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> RISC-V (RVA22 profile and up) has a `max` instruction.

You know, it's kind of insane that things like this are nigh impossible to learn from the RISC-V official site. Googling on the site itself doesn't yield anything; you have to go to the "Technical > Specifications" page which has PDFs on the basic ISA from 2019, but not on the newer frozen/ratified extensions, and a link to the "RISC-V Technical Specifications" page on their Attlassian subdomain, where you can find a link to a Google doc "RISC-V profiles" and there you will learn that, indeed Zbb extension is mandatory for RVA22U64 profile (and that, apparently, there is no RVA22U32 profile).

And of course, you have to know that Zbb extension is the one that has max/min/minu/maxu instructions in it; grepping for "min" or "max" won't find you anything. Because why bother listing all the mnemonics of the mandatorily supported function in a document about the sets of instructions with mandatory support? If someone's reading a RISC-V document, they obviously have already read all the other RISC-V docs that predate it, that's the target audience, after all.



There is ongoing work in addressing this.

For one, all of the specs are getting merged into a unified isa-manual, you can get the latest version from github: https://github.com/riscv/riscv-isa-manual/releases

The other project is the riscv-unified-db: https://github.com/riscv-software-src/riscv-unified-db The goal is that this database will hold all specification information in a machine readable format.

That allows you to e.g. generate a manual for RVA22 including the ISA specifications: https://riscv-software-src.github.io/riscv-unified-db/pdfs/R...

Or a website were you can search for instructions, and get all of the relevant information about it: https://riscv-software-src.github.io/riscv-unified-db/exampl...

The above two links are still WIP, so there are still a lot of things missing.




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