bfd/cpu-arm.c

   1 /* BFD support for the ARM processor
   2    Copyright 1994, 1997, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2009
   3    Free Software Foundation, Inc.
   4    Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
   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 3 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,
  21    MA 02110-1301, USA.  */
  22
  23 #include "sysdep.h"
  24 #include "bfd.h"
  25 #include "libbfd.h"
  26 #include "libiberty.h"
  27
  28 /* This routine is provided two arch_infos and works out which ARM
  29    machine which would be compatible with both and returns a pointer
  30    to its info structure.  */
  31
  32 static const bfd_arch_info_type *
  33 compatible (const bfd_arch_info_type *a, const bfd_arch_info_type *b)
  34 {
  35   /* If a & b are for different architecture we can do nothing.  */
  36   if (a->arch != b->arch)
  37       return NULL;
  38
  39   /* If a & b are for the same machine then all is well.  */
  40   if (a->mach == b->mach)
  41     return a;
  42
  43   /* Otherwise if either a or b is the 'default' machine
  44      then it can be polymorphed into the other.  */
  45   if (a->the_default)
  46     return b;
  47
  48   if (b->the_default)
  49     return a;
  50
  51   /* So far all newer ARM architecture cores are
  52      supersets of previous cores.  */
  53   if (a->mach < b->mach)
  54     return b;
  55   else if (a->mach > b->mach)
  56     return a;
  57
  58   /* Never reached!  */
  59   return NULL;
  60 }
  61
  62 static struct
  63 {
  64   unsigned int mach;
  65   char *       name;
  66 }
  67 processors[] =
  68 {
  69   { bfd_mach_arm_2,  "arm2"     },
  70   { bfd_mach_arm_2a, "arm250"   },
  71   { bfd_mach_arm_2a, "arm3"     },
  72   { bfd_mach_arm_3,  "arm6"     },
  73   { bfd_mach_arm_3,  "arm60"    },
  74   { bfd_mach_arm_3,  "arm600"   },
  75   { bfd_mach_arm_3,  "arm610"   },
  76   { bfd_mach_arm_3,  "arm7"     },
  77   { bfd_mach_arm_3,  "arm710"   },
  78   { bfd_mach_arm_3,  "arm7500"  },
  79   { bfd_mach_arm_3,  "arm7d"    },
  80   { bfd_mach_arm_3,  "arm7di"   },
  81   { bfd_mach_arm_3M, "arm7dm"   },
  82   { bfd_mach_arm_3M, "arm7dmi"  },
  83   { bfd_mach_arm_4T, "arm7tdmi" },
  84   { bfd_mach_arm_4,  "arm8"     },
  85   { bfd_mach_arm_4,  "arm810"   },
  86   { bfd_mach_arm_4,  "arm9"     },
  87   { bfd_mach_arm_4,  "arm920"   },
  88   { bfd_mach_arm_4T, "arm920t"  },
  89   { bfd_mach_arm_4T, "arm9tdmi" },
  90   { bfd_mach_arm_4,  "sa1"      },
  91   { bfd_mach_arm_4,  "strongarm"},
  92   { bfd_mach_arm_4,  "strongarm110" },
  93   { bfd_mach_arm_4,  "strongarm1100" },
  94   { bfd_mach_arm_XScale, "xscale" },
  95   { bfd_mach_arm_ep9312, "ep9312" },
  96   { bfd_mach_arm_iWMMXt, "iwmmxt" },
  97   { bfd_mach_arm_iWMMXt2, "iwmmxt2" }
  98 };
  99
 100 static bfd_boolean
 101 scan (const struct bfd_arch_info *info, const char *string)
 102 {
 103   int  i;
 104
 105   /* First test for an exact match.  */
 106   if (strcasecmp (string, info->printable_name) == 0)
 107     return TRUE;
 108
 109   /* Next check for a processor name instead of an Architecture name.  */
 110   for (i = sizeof (processors) / sizeof (processors[0]); i--;)
 111     {
 112       if (strcasecmp (string, processors [i].name) == 0)
 113         break;
 114     }
 115
 116   if (i != -1 && info->mach == processors [i].mach)
 117     return TRUE;
 118
 119   /* Finally check for the default architecture.  */
 120   if (strcasecmp (string, "arm") == 0)
 121     return info->the_default;
 122
 123   return FALSE;
 124 }
 125
 126 #define N(number, print, default, next)  \
 127 {  32, 32, 8, bfd_arch_arm, number, "arm", print, 4, default, compatible, scan, next }
 128
 129 static const bfd_arch_info_type arch_info_struct[] =
 130 {
 131   N (bfd_mach_arm_2,      "armv2",   FALSE, & arch_info_struct[1]),
 132   N (bfd_mach_arm_2a,     "armv2a",  FALSE, & arch_info_struct[2]),
 133   N (bfd_mach_arm_3,      "armv3",   FALSE, & arch_info_struct[3]),
 134   N (bfd_mach_arm_3M,     "armv3m",  FALSE, & arch_info_struct[4]),
 135   N (bfd_mach_arm_4,      "armv4",   FALSE, & arch_info_struct[5]),
 136   N (bfd_mach_arm_4T,     "armv4t",  FALSE, & arch_info_struct[6]),
 137   N (bfd_mach_arm_5,      "armv5",   FALSE, & arch_info_struct[7]),
 138   N (bfd_mach_arm_5T,     "armv5t",  FALSE, & arch_info_struct[8]),
 139   N (bfd_mach_arm_5TE,    "armv5te", FALSE, & arch_info_struct[9]),
 140   N (bfd_mach_arm_XScale, "xscale",  FALSE, & arch_info_struct[10]),
 141   N (bfd_mach_arm_ep9312, "ep9312",  FALSE, & arch_info_struct[11]),
 142   N (bfd_mach_arm_iWMMXt, "iwmmxt",  FALSE, & arch_info_struct[12]),
 143   N (bfd_mach_arm_iWMMXt2, "iwmmxt2", FALSE, NULL)
 144 };
 145
 146 const bfd_arch_info_type bfd_arm_arch =
 147   N (0, "arm", TRUE, & arch_info_struct[0]);
 148
 149 /* Support functions used by both the COFF and ELF versions of the ARM port.  */
 150
 151 /* Handle the merging of the 'machine' settings of input file IBFD
 152    and an output file OBFD.  These values actually represent the
 153    different possible ARM architecture variants.
 154    Returns TRUE if they were merged successfully or FALSE otherwise.  */
 155
 156 bfd_boolean
 157 bfd_arm_merge_machines (bfd *ibfd, bfd *obfd)
 158 {
 159   unsigned int in  = bfd_get_mach (ibfd);
 160   unsigned int out = bfd_get_mach (obfd);
 161
 162   /* If the output architecture is unknown, we now have a value to set.  */
 163   if (out == bfd_mach_arm_unknown)
 164     bfd_set_arch_mach (obfd, bfd_arch_arm, in);
 165
 166   /* If the input architecture is unknown,
 167      then so must be the output architecture.  */
 168   else if (in == bfd_mach_arm_unknown)
 169     /* FIXME: We ought to have some way to
 170        override this on the command line.  */
 171     bfd_set_arch_mach (obfd, bfd_arch_arm, bfd_mach_arm_unknown);
 172
 173   /* If they are the same then nothing needs to be done.  */
 174   else if (out == in)
 175     ;
 176
 177   /* Otherwise the general principle that a earlier architecture can be
 178      linked with a later architecture to produce a binary that will execute
 179      on the later architecture.
 180
 181      We fail however if we attempt to link a Cirrus EP9312 binary with an
 182      Intel XScale binary, since these architecture have co-processors which
 183      will not both be present on the same physical hardware.  */
 184   else if (in == bfd_mach_arm_ep9312
 185            && (out == bfd_mach_arm_XScale
 186                || out == bfd_mach_arm_iWMMXt
 187                || out == bfd_mach_arm_iWMMXt2))
 188     {
 189       _bfd_error_handler (_("\
 190 error: %B is compiled for the EP9312, whereas %B is compiled for XScale"),
 191                           ibfd, obfd);
 192       bfd_set_error (bfd_error_wrong_format);
 193       return FALSE;
 194     }
 195   else if (out == bfd_mach_arm_ep9312
 196            && (in == bfd_mach_arm_XScale
 197                || in == bfd_mach_arm_iWMMXt
 198                || in == bfd_mach_arm_iWMMXt2))
 199     {
 200       _bfd_error_handler (_("\
 201 error: %B is compiled for the EP9312, whereas %B is compiled for XScale"),
 202                           obfd, ibfd);
 203       bfd_set_error (bfd_error_wrong_format);
 204       return FALSE;
 205     }
 206   else if (in > out)
 207     bfd_set_arch_mach (obfd, bfd_arch_arm, in);
 208   /* else
 209      Nothing to do.  */
 210
 211   return TRUE;
 212 }
 213
 214 typedef struct
 215 {
 216   unsigned char namesz[4];      /* Size of entry's owner string.  */
 217   unsigned char descsz[4];      /* Size of the note descriptor.  */
 218   unsigned char type[4];        /* Interpretation of the descriptor.  */
 219   char          name[1];        /* Start of the name+desc data.  */
 220 } arm_Note;
 221
 222 static bfd_boolean
 223 arm_check_note (bfd *abfd,
 224                 bfd_byte *buffer,
 225                 bfd_size_type buffer_size,
 226                 const char *expected_name,
 227                 char **description_return)
 228 {
 229   unsigned long namesz;
 230   unsigned long descsz;
 231   unsigned long type;
 232   char *        descr;
 233
 234   if (buffer_size < offsetof (arm_Note, name))
 235     return FALSE;
 236
 237   /* We have to extract the values this way to allow for a
 238      host whose endian-ness is different from the target.  */
 239   namesz = bfd_get_32 (abfd, buffer);
 240   descsz = bfd_get_32 (abfd, buffer + offsetof (arm_Note, descsz));
 241   type   = bfd_get_32 (abfd, buffer + offsetof (arm_Note, type));
 242   descr  = (char *) buffer + offsetof (arm_Note, name);
 243
 244   /* Check for buffer overflow.  */
 245   if (namesz + descsz + offsetof (arm_Note, name) > buffer_size)
 246     return FALSE;
 247
 248   if (expected_name == NULL)
 249     {
 250       if (namesz != 0)
 251         return FALSE;
 252     }
 253   else
 254     {
 255       if (namesz != ((strlen (expected_name) + 1 + 3) & ~3))
 256         return FALSE;
 257
 258       if (strcmp (descr, expected_name) != 0)
 259         return FALSE;
 260
 261       descr += (namesz + 3) & ~3;
 262     }
 263
 264   /* FIXME: We should probably check the type as well.  */
 265
 266   if (description_return != NULL)
 267     * description_return = descr;
 268
 269   return TRUE;
 270 }
 271
 272 #define NOTE_ARCH_STRING        "arch: "
 273
 274 bfd_boolean
 275 bfd_arm_update_notes (bfd *abfd, const char *note_section)
 276 {
 277   asection *     arm_arch_section;
 278   bfd_size_type  buffer_size;
 279   bfd_byte *     buffer;
 280   char *         arch_string;
 281   char *         expected;
 282
 283   /* Look for a note section.  If one is present check the architecture
 284      string encoded in it, and set it to the current architecture if it is
 285      different.  */
 286   arm_arch_section = bfd_get_section_by_name (abfd, note_section);
 287
 288   if (arm_arch_section == NULL)
 289     return TRUE;
 290
 291   buffer_size = arm_arch_section->size;
 292   if (buffer_size == 0)
 293     return FALSE;
 294
 295   if (!bfd_malloc_and_get_section (abfd, arm_arch_section, &buffer))
 296     goto FAIL;
 297
 298   /* Parse the note.  */
 299   if (! arm_check_note (abfd, buffer, buffer_size, NOTE_ARCH_STRING, & arch_string))
 300     goto FAIL;
 301
 302   /* Check the architecture in the note against the architecture of the bfd.  */
 303   switch (bfd_get_mach (abfd))
 304     {
 305     default:
 306     case bfd_mach_arm_unknown: expected = "unknown"; break;
 307     case bfd_mach_arm_2:       expected = "armv2"; break;
 308     case bfd_mach_arm_2a:      expected = "armv2a"; break;
 309     case bfd_mach_arm_3:       expected = "armv3"; break;
 310     case bfd_mach_arm_3M:      expected = "armv3M"; break;
 311     case bfd_mach_arm_4:       expected = "armv4"; break;
 312     case bfd_mach_arm_4T:      expected = "armv4t"; break;
 313     case bfd_mach_arm_5:       expected = "armv5"; break;
 314     case bfd_mach_arm_5T:      expected = "armv5t"; break;
 315     case bfd_mach_arm_5TE:     expected = "armv5te"; break;
 316     case bfd_mach_arm_XScale:  expected = "XScale"; break;
 317     case bfd_mach_arm_ep9312:  expected = "ep9312"; break;
 318     case bfd_mach_arm_iWMMXt:  expected = "iWMMXt"; break;
 319     case bfd_mach_arm_iWMMXt2: expected = "iWMMXt2"; break;
 320     }
 321
 322   if (strcmp (arch_string, expected) != 0)
 323     {
 324       strcpy ((char *) buffer + (offsetof (arm_Note, name)
 325                                  + ((strlen (NOTE_ARCH_STRING) + 3) & ~3)),
 326               expected);
 327
 328       if (! bfd_set_section_contents (abfd, arm_arch_section, buffer,
 329                                       (file_ptr) 0, buffer_size))
 330         {
 331           (*_bfd_error_handler)
 332             (_("warning: unable to update contents of %s section in %s"),
 333              note_section, bfd_get_filename (abfd));
 334           goto FAIL;
 335         }
 336     }
 337
 338   free (buffer);
 339   return TRUE;
 340
 341  FAIL:
 342   if (buffer != NULL)
 343     free (buffer);
 344   return FALSE;
 345 }
 346
 347
 348 static struct
 349 {
 350   const char * string;
 351   unsigned int mach;
 352 }
 353 architectures[] =
 354 {
 355   { "armv2",   bfd_mach_arm_2 },
 356   { "armv2a",  bfd_mach_arm_2a },
 357   { "armv3",   bfd_mach_arm_3 },
 358   { "armv3M",  bfd_mach_arm_3M },
 359   { "armv4",   bfd_mach_arm_4 },
 360   { "armv4t",  bfd_mach_arm_4T },
 361   { "armv5",   bfd_mach_arm_5 },
 362   { "armv5t",  bfd_mach_arm_5T },
 363   { "armv5te", bfd_mach_arm_5TE },
 364   { "XScale",  bfd_mach_arm_XScale },
 365   { "ep9312",  bfd_mach_arm_ep9312 },
 366   { "iWMMXt",  bfd_mach_arm_iWMMXt },
 367   { "iWMMXt2", bfd_mach_arm_iWMMXt2 }
 368 };
 369
 370 /* Extract the machine number stored in a note section.  */
 371 unsigned int
 372 bfd_arm_get_mach_from_notes (bfd *abfd, const char *note_section)
 373 {
 374   asection *     arm_arch_section;
 375   bfd_size_type  buffer_size;
 376   bfd_byte *     buffer;
 377   char *         arch_string;
 378   int            i;
 379
 380   /* Look for a note section.  If one is present check the architecture
 381      string encoded in it, and set it to the current architecture if it is
 382      different.  */
 383   arm_arch_section = bfd_get_section_by_name (abfd, note_section);
 384
 385   if (arm_arch_section == NULL)
 386     return bfd_mach_arm_unknown;
 387
 388   buffer_size = arm_arch_section->size;
 389   if (buffer_size == 0)
 390     return bfd_mach_arm_unknown;
 391
 392   if (!bfd_malloc_and_get_section (abfd, arm_arch_section, &buffer))
 393     goto FAIL;
 394
 395   /* Parse the note.  */
 396   if (! arm_check_note (abfd, buffer, buffer_size, NOTE_ARCH_STRING, & arch_string))
 397     goto FAIL;
 398
 399   /* Interpret the architecture string.  */
 400   for (i = ARRAY_SIZE (architectures); i--;)
 401     if (strcmp (arch_string, architectures[i].string) == 0)
 402       {
 403         free (buffer);
 404         return architectures[i].mach;
 405       }
 406
 407  FAIL:
 408   if (buffer != NULL)
 409     free (buffer);
 410   return bfd_mach_arm_unknown;
 411 }
 412
 413 bfd_boolean
 414 bfd_is_arm_special_symbol_name (const char * name, int type)
 415 {
 416   /* The ARM compiler outputs several obsolete forms.  Recognize them
 417      in addition to the standard $a, $t and $d.  We are somewhat loose
 418      in what we accept here, since the full set is not documented.  */
 419   if (!name || name[0] != '$')
 420     return FALSE;
 421   if (name[1] == 'a' || name[1] == 't' || name[1] == 'd')
 422     type &= BFD_ARM_SPECIAL_SYM_TYPE_MAP;
 423   else if (name[1] == 'm' || name[1] == 'f' || name[1] == 'p')
 424     type &= BFD_ARM_SPECIAL_SYM_TYPE_TAG;
 425   else if (name[1] >= 'a' && name[1] <= 'z')
 426     type &= BFD_ARM_SPECIAL_SYM_TYPE_OTHER;
 427   else
 428     return FALSE;
 429
 430   return (type != 0 && (name[2] == 0 || name[2] == '.'));
 431 }
 432