Mercurial > dropbear
view tomsfastmath/src/bit/fp_count_bits.c @ 645:8622ee48fab5 dropbear-tfm
- Work around broken asm constraint behaviour on 32bit x86 OS X
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Wed, 30 Nov 2011 22:27:26 +0800 |
parents | a362b62d38b2 |
children |
line wrap: on
line source
/* TomsFastMath, a fast ISO C bignum library. * * This project is meant to fill in where LibTomMath * falls short. That is speed ;-) * * This project is public domain and free for all purposes. * * Tom St Denis, [email protected] */ #include <tfm.h> int fp_count_bits (fp_int * a) { int r; fp_digit q; /* shortcut */ if (a->used == 0) { return 0; } /* get number of digits and add that */ r = (a->used - 1) * DIGIT_BIT; /* take the last digit and count the bits in it */ q = a->dp[a->used - 1]; while (q > ((fp_digit) 0)) { ++r; q >>= ((fp_digit) 1); } return r; } /* $Source$ */ /* $Revision$ */ /* $Date$ */