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gerrit-public.fairphone.software / fp2-dev / platform / external / clang / 45147d0098a34c3705f74ca121b27d7736ac113a / . / lib / CodeGen / CGVtable.cpp
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//===--- CGVtable.cpp - Emit LLVM Code for C++ vtables --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code dealing with C++ code generation of virtual tables.
//
//===----------------------------------------------------------------------===//
#include "CodeGenModule.h"
#include "CodeGenFunction.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/RecordLayout.h"
#include "llvm/ADT/DenseSet.h"
#include <cstdio>
using namespace clang;
using namespace CodeGen;
namespace {
class VtableBuilder {
public:
/// Index_t - Vtable index type.
typedef uint64_t Index_t;
typedef std::vector<std::pair<GlobalDecl,
std::pair<GlobalDecl, ThunkAdjustment> > >
SavedAdjustmentsVectorTy;
private:
// VtableComponents - The components of the vtable being built.
typedef llvm::SmallVector<llvm::Constant *, 64> VtableComponentsVectorTy;
VtableComponentsVectorTy VtableComponents;
const bool BuildVtable;
llvm::Type *Ptr8Ty;
/// MostDerivedClass - The most derived class that this vtable is being
/// built for.
const CXXRecordDecl *MostDerivedClass;
/// LayoutClass - The most derived class used for virtual base layout
/// information.
const CXXRecordDecl *LayoutClass;
/// LayoutOffset - The offset for Class in LayoutClass.
uint64_t LayoutOffset;
/// BLayout - Layout for the most derived class that this vtable is being
/// built for.
const ASTRecordLayout &BLayout;
llvm::SmallSet<const CXXRecordDecl *, 32> IndirectPrimary;
llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
llvm::Constant *rtti;
llvm::LLVMContext &VMContext;
CodeGenModule &CGM; // Per-module state.
llvm::DenseMap<const CXXMethodDecl *, Index_t> VCall;
llvm::DenseMap<GlobalDecl, Index_t> VCallOffset;
llvm::DenseMap<GlobalDecl, Index_t> VCallOffsetForVCall;
// This is the offset to the nearest virtual base
llvm::DenseMap<const CXXMethodDecl *, Index_t> NonVirtualOffset;
llvm::DenseMap<const CXXRecordDecl *, Index_t> VBIndex;
/// PureVirtualFunction - Points to __cxa_pure_virtual.
llvm::Constant *PureVirtualFn;
/// VtableMethods - A data structure for keeping track of methods in a vtable.
/// Can add methods, override methods and iterate in vtable order.
class VtableMethods {
// MethodToIndexMap - Maps from a global decl to the index it has in the
// Methods vector.
llvm::DenseMap<GlobalDecl, uint64_t> MethodToIndexMap;
/// Methods - The methods, in vtable order.
typedef llvm::SmallVector<GlobalDecl, 16> MethodsVectorTy;
MethodsVectorTy Methods;
MethodsVectorTy OrigMethods;
public:
/// AddMethod - Add a method to the vtable methods.
void AddMethod(GlobalDecl GD) {
assert(!MethodToIndexMap.count(GD) &&
"Method has already been added!");
MethodToIndexMap[GD] = Methods.size();
Methods.push_back(GD);
OrigMethods.push_back(GD);
}
/// OverrideMethod - Replace a method with another.
void OverrideMethod(GlobalDecl OverriddenGD, GlobalDecl GD) {
llvm::DenseMap<GlobalDecl, uint64_t>::iterator i
= MethodToIndexMap.find(OverriddenGD);
assert(i != MethodToIndexMap.end() && "Did not find entry!");
// Get the index of the old decl.
uint64_t Index = i->second;
// Replace the old decl with the new decl.
Methods[Index] = GD;
// And add the new.
MethodToIndexMap[GD] = Index;
}
/// getIndex - Gives the index of a passed in GlobalDecl. Returns false if
/// the index couldn't be found.
bool getIndex(GlobalDecl GD, uint64_t &Index) const {
llvm::DenseMap<GlobalDecl, uint64_t>::const_iterator i
= MethodToIndexMap.find(GD);
if (i == MethodToIndexMap.end())
return false;
Index = i->second;
return true;
}
GlobalDecl getOrigMethod(uint64_t Index) const {
return OrigMethods[Index];
}
MethodsVectorTy::size_type size() const {
return Methods.size();
}
void clear() {
MethodToIndexMap.clear();
Methods.clear();
OrigMethods.clear();
}
GlobalDecl operator[](uint64_t Index) const {
return Methods[Index];
}
};
/// Methods - The vtable methods we're currently building.
VtableMethods Methods;
/// ThisAdjustments - For a given index in the vtable, contains the 'this'
/// pointer adjustment needed for a method.
typedef llvm::DenseMap<uint64_t, ThunkAdjustment> ThisAdjustmentsMapTy;
ThisAdjustmentsMapTy ThisAdjustments;
SavedAdjustmentsVectorTy SavedAdjustments;
/// BaseReturnTypes - Contains the base return types of methods who have been
/// overridden with methods whose return types require adjustment. Used for
/// generating covariant thunk information.
typedef llvm::DenseMap<uint64_t, CanQualType> BaseReturnTypesMapTy;
BaseReturnTypesMapTy BaseReturnTypes;
std::vector<Index_t> VCalls;
typedef std::pair<const CXXRecordDecl *, uint64_t> CtorVtable_t;
// subAddressPoints - Used to hold the AddressPoints (offsets) into the built
// vtable for use in computing the initializers for the VTT.
llvm::DenseMap<CtorVtable_t, int64_t> &subAddressPoints;
/// AddressPoints - Address points for this vtable.
CGVtableInfo::AddressPointsMapTy& AddressPoints;
typedef CXXRecordDecl::method_iterator method_iter;
const uint32_t LLVMPointerWidth;
Index_t extra;
typedef std::vector<std::pair<const CXXRecordDecl *, int64_t> > Path_t;
static llvm::DenseMap<CtorVtable_t, int64_t>&
AllocAddressPoint(CodeGenModule &cgm, const CXXRecordDecl *l,
const CXXRecordDecl *c) {
CGVtableInfo::AddrMap_t *&oref = cgm.getVtableInfo().AddressPoints[l];
if (oref == 0)
oref = new CGVtableInfo::AddrMap_t;
llvm::DenseMap<CtorVtable_t, int64_t> *&ref = (*oref)[c];
if (ref == 0)
ref = new llvm::DenseMap<CtorVtable_t, int64_t>;
return *ref;
}
#if 0
bool TemplateParameterListsAreEqual(TemplateParameterList *New,
TemplateParameterList *Old,
TemplateParameterListEqualKind Kind) {
assert(0 && "template in vtable");
if (Old->size() != New->size()) {
return false;
}
for (TemplateParameterList::iterator OldParm = Old->begin(),
OldParmEnd = Old->end(), NewParm = New->begin();
OldParm != OldParmEnd; ++OldParm, ++NewParm) {
if ((*OldParm)->getKind() != (*NewParm)->getKind()) {
return false;
}
if (isa<TemplateTypeParmDecl>(*OldParm)) {
// Okay; all template type parameters are equivalent (since we
// know we're at the same index).
} else if (NonTypeTemplateParmDecl *OldNTTP
= dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) {
// The types of non-type template parameters must agree.
NonTypeTemplateParmDecl *NewNTTP
= cast<NonTypeTemplateParmDecl>(*NewParm);
// If we are matching a template template argument to a template
// template parameter and one of the non-type template parameter types
// is dependent, then we must wait until template instantiation time
// to actually compare the arguments.
if (Kind == TPL_TemplateTemplateArgumentMatch &&
(OldNTTP->getType()->isDependentType() ||
NewNTTP->getType()->isDependentType()))
continue;
if (Context.getCanonicalType(OldNTTP->getType()) !=
Context.getCanonicalType(NewNTTP->getType())) {
return false;
}
} else {
// The template parameter lists of template template
// parameters must agree.
assert(isa<TemplateTemplateParmDecl>(*OldParm) &&
"Only template template parameters handled here");
TemplateTemplateParmDecl *OldTTP
= cast<TemplateTemplateParmDecl>(*OldParm);
TemplateTemplateParmDecl *NewTTP
= cast<TemplateTemplateParmDecl>(*NewParm);
if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(),
OldTTP->getTemplateParameters(),
(Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind)))
return false;
}
}
return true;
}
#endif
bool DclIsSame(const FunctionDecl *New, const FunctionDecl *Old) {
FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate();
FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate();
// C++ [temp.fct]p2:
// A function template can be overloaded with other function templates
// and with normal (non-template) functions.
if ((OldTemplate == 0) != (NewTemplate == 0))
return false;
// Is the function New an overload of the function Old?
QualType OldQType = CGM.getContext().getCanonicalType(Old->getType());
QualType NewQType = CGM.getContext().getCanonicalType(New->getType());
// Compare the signatures (C++ 1.3.10) of the two functions to
// determine whether they are overloads. If we find any mismatch
// in the signature, they are overloads.
// If either of these functions is a K&R-style function (no
// prototype), then we consider them to have matching signatures.
if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) ||
isa<FunctionNoProtoType>(NewQType.getTypePtr()))
return true;
FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType);
FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType);
// The signature of a function includes the types of its
// parameters (C++ 1.3.10), which includes the presence or absence
// of the ellipsis; see C++ DR 357).
if (OldQType != NewQType &&
(OldType->getNumArgs() != NewType->getNumArgs() ||
OldType->isVariadic() != NewType->isVariadic() ||
!std::equal(OldType->arg_type_begin(), OldType->arg_type_end(),
NewType->arg_type_begin())))
return false;
#if 0
// C++ [temp.over.link]p4:
// The signature of a function template consists of its function
// signature, its return type and its template parameter list. The names
// of the template parameters are significant only for establishing the
// relationship between the template parameters and the rest of the
// signature.
//
// We check the return type and template parameter lists for function
// templates first; the remaining checks follow.
if (NewTemplate &&
(!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
OldTemplate->getTemplateParameters(),
TPL_TemplateMatch) ||
OldType->getResultType() != NewType->getResultType()))
return false;
#endif
// If the function is a class member, its signature includes the
// cv-qualifiers (if any) on the function itself.
//
// As part of this, also check whether one of the member functions
// is static, in which case they are not overloads (C++
// 13.1p2). While not part of the definition of the signature,
// this check is important to determine whether these functions
// can be overloaded.
const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old);
const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New);
if (OldMethod && NewMethod &&
!OldMethod->isStatic() && !NewMethod->isStatic() &&
OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers())
return false;
// The signatures match; this is not an overload.
return true;
}
typedef llvm::DenseMap<const CXXMethodDecl *, const CXXMethodDecl*>
ForwardUnique_t;
ForwardUnique_t ForwardUnique;
llvm::DenseMap<const CXXMethodDecl*, const CXXMethodDecl*> UniqueOverrider;
void BuildUniqueOverrider(const CXXMethodDecl *U, const CXXMethodDecl *MD) {
const CXXMethodDecl *PrevU = UniqueOverrider[MD];
assert(U && "no unique overrider");
if (PrevU == U)
return;
if (PrevU != U && PrevU != 0) {
// If already set, note the two sets as the same
if (0)
printf("%s::%s same as %s::%s\n",
PrevU->getParent()->getNameAsCString(),
PrevU->getNameAsCString(),
U->getParent()->getNameAsCString(),
U->getNameAsCString());
ForwardUnique[PrevU] = U;
return;
}
// Not set, set it now
if (0)
printf("marking %s::%s %p override as %s::%s\n",
MD->getParent()->getNameAsCString(),
MD->getNameAsCString(),
(void*)MD,
U->getParent()->getNameAsCString(),
U->getNameAsCString());
UniqueOverrider[MD] = U;
for (CXXMethodDecl::method_iterator mi = MD->begin_overridden_methods(),
me = MD->end_overridden_methods(); mi != me; ++mi) {
BuildUniqueOverrider(U, *mi);
}
}
void BuildUniqueOverriders(const CXXRecordDecl *RD) {
if (0) printf("walking %s\n", RD->getNameAsCString());
for (CXXRecordDecl::method_iterator i = RD->method_begin(),
e = RD->method_end(); i != e; ++i) {
const CXXMethodDecl *MD = *i;
if (!MD->isVirtual())
continue;
if (UniqueOverrider[MD] == 0) {
// Only set this, if it hasn't been set yet.
BuildUniqueOverrider(MD, MD);
if (0)
printf("top set is %s::%s %p\n",
MD->getParent()->getNameAsCString(),
MD->getNameAsCString(),
(void*)MD);
ForwardUnique[MD] = MD;
}
}
for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
e = RD->bases_end(); i != e; ++i) {
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
BuildUniqueOverriders(Base);
}
}
static int DclCmp(const void *p1, const void *p2) {
const CXXMethodDecl *MD1 = (const CXXMethodDecl *)p1;
const CXXMethodDecl *MD2 = (const CXXMethodDecl *)p2;
return (MD1->getIdentifier() - MD2->getIdentifier());
}
void MergeForwarding() {
typedef llvm::SmallVector<const CXXMethodDecl *, 100> A_t;
A_t A;
for (ForwardUnique_t::iterator I = ForwardUnique.begin(),
E = ForwardUnique.end(); I != E; ++I) {
if (I->first == I->second)
// Only add the roots of all trees
A.push_back(I->first);
}
llvm::array_pod_sort(A.begin(), A.end(), DclCmp);
for (A_t::iterator I = A.begin(),
E = A.end(); I != E; ++I) {
A_t::iterator J = I;
while (++J != E && DclCmp(*I, *J) == 0)
if (DclIsSame(*I, *J)) {
printf("connecting %s\n", (*I)->getNameAsCString());
ForwardUnique[*J] = *I;
}
}
}
const CXXMethodDecl *getUnique(const CXXMethodDecl *MD) {
const CXXMethodDecl *U = UniqueOverrider[MD];
assert(U && "unique overrider not found");
while (ForwardUnique.count(U)) {
const CXXMethodDecl *NU = ForwardUnique[U];
if (NU == U) break;
U = NU;
}
return U;
}
GlobalDecl getUnique(GlobalDecl GD) {
const CXXMethodDecl *Unique = getUnique(cast<CXXMethodDecl>(GD.getDecl()));
if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Unique))
return GlobalDecl(CD, GD.getCtorType());
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(Unique))
return GlobalDecl(DD, GD.getDtorType());
return Unique;
}
/// getPureVirtualFn - Return the __cxa_pure_virtual function.
llvm::Constant* getPureVirtualFn() {
if (!PureVirtualFn) {
const llvm::FunctionType *Ty =
llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
/*isVarArg=*/false);
PureVirtualFn = wrap(CGM.CreateRuntimeFunction(Ty, "__cxa_pure_virtual"));
}
return PureVirtualFn;
}
public:
VtableBuilder(const CXXRecordDecl *MostDerivedClass,
const CXXRecordDecl *l, uint64_t lo, CodeGenModule &cgm,
bool build, CGVtableInfo::AddressPointsMapTy& AddressPoints)
: BuildVtable(build), MostDerivedClass(MostDerivedClass), LayoutClass(l),
LayoutOffset(lo), BLayout(cgm.getContext().getASTRecordLayout(l)),
rtti(0), VMContext(cgm.getModule().getContext()),CGM(cgm),
PureVirtualFn(0),
subAddressPoints(AllocAddressPoint(cgm, l, MostDerivedClass)),
AddressPoints(AddressPoints),
LLVMPointerWidth(cgm.getContext().Target.getPointerWidth(0))
{
Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
if (BuildVtable) {
QualType ClassType = CGM.getContext().getTagDeclType(MostDerivedClass);
rtti = CGM.GetAddrOfRTTIDescriptor(ClassType);
}
BuildUniqueOverriders(MostDerivedClass);
MergeForwarding();
}
// getVtableComponents - Returns a reference to the vtable components.
const VtableComponentsVectorTy &getVtableComponents() const {
return VtableComponents;
}
llvm::DenseMap<const CXXRecordDecl *, uint64_t> &getVBIndex()
{ return VBIndex; }
SavedAdjustmentsVectorTy &getSavedAdjustments()
{ return SavedAdjustments; }
llvm::Constant *wrap(Index_t i) {
llvm::Constant *m;
m = llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), i);
return llvm::ConstantExpr::getIntToPtr(m, Ptr8Ty);
}
llvm::Constant *wrap(llvm::Constant *m) {
return llvm::ConstantExpr::getBitCast(m, Ptr8Ty);
}
//#define D1(x)
#define D1(X) do { if (getenv("DEBUG")) { X; } } while (0)
void GenerateVBaseOffsets(const CXXRecordDecl *RD, uint64_t Offset,
bool updateVBIndex, Index_t current_vbindex) {
for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
e = RD->bases_end(); i != e; ++i) {
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
Index_t next_vbindex = current_vbindex;
if (i->isVirtual() && !SeenVBase.count(Base)) {
SeenVBase.insert(Base);
if (updateVBIndex) {
next_vbindex = (ssize_t)(-(VCalls.size()*LLVMPointerWidth/8)
- 3*LLVMPointerWidth/8);
VBIndex[Base] = next_vbindex;
}
int64_t BaseOffset = -(Offset/8) + BLayout.getVBaseClassOffset(Base)/8;
VCalls.push_back((0?700:0) + BaseOffset);
D1(printf(" vbase for %s at %d delta %d most derived %s\n",
Base->getNameAsCString(),
(int)-VCalls.size()-3, (int)BaseOffset,
MostDerivedClass->getNameAsCString()));
}
// We also record offsets for non-virtual bases to closest enclosing
// virtual base. We do this so that we don't have to search
// for the nearst virtual base class when generating thunks.
if (updateVBIndex && VBIndex.count(Base) == 0)
VBIndex[Base] = next_vbindex;
GenerateVBaseOffsets(Base, Offset, updateVBIndex, next_vbindex);
}
}
void StartNewTable() {
SeenVBase.clear();
}
Index_t getNVOffset_1(const CXXRecordDecl *D, const CXXRecordDecl *B,
Index_t Offset = 0) {
if (B == D)
return Offset;
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(D);
for (CXXRecordDecl::base_class_const_iterator i = D->bases_begin(),
e = D->bases_end(); i != e; ++i) {
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
int64_t BaseOffset = 0;
if (!i->isVirtual())
BaseOffset = Offset + Layout.getBaseClassOffset(Base);
int64_t o = getNVOffset_1(Base, B, BaseOffset);
if (o >= 0)
return o;
}
return -1;
}
/// getNVOffset - Returns the non-virtual offset for the given (B) base of the
/// derived class D.
Index_t getNVOffset(QualType qB, QualType qD) {
qD = qD->getPointeeType();
qB = qB->getPointeeType();
CXXRecordDecl *D = cast<CXXRecordDecl>(qD->getAs<RecordType>()->getDecl());
CXXRecordDecl *B = cast<CXXRecordDecl>(qB->getAs<RecordType>()->getDecl());
int64_t o = getNVOffset_1(D, B);
if (o >= 0)
return o;
assert(false && "FIXME: non-virtual base not found");
return 0;
}
/// getVbaseOffset - Returns the index into the vtable for the virtual base
/// offset for the given (B) virtual base of the derived class D.
Index_t getVbaseOffset(QualType qB, QualType qD) {
qD = qD->getPointeeType();
qB = qB->getPointeeType();
CXXRecordDecl *D = cast<CXXRecordDecl>(qD->getAs<RecordType>()->getDecl());
CXXRecordDecl *B = cast<CXXRecordDecl>(qB->getAs<RecordType>()->getDecl());
if (D != MostDerivedClass)
return CGM.getVtableInfo().getVirtualBaseOffsetIndex(D, B);
llvm::DenseMap<const CXXRecordDecl *, Index_t>::iterator i;
i = VBIndex.find(B);
if (i != VBIndex.end())
return i->second;
assert(false && "FIXME: Base not found");
return 0;
}
bool OverrideMethod(GlobalDecl GD, bool MorallyVirtual,
Index_t OverrideOffset, Index_t Offset,
int64_t CurrentVBaseOffset);
/// AppendMethods - Append the current methods to the vtable.
void AppendMethodsToVtable();
llvm::Constant *WrapAddrOf(GlobalDecl GD) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
const llvm::Type *Ty = CGM.getTypes().GetFunctionTypeForVtable(MD);
return wrap(CGM.GetAddrOfFunction(GD, Ty));
}
void OverrideMethods(Path_t *Path, bool MorallyVirtual, int64_t Offset,
int64_t CurrentVBaseOffset) {
for (Path_t::reverse_iterator i = Path->rbegin(),
e = Path->rend(); i != e; ++i) {
const CXXRecordDecl *RD = i->first;
int64_t OverrideOffset = i->second;
for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
++mi) {
const CXXMethodDecl *MD = *mi;
if (!MD->isVirtual())
continue;
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
// Override both the complete and the deleting destructor.
GlobalDecl CompDtor(DD, Dtor_Complete);
OverrideMethod(CompDtor, MorallyVirtual, OverrideOffset, Offset,
CurrentVBaseOffset);
GlobalDecl DeletingDtor(DD, Dtor_Deleting);
OverrideMethod(DeletingDtor, MorallyVirtual, OverrideOffset, Offset,
CurrentVBaseOffset);
} else {
OverrideMethod(MD, MorallyVirtual, OverrideOffset, Offset,
CurrentVBaseOffset);
}
}
}
}
void AddMethod(const GlobalDecl GD, bool MorallyVirtual, Index_t Offset,
int64_t CurrentVBaseOffset) {
// If we can find a previously allocated slot for this, reuse it.
if (OverrideMethod(GD, MorallyVirtual, Offset, Offset,
CurrentVBaseOffset))
return;
D1(printf(" vfn for %s at %d\n",
dyn_cast<CXXMethodDecl>(GD.getDecl())->getNameAsCString(),
(int)Methods.size()));
// We didn't find an entry in the vtable that we could use, add a new
// entry.
Methods.AddMethod(GD);
VCallOffset[GD] = Offset/8 - CurrentVBaseOffset/8;
if (MorallyVirtual) {
GlobalDecl UGD = getUnique(GD);
const CXXMethodDecl *UMD = cast<CXXMethodDecl>(UGD.getDecl());
assert(UMD && "final overrider not found");
Index_t &idx = VCall[UMD];
// Allocate the first one, after that, we reuse the previous one.
if (idx == 0) {
VCallOffsetForVCall[UGD] = Offset/8;
NonVirtualOffset[UMD] = Offset/8 - CurrentVBaseOffset/8;
idx = VCalls.size()+1;
VCalls.push_back(Offset/8 - CurrentVBaseOffset/8);
D1(printf(" vcall for %s at %d with delta %d\n",
dyn_cast<CXXMethodDecl>(GD.getDecl())->getNameAsCString(),
(int)-VCalls.size()-3, (int)VCalls[idx-1]));
}
}
}
void AddMethods(const CXXRecordDecl *RD, bool MorallyVirtual,
Index_t Offset, int64_t CurrentVBaseOffset) {
for (method_iter mi = RD->method_begin(), me = RD->method_end(); mi != me;
++mi) {
const CXXMethodDecl *MD = *mi;
if (!MD->isVirtual())
continue;
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
// For destructors, add both the complete and the deleting destructor
// to the vtable.
AddMethod(GlobalDecl(DD, Dtor_Complete), MorallyVirtual, Offset,
CurrentVBaseOffset);
AddMethod(GlobalDecl(DD, Dtor_Deleting), MorallyVirtual, Offset,
CurrentVBaseOffset);
} else
AddMethod(MD, MorallyVirtual, Offset, CurrentVBaseOffset);
}
}
void NonVirtualBases(const CXXRecordDecl *RD, const ASTRecordLayout &Layout,
const CXXRecordDecl *PrimaryBase,
bool PrimaryBaseWasVirtual, bool MorallyVirtual,
int64_t Offset, int64_t CurrentVBaseOffset,
Path_t *Path) {
Path->push_back(std::make_pair(RD, Offset));
for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
e = RD->bases_end(); i != e; ++i) {
if (i->isVirtual())
continue;
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
uint64_t o = Offset + Layout.getBaseClassOffset(Base);
StartNewTable();
GenerateVtableForBase(Base, o, MorallyVirtual, false,
true, Base == PrimaryBase && !PrimaryBaseWasVirtual,
CurrentVBaseOffset, Path);
}
Path->pop_back();
}
// #define D(X) do { X; } while (0)
#define D(X)
void insertVCalls(int InsertionPoint) {
D1(printf("============= combining vbase/vcall\n"));
D(VCalls.insert(VCalls.begin(), 673));
D(VCalls.push_back(672));
VtableComponents.insert(VtableComponents.begin() + InsertionPoint,
VCalls.size(), 0);
if (BuildVtable) {
// The vcalls come first...
for (std::vector<Index_t>::reverse_iterator i = VCalls.rbegin(),
e = VCalls.rend();
i != e; ++i)
VtableComponents[InsertionPoint++] = wrap((0?600:0) + *i);
}
VCalls.clear();
VCall.clear();
VCallOffsetForVCall.clear();
VCallOffset.clear();
NonVirtualOffset.clear();
}
void AddAddressPoints(const CXXRecordDecl *RD, uint64_t Offset,
Index_t AddressPoint) {
D1(printf("XXX address point for %s in %s layout %s at offset %d is %d\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString(),
LayoutClass->getNameAsCString(), (int)Offset, (int)AddressPoint));
subAddressPoints[std::make_pair(RD, Offset)] = AddressPoint;
AddressPoints[BaseSubobject(RD, Offset)] = AddressPoint;
// Now also add the address point for all our primary bases.
while (1) {
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
RD = Layout.getPrimaryBase();
const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
// FIXME: Double check this.
if (RD == 0)
break;
if (PrimaryBaseWasVirtual &&
BLayout.getVBaseClassOffset(RD) != Offset)
break;
D1(printf("XXX address point for %s in %s layout %s at offset %d is %d\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString(),
LayoutClass->getNameAsCString(), (int)Offset, (int)AddressPoint));
subAddressPoints[std::make_pair(RD, Offset)] = AddressPoint;
AddressPoints[BaseSubobject(RD, Offset)] = AddressPoint;
}
}
void FinishGenerateVtable(const CXXRecordDecl *RD,
const ASTRecordLayout &Layout,
const CXXRecordDecl *PrimaryBase,
bool ForNPNVBases, bool WasPrimaryBase,
bool PrimaryBaseWasVirtual,
bool MorallyVirtual, int64_t Offset,
bool ForVirtualBase, int64_t CurrentVBaseOffset,
Path_t *Path) {
bool alloc = false;
if (Path == 0) {
alloc = true;
Path = new Path_t;
}
StartNewTable();
extra = 0;
Index_t AddressPoint = 0;
int VCallInsertionPoint = 0;
if (!ForNPNVBases || !WasPrimaryBase) {
bool DeferVCalls = MorallyVirtual || ForVirtualBase;
VCallInsertionPoint = VtableComponents.size();
if (!DeferVCalls) {
insertVCalls(VCallInsertionPoint);
} else
// FIXME: just for extra, or for all uses of VCalls.size post this?
extra = -VCalls.size();
// Add the offset to top.
VtableComponents.push_back(BuildVtable ? wrap(-((Offset-LayoutOffset)/8)) : 0);
// Add the RTTI information.
VtableComponents.push_back(rtti);
AddressPoint = VtableComponents.size();
AppendMethodsToVtable();
}
// and then the non-virtual bases.
NonVirtualBases(RD, Layout, PrimaryBase, PrimaryBaseWasVirtual,
MorallyVirtual, Offset, CurrentVBaseOffset, Path);
if (ForVirtualBase) {
// FIXME: We're adding to VCalls in callers, we need to do the overrides
// in the inner part, so that we know the complete set of vcalls during
// the build and don't have to insert into methods. Saving out the
// AddressPoint here, would need to be fixed, if we didn't do that. Also
// retroactively adding vcalls for overrides later wind up in the wrong
// place, the vcall slot has to be alloted during the walk of the base
// when the function is first introduces.
AddressPoint += VCalls.size();
insertVCalls(VCallInsertionPoint);
}
if (!ForNPNVBases || !WasPrimaryBase)
AddAddressPoints(RD, Offset, AddressPoint);
if (alloc) {
delete Path;
}
}
void Primaries(const CXXRecordDecl *RD, bool MorallyVirtual, int64_t Offset,
bool updateVBIndex, Index_t current_vbindex,
int64_t CurrentVBaseOffset) {
if (!RD->isDynamicClass())
return;
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
// vtables are composed from the chain of primaries.
if (PrimaryBase && !PrimaryBaseWasVirtual) {
D1(printf(" doing primaries for %s most derived %s\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString()));
Primaries(PrimaryBase, PrimaryBaseWasVirtual|MorallyVirtual, Offset,
updateVBIndex, current_vbindex, CurrentVBaseOffset);
}
D1(printf(" doing vcall entries for %s most derived %s\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString()));
// And add the virtuals for the class to the primary vtable.
AddMethods(RD, MorallyVirtual, Offset, CurrentVBaseOffset);
}
void VBPrimaries(const CXXRecordDecl *RD, bool MorallyVirtual, int64_t Offset,
bool updateVBIndex, Index_t current_vbindex,
bool RDisVirtualBase, int64_t CurrentVBaseOffset,
bool bottom) {
if (!RD->isDynamicClass())
return;
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
// vtables are composed from the chain of primaries.
if (PrimaryBase) {
int BaseCurrentVBaseOffset = CurrentVBaseOffset;
if (PrimaryBaseWasVirtual) {
IndirectPrimary.insert(PrimaryBase);
BaseCurrentVBaseOffset = BLayout.getVBaseClassOffset(PrimaryBase);
}
D1(printf(" doing primaries for %s most derived %s\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString()));
VBPrimaries(PrimaryBase, PrimaryBaseWasVirtual|MorallyVirtual, Offset,
updateVBIndex, current_vbindex, PrimaryBaseWasVirtual,
BaseCurrentVBaseOffset, false);
}
D1(printf(" doing vbase entries for %s most derived %s\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString()));
GenerateVBaseOffsets(RD, Offset, updateVBIndex, current_vbindex);
if (RDisVirtualBase || bottom) {
Primaries(RD, MorallyVirtual, Offset, updateVBIndex, current_vbindex,
CurrentVBaseOffset);
}
}
void GenerateVtableForBase(const CXXRecordDecl *RD, int64_t Offset = 0,
bool MorallyVirtual = false,
bool ForVirtualBase = false,
bool ForNPNVBases = false,
bool WasPrimaryBase = true,
int CurrentVBaseOffset = 0,
Path_t *Path = 0) {
if (!RD->isDynamicClass())
return;
// Construction vtable don't need parts that have no virtual bases and
// aren't morally virtual.
if ((LayoutClass != MostDerivedClass) &&
RD->getNumVBases() == 0 && !MorallyVirtual)
return;
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
extra = 0;
D1(printf("building entries for base %s most derived %s\n",
RD->getNameAsCString(), MostDerivedClass->getNameAsCString()));
if (ForVirtualBase)
extra = VCalls.size();
if (!ForNPNVBases || !WasPrimaryBase) {
VBPrimaries(RD, MorallyVirtual, Offset, !ForVirtualBase, 0,
ForVirtualBase, CurrentVBaseOffset, true);
if (Path)
OverrideMethods(Path, MorallyVirtual, Offset, CurrentVBaseOffset);
}
FinishGenerateVtable(RD, Layout, PrimaryBase, ForNPNVBases, WasPrimaryBase,
PrimaryBaseWasVirtual, MorallyVirtual, Offset,
ForVirtualBase, CurrentVBaseOffset, Path);
}
void GenerateVtableForVBases(const CXXRecordDecl *RD,
int64_t Offset = 0,
Path_t *Path = 0) {
bool alloc = false;
if (Path == 0) {
alloc = true;
Path = new Path_t;
}
// FIXME: We also need to override using all paths to a virtual base,
// right now, we just process the first path
Path->push_back(std::make_pair(RD, Offset));
for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
e = RD->bases_end(); i != e; ++i) {
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
if (i->isVirtual() && !IndirectPrimary.count(Base)) {
// Mark it so we don't output it twice.
IndirectPrimary.insert(Base);
StartNewTable();
VCall.clear();
int64_t BaseOffset = BLayout.getVBaseClassOffset(Base);
int64_t CurrentVBaseOffset = BaseOffset;
D1(printf("vtable %s virtual base %s\n",
MostDerivedClass->getNameAsCString(), Base->getNameAsCString()));
GenerateVtableForBase(Base, BaseOffset, true, true, false,
true, CurrentVBaseOffset, Path);
}
int64_t BaseOffset;
if (i->isVirtual())
BaseOffset = BLayout.getVBaseClassOffset(Base);
else {
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
BaseOffset = Offset + Layout.getBaseClassOffset(Base);
}
if (Base->getNumVBases()) {
GenerateVtableForVBases(Base, BaseOffset, Path);
}
}
Path->pop_back();
if (alloc)
delete Path;
}
};
} // end anonymous namespace
/// TypeConversionRequiresAdjustment - Returns whether conversion from a
/// derived type to a base type requires adjustment.
static bool
TypeConversionRequiresAdjustment(ASTContext &Ctx,
const CXXRecordDecl *DerivedDecl,
const CXXRecordDecl *BaseDecl) {
CXXBasePaths Paths(/*FindAmbiguities=*/false,
/*RecordPaths=*/true, /*DetectVirtual=*/true);
if (!const_cast<CXXRecordDecl *>(DerivedDecl)->
isDerivedFrom(const_cast<CXXRecordDecl *>(BaseDecl), Paths)) {
assert(false && "Class must be derived from the passed in base class!");
return false;
}
// If we found a virtual base we always want to require adjustment.
if (Paths.getDetectedVirtual())
return true;
const CXXBasePath &Path = Paths.front();
for (size_t Start = 0, End = Path.size(); Start != End; ++Start) {
const CXXBasePathElement &Element = Path[Start];
// Check the base class offset.
const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Element.Class);
const RecordType *BaseType = Element.Base->getType()->getAs<RecordType>();
const CXXRecordDecl *Base = cast<CXXRecordDecl>(BaseType->getDecl());
if (Layout.getBaseClassOffset(Base) != 0) {
// This requires an adjustment.
return true;
}
}
return false;
}
static bool
TypeConversionRequiresAdjustment(ASTContext &Ctx,
QualType DerivedType, QualType BaseType) {
// Canonicalize the types.
QualType CanDerivedType = Ctx.getCanonicalType(DerivedType);
QualType CanBaseType = Ctx.getCanonicalType(BaseType);
assert(CanDerivedType->getTypeClass() == CanBaseType->getTypeClass() &&
"Types must have same type class!");
if (CanDerivedType == CanBaseType) {
// No adjustment needed.
return false;
}
if (const ReferenceType *RT = dyn_cast<ReferenceType>(CanDerivedType)) {
CanDerivedType = RT->getPointeeType();
CanBaseType = cast<ReferenceType>(CanBaseType)->getPointeeType();
} else if (const PointerType *PT = dyn_cast<PointerType>(CanDerivedType)) {
CanDerivedType = PT->getPointeeType();
CanBaseType = cast<PointerType>(CanBaseType)->getPointeeType();
} else {
assert(false && "Unexpected return type!");
}
if (CanDerivedType == CanBaseType) {
// No adjustment needed.
return false;
}
const CXXRecordDecl *DerivedDecl =
cast<CXXRecordDecl>(cast<RecordType>(CanDerivedType)->getDecl());
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(cast<RecordType>(CanBaseType)->getDecl());
return TypeConversionRequiresAdjustment(Ctx, DerivedDecl, BaseDecl);
}
bool VtableBuilder::OverrideMethod(GlobalDecl GD, bool MorallyVirtual,
Index_t OverrideOffset, Index_t Offset,
int64_t CurrentVBaseOffset) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
const bool isPure = MD->isPure();
// FIXME: Should OverrideOffset's be Offset?
for (CXXMethodDecl::method_iterator mi = MD->begin_overridden_methods(),
e = MD->end_overridden_methods(); mi != e; ++mi) {
GlobalDecl OGD;
GlobalDecl OGD2;
const CXXMethodDecl *OMD = *mi;
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(OMD))
OGD = GlobalDecl(DD, GD.getDtorType());
else
OGD = OMD;
// Check whether this is the method being overridden in this section of
// the vtable.
uint64_t Index;
if (!Methods.getIndex(OGD, Index))
continue;
OGD2 = OGD;
// Get the original method, which we should be computing thunks, etc,
// against.
OGD = Methods.getOrigMethod(Index);
OMD = cast<CXXMethodDecl>(OGD.getDecl());
QualType ReturnType =
MD->getType()->getAs<FunctionType>()->getResultType();
QualType OverriddenReturnType =
OMD->getType()->getAs<FunctionType>()->getResultType();
// Check if we need a return type adjustment.
if (TypeConversionRequiresAdjustment(CGM.getContext(), ReturnType,
OverriddenReturnType)) {
CanQualType &BaseReturnType = BaseReturnTypes[Index];
// Insert the base return type.
if (BaseReturnType.isNull())
BaseReturnType =
CGM.getContext().getCanonicalType(OverriddenReturnType);
}
Methods.OverrideMethod(OGD, GD);
GlobalDecl UGD = getUnique(GD);
const CXXMethodDecl *UMD = cast<CXXMethodDecl>(UGD.getDecl());
assert(UGD.getDecl() && "unique overrider not found");
assert(UGD == getUnique(OGD) && "unique overrider not unique");
ThisAdjustments.erase(Index);
if (MorallyVirtual || VCall.count(UMD)) {
Index_t &idx = VCall[UMD];
if (idx == 0) {
VCallOffset[GD] = VCallOffset[OGD];
// NonVirtualOffset[UMD] = CurrentVBaseOffset/8 - OverrideOffset/8;
NonVirtualOffset[UMD] = VCallOffset[OGD];
VCallOffsetForVCall[UMD] = OverrideOffset/8;
idx = VCalls.size()+1;
VCalls.push_back(OverrideOffset/8 - CurrentVBaseOffset/8);
D1(printf(" vcall for %s at %d with delta %d most derived %s\n",
MD->getNameAsString().c_str(), (int)-idx-3,
(int)VCalls[idx-1], MostDerivedClass->getNameAsCString()));
} else {
VCallOffset[GD] = NonVirtualOffset[UMD];
VCalls[idx-1] = -VCallOffsetForVCall[UGD] + OverrideOffset/8;
D1(printf(" vcall patch for %s at %d with delta %d most derived %s\n",
MD->getNameAsString().c_str(), (int)-idx-3,
(int)VCalls[idx-1], MostDerivedClass->getNameAsCString()));
}
int64_t NonVirtualAdjustment = -VCallOffset[OGD];
QualType DerivedType = MD->getThisType(CGM.getContext());
QualType BaseType = cast<const CXXMethodDecl>(OGD.getDecl())->getThisType(CGM.getContext());
int64_t NonVirtualAdjustment2 = -(getNVOffset(BaseType, DerivedType)/8);
if (NonVirtualAdjustment2 != NonVirtualAdjustment) {
NonVirtualAdjustment = NonVirtualAdjustment2;
}
int64_t VirtualAdjustment =
-((idx + extra + 2) * LLVMPointerWidth / 8);
// Optimize out virtual adjustments of 0.
if (VCalls[idx-1] == 0)
VirtualAdjustment = 0;
ThunkAdjustment ThisAdjustment(NonVirtualAdjustment,
VirtualAdjustment);
if (!isPure && !ThisAdjustment.isEmpty()) {
ThisAdjustments[Index] = ThisAdjustment;
SavedAdjustments.push_back(
std::make_pair(GD, std::make_pair(OGD, ThisAdjustment)));
}
return true;
}
VCallOffset[GD] = VCallOffset[OGD2] - OverrideOffset/8;
int64_t NonVirtualAdjustment = -VCallOffset[GD];
QualType DerivedType = MD->getThisType(CGM.getContext());
QualType BaseType = cast<const CXXMethodDecl>(OGD.getDecl())->getThisType(CGM.getContext());
int64_t NonVirtualAdjustment2 = -(getNVOffset(BaseType, DerivedType)/8);
if (NonVirtualAdjustment2 != NonVirtualAdjustment) {
NonVirtualAdjustment = NonVirtualAdjustment2;
}
if (NonVirtualAdjustment) {
ThunkAdjustment ThisAdjustment(NonVirtualAdjustment, 0);
if (!isPure) {
ThisAdjustments[Index] = ThisAdjustment;
SavedAdjustments.push_back(
std::make_pair(GD, std::make_pair(OGD, ThisAdjustment)));
}
}
return true;
}
return false;
}
void VtableBuilder::AppendMethodsToVtable() {
if (!BuildVtable) {
VtableComponents.insert(VtableComponents.end(), Methods.size(),
(llvm::Constant *)0);
ThisAdjustments.clear();
BaseReturnTypes.clear();
Methods.clear();
return;
}
// Reserve room in the vtable for our new methods.
VtableComponents.reserve(VtableComponents.size() + Methods.size());
for (unsigned i = 0, e = Methods.size(); i != e; ++i) {
GlobalDecl GD = Methods[i];
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
// Get the 'this' pointer adjustment.
ThunkAdjustment ThisAdjustment = ThisAdjustments.lookup(i);
// Construct the return type adjustment.
ThunkAdjustment ReturnAdjustment;
QualType BaseReturnType = BaseReturnTypes.lookup(i);
if (!BaseReturnType.isNull() && !MD->isPure()) {
QualType DerivedType =
MD->getType()->getAs<FunctionType>()->getResultType();
int64_t NonVirtualAdjustment =
getNVOffset(BaseReturnType, DerivedType) / 8;
int64_t VirtualAdjustment =
getVbaseOffset(BaseReturnType, DerivedType);
ReturnAdjustment = ThunkAdjustment(NonVirtualAdjustment,
VirtualAdjustment);
}
llvm::Constant *Method = 0;
if (!ReturnAdjustment.isEmpty()) {
// Build a covariant thunk.
CovariantThunkAdjustment Adjustment(ThisAdjustment, ReturnAdjustment);
Method = wrap(CGM.GetAddrOfCovariantThunk(GD, Adjustment));
} else if (!ThisAdjustment.isEmpty()) {
// Build a "regular" thunk.
Method = wrap(CGM.GetAddrOfThunk(GD, ThisAdjustment));
} else if (MD->isPure()) {
// We have a pure virtual method.
Method = getPureVirtualFn();
} else {
// We have a good old regular method.
Method = WrapAddrOf(GD);
}
// Add the method to the vtable.
VtableComponents.push_back(Method);
}
ThisAdjustments.clear();
BaseReturnTypes.clear();
Methods.clear();
}
void CGVtableInfo::ComputeMethodVtableIndices(const CXXRecordDecl *RD) {
// Itanium C++ ABI 2.5.2:
// The order of the virtual function pointers in a virtual table is the
// order of declaration of the corresponding member functions in the class.
//
// There is an entry for any virtual function declared in a class,
// whether it is a new function or overrides a base class function,
// unless it overrides a function from the primary base, and conversion
// between their return types does not require an adjustment.
int64_t CurrentIndex = 0;
const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
if (PrimaryBase) {
assert(PrimaryBase->isDefinition() &&
"Should have the definition decl of the primary base!");
// Since the record decl shares its vtable pointer with the primary base
// we need to start counting at the end of the primary base's vtable.
CurrentIndex = getNumVirtualFunctionPointers(PrimaryBase);
}
// Collect all the primary bases, so we can check whether methods override
// a method from the base.
llvm::SmallPtrSet<const CXXRecordDecl *, 5> PrimaryBases;
for (ASTRecordLayout::primary_base_info_iterator
I = Layout.primary_base_begin(), E = Layout.primary_base_end();
I != E; ++I)
PrimaryBases.insert((*I).getBase());
const CXXDestructorDecl *ImplicitVirtualDtor = 0;
for (CXXRecordDecl::method_iterator i = RD->method_begin(),
e = RD->method_end(); i != e; ++i) {
const CXXMethodDecl *MD = *i;
// We only want virtual methods.
if (!MD->isVirtual())
continue;
bool ShouldAddEntryForMethod = true;
// Check if this method overrides a method in the primary base.
for (CXXMethodDecl::method_iterator i = MD->begin_overridden_methods(),
e = MD->end_overridden_methods(); i != e; ++i) {
const CXXMethodDecl *OverriddenMD = *i;
const CXXRecordDecl *OverriddenRD = OverriddenMD->getParent();
assert(OverriddenMD->isCanonicalDecl() &&
"Should have the canonical decl of the overridden RD!");
if (PrimaryBases.count(OverriddenRD)) {
// Check if converting from the return type of the method to the
// return type of the overridden method requires conversion.
QualType ReturnType =
MD->getType()->getAs<FunctionType>()->getResultType();
QualType OverriddenReturnType =
OverriddenMD->getType()->getAs<FunctionType>()->getResultType();
if (!TypeConversionRequiresAdjustment(CGM.getContext(),
ReturnType, OverriddenReturnType)) {
// This index is shared between the index in the vtable of the primary
// base class.
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
const CXXDestructorDecl *OverriddenDD =
cast<CXXDestructorDecl>(OverriddenMD);
// Add both the complete and deleting entries.
MethodVtableIndices[GlobalDecl(DD, Dtor_Complete)] =
getMethodVtableIndex(GlobalDecl(OverriddenDD, Dtor_Complete));
MethodVtableIndices[GlobalDecl(DD, Dtor_Deleting)] =
getMethodVtableIndex(GlobalDecl(OverriddenDD, Dtor_Deleting));
} else {
MethodVtableIndices[MD] = getMethodVtableIndex(OverriddenMD);
}
// We don't need to add an entry for this method.
ShouldAddEntryForMethod = false;
break;
}
}
}
if (!ShouldAddEntryForMethod)
continue;
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
if (MD->isImplicit()) {
assert(!ImplicitVirtualDtor &&
"Did already see an implicit virtual dtor!");
ImplicitVirtualDtor = DD;
continue;
}
// Add the complete dtor.
MethodVtableIndices[GlobalDecl(DD, Dtor_Complete)] = CurrentIndex++;
// Add the deleting dtor.
MethodVtableIndices[GlobalDecl(DD, Dtor_Deleting)] = CurrentIndex++;
} else {
// Add the entry.
MethodVtableIndices[MD] = CurrentIndex++;
}
}
if (ImplicitVirtualDtor) {
// Itanium C++ ABI 2.5.2:
// If a class has an implicitly-defined virtual destructor,
// its entries come after the declared virtual function pointers.
// Add the complete dtor.
MethodVtableIndices[GlobalDecl(ImplicitVirtualDtor, Dtor_Complete)] =
CurrentIndex++;
// Add the deleting dtor.
MethodVtableIndices[GlobalDecl(ImplicitVirtualDtor, Dtor_Deleting)] =
CurrentIndex++;
}
NumVirtualFunctionPointers[RD] = CurrentIndex;
}
uint64_t CGVtableInfo::getNumVirtualFunctionPointers(const CXXRecordDecl *RD) {
llvm::DenseMap<const CXXRecordDecl *, uint64_t>::iterator I =
NumVirtualFunctionPointers.find(RD);
if (I != NumVirtualFunctionPointers.end())
return I->second;
ComputeMethodVtableIndices(RD);
I = NumVirtualFunctionPointers.find(RD);
assert(I != NumVirtualFunctionPointers.end() && "Did not find entry!");
return I->second;
}
uint64_t CGVtableInfo::getMethodVtableIndex(GlobalDecl GD) {
MethodVtableIndicesTy::iterator I = MethodVtableIndices.find(GD);
if (I != MethodVtableIndices.end())
return I->second;
const CXXRecordDecl *RD = cast<CXXMethodDecl>(GD.getDecl())->getParent();
ComputeMethodVtableIndices(RD);
I = MethodVtableIndices.find(GD);
assert(I != MethodVtableIndices.end() && "Did not find index!");
return I->second;
}
CGVtableInfo::AdjustmentVectorTy*
CGVtableInfo::getAdjustments(GlobalDecl GD) {
SavedAdjustmentsTy::iterator I = SavedAdjustments.find(GD);
if (I != SavedAdjustments.end())
return &I->second;
const CXXRecordDecl *RD = cast<CXXRecordDecl>(GD.getDecl()->getDeclContext());
if (!SavedAdjustmentRecords.insert(RD).second)
return 0;
AddressPointsMapTy AddressPoints;
VtableBuilder b(RD, RD, 0, CGM, false, AddressPoints);
D1(printf("vtable %s\n", RD->getNameAsCString()));
b.GenerateVtableForBase(RD);
b.GenerateVtableForVBases(RD);
for (VtableBuilder::SavedAdjustmentsVectorTy::iterator
i = b.getSavedAdjustments().begin(),
e = b.getSavedAdjustments().end(); i != e; i++)
SavedAdjustments[i->first].push_back(i->second);
I = SavedAdjustments.find(GD);
if (I != SavedAdjustments.end())
return &I->second;
return 0;
}
int64_t CGVtableInfo::getVirtualBaseOffsetIndex(const CXXRecordDecl *RD,
const CXXRecordDecl *VBase) {
ClassPairTy ClassPair(RD, VBase);
VirtualBaseClassIndiciesTy::iterator I =
VirtualBaseClassIndicies.find(ClassPair);
if (I != VirtualBaseClassIndicies.end())
return I->second;
// FIXME: This seems expensive. Can we do a partial job to get
// just this data.
AddressPointsMapTy AddressPoints;
VtableBuilder b(RD, RD, 0, CGM, false, AddressPoints);
D1(printf("vtable %s\n", RD->getNameAsCString()));
b.GenerateVtableForBase(RD);
b.GenerateVtableForVBases(RD);
for (llvm::DenseMap<const CXXRecordDecl *, uint64_t>::iterator I =
b.getVBIndex().begin(), E = b.getVBIndex().end(); I != E; ++I) {
// Insert all types.
ClassPairTy ClassPair(RD, I->first);
VirtualBaseClassIndicies.insert(std::make_pair(ClassPair, I->second));
}
I = VirtualBaseClassIndicies.find(ClassPair);
assert(I != VirtualBaseClassIndicies.end() && "Did not find index!");
return I->second;
}
uint64_t CGVtableInfo::getVtableAddressPoint(const CXXRecordDecl *RD) {
uint64_t AddressPoint =
(*(*(CGM.getVtableInfo().AddressPoints[RD]))[RD])[std::make_pair(RD, 0)];
return AddressPoint;
}
llvm::GlobalVariable *
CGVtableInfo::GenerateVtable(llvm::GlobalVariable::LinkageTypes Linkage,
bool GenerateDefinition,
const CXXRecordDecl *LayoutClass,
const CXXRecordDecl *RD, uint64_t Offset,
AddressPointsMapTy& AddressPoints) {
llvm::SmallString<256> OutName;
if (LayoutClass != RD)
CGM.getMangleContext().mangleCXXCtorVtable(LayoutClass, Offset / 8,
RD, OutName);
else
CGM.getMangleContext().mangleCXXVtable(RD, OutName);
llvm::StringRef Name = OutName.str();
llvm::GlobalVariable *GV = CGM.getModule().getGlobalVariable(Name);
if (GV == 0 || CGM.getVtableInfo().AddressPoints[LayoutClass] == 0 ||
GV->isDeclaration()) {
VtableBuilder b(RD, LayoutClass, Offset, CGM, GenerateDefinition,
AddressPoints);
D1(printf("vtable %s\n", RD->getNameAsCString()));
// First comes the vtables for all the non-virtual bases...
b.GenerateVtableForBase(RD, Offset);
// then the vtables for all the virtual bases.
b.GenerateVtableForVBases(RD, Offset);
llvm::Constant *Init = 0;
const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
llvm::ArrayType *ArrayType =
llvm::ArrayType::get(Int8PtrTy, b.getVtableComponents().size());
if (GenerateDefinition)
Init = llvm::ConstantArray::get(ArrayType, &b.getVtableComponents()[0],
b.getVtableComponents().size());
llvm::GlobalVariable *OGV = GV;
GV = new llvm::GlobalVariable(CGM.getModule(), ArrayType,
/*isConstant=*/true, Linkage, Init, Name);
CGM.setGlobalVisibility(GV, RD);
if (OGV) {
GV->takeName(OGV);
llvm::Constant *NewPtr =
llvm::ConstantExpr::getBitCast(GV, OGV->getType());
OGV->replaceAllUsesWith(NewPtr);
OGV->eraseFromParent();
}
}
return GV;
}
void CGVtableInfo::GenerateClassData(llvm::GlobalVariable::LinkageTypes Linkage,
const CXXRecordDecl *RD) {
llvm::GlobalVariable *&Vtable = Vtables[RD];
if (Vtable) {
assert(Vtable->getInitializer() && "Vtable doesn't have a definition!");
return;
}
AddressPointsMapTy AddressPoints;
Vtable = GenerateVtable(Linkage, /*GenerateDefinition=*/true, RD, RD, 0,
AddressPoints);
GenerateVTT(Linkage, /*GenerateDefinition=*/true, RD);
}
llvm::GlobalVariable *CGVtableInfo::getVtable(const CXXRecordDecl *RD) {
llvm::GlobalVariable *Vtable = Vtables.lookup(RD);
if (!Vtable) {
AddressPointsMapTy AddressPoints;
Vtable = GenerateVtable(llvm::GlobalValue::ExternalLinkage,
/*GenerateDefinition=*/false, RD, RD, 0,
AddressPoints);
}
return Vtable;
}
void CGVtableInfo::MaybeEmitVtable(GlobalDecl GD) {
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
const CXXRecordDecl *RD = MD->getParent();
// If the class doesn't have a vtable we don't need to emit one.
if (!RD->isDynamicClass())
return;
// Get the key function.
const CXXMethodDecl *KeyFunction = CGM.getContext().getKeyFunction(RD);
if (KeyFunction) {
// We don't have the right key function.
if (KeyFunction->getCanonicalDecl() != MD->getCanonicalDecl())
return;
}
// Emit the data.
GenerateClassData(CGM.getVtableLinkage(RD), RD);
for (CXXRecordDecl::method_iterator i = RD->method_begin(),
e = RD->method_end(); i != e; ++i) {
if ((*i)->isVirtual() && ((*i)->hasInlineBody() || (*i)->isImplicit())) {
if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(*i)) {
CGM.BuildThunksForVirtual(GlobalDecl(DD, Dtor_Complete));
CGM.BuildThunksForVirtual(GlobalDecl(DD, Dtor_Deleting));
} else {
CGM.BuildThunksForVirtual(GlobalDecl(*i));
}
}
}
}