bfd/cpu-m68k.c

   1 /* BFD library support routines for architectures.
   2    Copyright 1990, 1991, 1992, 1993, 1994, 1997, 1998, 2000, 2001, 2002,
   3    2003, 2004, 2006 Free Software Foundation, Inc.
   4    Hacked by Steve Chamberlain of Cygnus Support.
   5
   6    This file is part of BFD, the Binary File Descriptor library.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  21
  22 #include "bfd.h"
  23 #include "sysdep.h"
  24 #include "libbfd.h"
  25 #include "opcode/m68k.h"
  26
  27 static const bfd_arch_info_type *
  28 bfd_m68k_compatible (const bfd_arch_info_type *a,
  29                      const bfd_arch_info_type *b);
  30
  31 #define N(name, print,d,next)  \
  32 {  32, 32, 8, bfd_arch_m68k, name, "m68k",print,2,d,bfd_m68k_compatible,bfd_default_scan, next, }
  33
  34 static const bfd_arch_info_type arch_info_struct[] =
  35   {
  36     N(bfd_mach_m68000,  "m68k:68000", FALSE, &arch_info_struct[1]),
  37     N(bfd_mach_m68008,  "m68k:68008", FALSE, &arch_info_struct[2]),
  38     N(bfd_mach_m68010,  "m68k:68010", FALSE, &arch_info_struct[3]),
  39     N(bfd_mach_m68020,  "m68k:68020", FALSE, &arch_info_struct[4]),
  40     N(bfd_mach_m68030,  "m68k:68030", FALSE, &arch_info_struct[5]),
  41     N(bfd_mach_m68040,  "m68k:68040", FALSE, &arch_info_struct[6]),
  42     N(bfd_mach_m68060,  "m68k:68060", FALSE, &arch_info_struct[7]),
  43     N(bfd_mach_cpu32,   "m68k:cpu32", FALSE, &arch_info_struct[8]),
  44     N(bfd_mach_cpu32_fido, "m68k:fido", FALSE, &arch_info_struct[9]),
  45
  46     /* Various combinations of CF architecture features */
  47     N(bfd_mach_mcf_isa_a_nodiv, "m68k:isa-a:nodiv",
  48       FALSE, &arch_info_struct[10]),
  49     N(bfd_mach_mcf_isa_a, "m68k:isa-a",
  50       FALSE, &arch_info_struct[11]),
  51     N(bfd_mach_mcf_isa_a_mac, "m68k:isa-a:mac",
  52       FALSE, &arch_info_struct[12]),
  53     N(bfd_mach_mcf_isa_a_emac, "m68k:isa-a:emac",
  54       FALSE, &arch_info_struct[13]),
  55     N(bfd_mach_mcf_isa_aplus, "m68k:isa-aplus",
  56       FALSE, &arch_info_struct[14]),
  57     N(bfd_mach_mcf_isa_aplus_mac, "m68k:isa-aplus:mac",
  58       FALSE, &arch_info_struct[15]),
  59     N(bfd_mach_mcf_isa_aplus_emac, "m68k:isa-aplus:emac",
  60       FALSE, &arch_info_struct[16]),
  61     N(bfd_mach_mcf_isa_b_nousp, "m68k:isa-b:nousp",
  62       FALSE, &arch_info_struct[17]),
  63     N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:isa-b:nousp:mac",
  64       FALSE, &arch_info_struct[18]),
  65     N(bfd_mach_mcf_isa_b_nousp_emac, "m68k:isa-b:nousp:emac",
  66       FALSE, &arch_info_struct[19]),
  67     N(bfd_mach_mcf_isa_b, "m68k:isa-b",
  68       FALSE, &arch_info_struct[20]),
  69     N(bfd_mach_mcf_isa_b_mac, "m68k:isa-b:mac",
  70       FALSE, &arch_info_struct[21]),
  71     N(bfd_mach_mcf_isa_b_emac, "m68k:isa-b:emac",
  72       FALSE, &arch_info_struct[22]),
  73     N(bfd_mach_mcf_isa_b_float, "m68k:isa-b:float",
  74       FALSE, &arch_info_struct[23]),
  75     N(bfd_mach_mcf_isa_b_float_mac, "m68k:isa-b:float:mac",
  76       FALSE, &arch_info_struct[24]),
  77     N(bfd_mach_mcf_isa_b_float_emac, "m68k:isa-b:float:emac",
  78       FALSE, &arch_info_struct[25]),
  79
  80     /* Legacy names for CF architectures */
  81     N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[26]),
  82     N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[27]),
  83     N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[28]),
  84     N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[29]),
  85     N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[30]),
  86     N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[31]),
  87     N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[32]),
  88     N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
  89       FALSE, &arch_info_struct[33]),
  90     N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
  91       FALSE, &arch_info_struct[34]),
  92     N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
  93   };
  94
  95 const bfd_arch_info_type bfd_m68k_arch =
  96   N(0, "m68k", TRUE, &arch_info_struct[0]);
  97
  98 /* Table indexed by bfd_mach_arch number indicating which
  99    architectural features are supported.  */
 100 static const unsigned m68k_arch_features[] =
 101 {
 102   0,
 103   m68000|m68881|m68851,
 104   m68000|m68881|m68851,
 105   m68010|m68881|m68851,
 106   m68020|m68881|m68851,
 107   m68030|m68881|m68851,
 108   m68040|m68881|m68851,
 109   m68060|m68881|m68851,
 110   cpu32|m68881,
 111   cpu32|m68881|fido_a,
 112   mcfisa_a,
 113   mcfisa_a|mcfhwdiv,
 114   mcfisa_a|mcfhwdiv|mcfmac,
 115   mcfisa_a|mcfhwdiv|mcfemac,
 116   mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp,
 117   mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfmac,
 118   mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfemac,
 119   mcfisa_a|mcfhwdiv|mcfisa_b,
 120   mcfisa_a|mcfhwdiv|mcfisa_b|mcfmac,
 121   mcfisa_a|mcfhwdiv|mcfisa_b|mcfemac,
 122   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp,
 123   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfmac,
 124   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfemac,
 125   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat,
 126   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfmac,
 127   mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfemac,
 128 };
 129
 130 /* Return the count of bits set in MASK  */
 131 static unsigned
 132 bit_count (unsigned mask)
 133 {
 134   unsigned ix;
 135
 136   for (ix = 0; mask; ix++)
 137     /* Clear the LSB set */
 138     mask ^= mask & -mask;
 139   return ix;
 140 }
 141
 142 /* Return the architectural features supported by MACH */
 143
 144 unsigned
 145 bfd_m68k_mach_to_features (int mach)
 146 {
 147   if ((unsigned)mach
 148       >= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
 149     mach = 0;
 150   return m68k_arch_features[mach];
 151 }
 152
 153 /* Return the bfd machine that most closely represents the
 154    architectural features.  We find the machine with the smallest
 155    number of additional features.  If there is no such machine, we
 156    find the one with the smallest number of missing features.  */
 157
 158 int bfd_m68k_features_to_mach (unsigned features)
 159 {
 160   int superset = 0, subset = 0;
 161   unsigned extra = 99, missing = 99;
 162   unsigned ix;
 163
 164   for (ix = 0;
 165        ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
 166        ix++)
 167     {
 168       unsigned this_extra, this_missing;
 169
 170       if (m68k_arch_features[ix] == features)
 171         return ix;
 172       this_extra = bit_count (m68k_arch_features[ix] & ~features);
 173       if (this_extra < extra)
 174         {
 175           extra = this_extra;
 176           superset = ix;
 177         }
 178
 179       this_missing = bit_count (features & ~m68k_arch_features[ix]);
 180       if (this_missing < missing)
 181         {
 182           missing = this_missing;
 183           superset = ix;
 184         }
 185     }
 186   return superset ? superset : subset;
 187 }
 188
 189 static const bfd_arch_info_type *
 190 bfd_m68k_compatible (const bfd_arch_info_type *a,
 191                      const bfd_arch_info_type *b)
 192 {
 193   if (a->arch != b->arch)
 194     return NULL;
 195
 196   if (a->bits_per_word != b->bits_per_word)
 197     return NULL;
 198
 199   if (!a->mach)
 200     return b;
 201   if (!b->mach)
 202     return a;
 203
 204   if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
 205     /* Merge m68k machine. */
 206     return a->mach > b->mach ? a : b;
 207   else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
 208     {
 209       /* Merge the machine features.  */
 210       unsigned features = (bfd_m68k_mach_to_features (a->mach)
 211                            | bfd_m68k_mach_to_features (b->mach));
 212
 213       /* CPU32 and Coldfire are incompatible.  */
 214       if ((~features & (cpu32 | mcfisa_a)) == 0)
 215         return NULL;
 216
 217       /* ISA A+ and ISA B are incompatible.  */
 218       if ((~features & (mcfisa_aa | mcfisa_b)) == 0)
 219         return NULL;
 220
 221       /* MAC and EMAC code cannot be merged.  */
 222       if ((~features & (mcfmac | mcfemac)) == 0)
 223         return NULL;
 224
 225       return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
 226     }
 227   else
 228     /* They are incompatible.  */
 229     return NULL;
 230 }