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/* Definitions of target machine for GNU compiler, for IBM S/390

   Copyright (C) 1999, 2000, 2001, 2007, 2008 and 2009

   Free Software Foundation, Inc.

   Contributed by Hartmut Penner (hpenner@de.ibm.com) and

                  Ulrich Weigand (uweigand@de.ibm.com).

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under

the terms of the GNU General Public License as published by the Free

Software Foundation; either version 3, or (at your option) any later

version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY

WARRANTY; without even the implied warranty of MERCHANTABILITY or

FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

for more details.

Under Section 7 of GPL version 3, you are granted additional

permissions described in the GCC Runtime Library Exception, version

3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and

a copy of the GCC Runtime Library Exception along with this program;

see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

<http://www.gnu.org/licenses/>.  */

#define EXPD(fp)           (((fp.l.i[0]) >> 16) & 0x7FFF)

#define EXPONENT_BIAS      16383

#define MANTISSA_BITS      112

#define PRECISION          (MANTISSA_BITS + 1)

#define SIGNBIT            0x80000000

#define SIGND(fp)          ((fp.l.i[0]) & SIGNBIT)

#define MANTD_HIGH_LL(fp)  ((fp.ll[0] & HIGH_LL_FRAC_MASK) | HIGH_LL_UNIT_BIT)

#define MANTD_LOW_LL(fp)   (fp.ll[1])

#define FRACD_ZERO_P(fp)   (!fp.ll[1] && !(fp.ll[0] & HIGH_LL_FRAC_MASK))

#define HIGH_LL_FRAC_BITS  48

#define HIGH_LL_UNIT_BIT   ((UDItype_x)1 << HIGH_LL_FRAC_BITS)

#define HIGH_LL_FRAC_MASK  (HIGH_LL_UNIT_BIT - 1)

typedef int DItype_x __attribute__ ((mode (DI)));

typedef unsigned int UDItype_x __attribute__ ((mode (DI)));

typedef int SItype_x __attribute__ ((mode (SI)));

typedef unsigned int USItype_x __attribute__ ((mode (SI)));

union double_long {

  long double d;

  struct {

      SItype_x i[4]; /* 32 bit parts: 0 upper ... 3 lowest */

    } l;

  UDItype_x ll[2];   /* 64 bit parts: 0 upper, 1 lower */

};

UDItype_x __fixunstfdi (long double a1);

/* convert double to unsigned int */

UDItype_x

__fixunstfdi (long double a1)

{

    register union double_long dl1;

    register int exp;

    register UDItype_x l;

    dl1.d = a1;

    /* +/- 0, denormalized, negative */

    if (!EXPD (dl1) || SIGND(dl1))

      return 0;

    /* The exponent - considered the binary point at the right end of

       the mantissa.  */

    exp = EXPD (dl1) - EXPONENT_BIAS - MANTISSA_BITS;

    /* number < 1: If the mantissa would need to be right-shifted more bits than

       its size (plus the implied one bit on the left) the result would be

       zero.  */

    if (exp <= -PRECISION)

      return 0;

    /* NaN: All exponent bits set and a nonzero fraction.  */

    if ((EXPD(dl1) == 0x7fff) && !FRACD_ZERO_P (dl1))

      return 0x0ULL;

    /* One extra bit is needed for the unit bit which is appended by

       MANTD_HIGH_LL on the left of the matissa.  */

    exp += HIGH_LL_FRAC_BITS + 1;

    /* If the result would still need a left shift it will be too large

       to be represented.  */

    if (exp > 0)

      return 0xFFFFFFFFFFFFFFFFULL;

    l = MANTD_LOW_LL (dl1) >> (HIGH_LL_FRAC_BITS + 1)

        | MANTD_HIGH_LL (dl1) << (64 - (HIGH_LL_FRAC_BITS + 1));

    return l >> -exp;

}