Fix PR17738 - add support for vtordisp thunks when using -cxx-abi microsoft
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@194132 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/VTableBuilder.cpp b/lib/AST/VTableBuilder.cpp
index 69a2fb2..efaa313 100644
--- a/lib/AST/VTableBuilder.cpp
+++ b/lib/AST/VTableBuilder.cpp
@@ -1304,7 +1304,7 @@
VCallOffsets = Builder.getVCallOffsets();
}
- Adjustment.VCallOffsetOffset =
+ Adjustment.Virtual.Itanium.VCallOffsetOffset =
VCallOffsets.getVCallOffsetOffset(MD).getQuantity();
}
@@ -1552,7 +1552,7 @@
ComputeThisAdjustment(OverriddenMD, BaseOffsetInLayoutClass,
Overrider);
- if (ThisAdjustment.VCallOffsetOffset &&
+ if (ThisAdjustment.Virtual.Itanium.VCallOffsetOffset &&
Overrider.Method->getParent() == MostDerivedClass) {
// There's no return adjustment from OverriddenMD and MD,
@@ -2009,8 +2009,8 @@
Out << "\n [this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
- if (Thunk.This.VCallOffsetOffset) {
- Out << ", " << Thunk.This.VCallOffsetOffset;
+ if (Thunk.This.Virtual.Itanium.VCallOffsetOffset) {
+ Out << ", " << Thunk.This.Virtual.Itanium.VCallOffsetOffset;
Out << " vcall offset offset";
}
@@ -2044,8 +2044,8 @@
Out << "\n [this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
- if (Thunk.This.VCallOffsetOffset) {
- Out << ", " << Thunk.This.VCallOffsetOffset;
+ if (Thunk.This.Virtual.Itanium.VCallOffsetOffset) {
+ Out << ", " << Thunk.This.Virtual.Itanium.VCallOffsetOffset;
Out << " vcall offset offset";
}
@@ -2186,8 +2186,8 @@
Out << "this adjustment: ";
Out << Thunk.This.NonVirtual << " non-virtual";
- if (Thunk.This.VCallOffsetOffset) {
- Out << ", " << Thunk.This.VCallOffsetOffset;
+ if (Thunk.This.Virtual.Itanium.VCallOffsetOffset) {
+ Out << ", " << Thunk.This.Virtual.Itanium.VCallOffsetOffset;
Out << " vcall offset offset";
}
}
@@ -2527,6 +2527,9 @@
BaseSubobject Base,
FinalOverriders::OverriderInfo Overrider);
+ void CalculateVtordispAdjustment(FinalOverriders::OverriderInfo Overrider,
+ CharUnits ThisOffset, ThisAdjustment &TA);
+
/// AddMethod - Add a single virtual member function to the vftable
/// components vector.
void AddMethod(const CXXMethodDecl *MD, ThunkInfo TI) {
@@ -2672,7 +2675,7 @@
I != E; ++I) {
const CXXBasePath &Path = (*I);
CharUnits ThisOffset = Base.getBaseOffset();
- bool SeenVBase = false;
+ CharUnits LastVBaseOffset;
// For each path from the overrider to the parents of the overridden methods,
// traverse the path, calculating the this offset in the most derived class.
@@ -2684,7 +2687,7 @@
const ASTRecordLayout &Layout = Context.getASTRecordLayout(PrevRD);
if (Element.Base->isVirtual()) {
- SeenVBase = true;
+ LastVBaseOffset = MostDerivedClassLayout.getVBaseClassOffset(CurRD);
if (Overrider.Method->getParent() == PrevRD) {
// This one's interesting. If the final overrider is in a vbase B of the
// most derived class and it overrides a method of the B's own vbase A,
@@ -2695,23 +2698,25 @@
// differently in the most derived class.
ThisOffset += Layout.getVBaseClassOffset(CurRD);
} else {
- ThisOffset = MostDerivedClassLayout.getVBaseClassOffset(CurRD);
+ ThisOffset = LastVBaseOffset;
}
-
- // A virtual destructor of a virtual base takes the address of the
- // virtual base subobject as the "this" argument.
- if (isa<CXXDestructorDecl>(MD))
- break;
} else {
ThisOffset += Layout.getBaseClassOffset(CurRD);
}
}
- // If a "Base" class has at least one non-virtual base with a virtual
- // destructor, the "Base" virtual destructor will take the address of the
- // "Base" subobject as the "this" argument.
- if (!SeenVBase && isa<CXXDestructorDecl>(MD))
- return Base.getBaseOffset();
+ if (isa<CXXDestructorDecl>(MD)) {
+ if (LastVBaseOffset.isZero()) {
+ // If a "Base" class has at least one non-virtual base with a virtual
+ // destructor, the "Base" virtual destructor will take the address
+ // of the "Base" subobject as the "this" argument.
+ return Base.getBaseOffset();
+ } else {
+ // A virtual destructor of a virtual base takes the address of the
+ // virtual base subobject as the "this" argument.
+ return LastVBaseOffset;
+ }
+ }
if (Ret > ThisOffset || First) {
First = false;
@@ -2723,6 +2728,49 @@
return Ret;
}
+void VFTableBuilder::CalculateVtordispAdjustment(
+ FinalOverriders::OverriderInfo Overrider, CharUnits ThisOffset,
+ ThisAdjustment &TA) {
+ const ASTRecordLayout::VBaseOffsetsMapTy &VBaseMap =
+ MostDerivedClassLayout.getVBaseOffsetsMap();
+ const ASTRecordLayout::VBaseOffsetsMapTy::const_iterator &VBaseMapEntry =
+ VBaseMap.find(WhichVFPtr.LastVBase);
+ assert(VBaseMapEntry != VBaseMap.end());
+
+ // Check if we need a vtordisp adjustment at all.
+ if (!VBaseMapEntry->second.hasVtorDisp())
+ return;
+
+ CharUnits VFPtrVBaseOffset = VBaseMapEntry->second.VBaseOffset;
+ // The implicit vtordisp field is located right before the vbase.
+ TA.Virtual.Microsoft.VtordispOffset =
+ (VFPtrVBaseOffset - WhichVFPtr.VFPtrFullOffset).getQuantity() - 4;
+
+ // If the final overrider is defined in either:
+ // - the most derived class or its non-virtual base or
+ // - the same vbase as the initial declaration,
+ // a simple vtordisp thunk will suffice.
+ const CXXRecordDecl *OverriderRD = Overrider.Method->getParent();
+ if (OverriderRD == MostDerivedClass)
+ return;
+
+ const CXXRecordDecl *OverriderVBase =
+ ComputeBaseOffset(Context, OverriderRD, MostDerivedClass).VirtualBase;
+ if (!OverriderVBase || OverriderVBase == WhichVFPtr.LastVBase)
+ return;
+
+ // Otherwise, we need to do use the dynamic offset of the final overrider
+ // in order to get "this" adjustment right.
+ TA.Virtual.Microsoft.VBPtrOffset =
+ (VFPtrVBaseOffset + WhichVFPtr.VFPtrOffset -
+ MostDerivedClassLayout.getVBPtrOffset()).getQuantity();
+ TA.Virtual.Microsoft.VBOffsetOffset =
+ Context.getTypeSizeInChars(Context.IntTy).getQuantity() *
+ VTables.getVBTableIndex(MostDerivedClass, OverriderVBase);
+
+ TA.NonVirtual = (ThisOffset - Overrider.Offset).getQuantity();
+}
+
static void GroupNewVirtualOverloads(
const CXXRecordDecl *RD,
SmallVector<const CXXMethodDecl *, 10> &VirtualMethods) {
@@ -2829,6 +2877,12 @@
if (TI != WhichVFPtr.VFPtrFullOffset) {
ThisAdjustmentOffset.NonVirtual =
(TI - WhichVFPtr.VFPtrFullOffset).getQuantity();
+ }
+
+ if (WhichVFPtr.LastVBase)
+ CalculateVtordispAdjustment(Overrider, TI, ThisAdjustmentOffset);
+
+ if (!ThisAdjustmentOffset.isEmpty()) {
VTableThunks[OverriddenMethodInfo.VFTableIndex].This =
ThisAdjustmentOffset;
AddThunk(MD, VTableThunks[OverriddenMethodInfo.VFTableIndex]);
@@ -2962,8 +3016,17 @@
if (Multiline || !ContinueFirstLine)
Out << LinePrefix;
Out << "[this adjustment: ";
- assert(TI.This.VCallOffsetOffset == 0 &&
- "VtorDisp adjustment is not supported yet");
+ if (!TI.This.Virtual.isEmpty()) {
+ assert(T.Virtual.Microsoft.VtordispOffset < 0);
+ Out << "vtordisp at " << T.Virtual.Microsoft.VtordispOffset << ", ";
+ if (T.Virtual.Microsoft.VBPtrOffset) {
+ Out << "vbptr at " << T.Virtual.Microsoft.VBPtrOffset
+ << " to the left, ";
+ assert(T.Virtual.Microsoft.VBOffsetOffset > 0);
+ Out << LinePrefix << " vboffset at "
+ << T.Virtual.Microsoft.VBOffsetOffset << " in the vbtable, ";
+ }
+ }
Out << T.NonVirtual << " non-virtual]";
}
}