RFR: 8329816: Add SLEEF version 3.6.1

[Erik Joelsson]

On Thu, 29 Aug 2024 23:07:16 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

> [JDK-8312425](https://bugs.openjdk.org/browse/JDK-8312425) is looking to optimize vector math operations by leveraging the SLEEF library. For legal reasons the actual contribution of the SLEEF files needs to be handled separately.
> 
> This is a new attempt at solving [JDK-8329816](https://bugs.openjdk.org/browse/JDK-8329816); the original attempt is here: https://github.com/openjdk/jdk/pull/19185. This PR is based on the discussions on how to move forward that was held in that original PR.

I replicated the generation using the instructions in the readme. It worked but the generated files end up with large whitespace differences, probably because you generated them before cleaning the whitespace in the original sources. If that is the case, could you update the generated files from the exact upstream sources that were committed?

make/UpdateSleefSource.gmk line 38:

> 36: ################################################################################
> 37: # This file is responsible for updating the generated sleef source code files
> 38: # that are checked in to the JDK repo, and that is actually used when building.

Suggestion:

# that are checked in to the JDK repo, and that are actually used when building.

src/jdk.incubator.vector/linux/native/libsleef/README.md line 29:

> 27: `https://github.com/shibatch/sleef.git`, and copy all files, except the `docs`
> 28: and `.github` directories, into
> 29: `src/jdk.incubator.vector/linux/native/libsleef/upstream`.

I think you need to add something about the need for whitespace cleanup here.

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PR Review: https://git.openjdk.org/jdk/pull/20781#pullrequestreview-2272399884
PR Review Comment: https://git.openjdk.org/jdk/pull/20781#discussion_r1738702398
PR Review Comment: https://git.openjdk.org/jdk/pull/20781#discussion_r1738715361