gas/config/obj-ecoff.c

   1 /* ECOFF object file format.
   2    Copyright (C) 1993-2019 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support.
   4    This file was put together by Ian Lance Taylor <ian@cygnus.com>.
   5
   6    This file is part of GAS.
   7
   8    GAS 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, or (at your option)
  11    any later version.
  12
  13    GAS 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 GAS; see the file COPYING.  If not, write to the Free
  20    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  21    02110-1301, USA.  */
  22
  23 #define OBJ_HEADER "obj-ecoff.h"
  24 #include "as.h"
  25 #include "coff/internal.h"
  26 #include "bfd/libcoff.h"
  27 #include "bfd/libecoff.h"
  28
  29 /* Almost all of the ECOFF support is actually in ecoff.c in the main
  30    gas directory.  This file mostly just arranges to call that one at
  31    the right times.  */
  32
  33 /* Set section VMAs and GP values before reloc processing.  */
  34
  35 void
  36 ecoff_frob_file_before_fix (void)
  37 {
  38   bfd_vma addr;
  39   asection *sec;
  40
  41   /* Set the section VMA values.  We force the .sdata and .sbss
  42      sections to the end to ensure that their VMA addresses are close
  43      together so that the GP register can address both of them.  We
  44      put the .bss section after the .sbss section.
  45
  46      Also, for the Alpha, we must sort the sections, to make sure they
  47      appear in the output file in the correct order.  (Actually, maybe
  48      this is a job for BFD.  But the VMAs computed would be out of
  49      whack if we computed them given our initial, random ordering.
  50      It's possible that that wouldn't break things; I could do some
  51      experimenting sometime and find out.
  52
  53      This output ordering of sections is magic, on the Alpha, at
  54      least.  The .lita section must come before .lit8 and .lit4,
  55      otherwise the OSF/1 linker may silently trash the .lit{4,8}
  56      section contents.  Also, .text must precede .rdata.  These differ
  57      from the order described in some parts of the DEC OSF/1 Assembly
  58      Language Programmer's Guide, but that order doesn't seem to work
  59      with their linker.
  60
  61      I don't know if section ordering on the MIPS is important.  */
  62
  63   static const char *const names[] =
  64   {
  65     /* text segment */
  66     ".text", ".rdata", ".init", ".fini",
  67     /* data segment */
  68     ".data", ".lita", ".lit8", ".lit4", ".sdata", ".got",
  69     /* bss segment */
  70     ".sbss", ".bss",
  71   };
  72 #define n_names ((int) (sizeof (names) / sizeof (names[0])))
  73
  74   /* Sections that match names, order to be straightened out later.  */
  75   asection *secs[n_names];
  76   int i;
  77
  78   addr = 0;
  79   for (i = 0; i < n_names; i++)
  80     secs[i] = NULL;
  81
  82   for (sec = stdoutput->sections; sec != NULL; sec = sec->next)
  83     {
  84       for (i = 0; i < n_names; i++)
  85         if (!strcmp (sec->name, names[i]))
  86           {
  87             secs[i] = sec;
  88             bfd_section_list_remove (stdoutput, sec);
  89             break;
  90           }
  91       if (i == n_names)
  92         {
  93           bfd_set_section_vma (stdoutput, sec, addr);
  94           addr += bfd_section_size (stdoutput, sec);
  95         }
  96     }
  97   for (i = 0; i < n_names; i++)
  98     if (secs[i])
  99       {
 100         bfd_set_section_vma (stdoutput, secs[i], addr);
 101         addr += bfd_section_size (stdoutput, secs[i]);
 102       }
 103   for (i = n_names - 1; i >= 0; i--)
 104     if (secs[i])
 105       bfd_section_list_prepend (stdoutput, secs[i]);
 106
 107   /* Fill in the register masks.  */
 108   {
 109     unsigned long gprmask = 0;
 110     unsigned long fprmask = 0;
 111     unsigned long *cprmask = NULL;
 112
 113 #ifdef TC_MIPS
 114     /* Fill in the MIPS register masks.  It's probably not worth
 115        setting up a generic interface for this.  */
 116     gprmask = mips_gprmask;
 117     cprmask = mips_cprmask;
 118 #endif
 119
 120 #ifdef TC_ALPHA
 121     alpha_frob_ecoff_data ();
 122
 123     if (! bfd_ecoff_set_gp_value (stdoutput, alpha_gp_value))
 124       as_fatal (_("Can't set GP value"));
 125
 126     gprmask = alpha_gprmask;
 127     fprmask = alpha_fprmask;
 128 #endif
 129
 130     if (! bfd_ecoff_set_regmasks (stdoutput, gprmask, fprmask, cprmask))
 131       as_fatal (_("Can't set register masks"));
 132   }
 133 }
 134
 135 /* Swap out the symbols and debugging information for BFD.  */
 136
 137 void
 138 ecoff_frob_file (void)
 139 {
 140   const struct ecoff_debug_swap * const debug_swap
 141     = &ecoff_backend (stdoutput)->debug_swap;
 142   bfd_vma addr ATTRIBUTE_UNUSED;
 143   HDRR *hdr;
 144   char *buf;
 145   char *set;
 146
 147   /* Build the ECOFF debugging information.  */
 148   gas_assert (ecoff_data (stdoutput) != 0);
 149   hdr = &ecoff_data (stdoutput)->debug_info.symbolic_header;
 150   ecoff_build_debug (hdr, &buf, debug_swap);
 151
 152   /* Finish up the ecoff_tdata structure.  */
 153   set = buf;
 154 #define SET(ptr, count, type, size) \
 155   if (hdr->count == 0) \
 156     ecoff_data (stdoutput)->debug_info.ptr = NULL; \
 157   else \
 158     { \
 159       ecoff_data (stdoutput)->debug_info.ptr = (type) set; \
 160       set += hdr->count * size; \
 161     }
 162
 163   SET (line, cbLine, unsigned char *, sizeof (unsigned char));
 164   SET (external_dnr, idnMax, void *, debug_swap->external_dnr_size);
 165   SET (external_pdr, ipdMax, void *, debug_swap->external_pdr_size);
 166   SET (external_sym, isymMax, void *, debug_swap->external_sym_size);
 167   SET (external_opt, ioptMax, void *, debug_swap->external_opt_size);
 168   SET (external_aux, iauxMax, union aux_ext *, sizeof (union aux_ext));
 169   SET (ss, issMax, char *, sizeof (char));
 170   SET (ssext, issExtMax, char *, sizeof (char));
 171   SET (external_rfd, crfd, void *, debug_swap->external_rfd_size);
 172   SET (external_fdr, ifdMax, void *, debug_swap->external_fdr_size);
 173   SET (external_ext, iextMax, void *, debug_swap->external_ext_size);
 174 #undef SET
 175 }
 176
 177 /* This is called by the ECOFF code to set the external information
 178    for a symbol.  We just pass it on to BFD, which expects the swapped
 179    information to be stored in the native field of the symbol.  */
 180
 181 void
 182 obj_ecoff_set_ext (symbolS *sym, EXTR *ext)
 183 {
 184   const struct ecoff_debug_swap * const debug_swap
 185     = &ecoff_backend (stdoutput)->debug_swap;
 186   ecoff_symbol_type *esym;
 187
 188   know (bfd_asymbol_flavour (symbol_get_bfdsym (sym))
 189         == bfd_target_ecoff_flavour);
 190   esym = ecoffsymbol (symbol_get_bfdsym (sym));
 191   esym->local = FALSE;
 192   esym->native = xmalloc (debug_swap->external_ext_size);
 193   (*debug_swap->swap_ext_out) (stdoutput, ext, esym->native);
 194 }
 195
 196 static int
 197 ecoff_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
 198 {
 199   return 1;
 200 }
 201
 202 static void
 203 obj_ecoff_frob_symbol (symbolS *sym, int *puntp ATTRIBUTE_UNUSED)
 204 {
 205   ecoff_frob_symbol (sym);
 206 }
 207
 208 static void
 209 ecoff_pop_insert (void)
 210 {
 211   pop_insert (obj_pseudo_table);
 212 }
 213
 214 static int
 215 ecoff_separate_stab_sections (void)
 216 {
 217   return 0;
 218 }
 219
 220 /* These are the pseudo-ops we support in this file.  Only those
 221    relating to debugging information are supported here.
 222
 223    The following pseudo-ops from the Kane and Heinrich MIPS book
 224    should be defined here, but are currently unsupported: .bgnb,
 225    .endb, .verstamp, .vreg.
 226
 227    The following pseudo-ops from the Kane and Heinrich MIPS book are
 228    MIPS CPU specific, and should be defined by tc-mips.c: .alias,
 229    .extern, .galive, .gjaldef, .gjrlive, .livereg, .noalias, .option,
 230    .rdata, .sdata, .set.
 231
 232    The following pseudo-ops from the Kane and Heinrich MIPS book are
 233    not MIPS CPU specific, but are also not ECOFF specific.  I have
 234    only listed the ones which are not already in read.c.  It's not
 235    completely clear where these should be defined, but tc-mips.c is
 236    probably the most reasonable place: .asciiz, .asm0, .endr, .err,
 237    .half, .lab, .repeat, .struct, .weakext.  */
 238
 239 const pseudo_typeS obj_pseudo_table[] =
 240 {
 241   /* COFF style debugging information. .ln is not used; .loc is used
 242      instead.  */
 243   { "def",      ecoff_directive_def,    0 },
 244   { "dim",      ecoff_directive_dim,    0 },
 245   { "endef",    ecoff_directive_endef,  0 },
 246   { "file",     ecoff_directive_file,   0 },
 247   { "scl",      ecoff_directive_scl,    0 },
 248   { "size",     ecoff_directive_size,   0 },
 249   { "esize",    ecoff_directive_size,   0 },
 250   { "tag",      ecoff_directive_tag,    0 },
 251   { "type",     ecoff_directive_type,   0 },
 252   { "etype",    ecoff_directive_type,   0 },
 253   { "val",      ecoff_directive_val,    0 },
 254
 255   /* ECOFF specific debugging information.  */
 256   { "aent",     ecoff_directive_ent,    1 },
 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   ecoff_symbol_clone_hook,
 319   0     /* adjust_symtab.  */
 320 };