RFR: 8312425: [vectorapi] AArch64: Optimize vector math operations with SLEEF [v6]

[Xiaohong Gong]

On Fri, 1 Dec 2023 16:26:02 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

>> Xiaohong Gong 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 ten additional commits since the last revision:
>> 
>>  - Separate neon and sve functions into two source files
>>  - Merge branch 'jdk:master' into JDK-8312425
>>  - Rename vmath to sleef in configure
>>  - Address review comments in build system
>>  - Add a bundled native lib in jdk as a bridge to libsleef
>>  - Merge 'jdk:master' into JDK-8312425
>>  - Disable sleef by default
>>  - Merge 'jdk:master' into JDK-8312425
>>  - 8312425: [vectorapi] AArch64: Optimize vector math operations with SLEEF
>
> doc/building.md line 639:
> 
>> 637: 
>> 638: libsleef, the [SIMD Library for Evaluating Elementary Functions](
>> 639: https://sleef.org/) is required when building libvmath.so on Linux/aarch64
> 
> This is incorrect. The library is not required, but if it is present, we will build libvmath with it.
> 
> Edit: Or rather, this is misleading. Technically it is correct, since you state that it is required when building libvmath.so, but it is easy to mistake for being required for building the JDK. The reader presumably does not know what libvmath.so is or how it is used.
> 
> Please rephrase this to so that it is clear that this is optional, but will provide performance benefits to the resulting JDK if present. You do not need to mention libvmath.so here, for no other dependency do we declare what parts of the JDK that require it -- it is not essential for this document.
> 
> Also see if you can make this paragraph and the one at the end be a bit more tighter, not the last paragraph seems to be both repeat and contradict this one.

Hi @magicus , the doc is updated. Thanks for your comment on this!

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PR Review Comment: https://git.openjdk.org/jdk/pull/16234#discussion_r1416964362