#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"
static const size_t kNumberOfAccessSizes = 5;
Value *TsanRead[kNumberOfAccessSizes];
Value *TsanWrite[kNumberOfAccessSizes];
+ Value *TsanVptrUpdate;
};
} // namespace
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;
}
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<MDString>(Tag->getOperand(0))) {
+ if (Tag1->getString() == "vtable pointer") return true;
+ }
+ }
+ return false;
+}
+
bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I) {
IRBuilder<> IRB(I);
bool IsWrite = isa<StoreInst>(*I);
// Ignore all unusual sizes.
return false;
}
+ if (IsWrite && isVtableAccess(I)) {
+ Value *StoredValue = cast<StoreInst>(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];
--- /dev/null
+; 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}
+