I came across https://developers.redhat.com/blog/2021/01/05/building-red-hat-enterprise-linux-9-for-the-x86-64-v2-microarchitecture-level/ . Previously, when microbenchmarking Rust code that used count_ones() in an inner loop (can't recall what code this was), I noticed 4x runtime speed when compiling for target_cpu=nehalem and running on a much later CPU.
I'm wondering: Have we done benchmark comparisons with libxul compiled for the newly-defined x86_64 levels? How feasible would it be, considering CI cost, to compile for multiple x86_64 levels and make the Windows installer / updater pick the right one and to use the new glibc-hwcaps mechanism on Linux? For macOS and Android, do we actively track the baseline CPU age that Firefox-compatible OS versions run on and adjust the compiler options accordingly when we drop compatibility for older OS versions? -- Henri Sivonen hsivo...@mozilla.com _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
