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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 (__glibc_unlikely (j0 == 0x80))
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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