Add support for the RISC-V architecture about pcre2

[zherczeg]

Supporting more cpus never hurt. Unfortunately I don't have much time lately, so this is unlikely happen in the close future.

[PhilipHazel]

Thank you for the comment. I will draw it to the attention of the JIT maintainer.

[zherczeg]

There is an experimental risc-v support in the jit compiler now. It is only tested with qemu, so there might be cache flush issues.

[carenas]

Released with PCRE2 10.41

[ljavorsk]

@PhilipHazel Could you please confirm that the RISC-V is now JIT supported since 10.41? Thank you

[PhilipHazel]

I cannot confirm, but @zherczeg will be able to.

[zherczeg]

I haven't tried it on real hw yet.

[carenas]

I did test it in two rv64g systems (thanks to the gcc compile farm) before it was released; there was one bug that was fixed before the final sync and since autodetection is enabled it is IMHO available for broader use (AFAIK it has been enabled at least in alpine linux already).

It doesn't use compressed instructions or the vector extensions, and assumes hard-float, so it is not "finished" but it should be an improvement over the interpreter in the currently supported configurations and therefore it should be enabled in distributions.

[ljavorsk]

I've built the new 10.42 version on RISC-V Fedora builders and the pcre2-jit test passes, which I assume should test the JIT support.

[zherczeg]

This is great news! Thank you for the feedback.

[aaronfranke]

I haven't been able to test in Godot since we're unable to update PCRE2 for other reasons, but it sounds like everything is working great so I'll close this issue as completed. Thank you everyone!