[PATCH 00/10] RISC-V: Refactor instructions

Andrew Jones ajones at ventanamicro.com
Thu Sep 7 01:51:49 PDT 2023


On Wed, Sep 06, 2023 at 11:51:05AM -0700, Charlie Jenkins wrote:
> On Fri, Aug 18, 2023 at 09:30:32AM +0200, Andrew Jones wrote:
> > On Thu, Aug 17, 2023 at 10:52:22AM -0700, Palmer Dabbelt wrote:
> > > On Thu, 17 Aug 2023 09:43:16 PDT (-0700), Charlie Jenkins wrote:
> > ...
> > > > It seems to me that it will be significantly more challenging to use
> > > > riscv-opcodes than it would for people to just hand create the macros
> > > > that they need.
> > > 
> > > Ya, riscv-opcodes is pretty custy.  We stopped using it elsewhere ages ago.
> > 
> > Ah, pity I didn't know the history of it or I wouldn't have suggested it,
> > wasting Charlie's time (sorry, Charlie!). So everywhere that needs
> > encodings are manually scraping them from the PDFs? Or maybe we can write
> > our own parser which converts adoc/wavedrom files[1] to Linux C?
> > 
> > [1] https://github.com/riscv/riscv-isa-manual/tree/main/src/images/wavedrom
> 
> The problem with the wavedrom files is that there are no standard for
> how each instruction is identified. The title of of the adoc gives some
> insight and there is generally a funct3 or specific opcode that is
> associated with the instruction but it would be kind of messy to write a
> script to parse that. I think manually constructing the instructions is
> fine. When somebody wants to add a new instruction they probably will
> not need to add very many at a time, so it should be only a couple of
> lines that they will be able to test.
>

OK, we'll just have to prop our eyelids open with toothpicks to get
through the review of the initial mass conversion.

Thanks,
drew



More information about the linux-riscv mailing list