udiv_qrnnd_preinv and udiv_rnnd_preinv macros
tg at gmplib.org
Mon Feb 28 15:36:54 CET 2011
nisse at lysator.liu.se (Niels Möller) writes:
> I think it is easy enough to pass a 0 there.
Do you want me to convert uses of udiv_rnd_preinv (r, nh, d, di) to
udiv_rnnd_preinv (r, nh, CNST_LIMB(0), d, di)
and delete udiv_rnd_preinv? And would it work without the somewhat ugly
Please convert, now as it should give the same code.
You can tell better than I if CNST_LIMB is needed. ~0 might not b the
same thing as ~CNST_LIMB(0), since the former is an int, not a limb.
(Not even ~0ul is safe, since mp_limb_t might b a long long.)
So, remove CNST_LIMB if is uses safely. Consider using a cast inside
the function if needed.
With a compiler supporting __builtin_constant_p, it ought to generate
the same code, but without __builtin_constant_p, using udiv_rnnd_preinv
with nl == 0 is going to be slightly less efficient.
One cannot please them all. :-)
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