[LegionMammal978]

Not if, like most people, you still aren't using a CPU with AVX-512 support. And I don't recall ever seeing it in compiler output in any case. It's not like boolean operations on three variables occur very frequently in most programs, especially (EDIT: this last part apparently isn't the case) not operations that can't be decomposed into a pair of two-variable operations with no worse performance.

[dzaima]

As far as everything on uops.info goes, ternlog has the same throughput and latency as the two-operand logic instructions everywhere (with the mild exception of Zen 4 where it goes from 0.50 to 0.56 cycles/instr; which also shows as having 2-cycle latency to one operand but I think that might be measurement error), so it's always bad to decompose ternlog into two two-operand logic ops.