On Mon, 28 Jun 2010 18:18:46 -0400, bearophile <bearophileh...@lycos.com>
wrote:
Steven Schveighoffer:
What's wrong with d2's bigint that Don has written?
MPIR is "not invented here" :-) Moving part of the development of a very
tricky part of code full of long asm routines (see their amount of code
finely tuned for different CPUs) to someone else that has more resources
and dedication is sometimes positive. It frees Don to do something else
for D, allows to use potentially less buggy code (because more people
use the same lib), and MPIR contains several good numerical algos and
numeric types that are missing in Don's bigint.
By the way, even if MPIR gets a Boost licence some work can be useful to
adapt it to D, because in D I'd like the multi-precision integrals to be
very efficient even when they are used with numbers about 32 bits long
or less, so in some programs they can be a replacement of normal
integers. This can be done using an union with a tag and switching to
normal integer operations when numbers are small (in this case zero
memory is allocated on the heap to keep such numbers). I don't know if
MPIR is already performing this optimization, I think it is not (I have
asked this small-number optimization in Don's bigints too in past, and I
think he likes this idea).
OK, I thought you meant we should discard the current bigint in favor of
some other implementation. I wasn't aware that D2's bigint still had
missing features (I haven't used it).
-Steve
