[Bug target/77308] surprisingly large stack usage for sha512 on arm

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77308

--- Comment #30 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
(In reply to wilco from comment #29)
>  Combine could help with
> merging 2 loads/stores into a single instruction.

No, combine works strictly on dataflow dependencies.  Two stores cannot be
dataflow related so won't be combined.  Loads would only be dataflow related if
both loads fed into *exactly* one data-processing instruction after the split. 
That's unlikely to happen so I very much dobut it would happen there either.