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Agner Fog is the usual go-to reference. For this specific case, you can also google any of Linus rants on conditional moves (they used to be very high latency, although today they are not so much of an issue). This one for example: https://yarchive.net/comp/linux/cmov.html

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It is complicated to describe when cmov is slow and when it is fast. As a rule of thumb, if the next loop iteration data operations depend on a cmov in this one, and around, cmov will be slow. If not, it is very, very fast. Use of cmov can make quicksort 2x as fast.

Gcc absolutely won't generate two cmov instructions in a basic block. Clang, for its part, abandons practically all optimization of loops that could conceivably generate a throw.

Nice. Like every other topic, there's more complexity if you keep looking harder.

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