RFR: 8310837: Use ByteArrayLittleEndian in java.util.zip

[Jaikiran Pai]

On Fri, 23 Jun 2023 20:00:12 GMT, Glavo <duke at openjdk.org> wrote:

> Using `ByteArrayLittleEndian` is simpler and faster.
> 
> `make test TEST="micro:java.util.zip.ZipFileOpen"`:
> 
> 
>   Benchmark                     (size)  Mode  Cnt      Score      Error  Units
> - ZipFileOpen.openCloseZipFile     512  avgt   15  39052.832 ±  107.496  ns/op
> + ZipFileOpen.openCloseZipFile     512  avgt   15  36275.539 ±  663.193  ns/op
> - ZipFileOpen.openCloseZipFile    1024  avgt   15  77106.494 ± 4159.300  ns/op
> + ZipFileOpen.openCloseZipFile    1024  avgt   15  71955.013 ± 2296.050  ns/op

Hello Glavo,

> @AlanBateman @jaikiran Sorry, I thought about its possible impact on startup time, but I don't know which tests can be used to test JVM startup time. Can you tell me some relevant tests?
> 
> In fact, I now have a branch(#14636) that rewrites `ByteArray` and `ByteArrayLittleEndian` to avoid using `VarHandle` because I hope to be able to use them more inside the JDK later.
> 

I think this PR should then wait for a bit to see what comes out of https://github.com/openjdk/jdk/pull/14636. That will then help us understand what kind of additional testing might have to be considered for this current PR.

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PR Comment: https://git.openjdk.org/jdk/pull/14632#issuecomment-1606715060