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Diffstat (limited to 'contrib/llvm-project/compiler-rt/lib/xray/xray_tsc.h')
-rw-r--r-- | contrib/llvm-project/compiler-rt/lib/xray/xray_tsc.h | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/xray/xray_tsc.h b/contrib/llvm-project/compiler-rt/lib/xray/xray_tsc.h new file mode 100644 index 000000000000..e1cafe1bf11d --- /dev/null +++ b/contrib/llvm-project/compiler-rt/lib/xray/xray_tsc.h @@ -0,0 +1,91 @@ +//===-- xray_tsc.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 XRay, a dynamic runtime instrumentation system. +// +//===----------------------------------------------------------------------===// +#ifndef XRAY_EMULATE_TSC_H +#define XRAY_EMULATE_TSC_H + +#include "sanitizer_common/sanitizer_common.h" + +namespace __xray { +static constexpr uint64_t NanosecondsPerSecond = 1000ULL * 1000 * 1000; +} + +#if SANITIZER_FUCHSIA +#include <zircon/syscalls.h> + +namespace __xray { + +inline bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; } + +ALWAYS_INLINE uint64_t readTSC(uint8_t &CPU) XRAY_NEVER_INSTRUMENT { + CPU = 0; + return _zx_ticks_get(); +} + +inline uint64_t getTSCFrequency() XRAY_NEVER_INSTRUMENT { + return _zx_ticks_per_second(); +} + +} // namespace __xray + +#else // SANITIZER_FUCHSIA + +#if defined(__x86_64__) +#include "xray_x86_64.inc" +#elif defined(__powerpc64__) +#include "xray_powerpc64.inc" +#elif defined(__arm__) || defined(__aarch64__) || defined(__mips__) || \ + defined(__hexagon__) || defined(__loongarch_lp64) +// Emulated TSC. +// There is no instruction like RDTSCP in user mode on ARM. ARM's CP15 does +// not have a constant frequency like TSC on x86(_64), it may go faster +// or slower depending on CPU turbo or power saving mode. Furthermore, +// to read from CP15 on ARM a kernel modification or a driver is needed. +// We can not require this from users of compiler-rt. +// So on ARM we use clock_gettime() which gives the result in nanoseconds. +// To get the measurements per second, we scale this by the number of +// nanoseconds per second, pretending that the TSC frequency is 1GHz and +// one TSC tick is 1 nanosecond. +#include "sanitizer_common/sanitizer_common.h" +#include "sanitizer_common/sanitizer_internal_defs.h" +#include "xray_defs.h" +#include <cerrno> +#include <cstdint> +#include <time.h> + +namespace __xray { + +inline bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; } + +ALWAYS_INLINE uint64_t readTSC(uint8_t &CPU) XRAY_NEVER_INSTRUMENT { + timespec TS; + int result = clock_gettime(CLOCK_REALTIME, &TS); + if (result != 0) { + Report("clock_gettime(2) returned %d, errno=%d.", result, int(errno)); + TS.tv_sec = 0; + TS.tv_nsec = 0; + } + CPU = 0; + return TS.tv_sec * NanosecondsPerSecond + TS.tv_nsec; +} + +inline uint64_t getTSCFrequency() XRAY_NEVER_INSTRUMENT { + return NanosecondsPerSecond; +} + +} // namespace __xray + +#else +#error Target architecture is not supported. +#endif // CPU architecture +#endif // SANITIZER_FUCHSIA + +#endif // XRAY_EMULATE_TSC_H |