1/* s_rintf.c -- float version of s_rint.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4/* Adapted for use as nearbyint by Ulrich Drepper <drepper@cygnus.com>. */
5
6/*
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 *
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
13 * is preserved.
14 * ====================================================
15 */
16
17
18#include <fenv.h>
19#include <math.h>
20#include <math-barriers.h>
21#include <math_private.h>
22#include <fenv_private.h>
23#include <libm-alias-float.h>
24
25static const float
26TWO23[2]={
27 8.3886080000e+06, /* 0x4b000000 */
28 -8.3886080000e+06, /* 0xcb000000 */
29};
30
31float
32__nearbyintf(float x)
33{
34 fenv_t env;
35 int32_t i0,j0,sx;
36 float w,t;
37 GET_FLOAT_WORD(i0,x);
38 sx = (i0>>31)&1;
39 j0 = ((i0>>23)&0xff)-0x7f;
40 if(j0<23) {
41 if(j0<0) {
42 libc_feholdexceptf (&env);
43 w = TWO23[sx] + math_opt_barrier (x);
44 t = w-TWO23[sx];
45 math_force_eval (t);
46 libc_fesetenvf (&env);
47 GET_FLOAT_WORD(i0,t);
48 SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
49 return t;
50 }
51 } else {
52 if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
53 else return x; /* x is integral */
54 }
55 libc_feholdexceptf (&env);
56 w = TWO23[sx] + math_opt_barrier (x);
57 t = w-TWO23[sx];
58 math_force_eval (t);
59 libc_fesetenvf (&env);
60 return t;
61}
62libm_alias_float (__nearbyint, nearbyint)
63