1 /* sf_frexp.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 "fdlibm.h" 17 18 #ifdef __STDC__ 19 static const float 20 #else 21 static float 22 #endif 23 two25 = 3.3554432000e+07; /* 0x4c000000 */ 24 25 #ifdef __STDC__ frexpf(float x,int * eptr)26 float frexpf(float x, int *eptr) 27 #else 28 float frexpf(x, eptr) 29 float x; int *eptr; 30 #endif 31 { 32 __int32_t hx, ix; 33 GET_FLOAT_WORD(hx,x); 34 ix = 0x7fffffff&hx; 35 *eptr = 0; 36 if(!FLT_UWORD_IS_FINITE(ix)||FLT_UWORD_IS_ZERO(ix)) return x; /* 0,inf,nan */ 37 if (FLT_UWORD_IS_SUBNORMAL(ix)) { /* subnormal */ 38 x *= two25; 39 GET_FLOAT_WORD(hx,x); 40 ix = hx&0x7fffffff; 41 *eptr = -25; 42 } 43 *eptr += (ix>>23)-126; 44 hx = (hx&0x807fffff)|0x3f000000; 45 SET_FLOAT_WORD(x,hx); 46 return x; 47 } 48 49 #ifdef _DOUBLE_IS_32BITS 50 51 #ifdef __STDC__ frexp(double x,int * eptr)52 double frexp(double x, int *eptr) 53 #else 54 double frexp(x, eptr) 55 double x; int *eptr; 56 #endif 57 { 58 return (double) frexpf((float) x, eptr); 59 } 60 61 #endif /* defined(_DOUBLE_IS_32BITS) */ 62