forked from OSchip/llvm-project
5856f30b5a
This patch adds a configuration option to simply use the default pass pipeline in favor of the LTO-specific one. We observed some severe performance penalties when uding device-side LTO for OpenMP offloading applications caused by the LTO-pass pipeline. This is primarily because OpenMP uses an LLVM bitcode library to implement a GPU runtime library. In a standard compilation we link this bitcode library into each source file and optimize it with the default pipeline. When performing LTO we link it late with all the files, but the bitcode library never has the regular optimization pipeline applied to it so we miss a few optimizations just using the LTO pipeline to optimize it. I'm not committed to this solution, but it's the easiest method to solve this performance regression when using LTO without changing the optimizatin pipeline for other users. Reviewed By: tianshilei1992 Differential Revision: https://reviews.llvm.org/D122133 |
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| .. | ||
| CMakeLists.txt | ||
| ClangLinkerWrapper.cpp | ||
| OffloadWrapper.cpp | ||
| OffloadWrapper.h | ||