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/* Single precision version of nexttoward.c.
Conversion to IEEE single float by Jakub Jelinek, jj@ultra.linux.cz. */
/*
* ====================================================
* 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.
* ====================================================
*/
/* IEEE functions
* __nexttowardfd(x,y)
* return the next machine floating-point number of x in the
* direction toward y.
* This is for machines which use different binary type for double and
* long double conditionally, y is long double equal to double.
* Special cases:
*/
#include <errno.h>
#include <math.h>
#include <math_private.h>
#include <math_ldbl_opt.h>
#include <float.h>
float __nldbl_nexttowardf(float x, double y);
float __nldbl_nexttowardf(float x, double y)
{
int32_t hx,hy,ix,iy;
u_int32_t ly;
GET_FLOAT_WORD(hx,x);
EXTRACT_WORDS(hy,ly,y);
ix = hx&0x7fffffff; /* |x| */
iy = hy&0x7fffffff; /* |y| */
if((ix>0x7f800000) || /* x is nan */
((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) /* y is nan */
return x+y;
if((double) x==y) return y; /* x=y, return y */
if(ix==0) { /* x == 0 */
float u;
SET_FLOAT_WORD(x,(u_int32_t)(hy&0x80000000)|1);/* return +-minsub*/
u = math_opt_barrier (x);
u = u * u;
math_force_eval (u); /* raise underflow flag */
return x;
}
if(hx>=0) { /* x > 0 */
if(x > y) /* x -= ulp */
hx -= 1;
else /* x < y, x += ulp */
hx += 1;
} else { /* x < 0 */
if(x < y) /* x -= ulp */
hx -= 1;
else /* x > y, x += ulp */
hx += 1;
}
hy = hx&0x7f800000;
if(hy>=0x7f800000) {
float u = x+x; /* overflow */
math_force_eval (u);
__set_errno (ERANGE);
}
if(hy<0x00800000) {
float u = x*x; /* underflow */
math_force_eval (u); /* raise underflow flag */
__set_errno (ERANGE);
}
SET_FLOAT_WORD(x,hx);
return x;
}
#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_1)
compat_symbol (libm, __nldbl_nexttowardf, nexttowardf, GLIBC_2_1);
#endif
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