s_modff.c
1.31 KB
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/* s_modff.c -- float version of s_modf.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "math.h"
#include "math_private.h"
static const float one = 1.0;
float
modff(float x, float *iptr)
{
int32_t i0,jj0;
u_int32_t i;
GET_FLOAT_WORD(i0,x);
jj0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */
if(jj0<23) { /* integer part in x */
if(jj0<0) { /* |x|<1 */
SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */
return x;
} else {
i = (0x007fffff)>>jj0;
if((i0&i)==0) { /* x is integral */
u_int32_t ix;
*iptr = x;
GET_FLOAT_WORD(ix,x);
SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */
return x;
} else {
SET_FLOAT_WORD(*iptr,i0&(~i));
return x - *iptr;
}
}
} else { /* no fraction part */
u_int32_t ix;
*iptr = x*one;
GET_FLOAT_WORD(ix,x);
SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */
return x;
}
}