libgcc/soft-fp/soft-fp.h

   1 /* Software floating-point emulation.
   2    Copyright (C) 1997,1998,1999,2000,2002,2003,2005,2006,2007,2012
   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    In addition to the permissions in the GNU Lesser General Public
  16    License, the Free Software Foundation gives you unlimited
  17    permission to link the compiled version of this file into
  18    combinations with other programs, and to distribute those
  19    combinations without any restriction coming from the use of this
  20    file.  (The Lesser General Public License restrictions do apply in
  21    other respects; for example, they cover modification of the file,
  22    and distribution when not linked into a combine executable.)
  23
  24    The GNU C Library is distributed in the hope that it will be useful,
  25    but WITHOUT ANY WARRANTY; without even the implied warranty of
  26    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  27    Lesser General Public License for more details.
  28
  29    You should have received a copy of the GNU Lesser General Public
  30    License along with the GNU C Library; if not, see
  31    <http://www.gnu.org/licenses/>.  */
  32
  33 #ifndef SOFT_FP_H
  34 #define SOFT_FP_H
  35
  36 #ifdef _LIBC
  37 #include <sfp-machine.h>
  38 #else
  39 #include "sfp-machine.h"
  40 #endif
  41
  42 /* Allow sfp-machine to have its own byte order definitions. */
  43 #ifndef __BYTE_ORDER
  44 #ifdef _LIBC
  45 #include <endian.h>
  46 #else
  47 #error "endianness not defined by sfp-machine.h"
  48 #endif
  49 #endif
  50
  51 #define _FP_WORKBITS            3
  52 #define _FP_WORK_LSB            ((_FP_W_TYPE)1 << 3)
  53 #define _FP_WORK_ROUND          ((_FP_W_TYPE)1 << 2)
  54 #define _FP_WORK_GUARD          ((_FP_W_TYPE)1 << 1)
  55 #define _FP_WORK_STICKY         ((_FP_W_TYPE)1 << 0)
  56
  57 #ifndef FP_RND_NEAREST
  58 # define FP_RND_NEAREST         0
  59 # define FP_RND_ZERO            1
  60 # define FP_RND_PINF            2
  61 # define FP_RND_MINF            3
  62 #endif
  63 #ifndef FP_ROUNDMODE
  64 # define FP_ROUNDMODE           FP_RND_NEAREST
  65 #endif
  66
  67 /* By default don't care about exceptions. */
  68 #ifndef FP_EX_INVALID
  69 #define FP_EX_INVALID           0
  70 #endif
  71 #ifndef FP_EX_OVERFLOW
  72 #define FP_EX_OVERFLOW          0
  73 #endif
  74 #ifndef FP_EX_UNDERFLOW
  75 #define FP_EX_UNDERFLOW         0
  76 #endif
  77 #ifndef FP_EX_DIVZERO
  78 #define FP_EX_DIVZERO           0
  79 #endif
  80 #ifndef FP_EX_INEXACT
  81 #define FP_EX_INEXACT           0
  82 #endif
  83 #ifndef FP_EX_DENORM
  84 #define FP_EX_DENORM            0
  85 #endif
  86
  87 /* _FP_STRUCT_LAYOUT may be defined as an attribute to determine the
  88    struct layout variant used for structures where bit-fields are used
  89    to access specific parts of binary floating-point numbers.  This is
  90    required for systems where the default ABI uses struct layout with
  91    differences in how consecutive bit-fields are laid out from the
  92    default expected by soft-fp.  */
  93 #ifndef _FP_STRUCT_LAYOUT
  94 #define _FP_STRUCT_LAYOUT
  95 #endif
  96
  97 #ifdef _FP_DECL_EX
  98 #define FP_DECL_EX                                      \
  99   int _fex = 0;                                         \
 100   _FP_DECL_EX
 101 #else
 102 #define FP_DECL_EX int _fex = 0
 103 #endif
 104
 105 #ifndef FP_INIT_ROUNDMODE
 106 #define FP_INIT_ROUNDMODE do {} while (0)
 107 #endif
 108
 109 #ifndef FP_HANDLE_EXCEPTIONS
 110 #define FP_HANDLE_EXCEPTIONS do {} while (0)
 111 #endif
 112
 113 #ifndef FP_INHIBIT_RESULTS
 114 /* By default we write the results always.
 115  * sfp-machine may override this and e.g.
 116  * check if some exceptions are unmasked
 117  * and inhibit it in such a case.
 118  */
 119 #define FP_INHIBIT_RESULTS 0
 120 #endif
 121
 122 #define FP_SET_EXCEPTION(ex)                            \
 123   _fex |= (ex)
 124
 125 #define FP_UNSET_EXCEPTION(ex)                          \
 126   _fex &= ~(ex)
 127
 128 #define FP_CLEAR_EXCEPTIONS                             \
 129   _fex = 0
 130
 131 #define _FP_ROUND_NEAREST(wc, X)                        \
 132 do {                                                    \
 133     if ((_FP_FRAC_LOW_##wc(X) & 15) != _FP_WORK_ROUND)  \
 134       _FP_FRAC_ADDI_##wc(X, _FP_WORK_ROUND);            \
 135 } while (0)
 136
 137 #define _FP_ROUND_ZERO(wc, X)           (void)0
 138
 139 #define _FP_ROUND_PINF(wc, X)                           \
 140 do {                                                    \
 141     if (!X##_s && (_FP_FRAC_LOW_##wc(X) & 7))           \
 142       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
 143 } while (0)
 144
 145 #define _FP_ROUND_MINF(wc, X)                           \
 146 do {                                                    \
 147     if (X##_s && (_FP_FRAC_LOW_##wc(X) & 7))            \
 148       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
 149 } while (0)
 150
 151 #define _FP_ROUND(wc, X)                        \
 152 do {                                            \
 153         if (_FP_FRAC_LOW_##wc(X) & 7)           \
 154           FP_SET_EXCEPTION(FP_EX_INEXACT);      \
 155         switch (FP_ROUNDMODE)                   \
 156         {                                       \
 157           case FP_RND_NEAREST:                  \
 158             _FP_ROUND_NEAREST(wc,X);            \
 159             break;                              \
 160           case FP_RND_ZERO:                     \
 161             _FP_ROUND_ZERO(wc,X);               \
 162             break;                              \
 163           case FP_RND_PINF:                     \
 164             _FP_ROUND_PINF(wc,X);               \
 165             break;                              \
 166           case FP_RND_MINF:                     \
 167             _FP_ROUND_MINF(wc,X);               \
 168             break;                              \
 169         }                                       \
 170 } while (0)
 171
 172 #define FP_CLS_NORMAL           0
 173 #define FP_CLS_ZERO             1
 174 #define FP_CLS_INF              2
 175 #define FP_CLS_NAN              3
 176
 177 #define _FP_CLS_COMBINE(x,y)    (((x) << 2) | (y))
 178
 179 #include "op-1.h"
 180 #include "op-2.h"
 181 #include "op-4.h"
 182 #include "op-8.h"
 183 #include "op-common.h"
 184
 185 /* Sigh.  Silly things longlong.h needs.  */
 186 #define UWtype          _FP_W_TYPE
 187 #define W_TYPE_SIZE     _FP_W_TYPE_SIZE
 188
 189 typedef int QItype __attribute__((mode(QI)));
 190 typedef int SItype __attribute__((mode(SI)));
 191 typedef int DItype __attribute__((mode(DI)));
 192 typedef unsigned int UQItype __attribute__((mode(QI)));
 193 typedef unsigned int USItype __attribute__((mode(SI)));
 194 typedef unsigned int UDItype __attribute__((mode(DI)));
 195 #if _FP_W_TYPE_SIZE == 32
 196 typedef unsigned int UHWtype __attribute__((mode(HI)));
 197 #elif _FP_W_TYPE_SIZE == 64
 198 typedef USItype UHWtype;
 199 #endif
 200
 201 #ifndef CMPtype
 202 #define CMPtype         int
 203 #endif
 204
 205 #define SI_BITS         (__CHAR_BIT__ * (int)sizeof(SItype))
 206 #define DI_BITS         (__CHAR_BIT__ * (int)sizeof(DItype))
 207
 208 #ifndef umul_ppmm
 209 #ifdef _LIBC
 210 #include <stdlib/longlong.h>
 211 #else
 212 #include "longlong.h"
 213 #endif
 214 #endif
 215
 216 #ifdef _LIBC
 217 #include <stdlib.h>
 218 #else
 219 extern void abort (void);
 220 #endif
 221
 222 #endif