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/* s_scalbnl.c -- long double version of s_scalbn.c.

 * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.

 */

/*

 * ====================================================

 * 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.

 * ====================================================

 */

#include "quadmath-imp.h"

static const __float128

two114 = 2.0769187434139310514121985316880384E+34Q, /* 0x4071000000000000, 0 */

twom114 = 4.8148248609680896326399448564623183E-35Q, /* 0x3F8D000000000000, 0 */

huge   = 1.0E+4900Q,

tiny   = 1.0E-4900Q;

__float128

scalbnq (__float128 x, int n)

{

        int64_t k,hx,lx;

        GET_FLT128_WORDS64(hx,lx,x);

        k = (hx>>48)&0x7fff;            /* extract exponent */

        if (k==0) {                              /* 0 or subnormal x */

            if ((lx|(hx&0x7fffffffffffffffULL))==0) return x; /* +-0 */

            x *= two114;

            GET_FLT128_MSW64(hx,x);

            k = ((hx>>48)&0x7fff) - 114;

        }

        if (k==0x7fff) return x+x;              /* NaN or Inf */

        k = k+n;

        if (n> 50000 || k > 0x7ffe)

          return huge*copysignq(huge,x); /* overflow  */

        if (n< -50000) return tiny*copysignq(tiny,x); /*underflow*/

        if (k > 0)                               /* normal result */

            {SET_FLT128_MSW64(x,(hx&0x8000ffffffffffffULL)|(k<<48)); return x;}

        if (k <= -114)

          return tiny*copysignq(tiny,x);        /*underflow*/

        k += 114;                               /* subnormal result */

        SET_FLT128_MSW64(x,(hx&0x8000ffffffffffffULL)|(k<<48));

        return x*twom114;

}