So the difference is block everything until the dependency is available and then continue immediately, vs give up on time slots already reserved for downstream dependencies while continuing with those parts in the current schedule that are not blocked and copy the blocked parts at the end of the queue? Sounds like a trade-off that can go one way or the other? But yeah, I was using the term "stalling" in a browser sense, as the superset of both. No idea how incorrect that is.

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IshKebab 3 days ago | parent [-]

Yeah I think even traditional OoO designs use replay for missed loads rather than stalling. The performance would be too bad if it actually stalled for every load.

I think stalling is used for rarer more awkward things like changing privilege modes or writing certain CSRs (e.g. satp) where you don't want to have to maintain speculative state.

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monocasa 3 days ago | parent [-]

Traditional OoO designs don't stall for loads per se, but will stall for a full ROB that has a chain of dependencies waiting on the results of the load.

	▲	IshKebab 3 days ago \| parent [-]
		Good point, but I guess that's the sort of delay that you can't avoid. If there's literally no work to do until a load is available you have to wait. This design can't avoid that either.