diff --git a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp index 85fda30499f..b774211a854 100644 --- a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp +++ b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp @@ -27,11 +27,14 @@ #include "llvm/ADT/StringExtras.h" #include "llvm/Intrinsics.h" #include "llvm/Function.h" +#include "llvm/LLVMContext.h" +#include "llvm/Metadata.h" #include "llvm/Module.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/IRBuilder.h" #include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetData.h" #include "llvm/Transforms/Instrumentation.h" #include "llvm/Transforms/Utils/ModuleUtils.h" @@ -61,6 +64,7 @@ struct ThreadSanitizer : public FunctionPass { static const size_t kNumberOfAccessSizes = 5; Value *TsanRead[kNumberOfAccessSizes]; Value *TsanWrite[kNumberOfAccessSizes]; + Value *TsanVptrUpdate; }; } // namespace @@ -105,6 +109,9 @@ bool ThreadSanitizer::doInitialization(Module &M) { TsanWrite[i] = M.getOrInsertFunction(WriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL); } + TsanVptrUpdate = M.getOrInsertFunction("__tsan_vptr_update", IRB.getVoidTy(), + IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), + NULL); return true; } @@ -151,10 +158,21 @@ bool ThreadSanitizer::runOnFunction(Function &F) { IRBuilder<> IRBRet(RetVec[i]); IRBRet.CreateCall(TsanFuncExit); } + Res = true; } return Res; } +static bool isVtableAccess(Instruction *I) { + if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa)) { + if (Tag->getNumOperands() < 1) return false; + if (MDString *Tag1 = dyn_cast(Tag->getOperand(0))) { + if (Tag1->getString() == "vtable pointer") return true; + } + } + return false; +} + bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I) { IRBuilder<> IRB(I); bool IsWrite = isa(*I); @@ -170,6 +188,13 @@ bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I) { // Ignore all unusual sizes. return false; } + if (IsWrite && isVtableAccess(I)) { + Value *StoredValue = cast(I)->getValueOperand(); + IRB.CreateCall2(TsanVptrUpdate, + IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()), + IRB.CreatePointerCast(StoredValue, IRB.getInt8PtrTy())); + return true; + } size_t Idx = CountTrailingZeros_32(TypeSize / 8); assert(Idx < kNumberOfAccessSizes); Value *OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx]; diff --git a/test/Instrumentation/ThreadSanitizer/lit.local.cfg b/test/Instrumentation/ThreadSanitizer/lit.local.cfg new file mode 100644 index 00000000000..19eebc0ac7a --- /dev/null +++ b/test/Instrumentation/ThreadSanitizer/lit.local.cfg @@ -0,0 +1 @@ +config.suffixes = ['.ll', '.c', '.cpp'] diff --git a/test/Instrumentation/ThreadSanitizer/vptr_update.ll b/test/Instrumentation/ThreadSanitizer/vptr_update.ll new file mode 100644 index 00000000000..f31865901b5 --- /dev/null +++ b/test/Instrumentation/ThreadSanitizer/vptr_update.ll @@ -0,0 +1,13 @@ +; RUN: opt < %s -tsan -S | FileCheck %s +; Check that vtable pointer updates are treated in a special way. +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" + +define void @Foo(i8** nocapture %a, i8* %b) nounwind uwtable { +entry: +; CHECK: call void @__tsan_vptr_update + store i8* %b, i8** %a, align 8, !tbaa !0 + ret void +} +!0 = metadata !{metadata !"vtable pointer", metadata !1} +!1 = metadata !{metadata !"Simple C/C++ TBAA", null} +