1  /* Definitions of target machine for GNU compiler, for IBM S/390
       2     Copyright (C) 1999-2023 Free Software Foundation, Inc.
       3     Contributed by Hartmut Penner (hpenner@de.ibm.com) and
       4                    Ulrich Weigand (uweigand@de.ibm.com).
       5  
       6  This file is part of GCC.
       7  
       8  GCC is free software; you can redistribute it and/or modify it under
       9  the terms of the GNU General Public License as published by the Free
      10  Software Foundation; either version 3, or (at your option) any later
      11  version.
      12  
      13  GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      14  WARRANTY; without even the implied warranty of MERCHANTABILITY or
      15  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      16  for more details.
      17  
      18  Under Section 7 of GPL version 3, you are granted additional
      19  permissions described in the GCC Runtime Library Exception, version
      20  3.1, as published by the Free Software Foundation.
      21  
      22  You should have received a copy of the GNU General Public License and
      23  a copy of the GCC Runtime Library Exception along with this program;
      24  see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
      25  <http://www.gnu.org/licenses/>.  */
      26  
      27  #ifndef __s390x__
      28  
      29  #define EXPD(fp)	(((fp.l.upper) >> 20) & 0x7FF)
      30  #define EXPONENT_BIAS	1023
      31  #define MANTISSA_BITS   52
      32  #define PRECISION       (MANTISSA_BITS + 1)
      33  #define SIGNBIT		0x80000000
      34  #define SIGN(fp)	((fp.l.upper) & SIGNBIT)
      35  #define MANTD_LL(fp)	((fp.ll & (HIDDEND_LL-1)) | HIDDEND_LL)
      36  #define FRACD_LL(fp)	(fp.ll & (HIDDEND_LL-1))
      37  #define HIDDEND_LL	((UDItype_x)1 << 52)
      38  
      39  typedef int DItype_x __attribute__ ((mode (DI)));
      40  typedef unsigned int UDItype_x __attribute__ ((mode (DI)));
      41  typedef int SItype_x __attribute__ ((mode (SI)));
      42  typedef unsigned int USItype_x __attribute__ ((mode (SI)));
      43  
      44  union double_long {
      45      double d;
      46      struct {
      47        SItype_x upper;
      48        USItype_x lower;
      49      } l;
      50      UDItype_x ll;
      51  };
      52  
      53  static __inline__ void
      54  fexceptdiv (float d, float e)
      55  {
      56    __asm__ __volatile__ ("debr %0,%1" : : "f" (d), "f" (e) );
      57  }
      58  
      59  UDItype_x __fixunsdfdi (double a1);
      60  
      61  /* convert double to unsigned int */
      62  UDItype_x
      63  __fixunsdfdi (double a1)
      64  {
      65      register union double_long dl1;
      66      register int exp;
      67      register UDItype_x l;
      68  
      69      dl1.d = a1;
      70  
      71      /* +/- 0, denormalized  */
      72      if (!EXPD (dl1))
      73        return 0;
      74  
      75      /* Negative.  */
      76      if (SIGN (dl1))
      77        { 
      78  	/* Value is <= -1.0
      79  	   C99 Annex F.4 requires an "invalid" exception to be thrown.  */
      80  	if (EXPD (dl1) >= EXPONENT_BIAS)
      81  	  fexceptdiv (0.0, 0.0);
      82  	return 0;
      83        }
      84  
      85      exp = EXPD (dl1) - EXPONENT_BIAS - MANTISSA_BITS;
      86  
      87      /* number < 1 */
      88  
      89      if (exp < -PRECISION)
      90        return 0;
      91  
      92      /* NaN */
      93  
      94      if ((EXPD(dl1) == 0x7ff) && (FRACD_LL(dl1) != 0)) /* NaN */
      95        {
      96  	/* C99 Annex F.4 requires an "invalid" exception to be thrown.  */
      97  	fexceptdiv (0.0, 0.0);
      98  	return 0x0ULL;
      99        }
     100  
     101      /* Number big number & + inf */
     102  
     103      if (exp >= 12)
     104        {
     105  	/* C99 Annex F.4 requires an "invalid" exception to be thrown.  */
     106  	fexceptdiv (0.0, 0.0);
     107  	return 0xFFFFFFFFFFFFFFFFULL;
     108        }
     109  
     110      l = MANTD_LL(dl1);
     111  
     112      /* shift down until exp < 12 or l = 0 */
     113      if (exp > 0)
     114        l <<= exp;
     115      else
     116        l >>= -exp;
     117  
     118      return l;
     119  }
     120  #endif /* !__s390x__ */