| 0,0 → 1,54 |
|---|
| /* Copyright (C) 1994 DJ Delorie, see COPYING.DJ for details */ |
| /* s_frexpf.c -- float version of s_frexp.c. |
| * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
| */ |
| |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #if defined(LIBM_SCCS) && !defined(lint) |
| static char rcsid[] = "$Id: s_frexpf.c,v 1.2 1994/08/18 23:06:51 jtc Exp $"; |
| #endif |
| |
| #include "math.h" |
| #include "math_private.h" |
| |
| #ifdef __STDC__ |
| static const float |
| #else |
| static float |
| #endif |
| one = 1.0000000000e+00, /* 0x3F800000 */ |
| two25 = 3.3554432000e+07; /* 0x4c000000 */ |
| |
| #ifdef __STDC__ |
| float frexpf(float x, int *eptr) |
| #else |
| float frexpf(x, eptr) |
| float x; int *eptr; |
| #endif |
| { |
| int32_t hx,ix; |
| GET_FLOAT_WORD(hx,x); |
| ix = 0x7fffffff&hx; |
| *eptr = 0; |
| if(ix>=0x7f800000||(ix==0)) return x; /* 0,inf,nan */ |
| if (ix<0x00800000) { /* subnormal */ |
| x *= two25; |
| GET_FLOAT_WORD(hx,x); |
| ix = hx&0x7fffffff; |
| *eptr = -25; |
| } |
| *eptr += (ix>>23)-126; |
| hx = (hx&0x807fffff)|0x3f000000; |
| *(int*)&x = hx; |
| return x; |
| } |