1 | /* s_frexpf.c -- float version of s_frexp.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 | #if defined(LIBM_SCCS) && !defined(lint) |
17 | static char rcsid[] = "$NetBSD: s_frexpf.c,v 1.5 1995/05/10 20:47:26 jtc Exp $" ; |
18 | #endif |
19 | |
20 | #include <math.h> |
21 | #include <math_private.h> |
22 | #include <libm-alias-float.h> |
23 | |
24 | static const float |
25 | two25 = 3.3554432000e+07; /* 0x4c000000 */ |
26 | |
27 | float __frexpf(float x, int *eptr) |
28 | { |
29 | int32_t hx,ix; |
30 | GET_FLOAT_WORD(hx,x); |
31 | ix = 0x7fffffff&hx; |
32 | *eptr = 0; |
33 | if(ix>=0x7f800000||(ix==0)) return x + x; /* 0,inf,nan */ |
34 | if (ix<0x00800000) { /* subnormal */ |
35 | x *= two25; |
36 | GET_FLOAT_WORD(hx,x); |
37 | ix = hx&0x7fffffff; |
38 | *eptr = -25; |
39 | } |
40 | *eptr += (ix>>23)-126; |
41 | hx = (hx&0x807fffff)|0x3f000000; |
42 | SET_FLOAT_WORD(x,hx); |
43 | return x; |
44 | } |
45 | libm_alias_float (__frexp, frexp) |
46 | |