r245264 - Generating assumption loads of vptr after ctor call (fixed)

Piotr Padlewski via cfe-commits cfe-commits at lists.llvm.org
Mon Aug 17 23:12:10 PDT 2015


Thanks. I have no idea what happen, but I will fix it tomorrow.


Piotr

On Mon, Aug 17, 2015 at 10:43 PM, Justin Bogner <mail at justinbogner.com>
wrote:

> Piotr Padlewski via cfe-commits <cfe-commits at lists.llvm.org> writes:
> > Author: prazek
> > Date: Mon Aug 17 22:52:00 2015
> > New Revision: 245264
> >
> > URL: http://llvm.org/viewvc/llvm-project?rev=245264&view=rev
> > Log:
> > Generating assumption loads of vptr after ctor call (fixed)
> >
> > Generating call assume(icmp %vtable, %global_vtable) after constructor
> > call for devirtualization purposes.
> >
> > For more info go to:
> > http://lists.llvm.org/pipermail/cfe-dev/2015-July/044227.html
> >
> > Edit:
> > Fixed version because of PR24479.
>
> (resending since I foolishly sent a very large text file and it got
> caught in moderation)
>
> This was hitting asserts on a couple of bootstrap bots, so I reverted
> it in r245267.
>
> Failing bots:
>
> http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto_build/6382/
> http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/2969
>
> I also managed to grab the crash diagnostics from one of the bots, but
> the preprocessed source is too large for the list.
>
> > http://reviews.llvm.org/D11859
> >
> > Added:
> >     cfe/trunk/test/CodeGenCXX/vtable-assume-load.cpp
> > Modified:
> >     cfe/trunk/lib/CodeGen/CGCXXABI.h
> >     cfe/trunk/lib/CodeGen/CGCall.cpp
> >     cfe/trunk/lib/CodeGen/CGClass.cpp
> >     cfe/trunk/lib/CodeGen/CodeGenFunction.h
> >     cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
> >     cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
> >     cfe/trunk/test/CodeGen/available-externally-hidden.cpp
> >     cfe/trunk/test/CodeGenCXX/ctor-globalopt.cpp
> >     cfe/trunk/test/CodeGenCXX/template-instantiation.cpp
> >     cfe/trunk/test/CodeGenCXX/thunks.cpp
> >     cfe/trunk/test/CodeGenCXX/virtual-base-ctor.cpp
> >     cfe/trunk/test/CodeGenCXX/vtable-available-externally.cpp
> >
> > Modified: cfe/trunk/lib/CodeGen/CGCXXABI.h
> > URL:
> >
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCXXABI.h?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/CGCXXABI.h (original)
> > +++ cfe/trunk/lib/CodeGen/CGCXXABI.h Mon Aug 17 22:52:00 2015
> > @@ -346,13 +346,25 @@ public:
> >    virtual void emitVTableDefinitions(CodeGenVTables &CGVT,
> >                                       const CXXRecordDecl *RD) = 0;
> >
> > +  /// Checks if ABI requires extra virtual offset for vtable field.
> > +  virtual bool
> > +  isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
> > +                                      CodeGenFunction::VPtr Vptr) = 0;
> > +
> > +  /// Checks if ABI requires to initilize vptrs for given dynamic class.
> > +  virtual bool doStructorsInitializeVPtrs(const CXXRecordDecl
> *VTableClass) = 0;
> > +
> > +  /// Get the address point of the vtable for the given base subobject.
> > +  virtual llvm::Constant *
> > +  getVTableAddressPoint(BaseSubobject Base,
> > +                        const CXXRecordDecl *VTableClass) = 0;
> > +
> >    /// Get the address point of the vtable for the given base subobject
> while
> > -  /// building a constructor or a destructor. On return,
> NeedsVirtualOffset
> > -  /// tells if a virtual base adjustment is needed in order to get the
> offset
> > -  /// of the base subobject.
> > -  virtual llvm::Value *getVTableAddressPointInStructor(
> > -      CodeGenFunction &CGF, const CXXRecordDecl *RD, BaseSubobject Base,
> > -      const CXXRecordDecl *NearestVBase, bool &NeedsVirtualOffset) = 0;
> > +  /// building a constructor or a destructor.
> > +  virtual llvm::Value *
> > +  getVTableAddressPointInStructor(CodeGenFunction &CGF, const
> CXXRecordDecl *RD,
> > +                                  BaseSubobject Base,
> > +                                  const CXXRecordDecl *NearestVBase) =
> 0;
> >
> >    /// Get the address point of the vtable for the given base subobject
> while
> >    /// building a constexpr.
> >
> > Modified: cfe/trunk/lib/CodeGen/CGCall.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCall.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/CGCall.cpp (original)
> > +++ cfe/trunk/lib/CodeGen/CGCall.cpp Mon Aug 17 22:52:00 2015
> > @@ -1412,7 +1412,8 @@ void CodeGenModule::ConstructAttributeLi
> >
> >      if (const FunctionDecl *Fn = dyn_cast<FunctionDecl>(TargetDecl)) {
> >        const FunctionProtoType *FPT =
> Fn->getType()->getAs<FunctionProtoType>();
> > -      if (FPT && FPT->isNothrow(getContext()))
> > +      if (FPT &&
> !isUnresolvedExceptionSpec(FPT->getExceptionSpecType()) &&
> > +          FPT->isNothrow(getContext()))
> >          FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
> >        // Don't use [[noreturn]] or _Noreturn for a call to a virtual
> function.
> >        // These attributes are not inherited by overloads.
> >
> > Modified: cfe/trunk/lib/CodeGen/CGClass.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGClass.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/CGClass.cpp (original)
> > +++ cfe/trunk/lib/CodeGen/CGClass.cpp Mon Aug 17 22:52:00 2015
> > @@ -1806,12 +1806,14 @@ void CodeGenFunction::EmitCXXConstructor
> >                                               bool ForVirtualBase,
> >                                               bool Delegating,
> llvm::Value *This,
> >                                               const CXXConstructExpr *E)
> {
> > +  const CXXRecordDecl *ClassDecl = D->getParent();
> > +
> >    // C++11 [class.mfct.non-static]p2:
> >    //   If a non-static member function of a class X is called for an
> object that
> >    //   is not of type X, or of a type derived from X, the behavior is
> undefined.
> >    // FIXME: Provide a source location here.
> >    EmitTypeCheck(CodeGenFunction::TCK_ConstructorCall, SourceLocation(),
> This,
> > -                getContext().getRecordType(D->getParent()));
> > +                getContext().getRecordType(ClassDecl));
> >
> >    if (D->isTrivial() && D->isDefaultConstructor()) {
> >      assert(E->getNumArgs() == 0 && "trivial default ctor with args");
> > @@ -1827,7 +1829,7 @@ void CodeGenFunction::EmitCXXConstructor
> >      const Expr *Arg = E->getArg(0);
> >      QualType SrcTy = Arg->getType();
> >      llvm::Value *Src = EmitLValue(Arg).getAddress();
> > -    QualType DestTy = getContext().getTypeDeclType(D->getParent());
> > +    QualType DestTy = getContext().getTypeDeclType(ClassDecl);
> >      EmitAggregateCopyCtor(This, Src, DestTy, SrcTy);
> >      return;
> >    }
> > @@ -1850,6 +1852,41 @@ void CodeGenFunction::EmitCXXConstructor
> >    const CGFunctionInfo &Info =
> >        CGM.getTypes().arrangeCXXConstructorCall(Args, D, Type,
> ExtraArgs);
> >    EmitCall(Info, Callee, ReturnValueSlot(), Args, D);
> > +
> > +  // Generate vtable assumptions if we're constructing a complete object
> > +  // with a vtable.  We don't do this for base subobjects for two
> reasons:
> > +  // first, it's incorrect for classes with virtual bases, and second,
> we're
> > +  // about to overwrite the vptrs anyway.
> > +  if (CGM.getCodeGenOpts().OptimizationLevel > 0 &&
> > +      ClassDecl->isDynamicClass() && Type != Ctor_Base)
> > +    EmitVTableAssumptionLoads(ClassDecl, This);
> > +}
> > +
> > +void CodeGenFunction::EmitVTableAssumptionLoad(const VPtr &Vptr,
> > +                                               llvm::Value *This) {
> > +  llvm::Value *VTableGlobal =
> > +      CGM.getCXXABI().getVTableAddressPoint(Vptr.Base,
> Vptr.VTableClass);
> > +  if (!VTableGlobal)
> > +    return;
> > +
> > +  // We can just use the base offset in the complete class.
> > +  CharUnits NonVirtualOffset = Vptr.Base.getBaseOffset();
> > +
> > +  if (!NonVirtualOffset.isZero())
> > +    This =
> > +        ApplyNonVirtualAndVirtualOffset(*this, This, NonVirtualOffset,
> nullptr);
> > +
> > +  llvm::Value *VPtrValue = GetVTablePtr(This, VTableGlobal->getType());
> > +  llvm::Value *Cmp =
> > +      Builder.CreateICmpEQ(VPtrValue, VTableGlobal, "cmp.vtables");
> > +  Builder.CreateAssumption(Cmp);
> > +}
> > +
> > +void CodeGenFunction::EmitVTableAssumptionLoads(const CXXRecordDecl
> *ClassDecl,
> > +                                                llvm::Value *This) {
> > +  if (CGM.getCXXABI().doStructorsInitializeVPtrs(ClassDecl))
> > +    for (const VPtr &Vptr : getVTablePointers(ClassDecl))
> > +      EmitVTableAssumptionLoad(Vptr, This);
> >  }
> >
> >  void
> > @@ -2017,24 +2054,12 @@ void CodeGenFunction::PushDestructorClea
> >    PushDestructorCleanup(D, Addr);
> >  }
> >
> > -void
> > -CodeGenFunction::InitializeVTablePointer(BaseSubobject Base,
> > -                                         const CXXRecordDecl
> *NearestVBase,
> > -                                         CharUnits
> OffsetFromNearestVBase,
> > -                                         const CXXRecordDecl
> *VTableClass) {
> > -  const CXXRecordDecl *RD = Base.getBase();
> > -
> > -  // Don't initialize the vtable pointer if the class is marked with the
> > -  // 'novtable' attribute.
> > -  if ((RD == VTableClass || RD == NearestVBase) &&
> > -      VTableClass->hasAttr<MSNoVTableAttr>())
> > -    return;
> > -
> > +void CodeGenFunction::InitializeVTablePointer(const VPtr &Vptr) {
> >    // Compute the address point.
> > -  bool NeedsVirtualOffset;
> >    llvm::Value *VTableAddressPoint =
> >        CGM.getCXXABI().getVTableAddressPointInStructor(
> > -          *this, VTableClass, Base, NearestVBase, NeedsVirtualOffset);
> > +          *this, Vptr.VTableClass, Vptr.Base, Vptr.NearestVBase);
> > +
> >    if (!VTableAddressPoint)
> >      return;
> >
> > @@ -2042,17 +2067,15 @@ CodeGenFunction::InitializeVTablePointer
> >    llvm::Value *VirtualOffset = nullptr;
> >    CharUnits NonVirtualOffset = CharUnits::Zero();
> >
> > -  if (NeedsVirtualOffset) {
> > +  if (CGM.getCXXABI().isVirtualOffsetNeededForVTableField(*this, Vptr))
> {
> >      // We need to use the virtual base offset offset because the
> virtual base
> >      // might have a different offset in the most derived class.
> > -    VirtualOffset = CGM.getCXXABI().GetVirtualBaseClassOffset(*this,
> > -
> LoadCXXThis(),
> > -
> VTableClass,
> > -
> NearestVBase);
> > -    NonVirtualOffset = OffsetFromNearestVBase;
> > +    VirtualOffset = CGM.getCXXABI().GetVirtualBaseClassOffset(
> > +        *this, LoadCXXThis(), Vptr.VTableClass, Vptr.NearestVBase);
> > +    NonVirtualOffset = Vptr.OffsetFromNearestVBase;
> >    } else {
> >      // We can just use the base offset in the complete class.
> > -    NonVirtualOffset = Base.getBaseOffset();
> > +    NonVirtualOffset = Vptr.Base.getBaseOffset();
> >    }
> >
> >    // Apply the offsets.
> > @@ -2071,23 +2094,36 @@ CodeGenFunction::InitializeVTablePointer
> >            ->getPointerTo();
> >    VTableField = Builder.CreateBitCast(VTableField,
> VTablePtrTy->getPointerTo());
> >    VTableAddressPoint = Builder.CreateBitCast(VTableAddressPoint,
> VTablePtrTy);
> > +
> >    llvm::StoreInst *Store = Builder.CreateStore(VTableAddressPoint,
> VTableField);
> >    CGM.DecorateInstruction(Store, CGM.getTBAAInfoForVTablePtr());
> >  }
> >
> > -void
> > -CodeGenFunction::InitializeVTablePointers(BaseSubobject Base,
> > -                                          const CXXRecordDecl
> *NearestVBase,
> > -                                          CharUnits
> OffsetFromNearestVBase,
> > -                                          bool
> BaseIsNonVirtualPrimaryBase,
> > -                                          const CXXRecordDecl
> *VTableClass,
> > -                                          VisitedVirtualBasesSetTy&
> VBases) {
> > +CodeGenFunction::VPtrsVector
> > +CodeGenFunction::getVTablePointers(const CXXRecordDecl *VTableClass) {
> > +  CodeGenFunction::VPtrsVector VPtrsResult;
> > +  VisitedVirtualBasesSetTy VBases;
> > +  getVTablePointers(BaseSubobject(VTableClass, CharUnits::Zero()),
> > +                    /*NearestVBase=*/nullptr,
> > +                    /*OffsetFromNearestVBase=*/CharUnits::Zero(),
> > +                    /*BaseIsNonVirtualPrimaryBase=*/false, VTableClass,
> VBases,
> > +                    VPtrsResult);
> > +  return VPtrsResult;
> > +}
> > +
> > +void CodeGenFunction::getVTablePointers(BaseSubobject Base,
> > +                                        const CXXRecordDecl
> *NearestVBase,
> > +                                        CharUnits
> OffsetFromNearestVBase,
> > +                                        bool
> BaseIsNonVirtualPrimaryBase,
> > +                                        const CXXRecordDecl
> *VTableClass,
> > +                                        VisitedVirtualBasesSetTy
> &VBases,
> > +                                        VPtrsVector &Vptrs) {
> >    // If this base is a non-virtual primary base the address point has
> already
> >    // been set.
> >    if (!BaseIsNonVirtualPrimaryBase) {
> >      // Initialize the vtable pointer for this base.
> > -    InitializeVTablePointer(Base, NearestVBase, OffsetFromNearestVBase,
> > -                            VTableClass);
> > +    VPtr Vptr = {Base, NearestVBase, OffsetFromNearestVBase,
> VTableClass};
> > +    Vptrs.push_back(Vptr);
> >    }
> >
> >    const CXXRecordDecl *RD = Base.getBase();
> > @@ -2125,11 +2161,10 @@ CodeGenFunction::InitializeVTablePointer
> >        BaseDeclIsNonVirtualPrimaryBase = Layout.getPrimaryBase() ==
> BaseDecl;
> >      }
> >
> > -    InitializeVTablePointers(BaseSubobject(BaseDecl, BaseOffset),
> > -                             I.isVirtual() ? BaseDecl : NearestVBase,
> > -                             BaseOffsetFromNearestVBase,
> > -                             BaseDeclIsNonVirtualPrimaryBase,
> > -                             VTableClass, VBases);
> > +    getVTablePointers(
> > +        BaseSubobject(BaseDecl, BaseOffset),
> > +        I.isVirtual() ? BaseDecl : NearestVBase,
> BaseOffsetFromNearestVBase,
> > +        BaseDeclIsNonVirtualPrimaryBase, VTableClass, VBases, Vptrs);
> >    }
> >  }
> >
> > @@ -2139,11 +2174,9 @@ void CodeGenFunction::InitializeVTablePo
> >      return;
> >
> >    // Initialize the vtable pointers for this class and all of its bases.
> > -  VisitedVirtualBasesSetTy VBases;
> > -  InitializeVTablePointers(BaseSubobject(RD, CharUnits::Zero()),
> > -                           /*NearestVBase=*/nullptr,
> > -                           /*OffsetFromNearestVBase=*/CharUnits::Zero(),
> > -                           /*BaseIsNonVirtualPrimaryBase=*/false, RD,
> VBases);
> > +  if (CGM.getCXXABI().doStructorsInitializeVPtrs(RD))
> > +    for (const VPtr &Vptr : getVTablePointers(RD))
> > +      InitializeVTablePointer(Vptr);
> >
> >    if (RD->getNumVBases())
> >      CGM.getCXXABI().initializeHiddenVirtualInheritanceMembers(*this,
> RD);
> >
> > Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
> > +++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Mon Aug 17 22:52:00 2015
> > @@ -1309,21 +1309,27 @@ public:
> >    void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init,
> >                                 ArrayRef<VarDecl *> ArrayIndexes);
> >
> > -  /// InitializeVTablePointer - Initialize the vtable pointer of the
> given
> > -  /// subobject.
> > -  ///
> > -  void InitializeVTablePointer(BaseSubobject Base,
> > -                               const CXXRecordDecl *NearestVBase,
> > -                               CharUnits OffsetFromNearestVBase,
> > -                               const CXXRecordDecl *VTableClass);
> > +  /// Struct with all informations about dynamic [sub]class needed to
> set vptr.
> > +  struct VPtr {
> > +    BaseSubobject Base;
> > +    const CXXRecordDecl *NearestVBase;
> > +    CharUnits OffsetFromNearestVBase;
> > +    const CXXRecordDecl *VTableClass;
> > +  };
> > +
> > +  /// Initialize the vtable pointer of the given subobject.
> > +  void InitializeVTablePointer(const VPtr &vptr);
> > +
> > +  typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
> >
> >    typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4>
> VisitedVirtualBasesSetTy;
> > -  void InitializeVTablePointers(BaseSubobject Base,
> > -                                const CXXRecordDecl *NearestVBase,
> > -                                CharUnits OffsetFromNearestVBase,
> > -                                bool BaseIsNonVirtualPrimaryBase,
> > -                                const CXXRecordDecl *VTableClass,
> > -                                VisitedVirtualBasesSetTy& VBases);
> > +  VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
> > +
> > +  void getVTablePointers(BaseSubobject Base, const CXXRecordDecl
> *NearestVBase,
> > +                         CharUnits OffsetFromNearestVBase,
> > +                         bool BaseIsNonVirtualPrimaryBase,
> > +                         const CXXRecordDecl *VTableClass,
> > +                         VisitedVirtualBasesSetTy &VBases, VPtrsVector
> &vptrs);
> >
> >    void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
> >
> > @@ -1752,10 +1758,19 @@ public:
> >    // they are substantially the same.
> >    void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
> >                                          const FunctionArgList &Args);
> > +
> >    void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType
> Type,
> >                                bool ForVirtualBase, bool Delegating,
> >                                llvm::Value *This, const CXXConstructExpr
> *E);
> >
> > +  /// Emit assumption load for all bases. Requires to be be called only
> on
> > +  /// most-derived class and not under construction of the object.
> > +  void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl,
> > +                                 llvm::Value *This);
> > +
> > +  /// Emit assumption that vptr load == global vtable.
> > +  void EmitVTableAssumptionLoad(const VPtr &vptr, llvm::Value *This);
> > +
> >    void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
> >                                llvm::Value *This, llvm::Value *Src,
> >                                const CXXConstructExpr *E);
> >
> > Modified: cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp (original)
> > +++ cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp Mon Aug 17 22:52:00 2015
> > @@ -190,10 +190,24 @@ public:
> >    void emitVTableDefinitions(CodeGenVTables &CGVT,
> >                               const CXXRecordDecl *RD) override;
> >
> > +  bool isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
> > +                                           CodeGenFunction::VPtr Vptr)
> override;
> > +
> > +  bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass)
> override {
> > +    return true;
> > +  }
> > +
> > +  llvm::Constant *
> > +  getVTableAddressPoint(BaseSubobject Base,
> > +                        const CXXRecordDecl *VTableClass) override;
> > +
> >    llvm::Value *getVTableAddressPointInStructor(
> >        CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> > -      BaseSubobject Base, const CXXRecordDecl *NearestVBase,
> > -      bool &NeedsVirtualOffset) override;
> > +      BaseSubobject Base, const CXXRecordDecl *NearestVBase) override;
> > +
> > +  llvm::Value *getVTableAddressPointInStructorWithVTT(
> > +      CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> > +      BaseSubobject Base, const CXXRecordDecl *NearestVBase);
> >
> >    llvm::Constant *
> >    getVTableAddressPointForConstExpr(BaseSubobject Base,
> > @@ -1376,41 +1390,29 @@ void ItaniumCXXABI::emitVTableDefinition
> >    CGM.EmitVTableBitSetEntries(VTable, VTLayout);
> >  }
> >
> > +bool ItaniumCXXABI::isVirtualOffsetNeededForVTableField(
> > +    CodeGenFunction &CGF, CodeGenFunction::VPtr Vptr) {
> > +  if (Vptr.NearestVBase == nullptr)
> > +    return false;
> > +  return NeedsVTTParameter(CGF.CurGD);
> > +}
> > +
> >  llvm::Value *ItaniumCXXABI::getVTableAddressPointInStructor(
> >      CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> BaseSubobject Base,
> > -    const CXXRecordDecl *NearestVBase, bool &NeedsVirtualOffset) {
> > -  bool NeedsVTTParam = CGM.getCXXABI().NeedsVTTParameter(CGF.CurGD);
> > -  NeedsVirtualOffset = (NeedsVTTParam && NearestVBase);
> > -
> > -  llvm::Value *VTableAddressPoint;
> > -  if (NeedsVTTParam && (Base.getBase()->getNumVBases() ||
> NearestVBase)) {
> > -    // Get the secondary vpointer index.
> > -    uint64_t VirtualPointerIndex =
> > -        CGM.getVTables().getSecondaryVirtualPointerIndex(VTableClass,
> Base);
> > -
> > -    /// Load the VTT.
> > -    llvm::Value *VTT = CGF.LoadCXXVTT();
> > -    if (VirtualPointerIndex)
> > -      VTT = CGF.Builder.CreateConstInBoundsGEP1_64(VTT,
> VirtualPointerIndex);
> > +    const CXXRecordDecl *NearestVBase) {
> >
> > -    // And load the address point from the VTT.
> > -    VTableAddressPoint = CGF.Builder.CreateLoad(VTT);
> > -  } else {
> > -    llvm::Constant *VTable =
> > -        CGM.getCXXABI().getAddrOfVTable(VTableClass, CharUnits());
> > -    uint64_t AddressPoint = CGM.getItaniumVTableContext()
> > -                                .getVTableLayout(VTableClass)
> > -                                .getAddressPoint(Base);
> > -    VTableAddressPoint =
> > -        CGF.Builder.CreateConstInBoundsGEP2_64(VTable, 0, AddressPoint);
> > +  if ((Base.getBase()->getNumVBases() || NearestVBase != nullptr) &&
> > +      NeedsVTTParameter(CGF.CurGD)) {
> > +    return getVTableAddressPointInStructorWithVTT(CGF, VTableClass,
> Base,
> > +                                                  NearestVBase);
> >    }
> > -
> > -  return VTableAddressPoint;
> > +  return getVTableAddressPoint(Base, VTableClass);
> >  }
> >
> > -llvm::Constant *ItaniumCXXABI::getVTableAddressPointForConstExpr(
> > -    BaseSubobject Base, const CXXRecordDecl *VTableClass) {
> > -  auto *VTable = getAddrOfVTable(VTableClass, CharUnits());
> > +llvm::Constant *
> > +ItaniumCXXABI::getVTableAddressPoint(BaseSubobject Base,
> > +                                     const CXXRecordDecl *VTableClass) {
> > +  llvm::GlobalValue *VTable = getAddrOfVTable(VTableClass, CharUnits());
> >
> >    // Find the appropriate vtable within the vtable group.
> >    uint64_t AddressPoint = CGM.getItaniumVTableContext()
> > @@ -1425,6 +1427,30 @@ llvm::Constant *ItaniumCXXABI::getVTable
> >                                                        VTable, Indices);
> >  }
> >
> > +llvm::Value *ItaniumCXXABI::getVTableAddressPointInStructorWithVTT(
> > +    CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> BaseSubobject Base,
> > +    const CXXRecordDecl *NearestVBase) {
> > +  assert((Base.getBase()->getNumVBases() || NearestVBase != nullptr) &&
> > +         NeedsVTTParameter(CGF.CurGD) && "This class doesn't have VTT");
> > +
> > +  // Get the secondary vpointer index.
> > +  uint64_t VirtualPointerIndex =
> > +      CGM.getVTables().getSecondaryVirtualPointerIndex(VTableClass,
> Base);
> > +
> > +  /// Load the VTT.
> > +  llvm::Value *VTT = CGF.LoadCXXVTT();
> > +  if (VirtualPointerIndex)
> > +    VTT = CGF.Builder.CreateConstInBoundsGEP1_64(VTT,
> VirtualPointerIndex);
> > +
> > +  // And load the address point from the VTT.
> > +  return CGF.Builder.CreateLoad(VTT);
> > +}
> > +
> > +llvm::Constant *ItaniumCXXABI::getVTableAddressPointForConstExpr(
> > +    BaseSubobject Base, const CXXRecordDecl *VTableClass) {
> > +  return getVTableAddressPoint(Base, VTableClass);
> > +}
> > +
> >  llvm::GlobalVariable *ItaniumCXXABI::getAddrOfVTable(const
> CXXRecordDecl *RD,
> >                                                       CharUnits
> VPtrOffset) {
> >    assert(VPtrOffset.isZero() && "Itanium ABI only supports zero vptr
> offsets");
> >
> > Modified: cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp (original)
> > +++ cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp Mon Aug 17 22:52:00 2015
> > @@ -215,10 +215,22 @@ public:
> >    void emitVTableDefinitions(CodeGenVTables &CGVT,
> >                               const CXXRecordDecl *RD) override;
> >
> > +  bool isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
> > +                                           CodeGenFunction::VPtr Vptr)
> override;
> > +
> > +  /// Don't initialize vptrs if dynamic class
> > +  /// is marked with with the 'novtable' attribute.
> > +  bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass)
> override {
> > +    return !VTableClass->hasAttr<MSNoVTableAttr>();
> > +  }
> > +
> > +  llvm::Constant *
> > +  getVTableAddressPoint(BaseSubobject Base,
> > +                        const CXXRecordDecl *VTableClass) override;
> > +
> >    llvm::Value *getVTableAddressPointInStructor(
> >        CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> > -      BaseSubobject Base, const CXXRecordDecl *NearestVBase,
> > -      bool &NeedsVirtualOffset) override;
> > +      BaseSubobject Base, const CXXRecordDecl *NearestVBase) override;
> >
> >    llvm::Constant *
> >    getVTableAddressPointForConstExpr(BaseSubobject Base,
> > @@ -1568,14 +1580,15 @@ void MicrosoftCXXABI::emitVTableDefiniti
> >    }
> >  }
> >
> > +bool MicrosoftCXXABI::isVirtualOffsetNeededForVTableField(
> > +    CodeGenFunction &CGF, CodeGenFunction::VPtr Vptr) {
> > +  return Vptr.NearestVBase != nullptr;
> > +}
> > +
> >  llvm::Value *MicrosoftCXXABI::getVTableAddressPointInStructor(
> >      CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
> BaseSubobject Base,
> > -    const CXXRecordDecl *NearestVBase, bool &NeedsVirtualOffset) {
> > -  NeedsVirtualOffset = (NearestVBase != nullptr);
> > -
> > -  (void)getAddrOfVTable(VTableClass, Base.getBaseOffset());
> > -  VFTableIdTy ID(VTableClass, Base.getBaseOffset());
> > -  llvm::GlobalValue *VTableAddressPoint = VFTablesMap[ID];
> > +    const CXXRecordDecl *NearestVBase) {
> > +  llvm::Constant *VTableAddressPoint = getVTableAddressPoint(Base,
> VTableClass);
> >    if (!VTableAddressPoint) {
> >      assert(Base.getBase()->getNumVBases() &&
> >
>  !getContext().getASTRecordLayout(Base.getBase()).hasOwnVFPtr());
> > @@ -1590,11 +1603,17 @@ static void mangleVFTableName(MicrosoftM
> >    MangleContext.mangleCXXVFTable(RD, VFPtr->MangledPath, Out);
> >  }
> >
> > -llvm::Constant *MicrosoftCXXABI::getVTableAddressPointForConstExpr(
> > -    BaseSubobject Base, const CXXRecordDecl *VTableClass) {
> > +llvm::Constant *
> > +MicrosoftCXXABI::getVTableAddressPoint(BaseSubobject Base,
> > +                                       const CXXRecordDecl
> *VTableClass) {
> >    (void)getAddrOfVTable(VTableClass, Base.getBaseOffset());
> >    VFTableIdTy ID(VTableClass, Base.getBaseOffset());
> > -  llvm::GlobalValue *VFTable = VFTablesMap[ID];
> > +  return VFTablesMap[ID];
> > +}
> > +
> > +llvm::Constant *MicrosoftCXXABI::getVTableAddressPointForConstExpr(
> > +    BaseSubobject Base, const CXXRecordDecl *VTableClass) {
> > +  llvm::Constant *VFTable = getVTableAddressPoint(Base, VTableClass);
> >    assert(VFTable && "Couldn't find a vftable for the given base?");
> >    return VFTable;
> >  }
> > @@ -1604,6 +1623,7 @@ llvm::GlobalVariable *MicrosoftCXXABI::g
> >    // getAddrOfVTable may return 0 if asked to get an address of a
> vtable which
> >    // shouldn't be used in the given record type. We want to cache this
> result in
> >    // VFTablesMap, thus a simple zero check is not sufficient.
> > +
> >    VFTableIdTy ID(RD, VPtrOffset);
> >    VTablesMapTy::iterator I;
> >    bool Inserted;
> > @@ -1657,10 +1677,11 @@ llvm::GlobalVariable *MicrosoftCXXABI::g
> >    if (llvm::GlobalValue *VFTable =
> >            CGM.getModule().getNamedGlobal(VFTableName)) {
> >      VFTablesMap[ID] = VFTable;
> > -    return VTableAliasIsRequred
> > -               ? cast<llvm::GlobalVariable>(
> > -                     cast<llvm::GlobalAlias>(VFTable)->getBaseObject())
> > -               : cast<llvm::GlobalVariable>(VFTable);
> > +    VTable = VTableAliasIsRequred
> > +                 ? cast<llvm::GlobalVariable>(
> > +
>  cast<llvm::GlobalAlias>(VFTable)->getBaseObject())
> > +                 : cast<llvm::GlobalVariable>(VFTable);
> > +    return VTable;
> >    }
> >
> >    uint64_t NumVTableSlots =
> >
> > Modified: cfe/trunk/test/CodeGen/available-externally-hidden.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/available-externally-hidden.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGen/available-externally-hidden.cpp (original)
> > +++ cfe/trunk/test/CodeGen/available-externally-hidden.cpp Mon Aug 17
> 22:52:00 2015
> > @@ -27,6 +27,6 @@ class TestSyncMessageFilter : public Syn
> >  };
> >
> >  int main() {
> > -TestSyncMessageFilter*  f = new TestSyncMessageFilter;
> > +  TestSyncMessageFilter *f = new TestSyncMessageFilter;
> >    f->Send(new Message);
> >  }
> >
> > Modified: cfe/trunk/test/CodeGenCXX/ctor-globalopt.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/ctor-globalopt.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/ctor-globalopt.cpp (original)
> > +++ cfe/trunk/test/CodeGenCXX/ctor-globalopt.cpp Mon Aug 17 22:52:00 2015
> > @@ -1,7 +1,7 @@
> >  // RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -o - %s |
> FileCheck %s
> > -// RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -o - %s -O1 |
> FileCheck %s --check-prefix=O1
> > +// RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -o - %s -O2 |
> opt - -S -globalopt -o - | FileCheck %s --check-prefix=O1
> >  // RUN: %clang_cc1 -triple %ms_abi_triple -emit-llvm -o - %s |
> FileCheck %s
> > -// RUN: %clang_cc1 -triple %ms_abi_triple -emit-llvm -o - %s -O1 |
> FileCheck %s --check-prefix=O1
> > +// RUN: %clang_cc1 -triple %ms_abi_triple -emit-llvm -o - %s -O2 | opt
> - -S -globalopt -o - | FileCheck %s --check-prefix=O1
> >
> >  // Check that GlobalOpt can eliminate static constructors for simple
> implicit
> >  // constructors. This is a targetted integration test to make sure that
> LLVM's
> >
> > Modified: cfe/trunk/test/CodeGenCXX/template-instantiation.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/template-instantiation.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/template-instantiation.cpp (original)
> > +++ cfe/trunk/test/CodeGenCXX/template-instantiation.cpp Mon Aug 17
> 22:52:00 2015
> > @@ -1,5 +1,7 @@
> >  // RUN: %clang_cc1 %s -O1 -disable-llvm-optzns
> -triple=x86_64-apple-darwin10 -emit-llvm -o - | FileCheck %s
> >
> > +// CHECK:     @_ZTVN5test018stdio_sync_filebufIA4_iEE = linkonce_odr
> unnamed_addr constant
> > +
> >  // CHECK: @_ZN7PR100011xE = global
> >  // CHECK-NOT: @_ZN7PR100014kBarE = external global i32
> >  //
> > @@ -12,7 +14,6 @@
> >  // CHECK: @_ZN7PR100011SIiE3arrE = linkonce_odr global [3 x i32]
> >  // CHECK-NOT: @_ZN7PR100011SIiE3arr2E = linkonce_odr global [3 x i32]A
> >
> > -// CHECK:     @_ZTVN5test018stdio_sync_filebufIA4_iEE = linkonce_odr
> unnamed_addr constant
> >
> >  // CHECK-NOT: _ZTVN5test31SIiEE
> >  // CHECK-NOT: _ZTSN5test31SIiEE
> >
> > Modified: cfe/trunk/test/CodeGenCXX/thunks.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/thunks.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/thunks.cpp (original)
> > +++ cfe/trunk/test/CodeGenCXX/thunks.cpp Mon Aug 17 22:52:00 2015
> > @@ -1,5 +1,9 @@
> > -// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables
> -emit-llvm -o - | FileCheck %s
> > -// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables
> -emit-llvm -o - -O1 -disable-llvm-optzns | FileCheck %s
> > +// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables
> -emit-llvm -o %t
> > +// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables
> -emit-llvm -o %t.opt -O1 -disable-llvm-optzns
> > +// RUN: FileCheck %s < %t
> > +// RUN: FileCheck %s < %t.opt
> > +// RUN: FileCheck --check-prefix=CHECK-NONOPT %s < %t
> > +// RUN: FileCheck --check-prefix=CHECK-OPT %s < %t.opt
> >
> >  namespace Test1 {
> >
> > @@ -380,13 +384,25 @@ D::~D() {}
> >
> >  /**** The following has to go at the end of the file ****/
> >
> > +// checking without opt
> > +// CHECK-NONOPT-LABEL: define internal void
> @_ZThn8_N6Test4B12_GLOBAL__N_11C1fEv(
> > +// CHECK-NONOPT-NOT: comdat
> > +
> >  // This is from Test5:
> > -// CHECK-LABEL: define internal void
> @_ZThn8_N6Test4B12_GLOBAL__N_11C1fEv(
> > -// CHECK-NOT: comdat
> > -// CHECK-LABEL: define linkonce_odr void @_ZTv0_n24_N5Test51B1fEv
> > +// CHECK-NONOPT-LABEL: define linkonce_odr void @_ZTv0_n24_N5Test51B1fEv
> > +
> > +// This is from Test10:
> > +// CHECK-NONOPT-LABEL: define linkonce_odr void @_ZN6Test101C3fooEv
> > +// CHECK-NONOPT-LABEL: define linkonce_odr void @_ZThn8_N6Test101C3fooEv
> > +
> > +// Checking with opt
> > +// CHECK-OPT-LABEL: define internal void
> @_ZThn8_N6Test4B12_GLOBAL__N_11C1fEv(%"struct.Test4B::(anonymous
> namespace)::C"* %this) unnamed_addr #0 align 2
> >
> >  // This is from Test10:
> > -// CHECK-LABEL: define linkonce_odr void @_ZN6Test101C3fooEv
> > -// CHECK-LABEL: define linkonce_odr void @_ZThn8_N6Test101C3fooEv
> > +// CHECK-OPT-LABEL: define linkonce_odr void @_ZN6Test101C3fooEv
> > +// CHECK-OPT-LABEL: define linkonce_odr void @_ZThn8_N6Test101C3fooEv
> > +
> > +// This is from Test5:
> > +// CHECK-OPT-LABEL: define linkonce_odr void @_ZTv0_n24_N5Test51B1fEv
> >
> >  // CHECK: attributes [[NUW]] = { nounwind uwtable{{.*}} }
> >
> > Modified: cfe/trunk/test/CodeGenCXX/virtual-base-ctor.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/virtual-base-ctor.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/virtual-base-ctor.cpp (original)
> > +++ cfe/trunk/test/CodeGenCXX/virtual-base-ctor.cpp Mon Aug 17 22:52:00
> 2015
> > @@ -1,4 +1,4 @@
> > -// RUN: %clang_cc1 %s -emit-llvm -triple %itanium_abi_triple -o - -O2 |
> FileCheck %s
> > +// RUN: %clang_cc1 %s -emit-llvm -triple %itanium_abi_triple -o - -O2 |
> opt - -S -globalopt -o - | FileCheck %s
> >
> >  struct B;
> >  extern B x;
> >
> > Added: cfe/trunk/test/CodeGenCXX/vtable-assume-load.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/vtable-assume-load.cpp?rev=245264&view=auto
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/vtable-assume-load.cpp (added)
> > +++ cfe/trunk/test/CodeGenCXX/vtable-assume-load.cpp Mon Aug 17 22:52:00
> 2015
> > @@ -0,0 +1,172 @@
> > +// RUN: %clang_cc1 %s -triple x86_64-apple-darwin10 -emit-llvm -o %t.ll
> -O1 -disable-llvm-optzns -fms-extensions
> > +// RUN: %clang_cc1 %s -triple i686-pc-win32 -emit-llvm -o %t.ms.ll -O1
> -disable-llvm-optzns -fms-extensions
> > +
> > +// RUN: FileCheck --check-prefix=CHECK1 --input-file=%t.ll %s
> > +// RUN: FileCheck --check-prefix=CHECK2 --input-file=%t.ll %s
> > +// RUN: FileCheck --check-prefix=CHECK3 --input-file=%t.ll %s
> > +// RUN: FileCheck --check-prefix=CHECK4 --input-file=%t.ll %s
> > +// RUN: FileCheck --check-prefix=CHECK-MS --input-file=%t.ms.ll %s
> > +
> > +namespace test1 {
> > +
> > +struct A {
> > +  A();
> > +  virtual void foo();
> > +};
> > +
> > +struct B : A {
> > +  virtual void foo();
> > +};
> > +
> > +void g(A *a) { a->foo(); }
> > +
> > +// CHECK1-LABEL: define void @_ZN5test14fooAEv()
> > +// CHECK1: call void @_ZN5test11AC1Ev(%"struct.test1::A"*
> > +// CHECK1: %[[VTABLE:.*]] = load i8**, i8*** %{{.*}}
> > +// CHECK1: %[[CMP:.*]] = icmp eq i8** %[[VTABLE]], getelementptr
> inbounds ([3 x i8*], [3 x i8*]* @_ZTVN5test11AE, i64 0, i64 2)
> > +// CHECK1: call void @llvm.assume(i1 %[[CMP]])
> > +// CHECK1-LABEL: }
> > +
> > +void fooA() {
> > +  A a;
> > +  g(&a);
> > +}
> > +
> > +// CHECK1-LABEL: define void @_ZN5test14fooBEv()
> > +// CHECK1: call void @_ZN5test11BC1Ev(%"struct.test1::B"* %{{.*}})
> > +// CHECK1: %[[VTABLE:.*]] = load i8**, i8*** %{{.*}}
> > +// CHECK1: %[[CMP:.*]] = icmp eq i8** %[[VTABLE]], getelementptr
> inbounds ([3 x i8*], [3 x i8*]* @_ZTVN5test11BE, i64 0, i64 2)
> > +// CHECK1: call void @llvm.assume(i1 %[[CMP]])
> > +// CHECK1-LABEL: }
> > +
> > +void fooB() {
> > +  B b;
> > +  g(&b);
> > +}
> > +// there should not be any assumes in the ctor that calls base ctor
> > +// CHECK1-LABEL: define linkonce_odr void
> @_ZN5test11BC2Ev(%"struct.test1::B"*
> > +// CHECK1-NOT: @llvm.assume(
> > +// CHECK1-LABEL: }
> > +}
> > +namespace test2 {
> > +struct A {
> > +  A();
> > +  virtual void foo();
> > +};
> > +
> > +struct B {
> > +  B();
> > +  virtual void bar();
> > +};
> > +
> > +struct C : A, B {
> > +  C();
> > +  virtual void foo();
> > +};
> > +void g(A *a) { a->foo(); }
> > +void h(B *b) { b->bar(); }
> > +
> > +// CHECK2-LABEL: define void @_ZN5test24testEv()
> > +// CHECK2: call void @_ZN5test21CC1Ev(%"struct.test2::C"*
> > +// CHECK2: %[[VTABLE:.*]] = load i8**, i8*** {{.*}}
> > +// CHECK2: %[[CMP:.*]] = icmp eq i8** %[[VTABLE]], getelementptr
> inbounds ([6 x i8*], [6 x i8*]* @_ZTVN5test21CE, i64 0, i64 2)
> > +// CHECK2: call void @llvm.assume(i1 %[[CMP]])
> > +
> > +// CHECK2: %[[V2:.*]] = bitcast %"struct.test2::C"* %{{.*}} to i8*
> > +// CHECK2: %[[ADD_PTR:.*]] = getelementptr inbounds i8, i8* %[[V2]],
> i64 8
> > +// CHECK2: %[[V3:.*]] = bitcast i8* %[[ADD_PTR]] to i8***
> > +// CHECK2: %[[VTABLE2:.*]] = load i8**, i8*** %[[V3]]
> > +// CHECK2: %[[CMP2:.*]] = icmp eq i8** %[[VTABLE2]], getelementptr
> inbounds ([6 x i8*], [6 x i8*]* @_ZTVN5test21CE, i64 0, i64 5)
> > +// CHECK2: call void @llvm.assume(i1 %[[CMP2]])
> > +
> > +// CHECK2: call void @_ZN5test21gEPNS_1AE(
> > +// CHECK2-LABEL: }
> > +
> > +void test() {
> > +  C c;
> > +  g(&c);
> > +  h(&c);
> > +}
> > +}
> > +
> > +namespace test3 {
> > +struct A {
> > +  A();
> > +};
> > +
> > +struct B : A {
> > +  B();
> > +  virtual void foo();
> > +};
> > +
> > +struct C : virtual A, B {
> > +  C();
> > +  virtual void foo();
> > +};
> > +void g(B *a) { a->foo(); }
> > +
> > +// CHECK3-LABEL: define void @_ZN5test34testEv()
> > +// CHECK3: call void @_ZN5test31CC1Ev(%"struct.test3::C"*
> > +// CHECK3: %[[CMP:.*]] = icmp eq i8** %{{.*}}, getelementptr inbounds
> ([4 x i8*], [4 x i8*]* @_ZTVN5test31CE, i64 0, i64 3)
> > +// CHECK3: call void @llvm.assume(i1 %[[CMP]])
> > +// CHECK3-LABLEL: }
> > +void test() {
> > +  C c;
> > +  g(&c);
> > +}
> > +} // test3
> > +
> > +namespace test4 {
> > +struct A {
> > +  A();
> > +  virtual void foo();
> > +};
> > +
> > +struct B : virtual A {
> > +  B();
> > +  virtual void foo();
> > +};
> > +struct C : B {
> > +  C();
> > +  virtual void foo();
> > +};
> > +
> > +void g(C *c) { c->foo(); }
> > +
> > +// CHECK4-LABEL: define void @_ZN5test44testEv()
> > +// CHECK4: call void @_ZN5test41CC1Ev(%"struct.test4::C"*
> > +// CHECK4: %[[VTABLE:.*]] = load i8**, i8*** %{{.*}}
> > +// CHECK4: %[[CMP:.*]] = icmp eq i8** %[[VTABLE]], getelementptr
> inbounds ([5 x i8*], [5 x i8*]* @_ZTVN5test41CE, i64 0, i64 4)
> > +// CHECK4: call void @llvm.assume(i1 %[[CMP]]
> > +
> > +// CHECK4: %[[VTABLE2:.*]] = load i8**, i8*** %{{.*}}
> > +// CHECK4: %[[CMP2:.*]] = icmp eq i8** %[[VTABLE2]], getelementptr
> inbounds ([5 x i8*], [5 x i8*]* @_ZTVN5test41CE, i64 0, i64 4)
> > +// CHECK4: call void @llvm.assume(i1 %[[CMP2]])
> > +// CHECK4-LABEL: }
> > +
> > +void test() {
> > +  C c;
> > +  g(&c);
> > +}
> > +} // test4
> > +
> > +namespace test5 {
> > +
> > +struct __declspec(novtable) S {
> > +  virtual void foo();
> > +};
> > +
> > +void g(S &s) { s.foo(); }
> > +
> > +// if struct has novtable specifier, then we can't generate assumes
> > +// CHECK-MS-LABEL: define void @"\01?test at test5@@YAXXZ"()
> > +// CHECK-MS: call x86_thiscallcc %"struct.test5::S"* @"\01??0S at test5
> @@QAE at XZ"(
> > +// CHECK-MS-NOT: @llvm.assume
> > +// CHECK-MS-LABEL: }
> > +
> > +void test() {
> > +  S s;
> > +  g(s);
> > +}
> > +
> > +} // test5
> >
> > Modified: cfe/trunk/test/CodeGenCXX/vtable-available-externally.cpp
> > URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/vtable-available-externally.cpp?rev=245264&r1=245263&r2=245264&view=diff
> >
> ==============================================================================
> > --- cfe/trunk/test/CodeGenCXX/vtable-available-externally.cpp (original)
> > +++ cfe/trunk/test/CodeGenCXX/vtable-available-externally.cpp Mon Aug 17
> 22:52:00 2015
> > @@ -182,8 +182,8 @@ void f() {
> >  namespace Test9 {
> >  // all virtual functions are outline, so we can assume that it will
> >  // be generated in translation unit where foo is defined
> > -// CHECK-TEST9: @_ZTVN5Test91AE = available_externally unnamed_addr
> constant
> > -// CHECK-TEST9: @_ZTVN5Test91BE = available_externally unnamed_addr
> constant
> > +// CHECK-TEST9-DAG: @_ZTVN5Test91AE = available_externally unnamed_addr
> constant
> > +// CHECK-TEST9-DAG: @_ZTVN5Test91BE = available_externally unnamed_addr
> constant
> >  struct A {
> >    virtual void foo();
> >    virtual void bar();
> > @@ -206,7 +206,7 @@ void g() {
> >  namespace Test10 {
> >
> >  // because A's key function is defined here, vtable is generated in
> this TU
> > -// CHECK-TEST10: @_ZTVN6Test101AE = unnamed_addr constant
> > +// CHECK-TEST10-DAG: @_ZTVN6Test101AE = unnamed_addr constant
> >  struct A {
> >    virtual void foo();
> >    virtual void bar();
> > @@ -214,14 +214,14 @@ struct A {
> >  void A::foo() {}
> >
> >  // Because key function is inline we will generate vtable as
> linkonce_odr
> > -// CHECK-TEST10: @_ZTVN6Test101DE = linkonce_odr unnamed_addr constant
> > +// CHECK-TEST10-DAG: @_ZTVN6Test101DE = linkonce_odr unnamed_addr
> constant
> >  struct D : A {
> >    void bar();
> >  };
> >  inline void D::bar() {}
> >
> >  // because B has outline key function then we can refer to
> > -// CHECK-TEST10: @_ZTVN6Test101BE = available_externally unnamed_addr
> constant
> > +// CHECK-TEST10-DAG: @_ZTVN6Test101BE = available_externally
> unnamed_addr constant
> >  struct B : A {
> >    void foo();
> >    void bar();
> > @@ -230,7 +230,7 @@ struct B : A {
> >  // C's key function (car) is outline, but C has inline virtual function
> so we
> >  // can't guarantee that we will be able to refer to bar from name
> >  // so (at the moment) we can't emit vtable available_externally
> > -// CHECK-TEST10: @_ZTVN6Test101CE = external unnamed_addr constant
> > +// CHECK-TEST10-DAG: @_ZTVN6Test101CE = external unnamed_addr constant
> >  struct C : A {
> >    void bar() {}               // defined in body - not key function
> >    virtual inline void gar();  // inline in body - not key function
> > @@ -238,7 +238,7 @@ struct C : A {
> >  };
> >
> >  // no key function, vtable will be generated everywhere it will be used
> > -// CHECK-TEST10: @_ZTVN6Test101EE = linkonce_odr unnamed_addr constant
> > +// CHECK-TEST10-DAG: @_ZTVN6Test101EE = linkonce_odr unnamed_addr
> constant
> >  struct E : A {};
> >
> >  void g(A& a) {
> >
> >
> > _______________________________________________
> > cfe-commits mailing list
> > cfe-commits at lists.llvm.org
> > http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>
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