Mercurial > dropbear

annotate tomsfastmath/src/addsub/s_fp_add.c @ 646:f10335e5e42f dropbear-tfm

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
- More asm constraint fixes. Now seems to build OK on 32-bit OS X.
author Matt Johnston <matt@ucc.asn.au>
date Wed, 30 Nov 2011 23:03:47 +0800
parents a362b62d38b2
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
643
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* TomsFastMath, a fast ISO C bignum library.
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * This project is meant to fill in where LibTomMath
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * falls short. That is speed ;-)
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * This project is public domain and free for all purposes.
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 *
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 * Tom St Denis, [email protected]
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 */
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 #include <tfm.h>
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 /* unsigned addition */
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 void s_fp_add(fp_int *a, fp_int *b, fp_int *c)
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 {
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 int x, y, oldused;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 register fp_word t;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 y = MAX(a->used, b->used);
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 oldused = c->used;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 c->used = y;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 t = 0;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 for (x = 0; x < y; x++) {
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 t += ((fp_word)a->dp[x]) + ((fp_word)b->dp[x]);
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 c->dp[x] = (fp_digit)t;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 t >>= DIGIT_BIT;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 }
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 if (t != 0 && x < FP_SIZE) {
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 c->dp[c->used++] = (fp_digit)t;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 ++x;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 }
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 c->used = x;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 for (; x < oldused; x++) {
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 c->dp[x] = 0;
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 }
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 fp_clamp(c);
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 }
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 /* $Source$ */
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 /* $Revision$ */
a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 /* $Date$ */