tsan_rtl.h 28.1 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893
//===-- tsan_rtl.h ----------------------------------------------*- C++ -*-===//
//
// 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 internal TSan header file.
//
// Ground rules:
//   - C++ run-time should not be used (static CTORs, RTTI, exceptions, static
//     function-scope locals)
//   - All functions/classes/etc reside in namespace __tsan, except for those
//     declared in tsan_interface.h.
//   - Platform-specific files should be used instead of ifdefs (*).
//   - No system headers included in header files (*).
//   - Platform specific headres included only into platform-specific files (*).
//
//  (*) Except when inlining is critical for performance.
//===----------------------------------------------------------------------===//

#ifndef TSAN_RTL_H
#define TSAN_RTL_H

#include "sanitizer_common/sanitizer_allocator.h"
#include "sanitizer_common/sanitizer_allocator_internal.h"
#include "sanitizer_common/sanitizer_asm.h"
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_deadlock_detector_interface.h"
#include "sanitizer_common/sanitizer_libignore.h"
#include "sanitizer_common/sanitizer_suppressions.h"
#include "sanitizer_common/sanitizer_thread_registry.h"
#include "sanitizer_common/sanitizer_vector.h"
#include "tsan_clock.h"
#include "tsan_defs.h"
#include "tsan_flags.h"
#include "tsan_mman.h"
#include "tsan_sync.h"
#include "tsan_trace.h"
#include "tsan_report.h"
#include "tsan_platform.h"
#include "tsan_mutexset.h"
#include "tsan_ignoreset.h"
#include "tsan_stack_trace.h"

#if SANITIZER_WORDSIZE != 64
# error "ThreadSanitizer is supported only on 64-bit platforms"
#endif

namespace __tsan {

#if !SANITIZER_GO
struct MapUnmapCallback;
#if defined(__mips64) || defined(__aarch64__) || defined(__powerpc__)

struct AP32 {
  static const uptr kSpaceBeg = 0;
  static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
  static const uptr kMetadataSize = 0;
  typedef __sanitizer::CompactSizeClassMap SizeClassMap;
  static const uptr kRegionSizeLog = 20;
  using AddressSpaceView = LocalAddressSpaceView;
  typedef __tsan::MapUnmapCallback MapUnmapCallback;
  static const uptr kFlags = 0;
};
typedef SizeClassAllocator32<AP32> PrimaryAllocator;
#else
struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
  static const uptr kSpaceBeg = Mapping::kHeapMemBeg;
  static const uptr kSpaceSize = Mapping::kHeapMemEnd - Mapping::kHeapMemBeg;
  static const uptr kMetadataSize = 0;
  typedef DefaultSizeClassMap SizeClassMap;
  typedef __tsan::MapUnmapCallback MapUnmapCallback;
  static const uptr kFlags = 0;
  using AddressSpaceView = LocalAddressSpaceView;
};
typedef SizeClassAllocator64<AP64> PrimaryAllocator;
#endif
typedef CombinedAllocator<PrimaryAllocator> Allocator;
typedef Allocator::AllocatorCache AllocatorCache;
Allocator *allocator();
#endif

void TsanCheckFailed(const char *file, int line, const char *cond,
                     u64 v1, u64 v2);

const u64 kShadowRodata = (u64)-1;  // .rodata shadow marker

// FastState (from most significant bit):
//   ignore          : 1
//   tid             : kTidBits
//   unused          : -
//   history_size    : 3
//   epoch           : kClkBits
class FastState {
 public:
  FastState(u64 tid, u64 epoch) {
    x_ = tid << kTidShift;
    x_ |= epoch;
    DCHECK_EQ(tid, this->tid());
    DCHECK_EQ(epoch, this->epoch());
    DCHECK_EQ(GetIgnoreBit(), false);
  }

  explicit FastState(u64 x)
      : x_(x) {
  }

  u64 raw() const {
    return x_;
  }

  u64 tid() const {
    u64 res = (x_ & ~kIgnoreBit) >> kTidShift;
    return res;
  }

  u64 TidWithIgnore() const {
    u64 res = x_ >> kTidShift;
    return res;
  }

  u64 epoch() const {
    u64 res = x_ & ((1ull << kClkBits) - 1);
    return res;
  }

  void IncrementEpoch() {
    u64 old_epoch = epoch();
    x_ += 1;
    DCHECK_EQ(old_epoch + 1, epoch());
    (void)old_epoch;
  }

  void SetIgnoreBit() { x_ |= kIgnoreBit; }
  void ClearIgnoreBit() { x_ &= ~kIgnoreBit; }
  bool GetIgnoreBit() const { return (s64)x_ < 0; }

  void SetHistorySize(int hs) {
    CHECK_GE(hs, 0);
    CHECK_LE(hs, 7);
    x_ = (x_ & ~(kHistoryMask << kHistoryShift)) | (u64(hs) << kHistoryShift);
  }

  ALWAYS_INLINE
  int GetHistorySize() const {
    return (int)((x_ >> kHistoryShift) & kHistoryMask);
  }

  void ClearHistorySize() {
    SetHistorySize(0);
  }

  ALWAYS_INLINE
  u64 GetTracePos() const {
    const int hs = GetHistorySize();
    // When hs == 0, the trace consists of 2 parts.
    const u64 mask = (1ull << (kTracePartSizeBits + hs + 1)) - 1;
    return epoch() & mask;
  }

 private:
  friend class Shadow;
  static const int kTidShift = 64 - kTidBits - 1;
  static const u64 kIgnoreBit = 1ull << 63;
  static const u64 kFreedBit = 1ull << 63;
  static const u64 kHistoryShift = kClkBits;
  static const u64 kHistoryMask = 7;
  u64 x_;
};

// Shadow (from most significant bit):
//   freed           : 1
//   tid             : kTidBits
//   is_atomic       : 1
//   is_read         : 1
//   size_log        : 2
//   addr0           : 3
//   epoch           : kClkBits
class Shadow : public FastState {
 public:
  explicit Shadow(u64 x)
      : FastState(x) {
  }

  explicit Shadow(const FastState &s)
      : FastState(s.x_) {
    ClearHistorySize();
  }

  void SetAddr0AndSizeLog(u64 addr0, unsigned kAccessSizeLog) {
    DCHECK_EQ((x_ >> kClkBits) & 31, 0);
    DCHECK_LE(addr0, 7);
    DCHECK_LE(kAccessSizeLog, 3);
    x_ |= ((kAccessSizeLog << 3) | addr0) << kClkBits;
    DCHECK_EQ(kAccessSizeLog, size_log());
    DCHECK_EQ(addr0, this->addr0());
  }

  void SetWrite(unsigned kAccessIsWrite) {
    DCHECK_EQ(x_ & kReadBit, 0);
    if (!kAccessIsWrite)
      x_ |= kReadBit;
    DCHECK_EQ(kAccessIsWrite, IsWrite());
  }

  void SetAtomic(bool kIsAtomic) {
    DCHECK(!IsAtomic());
    if (kIsAtomic)
      x_ |= kAtomicBit;
    DCHECK_EQ(IsAtomic(), kIsAtomic);
  }

  bool IsAtomic() const {
    return x_ & kAtomicBit;
  }

  bool IsZero() const {
    return x_ == 0;
  }

  static inline bool TidsAreEqual(const Shadow s1, const Shadow s2) {
    u64 shifted_xor = (s1.x_ ^ s2.x_) >> kTidShift;
    DCHECK_EQ(shifted_xor == 0, s1.TidWithIgnore() == s2.TidWithIgnore());
    return shifted_xor == 0;
  }

  static ALWAYS_INLINE
  bool Addr0AndSizeAreEqual(const Shadow s1, const Shadow s2) {
    u64 masked_xor = ((s1.x_ ^ s2.x_) >> kClkBits) & 31;
    return masked_xor == 0;
  }

  static ALWAYS_INLINE bool TwoRangesIntersect(Shadow s1, Shadow s2,
      unsigned kS2AccessSize) {
    bool res = false;
    u64 diff = s1.addr0() - s2.addr0();
    if ((s64)diff < 0) {  // s1.addr0 < s2.addr0
      // if (s1.addr0() + size1) > s2.addr0()) return true;
      if (s1.size() > -diff)
        res = true;
    } else {
      // if (s2.addr0() + kS2AccessSize > s1.addr0()) return true;
      if (kS2AccessSize > diff)
        res = true;
    }
    DCHECK_EQ(res, TwoRangesIntersectSlow(s1, s2));
    DCHECK_EQ(res, TwoRangesIntersectSlow(s2, s1));
    return res;
  }

  u64 ALWAYS_INLINE addr0() const { return (x_ >> kClkBits) & 7; }
  u64 ALWAYS_INLINE size() const { return 1ull << size_log(); }
  bool ALWAYS_INLINE IsWrite() const { return !IsRead(); }
  bool ALWAYS_INLINE IsRead() const { return x_ & kReadBit; }

  // The idea behind the freed bit is as follows.
  // When the memory is freed (or otherwise unaccessible) we write to the shadow
  // values with tid/epoch related to the free and the freed bit set.
  // During memory accesses processing the freed bit is considered
  // as msb of tid. So any access races with shadow with freed bit set
  // (it is as if write from a thread with which we never synchronized before).
  // This allows us to detect accesses to freed memory w/o additional
  // overheads in memory access processing and at the same time restore
  // tid/epoch of free.
  void MarkAsFreed() {
     x_ |= kFreedBit;
  }

  bool IsFreed() const {
    return x_ & kFreedBit;
  }

  bool GetFreedAndReset() {
    bool res = x_ & kFreedBit;
    x_ &= ~kFreedBit;
    return res;
  }

  bool ALWAYS_INLINE IsBothReadsOrAtomic(bool kIsWrite, bool kIsAtomic) const {
    bool v = x_ & ((u64(kIsWrite ^ 1) << kReadShift)
        | (u64(kIsAtomic) << kAtomicShift));
    DCHECK_EQ(v, (!IsWrite() && !kIsWrite) || (IsAtomic() && kIsAtomic));
    return v;
  }

  bool ALWAYS_INLINE IsRWNotWeaker(bool kIsWrite, bool kIsAtomic) const {
    bool v = ((x_ >> kReadShift) & 3)
        <= u64((kIsWrite ^ 1) | (kIsAtomic << 1));
    DCHECK_EQ(v, (IsAtomic() < kIsAtomic) ||
        (IsAtomic() == kIsAtomic && !IsWrite() <= !kIsWrite));
    return v;
  }

  bool ALWAYS_INLINE IsRWWeakerOrEqual(bool kIsWrite, bool kIsAtomic) const {
    bool v = ((x_ >> kReadShift) & 3)
        >= u64((kIsWrite ^ 1) | (kIsAtomic << 1));
    DCHECK_EQ(v, (IsAtomic() > kIsAtomic) ||
        (IsAtomic() == kIsAtomic && !IsWrite() >= !kIsWrite));
    return v;
  }

 private:
  static const u64 kReadShift   = 5 + kClkBits;
  static const u64 kReadBit     = 1ull << kReadShift;
  static const u64 kAtomicShift = 6 + kClkBits;
  static const u64 kAtomicBit   = 1ull << kAtomicShift;

  u64 size_log() const { return (x_ >> (3 + kClkBits)) & 3; }

  static bool TwoRangesIntersectSlow(const Shadow s1, const Shadow s2) {
    if (s1.addr0() == s2.addr0()) return true;
    if (s1.addr0() < s2.addr0() && s1.addr0() + s1.size() > s2.addr0())
      return true;
    if (s2.addr0() < s1.addr0() && s2.addr0() + s2.size() > s1.addr0())
      return true;
    return false;
  }
};

struct ThreadSignalContext;

struct JmpBuf {
  uptr sp;
  int int_signal_send;
  bool in_blocking_func;
  uptr in_signal_handler;
  uptr *shadow_stack_pos;
};

// A Processor represents a physical thread, or a P for Go.
// It is used to store internal resources like allocate cache, and does not
// participate in race-detection logic (invisible to end user).
// In C++ it is tied to an OS thread just like ThreadState, however ideally
// it should be tied to a CPU (this way we will have fewer allocator caches).
// In Go it is tied to a P, so there are significantly fewer Processor's than
// ThreadState's (which are tied to Gs).
// A ThreadState must be wired with a Processor to handle events.
struct Processor {
  ThreadState *thr; // currently wired thread, or nullptr
#if !SANITIZER_GO
  AllocatorCache alloc_cache;
  InternalAllocatorCache internal_alloc_cache;
#endif
  DenseSlabAllocCache block_cache;
  DenseSlabAllocCache sync_cache;
  DenseSlabAllocCache clock_cache;
  DDPhysicalThread *dd_pt;
};

#if !SANITIZER_GO
// ScopedGlobalProcessor temporary setups a global processor for the current
// thread, if it does not have one. Intended for interceptors that can run
// at the very thread end, when we already destroyed the thread processor.
struct ScopedGlobalProcessor {
  ScopedGlobalProcessor();
  ~ScopedGlobalProcessor();
};
#endif

// This struct is stored in TLS.
struct ThreadState {
  FastState fast_state;
  // Synch epoch represents the threads's epoch before the last synchronization
  // action. It allows to reduce number of shadow state updates.
  // For example, fast_synch_epoch=100, last write to addr X was at epoch=150,
  // if we are processing write to X from the same thread at epoch=200,
  // we do nothing, because both writes happen in the same 'synch epoch'.
  // That is, if another memory access does not race with the former write,
  // it does not race with the latter as well.
  // QUESTION: can we can squeeze this into ThreadState::Fast?
  // E.g. ThreadState::Fast is a 44-bit, 32 are taken by synch_epoch and 12 are
  // taken by epoch between synchs.
  // This way we can save one load from tls.
  u64 fast_synch_epoch;
  // Technically `current` should be a separate THREADLOCAL variable;
  // but it is placed here in order to share cache line with previous fields.
  ThreadState* current;
  // This is a slow path flag. On fast path, fast_state.GetIgnoreBit() is read.
  // We do not distinguish beteween ignoring reads and writes
  // for better performance.
  int ignore_reads_and_writes;
  int ignore_sync;
  int suppress_reports;
  // Go does not support ignores.
#if !SANITIZER_GO
  IgnoreSet mop_ignore_set;
  IgnoreSet sync_ignore_set;
#endif
  // C/C++ uses fixed size shadow stack embed into Trace.
  // Go uses malloc-allocated shadow stack with dynamic size.
  uptr *shadow_stack;
  uptr *shadow_stack_end;
  uptr *shadow_stack_pos;
  u64 *racy_shadow_addr;
  u64 racy_state[2];
  MutexSet mset;
  ThreadClock clock;
#if !SANITIZER_GO
  Vector<JmpBuf> jmp_bufs;
  int ignore_interceptors;
#endif
#if TSAN_COLLECT_STATS
  u64 stat[StatCnt];
#endif
  const int tid;
  const int unique_id;
  bool in_symbolizer;
  bool in_ignored_lib;
  bool is_inited;
  bool is_dead;
  bool is_freeing;
  bool is_vptr_access;
  const uptr stk_addr;
  const uptr stk_size;
  const uptr tls_addr;
  const uptr tls_size;
  ThreadContext *tctx;

#if SANITIZER_DEBUG && !SANITIZER_GO
  InternalDeadlockDetector internal_deadlock_detector;
#endif
  DDLogicalThread *dd_lt;

  // Current wired Processor, or nullptr. Required to handle any events.
  Processor *proc1;
#if !SANITIZER_GO
  Processor *proc() { return proc1; }
#else
  Processor *proc();
#endif

  atomic_uintptr_t in_signal_handler;
  ThreadSignalContext *signal_ctx;

#if !SANITIZER_GO
  u32 last_sleep_stack_id;
  ThreadClock last_sleep_clock;
#endif

  // Set in regions of runtime that must be signal-safe and fork-safe.
  // If set, malloc must not be called.
  int nomalloc;

  const ReportDesc *current_report;

  explicit 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);
};

#if !SANITIZER_GO
#if SANITIZER_MAC || SANITIZER_ANDROID
ThreadState *cur_thread();
void set_cur_thread(ThreadState *thr);
void cur_thread_finalize();
inline void cur_thread_init() { }
#else
__attribute__((tls_model("initial-exec")))
extern THREADLOCAL char cur_thread_placeholder[];
inline ThreadState *cur_thread() {
  return reinterpret_cast<ThreadState *>(cur_thread_placeholder)->current;
}
inline void cur_thread_init() {
  ThreadState *thr = reinterpret_cast<ThreadState *>(cur_thread_placeholder);
  if (UNLIKELY(!thr->current))
    thr->current = thr;
}
inline void set_cur_thread(ThreadState *thr) {
  reinterpret_cast<ThreadState *>(cur_thread_placeholder)->current = thr;
}
inline void cur_thread_finalize() { }
#endif  // SANITIZER_MAC || SANITIZER_ANDROID
#endif  // SANITIZER_GO

class ThreadContext : public ThreadContextBase {
 public:
  explicit ThreadContext(int tid);
  ~ThreadContext();
  ThreadState *thr;
  u32 creation_stack_id;
  SyncClock sync;
  // Epoch at which the thread had started.
  // If we see an event from the thread stamped by an older epoch,
  // the event is from a dead thread that shared tid with this thread.
  u64 epoch0;
  u64 epoch1;

  // Override superclass callbacks.
  void OnDead() override;
  void OnJoined(void *arg) override;
  void OnFinished() override;
  void OnStarted(void *arg) override;
  void OnCreated(void *arg) override;
  void OnReset() override;
  void OnDetached(void *arg) override;
};

struct RacyStacks {
  MD5Hash hash[2];
  bool operator==(const RacyStacks &other) const {
    if (hash[0] == other.hash[0] && hash[1] == other.hash[1])
      return true;
    if (hash[0] == other.hash[1] && hash[1] == other.hash[0])
      return true;
    return false;
  }
};

struct RacyAddress {
  uptr addr_min;
  uptr addr_max;
};

struct FiredSuppression {
  ReportType type;
  uptr pc_or_addr;
  Suppression *supp;
};

struct Context {
  Context();

  bool initialized;
#if !SANITIZER_GO
  bool after_multithreaded_fork;
#endif

  MetaMap metamap;

  Mutex report_mtx;
  int nreported;
  int nmissed_expected;
  atomic_uint64_t last_symbolize_time_ns;

  void *background_thread;
  atomic_uint32_t stop_background_thread;

  ThreadRegistry *thread_registry;

  Mutex racy_mtx;
  Vector<RacyStacks> racy_stacks;
  Vector<RacyAddress> racy_addresses;
  // Number of fired suppressions may be large enough.
  Mutex fired_suppressions_mtx;
  InternalMmapVector<FiredSuppression> fired_suppressions;
  DDetector *dd;

  ClockAlloc clock_alloc;

  Flags flags;

  u64 stat[StatCnt];
  u64 int_alloc_cnt[MBlockTypeCount];
  u64 int_alloc_siz[MBlockTypeCount];
};

extern Context *ctx;  // The one and the only global runtime context.

ALWAYS_INLINE Flags *flags() {
  return &ctx->flags;
}

struct ScopedIgnoreInterceptors {
  ScopedIgnoreInterceptors() {
#if !SANITIZER_GO
    cur_thread()->ignore_interceptors++;
#endif
  }

  ~ScopedIgnoreInterceptors() {
#if !SANITIZER_GO
    cur_thread()->ignore_interceptors--;
#endif
  }
};

const char *GetObjectTypeFromTag(uptr tag);
const char *GetReportHeaderFromTag(uptr tag);
uptr TagFromShadowStackFrame(uptr pc);

class ScopedReportBase {
 public:
  void AddMemoryAccess(uptr addr, uptr external_tag, Shadow s, StackTrace stack,
                       const MutexSet *mset);
  void AddStack(StackTrace stack, bool suppressable = false);
  void AddThread(const ThreadContext *tctx, bool suppressable = false);
  void AddThread(int unique_tid, bool suppressable = false);
  void AddUniqueTid(int unique_tid);
  void AddMutex(const SyncVar *s);
  u64 AddMutex(u64 id);
  void AddLocation(uptr addr, uptr size);
  void AddSleep(u32 stack_id);
  void SetCount(int count);

  const ReportDesc *GetReport() const;

 protected:
  ScopedReportBase(ReportType typ, uptr tag);
  ~ScopedReportBase();

 private:
  ReportDesc *rep_;
  // Symbolizer makes lots of intercepted calls. If we try to process them,
  // at best it will cause deadlocks on internal mutexes.
  ScopedIgnoreInterceptors ignore_interceptors_;

  void AddDeadMutex(u64 id);

  ScopedReportBase(const ScopedReportBase &) = delete;
  void operator=(const ScopedReportBase &) = delete;
};

class ScopedReport : public ScopedReportBase {
 public:
  explicit ScopedReport(ReportType typ, uptr tag = kExternalTagNone);
  ~ScopedReport();

 private:
  ScopedErrorReportLock lock_;
};

ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack);
void RestoreStack(int tid, const u64 epoch, VarSizeStackTrace *stk,
                  MutexSet *mset, uptr *tag = nullptr);

// The stack could look like:
//   <start> | <main> | <foo> | tag | <bar>
// This will extract the tag and keep:
//   <start> | <main> | <foo> | <bar>
template<typename StackTraceTy>
void ExtractTagFromStack(StackTraceTy *stack, uptr *tag = nullptr) {
  if (stack->size < 2) return;
  uptr possible_tag_pc = stack->trace[stack->size - 2];
  uptr possible_tag = TagFromShadowStackFrame(possible_tag_pc);
  if (possible_tag == kExternalTagNone) return;
  stack->trace_buffer[stack->size - 2] = stack->trace_buffer[stack->size - 1];
  stack->size -= 1;
  if (tag) *tag = possible_tag;
}

template<typename StackTraceTy>
void ObtainCurrentStack(ThreadState *thr, uptr toppc, StackTraceTy *stack,
                        uptr *tag = nullptr) {
  uptr size = thr->shadow_stack_pos - thr->shadow_stack;
  uptr start = 0;
  if (size + !!toppc > kStackTraceMax) {
    start = size + !!toppc - kStackTraceMax;
    size = kStackTraceMax - !!toppc;
  }
  stack->Init(&thr->shadow_stack[start], size, toppc);
  ExtractTagFromStack(stack, tag);
}

#define GET_STACK_TRACE_FATAL(thr, pc) \
  VarSizeStackTrace stack; \
  ObtainCurrentStack(thr, pc, &stack); \
  stack.ReverseOrder();

#if TSAN_COLLECT_STATS
void StatAggregate(u64 *dst, u64 *src);
void StatOutput(u64 *stat);
#endif

void ALWAYS_INLINE StatInc(ThreadState *thr, StatType typ, u64 n = 1) {
#if TSAN_COLLECT_STATS
  thr->stat[typ] += n;
#endif
}
void ALWAYS_INLINE StatSet(ThreadState *thr, StatType typ, u64 n) {
#if TSAN_COLLECT_STATS
  thr->stat[typ] = n;
#endif
}

void MapShadow(uptr addr, uptr size);
void MapThreadTrace(uptr addr, uptr size, const char *name);
void DontNeedShadowFor(uptr addr, uptr size);
void UnmapShadow(ThreadState *thr, uptr addr, uptr size);
void InitializeShadowMemory();
void InitializeInterceptors();
void InitializeLibIgnore();
void InitializeDynamicAnnotations();

void ForkBefore(ThreadState *thr, uptr pc);
void ForkParentAfter(ThreadState *thr, uptr pc);
void ForkChildAfter(ThreadState *thr, uptr pc);

void ReportRace(ThreadState *thr);
bool OutputReport(ThreadState *thr, const ScopedReport &srep);
bool IsFiredSuppression(Context *ctx, ReportType type, StackTrace trace);
bool IsExpectedReport(uptr addr, uptr size);
void PrintMatchedBenignRaces();

#if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 1
# define DPrintf Printf
#else
# define DPrintf(...)
#endif

#if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 2
# define DPrintf2 Printf
#else
# define DPrintf2(...)
#endif

u32 CurrentStackId(ThreadState *thr, uptr pc);
ReportStack *SymbolizeStackId(u32 stack_id);
void PrintCurrentStack(ThreadState *thr, uptr pc);
void PrintCurrentStackSlow(uptr pc);  // uses libunwind

void Initialize(ThreadState *thr);
void MaybeSpawnBackgroundThread();
int Finalize(ThreadState *thr);

void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write);
void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write);

void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
    int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic);
void MemoryAccessImpl(ThreadState *thr, uptr addr,
    int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
    u64 *shadow_mem, Shadow cur);
void MemoryAccessRange(ThreadState *thr, uptr pc, uptr addr,
    uptr size, bool is_write);
void MemoryAccessRangeStep(ThreadState *thr, uptr pc, uptr addr,
    uptr size, uptr step, bool is_write);
void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr,
    int size, bool kAccessIsWrite, bool kIsAtomic);

const int kSizeLog1 = 0;
const int kSizeLog2 = 1;
const int kSizeLog4 = 2;
const int kSizeLog8 = 3;

void ALWAYS_INLINE MemoryRead(ThreadState *thr, uptr pc,
                                     uptr addr, int kAccessSizeLog) {
  MemoryAccess(thr, pc, addr, kAccessSizeLog, false, false);
}

void ALWAYS_INLINE MemoryWrite(ThreadState *thr, uptr pc,
                                      uptr addr, int kAccessSizeLog) {
  MemoryAccess(thr, pc, addr, kAccessSizeLog, true, false);
}

void ALWAYS_INLINE MemoryReadAtomic(ThreadState *thr, uptr pc,
                                           uptr addr, int kAccessSizeLog) {
  MemoryAccess(thr, pc, addr, kAccessSizeLog, false, true);
}

void ALWAYS_INLINE MemoryWriteAtomic(ThreadState *thr, uptr pc,
                                            uptr addr, int kAccessSizeLog) {
  MemoryAccess(thr, pc, addr, kAccessSizeLog, true, true);
}

void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size);
void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size);
void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size);
void MemoryRangeImitateWriteOrResetRange(ThreadState *thr, uptr pc, uptr addr,
                                         uptr size);

void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack = true);
void ThreadIgnoreEnd(ThreadState *thr, uptr pc);
void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc, bool save_stack = true);
void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc);

void FuncEntry(ThreadState *thr, uptr pc);
void FuncExit(ThreadState *thr);

int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached);
void ThreadStart(ThreadState *thr, int tid, tid_t os_id,
                 ThreadType thread_type);
void ThreadFinish(ThreadState *thr);
int ThreadConsumeTid(ThreadState *thr, uptr pc, uptr uid);
void ThreadJoin(ThreadState *thr, uptr pc, int tid);
void ThreadDetach(ThreadState *thr, uptr pc, int tid);
void ThreadFinalize(ThreadState *thr);
void ThreadSetName(ThreadState *thr, const char *name);
int ThreadCount(ThreadState *thr);
void ProcessPendingSignals(ThreadState *thr);
void ThreadNotJoined(ThreadState *thr, uptr pc, int tid, uptr uid);

Processor *ProcCreate();
void ProcDestroy(Processor *proc);
void ProcWire(Processor *proc, ThreadState *thr);
void ProcUnwire(Processor *proc, ThreadState *thr);

// Note: the parameter is called flagz, because flags is already taken
// by the global function that returns flags.
void MutexCreate(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexDestroy(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexPreLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexPostLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0,
    int rec = 1);
int  MutexUnlock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexPreReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexPostReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
void MutexReadUnlock(ThreadState *thr, uptr pc, uptr addr);
void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr);
void MutexRepair(ThreadState *thr, uptr pc, uptr addr);  // call on EOWNERDEAD
void MutexInvalidAccess(ThreadState *thr, uptr pc, uptr addr);

void Acquire(ThreadState *thr, uptr pc, uptr addr);
// AcquireGlobal synchronizes the current thread with all other threads.
// In terms of happens-before relation, it draws a HB edge from all threads
// (where they happen to execute right now) to the current thread. We use it to
// handle Go finalizers. Namely, finalizer goroutine executes AcquireGlobal
// right before executing finalizers. This provides a coarse, but simple
// approximation of the actual required synchronization.
void AcquireGlobal(ThreadState *thr, uptr pc);
void Release(ThreadState *thr, uptr pc, uptr addr);
void ReleaseStoreAcquire(ThreadState *thr, uptr pc, uptr addr);
void ReleaseStore(ThreadState *thr, uptr pc, uptr addr);
void AfterSleep(ThreadState *thr, uptr pc);
void AcquireImpl(ThreadState *thr, uptr pc, SyncClock *c);
void ReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c);
void ReleaseStoreAcquireImpl(ThreadState *thr, uptr pc, SyncClock *c);
void ReleaseStoreImpl(ThreadState *thr, uptr pc, SyncClock *c);
void AcquireReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c);

// The hacky call uses custom calling convention and an assembly thunk.
// It is considerably faster that a normal call for the caller
// if it is not executed (it is intended for slow paths from hot functions).
// The trick is that the call preserves all registers and the compiler
// does not treat it as a call.
// If it does not work for you, use normal call.
#if !SANITIZER_DEBUG && defined(__x86_64__) && !SANITIZER_MAC
// The caller may not create the stack frame for itself at all,
// so we create a reserve stack frame for it (1024b must be enough).
#define HACKY_CALL(f) \
  __asm__ __volatile__("sub $1024, %%rsp;" \
                       CFI_INL_ADJUST_CFA_OFFSET(1024) \
                       ".hidden " #f "_thunk;" \
                       "call " #f "_thunk;" \
                       "add $1024, %%rsp;" \
                       CFI_INL_ADJUST_CFA_OFFSET(-1024) \
                       ::: "memory", "cc");
#else
#define HACKY_CALL(f) f()
#endif

void TraceSwitch(ThreadState *thr);
uptr TraceTopPC(ThreadState *thr);
uptr TraceSize();
uptr TraceParts();
Trace *ThreadTrace(int tid);

extern "C" void __tsan_trace_switch();
void ALWAYS_INLINE TraceAddEvent(ThreadState *thr, FastState fs,
                                        EventType typ, u64 addr) {
  if (!kCollectHistory)
    return;
  DCHECK_GE((int)typ, 0);
  DCHECK_LE((int)typ, 7);
  DCHECK_EQ(GetLsb(addr, kEventPCBits), addr);
  StatInc(thr, StatEvents);
  u64 pos = fs.GetTracePos();
  if (UNLIKELY((pos % kTracePartSize) == 0)) {
#if !SANITIZER_GO
    HACKY_CALL(__tsan_trace_switch);
#else
    TraceSwitch(thr);
#endif
  }
  Event *trace = (Event*)GetThreadTrace(fs.tid());
  Event *evp = &trace[pos];
  Event ev = (u64)addr | ((u64)typ << kEventPCBits);
  *evp = ev;
}

#if !SANITIZER_GO
uptr ALWAYS_INLINE HeapEnd() {
  return HeapMemEnd() + PrimaryAllocator::AdditionalSize();
}
#endif

ThreadState *FiberCreate(ThreadState *thr, uptr pc, unsigned flags);
void FiberDestroy(ThreadState *thr, uptr pc, ThreadState *fiber);
void FiberSwitch(ThreadState *thr, uptr pc, ThreadState *fiber, unsigned flags);

// These need to match __tsan_switch_to_fiber_* flags defined in
// tsan_interface.h. See documentation there as well.
enum FiberSwitchFlags {
  FiberSwitchFlagNoSync = 1 << 0, // __tsan_switch_to_fiber_no_sync
};

}  // namespace __tsan

#endif  // TSAN_RTL_H