src/compiler-rt/lib/xray/xray_emulate_tsc.h

   1 //===-- xray_emulate_tsc.h --------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file is a part of XRay, a dynamic runtime instrumentation system.
  11 //
  12 //===----------------------------------------------------------------------===//
  13 #ifndef XRAY_EMULATE_TSC_H
  14 #define XRAY_EMULATE_TSC_H
  15
  16 #include "sanitizer_common/sanitizer_common.h"
  17 #include "sanitizer_common/sanitizer_internal_defs.h"
  18 #include "xray_defs.h"
  19 #include <cerrno>
  20 #include <cstdint>
  21 #include <time.h>
  22
  23 namespace __xray {
  24
  25 static constexpr uint64_t NanosecondsPerSecond = 1000ULL * 1000 * 1000;
  26
  27 ALWAYS_INLINE uint64_t readTSC(uint8_t &CPU) XRAY_NEVER_INSTRUMENT {
  28   timespec TS;
  29   int result = clock_gettime(CLOCK_REALTIME, &TS);
  30   if (result != 0) {
  31     Report("clock_gettime(2) returned %d, errno=%d.", result, int(errno));
  32     TS.tv_sec = 0;
  33     TS.tv_nsec = 0;
  34   }
  35   CPU = 0;
  36   return TS.tv_sec * NanosecondsPerSecond + TS.tv_nsec;
  37 }
  38 }
  39
  40 #endif // XRAY_EMULATE_TSC_H