bfd/aout-cris.c

   1 /* BFD backend for CRIS a.out binaries.
   2    Copyright (C) 2000 Free Software Foundation, Inc.
   3    Contributed by Axis Communications AB.
   4    Written by Hans-Peter Nilsson.
   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 /* See info in the file PORTING for documentation of these macros and
  23    functions.  Beware; some of the information there is outdated.  */
  24
  25 #define N_HEADER_IN_TEXT(x) 0
  26 #define BYTES_IN_WORD 4
  27 #define N_TXTOFF(x) 32
  28 #define ENTRY_CAN_BE_ZERO
  29 #define TEXT_START_ADDR 0
  30
  31 /* If you change this to 4, you can not link to an address N*4+2.  */
  32 #define SEGMENT_SIZE 2
  33
  34 /* For some reason, if the a.out file has Z_MAGIC, then
  35    adata(abfd).exec_bytes_size is not used, but rather
  36    adata(abfd).zmagic_disk_block_size, even though the exec_header is
  37    *not* included in the text segment.  A simple workaround is to
  38    #define ZMAGIC_DISK_BLOCK_SIZE, which is used if defined; otherwise
  39    TARGET_PAGE_SIZE is used. */
  40 #define ZMAGIC_DISK_BLOCK_SIZE N_TXTOFF (0)
  41
  42 /* It seems odd at first to set a page-size this low, but gives greater
  43    freedom in where things can be linked.  The drawback is that you have
  44    to set alignment and padding in linker scripts.  */
  45 #define TARGET_PAGE_SIZE SEGMENT_SIZE
  46 #define TARGETNAME "a.out-cris"
  47
  48 /* N_SHARED_LIB gets this reasonable default as of 1999-07-12, but we
  49    have to work with 2.9.1.  Note that N_SHARED_LIB is used in a
  50    SUN-specific context, not applicable to CRIS.  */
  51 #define N_SHARED_LIB(x) 0
  52
  53 /* The definition here seems not used; just provided as a convention.  */
  54 #define DEFAULT_ARCH bfd_arch_cris
  55
  56 /* ??? Spacing might be essential for the parameters in this macro.
  57    Do Not Change.  */
  58 #define MY(OP) CAT (cris_aout_,OP)
  59 #define NAME(x,y) CAT3(cris_aout,_32_,y)
  60
  61 #include "bfd.h"
  62
  63 /* Version 1 of the header.  */
  64 #define MY_exec_hdr_flags 1
  65
  66 #define MY_write_object_contents MY(write_object_contents)
  67 static boolean MY(write_object_contents) PARAMS ((bfd *));
  68
  69 /* Forward this, so we can use a pointer to it in PARAMS.  */
  70 struct reloc_ext_external;
  71
  72 #define MY_swap_ext_reloc_out MY(swap_ext_reloc_out)
  73 static void MY(swap_ext_reloc_out) PARAMS ((bfd *, arelent *,
  74                                             struct reloc_ext_external *));
  75
  76 #define MY_swap_ext_reloc_in MY(swap_ext_reloc_in)
  77 static void MY(swap_ext_reloc_in) PARAMS ((bfd *, struct
  78                                            reloc_ext_external *,
  79                                            arelent *, asymbol **,
  80                                            bfd_size_type));
  81
  82 #define MY_set_sizes MY(set_sizes)
  83 static boolean MY(set_sizes) PARAMS ((bfd *));
  84
  85 /* To set back reloc_size to ext, we make MY(set_sizes) be called
  86    through this construct.  Note that MY_set_arch_mach is only called
  87    through SET_ARCH_MACH.  The default bfd_default_set_arch_mach will
  88    not call set_sizes.  */
  89
  90 #define MY_set_arch_mach NAME (aout, set_arch_mach)
  91 #define SET_ARCH_MACH(BFD, EXEC) \
  92  MY_set_arch_mach (BFD, DEFAULT_ARCH, N_MACHTYPE (EXEC))
  93
  94 /* These macros describe the binary layout of the reloc information we
  95    use in a file.  */
  96 #define RELOC_EXT_BITS_EXTERN_LITTLE 0x80
  97 #define RELOC_EXT_BITS_TYPE_LITTLE 3
  98 #define RELOC_EXT_BITS_TYPE_SH_LITTLE 0
  99
 100 #ifndef MY_get_section_contents
 101 #define MY_get_section_contents aout_32_get_section_contents
 102 #endif
 103
 104 /* Include generic functions (some are overridden above).  */
 105 #include "aout32.c"
 106 #include "aout-target.h"
 107
 108
 109 /* We need our own version to set header flags.  */
 110
 111 static boolean
 112 MY(write_object_contents) (abfd)
 113      bfd *abfd;
 114 {
 115   struct external_exec exec_bytes;
 116   struct internal_exec *execp = exec_hdr (abfd);
 117
 118   /* We set the reloc type to RELOC_EXT_SIZE, although setting it at all
 119      seems unnecessary when inspecting as and ld behavior (not an
 120      exhaustive inspection).  The default write_object_contents
 121      definition sets RELOC_EXT_SIZE, so we follow suite and set it too.  */
 122   obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 123
 124   /* Setting N_SET_MACHTYPE and using N_SET_FLAGS is not performed by
 125      the default definition.  */
 126   if (bfd_get_arch(abfd) == bfd_arch_cris)
 127     N_SET_MACHTYPE(*execp, M_CRIS);
 128
 129   N_SET_FLAGS (*execp, aout_backend_info (abfd)->exec_hdr_flags);
 130
 131   WRITE_HEADERS (abfd, execp);
 132
 133   return true;
 134 }
 135
 136
 137 /* We need our own for these reasons:
 138    - Assert that a normal 8, 16 or 32 reloc is output.
 139    - Fix what seems to be a weak-bug (perhaps there for valid reasons).  */
 140
 141 static void
 142 MY(swap_ext_reloc_out) (abfd, g, natptr)
 143      bfd *abfd;
 144      arelent *g;
 145      struct reloc_ext_external *natptr;
 146 {
 147   int r_index;
 148   int r_extern;
 149   unsigned int r_type;
 150   unsigned int r_addend;
 151   asymbol *sym = *(g->sym_ptr_ptr);
 152   asection *output_section = sym->section->output_section;
 153
 154   PUT_WORD (abfd, g->address, natptr->r_address);
 155
 156   r_type = (unsigned int) g->howto->type;
 157
 158   r_addend = g->addend;
 159   if ((sym->flags & BSF_SECTION_SYM) != 0)
 160     r_addend += (*(g->sym_ptr_ptr))->section->output_section->vma;
 161
 162   /* If this relocation is relative to a symbol then set the
 163      r_index to the symbols index, and the r_extern bit.
 164
 165      Absolute symbols can come in in two ways, either as an offset
 166      from the abs section, or as a symbol which has an abs value.
 167      check for that here.  */
 168
 169   if (bfd_is_abs_section (bfd_get_section (sym)))
 170     {
 171       r_extern = 0;
 172       r_index = N_ABS;
 173     }
 174   else if ((sym->flags & BSF_SECTION_SYM) == 0)
 175     {
 176       if (bfd_is_und_section (bfd_get_section (sym))
 177           /* Remember to check for weak symbols; they count as global.  */
 178           || (sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0)
 179         r_extern = 1;
 180       else
 181         r_extern = 0;
 182       r_index = (*(g->sym_ptr_ptr))->KEEPIT;
 183     }
 184   else
 185     {
 186       /* Just an ordinary section.  */
 187       r_extern = 0;
 188       r_index = output_section->target_index;
 189     }
 190
 191   /* The relocation type is the same as the canonical ones, but only
 192      the first 3 are used: RELOC_8, RELOC_16, RELOC_32.
 193      We may change this later, but assert this for the moment.  */
 194   if (r_type > 2)
 195     {
 196       (*_bfd_error_handler) (_("%s: Invalid relocation type exported: %d"),
 197                              bfd_get_filename (abfd), r_type);
 198
 199       bfd_set_error (bfd_error_wrong_format);
 200     }
 201
 202   /* Now the fun stuff.  */
 203   natptr->r_index[2] = r_index >> 16;
 204   natptr->r_index[1] = r_index >> 8;
 205   natptr->r_index[0] = r_index;
 206   natptr->r_type[0] =
 207      (r_extern ? RELOC_EXT_BITS_EXTERN_LITTLE : 0)
 208       | (r_type << RELOC_EXT_BITS_TYPE_SH_LITTLE);
 209
 210   PUT_WORD (abfd, r_addend, natptr->r_addend);
 211 }
 212
 213
 214 /* We need our own to assert that a normal 8, 16 or 32 reloc is input.  */
 215
 216 static void
 217 MY(swap_ext_reloc_in) (abfd, bytes, cache_ptr, symbols, symcount)
 218      bfd *abfd;
 219      struct reloc_ext_external *bytes;
 220      arelent *cache_ptr;
 221      asymbol **symbols;
 222      bfd_size_type symcount;
 223 {
 224   unsigned int r_index;
 225   int r_extern;
 226   unsigned int r_type;
 227   struct aoutdata *su = &(abfd->tdata.aout_data->a);
 228
 229   cache_ptr->address = (GET_SWORD (abfd, bytes->r_address));
 230
 231   /* Now the fun stuff.  */
 232   r_index =  (bytes->r_index[2] << 16)
 233     | (bytes->r_index[1] << 8)
 234     |  bytes->r_index[0];
 235   r_extern = (0 != (bytes->r_type[0] & RELOC_EXT_BITS_EXTERN_LITTLE));
 236   r_type = ((bytes->r_type[0]) >> RELOC_EXT_BITS_TYPE_SH_LITTLE)
 237     & RELOC_EXT_BITS_TYPE_LITTLE;
 238
 239   if (r_type > 2)
 240     {
 241       (*_bfd_error_handler) (_("%s: Invalid relocation type imported: %d"),
 242                              bfd_get_filename (abfd), r_type);
 243
 244       bfd_set_error(bfd_error_wrong_format);
 245     }
 246
 247   cache_ptr->howto =  howto_table_ext + r_type;
 248
 249   if (r_extern && r_index > symcount)
 250     {
 251       (*_bfd_error_handler)
 252         (_("%s: Bad relocation record imported: %d"),
 253          bfd_get_filename (abfd), r_index);
 254
 255       bfd_set_error (bfd_error_wrong_format);
 256
 257       /* We continue, so we can catch further errors.  */
 258       r_extern = 0;
 259       r_index = N_ABS;
 260     }
 261
 262   /* Magically uses r_extern, symbols etc.  Ugly, but it's what's in the
 263      default.  */
 264   MOVE_ADDRESS (GET_SWORD (abfd, bytes->r_addend));
 265 }
 266
 267
 268 /* We use the same as the default, except that we also set
 269    "obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;", to avoid changing
 270    NAME (aout, set_arch_mach) in aoutx.  */
 271
 272 static boolean
 273 MY(set_sizes) (abfd)
 274      bfd *abfd;
 275 {
 276   /* Just as the default in aout-target.h (with some #ifdefs folded)...  */
 277
 278   adata(abfd).page_size = TARGET_PAGE_SIZE;
 279   adata(abfd).segment_size = SEGMENT_SIZE;
 280   adata(abfd).zmagic_disk_block_size = ZMAGIC_DISK_BLOCK_SIZE;
 281   adata(abfd).exec_bytes_size = EXEC_BYTES_SIZE;
 282
 283   /* ... except for that we have the extended reloc.  The alternative
 284      would be to add a check on bfd_arch_cris in NAME (aout,
 285      set_arch_mach) in aoutx.h, but I don't want to do that since
 286      target-specific things should not be added there.  */
 287
 288   obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
 289
 290   return true;
 291 }
 292
 293 /*
 294  * Local variables:
 295  * eval: (c-set-style "gnu")
 296  * indent-tabs-mode: t
 297  * End:
 298  */