604 lines
24 KiB
C++
604 lines
24 KiB
C++
//===-- ThreadSanitizer.cpp - race detector -------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file is a part of ThreadSanitizer, a race detector.
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//
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// The tool is under development, for the details about previous versions see
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// http://code.google.com/p/data-race-test
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//
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// The instrumentation phase is quite simple:
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// - Insert calls to run-time library before every memory access.
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// - Optimizations may apply to avoid instrumenting some of the accesses.
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// - Insert calls at function entry/exit.
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// The rest is handled by the run-time library.
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//===----------------------------------------------------------------------===//
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#include "llvm/Transforms/Instrumentation.h"
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#include "llvm/ADT/SmallSet.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/Analysis/CaptureTracking.h"
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#include "llvm/Analysis/ValueTracking.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/Metadata.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/Type.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/Transforms/Utils/BasicBlockUtils.h"
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#include "llvm/Transforms/Utils/ModuleUtils.h"
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using namespace llvm;
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#define DEBUG_TYPE "tsan"
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static cl::opt<bool> ClInstrumentMemoryAccesses(
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"tsan-instrument-memory-accesses", cl::init(true),
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cl::desc("Instrument memory accesses"), cl::Hidden);
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static cl::opt<bool> ClInstrumentFuncEntryExit(
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"tsan-instrument-func-entry-exit", cl::init(true),
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cl::desc("Instrument function entry and exit"), cl::Hidden);
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static cl::opt<bool> ClInstrumentAtomics(
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"tsan-instrument-atomics", cl::init(true),
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cl::desc("Instrument atomics"), cl::Hidden);
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static cl::opt<bool> ClInstrumentMemIntrinsics(
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"tsan-instrument-memintrinsics", cl::init(true),
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cl::desc("Instrument memintrinsics (memset/memcpy/memmove)"), cl::Hidden);
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STATISTIC(NumInstrumentedReads, "Number of instrumented reads");
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STATISTIC(NumInstrumentedWrites, "Number of instrumented writes");
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STATISTIC(NumOmittedReadsBeforeWrite,
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"Number of reads ignored due to following writes");
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STATISTIC(NumAccessesWithBadSize, "Number of accesses with bad size");
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STATISTIC(NumInstrumentedVtableWrites, "Number of vtable ptr writes");
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STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads");
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STATISTIC(NumOmittedReadsFromConstantGlobals,
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"Number of reads from constant globals");
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STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads");
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STATISTIC(NumOmittedNonCaptured, "Number of accesses ignored due to capturing");
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static const char *const kTsanModuleCtorName = "tsan.module_ctor";
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static const char *const kTsanInitName = "__tsan_init";
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namespace {
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/// ThreadSanitizer: instrument the code in module to find races.
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struct ThreadSanitizer : public FunctionPass {
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ThreadSanitizer() : FunctionPass(ID) {}
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const char *getPassName() const override;
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bool runOnFunction(Function &F) override;
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bool doInitialization(Module &M) override;
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static char ID; // Pass identification, replacement for typeid.
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private:
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void initializeCallbacks(Module &M);
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bool instrumentLoadOrStore(Instruction *I, const DataLayout &DL);
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bool instrumentAtomic(Instruction *I, const DataLayout &DL);
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bool instrumentMemIntrinsic(Instruction *I);
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void chooseInstructionsToInstrument(SmallVectorImpl<Instruction *> &Local,
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SmallVectorImpl<Instruction *> &All,
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const DataLayout &DL);
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bool addrPointsToConstantData(Value *Addr);
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int getMemoryAccessFuncIndex(Value *Addr, const DataLayout &DL);
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Type *IntptrTy;
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IntegerType *OrdTy;
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// Callbacks to run-time library are computed in doInitialization.
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Function *TsanFuncEntry;
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Function *TsanFuncExit;
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// Accesses sizes are powers of two: 1, 2, 4, 8, 16.
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static const size_t kNumberOfAccessSizes = 5;
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Function *TsanRead[kNumberOfAccessSizes];
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Function *TsanWrite[kNumberOfAccessSizes];
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Function *TsanUnalignedRead[kNumberOfAccessSizes];
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Function *TsanUnalignedWrite[kNumberOfAccessSizes];
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Function *TsanAtomicLoad[kNumberOfAccessSizes];
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Function *TsanAtomicStore[kNumberOfAccessSizes];
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Function *TsanAtomicRMW[AtomicRMWInst::LAST_BINOP + 1][kNumberOfAccessSizes];
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Function *TsanAtomicCAS[kNumberOfAccessSizes];
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Function *TsanAtomicThreadFence;
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Function *TsanAtomicSignalFence;
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Function *TsanVptrUpdate;
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Function *TsanVptrLoad;
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Function *MemmoveFn, *MemcpyFn, *MemsetFn;
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Function *TsanCtorFunction;
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};
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} // namespace
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char ThreadSanitizer::ID = 0;
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INITIALIZE_PASS(ThreadSanitizer, "tsan",
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"ThreadSanitizer: detects data races.",
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false, false)
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const char *ThreadSanitizer::getPassName() const {
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return "ThreadSanitizer";
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}
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FunctionPass *llvm::createThreadSanitizerPass() {
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return new ThreadSanitizer();
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}
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void ThreadSanitizer::initializeCallbacks(Module &M) {
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IRBuilder<> IRB(M.getContext());
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// Initialize the callbacks.
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TsanFuncEntry = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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"__tsan_func_entry", IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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TsanFuncExit = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction("__tsan_func_exit", IRB.getVoidTy(), nullptr));
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OrdTy = IRB.getInt32Ty();
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for (size_t i = 0; i < kNumberOfAccessSizes; ++i) {
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const size_t ByteSize = 1 << i;
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const size_t BitSize = ByteSize * 8;
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SmallString<32> ReadName("__tsan_read" + itostr(ByteSize));
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TsanRead[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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ReadName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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SmallString<32> WriteName("__tsan_write" + itostr(ByteSize));
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TsanWrite[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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WriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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SmallString<64> UnalignedReadName("__tsan_unaligned_read" +
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itostr(ByteSize));
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TsanUnalignedRead[i] =
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checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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UnalignedReadName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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SmallString<64> UnalignedWriteName("__tsan_unaligned_write" +
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itostr(ByteSize));
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TsanUnalignedWrite[i] =
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checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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UnalignedWriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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Type *Ty = Type::getIntNTy(M.getContext(), BitSize);
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Type *PtrTy = Ty->getPointerTo();
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SmallString<32> AtomicLoadName("__tsan_atomic" + itostr(BitSize) +
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"_load");
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TsanAtomicLoad[i] = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction(AtomicLoadName, Ty, PtrTy, OrdTy, nullptr));
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SmallString<32> AtomicStoreName("__tsan_atomic" + itostr(BitSize) +
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"_store");
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TsanAtomicStore[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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AtomicStoreName, IRB.getVoidTy(), PtrTy, Ty, OrdTy, nullptr));
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for (int op = AtomicRMWInst::FIRST_BINOP;
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op <= AtomicRMWInst::LAST_BINOP; ++op) {
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TsanAtomicRMW[op][i] = nullptr;
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const char *NamePart = nullptr;
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if (op == AtomicRMWInst::Xchg)
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NamePart = "_exchange";
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else if (op == AtomicRMWInst::Add)
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NamePart = "_fetch_add";
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else if (op == AtomicRMWInst::Sub)
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NamePart = "_fetch_sub";
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else if (op == AtomicRMWInst::And)
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NamePart = "_fetch_and";
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else if (op == AtomicRMWInst::Or)
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NamePart = "_fetch_or";
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else if (op == AtomicRMWInst::Xor)
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NamePart = "_fetch_xor";
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else if (op == AtomicRMWInst::Nand)
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NamePart = "_fetch_nand";
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else
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continue;
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SmallString<32> RMWName("__tsan_atomic" + itostr(BitSize) + NamePart);
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TsanAtomicRMW[op][i] = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction(RMWName, Ty, PtrTy, Ty, OrdTy, nullptr));
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}
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SmallString<32> AtomicCASName("__tsan_atomic" + itostr(BitSize) +
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"_compare_exchange_val");
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TsanAtomicCAS[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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AtomicCASName, Ty, PtrTy, Ty, Ty, OrdTy, OrdTy, nullptr));
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}
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TsanVptrUpdate = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction("__tsan_vptr_update", IRB.getVoidTy(),
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IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), nullptr));
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TsanVptrLoad = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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"__tsan_vptr_read", IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
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TsanAtomicThreadFence = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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"__tsan_atomic_thread_fence", IRB.getVoidTy(), OrdTy, nullptr));
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TsanAtomicSignalFence = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
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"__tsan_atomic_signal_fence", IRB.getVoidTy(), OrdTy, nullptr));
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MemmoveFn = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction("memmove", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
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IRB.getInt8PtrTy(), IntptrTy, nullptr));
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MemcpyFn = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction("memcpy", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
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IRB.getInt8PtrTy(), IntptrTy, nullptr));
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MemsetFn = checkSanitizerInterfaceFunction(
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M.getOrInsertFunction("memset", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
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IRB.getInt32Ty(), IntptrTy, nullptr));
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}
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bool ThreadSanitizer::doInitialization(Module &M) {
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const DataLayout &DL = M.getDataLayout();
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IntptrTy = DL.getIntPtrType(M.getContext());
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std::tie(TsanCtorFunction, std::ignore) = createSanitizerCtorAndInitFunctions(
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M, kTsanModuleCtorName, kTsanInitName, /*InitArgTypes=*/{},
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/*InitArgs=*/{});
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appendToGlobalCtors(M, TsanCtorFunction, 0);
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return true;
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}
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static bool isVtableAccess(Instruction *I) {
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if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa))
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return Tag->isTBAAVtableAccess();
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return false;
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}
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bool ThreadSanitizer::addrPointsToConstantData(Value *Addr) {
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// If this is a GEP, just analyze its pointer operand.
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if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Addr))
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Addr = GEP->getPointerOperand();
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if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Addr)) {
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if (GV->isConstant()) {
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// Reads from constant globals can not race with any writes.
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NumOmittedReadsFromConstantGlobals++;
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return true;
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}
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} else if (LoadInst *L = dyn_cast<LoadInst>(Addr)) {
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if (isVtableAccess(L)) {
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// Reads from a vtable pointer can not race with any writes.
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NumOmittedReadsFromVtable++;
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return true;
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}
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}
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return false;
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}
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// Instrumenting some of the accesses may be proven redundant.
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// Currently handled:
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// - read-before-write (within same BB, no calls between)
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// - not captured variables
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//
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// We do not handle some of the patterns that should not survive
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// after the classic compiler optimizations.
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// E.g. two reads from the same temp should be eliminated by CSE,
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// two writes should be eliminated by DSE, etc.
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//
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// 'Local' is a vector of insns within the same BB (no calls between).
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// 'All' is a vector of insns that will be instrumented.
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void ThreadSanitizer::chooseInstructionsToInstrument(
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SmallVectorImpl<Instruction *> &Local, SmallVectorImpl<Instruction *> &All,
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const DataLayout &DL) {
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SmallSet<Value*, 8> WriteTargets;
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// Iterate from the end.
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for (SmallVectorImpl<Instruction*>::reverse_iterator It = Local.rbegin(),
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E = Local.rend(); It != E; ++It) {
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Instruction *I = *It;
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if (StoreInst *Store = dyn_cast<StoreInst>(I)) {
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WriteTargets.insert(Store->getPointerOperand());
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} else {
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LoadInst *Load = cast<LoadInst>(I);
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Value *Addr = Load->getPointerOperand();
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if (WriteTargets.count(Addr)) {
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// We will write to this temp, so no reason to analyze the read.
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NumOmittedReadsBeforeWrite++;
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continue;
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}
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if (addrPointsToConstantData(Addr)) {
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// Addr points to some constant data -- it can not race with any writes.
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continue;
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}
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}
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Value *Addr = isa<StoreInst>(*I)
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? cast<StoreInst>(I)->getPointerOperand()
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: cast<LoadInst>(I)->getPointerOperand();
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if (isa<AllocaInst>(GetUnderlyingObject(Addr, DL)) &&
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!PointerMayBeCaptured(Addr, true, true)) {
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// The variable is addressable but not captured, so it cannot be
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// referenced from a different thread and participate in a data race
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// (see llvm/Analysis/CaptureTracking.h for details).
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NumOmittedNonCaptured++;
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continue;
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}
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All.push_back(I);
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}
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Local.clear();
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}
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static bool isAtomic(Instruction *I) {
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if (LoadInst *LI = dyn_cast<LoadInst>(I))
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return LI->isAtomic() && LI->getSynchScope() == CrossThread;
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if (StoreInst *SI = dyn_cast<StoreInst>(I))
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return SI->isAtomic() && SI->getSynchScope() == CrossThread;
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if (isa<AtomicRMWInst>(I))
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return true;
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if (isa<AtomicCmpXchgInst>(I))
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return true;
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if (isa<FenceInst>(I))
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return true;
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return false;
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}
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bool ThreadSanitizer::runOnFunction(Function &F) {
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// This is required to prevent instrumenting call to __tsan_init from within
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// the module constructor.
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if (&F == TsanCtorFunction)
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return false;
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initializeCallbacks(*F.getParent());
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SmallVector<Instruction*, 8> RetVec;
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SmallVector<Instruction*, 8> AllLoadsAndStores;
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SmallVector<Instruction*, 8> LocalLoadsAndStores;
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SmallVector<Instruction*, 8> AtomicAccesses;
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SmallVector<Instruction*, 8> MemIntrinCalls;
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bool Res = false;
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bool HasCalls = false;
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bool SanitizeFunction = F.hasFnAttribute(Attribute::SanitizeThread);
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const DataLayout &DL = F.getParent()->getDataLayout();
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// Traverse all instructions, collect loads/stores/returns, check for calls.
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for (auto &BB : F) {
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for (auto &Inst : BB) {
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if (isAtomic(&Inst))
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AtomicAccesses.push_back(&Inst);
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else if (isa<LoadInst>(Inst) || isa<StoreInst>(Inst))
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LocalLoadsAndStores.push_back(&Inst);
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else if (isa<ReturnInst>(Inst))
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RetVec.push_back(&Inst);
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else if (isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) {
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if (isa<MemIntrinsic>(Inst))
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MemIntrinCalls.push_back(&Inst);
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HasCalls = true;
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chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores,
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DL);
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}
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}
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chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores, DL);
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}
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// We have collected all loads and stores.
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// FIXME: many of these accesses do not need to be checked for races
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// (e.g. variables that do not escape, etc).
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// Instrument memory accesses only if we want to report bugs in the function.
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if (ClInstrumentMemoryAccesses && SanitizeFunction)
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for (auto Inst : AllLoadsAndStores) {
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Res |= instrumentLoadOrStore(Inst, DL);
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}
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// Instrument atomic memory accesses in any case (they can be used to
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// implement synchronization).
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if (ClInstrumentAtomics)
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for (auto Inst : AtomicAccesses) {
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Res |= instrumentAtomic(Inst, DL);
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}
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if (ClInstrumentMemIntrinsics && SanitizeFunction)
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for (auto Inst : MemIntrinCalls) {
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Res |= instrumentMemIntrinsic(Inst);
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}
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// Instrument function entry/exit points if there were instrumented accesses.
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if ((Res || HasCalls) && ClInstrumentFuncEntryExit) {
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IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI());
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Value *ReturnAddress = IRB.CreateCall(
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Intrinsic::getDeclaration(F.getParent(), Intrinsic::returnaddress),
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IRB.getInt32(0));
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IRB.CreateCall(TsanFuncEntry, ReturnAddress);
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for (auto RetInst : RetVec) {
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IRBuilder<> IRBRet(RetInst);
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IRBRet.CreateCall(TsanFuncExit, {});
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}
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Res = true;
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}
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return Res;
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}
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bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I,
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const DataLayout &DL) {
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IRBuilder<> IRB(I);
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bool IsWrite = isa<StoreInst>(*I);
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Value *Addr = IsWrite
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? cast<StoreInst>(I)->getPointerOperand()
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: cast<LoadInst>(I)->getPointerOperand();
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int Idx = getMemoryAccessFuncIndex(Addr, DL);
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if (Idx < 0)
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return false;
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if (IsWrite && isVtableAccess(I)) {
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DEBUG(dbgs() << " VPTR : " << *I << "\n");
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Value *StoredValue = cast<StoreInst>(I)->getValueOperand();
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// StoredValue may be a vector type if we are storing several vptrs at once.
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// In this case, just take the first element of the vector since this is
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// enough to find vptr races.
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if (isa<VectorType>(StoredValue->getType()))
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StoredValue = IRB.CreateExtractElement(
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StoredValue, ConstantInt::get(IRB.getInt32Ty(), 0));
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if (StoredValue->getType()->isIntegerTy())
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StoredValue = IRB.CreateIntToPtr(StoredValue, IRB.getInt8PtrTy());
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// Call TsanVptrUpdate.
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IRB.CreateCall(TsanVptrUpdate,
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{IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()),
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IRB.CreatePointerCast(StoredValue, IRB.getInt8PtrTy())});
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NumInstrumentedVtableWrites++;
|
|
return true;
|
|
}
|
|
if (!IsWrite && isVtableAccess(I)) {
|
|
IRB.CreateCall(TsanVptrLoad,
|
|
IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
|
|
NumInstrumentedVtableReads++;
|
|
return true;
|
|
}
|
|
const unsigned Alignment = IsWrite
|
|
? cast<StoreInst>(I)->getAlignment()
|
|
: cast<LoadInst>(I)->getAlignment();
|
|
Type *OrigTy = cast<PointerType>(Addr->getType())->getElementType();
|
|
const uint32_t TypeSize = DL.getTypeStoreSizeInBits(OrigTy);
|
|
Value *OnAccessFunc = nullptr;
|
|
if (Alignment == 0 || Alignment >= 8 || (Alignment % (TypeSize / 8)) == 0)
|
|
OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx];
|
|
else
|
|
OnAccessFunc = IsWrite ? TsanUnalignedWrite[Idx] : TsanUnalignedRead[Idx];
|
|
IRB.CreateCall(OnAccessFunc, IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
|
|
if (IsWrite) NumInstrumentedWrites++;
|
|
else NumInstrumentedReads++;
|
|
return true;
|
|
}
|
|
|
|
static ConstantInt *createOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
|
|
uint32_t v = 0;
|
|
switch (ord) {
|
|
case NotAtomic: llvm_unreachable("unexpected atomic ordering!");
|
|
case Unordered: // Fall-through.
|
|
case Monotonic: v = 0; break;
|
|
// case Consume: v = 1; break; // Not specified yet.
|
|
case Acquire: v = 2; break;
|
|
case Release: v = 3; break;
|
|
case AcquireRelease: v = 4; break;
|
|
case SequentiallyConsistent: v = 5; break;
|
|
}
|
|
return IRB->getInt32(v);
|
|
}
|
|
|
|
// If a memset intrinsic gets inlined by the code gen, we will miss races on it.
|
|
// So, we either need to ensure the intrinsic is not inlined, or instrument it.
|
|
// We do not instrument memset/memmove/memcpy intrinsics (too complicated),
|
|
// instead we simply replace them with regular function calls, which are then
|
|
// intercepted by the run-time.
|
|
// Since tsan is running after everyone else, the calls should not be
|
|
// replaced back with intrinsics. If that becomes wrong at some point,
|
|
// we will need to call e.g. __tsan_memset to avoid the intrinsics.
|
|
bool ThreadSanitizer::instrumentMemIntrinsic(Instruction *I) {
|
|
IRBuilder<> IRB(I);
|
|
if (MemSetInst *M = dyn_cast<MemSetInst>(I)) {
|
|
IRB.CreateCall(
|
|
MemsetFn,
|
|
{IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
|
|
IRB.CreateIntCast(M->getArgOperand(1), IRB.getInt32Ty(), false),
|
|
IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false)});
|
|
I->eraseFromParent();
|
|
} else if (MemTransferInst *M = dyn_cast<MemTransferInst>(I)) {
|
|
IRB.CreateCall(
|
|
isa<MemCpyInst>(M) ? MemcpyFn : MemmoveFn,
|
|
{IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
|
|
IRB.CreatePointerCast(M->getArgOperand(1), IRB.getInt8PtrTy()),
|
|
IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false)});
|
|
I->eraseFromParent();
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x
|
|
// standards. For background see C++11 standard. A slightly older, publicly
|
|
// available draft of the standard (not entirely up-to-date, but close enough
|
|
// for casual browsing) is available here:
|
|
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
|
|
// The following page contains more background information:
|
|
// http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/
|
|
|
|
bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
|
|
IRBuilder<> IRB(I);
|
|
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
|
|
Value *Addr = LI->getPointerOperand();
|
|
int Idx = getMemoryAccessFuncIndex(Addr, DL);
|
|
if (Idx < 0)
|
|
return false;
|
|
const size_t ByteSize = 1 << Idx;
|
|
const size_t BitSize = ByteSize * 8;
|
|
Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
|
|
Type *PtrTy = Ty->getPointerTo();
|
|
Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
|
|
createOrdering(&IRB, LI->getOrdering())};
|
|
CallInst *C = CallInst::Create(TsanAtomicLoad[Idx], Args);
|
|
ReplaceInstWithInst(I, C);
|
|
|
|
} else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
|
|
Value *Addr = SI->getPointerOperand();
|
|
int Idx = getMemoryAccessFuncIndex(Addr, DL);
|
|
if (Idx < 0)
|
|
return false;
|
|
const size_t ByteSize = 1 << Idx;
|
|
const size_t BitSize = ByteSize * 8;
|
|
Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
|
|
Type *PtrTy = Ty->getPointerTo();
|
|
Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
|
|
IRB.CreateIntCast(SI->getValueOperand(), Ty, false),
|
|
createOrdering(&IRB, SI->getOrdering())};
|
|
CallInst *C = CallInst::Create(TsanAtomicStore[Idx], Args);
|
|
ReplaceInstWithInst(I, C);
|
|
} else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I)) {
|
|
Value *Addr = RMWI->getPointerOperand();
|
|
int Idx = getMemoryAccessFuncIndex(Addr, DL);
|
|
if (Idx < 0)
|
|
return false;
|
|
Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx];
|
|
if (!F)
|
|
return false;
|
|
const size_t ByteSize = 1 << Idx;
|
|
const size_t BitSize = ByteSize * 8;
|
|
Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
|
|
Type *PtrTy = Ty->getPointerTo();
|
|
Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
|
|
IRB.CreateIntCast(RMWI->getValOperand(), Ty, false),
|
|
createOrdering(&IRB, RMWI->getOrdering())};
|
|
CallInst *C = CallInst::Create(F, Args);
|
|
ReplaceInstWithInst(I, C);
|
|
} else if (AtomicCmpXchgInst *CASI = dyn_cast<AtomicCmpXchgInst>(I)) {
|
|
Value *Addr = CASI->getPointerOperand();
|
|
int Idx = getMemoryAccessFuncIndex(Addr, DL);
|
|
if (Idx < 0)
|
|
return false;
|
|
const size_t ByteSize = 1 << Idx;
|
|
const size_t BitSize = ByteSize * 8;
|
|
Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
|
|
Type *PtrTy = Ty->getPointerTo();
|
|
Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
|
|
IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false),
|
|
IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false),
|
|
createOrdering(&IRB, CASI->getSuccessOrdering()),
|
|
createOrdering(&IRB, CASI->getFailureOrdering())};
|
|
CallInst *C = IRB.CreateCall(TsanAtomicCAS[Idx], Args);
|
|
Value *Success = IRB.CreateICmpEQ(C, CASI->getCompareOperand());
|
|
|
|
Value *Res = IRB.CreateInsertValue(UndefValue::get(CASI->getType()), C, 0);
|
|
Res = IRB.CreateInsertValue(Res, Success, 1);
|
|
|
|
I->replaceAllUsesWith(Res);
|
|
I->eraseFromParent();
|
|
} else if (FenceInst *FI = dyn_cast<FenceInst>(I)) {
|
|
Value *Args[] = {createOrdering(&IRB, FI->getOrdering())};
|
|
Function *F = FI->getSynchScope() == SingleThread ?
|
|
TsanAtomicSignalFence : TsanAtomicThreadFence;
|
|
CallInst *C = CallInst::Create(F, Args);
|
|
ReplaceInstWithInst(I, C);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
int ThreadSanitizer::getMemoryAccessFuncIndex(Value *Addr,
|
|
const DataLayout &DL) {
|
|
Type *OrigPtrTy = Addr->getType();
|
|
Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType();
|
|
assert(OrigTy->isSized());
|
|
uint32_t TypeSize = DL.getTypeStoreSizeInBits(OrigTy);
|
|
if (TypeSize != 8 && TypeSize != 16 &&
|
|
TypeSize != 32 && TypeSize != 64 && TypeSize != 128) {
|
|
NumAccessesWithBadSize++;
|
|
// Ignore all unusual sizes.
|
|
return -1;
|
|
}
|
|
size_t Idx = countTrailingZeros(TypeSize / 8);
|
|
assert(Idx < kNumberOfAccessSizes);
|
|
return Idx;
|
|
}
|