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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
* nexttowardf(x,y)
* return the next machine floating-point number of x in the
* direction toward y.
* This is for machines which use the same binary type for double and
* long double.
* Special cases:
*/
#include <math.h>
#include "math_private.h"
#include <float.h>
#ifdef __STDC__
float __nexttowardf(float x, long double y)
#else
float __nexttowardf(x,y)
float x;
long double y;
#endif
{
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((long double) x==y) return y; /* x=y, return y */
if(ix==0) { /* x == 0 */
float x2;
SET_FLOAT_WORD(x,(u_int32_t)(hy&0x80000000)|1);/* return +-minsub*/
x2 = x*x;
if(x2==x) return x2; else return x; /* raise underflow flag */
}
if(hx>=0) { /* x > 0 */
if(hy<0||(ix>>23)>(iy>>20)-0x380
|| ((ix>>23)==(iy>>20)-0x380
&& (ix&0x7fffff)>(((hy<<3)|(ly>>29))&0x7fffff))) /* x > y, x -= ulp */
hx -= 1;
else /* x < y, x += ulp */
hx += 1;
} else { /* x < 0 */
if(hy>=0||(ix>>23)>(iy>>20)-0x380
|| ((ix>>23)==(iy>>20)-0x380
&& (ix&0x7fffff)>(((hy<<3)|(ly>>29))&0x7fffff))) /* x < y, x -= ulp */
hx -= 1;
else /* x > y, x += ulp */
hx += 1;
}
hy = hx&0x7f800000;
if(hy>=0x7f800000) {
x = x+x; /* overflow */
if (FLT_EVAL_METHOD != 0)
/* Force conversion to float. */
asm ("" : "=m"(x) : "m"(x));
return x;
}
if(hy<0x00800000) { /* underflow */
float x2 = x*x;
if(x2!=x) { /* raise underflow flag */
SET_FLOAT_WORD(x2,hx);
return x2;
}
}
SET_FLOAT_WORD(x,hx);
return x;
}
weak_alias (__nexttowardf, nexttowardf)
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