gas/config/obj-ecoff.c

   1 /* ECOFF object file format.
   2    Copyright (C) 1993-2024 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 #include "bfd/ecoff-bfd.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 precede .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 (sec, addr);
  95           addr += bfd_section_size (sec);
  96         }
  97     }
  98   for (i = 0; i < n_names; i++)
  99     if (secs[i])
 100       {
 101         bfd_set_section_vma (secs[i], addr);
 102         addr += bfd_section_size (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   gas_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   ecoff_data (stdoutput)->debug_info.alloc_syments = true;
 155   set = buf;
 156 #define SET(ptr, count, type, size) \
 157   if (hdr->count == 0) \
 158     ecoff_data (stdoutput)->debug_info.ptr = NULL; \
 159   else \
 160     { \
 161       ecoff_data (stdoutput)->debug_info.ptr = (type) set; \
 162       set += hdr->count * size; \
 163     }
 164
 165   SET (line, cbLine, unsigned char *, sizeof (unsigned char));
 166   SET (external_dnr, idnMax, void *, debug_swap->external_dnr_size);
 167   SET (external_pdr, ipdMax, void *, debug_swap->external_pdr_size);
 168   SET (external_sym, isymMax, void *, debug_swap->external_sym_size);
 169   SET (external_opt, ioptMax, void *, debug_swap->external_opt_size);
 170   SET (external_aux, iauxMax, union aux_ext *, sizeof (union aux_ext));
 171   SET (ss, issMax, char *, sizeof (char));
 172   SET (ssext, issExtMax, char *, sizeof (char));
 173   SET (external_rfd, crfd, void *, debug_swap->external_rfd_size);
 174   SET (external_fdr, ifdMax, void *, debug_swap->external_fdr_size);
 175   SET (external_ext, iextMax, void *, debug_swap->external_ext_size);
 176 #undef SET
 177 }
 178
 179 /* This is called by the ECOFF code to set the external information
 180    for a symbol.  We just pass it on to BFD, which expects the swapped
 181    information to be stored in the native field of the symbol.  */
 182
 183 void
 184 obj_ecoff_set_ext (symbolS *sym, EXTR *ext)
 185 {
 186   const struct ecoff_debug_swap * const debug_swap
 187     = &ecoff_backend (stdoutput)->debug_swap;
 188   ecoff_symbol_type *esym;
 189
 190   know (bfd_asymbol_flavour (symbol_get_bfdsym (sym))
 191         == bfd_target_ecoff_flavour);
 192   esym = ecoffsymbol (symbol_get_bfdsym (sym));
 193   esym->local = false;
 194   esym->native = xmalloc (debug_swap->external_ext_size);
 195   (*debug_swap->swap_ext_out) (stdoutput, ext, esym->native);
 196 }
 197
 198 static int
 199 ecoff_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
 200 {
 201   return 1;
 202 }
 203
 204 static void
 205 obj_ecoff_frob_symbol (symbolS *sym, int *puntp ATTRIBUTE_UNUSED)
 206 {
 207   ecoff_frob_symbol (sym);
 208 }
 209
 210 static void
 211 ecoff_pop_insert (void)
 212 {
 213   pop_insert (obj_pseudo_table);
 214 }
 215
 216 static int
 217 ecoff_separate_stab_sections (void)
 218 {
 219   return 0;
 220 }
 221
 222 /* These are the pseudo-ops we support in this file.  Only those
 223    relating to debugging information are supported here.
 224
 225    The following pseudo-ops from the Kane and Heinrich MIPS book
 226    should be defined here, but are currently unsupported: .bgnb,
 227    .endb, .verstamp, .vreg.
 228
 229    The following pseudo-ops from the Kane and Heinrich MIPS book are
 230    MIPS CPU specific, and should be defined by tc-mips.c: .alias,
 231    .extern, .galive, .gjaldef, .gjrlive, .livereg, .noalias, .option,
 232    .rdata, .sdata, .set.
 233
 234    The following pseudo-ops from the Kane and Heinrich MIPS book are
 235    not MIPS CPU specific, but are also not ECOFF specific.  I have
 236    only listed the ones which are not already in read.c.  It's not
 237    completely clear where these should be defined, but tc-mips.c is
 238    probably the most reasonable place: .asciiz, .asm0, .endr, .err,
 239    .half, .lab, .repeat, .struct, .weakext.  */
 240
 241 const pseudo_typeS obj_pseudo_table[] =
 242 {
 243   /* COFF style debugging information. .ln is not used; .loc is used
 244      instead.  */
 245   { "def",      ecoff_directive_def,    0 },
 246   { "dim",      ecoff_directive_dim,    0 },
 247   { "endef",    ecoff_directive_endef,  0 },
 248   { "file",     ecoff_directive_file,   0 },
 249   { "scl",      ecoff_directive_scl,    0 },
 250   { "size",     ecoff_directive_size,   0 },
 251   { "esize",    ecoff_directive_size,   0 },
 252   { "tag",      ecoff_directive_tag,    0 },
 253   { "type",     ecoff_directive_type,   0 },
 254   { "etype",    ecoff_directive_type,   0 },
 255   { "val",      ecoff_directive_val,    0 },
 256
 257   /* ECOFF specific debugging information.  */
 258   { "aent",     ecoff_directive_ent,    1 },
 259   { "begin",    ecoff_directive_begin,  0 },
 260   { "bend",     ecoff_directive_bend,   0 },
 261   { "end",      ecoff_directive_end,    0 },
 262   { "ent",      ecoff_directive_ent,    0 },
 263   { "fmask",    ecoff_directive_fmask,  0 },
 264   { "frame",    ecoff_directive_frame,  0 },
 265   { "loc",      ecoff_directive_loc,    0 },
 266   { "mask",     ecoff_directive_mask,   0 },
 267
 268   /* Other ECOFF directives.  */
 269   { "extern",   ecoff_directive_extern, 0 },
 270
 271 #ifndef TC_MIPS
 272   /* For TC_MIPS, tc-mips.c adds this.  */
 273   { "weakext",  ecoff_directive_weakext, 0 },
 274 #endif
 275
 276   /* These are used on Irix.  I don't know how to implement them.  */
 277   { "bgnb",     s_ignore,               0 },
 278   { "endb",     s_ignore,               0 },
 279   { "verstamp", s_ignore,               0 },
 280
 281   /* Sentinel.  */
 282   { NULL,       s_ignore,               0 }
 283 };
 284
 285 const struct format_ops ecoff_format_ops =
 286 {
 287   bfd_target_ecoff_flavour,
 288   0,    /* dfl_leading_underscore.  */
 289
 290   /* FIXME: A comment why emit_section_symbols is different here (1) from
 291      the single-format definition (0) would be in order.  */
 292   1,    /* emit_section_symbols.  */
 293   0,    /* begin.  */
 294   0,    /* end.  */
 295   ecoff_new_file,
 296   obj_ecoff_frob_symbol,
 297   ecoff_frob_file,
 298   0,    /* frob_file_before_adjust.  */
 299   ecoff_frob_file_before_fix,
 300   0,    /* frob_file_after_relocs.  */
 301   0,    /* s_get_size.  */
 302   0,    /* s_set_size.  */
 303   0,    /* s_get_align.  */
 304   0,    /* s_set_align.  */
 305   0,    /* s_get_other.  */
 306   0,    /* s_set_other.  */
 307   0,    /* s_get_desc.  */
 308   0,    /* s_set_desc.  */
 309   0,    /* s_get_type.  */
 310   0,    /* s_set_type.  */
 311   0,    /* copy_symbol_attributes.  */
 312   ecoff_generate_asm_lineno,
 313   ecoff_stab,
 314   ecoff_separate_stab_sections,
 315   0,    /* init_stab_section.  */
 316   ecoff_sec_sym_ok_for_reloc,
 317   ecoff_pop_insert,
 318   ecoff_set_ext,
 319   ecoff_read_begin_hook,
 320   ecoff_symbol_new_hook,
 321   ecoff_symbol_clone_hook,
 322   0     /* adjust_symtab.  */
 323 };