kind == TEK_ConstantArray;
}
};
struct RecordExpansion : TypeExpansion {
SmallVector<const CXXBaseSpecifier *, 1> Bases;
SmallVector<const FieldDecl *, 1> Fields;
RecordExpansion(SmallVector<const CXXBaseSpecifier *, 1> &&Bases,
SmallVector<const FieldDecl *, 1> &&Fields)
: TypeExpansion(TEK_Record), Bases(std::move(Bases)),
Fields(std::move(Fields)) {}
static bool classof(const TypeExpansion *TE) {
return TE->Kind == TEK_Record;
}
};
struct ComplexExpansion : TypeExpansion {
QualType EltTy;
ComplexExpansion(QualType EltTy) : TypeExpansion(TEK_Complex), EltTy(EltTy) {}
static bool classof(const TypeExpansion *TE) {
return TE->Kind == TEK_Complex;
}
};
struct NoExpansion : TypeExpansion {
NoExpansion() : TypeExpansion(TEK_None) {}
static bool classof(const TypeExpansion *TE) {
return TE->Kind == TEK_None;
}
};
} // namespace
static std::unique_ptr<TypeExpansion>
getTypeExpansion(QualType Ty, const ASTContext &Context) {
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
return std::make_unique<ConstantArrayExpansion>(
AT->getElementType(), AT->getSize().getZExtValue());
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
SmallVector<const CXXBaseSpecifier *, 1> Bases;
SmallVector<const FieldDecl *, 1> Fields;
const RecordDecl *RD = RT->getDecl();
assert(!RD->hasFlexibleArrayMember() &&
"Cannot expand structure with flexible array.");
if (RD->isUnion()) {
// Unions can be here only in degenerative cases - all the fields are same
// after flattening. Thus we have to use the "largest" field.
const FieldDecl *LargestFD = nullptr;
CharUnits UnionSize = CharUnits::Zero();
for (const auto *FD : RD->fields()) {
if (FD->isZeroLengthBitField(Context))
continue;
assert(!FD->isBitField() &&
"Cannot expand structure with bit-field members.");
CharUnits FieldSize = Context.getTypeSizeInChars(FD->getType());
if (UnionSize < FieldSize) {
UnionSize = FieldSize;
LargestFD = FD;
}
}
if (LargestFD)
Fields.push_back(LargestFD);
} else {
if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
assert(!CXXRD->isDynamicClass() &&
"cannot expand vtable pointers in dynamic classes");
for (const CXXBaseSpecifier &BS : CXXRD->bases())
Bases.push_back(&BS);
}
for (const auto *FD : RD->fields()) {
if (FD->isZeroLengthBitField(Context))
continue;
assert(!FD->isBitField() &&
"Cannot expand structure with bit-field members.");
Fields.push_back(FD);
}
}
return std::make_unique<RecordExpansion>(std::move(Bases),
std::move(Fields));
}
if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
return std::make_unique<ComplexExpansion>(CT->getElementType());
}
return std::make_unique<NoExpansion>();
}
static int getExpansionSize(QualType Ty, const ASTContext &Context) {
auto Exp = getTypeExpansion(Ty, Context);
if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) {
return CAExp->NumElts * getExpansionSize(CAExp->EltTy, Context);
}
if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) {
int Res = 0;
for (auto BS : RExp->Bases)
Res += getExpansionSize(BS->getType(), Context);
for (auto FD : RExp->Fields)
Res += getExpansionSize(FD->getType(), Context);
return Res;
}
if (isa<ComplexExpansion>(Exp.get()))
return 2;
assert(isa<NoExpansion>(Exp.get()));
return 1;
}
void
CodeGenTypes::getExpandedTypes(QualType Ty,
SmallVectorImpl<llvm::Type *>::iterator &TI) {
auto Exp = getTypeExpansion(Ty, Context);
if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) {
for (int i = 0, n = CAExp->NumElts; i < n; i++) {
getExpandedTypes(CAExp->EltTy, TI);
}
} else if (auto RExp = dyn_cast<RecordExpansion>(Exp.get())) {
for (auto BS : RExp->Bases)
getExpandedTypes(BS->getType(), TI);
for (auto FD : RExp->Fields)
getExpandedTypes(FD->getType(), TI);
} else if (auto CExp = dyn_cast<ComplexExpansion>(Exp.get())) {
llvm::Type *EltTy = ConvertType(CExp->EltTy);
*TI++ = EltTy;
*TI++ = EltTy;
} else {
assert(isa<NoExpansion>(Exp.get()));
*TI++ = ConvertType(Ty);
}
}
static void forConstantArrayExpansion(CodeGenFunction &CGF,
ConstantArrayExpansion *CAE,
Address BaseAddr,
llvm::function_ref<void(Address)> Fn) {
CharUnits EltSize = CGF.getContext().getTypeSizeInChars(CAE->EltTy);
CharUnits EltAlign =
BaseAddr.getAlignment().alignmentOfArrayElement(EltSize);
for (int i = 0, n = CAE->NumElts; i < n; i++) {
llvm::Value *EltAddr =
CGF.Builder.CreateConstGEP2_32(nullptr, BaseAddr.getPointer(), 0, i);
Fn(Address(EltAddr, EltAlign));
}
}
void CodeGenFunction::ExpandTypeFromArgs(QualType Ty, LValue LV,
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(*this), [&](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(*this);
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()));
if (LV.isBitField())
EmitStoreThroughLValue(RValue::get(&*AI++), LV);
else
EmitStoreOfScalar(&*AI++, LV);
}
}
void CodeGenFunction::ExpandTypeToArgs(
QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy,
SmallVectorImpl<llvm::Value *> &IRCallArgs, unsigned &IRCallArgPos) {
auto Exp = getTypeExpansion(Ty, getContext());
if (auto CAExp = dyn_cast<ConstantArrayExpansion>(Exp.get())) {
Address Addr = Arg.hasLValue() ? Arg.getKnownLValue().getAddress(*this)
: 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(*this)
: Arg.getKnownRValue().getAggregateAddress();
for (const CXXBaseSpecifier *BS : RExp->Bases) {
// Perform a single step derived-to-base conversion.
Address Base =
GetAddressOfBaseClass(This, Ty->getAsCXXRecordDecl(), &BS, &BS + 1,
/*NullCheckValue=*/false, SourceLocation());
CallArg BaseArg = CallArg(RValue::getAggregate(Base), BS->getType());
// Recurse onto bases.
ExpandTypeToArgs(BS->getType(), BaseArg, IRFuncTy, IRCallArgs,
IRCallArgPos);
}
LValue LV = MakeAddrLValue(This, Ty);
for (auto FD : RExp->Fields) {
CallArg FldArg =
CallArg(EmitRValueForField(LV, FD, SourceLocation()), FD->getType());
ExpandTypeToArgs(FD->getType(), FldArg, IRFuncTy, IRCallArgs,
IRCallArgPos);
}
} else if (isa<ComplexExpansion>(Exp.get())) {
ComplexPairTy CV = Arg.getKnownRValue().getComplexVal();
IRCallArgs[IRCallArgPos++] = CV.first;
IRCallArgs[IRCallArgPos++] = CV.second;
} else {
assert(isa<NoExpansion>(Exp.get()));
auto RV = Arg.getKnownRValue();
assert(RV.isScalar() &&
"Unexpected non-scalar rvalue during struct expansion.");
// Insert a bitcast as needed.
llvm::Value *V = RV.getScalarVal();
if (IRCallArgPos < IRFuncTy->getNumParams() &&
V->getType() != IRFuncTy->getParamType(IRCallArgPos))
V = Builder.CreateBitCast(V, IRFuncTy->getParamType(IRCallArgPos));
IRCallArgs[IRCallArgPos++] = V;
}
}
/// Create a temporary allocation for the purposes of coercion.
static Address CreateTempAllocaForCoercion(CodeGenFunction &CGF, llvm::Type *Ty,
CharUnits MinAlign) {
// Don't use an alignment that's worse than what LLVM would prefer.
auto PrefAlign = CGF.CGM.getDataLayout().getPrefTypeAlignment(Ty);
CharUnits Align = std::max(MinAlign, CharUnits::fromQuantity(PrefAlign));
return CGF.CreateTempAlloca(Ty, Align);
}
/// EnterStructPointerForCoercedAccess - Given a struct pointer that we are
/// accessing some number of bytes out of it, try to gep into the struct to get
/// at its inner goodness. Dive as deep as possible without entering an element
/// with an in-memory size smaller than DstSize.
static Address
EnterStructPointerForCoercedAccess(Address SrcPtr,
llvm::StructType *SrcSTy,
uint64_t DstSize, CodeGenFunction &CGF) {
// We can't dive into a zero-element struct.
if (SrcSTy->getNumElements() == 0) return SrcPtr;
llvm::Type *FirstElt = SrcSTy->getElementType(0);
// If the first elt is at least as large as what we're looking for, or if the
// first element is the same size as the whole struct, we can enter it. The
// comparison must be made on the store size and not the alloca size. Using
// the alloca size may overstate the size of the load.
uint64_t FirstEltSize =
CGF.CGM.getDataLayout().getTypeStoreSize(FirstElt);
if (FirstEltSize < DstSize &&
FirstEltSize < CGF.CGM.getDataLayout().getTypeStoreSize(SrcSTy))
return SrcPtr;
// GEP into the first element.
SrcPtr = CGF.Builder.CreateStructGEP(SrcPtr, 0, "coerce.dive");
// If the first element is a struct, recurse.
llvm::Type *SrcTy = SrcPtr.getElementType();
if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy))
return EnterStructPointerForCoercedAccess(SrcPtr, SrcSTy, DstSize, CGF);
return SrcPtr;
}
/// CoerceIntOrPtrToIntOrPtr - Convert a value Val to the specific Ty where both
/// are either integers or pointers. This does a truncation of the value if it
/// is too large or a zero extension if it is too small.
///
/// This behaves as if the value were coerced through memory, so on big-endian
/// targets the high bits are preserved in a truncation, while little-endian
/// targets preserve the low bits.
static llvm::Value *CoerceIntOrPtrToIntOrPtr(llvm::Value *Val,
llvm::Type *Ty,
CodeGenFunction &CGF) {
if (Val->getType() == Ty)
return Val;
if (isa<llvm::PointerType>(Val->getType())) {
// If this is Pointer->Pointer avoid conversion to and from int.
if (isa<llvm::PointerType>(Ty))
return CGF.Builder.CreateBitCast(Val, Ty, "coerce.val");
// Convert the pointer to an integer so we can play with its width.
Val = CGF.Builder.CreatePtrToInt(Val, CGF.IntPtrTy, "coerce.val.pi");
}
llvm::Type *DestIntTy = Ty;
if (isa<llvm::PointerType>(DestIntTy))
DestIntTy = CGF.IntPtrTy;
if (Val->getType() != DestIntTy) {
const llvm::DataLayout &DL = CGF.CGM.getDataLayout();
if (DL.isBigEndian()) {
// Preserve the high bits on big-endian targets.
// That is what memory coercion does.
uint64_t SrcSize = DL.getTypeSizeInBits(Val->getType());
uint64_t DstSize = DL.getTypeSizeInBits(DestIntTy);
if (SrcSize > DstSize) {
Val = CGF.Builder.CreateLShr(Val, SrcSize - DstSize, "coerce.highbits");
Val = CGF.Builder.CreateTrunc(Val, DestIntTy, "coerce.val.ii");
} else {
Val = CGF.Builder.CreateZExt(Val, DestIntTy, "coerce.val.ii");
Val = CGF.Builder.CreateShl(Val, DstSize - SrcSize, "coerce.highbits");
}
} else {
// Little-endian targets preserve the low bits. No shifts required.
Val = CGF.Builder.CreateIntCast(Val, DestIntTy, false, "coerce.val.ii");
}
}
if (isa<llvm::PointerType>(Ty))
Val = CGF.Builder.CreateIntToPtr(Val, Ty, "coerce.val.ip");
return Val;
}
/// CreateCoercedLoad - Create a load from \arg SrcPtr interpreted as
/// a pointer to an object of type \arg Ty, known to be aligned to
/// \arg SrcAlign bytes.
///
/// This safely handles the case when the src type is smaller than the
/// destination type; in this situation the values of bits which not
/// present in the src are undefined.
static llvm::Value *CreateCoercedLoad(Address Src, llvm::Type *Ty,
CodeGenFunction &CGF) {
llvm::Type *SrcTy = Src.getElementType();
// If SrcTy and Ty are the same, just do a load.
if (SrcTy == Ty)
return CGF.Builder.CreateLoad(Src);
uint64_t DstSize = CGF.CGM.getDataLayout().getTypeAllocSize(Ty);
if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy)) {
Src = EnterStructPointerForCoercedAccess(Src, SrcSTy, DstSize, CGF);
SrcTy = Src.getElementType();
}
uint64_t SrcSize = CGF.CGM.getDataLayout().getTypeAllocSize(SrcTy);
// If the source and destination are integer or pointer types, just do an
// extension or truncation to the desired type.
if ((isa<llvm::IntegerType>(Ty) || isa<llvm::PointerType>(Ty)) &&
(isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy))) {
llvm::Value *Load = CGF.Builder.CreateLoad(Src);
return CoerceIntOrPtrToIntOrPtr(Load, Ty, CGF);
}
// If load is legal, just bitcast the src pointer.
if (SrcSize >= DstSize) {
// Generally SrcSize is never greater than DstSize, since this means we are
// losing bits. However, this can happen in cases where the structure has
// additional padding, for example due to a user specified alignment.
//
// FIXME: Assert that we aren't truncating non-padding bits when have access
// to that information.
Src = CGF.Builder.CreateBitCast(Src,
Ty->getPointerTo(Src.getAddressSpace()));
return CGF.Builder.CreateLoad(Src);
}
// Otherwise do coercion through memory. This is stupid, but simple.
Address Tmp = CreateTempAllocaForCoercion(CGF, Ty, Src.getAlignment());
CGF.Builder.CreateMemCpy(Tmp.getPointer(), Tmp.getAlignment().getAsAlign(),
Src.getPointer(), Src.getAlignment().getAsAlign(),
llvm::ConstantInt::get(CGF.IntPtrTy, SrcSize));
return CGF.Builder.CreateLoad(Tmp);
}
// Function to store a first-class aggregate into memory. We prefer to
// store the elements rather than the aggregate to be more friendly to
// fast-isel.
// FIXME: Do we need to recurse here?
void CodeGenFunction::EmitAggregateStore(llvm::Value *Val, Address Dest,
bool DestIsVolatile) {
// Prefer scalar stores to first-class aggregate stores.
if (llvm::StructType *STy = dyn_cast<llvm::StructType>(Val->getType())) {
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
Address EltPtr = Builder.CreateStructGEP(Dest, i);
llvm::Value *Elt = Builder.CreateExtractValue(Val, i);
Builder.CreateStore(Elt, EltPtr, DestIsVolatile);
}
} else {
Builder.CreateStore(Val, Dest, DestIsVolatile);
}
}
/// CreateCoercedStore - Create a store to \arg DstPtr from \arg Src,
/// where the source and destination may have different types. The
/// destination is known to be aligned to \arg DstAlign bytes.
///
/// This safely handles the case when the src type is larger than the
/// destination type; the upper bits of the src will be lost.
static void CreateCoercedStore(llvm::Value *Src,
Address Dst,
bool DstIsVolatile,
CodeGenFunction &CGF) {
llvm::Type *SrcTy = Src->getType();
llvm::Type *DstTy = Dst.getElementType();
if (SrcTy == DstTy) {
CGF.Builder.CreateStore(Src, Dst, DstIsVolatile);
return;
}
uint64_t SrcSize = CGF.CGM.getDataLayout().getTypeAllocSize(SrcTy);
if (llvm::StructType *DstSTy = dyn_cast<llvm::StructType>(DstTy)) {
Dst = EnterStructPointerForCoercedAccess(Dst, DstSTy, SrcSize, CGF);
DstTy = Dst.getElementType();
}
llvm::PointerType *SrcPtrTy = llvm::dyn_cast<llvm::PointerType>(SrcTy);
llvm::PointerType *DstPtrTy = llvm::dyn_cast<llvm::PointerType>(DstTy);
if (SrcPtrTy && DstPtrTy &&
SrcPtrTy->getAddressSpace() != DstPtrTy->getAddressSpace()) {
Src = CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(Src, DstTy);
CGF.Builder.CreateStore(Src, Dst, DstIsVolatile);
return;
}
// If the source and destination are integer or pointer types, just do an
// extension or truncation to the desired type.
if ((isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy)) &&
(isa<llvm::IntegerType>(DstTy) || isa<llvm::PointerType>(DstTy))) {
Src = CoerceIntOrPtrToIntOrPtr(Src, DstTy, CGF);
CGF.Builder.CreateStore(Src, Dst, DstIsVolatile);
return;
}
uint64_t DstSize = CGF.CGM.getDataLayout().getTypeAllocSize(DstTy);
// If store is legal, just bitcast the src pointer.
if (SrcSize <= DstSize) {
Dst = CGF.Builder.CreateElementBitCast(Dst, SrcTy);
CGF.EmitAggregateStore(Src, Dst, DstIsVolatile);
} else {
// Otherwise do coercion through memory. This is stupid, but
// simple.
// Generally SrcSize is never greater than DstSize, since this means we are
// losing bits. However, this can happen in cases where the structure has
// additional padding, for example due to a user specified alignment.
//
// FIXME: Assert that we aren't truncating non-padding bits when have access
// to that information.
Address Tmp = CreateTempAllocaForCoercion(CGF, SrcTy, Dst.getAlignment());
CGF.Builder.CreateStore(Src, Tmp);
CGF.Builder.CreateMemCpy(Dst.getPointer(), Dst.getAlignment().getAsAlign(),
Tmp.getPointer(), Tmp.getAlignment().getAsAlign(),
llvm::ConstantInt::get(CGF.IntPtrTy, DstSize));
}
}
static Address emitAddressAtOffset(CodeGenFunction &CGF, Address addr,
const ABIArgInfo &info) {
if (unsigned offset = info.getDirectOffset()) {
addr = CGF.Builder.CreateElementBitCast(addr, CGF.Int8Ty);
addr = CGF.Builder.CreateConstInBoundsByteGEP(addr,
CharUnits::fromQuantity(offset));
addr = CGF.Builder.CreateElementBitCast(addr, info.getCoerceToType());
}
return addr;
}
namespace {
/// Encapsulates information about the way function arguments from
/// CGFunctionInfo should be passed to actual LLVM IR function.
class ClangToLLVMArgMapping {
static const unsigned InvalidIndex = ~0U;
unsigned InallocaArgNo;
unsigned SRetArgNo;
unsigned TotalIRArgs;
/// Arguments of LLVM IR function corresponding to single Clang argument.
struct IRArgs {
unsigned PaddingArgIndex;
// Argument is expanded to IR arguments at positions
// [FirstArgIndex, FirstArgIndex + NumberOfArgs).
unsigned FirstArgIndex;
unsigned NumberOfArgs;
IRArgs()
: PaddingArgIndex(InvalidIndex), FirstArgIndex(InvalidIndex),
NumberOfArgs(0) {}
};
SmallVector<IRArgs, 8> ArgInfo;
public:
ClangToLLVMArgMapping(const ASTContext &Context, const CGFunctionInfo &FI,
bool OnlyRequiredArgs = false)
: InallocaArgNo(InvalidIndex), SRetArgNo(InvalidIndex), TotalIRArgs(0),
ArgInfo(OnlyRequiredArgs ? FI.getNumRequiredArgs() : FI.arg_size()) {
construct(Context, FI, OnlyRequiredArgs);
}
bool hasInallocaArg() const { return InallocaArgNo != InvalidIndex; }
unsigned getInallocaArgNo() const {
assert(hasInallocaArg());
return InallocaArgNo;
}
bool hasSRetArg() const { return SRetArgNo != InvalidIndex; }
unsigned getSRetArgNo() const {
assert(hasSRetArg());
return SRetArgNo;
}
unsigned totalIRArgs() const { return TotalIRArgs; }
bool hasPaddingArg(unsigned ArgNo) const {
assert(ArgNo < ArgInfo.size());
return ArgInfo[ArgNo].PaddingArgIndex != InvalidIndex;
}
unsigned getPaddingArgNo(unsigned ArgNo) const {
assert(hasPaddingArg(ArgNo));
return ArgInfo[ArgNo].PaddingArgIndex;
}
/// Returns index of first IR argument corresponding to ArgNo, and their
/// quantity.
std::pair<unsigned, unsigned> getIRArgs(unsigned ArgNo) const {
assert(ArgNo < ArgInfo.size());
return std::make_pair(ArgInfo[ArgNo].FirstArgIndex,
ArgInfo[ArgNo].NumberOfArgs);
}
private:
void construct(const ASTContext &Context, const CGFunctionInfo &FI,
bool OnlyRequiredArgs);
};
void ClangToLLVMArgMapping::construct(const ASTContext &Context,
const CGFunctionInfo &FI,
bool OnlyRequiredArgs) {
unsigned IRArgNo = 0;
bool SwapThisWithSRet = false;
const ABIArgInfo &RetAI = FI.getReturnInfo();
if (RetAI.getKind() == ABIArgInfo::Indirect) {
SwapThisWithSRet = RetAI.isSRetAfterThis();
SRetArgNo = SwapThisWithSRet ? 1 : IRArgNo++;
}
unsigned ArgNo = 0;
unsigned NumArgs = OnlyRequiredArgs ? FI.getNumRequiredArgs() : FI.arg_size();
for (CGFunctionInfo::const_arg_iterator I = FI.arg_begin(); ArgNo < NumArgs;
++I, ++ArgNo) {
assert(I != FI.arg_end());
QualType ArgType = I->type;
const ABIArgInfo &AI = I->info;
// Collect data about IR arguments corresponding to Clang argument ArgNo.
auto &IRArgs = ArgInfo[ArgNo];
if (AI.getPaddingType())
IRArgs.PaddingArgIndex = IRArgNo++;
switch (AI.getKind()) {
case ABIArgInfo::Extend:
case ABIArgInfo::Direct: {
// FIXME: handle sseregparm someday...
llvm::StructType *STy = dyn_cast<llvm::StructType>(AI.getCoerceToType());
if (AI.isDirect() && AI.getCanBeFlattened() && STy) {
IRArgs.NumberOfArgs = STy->getNumElements();
} else {
IRArgs.NumberOfArgs = 1;
}
break;
}
case ABIArgInfo::Indirect:
IRArgs.NumberOfArgs = 1;
break;
case ABIArgInfo::Ignore:
case ABIArgInfo::InAlloca:
// ignore and inalloca doesn't have matching LLVM parameters.
IRArgs.NumberOfArgs = 0;
break;
case ABIArgInfo::CoerceAndExpand:
IRArgs.NumberOfArgs = AI.getCoerceAndExpandTypeSequence().size();
break;
case ABIArgInfo::Expand:
IRArgs.NumberOfArgs = getExpansionSize(ArgType, Context);
break;
}
if (IRArgs.NumberOfArgs > 0) {
IRArgs.FirstArgIndex = IRArgNo;
IRArgNo += IRArgs.NumberOfArgs;
}
// Skip over the sret parameter when it comes second. We already handled it
// above.
if (IRArgNo == 1 && SwapThisWithSRet)
IRArgNo++;
}
assert(ArgNo == ArgInfo.size());
if (FI.usesInAlloca())
InallocaArgNo = IRArgNo++;
TotalIRArgs = IRArgNo;
}
} // namespace
/***/
bool CodeGenModule::ReturnTypeUsesSRet(const CGFunctionInfo &FI) {
const auto &RI = FI.getReturnInfo();
return RI.isIndirect() || (RI.isInAlloca() && RI.getInAllocaSRet());
}
bool CodeGenModule::ReturnSlotInterferesWithArgs(const CGFunctionInfo &FI) {
return ReturnTypeUsesSRet(FI) &&
getTargetCodeGenInfo().doesReturnSlotInterfereWithArgs();
}
bool CodeGenModule::ReturnTypeUsesFPRet(QualType ResultType) {
if (const BuiltinType *BT = ResultType->getAs<BuiltinType>()) {
switch (BT->getKind()) {
default:
return false;
case BuiltinType::Float:
return getTarget().useObjCFPRetForRealType(TargetInfo::Float);
case BuiltinType::Double:
return getTarget().useObjCFPRetForRealType(TargetInfo::Double);
case BuiltinType::LongDouble:
return getTarget().useObjCFPRetForRealType(TargetInfo::LongDouble);
}
}
return false;
}
bool CodeGenModule::ReturnTypeUsesFP2Ret(QualType ResultType) {
if (const ComplexType *CT = ResultType->getAs<ComplexType>()) {
if (const BuiltinType *BT = CT->getElementType()->getAs<BuiltinType>()) {
if (BT->getKind() == BuiltinType::LongDouble)
return getTarget().useObjCFP2RetForComplexLongDouble();
}
}
return false;
}
llvm::FunctionType *CodeGenTypes::GetFunctionType(GlobalDecl GD) {
const CGFunctionInfo &FI = arrangeGlobalDeclaration(GD);
return GetFunctionType(FI);
}
llvm::FunctionType *
CodeGenTypes::GetFunctionType(const CGFunctionInfo &FI) {
bool Inserted = FunctionsBeingProcessed.insert(&FI).second;
(void)Inserted;
assert(Inserted && "Recursively being processed?");
llvm::Type *resultType = nullptr;
const ABIArgInfo &retAI = FI.getReturnInfo();
switch (retAI.getKind()) {
case ABIArgInfo::Expand:
llvm_unreachable("Invalid ABI kind for return argument");
case ABIArgInfo::Extend:
case ABIArgInfo::Direct:
resultType = retAI.getCoerceToType();
break;
case ABIArgInfo::InAlloca:
if (retAI.getInAllocaSRet()) {
// sret things on win32 aren't void, they return the sret pointer.
QualType ret = FI.getReturnType();
llvm::Type *ty = ConvertType(ret);
unsigned addressSpace = Context.getTargetAddressSpace(ret);
resultType = llvm::PointerType::get(ty, addressSpace);
} else {
resultType = llvm::Type::getVoidTy(getLLVMContext());
}
break;
case ABIArgInfo::Indirect:
case ABIArgInfo::Ignore:
resultType = llvm::Type::getVoidTy(getLLVMContext());
break;
case ABIArgInfo::CoerceAndExpand:
resultType = retAI.getUnpaddedCoerceAndExpandType();
break;
}
ClangToLLVMArgMapping IRFunctionArgs(getContext(), FI, true);
SmallVector<llvm::Type*, 8> ArgTypes(IRFunctionArgs.totalIRArgs());
// Add type for sret argument.
if (IRFunctionArgs.hasSRetArg()) {
QualType Ret = FI.getReturnType();
llvm::Type *Ty = ConvertType(Ret);
unsigned AddressSpace = Context.getTargetAddressSpace(Ret);
ArgTypes[IRFunctionArgs.getSRetArgNo()] =
llvm::PointerType::get(Ty, AddressSpace);
}
// Add type for inalloca argument.
if (IRFunctionArgs.hasInallocaArg()) {
auto ArgStruct = FI.getArgStruct();
assert(ArgStruct);
ArgTypes[IRFunctionArgs.getInallocaArgNo()] = ArgStruct->getPointerTo();
}
// Add in all of the required arguments.
unsigned ArgNo = 0;
CGFunctionInfo::const_arg_iterator it = FI.arg_begin(),
ie = it + FI.getNumRequiredArgs();
for (; it != ie; ++it, ++ArgNo) {
const ABIArgInfo &ArgInfo = it->info;
// Insert a padding type to ensure proper alignment.
if (IRFunctionArgs.hasPaddingArg(ArgNo))
ArgTypes[IRFunctionArgs.getPaddingArgNo(ArgNo)] =
ArgInfo.getPaddingType();
unsigned FirstIRArg, NumIRArgs;
std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
switch (ArgInfo.getKind()) {
case ABIArgInfo::Ignore:
case ABIArgInfo::InAlloca:
assert(NumIRArgs == 0);
break;
case ABIArgInfo::Indirect: {
assert(NumIRArgs == 1);
// indirect arguments are always on the stack, which is alloca addr space.
llvm::Type *LTy = ConvertTypeForMem(it->type);
ArgTypes[FirstIRArg] = LTy->getPointerTo(
CGM.getDataLayout().getAllocaAddrSpace());
break;
}
case ABIArgInfo::Extend:
case ABIArgInfo::Direct: {
// Fast-isel and the optimizer generally like scalar values better than
// FCAs, so we flatten them if this is safe to do for this argument.
llvm::Type *argType = ArgInfo.getCoerceToType();
llvm::StructType *st = dyn_cast<llvm::StructType>(argType);
if (st && ArgInfo.isDirect() && ArgInfo.getCanBeFlattened()) {
assert(NumIRArgs == st->getNumElements());
for (unsigned i = 0, e = st->getNumElements(); i != e; ++i)
ArgTypes[FirstIRArg + i] = st->getElementType(i);
} else {
assert(NumIRArgs == 1);
ArgTypes[FirstIRArg] = argType;
}
break;
}
case ABIArgInfo::CoerceAndExpand: {
auto ArgTypesIter = ArgTypes.begin() + FirstIRArg;
for (auto EltTy : ArgInfo.getCoerceAndExpandTypeSequence()) {
*ArgTypesIter++ = EltTy;
}
assert(ArgTypesIter == ArgTypes.begin() + FirstIRArg + NumIRArgs);
break;
}
case ABIArgInfo::Expand:
auto ArgTypesIter = ArgTypes.begin() + FirstIRArg;
getExpandedTypes(it->type, ArgTypesIter);
assert(ArgTypesIter == ArgTypes.begin() + FirstIRArg + NumIRArgs);
break;
}
}
bool Erased = FunctionsBeingProcessed.erase(&FI); (void)Erased;
assert(Erased && "Not in set?");
return llvm::FunctionType::get(resultType, ArgTypes, FI.isVariadic());
}
llvm::Type *CodeGenTypes::GetFunctionTypeForVTable(GlobalDecl GD) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
if (!isFuncTypeConvertible(FPT))
return llvm::StructType::get(getLLVMContext());
return GetFunctionType(GD);
}
static void AddAttributesFromFunctionProtoType(ASTContext &Ctx,
llvm::AttrBuilder &FuncAttrs,
const FunctionProtoType *FPT) {
if (!FPT)
return;
if (!isUnresolvedExceptionSpec(FPT->getExceptionSpecType()) &&
FPT->isNothrow())
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
}
void CodeGenModule::getDefaultFunctionAttributes(StringRef Name,
bool HasOptnone,
bool AttrOnCallSite,
llvm::AttrBuilder &FuncAttrs) {
// OptimizeNoneAttr takes precedence over -Os or -Oz. No warning needed.
if (!HasOptnone) {
if (CodeGenOpts.OptimizeSize)
FuncAttrs.addAttribute(llvm::Attribute::OptimizeForSize);
if (CodeGenOpts.OptimizeSize == 2)
FuncAttrs.addAttribute(llvm::Attribute::MinSize);
}
if (CodeGenOpts.DisableRedZone)
FuncAttrs.addAttribute(llvm::Attribute::NoRedZone);
if (CodeGenOpts.IndirectTlsSegRefs)
FuncAttrs.addAttribute("indirect-tls-seg-refs");
if (CodeGenOpts.NoImplicitFloat)
FuncAttrs.addAttribute(llvm::Attribute::NoImplicitFloat);
if (AttrOnCallSite) {
// Attributes that should go on the call site only.
if (!CodeGenOpts.SimplifyLibCalls ||
CodeGenOpts.isNoBuiltinFunc(Name.data()))
FuncAttrs.addAttribute(llvm::Attribute::NoBuiltin);
if (!CodeGenOpts.TrapFuncName.empty())
FuncAttrs.addAttribute("trap-func-name", CodeGenOpts.TrapFuncName);
} else {
StringRef FpKind;
switch (CodeGenOpts.getFramePointer()) {
case CodeGenOptions::FramePointerKind::None:
FpKind = "none";
break;
case CodeGenOptions::FramePointerKind::NonLeaf:
FpKind = "non-leaf";
break;
case CodeGenOptions::FramePointerKind::All:
FpKind = "all";
break;
}
FuncAttrs.addAttribute("frame-pointer", FpKind);
FuncAttrs.addAttribute("less-precise-fpmad",
llvm::toStringRef(CodeGenOpts.LessPreciseFPMAD));
if (CodeGenOpts.NullPointerIsValid)
FuncAttrs.addAttribute(llvm::Attribute::NullPointerIsValid);
if (CodeGenOpts.FPDenormalMode != llvm::DenormalMode::getIEEE())
FuncAttrs.addAttribute("denormal-fp-math",
CodeGenOpts.FPDenormalMode.str());
if (CodeGenOpts.FP32DenormalMode != CodeGenOpts.FPDenormalMode) {
FuncAttrs.addAttribute(
"denormal-fp-math-f32",
CodeGenOpts.FP32DenormalMode.str());
}
FuncAttrs.addAttribute("no-trapping-math",
llvm::toStringRef(LangOpts.getFPExceptionMode() ==
LangOptions::FPE_Ignore));
// Strict (compliant) code is the default, so only add this attribute to
// indicate that we are trying to workaround a problem case.
if (!CodeGenOpts.StrictFloatCastOverflow)
FuncAttrs.addAttribute("strict-float-cast-overflow", "false");
// TODO: Are these all needed?
// unsafe/inf/nan/nsz are handled by instruction-level FastMathFlags.
FuncAttrs.addAttribute("no-infs-fp-math",
llvm::toStringRef(LangOpts.NoHonorInfs));
FuncAttrs.addAttribute("no-nans-fp-math",
llvm::toStringRef(LangOpts.NoHonorNaNs));
FuncAttrs.addAttribute("unsafe-fp-math",
llvm::toStringRef(LangOpts.UnsafeFPMath));
FuncAttrs.addAttribute("use-soft-float",
llvm::toStringRef(CodeGenOpts.SoftFloat));
FuncAttrs.addAttribute("stack-protector-buffer-size",
llvm::utostr(CodeGenOpts.SSPBufferSize));
FuncAttrs.addAttribute("no-signed-zeros-fp-math",
llvm::toStringRef(LangOpts.NoSignedZero));
FuncAttrs.addAttribute(
"correctly-rounded-divide-sqrt-fp-math",
llvm::toStringRef(CodeGenOpts.CorrectlyRoundedDivSqrt));
// 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);
}
if (getLangOpts().assumeFunctionsAreConvergent()) {
// Conservatively, mark all functions and calls in CUDA and OpenCL as
// convergent (meaning, they may call an intrinsically convergent op, such
// as __syncthreads() / barrier(), and so can't have certain optimizations
// applied around them). LLVM will remove this attribute where it safely
// can.
FuncAttrs.addAttribute(llvm::Attribute::Convergent);
}
if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
// Exceptions aren't supported in CUDA device code.
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
}
for (StringRef Attr : CodeGenOpts.DefaultFunctionAttrs) {
StringRef Var, Value;
std::tie(Var, Value) = Attr.split('=');
FuncAttrs.addAttribute(Var, Value);
}
}
void CodeGenModule::addDefaultFunctionDefinitionAttributes(llvm::Function &F) {
llvm::AttrBuilder FuncAttrs;
getDefaultFunctionAttributes(F.getName(), F.hasOptNone(),
/* AttrOnCallSite = */ false, FuncAttrs);
// TODO: call GetCPUAndFeaturesAttributes?
F.addAttributes(llvm::AttributeList::FunctionIndex, 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);
}
/// 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) {
llvm::AttrBuilder FuncAttrs;
llvm::AttrBuilder RetAttrs;
// 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();
bool HasOptnone = false;
// The NoBuiltinAttr attached to the target FunctionDecl.
const NoBuiltinAttr *NBA = nullptr;
// 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<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.
auto Kind = Fn->getDeclName().getCXXOverloadedOperator();
if (getCodeGenOpts().AssumeSaneOperatorNew &&
(Kind == OO_New || Kind == OO_Array_New))
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>();
}
}
// 'const', 'pure' and 'noalias' attributed functions are also nounwind.
if (TargetDecl->hasAttr<ConstAttr>()) {
FuncAttrs.addAttribute(llvm::Attribute::ReadNone);
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
} else if (TargetDecl->hasAttr<PureAttr>()) {
FuncAttrs.addAttribute(llvm::Attribute::ReadOnly);
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
} else if (TargetDecl->hasAttr<NoAliasAttr>()) {
FuncAttrs.addAttribute(llvm::Attribute::ArgMemOnly);
FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
}
if (TargetDecl->hasAttr<RestrictAttr>())
RetAttrs.addAttribute(llvm::Attribute::NoAlias);
if (TargetDecl->hasAttr<ReturnsNonNullAttr>() &&
!CodeGenOpts.NullPointerIsValid)
RetAttrs.addAttribute(llvm::Attribute::NonNull);
if (TargetDecl->hasAttr<AnyX86NoCallerSavedRegistersAttr>())
FuncAttrs.addAttribute("no_caller_saved_registers");
if (TargetDecl->hasAttr<AnyX86NoCfCheckAttr>())
FuncAttrs.addAttribute(llvm::Attribute::NoCfCheck);
HasOptnone = TargetDecl->hasAttr<OptimizeNoneAttr>();
if (auto *AllocSize = TargetDecl->getAttr<AllocSizeAttr>()) {
Optional<unsigned> NumElemsParam;
if (AllocSize->getNumElemsParam().isValid())
NumElemsParam = AllocSize->getNumElemsParam().getLLVMIndex();
FuncAttrs.addAllocSizeAttr(AllocSize->getElemSizeParam().getLLVMIndex(),
NumElemsParam);
}
if (TargetDecl->hasAttr<OpenCLKernelAttr>()) {
if (getLangOpts().OpenCLVersion <= 120) {
// OpenCL v1.2 Work groups are always uniform
FuncAttrs.addAttribute("uniform-work-group-size", "true");
} else {
// OpenCL v2.0 Work groups may be whether uniform or not.
// '-cl-uniform-work-group-size' compile option gets a hint
// to the compiler that the global work-size be a multiple of
// the work-group size specified to clEnqueueNDRangeKernel
// (i.e. work groups are uniform).
FuncAttrs.addAttribute("uniform-work-group-size",
llvm::toStringRef(CodeGenOpts.UniformWGSize));
}
}
}
// 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");
// 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);
}
}
}
}
// 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;
};
FuncAttrs.addAttribute("disable-tail-calls",
llvm::toStringRef(shouldDisableTailCalls()));
// CPU/feature overrides. addDefaultFunctionDefinitionAttributes
// handles these separately to set them based on the global defaults.
GetCPUAndFeaturesAttributes(CalleeInfo.getCalleeDecl(), FuncAttrs);
}
// Collect attributes from arguments and return values.
ClangToLLVMArgMapping IRFunctionArgs(getContext(), FI);
QualType RetTy = FI.getReturnType();
const ABIArgInfo &RetAI = FI.getReturnInfo();
switch (RetAI.getKind()) {
case ABIArgInfo::Extend:
if (RetAI.isSignExt())
RetAttrs.addAttribute(llvm::Attribute::SExt);
else
RetAttrs.addAttribute(llvm::Attribute::ZExt);
LLVM_FALLTHROUGH;
case ABIArgInfo::Direct:
if (RetAI.getInReg())
RetAttrs.addAttribute(llvm::Attribute::InReg);
break;
case ABIArgInfo::Ignore:
break;
case ABIArgInfo::InAlloca:
case ABIArgInfo::Indirect: {
// inalloca and sret disable readnone and readonly
FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly)
.removeAttribute(llvm::Attribute::ReadNone);
break;
}
case ABIArgInfo::CoerceAndExpand:
break;
case ABIArgInfo::Expand:
llvm_unreachable("Invalid ABI kind for return argument");
}
if (const auto *RefTy = RetTy->getAs<ReferenceType>()) {
QualType PTy = RefTy->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType())
RetAttrs.addDereferenceableAttr(
getMinimumObjectSize(PTy).getQuantity());
if (getContext().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::AttributeSet, 4> ArgAttrs(IRFunctionArgs.totalIRArgs());
// Attach attributes to sret.
if (IRFunctionArgs.hasSRetArg()) {
llvm::AttrBuilder SRETAttrs;
SRETAttrs.addAttribute(llvm::Attribute::StructRet);
hasUsedSRet = true;
if (RetAI.getInReg())
SRETAttrs.addAttribute(llvm::Attribute::InReg);
SRETAttrs.addAlignmentAttr(RetAI.getIndirectAlign().getQuantity());
ArgAttrs[IRFunctionArgs.getSRetArgNo()] =
llvm::AttributeSet::get(getLLVMContext(), SRETAttrs);
}
// Attach attributes to inalloca argument.
if (IRFunctionArgs.hasInallocaArg()) {
llvm::AttrBuilder Attrs;
Attrs.addAttribute(llvm::Attribute::InAlloca);
ArgAttrs[IRFunctionArgs.getInallocaArgNo()] =
llvm::AttributeSet::get(getLLVMContext(), Attrs);
}
unsigned ArgNo = 0;
for (CGFunctionInfo::const_arg_iterator I = FI.arg_begin(),
E = FI.arg_end();
I != E; ++I, ++ArgNo) {
QualType ParamType = I->type;
const ABIArgInfo &AI = I->info;
llvm::AttrBuilder Attrs;
// Add attribute for padding argument, if necessary.
if (IRFunctionArgs.hasPaddingArg(ArgNo)) {
if (AI.getPaddingInReg()) {
ArgAttrs[IRFunctionArgs.getPaddingArgNo(ArgNo)] =
llvm::AttributeSet::get(
getLLVMContext(),
llvm::AttrBuilder().addAttribute(llvm::Attribute::InReg));
}
}
// 'restrict' -> 'noalias' is done in EmitFunctionProlog when we
// have the corresponding parameter variable. It doesn't make
// sense to do it here because parameters are so messed up.
switch (AI.getKind()) {
case ABIArgInfo::Extend:
if (AI.isSignExt())
Attrs.addAttribute(llvm::Attribute::SExt);
else
Attrs.addAttribute(llvm::Attribute::ZExt);
LLVM_FALLTHROUGH;
case ABIArgInfo::Direct:
if (ArgNo == 0 && FI.isChainCall())
Attrs.addAttribute(llvm::Attribute::Nest);
else if (AI.getInReg())
Attrs.addAttribute(llvm::Attribute::InReg);
break;
case ABIArgInfo::Indirect: {
if (AI.getInReg())
Attrs.addAttribute(llvm::Attribute::InReg);
if (AI.getIndirectByVal())
Attrs.addByValAttr(getTypes().ConvertTypeForMem(ParamType));
CharUnits Align = AI.getIndirectAlign();
// In a byval argument, it is important that the required
// alignment of the type is honored, as LLVM might be creating a
// *new* stack object, and needs to know what alignment to give
// it. (Sometimes it can deduce a sensible alignment on its own,
// but not if clang decides it must emit a packed struct, or the
// user specifies increased alignment requirements.)
//
// This is different from indirect *not* byval, where the object
// exists already, and the align attribute is purely
// informative.
assert(!Align.isZero());
// For now, only add this when we have a byval argument.
// TODO: be less lazy about updating test cases.
if (AI.getIndirectByVal())
Attrs.addAlignmentAttr(Align.getQuantity());
// byval disables readnone and readonly.
FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly)
.removeAttribute(llvm::Attribute::ReadNone);
break;
}
case ABIArgInfo::Ignore:
case ABIArgInfo::Expand:
case ABIArgInfo::CoerceAndExpand:
break;
case ABIArgInfo::InAlloca:
// inalloca disables readnone and readonly.
FuncAttrs.removeAttribute(llvm::Attribute::ReadOnly)
.removeAttribute(llvm::Attribute::ReadNone);
continue;
}
if (const auto *RefTy = ParamType->getAs<ReferenceType>()) {
QualType PTy = RefTy->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType())
Attrs.addDereferenceableAttr(
getMinimumObjectSize(PTy).getQuantity());
if (getContext().getTargetAddressSpace(PTy) == 0 &&
!CodeGenOpts.NullPointerIsValid)
Attrs.addAttribute(llvm::Attribute::NonNull);
if (PTy->isObjectType()) {
llvm::Align Alignment =
getNaturalPointeeTypeAlignment(ParamType).getAsAlign();
Attrs.addAlignmentAttr(Alignment);
}
}
switch (FI.getExtParameterInfo(ArgNo).getABI()) {
case ParameterABI::Ordinary:
break;
case ParameterABI::SwiftIndirectResult: {
// Add 'sret' if we haven't already used it for something, but
// only if the result is void.
if (!hasUsedSRet && RetTy->isVoidType()) {
Attrs.addAttribute(llvm::Attribute::StructRet);
hasUsedSRet = true;
}
// Add 'noalias' in either case.
Attrs.addAttribute(llvm::Attribute::NoAlias);
// Add 'dereferenceable' and 'alignment'.
auto PTy = ParamType->getPointeeType();
if (!PTy->isIncompleteType() && PTy->isConstantSizeType()) {
auto info = getContext().getTypeInfoInChars(PTy);
Attrs.addDereferenceableAttr(info.first.getQuantity());
Attrs.addAlignmentAttr(info.second.getAsAlign());
}
break;
}
case ParameterABI::SwiftErrorResult:
Attrs.addAttribute(llvm::Attribute::SwiftError);
break;
case ParameterABI::SwiftContext:
Attrs.addAttribute(llvm::Attribute::SwiftSelf);
break;
}
if (FI.getExtParameterInfo(ArgNo).isNoEscape())
Attrs.addAttribute(llvm::Attribute::NoCapture);
if (Attrs.hasAttributes()) {
unsigned FirstIRArg, NumIRArgs;
std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
for (unsigned i = 0; i < NumIRArgs; i++)
ArgAttrs[FirstIRArg + i] =
llvm::AttributeSet::get(getLLVMContext(), Attrs);
}
}
assert(ArgNo == FI.arg_size());
AttrList = llvm::AttributeList::get(
getLLVMContext(), llvm::AttributeSet::get(getLLVMContext(), FuncAttrs),
llvm::AttributeSet::get(getLLVMContext(), RetAttrs), ArgAttrs);
}
/// An argument came in as a promoted argument; demote it back to its
/// declared type.
static llvm::Value *emitArgumentDemotion(CodeGenFunction &CGF,
const VarDecl *var,
llvm::Value *value) {
llvm::Type *varType = CGF.ConvertType(var->getType());
// This can happen with promotions that actually don't change the
// underlying type, like the enum promotions.
if (value->getType() == varType) return value;
assert((varType->isIntegerTy() || varType->isFloatingPointTy())
&& "unexpected promotion type");
if (isa<llvm::IntegerType>(varType))
return CGF.Builder.CreateTrunc(value, varType, "arg.unpromote");
return CGF.Builder.CreateFPCast(value, varType, "arg.unpromote");
}
/// Returns the attribute (either parameter attribute, or function
/// attribute), which declares argument ArgNo to be non-null.
static const NonNullAttr *getNonNullAttr(const Decl *FD, const ParmVarDecl *PVD,
QualType ArgType, unsigned ArgNo) {
// FIXME: __attribute__((nonnull)) can also be applied to:
// - references to pointers, where the pointee is known to be
// nonnull (apparently a Clang extension)
// - transparent unions containing pointers
// In the former case, LLVM IR cannot represent the constraint. In
// the latter case, we have no guarantee that the transparent union
// is in fact passed as a pointer.
if (!ArgType->isAnyPointerType() && !ArgType->isBlockPointerType())
return nullptr;
// First, check attribute on parameter itself.
if (PVD) {
if (auto ParmNNAttr = PVD->getAttr<NonNullAttr>())
return ParmNNAttr;
}
// Check function attributes.
if (!FD)
return nullptr;
for (const auto *NNAttr : FD->specific_attrs<NonNullAttr>()) {
if (NNAttr->isNonNull(ArgNo))
return NNAttr;
}
return nullptr;
}
namespace {
struct CopyBackSwiftError final : EHScopeStack::Cleanup {
Address Temp;
Address Arg;
CopyBackSwiftError(Address temp, Address arg) : Temp(temp), Arg(arg) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
llvm::Value *errorValue = CGF.Builder.CreateLoad(Temp);
CGF.Builder.CreateStore(errorValue, Arg);
}
};
}
void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI,
llvm::Function *Fn,
const FunctionArgList &Args) {
if (CurCodeDecl && CurCodeDecl->hasAttr<NakedAttr>())
// Naked functions don't have prologues.
return;
// If this is an implicit-return-zero function, go ahead and
// initialize the return value. TODO: it might be nice to have
// a more general mechanism for this that didn't require synthesized
// return statements.
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurCodeDecl)) {
if (FD->hasImplicitReturnZero()) {
QualType RetTy = FD->getReturnType().getUnqualifiedType();
llvm::Type* LLVMTy = CGM.getTypes().ConvertType(RetTy);
llvm::Constant* Zero = llvm::Constant::getNullValue(LLVMTy);
Builder.CreateStore(Zero, ReturnValue);
}
}
// FIXME: We no longer need the types from FunctionArgList; lift up and
// simplify.
ClangToLLVMArgMapping IRFunctionArgs(CGM.getContext(), FI);
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.getArgStructAlignment());
assert(ArgStruct.getType() == FI.getArgStruct()->getPointerTo());
}
// 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),
getContext().getTypeAlignInChars(Ty));
ArgVals.push_back(ParamValue::forIndirect(V));
break;
}
case ABIArgInfo::Indirect: {
assert(NumIRArgs == 1);
Address ParamAddr =
Address(Fn->getArg(FirstIRArg), ArgI.getIndirectAlign());
if (!hasScalarEvaluationKind(Ty)) {
// Aggregates and complex variables are accessed by reference. All we
// need to do is realign the value, if requested.
Address V = ParamAddr;
if (ArgI.getIndirectRealign()) {
Address AlignedTemp = CreateMemTemp(Ty, "coerce");
// Copy from the incoming argument pointer to the temporary with the
// appropriate alignment.
//
// FIXME: We should have a common utility for generating an aggregate
// copy.
CharUnits Size = getContext().getTypeSizeInChars(Ty);
Builder.CreateMemCpy(
AlignedTemp.getPointer(), AlignedTemp.getAlignment().getAsAlign(),
ParamAddr.getPointer(), ParamAddr.getAlignment().getAsAlign(),
llvm::ConstantInt::get(IntPtrTy, Size.getQuantity()));
V = AlignedTemp;
}
ArgVals.push_back(ParamValue::forIndirect(V));
} else {
// Load scalar value from indirect argument.
llvm::Value *V =
EmitLoadOfScalar(ParamAddr, false, Ty, Arg->getBeginLoc());
if (isPromoted)
V = emitArgumentDemotion(*this, Arg, V);
ArgVals.push_back(ParamValue::forDirect(V));
}
break;
}
case ABIArgInfo::Extend:
case ABIArgInfo::Direct: {
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() == ArrayType::Static) {
QualType ETy = ArrTy->getElementType();
uint64_t ArrSize = ArrTy->getSize().getZExtValue();
if (!ETy->isIncompleteType() && ETy->isConstantSizeType() &&
ArrSize) {
llvm::AttrBuilder Attrs;
Attrs.addDereferenceableAttr(
getContext().getTypeSizeInChars(ETy).getQuantity() *
ArrSize);
AI->addAttrs(Attrs);
} else if (getContext().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() == VariableArrayType::Static &&
!getContext().getTargetAddressSpace(ArrTy->getElementType()) &&
!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 = dyn_cast<TypedefType>(OTy))
AVAttr = TOTy->getDecl()->getAttr<AlignValueAttr>();
if (AVAttr && !SanOpts.has(SanitizerKind::Alignment)) {
// If alignment-assumption sanitizer is enabled, we do *not* add
// alignment attribute here, but emit normal alignment assumption,
// so the UBSAN check could function.
llvm::ConstantInt *AlignmentCI =
cast<llvm::ConstantInt>(EmitScalarExpr(AVAttr->getAlignment()));
unsigned AlignmentInt =
AlignmentCI->getLimitedValue(llvm::Value::MaximumAlignment);
if (AI->getParamAlign().valueOrOne() < AlignmentInt) {
AI->removeAttr(llvm::Attribute::AttrKind::Alignment);
AI->addAttrs(llvm::AttrBuilder().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());
Address temp =
CreateMemTemp(pointeeTy, getPointerAlign(), "swifterror.temp");
Address arg = Address(V, getContext().getTypeAlignInChars(pointeeTy));
llvm::Value *incomingErrorValue = Builder.CreateLoad(arg);
Builder.CreateStore(incomingErrorValue, temp);
V = temp.getPointer();
// Push a cleanup to copy the value back at the end of the function.
// The convention does not guarantee that the value will be written
// back if the function exits with an unwind exception.
EHStack.pushCleanup<CopyBackSwiftError>(NormalCleanup, temp, arg);
}
// Ensure the argument is the correct type.
if (V->getType() != ArgI.getCoerceToType())
V = Builder.CreateBitCast(V, ArgI.getCoerceToType());
if (isPromoted)
V = emitArgumentDemotion(*this, Arg, V);
// Because of merging of function types from multiple decls it is
// possible for the type of an argument to not match the corresponding
// type in the function type. Since we are codegening the callee
// in here, add a cast to the argument type.
llvm::Type *LTy = ConvertType(Arg->getType());
if (V->getType() != LTy)
V = Builder.CreateBitCast(V, LTy);
ArgVals.push_back(ParamValue::forDirect(V));
break;
}
Address Alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg),
Arg->getName());
// Pointer to store into.
Address Ptr = emitAddressAtOffset(*this, Alloca, ArgI);
// Fast-isel and the optimizer generally like scalar values better than
// FCAs, so we flatten them if this is safe to do for this argument.
llvm::StructType *STy = dyn_cast<llvm::StructType>(ArgI.getCoerceToType());
if (ArgI.isDirect() && ArgI.getCanBeFlattened() && STy &&
STy->getNumElements() > 1) {
uint64_t SrcSize = CGM.getDataLayout().getTypeAllocSize(STy);
llvm::Type *DstTy = Ptr.getElementType();
uint64_t DstSize = CGM.getDataLayout().getTypeAllocSize(DstTy);
Address AddrToStoreInto = Address::invalid();
if (SrcSize <= DstSize) {
AddrToStoreInto = Builder.CreateElementBitCast(Ptr, STy);
} else {
AddrToStoreInto =
CreateTempAlloca(STy, Alloca.getAlignment(), "coerce");
}
assert(STy->getNumElements() == NumIRArgs);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
auto AI = 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);
}
} 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, Ptr, /*DstIsVolatile=*/false, *this);
}
// Match to what EmitParmDecl is expecting for this type.
if (CodeGenFunction::hasScalarEvaluationKind(Ty)) {
llvm::Value *V =
EmitLoadOfScalar(Alloca, false, Ty, Arg->getBeginLoc());
if (isPromoted)
V = emitArgumentDemotion(*this, Arg, V);
ArgVals.push_back(ParamValue::forDirect(V));
} else {
ArgVals.push_back(ParamValue::forIndirect(Alloca));
}
break;
}
case ABIArgInfo::CoerceAndExpand: {
// Reconstruct into a temporary.
Address alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg));
ArgVals.push_back(ParamValue::forIndirect(alloca));
auto coercionType = ArgI.getCoerceAndExpandType();
alloca = Builder.CreateElementBitCast(alloca, coercionType);
unsigned argIndex = FirstIRArg;
for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) {
llvm::Type *eltType = coercionType->getElementType(i);
if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType))
continue;
auto eltAddr = Builder.CreateStructGEP(alloca, i);
auto elt = Fn->getArg(argIndex++);
Builder.CreateStore(elt, eltAddr);
}
assert(argIndex == FirstIRArg + NumIRArgs);
break;
}
case ABIArgInfo::Expand: {
// If this structure was expanded into multiple arguments then
// we need to create a temporary and reconstruct it from the
// arguments.
Address Alloca = CreateMemTemp(Ty, getContext().getDeclAlign(Arg));
LValue LV = MakeAddrLValue(Alloca, Ty);
ArgVals.push_back(ParamValue::forIndirect(Alloca));
auto FnArgIter = 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::Ignore:
assert(NumIRArgs == 0);
// Initialize the local variable appropriately.
if (!hasScalarEvaluationKind(Ty)) {
ArgVals.push_back(ParamValue::forIndirect(CreateMemTemp(Ty)));
} else {
llvm::Value *U = llvm::UndefValue::get(ConvertType(Arg->getType()));
ArgVals.push_back(ParamValue::forDirect(U));
}
break;
}
}
if (getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) {
for (int I = Args.size() - 1; I >= 0; --I)
EmitParmDecl(*Args[I], ArgVals[I], I + 1);
} else {
for (unsigned I = 0, E = Args.size(); I != E; ++I)
EmitParmDecl(*Args[I], ArgVals[I], I + 1);
}
}
static void eraseUnusedBitCasts(llvm::Instruction *insn) {
while (insn->use_empty()) {
llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(insn);
if (!bitcast) return;
// This is "safe" because we would have used a ConstantExpr otherwise.
insn = cast<llvm::Instruction>(bitcast->getOperand(0));
bitcast->eraseFromParent();
}
}
/// Try to emit a fused autorelease of a return result.
static llvm::Value *tryEmitFusedAutoreleaseOfResult(CodeGenFunction &CGF,
llvm::Value *result) {
// We must be immediately followed the cast.
llvm::BasicBlock *BB = CGF.Builder.GetInsertBlock();
if (BB->empty()) return nullptr;
if (&BB->back() != result) return nullptr;
llvm::Type *resultType = result->getType();
// result is in a BasicBlock and is therefore an Instruction.
llvm::Instruction *generator = cast<llvm::Instruction>(result);
SmallVector<llvm::Instruction *, 4> InstsToKill;
// Look for:
// %generator = bitcast %type1* %generator2 to %type2*
while (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(generator)) {
// We would have emitted this as a constant if the operand weren't
// an Instruction.
generator = cast<llvm::Instruction>(bitcast->getOperand(0));
// Require the generator to be immediately followed by the cast.
if (generator->getNextNode() != bitcast)
return nullptr;
InstsToKill.push_back(bitcast);
}
// Look for:
// %generator = call i8* @objc_retain(i8* %originalResult)
// or
// %generator = call i8* @objc_retainAutoreleasedReturnValue(i8* %originalResult)
llvm::CallInst *call = dyn_cast<llvm::CallInst>(generator);
if (!call) return nullptr;
bool doRetainAutorelease;
if (call->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.
llvm::CallInst *retainCall =
dyn_cast<llvm::CallInst>(result->stripPointerCasts());
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).getPointer())
return nullptr;
// Okay! Burn it all down. This relies for correctness on the
// assumption that the retain is emitted as part of the return and
// that thereafter everything is used "linearly".
llvm::Type *resultType = result->getType();
eraseUnusedBitCasts(cast<llvm::Instruction>(result));
assert(retainCall->use_empty());
retainCall->eraseFromParent();
eraseUnusedBitCasts(cast<llvm::Instruction>(retainedValue));
return CGF.Builder.CreateBitCast(load, resultType);
}
/// Emit an ARC autorelease of the result of a function.
///
/// \return the value to actually return from the function
static llvm::Value *emitAutoreleaseOfResult(CodeGenFunction &CGF,
llvm::Value *result) {
// If we're returning 'self', kill the initial retain. This is a
// heuristic attempt to "encourage correctness" in the really unfortunate
// case where we have a return of self during a dealloc and we desperately
// need to avoid the possible autorelease.
if (llvm::Value *self = tryRemoveRetainOfSelf(CGF, result))
return self;
// At -O0, try to emit a fused retain/autorelease.
if (CGF.shouldUseFusedARCCalls())
if (llvm::Value *fused = tryEmitFusedAutoreleaseOfResult(CGF, result))
return fused;
return CGF.EmitARCAutoreleaseReturnValue(result);
}
/// Heuristically search for a dominating store to the return-value slot.
static llvm::StoreInst *findDominatingStoreToReturnValue(CodeGenFunction &CGF) {
// Check if a User is a store which pointerOperand is the ReturnValue.
// We are looking for stores to the ReturnValue, not for stores of the
// ReturnValue to some other location.
auto GetStoreIfValid = [&CGF](llvm::User *U) -> llvm::StoreInst * {
auto *SI = dyn_cast<llvm::StoreInst>(U);
if (!SI || SI->getPointerOperand() != CGF.ReturnValue.getPointer())
return nullptr;
// These aren't actually possible for non-coerced returns, and we
// only care about non-coerced returns on this code path.
assert(!SI->isAtomic() && !SI->isVolatile());
return SI;
};
// If there are multiple uses of the return-value slot, just check
// for something immediately preceding the IP. Sometimes this can
// happen with how we generate implicit-returns; it can also happen
// with noreturn cleanups.
if (!CGF.ReturnValue.getPointer()->hasOneUse()) {
llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
if (IP->empty()) return nullptr;
llvm::Instruction *I = &IP->back();
// Skip lifetime markers
for (llvm::BasicBlock::reverse_iterator II = IP->rbegin(),
IE = IP->rend();
II != IE; ++II) {
if (llvm::IntrinsicInst *Intrinsic =
dyn_cast<llvm::IntrinsicInst>(&*II)) {
if (Intrinsic->getIntrinsicID() == llvm::Intrinsic::lifetime_end) {
const llvm::Value *CastAddr = Intrinsic->getArgOperand(1);
++II;
if (II == IE)
break;
if (isa<llvm::BitCastInst>(&*II) && (CastAddr == &*II))
continue;
}
}
I = &*II;
break;
}
return GetStoreIfValid(I);
}
llvm::StoreInst *store =
GetStoreIfValid(CGF.ReturnValue.getPointer()->user_back());
if (!store) return nullptr;
// Now do a first-and-dirty dominance check: just walk up the
// single-predecessors chain from the current insertion point.
llvm::BasicBlock *StoreBB = store->getParent();
llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
while (IP != StoreBB) {
if (!(IP = IP->getSinglePredecessor()))
return nullptr;
}
// Okay, the store's basic block dominates the insertion point; we
// can do our thing.
return store;
}
// 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(Context) ||
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->getAs<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->getAs<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->getAs<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::UndefValue::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) {
if (FI.isNoReturn()) {
// Noreturn functions don't return.
EmitUnreachable(EndLoc);
return;
}
if (CurCodeDecl && CurCodeDecl->hasAttr<NakedAttr>()) {
// Naked functions don't have epilogues.
Builder.CreateUnreachable();
return;
}
// Functions with no result always return void.
if (!ReturnValue.isValid()) {
Builder.CreateRetVoid();
return;
}
llvm::DebugLoc RetDbgLoc;
llvm::Value *RV = nullptr;
QualType RetTy = FI.getReturnType();
const ABIArgInfo &RetAI = FI.getReturnInfo();
switch (RetAI.getKind()) {
case ABIArgInfo::InAlloca:
// Aggregrates get evaluated directly into the destination. Sometimes we
// need to return the sret value in a register, though.
assert(hasAggregateEvaluationKind(RetTy));
if (RetAI.getInAllocaSRet()) {
llvm::Function::arg_iterator EI = CurFn->arg_end();
--EI;
llvm::Value *ArgStruct = &*EI;
llvm::Value *SRet = Builder.CreateStructGEP(
nullptr, ArgStruct, RetAI.getInAllocaFieldIndex());
RV = Builder.CreateAlignedLoad(SRet, getPointerAlign(), "sret");
}
break;
case ABIArgInfo::Indirect: {
auto AI = CurFn->arg_begin();
if (RetAI.isSRetAfterThis())
++AI;
switch (getEvaluationKind(RetTy)) {
case TEK_Complex: {
ComplexPairTy RT =
EmitLoadOfComplex(MakeAddrLValue(ReturnValue, RetTy), EndLoc);
EmitStoreOfComplex(RT, MakeNaturalAlignAddrLValue(&*AI, RetTy),
/*isInit*/ true);
break;
}
case TEK_Aggregate:
// Do nothing; aggregrates get evaluated directly into the destination.
break;
case TEK_Scalar:
EmitStoreOfScalar(Builder.CreateLoad(ReturnValue),
MakeNaturalAlignAddrLValue(&*AI, RetTy),
/*isInit*/ true);
break;
}
break;
}
case ABIArgInfo::Extend:
case ABIArgInfo::Direct:
if (RetAI.getCoerceToType() == ConvertType(RetTy) &&
RetAI.getDirectOffset() == 0) {
// The internal return value temp always will have pointer-to-return-type
// type, just do a load.
// If there is a dominating store to ReturnValue, we can elide
// the load, zap the store, and usually zap the alloca.
if (llvm::StoreInst *SI =
findDominatingStoreToReturnValue(*this)) {
// Reuse the debug location from the store unless there is
// cleanup code to be emitted between the store and return
// instruction.
if (EmitRetDbgLoc && !AutoreleaseResult)
RetDbgLoc = SI->getDebugLoc();
// Get the stored value and nuke the now-dead store.
RV = SI->getValueOperand();
SI->eraseFromParent();
// Otherwise, we have to do a simple load.
} else {
RV = Builder.CreateLoad(ReturnValue);
}
} else {
// If the value is offset in memory, apply the offset now.
Address V = emitAddressAtOffset(*this, ReturnValue, RetAI);
RV = CreateCoercedLoad(V, RetAI.getCoerceToType(), *this);
}
// In ARC, end functions that return a retainable type with a call
// to objc_autoreleaseReturnValue.
if (AutoreleaseResult) {
#ifndef NDEBUG
// Type::isObjCRetainabletype has to be called on a QualType that hasn't
// been stripped of the typedefs, so we cannot use RetTy here. Get the
// original return type of FunctionDecl, CurCodeDecl, and BlockDecl from
// CurCodeDecl or BlockInfo.
QualType RT;
if (auto *FD = dyn_cast<FunctionDecl>(CurCodeDecl))
RT = FD->getReturnType();
else if (auto *MD = dyn_cast<ObjCMethodDecl>(CurCodeDecl))
RT = MD->getReturnType();
else if (isa<BlockDecl>(CurCodeDecl))
RT = BlockInfo->BlockExpression->getFunctionType()->getReturnType();
else
llvm_unreachable("Unexpected function/method type");
assert(getLangOpts().ObjCAutoRefCount &&
!FI.isReturnsRetained() &&
RT->isObjCRetainableType());
#endif
RV = emitAutoreleaseOfResult(*this, RV);
}
break;
case ABIArgInfo::Ignore:
break;
case ABIArgInfo::CoerceAndExpand: {
auto coercionType = RetAI.getCoerceAndExpandType();
// Load all of the coerced elements out into results.
llvm::SmallVector<llvm::Value*, 4> results;
Address addr = Builder.CreateElementBitCast(ReturnValue, coercionType);
for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) {
auto coercedEltType = coercionType->getElementType(i);
if (ABIArgInfo::isPaddingForCoerceAndExpand(coercedEltType))
continue;
auto eltAddr = Builder.CreateStructGEP(addr, i);
auto elt = Builder.CreateLoad(eltAddr);
results.push_back(elt);
}
// If we have one result, it's the single direct result type.
if (results.size() == 1) {
RV = results[0];
// Otherwise, we need to make a first-class aggregate.
} else {
// Construct a return type that lacks padding elements.
llvm::Type *returnType = RetAI.getUnpaddedCoerceAndExpandType();
RV = llvm::UndefValue::get(returnType);
for (unsigned i = 0, e = results.size(); i != e; ++i) {
RV = Builder.CreateInsertValue(RV, results[i], i);
}
}
break;
}
case ABIArgInfo::Expand:
llvm_unreachable("Invalid ABI kind for return argument");
}
llvm::Instruction *Ret;
if (RV) {
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));
}
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;
SanitizerMask CheckKind;
SanitizerHandler Handler;
if (RetNNAttr) {
assert(!requiresReturnValueNullabilityCheck() &&
"Cannot check nullability and the nonnull attribute");
AttrLoc = RetNNAttr->getLocation();
CheckKind = SanitizerKind::ReturnsNonnullAttribute;
Handler = SanitizerHandler::NonnullReturn;
} else {
if (auto *DD = dyn_cast<DeclaratorDecl>(CurCodeDecl))
if (auto *TSI = DD->getTypeSourceInfo())
if (auto FTL = TSI->getTypeLoc().getAsAdjusted<FunctionTypeLoc>())
AttrLoc = FTL.getReturnLoc().findNullabilityLoc();
CheckKind = SanitizerKind::NullabilityReturn;
Handler = SanitizerHandler::NullabilityReturn;
}
SanitizerScope SanScope(this);
// Make sure the "return" source location is valid. If we're checking a
// nullability annotation, make sure the preconditions for the check are met.
llvm::BasicBlock *Check = createBasicBlock("nullcheck");
llvm::BasicBlock *NoCheck = createBasicBlock("no.nullcheck");
llvm::Value *SLocPtr = Builder.CreateLoad(ReturnLocation, "return.sloc.load");
llvm::Value *CanNullCheck = Builder.CreateIsNotNull(SLocPtr);
if (requiresReturnValueNullabilityCheck())
CanNullCheck =
Builder.CreateAnd(CanNullCheck, RetValNullabilityPrecondition);
Builder.CreateCondBr(CanNullCheck, Check, NoCheck);
EmitBlock(Check);
// Now do the null check.
llvm::Value *Cond = Builder.CreateIsNotNull(RV);
llvm::Constant *StaticData[] = {EmitCheckSourceLocation(AttrLoc)};
llvm::Value *DynamicData[] = {SLocPtr};
EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, DynamicData);
EmitBlock(NoCheck);
#ifndef NDEBUG
// The return location should not be used after the check has been emitted.
ReturnLocation = Address::invalid();
#endif
}
static bool isInAllocaArgument(CGCXXABI &ABI, QualType type) {
const CXXRecordDecl *RD = type->getAsCXXRecordDecl();
return RD && ABI.getRecordArgABI(RD) == CGCXXABI::RAA_DirectInMemory;
}
static AggValueSlot createPlaceholderSlot(CodeGenFunction &CGF,
QualType Ty) {
// FIXME: Generate IR in one pass, rather than going back and fixing up these
// placeholders.
llvm::Type *IRTy = CGF.ConvertTypeForMem(Ty);
llvm::Type *IRPtrTy = IRTy->getPointerTo();
llvm::Value *Placeholder = llvm::UndefValue::get(IRPtrTy->getPointerTo());
// FIXME: When we generate this IR in one pass, we shouldn't need
// this win32-specific alignment hack.
CharUnits Align = CharUnits::fromQuantity(4);
Placeholder = CGF.Builder.CreateAlignedLoad(IRPtrTy, Placeholder, Align);
return AggValueSlot::forAddr(Address(Placeholder, Align),
Ty.getQualifiers(),
AggValueSlot::IsNotDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased,
AggValueSlot::DoesNotOverlap);
}
void CodeGenFunction::EmitDelegateCallArg(CallArgList &args,
const VarDecl *param,
SourceLocation loc) {
// StartFunction converted the ABI-lowered parameter(s) into a
// local alloca. We need to turn that into an r-value suitable
// for EmitCall.
Address local = GetAddrOfLocalVar(param);
QualType type = param->getType();
if (isInAllocaArgument(CGM.getCXXABI(), type)) {
CGM.ErrorUnsupported(param, "forwarded non-trivially copyable parameter");
}
// GetAddrOfLocalVar returns a pointer-to-pointer for references,
// but the argument needs to be the original pointer.
if (type->isReferenceType()) {
args.add(RValue::get(Builder.CreateLoad(local)), type);
// In ARC, move out of consumed arguments so that the release cleanup
// entered by StartFunction doesn't cause an over-release. This isn't
// optimal -O0 code generation, but it should get cleaned up when
// optimization is enabled. This also assumes that delegate calls are
// performed exactly once for a set of arguments, but that should be safe.
} else if (getLangOpts().ObjCAutoRefCount &&
param->hasAttr<NSConsumedAttr>() &&
type->isObjCRetainableType()) {
llvm::Value *ptr = Builder.CreateLoad(local);
auto null =
llvm::ConstantPointerNull::get(cast<llvm::PointerType>(ptr->getType()));
Builder.CreateStore(null, local);
args.add(RValue::get(ptr), type);
// For the most part, we just need to load the alloca, except that
// aggregate r-values are actually pointers to temporaries.
} else {
args.add(convertTempToRValue(local, type, loc), type);
}
// Deactivate the cleanup for the callee-destructed param that was pushed.
if (hasAggregateEvaluationKind(type) && !CurFuncIsThunk &&
type->castAs<RecordType>()->getDecl()->isParamDestroyedInCallee() &&
param->needsDestruction(getContext())) {
EHScopeStack::stable_iterator cleanup =
CalleeDestructedParamCleanups.lookup(cast<ParmVarDecl>(param));
assert(cleanup.isValid() &&
"cleanup for callee-destructed param not recorded");
// This unreachable is a temporary marker which will be removed later.
llvm::Instruction *isActive = Builder.CreateUnreachable();
args.addArgCleanupDeactivation(cleanup, isActive);
}
}
static bool isProvablyNull(llvm::Value *addr) {
return isa<llvm::ConstantPointerNull>(addr);
}
/// Emit the actual writing-back of a writeback.
static void emitWriteback(CodeGenFunction &CGF,
const CallArgList::Writeback &writeback) {
const LValue &srcLV = writeback.Source;
Address srcAddr = srcLV.getAddress(CGF);
assert(!isProvablyNull(srcAddr.getPointer()) &&
"shouldn't have writeback for provably null argument");
llvm::BasicBlock *contBB = nullptr;
// If the argument wasn't provably non-null, we need to null check
// before doing the store.
bool provablyNonNull = llvm::isKnownNonZero(srcAddr.getPointer(),
CGF.CGM.getDataLayout());
if (!provablyNonNull) {
llvm::BasicBlock *writebackBB = CGF.createBasicBlock("icr.writeback");
contBB = CGF.createBasicBlock("icr.done");
llvm::Value *isNull =
CGF.Builder.CreateIsNull(srcAddr.getPointer(), "icr.isnull");
CGF.Builder.CreateCondBr(isNull, contBB, writebackBB);
CGF.EmitBlock(writebackBB);
}
// Load the value to writeback.
llvm::Value *value = CGF.Builder.CreateLoad(writeback.Temporary);
// Cast it back, in case we're writing an id to a Foo* or something.
value = CGF.Builder.CreateBitCast(value, srcAddr.getElementType(),
"icr.writeback-cast");
// Perform the writeback.
// If we have a "to use" value, it's something we need to emit a use
// of. This has to be carefully threaded in: if it's done after the
// release it's potentially undefined behavior (and the optimizer
// will ignore it), and if it happens before the retain then the
// optimizer could move the release there.
if (writeback.ToUse) {
assert(srcLV.getObjCLifetime() == Qualifiers::OCL_Strong);
// Retain the new value. No need to block-copy here: the block's
// being passed up the stack.
value = CGF.EmitARCRetainNonBlock(value);
// Emit the intrinsic use here.
CGF.EmitARCIntrinsicUse(writeback.ToUse);
// Load the old value (primitively).
llvm::Value *oldValue = CGF.EmitLoadOfScalar(srcLV, SourceLocation());
// Put the new value in place (primitively).
CGF.EmitStoreOfScalar(value, srcLV, /*init*/ false);
// Release the old value.
CGF.EmitARCRelease(oldValue, srcLV.isARCPreciseLifetime());
// Otherwise, we can just do a normal lvalue store.
} else {
CGF.EmitStoreThroughLValue(RValue::get(value), srcLV);
}
// Jump to the continuation block.
if (!provablyNonNull)
CGF.EmitBlock(contBB);
}
static void emitWritebacks(CodeGenFunction &CGF,
const CallArgList &args) {
for (const auto &I : args.writebacks())
emitWriteback(CGF, I);
}
static void deactivateArgCleanupsBeforeCall(CodeGenFunction &CGF,
const CallArgList &CallArgs) {
ArrayRef<CallArgList::CallArgCleanup> Cleanups =
CallArgs.getCleanupsToDeactivate();
// Iterate in reverse to increase the likelihood of popping the cleanup.
for (const auto &I : llvm::reverse(Cleanups)) {
CGF.DeactivateCleanupBlock(I.Cleanup, I.IsActiveIP);
I.IsActiveIP->eraseFromParent();
}
}
static const Expr *maybeGetUnaryAddrOfOperand(const Expr *E) {
if (const UnaryOperator *uop = dyn_cast<UnaryOperator>(E->IgnoreParens()))
if (uop->getOpcode() == UO_AddrOf)
return uop->getSubExpr();
return nullptr;
}
/// Emit an argument that's being passed call-by-writeback. That is,
/// we are passing the address of an __autoreleased temporary; it
/// might be copy-initialized with the current value of the given
/// address, but it will definitely be copied out of after the call.
static void emitWritebackArg(CodeGenFunction &CGF, CallArgList &args,
const ObjCIndirectCopyRestoreExpr *CRE) {
LValue srcLV;
// Make an optimistic effort to emit the address as an l-value.
// This can fail if the argument expression is more complicated.
if (const Expr *lvExpr = maybeGetUnaryAddrOfOperand(CRE->getSubExpr())) {
srcLV = CGF.EmitLValue(lvExpr);
// Otherwise, just emit it as a scalar.
} else {
Address srcAddr = CGF.EmitPointerWithAlignment(CRE->getSubExpr());
QualType srcAddrType =
CRE->getSubExpr()->getType()->castAs<PointerType>()->getPointeeType();
srcLV = CGF.MakeAddrLValue(srcAddr, srcAddrType);
}
Address srcAddr = srcLV.getAddress(CGF);
// The dest and src types don't necessarily match in LLVM terms
// because of the crazy ObjC compatibility rules.
llvm::PointerType *destType =
cast<llvm::PointerType>(CGF.ConvertType(CRE->getType()));
// If the address is a constant null, just pass the appropriate null.
if (isProvablyNull(srcAddr.getPointer())) {
args.add(RValue::get(llvm::ConstantPointerNull::get(destType)),
CRE->getType());
return;
}
// Create the temporary.
Address temp = CGF.CreateTempAlloca(destType->getElementType(),
CGF.getPointerAlign(),
"icr.temp");
// Loading an l-value can introduce a cleanup if the l-value is __weak,
// and that cleanup will be conditional if we can't prove that the l-value
// isn't null, so we need to register a dominating point so that the cleanups
// system will make valid IR.
CodeGenFunction::ConditionalEvaluation condEval(CGF);
// Zero-initialize it if we're not doing a copy-initialization.
bool shouldCopy = CRE->shouldCopy();
if (!shouldCopy) {
llvm::Value *null =
llvm::ConstantPointerNull::get(
cast<llvm::PointerType>(destType->getElementType()));
CGF.Builder.CreateStore(null, temp);
}
llvm::BasicBlock *contBB = nullptr;
llvm::BasicBlock *originBB = nullptr;
// If the address is *not* known to be non-null, we need to switch.
llvm::Value *finalArgument;
bool provablyNonNull = llvm::isKnownNonZero(srcAddr.getPointer(),
CGF.CGM.getDataLayout());
if (provablyNonNull) {
finalArgument = temp.getPointer();
} else {
llvm::Value *isNull =
CGF.Builder.CreateIsNull(srcAddr.getPointer(), "icr.isnull");
finalArgument = CGF.Builder.CreateSelect(isNull,
llvm::ConstantPointerNull::get(destType),
temp.getPointer(), "icr.argument");
// If we need to copy, then the load has to be conditional, which
// means we need control flow.
if (shouldCopy) {
originBB = CGF.Builder.GetInsertBlock();
contBB = CGF.createBasicBlock("icr.cont");
llvm::BasicBlock *copyBB = CGF.createBasicBlock("icr.copy");
CGF.Builder.CreateCondBr(isNull, contBB, copyBB);
CGF.EmitBlock(copyBB);
condEval.begin(CGF);
}
}
llvm::Value *valueToUse = nullptr;
// Perform a copy if necessary.
if (shouldCopy) {
RValue srcRV = CGF.EmitLoadOfLValue(srcLV, SourceLocation());
assert(srcRV.isScalar());
llvm::Value *src = srcRV.getScalarVal();
src = CGF.Builder.CreateBitCast(src, destType->getElementType(),
"icr.cast");
// Use an ordinary store, not a store-to-lvalue.
CGF.Builder.CreateStore(src, temp);
// If optimization is enabled, and the value was held in a
// __strong variable, we need to tell the optimizer that this
// value has to stay alive until we're doing the store back.
// This is because the temporary is effectively unretained,
// and so otherwise we can violate the high-level semantics.
if (CGF.CGM.getCodeGenOpts().OptimizationLevel != 0 &&
srcLV.getObjCLifetime() == Qualifiers::OCL_Strong) {
valueToUse = src;
}
}
// Finish the control flow if we needed it.
if (shouldCopy && !provablyNonNull) {
llvm::BasicBlock *copyBB = CGF.Builder.GetInsertBlock();
CGF.EmitBlock(contBB);
// Make a phi for the value to intrinsically use.
if (valueToUse) {
llvm::PHINode *phiToUse = CGF.Builder.CreatePHI(valueToUse->getType(), 2,
"icr.to-use");
phiToUse->addIncoming(valueToUse, copyBB);
phiToUse->addIncoming(llvm::UndefValue::get(valueToUse->getType()),
originBB);
valueToUse = phiToUse;
}
condEval.end(CGF);
}
args.addWriteback(srcLV, temp, valueToUse);
args.add(RValue::get(finalArgument), CRE->getType());
}
void CallArgList::allocateArgumentMemory(CodeGenFunction &CGF) {
assert(!StackBase);
// Save the stack.
llvm::Function *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stacksave);
StackBase = CGF.Builder.CreateCall(F, {}, "inalloca.save");
}
void CallArgList::freeArgumentMemory(CodeGenFunction &CGF) const {
if (StackBase) {
// Restore the stack after the call.
llvm::Function *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
CGF.Builder.CreateCall(F, StackBase);
}
}
void CodeGenFunction::EmitNonNullArgCheck(RValue RV, QualType ArgType,
SourceLocation ArgLoc,
AbstractCallee AC,
unsigned ParmNum) {
if (!AC.getDecl() || !(SanOpts.has(SanitizerKind::NonnullAttribute) ||
SanOpts.has(SanitizerKind::NullabilityArg)))
return;
// The param decl may be missing in a variadic function.
auto PVD = ParmNum < AC.getNumParams() ? AC.getParamDecl(ParmNum) : nullptr;
unsigned ArgNo = PVD ? PVD->getFunctionScopeIndex() : ParmNum;
// Prefer the nonnull attribute if it's present.
const NonNullAttr *NNAttr = nullptr;
if (SanOpts.has(SanitizerKind::NonnullAttribute))
NNAttr = getNonNullAttr(AC.getDecl(), PVD, ArgType, ArgNo);
bool CanCheckNullability = false;
if (SanOpts.has(SanitizerKind::NullabilityArg) && !NNAttr && PVD) {
auto Nullability = PVD->getType()->getNullability(getContext());
CanCheckNullability = Nullability &&
*Nullability == NullabilityKind::NonNull &&
PVD->getTypeSourceInfo();
}
if (!NNAttr && !CanCheckNullability)
return;
SourceLocation AttrLoc;
SanitizerMask CheckKind;
SanitizerHandler Handler;
if (NNAttr) {
AttrLoc = NNAttr->getLocation();
CheckKind = SanitizerKind::NonnullAttribute;
Handler = SanitizerHandler::NonnullArg;
} else {
AttrLoc = PVD->getTypeSourceInfo()->getTypeLoc().findNullabilityLoc();
CheckKind = SanitizerKind::NullabilityArg;
Handler = SanitizerHandler::NullabilityArg;
}
SanitizerScope SanScope(this);
assert(RV.isScalar());
llvm::Value *V = RV.getScalarVal();
llvm::Value *Cond =
Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType()));
llvm::Constant *StaticData[] = {
EmitCheckSourceLocation(ArgLoc), EmitCheckSourceLocation(AttrLoc),
llvm::ConstantInt::get(Int32Ty, ArgNo + 1),
};
EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, None);
}
void CodeGenFunction::EmitCallArgs(
CallArgList &Args, ArrayRef<QualType> ArgTypes,
llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
AbstractCallee AC, unsigned ParamsToSkip, EvaluationOrder Order) {
assert((int)ArgTypes.size() == (ArgRange.end() - ArgRange.begin()));
// We *have* to evaluate arguments from right to left in the MS C++ ABI,
// because arguments are destroyed left to right in the callee. As a special
// case, there are certain language constructs that require left-to-right
// evaluation, and in those cases we consider the evaluation order requirement
// to trump the "destruction order is reverse construction order" guarantee.
bool LeftToRight =
CGM.getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()
? Order == EvaluationOrder::ForceLeftToRight
: Order != EvaluationOrder::ForceRightToLeft;
auto MaybeEmitImplicitObjectSize = [&](unsigned I, const Expr *Arg,
RValue EmittedArg) {
if (!AC.hasFunctionDecl() || I >= AC.getNumParams())
return;
auto *PS = AC.getParamDecl(I)->getAttr<PassObjectSizeAttr>();
if (PS == nullptr)
return;
const auto &Context = getContext();
auto SizeTy = Context.getSizeType();
auto T = Builder.getIntNTy(Context.getTypeSize(SizeTy));
assert(EmittedArg.getScalarVal() && "We emitted nothing for the arg?");
llvm::Value *V = evaluateOrEmitBuiltinObjectSize(Arg, PS->getType(), T,
EmittedArg.getScalarVal(),
PS->isDynamic());
Args.add(RValue::get(V), SizeTy);
// If we're emitting args in reverse, be sure to do so with
// pass_object_size, as well.
if (!LeftToRight)
std::swap(Args.back(), *(&Args.back() - 1));
};
// Insert a stack save if we're going to need any inalloca args.
bool HasInAllocaArgs = false;
if (CGM.getTarget().getCXXABI().isMicrosoft()) {
for (ArrayRef<QualType>::iterator I = ArgTypes.begin(), E = ArgTypes.end();
I != E && !HasInAllocaArgs; ++I)
HasInAllocaArgs = isInAllocaArgument(CGM.getCXXABI(), *I);
if (HasInAllocaArgs) {
assert(getTarget().getTriple().getArch() == llvm::Triple::x86);
Args.allocateArgumentMemory(*this);
}
}
// Evaluate each argument in the appropriate order.
size_t CallArgsStart = Args.size();
for (unsigned I = 0, E = ArgTypes.size(); I != E; ++I) {
unsigned Idx = LeftToRight ? I : E - I - 1;
CallExpr::const_arg_iterator Arg = ArgRange.begin() + Idx;
unsigned InitialArgSize = Args.size();
// If *Arg is an ObjCIndirectCopyRestoreExpr, check that either the types of
// the argument and parameter match or the objc method is parameterized.
assert((!isa<ObjCIndirectCopyRestoreExpr>(*Arg) ||
getContext().hasSameUnqualifiedType((*Arg)->getType(),
ArgTypes[Idx]) ||
(isa<ObjCMethodDecl>(AC.getDecl()) &&
isObjCMethodWithTypeParams(cast<ObjCMethodDecl>(AC.getDecl())))) &&
"Argument and parameter types don't match");
EmitCallArg(Args, *Arg, ArgTypes[Idx]);
// In particular, we depend on it being the last arg in Args, and the
// objectsize bits depend on there only being one arg if !LeftToRight.
assert(InitialArgSize + 1 == Args.size() &&
"The code below depends on only adding one arg per EmitCallArg");
(void)InitialArgSize;
// Since pointer argument are never emitted as LValue, it is safe to emit
// non-null argument check for r-value only.
if (!Args.back().hasLValue()) {
RValue RVArg = Args.back().getKnownRValue();
EmitNonNullArgCheck(RVArg, ArgTypes[Idx], (*Arg)->getExprLoc(), AC,
ParamsToSkip + Idx);
// @llvm.objectsize should never have side-effects and shouldn't need
// destruction/cleanups, so we can safely "emit" it after its arg,
// regardless of right-to-leftness
MaybeEmitImplicitObjectSize(Idx, *Arg, RVArg);
}
}
if (!LeftToRight) {
// Un-reverse the arguments we just evaluated so they match up with the LLVM
// IR function.
std::reverse(Args.begin() + CallArgsStart, Args.end());
}
}
namespace {
struct DestroyUnpassedArg final : EHScopeStack::Cleanup {
DestroyUnpassedArg(Address Addr, QualType Ty)
: Addr(Addr), Ty(Ty) {}
Address Addr;
QualType Ty;
void Emit(CodeGenFunction &CGF, Flags flags) override {
QualType::DestructionKind DtorKind = Ty.isDestructedType();
if (DtorKind == QualType::DK_cxx_destructor) {
const CXXDestructorDecl *Dtor = Ty->getAsCXXRecordDecl()->getDestructor();
assert(!Dtor->isTrivial());
CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete, /*for vbase*/ false,
/*Delegating=*/false, Addr, Ty);
} else {
CGF.callCStructDestructor(CGF.MakeAddrLValue(Addr, Ty));
}
}
};
struct DisableDebugLocationUpdates {
CodeGenFunction &CGF;
bool disabledDebugInfo;
DisableDebugLocationUpdates(CodeGenFunction &CGF, const Expr *E) : CGF(CGF) {
if ((disabledDebugInfo = isa<CXXDefaultArgExpr>(E) && CGF.getDebugInfo()))
CGF.disableDebugInfo();
}
~DisableDebugLocationUpdates() {
if (disabledDebugInfo)
CGF.enableDebugInfo();
}
};
} // end anonymous namespace
RValue CallArg::getRValue(CodeGenFunction &CGF) const {
if (!HasLV)
return RV;
LValue Copy = CGF.MakeAddrLValue(CGF.CreateMemTemp(Ty), Ty);
CGF.EmitAggregateCopy(Copy, LV, Ty, AggValueSlot::DoesNotOverlap,
LV.isVolatile());
IsUsed = true;
return RValue::getAggregate(Copy.getAddress(CGF));
}
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(CGF) : RV.getAggregateAddress();
LValue SrcLV = CGF.MakeAddrLValue(Addr, Ty);
// We assume that call args are never copied into subobjects.
CGF.EmitAggregateCopy(Dst, SrcLV, Ty, AggValueSlot::DoesNotOverlap,
HasLV ? LV.isVolatileQualified()
: RV.isVolatileQualified());
}
IsUsed = true;
}
void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E,
QualType type) {
DisableDebugLocationUpdates Dis(*this, E);
if (const ObjCIndirectCopyRestoreExpr *CRE
= dyn_cast<ObjCIndirectCopyRestoreExpr>(E)) {
assert(getLangOpts().ObjCAutoRefCount);
return emitWritebackArg(*this, args, CRE);
}
assert(type->isReferenceType() == E->isGLValue() &&
"reference binding to unmaterialized r-value!");
if (E->isGLValue()) {
assert(E->getObjectKind() == OK_Ordinary);
return args.add(EmitReferenceBindingToExpr(E), type);
}
bool HasAggregateEvalKind = hasAggregateEvaluationKind(type);
// In the Microsoft C++ ABI, aggregate arguments are destructed by the callee.
// However, we still have to push an EH-only cleanup in case we unwind before
// we make it to the call.
if (HasAggregateEvalKind &&
type->castAs<RecordType>()->getDecl()->isParamDestroyedInCallee()) {
// If we're using inalloca, use the argument memory. Otherwise, use a
// temporary.
AggValueSlot Slot;
if (args.isUsingInAlloca())
Slot = createPlaceholderSlot(*this, type);
else
Slot = CreateAggTemp(type, "agg.tmp");
bool DestroyedInCallee = true, NeedsEHCleanup = true;
if (const auto *RD = type->getAsCXXRecordDecl())
DestroyedInCallee = RD->hasNonTrivialDestructor();
else
NeedsEHCleanup = needsEHCleanup(type.isDestructedType());
if (DestroyedInCallee)
Slot.setExternallyDestructed();
EmitAggExpr(E, Slot);
RValue RV = Slot.asRValue();
args.add(RV, type);
if (DestroyedInCallee && NeedsEHCleanup) {
// Create a no-op GEP between the placeholder and the cleanup so we can
// RAUW it successfully. It also serves as a marker of the first
// instruction where the cleanup is active.
pushFullExprCleanup<DestroyUnpassedArg>(EHCleanup, Slot.getAddress(),
type);
// This unreachable is a temporary marker which will be removed later.
llvm::Instruction *IsActive = Builder.CreateUnreachable();
args.addArgCleanupDeactivation(EHStack.getInnermostEHScope(), IsActive);
}
return;
}
if (HasAggregateEvalKind && isa<ImplicitCastExpr>(E) &&
cast<CastExpr>(E)->getCastKind() == CK_LValueToRValue) {
LValue L = EmitLValue(cast<CastExpr>(E)->getSubExpr());
assert(L.isSimple());
args.addUncopiedAggregate(L, type);
return;
}
args.add(EmitAnyExprToTemp(E), type);
}
QualType CodeGenFunction::getVarArgType(const Expr *Arg) {
// System headers on Windows define NULL to 0 instead of 0LL on Win64. MSVC
// implicitly widens null pointer constants that are arguments to varargs
// functions to pointer-sized ints.
if (!getTarget().getTriple().isOSWindows())
return Arg->getType();
if (Arg->getType()->isIntegerType() &&
getContext().getTypeSize(Arg->getType()) <
getContext().getTargetInfo().getPointerWidth(0) &&
Arg->isNullPointerConstant(getContext(),
Expr::NPC_ValueDependentIsNotNull)) {
return getContext().getIntPtrType();
}
return Arg->getType();
}
// In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
// optimizer it can aggressively ignore unwind edges.
void
CodeGenFunction::AddObjCARCExceptionMetadata(llvm::Instruction *Inst) {
if (CGM.getCodeGenOpts().OptimizationLevel != 0 &&
!CGM.getCodeGenOpts().ObjCAutoRefCountExceptions)
Inst->setMetadata("clang.arc.no_objc_arc_exceptions",
CGM.getNoObjCARCExceptionsMetadata());
}
/// Emits a call to the given no-arguments nounwind runtime function.
llvm::CallInst *
CodeGenFunction::EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
const llvm::Twine &name) {
return EmitNounwindRuntimeCall(callee, None, name);
}
/// Emits a call to the given nounwind runtime function.
llvm::CallInst *
CodeGenFunction::EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
ArrayRef<llvm::Value *> args,
const llvm::Twine &name) {
llvm::CallInst *call = EmitRuntimeCall(callee, args, name);
call->setDoesNotThrow();
return call;
}
/// Emits a simple call (never an invoke) to the given no-arguments
/// runtime function.
llvm::CallInst *CodeGenFunction::EmitRuntimeCall(llvm::FunctionCallee callee,
const llvm::Twine &name) {
return EmitRuntimeCall(callee, None, name);
}
// Calls which may throw must have operand bundles indicating which funclet
// they are nested within.
SmallVector<llvm::OperandBundleDef, 1>
CodeGenFunction::getBundlesForFunclet(llvm::Value *Callee) {
SmallVector<llvm::OperandBundleDef, 1> BundleList;
// There is no need for a funclet operand bundle if we aren't inside a
// funclet.
if (!CurrentFuncletPad)
return BundleList;
// Skip intrinsics which cannot throw.
auto *CalleeFn = dyn_cast<llvm::Function>(Callee->stripPointerCasts());
if (CalleeFn && CalleeFn->isIntrinsic() && CalleeFn->doesNotThrow())
return BundleList;
BundleList.emplace_back("funclet", CurrentFuncletPad);
return BundleList;
}
/// Emits a simple call (never an invoke) to the given runtime function.
llvm::CallInst *CodeGenFunction::EmitRuntimeCall(llvm::FunctionCallee callee,
ArrayRef<llvm::Value *> args,
const llvm::Twine &name) {
llvm::CallInst *call = Builder.CreateCall(
callee, args, getBundlesForFunclet(callee.getCallee()), name);
call->setCallingConv(getRuntimeCC());
return call;
}
/// Emits a call or invoke to the given noreturn runtime function.
void CodeGenFunction::EmitNoreturnRuntimeCallOrInvoke(
llvm::FunctionCallee callee, ArrayRef<llvm::Value *> args) {
SmallVector<llvm::OperandBundleDef, 1> BundleList =
getBundlesForFunclet(callee.getCallee());
if (getInvokeDest()) {
llvm::InvokeInst *invoke =
Builder.CreateInvoke(callee,
getUnreachableBlock(),
getInvokeDest(),
args,
BundleList);
invoke->setDoesNotReturn();
invoke->setCallingConv(getRuntimeCC());
} else {
llvm::CallInst *call = Builder.CreateCall(callee, args, BundleList);
call->setDoesNotReturn();
call->setCallingConv(getRuntimeCC());
Builder.CreateUnreachable();
}
}
/// Emits a call or invoke instruction to the given nullary runtime function.
llvm::CallBase *
CodeGenFunction::EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
const Twine &name) {
return EmitRuntimeCallOrInvoke(callee, None, name);
}
/// Emits a call or invoke instruction to the given runtime function.
llvm::CallBase *
CodeGenFunction::EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
ArrayRef<llvm::Value *> args,
const Twine &name) {
llvm::CallBase *call = EmitCallOrInvoke(callee, args, name);
call->setCallingConv(getRuntimeCC());
return call;
}
/// Emits a call or invoke instruction to the given function, depending
/// on the current state of the EH stack.
llvm::CallBase *CodeGenFunction::EmitCallOrInvoke(llvm::FunctionCallee Callee,
ArrayRef<llvm::Value *> Args,
const Twine &Name) {
llvm::BasicBlock *InvokeDest = getInvokeDest();
SmallVector<llvm::OperandBundleDef, 1> BundleList =
getBundlesForFunclet(Callee.getCallee());
llvm::CallBase *Inst;
if (!InvokeDest)
Inst = Builder.CreateCall(Callee, Args, BundleList, Name);
else {
llvm::BasicBlock *ContBB = createBasicBlock("invoke.cont");
Inst = Builder.CreateInvoke(Callee, ContBB, InvokeDest, Args, BundleList,
Name);
EmitBlock(ContBB);
}
// In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
// optimizer it can aggressively ignore unwind edges.
if (CGM.getLangOpts().ObjCAutoRefCount)
AddObjCARCExceptionMetadata(Inst);
return Inst;
}
void CodeGenFunction::deferPlaceholderReplacement(llvm::Instruction *Old,
llvm::Value *New) {
DeferredReplacements.push_back(std::make_pair(Old, New));
}
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.
LLVM_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
.removeAttribute(Ctx, llvm::AttributeList::ReturnIndex,
llvm::Attribute::AttrKind::Alignment)
.addAttribute(Ctx, llvm::AttributeList::ReturnIndex, 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.
LLVM_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
RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
const CGCallee &Callee,
ReturnValueSlot ReturnValue,
const CallArgList &CallArgs,
llvm::CallBase **callOrInvoke,
SourceLocation Loc) {
// FIXME: We no longer need the types from CallArgs; lift up and simplify.
assert(Callee.isOrdinary() || Callee.isVirtual());
// Handle struct-return functions by passing a pointer to the
// location that we would like to return into.
QualType RetTy = CallInfo.getReturnType();
const ABIArgInfo &RetAI = CallInfo.getReturnInfo();
llvm::FunctionType *IRFuncTy = getTypes().GetFunctionType(CallInfo);
const Decl *TargetDecl = Callee.getAbstractInfo().getCalleeDecl().getDecl();
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
// We can only guarantee that a function is called from the correct
// context/function based on the appropriate target attributes,
// so only check in the case where we have both always_inline and target
// since otherwise we could be making a conditional call after a check for
// the proper cpu features (and it won't cause code generation issues due to
// function based code generation).
if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
TargetDecl->hasAttr<TargetAttr>())
checkTargetFeatures(Loc, FD);
// Some architectures (such as x86-64) have the ABI changed based on
// attribute-target/features. Give them a chance to diagnose.
CGM.getTargetCodeGenInfo().checkFunctionCallABI(
CGM, Loc, dyn_cast_or_null<FunctionDecl>(CurCodeDecl), FD, CallArgs);
}
#ifndef NDEBUG
if (!(CallInfo.isVariadic() && CallInfo.getArgStruct())) {
// For an inalloca varargs function, we don't expect CallInfo to match the
// function pointer's type, because the inalloca struct a will have extra
// fields in it for the varargs parameters. Code later in this function
// bitcasts the function pointer to the type derived from CallInfo.
//
// In other cases, we assert that the types match up (until pointers stop
// having pointee types).
llvm::Type *TypeFromVal;
if (Callee.isVirtual())
TypeFromVal = Callee.getVirtualFunctionType();
else
TypeFromVal =
Callee.getFunctionPointer()->getType()->getPointerElementType();
assert(IRFuncTy == TypeFromVal);
}
#endif
// 1. Set up the arguments.
// If we're using inalloca, insert the allocation after the stack save.
// FIXME: Do this earlier rather than hacking it in here!
Address ArgMemory = Address::invalid();
if (llvm::StructType *ArgStruct = CallInfo.getArgStruct()) {
const llvm::DataLayout &DL = CGM.getDataLayout();
llvm::Instruction *IP = CallArgs.getStackBase();
llvm::AllocaInst *AI;
if (IP) {
IP = IP->getNextNode();
AI = new llvm::AllocaInst(ArgStruct, DL.getAllocaAddrSpace(),
"argmem", IP);
} else {
AI = CreateTempAlloca(ArgStruct, "argmem");
}
auto Align = CallInfo.getArgStructAlignment();
AI->setAlignment(Align.getAsAlign());
AI->setUsedWithInAlloca(true);
assert(AI->isUsedWithInAlloca() && !AI->isStaticAlloca());
ArgMemory = Address(AI, Align);
}
ClangToLLVMArgMapping IRFunctionArgs(CGM.getContext(), CallInfo);
SmallVector<llvm::Value *, 16> IRCallArgs(IRFunctionArgs.totalIRArgs());
// If the call returns a temporary with struct return, create a temporary
// alloca to hold the result, unless one is given to us.
Address SRetPtr = Address::invalid();
Address SRetAlloca = Address::invalid();
llvm::Value *UnusedReturnSizePtr = nullptr;
if (RetAI.isIndirect() || RetAI.isInAlloca() || RetAI.isCoerceAndExpand()) {
if (!ReturnValue.isNull()) {
SRetPtr = ReturnValue.getValue();
} else {
SRetPtr = CreateMemTemp(RetTy, "tmp", &SRetAlloca);
if (HaveInsertPoint() && ReturnValue.isUnused()) {
uint64_t size =
CGM.getDataLayout().getTypeAllocSize(ConvertTypeForMem(RetTy));
UnusedReturnSizePtr = EmitLifetimeStart(size, SRetAlloca.getPointer());
}
}
if (IRFunctionArgs.hasSRetArg()) {
IRCallArgs[IRFunctionArgs.getSRetArgNo()] = SRetPtr.getPointer();
} else if (RetAI.isInAlloca()) {
Address Addr =
Builder.CreateStructGEP(ArgMemory, RetAI.getInAllocaFieldIndex());
Builder.CreateStore(SRetPtr.getPointer(), Addr);
}
}
Address swiftErrorTemp = Address::invalid();
Address swiftErrorArg = Address::invalid();
// When passing arguments using temporary allocas, we need to add the
// appropriate lifetime markers. This vector keeps track of all the lifetime
// markers that need to be ended right after the call.
SmallVector<CallLifetimeEnd, 2> CallLifetimeEndAfterCall;
// Translate all of the arguments as necessary to match the IR lowering.
assert(CallInfo.arg_size() == CallArgs.size() &&
"Mismatch between function signature & arguments.");
unsigned ArgNo = 0;
CGFunctionInfo::const_arg_iterator info_it = CallInfo.arg_begin();
for (CallArgList::const_iterator I = CallArgs.begin(), E = CallArgs.end();
I != E; ++I, ++info_it, ++ArgNo) {
const ABIArgInfo &ArgInfo = info_it->info;
// Insert a padding argument to ensure proper alignment.
if (IRFunctionArgs.hasPaddingArg(ArgNo))
IRCallArgs[IRFunctionArgs.getPaddingArgNo(ArgNo)] =
llvm::UndefValue::get(ArgInfo.getPaddingType());
unsigned FirstIRArg, NumIRArgs;
std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
switch (ArgInfo.getKind()) {
case ABIArgInfo::InAlloca: {
assert(NumIRArgs == 0);
assert(getTarget().getTriple().getArch() == llvm::Triple::x86);
if (I->isAggregate()) {
Address Addr = I->hasLValue()
? I->getKnownLValue().getAddress(*this)
: 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 = CreateMemTemp(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.
Address 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());
unsigned AS = Addr.getType()->getPointerAddressSpace();
llvm::Type *MemType = ConvertTypeForMem(I->Ty)->getPointerTo(AS);
// There are some cases where a trivial bitcast is not avoidable. The
// definition of a type later in a translation unit may change it's type
// from {}* to (%struct.foo*)*.
if (Addr.getType() != MemType)
Addr = Builder.CreateBitCast(Addr, MemType);
I->copyInto(*this, Addr);
}
break;
}
case ABIArgInfo::Indirect: {
assert(NumIRArgs == 1);
if (!I->isAggregate()) {
// Make a temporary alloca to pass the argument.
Address Addr = CreateMemTempWithoutCast(
I->Ty, ArgInfo.getIndirectAlign(), "indirect-arg-temp");
IRCallArgs[FirstIRArg] = Addr.getPointer();
I->copyInto(*this, Addr);
} else {
// We want to avoid creating an unnecessary temporary+copy here;
// however, we need one in three cases:
// 1. If the argument is not byval, and we are required to copy the
// source. (This case doesn't occur on any common architecture.)
// 2. If the argument is byval, RV is not sufficiently aligned, and
// we cannot force it to be sufficiently aligned.
// 3. If the argument is byval, but RV is not located in default
// or alloca address space.
Address Addr = I->hasLValue()
? I->getKnownLValue().getAddress(*this)
: I->getKnownRValue().getAggregateAddress();
llvm::Value *V = Addr.getPointer();
CharUnits Align = ArgInfo.getIndirectAlign();
const llvm::DataLayout *TD = &CGM.getDataLayout();
assert((FirstIRArg >= IRFuncTy->getNumParams() ||
IRFuncTy->getParamType(FirstIRArg)->getPointerAddressSpace() ==
TD->getAllocaAddrSpace()) &&
"indirect argument must be in alloca address space");
bool NeedCopy = false;
if (Addr.getAlignment() < Align &&
llvm::getOrEnforceKnownAlignment(V, Align.getAsAlign(), *TD) <
Align.getAsAlign()) {
NeedCopy = true;
} else if (I->hasLValue()) {
auto LV = I->getKnownLValue();
auto AS = LV.getAddressSpace();
if (!ArgInfo.getIndirectByVal() ||
(LV.getAlignment() < getContext().getTypeAlignInChars(I->Ty))) {
NeedCopy = true;
}
if (!getLangOpts().OpenCL) {
if ((ArgInfo.getIndirectByVal() &&
(AS != LangAS::Default &&
AS != CGM.getASTAllocaAddressSpace()))) {
NeedCopy = true;
}
}
// For OpenCL even if RV is located in default or alloca address space
// we don't want to perform address space cast for it.
else if ((ArgInfo.getIndirectByVal() &&
Addr.getType()->getAddressSpace() != IRFuncTy->
getParamType(FirstIRArg)->getPointerAddressSpace())) {
NeedCopy = true;
}
}
if (NeedCopy) {
// Create an aligned temporary, and copy to it.
Address AI = CreateMemTempWithoutCast(
I->Ty, ArgInfo.getIndirectAlign(), "byval-temp");
IRCallArgs[FirstIRArg] = AI.getPointer();
// Emit lifetime markers for the temporary alloca.
uint64_t ByvalTempElementSize =
CGM.getDataLayout().getTypeAllocSize(AI.getElementType());
llvm::Value *LifetimeSize =
EmitLifetimeStart(ByvalTempElementSize, AI.getPointer());
// Add cleanup code to emit the end lifetime marker after the call.
if (LifetimeSize) // In case we disabled lifetime markers.
CallLifetimeEndAfterCall.emplace_back(AI, LifetimeSize);
// Generate the copy.
I->copyInto(*this, AI);
} else {
// Skip the extra memcpy call.
auto *T = V->getType()->getPointerElementType()->getPointerTo(
CGM.getDataLayout().getAllocaAddrSpace());
IRCallArgs[FirstIRArg] = getTargetHooks().performAddrSpaceCast(
*this, V, LangAS::Default, CGM.getASTAllocaAddressSpace(), T,
true);
}
}
break;
}
case ABIArgInfo::Ignore:
assert(NumIRArgs == 0);
break;
case ABIArgInfo::Extend:
case ABIArgInfo::Direct: {
if (!isa<llvm::StructType>(ArgInfo.getCoerceToType()) &&
ArgInfo.getCoerceToType() == ConvertType(info_it->type) &&
ArgInfo.getDirectOffset() == 0) {
assert(NumIRArgs == 1);
llvm::Value *V;
if (!I->isAggregate())
V = I->getKnownRValue().getScalarVal();
else
V = Builder.CreateLoad(
I->hasLValue() ? I->getKnownLValue().getAddress(*this)
: I->getKnownRValue().getAggregateAddress());
// Implement swifterror by copying into a new swifterror argument.
// We'll write back in the normal path out of the call.
if (CallInfo.getExtParameterInfo(ArgNo).getABI()
== ParameterABI::SwiftErrorResult) {
assert(!swiftErrorTemp.isValid() && "multiple swifterror args");
QualType pointeeTy = I->Ty->getPointeeType();
swiftErrorArg =
Address(V, getContext().getTypeAlignInChars(pointeeTy));
swiftErrorTemp =
CreateMemTemp(pointeeTy, getPointerAlign(), "swifterror.temp");
V = swiftErrorTemp.getPointer();
cast<llvm::AllocaInst>(V)->setSwiftError(true);
llvm::Value *errorValue = Builder.CreateLoad(swiftErrorArg);
Builder.CreateStore(errorValue, swiftErrorTemp);
}
// We might have to widen integers, but we should never truncate.
if (ArgInfo.getCoerceToType() != V->getType() &&
V->getType()->isIntegerTy())
V = Builder.CreateZExt(V, ArgInfo.getCoerceToType());
// If the argument doesn't match, perform a bitcast to coerce it. This
// can happen due to trivial type mismatches.
if (FirstIRArg < IRFuncTy->getNumParams() &&
V->getType() != IRFuncTy->getParamType(FirstIRArg))
V = Builder.CreateBitCast(V, IRFuncTy->getParamType(FirstIRArg));
IRCallArgs[FirstIRArg] = V;
break;
}
// FIXME: Avoid the conversion through memory if possible.
Address Src = Address::invalid();
if (!I->isAggregate()) {
Src = CreateMemTemp(I->Ty, "coerce");
I->copyInto(*this, Src);
} else {
Src = I->hasLValue() ? I->getKnownLValue().getAddress(*this)
: I->getKnownRValue().getAggregateAddress();
}
// If the value is offset in memory, apply the offset now.
Src = emitAddressAtOffset(*this, Src, ArgInfo);
// Fast-isel and the optimizer generally like scalar values better than
// FCAs, so we flatten them if this is safe to do for this argument.
llvm::StructType *STy =
dyn_cast<llvm::StructType>(ArgInfo.getCoerceToType());
if (STy && ArgInfo.isDirect() && ArgInfo.getCanBeFlattened()) {
llvm::Type *SrcTy = Src.getElementType();
uint64_t SrcSize = CGM.getDataLayout().getTypeAllocSize(SrcTy);
uint64_t DstSize = CGM.getDataLayout().getTypeAllocSize(STy);
// If the source type is smaller than the destination type of the
// coerce-to logic, copy the source value into a temp alloca the size
// of the destination type to allow loading all of it. The bits past
// the source value are left undef.
if (SrcSize < DstSize) {
Address TempAlloca
= CreateTempAlloca(STy, Src.getAlignment(),
Src.getName() + ".coerce");
Builder.CreateMemCpy(TempAlloca, Src, SrcSize);
Src = TempAlloca;
} else {
Src = Builder.CreateBitCast(Src,
STy->getPointerTo(Src.getAddressSpace()));
}
assert(NumIRArgs == STy->getNumElements());
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
Address EltPtr = Builder.CreateStructGEP(Src, i);
llvm::Value *LI = Builder.CreateLoad(EltPtr);
IRCallArgs[FirstIRArg + i] = LI;
}
} else {
// In the simple case, just pass the coerced loaded value.
assert(NumIRArgs == 1);
llvm::Value *Load =
CreateCoercedLoad(Src, 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);
}
IRCallArgs[FirstIRArg] = Load;
}
break;
}
case ABIArgInfo::CoerceAndExpand: {
auto coercionType = ArgInfo.getCoerceAndExpandType();
auto layout = CGM.getDataLayout().getStructLayout(coercionType);
llvm::Value *tempSize = nullptr;
Address addr = Address::invalid();
Address AllocaAddr = Address::invalid();
if (I->isAggregate()) {
addr = I->hasLValue() ? I->getKnownLValue().getAddress(*this)
: I->getKnownRValue().getAggregateAddress();
} else {
RValue RV = I->getKnownRValue();
assert(RV.isScalar()); // complex should always just be direct
llvm::Type *scalarType = RV.getScalarVal()->getType();
auto scalarSize = CGM.getDataLayout().getTypeAllocSize(scalarType);
auto scalarAlign = CGM.getDataLayout().getPrefTypeAlignment(scalarType);
// Materialize to a temporary.
addr = CreateTempAlloca(
RV.getScalarVal()->getType(),
CharUnits::fromQuantity(std::max(
(unsigned)layout->getAlignment().value(), scalarAlign)),
"tmp",
/*ArraySize=*/nullptr, &AllocaAddr);
tempSize = EmitLifetimeStart(scalarSize, AllocaAddr.getPointer());
Builder.CreateStore(RV.getScalarVal(), addr);
}
addr = Builder.CreateElementBitCast(addr, coercionType);
unsigned IRArgPos = FirstIRArg;
for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) {
llvm::Type *eltType = coercionType->getElementType(i);
if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType)) continue;
Address eltAddr = Builder.CreateStructGEP(addr, i);
llvm::Value *elt = Builder.CreateLoad(eltAddr);
IRCallArgs[IRArgPos++] = elt;
}
assert(IRArgPos == FirstIRArg + NumIRArgs);
if (tempSize) {
EmitLifetimeEnd(tempSize, AllocaAddr.getPointer());
}
break;
}
case ABIArgInfo::Expand:
unsigned IRArgPos = FirstIRArg;
ExpandTypeToArgs(I->Ty, *I, IRFuncTy, IRCallArgs, IRArgPos);
assert(IRArgPos == FirstIRArg + NumIRArgs);
break;
}
}
const CGCallee &ConcreteCallee = Callee.prepareConcreteCallee(*this);
llvm::Value *CalleePtr = ConcreteCallee.getFunctionPointer();
// If we're using inalloca, set up that argument.
if (ArgMemory.isValid()) {
llvm::Value *Arg = ArgMemory.getPointer();
if (CallInfo.isVariadic()) {
// When passing non-POD arguments by value to variadic functions, we will
// end up with a variadic prototype and an inalloca call site. In such
// cases, we can't do any parameter mismatch checks. Give up and bitcast
// the callee.
unsigned CalleeAS = CalleePtr->getType()->getPointerAddressSpace();
CalleePtr =
Builder.CreateBitCast(CalleePtr, IRFuncTy->getPointerTo(CalleeAS));
} else {
llvm::Type *LastParamTy =
IRFuncTy->getParamType(IRFuncTy->getNumParams() - 1);
if (Arg->getType() != LastParamTy) {
#ifndef NDEBUG
// Assert that these structs have equivalent element types.
llvm::StructType *FullTy = CallInfo.getArgStruct();
llvm::StructType *DeclaredTy = cast<llvm::StructType>(
cast<llvm::PointerType>(LastParamTy)->getElementType());
assert(DeclaredTy->getNumElements() == FullTy->getNumElements());
for (llvm::StructType::element_iterator DI = DeclaredTy->element_begin(),
DE = DeclaredTy->element_end(),
FI = FullTy->element_begin();
DI != DE; ++DI, ++FI)
assert(*DI == *FI);
#endif
Arg = Builder.CreateBitCast(Arg, LastParamTy);
}
}
assert(IRFunctionArgs.hasInallocaArg());
IRCallArgs[IRFunctionArgs.getInallocaArgNo()] = Arg;
}
// 2. Prepare the function pointer.
// If the callee is a bitcast of a non-variadic function to have a
// variadic function pointer type, check to see if we can remove the
// bitcast. This comes up with unprototyped functions.
//
// This makes the IR nicer, but more importantly it ensures that we
// can inline the function at -O0 if it is marked always_inline.
auto simplifyVariadicCallee = [](llvm::FunctionType *CalleeFT,
llvm::Value *Ptr) -> llvm::Function * {
if (!CalleeFT->isVarArg())
return nullptr;
// Get underlying value if it's a bitcast
if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Ptr)) {
if (CE->getOpcode() == llvm::Instruction::BitCast)
Ptr = CE->getOperand(0);
}
llvm::Function *OrigFn = dyn_cast<llvm::Function>(Ptr);
if (!OrigFn)
return nullptr;
llvm::FunctionType *OrigFT = OrigFn->getFunctionType();
// If the original type is variadic, or if any of the component types
// disagree, we cannot remove the cast.
if (OrigFT->isVarArg() ||
OrigFT->getNumParams() != CalleeFT->getNumParams() ||
OrigFT->getReturnType() != CalleeFT->getReturnType())
return nullptr;
for (unsigned i = 0, e = OrigFT->getNumParams(); i != e; ++i)
if (OrigFT->getParamType(i) != CalleeFT->getParamType(i))
return nullptr;
return OrigFn;
};
if (llvm::Function *OrigFn = simplifyVariadicCallee(IRFuncTy, CalleePtr)) {
CalleePtr = OrigFn;
IRFuncTy = OrigFn->getFunctionType();
}
// 3. Perform the actual call.
// Deactivate any cleanups that we're supposed to do immediately before
// the call.
if (!CallArgs.getCleanupsToDeactivate().empty())
deactivateArgCleanupsBeforeCall(*this, CallArgs);
// Assert that the arguments we computed match up. The IR verifier
// will catch this, but this is a common enough source of problems
// during IRGen changes that it's way better for debugging to catch
// it ourselves here.
#ifndef NDEBUG
assert(IRCallArgs.size() == IRFuncTy->getNumParams() || IRFuncTy->isVarArg());
for (unsigned i = 0; i < IRCallArgs.size(); ++i) {
// Inalloca argument can have different type.
if (IRFunctionArgs.hasInallocaArg() &&
i == IRFunctionArgs.getInallocaArgNo())
continue;
if (i < IRFuncTy->getNumParams())
assert(IRCallArgs[i]->getType() == IRFuncTy->getParamType(i));
}
#endif
// Update the largest vector width if any arguments have vector types.
for (unsigned i = 0; i < IRCallArgs.size(); ++i) {
if (auto *VT = dyn_cast<llvm::VectorType>(IRCallArgs[i]->getType()))
LargestVectorWidth =
std::max((uint64_t)LargestVectorWidth,
VT->getPrimitiveSizeInBits().getKnownMinSize());
}
// Compute the calling convention and attributes.
unsigned CallingConv;
llvm::AttributeList Attrs;
CGM.ConstructAttributeList(CalleePtr->getName(), CallInfo,
Callee.getAbstractInfo(), Attrs, CallingConv,
/*AttrOnCallSite=*/true);
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl))
if (FD->usesFPIntrin())
// All calls within a strictfp function are marked strictfp
Attrs =
Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex,
llvm::Attribute::StrictFP);
// Add call-site nomerge attribute if exists.
if (InNoMergeAttributedStmt)
Attrs =
Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex,
llvm::Attribute::NoMerge);
// Apply some call-site-specific attributes.
// TODO: work this into building the attribute set.
// Apply always_inline to all calls within flatten functions.
// FIXME: should this really take priority over __try, below?
if (CurCodeDecl && CurCodeDecl->hasAttr<FlattenAttr>() &&
!(TargetDecl && TargetDecl->hasAttr<NoInlineAttr>())) {
Attrs =
Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex,
llvm::Attribute::AlwaysInline);
}
// Disable inlining inside SEH __try blocks.
if (isSEHTryScope()) {
Attrs =
Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex,
llvm::Attribute::NoInline);
}
// Decide whether to use a call or an invoke.
bool CannotThrow;
if (currentFunctionUsesSEHTry()) {
// SEH cares about asynchronous exceptions, so everything can "throw."
CannotThrow = false;
} else if (isCleanupPadScope() &&
EHPersonality::get(*this).isMSVCXXPersonality()) {
// The MSVC++ personality will implicitly terminate the program if an
// exception is thrown during a cleanup outside of a try/catch.
// We don't need to model anything in IR to get this behavior.
CannotThrow = true;
} else {
// Otherwise, nounwind call sites will never throw.
CannotThrow = Attrs.hasFnAttribute(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.
if (UnusedReturnSizePtr)
pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, SRetAlloca,
UnusedReturnSizePtr);
llvm::BasicBlock *InvokeDest = CannotThrow ? nullptr : getInvokeDest();
SmallVector<llvm::OperandBundleDef, 1> BundleList =
getBundlesForFunclet(CalleePtr);
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl))
if (FD->usesFPIntrin())
// All calls within a strictfp function are marked strictfp
Attrs =
Attrs.addAttribute(getLLVMContext(), llvm::AttributeList::FunctionIndex,
llvm::Attribute::StrictFP);
AssumeAlignedAttrEmitter AssumeAlignedAttrEmitter(*this, TargetDecl);
Attrs = AssumeAlignedAttrEmitter.TryEmitAsCallSiteAttribute(Attrs);
AllocAlignAttrEmitter AllocAlignAttrEmitter(*this, TargetDecl, CallArgs);
Attrs = AllocAlignAttrEmitter.TryEmitAsCallSiteAttribute(Attrs);
// Emit the actual call/invoke instruction.
llvm::CallBase *CI;
if (!InvokeDest) {
CI = Builder.CreateCall(IRFuncTy, CalleePtr, IRCallArgs, BundleList);
} else {
llvm::BasicBlock *Cont = createBasicBlock("invoke.cont");
CI = Builder.CreateInvoke(IRFuncTy, CalleePtr, Cont, InvokeDest, IRCallArgs,
BundleList);
EmitBlock(Cont);
}
if (callOrInvoke)
*callOrInvoke = CI;
// 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.addAttribute(
getLLVMContext(), llvm::AttributeList::FunctionIndex, "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.
if (auto *VT = dyn_cast<llvm::VectorType>(CI->getType()))
LargestVectorWidth =
std::max((uint64_t)LargestVectorWidth,
VT->getPrimitiveSizeInBits().getKnownMinSize());
// Insert instrumentation or attach profile metadata at indirect call sites.
// For more details, see the comment before the definition of
// IPVK_IndirectCallTarget in InstrProfData.inc.
if (!CI->getCalledFunction())
PGO.valueProfile(Builder, llvm::IPVK_IndirectCallTarget,
CI, CalleePtr);
// In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
// optimizer it can aggressively ignore unwind edges.
if (CGM.getLangOpts().ObjCAutoRefCount)
AddObjCARCExceptionMetadata(CI);
// Suppress tail calls if requested.
if (llvm::CallInst *Call = dyn_cast<llvm::CallInst>(CI)) {
if (TargetDecl && TargetDecl->hasAttr<NotTailCalledAttr>())
Call->setTailCallKind(llvm::CallInst::TCK_NoTail);
}
// Add metadata for calls to MSAllocator functions
if (getDebugInfo() && TargetDecl &&
TargetDecl->hasAttr<MSAllocatorAttr>())
getDebugInfo()->addHeapAllocSiteMetadata(CI, RetTy->getPointeeType(), Loc);
// 4. Finish the call.
// If the call doesn't return, finish the basic block and clear the
// insertion point; this allows the rest of IRGen to discard
// unreachable code.
if (CI->doesNotReturn()) {
if (UnusedReturnSizePtr)
PopCleanupBlock();
// Strip away the noreturn attribute to better diagnose unreachable UB.
if (SanOpts.has(SanitizerKind::Unreachable)) {
// Also remove from function since CallBase::hasFnAttr additionally checks
// attributes of the called function.
if (auto *F = CI->getCalledFunction())
F->removeFnAttr(llvm::Attribute::NoReturn);
CI->removeAttribute(llvm::AttributeList::FunctionIndex,
llvm::Attribute::NoReturn);
// Avoid incompatibility with ASan which relies on the `noreturn`
// attribute to insert handler calls.
if (SanOpts.hasOneOf(SanitizerKind::Address |
SanitizerKind::KernelAddress)) {
SanitizerScope SanScope(this);
llvm::IRBuilder<>::InsertPointGuard IPGuard(Builder);
Builder.SetInsertPoint(CI);
auto *FnType = llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
llvm::FunctionCallee Fn =
CGM.CreateRuntimeFunction(FnType, "__asan_handle_no_return");
EmitNounwindRuntimeCall(Fn);
}
}
EmitUnreachable(Loc);
Builder.ClearInsertionPoint();
// FIXME: For now, emit a dummy basic block because expr emitters in
// generally are not ready to handle emitting expressions at unreachable
// points.
EnsureInsertPoint();
// Return a reasonable RValue.
return GetUndefRValue(RetTy);
}
// Perform the swifterror writeback.
if (swiftErrorTemp.isValid()) {
llvm::Value *errorResult = Builder.CreateLoad(swiftErrorTemp);
Builder.CreateStore(errorResult, swiftErrorArg);
}
// Emit any call-associated writebacks immediately. Arguably this
// should happen after any return-value munging.
if (CallArgs.hasWritebacks())
emitWritebacks(*this, CallArgs);
// The stack cleanup for inalloca arguments has to run out of the normal
// lexical order, so deactivate it and run it manually here.
CallArgs.freeArgumentMemory(*this);
// Extract the return value.
RValue Ret = [&] {
switch (RetAI.getKind()) {
case ABIArgInfo::CoerceAndExpand: {
auto coercionType = RetAI.getCoerceAndExpandType();
Address addr = SRetPtr;
addr = Builder.CreateElementBitCast(addr, coercionType);
assert(CI->getType() == RetAI.getUnpaddedCoerceAndExpandType());
bool requiresExtract = isa<llvm::StructType>(CI->getType());
unsigned unpaddedIndex = 0;
for (unsigned i = 0, e = coercionType->getNumElements(); i != e; ++i) {
llvm::Type *eltType = coercionType->getElementType(i);
if (ABIArgInfo::isPaddingForCoerceAndExpand(eltType)) continue;
Address eltAddr = Builder.CreateStructGEP(addr, i);
llvm::Value *elt = CI;
if (requiresExtract)
elt = Builder.CreateExtractValue(elt, unpaddedIndex++);
else
assert(unpaddedIndex == 0);
Builder.CreateStore(elt, eltAddr);
}
// FALLTHROUGH
LLVM_FALLTHROUGH;
}
case ABIArgInfo::InAlloca:
case ABIArgInfo::Indirect: {
RValue ret = convertTempToRValue(SRetPtr, RetTy, SourceLocation());
if (UnusedReturnSizePtr)
PopCleanupBlock();
return ret;
}
case ABIArgInfo::Ignore:
// If we are ignoring an argument that had a result, make sure to
// construct the appropriate return value for our caller.
return GetUndefRValue(RetTy);
case ABIArgInfo::Extend:
case ABIArgInfo::Direct: {
llvm::Type *RetIRTy = ConvertType(RetTy);
if (RetAI.getCoerceToType() == RetIRTy && RetAI.getDirectOffset() == 0) {
switch (getEvaluationKind(RetTy)) {
case TEK_Complex: {
llvm::Value *Real = Builder.CreateExtractValue(CI, 0);
llvm::Value *Imag = Builder.CreateExtractValue(CI, 1);
return RValue::getComplex(std::make_pair(Real, Imag));
}
case TEK_Aggregate: {
Address DestPtr = ReturnValue.getValue();
bool DestIsVolatile = ReturnValue.isVolatile();
if (!DestPtr.isValid()) {
DestPtr = CreateMemTemp(RetTy, "agg.tmp");
DestIsVolatile = false;
}
EmitAggregateStore(CI, DestPtr, DestIsVolatile);
return RValue::getAggregate(DestPtr);
}
case TEK_Scalar: {
// If the argument doesn't match, perform a bitcast to coerce it. This
// can happen due to trivial type mismatches.
llvm::Value *V = CI;
if (V->getType() != RetIRTy)
V = Builder.CreateBitCast(V, RetIRTy);
return RValue::get(V);
}
}
llvm_unreachable("bad evaluation kind");
}
Address DestPtr = ReturnValue.getValue();
bool DestIsVolatile = ReturnValue.isVolatile();
if (!DestPtr.isValid()) {
DestPtr = CreateMemTemp(RetTy, "coerce");
DestIsVolatile = false;
}
// If the value is offset in memory, apply the offset now.
Address StorePtr = emitAddressAtOffset(*this, DestPtr, RetAI);
CreateCoercedStore(CI, StorePtr, DestIsVolatile, *this);
return convertTempToRValue(DestPtr, RetTy, SourceLocation());
}
case ABIArgInfo::Expand:
llvm_unreachable("Invalid ABI kind for return argument");
}
llvm_unreachable("Unhandled ABIArgInfo::Kind");
} ();
// Emit the assume_aligned check on the return value.
if (Ret.isScalar() && TargetDecl) {
AssumeAlignedAttrEmitter.EmitAsAnAssumption(Loc, RetTy, Ret);
AllocAlignAttrEmitter.EmitAsAnAssumption(Loc, RetTy, Ret);
}
// Explicitly call CallLifetimeEnd::Emit just to re-use the code even though
// we can't use the full cleanup mechanism.
for (CallLifetimeEnd &LifetimeEnd : CallLifetimeEndAfterCall)
LifetimeEnd.Emit(*this, /*Flags=*/{});
if (!ReturnValue.isExternallyDestructed() &&
RetTy.isDestructedType() == QualType::DK_nontrivial_c_struct)
pushDestroy(QualType::DK_nontrivial_c_struct, Ret.getAggregateAddress(),
RetTy);
return Ret;
}
CGCallee CGCallee::prepareConcreteCallee(CodeGenFunction &CGF) const {
if (isVirtual()) {
const CallExpr *CE = getVirtualCallExpr();
return CGF.CGM.getCXXABI().getVirtualFunctionPointer(
CGF, getVirtualMethodDecl(), getThisAddress(), getVirtualFunctionType(),
CE ? CE->getBeginLoc() : SourceLocation());
}
return *this;
}
/* VarArg handling */
Address CodeGenFunction::EmitVAArg(VAArgExpr *VE, Address &VAListAddr) {
VAListAddr = VE->isMicrosoftABI()
? EmitMSVAListRef(VE->getSubExpr())
: EmitVAListRef(VE->getSubExpr());
QualType Ty = VE->getType();
if (VE->isMicrosoftABI())
return CGM.getTypes().getABIInfo().EmitMSVAArg(*this, VAListAddr, Ty);
return CGM.getTypes().getABIInfo().EmitVAArg(*this, VAListAddr, Ty);
}
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