libsanitizer/tsan/tsan_rtl.cpp

   1 //===-- tsan_rtl.cpp ------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a part of ThreadSanitizer (TSan), a race detector.
  10 //
  11 // Main file (entry points) for the TSan run-time.
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "sanitizer_common/sanitizer_atomic.h"
  15 #include "sanitizer_common/sanitizer_common.h"
  16 #include "sanitizer_common/sanitizer_file.h"
  17 #include "sanitizer_common/sanitizer_libc.h"
  18 #include "sanitizer_common/sanitizer_stackdepot.h"
  19 #include "sanitizer_common/sanitizer_placement_new.h"
  20 #include "sanitizer_common/sanitizer_symbolizer.h"
  21 #include "tsan_defs.h"
  22 #include "tsan_platform.h"
  23 #include "tsan_rtl.h"
  24 #include "tsan_mman.h"
  25 #include "tsan_suppressions.h"
  26 #include "tsan_symbolize.h"
  27 #include "ubsan/ubsan_init.h"
  28
  29 #ifdef __SSE3__
  30 // <emmintrin.h> transitively includes <stdlib.h>,
  31 // and it's prohibited to include std headers into tsan runtime.
  32 // So we do this dirty trick.
  33 #define _MM_MALLOC_H_INCLUDED
  34 #define __MM_MALLOC_H
  35 #include <emmintrin.h>
  36 typedef __m128i m128;
  37 #endif
  38
  39 volatile int __tsan_resumed = 0;
  40
  41 extern "C" void __tsan_resume() {
  42   __tsan_resumed = 1;
  43 }
  44
  45 namespace __tsan {
  46
  47 #if !SANITIZER_GO && !SANITIZER_MAC
  48 __attribute__((tls_model("initial-exec")))
  49 THREADLOCAL char cur_thread_placeholder[sizeof(ThreadState)] ALIGNED(64);
  50 #endif
  51 static char ctx_placeholder[sizeof(Context)] ALIGNED(64);
  52 Context *ctx;
  53
  54 // Can be overriden by a front-end.
  55 #ifdef TSAN_EXTERNAL_HOOKS
  56 bool OnFinalize(bool failed);
  57 void OnInitialize();
  58 #else
  59 SANITIZER_WEAK_CXX_DEFAULT_IMPL
  60 bool OnFinalize(bool failed) {
  61   return failed;
  62 }
  63 SANITIZER_WEAK_CXX_DEFAULT_IMPL
  64 void OnInitialize() {}
  65 #endif
  66
  67 static char thread_registry_placeholder[sizeof(ThreadRegistry)];
  68
  69 static ThreadContextBase *CreateThreadContext(u32 tid) {
  70   // Map thread trace when context is created.
  71   char name[50];
  72   internal_snprintf(name, sizeof(name), "trace %u", tid);
  73   MapThreadTrace(GetThreadTrace(tid), TraceSize() * sizeof(Event), name);
  74   const uptr hdr = GetThreadTraceHeader(tid);
  75   internal_snprintf(name, sizeof(name), "trace header %u", tid);
  76   MapThreadTrace(hdr, sizeof(Trace), name);
  77   new((void*)hdr) Trace();
  78   // We are going to use only a small part of the trace with the default
  79   // value of history_size. However, the constructor writes to the whole trace.
  80   // Unmap the unused part.
  81   uptr hdr_end = hdr + sizeof(Trace);
  82   hdr_end -= sizeof(TraceHeader) * (kTraceParts - TraceParts());
  83   hdr_end = RoundUp(hdr_end, GetPageSizeCached());
  84   if (hdr_end < hdr + sizeof(Trace))
  85     UnmapOrDie((void*)hdr_end, hdr + sizeof(Trace) - hdr_end);
  86   void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext));
  87   return new(mem) ThreadContext(tid);
  88 }
  89
  90 #if !SANITIZER_GO
  91 static const u32 kThreadQuarantineSize = 16;
  92 #else
  93 static const u32 kThreadQuarantineSize = 64;
  94 #endif
  95
  96 Context::Context()
  97   : initialized()
  98   , report_mtx(MutexTypeReport, StatMtxReport)
  99   , nreported()
 100   , nmissed_expected()
 101   , thread_registry(new(thread_registry_placeholder) ThreadRegistry(
 102       CreateThreadContext, kMaxTid, kThreadQuarantineSize, kMaxTidReuse))
 103   , racy_mtx(MutexTypeRacy, StatMtxRacy)
 104   , racy_stacks()
 105   , racy_addresses()
 106   , fired_suppressions_mtx(MutexTypeFired, StatMtxFired)
 107   , clock_alloc("clock allocator") {
 108   fired_suppressions.reserve(8);
 109 }
 110
 111 // The objects are allocated in TLS, so one may rely on zero-initialization.
 112 ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
 113                          unsigned reuse_count,
 114                          uptr stk_addr, uptr stk_size,
 115                          uptr tls_addr, uptr tls_size)
 116   : fast_state(tid, epoch)
 117   // Do not touch these, rely on zero initialization,
 118   // they may be accessed before the ctor.
 119   // , ignore_reads_and_writes()
 120   // , ignore_interceptors()
 121   , clock(tid, reuse_count)
 122 #if !SANITIZER_GO
 123   , jmp_bufs()
 124 #endif
 125   , tid(tid)
 126   , unique_id(unique_id)
 127   , stk_addr(stk_addr)
 128   , stk_size(stk_size)
 129   , tls_addr(tls_addr)
 130   , tls_size(tls_size)
 131 #if !SANITIZER_GO
 132   , last_sleep_clock(tid)
 133 #endif
 134 {
 135 }
 136
 137 #if !SANITIZER_GO
 138 static void MemoryProfiler(Context *ctx, fd_t fd, int i) {
 139   uptr n_threads;
 140   uptr n_running_threads;
 141   ctx->thread_registry->GetNumberOfThreads(&n_threads, &n_running_threads);
 142   InternalMmapVector<char> buf(4096);
 143   WriteMemoryProfile(buf.data(), buf.size(), n_threads, n_running_threads);
 144   WriteToFile(fd, buf.data(), internal_strlen(buf.data()));
 145 }
 146
 147 static void *BackgroundThread(void *arg) {
 148   // This is a non-initialized non-user thread, nothing to see here.
 149   // We don't use ScopedIgnoreInterceptors, because we want ignores to be
 150   // enabled even when the thread function exits (e.g. during pthread thread
 151   // shutdown code).
 152   cur_thread_init();
 153   cur_thread()->ignore_interceptors++;
 154   const u64 kMs2Ns = 1000 * 1000;
 155
 156   fd_t mprof_fd = kInvalidFd;
 157   if (flags()->profile_memory && flags()->profile_memory[0]) {
 158     if (internal_strcmp(flags()->profile_memory, "stdout") == 0) {
 159       mprof_fd = 1;
 160     } else if (internal_strcmp(flags()->profile_memory, "stderr") == 0) {
 161       mprof_fd = 2;
 162     } else {
 163       InternalScopedString filename(kMaxPathLength);
 164       filename.append("%s.%d", flags()->profile_memory, (int)internal_getpid());
 165       fd_t fd = OpenFile(filename.data(), WrOnly);
 166       if (fd == kInvalidFd) {
 167         Printf("ThreadSanitizer: failed to open memory profile file '%s'\n",
 168             &filename[0]);
 169       } else {
 170         mprof_fd = fd;
 171       }
 172     }
 173   }
 174
 175   u64 last_flush = NanoTime();
 176   uptr last_rss = 0;
 177   for (int i = 0;
 178       atomic_load(&ctx->stop_background_thread, memory_order_relaxed) == 0;
 179       i++) {
 180     SleepForMillis(100);
 181     u64 now = NanoTime();
 182
 183     // Flush memory if requested.
 184     if (flags()->flush_memory_ms > 0) {
 185       if (last_flush + flags()->flush_memory_ms * kMs2Ns < now) {
 186         VPrintf(1, "ThreadSanitizer: periodic memory flush\n");
 187         FlushShadowMemory();
 188         last_flush = NanoTime();
 189       }
 190     }
 191     // GetRSS can be expensive on huge programs, so don't do it every 100ms.
 192     if (flags()->memory_limit_mb > 0) {
 193       uptr rss = GetRSS();
 194       uptr limit = uptr(flags()->memory_limit_mb) << 20;
 195       VPrintf(1, "ThreadSanitizer: memory flush check"
 196                  " RSS=%llu LAST=%llu LIMIT=%llu\n",
 197               (u64)rss >> 20, (u64)last_rss >> 20, (u64)limit >> 20);
 198       if (2 * rss > limit + last_rss) {
 199         VPrintf(1, "ThreadSanitizer: flushing memory due to RSS\n");
 200         FlushShadowMemory();
 201         rss = GetRSS();
 202         VPrintf(1, "ThreadSanitizer: memory flushed RSS=%llu\n", (u64)rss>>20);
 203       }
 204       last_rss = rss;
 205     }
 206
 207     // Write memory profile if requested.
 208     if (mprof_fd != kInvalidFd)
 209       MemoryProfiler(ctx, mprof_fd, i);
 210
 211     // Flush symbolizer cache if requested.
 212     if (flags()->flush_symbolizer_ms > 0) {
 213       u64 last = atomic_load(&ctx->last_symbolize_time_ns,
 214                              memory_order_relaxed);
 215       if (last != 0 && last + flags()->flush_symbolizer_ms * kMs2Ns < now) {
 216         Lock l(&ctx->report_mtx);
 217         ScopedErrorReportLock l2;
 218         SymbolizeFlush();
 219         atomic_store(&ctx->last_symbolize_time_ns, 0, memory_order_relaxed);
 220       }
 221     }
 222   }
 223   return nullptr;
 224 }
 225
 226 static void StartBackgroundThread() {
 227   ctx->background_thread = internal_start_thread(&BackgroundThread, 0);
 228 }
 229
 230 #ifndef __mips__
 231 static void StopBackgroundThread() {
 232   atomic_store(&ctx->stop_background_thread, 1, memory_order_relaxed);
 233   internal_join_thread(ctx->background_thread);
 234   ctx->background_thread = 0;
 235 }
 236 #endif
 237 #endif
 238
 239 void DontNeedShadowFor(uptr addr, uptr size) {
 240   ReleaseMemoryPagesToOS(MemToShadow(addr), MemToShadow(addr + size));
 241 }
 242
 243 #if !SANITIZER_GO
 244 void UnmapShadow(ThreadState *thr, uptr addr, uptr size) {
 245   if (size == 0) return;
 246   DontNeedShadowFor(addr, size);
 247   ScopedGlobalProcessor sgp;
 248   ctx->metamap.ResetRange(thr->proc(), addr, size);
 249 }
 250 #endif
 251
 252 void MapShadow(uptr addr, uptr size) {
 253   // Global data is not 64K aligned, but there are no adjacent mappings,
 254   // so we can get away with unaligned mapping.
 255   // CHECK_EQ(addr, addr & ~((64 << 10) - 1));  // windows wants 64K alignment
 256   const uptr kPageSize = GetPageSizeCached();
 257   uptr shadow_begin = RoundDownTo((uptr)MemToShadow(addr), kPageSize);
 258   uptr shadow_end = RoundUpTo((uptr)MemToShadow(addr + size), kPageSize);
 259   if (!MmapFixedNoReserve(shadow_begin, shadow_end - shadow_begin, "shadow"))
 260     Die();
 261
 262   // Meta shadow is 2:1, so tread carefully.
 263   static bool data_mapped = false;
 264   static uptr mapped_meta_end = 0;
 265   uptr meta_begin = (uptr)MemToMeta(addr);
 266   uptr meta_end = (uptr)MemToMeta(addr + size);
 267   meta_begin = RoundDownTo(meta_begin, 64 << 10);
 268   meta_end = RoundUpTo(meta_end, 64 << 10);
 269   if (!data_mapped) {
 270     // First call maps data+bss.
 271     data_mapped = true;
 272     if (!MmapFixedNoReserve(meta_begin, meta_end - meta_begin, "meta shadow"))
 273       Die();
 274   } else {
 275     // Mapping continous heap.
 276     // Windows wants 64K alignment.
 277     meta_begin = RoundDownTo(meta_begin, 64 << 10);
 278     meta_end = RoundUpTo(meta_end, 64 << 10);
 279     if (meta_end <= mapped_meta_end)
 280       return;
 281     if (meta_begin < mapped_meta_end)
 282       meta_begin = mapped_meta_end;
 283     if (!MmapFixedNoReserve(meta_begin, meta_end - meta_begin, "meta shadow"))
 284       Die();
 285     mapped_meta_end = meta_end;
 286   }
 287   VPrintf(2, "mapped meta shadow for (%p-%p) at (%p-%p)\n",
 288       addr, addr+size, meta_begin, meta_end);
 289 }
 290
 291 void MapThreadTrace(uptr addr, uptr size, const char *name) {
 292   DPrintf("#0: Mapping trace at %p-%p(0x%zx)\n", addr, addr + size, size);
 293   CHECK_GE(addr, TraceMemBeg());
 294   CHECK_LE(addr + size, TraceMemEnd());
 295   CHECK_EQ(addr, addr & ~((64 << 10) - 1));  // windows wants 64K alignment
 296   if (!MmapFixedNoReserve(addr, size, name)) {
 297     Printf("FATAL: ThreadSanitizer can not mmap thread trace (%p/%p)\n",
 298         addr, size);
 299     Die();
 300   }
 301 }
 302
 303 static void CheckShadowMapping() {
 304   uptr beg, end;
 305   for (int i = 0; GetUserRegion(i, &beg, &end); i++) {
 306     // Skip cases for empty regions (heap definition for architectures that
 307     // do not use 64-bit allocator).
 308     if (beg == end)
 309       continue;
 310     VPrintf(3, "checking shadow region %p-%p\n", beg, end);
 311     uptr prev = 0;
 312     for (uptr p0 = beg; p0 <= end; p0 += (end - beg) / 4) {
 313       for (int x = -(int)kShadowCell; x <= (int)kShadowCell; x += kShadowCell) {
 314         const uptr p = RoundDown(p0 + x, kShadowCell);
 315         if (p < beg || p >= end)
 316           continue;
 317         const uptr s = MemToShadow(p);
 318         const uptr m = (uptr)MemToMeta(p);
 319         VPrintf(3, "  checking pointer %p: shadow=%p meta=%p\n", p, s, m);
 320         CHECK(IsAppMem(p));
 321         CHECK(IsShadowMem(s));
 322         CHECK_EQ(p, ShadowToMem(s));
 323         CHECK(IsMetaMem(m));
 324         if (prev) {
 325           // Ensure that shadow and meta mappings are linear within a single
 326           // user range. Lots of code that processes memory ranges assumes it.
 327           const uptr prev_s = MemToShadow(prev);
 328           const uptr prev_m = (uptr)MemToMeta(prev);
 329           CHECK_EQ(s - prev_s, (p - prev) * kShadowMultiplier);
 330           CHECK_EQ((m - prev_m) / kMetaShadowSize,
 331                    (p - prev) / kMetaShadowCell);
 332         }
 333         prev = p;
 334       }
 335     }
 336   }
 337 }
 338
 339 #if !SANITIZER_GO
 340 static void OnStackUnwind(const SignalContext &sig, const void *,
 341                           BufferedStackTrace *stack) {
 342   stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
 343                 common_flags()->fast_unwind_on_fatal);
 344 }
 345
 346 static void TsanOnDeadlySignal(int signo, void *siginfo, void *context) {
 347   HandleDeadlySignal(siginfo, context, GetTid(), &OnStackUnwind, nullptr);
 348 }
 349 #endif
 350
 351 void Initialize(ThreadState *thr) {
 352   // Thread safe because done before all threads exist.
 353   static bool is_initialized = false;
 354   if (is_initialized)
 355     return;
 356   is_initialized = true;
 357   // We are not ready to handle interceptors yet.
 358   ScopedIgnoreInterceptors ignore;
 359   SanitizerToolName = "ThreadSanitizer";
 360   // Install tool-specific callbacks in sanitizer_common.
 361   SetCheckFailedCallback(TsanCheckFailed);
 362
 363   ctx = new(ctx_placeholder) Context;
 364   const char *env_name = SANITIZER_GO ? "GORACE" : "TSAN_OPTIONS";
 365   const char *options = GetEnv(env_name);
 366   CacheBinaryName();
 367   CheckASLR();
 368   InitializeFlags(&ctx->flags, options, env_name);
 369   AvoidCVE_2016_2143();
 370   __sanitizer::InitializePlatformEarly();
 371   __tsan::InitializePlatformEarly();
 372
 373 #if !SANITIZER_GO
 374   // Re-exec ourselves if we need to set additional env or command line args.
 375   MaybeReexec();
 376
 377   InitializeAllocator();
 378   ReplaceSystemMalloc();
 379 #endif
 380   if (common_flags()->detect_deadlocks)
 381     ctx->dd = DDetector::Create(flags());
 382   Processor *proc = ProcCreate();
 383   ProcWire(proc, thr);
 384   InitializeInterceptors();
 385   CheckShadowMapping();
 386   InitializePlatform();
 387   InitializeMutex();
 388   InitializeDynamicAnnotations();
 389 #if !SANITIZER_GO
 390   InitializeShadowMemory();
 391   InitializeAllocatorLate();
 392   InstallDeadlySignalHandlers(TsanOnDeadlySignal);
 393 #endif
 394   // Setup correct file descriptor for error reports.
 395   __sanitizer_set_report_path(common_flags()->log_path);
 396   InitializeSuppressions();
 397 #if !SANITIZER_GO
 398   InitializeLibIgnore();
 399   Symbolizer::GetOrInit()->AddHooks(EnterSymbolizer, ExitSymbolizer);
 400 #endif
 401
 402   VPrintf(1, "***** Running under ThreadSanitizer v2 (pid %d) *****\n",
 403           (int)internal_getpid());
 404
 405   // Initialize thread 0.
 406   int tid = ThreadCreate(thr, 0, 0, true);
 407   CHECK_EQ(tid, 0);
 408   ThreadStart(thr, tid, GetTid(), ThreadType::Regular);
 409 #if TSAN_CONTAINS_UBSAN
 410   __ubsan::InitAsPlugin();
 411 #endif
 412   ctx->initialized = true;
 413
 414 #if !SANITIZER_GO
 415   Symbolizer::LateInitialize();
 416 #endif
 417
 418   if (flags()->stop_on_start) {
 419     Printf("ThreadSanitizer is suspended at startup (pid %d)."
 420            " Call __tsan_resume().\n",
 421            (int)internal_getpid());
 422     while (__tsan_resumed == 0) {}
 423   }
 424
 425   OnInitialize();
 426 }
 427
 428 void MaybeSpawnBackgroundThread() {
 429   // On MIPS, TSan initialization is run before
 430   // __pthread_initialize_minimal_internal() is finished, so we can not spawn
 431   // new threads.
 432 #if !SANITIZER_GO && !defined(__mips__)
 433   static atomic_uint32_t bg_thread = {};
 434   if (atomic_load(&bg_thread, memory_order_relaxed) == 0 &&
 435       atomic_exchange(&bg_thread, 1, memory_order_relaxed) == 0) {
 436     StartBackgroundThread();
 437     SetSandboxingCallback(StopBackgroundThread);
 438   }
 439 #endif
 440 }
 441
 442
 443 int Finalize(ThreadState *thr) {
 444   bool failed = false;
 445
 446   if (common_flags()->print_module_map == 1) PrintModuleMap();
 447
 448   if (flags()->atexit_sleep_ms > 0 && ThreadCount(thr) > 1)
 449     SleepForMillis(flags()->atexit_sleep_ms);
 450
 451   // Wait for pending reports.
 452   ctx->report_mtx.Lock();
 453   { ScopedErrorReportLock l; }
 454   ctx->report_mtx.Unlock();
 455
 456 #if !SANITIZER_GO
 457   if (Verbosity()) AllocatorPrintStats();
 458 #endif
 459
 460   ThreadFinalize(thr);
 461
 462   if (ctx->nreported) {
 463     failed = true;
 464 #if !SANITIZER_GO
 465     Printf("ThreadSanitizer: reported %d warnings\n", ctx->nreported);
 466 #else
 467     Printf("Found %d data race(s)\n", ctx->nreported);
 468 #endif
 469   }
 470
 471   if (ctx->nmissed_expected) {
 472     failed = true;
 473     Printf("ThreadSanitizer: missed %d expected races\n",
 474         ctx->nmissed_expected);
 475   }
 476
 477   if (common_flags()->print_suppressions)
 478     PrintMatchedSuppressions();
 479 #if !SANITIZER_GO
 480   if (flags()->print_benign)
 481     PrintMatchedBenignRaces();
 482 #endif
 483
 484   failed = OnFinalize(failed);
 485
 486 #if TSAN_COLLECT_STATS
 487   StatAggregate(ctx->stat, thr->stat);
 488   StatOutput(ctx->stat);
 489 #endif
 490
 491   return failed ? common_flags()->exitcode : 0;
 492 }
 493
 494 #if !SANITIZER_GO
 495 void ForkBefore(ThreadState *thr, uptr pc) {
 496   ctx->thread_registry->Lock();
 497   ctx->report_mtx.Lock();
 498   // Ignore memory accesses in the pthread_atfork callbacks.
 499   // If any of them triggers a data race we will deadlock
 500   // on the report_mtx.
 501   // We could ignore interceptors and sync operations as well,
 502   // but so far it's unclear if it will do more good or harm.
 503   // Unnecessarily ignoring things can lead to false positives later.
 504   ThreadIgnoreBegin(thr, pc);
 505 }
 506
 507 void ForkParentAfter(ThreadState *thr, uptr pc) {
 508   ThreadIgnoreEnd(thr, pc);  // Begin is in ForkBefore.
 509   ctx->report_mtx.Unlock();
 510   ctx->thread_registry->Unlock();
 511 }
 512
 513 void ForkChildAfter(ThreadState *thr, uptr pc) {
 514   ThreadIgnoreEnd(thr, pc);  // Begin is in ForkBefore.
 515   ctx->report_mtx.Unlock();
 516   ctx->thread_registry->Unlock();
 517
 518   uptr nthread = 0;
 519   ctx->thread_registry->GetNumberOfThreads(0, 0, &nthread /* alive threads */);
 520   VPrintf(1, "ThreadSanitizer: forked new process with pid %d,"
 521       " parent had %d threads\n", (int)internal_getpid(), (int)nthread);
 522   if (nthread == 1) {
 523     StartBackgroundThread();
 524   } else {
 525     // We've just forked a multi-threaded process. We cannot reasonably function
 526     // after that (some mutexes may be locked before fork). So just enable
 527     // ignores for everything in the hope that we will exec soon.
 528     ctx->after_multithreaded_fork = true;
 529     thr->ignore_interceptors++;
 530     ThreadIgnoreBegin(thr, pc);
 531     ThreadIgnoreSyncBegin(thr, pc);
 532   }
 533 }
 534 #endif
 535
 536 #if SANITIZER_GO
 537 NOINLINE
 538 void GrowShadowStack(ThreadState *thr) {
 539   const int sz = thr->shadow_stack_end - thr->shadow_stack;
 540   const int newsz = 2 * sz;
 541   uptr *newstack = (uptr*)internal_alloc(MBlockShadowStack,
 542       newsz * sizeof(uptr));
 543   internal_memcpy(newstack, thr->shadow_stack, sz * sizeof(uptr));
 544   internal_free(thr->shadow_stack);
 545   thr->shadow_stack = newstack;
 546   thr->shadow_stack_pos = newstack + sz;
 547   thr->shadow_stack_end = newstack + newsz;
 548 }
 549 #endif
 550
 551 u32 CurrentStackId(ThreadState *thr, uptr pc) {
 552   if (!thr->is_inited)  // May happen during bootstrap.
 553     return 0;
 554   if (pc != 0) {
 555 #if !SANITIZER_GO
 556     DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
 557 #else
 558     if (thr->shadow_stack_pos == thr->shadow_stack_end)
 559       GrowShadowStack(thr);
 560 #endif
 561     thr->shadow_stack_pos[0] = pc;
 562     thr->shadow_stack_pos++;
 563   }
 564   u32 id = StackDepotPut(
 565       StackTrace(thr->shadow_stack, thr->shadow_stack_pos - thr->shadow_stack));
 566   if (pc != 0)
 567     thr->shadow_stack_pos--;
 568   return id;
 569 }
 570
 571 void TraceSwitch(ThreadState *thr) {
 572 #if !SANITIZER_GO
 573   if (ctx->after_multithreaded_fork)
 574     return;
 575 #endif
 576   thr->nomalloc++;
 577   Trace *thr_trace = ThreadTrace(thr->tid);
 578   Lock l(&thr_trace->mtx);
 579   unsigned trace = (thr->fast_state.epoch() / kTracePartSize) % TraceParts();
 580   TraceHeader *hdr = &thr_trace->headers[trace];
 581   hdr->epoch0 = thr->fast_state.epoch();
 582   ObtainCurrentStack(thr, 0, &hdr->stack0);
 583   hdr->mset0 = thr->mset;
 584   thr->nomalloc--;
 585 }
 586
 587 Trace *ThreadTrace(int tid) {
 588   return (Trace*)GetThreadTraceHeader(tid);
 589 }
 590
 591 uptr TraceTopPC(ThreadState *thr) {
 592   Event *events = (Event*)GetThreadTrace(thr->tid);
 593   uptr pc = events[thr->fast_state.GetTracePos()];
 594   return pc;
 595 }
 596
 597 uptr TraceSize() {
 598   return (uptr)(1ull << (kTracePartSizeBits + flags()->history_size + 1));
 599 }
 600
 601 uptr TraceParts() {
 602   return TraceSize() / kTracePartSize;
 603 }
 604
 605 #if !SANITIZER_GO
 606 extern "C" void __tsan_trace_switch() {
 607   TraceSwitch(cur_thread());
 608 }
 609
 610 extern "C" void __tsan_report_race() {
 611   ReportRace(cur_thread());
 612 }
 613 #endif
 614
 615 ALWAYS_INLINE
 616 Shadow LoadShadow(u64 *p) {
 617   u64 raw = atomic_load((atomic_uint64_t*)p, memory_order_relaxed);
 618   return Shadow(raw);
 619 }
 620
 621 ALWAYS_INLINE
 622 void StoreShadow(u64 *sp, u64 s) {
 623   atomic_store((atomic_uint64_t*)sp, s, memory_order_relaxed);
 624 }
 625
 626 ALWAYS_INLINE
 627 void StoreIfNotYetStored(u64 *sp, u64 *s) {
 628   StoreShadow(sp, *s);
 629   *s = 0;
 630 }
 631
 632 ALWAYS_INLINE
 633 void HandleRace(ThreadState *thr, u64 *shadow_mem,
 634                               Shadow cur, Shadow old) {
 635   thr->racy_state[0] = cur.raw();
 636   thr->racy_state[1] = old.raw();
 637   thr->racy_shadow_addr = shadow_mem;
 638 #if !SANITIZER_GO
 639   HACKY_CALL(__tsan_report_race);
 640 #else
 641   ReportRace(thr);
 642 #endif
 643 }
 644
 645 static inline bool HappensBefore(Shadow old, ThreadState *thr) {
 646   return thr->clock.get(old.TidWithIgnore()) >= old.epoch();
 647 }
 648
 649 ALWAYS_INLINE
 650 void MemoryAccessImpl1(ThreadState *thr, uptr addr,
 651     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
 652     u64 *shadow_mem, Shadow cur) {
 653   StatInc(thr, StatMop);
 654   StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 655   StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 656
 657   // This potentially can live in an MMX/SSE scratch register.
 658   // The required intrinsics are:
 659   // __m128i _mm_move_epi64(__m128i*);
 660   // _mm_storel_epi64(u64*, __m128i);
 661   u64 store_word = cur.raw();
 662   bool stored = false;
 663
 664   // scan all the shadow values and dispatch to 4 categories:
 665   // same, replace, candidate and race (see comments below).
 666   // we consider only 3 cases regarding access sizes:
 667   // equal, intersect and not intersect. initially I considered
 668   // larger and smaller as well, it allowed to replace some
 669   // 'candidates' with 'same' or 'replace', but I think
 670   // it's just not worth it (performance- and complexity-wise).
 671
 672   Shadow old(0);
 673
 674   // It release mode we manually unroll the loop,
 675   // because empirically gcc generates better code this way.
 676   // However, we can't afford unrolling in debug mode, because the function
 677   // consumes almost 4K of stack. Gtest gives only 4K of stack to death test
 678   // threads, which is not enough for the unrolled loop.
 679 #if SANITIZER_DEBUG
 680   for (int idx = 0; idx < 4; idx++) {
 681 #include "tsan_update_shadow_word_inl.h"
 682   }
 683 #else
 684   int idx = 0;
 685 #include "tsan_update_shadow_word_inl.h"
 686   idx = 1;
 687   if (stored) {
 688 #include "tsan_update_shadow_word_inl.h"
 689   } else {
 690 #include "tsan_update_shadow_word_inl.h"
 691   }
 692   idx = 2;
 693   if (stored) {
 694 #include "tsan_update_shadow_word_inl.h"
 695   } else {
 696 #include "tsan_update_shadow_word_inl.h"
 697   }
 698   idx = 3;
 699   if (stored) {
 700 #include "tsan_update_shadow_word_inl.h"
 701   } else {
 702 #include "tsan_update_shadow_word_inl.h"
 703   }
 704 #endif
 705
 706   // we did not find any races and had already stored
 707   // the current access info, so we are done
 708   if (LIKELY(stored))
 709     return;
 710   // choose a random candidate slot and replace it
 711   StoreShadow(shadow_mem + (cur.epoch() % kShadowCnt), store_word);
 712   StatInc(thr, StatShadowReplace);
 713   return;
 714  RACE:
 715   HandleRace(thr, shadow_mem, cur, old);
 716   return;
 717 }
 718
 719 void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr,
 720     int size, bool kAccessIsWrite, bool kIsAtomic) {
 721   while (size) {
 722     int size1 = 1;
 723     int kAccessSizeLog = kSizeLog1;
 724     if (size >= 8 && (addr & ~7) == ((addr + 7) & ~7)) {
 725       size1 = 8;
 726       kAccessSizeLog = kSizeLog8;
 727     } else if (size >= 4 && (addr & ~7) == ((addr + 3) & ~7)) {
 728       size1 = 4;
 729       kAccessSizeLog = kSizeLog4;
 730     } else if (size >= 2 && (addr & ~7) == ((addr + 1) & ~7)) {
 731       size1 = 2;
 732       kAccessSizeLog = kSizeLog2;
 733     }
 734     MemoryAccess(thr, pc, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic);
 735     addr += size1;
 736     size -= size1;
 737   }
 738 }
 739
 740 ALWAYS_INLINE
 741 bool ContainsSameAccessSlow(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
 742   Shadow cur(a);
 743   for (uptr i = 0; i < kShadowCnt; i++) {
 744     Shadow old(LoadShadow(&s[i]));
 745     if (Shadow::Addr0AndSizeAreEqual(cur, old) &&
 746         old.TidWithIgnore() == cur.TidWithIgnore() &&
 747         old.epoch() > sync_epoch &&
 748         old.IsAtomic() == cur.IsAtomic() &&
 749         old.IsRead() <= cur.IsRead())
 750       return true;
 751   }
 752   return false;
 753 }
 754
 755 #if defined(__SSE3__)
 756 #define SHUF(v0, v1, i0, i1, i2, i3) _mm_castps_si128(_mm_shuffle_ps( \
 757     _mm_castsi128_ps(v0), _mm_castsi128_ps(v1), \
 758     (i0)*1 + (i1)*4 + (i2)*16 + (i3)*64))
 759 ALWAYS_INLINE
 760 bool ContainsSameAccessFast(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
 761   // This is an optimized version of ContainsSameAccessSlow.
 762   // load current access into access[0:63]
 763   const m128 access     = _mm_cvtsi64_si128(a);
 764   // duplicate high part of access in addr0:
 765   // addr0[0:31]        = access[32:63]
 766   // addr0[32:63]       = access[32:63]
 767   // addr0[64:95]       = access[32:63]
 768   // addr0[96:127]      = access[32:63]
 769   const m128 addr0      = SHUF(access, access, 1, 1, 1, 1);
 770   // load 4 shadow slots
 771   const m128 shadow0    = _mm_load_si128((__m128i*)s);
 772   const m128 shadow1    = _mm_load_si128((__m128i*)s + 1);
 773   // load high parts of 4 shadow slots into addr_vect:
 774   // addr_vect[0:31]    = shadow0[32:63]
 775   // addr_vect[32:63]   = shadow0[96:127]
 776   // addr_vect[64:95]   = shadow1[32:63]
 777   // addr_vect[96:127]  = shadow1[96:127]
 778   m128 addr_vect        = SHUF(shadow0, shadow1, 1, 3, 1, 3);
 779   if (!is_write) {
 780     // set IsRead bit in addr_vect
 781     const m128 rw_mask1 = _mm_cvtsi64_si128(1<<15);
 782     const m128 rw_mask  = SHUF(rw_mask1, rw_mask1, 0, 0, 0, 0);
 783     addr_vect           = _mm_or_si128(addr_vect, rw_mask);
 784   }
 785   // addr0 == addr_vect?
 786   const m128 addr_res   = _mm_cmpeq_epi32(addr0, addr_vect);
 787   // epoch1[0:63]       = sync_epoch
 788   const m128 epoch1     = _mm_cvtsi64_si128(sync_epoch);
 789   // epoch[0:31]        = sync_epoch[0:31]
 790   // epoch[32:63]       = sync_epoch[0:31]
 791   // epoch[64:95]       = sync_epoch[0:31]
 792   // epoch[96:127]      = sync_epoch[0:31]
 793   const m128 epoch      = SHUF(epoch1, epoch1, 0, 0, 0, 0);
 794   // load low parts of shadow cell epochs into epoch_vect:
 795   // epoch_vect[0:31]   = shadow0[0:31]
 796   // epoch_vect[32:63]  = shadow0[64:95]
 797   // epoch_vect[64:95]  = shadow1[0:31]
 798   // epoch_vect[96:127] = shadow1[64:95]
 799   const m128 epoch_vect = SHUF(shadow0, shadow1, 0, 2, 0, 2);
 800   // epoch_vect >= sync_epoch?
 801   const m128 epoch_res  = _mm_cmpgt_epi32(epoch_vect, epoch);
 802   // addr_res & epoch_res
 803   const m128 res        = _mm_and_si128(addr_res, epoch_res);
 804   // mask[0] = res[7]
 805   // mask[1] = res[15]
 806   // ...
 807   // mask[15] = res[127]
 808   const int mask        = _mm_movemask_epi8(res);
 809   return mask != 0;
 810 }
 811 #endif
 812
 813 ALWAYS_INLINE
 814 bool ContainsSameAccess(u64 *s, u64 a, u64 sync_epoch, bool is_write) {
 815 #if defined(__SSE3__)
 816   bool res = ContainsSameAccessFast(s, a, sync_epoch, is_write);
 817   // NOTE: this check can fail if the shadow is concurrently mutated
 818   // by other threads. But it still can be useful if you modify
 819   // ContainsSameAccessFast and want to ensure that it's not completely broken.
 820   // DCHECK_EQ(res, ContainsSameAccessSlow(s, a, sync_epoch, is_write));
 821   return res;
 822 #else
 823   return ContainsSameAccessSlow(s, a, sync_epoch, is_write);
 824 #endif
 825 }
 826
 827 ALWAYS_INLINE USED
 828 void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
 829     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic) {
 830   u64 *shadow_mem = (u64*)MemToShadow(addr);
 831   DPrintf2("#%d: MemoryAccess: @%p %p size=%d"
 832       " is_write=%d shadow_mem=%p {%zx, %zx, %zx, %zx}\n",
 833       (int)thr->fast_state.tid(), (void*)pc, (void*)addr,
 834       (int)(1 << kAccessSizeLog), kAccessIsWrite, shadow_mem,
 835       (uptr)shadow_mem[0], (uptr)shadow_mem[1],
 836       (uptr)shadow_mem[2], (uptr)shadow_mem[3]);
 837 #if SANITIZER_DEBUG
 838   if (!IsAppMem(addr)) {
 839     Printf("Access to non app mem %zx\n", addr);
 840     DCHECK(IsAppMem(addr));
 841   }
 842   if (!IsShadowMem((uptr)shadow_mem)) {
 843     Printf("Bad shadow addr %p (%zx)\n", shadow_mem, addr);
 844     DCHECK(IsShadowMem((uptr)shadow_mem));
 845   }
 846 #endif
 847
 848   if (!SANITIZER_GO && !kAccessIsWrite && *shadow_mem == kShadowRodata) {
 849     // Access to .rodata section, no races here.
 850     // Measurements show that it can be 10-20% of all memory accesses.
 851     StatInc(thr, StatMop);
 852     StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 853     StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 854     StatInc(thr, StatMopRodata);
 855     return;
 856   }
 857
 858   FastState fast_state = thr->fast_state;
 859   if (UNLIKELY(fast_state.GetIgnoreBit())) {
 860     StatInc(thr, StatMop);
 861     StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 862     StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 863     StatInc(thr, StatMopIgnored);
 864     return;
 865   }
 866
 867   Shadow cur(fast_state);
 868   cur.SetAddr0AndSizeLog(addr & 7, kAccessSizeLog);
 869   cur.SetWrite(kAccessIsWrite);
 870   cur.SetAtomic(kIsAtomic);
 871
 872   if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(),
 873       thr->fast_synch_epoch, kAccessIsWrite))) {
 874     StatInc(thr, StatMop);
 875     StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 876     StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 877     StatInc(thr, StatMopSame);
 878     return;
 879   }
 880
 881   if (kCollectHistory) {
 882     fast_state.IncrementEpoch();
 883     thr->fast_state = fast_state;
 884     TraceAddEvent(thr, fast_state, EventTypeMop, pc);
 885     cur.IncrementEpoch();
 886   }
 887
 888   MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic,
 889       shadow_mem, cur);
 890 }
 891
 892 // Called by MemoryAccessRange in tsan_rtl_thread.cpp
 893 ALWAYS_INLINE USED
 894 void MemoryAccessImpl(ThreadState *thr, uptr addr,
 895     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
 896     u64 *shadow_mem, Shadow cur) {
 897   if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(),
 898       thr->fast_synch_epoch, kAccessIsWrite))) {
 899     StatInc(thr, StatMop);
 900     StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead);
 901     StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog));
 902     StatInc(thr, StatMopSame);
 903     return;
 904   }
 905
 906   MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic,
 907       shadow_mem, cur);
 908 }
 909
 910 static void MemoryRangeSet(ThreadState *thr, uptr pc, uptr addr, uptr size,
 911                            u64 val) {
 912   (void)thr;
 913   (void)pc;
 914   if (size == 0)
 915     return;
 916   // FIXME: fix me.
 917   uptr offset = addr % kShadowCell;
 918   if (offset) {
 919     offset = kShadowCell - offset;
 920     if (size <= offset)
 921       return;
 922     addr += offset;
 923     size -= offset;
 924   }
 925   DCHECK_EQ(addr % 8, 0);
 926   // If a user passes some insane arguments (memset(0)),
 927   // let it just crash as usual.
 928   if (!IsAppMem(addr) || !IsAppMem(addr + size - 1))
 929     return;
 930   // Don't want to touch lots of shadow memory.
 931   // If a program maps 10MB stack, there is no need reset the whole range.
 932   size = (size + (kShadowCell - 1)) & ~(kShadowCell - 1);
 933   // UnmapOrDie/MmapFixedNoReserve does not work on Windows.
 934   if (SANITIZER_WINDOWS || size < common_flags()->clear_shadow_mmap_threshold) {
 935     u64 *p = (u64*)MemToShadow(addr);
 936     CHECK(IsShadowMem((uptr)p));
 937     CHECK(IsShadowMem((uptr)(p + size * kShadowCnt / kShadowCell - 1)));
 938     // FIXME: may overwrite a part outside the region
 939     for (uptr i = 0; i < size / kShadowCell * kShadowCnt;) {
 940       p[i++] = val;
 941       for (uptr j = 1; j < kShadowCnt; j++)
 942         p[i++] = 0;
 943     }
 944   } else {
 945     // The region is big, reset only beginning and end.
 946     const uptr kPageSize = GetPageSizeCached();
 947     u64 *begin = (u64*)MemToShadow(addr);
 948     u64 *end = begin + size / kShadowCell * kShadowCnt;
 949     u64 *p = begin;
 950     // Set at least first kPageSize/2 to page boundary.
 951     while ((p < begin + kPageSize / kShadowSize / 2) || ((uptr)p % kPageSize)) {
 952       *p++ = val;
 953       for (uptr j = 1; j < kShadowCnt; j++)
 954         *p++ = 0;
 955     }
 956     // Reset middle part.
 957     u64 *p1 = p;
 958     p = RoundDown(end, kPageSize);
 959     UnmapOrDie((void*)p1, (uptr)p - (uptr)p1);
 960     if (!MmapFixedNoReserve((uptr)p1, (uptr)p - (uptr)p1))
 961       Die();
 962     // Set the ending.
 963     while (p < end) {
 964       *p++ = val;
 965       for (uptr j = 1; j < kShadowCnt; j++)
 966         *p++ = 0;
 967     }
 968   }
 969 }
 970
 971 void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 972   MemoryRangeSet(thr, pc, addr, size, 0);
 973 }
 974
 975 void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 976   // Processing more than 1k (4k of shadow) is expensive,
 977   // can cause excessive memory consumption (user does not necessary touch
 978   // the whole range) and most likely unnecessary.
 979   if (size > 1024)
 980     size = 1024;
 981   CHECK_EQ(thr->is_freeing, false);
 982   thr->is_freeing = true;
 983   MemoryAccessRange(thr, pc, addr, size, true);
 984   thr->is_freeing = false;
 985   if (kCollectHistory) {
 986     thr->fast_state.IncrementEpoch();
 987     TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
 988   }
 989   Shadow s(thr->fast_state);
 990   s.ClearIgnoreBit();
 991   s.MarkAsFreed();
 992   s.SetWrite(true);
 993   s.SetAddr0AndSizeLog(0, 3);
 994   MemoryRangeSet(thr, pc, addr, size, s.raw());
 995 }
 996
 997 void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size) {
 998   if (kCollectHistory) {
 999     thr->fast_state.IncrementEpoch();
1000     TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc);
1001   }
1002   Shadow s(thr->fast_state);
1003   s.ClearIgnoreBit();
1004   s.SetWrite(true);
1005   s.SetAddr0AndSizeLog(0, 3);
1006   MemoryRangeSet(thr, pc, addr, size, s.raw());
1007 }
1008
1009 void MemoryRangeImitateWriteOrResetRange(ThreadState *thr, uptr pc, uptr addr,
1010                                          uptr size) {
1011   if (thr->ignore_reads_and_writes == 0)
1012     MemoryRangeImitateWrite(thr, pc, addr, size);
1013   else
1014     MemoryResetRange(thr, pc, addr, size);
1015 }
1016
1017 ALWAYS_INLINE USED
1018 void FuncEntry(ThreadState *thr, uptr pc) {
1019   StatInc(thr, StatFuncEnter);
1020   DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc);
1021   if (kCollectHistory) {
1022     thr->fast_state.IncrementEpoch();
1023     TraceAddEvent(thr, thr->fast_state, EventTypeFuncEnter, pc);
1024   }
1025
1026   // Shadow stack maintenance can be replaced with
1027   // stack unwinding during trace switch (which presumably must be faster).
1028   DCHECK_GE(thr->shadow_stack_pos, thr->shadow_stack);
1029 #if !SANITIZER_GO
1030   DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
1031 #else
1032   if (thr->shadow_stack_pos == thr->shadow_stack_end)
1033     GrowShadowStack(thr);
1034 #endif
1035   thr->shadow_stack_pos[0] = pc;
1036   thr->shadow_stack_pos++;
1037 }
1038
1039 ALWAYS_INLINE USED
1040 void FuncExit(ThreadState *thr) {
1041   StatInc(thr, StatFuncExit);
1042   DPrintf2("#%d: FuncExit\n", (int)thr->fast_state.tid());
1043   if (kCollectHistory) {
1044     thr->fast_state.IncrementEpoch();
1045     TraceAddEvent(thr, thr->fast_state, EventTypeFuncExit, 0);
1046   }
1047
1048   DCHECK_GT(thr->shadow_stack_pos, thr->shadow_stack);
1049 #if !SANITIZER_GO
1050   DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end);
1051 #endif
1052   thr->shadow_stack_pos--;
1053 }
1054
1055 void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack) {
1056   DPrintf("#%d: ThreadIgnoreBegin\n", thr->tid);
1057   thr->ignore_reads_and_writes++;
1058   CHECK_GT(thr->ignore_reads_and_writes, 0);
1059   thr->fast_state.SetIgnoreBit();
1060 #if !SANITIZER_GO
1061   if (save_stack && !ctx->after_multithreaded_fork)
1062     thr->mop_ignore_set.Add(CurrentStackId(thr, pc));
1063 #endif
1064 }
1065
1066 void ThreadIgnoreEnd(ThreadState *thr, uptr pc) {
1067   DPrintf("#%d: ThreadIgnoreEnd\n", thr->tid);
1068   CHECK_GT(thr->ignore_reads_and_writes, 0);
1069   thr->ignore_reads_and_writes--;
1070   if (thr->ignore_reads_and_writes == 0) {
1071     thr->fast_state.ClearIgnoreBit();
1072 #if !SANITIZER_GO
1073     thr->mop_ignore_set.Reset();
1074 #endif
1075   }
1076 }
1077
1078 #if !SANITIZER_GO
1079 extern "C" SANITIZER_INTERFACE_ATTRIBUTE
1080 uptr __tsan_testonly_shadow_stack_current_size() {
1081   ThreadState *thr = cur_thread();
1082   return thr->shadow_stack_pos - thr->shadow_stack;
1083 }
1084 #endif
1085
1086 void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc, bool save_stack) {
1087   DPrintf("#%d: ThreadIgnoreSyncBegin\n", thr->tid);
1088   thr->ignore_sync++;
1089   CHECK_GT(thr->ignore_sync, 0);
1090 #if !SANITIZER_GO
1091   if (save_stack && !ctx->after_multithreaded_fork)
1092     thr->sync_ignore_set.Add(CurrentStackId(thr, pc));
1093 #endif
1094 }
1095
1096 void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc) {
1097   DPrintf("#%d: ThreadIgnoreSyncEnd\n", thr->tid);
1098   CHECK_GT(thr->ignore_sync, 0);
1099   thr->ignore_sync--;
1100 #if !SANITIZER_GO
1101   if (thr->ignore_sync == 0)
1102     thr->sync_ignore_set.Reset();
1103 #endif
1104 }
1105
1106 bool MD5Hash::operator==(const MD5Hash &other) const {
1107   return hash[0] == other.hash[0] && hash[1] == other.hash[1];
1108 }
1109
1110 #if SANITIZER_DEBUG
1111 void build_consistency_debug() {}
1112 #else
1113 void build_consistency_release() {}
1114 #endif
1115
1116 #if TSAN_COLLECT_STATS
1117 void build_consistency_stats() {}
1118 #else
1119 void build_consistency_nostats() {}
1120 #endif
1121
1122 }  // namespace __tsan
1123
1124 #if !SANITIZER_GO
1125 // Must be included in this file to make sure everything is inlined.
1126 #include "tsan_interface_inl.h"
1127 #endif