[m-rev.] for review 2/4: Add RISC-V hardware register support (reg grades)

[Julien Fischer]

On Fri, 17 Mar 2023, Paul Bone wrote:

> This change enables Mercury to use the the first four caller-save
> registers for its first four registers.  RISC-V has 12 caller-save
> registers so we could try with more.
>
> runtime/machdeps/riscv_regs.h:
>    As above.
>
> runtime/mercury_regs.h:
> runtime/Mmakefile:
>    Include machdeps/riscv_regs.h

That's fine; I assume you have fixed the s/caller/callee/ issue as per
your other mail.

Julien.