?swap: Swap values of two arrays. As fast as you can, dear

General Usage
1

LAPACK has a function called ?swap to swap the values stored in two arrays

      subroutine  dswap (n,dx,incx,dy,incy)
#
#     interchanges two vectors.
#     uses unrolled loops for increments equal one.
#     jack dongarra, linpack, 3/11/78.
#     modified 12/3/93, array(1) declarations changed to array(*)

This does not seem to be implemented in LinearAlgebra. (Maybe I have just looked in the wrong places.)

But the question is, how would this be done with the highest performance in Julia? I really do need to swap the values, not just the identifiers, by the way, because this will typically be done on slices.

2

LoopVectoriztion should give optimal assembly for the trivial implementation.

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