1  /* s_frexpl.c -- long double version of s_frexp.c.
       2   */
       3  
       4  /*
       5   * ====================================================
       6   * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
       7   *
       8   * Developed at SunPro, a Sun Microsystems, Inc. business.
       9   * Permission to use, copy, modify, and distribute this
      10   * software is freely granted, provided that this notice
      11   * is preserved.
      12   * ====================================================
      13   */
      14  
      15  #if defined(LIBM_SCCS) && !defined(lint)
      16  static char rcsid[] = "$NetBSD: $";
      17  #endif
      18  
      19  /*
      20   * for non-zero x
      21   *	x = frexpl(arg,&exp);
      22   * return a long double fp quantity x such that 0.5 <= |x| <1.0
      23   * and the corresponding binary exponent "exp". That is
      24   *	arg = x*2^exp.
      25   * If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg
      26   * with *exp=0.
      27   */
      28  
      29  #include <math.h>
      30  #include <math_private.h>
      31  #include <libm-alias-ldouble.h>
      32  
      33  static const _Float128
      34  two114 = L(2.0769187434139310514121985316880384E+34); /* 0x4071000000000000, 0 */
      35  
      36  _Float128 __frexpl(_Float128 x, int *eptr)
      37  {
      38  	uint64_t hx, lx, ix;
      39  	GET_LDOUBLE_WORDS64(hx,lx,x);
      40  	ix = 0x7fffffffffffffffULL&hx;
      41  	*eptr = 0;
      42  	if(ix>=0x7fff000000000000ULL||((ix|lx)==0)) return x + x;/* 0,inf,nan */
      43  	if (ix<0x0001000000000000ULL) {		/* subnormal */
      44  	    x *= two114;
      45  	    GET_LDOUBLE_MSW64(hx,x);
      46  	    ix = hx&0x7fffffffffffffffULL;
      47  	    *eptr = -114;
      48  	}
      49  	*eptr += (ix>>48)-16382;
      50  	hx = (hx&0x8000ffffffffffffULL) | 0x3ffe000000000000ULL;
      51  	SET_LDOUBLE_MSW64(x,hx);
      52  	return x;
      53  }
      54  libm_alias_ldouble (__frexp, frexp)