#include "CGCXXABI.h"
#include "CGCleanup.h"
#include "CGRecordLayout.h"
#include "CGVTables.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "TargetInfo.h"
#include "clang/AST/Mangle.h"
#include "clang/AST/Type.h"
#include "clang/AST/StmtCXX.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Value.h"
using namespace clang;
using namespace CodeGen;
namespace {
class ItaniumCXXABI : public CodeGen::CGCXXABI {
llvm::DenseMap<const CXXRecordDecl *, llvm::GlobalVariable *> VTables;
protected:
bool UseARMMethodPtrABI;
bool UseARMGuardVarABI;
ItaniumMangleContext &getMangleContext() {
return cast<ItaniumMangleContext>(CodeGen::CGCXXABI::getMangleContext());
}
public:
ItaniumCXXABI(CodeGen::CodeGenModule &CGM,
bool UseARMMethodPtrABI = false,
bool UseARMGuardVarABI = false) :
CGCXXABI(CGM), UseARMMethodPtrABI(UseARMMethodPtrABI),
UseARMGuardVarABI(UseARMGuardVarABI) { }
bool classifyReturnType(CGFunctionInfo &FI) const override;
RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const override {
if (RD->hasNonTrivialDestructor() || RD->hasNonTrivialCopyConstructor())
return RAA_Indirect;
return RAA_Default;
}
bool isThisCompleteObject(GlobalDecl GD) const override {
if (isa<CXXDestructorDecl>(GD.getDecl())) {
switch (GD.getDtorType()) {
case Dtor_Complete:
case Dtor_Deleting:
return true;
case Dtor_Base:
return false;
case Dtor_Comdat:
llvm_unreachable("emitting dtor comdat as function?");
}
llvm_unreachable("bad dtor kind");
}
if (isa<CXXConstructorDecl>(GD.getDecl())) {
switch (GD.getCtorType()) {
case Ctor_Complete:
return true;
case Ctor_Base:
return false;
case Ctor_CopyingClosure:
case Ctor_DefaultClosure:
llvm_unreachable("closure ctors in Itanium ABI?");
case Ctor_Comdat:
llvm_unreachable("emitting ctor comdat as function?");
}
llvm_unreachable("bad dtor kind");
}
return false;
}
bool isZeroInitializable(const MemberPointerType *MPT) override;
llvm::Type *ConvertMemberPointerType(const MemberPointerType *MPT) override;
llvm::Value *
EmitLoadOfMemberFunctionPointer(CodeGenFunction &CGF,
const Expr *E,
Address This,
llvm::Value *&ThisPtrForCall,
llvm::Value *MemFnPtr,
const MemberPointerType *MPT) override;
llvm::Value *
EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
Address Base,
llvm::Value *MemPtr,
const MemberPointerType *MPT) override;
llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
const CastExpr *E,
llvm::Value *Src) override;
llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
llvm::Constant *Src) override;
llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT) override;
llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD) override;
llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
CharUnits offset) override;
llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT) override;
llvm::Constant *BuildMemberPointer(const CXXMethodDecl *MD,
CharUnits ThisAdjustment);
llvm::Value *EmitMemberPointerComparison(CodeGenFunction &CGF,
llvm::Value *L, llvm::Value *R,
const MemberPointerType *MPT,
bool Inequality) override;
llvm::Value *EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
llvm::Value *Addr,
const MemberPointerType *MPT) override;
void emitVirtualObjectDelete(CodeGenFunction &CGF, const CXXDeleteExpr *DE,
Address Ptr, QualType ElementType,
const CXXDestructorDecl *Dtor) override;
CharUnits getAlignmentOfExnObject() {
unsigned Align = CGM.getContext().getTargetInfo().getExnObjectAlignment();
return CGM.getContext().toCharUnitsFromBits(Align);
}
void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) override;
void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) override;
void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) override;
llvm::CallInst *
emitTerminateForUnexpectedException(CodeGenFunction &CGF,
llvm::Value *Exn) override;
void EmitFundamentalRTTIDescriptor(QualType Type);
void EmitFundamentalRTTIDescriptors();
llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) override;
CatchTypeInfo
getAddrOfCXXCatchHandlerType(QualType Ty,
QualType CatchHandlerType) override {
return CatchTypeInfo{getAddrOfRTTIDescriptor(Ty), 0};
}
bool shouldTypeidBeNullChecked(bool IsDeref, QualType SrcRecordTy) override;
void EmitBadTypeidCall(CodeGenFunction &CGF) override;
llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
Address ThisPtr,
llvm::Type *StdTypeInfoPtrTy) override;
bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
QualType SrcRecordTy) override;
llvm::Value *EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
QualType SrcRecordTy, QualType DestTy,
QualType DestRecordTy,
llvm::BasicBlock *CastEnd) override;
llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF, Address Value,
QualType SrcRecordTy,
QualType DestTy) override;
bool EmitBadCastCall(CodeGenFunction &CGF) override;
llvm::Value *
GetVirtualBaseClassOffset(CodeGenFunction &CGF, Address This,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl) override;
void EmitCXXConstructors(const CXXConstructorDecl *D) override;
void buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
SmallVectorImpl<CanQualType> &ArgTys) override;
bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
CXXDtorType DT) const override {
return false;
}
void EmitCXXDestructors(const CXXDestructorDecl *D) override;
void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
FunctionArgList &Params) override;
void EmitInstanceFunctionProlog(CodeGenFunction &CGF) override;
unsigned addImplicitConstructorArgs(CodeGenFunction &CGF,
const CXXConstructorDecl *D,
CXXCtorType Type, bool ForVirtualBase,
bool Delegating,
CallArgList &Args) override;
void EmitDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *DD,
CXXDtorType Type, bool ForVirtualBase,
bool Delegating, Address This) override;
void emitVTableDefinitions(CodeGenVTables &CGVT,
const CXXRecordDecl *RD) override;
bool isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
CodeGenFunction::VPtr Vptr) override;
bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) override {
return true;
}
llvm::Constant *
getVTableAddressPoint(BaseSubobject Base,
const CXXRecordDecl *VTableClass) override;
llvm::Value *getVTableAddressPointInStructor(
CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
BaseSubobject Base, const CXXRecordDecl *NearestVBase) override;
llvm::Value *getVTableAddressPointInStructorWithVTT(
CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
BaseSubobject Base, const CXXRecordDecl *NearestVBase);
llvm::Constant *
getVTableAddressPointForConstExpr(BaseSubobject Base,
const CXXRecordDecl *VTableClass) override;
llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
CharUnits VPtrOffset) override;
llvm::Value *getVirtualFunctionPointer(CodeGenFunction &CGF, GlobalDecl GD,
Address This, llvm::Type *Ty,
SourceLocation Loc) override;
llvm::Value *EmitVirtualDestructorCall(CodeGenFunction &CGF,
const CXXDestructorDecl *Dtor,
CXXDtorType DtorType,
Address This,
const CXXMemberCallExpr *CE) override;
void emitVirtualInheritanceTables(const CXXRecordDecl *RD) override;
bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const override;
void setThunkLinkage(llvm::Function *Thunk, bool ForVTable, GlobalDecl GD,
bool ReturnAdjustment) override {
if (ForVTable && !Thunk->hasLocalLinkage())
Thunk->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage);
}
llvm::Value *performThisAdjustment(CodeGenFunction &CGF, Address This,
const ThisAdjustment &TA) override;
llvm::Value *performReturnAdjustment(CodeGenFunction &CGF, Address Ret,
const ReturnAdjustment &RA) override;
size_t getSrcArgforCopyCtor(const CXXConstructorDecl *,
FunctionArgList &Args) const override {
assert(!Args.empty() && "expected the arglist to not be empty!");
return Args.size() - 1;
}
StringRef GetPureVirtualCallName() override { return "__cxa_pure_virtual"; }
StringRef GetDeletedVirtualCallName() override
{ return "__cxa_deleted_virtual"; }
CharUnits getArrayCookieSizeImpl(QualType elementType) override;
Address InitializeArrayCookie(CodeGenFunction &CGF,
Address NewPtr,
llvm::Value *NumElements,
const CXXNewExpr *expr,
QualType ElementType) override;
llvm::Value *readArrayCookieImpl(CodeGenFunction &CGF,
Address allocPtr,
CharUnits cookieSize) override;
void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
llvm::GlobalVariable *DeclPtr,
bool PerformInit) override;
void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
llvm::Constant *dtor, llvm::Constant *addr) override;
llvm::Function *getOrCreateThreadLocalWrapper(const VarDecl *VD,
llvm::Value *Val);
void EmitThreadLocalInitFuncs(
CodeGenModule &CGM,
ArrayRef<const VarDecl *> CXXThreadLocals,
ArrayRef<llvm::Function *> CXXThreadLocalInits,
ArrayRef<const VarDecl *> CXXThreadLocalInitVars) override;
bool usesThreadWrapperFunction() const override { return true; }
LValue EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF, const VarDecl *VD,
QualType LValType) override;
bool NeedsVTTParameter(GlobalDecl GD) override;
protected:
virtual bool shouldRTTIBeUnique() const { return true; }
public:
enum RTTIUniquenessKind {
RUK_Unique,
RUK_NonUniqueHidden,
RUK_NonUniqueVisible
};
RTTIUniquenessKind
classifyRTTIUniqueness(QualType CanTy,
llvm::GlobalValue::LinkageTypes Linkage) const;
friend class ItaniumRTTIBuilder;
void emitCXXStructor(const CXXMethodDecl *MD, StructorType Type) override;
private:
bool hasAnyUsedVirtualInlineFunction(const CXXRecordDecl *RD) const {
const auto &VtableLayout =
CGM.getItaniumVTableContext().getVTableLayout(RD);
for (const auto &VtableComponent : VtableLayout.vtable_components()) {
if (!VtableComponent.isUsedFunctionPointerKind())
continue;
const CXXMethodDecl *Method = VtableComponent.getFunctionDecl();
if (Method->getCanonicalDecl()->isInlined())
return true;
}
return false;
}
bool isVTableHidden(const CXXRecordDecl *RD) const {
const auto &VtableLayout =
CGM.getItaniumVTableContext().getVTableLayout(RD);
for (const auto &VtableComponent : VtableLayout.vtable_components()) {
if (VtableComponent.isRTTIKind()) {
const CXXRecordDecl *RTTIDecl = VtableComponent.getRTTIDecl();
if (RTTIDecl->getVisibility() == Visibility::HiddenVisibility)
return true;
} else if (VtableComponent.isUsedFunctionPointerKind()) {
const CXXMethodDecl *Method = VtableComponent.getFunctionDecl();
if (Method->getVisibility() == Visibility::HiddenVisibility &&
!Method->isDefined())
return true;
}
}
return false;
}
};
class ARMCXXABI : public ItaniumCXXABI {
public:
ARMCXXABI(CodeGen::CodeGenModule &CGM) :
ItaniumCXXABI(CGM, true,
true) {}
bool HasThisReturn(GlobalDecl GD) const override {
return (isa<CXXConstructorDecl>(GD.getDecl()) || (
isa<CXXDestructorDecl>(GD.getDecl()) &&
GD.getDtorType() != Dtor_Deleting));
}
void EmitReturnFromThunk(CodeGenFunction &CGF, RValue RV,
QualType ResTy) override;
CharUnits getArrayCookieSizeImpl(QualType elementType) override;
Address InitializeArrayCookie(CodeGenFunction &CGF,
Address NewPtr,
llvm::Value *NumElements,
const CXXNewExpr *expr,
QualType ElementType) override;
llvm::Value *readArrayCookieImpl(CodeGenFunction &CGF, Address allocPtr,
CharUnits cookieSize) override;
};
class iOS64CXXABI : public ARMCXXABI {
public:
iOS64CXXABI(CodeGen::CodeGenModule &CGM) : ARMCXXABI(CGM) {}
bool shouldRTTIBeUnique() const override { return false; }
};
class WebAssemblyCXXABI final : public ItaniumCXXABI {
public:
explicit WebAssemblyCXXABI(CodeGen::CodeGenModule &CGM)
: ItaniumCXXABI(CGM, true,
true) {}
private:
bool HasThisReturn(GlobalDecl GD) const override {
return isa<CXXConstructorDecl>(GD.getDecl()) ||
(isa<CXXDestructorDecl>(GD.getDecl()) &&
GD.getDtorType() != Dtor_Deleting);
}
};
}
CodeGen::CGCXXABI *CodeGen::CreateItaniumCXXABI(CodeGenModule &CGM) {
switch (CGM.getTarget().getCXXABI().getKind()) {
case TargetCXXABI::GenericARM:
case TargetCXXABI::iOS:
case TargetCXXABI::WatchOS:
return new ARMCXXABI(CGM);
case TargetCXXABI::iOS64:
return new iOS64CXXABI(CGM);
case TargetCXXABI::GenericAArch64:
return new ItaniumCXXABI(CGM, true,
true);
case TargetCXXABI::GenericMIPS:
return new ItaniumCXXABI(CGM, true);
case TargetCXXABI::WebAssembly:
return new WebAssemblyCXXABI(CGM);
case TargetCXXABI::GenericItanium:
if (CGM.getContext().getTargetInfo().getTriple().getArch()
== llvm::Triple::le32) {
return new ItaniumCXXABI(CGM, true,
false);
}
return new ItaniumCXXABI(CGM);
case TargetCXXABI::Microsoft:
llvm_unreachable("Microsoft ABI is not Itanium-based");
}
llvm_unreachable("bad ABI kind");
}
llvm::Type *
ItaniumCXXABI::ConvertMemberPointerType(const MemberPointerType *MPT) {
if (MPT->isMemberDataPointer())
return CGM.PtrDiffTy;
return llvm::StructType::get(CGM.PtrDiffTy, CGM.PtrDiffTy, nullptr);
}
llvm::Value *ItaniumCXXABI::EmitLoadOfMemberFunctionPointer(
CodeGenFunction &CGF, const Expr *E, Address ThisAddr,
llvm::Value *&ThisPtrForCall,
llvm::Value *MemFnPtr, const MemberPointerType *MPT) {
CGBuilderTy &Builder = CGF.Builder;
const FunctionProtoType *FPT =
MPT->getPointeeType()->getAs<FunctionProtoType>();
const CXXRecordDecl *RD =
cast<CXXRecordDecl>(MPT->getClass()->getAs<RecordType>()->getDecl());
llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(
CGM.getTypes().arrangeCXXMethodType(RD, FPT, nullptr));
llvm::Constant *ptrdiff_1 = llvm::ConstantInt::get(CGM.PtrDiffTy, 1);
llvm::BasicBlock *FnVirtual = CGF.createBasicBlock("memptr.virtual");
llvm::BasicBlock *FnNonVirtual = CGF.createBasicBlock("memptr.nonvirtual");
llvm::BasicBlock *FnEnd = CGF.createBasicBlock("memptr.end");
llvm::Value *RawAdj = Builder.CreateExtractValue(MemFnPtr, 1, "memptr.adj");
llvm::Value *Adj = RawAdj;
if (UseARMMethodPtrABI)
Adj = Builder.CreateAShr(Adj, ptrdiff_1, "memptr.adj.shifted");
llvm::Value *This = ThisAddr.getPointer();
llvm::Value *Ptr = Builder.CreateBitCast(This, Builder.getInt8PtrTy());
Ptr = Builder.CreateInBoundsGEP(Ptr, Adj);
This = Builder.CreateBitCast(Ptr, This->getType(), "this.adjusted");
ThisPtrForCall = This;
llvm::Value *FnAsInt = Builder.CreateExtractValue(MemFnPtr, 0, "memptr.ptr");
llvm::Value *IsVirtual;
if (UseARMMethodPtrABI)
IsVirtual = Builder.CreateAnd(RawAdj, ptrdiff_1);
else
IsVirtual = Builder.CreateAnd(FnAsInt, ptrdiff_1);
IsVirtual = Builder.CreateIsNotNull(IsVirtual, "memptr.isvirtual");
Builder.CreateCondBr(IsVirtual, FnVirtual, FnNonVirtual);
CGF.EmitBlock(FnVirtual);
llvm::Type *VTableTy = Builder.getInt8PtrTy();
CharUnits VTablePtrAlign =
CGF.CGM.getDynamicOffsetAlignment(ThisAddr.getAlignment(), RD,
CGF.getPointerAlign());
llvm::Value *VTable =
CGF.GetVTablePtr(Address(This, VTablePtrAlign), VTableTy, RD);
llvm::Value *VTableOffset = FnAsInt;
if (!UseARMMethodPtrABI)
VTableOffset = Builder.CreateSub(VTableOffset, ptrdiff_1);
VTable = Builder.CreateGEP(VTable, VTableOffset);
VTable = Builder.CreateBitCast(VTable, FTy->getPointerTo()->getPointerTo());
llvm::Value *VirtualFn =
Builder.CreateAlignedLoad(VTable, CGF.getPointerAlign(),
"memptr.virtualfn");
CGF.EmitBranch(FnEnd);
CGF.EmitBlock(FnNonVirtual);
llvm::Value *NonVirtualFn =
Builder.CreateIntToPtr(FnAsInt, FTy->getPointerTo(), "memptr.nonvirtualfn");
CGF.EmitBlock(FnEnd);
llvm::PHINode *Callee = Builder.CreatePHI(FTy->getPointerTo(), 2);
Callee->addIncoming(VirtualFn, FnVirtual);
Callee->addIncoming(NonVirtualFn, FnNonVirtual);
return Callee;
}
llvm::Value *ItaniumCXXABI::EmitMemberDataPointerAddress(
CodeGenFunction &CGF, const Expr *E, Address Base, llvm::Value *MemPtr,
const MemberPointerType *MPT) {
assert(MemPtr->getType() == CGM.PtrDiffTy);
CGBuilderTy &Builder = CGF.Builder;
Base = Builder.CreateElementBitCast(Base, CGF.Int8Ty);
llvm::Value *Addr =
Builder.CreateInBoundsGEP(Base.getPointer(), MemPtr, "memptr.offset");
llvm::Type *PType = CGF.ConvertTypeForMem(MPT->getPointeeType())
->getPointerTo(Base.getAddressSpace());
return Builder.CreateBitCast(Addr, PType);
}
llvm::Value *
ItaniumCXXABI::EmitMemberPointerConversion(CodeGenFunction &CGF,
const CastExpr *E,
llvm::Value *src) {
assert(E->getCastKind() == CK_DerivedToBaseMemberPointer ||
E->getCastKind() == CK_BaseToDerivedMemberPointer ||
E->getCastKind() == CK_ReinterpretMemberPointer);
if (E->getCastKind() == CK_ReinterpretMemberPointer) return src;
if (isa<llvm::Constant>(src))
return EmitMemberPointerConversion(E, cast<llvm::Constant>(src));
llvm::Constant *adj = getMemberPointerAdjustment(E);
if (!adj) return src;
CGBuilderTy &Builder = CGF.Builder;
bool isDerivedToBase = (E->getCastKind() == CK_DerivedToBaseMemberPointer);
const MemberPointerType *destTy =
E->getType()->castAs<MemberPointerType>();
if (destTy->isMemberDataPointer()) {
llvm::Value *dst;
if (isDerivedToBase)
dst = Builder.CreateNSWSub(src, adj, "adj");
else
dst = Builder.CreateNSWAdd(src, adj, "adj");
llvm::Value *null = llvm::Constant::getAllOnesValue(src->getType());
llvm::Value *isNull = Builder.CreateICmpEQ(src, null, "memptr.isnull");
return Builder.CreateSelect(isNull, src, dst);
}
if (UseARMMethodPtrABI) {
uint64_t offset = cast<llvm::ConstantInt>(adj)->getZExtValue();
offset <<= 1;
adj = llvm::ConstantInt::get(adj->getType(), offset);
}
llvm::Value *srcAdj = Builder.CreateExtractValue(src, 1, "src.adj");
llvm::Value *dstAdj;
if (isDerivedToBase)
dstAdj = Builder.CreateNSWSub(srcAdj, adj, "adj");
else
dstAdj = Builder.CreateNSWAdd(srcAdj, adj, "adj");
return Builder.CreateInsertValue(src, dstAdj, 1);
}
llvm::Constant *
ItaniumCXXABI::EmitMemberPointerConversion(const CastExpr *E,
llvm::Constant *src) {
assert(E->getCastKind() == CK_DerivedToBaseMemberPointer ||
E->getCastKind() == CK_BaseToDerivedMemberPointer ||
E->getCastKind() == CK_ReinterpretMemberPointer);
if (E->getCastKind() == CK_ReinterpretMemberPointer) return src;
llvm::Constant *adj = getMemberPointerAdjustment(E);
if (!adj) return src;
bool isDerivedToBase = (E->getCastKind() == CK_DerivedToBaseMemberPointer);
const MemberPointerType *destTy =
E->getType()->castAs<MemberPointerType>();
if (destTy->isMemberDataPointer()) {
if (src->isAllOnesValue()) return src;
if (isDerivedToBase)
return llvm::ConstantExpr::getNSWSub(src, adj);
else
return llvm::ConstantExpr::getNSWAdd(src, adj);
}
if (UseARMMethodPtrABI) {
uint64_t offset = cast<llvm::ConstantInt>(adj)->getZExtValue();
offset <<= 1;
adj = llvm::ConstantInt::get(adj->getType(), offset);
}
llvm::Constant *srcAdj = llvm::ConstantExpr::getExtractValue(src, 1);
llvm::Constant *dstAdj;
if (isDerivedToBase)
dstAdj = llvm::ConstantExpr::getNSWSub(srcAdj, adj);
else
dstAdj = llvm::ConstantExpr::getNSWAdd(srcAdj, adj);
return llvm::ConstantExpr::getInsertValue(src, dstAdj, 1);
}
llvm::Constant *
ItaniumCXXABI::EmitNullMemberPointer(const MemberPointerType *MPT) {
if (MPT->isMemberDataPointer())
return llvm::ConstantInt::get(CGM.PtrDiffTy, -1ULL, true);
llvm::Constant *Zero = llvm::ConstantInt::get(CGM.PtrDiffTy, 0);
llvm::Constant *Values[2] = { Zero, Zero };
return llvm::ConstantStruct::getAnon(Values);
}
llvm::Constant *
ItaniumCXXABI::EmitMemberDataPointer(const MemberPointerType *MPT,
CharUnits offset) {
return llvm::ConstantInt::get(CGM.PtrDiffTy, offset.getQuantity());
}
llvm::Constant *
ItaniumCXXABI::EmitMemberFunctionPointer(const CXXMethodDecl *MD) {
return BuildMemberPointer(MD, CharUnits::Zero());
}
llvm::Constant *ItaniumCXXABI::BuildMemberPointer(const CXXMethodDecl *MD,
CharUnits ThisAdjustment) {
assert(MD->isInstance() && "Member function must not be static!");
MD = MD->getCanonicalDecl();
CodeGenTypes &Types = CGM.getTypes();
llvm::Constant *MemPtr[2];
if (MD->isVirtual()) {
uint64_t Index = CGM.getItaniumVTableContext().getMethodVTableIndex(MD);
const ASTContext &Context = getContext();
CharUnits PointerWidth =
Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
uint64_t VTableOffset = (Index * PointerWidth.getQuantity());
if (UseARMMethodPtrABI) {
MemPtr[0] = llvm::ConstantInt::get(CGM.PtrDiffTy, VTableOffset);
MemPtr[1] = llvm::ConstantInt::get(CGM.PtrDiffTy,
2 * ThisAdjustment.getQuantity() + 1);
} else {
MemPtr[0] = llvm::ConstantInt::get(CGM.PtrDiffTy, VTableOffset + 1);
MemPtr[1] = llvm::ConstantInt::get(CGM.PtrDiffTy,
ThisAdjustment.getQuantity());
}
} else {
const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
llvm::Type *Ty;
if (Types.isFuncTypeConvertible(FPT)) {
Ty = Types.GetFunctionType(Types.arrangeCXXMethodDeclaration(MD));
} else {
Ty = CGM.PtrDiffTy;
}
llvm::Constant *addr = CGM.GetAddrOfFunction(MD, Ty);
MemPtr[0] = llvm::ConstantExpr::getPtrToInt(addr, CGM.PtrDiffTy);
MemPtr[1] = llvm::ConstantInt::get(CGM.PtrDiffTy,
(UseARMMethodPtrABI ? 2 : 1) *
ThisAdjustment.getQuantity());
}
return llvm::ConstantStruct::getAnon(MemPtr);
}
llvm::Constant *ItaniumCXXABI::EmitMemberPointer(const APValue &MP,
QualType MPType) {
const MemberPointerType *MPT = MPType->castAs<MemberPointerType>();
const ValueDecl *MPD = MP.getMemberPointerDecl();
if (!MPD)
return EmitNullMemberPointer(MPT);
CharUnits ThisAdjustment = getMemberPointerPathAdjustment(MP);
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MPD))
return BuildMemberPointer(MD, ThisAdjustment);
CharUnits FieldOffset =
getContext().toCharUnitsFromBits(getContext().getFieldOffset(MPD));
return EmitMemberDataPointer(MPT, ThisAdjustment + FieldOffset);
}
llvm::Value *
ItaniumCXXABI::EmitMemberPointerComparison(CodeGenFunction &CGF,
llvm::Value *L,
llvm::Value *R,
const MemberPointerType *MPT,
bool Inequality) {
CGBuilderTy &Builder = CGF.Builder;
llvm::ICmpInst::Predicate Eq;
llvm::Instruction::BinaryOps And, Or;
if (Inequality) {
Eq = llvm::ICmpInst::ICMP_NE;
And = llvm::Instruction::Or;
Or = llvm::Instruction::And;
} else {
Eq = llvm::ICmpInst::ICMP_EQ;
And = llvm::Instruction::And;
Or = llvm::Instruction::Or;
}
if (MPT->isMemberDataPointer())
return Builder.CreateICmp(Eq, L, R);
llvm::Value *LPtr = Builder.CreateExtractValue(L, 0, "lhs.memptr.ptr");
llvm::Value *RPtr = Builder.CreateExtractValue(R, 0, "rhs.memptr.ptr");
llvm::Value *PtrEq = Builder.CreateICmp(Eq, LPtr, RPtr, "cmp.ptr");
llvm::Value *Zero = llvm::Constant::getNullValue(LPtr->getType());
llvm::Value *EqZero = Builder.CreateICmp(Eq, LPtr, Zero, "cmp.ptr.null");
llvm::Value *LAdj = Builder.CreateExtractValue(L, 1, "lhs.memptr.adj");
llvm::Value *RAdj = Builder.CreateExtractValue(R, 1, "rhs.memptr.adj");
llvm::Value *AdjEq = Builder.CreateICmp(Eq, LAdj, RAdj, "cmp.adj");
if (UseARMMethodPtrABI) {
llvm::Value *One = llvm::ConstantInt::get(LPtr->getType(), 1);
llvm::Value *OrAdj = Builder.CreateOr(LAdj, RAdj, "or.adj");
llvm::Value *OrAdjAnd1 = Builder.CreateAnd(OrAdj, One);
llvm::Value *OrAdjAnd1EqZero = Builder.CreateICmp(Eq, OrAdjAnd1, Zero,
"cmp.or.adj");
EqZero = Builder.CreateBinOp(And, EqZero, OrAdjAnd1EqZero);
}
llvm::Value *Result = Builder.CreateBinOp(Or, EqZero, AdjEq);
Result = Builder.CreateBinOp(And, PtrEq, Result,
Inequality ? "memptr.ne" : "memptr.eq");
return Result;
}
llvm::Value *
ItaniumCXXABI::EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
llvm::Value *MemPtr,
const MemberPointerType *MPT) {
CGBuilderTy &Builder = CGF.Builder;
if (MPT->isMemberDataPointer()) {
assert(MemPtr->getType() == CGM.PtrDiffTy);
llvm::Value *NegativeOne =
llvm::Constant::getAllOnesValue(MemPtr->getType());
return Builder.CreateICmpNE(MemPtr, NegativeOne, "memptr.tobool");
}
llvm::Value *Ptr = Builder.CreateExtractValue(MemPtr, 0, "memptr.ptr");
llvm::Constant *Zero = llvm::ConstantInt::get(Ptr->getType(), 0);
llvm::Value *Result = Builder.CreateICmpNE(Ptr, Zero, "memptr.tobool");
if (UseARMMethodPtrABI) {
llvm::Constant *One = llvm::ConstantInt::get(Ptr->getType(), 1);
llvm::Value *Adj = Builder.CreateExtractValue(MemPtr, 1, "memptr.adj");
llvm::Value *VirtualBit = Builder.CreateAnd(Adj, One, "memptr.virtualbit");
llvm::Value *IsVirtual = Builder.CreateICmpNE(VirtualBit, Zero,
"memptr.isvirtual");
Result = Builder.CreateOr(Result, IsVirtual);
}
return Result;
}
bool ItaniumCXXABI::classifyReturnType(CGFunctionInfo &FI) const {
const CXXRecordDecl *RD = FI.getReturnType()->getAsCXXRecordDecl();
if (!RD)
return false;
if (RD->hasNonTrivialDestructor() || RD->hasNonTrivialCopyConstructor()) {
auto Align = CGM.getContext().getTypeAlignInChars(FI.getReturnType());
FI.getReturnInfo() = ABIArgInfo::getIndirect(Align, false);
return true;
}
return false;
}
bool ItaniumCXXABI::isZeroInitializable(const MemberPointerType *MPT) {
return MPT->isMemberFunctionPointer();
}
void ItaniumCXXABI::emitVirtualObjectDelete(CodeGenFunction &CGF,
const CXXDeleteExpr *DE,
Address Ptr,
QualType ElementType,
const CXXDestructorDecl *Dtor) {
bool UseGlobalDelete = DE->isGlobalDelete();
if (UseGlobalDelete) {
auto *ClassDecl =
cast<CXXRecordDecl>(ElementType->getAs<RecordType>()->getDecl());
llvm::Value *VTable =
CGF.GetVTablePtr(Ptr, CGF.IntPtrTy->getPointerTo(), ClassDecl);
llvm::Value *OffsetPtr = CGF.Builder.CreateConstInBoundsGEP1_64(
VTable, -2, "complete-offset.ptr");
llvm::Value *Offset =
CGF.Builder.CreateAlignedLoad(OffsetPtr, CGF.getPointerAlign());
llvm::Value *CompletePtr =
CGF.Builder.CreateBitCast(Ptr.getPointer(), CGF.Int8PtrTy);
CompletePtr = CGF.Builder.CreateInBoundsGEP(CompletePtr, Offset);
CGF.pushCallObjectDeleteCleanup(DE->getOperatorDelete(), CompletePtr,
ElementType);
}
CXXDtorType DtorType = UseGlobalDelete ? Dtor_Complete : Dtor_Deleting;
EmitVirtualDestructorCall(CGF, Dtor, DtorType, Ptr, nullptr);
if (UseGlobalDelete)
CGF.PopCleanupBlock();
}
void ItaniumCXXABI::emitRethrow(CodeGenFunction &CGF, bool isNoReturn) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, false);
llvm::Constant *Fn = CGM.CreateRuntimeFunction(FTy, "__cxa_rethrow");
if (isNoReturn)
CGF.EmitNoreturnRuntimeCallOrInvoke(Fn, None);
else
CGF.EmitRuntimeCallOrInvoke(Fn);
}
static llvm::Constant *getAllocateExceptionFn(CodeGenModule &CGM) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.Int8PtrTy, CGM.SizeTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_allocate_exception");
}
static llvm::Constant *getThrowFn(CodeGenModule &CGM) {
llvm::Type *Args[3] = { CGM.Int8PtrTy, CGM.Int8PtrTy, CGM.Int8PtrTy };
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, Args, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_throw");
}
void ItaniumCXXABI::emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) {
QualType ThrowType = E->getSubExpr()->getType();
llvm::Type *SizeTy = CGF.ConvertType(getContext().getSizeType());
uint64_t TypeSize = getContext().getTypeSizeInChars(ThrowType).getQuantity();
llvm::Constant *AllocExceptionFn = getAllocateExceptionFn(CGM);
llvm::CallInst *ExceptionPtr = CGF.EmitNounwindRuntimeCall(
AllocExceptionFn, llvm::ConstantInt::get(SizeTy, TypeSize), "exception");
CharUnits ExnAlign = getAlignmentOfExnObject();
CGF.EmitAnyExprToExn(E->getSubExpr(), Address(ExceptionPtr, ExnAlign));
llvm::Constant *TypeInfo = CGM.GetAddrOfRTTIDescriptor(ThrowType,
true);
llvm::Constant *Dtor = nullptr;
if (const RecordType *RecordTy = ThrowType->getAs<RecordType>()) {
CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordTy->getDecl());
if (!Record->hasTrivialDestructor()) {
CXXDestructorDecl *DtorD = Record->getDestructor();
Dtor = CGM.getAddrOfCXXStructor(DtorD, StructorType::Complete);
Dtor = llvm::ConstantExpr::getBitCast(Dtor, CGM.Int8PtrTy);
}
}
if (!Dtor) Dtor = llvm::Constant::getNullValue(CGM.Int8PtrTy);
llvm::Value *args[] = { ExceptionPtr, TypeInfo, Dtor };
CGF.EmitNoreturnRuntimeCallOrInvoke(getThrowFn(CGM), args);
}
static llvm::Constant *getItaniumDynamicCastFn(CodeGenFunction &CGF) {
llvm::Type *Int8PtrTy = CGF.Int8PtrTy;
llvm::Type *PtrDiffTy =
CGF.ConvertType(CGF.getContext().getPointerDiffType());
llvm::Type *Args[4] = { Int8PtrTy, Int8PtrTy, Int8PtrTy, PtrDiffTy };
llvm::FunctionType *FTy = llvm::FunctionType::get(Int8PtrTy, Args, false);
llvm::Attribute::AttrKind FuncAttrs[] = { llvm::Attribute::NoUnwind,
llvm::Attribute::ReadOnly };
llvm::AttributeSet Attrs = llvm::AttributeSet::get(
CGF.getLLVMContext(), llvm::AttributeSet::FunctionIndex, FuncAttrs);
return CGF.CGM.CreateRuntimeFunction(FTy, "__dynamic_cast", Attrs);
}
static llvm::Constant *getBadCastFn(CodeGenFunction &CGF) {
llvm::FunctionType *FTy = llvm::FunctionType::get(CGF.VoidTy, false);
return CGF.CGM.CreateRuntimeFunction(FTy, "__cxa_bad_cast");
}
static CharUnits computeOffsetHint(ASTContext &Context,
const CXXRecordDecl *Src,
const CXXRecordDecl *Dst) {
CXXBasePaths Paths(true, true,
false);
if (!Dst->isDerivedFrom(Src, Paths))
return CharUnits::fromQuantity(-2ULL);
unsigned NumPublicPaths = 0;
CharUnits Offset;
for (const CXXBasePath &Path : Paths) {
if (Path.Access != AS_public) continue;
++NumPublicPaths;
for (const CXXBasePathElement &PathElement : Path) {
if (PathElement.Base->isVirtual())
return CharUnits::fromQuantity(-1ULL);
if (NumPublicPaths > 1) continue;
const ASTRecordLayout &L = Context.getASTRecordLayout(PathElement.Class);
Offset += L.getBaseClassOffset(
PathElement.Base->getType()->getAsCXXRecordDecl());
}
}
if (NumPublicPaths == 0)
return CharUnits::fromQuantity(-2ULL);
if (NumPublicPaths > 1)
return CharUnits::fromQuantity(-3ULL);
return Offset;
}
static llvm::Constant *getBadTypeidFn(CodeGenFunction &CGF) {
llvm::FunctionType *FTy = llvm::FunctionType::get(CGF.VoidTy, false);
return CGF.CGM.CreateRuntimeFunction(FTy, "__cxa_bad_typeid");
}
bool ItaniumCXXABI::shouldTypeidBeNullChecked(bool IsDeref,
QualType SrcRecordTy) {
return IsDeref;
}
void ItaniumCXXABI::EmitBadTypeidCall(CodeGenFunction &CGF) {
llvm::Value *Fn = getBadTypeidFn(CGF);
CGF.EmitRuntimeCallOrInvoke(Fn).setDoesNotReturn();
CGF.Builder.CreateUnreachable();
}
llvm::Value *ItaniumCXXABI::EmitTypeid(CodeGenFunction &CGF,
QualType SrcRecordTy,
Address ThisPtr,
llvm::Type *StdTypeInfoPtrTy) {
auto *ClassDecl =
cast<CXXRecordDecl>(SrcRecordTy->getAs<RecordType>()->getDecl());
llvm::Value *Value =
CGF.GetVTablePtr(ThisPtr, StdTypeInfoPtrTy->getPointerTo(), ClassDecl);
Value = CGF.Builder.CreateConstInBoundsGEP1_64(Value, -1ULL);
return CGF.Builder.CreateAlignedLoad(Value, CGF.getPointerAlign());
}
bool ItaniumCXXABI::shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
QualType SrcRecordTy) {
return SrcIsPtr;
}
llvm::Value *ItaniumCXXABI::EmitDynamicCastCall(
CodeGenFunction &CGF, Address ThisAddr, QualType SrcRecordTy,
QualType DestTy, QualType DestRecordTy, llvm::BasicBlock *CastEnd) {
llvm::Type *PtrDiffLTy =
CGF.ConvertType(CGF.getContext().getPointerDiffType());
llvm::Type *DestLTy = CGF.ConvertType(DestTy);
llvm::Value *SrcRTTI =
CGF.CGM.GetAddrOfRTTIDescriptor(SrcRecordTy.getUnqualifiedType());
llvm::Value *DestRTTI =
CGF.CGM.GetAddrOfRTTIDescriptor(DestRecordTy.getUnqualifiedType());
const CXXRecordDecl *SrcDecl = SrcRecordTy->getAsCXXRecordDecl();
const CXXRecordDecl *DestDecl = DestRecordTy->getAsCXXRecordDecl();
llvm::Value *OffsetHint = llvm::ConstantInt::get(
PtrDiffLTy,
computeOffsetHint(CGF.getContext(), SrcDecl, DestDecl).getQuantity());
llvm::Value *Value = ThisAddr.getPointer();
Value = CGF.EmitCastToVoidPtr(Value);
llvm::Value *args[] = {Value, SrcRTTI, DestRTTI, OffsetHint};
Value = CGF.EmitNounwindRuntimeCall(getItaniumDynamicCastFn(CGF), args);
Value = CGF.Builder.CreateBitCast(Value, DestLTy);
if (DestTy->isReferenceType()) {
llvm::BasicBlock *BadCastBlock =
CGF.createBasicBlock("dynamic_cast.bad_cast");
llvm::Value *IsNull = CGF.Builder.CreateIsNull(Value);
CGF.Builder.CreateCondBr(IsNull, BadCastBlock, CastEnd);
CGF.EmitBlock(BadCastBlock);
EmitBadCastCall(CGF);
}
return Value;
}
llvm::Value *ItaniumCXXABI::EmitDynamicCastToVoid(CodeGenFunction &CGF,
Address ThisAddr,
QualType SrcRecordTy,
QualType DestTy) {
llvm::Type *PtrDiffLTy =
CGF.ConvertType(CGF.getContext().getPointerDiffType());
llvm::Type *DestLTy = CGF.ConvertType(DestTy);
auto *ClassDecl =
cast<CXXRecordDecl>(SrcRecordTy->getAs<RecordType>()->getDecl());
llvm::Value *VTable = CGF.GetVTablePtr(ThisAddr, PtrDiffLTy->getPointerTo(),
ClassDecl);
llvm::Value *OffsetToTop =
CGF.Builder.CreateConstInBoundsGEP1_64(VTable, -2ULL);
OffsetToTop =
CGF.Builder.CreateAlignedLoad(OffsetToTop, CGF.getPointerAlign(),
"offset.to.top");
llvm::Value *Value = ThisAddr.getPointer();
Value = CGF.EmitCastToVoidPtr(Value);
Value = CGF.Builder.CreateInBoundsGEP(Value, OffsetToTop);
return CGF.Builder.CreateBitCast(Value, DestLTy);
}
bool ItaniumCXXABI::EmitBadCastCall(CodeGenFunction &CGF) {
llvm::Value *Fn = getBadCastFn(CGF);
CGF.EmitRuntimeCallOrInvoke(Fn).setDoesNotReturn();
CGF.Builder.CreateUnreachable();
return true;
}
llvm::Value *
ItaniumCXXABI::GetVirtualBaseClassOffset(CodeGenFunction &CGF,
Address This,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl) {
llvm::Value *VTablePtr = CGF.GetVTablePtr(This, CGM.Int8PtrTy, ClassDecl);
CharUnits VBaseOffsetOffset =
CGM.getItaniumVTableContext().getVirtualBaseOffsetOffset(ClassDecl,
BaseClassDecl);
llvm::Value *VBaseOffsetPtr =
CGF.Builder.CreateConstGEP1_64(VTablePtr, VBaseOffsetOffset.getQuantity(),
"vbase.offset.ptr");
VBaseOffsetPtr = CGF.Builder.CreateBitCast(VBaseOffsetPtr,
CGM.PtrDiffTy->getPointerTo());
llvm::Value *VBaseOffset =
CGF.Builder.CreateAlignedLoad(VBaseOffsetPtr, CGF.getPointerAlign(),
"vbase.offset");
return VBaseOffset;
}
void ItaniumCXXABI::EmitCXXConstructors(const CXXConstructorDecl *D) {
assert(CGM.getTarget().getCXXABI().hasConstructorVariants());
CGM.EmitGlobal(GlobalDecl(D, Ctor_Base));
if (!D->getParent()->isAbstract()) {
CGM.EmitGlobal(GlobalDecl(D, Ctor_Complete));
}
}
void
ItaniumCXXABI::buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
SmallVectorImpl<CanQualType> &ArgTys) {
ASTContext &Context = getContext();
if (T == StructorType::Base && MD->getParent()->getNumVBases() != 0)
ArgTys.insert(ArgTys.begin() + 1,
Context.getPointerType(Context.VoidPtrTy));
}
void ItaniumCXXABI::EmitCXXDestructors(const CXXDestructorDecl *D) {
CGM.EmitGlobal(GlobalDecl(D, Dtor_Base));
CGM.EmitGlobal(GlobalDecl(D, Dtor_Complete));
if (D->isVirtual())
CGM.EmitGlobal(GlobalDecl(D, Dtor_Deleting));
}
void ItaniumCXXABI::addImplicitStructorParams(CodeGenFunction &CGF,
QualType &ResTy,
FunctionArgList &Params) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(CGF.CurGD.getDecl());
assert(isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD));
if (NeedsVTTParameter(CGF.CurGD)) {
ASTContext &Context = getContext();
QualType T = Context.getPointerType(Context.VoidPtrTy);
ImplicitParamDecl *VTTDecl
= ImplicitParamDecl::Create(Context, nullptr, MD->getLocation(),
&Context.Idents.get("vtt"), T);
Params.insert(Params.begin() + 1, VTTDecl);
getStructorImplicitParamDecl(CGF) = VTTDecl;
}
}
void ItaniumCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
EmitThisParam(CGF);
if (getStructorImplicitParamDecl(CGF)) {
getStructorImplicitParamValue(CGF) = CGF.Builder.CreateLoad(
CGF.GetAddrOfLocalVar(getStructorImplicitParamDecl(CGF)), "vtt");
}
if (HasThisReturn(CGF.CurGD))
CGF.Builder.CreateStore(getThisValue(CGF), CGF.ReturnValue);
}
unsigned ItaniumCXXABI::addImplicitConstructorArgs(
CodeGenFunction &CGF, const CXXConstructorDecl *D, CXXCtorType Type,
bool ForVirtualBase, bool Delegating, CallArgList &Args) {
if (!NeedsVTTParameter(GlobalDecl(D, Type)))
return 0;
llvm::Value *VTT =
CGF.GetVTTParameter(GlobalDecl(D, Type), ForVirtualBase, Delegating);
QualType VTTTy = getContext().getPointerType(getContext().VoidPtrTy);
Args.insert(Args.begin() + 1,
CallArg(RValue::get(VTT), VTTTy, false));
return 1; }
void ItaniumCXXABI::EmitDestructorCall(CodeGenFunction &CGF,
const CXXDestructorDecl *DD,
CXXDtorType Type, bool ForVirtualBase,
bool Delegating, Address This) {
GlobalDecl GD(DD, Type);
llvm::Value *VTT = CGF.GetVTTParameter(GD, ForVirtualBase, Delegating);
QualType VTTTy = getContext().getPointerType(getContext().VoidPtrTy);
llvm::Value *Callee = nullptr;
if (getContext().getLangOpts().AppleKext)
Callee = CGF.BuildAppleKextVirtualDestructorCall(DD, Type, DD->getParent());
if (!Callee)
Callee = CGM.getAddrOfCXXStructor(DD, getFromDtorType(Type));
CGF.EmitCXXMemberOrOperatorCall(DD, Callee, ReturnValueSlot(),
This.getPointer(), VTT, VTTTy, nullptr);
}
void ItaniumCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
const CXXRecordDecl *RD) {
llvm::GlobalVariable *VTable = getAddrOfVTable(RD, CharUnits());
if (VTable->hasInitializer())
return;
ItaniumVTableContext &VTContext = CGM.getItaniumVTableContext();
const VTableLayout &VTLayout = VTContext.getVTableLayout(RD);
llvm::GlobalVariable::LinkageTypes Linkage = CGM.getVTableLinkage(RD);
llvm::Constant *RTTI =
CGM.GetAddrOfRTTIDescriptor(CGM.getContext().getTagDeclType(RD));
llvm::Constant *Init = CGVT.CreateVTableInitializer(
RD, VTLayout.vtable_component_begin(), VTLayout.getNumVTableComponents(),
VTLayout.vtable_thunk_begin(), VTLayout.getNumVTableThunks(), RTTI);
VTable->setInitializer(Init);
VTable->setLinkage(Linkage);
if (CGM.supportsCOMDAT() && VTable->isWeakForLinker())
VTable->setComdat(CGM.getModule().getOrInsertComdat(VTable->getName()));
CGM.setGlobalVisibility(VTable, RD);
unsigned PAlign = CGM.getTarget().getPointerAlign(0);
VTable->setAlignment(getContext().toCharUnitsFromBits(PAlign).getQuantity());
const DeclContext *DC = RD->getDeclContext();
if (RD->getIdentifier() &&
RD->getIdentifier()->isStr("__fundamental_type_info") &&
isa<NamespaceDecl>(DC) && cast<NamespaceDecl>(DC)->getIdentifier() &&
cast<NamespaceDecl>(DC)->getIdentifier()->isStr("__cxxabiv1") &&
DC->getParent()->isTranslationUnit())
EmitFundamentalRTTIDescriptors();
if (!VTable->isDeclarationForLinker())
CGM.EmitVTableBitSetEntries(VTable, VTLayout);
}
bool ItaniumCXXABI::isVirtualOffsetNeededForVTableField(
CodeGenFunction &CGF, CodeGenFunction::VPtr Vptr) {
if (Vptr.NearestVBase == nullptr)
return false;
return NeedsVTTParameter(CGF.CurGD);
}
llvm::Value *ItaniumCXXABI::getVTableAddressPointInStructor(
CodeGenFunction &CGF, const CXXRecordDecl *VTableClass, BaseSubobject Base,
const CXXRecordDecl *NearestVBase) {
if ((Base.getBase()->getNumVBases() || NearestVBase != nullptr) &&
NeedsVTTParameter(CGF.CurGD)) {
return getVTableAddressPointInStructorWithVTT(CGF, VTableClass, Base,
NearestVBase);
}
return getVTableAddressPoint(Base, VTableClass);
}
llvm::Constant *
ItaniumCXXABI::getVTableAddressPoint(BaseSubobject Base,
const CXXRecordDecl *VTableClass) {
llvm::GlobalValue *VTable = getAddrOfVTable(VTableClass, CharUnits());
uint64_t AddressPoint = CGM.getItaniumVTableContext()
.getVTableLayout(VTableClass)
.getAddressPoint(Base);
llvm::Value *Indices[] = {
llvm::ConstantInt::get(CGM.Int64Ty, 0),
llvm::ConstantInt::get(CGM.Int64Ty, AddressPoint)
};
return llvm::ConstantExpr::getInBoundsGetElementPtr(VTable->getValueType(),
VTable, Indices);
}
llvm::Value *ItaniumCXXABI::getVTableAddressPointInStructorWithVTT(
CodeGenFunction &CGF, const CXXRecordDecl *VTableClass, BaseSubobject Base,
const CXXRecordDecl *NearestVBase) {
assert((Base.getBase()->getNumVBases() || NearestVBase != nullptr) &&
NeedsVTTParameter(CGF.CurGD) && "This class doesn't have VTT");
uint64_t VirtualPointerIndex =
CGM.getVTables().getSecondaryVirtualPointerIndex(VTableClass, Base);
llvm::Value *VTT = CGF.LoadCXXVTT();
if (VirtualPointerIndex)
VTT = CGF.Builder.CreateConstInBoundsGEP1_64(VTT, VirtualPointerIndex);
return CGF.Builder.CreateAlignedLoad(VTT, CGF.getPointerAlign());
}
llvm::Constant *ItaniumCXXABI::getVTableAddressPointForConstExpr(
BaseSubobject Base, const CXXRecordDecl *VTableClass) {
return getVTableAddressPoint(Base, VTableClass);
}
llvm::GlobalVariable *ItaniumCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
CharUnits VPtrOffset) {
assert(VPtrOffset.isZero() && "Itanium ABI only supports zero vptr offsets");
llvm::GlobalVariable *&VTable = VTables[RD];
if (VTable)
return VTable;
CGM.addDeferredVTable(RD);
SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
getMangleContext().mangleCXXVTable(RD, Out);
ItaniumVTableContext &VTContext = CGM.getItaniumVTableContext();
llvm::ArrayType *ArrayType = llvm::ArrayType::get(
CGM.Int8PtrTy, VTContext.getVTableLayout(RD).getNumVTableComponents());
VTable = CGM.CreateOrReplaceCXXRuntimeVariable(
Name, ArrayType, llvm::GlobalValue::ExternalLinkage);
VTable->setUnnamedAddr(true);
if (RD->hasAttr<DLLImportAttr>())
VTable->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
else if (RD->hasAttr<DLLExportAttr>())
VTable->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
return VTable;
}
llvm::Value *ItaniumCXXABI::getVirtualFunctionPointer(CodeGenFunction &CGF,
GlobalDecl GD,
Address This,
llvm::Type *Ty,
SourceLocation Loc) {
GD = GD.getCanonicalDecl();
Ty = Ty->getPointerTo()->getPointerTo();
auto *MethodDecl = cast<CXXMethodDecl>(GD.getDecl());
llvm::Value *VTable = CGF.GetVTablePtr(This, Ty, MethodDecl->getParent());
if (CGF.SanOpts.has(SanitizerKind::CFIVCall))
CGF.EmitVTablePtrCheckForCall(MethodDecl, VTable,
CodeGenFunction::CFITCK_VCall, Loc);
uint64_t VTableIndex = CGM.getItaniumVTableContext().getMethodVTableIndex(GD);
llvm::Value *VFuncPtr =
CGF.Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfn");
return CGF.Builder.CreateAlignedLoad(VFuncPtr, CGF.getPointerAlign());
}
llvm::Value *ItaniumCXXABI::EmitVirtualDestructorCall(
CodeGenFunction &CGF, const CXXDestructorDecl *Dtor, CXXDtorType DtorType,
Address This, const CXXMemberCallExpr *CE) {
assert(CE == nullptr || CE->arg_begin() == CE->arg_end());
assert(DtorType == Dtor_Deleting || DtorType == Dtor_Complete);
const CGFunctionInfo *FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
Dtor, getFromDtorType(DtorType));
llvm::Type *Ty = CGF.CGM.getTypes().GetFunctionType(*FInfo);
llvm::Value *Callee =
getVirtualFunctionPointer(CGF, GlobalDecl(Dtor, DtorType), This, Ty,
CE ? CE->getLocStart() : SourceLocation());
CGF.EmitCXXMemberOrOperatorCall(Dtor, Callee, ReturnValueSlot(),
This.getPointer(), nullptr,
QualType(), CE);
return nullptr;
}
void ItaniumCXXABI::emitVirtualInheritanceTables(const CXXRecordDecl *RD) {
CodeGenVTables &VTables = CGM.getVTables();
llvm::GlobalVariable *VTT = VTables.GetAddrOfVTT(RD);
VTables.EmitVTTDefinition(VTT, CGM.getVTableLinkage(RD), RD);
}
bool ItaniumCXXABI::canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const {
if (CGM.getLangOpts().AppleKext)
return false;
return !hasAnyUsedVirtualInlineFunction(RD) && !isVTableHidden(RD);
}
static llvm::Value *performTypeAdjustment(CodeGenFunction &CGF,
Address InitialPtr,
int64_t NonVirtualAdjustment,
int64_t VirtualAdjustment,
bool IsReturnAdjustment) {
if (!NonVirtualAdjustment && !VirtualAdjustment)
return InitialPtr.getPointer();
Address V = CGF.Builder.CreateElementBitCast(InitialPtr, CGF.Int8Ty);
if (NonVirtualAdjustment && !IsReturnAdjustment) {
V = CGF.Builder.CreateConstInBoundsByteGEP(V,
CharUnits::fromQuantity(NonVirtualAdjustment));
}
llvm::Value *ResultPtr;
if (VirtualAdjustment) {
llvm::Type *PtrDiffTy =
CGF.ConvertType(CGF.getContext().getPointerDiffType());
Address VTablePtrPtr = CGF.Builder.CreateElementBitCast(V, CGF.Int8PtrTy);
llvm::Value *VTablePtr = CGF.Builder.CreateLoad(VTablePtrPtr);
llvm::Value *OffsetPtr =
CGF.Builder.CreateConstInBoundsGEP1_64(VTablePtr, VirtualAdjustment);
OffsetPtr = CGF.Builder.CreateBitCast(OffsetPtr, PtrDiffTy->getPointerTo());
llvm::Value *Offset =
CGF.Builder.CreateAlignedLoad(OffsetPtr, CGF.getPointerAlign());
ResultPtr = CGF.Builder.CreateInBoundsGEP(V.getPointer(), Offset);
} else {
ResultPtr = V.getPointer();
}
if (NonVirtualAdjustment && IsReturnAdjustment) {
ResultPtr = CGF.Builder.CreateConstInBoundsGEP1_64(ResultPtr,
NonVirtualAdjustment);
}
return CGF.Builder.CreateBitCast(ResultPtr, InitialPtr.getType());
}
llvm::Value *ItaniumCXXABI::performThisAdjustment(CodeGenFunction &CGF,
Address This,
const ThisAdjustment &TA) {
return performTypeAdjustment(CGF, This, TA.NonVirtual,
TA.Virtual.Itanium.VCallOffsetOffset,
false);
}
llvm::Value *
ItaniumCXXABI::performReturnAdjustment(CodeGenFunction &CGF, Address Ret,
const ReturnAdjustment &RA) {
return performTypeAdjustment(CGF, Ret, RA.NonVirtual,
RA.Virtual.Itanium.VBaseOffsetOffset,
true);
}
void ARMCXXABI::EmitReturnFromThunk(CodeGenFunction &CGF,
RValue RV, QualType ResultType) {
if (!isa<CXXDestructorDecl>(CGF.CurGD.getDecl()))
return ItaniumCXXABI::EmitReturnFromThunk(CGF, RV, ResultType);
llvm::Type *T = CGF.ReturnValue.getElementType();
RValue Undef = RValue::get(llvm::UndefValue::get(T));
return ItaniumCXXABI::EmitReturnFromThunk(CGF, Undef, ResultType);
}
CharUnits ItaniumCXXABI::getArrayCookieSizeImpl(QualType elementType) {
return std::max(CharUnits::fromQuantity(CGM.SizeSizeInBytes),
CGM.getContext().getTypeAlignInChars(elementType));
}
Address ItaniumCXXABI::InitializeArrayCookie(CodeGenFunction &CGF,
Address NewPtr,
llvm::Value *NumElements,
const CXXNewExpr *expr,
QualType ElementType) {
assert(requiresArrayCookie(expr));
unsigned AS = NewPtr.getAddressSpace();
ASTContext &Ctx = getContext();
CharUnits SizeSize = CGF.getSizeSize();
CharUnits CookieSize =
std::max(SizeSize, Ctx.getTypeAlignInChars(ElementType));
assert(CookieSize == getArrayCookieSizeImpl(ElementType));
Address CookiePtr = NewPtr;
CharUnits CookieOffset = CookieSize - SizeSize;
if (!CookieOffset.isZero())
CookiePtr = CGF.Builder.CreateConstInBoundsByteGEP(CookiePtr, CookieOffset);
Address NumElementsPtr =
CGF.Builder.CreateElementBitCast(CookiePtr, CGF.SizeTy);
llvm::Instruction *SI = CGF.Builder.CreateStore(NumElements, NumElementsPtr);
if (CGM.getLangOpts().Sanitize.has(SanitizerKind::Address) && AS == 0 &&
expr->getOperatorNew()->isReplaceableGlobalAllocationFunction()) {
CGM.getSanitizerMetadata()->disableSanitizerForInstruction(SI);
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, NumElementsPtr.getType(), false);
llvm::Constant *F =
CGM.CreateRuntimeFunction(FTy, "__asan_poison_cxx_array_cookie");
CGF.Builder.CreateCall(F, NumElementsPtr.getPointer());
}
return CGF.Builder.CreateConstInBoundsByteGEP(NewPtr, CookieSize);
}
llvm::Value *ItaniumCXXABI::readArrayCookieImpl(CodeGenFunction &CGF,
Address allocPtr,
CharUnits cookieSize) {
Address numElementsPtr = allocPtr;
CharUnits numElementsOffset = cookieSize - CGF.getSizeSize();
if (!numElementsOffset.isZero())
numElementsPtr =
CGF.Builder.CreateConstInBoundsByteGEP(numElementsPtr, numElementsOffset);
unsigned AS = allocPtr.getAddressSpace();
numElementsPtr = CGF.Builder.CreateElementBitCast(numElementsPtr, CGF.SizeTy);
if (!CGM.getLangOpts().Sanitize.has(SanitizerKind::Address) || AS != 0)
return CGF.Builder.CreateLoad(numElementsPtr);
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGF.SizeTy, CGF.SizeTy->getPointerTo(0), false);
llvm::Constant *F =
CGM.CreateRuntimeFunction(FTy, "__asan_load_cxx_array_cookie");
return CGF.Builder.CreateCall(F, numElementsPtr.getPointer());
}
CharUnits ARMCXXABI::getArrayCookieSizeImpl(QualType elementType) {
return std::max(CharUnits::fromQuantity(2 * CGM.SizeSizeInBytes),
CGM.getContext().getTypeAlignInChars(elementType));
}
Address ARMCXXABI::InitializeArrayCookie(CodeGenFunction &CGF,
Address newPtr,
llvm::Value *numElements,
const CXXNewExpr *expr,
QualType elementType) {
assert(requiresArrayCookie(expr));
Address cookie = newPtr;
cookie = CGF.Builder.CreateElementBitCast(cookie, CGF.SizeTy);
llvm::Value *elementSize = llvm::ConstantInt::get(CGF.SizeTy,
getContext().getTypeSizeInChars(elementType).getQuantity());
CGF.Builder.CreateStore(elementSize, cookie);
cookie = CGF.Builder.CreateConstInBoundsGEP(cookie, 1, CGF.getSizeSize());
CGF.Builder.CreateStore(numElements, cookie);
CharUnits cookieSize = ARMCXXABI::getArrayCookieSizeImpl(elementType);
return CGF.Builder.CreateConstInBoundsByteGEP(newPtr, cookieSize);
}
llvm::Value *ARMCXXABI::readArrayCookieImpl(CodeGenFunction &CGF,
Address allocPtr,
CharUnits cookieSize) {
Address numElementsPtr
= CGF.Builder.CreateConstInBoundsByteGEP(allocPtr, CGF.getSizeSize());
numElementsPtr = CGF.Builder.CreateElementBitCast(numElementsPtr, CGF.SizeTy);
return CGF.Builder.CreateLoad(numElementsPtr);
}
static llvm::Constant *getGuardAcquireFn(CodeGenModule &CGM,
llvm::PointerType *GuardPtrTy) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.getTypes().ConvertType(CGM.getContext().IntTy),
GuardPtrTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_guard_acquire",
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
llvm::Attribute::NoUnwind));
}
static llvm::Constant *getGuardReleaseFn(CodeGenModule &CGM,
llvm::PointerType *GuardPtrTy) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, GuardPtrTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_guard_release",
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
llvm::Attribute::NoUnwind));
}
static llvm::Constant *getGuardAbortFn(CodeGenModule &CGM,
llvm::PointerType *GuardPtrTy) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, GuardPtrTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_guard_abort",
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
llvm::Attribute::NoUnwind));
}
namespace {
struct CallGuardAbort final : EHScopeStack::Cleanup {
llvm::GlobalVariable *Guard;
CallGuardAbort(llvm::GlobalVariable *Guard) : Guard(Guard) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
CGF.EmitNounwindRuntimeCall(getGuardAbortFn(CGF.CGM, Guard->getType()),
Guard);
}
};
}
void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
const VarDecl &D,
llvm::GlobalVariable *var,
bool shouldPerformInit) {
CGBuilderTy &Builder = CGF.Builder;
bool threadsafe = getContext().getLangOpts().ThreadsafeStatics &&
D.isLocalVarDecl() && !D.getTLSKind();
bool useInt8GuardVariable = !threadsafe && var->hasInternalLinkage();
llvm::IntegerType *guardTy;
CharUnits guardAlignment;
if (useInt8GuardVariable) {
guardTy = CGF.Int8Ty;
guardAlignment = CharUnits::One();
} else {
if (UseARMGuardVarABI) {
guardTy = CGF.SizeTy;
guardAlignment = CGF.getSizeAlign();
} else {
guardTy = CGF.Int64Ty;
guardAlignment = CharUnits::fromQuantity(
CGM.getDataLayout().getABITypeAlignment(guardTy));
}
}
llvm::PointerType *guardPtrTy = guardTy->getPointerTo();
llvm::GlobalVariable *guard = CGM.getStaticLocalDeclGuardAddress(&D);
if (!guard) {
SmallString<256> guardName;
{
llvm::raw_svector_ostream out(guardName);
getMangleContext().mangleStaticGuardVariable(&D, out);
}
guard = new llvm::GlobalVariable(CGM.getModule(), guardTy,
false, var->getLinkage(),
llvm::ConstantInt::get(guardTy, 0),
guardName.str());
guard->setVisibility(var->getVisibility());
guard->setThreadLocalMode(var->getThreadLocalMode());
guard->setAlignment(guardAlignment.getQuantity());
llvm::Comdat *C = var->getComdat();
if (!D.isLocalVarDecl() && C &&
CGM.getTarget().getTriple().isOSBinFormatELF()) {
guard->setComdat(C);
CGF.CurFn->setComdat(C);
} else if (CGM.supportsCOMDAT() && guard->isWeakForLinker()) {
guard->setComdat(CGM.getModule().getOrInsertComdat(guard->getName()));
}
CGM.setStaticLocalDeclGuardAddress(&D, guard);
}
Address guardAddr = Address(guard, guardAlignment);
llvm::LoadInst *LI =
Builder.CreateLoad(Builder.CreateElementBitCast(guardAddr, CGM.Int8Ty));
if (threadsafe)
LI->setAtomic(llvm::Acquire);
llvm::Value *V =
(UseARMGuardVarABI && !useInt8GuardVariable)
? Builder.CreateAnd(LI, llvm::ConstantInt::get(CGM.Int8Ty, 1))
: LI;
llvm::Value *isInitialized = Builder.CreateIsNull(V, "guard.uninitialized");
llvm::BasicBlock *InitCheckBlock = CGF.createBasicBlock("init.check");
llvm::BasicBlock *EndBlock = CGF.createBasicBlock("init.end");
Builder.CreateCondBr(isInitialized, InitCheckBlock, EndBlock);
CGF.EmitBlock(InitCheckBlock);
if (threadsafe) {
llvm::Value *V
= CGF.EmitNounwindRuntimeCall(getGuardAcquireFn(CGM, guardPtrTy), guard);
llvm::BasicBlock *InitBlock = CGF.createBasicBlock("init");
Builder.CreateCondBr(Builder.CreateIsNotNull(V, "tobool"),
InitBlock, EndBlock);
CGF.EHStack.pushCleanup<CallGuardAbort>(EHCleanup, guard);
CGF.EmitBlock(InitBlock);
}
CGF.EmitCXXGlobalVarDeclInit(D, var, shouldPerformInit);
if (threadsafe) {
CGF.PopCleanupBlock();
CGF.EmitNounwindRuntimeCall(getGuardReleaseFn(CGM, guardPtrTy),
guardAddr.getPointer());
} else {
Builder.CreateStore(llvm::ConstantInt::get(guardTy, 1), guardAddr);
}
CGF.EmitBlock(EndBlock);
}
static void emitGlobalDtorWithCXAAtExit(CodeGenFunction &CGF,
llvm::Constant *dtor,
llvm::Constant *addr,
bool TLS) {
const char *Name = "__cxa_atexit";
if (TLS) {
const llvm::Triple &T = CGF.getTarget().getTriple();
Name = T.isOSDarwin() ? "_tlv_atexit" : "__cxa_thread_atexit";
}
llvm::Type *dtorTy =
llvm::FunctionType::get(CGF.VoidTy, CGF.Int8PtrTy, false)->getPointerTo();
llvm::Type *paramTys[] = { dtorTy, CGF.Int8PtrTy, CGF.Int8PtrTy };
llvm::FunctionType *atexitTy =
llvm::FunctionType::get(CGF.IntTy, paramTys, false);
llvm::Constant *atexit = CGF.CGM.CreateRuntimeFunction(atexitTy, Name);
if (llvm::Function *fn = dyn_cast<llvm::Function>(atexit))
fn->setDoesNotThrow();
llvm::Constant *handle =
CGF.CGM.CreateRuntimeVariable(CGF.Int8Ty, "__dso_handle");
llvm::Value *args[] = {
llvm::ConstantExpr::getBitCast(dtor, dtorTy),
llvm::ConstantExpr::getBitCast(addr, CGF.Int8PtrTy),
handle
};
CGF.EmitNounwindRuntimeCall(atexit, args);
}
void ItaniumCXXABI::registerGlobalDtor(CodeGenFunction &CGF,
const VarDecl &D,
llvm::Constant *dtor,
llvm::Constant *addr) {
if (CGM.getCodeGenOpts().CXAAtExit)
return emitGlobalDtorWithCXAAtExit(CGF, dtor, addr, D.getTLSKind());
if (D.getTLSKind())
CGM.ErrorUnsupported(&D, "non-trivial TLS destruction");
if (CGM.getLangOpts().AppleKext) {
return CGM.AddCXXDtorEntry(dtor, addr);
}
CGF.registerGlobalDtorWithAtExit(D, dtor, addr);
}
static bool isThreadWrapperReplaceable(const VarDecl *VD,
CodeGen::CodeGenModule &CGM) {
assert(!VD->isStaticLocal() && "static local VarDecls don't need wrappers!");
return VD->getTLSKind() == VarDecl::TLS_Dynamic &&
CGM.getTarget().getTriple().isOSDarwin();
}
static llvm::GlobalValue::LinkageTypes
getThreadLocalWrapperLinkage(const VarDecl *VD, CodeGen::CodeGenModule &CGM) {
llvm::GlobalValue::LinkageTypes VarLinkage =
CGM.getLLVMLinkageVarDefinition(VD, false);
if (llvm::GlobalValue::isLocalLinkage(VarLinkage))
return VarLinkage;
if (isThreadWrapperReplaceable(VD, CGM))
if (!llvm::GlobalVariable::isLinkOnceLinkage(VarLinkage) &&
!llvm::GlobalVariable::isWeakODRLinkage(VarLinkage))
return VarLinkage;
return llvm::GlobalValue::WeakODRLinkage;
}
llvm::Function *
ItaniumCXXABI::getOrCreateThreadLocalWrapper(const VarDecl *VD,
llvm::Value *Val) {
SmallString<256> WrapperName;
{
llvm::raw_svector_ostream Out(WrapperName);
getMangleContext().mangleItaniumThreadLocalWrapper(VD, Out);
}
if (llvm::Value *V = CGM.getModule().getNamedValue(WrapperName))
return cast<llvm::Function>(V);
QualType RetQT = VD->getType();
if (RetQT->isReferenceType())
RetQT = RetQT.getNonReferenceType();
const CGFunctionInfo &FI = CGM.getTypes().arrangeBuiltinFunctionDeclaration(
getContext().getPointerType(RetQT), FunctionArgList());
llvm::FunctionType *FnTy = CGM.getTypes().GetFunctionType(FI);
llvm::Function *Wrapper =
llvm::Function::Create(FnTy, getThreadLocalWrapperLinkage(VD, CGM),
WrapperName.str(), &CGM.getModule());
CGM.SetLLVMFunctionAttributes(nullptr, FI, Wrapper);
if (VD->hasDefinition())
CGM.SetLLVMFunctionAttributesForDefinition(nullptr, Wrapper);
if (!Wrapper->hasLocalLinkage() && !(isThreadWrapperReplaceable(VD, CGM) &&
!llvm::GlobalVariable::isLinkOnceLinkage(Wrapper->getLinkage()) &&
!llvm::GlobalVariable::isWeakODRLinkage(Wrapper->getLinkage())))
Wrapper->setVisibility(llvm::GlobalValue::HiddenVisibility);
if (isThreadWrapperReplaceable(VD, CGM)) {
Wrapper->setCallingConv(llvm::CallingConv::CXX_FAST_TLS);
Wrapper->addFnAttr(llvm::Attribute::NoUnwind);
}
return Wrapper;
}
void ItaniumCXXABI::EmitThreadLocalInitFuncs(
CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
ArrayRef<llvm::Function *> CXXThreadLocalInits,
ArrayRef<const VarDecl *> CXXThreadLocalInitVars) {
llvm::Function *InitFunc = nullptr;
if (!CXXThreadLocalInits.empty()) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, false);
const CGFunctionInfo &FI = CGM.getTypes().arrangeNullaryFunction();
InitFunc = CGM.CreateGlobalInitOrDestructFunction(FTy, "__tls_init", FI,
SourceLocation(),
true);
llvm::GlobalVariable *Guard = new llvm::GlobalVariable(
CGM.getModule(), CGM.Int8Ty, false,
llvm::GlobalVariable::InternalLinkage,
llvm::ConstantInt::get(CGM.Int8Ty, 0), "__tls_guard");
Guard->setThreadLocal(true);
CharUnits GuardAlign = CharUnits::One();
Guard->setAlignment(GuardAlign.getQuantity());
CodeGenFunction(CGM)
.GenerateCXXGlobalInitFunc(InitFunc, CXXThreadLocalInits,
Address(Guard, GuardAlign));
if (CGM.getTarget().getTriple().isOSDarwin()) {
InitFunc->setCallingConv(llvm::CallingConv::CXX_FAST_TLS);
InitFunc->addFnAttr(llvm::Attribute::NoUnwind);
}
}
for (const VarDecl *VD : CXXThreadLocals) {
llvm::GlobalVariable *Var =
cast<llvm::GlobalVariable>(CGM.GetGlobalValue(CGM.getMangledName(VD)));
if (isThreadWrapperReplaceable(VD, CGM) && !VD->hasDefinition())
continue;
SmallString<256> InitFnName;
{
llvm::raw_svector_ostream Out(InitFnName);
getMangleContext().mangleItaniumThreadLocalInit(VD, Out);
}
llvm::GlobalValue *Init = nullptr;
bool InitIsInitFunc = false;
if (VD->hasDefinition()) {
InitIsInitFunc = true;
if (InitFunc)
Init = llvm::GlobalAlias::create(Var->getLinkage(), InitFnName.str(),
InitFunc);
} else {
llvm::FunctionType *FnTy = llvm::FunctionType::get(CGM.VoidTy, false);
Init = llvm::Function::Create(
FnTy, llvm::GlobalVariable::ExternalWeakLinkage, InitFnName.str(),
&CGM.getModule());
const CGFunctionInfo &FI = CGM.getTypes().arrangeNullaryFunction();
CGM.SetLLVMFunctionAttributes(nullptr, FI, cast<llvm::Function>(Init));
}
if (Init)
Init->setVisibility(Var->getVisibility());
llvm::Function *Wrapper = getOrCreateThreadLocalWrapper(VD, Var);
llvm::LLVMContext &Context = CGM.getModule().getContext();
llvm::BasicBlock *Entry = llvm::BasicBlock::Create(Context, "", Wrapper);
CGBuilderTy Builder(CGM, Entry);
if (InitIsInitFunc) {
if (Init) {
llvm::CallInst *CallVal = Builder.CreateCall(Init);
if (isThreadWrapperReplaceable(VD, CGM))
CallVal->setCallingConv(llvm::CallingConv::CXX_FAST_TLS);
}
} else {
llvm::Value *Have = Builder.CreateIsNotNull(Init);
llvm::BasicBlock *InitBB = llvm::BasicBlock::Create(Context, "", Wrapper);
llvm::BasicBlock *ExitBB = llvm::BasicBlock::Create(Context, "", Wrapper);
Builder.CreateCondBr(Have, InitBB, ExitBB);
Builder.SetInsertPoint(InitBB);
Builder.CreateCall(Init);
Builder.CreateBr(ExitBB);
Builder.SetInsertPoint(ExitBB);
}
llvm::Value *Val = Var;
if (VD->getType()->isReferenceType()) {
CharUnits Align = CGM.getContext().getDeclAlign(VD);
Val = Builder.CreateAlignedLoad(Val, Align);
}
if (Val->getType() != Wrapper->getReturnType())
Val = Builder.CreatePointerBitCastOrAddrSpaceCast(
Val, Wrapper->getReturnType(), "");
Builder.CreateRet(Val);
}
}
LValue ItaniumCXXABI::EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF,
const VarDecl *VD,
QualType LValType) {
llvm::Value *Val = CGF.CGM.GetAddrOfGlobalVar(VD);
llvm::Function *Wrapper = getOrCreateThreadLocalWrapper(VD, Val);
llvm::CallInst *CallVal = CGF.Builder.CreateCall(Wrapper);
if (isThreadWrapperReplaceable(VD, CGF.CGM))
CallVal->setCallingConv(llvm::CallingConv::CXX_FAST_TLS);
LValue LV;
if (VD->getType()->isReferenceType())
LV = CGF.MakeNaturalAlignAddrLValue(CallVal, LValType);
else
LV = CGF.MakeAddrLValue(CallVal, LValType,
CGF.getContext().getDeclAlign(VD));
return LV;
}
bool ItaniumCXXABI::NeedsVTTParameter(GlobalDecl GD) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
if (!MD->getParent()->getNumVBases())
return false;
if (isa<CXXConstructorDecl>(MD) && GD.getCtorType() == Ctor_Base)
return true;
if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base)
return true;
return false;
}
namespace {
class ItaniumRTTIBuilder {
CodeGenModule &CGM; llvm::LLVMContext &VMContext;
const ItaniumCXXABI &CXXABI;
SmallVector<llvm::Constant *, 16> Fields;
llvm::GlobalVariable *
GetAddrOfTypeName(QualType Ty, llvm::GlobalVariable::LinkageTypes Linkage);
llvm::Constant *GetAddrOfExternalRTTIDescriptor(QualType Ty);
void BuildVTablePointer(const Type *Ty);
void BuildSIClassTypeInfo(const CXXRecordDecl *RD);
void BuildVMIClassTypeInfo(const CXXRecordDecl *RD);
void BuildPointerTypeInfo(QualType PointeeTy);
void BuildObjCObjectTypeInfo(const ObjCObjectType *Ty);
void BuildPointerToMemberTypeInfo(const MemberPointerType *Ty);
public:
ItaniumRTTIBuilder(const ItaniumCXXABI &ABI)
: CGM(ABI.CGM), VMContext(CGM.getModule().getContext()), CXXABI(ABI) {}
enum {
PTI_Const = 0x1,
PTI_Volatile = 0x2,
PTI_Restrict = 0x4,
PTI_Incomplete = 0x8,
PTI_ContainingClassIncomplete = 0x10
};
enum {
VMI_NonDiamondRepeat = 0x1,
VMI_DiamondShaped = 0x2
};
enum {
BCTI_Virtual = 0x1,
BCTI_Public = 0x2
};
llvm::Constant *BuildTypeInfo(QualType Ty, bool Force = false);
};
}
llvm::GlobalVariable *ItaniumRTTIBuilder::GetAddrOfTypeName(
QualType Ty, llvm::GlobalVariable::LinkageTypes Linkage) {
SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(Ty, Out);
llvm::Constant *Init = llvm::ConstantDataArray::getString(VMContext,
Name.substr(4));
llvm::GlobalVariable *GV =
CGM.CreateOrReplaceCXXRuntimeVariable(Name, Init->getType(), Linkage);
GV->setInitializer(Init);
return GV;
}
llvm::Constant *
ItaniumRTTIBuilder::GetAddrOfExternalRTTIDescriptor(QualType Ty) {
SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(Name);
if (!GV) {
GV = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8PtrTy,
true,
llvm::GlobalValue::ExternalLinkage, nullptr,
Name);
if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
const CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
if (RD->hasAttr<DLLImportAttr>())
GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
}
}
return llvm::ConstantExpr::getBitCast(GV, CGM.Int8PtrTy);
}
static bool TypeInfoIsInStandardLibrary(const BuiltinType *Ty) {
switch (Ty->getKind()) {
case BuiltinType::Void:
case BuiltinType::NullPtr:
case BuiltinType::Bool:
case BuiltinType::WChar_S:
case BuiltinType::WChar_U:
case BuiltinType::Char_U:
case BuiltinType::Char_S:
case BuiltinType::UChar:
case BuiltinType::SChar:
case BuiltinType::Short:
case BuiltinType::UShort:
case BuiltinType::Int:
case BuiltinType::UInt:
case BuiltinType::Long:
case BuiltinType::ULong:
case BuiltinType::LongLong:
case BuiltinType::ULongLong:
case BuiltinType::Half:
case BuiltinType::Float:
case BuiltinType::Double:
case BuiltinType::LongDouble:
case BuiltinType::Char16:
case BuiltinType::Char32:
case BuiltinType::Int128:
case BuiltinType::UInt128:
case BuiltinType::OCLImage1d:
case BuiltinType::OCLImage1dArray:
case BuiltinType::OCLImage1dBuffer:
case BuiltinType::OCLImage2d:
case BuiltinType::OCLImage2dArray:
case BuiltinType::OCLImage2dDepth:
case BuiltinType::OCLImage2dArrayDepth:
case BuiltinType::OCLImage2dMSAA:
case BuiltinType::OCLImage2dArrayMSAA:
case BuiltinType::OCLImage2dMSAADepth:
case BuiltinType::OCLImage2dArrayMSAADepth:
case BuiltinType::OCLImage3d:
case BuiltinType::OCLSampler:
case BuiltinType::OCLEvent:
case BuiltinType::OCLClkEvent:
case BuiltinType::OCLQueue:
case BuiltinType::OCLNDRange:
case BuiltinType::OCLReserveID:
return true;
case BuiltinType::Dependent:
#define BUILTIN_TYPE(Id, SingletonId)
#define PLACEHOLDER_TYPE(Id, SingletonId) \
case BuiltinType::Id:
#include "clang/AST/BuiltinTypes.def"
llvm_unreachable("asking for RRTI for a placeholder type!");
case BuiltinType::ObjCId:
case BuiltinType::ObjCClass:
case BuiltinType::ObjCSel:
llvm_unreachable("FIXME: Objective-C types are unsupported!");
}
llvm_unreachable("Invalid BuiltinType Kind!");
}
static bool TypeInfoIsInStandardLibrary(const PointerType *PointerTy) {
QualType PointeeTy = PointerTy->getPointeeType();
const BuiltinType *BuiltinTy = dyn_cast<BuiltinType>(PointeeTy);
if (!BuiltinTy)
return false;
Qualifiers Quals = PointeeTy.getQualifiers();
Quals.removeConst();
if (!Quals.empty())
return false;
return TypeInfoIsInStandardLibrary(BuiltinTy);
}
static bool IsStandardLibraryRTTIDescriptor(QualType Ty) {
if (const BuiltinType *BuiltinTy = dyn_cast<BuiltinType>(Ty))
return TypeInfoIsInStandardLibrary(BuiltinTy);
if (const PointerType *PointerTy = dyn_cast<PointerType>(Ty))
return TypeInfoIsInStandardLibrary(PointerTy);
return false;
}
static bool ShouldUseExternalRTTIDescriptor(CodeGenModule &CGM,
QualType Ty) {
ASTContext &Context = CGM.getContext();
if (!Context.getLangOpts().RTTI) return false;
if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
const CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
if (!RD->hasDefinition())
return false;
if (!RD->isDynamicClass())
return false;
bool IsDLLImport = RD->hasAttr<DLLImportAttr>();
if (CGM.getVTables().isVTableExternal(RD))
return IsDLLImport ? false : true;
if (IsDLLImport)
return true;
}
return false;
}
static bool IsIncompleteClassType(const RecordType *RecordTy) {
return !RecordTy->getDecl()->isCompleteDefinition();
}
static bool ContainsIncompleteClassType(QualType Ty) {
if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
if (IsIncompleteClassType(RecordTy))
return true;
}
if (const PointerType *PointerTy = dyn_cast<PointerType>(Ty))
return ContainsIncompleteClassType(PointerTy->getPointeeType());
if (const MemberPointerType *MemberPointerTy =
dyn_cast<MemberPointerType>(Ty)) {
const RecordType *ClassType = cast<RecordType>(MemberPointerTy->getClass());
if (IsIncompleteClassType(ClassType))
return true;
return ContainsIncompleteClassType(MemberPointerTy->getPointeeType());
}
return false;
}
static bool CanUseSingleInheritance(const CXXRecordDecl *RD) {
if (RD->getNumBases() != 1)
return false;
CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin();
if (Base->isVirtual())
return false;
if (Base->getAccessSpecifier() != AS_public)
return false;
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
if (!BaseDecl->isEmpty() &&
BaseDecl->isDynamicClass() != RD->isDynamicClass())
return false;
return true;
}
void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty) {
static const char * const ClassTypeInfo =
"_ZTVN10__cxxabiv117__class_type_infoE";
static const char * const SIClassTypeInfo =
"_ZTVN10__cxxabiv120__si_class_type_infoE";
static const char * const VMIClassTypeInfo =
"_ZTVN10__cxxabiv121__vmi_class_type_infoE";
const char *VTableName = nullptr;
switch (Ty->getTypeClass()) {
#define TYPE(Class, Base)
#define ABSTRACT_TYPE(Class, Base)
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
#include "clang/AST/TypeNodes.def"
llvm_unreachable("Non-canonical and dependent types shouldn't get here");
case Type::LValueReference:
case Type::RValueReference:
llvm_unreachable("References shouldn't get here");
case Type::Auto:
llvm_unreachable("Undeduced auto type shouldn't get here");
case Type::Pipe:
llvm_unreachable("Pipe types shouldn't get here");
case Type::Builtin:
case Type::Vector:
case Type::ExtVector:
case Type::Complex:
case Type::Atomic:
case Type::BlockPointer:
VTableName = "_ZTVN10__cxxabiv123__fundamental_type_infoE";
break;
case Type::ConstantArray:
case Type::IncompleteArray:
case Type::VariableArray:
VTableName = "_ZTVN10__cxxabiv117__array_type_infoE";
break;
case Type::FunctionNoProto:
case Type::FunctionProto:
VTableName = "_ZTVN10__cxxabiv120__function_type_infoE";
break;
case Type::Enum:
VTableName = "_ZTVN10__cxxabiv116__enum_type_infoE";
break;
case Type::Record: {
const CXXRecordDecl *RD =
cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
if (!RD->hasDefinition() || !RD->getNumBases()) {
VTableName = ClassTypeInfo;
} else if (CanUseSingleInheritance(RD)) {
VTableName = SIClassTypeInfo;
} else {
VTableName = VMIClassTypeInfo;
}
break;
}
case Type::ObjCObject:
Ty = cast<ObjCObjectType>(Ty)->getBaseType().getTypePtr();
if (isa<BuiltinType>(Ty)) {
VTableName = ClassTypeInfo;
break;
}
assert(isa<ObjCInterfaceType>(Ty));
case Type::ObjCInterface:
if (cast<ObjCInterfaceType>(Ty)->getDecl()->getSuperClass()) {
VTableName = SIClassTypeInfo;
} else {
VTableName = ClassTypeInfo;
}
break;
case Type::ObjCObjectPointer:
case Type::Pointer:
VTableName = "_ZTVN10__cxxabiv119__pointer_type_infoE";
break;
case Type::MemberPointer:
VTableName = "_ZTVN10__cxxabiv129__pointer_to_member_type_infoE";
break;
}
llvm::Constant *VTable =
CGM.getModule().getOrInsertGlobal(VTableName, CGM.Int8PtrTy);
llvm::Type *PtrDiffTy =
CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
llvm::Constant *Two = llvm::ConstantInt::get(PtrDiffTy, 2);
VTable =
llvm::ConstantExpr::getInBoundsGetElementPtr(CGM.Int8PtrTy, VTable, Two);
VTable = llvm::ConstantExpr::getBitCast(VTable, CGM.Int8PtrTy);
Fields.push_back(VTable);
}
static llvm::GlobalVariable::LinkageTypes getTypeInfoLinkage(CodeGenModule &CGM,
QualType Ty) {
if (ContainsIncompleteClassType(Ty))
return llvm::GlobalValue::InternalLinkage;
switch (Ty->getLinkage()) {
case NoLinkage:
case InternalLinkage:
case UniqueExternalLinkage:
return llvm::GlobalValue::InternalLinkage;
case VisibleNoLinkage:
case ExternalLinkage:
if (!CGM.getLangOpts().RTTI) {
return llvm::GlobalValue::LinkOnceODRLinkage;
}
if (const RecordType *Record = dyn_cast<RecordType>(Ty)) {
const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
if (RD->hasAttr<WeakAttr>())
return llvm::GlobalValue::WeakODRLinkage;
if (RD->isDynamicClass()) {
llvm::GlobalValue::LinkageTypes LT = CGM.getVTableLinkage(RD);
if (RD->hasAttr<DLLImportAttr>() &&
llvm::GlobalValue::isAvailableExternallyLinkage(LT))
LT = llvm::GlobalValue::LinkOnceODRLinkage;
return LT;
}
}
return llvm::GlobalValue::LinkOnceODRLinkage;
}
llvm_unreachable("Invalid linkage!");
}
llvm::Constant *ItaniumRTTIBuilder::BuildTypeInfo(QualType Ty, bool Force) {
Ty = CGM.getContext().getCanonicalType(Ty);
SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
llvm::GlobalVariable *OldGV = CGM.getModule().getNamedGlobal(Name);
if (OldGV && !OldGV->isDeclaration()) {
assert(!OldGV->hasAvailableExternallyLinkage() &&
"available_externally typeinfos not yet implemented");
return llvm::ConstantExpr::getBitCast(OldGV, CGM.Int8PtrTy);
}
bool IsStdLib = IsStandardLibraryRTTIDescriptor(Ty);
if (!Force && (IsStdLib || ShouldUseExternalRTTIDescriptor(CGM, Ty)))
return GetAddrOfExternalRTTIDescriptor(Ty);
llvm::GlobalVariable::LinkageTypes Linkage;
if (IsStdLib)
Linkage = llvm::GlobalValue::ExternalLinkage;
else
Linkage = getTypeInfoLinkage(CGM, Ty);
BuildVTablePointer(cast<Type>(Ty));
llvm::GlobalVariable *TypeName = GetAddrOfTypeName(Ty, Linkage);
llvm::Constant *TypeNameField;
ItaniumCXXABI::RTTIUniquenessKind RTTIUniqueness =
CXXABI.classifyRTTIUniqueness(Ty, Linkage);
if (RTTIUniqueness != ItaniumCXXABI::RUK_Unique) {
TypeNameField = llvm::ConstantExpr::getPtrToInt(TypeName, CGM.Int64Ty);
llvm::Constant *flag =
llvm::ConstantInt::get(CGM.Int64Ty, ((uint64_t)1) << 63);
TypeNameField = llvm::ConstantExpr::getAdd(TypeNameField, flag);
TypeNameField =
llvm::ConstantExpr::getIntToPtr(TypeNameField, CGM.Int8PtrTy);
} else {
TypeNameField = llvm::ConstantExpr::getBitCast(TypeName, CGM.Int8PtrTy);
}
Fields.push_back(TypeNameField);
switch (Ty->getTypeClass()) {
#define TYPE(Class, Base)
#define ABSTRACT_TYPE(Class, Base)
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
#include "clang/AST/TypeNodes.def"
llvm_unreachable("Non-canonical and dependent types shouldn't get here");
case Type::Builtin:
case Type::Vector:
case Type::ExtVector:
case Type::Complex:
case Type::BlockPointer:
break;
case Type::LValueReference:
case Type::RValueReference:
llvm_unreachable("References shouldn't get here");
case Type::Auto:
llvm_unreachable("Undeduced auto type shouldn't get here");
case Type::Pipe:
llvm_unreachable("Pipe type shouldn't get here");
case Type::ConstantArray:
case Type::IncompleteArray:
case Type::VariableArray:
break;
case Type::FunctionNoProto:
case Type::FunctionProto:
break;
case Type::Enum:
break;
case Type::Record: {
const CXXRecordDecl *RD =
cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
if (!RD->hasDefinition() || !RD->getNumBases()) {
break;
}
if (CanUseSingleInheritance(RD))
BuildSIClassTypeInfo(RD);
else
BuildVMIClassTypeInfo(RD);
break;
}
case Type::ObjCObject:
case Type::ObjCInterface:
BuildObjCObjectTypeInfo(cast<ObjCObjectType>(Ty));
break;
case Type::ObjCObjectPointer:
BuildPointerTypeInfo(cast<ObjCObjectPointerType>(Ty)->getPointeeType());
break;
case Type::Pointer:
BuildPointerTypeInfo(cast<PointerType>(Ty)->getPointeeType());
break;
case Type::MemberPointer:
BuildPointerToMemberTypeInfo(cast<MemberPointerType>(Ty));
break;
case Type::Atomic:
break;
}
llvm::Constant *Init = llvm::ConstantStruct::getAnon(Fields);
llvm::Module &M = CGM.getModule();
llvm::GlobalVariable *GV =
new llvm::GlobalVariable(M, Init->getType(),
true, Linkage, Init, Name);
if (OldGV) {
GV->takeName(OldGV);
llvm::Constant *NewPtr =
llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
OldGV->replaceAllUsesWith(NewPtr);
OldGV->eraseFromParent();
}
if (CGM.supportsCOMDAT() && GV->isWeakForLinker())
GV->setComdat(M.getOrInsertComdat(GV->getName()));
llvm::GlobalValue::VisibilityTypes llvmVisibility;
if (llvm::GlobalValue::isLocalLinkage(Linkage))
llvmVisibility = llvm::GlobalValue::DefaultVisibility;
else if (RTTIUniqueness == ItaniumCXXABI::RUK_NonUniqueHidden)
llvmVisibility = llvm::GlobalValue::HiddenVisibility;
else
llvmVisibility = CodeGenModule::GetLLVMVisibility(Ty->getVisibility());
TypeName->setVisibility(llvmVisibility);
GV->setVisibility(llvmVisibility);
return llvm::ConstantExpr::getBitCast(GV, CGM.Int8PtrTy);
}
static unsigned ComputeQualifierFlags(Qualifiers Quals) {
unsigned Flags = 0;
if (Quals.hasConst())
Flags |= ItaniumRTTIBuilder::PTI_Const;
if (Quals.hasVolatile())
Flags |= ItaniumRTTIBuilder::PTI_Volatile;
if (Quals.hasRestrict())
Flags |= ItaniumRTTIBuilder::PTI_Restrict;
return Flags;
}
void ItaniumRTTIBuilder::BuildObjCObjectTypeInfo(const ObjCObjectType *OT) {
const Type *T = OT->getBaseType().getTypePtr();
assert(isa<BuiltinType>(T) || isa<ObjCInterfaceType>(T));
if (isa<BuiltinType>(T)) return;
ObjCInterfaceDecl *Class = cast<ObjCInterfaceType>(T)->getDecl();
ObjCInterfaceDecl *Super = Class->getSuperClass();
if (!Super) return;
QualType SuperTy = CGM.getContext().getObjCInterfaceType(Super);
llvm::Constant *BaseTypeInfo =
ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(SuperTy);
Fields.push_back(BaseTypeInfo);
}
void ItaniumRTTIBuilder::BuildSIClassTypeInfo(const CXXRecordDecl *RD) {
llvm::Constant *BaseTypeInfo =
ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(RD->bases_begin()->getType());
Fields.push_back(BaseTypeInfo);
}
namespace {
struct SeenBases {
llvm::SmallPtrSet<const CXXRecordDecl *, 16> NonVirtualBases;
llvm::SmallPtrSet<const CXXRecordDecl *, 16> VirtualBases;
};
}
static unsigned ComputeVMIClassTypeInfoFlags(const CXXBaseSpecifier *Base,
SeenBases &Bases) {
unsigned Flags = 0;
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
if (Base->isVirtual()) {
if (!Bases.VirtualBases.insert(BaseDecl).second) {
Flags |= ItaniumRTTIBuilder::VMI_DiamondShaped;
} else {
if (Bases.NonVirtualBases.count(BaseDecl))
Flags |= ItaniumRTTIBuilder::VMI_NonDiamondRepeat;
}
} else {
if (!Bases.NonVirtualBases.insert(BaseDecl).second) {
Flags |= ItaniumRTTIBuilder::VMI_NonDiamondRepeat;
} else {
if (Bases.VirtualBases.count(BaseDecl))
Flags |= ItaniumRTTIBuilder::VMI_NonDiamondRepeat;
}
}
for (const auto &I : BaseDecl->bases())
Flags |= ComputeVMIClassTypeInfoFlags(&I, Bases);
return Flags;
}
static unsigned ComputeVMIClassTypeInfoFlags(const CXXRecordDecl *RD) {
unsigned Flags = 0;
SeenBases Bases;
for (const auto &I : RD->bases())
Flags |= ComputeVMIClassTypeInfoFlags(&I, Bases);
return Flags;
}
void ItaniumRTTIBuilder::BuildVMIClassTypeInfo(const CXXRecordDecl *RD) {
llvm::Type *UnsignedIntLTy =
CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
unsigned Flags = ComputeVMIClassTypeInfoFlags(RD);
Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, RD->getNumBases()));
if (!RD->getNumBases())
return;
llvm::Type *LongLTy =
CGM.getTypes().ConvertType(CGM.getContext().LongTy);
for (const auto &Base : RD->bases()) {
Fields.push_back(ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(Base.getType()));
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
int64_t OffsetFlags = 0;
CharUnits Offset;
if (Base.isVirtual())
Offset =
CGM.getItaniumVTableContext().getVirtualBaseOffsetOffset(RD, BaseDecl);
else {
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
Offset = Layout.getBaseClassOffset(BaseDecl);
};
OffsetFlags = uint64_t(Offset.getQuantity()) << 8;
if (Base.isVirtual())
OffsetFlags |= BCTI_Virtual;
if (Base.getAccessSpecifier() == AS_public)
OffsetFlags |= BCTI_Public;
Fields.push_back(llvm::ConstantInt::get(LongLTy, OffsetFlags));
}
}
void ItaniumRTTIBuilder::BuildPointerTypeInfo(QualType PointeeTy) {
Qualifiers Quals;
QualType UnqualifiedPointeeTy =
CGM.getContext().getUnqualifiedArrayType(PointeeTy, Quals);
unsigned Flags = ComputeQualifierFlags(Quals);
if (ContainsIncompleteClassType(UnqualifiedPointeeTy))
Flags |= PTI_Incomplete;
llvm::Type *UnsignedIntLTy =
CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
llvm::Constant *PointeeTypeInfo =
ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(UnqualifiedPointeeTy);
Fields.push_back(PointeeTypeInfo);
}
void
ItaniumRTTIBuilder::BuildPointerToMemberTypeInfo(const MemberPointerType *Ty) {
QualType PointeeTy = Ty->getPointeeType();
Qualifiers Quals;
QualType UnqualifiedPointeeTy =
CGM.getContext().getUnqualifiedArrayType(PointeeTy, Quals);
unsigned Flags = ComputeQualifierFlags(Quals);
const RecordType *ClassType = cast<RecordType>(Ty->getClass());
if (ContainsIncompleteClassType(UnqualifiedPointeeTy))
Flags |= PTI_Incomplete;
if (IsIncompleteClassType(ClassType))
Flags |= PTI_ContainingClassIncomplete;
llvm::Type *UnsignedIntLTy =
CGM.getTypes().ConvertType(CGM.getContext().UnsignedIntTy);
Fields.push_back(llvm::ConstantInt::get(UnsignedIntLTy, Flags));
llvm::Constant *PointeeTypeInfo =
ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(UnqualifiedPointeeTy);
Fields.push_back(PointeeTypeInfo);
Fields.push_back(
ItaniumRTTIBuilder(CXXABI).BuildTypeInfo(QualType(ClassType, 0)));
}
llvm::Constant *ItaniumCXXABI::getAddrOfRTTIDescriptor(QualType Ty) {
return ItaniumRTTIBuilder(*this).BuildTypeInfo(Ty);
}
void ItaniumCXXABI::EmitFundamentalRTTIDescriptor(QualType Type) {
QualType PointerType = getContext().getPointerType(Type);
QualType PointerTypeConst = getContext().getPointerType(Type.withConst());
ItaniumRTTIBuilder(*this).BuildTypeInfo(Type, true);
ItaniumRTTIBuilder(*this).BuildTypeInfo(PointerType, true);
ItaniumRTTIBuilder(*this).BuildTypeInfo(PointerTypeConst, true);
}
void ItaniumCXXABI::EmitFundamentalRTTIDescriptors() {
QualType FundamentalTypes[] = {
getContext().VoidTy, getContext().NullPtrTy,
getContext().BoolTy, getContext().WCharTy,
getContext().CharTy, getContext().UnsignedCharTy,
getContext().SignedCharTy, getContext().ShortTy,
getContext().UnsignedShortTy, getContext().IntTy,
getContext().UnsignedIntTy, getContext().LongTy,
getContext().UnsignedLongTy, getContext().LongLongTy,
getContext().UnsignedLongLongTy, getContext().HalfTy,
getContext().FloatTy, getContext().DoubleTy,
getContext().LongDoubleTy, getContext().Char16Ty,
getContext().Char32Ty,
};
for (const QualType &FundamentalType : FundamentalTypes)
EmitFundamentalRTTIDescriptor(FundamentalType);
}
ItaniumCXXABI::RTTIUniquenessKind ItaniumCXXABI::classifyRTTIUniqueness(
QualType CanTy, llvm::GlobalValue::LinkageTypes Linkage) const {
if (shouldRTTIBeUnique())
return RUK_Unique;
if (Linkage != llvm::GlobalValue::LinkOnceODRLinkage &&
Linkage != llvm::GlobalValue::WeakODRLinkage)
return RUK_Unique;
if (CanTy->getVisibility() != DefaultVisibility)
return RUK_Unique;
if (Linkage == llvm::GlobalValue::LinkOnceODRLinkage)
return RUK_NonUniqueHidden;
assert(Linkage == llvm::GlobalValue::WeakODRLinkage);
return RUK_NonUniqueVisible;
}
namespace {
enum class StructorCodegen { Emit, RAUW, Alias, COMDAT };
}
static StructorCodegen getCodegenToUse(CodeGenModule &CGM,
const CXXMethodDecl *MD) {
if (!CGM.getCodeGenOpts().CXXCtorDtorAliases)
return StructorCodegen::Emit;
if (MD->getParent()->getNumVBases())
return StructorCodegen::Emit;
GlobalDecl AliasDecl;
if (const auto *DD = dyn_cast<CXXDestructorDecl>(MD)) {
AliasDecl = GlobalDecl(DD, Dtor_Complete);
} else {
const auto *CD = cast<CXXConstructorDecl>(MD);
AliasDecl = GlobalDecl(CD, Ctor_Complete);
}
llvm::GlobalValue::LinkageTypes Linkage = CGM.getFunctionLinkage(AliasDecl);
if (llvm::GlobalValue::isDiscardableIfUnused(Linkage))
return StructorCodegen::RAUW;
if (!llvm::GlobalAlias::isValidLinkage(Linkage))
return StructorCodegen::RAUW;
if (llvm::GlobalValue::isWeakForLinker(Linkage)) {
if (CGM.getTarget().getTriple().isOSBinFormatELF())
return StructorCodegen::COMDAT;
return StructorCodegen::Emit;
}
return StructorCodegen::Alias;
}
static void emitConstructorDestructorAlias(CodeGenModule &CGM,
GlobalDecl AliasDecl,
GlobalDecl TargetDecl) {
llvm::GlobalValue::LinkageTypes Linkage = CGM.getFunctionLinkage(AliasDecl);
StringRef MangledName = CGM.getMangledName(AliasDecl);
llvm::GlobalValue *Entry = CGM.GetGlobalValue(MangledName);
if (Entry && !Entry->isDeclaration())
return;
auto *Aliasee = cast<llvm::GlobalValue>(CGM.GetAddrOfGlobal(TargetDecl));
auto *Alias = llvm::GlobalAlias::create(Linkage, "", Aliasee);
if (Entry) {
assert(Entry->getType() == Aliasee->getType() &&
"declaration exists with different type");
Alias->takeName(Entry);
Entry->replaceAllUsesWith(Alias);
Entry->eraseFromParent();
} else {
Alias->setName(MangledName);
}
CGM.setAliasAttributes(cast<NamedDecl>(AliasDecl.getDecl()), Alias);
}
void ItaniumCXXABI::emitCXXStructor(const CXXMethodDecl *MD,
StructorType Type) {
auto *CD = dyn_cast<CXXConstructorDecl>(MD);
const CXXDestructorDecl *DD = CD ? nullptr : cast<CXXDestructorDecl>(MD);
StructorCodegen CGType = getCodegenToUse(CGM, MD);
if (Type == StructorType::Complete) {
GlobalDecl CompleteDecl;
GlobalDecl BaseDecl;
if (CD) {
CompleteDecl = GlobalDecl(CD, Ctor_Complete);
BaseDecl = GlobalDecl(CD, Ctor_Base);
} else {
CompleteDecl = GlobalDecl(DD, Dtor_Complete);
BaseDecl = GlobalDecl(DD, Dtor_Base);
}
if (CGType == StructorCodegen::Alias || CGType == StructorCodegen::COMDAT) {
emitConstructorDestructorAlias(CGM, CompleteDecl, BaseDecl);
return;
}
if (CGType == StructorCodegen::RAUW) {
StringRef MangledName = CGM.getMangledName(CompleteDecl);
auto *Aliasee = CGM.GetAddrOfGlobal(BaseDecl);
CGM.addReplacement(MangledName, Aliasee);
return;
}
}
if (DD && Type == StructorType::Base && CGType != StructorCodegen::COMDAT &&
!CGM.TryEmitBaseDestructorAsAlias(DD))
return;
llvm::Function *Fn = CGM.codegenCXXStructor(MD, Type);
if (CGType == StructorCodegen::COMDAT) {
SmallString<256> Buffer;
llvm::raw_svector_ostream Out(Buffer);
if (DD)
getMangleContext().mangleCXXDtorComdat(DD, Out);
else
getMangleContext().mangleCXXCtorComdat(CD, Out);
llvm::Comdat *C = CGM.getModule().getOrInsertComdat(Out.str());
Fn->setComdat(C);
} else {
CGM.maybeSetTrivialComdat(*MD, *Fn);
}
}
static llvm::Constant *getBeginCatchFn(CodeGenModule &CGM) {
llvm::FunctionType *FTy = llvm::FunctionType::get(
CGM.Int8PtrTy, CGM.Int8PtrTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_begin_catch");
}
static llvm::Constant *getEndCatchFn(CodeGenModule &CGM) {
llvm::FunctionType *FTy =
llvm::FunctionType::get(CGM.VoidTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_end_catch");
}
static llvm::Constant *getGetExceptionPtrFn(CodeGenModule &CGM) {
llvm::FunctionType *FTy = llvm::FunctionType::get(
CGM.Int8PtrTy, CGM.Int8PtrTy, false);
return CGM.CreateRuntimeFunction(FTy, "__cxa_get_exception_ptr");
}
namespace {
struct CallEndCatch final : EHScopeStack::Cleanup {
CallEndCatch(bool MightThrow) : MightThrow(MightThrow) {}
bool MightThrow;
void Emit(CodeGenFunction &CGF, Flags flags) override {
if (!MightThrow) {
CGF.EmitNounwindRuntimeCall(getEndCatchFn(CGF.CGM));
return;
}
CGF.EmitRuntimeCallOrInvoke(getEndCatchFn(CGF.CGM));
}
};
}
static llvm::Value *CallBeginCatch(CodeGenFunction &CGF,
llvm::Value *Exn,
bool EndMightThrow) {
llvm::CallInst *call =
CGF.EmitNounwindRuntimeCall(getBeginCatchFn(CGF.CGM), Exn);
CGF.EHStack.pushCleanup<CallEndCatch>(NormalAndEHCleanup, EndMightThrow);
return call;
}
static void InitCatchParam(CodeGenFunction &CGF,
const VarDecl &CatchParam,
Address ParamAddr,
SourceLocation Loc) {
llvm::Value *Exn = CGF.getExceptionFromSlot();
CanQualType CatchType =
CGF.CGM.getContext().getCanonicalType(CatchParam.getType());
llvm::Type *LLVMCatchTy = CGF.ConvertTypeForMem(CatchType);
if (isa<ReferenceType>(CatchType)) {
QualType CaughtType = cast<ReferenceType>(CatchType)->getPointeeType();
bool EndCatchMightThrow = CaughtType->isRecordType();
llvm::Value *AdjustedExn = CallBeginCatch(CGF, Exn, EndCatchMightThrow);
if (const PointerType *PT = dyn_cast<PointerType>(CaughtType)) {
QualType PointeeType = PT->getPointeeType();
if (!PointeeType->isRecordType()) {
unsigned HeaderSize =
CGF.CGM.getTargetCodeGenInfo().getSizeOfUnwindException();
AdjustedExn = CGF.Builder.CreateConstGEP1_32(Exn, HeaderSize);
} else {
llvm::Type *PtrTy =
cast<llvm::PointerType>(LLVMCatchTy)->getElementType();
Address ExnPtrTmp =
CGF.CreateTempAlloca(PtrTy, CGF.getPointerAlign(), "exn.byref.tmp");
llvm::Value *Casted = CGF.Builder.CreateBitCast(AdjustedExn, PtrTy);
CGF.Builder.CreateStore(Casted, ExnPtrTmp);
AdjustedExn = ExnPtrTmp.getPointer();
}
}
llvm::Value *ExnCast =
CGF.Builder.CreateBitCast(AdjustedExn, LLVMCatchTy, "exn.byref");
CGF.Builder.CreateStore(ExnCast, ParamAddr);
return;
}
TypeEvaluationKind TEK = CGF.getEvaluationKind(CatchType);
if (TEK != TEK_Aggregate) {
llvm::Value *AdjustedExn = CallBeginCatch(CGF, Exn, false);
if (CatchType->hasPointerRepresentation()) {
llvm::Value *CastExn =
CGF.Builder.CreateBitCast(AdjustedExn, LLVMCatchTy, "exn.casted");
switch (CatchType.getQualifiers().getObjCLifetime()) {
case Qualifiers::OCL_Strong:
CastExn = CGF.EmitARCRetainNonBlock(CastExn);
case Qualifiers::OCL_None:
case Qualifiers::OCL_ExplicitNone:
case Qualifiers::OCL_Autoreleasing:
CGF.Builder.CreateStore(CastExn, ParamAddr);
return;
case Qualifiers::OCL_Weak:
CGF.EmitARCInitWeak(ParamAddr, CastExn);
return;
}
llvm_unreachable("bad ownership qualifier!");
}
llvm::Type *PtrTy = LLVMCatchTy->getPointerTo(0); llvm::Value *Cast = CGF.Builder.CreateBitCast(AdjustedExn, PtrTy);
LValue srcLV = CGF.MakeNaturalAlignAddrLValue(Cast, CatchType);
LValue destLV = CGF.MakeAddrLValue(ParamAddr, CatchType);
switch (TEK) {
case TEK_Complex:
CGF.EmitStoreOfComplex(CGF.EmitLoadOfComplex(srcLV, Loc), destLV,
true);
return;
case TEK_Scalar: {
llvm::Value *ExnLoad = CGF.EmitLoadOfScalar(srcLV, Loc);
CGF.EmitStoreOfScalar(ExnLoad, destLV, true);
return;
}
case TEK_Aggregate:
llvm_unreachable("evaluation kind filtered out!");
}
llvm_unreachable("bad evaluation kind");
}
assert(isa<RecordType>(CatchType) && "unexpected catch type!");
auto catchRD = CatchType->getAsCXXRecordDecl();
CharUnits caughtExnAlignment = CGF.CGM.getClassPointerAlignment(catchRD);
llvm::Type *PtrTy = LLVMCatchTy->getPointerTo(0);
const Expr *copyExpr = CatchParam.getInit();
if (!copyExpr) {
llvm::Value *rawAdjustedExn = CallBeginCatch(CGF, Exn, true);
Address adjustedExn(CGF.Builder.CreateBitCast(rawAdjustedExn, PtrTy),
caughtExnAlignment);
CGF.EmitAggregateCopy(ParamAddr, adjustedExn, CatchType);
return;
}
llvm::CallInst *rawAdjustedExn =
CGF.EmitNounwindRuntimeCall(getGetExceptionPtrFn(CGF.CGM), Exn);
Address adjustedExn(CGF.Builder.CreateBitCast(rawAdjustedExn, PtrTy),
caughtExnAlignment);
CodeGenFunction::OpaqueValueMapping
opaque(CGF, OpaqueValueExpr::findInCopyConstruct(copyExpr),
CGF.MakeAddrLValue(adjustedExn, CatchParam.getType()));
CGF.EHStack.pushTerminate();
CGF.EmitAggExpr(copyExpr,
AggValueSlot::forAddr(ParamAddr, Qualifiers(),
AggValueSlot::IsNotDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased));
CGF.EHStack.popTerminate();
opaque.pop();
CallBeginCatch(CGF, Exn, true);
}
void ItaniumCXXABI::emitBeginCatch(CodeGenFunction &CGF,
const CXXCatchStmt *S) {
VarDecl *CatchParam = S->getExceptionDecl();
if (!CatchParam) {
llvm::Value *Exn = CGF.getExceptionFromSlot();
CallBeginCatch(CGF, Exn, true);
return;
}
CodeGenFunction::AutoVarEmission var = CGF.EmitAutoVarAlloca(*CatchParam);
InitCatchParam(CGF, *CatchParam, var.getObjectAddress(CGF), S->getLocStart());
CGF.EmitAutoVarCleanups(var);
}
static llvm::Constant *getClangCallTerminateFn(CodeGenModule &CGM) {
llvm::FunctionType *fnTy =
llvm::FunctionType::get(CGM.VoidTy, CGM.Int8PtrTy, false);
llvm::Constant *fnRef =
CGM.CreateRuntimeFunction(fnTy, "__clang_call_terminate");
llvm::Function *fn = dyn_cast<llvm::Function>(fnRef);
if (fn && fn->empty()) {
fn->setDoesNotThrow();
fn->setDoesNotReturn();
fn->addFnAttr(llvm::Attribute::NoInline);
fn->setLinkage(llvm::Function::LinkOnceODRLinkage);
fn->setVisibility(llvm::Function::HiddenVisibility);
if (CGM.supportsCOMDAT())
fn->setComdat(CGM.getModule().getOrInsertComdat(fn->getName()));
llvm::BasicBlock *entry =
llvm::BasicBlock::Create(CGM.getLLVMContext(), "", fn);
CGBuilderTy builder(CGM, entry);
llvm::Value *exn = &*fn->arg_begin();
llvm::CallInst *catchCall = builder.CreateCall(getBeginCatchFn(CGM), exn);
catchCall->setDoesNotThrow();
catchCall->setCallingConv(CGM.getRuntimeCC());
llvm::CallInst *termCall = builder.CreateCall(CGM.getTerminateFn());
termCall->setDoesNotThrow();
termCall->setDoesNotReturn();
termCall->setCallingConv(CGM.getRuntimeCC());
builder.CreateUnreachable();
}
return fnRef;
}
llvm::CallInst *
ItaniumCXXABI::emitTerminateForUnexpectedException(CodeGenFunction &CGF,
llvm::Value *Exn) {
if (Exn) {
assert(CGF.CGM.getLangOpts().CPlusPlus);
return CGF.EmitNounwindRuntimeCall(getClangCallTerminateFn(CGF.CGM), Exn);
}
return CGF.EmitNounwindRuntimeCall(CGF.CGM.getTerminateFn());
}