[libcxx-commits] [libcxx] [libc++] Tiny optimizations for is_permutation (PR #129565)

[Imad Aldij via libcxx-commits]

imdj wrote:

Based on initial results [from benchmarks](https://github.com/llvm/llvm-project/pull/130387) this implementation doesn't (yet) offer better performance. I will try to profile it and tweak few things.

https://github.com/llvm/llvm-project/pull/129565