Should the CVE2 fence instruction should wait for xif scoreboard?

[ClementChone]

Hi @ClementChone, thanks for this GitHub Issue. I am changing it from a task to a question because I am not certain that a fence should wait for the XIF or not.

Can you provide a specific scenario?

[davideschiavone]

hi @ClementChone - actually, what you say makes sense, as after the fence instruction, you should have a coherent memory scenario, which indeed could be dirty or pending due to X-IF instructions.

The scoreboard busy mechanisms are there exactly for this reason, but indeed the fence instruction doesn't trigger it as it is implemented as a jump to PC+4, as before the X-IF implementation that would have been sufficient, so I will change the pipeline to direct the fence to wait for the scoreboard when the X-Interface parameter is active

Thanks a lot