sysdeps/s390/fpu/bits/fenv.h

   1 /* Copyright (C) 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com).
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.
  19
  20  */
  21
  22 #ifndef _FENV_H
  23 # error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
  24 #endif
  25
  26 /* Define bits representing the exception.  We use the bit positions
  27    of the appropriate bits in the FPU control word.  */
  28 enum
  29   {
  30     FE_INVALID = 0x80,
  31 #define FE_INVALID      FE_INVALID
  32     FE_DIVBYZERO = 0x40,
  33 #define FE_DIVBYZERO    FE_DIVBYZERO
  34     FE_OVERFLOW = 0x20,
  35 #define FE_OVERFLOW     FE_OVERFLOW
  36     FE_UNDERFLOW = 0x10,
  37 #define FE_UNDERFLOW    FE_UNDERFLOW
  38     FE_INEXACT = 0x08
  39 #define FE_INEXACT      FE_INEXACT
  40   };
  41 /* We dont use the y bit of the DXC in the floating point control register
  42  * as glibc has no FE encoding for fe inexact incremented
  43  * or fe inexact truncated.
  44  * We currently  use the flag bits in the fpc
  45  * as these are sticky for feholdenv & feupdatenv as it is defined
  46  * in the HP Manpages.
  47  */
  48
  49
  50 #define FE_ALL_EXCEPT \
  51         (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
  52
  53 enum
  54   {
  55     FE_TONEAREST = 0,
  56 #define FE_TONEAREST    FE_TONEAREST
  57     FE_DOWNWARD = 0x3,
  58 #define FE_DOWNWARD     FE_DOWNWARD
  59     FE_UPWARD = 0x2,
  60 #define FE_UPWARD       FE_UPWARD
  61     FE_TOWARDZERO = 0x1
  62 #define FE_TOWARDZERO   FE_TOWARDZERO
  63   };
  64
  65 #define FPC_EXCEPTION_MASK_SHIFT  24
  66 #define FPC_FLAGS_SHIFT           16
  67 #define FPC_DXC_SHIFT             8
  68 #define FPC_NOT_FPU_EXCEPTION     0x300
  69
  70
  71 /* Type representing exception flags.  */
  72 typedef unsigned int fexcept_t; /* size of fpc */
  73
  74
  75 /* Type representing floating-point environment.  This function corresponds
  76    to the layout of the block written by the `fstenv'.  */
  77 typedef struct
  78 {
  79         fexcept_t fpc;
  80         void *ieee_instruction_pointer;
  81         /* failing instruction for ieee exceptions */
  82 } fenv_t;
  83
  84 /* If the default argument is used we use this value.  */
  85 #define FE_DFL_ENV      ((fenv_t *) -1)
  86
  87 #ifdef __USE_GNU
  88 /* Floating-point environment where none of the exceptions are masked.  */
  89 #define FE_NOMASK_ENV   ((fenv_t *) -2)
  90 #endif