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 | |
5 | /* |
6 | * ==================================================== |
7 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
8 | * |
9 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
10 | * Permission to use, copy, modify, and distribute this |
11 | * software is freely granted, provided that this notice |
12 | * is preserved. |
13 | * ==================================================== |
14 | */ |
15 | |
16 | #include <math.h> |
17 | #include <math_private.h> |
18 | #include <libm-alias-float.h> |
19 | |
20 | static const float |
21 | TWO23[2]={ |
22 | 8.3886080000e+06, /* 0x4b000000 */ |
23 | -8.3886080000e+06, /* 0xcb000000 */ |
24 | }; |
25 | |
26 | float |
27 | __rintf(float x) |
28 | { |
29 | int32_t i0,j0,sx; |
30 | float w,t; |
31 | GET_FLOAT_WORD(i0,x); |
32 | sx = (i0>>31)&1; |
33 | j0 = ((i0>>23)&0xff)-0x7f; |
34 | if(j0<23) { |
35 | if(j0<0) { |
36 | w = TWO23[sx]+x; |
37 | t = w-TWO23[sx]; |
38 | GET_FLOAT_WORD(i0,t); |
39 | SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31)); |
40 | return t; |
41 | } |
42 | } else { |
43 | if(j0==0x80) return x+x; /* inf or NaN */ |
44 | else return x; /* x is integral */ |
45 | } |
46 | w = TWO23[sx]+x; |
47 | return w-TWO23[sx]; |
48 | } |
49 | #ifndef __rintf |
50 | libm_alias_float (__rint, rint) |
51 | #endif |
52 | |