On Fri, 27 Jan 2023 21:45:37 GMT, Claes Redestad <redes...@openjdk.org> wrote:
>> Scott Gibbons has updated the pull request with a new target base due to a >> merge or a rebase. The incremental webrev excludes the unrelated changes >> brought in by the merge/rebase. The pull request contains 13 additional >> commits since the last revision: >> >> - Merge branch 'openjdk:master' into Base64-AVX2 >> - Merge branch 'openjdk:master' into Base64-AVX2 >> - Merge branch 'openjdk:master' into Base64-AVX2 >> - Merge branch 'Base64-AVX2' of https://github.com/asgibbons/jdk into >> Base64-AVX2 >> - Merge branch 'openjdk:master' into Base64-AVX2 >> - Address review comment >> - Remove whitespace >> - Fix wrong register usage >> - Working version of Base64 decode with AVX2 (4x perf improvement). No URL >> support >> - Merge branch 'Base64-AVX2' of https://github.com/asgibbons/jdk into >> Base64-AVX2 >> - ... and 3 more: https://git.openjdk.org/jdk/compare/52737e0d...3e66f7be > > src/hotspot/cpu/x86/stubGenerator_x86_64.cpp line 2651: > >> 2649: __ jcc(Assembler::notZero, L_tailProc); >> 2650: >> 2651: __ cmpl(length, 44); > > Perform `length` checks first to avoid unnecessary branches on small inputs? > > Ideal might be to move this length check up just before the `_cmpl(length, > 128)` in the AVX-512 block, so that if `AVX=3` short inputs branch directly > to the scalar tail procedure without jumping around. This might also apply to > the encode stub, though that's pre-existing. Done. ------------- PR: https://git.openjdk.org/jdk/pull/12126
