| /* Copyright 2016 The TensorFlow Authors. All Rights Reserved. |
| |
| 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. |
| ==============================================================================*/ |
| |
| #ifndef TENSORFLOW_COMPILER_XLA_SERVICE_GPU_FUSION_MERGER_H_ |
| #define TENSORFLOW_COMPILER_XLA_SERVICE_GPU_FUSION_MERGER_H_ |
| |
| #include "tensorflow/compiler/xla/service/hlo_module.h" |
| #include "tensorflow/compiler/xla/service/hlo_pass_interface.h" |
| |
| namespace xla { |
| namespace gpu { |
| |
| // An HLO pass that attempts to merge fusion instructions to reduce kernel |
| // launch overhead and improve data locality. |
| // |
| // Fusion instructions are merged into their users if two conditions are met: |
| // |
| // 1) The flops_to_bytes ratio of the fusion instruction is below the threshold |
| // value of 1.0. |
| // 2) The result of merging the fusion instruction into its users would not |
| // increase bytes transferred. |
| // |
| class FusionMerger : public HloModulePass { |
| public: |
| absl::string_view name() const override { return "fusion merger"; } |
| |
| StatusOr<bool> Run(HloModule* module) override; |
| |
| static double GetThresholdFlopsToBytesRatio() { return 1.0; } |
| }; |
| |
| } // namespace gpu |
| } // namespace xla |
| |
| #endif // TENSORFLOW_COMPILER_XLA_SERVICE_GPU_FUSION_MERGER_H_ |