CODEGENOPT(WholeProgramVTables, 1, 0) ///< Whether to apply whole-program
/// vtable optimization.
-CODEGENOPT(VirtualFunctionElimination, 1, 0) ///< Whether to apply the dead
- /// virtual function elimination
- /// optimization.
-
/// Whether to use public LTO visibility for entities in std and stdext
/// namespaces. This is enabled by clang-cl's /MT and /MTd flags.
CODEGENOPT(LTOVisibilityPublicStd, 1, 0)
HelpText<"Emits more virtual tables to improve devirtualization">;
def fno_force_emit_vtables : Flag<["-"], "fno-force-emit-vtables">, Group<f_Group>,
Flags<[CoreOption]>;
-
-def fvirtual_function_elimination : Flag<["-"], "fvirtual-function-elimination">, Group<f_Group>,
- Flags<[CoreOption, CC1Option]>,
- HelpText<"Enables dead virtual function elimination optimization. Requires -flto=full">;
-def fno_virtual_function_elimination : Flag<["-"], "fno-virtual-function_elimination">, Group<f_Group>,
- Flags<[CoreOption]>;
-
def fwrapv : Flag<["-"], "fwrapv">, Group<f_Group>, Flags<[CC1Option]>,
HelpText<"Treat signed integer overflow as two's complement">;
def fwritable_strings : Flag<["-"], "fwritable-strings">, Group<f_Group>, Flags<[CC1Option]>,
bool CodeGenFunction::ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD) {
if (!CGM.getCodeGenOpts().WholeProgramVTables ||
+ !SanOpts.has(SanitizerKind::CFIVCall) ||
+ !CGM.getCodeGenOpts().SanitizeTrap.has(SanitizerKind::CFIVCall) ||
!CGM.HasHiddenLTOVisibility(RD))
return false;
- if (CGM.getCodeGenOpts().VirtualFunctionElimination)
- return true;
-
- if (!SanOpts.has(SanitizerKind::CFIVCall) ||
- !CGM.getCodeGenOpts().SanitizeTrap.has(SanitizerKind::CFIVCall))
- return false;
-
std::string TypeName = RD->getQualifiedNameAsString();
return !getContext().getSanitizerBlacklist().isBlacklistedType(
SanitizerKind::CFIVCall, TypeName);
TypeId});
llvm::Value *CheckResult = Builder.CreateExtractValue(CheckedLoad, 1);
- std::string TypeName = RD->getQualifiedNameAsString();
- if (SanOpts.has(SanitizerKind::CFIVCall) &&
- !getContext().getSanitizerBlacklist().isBlacklistedType(
- SanitizerKind::CFIVCall, TypeName)) {
- EmitCheck(std::make_pair(CheckResult, SanitizerKind::CFIVCall),
- SanitizerHandler::CFICheckFail, {}, {});
- }
+ EmitCheck(std::make_pair(CheckResult, SanitizerKind::CFIVCall),
+ SanitizerHandler::CFICheckFail, nullptr, nullptr);
return Builder.CreateBitCast(
Builder.CreateExtractValue(CheckedLoad, 0),
assert(!VTable->isDeclaration() && "Shouldn't set properties on declaration");
CGM.setGVProperties(VTable, RD);
- CGM.EmitVTableTypeMetadata(RD, VTable, *VTLayout.get());
+ CGM.EmitVTableTypeMetadata(VTable, *VTLayout.get());
return VTable;
}
return true;
}
-llvm::GlobalObject::VCallVisibility
-CodeGenModule::GetVCallVisibilityLevel(const CXXRecordDecl *RD) {
- LinkageInfo LV = RD->getLinkageAndVisibility();
- llvm::GlobalObject::VCallVisibility TypeVis;
- if (!isExternallyVisible(LV.getLinkage()))
- TypeVis = llvm::GlobalObject::VCallVisibilityTranslationUnit;
- else if (HasHiddenLTOVisibility(RD))
- TypeVis = llvm::GlobalObject::VCallVisibilityLinkageUnit;
- else
- TypeVis = llvm::GlobalObject::VCallVisibilityPublic;
-
- for (auto B : RD->bases())
- if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
- GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
-
- for (auto B : RD->vbases())
- if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
- GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
-
- return TypeVis;
-}
-
-void CodeGenModule::EmitVTableTypeMetadata(const CXXRecordDecl *RD,
- llvm::GlobalVariable *VTable,
+void CodeGenModule::EmitVTableTypeMetadata(llvm::GlobalVariable *VTable,
const VTableLayout &VTLayout) {
if (!getCodeGenOpts().LTOUnit)
return;
VTable->addTypeMetadata((PointerWidth * I).getQuantity(), MD);
}
}
-
- if (getCodeGenOpts().VirtualFunctionElimination) {
- llvm::GlobalObject::VCallVisibility TypeVis = GetVCallVisibilityLevel(RD);
- if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
- VTable->addVCallVisibilityMetadata(TypeVis);
- }
}
/// optimization.
bool HasHiddenLTOVisibility(const CXXRecordDecl *RD);
- /// Returns the vcall visibility of the given type. This is the scope in which
- /// a virtual function call could be made which ends up being dispatched to a
- /// member function of this class. This scope can be wider than the visibility
- /// of the class itself when the class has a more-visible dynamic base class.
- llvm::GlobalObject::VCallVisibility
- GetVCallVisibilityLevel(const CXXRecordDecl *RD);
-
/// Emit type metadata for the given vtable using the given layout.
- void EmitVTableTypeMetadata(const CXXRecordDecl *RD,
- llvm::GlobalVariable *VTable,
+ void EmitVTableTypeMetadata(llvm::GlobalVariable *VTable,
const VTableLayout &VTLayout);
/// Generate a cross-DSO type identifier for MD.
VTableOffset = Builder.CreateTrunc(VTableOffset, CGF.Int32Ty);
VTableOffset = Builder.CreateZExt(VTableOffset, CGM.PtrDiffTy);
}
+ // Compute the address of the virtual function pointer.
+ llvm::Value *VFPAddr = Builder.CreateGEP(VTable, VTableOffset);
// Check the address of the function pointer if CFI on member function
// pointers is enabled.
llvm::Constant *CheckTypeDesc;
bool ShouldEmitCFICheck = CGF.SanOpts.has(SanitizerKind::CFIMFCall) &&
CGM.HasHiddenLTOVisibility(RD);
- bool ShouldEmitVFEInfo = CGM.getCodeGenOpts().VirtualFunctionElimination &&
- CGM.HasHiddenLTOVisibility(RD);
- llvm::Value *VirtualFn = nullptr;
-
- {
+ if (ShouldEmitCFICheck) {
CodeGenFunction::SanitizerScope SanScope(&CGF);
- llvm::Value *TypeId = nullptr;
- llvm::Value *CheckResult = nullptr;
-
- if (ShouldEmitCFICheck || ShouldEmitVFEInfo) {
- // If doing CFI or VFE, we will need the metadata node to check against.
- llvm::Metadata *MD =
- CGM.CreateMetadataIdentifierForVirtualMemPtrType(QualType(MPT, 0));
- TypeId = llvm::MetadataAsValue::get(CGF.getLLVMContext(), MD);
- }
- llvm::Value *VFPAddr = Builder.CreateGEP(VTable, VTableOffset);
-
- if (ShouldEmitVFEInfo) {
- // If doing VFE, load from the vtable with a type.checked.load intrinsic
- // call. Note that we use the GEP to calculate the address to load from
- // and pass 0 as the offset to the intrinsic. This is because every
- // vtable slot of the correct type is marked with matching metadata, and
- // we know that the load must be from one of these slots.
- llvm::Value *CheckedLoad = Builder.CreateCall(
- CGM.getIntrinsic(llvm::Intrinsic::type_checked_load),
- {VFPAddr, llvm::ConstantInt::get(CGM.Int32Ty, 0), TypeId});
- CheckResult = Builder.CreateExtractValue(CheckedLoad, 1);
- VirtualFn = Builder.CreateExtractValue(CheckedLoad, 0);
- VirtualFn = Builder.CreateBitCast(VirtualFn, FTy->getPointerTo(),
- "memptr.virtualfn");
- } else {
- // When not doing VFE, emit a normal load, as it allows more
- // optimisations than type.checked.load.
- if (ShouldEmitCFICheck) {
- CheckResult = Builder.CreateCall(
- CGM.getIntrinsic(llvm::Intrinsic::type_test),
- {Builder.CreateBitCast(VFPAddr, CGF.Int8PtrTy), TypeId});
- }
- VFPAddr =
- Builder.CreateBitCast(VFPAddr, FTy->getPointerTo()->getPointerTo());
- VirtualFn = Builder.CreateAlignedLoad(VFPAddr, CGF.getPointerAlign(),
- "memptr.virtualfn");
- }
- assert(VirtualFn && "Virtual fuction pointer not created!");
- assert((!ShouldEmitCFICheck || !ShouldEmitVFEInfo || CheckResult) &&
- "Check result required but not created!");
-
- if (ShouldEmitCFICheck) {
- // If doing CFI, emit the check.
- CheckSourceLocation = CGF.EmitCheckSourceLocation(E->getBeginLoc());
- CheckTypeDesc = CGF.EmitCheckTypeDescriptor(QualType(MPT, 0));
- llvm::Constant *StaticData[] = {
- llvm::ConstantInt::get(CGF.Int8Ty, CodeGenFunction::CFITCK_VMFCall),
- CheckSourceLocation,
- CheckTypeDesc,
- };
+ CheckSourceLocation = CGF.EmitCheckSourceLocation(E->getBeginLoc());
+ CheckTypeDesc = CGF.EmitCheckTypeDescriptor(QualType(MPT, 0));
+ llvm::Constant *StaticData[] = {
+ llvm::ConstantInt::get(CGF.Int8Ty, CodeGenFunction::CFITCK_VMFCall),
+ CheckSourceLocation,
+ CheckTypeDesc,
+ };
- if (CGM.getCodeGenOpts().SanitizeTrap.has(SanitizerKind::CFIMFCall)) {
- CGF.EmitTrapCheck(CheckResult);
- } else {
- llvm::Value *AllVtables = llvm::MetadataAsValue::get(
- CGM.getLLVMContext(),
- llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
- llvm::Value *ValidVtable = Builder.CreateCall(
- CGM.getIntrinsic(llvm::Intrinsic::type_test), {VTable, AllVtables});
- CGF.EmitCheck(std::make_pair(CheckResult, SanitizerKind::CFIMFCall),
- SanitizerHandler::CFICheckFail, StaticData,
- {VTable, ValidVtable});
- }
+ llvm::Metadata *MD =
+ CGM.CreateMetadataIdentifierForVirtualMemPtrType(QualType(MPT, 0));
+ llvm::Value *TypeId = llvm::MetadataAsValue::get(CGF.getLLVMContext(), MD);
+
+ llvm::Value *TypeTest = Builder.CreateCall(
+ CGM.getIntrinsic(llvm::Intrinsic::type_test), {VFPAddr, TypeId});
- FnVirtual = Builder.GetInsertBlock();
+ if (CGM.getCodeGenOpts().SanitizeTrap.has(SanitizerKind::CFIMFCall)) {
+ CGF.EmitTrapCheck(TypeTest);
+ } else {
+ llvm::Value *AllVtables = llvm::MetadataAsValue::get(
+ CGM.getLLVMContext(),
+ llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
+ llvm::Value *ValidVtable = Builder.CreateCall(
+ CGM.getIntrinsic(llvm::Intrinsic::type_test), {VTable, AllVtables});
+ CGF.EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIMFCall),
+ SanitizerHandler::CFICheckFail, StaticData,
+ {VTable, ValidVtable});
}
- } // End of sanitizer scope
+ FnVirtual = Builder.GetInsertBlock();
+ }
+
+ // Load the virtual function to call.
+ VFPAddr = Builder.CreateBitCast(VFPAddr, FTy->getPointerTo()->getPointerTo());
+ llvm::Value *VirtualFn = Builder.CreateAlignedLoad(
+ VFPAddr, CGF.getPointerAlign(), "memptr.virtualfn");
CGF.EmitBranch(FnEnd);
// In the non-virtual path, the function pointer is actually a
EmitFundamentalRTTIDescriptors(RD);
if (!VTable->isDeclarationForLinker())
- CGM.EmitVTableTypeMetadata(RD, VTable, VTLayout);
+ CGM.EmitVTableTypeMetadata(VTable, VTLayout);
}
bool ItaniumCXXABI::isVirtualOffsetNeededForVTableField(
CmdArgs.push_back(Args.MakeArgString(TargetInfo.str()));
}
- bool VirtualFunctionElimination =
- Args.hasFlag(options::OPT_fvirtual_function_elimination,
- options::OPT_fno_virtual_function_elimination, false);
- if (VirtualFunctionElimination) {
- // VFE requires full LTO (currently, this might be relaxed to allow ThinLTO
- // in the future).
- if (D.getLTOMode() != LTOK_Full)
- D.Diag(diag::err_drv_argument_only_allowed_with)
- << "-fvirtual-function-elimination"
- << "-flto=full";
-
- CmdArgs.push_back("-fvirtual-function-elimination");
- }
-
- // VFE requires whole-program-vtables, and enables it by default.
- bool WholeProgramVTables = Args.hasFlag(
- options::OPT_fwhole_program_vtables,
- options::OPT_fno_whole_program_vtables, VirtualFunctionElimination);
- if (VirtualFunctionElimination && !WholeProgramVTables) {
- D.Diag(diag::err_drv_argument_not_allowed_with)
- << "-fno-whole-program-vtables"
- << "-fvirtual-function-elimination";
- }
-
+ bool WholeProgramVTables =
+ Args.hasFlag(options::OPT_fwhole_program_vtables,
+ options::OPT_fno_whole_program_vtables, false);
if (WholeProgramVTables) {
if (!D.isUsingLTO())
D.Diag(diag::err_drv_argument_only_allowed_with)
Opts.CodeViewGHash = Args.hasArg(OPT_gcodeview_ghash);
Opts.MacroDebugInfo = Args.hasArg(OPT_debug_info_macro);
Opts.WholeProgramVTables = Args.hasArg(OPT_fwhole_program_vtables);
- Opts.VirtualFunctionElimination =
- Args.hasArg(OPT_fvirtual_function_elimination);
Opts.LTOVisibilityPublicStd = Args.hasArg(OPT_flto_visibility_public_std);
Opts.SplitDwarfFile = Args.getLastArgValue(OPT_split_dwarf_file);
Opts.SplitDwarfOutput = Args.getLastArgValue(OPT_split_dwarf_output);
+++ /dev/null
-// RUN: %clang_cc1 -flto -flto-unit -triple x86_64-unknown-linux -emit-llvm -fvirtual-function-elimination -fwhole-program-vtables -o - %s | FileCheck %s
-
-
-// Anonymous namespace.
-namespace {
-// CHECK: @_ZTVN12_GLOBAL__N_11AE = {{.*}} !vcall_visibility [[VIS_TU:![0-9]+]]
-struct A {
- A() {}
- virtual int f() { return 1; }
-};
-}
-void *construct_A() {
- return new A();
-}
-
-
-// Hidden visibility.
-// CHECK: @_ZTV1B = {{.*}} !vcall_visibility [[VIS_DSO:![0-9]+]]
-struct __attribute__((visibility("hidden"))) B {
- B() {}
- virtual int f() { return 1; }
-};
-B *construct_B() {
- return new B();
-}
-
-
-// Default visibility.
-// CHECK-NOT: @_ZTV1C = {{.*}} !vcall_visibility
-struct __attribute__((visibility("default"))) C {
- C() {}
- virtual int f() { return 1; }
-};
-C *construct_C() {
- return new C();
-}
-
-
-// Hidden visibility, public LTO visibility.
-// CHECK-NOT: @_ZTV1D = {{.*}} !vcall_visibility
-struct __attribute__((visibility("hidden"))) [[clang::lto_visibility_public]] D {
- D() {}
- virtual int f() { return 1; }
-};
-D *construct_D() {
- return new D();
-}
-
-
-// Hidden visibility, but inherits from class with default visibility.
-// CHECK-NOT: @_ZTV1E = {{.*}} !vcall_visibility
-struct __attribute__((visibility("hidden"))) E : C {
- E() {}
- virtual int f() { return 1; }
-};
-E *construct_E() {
- return new E();
-}
-
-
-// Anonymous namespace, but inherits from class with default visibility.
-// CHECK-NOT: @_ZTVN12_GLOBAL__N_11FE = {{.*}} !vcall_visibility
-namespace {
-struct __attribute__((visibility("hidden"))) F : C {
- F() {}
- virtual int f() { return 1; }
-};
-}
-void *construct_F() {
- return new F();
-}
-
-
-// Anonymous namespace, but inherits from class with hidden visibility.
-// CHECK: @_ZTVN12_GLOBAL__N_11GE = {{.*}} !vcall_visibility [[VIS_DSO:![0-9]+]]
-namespace {
-struct __attribute__((visibility("hidden"))) G : B {
- G() {}
- virtual int f() { return 1; }
-};
-}
-void *construct_G() {
- return new G();
-}
-
-
-// CHECK-DAG: [[VIS_DSO]] = !{i64 1}
-// CHECK-DAG: [[VIS_TU]] = !{i64 2}
+++ /dev/null
-// RUN: %clang_cc1 -triple x86_64-unknown-linux -flto -flto-unit -fvirtual-function-elimination -fwhole-program-vtables -emit-llvm -o - %s | FileCheck %s
-
-
-struct __attribute__((visibility("default"))) A {
- virtual void foo();
-};
-
-void test_1(A *p) {
- // A has default visibility, so no need for type.checked.load.
-// CHECK-LABEL: define void @_Z6test_1P1A
-// CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** {{%.+}}, i64 0
-// CHECK: [[FN_PTR:%.+]] = load void (%struct.A*)*, void (%struct.A*)** [[FN_PTR_ADDR]]
-// CHECK: call void [[FN_PTR]](
- p->foo();
-}
-
-
-struct __attribute__((visibility("hidden"))) [[clang::lto_visibility_public]] B {
- virtual void foo();
-};
-
-void test_2(B *p) {
- // B has public LTO visibility, so no need for type.checked.load.
-// CHECK-LABEL: define void @_Z6test_2P1B
-// CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.B*)*, void (%struct.B*)** {{%.+}}, i64 0
-// CHECK: [[FN_PTR:%.+]] = load void (%struct.B*)*, void (%struct.B*)** [[FN_PTR_ADDR]]
-// CHECK: call void [[FN_PTR]](
- p->foo();
-}
-
-
-struct __attribute__((visibility("hidden"))) C {
- virtual void foo();
- virtual void bar();
-};
-
-void test_3(C *p) {
- // C has hidden visibility, so we generate type.checked.load to allow VFE.
-// CHECK-LABEL: define void @_Z6test_3P1C
-// CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 0, metadata !"_ZTS1C")
-// CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
-// CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
-// CHECK: call void [[FN_PTR]](
- p->foo();
-}
-
-void test_4(C *p) {
- // When using type.checked.load, we pass the vtable offset to the intrinsic,
- // rather than adding it to the pointer with a GEP.
-// CHECK-LABEL: define void @_Z6test_4P1C
-// CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 8, metadata !"_ZTS1C")
-// CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
-// CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
-// CHECK: call void [[FN_PTR]](
- p->bar();
-}
-
-void test_5(C *p, void (C::*q)(void)) {
- // We also use type.checked.load for the virtual side of member function
- // pointer calls. We use a GEP to calculate the address to load from and pass
- // 0 as the offset to the intrinsic, because we know that the load must be
- // from exactly the point marked by one of the function-type metadatas (in
- // this case "_ZTSM1CFvvE.virtual"). If we passed the offset from the member
- // function pointer to the intrinsic, this information would be lost. No
- // codegen changes on the non-virtual side.
-// CHECK-LABEL: define void @_Z6test_5P1CMS_FvvE(
-// CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr i8, i8* %vtable, i64 {{%.+}}
-// CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* [[FN_PTR_ADDR]], i32 0, metadata !"_ZTSM1CFvvE.virtual")
-// CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
-// CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
-
-// CHECK: [[PHI:%.+]] = phi void (%struct.C*)* {{.*}}[ [[FN_PTR]], {{.*}} ]
-// CHECK: call void [[PHI]](
- (p->*q)();
-}
+++ /dev/null
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -### %s 2>&1 | FileCheck --check-prefix=BAD-LTO %s
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -flto=thin -### %s 2>&1 | FileCheck --check-prefix=BAD-LTO %s
-// BAD-LTO: invalid argument '-fvirtual-function-elimination' only allowed with '-flto=full'
-
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -flto -### %s 2>&1 | FileCheck --check-prefix=GOOD %s
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -flto=full -### %s 2>&1 | FileCheck --check-prefix=GOOD %s
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -flto -fwhole-program-vtables -### %s 2>&1 | FileCheck --check-prefix=GOOD %s
-// GOOD: "-fvirtual-function-elimination" "-fwhole-program-vtables"
-
-// RUN: %clang -target x86_64-unknown-linux -fvirtual-function-elimination -fno-whole-program-vtables -flto -### %s 2>&1 | FileCheck --check-prefix=NO-WHOLE-PROGRAM-VTABLES %s
-// NO-WHOLE-PROGRAM-VTABLES: invalid argument '-fno-whole-program-vtables' not allowed with '-fvirtual-function-elimination'
!0 = !{i32 1, !"short_wchar", i32 1}
!1 = !{i32 1, !"short_enum", i32 0}
-LTO Post-Link Module Flags Metadata
------------------------------------
-
-Some optimisations are only when the entire LTO unit is present in the current
-module. This is represented by the ``LTOPostLink`` module flags metadata, which
-will be created with a value of ``1`` when LTO linking occurs.
-
Automatic Linker Flags Named Metadata
=====================================
The ``llvm.type.test`` intrinsic tests whether the given pointer is associated
with the given type identifier.
-.. _type.checked.load:
-
'``llvm.type.checked.load``' Intrinsic
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
}
.. _GlobalLayoutBuilder: https://github.com/llvm/llvm-project/blob/master/llvm/include/llvm/Transforms/IPO/LowerTypeTests.h
-
-``!vcall_visibility`` Metadata
-==============================
-
-In order to allow removing unused function pointers from vtables, we need to
-know whether every virtual call which could use it is known to the compiler, or
-whether another translation unit could introduce more calls through the vtable.
-This is not the same as the linkage of the vtable, because call sites could be
-using a pointer of a more widely-visible base class. For example, consider this
-code:
-
-.. code-block:: c++
-
- __attribute__((visibility("default")))
- struct A {
- virtual void f();
- };
-
- __attribute__((visibility("hidden")))
- struct B : A {
- virtual void f();
- };
-
-With LTO, we know that all code which can see the declaration of ``B`` is
-visible to us. However, a pointer to a ``B`` could be cast to ``A*`` and passed
-to another linkage unit, which could then call ``f`` on it. This call would
-load from the vtable for ``B`` (using the object pointer), and then call
-``B::f``. This means we can't remove the function pointer from ``B``'s vtable,
-or the implementation of ``B::f``. However, if we can see all code which knows
-about any dynamic base class (which would be the case if ``B`` only inherited
-from classes with hidden visibility), then this optimisation would be valid.
-
-This concept is represented in IR by the ``!vcall_visibility`` metadata
-attached to vtable objects, with the following values:
-
-.. list-table::
- :header-rows: 1
- :widths: 10 90
-
- * - Value
- - Behavior
-
- * - 0 (or omitted)
- - **Public**
- Virtual function calls using this vtable could be made from external
- code.
-
- * - 1
- - **Linkage Unit**
- All virtual function calls which might use this vtable are in the
- current LTO unit, meaning they will be in the current module once
- LTO linking has been performed.
-
- * - 2
- - **Translation Unit**
- All virtual function calls which might use this vtable are in the
- current module.
-
-In addition, all function pointer loads from a vtable marked with the
-``!vcall_visibility`` metadata (with a non-zero value) must be done using the
-:ref:`llvm.type.checked.load <type.checked.load>` intrinsic, so that virtual
-calls sites can be correlated with the vtables which they might load from.
-Other parts of the vtable (RTTI, offset-to-top, ...) can still be accessed with
-normal loads.
SmallVectorImpl<Instruction *> &LoadedPtrs,
SmallVectorImpl<Instruction *> &Preds, bool &HasNonCallUses,
const CallInst *CI, DominatorTree &DT);
-
-Constant *getPointerAtOffset(Constant *I, uint64_t Offset, Module &M);
}
#endif
LLVM_FIXED_MD_KIND(MD_callback, "callback", 26)
LLVM_FIXED_MD_KIND(MD_preserve_access_index, "llvm.preserve.access.index", 27)
LLVM_FIXED_MD_KIND(MD_misexpect, "misexpect", 28)
-LLVM_FIXED_MD_KIND(MD_vcall_visibility, "vcall_visibility", 29)
class Metadata;
class GlobalObject : public GlobalValue {
-public:
- // VCallVisibility - values for visibility metadata attached to vtables. This
- // describes the scope in which a virtual call could end up being dispatched
- // through this vtable.
- enum VCallVisibility {
- // Type is potentially visible to external code.
- VCallVisibilityPublic = 0,
- // Type is only visible to code which will be in the current Module after
- // LTO internalization.
- VCallVisibilityLinkageUnit = 1,
- // Type is only visible to code in the current Module.
- VCallVisibilityTranslationUnit = 2,
- };
-
protected:
GlobalObject(Type *Ty, ValueTy VTy, Use *Ops, unsigned NumOps,
LinkageTypes Linkage, const Twine &Name,
void copyMetadata(const GlobalObject *Src, unsigned Offset);
void addTypeMetadata(unsigned Offset, Metadata *TypeID);
- void addVCallVisibilityMetadata(VCallVisibility Visibility);
- VCallVisibility getVCallVisibility() const;
protected:
void copyAttributesFrom(const GlobalObject *Src);
/// Comdat -> Globals in that Comdat section.
std::unordered_multimap<Comdat *, GlobalValue *> ComdatMembers;
- /// !type metadata -> set of (vtable, offset) pairs
- DenseMap<Metadata *, SmallSet<std::pair<GlobalVariable *, uint64_t>, 4>>
- TypeIdMap;
-
- // Global variables which are vtables, and which we have enough information
- // about to safely do dead virtual function elimination.
- SmallPtrSet<GlobalValue *, 32> VFESafeVTables;
-
void UpdateGVDependencies(GlobalValue &GV);
void MarkLive(GlobalValue &GV,
SmallVectorImpl<GlobalValue *> *Updates = nullptr);
bool RemoveUnusedGlobalValue(GlobalValue &GV);
- // Dead virtual function elimination.
- void AddVirtualFunctionDependencies(Module &M);
- void ScanVTables(Module &M);
- void ScanTypeCheckedLoadIntrinsics(Module &M);
- void ScanVTableLoad(Function *Caller, Metadata *TypeId, uint64_t CallOffset);
-
void ComputeDependencies(Value *V, SmallPtrSetImpl<GlobalValue *> &U);
};
findCallsAtConstantOffset(DevirtCalls, &HasNonCallUses, LoadedPtr,
Offset->getZExtValue(), CI, DT);
}
-
-Constant *llvm::getPointerAtOffset(Constant *I, uint64_t Offset, Module &M) {
- if (I->getType()->isPointerTy()) {
- if (Offset == 0)
- return I;
- return nullptr;
- }
-
- const DataLayout &DL = M.getDataLayout();
-
- if (auto *C = dyn_cast<ConstantStruct>(I)) {
- const StructLayout *SL = DL.getStructLayout(C->getType());
- if (Offset >= SL->getSizeInBytes())
- return nullptr;
-
- unsigned Op = SL->getElementContainingOffset(Offset);
- return getPointerAtOffset(cast<Constant>(I->getOperand(Op)),
- Offset - SL->getElementOffset(Op), M);
- }
- if (auto *C = dyn_cast<ConstantArray>(I)) {
- ArrayType *VTableTy = C->getType();
- uint64_t ElemSize = DL.getTypeAllocSize(VTableTy->getElementType());
-
- unsigned Op = Offset / ElemSize;
- if (Op >= C->getNumOperands())
- return nullptr;
-
- return getPointerAtOffset(cast<Constant>(I->getOperand(Op)),
- Offset % ElemSize, M);
- }
- return nullptr;
-}
TypeID}));
}
-void GlobalObject::addVCallVisibilityMetadata(VCallVisibility Visibility) {
- addMetadata(LLVMContext::MD_vcall_visibility,
- *MDNode::get(getContext(),
- {ConstantAsMetadata::get(ConstantInt::get(
- Type::getInt64Ty(getContext()), Visibility))}));
-}
-
-GlobalObject::VCallVisibility GlobalObject::getVCallVisibility() const {
- if (MDNode *MD = getMetadata(LLVMContext::MD_vcall_visibility)) {
- uint64_t Val = cast<ConstantInt>(
- cast<ConstantAsMetadata>(MD->getOperand(0))->getValue())
- ->getZExtValue();
- assert(Val <= 2 && "unknown vcall visibility!");
- return (VCallVisibility)Val;
- }
- return VCallVisibility::VCallVisibilityPublic;
-}
-
void Function::setSubprogram(DISubprogram *SP) {
setMetadata(LLVMContext::MD_dbg, SP);
}
GV->setLinkage(GlobalValue::InternalLinkage);
}
- RegularLTO.CombinedModule->addModuleFlag(Module::Error, "LTOPostLink", 1);
-
if (Conf.PostInternalizeModuleHook &&
!Conf.PostInternalizeModuleHook(0, *RegularLTO.CombinedModule))
return Error::success();
internalizeModule(*MergedModule, mustPreserveGV);
- MergedModule->addModuleFlag(Module::Error, "LTOPostLink", 1);
-
ScopeRestrictionsDone = true;
}
#include "llvm/Transforms/IPO/GlobalDCE.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/TypeMetadataUtils.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
-#include "llvm/IR/Operator.h"
#include "llvm/Pass.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Utils/CtorUtils.h"
#define DEBUG_TYPE "globaldce"
-static cl::opt<bool>
- ClEnableVFE("enable-vfe", cl::Hidden, cl::init(true), cl::ZeroOrMore,
- cl::desc("Enable virtual function elimination"));
-
STATISTIC(NumAliases , "Number of global aliases removed");
STATISTIC(NumFunctions, "Number of functions removed");
STATISTIC(NumIFuncs, "Number of indirect functions removed");
STATISTIC(NumVariables, "Number of global variables removed");
-STATISTIC(NumVFuncs, "Number of virtual functions removed");
namespace {
class GlobalDCELegacyPass : public ModulePass {
ComputeDependencies(User, Deps);
Deps.erase(&GV); // Remove self-reference.
for (GlobalValue *GVU : Deps) {
- // If this is a dep from a vtable to a virtual function, and we have
- // complete information about all virtual call sites which could call
- // though this vtable, then skip it, because the call site information will
- // be more precise.
- if (VFESafeVTables.count(GVU) && isa<Function>(&GV)) {
- LLVM_DEBUG(dbgs() << "Ignoring dep " << GVU->getName() << " -> "
- << GV.getName() << "\n");
- continue;
- }
GVDependencies[GVU].insert(&GV);
}
}
if (Updates)
Updates->push_back(&GV);
if (Comdat *C = GV.getComdat()) {
- for (auto &&CM : make_range(ComdatMembers.equal_range(C))) {
+ for (auto &&CM : make_range(ComdatMembers.equal_range(C)))
MarkLive(*CM.second, Updates); // Recursion depth is only two because only
// globals in the same comdat are visited.
- }
- }
-}
-
-void GlobalDCEPass::ScanVTables(Module &M) {
- SmallVector<MDNode *, 2> Types;
- LLVM_DEBUG(dbgs() << "Building type info -> vtable map\n");
-
- auto *LTOPostLinkMD =
- cast_or_null<ConstantAsMetadata>(M.getModuleFlag("LTOPostLink"));
- bool LTOPostLink =
- LTOPostLinkMD &&
- (cast<ConstantInt>(LTOPostLinkMD->getValue())->getZExtValue() != 0);
-
- for (GlobalVariable &GV : M.globals()) {
- Types.clear();
- GV.getMetadata(LLVMContext::MD_type, Types);
- if (GV.isDeclaration() || Types.empty())
- continue;
-
- // Use the typeid metadata on the vtable to build a mapping from typeids to
- // the list of (GV, offset) pairs which are the possible vtables for that
- // typeid.
- for (MDNode *Type : Types) {
- Metadata *TypeID = Type->getOperand(1).get();
-
- uint64_t Offset =
- cast<ConstantInt>(
- cast<ConstantAsMetadata>(Type->getOperand(0))->getValue())
- ->getZExtValue();
-
- TypeIdMap[TypeID].insert(std::make_pair(&GV, Offset));
- }
-
- // If the type corresponding to the vtable is private to this translation
- // unit, we know that we can see all virtual functions which might use it,
- // so VFE is safe.
- if (auto GO = dyn_cast<GlobalObject>(&GV)) {
- GlobalObject::VCallVisibility TypeVis = GO->getVCallVisibility();
- if (TypeVis == GlobalObject::VCallVisibilityTranslationUnit ||
- (LTOPostLink &&
- TypeVis == GlobalObject::VCallVisibilityLinkageUnit)) {
- LLVM_DEBUG(dbgs() << GV.getName() << " is safe for VFE\n");
- VFESafeVTables.insert(&GV);
- }
- }
- }
-}
-
-void GlobalDCEPass::ScanVTableLoad(Function *Caller, Metadata *TypeId,
- uint64_t CallOffset) {
- for (auto &VTableInfo : TypeIdMap[TypeId]) {
- GlobalVariable *VTable = VTableInfo.first;
- uint64_t VTableOffset = VTableInfo.second;
-
- Constant *Ptr =
- getPointerAtOffset(VTable->getInitializer(), VTableOffset + CallOffset,
- *Caller->getParent());
- if (!Ptr) {
- LLVM_DEBUG(dbgs() << "can't find pointer in vtable!\n");
- VFESafeVTables.erase(VTable);
- return;
- }
-
- auto Callee = dyn_cast<Function>(Ptr->stripPointerCasts());
- if (!Callee) {
- LLVM_DEBUG(dbgs() << "vtable entry is not function pointer!\n");
- VFESafeVTables.erase(VTable);
- return;
- }
-
- LLVM_DEBUG(dbgs() << "vfunc dep " << Caller->getName() << " -> "
- << Callee->getName() << "\n");
- GVDependencies[Caller].insert(Callee);
}
}
-void GlobalDCEPass::ScanTypeCheckedLoadIntrinsics(Module &M) {
- LLVM_DEBUG(dbgs() << "Scanning type.checked.load intrinsics\n");
- Function *TypeCheckedLoadFunc =
- M.getFunction(Intrinsic::getName(Intrinsic::type_checked_load));
-
- if (!TypeCheckedLoadFunc)
- return;
-
- for (auto U : TypeCheckedLoadFunc->users()) {
- auto CI = dyn_cast<CallInst>(U);
- if (!CI)
- continue;
-
- auto *Offset = dyn_cast<ConstantInt>(CI->getArgOperand(1));
- Value *TypeIdValue = CI->getArgOperand(2);
- auto *TypeId = cast<MetadataAsValue>(TypeIdValue)->getMetadata();
-
- if (Offset) {
- ScanVTableLoad(CI->getFunction(), TypeId, Offset->getZExtValue());
- } else {
- // type.checked.load with a non-constant offset, so assume every entry in
- // every matching vtable is used.
- for (auto &VTableInfo : TypeIdMap[TypeId]) {
- VFESafeVTables.erase(VTableInfo.first);
- }
- }
- }
-}
-
-void GlobalDCEPass::AddVirtualFunctionDependencies(Module &M) {
- if (!ClEnableVFE)
- return;
-
- ScanVTables(M);
-
- if (VFESafeVTables.empty())
- return;
-
- ScanTypeCheckedLoadIntrinsics(M);
-
- LLVM_DEBUG(
- dbgs() << "VFE safe vtables:\n";
- for (auto *VTable : VFESafeVTables)
- dbgs() << " " << VTable->getName() << "\n";
- );
-}
-
PreservedAnalyses GlobalDCEPass::run(Module &M, ModuleAnalysisManager &MAM) {
bool Changed = false;
if (Comdat *C = GA.getComdat())
ComdatMembers.insert(std::make_pair(C, &GA));
- // Add dependencies between virtual call sites and the virtual functions they
- // might call, if we have that information.
- AddVirtualFunctionDependencies(M);
-
// Loop over the module, adding globals which are obviously necessary.
for (GlobalObject &GO : M.global_objects()) {
Changed |= RemoveUnusedGlobalValue(GO);
};
NumFunctions += DeadFunctions.size();
- for (Function *F : DeadFunctions) {
- if (!F->use_empty()) {
- // Virtual functions might still be referenced by one or more vtables,
- // but if we've proven them to be unused then it's safe to replace the
- // virtual function pointers with null, allowing us to remove the
- // function itself.
- ++NumVFuncs;
- F->replaceAllUsesWith(ConstantPointerNull::get(F->getType()));
- }
+ for (Function *F : DeadFunctions)
EraseUnusedGlobalValue(F);
- }
NumVariables += DeadGlobalVars.size();
for (GlobalVariable *GV : DeadGlobalVars)
ConstantDependenciesCache.clear();
GVDependencies.clear();
ComdatMembers.clear();
- TypeIdMap.clear();
- VFESafeVTables.clear();
if (Changed)
return PreservedAnalyses::none();
void buildTypeIdentifierMap(
std::vector<VTableBits> &Bits,
DenseMap<Metadata *, std::set<TypeMemberInfo>> &TypeIdMap);
+ Constant *getPointerAtOffset(Constant *I, uint64_t Offset);
bool
tryFindVirtualCallTargets(std::vector<VirtualCallTarget> &TargetsForSlot,
const std::set<TypeMemberInfo> &TypeMemberInfos,
}
}
+Constant *DevirtModule::getPointerAtOffset(Constant *I, uint64_t Offset) {
+ if (I->getType()->isPointerTy()) {
+ if (Offset == 0)
+ return I;
+ return nullptr;
+ }
+
+ const DataLayout &DL = M.getDataLayout();
+
+ if (auto *C = dyn_cast<ConstantStruct>(I)) {
+ const StructLayout *SL = DL.getStructLayout(C->getType());
+ if (Offset >= SL->getSizeInBytes())
+ return nullptr;
+
+ unsigned Op = SL->getElementContainingOffset(Offset);
+ return getPointerAtOffset(cast<Constant>(I->getOperand(Op)),
+ Offset - SL->getElementOffset(Op));
+ }
+ if (auto *C = dyn_cast<ConstantArray>(I)) {
+ ArrayType *VTableTy = C->getType();
+ uint64_t ElemSize = DL.getTypeAllocSize(VTableTy->getElementType());
+
+ unsigned Op = Offset / ElemSize;
+ if (Op >= C->getNumOperands())
+ return nullptr;
+
+ return getPointerAtOffset(cast<Constant>(I->getOperand(Op)),
+ Offset % ElemSize);
+ }
+ return nullptr;
+}
+
bool DevirtModule::tryFindVirtualCallTargets(
std::vector<VirtualCallTarget> &TargetsForSlot,
const std::set<TypeMemberInfo> &TypeMemberInfos, uint64_t ByteOffset) {
return false;
Constant *Ptr = getPointerAtOffset(TM.Bits->GV->getInitializer(),
- TM.Offset + ByteOffset, M);
+ TM.Offset + ByteOffset);
if (!Ptr)
return false;
for (VTableBits &B : Bits)
rebuildGlobal(B);
- // We have lowered or deleted the type checked load intrinsics, so we no
- // longer have enough information to reason about the liveness of virtual
- // function pointers in GlobalDCE.
- for (GlobalVariable &GV : M.globals())
- GV.eraseMetadata(LLVMContext::MD_vcall_visibility);
-
return true;
}
+++ /dev/null
-; RUN: opt %s -o %t1.bc
-
-; RUN: llvm-lto %t1.bc -o %t1.save.opt -save-merged-module -O1 --exported-symbol=foo
-; RUN: llvm-dis < %t1.save.opt.merged.bc | FileCheck %s
-
-; RUN: llvm-lto2 run %t1.bc -o %t.out.o -save-temps \
-; RUN: -r=%t1.bc,foo,pxl
-; RUN: llvm-dis < %t.out.o.0.2.internalize.bc | FileCheck %s
-
-target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
-target triple = "armv7a-unknown-linux"
-
-define void @foo() {
-entry:
- ret void
-}
-
-; CHECK: !llvm.module.flags = !{[[MD_NUM:![0-9]+]]}
-; CHECK: [[MD_NUM]] = !{i32 1, !"LTOPostLink", i32 1}
; RUN: llvm-lto -thinlto-action=import %t2.bc -thinlto-index=%t3.bc \
; RUN: -o /dev/null -stats \
; RUN: 2>&1 | FileCheck %s -check-prefix=LAZY
-; LAZY: 65 bitcode-reader - Number of Metadata records loaded
+; LAZY: 63 bitcode-reader - Number of Metadata records loaded
; LAZY: 2 bitcode-reader - Number of MDStrings loaded
; RUN: llvm-lto -thinlto-action=import %t2.bc -thinlto-index=%t3.bc \
; RUN: -o /dev/null -disable-ondemand-mds-loading -stats \
; RUN: 2>&1 | FileCheck %s -check-prefix=NOTLAZY
-; NOTLAZY: 74 bitcode-reader - Number of Metadata records loaded
+; NOTLAZY: 72 bitcode-reader - Number of Metadata records loaded
; NOTLAZY: 7 bitcode-reader - Number of MDStrings loaded
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; struct A {
-; A();
-; virtual int foo();
-; };
-;
-; struct B : A {
-; B();
-; virtual int foo();
-; };
-;
-; A::A() {}
-; B::B() {}
-; int A::foo() { return 42; }
-; int B::foo() { return 1337; }
-;
-; extern "C" int test(A *p) { return p->foo(); }
-
-; The virtual call in test could be dispatched to either A::foo or B::foo, so
-; both must be retained.
-
-%struct.A = type { i32 (...)** }
-%struct.B = type { %struct.A }
-
-; CHECK: @_ZTV1A = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*)] }
-@_ZTV1A = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
-
-; CHECK: @_ZTV1B = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*)* @_ZN1B3fooEv to i8*)] }
-@_ZTV1B = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*)* @_ZN1B3fooEv to i8*)] }, align 8, !type !0, !type !1, !type !3, !type !4, !vcall_visibility !2
-
-; CHECK: define internal i32 @_ZN1A3fooEv(
-define internal i32 @_ZN1A3fooEv(%struct.A* nocapture readnone %this) {
-entry:
- ret i32 42
-}
-
-; CHECK: define internal i32 @_ZN1B3fooEv(
-define internal i32 @_ZN1B3fooEv(%struct.B* nocapture readnone %this) {
-entry:
- ret i32 1337
-}
-
-define hidden void @_ZN1AC2Ev(%struct.A* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden void @_ZN1BC2Ev(%struct.B* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden i32 @test(%struct.A* %p) {
-entry:
- %0 = bitcast %struct.A* %p to i8**
- %vtable1 = load i8*, i8** %0, align 8
- %1 = tail call { i8*, i1 } @llvm.type.checked.load(i8* %vtable1, i32 0, metadata !"_ZTS1A"), !nosanitize !10
- %2 = extractvalue { i8*, i1 } %1, 0, !nosanitize !10
- %3 = bitcast i8* %2 to i32 (%struct.A*)*, !nosanitize !10
- %call = tail call i32 %3(%struct.A* %p)
- ret i32 %call
-}
-
-declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata) #2
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFivE.virtual"}
-!2 = !{i64 2}
-!3 = !{i64 16, !"_ZTS1B"}
-!4 = !{i64 16, !"_ZTSM1BFivE.virtual"}
-!10 = !{}
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; struct A {
-; A();
-; virtual int foo(int);
-; virtual int bar(float);
-; };
-;
-; struct B : A {
-; B();
-; virtual int foo(int);
-; virtual int bar(float);
-; };
-;
-; A::A() {}
-; B::B() {}
-; int A::foo(int) { return 1; }
-; int A::bar(float) { return 2; }
-; int B::foo(int) { return 3; }
-; int B::bar(float) { return 4; }
-;
-; extern "C" int test(A *p, int (A::*q)(int)) { return (p->*q)(42); }
-
-; Member function pointers are tracked by the combination of their object type
-; and function type, which must both be compatible. Here, the call is through a
-; pointer of type "int (A::*q)(int)", so the call could be dispatched to A::foo
-; or B::foo. It can't be dispatched to A::bar or B::bar as the function pointer
-; does not match, so those can be removed.
-
-%struct.A = type { i32 (...)** }
-%struct.B = type { %struct.A }
-
-; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*, i32)* @_ZN1A3fooEi to i8*), i8* null] }
-@_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*, i32)* @_ZN1A3fooEi to i8*), i8* bitcast (i32 (%struct.A*, float)* @_ZN1A3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !3
-; CHECK: @_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* null] }
-@_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* bitcast (i32 (%struct.B*, float)* @_ZN1B3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !type !4, !type !5, !type !6, !vcall_visibility !3
-
-
-; CHECK: define internal i32 @_ZN1A3fooEi(
-define internal i32 @_ZN1A3fooEi(%struct.A* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
-entry:
- ret i32 1
-}
-
-; CHECK-NOT: define internal i32 @_ZN1A3barEf(
-define internal i32 @_ZN1A3barEf(%struct.A* nocapture readnone %this, float) unnamed_addr #1 align 2 {
-entry:
- ret i32 2
-}
-
-; CHECK: define internal i32 @_ZN1B3fooEi(
-define internal i32 @_ZN1B3fooEi(%struct.B* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
-entry:
- ret i32 3
-}
-
-; CHECK-NOT: define internal i32 @_ZN1B3barEf(
-define internal i32 @_ZN1B3barEf(%struct.B* nocapture readnone %this, float) unnamed_addr #1 align 2 {
-entry:
- ret i32 4
-}
-
-
-define hidden void @_ZN1AC2Ev(%struct.A* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden void @_ZN1BC2Ev(%struct.B* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden i32 @test(%struct.A* %p, i64 %q.coerce0, i64 %q.coerce1) {
-entry:
- %0 = bitcast %struct.A* %p to i8*
- %1 = getelementptr inbounds i8, i8* %0, i64 %q.coerce1
- %this.adjusted = bitcast i8* %1 to %struct.A*
- %2 = and i64 %q.coerce0, 1
- %memptr.isvirtual = icmp eq i64 %2, 0
- br i1 %memptr.isvirtual, label %memptr.nonvirtual, label %memptr.virtual
-
-memptr.virtual: ; preds = %entry
- %3 = bitcast i8* %1 to i8**
- %vtable = load i8*, i8** %3, align 8
- %4 = add i64 %q.coerce0, -1
- %5 = getelementptr i8, i8* %vtable, i64 %4, !nosanitize !12
- %6 = tail call { i8*, i1 } @llvm.type.checked.load(i8* %5, i32 0, metadata !"_ZTSM1AFiiE.virtual"), !nosanitize !12
- %7 = extractvalue { i8*, i1 } %6, 0, !nosanitize !12
- %memptr.virtualfn = bitcast i8* %7 to i32 (%struct.A*, i32)*, !nosanitize !12
- br label %memptr.end
-
-memptr.nonvirtual: ; preds = %entry
- %memptr.nonvirtualfn = inttoptr i64 %q.coerce0 to i32 (%struct.A*, i32)*
- br label %memptr.end
-
-memptr.end: ; preds = %memptr.nonvirtual, %memptr.virtual
- %8 = phi i32 (%struct.A*, i32)* [ %memptr.virtualfn, %memptr.virtual ], [ %memptr.nonvirtualfn, %memptr.nonvirtual ]
- %call = tail call i32 %8(%struct.A* %this.adjusted, i32 42)
- ret i32 %call
-}
-
-declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata)
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFiiE.virtual"}
-!2 = !{i64 24, !"_ZTSM1AFifE.virtual"}
-!3 = !{i64 2}
-!4 = !{i64 16, !"_ZTS1B"}
-!5 = !{i64 16, !"_ZTSM1BFiiE.virtual"}
-!6 = !{i64 24, !"_ZTSM1BFifE.virtual"}
-!12 = !{}
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; struct A {
-; A();
-; virtual int foo();
-; };
-;
-; struct B : A {
-; B();
-; virtual int foo();
-; };
-;
-; A::A() {}
-; B::B() {}
-; int A::foo() { return 42; }
-; int B::foo() { return 1337; }
-;
-; extern "C" int test(B *p) { return p->foo(); }
-
-; The virtual call in test can only be dispatched to B::foo (or a more-derived
-; class, if there was one), so A::foo can be removed.
-
-%struct.A = type { i32 (...)** }
-%struct.B = type { %struct.A }
-
-; CHECK: @_ZTV1A = internal unnamed_addr constant { [3 x i8*] } zeroinitializer
-@_ZTV1A = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
-
-; CHECK: @_ZTV1B = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*)* @_ZN1B3fooEv to i8*)] }
-@_ZTV1B = internal unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*)* @_ZN1B3fooEv to i8*)] }, align 8, !type !0, !type !1, !type !3, !type !4, !vcall_visibility !2
-
-; CHECK-NOT: define internal i32 @_ZN1A3fooEv(
-define internal i32 @_ZN1A3fooEv(%struct.A* nocapture readnone %this) {
-entry:
- ret i32 42
-}
-
-; CHECK: define internal i32 @_ZN1B3fooEv(
-define internal i32 @_ZN1B3fooEv(%struct.B* nocapture readnone %this) {
-entry:
- ret i32 1337
-}
-
-define hidden void @_ZN1AC2Ev(%struct.A* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden void @_ZN1BC2Ev(%struct.B* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden i32 @test(%struct.B* %p) {
-entry:
- %0 = bitcast %struct.B* %p to i8**
- %vtable1 = load i8*, i8** %0, align 8
- %1 = tail call { i8*, i1 } @llvm.type.checked.load(i8* %vtable1, i32 0, metadata !"_ZTS1B"), !nosanitize !10
- %2 = extractvalue { i8*, i1 } %1, 0, !nosanitize !10
- %3 = bitcast i8* %2 to i32 (%struct.B*)*, !nosanitize !10
- %call = tail call i32 %3(%struct.B* %p)
- ret i32 %call
-}
-
-declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata) #2
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFivE.virtual"}
-!2 = !{i64 2}
-!3 = !{i64 16, !"_ZTS1B"}
-!4 = !{i64 16, !"_ZTSM1BFivE.virtual"}
-!10 = !{}
+++ /dev/null
-
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; struct A {
-; A();
-; virtual int foo(int);
-; virtual int bar(float);
-; };
-;
-; struct B : A {
-; B();
-; virtual int foo(int);
-; virtual int bar(float);
-; };
-;
-; A::A() {}
-; B::B() {}
-; int A::foo(int) { return 1; }
-; int A::bar(float) { return 2; }
-; int B::foo(int) { return 3; }
-; int B::bar(float) { return 4; }
-;
-; extern "C" int test(B *p, int (B::*q)(int)) { return (p->*q)(42); }
-
-; Member function pointers are tracked by the combination of their object type
-; and function type, which must both be compatible. Here, the call is through a
-; pointer of type "int (B::*q)(int)", so the call could only be dispatched to
-; B::foo. It can't be dispatched to A::bar or B::bar as the function pointer
-; does not match, and it can't be dispatched to A::foo as the object type
-; doesn't match, so those can be removed.
-
-%struct.A = type { i32 (...)** }
-%struct.B = type { %struct.A }
-
-; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x i8*] } zeroinitializer
-@_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*, i32)* @_ZN1A3fooEi to i8*), i8* bitcast (i32 (%struct.A*, float)* @_ZN1A3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !3
-; CHECK: @_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* null] }
-@_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* bitcast (i32 (%struct.B*, float)* @_ZN1B3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !type !4, !type !5, !type !6, !vcall_visibility !3
-
-
-; CHECK-NOT: define internal i32 @_ZN1A3fooEi(
-define internal i32 @_ZN1A3fooEi(%struct.A* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
-entry:
- ret i32 1
-}
-
-; CHECK-NOT: define internal i32 @_ZN1A3barEf(
-define internal i32 @_ZN1A3barEf(%struct.A* nocapture readnone %this, float) unnamed_addr #1 align 2 {
-entry:
- ret i32 2
-}
-
-; CHECK: define internal i32 @_ZN1B3fooEi(
-define internal i32 @_ZN1B3fooEi(%struct.B* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
-entry:
- ret i32 3
-}
-
-; CHECK-NOT: define internal i32 @_ZN1B3barEf(
-define internal i32 @_ZN1B3barEf(%struct.B* nocapture readnone %this, float) unnamed_addr #1 align 2 {
-entry:
- ret i32 4
-}
-
-
-define hidden void @_ZN1AC2Ev(%struct.A* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden void @_ZN1BC2Ev(%struct.B* nocapture %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-define hidden i32 @test(%struct.B* %p, i64 %q.coerce0, i64 %q.coerce1) {
-entry:
- %0 = bitcast %struct.B* %p to i8*
- %1 = getelementptr inbounds i8, i8* %0, i64 %q.coerce1
- %this.adjusted = bitcast i8* %1 to %struct.B*
- %2 = and i64 %q.coerce0, 1
- %memptr.isvirtual = icmp eq i64 %2, 0
- br i1 %memptr.isvirtual, label %memptr.nonvirtual, label %memptr.virtual
-
-memptr.virtual: ; preds = %entry
- %3 = bitcast i8* %1 to i8**
- %vtable = load i8*, i8** %3, align 8
- %4 = add i64 %q.coerce0, -1
- %5 = getelementptr i8, i8* %vtable, i64 %4, !nosanitize !12
- %6 = tail call { i8*, i1 } @llvm.type.checked.load(i8* %5, i32 0, metadata !"_ZTSM1BFiiE.virtual"), !nosanitize !12
- %7 = extractvalue { i8*, i1 } %6, 0, !nosanitize !12
- %memptr.virtualfn = bitcast i8* %7 to i32 (%struct.B*, i32)*, !nosanitize !12
- br label %memptr.end
-
-memptr.nonvirtual: ; preds = %entry
- %memptr.nonvirtualfn = inttoptr i64 %q.coerce0 to i32 (%struct.B*, i32)*
- br label %memptr.end
-
-memptr.end: ; preds = %memptr.nonvirtual, %memptr.virtual
- %8 = phi i32 (%struct.B*, i32)* [ %memptr.virtualfn, %memptr.virtual ], [ %memptr.nonvirtualfn, %memptr.nonvirtual ]
- %call = tail call i32 %8(%struct.B* %this.adjusted, i32 42)
- ret i32 %call
-}
-
-declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata)
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFiiE.virtual"}
-!2 = !{i64 24, !"_ZTSM1AFifE.virtual"}
-!3 = !{i64 2}
-!4 = !{i64 16, !"_ZTS1B"}
-!5 = !{i64 16, !"_ZTSM1BFiiE.virtual"}
-!6 = !{i64 24, !"_ZTSM1BFifE.virtual"}
-!12 = !{}
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-; structs A, B and C have vcall_visibility of public, linkage-unit and
-; translation-unit respectively. This test is run after LTO linking (the
-; LTOPostLink metadata is present), so B and C can be VFE'd.
-
-target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
-
-%struct.A = type { i32 (...)** }
-
-@_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
-
-define internal void @_ZN1AC2Ev(%struct.A* %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK: define {{.*}} @_ZN1A3fooEv(
-define internal void @_ZN1A3fooEv(%struct.A* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Av() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.A*
- tail call void @_ZN1AC2Ev(%struct.A* %0)
- ret i8* %call
-}
-
-
-%struct.B = type { i32 (...)** }
-
-@_ZTV1B = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.B*)* @_ZN1B3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !3
-
-define internal void @_ZN1BC2Ev(%struct.B* %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK-NOT: define {{.*}} @_ZN1B3fooEv(
-define internal void @_ZN1B3fooEv(%struct.B* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Bv() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.B*
- tail call void @_ZN1BC2Ev(%struct.B* %0)
- ret i8* %call
-}
-
-
-%struct.C = type { i32 (...)** }
-
-@_ZTV1C = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.C*)* @_ZN1C3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !4
-
-define internal void @_ZN1CC2Ev(%struct.C* %this) {
-entry:
- %0 = getelementptr inbounds %struct.C, %struct.C* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1C, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK-NOT: define {{.*}} @_ZN1C3fooEv(
-define internal void @_ZN1C3fooEv(%struct.C* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Cv() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.C*
- tail call void @_ZN1CC2Ev(%struct.C* %0)
- ret i8* %call
-}
-
-declare dso_local noalias nonnull i8* @_Znwm(i64)
-
-!llvm.module.flags = !{!5}
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFvvE.virtual"}
-!2 = !{i64 0} ; public vcall visibility
-!3 = !{i64 1} ; linkage-unit vcall visibility
-!4 = !{i64 2} ; translation-unit vcall visibility
-!5 = !{i32 1, !"LTOPostLink", i32 1}
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-; structs A, B and C have vcall_visibility of public, linkage-unit and
-; translation-unit respectively. This test is run before LTO linking occurs
-; (the LTOPostLink metadata is not present), so only C can be VFE'd.
-
-target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
-
-%struct.A = type { i32 (...)** }
-
-@_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
-
-define internal void @_ZN1AC2Ev(%struct.A* %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK: define {{.*}} @_ZN1A3fooEv(
-define internal void @_ZN1A3fooEv(%struct.A* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Av() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.A*
- tail call void @_ZN1AC2Ev(%struct.A* %0)
- ret i8* %call
-}
-
-
-%struct.B = type { i32 (...)** }
-
-@_ZTV1B = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.B*)* @_ZN1B3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !3
-
-define internal void @_ZN1BC2Ev(%struct.B* %this) {
-entry:
- %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK: define {{.*}} @_ZN1B3fooEv(
-define internal void @_ZN1B3fooEv(%struct.B* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Bv() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.B*
- tail call void @_ZN1BC2Ev(%struct.B* %0)
- ret i8* %call
-}
-
-
-%struct.C = type { i32 (...)** }
-
-@_ZTV1C = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.C*)* @_ZN1C3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !4
-
-define internal void @_ZN1CC2Ev(%struct.C* %this) {
-entry:
- %0 = getelementptr inbounds %struct.C, %struct.C* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1C, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK-NOT: define {{.*}} @_ZN1C3fooEv(
-define internal void @_ZN1C3fooEv(%struct.C* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Cv() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.C*
- tail call void @_ZN1CC2Ev(%struct.C* %0)
- ret i8* %call
-}
-
-declare dso_local noalias nonnull i8* @_Znwm(i64)
-
-!llvm.module.flags = !{}
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFvvE.virtual"}
-!2 = !{i64 0} ; public vcall visibility
-!3 = !{i64 1} ; linkage-unit vcall visibility
-!4 = !{i64 2} ; translation-unit vcall visibility
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-declare dso_local noalias nonnull i8* @_Znwm(i64)
-declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata)
-
-; %struct.A is a C++ struct with two virtual functions, A::foo and A::bar. The
-; !vcall_visibility metadata is set on the vtable, so we know that all virtual
-; calls through this vtable are visible and use the @llvm.type.checked.load
-; intrinsic. Function test_A makes a call to A::foo, but there is no call to
-; A::bar anywhere, so A::bar can be deleted, and its vtable slot replaced with
-; null.
-
-%struct.A = type { i32 (...)** }
-
-; The pointer to A::bar in the vtable can be removed, because it will never be
-; loaded. We replace it with null to keep the layout the same. Because it is at
-; the end of the vtable we could potentially shrink the vtable, but don't
-; currently do that.
-; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*), i8* null] }
-@_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*), i8* bitcast (i32 (%struct.A*)* @_ZN1A3barEv to i8*)] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !3
-
-; A::foo is called, so must be retained.
-; CHECK: define internal i32 @_ZN1A3fooEv(
-define internal i32 @_ZN1A3fooEv(%struct.A* nocapture readnone %this) {
-entry:
- ret i32 42
-}
-
-; A::bar is not used, so can be deleted.
-; CHECK-NOT: define internal i32 @_ZN1A3barEv(
-define internal i32 @_ZN1A3barEv(%struct.A* nocapture readnone %this) {
-entry:
- ret i32 1337
-}
-
-define dso_local i32 @test_A() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.A*
- %1 = bitcast i8* %call to i32 (...)***
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %1, align 8
- %2 = tail call { i8*, i1 } @llvm.type.checked.load(i8* bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i8*), i32 0, metadata !"_ZTS1A"), !nosanitize !9
- %3 = extractvalue { i8*, i1 } %2, 0, !nosanitize !9
- %4 = bitcast i8* %3 to i32 (%struct.A*)*, !nosanitize !9
- %call1 = tail call i32 %4(%struct.A* nonnull %0)
- ret i32 %call1
-}
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFivE.virtual"}
-!2 = !{i64 24, !"_ZTSM1AFivE.virtual"}
-!3 = !{i64 2}
-!9 = !{}
+++ /dev/null
-; RUN: opt < %s -globaldce -S | FileCheck %s
-
-; We currently only use llvm.type.checked.load for virtual function pointers,
-; not any other part of the vtable, so we can't remove the RTTI pointer even if
-; it's never going to be loaded from.
-
-target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
-
-%struct.A = type { i32 (...)** }
-
-; CHECK: @_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* bitcast ({ i8*, i8* }* @_ZTI1A to i8*), i8* null] }, align 8, !type !0, !type !1, !vcall_visibility !2
-
-@_ZTV1A = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* bitcast ({ i8*, i8* }* @_ZTI1A to i8*), i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1, !vcall_visibility !2
-@_ZTS1A = hidden constant [3 x i8] c"1A\00", align 1
-@_ZTI1A = hidden constant { i8*, i8* } { i8* bitcast (i8** getelementptr inbounds (i8*, i8** @_ZTVN10__cxxabiv117__class_type_infoE, i64 2) to i8*), i8* getelementptr inbounds ([3 x i8], [3 x i8]* @_ZTS1A, i32 0, i32 0) }, align 8
-
-define internal void @_ZN1AC2Ev(%struct.A* %this) {
-entry:
- %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret void
-}
-
-; CHECK-NOT: define {{.*}} @_ZN1A3fooEv(
-define internal void @_ZN1A3fooEv(%struct.A* nocapture %this) {
-entry:
- ret void
-}
-
-define dso_local i8* @_Z6make_Av() {
-entry:
- %call = tail call i8* @_Znwm(i64 8)
- %0 = bitcast i8* %call to %struct.A*
- tail call void @_ZN1AC2Ev(%struct.A* %0)
- ret i8* %call
-}
-
-
-declare dso_local noalias nonnull i8* @_Znwm(i64)
-@_ZTVN10__cxxabiv117__class_type_infoE = external dso_local global i8*
-
-!llvm.module.flags = !{!3}
-
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFvvE.virtual"}
-!2 = !{i64 2} ; translation-unit vcall visibility
-!3 = !{i32 1, !"LTOPostLink", i32 1}
+++ /dev/null
-; RUN: opt < %s -internalize -S | FileCheck %s
-
-%struct.A = type { i32 (...)** }
-%struct.B = type { i32 (...)** }
-%struct.C = type { i32 (...)** }
-
-; Class A has default visibility, so has no !vcall_visibility metadata before
-; or after LTO.
-; CHECK-NOT: @_ZTV1A = {{.*}}!vcall_visibility
-@_ZTV1A = dso_local unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.A*)* @_ZN1A3fooEv to i8*)] }, align 8, !type !0, !type !1
-
-; Class B has hidden visibility but public LTO visibility, so has no
-; !vcall_visibility metadata before or after LTO.
-; CHECK-NOT: @_ZTV1B = {{.*}}!vcall_visibility
-@_ZTV1B = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.B*)* @_ZN1B3fooEv to i8*)] }, align 8, !type !2, !type !3
-
-; Class C has hidden visibility, so the !vcall_visibility metadata is set to 1
-; (linkage unit) before LTO, and 2 (translation unit) after LTO.
-; CHECK: @_ZTV1C ={{.*}}!vcall_visibility [[MD_TU_VIS:![0-9]+]]
-@_ZTV1C = hidden unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.C*)* @_ZN1C3fooEv to i8*)] }, align 8, !type !4, !type !5, !vcall_visibility !6
-
-; Class D has translation unit visibility before LTO, and this is not changed
-; by LTO.
-; CHECK: @_ZTVN12_GLOBAL__N_11DE = {{.*}}!vcall_visibility [[MD_TU_VIS:![0-9]+]]
-@_ZTVN12_GLOBAL__N_11DE = internal unnamed_addr constant { [3 x i8*] } zeroinitializer, align 8, !type !7, !type !9, !vcall_visibility !11
-
-define dso_local void @_ZN1A3fooEv(%struct.A* nocapture %this) {
-entry:
- ret void
-}
-
-define hidden void @_ZN1B3fooEv(%struct.B* nocapture %this) {
-entry:
- ret void
-}
-
-define hidden void @_ZN1C3fooEv(%struct.C* nocapture %this) {
-entry:
- ret void
-}
-
-define hidden noalias nonnull i8* @_Z6make_dv() {
-entry:
- %call = tail call i8* @_Znwm(i64 8) #3
- %0 = bitcast i8* %call to i32 (...)***
- store i32 (...)** bitcast (i8** getelementptr inbounds ({ [3 x i8*] }, { [3 x i8*] }* @_ZTVN12_GLOBAL__N_11DE, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
- ret i8* %call
-}
-
-declare dso_local noalias nonnull i8* @_Znwm(i64)
-
-; CHECK: [[MD_TU_VIS]] = !{i64 2}
-!0 = !{i64 16, !"_ZTS1A"}
-!1 = !{i64 16, !"_ZTSM1AFvvE.virtual"}
-!2 = !{i64 16, !"_ZTS1B"}
-!3 = !{i64 16, !"_ZTSM1BFvvE.virtual"}
-!4 = !{i64 16, !"_ZTS1C"}
-!5 = !{i64 16, !"_ZTSM1CFvvE.virtual"}
-!6 = !{i64 1}
-!7 = !{i64 16, !8}
-!8 = distinct !{}
-!9 = !{i64 16, !10}
-!10 = distinct !{}
-!11 = !{i64 2}
projects / platform / upstream / llvm.git / commitdiff