What is "coherent control flow"? Is it the masking out of divergent control flow paths, as discussed on slide 88?
@sboucher. Coherent control flow exists when multiple logical instruction streams follow the same control flow sequence, and thus can be executed together in a SIMD manner. (The absence of instruction stream coherence is referred to as divergent control flow.)
Slide 88 is illustrating an example of incoherent control flow. If all the iterations of the loop took the same branch, we'd say control flow of each of those loop iterations is coherent.