--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libsanitizer/tsan/tsan_rtl.cpp	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,1117 @@
+//===-- tsan_rtl.cpp ------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+// Main file (entry points) for the TSan run-time.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_atomic.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_file.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
+#include "sanitizer_common/sanitizer_symbolizer.h"
+#include "tsan_defs.h"
+#include "tsan_platform.h"
+#include "tsan_rtl.h"
+#include "tsan_mman.h"
+#include "tsan_suppressions.h"
+#include "tsan_symbolize.h"
+#include "ubsan/ubsan_init.h"
+
+#ifdef __SSE3__
+// <emmintrin.h> transitively includes <stdlib.h>,
+// and it's prohibited to include std headers into tsan runtime.
+// So we do this dirty trick.
+#define _MM_MALLOC_H_INCLUDED
+#define __MM_MALLOC_H
+#include <emmintrin.h>
+typedef __m128i m128;
+#endif
+
+volatile int __tsan_resumed = 0;
+
+extern "C" void __tsan_resume() {
+  __tsan_resumed = 1;
+}
+
+namespace __tsan {
+
+#if !SANITIZER_GO && !SANITIZER_MAC
+__attribute__((tls_model("initial-exec")))
+THREADLOCAL char cur_thread_placeholder[sizeof(ThreadState)] ALIGNED(64);
+#endif
+static char ctx_placeholder[sizeof(Context)] ALIGNED(64);
+Context *ctx;
+
+// Can be overriden by a front-end.
+#ifdef TSAN_EXTERNAL_HOOKS
+bool OnFinalize(bool failed);
+void OnInitialize();
+#else
+SANITIZER_WEAK_CXX_DEFAULT_IMPL
+bool OnFinalize(bool failed) {
+  return failed;
+}
+SANITIZER_WEAK_CXX_DEFAULT_IMPL
+void OnInitialize() {}
+#endif
+
+static char thread_registry_placeholder[sizeof(ThreadRegistry)];
+
+static ThreadContextBase *CreateThreadContext(u32 tid) {
+  // Map thread trace when context is created.
+  char name[50];
+  internal_snprintf(name, sizeof(name), "trace %u", tid);
+  MapThreadTrace(GetThreadTrace(tid), TraceSize() * sizeof(Event), name);
+  const uptr hdr = GetThreadTraceHeader(tid);
+  internal_snprintf(name, sizeof(name), "trace header %u", tid);
+  MapThreadTrace(hdr, sizeof(Trace), name);
+  new((void*)hdr) Trace();
+  // We are going to use only a small part of the trace with the default
+  // value of history_size. However, the constructor writes to the whole trace.
+  // Unmap the unused part.
+  uptr hdr_end = hdr + sizeof(Trace);
+  hdr_end -= sizeof(TraceHeader) * (kTraceParts - TraceParts());
+  hdr_end = RoundUp(hdr_end, GetPageSizeCached());
+  if (hdr_end < hdr + sizeof(Trace))
+    UnmapOrDie((void*)hdr_end, hdr + sizeof(Trace) - hdr_end);
+  void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext));
+  return new(mem) ThreadContext(tid);
+}
+
+#if !SANITIZER_GO
+static const u32 kThreadQuarantineSize = 16;
+#else
+static const u32 kThreadQuarantineSize = 64;
+#endif
+
+Context::Context()
+  : initialized()
+  , report_mtx(MutexTypeReport, StatMtxReport)
+  , nreported()
+  , nmissed_expected()
+  , thread_registry(new(thread_registry_placeholder) ThreadRegistry(
+      CreateThreadContext, kMaxTid, kThreadQuarantineSize, kMaxTidReuse))
+  , racy_mtx(MutexTypeRacy, StatMtxRacy)
+  , racy_stacks()
+  , racy_addresses()
+  , fired_suppressions_mtx(MutexTypeFired, StatMtxFired)
+  , clock_alloc("clock allocator") {
+  fired_suppressions.reserve(8);
+}
+
+// The objects are allocated in TLS, so one may rely on zero-initialization.
+ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
+                         unsigned reuse_count,
+                         uptr stk_addr, uptr stk_size,
+                         uptr tls_addr, uptr tls_size)
+  : fast_state(tid, epoch)
+  // Do not touch these, rely on zero initialization,
+  // they may be accessed before the ctor.
+  // , ignore_reads_and_writes()
+  // , ignore_interceptors()
+  , clock(tid, reuse_count)
+#if !SANITIZER_GO
+  , jmp_bufs()
+#endif
+  , tid(tid)
+  , unique_id(unique_id)
+  , stk_addr(stk_addr)
+  , stk_size(stk_size)
+  , tls_addr(tls_addr)
+  , tls_size(tls_size)
+#if !SANITIZER_GO
+  , last_sleep_clock(tid)
+#endif
+{
+}
+
+#if !SANITIZER_GO
+static void MemoryProfiler(Context *ctx, fd_t fd, int i) {
+  uptr n_threads;
+  uptr n_running_threads;
+  ctx->thread_registry->GetNumberOfThreads(&n_threads, &n_running_threads);
+  InternalMmapVector<char> buf(4096);
+  WriteMemoryProfile(buf.data(), buf.size(), n_threads, n_running_threads);
+  WriteToFile(fd, buf.data(), internal_strlen(buf.data()));
+}
+
+static void BackgroundThread(void *arg) {
+  // This is a non-initialized non-user thread, nothing to see here.
+  // We don't use ScopedIgnoreInterceptors, because we want ignores to be
+  // enabled even when the thread function exits (e.g. during pthread thread
+  // shutdown code).
+  cur_thread_init();
+  cur_thread()->ignore_interceptors++;
+  const u64 kMs2Ns = 1000 * 1000;
+
+  fd_t mprof_fd = kInvalidFd;
+  if (flags()->profile_memory && flags()->profile_memory[0]) {
+    if (internal_strcmp(flags()->profile_memory, "stdout") == 0) {
+      mprof_fd = 1;
+    } else if (internal_strcmp(flags()->profile_memory, "stderr") == 0) {
+      mprof_fd = 2;
+    } else {
+      InternalScopedString filename(kMaxPathLength);
+      filename.append("%s.%d", flags()->profile_memory, (int)internal_getpid());
+      fd_t fd = OpenFile(filename.data(), WrOnly);
+      if (fd == kInvalidFd) {
+        Printf("ThreadSanitizer: failed to open memory profile file '%s'\n",
+            &filename[0]);
+      } else {
+        mprof_fd = fd;
+      }
+    }
+  }
+
+  u64 last_flush = NanoTime();
+  uptr last_rss = 0;
+  for (int i = 0;
+      atomic_load(&ctx->stop_background_thread, memory_order_relaxed) == 0;
+      i++) {
+    SleepForMillis(100);
+    u64 now = NanoTime();
+
+    // Flush memory if requested.
+    if (flags()->flush_memory_ms > 0) {
+      if (last_flush + flags()->flush_memory_ms * kMs2Ns < now) {
+        VPrintf(1, "ThreadSanitizer: periodic memory flush\n");
+        FlushShadowMemory();
+        last_flush = NanoTime();
+      }
+    }
+    // GetRSS can be expensive on huge programs, so don't do it every 100ms.
+    if (flags()->memory_limit_mb > 0) {
+      uptr rss = GetRSS();
+      uptr limit = uptr(flags()->memory_limit_mb) << 20;
+      VPrintf(1, "ThreadSanitizer: memory flush check"
+                 " RSS=%llu LAST=%llu LIMIT=%llu\n",
+              (u64)rss >> 20, (u64)last_rss >> 20, (u64)limit >> 20);
+      if (2 * rss > limit + last_rss) {
+        VPrintf(1, "ThreadSanitizer: flushing memory due to RSS\n");
+        FlushShadowMemory();
+        rss = GetRSS();
+        VPrintf(1, "ThreadSanitizer: memory flushed RSS=%llu\n", (u64)rss>>20);
+      }
+      last_rss = rss;
+    }
+
+    // Write memory profile if requested.
+    if (mprof_fd != kInvalidFd)
+      MemoryProfiler(ctx, mprof_fd, i);
+
+    // Flush symbolizer cache if requested.
+    if (flags()->flush_symbolizer_ms > 0) {
+      u64 last = atomic_load(&ctx->last_symbolize_time_ns,
+                             memory_order_relaxed);
+      if (last != 0 && last + flags()->flush_symbolizer_ms * kMs2Ns < now) {
+        Lock l(&ctx->report_mtx);
+        ScopedErrorReportLock l2;
+        SymbolizeFlush();
+        atomic_store(&ctx->last_symbolize_time_ns, 0, memory_order_relaxed);
+      }
+    }
+  }
+}
+
+static void StartBackgroundThread() {
+  ctx->background_thread = internal_start_thread(&BackgroundThread, 0);
+}
+
+#ifndef __mips__
+static void StopBackgroundThread() {
+  atomic_store(&ctx->stop_background_thread, 1, memory_order_relaxed);
+  internal_join_thread(ctx->background_thread);
+  ctx->background_thread = 0;
+}
+#endif
+#endif
+
+void DontNeedShadowFor(uptr addr, uptr size) {
+  ReleaseMemoryPagesToOS(MemToShadow(addr), MemToShadow(addr + size));
+}
+
+#if !SANITIZER_GO
+void UnmapShadow(ThreadState *thr, uptr addr, uptr size) {
+  if (size == 0) return;
+  DontNeedShadowFor(addr, size);
+  ScopedGlobalProcessor sgp;
+  ctx->metamap.ResetRange(thr->proc(), addr, size);
+}
+#endif
+
+void MapShadow(uptr addr, uptr size) {
+  // Global data is not 64K aligned, but there are no adjacent mappings,
+  // so we can get away with unaligned mapping.
+  // CHECK_EQ(addr, addr & ~((64 << 10) - 1));  // windows wants 64K alignment
+  const uptr kPageSize = GetPageSizeCached();
+  uptr shadow_begin = RoundDownTo((uptr)MemToShadow(addr), kPageSize);
+  uptr shadow_end = RoundUpTo((uptr)MemToShadow(addr + size), kPageSize);
+  if (!MmapFixedNoReserve(shadow_begin, shadow_end - shadow_begin, "shadow"))
+    Die();
+
+  // Meta shadow is 2:1, so tread carefully.
+  static bool data_mapped = false;
+  static uptr mapped_meta_end = 0;
+  uptr meta_begin = (uptr)MemToMeta(addr);
+  uptr meta_end = (uptr)MemToMeta(addr + size);
+  meta_begin = RoundDownTo(meta_begin, 64 << 10);
+  meta_end = RoundUpTo(meta_end, 64 << 10);
+  if (!data_mapped) {
+    // First call maps data+bss.
+    data_mapped = true;
+    if (!MmapFixedNoReserve(meta_begin, meta_end - meta_begin, "meta shadow"))
+      Die();
+  } else {
+    // Mapping continous heap.
+    // Windows wants 64K alignment.
+    meta_begin = RoundDownTo(meta_begin, 64 << 10);
+    meta_end = RoundUpTo(meta_end, 64 << 10);
+    if (meta_end <= mapped_meta_end)
+      return;
+    if (meta_begin < mapped_meta_end)
+      meta_begin = mapped_meta_end;
+    if (!MmapFixedNoReserve(meta_begin, meta_end - meta_begin, "meta shadow"))
+      Die();
+    mapped_meta_end = meta_end;
+  }
+  VPrintf(2, "mapped meta shadow for (%p-%p) at (%p-%p)\n",
+      addr, addr+size, meta_begin, meta_end);
+}
+
+void MapThreadTrace(uptr addr, uptr size, const char *name) {
+  DPrintf("#0: Mapping trace at %p-%p(0x%zx)\n", addr, addr + size, size);
+  CHECK_GE(addr, TraceMemBeg());
+  CHECK_LE(addr + size, TraceMemEnd());
+  CHECK_EQ(addr, addr & ~((64 << 10) - 1));  // windows wants 64K alignment
+  if (!MmapFixedNoReserve(addr, size, name)) {
+    Printf("FATAL: ThreadSanitizer can not mmap thread trace (%p/%p)\n",
+        addr, size);
+    Die();
+  }
+}
+
+static void CheckShadowMapping() {
+  uptr beg, end;
+  for (int i = 0; GetUserRegion(i, &beg, &end); i++) {
+    // Skip cases for empty regions (heap definition for architectures that
+    // do not use 64-bit allocator).
+    if (beg == end)
+      continue;
+    VPrintf(3, "checking shadow region %p-%p\n", beg, end);
+    uptr prev = 0;
+    for (uptr p0 = beg; p0 <= end; p0 += (end - beg) / 4) {
+      for (int x = -(int)kShadowCell; x <= (int)kShadowCell; x += kShadowCell) {
+        const uptr p = RoundDown(p0 + x, kShadowCell);
+        if (p < beg || p >= end)
+          continue;
+        const uptr s = MemToShadow(p);
+        const uptr m = (uptr)MemToMeta(p);
+        VPrintf(3, "  checking pointer %p: shadow=%p meta=%p\n", p, s, m);
+        CHECK(IsAppMem(p));
+        CHECK(IsShadowMem(s));
+        CHECK_EQ(p, ShadowToMem(s));
+        CHECK(IsMetaMem(m));
+        if (prev) {
+          // Ensure that shadow and meta mappings are linear within a single
+          // user range. Lots of code that processes memory ranges assumes it.
+          const uptr prev_s = MemToShadow(prev);
+          const uptr prev_m = (uptr)MemToMeta(prev);
+          CHECK_EQ(s - prev_s, (p - prev) * kShadowMultiplier);
+          CHECK_EQ((m - prev_m) / kMetaShadowSize,
+                   (p - prev) / kMetaShadowCell);
+        }
+        prev = p;
+      }
+    }
+  }
+}
+
+#if !SANITIZER_GO
+static void OnStackUnwind(const SignalContext &sig, const void *,
+                          BufferedStackTrace *stack) {
+  stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
+                common_flags()->fast_unwind_on_fatal);
+}
+
+static void TsanOnDeadlySignal(int signo, void *siginfo, void *context) {
+  HandleDeadlySignal(siginfo, context, GetTid(), &OnStackUnwind, nullptr);
+}
+#endif
+
+void Initialize(ThreadState *thr) {
+  // Thread safe because done before all threads exist.
+  static bool is_initialized = false;
+  if (is_initialized)
+    return;
+  is_initialized = true;
+  // We are not ready to handle interceptors yet.
+  ScopedIgnoreInterceptors ignore;
+  SanitizerToolName = "ThreadSanitizer";
+  // Install tool-specific callbacks in sanitizer_common.
+  SetCheckFailedCallback(TsanCheckFailed);
+
+  ctx = new(ctx_placeholder) Context;
+  const char *env_name = SANITIZER_GO ? "GORACE" : "TSAN_OPTIONS";
+  const char *options = GetEnv(env_name);
+  CacheBinaryName();
+  CheckASLR();
+  InitializeFlags(&ctx->flags, options, env_name);
+  AvoidCVE_2016_2143();
+  __sanitizer::InitializePlatformEarly();
+  __tsan::InitializePlatformEarly();
+
+#if !SANITIZER_GO
+  // Re-exec ourselves if we need to set additional env or command line args.
+  MaybeReexec();
+
+  InitializeAllocator();
+  ReplaceSystemMalloc();
+#endif
+  if (common_flags()->detect_deadlocks)
+    ctx->dd = DDetector::Create(flags());
+  Processor *proc = ProcCreate();
+  ProcWire(proc, thr);
+  InitializeInterceptors();
+  CheckShadowMapping();
+  InitializePlatform();
+  InitializeMutex();
+  InitializeDynamicAnnotations();
+#if !SANITIZER_GO
+  InitializeShadowMemory();
+  InitializeAllocatorLate();
+  InstallDeadlySignalHandlers(TsanOnDeadlySignal);
+#endif
+  // Setup correct file descriptor for error reports.
+  __sanitizer_set_report_path(common_flags()->log_path);
+  InitializeSuppressions();
+#if !SANITIZER_GO
+  InitializeLibIgnore();
+  Symbolizer::GetOrInit()->AddHooks(EnterSymbolizer, ExitSymbolizer);
+#endif
+
+  VPrintf(1, "***** Running under ThreadSanitizer v2 (pid %d) *****\n",
+          (int)internal_getpid());
+
+  // Initialize thread 0.
+  int tid = ThreadCreate(thr, 0, 0, true);
+  CHECK_EQ(tid, 0);
+  ThreadStart(thr, tid, GetTid(), ThreadType::Regular);
+#if TSAN_CONTAINS_UBSAN
+  __ubsan::InitAsPlugin();
+#endif
+  ctx->initialized = true;
+
+#if !SANITIZER_GO
+  Symbolizer::LateInitialize();
+#endif
+
+  if (flags()->stop_on_start) {
+    Printf("ThreadSanitizer is suspended at startup (pid %d)."
+           " Call __tsan_resume().\n",
+           (int)internal_getpid());
+    while (__tsan_resumed == 0) {}
+  }
+
+  OnInitialize();
+}
+
+void MaybeSpawnBackgroundThread() {
+  // On MIPS, TSan initialization is run before
+  // __pthread_initialize_minimal_internal() is finished, so we can not spawn
+  // new threads.
+#if !SANITIZER_GO && !defined(__mips__)
+  static atomic_uint32_t bg_thread = {};
+  if (atomic_load(&bg_thread, memory_order_relaxed) == 0 &&
+      atomic_exchange(&bg_thread, 1, memory_order_relaxed) == 0) {
+    StartBackgroundThread();
+    SetSandboxingCallback(StopBackgroundThread);
+  }
+#endif
+}
+
+
+int Finalize(ThreadState *thr) {
+  bool failed = false;
+
+  if (common_flags()->print_module_map == 1) PrintModuleMap();
+
+  if (flags()->atexit_sleep_ms > 0 && ThreadCount(thr) > 1)
+    SleepForMillis(flags()->atexit_sleep_ms);
+
+  // Wait for pending reports.
+  ctx->report_mtx.Lock();
+  { ScopedErrorReportLock l; }
+  ctx->report_mtx.Unlock();
+
+#if !SANITIZER_GO
+  if (Verbosity()) AllocatorPrintStats();
+#endif
+
+  ThreadFinalize(thr);
+
+  if (ctx->nreported) {
+    failed = true;
+#if !SANITIZER_GO
+    Printf("ThreadSanitizer: reported %d warnings\n", ctx->nreported);
+#else
+    Printf("Found %d data race(s)\n", ctx->nreported);
+#endif
+  }
+
+  if (ctx->nmissed_expected) {
+    failed = true;
+    Printf("ThreadSanitizer: missed %d expected races\n",
+        ctx->nmissed_expected);
+  }
+
+  if (common_flags()->print_suppressions)
+    PrintMatchedSuppressions();
+#if !SANITIZER_GO
+  if (flags()->print_benign)
+    PrintMatchedBenignRaces();
+#endif
+
+  failed = OnFinalize(failed);
+
+#if TSAN_COLLECT_STATS
+  StatAggregate(ctx->stat, thr->stat);
+  StatOutput(ctx->stat);
+#endif
+
+  return failed ? common_flags()->exitcode : 0;
+}
+
+#if !SANITIZER_GO
+void ForkBefore(ThreadState *thr, uptr pc) {
+  ctx->thread_registry->Lock();
+  ctx->report_mtx.Lock();
+}
+
+void ForkParentAfter(ThreadState *thr, uptr pc) {
+  ctx->report_mtx.Unlock();
+  ctx->thread_registry->Unlock();
+}
+
+void ForkChildAfter(ThreadState *thr, uptr pc) {
+  ctx->report_mtx.Unlock();
+  ctx->thread_registry->Unlock();
+
+  uptr nthread = 0;
+  ctx->thread_registry->GetNumberOfThreads(0, 0, &nthread /* alive threads */);
+  VPrintf(1, "ThreadSanitizer: forked new process with pid %d,"
+      " parent had %d threads\n", (int)internal_getpid(), (int)nthread);
+  if (nthread == 1) {
+    StartBackgroundThread();
+  } else {
+    // We've just forked a multi-threaded process. We cannot reasonably function
+    // after that (some mutexes may be locked before fork). So just enable
+    // ignores for everything in the hope that we will exec soon.
+    ctx->after_multithreaded_fork = true;
+    thr->ignore_interceptors++;
+    ThreadIgnoreBegin(thr, pc);
+    ThreadIgnoreSyncBegin(thr, pc);
+  }
+}
+#endif
+
+#if SANITIZER_GO
+NOINLINE
+void GrowShadowStack(ThreadState *thr) {
+  const int sz = thr->shadow_stack_end - thr->shadow_stack;
+  const int newsz = 2 * sz;
+  uptr *newstack = (uptr*)internal_alloc(MBlockShadowStack,
+      newsz * sizeof(uptr));
+  internal_memcpy(newstack, thr->shadow_stack, sz * sizeof(uptr));
+  internal_free(thr->shadow_stack);
+  thr->shadow_stack = newstack;
+  thr->shadow_stack_pos = newstack + sz;
+  thr->shadow_stack_end = newstack + newsz;
+}
+#endif
+
+u32 CurrentStackId(ThreadState *thr, uptr pc) {
+  if (!thr->is_inited)  // May happen during bootstrap.
+    return 0;
+  if (pc != 0) {
+#if !SANITIZER_GO
+    DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
+#else
+    if (thr->shadow_stack_pos == thr->shadow_stack_end)
+      GrowShadowStack(thr);
+#endif
+    thr->shadow_stack_pos[0] = pc;
+    thr->shadow_stack_pos++;
+  }
+  u32 id = StackDepotPut(
+      StackTrace(thr->shadow_stack, thr->shadow_stack_pos - thr->shadow_stack));
+  if (pc != 0)
+    thr->shadow_stack_pos--;
+  return id;
+}
+
+void TraceSwitch(ThreadState *thr) {
+#if !SANITIZER_GO
+  if (ctx->after_multithreaded_fork)
+    return;
+#endif
+  thr->nomalloc++;
+  Trace *thr_trace = ThreadTrace(thr->tid);
+  Lock l(&thr_trace->mtx);
+  unsigned trace = (thr->fast_state.epoch() / kTracePartSize) % TraceParts();
+  TraceHeader *hdr = &thr_trace->headers[trace];
+  hdr->epoch0 = thr->fast_state.epoch();
+  ObtainCurrentStack(thr, 0, &hdr->stack0);
+  hdr->mset0 = thr->mset;
+  thr->nomalloc--;
+}
+
+Trace *ThreadTrace(int tid) {
+  return (Trace*)GetThreadTraceHeader(tid);
+}
+
+uptr TraceTopPC(ThreadState *thr) {
+  Event *events = (Event*)GetThreadTrace(thr->tid);
+  uptr pc = events[thr->fast_state.GetTracePos()];
+  return pc;
+}
+
+uptr TraceSize() {
+  return (uptr)(1ull << (kTracePartSizeBits + flags()->history_size + 1));
+}
+
+uptr TraceParts() {
+  return TraceSize() / kTracePartSize;
+}
+
+#if !SANITIZER_GO
+extern "C" void __tsan_trace_switch() {
+  TraceSwitch(cur_thread());
+}
+
+extern "C" void __tsan_report_race() {
+  ReportRace(cur_thread());
+}
+#endif
+
+ALWAYS_INLINE
+Shadow LoadShadow(u64 *p) {
+  u64 raw = atomic_load((atomic_uint64_t*)p, memory_order_relaxed);
+  return Shadow(raw);
+}
+
+ALWAYS_INLINE
+void StoreShadow(u64 *sp, u64 s) {
+  atomic_store((atomic_uint64_t*)sp, s, memory_order_relaxed);
+}
+
+ALWAYS_INLINE
+void StoreIfNotYetStored(u64 *sp, u64 *s) {
+  StoreShadow(sp, *s);
+  *s = 0;
+}
+
+ALWAYS_INLINE
+void HandleRace(ThreadState *thr, u64 *shadow_mem,
+                              Shadow cur, Shadow old) {
+  thr->racy_state[0] = cur.raw();
+  thr->racy_state[1] = old.raw();
+  thr->racy_shadow_addr = shadow_mem;
+#if !SANITIZER_GO
+  HACKY_CALL(__tsan_report_race);
+#else
+  ReportRace(thr);
+#endif
+}
+
+static inline bool HappensBefore(Shadow old, ThreadState *thr) {
+  return thr->clock.get(old.TidWithIgnore()) >= old.epoch();
+}
+
+ALWAYS_INLINE
+void MemoryAccessImpl1(ThreadState *thr, uptr addr,
+    int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
+    u64 *shadow_mem, Shadow cur) {
+  StatInc(thr, StatMop);
+  StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
+  StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
+
+  // This potentially can live in an MMX/SSE scratch register.
+  // The required intrinsics are:
+  // __m128i _mm_move_epi64(__m128i*);
+  // _mm_storel_epi64(u64*, __m128i);
+  u64 store_word = cur.raw();
+  bool stored = false;
+
+  // scan all the shadow values and dispatch to 4 categories:
+  // same, replace, candidate and race (see comments below).
+  // we consider only 3 cases regarding access sizes:
+  // equal, intersect and not intersect. initially I considered
+  // larger and smaller as well, it allowed to replace some
+  // 'candidates' with 'same' or 'replace', but I think
+  // it's just not worth it (performance- and complexity-wise).
+
+  Shadow old(0);
+
+  // It release mode we manually unroll the loop,
+  // because empirically gcc generates better code this way.
+  // However, we can't afford unrolling in debug mode, because the function
+  // consumes almost 4K of stack. Gtest gives only 4K of stack to death test
+  // threads, which is not enough for the unrolled loop.
+#if SANITIZER_DEBUG
+  for (int idx = 0; idx < 4; idx++) {
+#include "tsan_update_shadow_word_inl.h"
+  }
+#else
+  int idx = 0;
+#include "tsan_update_shadow_word_inl.h"
+  idx = 1;
+  if (stored) {
+#include "tsan_update_shadow_word_inl.h"
+  } else {
+#include "tsan_update_shadow_word_inl.h"
+  }
+  idx = 2;
+  if (stored) {
+#include "tsan_update_shadow_word_inl.h"
+  } else {
+#include "tsan_update_shadow_word_inl.h"
+  }
+  idx = 3;
+  if (stored) {
+#include "tsan_update_shadow_word_inl.h"
+  } else {
+#include "tsan_update_shadow_word_inl.h"
+  }
+#endif
+
+  // we did not find any races and had already stored
+  // the current access info, so we are done
+  if (LIKELY(stored))
+    return;
+  // choose a random candidate slot and replace it
+  StoreShadow(shadow_mem + (cur.epoch() % kShadowCnt), store_word);
+  StatInc(thr, StatShadowReplace);
+  return;
+ RACE:
+  HandleRace(thr, shadow_mem, cur, old);
+  return;
+}
+
+void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr,
+    int size, bool kAccessIsWrite, bool kIsAtomic) {
+  while (size) {
+    int size1 = 1;
+    int kAccessSizeLog = kSizeLog1;
+    if (size >= 8 && (addr & ~7) == ((addr + 7) & ~7)) {
+      size1 = 8;
+      kAccessSizeLog = kSizeLog8;
+    } else if (size >= 4 && (addr & ~7) == ((addr + 3) & ~7)) {
+      size1 = 4;
+      kAccessSizeLog = kSizeLog4;
+    } else if (size >= 2 && (addr & ~7) == ((addr + 1) & ~7)) {
+      size1 = 2;
+      kAccessSizeLog = kSizeLog2;
+    }
+    MemoryAccess(thr, pc, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic);
+    addr += size1;
+    size -= size1;
+  }
+}
+
+ALWAYS_INLINE
+bool ContainsSameAccessSlow(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
+  Shadow cur(a);
+  for (uptr i = 0; i < kShadowCnt; i++) {
+    Shadow old(LoadShadow(&s[i]));
+    if (Shadow::Addr0AndSizeAreEqual(cur, old) &&
+        old.TidWithIgnore() == cur.TidWithIgnore() &&
+        old.epoch() > sync_epoch &&
+        old.IsAtomic() == cur.IsAtomic() &&
+        old.IsRead() <= cur.IsRead())
+      return true;
+  }
+  return false;
+}
+
+#if defined(__SSE3__)
+#define SHUF(v0, v1, i0, i1, i2, i3) _mm_castps_si128(_mm_shuffle_ps( \
+    _mm_castsi128_ps(v0), _mm_castsi128_ps(v1), \
+    (i0)*1 + (i1)*4 + (i2)*16 + (i3)*64))
+ALWAYS_INLINE
+bool ContainsSameAccessFast(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
+  // This is an optimized version of ContainsSameAccessSlow.
+  // load current access into access[0:63]
+  const m128 access     = _mm_cvtsi64_si128(a);
+  // duplicate high part of access in addr0:
+  // addr0[0:31]        = access[32:63]
+  // addr0[32:63]       = access[32:63]
+  // addr0[64:95]       = access[32:63]
+  // addr0[96:127]      = access[32:63]
+  const m128 addr0      = SHUF(access, access, 1, 1, 1, 1);
+  // load 4 shadow slots
+  const m128 shadow0    = _mm_load_si128((__m128i*)s);
+  const m128 shadow1    = _mm_load_si128((__m128i*)s + 1);
+  // load high parts of 4 shadow slots into addr_vect:
+  // addr_vect[0:31]    = shadow0[32:63]
+  // addr_vect[32:63]   = shadow0[96:127]
+  // addr_vect[64:95]   = shadow1[32:63]
+  // addr_vect[96:127]  = shadow1[96:127]
+  m128 addr_vect        = SHUF(shadow0, shadow1, 1, 3, 1, 3);
+  if (!is_write) {
+    // set IsRead bit in addr_vect
+    const m128 rw_mask1 = _mm_cvtsi64_si128(1<<15);
+    const m128 rw_mask  = SHUF(rw_mask1, rw_mask1, 0, 0, 0, 0);
+    addr_vect           = _mm_or_si128(addr_vect, rw_mask);
+  }
+  // addr0 == addr_vect?
+  const m128 addr_res   = _mm_cmpeq_epi32(addr0, addr_vect);
+  // epoch1[0:63]       = sync_epoch
+  const m128 epoch1     = _mm_cvtsi64_si128(sync_epoch);
+  // epoch[0:31]        = sync_epoch[0:31]
+  // epoch[32:63]       = sync_epoch[0:31]
+  // epoch[64:95]       = sync_epoch[0:31]
+  // epoch[96:127]      = sync_epoch[0:31]
+  const m128 epoch      = SHUF(epoch1, epoch1, 0, 0, 0, 0);
+  // load low parts of shadow cell epochs into epoch_vect:
+  // epoch_vect[0:31]   = shadow0[0:31]
+  // epoch_vect[32:63]  = shadow0[64:95]
+  // epoch_vect[64:95]  = shadow1[0:31]
+  // epoch_vect[96:127] = shadow1[64:95]
+  const m128 epoch_vect = SHUF(shadow0, shadow1, 0, 2, 0, 2);
+  // epoch_vect >= sync_epoch?
+  const m128 epoch_res  = _mm_cmpgt_epi32(epoch_vect, epoch);
+  // addr_res & epoch_res
+  const m128 res        = _mm_and_si128(addr_res, epoch_res);
+  // mask[0] = res[7]
+  // mask[1] = res[15]
+  // ...
+  // mask[15] = res[127]
+  const int mask        = _mm_movemask_epi8(res);
+  return mask != 0;
+}
+#endif
+
+ALWAYS_INLINE
+bool ContainsSameAccess(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
+#if defined(__SSE3__)
+  bool res = ContainsSameAccessFast(s, a, sync_epoch, is_write);
+  // NOTE: this check can fail if the shadow is concurrently mutated
+  // by other threads. But it still can be useful if you modify
+  // ContainsSameAccessFast and want to ensure that it's not completely broken.
+  // DCHECK_EQ(res, ContainsSameAccessSlow(s, a, sync_epoch, is_write));
+  return res;
+#else
+  return ContainsSameAccessSlow(s, a, sync_epoch, is_write);
+#endif
+}
+
+ALWAYS_INLINE USED
+void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
+    int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic) {
+  u64 *shadow_mem = (u64*)MemToShadow(addr);
+  DPrintf2("#%d: MemoryAccess: @%p %p size=%d"
+      " is_write=%d shadow_mem=%p {%zx, %zx, %zx, %zx}\n",
+      (int)thr->fast_state.tid(), (void*)pc, (void*)addr,
+      (int)(1 << kAccessSizeLog), kAccessIsWrite, shadow_mem,
+      (uptr)shadow_mem[0], (uptr)shadow_mem[1],
+      (uptr)shadow_mem[2], (uptr)shadow_mem[3]);
+#if SANITIZER_DEBUG
+  if (!IsAppMem(addr)) {
+    Printf("Access to non app mem %zx\n", addr);
+    DCHECK(IsAppMem(addr));
+  }
+  if (!IsShadowMem((uptr)shadow_mem)) {
+    Printf("Bad shadow addr %p (%zx)\n", shadow_mem, addr);
+    DCHECK(IsShadowMem((uptr)shadow_mem));
+  }
+#endif
+
+  if (!SANITIZER_GO && !kAccessIsWrite && *shadow_mem == kShadowRodata) {
+    // Access to .rodata section, no races here.
+    // Measurements show that it can be 10-20% of all memory accesses.
+    StatInc(thr, StatMop);
+    StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
+    StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
+    StatInc(thr, StatMopRodata);
+    return;
+  }
+
+  FastState fast_state = thr->fast_state;
+  if (UNLIKELY(fast_state.GetIgnoreBit())) {
+    StatInc(thr, StatMop);
+    StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
+    StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
+    StatInc(thr, StatMopIgnored);
+    return;
+  }
+
+  Shadow cur(fast_state);
+  cur.SetAddr0AndSizeLog(addr & 7, kAccessSizeLog);
+  cur.SetWrite(kAccessIsWrite);
+  cur.SetAtomic(kIsAtomic);
+
+  if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(),
+      thr->fast_synch_epoch, kAccessIsWrite))) {
+    StatInc(thr, StatMop);
+    StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
+    StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
+    StatInc(thr, StatMopSame);
+    return;
+  }
+
+  if (kCollectHistory) {
+    fast_state.IncrementEpoch();
+    thr->fast_state = fast_state;
+    TraceAddEvent(thr, fast_state, EventTypeMop, pc);
+    cur.IncrementEpoch();
+  }
+
+  MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic,
+      shadow_mem, cur);
+}
+
+// Called by MemoryAccessRange in tsan_rtl_thread.cpp
+ALWAYS_INLINE USED
+void MemoryAccessImpl(ThreadState *thr, uptr addr,
+    int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
+    u64 *shadow_mem, Shadow cur) {
+  if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(),
+      thr->fast_synch_epoch, kAccessIsWrite))) {
+    StatInc(thr, StatMop);
+    StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
+    StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
+    StatInc(thr, StatMopSame);
+    return;
+  }
+
+  MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic,
+      shadow_mem, cur);
+}
+
+static void MemoryRangeSet(ThreadState *thr, uptr pc, uptr addr, uptr size,
+                           u64 val) {
+  (void)thr;
+  (void)pc;
+  if (size == 0)
+    return;
+  // FIXME: fix me.
+  uptr offset = addr % kShadowCell;
+  if (offset) {
+    offset = kShadowCell - offset;
+    if (size <= offset)
+      return;
+    addr += offset;
+    size -= offset;
+  }
+  DCHECK_EQ(addr % 8, 0);
+  // If a user passes some insane arguments (memset(0)),
+  // let it just crash as usual.
+  if (!IsAppMem(addr) || !IsAppMem(addr + size - 1))
+    return;
+  // Don't want to touch lots of shadow memory.
+  // If a program maps 10MB stack, there is no need reset the whole range.
+  size = (size + (kShadowCell - 1)) & ~(kShadowCell - 1);
+  // UnmapOrDie/MmapFixedNoReserve does not work on Windows.
+  if (SANITIZER_WINDOWS || size < common_flags()->clear_shadow_mmap_threshold) {
+    u64 *p = (u64*)MemToShadow(addr);
+    CHECK(IsShadowMem((uptr)p));
+    CHECK(IsShadowMem((uptr)(p + size * kShadowCnt / kShadowCell - 1)));
+    // FIXME: may overwrite a part outside the region
+    for (uptr i = 0; i < size / kShadowCell * kShadowCnt;) {
+      p[i++] = val;
+      for (uptr j = 1; j < kShadowCnt; j++)
+        p[i++] = 0;
+    }
+  } else {
+    // The region is big, reset only beginning and end.
+    const uptr kPageSize = GetPageSizeCached();
+    u64 *begin = (u64*)MemToShadow(addr);
+    u64 *end = begin + size / kShadowCell * kShadowCnt;
+    u64 *p = begin;
+    // Set at least first kPageSize/2 to page boundary.
+    while ((p < begin + kPageSize / kShadowSize / 2) || ((uptr)p % kPageSize)) {
+      *p++ = val;
+      for (uptr j = 1; j < kShadowCnt; j++)
+        *p++ = 0;
+    }
+    // Reset middle part.
+    u64 *p1 = p;
+    p = RoundDown(end, kPageSize);
+    UnmapOrDie((void*)p1, (uptr)p - (uptr)p1);
+    if (!MmapFixedNoReserve((uptr)p1, (uptr)p - (uptr)p1))
+      Die();
+    // Set the ending.
+    while (p < end) {
+      *p++ = val;
+      for (uptr j = 1; j < kShadowCnt; j++)
+        *p++ = 0;
+    }
+  }
+}
+
+void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size) {
+  MemoryRangeSet(thr, pc, addr, size, 0);
+}
+
+void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size) {
+  // Processing more than 1k (4k of shadow) is expensive,
+  // can cause excessive memory consumption (user does not necessary touch
+  // the whole range) and most likely unnecessary.
+  if (size > 1024)
+    size = 1024;
+  CHECK_EQ(thr->is_freeing, false);
+  thr->is_freeing = true;
+  MemoryAccessRange(thr, pc, addr, size, true);
+  thr->is_freeing = false;
+  if (kCollectHistory) {
+    thr->fast_state.IncrementEpoch();
+    TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
+  }
+  Shadow s(thr->fast_state);
+  s.ClearIgnoreBit();
+  s.MarkAsFreed();
+  s.SetWrite(true);
+  s.SetAddr0AndSizeLog(0, 3);
+  MemoryRangeSet(thr, pc, addr, size, s.raw());
+}
+
+void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size) {
+  if (kCollectHistory) {
+    thr->fast_state.IncrementEpoch();
+    TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
+  }
+  Shadow s(thr->fast_state);
+  s.ClearIgnoreBit();
+  s.SetWrite(true);
+  s.SetAddr0AndSizeLog(0, 3);
+  MemoryRangeSet(thr, pc, addr, size, s.raw());
+}
+
+void MemoryRangeImitateWriteOrResetRange(ThreadState *thr, uptr pc, uptr addr,
+                                         uptr size) {
+  if (thr->ignore_reads_and_writes == 0)
+    MemoryRangeImitateWrite(thr, pc, addr, size);
+  else
+    MemoryResetRange(thr, pc, addr, size);
+}
+
+ALWAYS_INLINE USED
+void FuncEntry(ThreadState *thr, uptr pc) {
+  StatInc(thr, StatFuncEnter);
+  DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc);
+  if (kCollectHistory) {
+    thr->fast_state.IncrementEpoch();
+    TraceAddEvent(thr, thr->fast_state, EventTypeFuncEnter, pc);
+  }
+
+  // Shadow stack maintenance can be replaced with
+  // stack unwinding during trace switch (which presumably must be faster).
+  DCHECK_GE(thr->shadow_stack_pos, thr->shadow_stack);
+#if !SANITIZER_GO
+  DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
+#else
+  if (thr->shadow_stack_pos == thr->shadow_stack_end)
+    GrowShadowStack(thr);
+#endif
+  thr->shadow_stack_pos[0] = pc;
+  thr->shadow_stack_pos++;
+}
+
+ALWAYS_INLINE USED
+void FuncExit(ThreadState *thr) {
+  StatInc(thr, StatFuncExit);
+  DPrintf2("#%d: FuncExit\n", (int)thr->fast_state.tid());
+  if (kCollectHistory) {
+    thr->fast_state.IncrementEpoch();
+    TraceAddEvent(thr, thr->fast_state, EventTypeFuncExit, 0);
+  }
+
+  DCHECK_GT(thr->shadow_stack_pos, thr->shadow_stack);
+#if !SANITIZER_GO
+  DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
+#endif
+  thr->shadow_stack_pos--;
+}
+
+void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack) {
+  DPrintf("#%d: ThreadIgnoreBegin\n", thr->tid);
+  thr->ignore_reads_and_writes++;
+  CHECK_GT(thr->ignore_reads_and_writes, 0);
+  thr->fast_state.SetIgnoreBit();
+#if !SANITIZER_GO
+  if (save_stack && !ctx->after_multithreaded_fork)
+    thr->mop_ignore_set.Add(CurrentStackId(thr, pc));
+#endif
+}
+
+void ThreadIgnoreEnd(ThreadState *thr, uptr pc) {
+  DPrintf("#%d: ThreadIgnoreEnd\n", thr->tid);
+  CHECK_GT(thr->ignore_reads_and_writes, 0);
+  thr->ignore_reads_and_writes--;
+  if (thr->ignore_reads_and_writes == 0) {
+    thr->fast_state.ClearIgnoreBit();
+#if !SANITIZER_GO
+    thr->mop_ignore_set.Reset();
+#endif
+  }
+}
+
+#if !SANITIZER_GO
+extern "C" SANITIZER_INTERFACE_ATTRIBUTE
+uptr __tsan_testonly_shadow_stack_current_size() {
+  ThreadState *thr = cur_thread();
+  return thr->shadow_stack_pos - thr->shadow_stack;
+}
+#endif
+
+void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc, bool save_stack) {
+  DPrintf("#%d: ThreadIgnoreSyncBegin\n", thr->tid);
+  thr->ignore_sync++;
+  CHECK_GT(thr->ignore_sync, 0);
+#if !SANITIZER_GO
+  if (save_stack && !ctx->after_multithreaded_fork)
+    thr->sync_ignore_set.Add(CurrentStackId(thr, pc));
+#endif
+}
+
+void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc) {
+  DPrintf("#%d: ThreadIgnoreSyncEnd\n", thr->tid);
+  CHECK_GT(thr->ignore_sync, 0);
+  thr->ignore_sync--;
+#if !SANITIZER_GO
+  if (thr->ignore_sync == 0)
+    thr->sync_ignore_set.Reset();
+#endif
+}
+
+bool MD5Hash::operator==(const MD5Hash &other) const {
+  return hash[0] == other.hash[0] && hash[1] == other.hash[1];
+}
+
+#if SANITIZER_DEBUG
+void build_consistency_debug() {}
+#else
+void build_consistency_release() {}
+#endif
+
+#if TSAN_COLLECT_STATS
+void build_consistency_stats() {}
+#else
+void build_consistency_nostats() {}
+#endif
+
+}  // namespace __tsan
+
+#if !SANITIZER_GO
+// Must be included in this file to make sure everything is inlined.
+#include "tsan_interface_inl.h"
+#endif