libsanitizer/tsan/tsan_vector_clock.h

   1 //===-- tsan_vector_clock.h -------------------------------------*- C++ -*-===//
   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 //===----------------------------------------------------------------------===//
  12 #ifndef TSAN_VECTOR_CLOCK_H
  13 #define TSAN_VECTOR_CLOCK_H
  14
  15 #include "tsan_defs.h"
  16
  17 namespace __tsan {
  18
  19 // Fixed-size vector clock, used both for threads and sync objects.
  20 class VectorClock {
  21  public:
  22   VectorClock();
  23
  24   Epoch Get(Sid sid) const;
  25   void Set(Sid sid, Epoch v);
  26
  27   void Reset();
  28   void Acquire(const VectorClock* src);
  29   void Release(VectorClock** dstp) const;
  30   void ReleaseStore(VectorClock** dstp) const;
  31   void ReleaseStoreAcquire(VectorClock** dstp);
  32   void ReleaseAcquire(VectorClock** dstp);
  33
  34   VectorClock& operator=(const VectorClock& other);
  35
  36  private:
  37   Epoch clk_[kThreadSlotCount] VECTOR_ALIGNED;
  38 };
  39
  40 ALWAYS_INLINE Epoch VectorClock::Get(Sid sid) const {
  41   return clk_[static_cast<u8>(sid)];
  42 }
  43
  44 ALWAYS_INLINE void VectorClock::Set(Sid sid, Epoch v) {
  45   DCHECK_GE(v, clk_[static_cast<u8>(sid)]);
  46   clk_[static_cast<u8>(sid)] = v;
  47 }
  48
  49 }  // namespace __tsan
  50
  51 #endif  // TSAN_VECTOR_CLOCK_H