From: Anders Carlsson Date: Fri, 11 Dec 2009 02:46:30 +0000 (+0000) Subject: Improve linkage of RTTI data structures. Introduce CodeGenModule::GetAddrOfRTTI which... X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=31b7f52d8c8d459e80d2a72176cc7fcc4b7d8d38;p=clang Improve linkage of RTTI data structures. Introduce CodeGenModule::GetAddrOfRTTI which figures out the right linkage of the RTTI information for the given type and whether it should be defined or not. I will migrate clients over to GetAddrOfRTTI in subsequent commits (with tests). git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@91098 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp index 3548669058..ad8734d8da 100644 --- a/lib/CodeGen/CGExprCXX.cpp +++ b/lib/CodeGen/CGExprCXX.cpp @@ -352,18 +352,10 @@ void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) { llvm::Value * CodeGenFunction::EmitCXXTypeidExpr(const CXXTypeidExpr *E) { QualType Ty = E->getType(); const llvm::Type *LTy = ConvertType(Ty)->getPointerTo(); - if (E->isTypeOperand()) { - Ty = E->getTypeOperand(); - CanQualType CanTy = CGM.getContext().getCanonicalType(Ty); - Ty = CanTy.getUnqualifiedType().getNonReferenceType(); - if (const RecordType *RT = Ty->getAs()) { - const CXXRecordDecl *RD = cast(RT->getDecl()); - if (RD->isPolymorphic()) - return Builder.CreateBitCast(CGM.GenerateRTTIRef(RD), LTy); - return Builder.CreateBitCast(CGM.GenerateRTTI(RD), LTy); - } - return Builder.CreateBitCast(CGM.GenerateRTTI(Ty), LTy); - } + + if (E->isTypeOperand()) + return Builder.CreateBitCast(CGM.GetAddrOfRTTI(E->getTypeOperand()), LTy); + Expr *subE = E->getExprOperand(); Ty = subE->getType(); CanQualType CanTy = CGM.getContext().getCanonicalType(Ty); diff --git a/lib/CodeGen/CGRTTI.cpp b/lib/CodeGen/CGRTTI.cpp index 0e89e83c12..c8ce4ec6b9 100644 --- a/lib/CodeGen/CGRTTI.cpp +++ b/lib/CodeGen/CGRTTI.cpp @@ -68,27 +68,37 @@ public: return llvm::ConstantExpr::getBitCast(C, Int8PtrTy); } + // FIXME: This should be removed, and clients should pass in the linkage + // directly instead. + static inline llvm::GlobalVariable::LinkageTypes + GetLinkageFromExternFlag(bool Extern) { + if (Extern) + return llvm::GlobalValue::WeakODRLinkage; + + return llvm::GlobalValue::InternalLinkage; + } + + // FIXME: This should be removed, and clients should pass in the linkage + // directly instead. llvm::Constant *BuildName(QualType Ty, bool Hidden, bool Extern) { + return BuildName(Ty, Hidden, GetLinkageFromExternFlag(Extern)); + } + + llvm::Constant *BuildName(QualType Ty, bool Hidden, + llvm::GlobalVariable::LinkageTypes Linkage) { llvm::SmallString<256> OutName; CGM.getMangleContext().mangleCXXRTTIName(Ty, OutName); llvm::StringRef Name = OutName.str(); - llvm::GlobalVariable::LinkageTypes linktype; - linktype = llvm::GlobalValue::LinkOnceODRLinkage; - if (!Extern) - linktype = llvm::GlobalValue::InternalLinkage; - - llvm::GlobalVariable *GV; - GV = CGM.getModule().getGlobalVariable(Name); - if (GV && !GV->isDeclaration()) - return llvm::ConstantExpr::getBitCast(GV, Int8PtrTy); + llvm::GlobalVariable *OGV = CGM.getModule().getGlobalVariable(Name); + if (OGV && !OGV->isDeclaration()) + return llvm::ConstantExpr::getBitCast(OGV, Int8PtrTy); - llvm::Constant *C; - C = llvm::ConstantArray::get(VMContext, Name.substr(4)); + llvm::Constant *C = llvm::ConstantArray::get(VMContext, Name.substr(4)); - llvm::GlobalVariable *OGV = GV; - GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), true, linktype, - C, Name); + llvm::GlobalVariable *GV = + new llvm::GlobalVariable(CGM.getModule(), C->getType(), true, Linkage, + C, Name); if (OGV) { GV->takeName(OGV); llvm::Constant *NewPtr = llvm::ConstantExpr::getBitCast(GV, @@ -115,9 +125,6 @@ public: llvm::Constant *BuildTypeRef(QualType Ty) { llvm::Constant *C; - if (!CGM.getContext().getLangOptions().RTTI) - return llvm::Constant::getNullValue(Int8PtrTy); - llvm::SmallString<256> OutName; CGM.getMangleContext().mangleCXXRTTI(Ty, OutName); llvm::StringRef Name = OutName.str(); @@ -181,17 +188,14 @@ public: llvm::Constant *finish(std::vector &info, llvm::GlobalVariable *GV, - llvm::StringRef Name, bool Hidden, bool Extern) { - llvm::GlobalVariable::LinkageTypes linktype; - linktype = llvm::GlobalValue::LinkOnceODRLinkage; - if (!Extern) - linktype = llvm::GlobalValue::InternalLinkage; - - llvm::Constant *C; - C = llvm::ConstantStruct::get(VMContext, &info[0], info.size(), false); + llvm::StringRef Name, bool Hidden, + llvm::GlobalVariable::LinkageTypes Linkage) { + llvm::Constant *C = + llvm::ConstantStruct::get(VMContext, &info[0], info.size(), + /*Packed=*/false); llvm::GlobalVariable *OGV = GV; - GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), true, linktype, + GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), true, Linkage, C, Name); if (OGV) { GV->takeName(OGV); @@ -206,10 +210,9 @@ public: } - llvm::Constant *Buildclass_type_info(const CXXRecordDecl *RD) { - if (!CGM.getContext().getLangOptions().RTTI) - return llvm::Constant::getNullValue(Int8PtrTy); - + llvm::Constant * + Buildclass_type_info(const CXXRecordDecl *RD, + llvm::GlobalVariable::LinkageTypes Linkage) { llvm::Constant *C; llvm::SmallString<256> OutName; @@ -224,8 +227,11 @@ public: std::vector info; + // If we're in an anonymous namespace, then we always want internal linkage. + if (RD->isInAnonymousNamespace()) + Linkage = llvm::GlobalVariable::InternalLinkage; + bool Hidden = CGM.getDeclVisibilityMode(RD) == LangOptions::Hidden; - bool Extern = !RD->isInAnonymousNamespace(); bool simple = false; if (RD->getNumBases() == 0) @@ -237,7 +243,7 @@ public: C = BuildVtableRef("_ZTVN10__cxxabiv121__vmi_class_type_infoE"); info.push_back(C); info.push_back(BuildName(CGM.getContext().getTagDeclType(RD), Hidden, - Extern)); + Linkage)); // If we have no bases, there are no more fields. if (RD->getNumBases()) { @@ -273,7 +279,7 @@ public: } } - return finish(info, GV, Name, Hidden, Extern); + return finish(info, GV, Name, Hidden, Linkage); } /// - BuildFlags - Build a __flags value for __pbase_type_info. @@ -366,7 +372,8 @@ public: info.push_back(BuildType(QualType(PtrMemTy->getClass(), 0))); // We always generate these as hidden, only the name isn't hidden. - return finish(info, GV, Name, true, Extern); + return finish(info, GV, Name, /*Hidden=*/true, + GetLinkageFromExternFlag(Extern)); } llvm::Constant *BuildSimpleType(QualType Ty, const char *vtbl) { @@ -391,16 +398,18 @@ public: info.push_back(BuildName(Ty, Hidden, Extern)); // We always generate these as hidden, only the name isn't hidden. - return finish(info, GV, Name, true, Extern); + return finish(info, GV, Name, /*Hidden=*/true, + GetLinkageFromExternFlag(Extern)); } + /// BuildType - Builds the type info for the given type. llvm::Constant *BuildType(QualType Ty) { const clang::Type &Type = *CGM.getContext().getCanonicalType(Ty).getTypePtr(); if (const RecordType *RT = Ty.getTypePtr()->getAs()) if (const CXXRecordDecl *RD = cast(RT->getDecl())) - return Buildclass_type_info(RD); + return BuildClassTypeInfo(RD); switch (Type.getTypeClass()) { default: { @@ -438,9 +447,51 @@ public: return BuildSimpleType(Ty, "_ZTVN10__cxxabiv116__enum_type_infoE"); } } + + /// BuildClassTypeInfo - Builds the class type info (or a reference to it) + /// for the given record decl. + llvm::Constant *BuildClassTypeInfo(const CXXRecordDecl *RD) { + const CXXMethodDecl *KeyFunction = 0; + + if (RD->isDynamicClass()) + KeyFunction = CGM.getContext().getKeyFunction(RD); + + if (KeyFunction) { + // If the key function is defined in this translation unit, then the RTTI + // related constants should also be emitted here, with external linkage. + if (KeyFunction->getBody()) + return Buildclass_type_info(RD, llvm::GlobalValue::ExternalLinkage); + + // Otherwise, we just want a reference to the type info. + return Buildclass_type_infoRef(RD); + } + + // If there is no key function (or if the record doesn't have any virtual + // member functions or virtual bases), emit the type info with weak_odr + // linkage. + return Buildclass_type_info(RD, llvm::GlobalValue::WeakODRLinkage); + } }; } +llvm::Constant *CodeGenModule::GetAddrOfRTTI(const CXXRecordDecl *RD) { + if (!getContext().getLangOptions().RTTI) { + const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext); + return llvm::Constant::getNullValue(Int8PtrTy); + } + + return RTTIBuilder(*this).BuildClassTypeInfo(RD); +} + +llvm::Constant *CodeGenModule::GetAddrOfRTTI(QualType Ty) { + if (!getContext().getLangOptions().RTTI) { + const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext); + return llvm::Constant::getNullValue(Int8PtrTy); + } + + return RTTIBuilder(*this).BuildType(Ty); +} + llvm::Constant *CodeGenModule::GenerateRTTIRef(const CXXRecordDecl *RD) { RTTIBuilder b(*this); @@ -450,7 +501,7 @@ llvm::Constant *CodeGenModule::GenerateRTTIRef(const CXXRecordDecl *RD) { llvm::Constant *CodeGenModule::GenerateRTTI(const CXXRecordDecl *RD) { RTTIBuilder b(*this); - return b.Buildclass_type_info(RD); + return b.Buildclass_type_info(RD, llvm::GlobalValue::ExternalLinkage); } llvm::Constant *CodeGenModule::GenerateRTTI(QualType Ty) { diff --git a/lib/CodeGen/CGVtable.cpp b/lib/CodeGen/CGVtable.cpp index ef680d927d..752f69c7c2 100644 --- a/lib/CodeGen/CGVtable.cpp +++ b/lib/CodeGen/CGVtable.cpp @@ -203,7 +203,7 @@ public: LLVMPointerWidth(cgm.getContext().Target.getPointerWidth(0)) { Ptr8Ty = llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0); if (BuildVtable) - rtti = cgm.GenerateRTTIRef(MostDerivedClass); + rtti = CGM.GetAddrOfRTTI(MostDerivedClass); } // getVtableComponents - Returns a reference to the vtable components. @@ -1409,8 +1409,6 @@ void CGVtableInfo::GenerateClassData(llvm::GlobalVariable::LinkageTypes Linkage, } Vtable = GenerateVtable(Linkage, /*GenerateDefinition=*/true, RD, RD, 0); - - CGM.GenerateRTTI(RD); GenerateVTT(Linkage, RD); } diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h index 466aaa67cc..cc7ec9c301 100644 --- a/lib/CodeGen/CodeGenModule.h +++ b/lib/CodeGen/CodeGenModule.h @@ -212,6 +212,13 @@ public: llvm::Constant *GetAddrOfFunction(GlobalDecl GD, const llvm::Type *Ty = 0); + /// GetAddrOfRTTI - Get the address of the RTTI structure for the given type. + llvm::Constant *GetAddrOfRTTI(QualType Ty); + + /// GetAddrOfRTTI - Get the address of the RTTI structure for the given record + /// decl. + llvm::Constant *GetAddrOfRTTI(const CXXRecordDecl *RD); + /// GenerateRTTI - Generate the rtti information for the given type. llvm::Constant *GenerateRTTI(const CXXRecordDecl *RD); diff --git a/test/CodeGenCXX/rtti.cpp b/test/CodeGenCXX/rtti.cpp index a1ff1ff687..762c22ef9e 100644 --- a/test/CodeGenCXX/rtti.cpp +++ b/test/CodeGenCXX/rtti.cpp @@ -31,6 +31,11 @@ class test1_D : public test1_B7 { virtual void foo() { } } d1; +// CHECK:__ZTI7test1_D: +// CHECK-NEXT: .quad (__ZTVN10__cxxabiv120__si_class_type_infoE) + 16 +// CHECK-NEXT: .quad __ZTS7test1_D +// CHECK-NEXT: .quad __ZTI8test1_B7 + // CHECK: __ZTSPVi: // CHECK-NEXT: .asciz "PVi" @@ -77,13 +82,6 @@ class test1_D : public test1_B7 { // CHECK-NEXT: .quad __ZTIFvvE // CHECK-NEXT: .quad __ZTI7test3_A - - -// CHECK:__ZTI7test1_D: -// CHECK-NEXT: .quad (__ZTVN10__cxxabiv120__si_class_type_infoE) + 16 -// CHECK-NEXT: .quad __ZTS7test1_D -// CHECK-NEXT: .quad __ZTI8test1_B7 - // CHECK:__ZTI8test1_B7: // CHECK-NEXT: .quad (__ZTVN10__cxxabiv121__vmi_class_type_infoE) + 16 // CHECK-NEXT: .quad __ZTS8test1_B7 @@ -141,7 +139,6 @@ class test1_D : public test1_B7 { // CHECK-NEXT: .quad __ZTS8test1_B2 // CHECK-NEXT: .quad __ZTI8test1_B1 - class NP { }; void test2_1(); void test2_2(test1_D *dp) { @@ -166,7 +163,7 @@ void test2_2(test1_D *dp) { // CHECK-LL-NEXT: %2 = load %"class.std::type_info"** %1 // CHECK-LL-NEXT: %call = call zeroext i1 @_ZNKSt9type_infoeqERKS_(%"class.std::type_info"* %2, %"class.std::type_info"* bitcast (%{{[0-9]*}}* @_ZTI7test1_D to %"class.std::type_info"*)) -// CHECK-LL: %call2 = call zeroext i1 @_ZNKSt9type_infoeqERKS_(%"class.std::type_info"* bitcast (%0* @_ZTI2NP to %"class.std::type_info"*), %"class.std::type_info"* bitcast (%{{[0-9]*}}* @_ZTI7test1_D to %"class.std::type_info"*)) +// CHECK-LL: %call2 = call zeroext i1 @_ZNKSt9type_infoeqERKS_(%"class.std::type_info"* bitcast (%{{[0-9]*}}* @_ZTI2NP to %"class.std::type_info"*), %"class.std::type_info"* bitcast (%{{[0-9]*}}* @_ZTI7test1_D to %"class.std::type_info"*)) // CHECK-LL: %3 = bitcast %class.test1_B7* %tmp5 to %"class.std::type_info"*** // CHECK-LL-NEXT: %4 = icmp ne %"class.std::type_info"*** %3, null diff --git a/test/CodeGenCXX/virt-dtor-key.cpp b/test/CodeGenCXX/virt-dtor-key.cpp index 30f3563d8a..9cfd58dae2 100644 --- a/test/CodeGenCXX/virt-dtor-key.cpp +++ b/test/CodeGenCXX/virt-dtor-key.cpp @@ -1,5 +1,5 @@ // RUN: clang-cc -emit-llvm %s -o - | FileCheck %s -// CHECK: @_ZTI3foo = linkonce_odr constant +// CHECK: @_ZTI3foo = constant class foo { foo(); virtual ~foo(); diff --git a/test/CodeGenCXX/vtable-linkage.cpp b/test/CodeGenCXX/vtable-linkage.cpp index 81ac0e43b4..5bc509b65e 100644 --- a/test/CodeGenCXX/vtable-linkage.cpp +++ b/test/CodeGenCXX/vtable-linkage.cpp @@ -33,12 +33,18 @@ void D::f() { } // CHECK: @_ZTV1B = external constant // C has no key function, so its vtable should have weak_odr linkage. +// CHECK: @_ZTS1C = weak_odr constant +// CHECK: @_ZTI1C = weak_odr constant // CHECK: @_ZTV1C = weak_odr constant // D has a key function that is defined in this translation unit so its vtable is // defined in the translation unit. +// CHECK: @_ZTS1D = constant +// CHECK: @_ZTI1D = constant // CHECK: @_ZTV1D = constant // The A vtable should have internal linkage since it is inside an anonymous // namespace. +// CHECK: @_ZTSN12_GLOBAL__N_11AE = internal constant +// CHECK: @_ZTIN12_GLOBAL__N_11AE = internal constant // CHECK: @_ZTVN12_GLOBAL__N_11AE = internal constant