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 <libm-alias-float.h>
23
24static const float
25TWO23[2]={
26 8.3886080000e+06, /* 0x4b000000 */
27 -8.3886080000e+06, /* 0xcb000000 */
28};
29
30float
31__nearbyintf(float x)
32{
33 fenv_t env;
34 int32_t i0,j0,sx;
35 float w,t;
36 GET_FLOAT_WORD(i0,x);
37 sx = (i0>>31)&1;
38 j0 = ((i0>>23)&0xff)-0x7f;
39 if(j0<23) {
40 if(j0<0) {
41 libc_feholdexceptf (&env);
42 w = TWO23[sx] + math_opt_barrier (x);
43 t = w-TWO23[sx];
44 math_force_eval (t);
45 libc_fesetenvf (&env);
46 GET_FLOAT_WORD(i0,t);
47 SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
48 return t;
49 }
50 } else {
51 if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
52 else return x; /* x is integral */
53 }
54 libc_feholdexceptf (&env);
55 w = TWO23[sx] + math_opt_barrier (x);
56 t = w-TWO23[sx];
57 math_force_eval (t);
58 libc_fesetenvf (&env);
59 return t;
60}
61libm_alias_float (__nearbyint, nearbyint)
62