[libre-riscv-dev] SV Prefix questions
Luke Kenneth Casson Leighton
lkcl at lkcl.net
Wed Jun 26 11:25:11 BST 2019
On Wed, Jun 26, 2019 at 10:39 AM Jacob Lifshay <programmerjake at gmail.com> wrote:
> bit 31 is for differentiating rs2/imm, which is not needed for SV,
> therefore I picked the vsetvli encoding hoping to allow
> implementations that implement both rvv and SV to share more gates in
> the decoder.
... and matching disasm (etc.)
> rs1 handling matches how it's defined in rvv.
what are they dooooiiing with the immeeeediaaaate?? mmooooo? :)
ok so actually bit 31=1 says "brownfield encoding" - some funct7
things can still fit in that (just with 25:30 only).
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