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[Clang][CodeGen] Fix this argument type for certain destructors
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With the Microsoft ABI, some destructors need to offset a parameter to
get the derived this pointer, in which case the type of that parameter
should not be a pointer to the derived type.

Fixes #60465
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jacobly0 authored and efriedma-quic committed Mar 1, 2023
1 parent e8a2fd5 commit 6740991
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Showing 9 changed files with 96 additions and 57 deletions.
3 changes: 3 additions & 0 deletions clang/docs/ReleaseNotes.rst
Expand Up @@ -275,6 +275,9 @@ libclang

Static Analyzer
---------------
- Fix incorrect alignment attribute on the this parameter of certain
non-complete destructors when using the Microsoft ABI.
`Issue 60465 <https://github.com/llvm/llvm-project/issues/60465>`_.

.. _release-notes-sanitizers:

Expand Down
5 changes: 2 additions & 3 deletions clang/lib/CodeGen/CGCXXABI.h
Expand Up @@ -379,9 +379,8 @@ class CGCXXABI {
/// zero if no specific type is applicable, e.g. if the ABI expects the "this"
/// parameter to point to some artificial offset in a complete object due to
/// vbases being reordered.
virtual const CXXRecordDecl *
getThisArgumentTypeForMethod(const CXXMethodDecl *MD) {
return MD->getParent();
virtual const CXXRecordDecl *getThisArgumentTypeForMethod(GlobalDecl GD) {
return cast<CXXMethodDecl>(GD.getDecl())->getParent();
}

/// Perform ABI-specific "this" argument adjustment required prior to
Expand Down
4 changes: 3 additions & 1 deletion clang/lib/CodeGen/CGCall.cpp
Expand Up @@ -321,7 +321,9 @@ CodeGenTypes::arrangeCXXStructorDeclaration(GlobalDecl GD) {

SmallVector<CanQualType, 16> argTypes;
SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
argTypes.push_back(DeriveThisType(MD->getParent(), MD));

const CXXRecordDecl *ThisType = TheCXXABI.getThisArgumentTypeForMethod(GD);
argTypes.push_back(DeriveThisType(ThisType, MD));

bool PassParams = true;

Expand Down
11 changes: 7 additions & 4 deletions clang/lib/CodeGen/CGExprCXX.cpp
Expand Up @@ -33,18 +33,20 @@ struct MemberCallInfo {
}

static MemberCallInfo
commonEmitCXXMemberOrOperatorCall(CodeGenFunction &CGF, const CXXMethodDecl *MD,
commonEmitCXXMemberOrOperatorCall(CodeGenFunction &CGF, GlobalDecl GD,
llvm::Value *This, llvm::Value *ImplicitParam,
QualType ImplicitParamTy, const CallExpr *CE,
CallArgList &Args, CallArgList *RtlArgs) {
auto *MD = cast<CXXMethodDecl>(GD.getDecl());

assert(CE == nullptr || isa<CXXMemberCallExpr>(CE) ||
isa<CXXOperatorCallExpr>(CE));
assert(MD->isInstance() &&
"Trying to emit a member or operator call expr on a static method!");

// Push the this ptr.
const CXXRecordDecl *RD =
CGF.CGM.getCXXABI().getThisArgumentTypeForMethod(MD);
CGF.CGM.getCXXABI().getThisArgumentTypeForMethod(GD);
Args.add(RValue::get(This), CGF.getTypes().DeriveThisType(RD, MD));

// If there is an implicit parameter (e.g. VTT), emit it.
Expand Down Expand Up @@ -110,7 +112,7 @@ RValue CodeGenFunction::EmitCXXDestructorCall(
}

CallArgList Args;
commonEmitCXXMemberOrOperatorCall(*this, DtorDecl, This, ImplicitParam,
commonEmitCXXMemberOrOperatorCall(*this, Dtor, This, ImplicitParam,
ImplicitParamTy, CE, Args, nullptr);
return EmitCall(CGM.getTypes().arrangeCXXStructorDeclaration(Dtor), Callee,
ReturnValueSlot(), Args, nullptr, CE && CE == MustTailCall,
Expand Down Expand Up @@ -285,7 +287,8 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
assert(ReturnValue.isNull() && "Constructor shouldn't have return value");
CallArgList Args;
commonEmitCXXMemberOrOperatorCall(
*this, Ctor, This.getPointer(*this), /*ImplicitParam=*/nullptr,
*this, {Ctor, Ctor_Complete}, This.getPointer(*this),
/*ImplicitParam=*/nullptr,
/*ImplicitParamTy=*/QualType(), CE, Args, nullptr);

EmitCXXConstructorCall(Ctor, Ctor_Complete, /*ForVirtualBase=*/false,
Expand Down
21 changes: 17 additions & 4 deletions clang/lib/CodeGen/MicrosoftCXXABI.cpp
Expand Up @@ -235,11 +235,24 @@ class MicrosoftCXXABI : public CGCXXABI {

void EmitCXXDestructors(const CXXDestructorDecl *D) override;

const CXXRecordDecl *
getThisArgumentTypeForMethod(const CXXMethodDecl *MD) override {
if (MD->isVirtual() && !isa<CXXDestructorDecl>(MD)) {
const CXXRecordDecl *getThisArgumentTypeForMethod(GlobalDecl GD) override {
auto *MD = cast<CXXMethodDecl>(GD.getDecl());

if (MD->isVirtual()) {
GlobalDecl LookupGD = GD;
if (const auto *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 MD->getParent();

// 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);
}
MethodVFTableLocation ML =
CGM.getMicrosoftVTableContext().getMethodVFTableLocation(MD);
CGM.getMicrosoftVTableContext().getMethodVFTableLocation(LookupGD);

// The vbases might be ordered differently in the final overrider object
// and the complete object, so the "this" argument may sometimes point to
// memory that has no particular type (e.g. past the complete object).
Expand Down
Expand Up @@ -153,7 +153,7 @@ D::~D() { }
// CHECKFUCHSIA-LABEL: define{{.*}} %class.D* @_ZN1DD1Ev(%class.D* {{[^,]*}} returned{{[^,]*}} %this)

// CHECKMS-LABEL: define dso_local x86_thiscallcc noundef %class.D* @"??0D@@QAE@XZ"(%class.D* {{[^,]*}} returned{{[^,]*}} %this, i32 noundef %is_most_derived)
// CHECKMS-LABEL: define dso_local x86_thiscallcc void @"??1D@@UAE@XZ"(%class.D* {{[^,]*}} %this)
// CHECKMS-LABEL: define dso_local x86_thiscallcc void @"??1D@@UAE@XZ"(i8*{{[^,]*}} %this.coerce)

class E {
public:
Expand Down
7 changes: 3 additions & 4 deletions clang/test/CodeGenCXX/cxx2a-destroying-delete.cpp
Expand Up @@ -90,14 +90,13 @@ void delete_D(D *d) { delete d; }
// For MS, we don't add a new vtable slot to the primary vtable for the virtual
// destructor. Instead we cast to the VDel base class.
// CHECK-MSABI: bitcast {{.*}} %[[d]]
// CHECK-MSABI64-NEXT: getelementptr {{.*}}, i64 8
// CHECK-MSABI32-NEXT: getelementptr {{.*}}, i32 4
// CHECK-MSABI-NEXT: %[[d:.*]] = bitcast i8*
// CHECK-MSABI64-NEXT: %[[d:.*]] = getelementptr {{.*}}, i64 8
// CHECK-MSABI32-NEXT: %[[d:.*]] = getelementptr {{.*}}, i32 4
//
// CHECK: %[[VTABLE:.*]] = load
// CHECK: %[[DTOR:.*]] = load
//
// CHECK: call {{void|noundef i8\*|x86_thiscallcc noundef i8\*}} %[[DTOR]](%{{.*}}* {{[^,]*}} %[[d]]
// CHECK: call {{void|noundef i8\*|x86_thiscallcc noundef i8\*}} %[[DTOR]]({{.*}}*{{[^,]*}} %[[d]]
// CHECK-MSABI-SAME: , i32 noundef 1)
// CHECK-NOT: call
// CHECK: }
Expand Down
13 changes: 4 additions & 9 deletions clang/test/CodeGenCXX/microsoft-abi-structors.cpp
Expand Up @@ -155,28 +155,24 @@ struct C : A, B {
};

C::~C() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1C@dtor_in_second_nvbase@@UAE@XZ"
// CHECK: (%"struct.dtor_in_second_nvbase::C"* {{[^,]*}} %this)
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1C@dtor_in_second_nvbase@@UAE@XZ"(i8*{{[^,]*}} %this.coerce)
// No this adjustment!
// CHECK-NOT: getelementptr
// CHECK: load %"struct.dtor_in_second_nvbase::C"*, %"struct.dtor_in_second_nvbase::C"** %{{.*}}
// Now we this-adjust before calling ~B.
// CHECK: bitcast %"struct.dtor_in_second_nvbase::C"* %{{.*}} to i8*
// CHECK: getelementptr inbounds i8, i8* %{{.*}}, i32 4
// CHECK: bitcast i8* %{{.*}} to %"struct.dtor_in_second_nvbase::B"*
// CHECK: call x86_thiscallcc void @"??1B@dtor_in_second_nvbase@@UAE@XZ"
// CHECK: (%"struct.dtor_in_second_nvbase::B"* {{[^,]*}} %{{.*}})
// CHECK: call x86_thiscallcc void @"??1B@dtor_in_second_nvbase@@UAE@XZ"(%"struct.dtor_in_second_nvbase::B"*{{[^,]*}} %{{.*}})
// CHECK: ret void
}

void foo() {
C c;
}
// DTORS2-LABEL: define linkonce_odr dso_local x86_thiscallcc i8* @"??_EC@dtor_in_second_nvbase@@W3AEPAXI@Z"
// DTORS2: (%"struct.dtor_in_second_nvbase::C"* %this, i32 %should_call_delete)
// DTORS2-LABEL: define linkonce_odr dso_local x86_thiscallcc i8* @"??_EC@dtor_in_second_nvbase@@W3AEPAXI@Z"(i8* %this.coerce, i32 %should_call_delete)
// Do an adjustment from B* to C*.
// DTORS2: getelementptr i8, i8* %{{.*}}, i32 -4
// DTORS2: bitcast i8* %{{.*}} to %"struct.dtor_in_second_nvbase::C"*
// DTORS2: %[[CALL:.*]] = tail call x86_thiscallcc i8* @"??_GC@dtor_in_second_nvbase@@UAEPAXI@Z"
// DTORS2: ret i8* %[[CALL]]
}
Expand All @@ -195,7 +191,7 @@ struct E : virtual C { int e; };
struct F : D, E { ~F(); int f; };

F::~F() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1F@test2@@UAE@XZ"(%"struct.test2::F"*{{[^,]*}})
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1F@test2@@UAE@XZ"(i8*{{[^,]*}})
// Do an adjustment from C vbase subobject to F as though F was the
// complete type.
// CHECK: getelementptr inbounds i8, i8* %{{.*}}, i32 -20
Expand All @@ -209,7 +205,6 @@ void foo() {
// DTORS3-LABEL: define linkonce_odr dso_local x86_thiscallcc void @"??_DF@test2@@QAEXXZ"({{.*}} {{.*}} comdat
// Do an adjustment from C* to F*.
// DTORS3: getelementptr i8, i8* %{{.*}}, i32 20
// DTORS3: bitcast i8* %{{.*}} to %"struct.test2::F"*
// DTORS3: call x86_thiscallcc void @"??1F@test2@@UAE@XZ"
// DTORS3: ret void

Expand Down
87 changes: 56 additions & 31 deletions clang/test/CodeGenCXX/microsoft-abi-virtual-inheritance.cpp
Expand Up @@ -53,6 +53,7 @@ B::B() {
B::~B() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1B@@UAE@XZ"
// Store initial this:
// CHECK: %[[THIS:.*]] = alloca %struct.B*
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.B*
// CHECK: store %struct.B* %{{.*}}, %struct.B** %[[THIS_ADDR]], align 4
// Reload and adjust the this parameter:
Expand Down Expand Up @@ -90,15 +91,15 @@ B::~B() {
// CHECK2: %[[THIS:.*]] = load %struct.B*, %struct.B** {{.*}}
// CHECK2: %[[THIS_i8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
// CHECK2: %[[B_i8:.*]] = getelementptr i8, i8* %[[THIS_i8]], i32 8
// CHECK2: %[[B:.*]] = bitcast i8* %[[B_i8]] to %struct.B*
// CHECK2: call x86_thiscallcc void @"??1B@@UAE@XZ"(%struct.B* {{[^,]*}} %[[B]])
// CHECK2: call x86_thiscallcc void @"??1B@@UAE@XZ"(i8*{{[^,]*}} %[[B_i8]])
// CHECK2: %[[THIS_i8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
// CHECK2: %[[VBASE_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 8
// CHECK2: %[[VBASE:.*]] = bitcast i8* %[[VBASE_i8]] to %struct.VBase*
// CHECK2: call x86_thiscallcc void @"??1VBase@@UAE@XZ"(%struct.VBase* {{[^,]*}} %[[VBASE]])
// CHECK2: ret

// CHECK2-LABEL: define linkonce_odr dso_local x86_thiscallcc noundef i8* @"??_GB@@UAEPAXI@Z"
// CHECK2: store %struct.B* %{{.*}}, %struct.B** %[[THIS:.*]], align 4
// CHECK2: store %struct.B* %{{.*}}, %struct.B** %[[THIS_ADDR:.*]], align 4
// CHECK2: %[[THIS:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
// CHECK2: %[[THIS_PARAM_i8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
Expand Down Expand Up @@ -195,8 +196,7 @@ void delete_B(B *obj) {
// CHECK: %[[VBENTRY:.*]] = getelementptr inbounds i32, i32* %[[VBTABLE]], i32 1
// CHECK: %[[VBOFFSET32:.*]] = load i32, i32* %[[VBENTRY]]
// CHECK: %[[VBOFFSET:.*]] = add nsw i32 0, %[[VBOFFSET32]]
// CHECK: %[[VBASE_i8:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 %[[VBOFFSET]]
// CHECK: %[[VBASE:.*]] = bitcast i8* %[[VBASE_i8]] to %struct.B*
// CHECK: %[[VBASE:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 %[[VBOFFSET]]
//
// CHECK: %[[OBJ_i8:.*]] = bitcast %struct.B* %[[OBJ]] to i8*
// CHECK: %[[VBPTR:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 0
Expand All @@ -206,12 +206,12 @@ void delete_B(B *obj) {
// CHECK: %[[VBOFFSET32:.*]] = load i32, i32* %[[VBENTRY]]
// CHECK: %[[VBOFFSET:.*]] = add nsw i32 0, %[[VBOFFSET32]]
// CHECK: %[[VBASE_i8:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 %[[VBOFFSET]]
// CHECK: %[[VFPTR:.*]] = bitcast i8* %[[VBASE_i8]] to i8* (%struct.B*, i32)***
// CHECK: %[[VFTABLE:.*]] = load i8* (%struct.B*, i32)**, i8* (%struct.B*, i32)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds i8* (%struct.B*, i32)*, i8* (%struct.B*, i32)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load i8* (%struct.B*, i32)*, i8* (%struct.B*, i32)** %[[VFUN]]
// CHECK: %[[VFPTR:.*]] = bitcast i8* %[[VBASE_i8]] to i8* (i8*, i32)***
// CHECK: %[[VFTABLE:.*]] = load i8* (i8*, i32)**, i8* (i8*, i32)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds i8* (i8*, i32)*, i8* (i8*, i32)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load i8* (i8*, i32)*, i8* (i8*, i32)** %[[VFUN]]
//
// CHECK: call x86_thiscallcc noundef i8* %[[VFUN_VALUE]](%struct.B* {{[^,]*}} %[[VBASE]], i32 noundef 1)
// CHECK: call x86_thiscallcc noundef i8* %[[VFUN_VALUE]](i8* {{[^,]*}} %[[VBASE]], i32 noundef 1)
// CHECK: ret void
}

Expand Down Expand Up @@ -295,8 +295,9 @@ struct D : virtual Z, B, C {
} d;

D::~D() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1D@diamond@@UAE@XZ"(%"struct.diamond::D"*{{.*}})
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1D@diamond@@UAE@XZ"(i8*{{.*}})
// Store initial this:
// CHECK: %[[THIS:.*]] = alloca %"struct.diamond::D"*
// CHECK: %[[THIS_ADDR:.*]] = alloca %"struct.diamond::D"*
// CHECK: store %"struct.diamond::D"* %{{.*}}, %"struct.diamond::D"** %[[THIS_ADDR]], align 4
//
Expand All @@ -310,16 +311,13 @@ D::~D() {
// CHECK: %[[C_i8:.*]] = getelementptr inbounds i8, i8* %[[D_i8]], i32 4
// CHECK: %[[C:.*]] = bitcast i8* %[[C_i8]] to %"struct.diamond::C"*
// CHECK: %[[C_i8:.*]] = bitcast %"struct.diamond::C"* %[[C]] to i8*
// CHECK: %[[ARG_i8:.*]] = getelementptr i8, i8* %{{.*}}, i32 16
// FIXME: We might consider changing the dtor this parameter type to i8*.
// CHECK: %[[ARG:.*]] = bitcast i8* %[[ARG_i8]] to %"struct.diamond::C"*
// CHECK: call x86_thiscallcc void @"??1C@diamond@@UAE@XZ"(%"struct.diamond::C"* {{[^,]*}} %[[ARG]])
// CHECK: %[[ARG:.*]] = getelementptr i8, i8* %{{.*}}, i32 16
// CHECK: call x86_thiscallcc void @"??1C@diamond@@UAE@XZ"(i8*{{[^,]*}} %[[ARG]])

// CHECK: %[[B:.*]] = bitcast %"struct.diamond::D"* %[[THIS]] to %"struct.diamond::B"*
// CHECK: %[[B_i8:.*]] = bitcast %"struct.diamond::B"* %[[B]] to i8*
// CHECK: %[[ARG_i8:.*]] = getelementptr i8, i8* %[[B_i8]], i32 4
// CHECK: %[[ARG:.*]] = bitcast i8* %[[ARG_i8]] to %"struct.diamond::B"*
// CHECK: call x86_thiscallcc void @"??1B@diamond@@UAE@XZ"(%"struct.diamond::B"* {{[^,]*}} %[[ARG]])
// CHECK: %[[ARG:.*]] = getelementptr i8, i8* %[[B_i8]], i32 4
// CHECK: call x86_thiscallcc void @"??1B@diamond@@UAE@XZ"(i8*{{[^,]*}} %[[ARG]])
// CHECK: ret void
}

Expand Down Expand Up @@ -443,9 +441,10 @@ struct E : D, B, virtual A {
};

E::~E() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1E@test4@@UAE@XZ"(%"struct.test4::E"* {{[^,]*}} %this)
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1E@test4@@UAE@XZ"(i8*{{[^,]*}} %this.coerce)

// In this case "this" points to the most derived class, so no GEPs needed.
// CHECK: bitcast i8* %this.coerce
// CHECK-NOT: getelementptr
// CHECK-NOT: bitcast
// CHECK: %[[VFPTR_i8:.*]] = bitcast %"struct.test4::E"* %{{.*}} to i32 (...)***
Expand All @@ -458,16 +457,14 @@ void destroy(E *obj) {

// CHECK-NOT: getelementptr
// CHECK: %[[OBJ_i8:.*]] = bitcast %"struct.test4::E"* %[[OBJ]] to i8*
// CHECK: %[[B_i8:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 4
// FIXME: in fact, the call should take i8* and the bitcast is redundant.
// CHECK: %[[B_as_E:.*]] = bitcast i8* %[[B_i8]] to %"struct.test4::E"*
// CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 4
// CHECK: %[[OBJ_i8:.*]] = bitcast %"struct.test4::E"* %[[OBJ:.*]] to i8*
// CHECK: %[[B_i8:.*]] = getelementptr inbounds i8, i8* %[[OBJ_i8]], i32 4
// CHECK: %[[VPTR:.*]] = bitcast i8* %[[B_i8]] to i8* (%"struct.test4::E"*, i32)***
// CHECK: %[[VFTABLE:.*]] = load i8* (%"struct.test4::E"*, i32)**, i8* (%"struct.test4::E"*, i32)*** %[[VPTR]]
// CHECK: %[[VFTENTRY:.*]] = getelementptr inbounds i8* (%"struct.test4::E"*, i32)*, i8* (%"struct.test4::E"*, i32)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN:.*]] = load i8* (%"struct.test4::E"*, i32)*, i8* (%"struct.test4::E"*, i32)** %[[VFTENTRY]]
// CHECK: call x86_thiscallcc noundef i8* %[[VFUN]](%"struct.test4::E"* {{[^,]*}} %[[B_as_E]], i32 noundef 1)
// CHECK: %[[VPTR:.*]] = bitcast i8* %[[B_i8]] to i8* (i8*, i32)***
// CHECK: %[[VFTABLE:.*]] = load i8* (i8*, i32)**, i8* (i8*, i32)*** %[[VPTR]]
// CHECK: %[[VFTENTRY:.*]] = getelementptr inbounds i8* (i8*, i32)*, i8* (i8*, i32)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN:.*]] = load i8* (i8*, i32)*, i8* (i8*, i32)** %[[VFTENTRY]]
// CHECK: call x86_thiscallcc noundef i8* %[[VFUN]](i8*{{[^,]*}} %[[THIS_i8]], i32 noundef 1)
delete obj;
}

Expand Down Expand Up @@ -549,9 +546,37 @@ struct B {
struct C : virtual B {};
struct D : virtual A, C {};
D d;
// CHECK-LABEL: define linkonce_odr dso_local x86_thiscallcc noundef i8* @"??_GD@pr36921@@UAEPAXI@Z"(
// CHECK: %[[THIS:.*]] = load %"struct.pr36921::D"*, %"struct.pr36921::D"**
// CHECK: %[[THIS_UNADJ_i8:.*]] = bitcast %"struct.pr36921::D"* %[[THIS_RELOAD]] to i8*
// CHECK: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_UNADJ_i8]], i32 -4
// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %"struct.pr36921::D"*
// CHECK2-LABEL: define linkonce_odr dso_local x86_thiscallcc noundef i8* @"??_GD@pr36921@@UAEPAXI@Z"(
// CHECK2: %[[THIS:.*]] = load %"struct.pr36921::D"*, %"struct.pr36921::D"**
// CHECK2: %[[THIS_RELOAD:.*]] = load %"struct.pr36921::D"*, %"struct.pr36921::D"**
// CHECK2: %[[THIS_UNADJ_i8:.*]] = bitcast %"struct.pr36921::D"* %[[THIS_RELOAD]] to i8*
// CHECK2: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_UNADJ_i8]], i32 -4
// CHECK2: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %"struct.pr36921::D"*
}

namespace issue_60465 {
// We used to assume the first argument to all destructors was the derived type
// even when there was a 'this' adjustment.
struct A {
virtual ~A();
};

struct alignas(2 * sizeof(void *)) B : virtual A {
~B();
void *x, *y;
};

B::~B() {
// The 'this' parameter should not have a type of %"struct.issue_60465::B"* and
// must not have 'align 8', since at least B's copy of A is only 'align 4'.
// CHECK-LABEL: define dso_local x86_thiscallcc void @"??1B@issue_60465@@UAE@XZ"(i8* noundef %this.coerce)
// CHECK: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %{{.*}}, i32 -12
// CHECK: %[[THIS_ADJ:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %"struct.issue_60465::B"*
// CHECK: %[[X:.*]] = getelementptr inbounds %"struct.issue_60465::B", %"struct.issue_60465::B"* %[[THIS_ADJ]], i32 0, i32 1
// CHECK: store i8* null, i8** %[[X]], align 4
// CHECK: %[[Y:.*]] = getelementptr inbounds %"struct.issue_60465::B", %"struct.issue_60465::B"* %[[THIS_ADJ]], i32 0, i32 2
// CHECK: store i8* null, i8** %[[Y]], align 8
x = nullptr;
y = nullptr;
}
}

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