Recent set of changes (PR #67725) in loop interleaving algorithm caused removal of the loop trip count threshold for allowing interleaving. Therefore configuration option interleave-small-loop-scalar-reduction is no longer needed.
Interleave for small loops that have reductions inside,
which breaks dependencies and expose.
This gives very significant performance improvements for some benchmarks.
Because small loops could be in very hot functions in real applications.
Differential Revision: https://reviews.llvm.org/D81416
