I have to find an index / position of an 8-bit value element N in an array ARR via SIMD. It has to be a fast fashion.
At the moment the algorithm is that I would load 8-bit values of ARR into a SIMD register and a character code of N into another SIMD register.
Then I would use the negation and check which byte succeeds with popcnt. The operations can be used saturated if necessary.
This is x86-64.
Is there a faster way?