ports/sysdeps/hppa/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 David Huggins-Daines <dhd@debian.org>
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _FENV_H
  20 # error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
  21 #endif
  22
  23 /* Define bits representing the exception.  We use the values of the
  24    appropriate enable bits in the FPU status word (which,
  25    coincidentally, are the same as the flag bits, but shifted right by
  26    27 bits).  */
  27 enum
  28 {
  29   FE_INVALID   = 1<<4, /* V */
  30 #define FE_INVALID      FE_INVALID
  31   FE_DIVBYZERO = 1<<3, /* Z */
  32 #define FE_DIVBYZERO    FE_DIVBYZERO
  33   FE_OVERFLOW  = 1<<2, /* O */
  34 #define FE_OVERFLOW     FE_OVERFLOW
  35   FE_UNDERFLOW = 1<<1, /* U */
  36 #define FE_UNDERFLOW    FE_UNDERFLOW
  37   FE_INEXACT   = 1<<0, /* I */
  38 #define FE_INEXACT      FE_INEXACT
  39 };
  40
  41 #define FE_ALL_EXCEPT \
  42         (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
  43
  44 /* The PA-RISC FPU supports all of the four defined rounding modes.
  45    We use the values of the RM field in the floating point status
  46    register for the appropriate macros.  */
  47 enum
  48   {
  49     FE_TONEAREST  = 0 << 9,
  50 #define FE_TONEAREST    FE_TONEAREST
  51     FE_TOWARDZERO = 1 << 9,
  52 #define FE_TOWARDZERO   FE_TOWARDZERO
  53     FE_UPWARD     = 2 << 9,
  54 #define FE_UPWARD       FE_UPWARD
  55     FE_DOWNWARD   = 3 << 9,
  56 #define FE_DOWNWARD     FE_DOWNWARD
  57   };
  58
  59 /* Type representing exception flags. */
  60 typedef unsigned int fexcept_t;
  61
  62 /* Type representing floating-point environment.  This structure
  63    corresponds to the layout of the status and exception words in the
  64    register file. The exception registers are never saved/stored by
  65    userspace. This structure is also not correctly aligned ever, in
  66    an ABI error we left out __aligned(8) and subsequently all of our
  67    fenv functions must accept unaligned input, align the input, and
  68    then use assembly to store fr0. This is a performance hit, but
  69    means the ABI is stable. */
  70 typedef struct
  71 {
  72   unsigned int __status_word;
  73   unsigned int __exception[7];
  74 } fenv_t;
  75
  76 /* If the default argument is used we use this value.  */
  77 #define FE_DFL_ENV ((fenv_t *) -1)
  78
  79 #ifdef __USE_GNU
  80 /* Floating-point environment where none of the exceptions are masked.  */
  81 # define FE_NOMASK_ENV  ((fenv_t *) -2)
  82 #endif