On Tue, 7 Feb 2023 00:12:21 GMT, Scott Gibbons <d...@openjdk.org> wrote:
>> Added code for Base64 acceleration (encode and decode) which will accelerate >> ~4x for AVX2 platforms. >> >> Encode performance: >> **Old:** >> >> Benchmark (maxNumBytes) Mode Cnt Score Error >> Units >> Base64Encode.testBase64Encode 1024 thrpt 3 4309.439 ± 2.632 >> ops/ms >> >> >> **New:** >> >> Benchmark (maxNumBytes) Mode Cnt Score >> Error Units >> Base64Encode.testBase64Encode 1024 thrpt 3 24211.397 ± >> 102.026 ops/ms >> >> >> Decode performance: >> **Old:** >> >> Benchmark (errorIndex) (lineSize) (maxNumBytes) >> Mode Cnt Score Error Units >> Base64Decode.testBase64Decode 144 4 1024 >> thrpt 3 3961.768 ± 93.409 ops/ms >> >> **New:** >> Benchmark (errorIndex) (lineSize) (maxNumBytes) >> Mode Cnt Score Error Units >> Base64Decode.testBase64Decode 144 4 1024 >> thrpt 3 14738.051 ± 24.383 ops/ms > > Scott Gibbons has updated the pull request incrementally with one additional > commit since the last revision: > > Add algorithm comments src/hotspot/cpu/x86/stubGenerator_x86_64.cpp line 2227: > 2225: > 2226: // lut_roll URL > 2227: __ emit_data64(0xb9b9bfbf04111000, relocInfo::none); The lut_roll URL doesn't seem to be correct: 0x5F (URL base64 ASCII for "/") would need an offset of -20H i.e. 0xEC. However the others with upper nibble as 5 need an offset of -65H i.e. 0xBF. It looks to me that the adjustment for 5F should be -4 instead of -1 at line 2722. ------------- PR: https://git.openjdk.org/jdk/pull/12126
