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<div> broadcasts that get hoisted out of the loop, etc.</div>
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Can you elaborate? Do you mean that we're hoisting broadcasts
outside of the trip-count check (i.e. speculatively executing them)
and these are actually expensive operations? Is this is a cost-model
problem being exposed by SimplifyCFG (which is hoisting these things
outside of the trip-count check)?</div></blockquote><div><br></div><div>I'm pretty sure I've seen this happen. We're definitely hoisting them out of the loop (and relying on CGP and/or Loop Sinking to sink them back when profitable), but I also remember seeing the broadcasts executed in cases where the the iteration count was 0.</div><div><br></div><div>I'll see if I can come up with an example.</div></div></div></div>