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[all]: Add support for SVE fault tolerant instructions #876
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SVE adds instructions which can suppresses memory fault, specifically: - Load first-fault - Load non-fault - Auxiliary instructions to inspect First Fault Register (FFR)
@maranget , @relokin I've run into inserting case where SVE load instructions can suppress fault. I noticed that non-vector instructions use
So, I'm seeking your advice on how to progress with that? Thanks! |
Thanks for this @murzinv, perhaps before adding support for these new instructions, or in parallel with this change, we need to add vmsa support for the existing vector instructions. Looking at the pseudocode, it looks like we have one translation/tag check per element memory read/write. I am looking specifically at |
Cannot disagree with that 😄
Correct.
I assume that in such case every store of the element would end-up with either |
I think it's B.Next or B.Fault that we want. The instruction should raise a fault, but, also, I suspect that it's architecturally allowed to see from 0 to all non-faulting, active element write happening before entering the fault handler. That might mean multiple architecturally allowed executions just because one element read/write generates a fault. |
SVE adds instructions which can suppresses memory fault, specifically: