PeterRugg
PeterRugg
@billmcspadden-riscv 1. I didn't think I should disrupt the sail model that much: presumably somebody did this intentionally because they had to jump through hoops to do it. I think...
A few thoughts on testing, as I'm not super clear on what tests would look like: 1. It seems the HINT cases should be included in the RVC tests regardless...
@jrtc27 Fine by me. I'm happy to do a PR to simplify things back again.
I guess the prose spec really doesn't allow that interpretation: presumably they want to make absolutely sure that non-extended code can't use the HINTs and expect them to be nops.
Hmm, interesting. IIRC, this change should only affect tracing rather than whether instructions are legal or not.
Would work fine for me!
@PeterSewell In TestRIG we use RVFI, as documented here https://github.com/CTSRD-CHERI/TestRIG/blob/master/RVFI-DII.md#rvfi-dii-execution-packet-88-bytes. I guess a pro is that it's supported by the model already, though may need a little work to ensure...
> you could add an external hint function This sounds quite tidy. Having `hint` defined as a Sail empty function and calling it in the semantic function of the compressed...
@Timmmm But then the integer compressed instructions should clear the metadata because they're writing back integers, even if they would be a nop on the address part.
@bacam But this is definitely CHERI's problem to solve. I agree with @Timmmm: if they're not naturally nops in CHERI then we'll probably keep their metadata-clearing behaviour, and add a...