MIPS: Add support for MIPS MSA SIMD.

[alexfru]

I may provide instructions on how to set up the compilers, build the tests for MIPS and run them. Let me know if/when you want this.

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[alexfru]

I'm an AOSP contributor (look up Alexey Frunze in e.g. art). Do I still need to do something about the CLA?

[bjacob]

Hi Alex,

Thanks for the contribution.

Can you share a bit about your motivation for MIPS support: this is a substantial expansion of gemmlowp's set of hardware targets, and I need to understand some rationale for it. Do you have a specific use case for MIPS support or is this done 'for the beauty of it' ? (I understand this might be hard to discuss; just a yes/no answer is fine).

Regarding the CLA, you need to sign it, but it can be either individual (if you are legally the author of this work) or corporate (if acting on behalf of your employer i.e. your employer is the legal 'author' and you're just a 'contributor').

[alexfru]

I'm acting on behalf of the employer (MIPS), just as with AOSP. The answer to the other question is yes (for a more elaborate answer we could probably go private). Including @glraghukishore, my direct manager.

[bjacob]

OK, thanks for the reply.

If your employer is the copyright holder of the open-source code that you contribute, then:

1. your employer needs to sign the Google CLA, if not already done;
2. the PR needs to be updated to mention your employer in AUTHORS and yourself in CONTRIBUTORS.

Unless another Googler here feels otherwise, I'm going to default to saying that MIPS caring enough about this to contribute this code is a solid enough reason to take it, so that issue is cleared too. Just please note that I and other gemmlowp maintainers don't have much experience with MIPS hardware and don't have local hardware to test this code. So I have to say there are no guarantees of not regressing this code, though in practice, gemmlowp being widely used, it is possible that some test targets will exercise it on MIPS somewhere.

[googlebot]

CLAs look good, thanks!

[bjacob]

Thanks, the patch looks perfect, well well integrated! Merging.