Mercurial > dropbear
view tomsfastmath/src/addsub/s_fp_add.c @ 643:a362b62d38b2 dropbear-tfm
Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
with Makefile.in renamed
author | Matt Johnston <matt@ucc.asn.au> |
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date | Wed, 23 Nov 2011 18:10:20 +0700 |
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/* 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> /* unsigned addition */ void s_fp_add(fp_int *a, fp_int *b, fp_int *c) { int x, y, oldused; register fp_word t; y = MAX(a->used, b->used); oldused = c->used; c->used = y; t = 0; for (x = 0; x < y; x++) { t += ((fp_word)a->dp[x]) + ((fp_word)b->dp[x]); c->dp[x] = (fp_digit)t; t >>= DIGIT_BIT; } if (t != 0 && x < FP_SIZE) { c->dp[c->used++] = (fp_digit)t; ++x; } c->used = x; for (; x < oldused; x++) { c->dp[x] = 0; } fp_clamp(c); } /* $Source$ */ /* $Revision$ */ /* $Date$ */