view libgcc/config/s390/32/_fixsfdi.c @ 55:77e2b8dfacca gcc-4.4.5

update it from 4.4.3 to 4.5.0
author ryoma <e075725@ie.u-ryukyu.ac.jp>
date Fri, 12 Feb 2010 23:39:51 +0900
parents
children 04ced10e8804
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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 EXP(fp)         (((fp.l) >> 23) & 0xFF)
#define EXCESS          126
#define SIGNBIT         0x80000000
#define SIGN(fp)        ((fp.l) & SIGNBIT)
#define HIDDEN          (1 << 23)
#define MANT(fp)        (((fp.l) & 0x7FFFFF) | HIDDEN)
#define FRAC(fp)        ((fp.l) & 0x7FFFFF)

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 float_long
  {
    float f;
    USItype_x l;
  };

DItype_x __fixsfdi (float a1);

/* convert double to int */
DItype_x
__fixsfdi (float a1)
{
    register union float_long fl1;
    register int exp;
    register DItype_x l;

    fl1.f = a1;

    /* +/- 0, denormalized */

    if (!EXP (fl1))
      return 0;

    exp = EXP (fl1) - EXCESS - 24;

    /* number < 1 */

    if (exp < -24)
      return 0;

    /* NaN */

    if ((EXP(fl1) == 0xff) && (FRAC(fl1) != 0)) /* NaN */
      return 0x8000000000000000ULL;

    /* Number big number & +/- inf */

    if (exp >= 40) {
	l = (long long)1<<63;
	if (!SIGN(fl1))
	    l--;
	return l;
    }

    l = MANT(fl1);

    if (exp > 0)
      l <<= exp;
    else
      l >>= -exp;

    return (SIGN (fl1) ? -l : l);
}