obj-ecoff.c revision 218822
1/* ECOFF object file format.
2   Copyright 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
3   2005  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 2, 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
36void
37ecoff_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
138void
139ecoff_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
182void
183obj_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
197static int
198ecoff_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
199{
200  return 1;
201}
202
203static void
204obj_ecoff_frob_symbol (symbolS *sym, int *puntp ATTRIBUTE_UNUSED)
205{
206  ecoff_frob_symbol (sym);
207}
208
209static void
210ecoff_pop_insert (void)
211{
212  pop_insert (obj_pseudo_table);
213}
214
215static int
216ecoff_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
240const 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
283const 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};
319