RFR: 8333867: SHA3 performance can be improved

[Ferenc Rakoczi]

On Mon, 10 Jun 2024 15:01:55 GMT, Ferenc Rakoczi <duke at openjdk.org> wrote:

> This PR removes some unnecessary conversions between byte arrays and long arrays during SHA3 digest computations.

Some microbenchmark data (the percentages are improvements in ops/sec):
Benchmark                                                                                                                                                                       Linux aarch64  Linux x64  MacOSX aarch64  MacOSX x64
openjdk.bench.java.security.MessageDigests.digest-digesterName:SHA3_256-length:16384-provider:DEFAULT         27.67%     20.60%          -0.00%      24.75%
openjdk.bench.java.security.MessageDigests.digest-digesterName:SHA3_256-length:64-provider:DEFAULT            11.95%      6.27%          -3.97%      12.72%
openjdk.bench.java.security.MessageDigests.digest-digesterName:SHA3_512-length:16384-provider:DEFAULT         18.00%     14.99%           0.01%      15.35%
openjdk.bench.java.security.MessageDigests.digest-digesterName:SHA3_512-length:64-provider:DEFAULT            11.91%      5.87%          -3.39%      10.04%

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PR Comment: https://git.openjdk.org/jdk/pull/19632#issuecomment-2160317942