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-rw-r--r--third_party/abseil_cpp/absl/base/internal/cycleclock.cc107
1 files changed, 0 insertions, 107 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/cycleclock.cc b/third_party/abseil_cpp/absl/base/internal/cycleclock.cc
deleted file mode 100644
index 0e65005b8914..000000000000
--- a/third_party/abseil_cpp/absl/base/internal/cycleclock.cc
+++ /dev/null
@@ -1,107 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// The implementation of CycleClock::Frequency.
-//
-// NOTE: only i386 and x86_64 have been well tested.
-// PPC, sparc, alpha, and ia64 are based on
-//    http://peter.kuscsik.com/wordpress/?p=14
-// with modifications by m3b.  See also
-//    https://setisvn.ssl.berkeley.edu/svn/lib/fftw-3.0.1/kernel/cycle.h
-
-#include "absl/base/internal/cycleclock.h"
-
-#include <atomic>
-#include <chrono>  // NOLINT(build/c++11)
-
-#include "absl/base/internal/unscaledcycleclock.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace base_internal {
-
-#if ABSL_USE_UNSCALED_CYCLECLOCK
-
-namespace {
-
-#ifdef NDEBUG
-#ifdef ABSL_INTERNAL_UNSCALED_CYCLECLOCK_FREQUENCY_IS_CPU_FREQUENCY
-// Not debug mode and the UnscaledCycleClock frequency is the CPU
-// frequency.  Scale the CycleClock to prevent overflow if someone
-// tries to represent the time as cycles since the Unix epoch.
-static constexpr int32_t kShift = 1;
-#else
-// Not debug mode and the UnscaledCycleClock isn't operating at the
-// raw CPU frequency. There is no need to do any scaling, so don't
-// needlessly sacrifice precision.
-static constexpr int32_t kShift = 0;
-#endif
-#else
-// In debug mode use a different shift to discourage depending on a
-// particular shift value.
-static constexpr int32_t kShift = 2;
-#endif
-
-static constexpr double kFrequencyScale = 1.0 / (1 << kShift);
-static std::atomic<CycleClockSourceFunc> cycle_clock_source;
-
-CycleClockSourceFunc LoadCycleClockSource() {
-  // Optimize for the common case (no callback) by first doing a relaxed load;
-  // this is significantly faster on non-x86 platforms.
-  if (cycle_clock_source.load(std::memory_order_relaxed) == nullptr) {
-    return nullptr;
-  }
-  // This corresponds to the store(std::memory_order_release) in
-  // CycleClockSource::Register, and makes sure that any updates made prior to
-  // registering the callback are visible to this thread before the callback is
-  // invoked.
-  return cycle_clock_source.load(std::memory_order_acquire);
-}
-
-}  // namespace
-
-int64_t CycleClock::Now() {
-  auto fn = LoadCycleClockSource();
-  if (fn == nullptr) {
-    return base_internal::UnscaledCycleClock::Now() >> kShift;
-  }
-  return fn() >> kShift;
-}
-
-double CycleClock::Frequency() {
-  return kFrequencyScale * base_internal::UnscaledCycleClock::Frequency();
-}
-
-void CycleClockSource::Register(CycleClockSourceFunc source) {
-  // Corresponds to the load(std::memory_order_acquire) in LoadCycleClockSource.
-  cycle_clock_source.store(source, std::memory_order_release);
-}
-
-#else
-
-int64_t CycleClock::Now() {
-  return std::chrono::duration_cast<std::chrono::nanoseconds>(
-             std::chrono::steady_clock::now().time_since_epoch())
-      .count();
-}
-
-double CycleClock::Frequency() {
-  return 1e9;
-}
-
-#endif
-
-}  // namespace base_internal
-ABSL_NAMESPACE_END
-}  // namespace absl