gas/config/obj-ecoff.c

   1 /* ECOFF object file format.
   2    Copyright 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
   3    2005, 2007  Free Software Foundation, Inc.
   4    Contributed by Cygnus Support.
   5    This file was put together by Ian Lance Taylor <ian@cygnus.com>.
   6
   7    This file is part of GAS.
   8
   9    GAS is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3, or (at your option)
  12    any later version.
  13
  14    GAS is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with GAS; see the file COPYING.  If not, write to the Free
  21    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  22    02110-1301, USA.  */
  23
  24 #define OBJ_HEADER "obj-ecoff.h"
  25 #include "as.h"
  26 #include "coff/internal.h"
  27 #include "bfd/libcoff.h"
  28 #include "bfd/libecoff.h"
  29
  30 /* Almost all of the ECOFF support is actually in ecoff.c in the main
  31    gas directory.  This file mostly just arranges to call that one at
  32    the right times.  */
  33
  34 /* Set section VMAs and GP values before reloc processing.  */
  35
  36 void
  37 ecoff_frob_file_before_fix (void)
  38 {
  39   bfd_vma addr;
  40   asection *sec;
  41
  42   /* Set the section VMA values.  We force the .sdata and .sbss
  43      sections to the end to ensure that their VMA addresses are close
  44      together so that the GP register can address both of them.  We
  45      put the .bss section after the .sbss section.
  46
  47      Also, for the Alpha, we must sort the sections, to make sure they
  48      appear in the output file in the correct order.  (Actually, maybe
  49      this is a job for BFD.  But the VMAs computed would be out of
  50      whack if we computed them given our initial, random ordering.
  51      It's possible that that wouldn't break things; I could do some
  52      experimenting sometime and find out.
  53
  54      This output ordering of sections is magic, on the Alpha, at
  55      least.  The .lita section must come before .lit8 and .lit4,
  56      otherwise the OSF/1 linker may silently trash the .lit{4,8}
  57      section contents.  Also, .text must preceed .rdata.  These differ
  58      from the order described in some parts of the DEC OSF/1 Assembly
  59      Language Programmer's Guide, but that order doesn't seem to work
  60      with their linker.
  61
  62      I don't know if section ordering on the MIPS is important.  */
  63
  64   static const char *const names[] =
  65   {
  66     /* text segment */
  67     ".text", ".rdata", ".init", ".fini",
  68     /* data segment */
  69     ".data", ".lita", ".lit8", ".lit4", ".sdata", ".got",
  70     /* bss segment */
  71     ".sbss", ".bss",
  72   };
  73 #define n_names ((int) (sizeof (names) / sizeof (names[0])))
  74
  75   /* Sections that match names, order to be straightened out later.  */
  76   asection *secs[n_names];
  77   int i;
  78
  79   addr = 0;
  80   for (i = 0; i < n_names; i++)
  81     secs[i] = NULL;
  82
  83   for (sec = stdoutput->sections; sec != NULL; sec = sec->next)
  84     {
  85       for (i = 0; i < n_names; i++)
  86         if (!strcmp (sec->name, names[i]))
  87           {
  88             secs[i] = sec;
  89             bfd_section_list_remove (stdoutput, sec);
  90             break;
  91           }
  92       if (i == n_names)
  93         {
  94           bfd_set_section_vma (stdoutput, sec, addr);
  95           addr += bfd_section_size (stdoutput, sec);
  96         }
  97     }
  98   for (i = 0; i < n_names; i++)
  99     if (secs[i])
 100       {
 101         bfd_set_section_vma (stdoutput, secs[i], addr);
 102         addr += bfd_section_size (stdoutput, secs[i]);
 103       }
 104   for (i = n_names - 1; i >= 0; i--)
 105     if (secs[i])
 106       bfd_section_list_prepend (stdoutput, secs[i]);
 107
 108   /* Fill in the register masks.  */
 109   {
 110     unsigned long gprmask = 0;
 111     unsigned long fprmask = 0;
 112     unsigned long *cprmask = NULL;
 113
 114 #ifdef TC_MIPS
 115     /* Fill in the MIPS register masks.  It's probably not worth
 116        setting up a generic interface for this.  */
 117     gprmask = mips_gprmask;
 118     cprmask = mips_cprmask;
 119 #endif
 120
 121 #ifdef TC_ALPHA
 122     alpha_frob_ecoff_data ();
 123
 124     if (! bfd_ecoff_set_gp_value (stdoutput, alpha_gp_value))
 125       as_fatal (_("Can't set GP value"));
 126
 127     gprmask = alpha_gprmask;
 128     fprmask = alpha_fprmask;
 129 #endif
 130
 131     if (! bfd_ecoff_set_regmasks (stdoutput, gprmask, fprmask, cprmask))
 132       as_fatal (_("Can't set register masks"));
 133   }
 134 }
 135
 136 /* Swap out the symbols and debugging information for BFD.  */
 137
 138 void
 139 ecoff_frob_file (void)
 140 {
 141   const struct ecoff_debug_swap * const debug_swap
 142     = &ecoff_backend (stdoutput)->debug_swap;
 143   bfd_vma addr ATTRIBUTE_UNUSED;
 144   HDRR *hdr;
 145   char *buf;
 146   char *set;
 147
 148   /* Build the ECOFF debugging information.  */
 149   assert (ecoff_data (stdoutput) != 0);
 150   hdr = &ecoff_data (stdoutput)->debug_info.symbolic_header;
 151   ecoff_build_debug (hdr, &buf, debug_swap);
 152
 153   /* Finish up the ecoff_tdata structure.  */
 154   set = buf;
 155 #define SET(ptr, count, type, size) \
 156   if (hdr->count == 0) \
 157     ecoff_data (stdoutput)->debug_info.ptr = NULL; \
 158   else \
 159     { \
 160       ecoff_data (stdoutput)->debug_info.ptr = (type) set; \
 161       set += hdr->count * size; \
 162     }
 163
 164   SET (line, cbLine, unsigned char *, sizeof (unsigned char));
 165   SET (external_dnr, idnMax, void *, debug_swap->external_dnr_size);
 166   SET (external_pdr, ipdMax, void *, debug_swap->external_pdr_size);
 167   SET (external_sym, isymMax, void *, debug_swap->external_sym_size);
 168   SET (external_opt, ioptMax, void *, debug_swap->external_opt_size);
 169   SET (external_aux, iauxMax, union aux_ext *, sizeof (union aux_ext));
 170   SET (ss, issMax, char *, sizeof (char));
 171   SET (ssext, issExtMax, char *, sizeof (char));
 172   SET (external_rfd, crfd, void *, debug_swap->external_rfd_size);
 173   SET (external_fdr, ifdMax, void *, debug_swap->external_fdr_size);
 174   SET (external_ext, iextMax, void *, debug_swap->external_ext_size);
 175 #undef SET
 176 }
 177
 178 /* This is called by the ECOFF code to set the external information
 179    for a symbol.  We just pass it on to BFD, which expects the swapped
 180    information to be stored in the native field of the symbol.  */
 181
 182 void
 183 obj_ecoff_set_ext (symbolS *sym, EXTR *ext)
 184 {
 185   const struct ecoff_debug_swap * const debug_swap
 186     = &ecoff_backend (stdoutput)->debug_swap;
 187   ecoff_symbol_type *esym;
 188
 189   know (bfd_asymbol_flavour (symbol_get_bfdsym (sym))
 190         == bfd_target_ecoff_flavour);
 191   esym = ecoffsymbol (symbol_get_bfdsym (sym));
 192   esym->local = FALSE;
 193   esym->native = xmalloc (debug_swap->external_ext_size);
 194   (*debug_swap->swap_ext_out) (stdoutput, ext, esym->native);
 195 }
 196
 197 static int
 198 ecoff_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
 199 {
 200   return 1;
 201 }
 202
 203 static void
 204 obj_ecoff_frob_symbol (symbolS *sym, int *puntp ATTRIBUTE_UNUSED)
 205 {
 206   ecoff_frob_symbol (sym);
 207 }
 208
 209 static void
 210 ecoff_pop_insert (void)
 211 {
 212   pop_insert (obj_pseudo_table);
 213 }
 214
 215 static int
 216 ecoff_separate_stab_sections (void)
 217 {
 218   return 0;
 219 }
 220
 221 /* These are the pseudo-ops we support in this file.  Only those
 222    relating to debugging information are supported here.
 223
 224    The following pseudo-ops from the Kane and Heinrich MIPS book
 225    should be defined here, but are currently unsupported: .aent,
 226    .bgnb, .endb, .verstamp, .vreg.
 227
 228    The following pseudo-ops from the Kane and Heinrich MIPS book are
 229    MIPS CPU specific, and should be defined by tc-mips.c: .alias,
 230    .extern, .galive, .gjaldef, .gjrlive, .livereg, .noalias, .option,
 231    .rdata, .sdata, .set.
 232
 233    The following pseudo-ops from the Kane and Heinrich MIPS book are
 234    not MIPS CPU specific, but are also not ECOFF specific.  I have
 235    only listed the ones which are not already in read.c.  It's not
 236    completely clear where these should be defined, but tc-mips.c is
 237    probably the most reasonable place: .asciiz, .asm0, .endr, .err,
 238    .half, .lab, .repeat, .struct, .weakext.  */
 239
 240 const pseudo_typeS obj_pseudo_table[] =
 241 {
 242   /* COFF style debugging information. .ln is not used; .loc is used
 243      instead.  */
 244   { "def",      ecoff_directive_def,    0 },
 245   { "dim",      ecoff_directive_dim,    0 },
 246   { "endef",    ecoff_directive_endef,  0 },
 247   { "file",     ecoff_directive_file,   0 },
 248   { "scl",      ecoff_directive_scl,    0 },
 249   { "size",     ecoff_directive_size,   0 },
 250   { "esize",    ecoff_directive_size,   0 },
 251   { "tag",      ecoff_directive_tag,    0 },
 252   { "type",     ecoff_directive_type,   0 },
 253   { "etype",    ecoff_directive_type,   0 },
 254   { "val",      ecoff_directive_val,    0 },
 255
 256   /* ECOFF specific debugging information.  */
 257   { "begin",    ecoff_directive_begin,  0 },
 258   { "bend",     ecoff_directive_bend,   0 },
 259   { "end",      ecoff_directive_end,    0 },
 260   { "ent",      ecoff_directive_ent,    0 },
 261   { "fmask",    ecoff_directive_fmask,  0 },
 262   { "frame",    ecoff_directive_frame,  0 },
 263   { "loc",      ecoff_directive_loc,    0 },
 264   { "mask",     ecoff_directive_mask,   0 },
 265
 266   /* Other ECOFF directives.  */
 267   { "extern",   ecoff_directive_extern, 0 },
 268
 269 #ifndef TC_MIPS
 270   /* For TC_MIPS, tc-mips.c adds this.  */
 271   { "weakext",  ecoff_directive_weakext, 0 },
 272 #endif
 273
 274   /* These are used on Irix.  I don't know how to implement them.  */
 275   { "bgnb",     s_ignore,               0 },
 276   { "endb",     s_ignore,               0 },
 277   { "verstamp", s_ignore,               0 },
 278
 279   /* Sentinel.  */
 280   { NULL,       s_ignore,               0 }
 281 };
 282
 283 const struct format_ops ecoff_format_ops =
 284 {
 285   bfd_target_ecoff_flavour,
 286   0,    /* dfl_leading_underscore.  */
 287
 288   /* FIXME: A comment why emit_section_symbols is different here (1) from
 289      the single-format definition (0) would be in order.  */
 290   1,    /* emit_section_symbols.  */
 291   0,    /* begin.  */
 292   ecoff_new_file,
 293   obj_ecoff_frob_symbol,
 294   ecoff_frob_file,
 295   0,    /* frob_file_before_adjust.  */
 296   ecoff_frob_file_before_fix,
 297   0,    /* frob_file_after_relocs.  */
 298   0,    /* s_get_size.  */
 299   0,    /* s_set_size.  */
 300   0,    /* s_get_align.  */
 301   0,    /* s_set_align.  */
 302   0,    /* s_get_other.  */
 303   0,    /* s_set_other.  */
 304   0,    /* s_get_desc.  */
 305   0,    /* s_set_desc.  */
 306   0,    /* s_get_type.  */
 307   0,    /* s_set_type.  */
 308   0,    /* copy_symbol_attributes.  */
 309   ecoff_generate_asm_lineno,
 310   ecoff_stab,
 311   ecoff_separate_stab_sections,
 312   0,    /* init_stab_section.  */
 313   ecoff_sec_sym_ok_for_reloc,
 314   ecoff_pop_insert,
 315   ecoff_set_ext,
 316   ecoff_read_begin_hook,
 317   ecoff_symbol_new_hook
 318 };