[PATCH] aarch64: Improve codegen in users of ADVSIMD expm1 helper

[Wilco Dijkstra]

Hi Pierre,

> Add inline helper for expm1 and rearrange operations so MOV
> is not necessary in reduction or around the special-case handler.
> Reduce memory access by using more indexed MLAs in polynomial.
> Speedup on Neoverse V1 for expm1 (19%), sinh (8.5%), and tanh (7.5%).
> ---
> OK for master? If so please commit for as I don't have commit rights.

OK. Pushed.

Cheers,
Wilco