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/* s_modfl.c -- long double version of s_modf.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 one = 1.0;

__float128

modfq (__float128 x, __float128 *iptr)

{

        int64_t i0,i1,j0;

        uint64_t i;

        GET_FLT128_WORDS64(i0,i1,x);

        j0 = ((i0>>48)&0x7fff)-0x3fff;  /* exponent of x */

        if(j0<48) {                     /* integer part in high x */

            if(j0<0) {                   /* |x|<1 */

                /* *iptr = +-0 */

                SET_FLT128_WORDS64(*iptr,i0&0x8000000000000000ULL,0);

                return x;

            } else {

                i = (0x0000ffffffffffffLL)>>j0;

                if(((i0&i)|i1)==0) {             /* x is integral */

                    *iptr = x;

                    /* return +-0 */

                    SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0);

                    return x;

                } else {

                    SET_FLT128_WORDS64(*iptr,i0&(~i),0);

                    return x - *iptr;

                }

            }

        } else if (j0>111) {            /* no fraction part */

            *iptr = x*one;

            /* We must handle NaNs separately.  */

            if (j0 == 0x4000 && ((i0 & 0x0000ffffffffffffLL) | i1))

              return x*one;

            /* return +-0 */

            SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0);

            return x;

        } else {                        /* fraction part in low x */

            i = -1ULL>>(j0-48);

            if((i1&i)==0) {              /* x is integral */

                *iptr = x;

                /* return +-0 */

                SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0);

                return x;

            } else {

                SET_FLT128_WORDS64(*iptr,i0,i1&(~i));

                return x - *iptr;

            }

        }

}