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[PAC] Fix address discrimination for type info vtable pointers #102199

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Merged
merged 8 commits into from
Oct 18, 2024
Merged

[PAC] Fix address discrimination for type info vtable pointers #102199

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0c20bcd
[PAC] Fix address discrimination for type info vtable pointers
kovdan01 Aug 6, 2024
e0beb3f
Merge branch 'main' into pauth-type-info-addr-discr-fix
kovdan01 Sep 16, 2024
130ff55
Use real addr instead of placeholder for signed type info vt ptrs
kovdan01 Sep 16, 2024
969a877
Merge branch 'main' into pauth-type-info-addr-discr-fix
kovdan01 Sep 29, 2024
55fc2c8
Address review comments
kovdan01 Sep 30, 2024
90d6355
Merge branch 'main' into pauth-type-info-addr-discr-fix
kovdan01 Oct 17, 2024
b08172f
Construct GV before BuildVTablePointer call
kovdan01 Oct 17, 2024
c9d26dd
Fix tests
kovdan01 Oct 17, 2024
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37 changes: 21 additions & 16 deletions clang/lib/CodeGen/ItaniumCXXABI.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -3437,7 +3437,7 @@ class ItaniumRTTIBuilder {
llvm::Constant *GetAddrOfExternalRTTIDescriptor(QualType Ty);

/// BuildVTablePointer - Build the vtable pointer for the given type.
void BuildVTablePointer(const Type *Ty);
void BuildVTablePointer(const Type *Ty, llvm::Constant *StorageAddress);

/// BuildSIClassTypeInfo - Build an abi::__si_class_type_info, used for single
/// inheritance, according to the Itanium C++ ABI, 2.9.5p6b.
Expand Down Expand Up @@ -3834,7 +3834,8 @@ static bool CanUseSingleInheritance(const CXXRecordDecl *RD) {
return true;
}

void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty) {
void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty,
llvm::Constant *StorageAddress) {
// abi::__class_type_info.
static const char * const ClassTypeInfo =
"_ZTVN10__cxxabiv117__class_type_infoE";
Expand Down Expand Up @@ -3981,9 +3982,12 @@ void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty) {
VTable, Two);
}

if (auto &Schema = CGM.getCodeGenOpts().PointerAuth.CXXTypeInfoVTablePointer)
VTable = CGM.getConstantSignedPointer(VTable, Schema, nullptr, GlobalDecl(),
QualType(Ty, 0));
if (const auto &Schema =
CGM.getCodeGenOpts().PointerAuth.CXXTypeInfoVTablePointer)
VTable = CGM.getConstantSignedPointer(
VTable, Schema,
Schema.isAddressDiscriminated() ? StorageAddress : nullptr,
GlobalDecl(), QualType(Ty, 0));

Fields.push_back(VTable);
}
Expand Down Expand Up @@ -4099,8 +4103,18 @@ llvm::Constant *ItaniumRTTIBuilder::BuildTypeInfo(
llvm::GlobalVariable::LinkageTypes Linkage,
llvm::GlobalValue::VisibilityTypes Visibility,
llvm::GlobalValue::DLLStorageClassTypes DLLStorageClass) {
SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
llvm::Module &M = CGM.getModule();
llvm::GlobalVariable *OldGV = M.getNamedGlobal(Name);
// int8 is an arbitrary type to be replaced later with replaceInitializer.
llvm::GlobalVariable *GV =
new llvm::GlobalVariable(M, CGM.Int8Ty, /*isConstant=*/true, Linkage,
/*Initializer=*/nullptr, Name);

// Add the vtable pointer.
BuildVTablePointer(cast<Type>(Ty));
BuildVTablePointer(cast<Type>(Ty), GV);

// And the name.
llvm::GlobalVariable *TypeName = GetAddrOfTypeName(Ty, Linkage);
Expand Down Expand Up @@ -4218,16 +4232,7 @@ llvm::Constant *ItaniumRTTIBuilder::BuildTypeInfo(
llvm_unreachable("HLSL doesn't support RTTI");
}

llvm::Constant *Init = llvm::ConstantStruct::getAnon(Fields);

SmallString<256> Name;
llvm::raw_svector_ostream Out(Name);
CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty, Out);
llvm::Module &M = CGM.getModule();
llvm::GlobalVariable *OldGV = M.getNamedGlobal(Name);
llvm::GlobalVariable *GV =
new llvm::GlobalVariable(M, Init->getType(),
/*isConstant=*/true, Linkage, Init, Name);
GV->replaceInitializer(llvm::ConstantStruct::getAnon(Fields));

// Export the typeinfo in the same circumstances as the vtable is exported.
auto GVDLLStorageClass = DLLStorageClass;
Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGenCXX/RelativeVTablesABI/child-inheritted-from-parent-in-comdat.cpp
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Expand Up @@ -4,8 +4,8 @@
// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s

// The inline function is emitted in each module with the same comdat
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1A = comdat any
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1B.rtti_proxy = comdat any

// The VTable is emitted everywhere used
Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGenCXX/RelativeVTablesABI/inlined-key-function.cpp
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Expand Up @@ -4,8 +4,8 @@
// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -o - -emit-llvm | FileCheck %s

// CHECK: $_ZTV1A = comdat any
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1A = comdat any
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1A.rtti_proxy = comdat any

// The VTable is linkonce_odr and in a comdat here bc it’s key function is inline defined.
Expand Down
4 changes: 2 additions & 2 deletions clang/test/CodeGenCXX/RelativeVTablesABI/parent-and-child-in-comdats.cpp
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Expand Up @@ -8,12 +8,12 @@
// CHECK: $_ZN1A3fooEv = comdat any
// CHECK: $_ZN1B3fooEv = comdat any
// CHECK: $_ZTV1A = comdat any
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1A = comdat any
// CHECK: $_ZTS1A = comdat any
// CHECK: $_ZTI1A.rtti_proxy = comdat any
// CHECK: $_ZTV1B = comdat any
// CHECK: $_ZTS1B = comdat any
// CHECK: $_ZTI1B = comdat any
// CHECK: $_ZTS1B = comdat any
// CHECK: $_ZTI1B.rtti_proxy = comdat any

// Both the vtables for A and B are emitted and in their own comdats.
Expand Down
4 changes: 2 additions & 2 deletions clang/test/CodeGenCXX/RelativeVTablesABI/parent-vtable-in-comdat.cpp
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Expand Up @@ -7,17 +7,17 @@
// A::foo() has a comdat since it is an inline function
// CHECK: $_ZN1A3fooEv = comdat any
// CHECK: $_ZTV1A = comdat any
// CHECK: $_ZTI1A = comdat any
// CHECK: $_ZTS1A = comdat any

// The VTable for A has its own comdat section bc it has no key function
// CHECK: $_ZTI1A = comdat any
// CHECK: $_ZTI1A.rtti_proxy = comdat any

// The VTable for A is emitted here and in a comdat section since it has no key function, and is used in this module when creating an instance of A.
// CHECK: @_ZTV1A.local = linkonce_odr hidden unnamed_addr constant { [3 x i32] } { [3 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint (ptr @_ZTI1A.rtti_proxy to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @_ZN1A3fooEv to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, comdat($_ZTV1A), align 4
// CHECK: @_ZTI1A = linkonce_odr constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, comdat, align 8
// CHECK: @_ZTVN10__cxxabiv117__class_type_infoE = external global [0 x ptr]
// CHECK: @_ZTS1A = linkonce_odr constant [3 x i8] c"1A\00", comdat, align 1
// CHECK: @_ZTI1A = linkonce_odr constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, comdat, align 8
// CHECK: @_ZTI1A.rtti_proxy = linkonce_odr hidden unnamed_addr constant ptr @_ZTI1A, comdat
// CHECK: @_ZTV1A = linkonce_odr unnamed_addr alias { [3 x i32] }, ptr @_ZTV1A.local

Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGenCXX/RelativeVTablesABI/simple-vtable-definition.cpp
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Expand Up @@ -9,9 +9,9 @@
// The vtable definition itself is private so we can take relative references to
// it. The vtable symbol will be exposed through a public alias.
// CHECK: @_ZTV1A.local = internal unnamed_addr constant { [3 x i32] } { [3 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint (ptr @_ZTI1A.rtti_proxy to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @_ZN1A3fooEv to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, align 4
// CHECK: @_ZTI1A ={{.*}} constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, align 8
// CHECK: @_ZTVN10__cxxabiv117__class_type_infoE = external global [0 x ptr]
// CHECK: @_ZTS1A ={{.*}} constant [3 x i8] c"1A\00", align 1
// CHECK: @_ZTI1A ={{.*}} constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, align 8

// The rtti should be in a comdat
// CHECK: @_ZTI1A.rtti_proxy = {{.*}}comdat
Expand Down
4 changes: 2 additions & 2 deletions clang/test/CodeGenCXX/RelativeVTablesABI/type-info.cpp
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Expand Up @@ -5,12 +5,12 @@
// CHECK: $_ZTI1A.rtti_proxy = comdat any
// CHECK: $_ZTI1B.rtti_proxy = comdat any

// CHECK: @_ZTI1A ={{.*}} constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, align 8
// CHECK: @_ZTVN10__cxxabiv117__class_type_infoE = external global [0 x ptr]
// CHECK: @_ZTS1A ={{.*}} constant [3 x i8] c"1A\00", align 1
// CHECK: @_ZTI1A ={{.*}} constant { ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i32 8), ptr @_ZTS1A }, align 8
// CHECK: @_ZTI1B ={{.*}} constant { ptr, ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv120__si_class_type_infoE, i32 8), ptr @_ZTS1B, ptr @_ZTI1A }, align 8
// CHECK: @_ZTVN10__cxxabiv120__si_class_type_infoE = external global [0 x ptr]
// CHECK: @_ZTS1B ={{.*}} constant [3 x i8] c"1B\00", align 1
// CHECK: @_ZTI1B ={{.*}} constant { ptr, ptr, ptr } { ptr getelementptr inbounds (i8, ptr @_ZTVN10__cxxabiv120__si_class_type_infoE, i32 8), ptr @_ZTS1B, ptr @_ZTI1A }, align 8
// CHECK: @_ZTI1A.rtti_proxy = linkonce_odr hidden unnamed_addr constant ptr @_ZTI1A, comdat
// CHECK: @_ZTI1B.rtti_proxy = linkonce_odr hidden unnamed_addr constant ptr @_ZTI1B, comdat

Expand Down
6 changes: 3 additions & 3 deletions clang/test/CodeGenCXX/armv7k.cpp
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Expand Up @@ -50,17 +50,17 @@ namespace test2 {

struct __attribute__((visibility("hidden"))) B {};
const std::type_info &b0 = typeid(B);
// CHECK-GLOBALS: @_ZTSN5test21BE = linkonce_odr hidden constant
// CHECK-GLOBALS: @_ZTIN5test21BE = linkonce_odr hidden constant { {{.*}}, ptr @_ZTSN5test21BE }
// CHECK-GLOBALS: @_ZTSN5test21BE = linkonce_odr hidden constant

const std::type_info &b1 = typeid(B*);
// CHECK-GLOBALS: @_ZTSPN5test21BE = linkonce_odr hidden constant
// CHECK-GLOBALS: @_ZTIPN5test21BE = linkonce_odr hidden constant { {{.*}}, ptr @_ZTSPN5test21BE, i32 0, ptr @_ZTIN5test21BE
// CHECK-GLOBALS: @_ZTSPN5test21BE = linkonce_odr hidden constant

struct C {};
const std::type_info &c0 = typeid(C);
// CHECK-GLOBALS: @_ZTSN5test21CE = linkonce_odr constant [11 x i8] c"N5test21CE\00"
// CHECK-GLOBALS: @_ZTIN5test21CE = linkonce_odr constant { {{.*}}, ptr @_ZTSN5test21CE }
// CHECK-GLOBALS: @_ZTSN5test21CE = linkonce_odr constant [11 x i8] c"N5test21CE\00"
}

// va_list should be based on "char *" rather than "ptr".
Expand Down
4 changes: 2 additions & 2 deletions clang/test/CodeGenCXX/dynamic-cast-address-space.cpp
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Expand Up @@ -10,17 +10,17 @@ B fail;
// CHECK: @_ZTV1B = linkonce_odr unnamed_addr addrspace(1) constant { [3 x ptr addrspace(1)] } { [3 x ptr addrspace(1)] [ptr addrspace(1) null, ptr addrspace(1) @_ZTI1B, ptr addrspace(1) addrspacecast (ptr @_ZN1A1fEv to ptr addrspace(1))] }, comdat, align 8
// CHECK: @fail = addrspace(1) global { ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds inrange(-16, 8) ({ [3 x ptr addrspace(1)] }, ptr addrspace(1) @_ZTV1B, i32 0, i32 0, i32 2) }, align 8
// CHECK: @_ZTI1A = external addrspace(1) constant ptr addrspace(1)
// CHECK: @_ZTI1B = linkonce_odr addrspace(1) constant { ptr addrspace(1), ptr addrspace(1), ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds (ptr addrspace(1), ptr addrspace(1) @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr addrspace(1) @_ZTS1B, ptr addrspace(1) @_ZTI1A }, comdat, align 8
// CHECK: @_ZTVN10__cxxabiv120__si_class_type_infoE = external addrspace(1) global [0 x ptr addrspace(1)]
// CHECK: @_ZTS1B = linkonce_odr addrspace(1) constant [3 x i8] c"1B\00", comdat, align 1
// CHECK: @_ZTI1B = linkonce_odr addrspace(1) constant { ptr addrspace(1), ptr addrspace(1), ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds (ptr addrspace(1), ptr addrspace(1) @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr addrspace(1) @_ZTS1B, ptr addrspace(1) @_ZTI1A }, comdat, align 8
// CHECK: @__oclc_ABI_version = weak_odr hidden local_unnamed_addr addrspace(4) constant i32 500
//.
// WITH-NONZERO-DEFAULT-AS: @_ZTV1B = linkonce_odr unnamed_addr addrspace(1) constant { [3 x ptr addrspace(1)] } { [3 x ptr addrspace(1)] [ptr addrspace(1) null, ptr addrspace(1) @_ZTI1B, ptr addrspace(1) addrspacecast (ptr addrspace(4) @_ZN1A1fEv to ptr addrspace(1))] }, comdat, align 8
// WITH-NONZERO-DEFAULT-AS: @fail = addrspace(1) global { ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds inrange(-16, 8) ({ [3 x ptr addrspace(1)] }, ptr addrspace(1) @_ZTV1B, i32 0, i32 0, i32 2) }, align 8
// WITH-NONZERO-DEFAULT-AS: @_ZTI1A = external addrspace(1) constant ptr addrspace(1)
// WITH-NONZERO-DEFAULT-AS: @_ZTI1B = linkonce_odr addrspace(1) constant { ptr addrspace(1), ptr addrspace(1), ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds (ptr addrspace(1), ptr addrspace(1) @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr addrspace(1) @_ZTS1B, ptr addrspace(1) @_ZTI1A }, comdat, align 8
// WITH-NONZERO-DEFAULT-AS: @_ZTVN10__cxxabiv120__si_class_type_infoE = external addrspace(1) global [0 x ptr addrspace(1)]
// WITH-NONZERO-DEFAULT-AS: @_ZTS1B = linkonce_odr addrspace(1) constant [3 x i8] c"1B\00", comdat, align 1
// WITH-NONZERO-DEFAULT-AS: @_ZTI1B = linkonce_odr addrspace(1) constant { ptr addrspace(1), ptr addrspace(1), ptr addrspace(1) } { ptr addrspace(1) getelementptr inbounds (ptr addrspace(1), ptr addrspace(1) @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr addrspace(1) @_ZTS1B, ptr addrspace(1) @_ZTI1A }, comdat, align 8
//.
// CHECK-LABEL: define dso_local noundef nonnull align 8 dereferenceable(8) ptr @_Z1fP1A(
// CHECK-SAME: ptr noundef [[A:%.*]]) #[[ATTR0:[0-9]+]] personality ptr @__gxx_personality_v0 {
Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGenCXX/exceptions-no-rtti.cpp
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Expand Up @@ -3,8 +3,8 @@
// CHECK: @_ZTIN5test11AE = linkonce_odr constant
// CHECK: @_ZTIN5test11BE = linkonce_odr constant
// CHECK: @_ZTIN5test11CE = linkonce_odr constant
// CHECK: @_ZTIN5test11DE = linkonce_odr constant
// CHECK: @_ZTIPN5test11DE = linkonce_odr constant {{.*}} @_ZTIN5test11DE
// CHECK: @_ZTIN5test11DE = linkonce_odr constant

// PR6974: this shouldn't crash
namespace test0 {
Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGenCXX/implicit-record-visibility.cpp
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Expand Up @@ -7,6 +7,6 @@
// under -fvisibility=hidden the type of function f, due to its va_list (aka
// __builtin_va_list, aka __va_list_tag (*)[1]) parameter would be hidden:

// CHECK: @_ZTSFvP13__va_list_tagE = linkonce_odr constant
// CHECK: @_ZTIFvP13__va_list_tagE = linkonce_odr constant
// CHECK: @_ZTSFvP13__va_list_tagE = linkonce_odr constant
void f(va_list) { (void)typeid(f); }
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