[-cxx-abi microsoft] Fix this argument/parameter offsets for virtual destructors in the presence of virtual bases
Reviewed at http://llvm-reviews.chandlerc.com/D1939
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@192822 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGClass.cpp b/lib/CodeGen/CGClass.cpp
index 91f42e2..d690784 100644
--- a/lib/CodeGen/CGClass.cpp
+++ b/lib/CodeGen/CGClass.cpp
@@ -1829,8 +1829,8 @@
bool ForVirtualBase,
bool Delegating,
llvm::Value *This) {
- llvm::Value *VTT = GetVTTParameter(GlobalDecl(DD, Type),
- ForVirtualBase, Delegating);
+ GlobalDecl GD(DD, Type);
+ llvm::Value *VTT = GetVTTParameter(GD, ForVirtualBase, Delegating);
llvm::Value *Callee = 0;
if (getLangOpts().AppleKext)
Callee = BuildAppleKextVirtualDestructorCall(DD, Type,
@@ -1838,7 +1838,10 @@
if (!Callee)
Callee = CGM.GetAddrOfCXXDestructor(DD, Type);
-
+
+ if (DD->isVirtual())
+ This = CGM.getCXXABI().adjustThisArgumentForVirtualCall(*this, GD, This);
+
// FIXME: Provide a source location here.
EmitCXXMemberCall(DD, SourceLocation(), Callee, ReturnValueSlot(), This,
VTT, getContext().getPointerType(getContext().VoidPtrTy),
diff --git a/lib/CodeGen/MicrosoftCXXABI.cpp b/lib/CodeGen/MicrosoftCXXABI.cpp
index 9d59160..c1ea60d 100644
--- a/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -563,21 +563,65 @@
CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) {
GD = GD.getCanonicalDecl();
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
- if (isa<CXXDestructorDecl>(MD))
- return This;
+ // FIXME: consider splitting the vdtor vs regular method code into two
+ // functions.
+ GlobalDecl LookupGD = GD;
+ if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
+ // Complete dtors take a pointer to the complete object,
+ // thus don't need adjustment.
+ if (GD.getDtorType() == Dtor_Complete)
+ return This;
+
+ // There's only Dtor_Deleting in vftable but it shares the this adjustment
+ // with the base one, so look up the deleting one instead.
+ LookupGD = GlobalDecl(DD, Dtor_Deleting);
+ }
MicrosoftVFTableContext::MethodVFTableLocation ML =
- CGM.getVFTableContext().getMethodVFTableLocation(GD);
+ CGM.getVFTableContext().getMethodVFTableLocation(LookupGD);
unsigned AS = cast<llvm::PointerType>(This->getType())->getAddressSpace();
llvm::Type *charPtrTy = CGF.Int8Ty->getPointerTo(AS);
- if (ML.VBase) {
- This = CGF.Builder.CreateBitCast(This, charPtrTy);
- llvm::Value *VBaseOffset = CGM.getCXXABI()
- .GetVirtualBaseClassOffset(CGF, This, MD->getParent(), ML.VBase);
- This = CGF.Builder.CreateInBoundsGEP(This, VBaseOffset);
- }
CharUnits StaticOffset = ML.VFTableOffset;
+ if (ML.VBase) {
+ bool AvoidVirtualOffset = false;
+ if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base) {
+ // A base destructor can only be called from a complete destructor of the
+ // same record type or another destructor of a more derived type.
+ const CXXRecordDecl *CurRD =
+ cast<CXXDestructorDecl>(CGF.CurGD.getDecl())->getParent();
+
+ if (MD->getParent() == CurRD) {
+ assert(CGF.CurGD.getDtorType() == Dtor_Complete);
+ // We're calling the main base dtor from a complete dtor, so we know the
+ // "this" offset statically.
+ AvoidVirtualOffset = true;
+ } else {
+ // Let's see if we try to call a destructor of a non-virtual base.
+ for (CXXRecordDecl::base_class_const_iterator I = CurRD->bases_begin(),
+ E = CurRD->bases_end(); I != E; ++I) {
+ if (I->getType()->getAsCXXRecordDecl() != MD->getParent())
+ continue;
+ // If we call a base destructor for a non-virtual base, we statically
+ // know where it expects the vfptr and "this" to be.
+ AvoidVirtualOffset = true;
+ break;
+ }
+ }
+ }
+
+ if (AvoidVirtualOffset) {
+ const ASTRecordLayout &Layout =
+ CGF.getContext().getASTRecordLayout(MD->getParent());
+ // This reflects the logic from VFTableBuilder::ComputeThisOffset().
+ StaticOffset += Layout.getVBaseClassOffset(ML.VBase);
+ } else {
+ This = CGF.Builder.CreateBitCast(This, charPtrTy);
+ llvm::Value *VBaseOffset = CGM.getCXXABI()
+ .GetVirtualBaseClassOffset(CGF, This, MD->getParent(), ML.VBase);
+ This = CGF.Builder.CreateInBoundsGEP(This, VBaseOffset);
+ }
+ }
if (!StaticOffset.isZero()) {
assert(StaticOffset.isPositive());
This = CGF.Builder.CreateBitCast(This, charPtrTy);
@@ -625,8 +669,18 @@
CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) {
GD = GD.getCanonicalDecl();
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
- if (isa<CXXDestructorDecl>(MD))
- return This;
+
+ GlobalDecl LookupGD = GD;
+ if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
+ // Complete destructors take a pointer to the complete object as a
+ // parameter, thus don't need this adjustment.
+ if (GD.getDtorType() == Dtor_Complete)
+ return This;
+
+ // There's no Dtor_Base in vftable but it shares the this adjustment with
+ // the deleting one, so look it up instead.
+ LookupGD = GlobalDecl(DD, Dtor_Deleting);
+ }
// In this ABI, every virtual function takes a pointer to one of the
// subobjects that first defines it as the 'this' parameter, rather than a
@@ -635,7 +689,7 @@
// See comments in the MicrosoftVFTableContext implementation for the details.
MicrosoftVFTableContext::MethodVFTableLocation ML =
- CGM.getVFTableContext().getMethodVFTableLocation(GD);
+ CGM.getVFTableContext().getMethodVFTableLocation(LookupGD);
CharUnits Adjustment = ML.VFTableOffset;
if (ML.VBase) {
const ASTRecordLayout &DerivedLayout =
@@ -850,17 +904,18 @@
// We have only one destructor in the vftable but can get both behaviors
// by passing an implicit int parameter.
+ GlobalDecl GD(Dtor, Dtor_Deleting);
const CGFunctionInfo *FInfo =
&CGM.getTypes().arrangeCXXDestructor(Dtor, Dtor_Deleting);
llvm::Type *Ty = CGF.CGM.getTypes().GetFunctionType(*FInfo);
- llvm::Value *Callee =
- getVirtualFunctionPointer(CGF, GlobalDecl(Dtor, Dtor_Deleting), This, Ty);
+ llvm::Value *Callee = getVirtualFunctionPointer(CGF, GD, This, Ty);
ASTContext &Context = CGF.getContext();
llvm::Value *ImplicitParam =
llvm::ConstantInt::get(llvm::IntegerType::getInt32Ty(CGF.getLLVMContext()),
DtorType == Dtor_Deleting);
+ This = adjustThisArgumentForVirtualCall(CGF, GD, This);
CGF.EmitCXXMemberCall(Dtor, CallLoc, Callee, ReturnValueSlot(), This,
ImplicitParam, Context.IntTy, 0, 0);
}