diff options
Diffstat (limited to 'clang/lib/CodeGen/CodeGenModule.cpp')
-rw-r--r-- | clang/lib/CodeGen/CodeGenModule.cpp | 58 |
1 files changed, 48 insertions, 10 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index d172b45..e088bd4 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -1958,16 +1958,7 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { if (NeedsGlobalCtor || NeedsGlobalDtor) EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor); - // If we are compiling with ASan, add metadata indicating dynamically - // initialized (and not blacklisted) globals. - if (SanOpts.Address && NeedsGlobalCtor && - !SanitizerBlacklist->isIn(*GV, "init")) { - llvm::NamedMDNode *DynamicInitializers = TheModule.getOrInsertNamedMetadata( - "llvm.asan.dynamically_initialized_globals"); - llvm::Value *GlobalToAdd[] = { GV }; - llvm::MDNode *ThisGlobal = llvm::MDNode::get(VMContext, GlobalToAdd); - DynamicInitializers->addOperand(ThisGlobal); - } + reportGlobalToASan(GV, D->getLocation(), NeedsGlobalCtor); // Emit global variable debug information. if (CGDebugInfo *DI = getModuleDebugInfo()) @@ -1975,6 +1966,51 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { DI->EmitGlobalVariable(GV, D); } +void CodeGenModule::reportGlobalToASan(llvm::GlobalVariable *GV, + SourceLocation Loc, bool IsDynInit) { + if (!SanOpts.Address) + return; + IsDynInit &= !SanitizerBlacklist->isIn(*GV, "init"); + bool IsBlacklisted = SanitizerBlacklist->isIn(*GV); + + llvm::LLVMContext &LLVMCtx = TheModule.getContext(); + + llvm::GlobalVariable *LocDescr = nullptr; + if (!IsBlacklisted) { + // Don't generate source location if a global is blacklisted - it won't + // be instrumented anyway. + PresumedLoc PLoc = Context.getSourceManager().getPresumedLoc(Loc); + if (PLoc.isValid()) { + llvm::Constant *LocData[] = { + GetAddrOfConstantCString(PLoc.getFilename()), + llvm::ConstantInt::get(llvm::Type::getInt32Ty(LLVMCtx), PLoc.getLine()), + llvm::ConstantInt::get(llvm::Type::getInt32Ty(LLVMCtx), + PLoc.getColumn()), + }; + auto LocStruct = llvm::ConstantStruct::getAnon(LocData); + LocDescr = new llvm::GlobalVariable(TheModule, LocStruct->getType(), true, + llvm::GlobalValue::PrivateLinkage, + LocStruct, ".asan_loc_descr"); + LocDescr->setUnnamedAddr(true); + // Add LocDescr to llvm.compiler.used, so that it won't be removed by + // the optimizer before the ASan instrumentation pass. + addCompilerUsedGlobal(LocDescr); + } + } + + llvm::Value *GlobalMetadata[] = { + GV, + LocDescr, + llvm::ConstantInt::get(llvm::Type::getInt1Ty(LLVMCtx), IsDynInit), + llvm::ConstantInt::get(llvm::Type::getInt1Ty(LLVMCtx), IsBlacklisted) + }; + + llvm::MDNode *ThisGlobal = llvm::MDNode::get(VMContext, GlobalMetadata); + llvm::NamedMDNode *AsanGlobals = + TheModule.getOrInsertNamedMetadata("llvm.asan.globals"); + AsanGlobals->addOperand(ThisGlobal); +} + static bool isVarDeclStrongDefinition(const VarDecl *D, bool NoCommon) { // Don't give variables common linkage if -fno-common was specified unless it // was overridden by a NoCommon attribute. @@ -2779,6 +2815,8 @@ CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) { auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); if (Entry) Entry->setValue(GV); + + reportGlobalToASan(GV, S->getStrTokenLoc(0)); return GV; } |