gmp v4.2: mpx_ or mpuz_ like functions

[ThMO]

Hello all,

while inspecting the gcc-generated assembly code for my general-purpose
factorization program, which I'm using for home-prime searching, the
question arises, if it would be an advantage, if there would be some
unsigned integer functions, e.g. mpx_* or mpuz_*, available, since it
would eliminate all those unnecessary jumps present in the assembly
output.
OTOH would it mean, that those using the unsigned quantities need to
ensure, that for e.g. subtractions the 1st parameter has to be defi=
nitely greather (or equal) than the second parameter.
And it would surely make this library somewhat bigger.
So the question is, is it worth the effort?
What do you people think about it?

THX for listening.

CU Tom.
(Thomas M.Ott)
Germany