| // Copyright 2019 The Dawn 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 |
| // |
| // http://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. |
| |
| #include <CoreServices/CoreServices.h> |
| #include <mach/mach.h> |
| #include <mach/mach_time.h> |
| |
| #include "dawn/utils/Timer.h" |
| |
| namespace utils { |
| |
| class OSXTimer : public Timer { |
| public: |
| OSXTimer() : Timer(), mRunning(false), mSecondCoeff(0) {} |
| |
| ~OSXTimer() override = default; |
| |
| void Start() override { |
| mStartTime = mach_absolute_time(); |
| // Cache secondCoeff |
| GetSecondCoeff(); |
| mRunning = true; |
| } |
| |
| void Stop() override { |
| mStopTime = mach_absolute_time(); |
| mRunning = false; |
| } |
| |
| double GetElapsedTime() const override { |
| if (mRunning) { |
| return mSecondCoeff * (mach_absolute_time() - mStartTime); |
| } else { |
| return mSecondCoeff * (mStopTime - mStartTime); |
| } |
| } |
| |
| double GetAbsoluteTime() override { return GetSecondCoeff() * mach_absolute_time(); } |
| |
| private: |
| double GetSecondCoeff() { |
| // If this is the first time we've run, get the timebase. |
| if (mSecondCoeff == 0.0) { |
| mach_timebase_info_data_t timebaseInfo; |
| mach_timebase_info(&timebaseInfo); |
| |
| mSecondCoeff = timebaseInfo.numer * (1.0 / 1000000000) / timebaseInfo.denom; |
| } |
| |
| return mSecondCoeff; |
| } |
| |
| bool mRunning; |
| uint64_t mStartTime; |
| uint64_t mStopTime; |
| double mSecondCoeff; |
| }; |
| |
| Timer* CreateTimer() { |
| return new OSXTimer(); |
| } |
| |
| } // namespace utils |