libsanitizer/tsan/tsan_rtl.cc

   1 //===-- tsan_rtl.cc -------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of ThreadSanitizer (TSan), a race detector.
   9 //
  10 // Main file (entry points) for the TSan run-time.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_common/sanitizer_atomic.h"
  14 #include "sanitizer_common/sanitizer_common.h"
  15 #include "sanitizer_common/sanitizer_libc.h"
  16 #include "sanitizer_common/sanitizer_stackdepot.h"
  17 #include "sanitizer_common/sanitizer_placement_new.h"
  18 #include "sanitizer_common/sanitizer_symbolizer.h"
  19 #include "tsan_defs.h"
  20 #include "tsan_platform.h"
  21 #include "tsan_rtl.h"
  22 #include "tsan_mman.h"
  23 #include "tsan_suppressions.h"
  24
  25 volatile int __tsan_resumed = 0;
  26
  27 extern "C" void __tsan_resume() {
  28   __tsan_resumed = 1;
  29 }
  30
  31 namespace __tsan {
  32
  33 #ifndef TSAN_GO
  34 THREADLOCAL char cur_thread_placeholder[sizeof(ThreadState)] ALIGNED(64);
  35 #endif
  36 static char ctx_placeholder[sizeof(Context)] ALIGNED(64);
  37
  38 static Context *ctx;
  39 Context *CTX() {
  40   return ctx;
  41 }
  42
  43 Context::Context()
  44   : initialized()
  45   , report_mtx(MutexTypeReport, StatMtxReport)
  46   , nreported()
  47   , nmissed_expected()
  48   , thread_mtx(MutexTypeThreads, StatMtxThreads)
  49   , racy_stacks(MBlockRacyStacks)
  50   , racy_addresses(MBlockRacyAddresses)
  51   , fired_suppressions(MBlockRacyAddresses) {
  52 }
  53
  54 // The objects are allocated in TLS, so one may rely on zero-initialization.
  55 ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
  56                          uptr stk_addr, uptr stk_size,
  57                          uptr tls_addr, uptr tls_size)
  58   : fast_state(tid, epoch)
  59   // Do not touch these, rely on zero initialization,
  60   // they may be accessed before the ctor.
  61   // , fast_ignore_reads()
  62   // , fast_ignore_writes()
  63   // , in_rtl()
  64   , shadow_stack_pos(&shadow_stack[0])
  65   , tid(tid)
  66   , unique_id(unique_id)
  67   , stk_addr(stk_addr)
  68   , stk_size(stk_size)
  69   , tls_addr(tls_addr)
  70   , tls_size(tls_size) {
  71 }
  72
  73 ThreadContext::ThreadContext(int tid)
  74   : tid(tid)
  75   , unique_id()
  76   , os_id()
  77   , user_id()
  78   , thr()
  79   , status(ThreadStatusInvalid)
  80   , detached()
  81   , reuse_count()
  82   , epoch0()
  83   , epoch1()
  84   , dead_info()
  85   , dead_next()
  86   , name() {
  87 }
  88
  89 static void WriteMemoryProfile(char *buf, uptr buf_size, int num) {
  90   uptr shadow = GetShadowMemoryConsumption();
  91
  92   int nthread = 0;
  93   int nlivethread = 0;
  94   uptr threadmem = 0;
  95   {
  96     Lock l(&ctx->thread_mtx);
  97     for (unsigned i = 0; i < kMaxTid; i++) {
  98       ThreadContext *tctx = ctx->threads[i];
  99       if (tctx == 0)
 100         continue;
 101       nthread += 1;
 102       threadmem += sizeof(ThreadContext);
 103       if (tctx->status != ThreadStatusRunning)
 104         continue;
 105       nlivethread += 1;
 106       threadmem += sizeof(ThreadState);
 107     }
 108   }
 109
 110   uptr nsync = 0;
 111   uptr syncmem = CTX()->synctab.GetMemoryConsumption(&nsync);
 112
 113   internal_snprintf(buf, buf_size, "%d: shadow=%zuMB"
 114                                    " thread=%zuMB(total=%d/live=%d)"
 115                                    " sync=%zuMB(cnt=%zu)\n",
 116     num,
 117     shadow >> 20,
 118     threadmem >> 20, nthread, nlivethread,
 119     syncmem >> 20, nsync);
 120 }
 121
 122 static void MemoryProfileThread(void *arg) {
 123   ScopedInRtl in_rtl;
 124   fd_t fd = (fd_t)(uptr)arg;
 125   for (int i = 0; ; i++) {
 126     InternalScopedBuffer<char> buf(4096);
 127     WriteMemoryProfile(buf.data(), buf.size(), i);
 128     internal_write(fd, buf.data(), internal_strlen(buf.data()));
 129     SleepForSeconds(1);
 130   }
 131 }
 132
 133 static void InitializeMemoryProfile() {
 134   if (flags()->profile_memory == 0 || flags()->profile_memory[0] == 0)
 135     return;
 136   InternalScopedBuffer<char> filename(4096);
 137   internal_snprintf(filename.data(), filename.size(), "%s.%d",
 138       flags()->profile_memory, GetPid());
 139   fd_t fd = internal_open(filename.data(), true);
 140   if (fd == kInvalidFd) {
 141     Printf("Failed to open memory profile file '%s'\n", &filename[0]);
 142     Die();
 143   }
 144   internal_start_thread(&MemoryProfileThread, (void*)(uptr)fd);
 145 }
 146
 147 static void MemoryFlushThread(void *arg) {
 148   ScopedInRtl in_rtl;
 149   for (int i = 0; ; i++) {
 150     SleepForMillis(flags()->flush_memory_ms);
 151     FlushShadowMemory();
 152   }
 153 }
 154
 155 static void InitializeMemoryFlush() {
 156   if (flags()->flush_memory_ms == 0)
 157     return;
 158   if (flags()->flush_memory_ms < 100)
 159     flags()->flush_memory_ms = 100;
 160   internal_start_thread(&MemoryFlushThread, 0);
 161 }
 162
 163 void MapShadow(uptr addr, uptr size) {
 164   MmapFixedNoReserve(MemToShadow(addr), size * kShadowMultiplier);
 165 }
 166
 167 void MapThreadTrace(uptr addr, uptr size) {
 168   DPrintf("#0: Mapping trace at %p-%p(0x%zx)\n", addr, addr + size, size);
 169   CHECK_GE(addr, kTraceMemBegin);
 170   CHECK_LE(addr + size, kTraceMemBegin + kTraceMemSize);
 171   if (addr != (uptr)MmapFixedNoReserve(addr, size)) {
 172     Printf("FATAL: ThreadSanitizer can not mmap thread trace\n");
 173     Die();
 174   }
 175 }
 176
 177 void Initialize(ThreadState *thr) {
 178   // Thread safe because done before all threads exist.
 179   static bool is_initialized = false;
 180   if (is_initialized)
 181     return;
 182   is_initialized = true;
 183   // Install tool-specific callbacks in sanitizer_common.
 184   SetCheckFailedCallback(TsanCheckFailed);
 185
 186   ScopedInRtl in_rtl;
 187 #ifndef TSAN_GO
 188   InitializeAllocator();
 189 #endif
 190   InitializeInterceptors();
 191   const char *env = InitializePlatform();
 192   InitializeMutex();
 193   InitializeDynamicAnnotations();
 194   ctx = new(ctx_placeholder) Context;
 195 #ifndef TSAN_GO
 196   InitializeShadowMemory();
 197 #endif
 198   ctx->dead_list_size = 0;
 199   ctx->dead_list_head = 0;
 200   ctx->dead_list_tail = 0;
 201   InitializeFlags(&ctx->flags, env);
 202   // Setup correct file descriptor for error reports.
 203   if (internal_strcmp(flags()->log_path, "stdout") == 0)
 204     __sanitizer_set_report_fd(kStdoutFd);
 205   else if (internal_strcmp(flags()->log_path, "stderr") == 0)
 206     __sanitizer_set_report_fd(kStderrFd);
 207   else
 208     __sanitizer_set_report_path(flags()->log_path);
 209   InitializeSuppressions();
 210 #ifndef TSAN_GO
 211   // Initialize external symbolizer before internal threads are started.
 212   const char *external_symbolizer = flags()->external_symbolizer_path;
 213   if (external_symbolizer != 0 && external_symbolizer[0] != '\0') {
 214     if (!InitializeExternalSymbolizer(external_symbolizer)) {
 215       Printf("Failed to start external symbolizer: '%s'\n",
 216              external_symbolizer);
 217       Die();
 218     }
 219   }
 220 #endif
 221   InitializeMemoryProfile();
 222   InitializeMemoryFlush();
 223
 224   if (ctx->flags.verbosity)
 225     Printf("***** Running under ThreadSanitizer v2 (pid %d) *****\n",
 226                GetPid());
 227
 228   // Initialize thread 0.
 229   ctx->thread_seq = 0;
 230   int tid = ThreadCreate(thr, 0, 0, true);
 231   CHECK_EQ(tid, 0);
 232   ThreadStart(thr, tid, GetPid());
 233   CHECK_EQ(thr->in_rtl, 1);
 234   ctx->initialized = true;
 235
 236   if (flags()->stop_on_start) {
 237     Printf("ThreadSanitizer is suspended at startup (pid %d)."
 238            " Call __tsan_resume().\n",
 239            GetPid());
 240     while (__tsan_resumed == 0);
 241   }
 242 }
 243
 244 int Finalize(ThreadState *thr) {
 245   ScopedInRtl in_rtl;
 246   Context *ctx = __tsan::ctx;
 247   bool failed = false;
 248
 249   if (flags()->atexit_sleep_ms > 0 && ThreadCount(thr) > 1)
 250     SleepForMillis(flags()->atexit_sleep_ms);
 251
 252   // Wait for pending reports.
 253   ctx->report_mtx.Lock();
 254   ctx->report_mtx.Unlock();
 255
 256   ThreadFinalize(thr);
 257
 258   if (ctx->nreported) {
 259     failed = true;
 260 #ifndef TSAN_GO
 261     Printf("ThreadSanitizer: reported %d warnings\n", ctx->nreported);
 262 #else
 263     Printf("Found %d data race(s)\n", ctx->nreported);
 264 #endif
 265   }
 266
 267   if (ctx->nmissed_expected) {
 268     failed = true;
 269     Printf("ThreadSanitizer: missed %d expected races\n",
 270         ctx->nmissed_expected);
 271   }
 272
 273   StatAggregate(ctx->stat, thr->stat);
 274   StatOutput(ctx->stat);
 275   return failed ? flags()->exitcode : 0;
 276 }
 277
 278 #ifndef TSAN_GO
 279 u32 CurrentStackId(ThreadState *thr, uptr pc) {
 280   if (thr->shadow_stack_pos == 0)  // May happen during bootstrap.
 281     return 0;
 282   if (pc) {
 283     thr->shadow_stack_pos[0] = pc;
 284     thr->shadow_stack_pos++;
 285   }
 286   u32 id = StackDepotPut(thr->shadow_stack,
 287                          thr->shadow_stack_pos - thr->shadow_stack);
 288   if (pc)
 289     thr->shadow_stack_pos--;
 290   return id;
 291 }
 292 #endif
 293
 294 void TraceSwitch(ThreadState *thr) {
 295   thr->nomalloc++;
 296   ScopedInRtl in_rtl;
 297   Lock l(&thr->trace.mtx);
 298   unsigned trace = (thr->fast_state.epoch() / kTracePartSize) % TraceParts();
 299   TraceHeader *hdr = &thr->trace.headers[trace];
 300   hdr->epoch0 = thr->fast_state.epoch();
 301   hdr->stack0.ObtainCurrent(thr, 0);
 302   hdr->mset0 = thr->mset;
 303   thr->nomalloc--;
 304 }
 305
 306 uptr TraceTopPC(ThreadState *thr) {
 307   Event *events = (Event*)GetThreadTrace(thr->tid);
 308   uptr pc = events[thr->fast_state.GetTracePos()];
 309   return pc;
 310 }
 311
 312 uptr TraceSize() {
 313   return (uptr)(1ull << (kTracePartSizeBits + flags()->history_size + 1));
 314 }
 315
 316 uptr TraceParts() {
 317   return TraceSize() / kTracePartSize;
 318 }
 319
 320 #ifndef TSAN_GO
 321 extern "C" void __tsan_trace_switch() {
 322   TraceSwitch(cur_thread());
 323 }
 324
 325 extern "C" void __tsan_report_race() {
 326   ReportRace(cur_thread());
 327 }
 328 #endif
 329
 330 ALWAYS_INLINE
 331 static Shadow LoadShadow(u64 *p) {
 332   u64 raw = atomic_load((atomic_uint64_t*)p, memory_order_relaxed);
 333   return Shadow(raw);
 334 }
 335
 336 ALWAYS_INLINE
 337 static void StoreShadow(u64 *sp, u64 s) {
 338   atomic_store((atomic_uint64_t*)sp, s, memory_order_relaxed);
 339 }
 340
 341 ALWAYS_INLINE
 342 static void StoreIfNotYetStored(u64 *sp, u64 *s) {
 343   StoreShadow(sp, *s);
 344   *s = 0;
 345 }
 346
 347 static inline void HandleRace(ThreadState *thr, u64 *shadow_mem,
 348                               Shadow cur, Shadow old) {
 349   thr->racy_state[0] = cur.raw();
 350   thr->racy_state[1] = old.raw();
 351   thr->racy_shadow_addr = shadow_mem;
 352 #ifndef TSAN_GO
 353   HACKY_CALL(__tsan_report_race);
 354 #else
 355   ReportRace(thr);
 356 #endif
 357 }
 358
 359 static inline bool BothReads(Shadow s, int kAccessIsWrite) {
 360   return !kAccessIsWrite && !s.is_write();
 361 }
 362
 363 static inline bool OldIsRWNotWeaker(Shadow old, int kAccessIsWrite) {
 364   return old.is_write() || !kAccessIsWrite;
 365 }
 366
 367 static inline bool OldIsRWWeakerOrEqual(Shadow old, int kAccessIsWrite) {
 368   return !old.is_write() || kAccessIsWrite;
 369 }
 370
 371 static inline bool OldIsInSameSynchEpoch(Shadow old, ThreadState *thr) {
 372   return old.epoch() >= thr->fast_synch_epoch;
 373 }
 374
 375 static inline bool HappensBefore(Shadow old, ThreadState *thr) {
 376   return thr->clock.get(old.TidWithIgnore()) >= old.epoch();
 377 }
 378
 379 ALWAYS_INLINE
 380 void MemoryAccessImpl(ThreadState *thr, uptr addr,
 381     int kAccessSizeLog, bool kAccessIsWrite,
 382     u64 *shadow_mem, Shadow cur) {
 383   StatInc(thr, StatMop);
 384   StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 385   StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 386
 387   // This potentially can live in an MMX/SSE scratch register.
 388   // The required intrinsics are:
 389   // __m128i _mm_move_epi64(__m128i*);
 390   // _mm_storel_epi64(u64*, __m128i);
 391   u64 store_word = cur.raw();
 392
 393   // scan all the shadow values and dispatch to 4 categories:
 394   // same, replace, candidate and race (see comments below).
 395   // we consider only 3 cases regarding access sizes:
 396   // equal, intersect and not intersect. initially I considered
 397   // larger and smaller as well, it allowed to replace some
 398   // 'candidates' with 'same' or 'replace', but I think
 399   // it's just not worth it (performance- and complexity-wise).
 400
 401   Shadow old(0);
 402   if (kShadowCnt == 1) {
 403     int idx = 0;
 404 #include "tsan_update_shadow_word_inl.h"
 405   } else if (kShadowCnt == 2) {
 406     int idx = 0;
 407 #include "tsan_update_shadow_word_inl.h"
 408     idx = 1;
 409 #include "tsan_update_shadow_word_inl.h"
 410   } else if (kShadowCnt == 4) {
 411     int idx = 0;
 412 #include "tsan_update_shadow_word_inl.h"
 413     idx = 1;
 414 #include "tsan_update_shadow_word_inl.h"
 415     idx = 2;
 416 #include "tsan_update_shadow_word_inl.h"
 417     idx = 3;
 418 #include "tsan_update_shadow_word_inl.h"
 419   } else if (kShadowCnt == 8) {
 420     int idx = 0;
 421 #include "tsan_update_shadow_word_inl.h"
 422     idx = 1;
 423 #include "tsan_update_shadow_word_inl.h"
 424     idx = 2;
 425 #include "tsan_update_shadow_word_inl.h"
 426     idx = 3;
 427 #include "tsan_update_shadow_word_inl.h"
 428     idx = 4;
 429 #include "tsan_update_shadow_word_inl.h"
 430     idx = 5;
 431 #include "tsan_update_shadow_word_inl.h"
 432     idx = 6;
 433 #include "tsan_update_shadow_word_inl.h"
 434     idx = 7;
 435 #include "tsan_update_shadow_word_inl.h"
 436   } else {
 437     CHECK(false);
 438   }
 439
 440   // we did not find any races and had already stored
 441   // the current access info, so we are done
 442   if (LIKELY(store_word == 0))
 443     return;
 444   // choose a random candidate slot and replace it
 445   StoreShadow(shadow_mem + (cur.epoch() % kShadowCnt), store_word);
 446   StatInc(thr, StatShadowReplace);
 447   return;
 448  RACE:
 449   HandleRace(thr, shadow_mem, cur, old);
 450   return;
 451 }
 452
 453 ALWAYS_INLINE
 454 void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
 455     int kAccessSizeLog, bool kAccessIsWrite) {
 456   u64 *shadow_mem = (u64*)MemToShadow(addr);
 457   DPrintf2("#%d: MemoryAccess: @%p %p size=%d"
 458       " is_write=%d shadow_mem=%p {%zx, %zx, %zx, %zx}\n",
 459       (int)thr->fast_state.tid(), (void*)pc, (void*)addr,
 460       (int)(1 << kAccessSizeLog), kAccessIsWrite, shadow_mem,
 461       (uptr)shadow_mem[0], (uptr)shadow_mem[1],
 462       (uptr)shadow_mem[2], (uptr)shadow_mem[3]);
 463 #if TSAN_DEBUG
 464   if (!IsAppMem(addr)) {
 465     Printf("Access to non app mem %zx\n", addr);
 466     DCHECK(IsAppMem(addr));
 467   }
 468   if (!IsShadowMem((uptr)shadow_mem)) {
 469     Printf("Bad shadow addr %p (%zx)\n", shadow_mem, addr);
 470     DCHECK(IsShadowMem((uptr)shadow_mem));
 471   }
 472 #endif
 473
 474   FastState fast_state = thr->fast_state;
 475   if (fast_state.GetIgnoreBit())
 476     return;
 477   fast_state.IncrementEpoch();
 478   thr->fast_state = fast_state;
 479   Shadow cur(fast_state);
 480   cur.SetAddr0AndSizeLog(addr & 7, kAccessSizeLog);
 481   cur.SetWrite(kAccessIsWrite);
 482
 483   // We must not store to the trace if we do not store to the shadow.
 484   // That is, this call must be moved somewhere below.
 485   TraceAddEvent(thr, fast_state, EventTypeMop, pc);
 486
 487   MemoryAccessImpl(thr, addr, kAccessSizeLog, kAccessIsWrite,
 488       shadow_mem, cur);
 489 }
 490
 491 static void MemoryRangeSet(ThreadState *thr, uptr pc, uptr addr, uptr size,
 492                            u64 val) {
 493   if (size == 0)
 494     return;
 495   // FIXME: fix me.
 496   uptr offset = addr % kShadowCell;
 497   if (offset) {
 498     offset = kShadowCell - offset;
 499     if (size <= offset)
 500       return;
 501     addr += offset;
 502     size -= offset;
 503   }
 504   DCHECK_EQ(addr % 8, 0);
 505   // If a user passes some insane arguments (memset(0)),
 506   // let it just crash as usual.
 507   if (!IsAppMem(addr) || !IsAppMem(addr + size - 1))
 508     return;
 509   (void)thr;
 510   (void)pc;
 511   // Some programs mmap like hundreds of GBs but actually used a small part.
 512   // So, it's better to report a false positive on the memory
 513   // then to hang here senselessly.
 514   const uptr kMaxResetSize = 4ull*1024*1024*1024;
 515   if (size > kMaxResetSize)
 516     size = kMaxResetSize;
 517   size = (size + (kShadowCell - 1)) & ~(kShadowCell - 1);
 518   u64 *p = (u64*)MemToShadow(addr);
 519   CHECK(IsShadowMem((uptr)p));
 520   CHECK(IsShadowMem((uptr)(p + size * kShadowCnt / kShadowCell - 1)));
 521   // FIXME: may overwrite a part outside the region
 522   for (uptr i = 0; i < size * kShadowCnt / kShadowCell;) {
 523     p[i++] = val;
 524     for (uptr j = 1; j < kShadowCnt; j++)
 525       p[i++] = 0;
 526   }
 527 }
 528
 529 void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 530   MemoryRangeSet(thr, pc, addr, size, 0);
 531 }
 532
 533 void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 534   MemoryAccessRange(thr, pc, addr, size, true);
 535   Shadow s(thr->fast_state);
 536   s.ClearIgnoreBit();
 537   s.MarkAsFreed();
 538   s.SetWrite(true);
 539   s.SetAddr0AndSizeLog(0, 3);
 540   MemoryRangeSet(thr, pc, addr, size, s.raw());
 541 }
 542
 543 void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 544   Shadow s(thr->fast_state);
 545   s.ClearIgnoreBit();
 546   s.SetWrite(true);
 547   s.SetAddr0AndSizeLog(0, 3);
 548   MemoryRangeSet(thr, pc, addr, size, s.raw());
 549 }
 550
 551 ALWAYS_INLINE
 552 void FuncEntry(ThreadState *thr, uptr pc) {
 553   DCHECK_EQ(thr->in_rtl, 0);
 554   StatInc(thr, StatFuncEnter);
 555   DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc);
 556   thr->fast_state.IncrementEpoch();
 557   TraceAddEvent(thr, thr->fast_state, EventTypeFuncEnter, pc);
 558
 559   // Shadow stack maintenance can be replaced with
 560   // stack unwinding during trace switch (which presumably must be faster).
 561   DCHECK_GE(thr->shadow_stack_pos, &thr->shadow_stack[0]);
 562 #ifndef TSAN_GO
 563   DCHECK_LT(thr->shadow_stack_pos, &thr->shadow_stack[kShadowStackSize]);
 564 #else
 565   if (thr->shadow_stack_pos == thr->shadow_stack_end) {
 566     const int sz = thr->shadow_stack_end - thr->shadow_stack;
 567     const int newsz = 2 * sz;
 568     uptr *newstack = (uptr*)internal_alloc(MBlockShadowStack,
 569         newsz * sizeof(uptr));
 570     internal_memcpy(newstack, thr->shadow_stack, sz * sizeof(uptr));
 571     internal_free(thr->shadow_stack);
 572     thr->shadow_stack = newstack;
 573     thr->shadow_stack_pos = newstack + sz;
 574     thr->shadow_stack_end = newstack + newsz;
 575   }
 576 #endif
 577   thr->shadow_stack_pos[0] = pc;
 578   thr->shadow_stack_pos++;
 579 }
 580
 581 ALWAYS_INLINE
 582 void FuncExit(ThreadState *thr) {
 583   DCHECK_EQ(thr->in_rtl, 0);
 584   StatInc(thr, StatFuncExit);
 585   DPrintf2("#%d: FuncExit\n", (int)thr->fast_state.tid());
 586   thr->fast_state.IncrementEpoch();
 587   TraceAddEvent(thr, thr->fast_state, EventTypeFuncExit, 0);
 588
 589   DCHECK_GT(thr->shadow_stack_pos, &thr->shadow_stack[0]);
 590 #ifndef TSAN_GO
 591   DCHECK_LT(thr->shadow_stack_pos, &thr->shadow_stack[kShadowStackSize]);
 592 #endif
 593   thr->shadow_stack_pos--;
 594 }
 595
 596 void IgnoreCtl(ThreadState *thr, bool write, bool begin) {
 597   DPrintf("#%d: IgnoreCtl(%d, %d)\n", thr->tid, write, begin);
 598   thr->ignore_reads_and_writes += begin ? 1 : -1;
 599   CHECK_GE(thr->ignore_reads_and_writes, 0);
 600   if (thr->ignore_reads_and_writes)
 601     thr->fast_state.SetIgnoreBit();
 602   else
 603     thr->fast_state.ClearIgnoreBit();
 604 }
 605
 606 bool MD5Hash::operator==(const MD5Hash &other) const {
 607   return hash[0] == other.hash[0] && hash[1] == other.hash[1];
 608 }
 609
 610 #if TSAN_DEBUG
 611 void build_consistency_debug() {}
 612 #else
 613 void build_consistency_release() {}
 614 #endif
 615
 616 #if TSAN_COLLECT_STATS
 617 void build_consistency_stats() {}
 618 #else
 619 void build_consistency_nostats() {}
 620 #endif
 621
 622 #if TSAN_SHADOW_COUNT == 1
 623 void build_consistency_shadow1() {}
 624 #elif TSAN_SHADOW_COUNT == 2
 625 void build_consistency_shadow2() {}
 626 #elif TSAN_SHADOW_COUNT == 4
 627 void build_consistency_shadow4() {}
 628 #else
 629 void build_consistency_shadow8() {}
 630 #endif
 631
 632 }  // namespace __tsan
 633
 634 #ifndef TSAN_GO
 635 // Must be included in this file to make sure everything is inlined.
 636 #include "tsan_interface_inl.h"
 637 #endif