34 lines
595 B
C
34 lines
595 B
C
/*
|
|
(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
|
|
See the copyright notice in the ACK home directory, in the file "Copyright".
|
|
*/
|
|
|
|
/* $Header$ */
|
|
|
|
/*
|
|
SUBTRACT TWO FLOATS - SINGLE Precision (SBF 4)
|
|
*/
|
|
|
|
#include "FP_types.h"
|
|
|
|
extern _float adf4();
|
|
|
|
_float
|
|
sbf4(s2,s1)
|
|
_float s1,s2;
|
|
{
|
|
/* changing the sign directly */
|
|
/* is faster than the code: */
|
|
/* s2 = -s2 */
|
|
char unsigned *p;
|
|
|
|
if (s2 == (_float) 0) {
|
|
return s1;
|
|
}
|
|
p = (char unsigned *) &s2;
|
|
*p ^= 0x80; /* change sign of s2 */
|
|
s1 = adf4(s2,s1);
|
|
return(s1); /* add and return result */
|
|
}
|
|
|