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 #include <sys/cdefs.h> 17 #if defined(LIBM_SCCS) && !defined(lint) 18 __RCSID("$NetBSD: s_frexpf.c,v 1.10 2007/08/21 20:12:27 drochner Exp $"); 19 #endif 20 21 #include "math.h" 22 #include "math_private.h" 23 24 static const float 25 two25 = 3.3554432000e+07; /* 0x4c000000 */ 26 27 float 28 frexpf(float x, int *eptr) 29 { 30 int32_t hx,ix; 31 GET_FLOAT_WORD(hx,x); 32 ix = 0x7fffffff&hx; 33 *eptr = 0; 34 if(ix>=0x7f800000||(ix==0)) return x; /* 0,inf,nan */ 35 if (ix<0x00800000) { /* subnormal */ 36 x *= two25; 37 GET_FLOAT_WORD(hx,x); 38 ix = hx&0x7fffffff; 39 *eptr = -25; 40 } 41 *eptr += (ix>>23)-126; 42 hx = (hx&0x807fffff)|0x3f000000; 43 SET_FLOAT_WORD(x,hx); 44 return x; 45 } 46