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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-barriers.h>
#include <math_private.h>
#include <fenv_private.h>
#include <libm-alias-float.h>
#include <math-use-builtins.h>
float
__nearbyintf(float x)
{
#if USE_NEARBYINTF_BUILTIN
return __builtin_nearbyintf (x);
#else
/* Use generic implementation. */
static const float
TWO23[2] = {
8.3886080000e+06, /* 0x4b000000 */
-8.3886080000e+06, /* 0xcb000000 */
};
fenv_t env;
int32_t i0,j0,sx;
float w,t;
GET_FLOAT_WORD(i0,x);
sx = (i0>>31)&1;
j0 = ((i0>>23)&0xff)-0x7f;
if(j0<23) {
if(j0<0) {
libc_feholdexceptf (&env);
w = TWO23[sx] + math_opt_barrier (x);
t = w-TWO23[sx];
math_force_eval (t);
libc_fesetenvf (&env);
GET_FLOAT_WORD(i0,t);
SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
return t;
}
} else {
if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
else return x; /* x is integral */
}
libc_feholdexceptf (&env);
w = TWO23[sx] + math_opt_barrier (x);
t = w-TWO23[sx];
math_force_eval (t);
libc_fesetenvf (&env);
return t;
#endif /* ! USE_NEARBYINT_BUILTIN */
}
libm_alias_float (__nearbyint, nearbyint)
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