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 | |
19 | static const float |
20 | TWO23[2]={ |
21 | 8.3886080000e+06, /* 0x4b000000 */ |
22 | -8.3886080000e+06, /* 0xcb000000 */ |
23 | }; |
24 | |
25 | float |
26 | __rintf(float x) |
27 | { |
28 | int32_t i0,j0,sx; |
29 | float w,t; |
30 | GET_FLOAT_WORD(i0,x); |
31 | sx = (i0>>31)&1; |
32 | j0 = ((i0>>23)&0xff)-0x7f; |
33 | if(j0<23) { |
34 | if(j0<0) { |
35 | w = TWO23[sx]+x; |
36 | t = w-TWO23[sx]; |
37 | GET_FLOAT_WORD(i0,t); |
38 | SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31)); |
39 | return t; |
40 | } |
41 | } else { |
42 | if(j0==0x80) return x+x; /* inf or NaN */ |
43 | else return x; /* x is integral */ |
44 | } |
45 | w = TWO23[sx]+x; |
46 | return w-TWO23[sx]; |
47 | } |
48 | #ifndef __rintf |
49 | weak_alias (__rintf, rintf) |
50 | #endif |
51 | |