1/* s_frexpl.c -- long double version of s_frexp.c. 2 * Conversion to long double by Ulrich Drepper, 3 * Cygnus Support, drepper@cygnus.com. 4 */ 5 6/* 7 * ==================================================== 8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 9 * 10 * Developed at SunPro, a Sun Microsystems, Inc. business. 11 * Permission to use, copy, modify, and distribute this 12 * software is freely granted, provided that this notice 13 * is preserved. 14 * ==================================================== 15 */ 16 17#if defined(LIBM_SCCS) && !defined(lint) 18static char rcsid[] = "$NetBSD: $"; 19#endif 20 21/* 22 * for non-zero x 23 * x = frexpl(arg,&exp); 24 * return a long double fp quantity x such that 0.5 <= |x| <1.0 25 * and the corresponding binary exponent "exp". That is 26 * arg = x*2^exp. 27 * If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg 28 * with *exp=0. 29 */ 30 31#include <float.h> 32#include "math.h" 33#include "math_private.h" 34 35#ifdef __STDC__ 36static const long double 37#else 38static long double 39#endif 40#if LDBL_MANT_DIG == 64 41two65 = 3.68934881474191032320e+19L; /* 0x4040, 0x80000000, 0x00000000 */ 42#else 43# error "Cannot handle this MANT_DIG" 44#endif 45 46 47#ifdef __STDC__ 48 long double __frexpl(long double x, int *eptr) 49#else 50 long double __frexpl(x, eptr) 51 long double x; int *eptr; 52#endif 53{ 54 u_int32_t se, hx, ix, lx; 55 GET_LDOUBLE_WORDS(se,hx,lx,x); 56 ix = 0x7fff&se; 57 *eptr = 0; 58 if(ix==0x7fff||((ix|hx|lx)==0)) return x; /* 0,inf,nan */ 59 if (ix==0x0000) { /* subnormal */ 60 x *= two65; 61 GET_LDOUBLE_EXP(se,x); 62 ix = se&0x7fff; 63 *eptr = -65; 64 } 65 *eptr += ix-16382; 66 se = (se & 0x8000) | 0x3ffe; 67 SET_LDOUBLE_EXP(x,se); 68 return x; 69} 70weak_alias (__frexpl, frexpl) 71