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/* s_rintf.c -- float version of s_rint.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/* Adapted for use as nearbyint by Ulrich Drepper <drepper@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 <fenv.h>
#include "math.h"
#include "math_private.h"
static const float
TWO23[2]={
8.3886080000e+06, /* 0x4b000000 */
-8.3886080000e+06, /* 0xcb000000 */
};
float
__nearbyintf(float x)
{
fenv_t env;
int32_t i0,j0,sx;
u_int32_t i,i1;
float w,t;
GET_FLOAT_WORD(i0,x);
sx = (i0>>31)&1;
j0 = ((i0>>23)&0xff)-0x7f;
if(j0<23) {
if(j0<0) {
if((i0&0x7fffffff)==0) return x;
i1 = (i0&0x07fffff);
i0 &= 0xfff00000;
i0 |= ((i1|-i1)>>9)&0x400000;
SET_FLOAT_WORD(x,i0);
libc_feholdexceptf (&env);
w = TWO23[sx]+x;
t = w-TWO23[sx];
libc_fesetenvf (&env);
GET_FLOAT_WORD(i0,t);
SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
return t;
} else {
i = (0x007fffff)>>j0;
if((i0&i)==0) return x; /* x is integral */
i>>=1;
if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0);
}
} else {
if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
else return x; /* x is integral */
}
SET_FLOAT_WORD(x,i0);
libc_feholdexceptf (&env);
w = TWO23[sx]+x;
t = w-TWO23[sx];
libc_fesetenvf (&env);
return t;
}
weak_alias (__nearbyintf, nearbyintf)
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