1 b3f61791 2004-03-21 devnull #include "os.h"
 2 b3f61791 2004-03-21 devnull #include <mp.h>
 3 b3f61791 2004-03-21 devnull #include "dat.h"
 4 b3f61791 2004-03-21 devnull 
 5 cbeb0b26 2006-04-01 devnull /* sum = abs(b1) + abs(b2), i.e., add the magnitudes */
 6 b3f61791 2004-03-21 devnull void
 7 b3f61791 2004-03-21 devnull mpmagadd(mpint *b1, mpint *b2, mpint *sum)
 8 b3f61791 2004-03-21 devnull {
 9 b3f61791 2004-03-21 devnull 	int m, n;
10 b3f61791 2004-03-21 devnull 	mpint *t;
11 b3f61791 2004-03-21 devnull 
12 cbeb0b26 2006-04-01 devnull 	/* get the sizes right */
13 b3f61791 2004-03-21 devnull 	if(b2->top > b1->top){
14 b3f61791 2004-03-21 devnull 		t = b1;
15 b3f61791 2004-03-21 devnull 		b1 = b2;
16 b3f61791 2004-03-21 devnull 		b2 = t;
17 b3f61791 2004-03-21 devnull 	}
18 b3f61791 2004-03-21 devnull 	n = b1->top;
19 b3f61791 2004-03-21 devnull 	m = b2->top;
20 b3f61791 2004-03-21 devnull 	if(n == 0){
21 b3f61791 2004-03-21 devnull 		mpassign(mpzero, sum);
22 b3f61791 2004-03-21 devnull 		return;
23 b3f61791 2004-03-21 devnull 	}
24 b3f61791 2004-03-21 devnull 	if(m == 0){
25 b3f61791 2004-03-21 devnull 		mpassign(b1, sum);
26 b3f61791 2004-03-21 devnull 		return;
27 b3f61791 2004-03-21 devnull 	}
28 b3f61791 2004-03-21 devnull 	mpbits(sum, (n+1)*Dbits);
29 b3f61791 2004-03-21 devnull 	sum->top = n+1;
30 b3f61791 2004-03-21 devnull 
31 b3f61791 2004-03-21 devnull 	mpvecadd(b1->p, n, b2->p, m, sum->p);
32 b3f61791 2004-03-21 devnull 	sum->sign = 1;
33 b3f61791 2004-03-21 devnull 
34 b3f61791 2004-03-21 devnull 	mpnorm(sum);
35 b3f61791 2004-03-21 devnull }
36 b3f61791 2004-03-21 devnull 
37 cbeb0b26 2006-04-01 devnull /* sum = b1 + b2 */
38 b3f61791 2004-03-21 devnull void
39 b3f61791 2004-03-21 devnull mpadd(mpint *b1, mpint *b2, mpint *sum)
40 b3f61791 2004-03-21 devnull {
41 b3f61791 2004-03-21 devnull 	int sign;
42 b3f61791 2004-03-21 devnull 
43 b3f61791 2004-03-21 devnull 	if(b1->sign != b2->sign){
44 b3f61791 2004-03-21 devnull 		if(b1->sign < 0)
45 b3f61791 2004-03-21 devnull 			mpmagsub(b2, b1, sum);
46 b3f61791 2004-03-21 devnull 		else
47 b3f61791 2004-03-21 devnull 			mpmagsub(b1, b2, sum);
48 b3f61791 2004-03-21 devnull 	} else {
49 b3f61791 2004-03-21 devnull 		sign = b1->sign;
50 b3f61791 2004-03-21 devnull 		mpmagadd(b1, b2, sum);
51 b3f61791 2004-03-21 devnull 		if(sum->top != 0)
52 b3f61791 2004-03-21 devnull 			sum->sign = sign;
53 b3f61791 2004-03-21 devnull 	}
54 b3f61791 2004-03-21 devnull }