Work in progress for setting the vtable pointers for all bases correctly in
the constructor. This doesn't handle cases requiring the VTT at the moment,
and generates unnecessary stores, but I think it's essentially correct.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@91731 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index e860c29..0237a32 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -1700,21 +1700,65 @@
void CodeGenFunction::InitializeVtablePtrs(const CXXRecordDecl *ClassDecl) {
if (!ClassDecl->isDynamicClass())
return;
-
- // Initialize the vtable pointer.
- // FIXME: This needs to initialize secondary vtable pointers too.
- llvm::Value *ThisPtr = LoadCXXThis();
llvm::Constant *Vtable = CGM.getVtableInfo().getVtable(ClassDecl);
- uint64_t AddressPoint = CGM.getVtableInfo().getVtableAddressPoint(ClassDecl);
+ CodeGenModule::AddrSubMap_t& AddressPoints =
+ *(*CGM.AddressPoints[ClassDecl])[ClassDecl];
+ llvm::Value *ThisPtr = LoadCXXThis();
+ const ASTRecordLayout &Layout = getContext().getASTRecordLayout(ClassDecl);
+ // Store address points for virtual bases
+ for (CXXRecordDecl::base_class_const_iterator I =
+ ClassDecl->vbases_begin(), E = ClassDecl->vbases_end(); I != E; ++I) {
+ const CXXBaseSpecifier &Base = *I;
+ CXXRecordDecl *BaseClassDecl
+ = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
+ uint64_t Offset = Layout.getVBaseClassOffset(BaseClassDecl);
+ InitializeVtablePtrsRecursive(BaseClassDecl, Vtable, AddressPoints,
+ ThisPtr, Offset);
+ }
+
+ // Store address points for non-virtual bases and current class
+ InitializeVtablePtrsRecursive(ClassDecl, Vtable, AddressPoints, ThisPtr, 0);
+}
+
+void CodeGenFunction::InitializeVtablePtrsRecursive(
+ const CXXRecordDecl *ClassDecl,
+ llvm::Constant *Vtable,
+ CodeGenModule::AddrSubMap_t& AddressPoints,
+ llvm::Value *ThisPtr,
+ uint64_t Offset) {
+ if (!ClassDecl->isDynamicClass())
+ return;
+
+ // Store address points for non-virtual bases
+ const ASTRecordLayout &Layout = getContext().getASTRecordLayout(ClassDecl);
+ for (CXXRecordDecl::base_class_const_iterator I =
+ ClassDecl->bases_begin(), E = ClassDecl->bases_end(); I != E; ++I) {
+ const CXXBaseSpecifier &Base = *I;
+ if (Base.isVirtual())
+ continue;
+ CXXRecordDecl *BaseClassDecl
+ = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
+ uint64_t NewOffset = Offset + Layout.getBaseClassOffset(BaseClassDecl);
+ InitializeVtablePtrsRecursive(BaseClassDecl, Vtable, AddressPoints,
+ ThisPtr, NewOffset);
+ }
+
+ // Compute the address point
+ uint64_t AddressPoint = AddressPoints[std::make_pair(ClassDecl, Offset)];
llvm::Value *VtableAddressPoint =
- Builder.CreateConstInBoundsGEP2_64(Vtable, 0, AddressPoint);
-
- llvm::Value *VtableField =
- Builder.CreateBitCast(ThisPtr,
- VtableAddressPoint->getType()->getPointerTo());
-
+ Builder.CreateConstInBoundsGEP2_64(Vtable, 0, AddressPoint);
+
+ // Compute the address to store the address point
+ const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
+ llvm::Value *VtableField = Builder.CreateBitCast(ThisPtr, Int8PtrTy);
+ VtableField = Builder.CreateConstInBoundsGEP1_64(VtableField, Offset/8);
+ const llvm::Type *AddressPointPtrTy =
+ VtableAddressPoint->getType()->getPointerTo();
+ VtableField = Builder.CreateBitCast(ThisPtr, AddressPointPtrTy);
+
+ // Store address point
Builder.CreateStore(VtableAddressPoint, VtableField);
}
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 4bacd16..c2e59c0 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -515,6 +515,12 @@
void InitializeVtablePtrs(const CXXRecordDecl *ClassDecl);
+ void InitializeVtablePtrsRecursive(const CXXRecordDecl *ClassDecl,
+ llvm::Constant *Vtable,
+ CodeGenModule::AddrSubMap_t& AddressPoints,
+ llvm::Value *ThisPtr,
+ uint64_t Offset);
+
void SynthesizeCXXCopyConstructor(const CXXConstructorDecl *Ctor,
CXXCtorType Type,
llvm::Function *Fn,
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index 814b1ef..939c66c 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -233,8 +233,8 @@
const CovariantThunkAdjustment &Adjustment);
typedef std::pair<const CXXRecordDecl *, uint64_t> CtorVtable_t;
- typedef llvm::DenseMap<const CXXRecordDecl *,
- llvm::DenseMap<CtorVtable_t, int64_t>*> AddrMap_t;
+ typedef llvm::DenseMap<CtorVtable_t, int64_t> AddrSubMap_t;
+ typedef llvm::DenseMap<const CXXRecordDecl *, AddrSubMap_t *> AddrMap_t;
llvm::DenseMap<const CXXRecordDecl *, AddrMap_t*> AddressPoints;
/// GetCXXBaseClassOffset - Returns the offset from a derived class to its