386 optimized bitblit code

Kevin Ryde user42 at zip.com.au
Tue Feb 10 01:16:04 CET 2004

Brian Hurt <bhurt at spnz.org> writes:
> Attached is a first cut at 386-optimized code.

Unless I've missed something, what you're doing looks like either
mpn_lshift or mpn_rshift, according to the overlap direction.  See
that code for what it takes to go fast on x86s.  (In particular mmx is
usually what you want for the mmx chips, shrdl is sub-optimal on say
athlon, and very slow on pentium4.)

More information about the gmp-devel mailing list