New register usage pattern allows to achieve sligtly better
performance. Not as much as I hoped for. Performance is believed
to be limited by irreconcilable write-back conflicts, rather than
lack of computational resources or data dependencies.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This gives much more freedom to rearrange instructions. This is
unoptimized version, provided for reference. Basically you need
to compare it to initial 29724d0e15
to figure out the key difference.
Reviewed-by: Rich Salz <rsalz@openssl.org>