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_private.h>
21#include <libm-alias-float.h>
22
23static const float
24TWO23[2]={
25 8.3886080000e+06, /* 0x4b000000 */
26 -8.3886080000e+06, /* 0xcb000000 */
27};
28
29float
30__nearbyintf(float x)
31{
32 fenv_t env;
33 int32_t i0,j0,sx;
34 float w,t;
35 GET_FLOAT_WORD(i0,x);
36 sx = (i0>>31)&1;
37 j0 = ((i0>>23)&0xff)-0x7f;
38 if(j0<23) {
39 if(j0<0) {
40 libc_feholdexceptf (&env);
41 w = TWO23[sx] + math_opt_barrier (x);
42 t = w-TWO23[sx];
43 math_force_eval (t);
44 libc_fesetenvf (&env);
45 GET_FLOAT_WORD(i0,t);
46 SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
47 return t;
48 }
49 } else {
50 if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
51 else return x; /* x is integral */
52 }
53 libc_feholdexceptf (&env);
54 w = TWO23[sx] + math_opt_barrier (x);
55 t = w-TWO23[sx];
56 math_force_eval (t);
57 libc_fesetenvf (&env);
58 return t;
59}
60libm_alias_float (__nearbyint, nearbyint)
61