On Thu, 23 Nov 2023 15:43:34 GMT, Andrew Haley <a...@openjdk.org> wrote:
>> Xiaohong Gong has updated the pull request incrementally with one additional >> commit since the last revision: >> >> Address review comments in build system > > make/autoconf/lib-vmath.m4 line 94: > >> 92: # Check the ARM SVE feature >> 93: SVE_CFLAGS="-march=armv8-a+sve" >> 94: > > What's this about? We're building a standard binary, and all SVE detection is > to be deferred to runtime. We have to use this c-compiler option to build out the SVE ABIs (e.g. `svfloat32_t sinfx_u10sve(svfloat32_t input)`) in `libvmath.so`. Without this option, at build time, all the sve related featues like `arm_sve.h / __ARM_FEATURE_SVE` are missing, together with the sve symbols in `libvmath.so` we needed at runtime. That means at runtime, hotspot cannot find out the sve symbols and the vector operations will fall back to the default java implementation. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/16234#discussion_r1405529521
