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2021-Feb-12 18:43 UTC
[llvm-dev] Clang performance on ppc64le power8
Dear LLVM Developers, The following are the performance comparisons on some different versions of llvm I used to test my project (running openmp with 2 threads on Power8): GCC/8.2.0 - host compiler: 17 Seconds LLVM/12.0.0 - built with gcc/8.2.0: 27 Seconds LLVM/11.0.0 - Downloaded Pre-built Binaries (PowerPC64LE Red Hat Enterprise Linux <https://github.com/llvm/llvm-project/releases/download/llvmorg-11.0.0/clang+llvm-11.0.0-powerpc64le-linux-rhel-7.4.tar.xz>): 27 Seconds LLVM/8.0.1 - Downloaded Pre-built Binaries ( Red Hat Enterprise Linux 7.4 ppc64le <https://github.com/llvm/llvm-project/releases/download/llvmorg-8.0.1/clang+llvm-8.0.1-powerpc64le-linux-rhel-7.4.tar.xz> ): 17 Seconds It is surprising to find that the older version of llvm/8.0.1 reaches its performance that is close to gcc/8.2.0, while the newer are almost twice as slower than gcc/8.2.0. Any idea about these low performances of newer versions? Best Regards, Shelton -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20210212/1b5de4fd/attachment.html>