56 lines
1.1 KiB
C
56 lines
1.1 KiB
C
/*
|
|
(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
|
|
See the copyright notice in the ACK home directory, in the file "Copyright".
|
|
*/
|
|
|
|
/* $Header$ */
|
|
|
|
/*
|
|
ADD TWO FLOATS - DOUBLE (ADF 8)
|
|
*/
|
|
|
|
#include "FP_types.h"
|
|
|
|
_double
|
|
adf8(s2,s1)
|
|
_double s1,s2;
|
|
{
|
|
EXTEND e1,e2;
|
|
int swap;
|
|
|
|
if (s1.__double[0] == 0 && s1.__double[1] == 0) {
|
|
s1 = s2;
|
|
return s1;
|
|
}
|
|
if (s2.__double[0] == 0 && s2.__double[1] == 0) {
|
|
return s1;
|
|
}
|
|
|
|
extend(&s1,&e1,sizeof(_double));
|
|
extend(&s2,&e2,sizeof(_double));
|
|
/* adjust mantissas to equal powers */
|
|
if (e1.sign ^ e2.sign) { /* signs are different */
|
|
/* determine which is largest number */
|
|
swap = (e2.exp > e1.exp) ? 1 : (e2.exp < e1.exp) ? 0 :
|
|
(e2.m1 > e1.m1 ) ? 1 : (e2.m1 < e1.m1 ) ? 0 :
|
|
(e2.m2 > e1.m2 ) ? 1 : 0;
|
|
/* adjust mantissas to equal powers */
|
|
sft_ext(&e1,&e2);
|
|
/* subtract the extended formats */
|
|
if (swap) { /* &e2 is the largest number */
|
|
sub_ext(&e2,&e1);
|
|
e1 = e2;
|
|
}
|
|
else {
|
|
sub_ext(&e1,&e2);
|
|
}
|
|
}
|
|
else {
|
|
/* adjust mantissas to equal powers */
|
|
sft_ext(&e1,&e2);
|
|
add_ext(&e1,&e2);
|
|
}
|
|
compact(&e1,&s1,sizeof(_double));
|
|
return(s1);
|
|
}
|