soft-fp/soft-fp.h

   1 /* Software floating-point emulation.
   2    Copyright (C) 1997,1998,1999,2000,2002,2003,2005,2006
   3         Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Richard Henderson (rth@cygnus.com),
   6                   Jakub Jelinek (jj@ultra.linux.cz),
   7                   David S. Miller (davem@redhat.com) and
   8                   Peter Maydell (pmaydell@chiark.greenend.org.uk).
   9
  10    The GNU C Library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 2.1 of the License, or (at your option) any later version.
  14
  15    The GNU C Library is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with the GNU C Library; if not, write to the Free
  22    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  23    02111-1307 USA.  */
  24
  25 #ifndef SOFT_FP_H
  26 #define SOFT_FP_H
  27
  28 #ifdef _LIBC
  29 #include <sfp-machine.h>
  30 #else
  31 #include "sfp-machine.h"
  32 #endif
  33
  34 /* Allow sfp-machine to have its own byte order definitions. */
  35 #ifndef __BYTE_ORDER
  36 #ifdef _LIBC
  37 #include <endian.h>
  38 #else
  39 #error "endianness not defined by sfp-machine.h"
  40 #endif
  41 #endif
  42
  43 #define _FP_WORKBITS            3
  44 #define _FP_WORK_LSB            ((_FP_W_TYPE)1 << 3)
  45 #define _FP_WORK_ROUND          ((_FP_W_TYPE)1 << 2)
  46 #define _FP_WORK_GUARD          ((_FP_W_TYPE)1 << 1)
  47 #define _FP_WORK_STICKY         ((_FP_W_TYPE)1 << 0)
  48
  49 #ifndef FP_RND_NEAREST
  50 # define FP_RND_NEAREST         0
  51 # define FP_RND_ZERO            1
  52 # define FP_RND_PINF            2
  53 # define FP_RND_MINF            3
  54 #endif
  55 #ifndef FP_ROUNDMODE
  56 # define FP_ROUNDMODE           FP_RND_NEAREST
  57 #endif
  58
  59 /* By default don't care about exceptions. */
  60 #ifndef FP_EX_INVALID
  61 #define FP_EX_INVALID           0
  62 #endif
  63 #ifndef FP_EX_OVERFLOW
  64 #define FP_EX_OVERFLOW          0
  65 #endif
  66 #ifndef FP_EX_UNDERFLOW
  67 #define FP_EX_UNDERFLOW         0
  68 #endif
  69 #ifndef FP_EX_DIVZERO
  70 #define FP_EX_DIVZERO           0
  71 #endif
  72 #ifndef FP_EX_INEXACT
  73 #define FP_EX_INEXACT           0
  74 #endif
  75 #ifndef FP_EX_DENORM
  76 #define FP_EX_DENORM            0
  77 #endif
  78
  79 #ifdef _FP_DECL_EX
  80 #define FP_DECL_EX                                      \
  81   int _fex = 0;                                         \
  82   _FP_DECL_EX
  83 #else
  84 #define FP_DECL_EX int _fex = 0
  85 #endif
  86
  87 #ifndef FP_INIT_ROUNDMODE
  88 #define FP_INIT_ROUNDMODE do {} while (0)
  89 #endif
  90
  91 #ifndef FP_HANDLE_EXCEPTIONS
  92 #define FP_HANDLE_EXCEPTIONS do {} while (0)
  93 #endif
  94
  95 #ifndef FP_INHIBIT_RESULTS
  96 /* By default we write the results always.
  97  * sfp-machine may override this and e.g.
  98  * check if some exceptions are unmasked
  99  * and inhibit it in such a case.
 100  */
 101 #define FP_INHIBIT_RESULTS 0
 102 #endif
 103
 104 #define FP_SET_EXCEPTION(ex)                            \
 105   _fex |= (ex)
 106
 107 #define FP_UNSET_EXCEPTION(ex)                          \
 108   _fex &= ~(ex)
 109
 110 #define FP_CLEAR_EXCEPTIONS                             \
 111   _fex = 0
 112
 113 #define _FP_ROUND_NEAREST(wc, X)                        \
 114 do {                                                    \
 115     if ((_FP_FRAC_LOW_##wc(X) & 15) != _FP_WORK_ROUND)  \
 116       _FP_FRAC_ADDI_##wc(X, _FP_WORK_ROUND);            \
 117 } while (0)
 118
 119 #define _FP_ROUND_ZERO(wc, X)           (void)0
 120
 121 #define _FP_ROUND_PINF(wc, X)                           \
 122 do {                                                    \
 123     if (!X##_s && (_FP_FRAC_LOW_##wc(X) & 7))           \
 124       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
 125 } while (0)
 126
 127 #define _FP_ROUND_MINF(wc, X)                           \
 128 do {                                                    \
 129     if (X##_s && (_FP_FRAC_LOW_##wc(X) & 7))            \
 130       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
 131 } while (0)
 132
 133 #define _FP_ROUND(wc, X)                        \
 134 do {                                            \
 135         if (_FP_FRAC_LOW_##wc(X) & 7)           \
 136           FP_SET_EXCEPTION(FP_EX_INEXACT);      \
 137         switch (FP_ROUNDMODE)                   \
 138         {                                       \
 139           case FP_RND_NEAREST:                  \
 140             _FP_ROUND_NEAREST(wc,X);            \
 141             break;                              \
 142           case FP_RND_ZERO:                     \
 143             _FP_ROUND_ZERO(wc,X);               \
 144             break;                              \
 145           case FP_RND_PINF:                     \
 146             _FP_ROUND_PINF(wc,X);               \
 147             break;                              \
 148           case FP_RND_MINF:                     \
 149             _FP_ROUND_MINF(wc,X);               \
 150             break;                              \
 151         }                                       \
 152 } while (0)
 153
 154 #define FP_CLS_NORMAL           0
 155 #define FP_CLS_ZERO             1
 156 #define FP_CLS_INF              2
 157 #define FP_CLS_NAN              3
 158
 159 #define _FP_CLS_COMBINE(x,y)    (((x) << 2) | (y))
 160
 161 #include "op-1.h"
 162 #include "op-2.h"
 163 #include "op-4.h"
 164 #include "op-8.h"
 165 #include "op-common.h"
 166
 167 /* Sigh.  Silly things longlong.h needs.  */
 168 #define UWtype          _FP_W_TYPE
 169 #define W_TYPE_SIZE     _FP_W_TYPE_SIZE
 170
 171 typedef int QItype __attribute__((mode(QI)));
 172 typedef int SItype __attribute__((mode(SI)));
 173 typedef int DItype __attribute__((mode(DI)));
 174 typedef unsigned int UQItype __attribute__((mode(QI)));
 175 typedef unsigned int USItype __attribute__((mode(SI)));
 176 typedef unsigned int UDItype __attribute__((mode(DI)));
 177 #if _FP_W_TYPE_SIZE == 32
 178 typedef unsigned int UHWtype __attribute__((mode(HI)));
 179 #elif _FP_W_TYPE_SIZE == 64
 180 typedef USItype UHWtype;
 181 #endif
 182
 183 #define SI_BITS         (__CHAR_BIT__ * (int)sizeof(SItype))
 184 #define DI_BITS         (__CHAR_BIT__ * (int)sizeof(DItype))
 185
 186 #ifndef umul_ppmm
 187 #ifdef _LIBC
 188 #include <stdlib/longlong.h>
 189 #else
 190 #include "longlong.h"
 191 #endif
 192 #endif
 193
 194 #ifdef _LIBC
 195 #include <stdlib.h>
 196 #else
 197 extern void abort (void);
 198 #endif
 199
 200 #endif