1/* BFD backend for MIPS BSD (a.out) binaries.
2   Copyright 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003
3   Free Software Foundation, Inc.
4   Written by Ralph Campbell.
5
6This file is part of BFD, the Binary File Descriptor library.
7
8This program is free software; you can redistribute it and/or modify
9it under the terms of the GNU General Public License as published by
10the Free Software Foundation; either version 2 of the License, or
11(at your option) any later version.
12
13This program is distributed in the hope that it will be useful,
14but WITHOUT ANY WARRANTY; without even the implied warranty of
15MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16GNU General Public License for more details.
17
18You should have received a copy of the GNU General Public License
19along with this program; if not, write to the Free Software
20Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
21
22/* #define ENTRY_CAN_BE_ZERO */
23#define N_HEADER_IN_TEXT(x) 1
24#define N_SHARED_LIB(x) 0
25#define N_TXTADDR(x) \
26    (N_MAGIC(x) != ZMAGIC ? (x).a_entry :	/* object file or NMAGIC */\
27	    TEXT_START_ADDR + EXEC_BYTES_SIZE	/* no padding */\
28    )
29#define N_DATADDR(x) (N_TXTADDR(x)+N_TXTSIZE(x))
30#define TEXT_START_ADDR 4096
31#define TARGET_PAGE_SIZE 4096
32#define SEGMENT_SIZE TARGET_PAGE_SIZE
33#define DEFAULT_ARCH bfd_arch_mips
34#define MACHTYPE_OK(mtype) ((mtype) == M_UNKNOWN \
35			    || (mtype) == M_MIPS1 || (mtype) == M_MIPS2)
36#define MY_symbol_leading_char '\0'
37
38/* Do not "beautify" the CONCAT* macro args.  Traditional C will not
39   remove whitespace added here, and thus will fail to concatenate
40   the tokens.  */
41#define MY(OP) CONCAT2 (mipsbsd_,OP)
42
43#include "bfd.h"
44#include "sysdep.h"
45#include "libbfd.h"
46#include "libaout.h"
47
48#define SET_ARCH_MACH(ABFD, EXEC) \
49  MY(set_arch_mach) (ABFD, N_MACHTYPE (EXEC)); \
50  MY(choose_reloc_size) (ABFD);
51static void MY(set_arch_mach) PARAMS ((bfd *abfd, unsigned long machtype));
52static void MY(choose_reloc_size) PARAMS ((bfd *abfd));
53
54#define MY_write_object_contents MY(write_object_contents)
55static bfd_boolean MY(write_object_contents) PARAMS ((bfd *abfd));
56
57/* We can't use MY(x) here because it leads to a recursive call to CONCAT2
58   when expanded inside JUMP_TABLE.  */
59#define MY_bfd_reloc_type_lookup mipsbsd_reloc_howto_type_lookup
60#define MY_canonicalize_reloc mipsbsd_canonicalize_reloc
61
62#define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
63#define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols
64#define MY_final_link_callback unused
65#define MY_bfd_final_link _bfd_generic_final_link
66
67#define MY_backend_data &MY(backend_data)
68#define MY_BFD_TARGET
69
70#include "aout-target.h"
71
72static bfd_reloc_status_type mips_fix_jmp_addr
73  PARAMS ((bfd *, arelent *, struct bfd_symbol *, PTR, asection *,
74	   bfd *, char **));
75static reloc_howto_type *MY(reloc_howto_type_lookup)
76  PARAMS ((bfd *, bfd_reloc_code_real_type));
77
78long MY(canonicalize_reloc) PARAMS ((bfd *, sec_ptr, arelent **, asymbol **));
79
80static void
81MY(set_arch_mach) (abfd, machtype)
82     bfd *abfd;
83     unsigned long machtype;
84{
85  enum bfd_architecture arch;
86  unsigned int machine;
87
88  /* Determine the architecture and machine type of the object file.  */
89  switch (machtype)
90    {
91    case M_MIPS1:
92      arch = bfd_arch_mips;
93      machine = bfd_mach_mips3000;
94      break;
95
96    case M_MIPS2:
97      arch = bfd_arch_mips;
98      machine = bfd_mach_mips4000;
99      break;
100
101    default:
102      arch = bfd_arch_obscure;
103      machine = 0;
104      break;
105    }
106
107  bfd_set_arch_mach (abfd, arch, machine);
108}
109
110/* Determine the size of a relocation entry, based on the architecture */
111static void
112MY (choose_reloc_size) (abfd)
113     bfd *abfd;
114{
115  switch (bfd_get_arch (abfd))
116    {
117    case bfd_arch_sparc:
118    case bfd_arch_mips:
119      obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;
120      break;
121    default:
122      obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;
123      break;
124    }
125}
126
127/* Write an object file in BSD a.out format.
128  Section contents have already been written.  We write the
129  file header, symbols, and relocation.  */
130
131static bfd_boolean
132MY (write_object_contents) (abfd)
133     bfd *abfd;
134{
135  struct external_exec exec_bytes;
136  struct internal_exec *execp = exec_hdr (abfd);
137
138  /* Magic number, maestro, please!  */
139  switch (bfd_get_arch (abfd))
140    {
141    case bfd_arch_m68k:
142      switch (bfd_get_mach (abfd))
143	{
144	case bfd_mach_m68010:
145	  N_SET_MACHTYPE (*execp, M_68010);
146	  break;
147	default:
148	case bfd_mach_m68020:
149	  N_SET_MACHTYPE (*execp, M_68020);
150	  break;
151	}
152      break;
153    case bfd_arch_sparc:
154      N_SET_MACHTYPE (*execp, M_SPARC);
155      break;
156    case bfd_arch_i386:
157      N_SET_MACHTYPE (*execp, M_386);
158      break;
159    case bfd_arch_mips:
160      switch (bfd_get_mach (abfd))
161	{
162	case bfd_mach_mips4000:
163	case bfd_mach_mips6000:
164	  N_SET_MACHTYPE (*execp, M_MIPS2);
165	  break;
166	default:
167	  N_SET_MACHTYPE (*execp, M_MIPS1);
168	  break;
169	}
170      break;
171    default:
172      N_SET_MACHTYPE (*execp, M_UNKNOWN);
173    }
174
175  MY (choose_reloc_size) (abfd);
176
177  WRITE_HEADERS (abfd, execp);
178
179  return TRUE;
180}
181
182/* MIPS relocation types.  */
183#define MIPS_RELOC_32		0
184#define MIPS_RELOC_JMP		1
185#define MIPS_RELOC_WDISP16	2
186#define MIPS_RELOC_HI16		3
187#define MIPS_RELOC_HI16_S	4
188#define MIPS_RELOC_LO16		5
189
190/* This is only called when performing a BFD_RELOC_MIPS_JMP relocation.
191   The jump destination address is formed from the upper 4 bits of the
192   "current" program counter concatenated with the jump instruction's
193   26 bit field and two trailing zeros.
194   If the destination address is not in the same segment as the "current"
195   program counter, then we need to signal an error.  */
196
197static bfd_reloc_status_type
198mips_fix_jmp_addr (abfd, reloc_entry, symbol, data, input_section, output_bfd,
199		   error_message)
200     bfd *abfd ATTRIBUTE_UNUSED;
201     arelent *reloc_entry;
202     struct bfd_symbol *symbol;
203     PTR data ATTRIBUTE_UNUSED;
204     asection *input_section;
205     bfd *output_bfd;
206     char **error_message ATTRIBUTE_UNUSED;
207{
208  bfd_vma relocation, pc;
209
210  /* If this is a partial relocation, just continue.  */
211  if (output_bfd != (bfd *)NULL)
212    return bfd_reloc_continue;
213
214  /* If this is an undefined symbol, return error */
215  if (bfd_is_und_section (symbol->section)
216      && (symbol->flags & BSF_WEAK) == 0)
217    return bfd_reloc_undefined;
218
219  /* Work out which section the relocation is targeted at and the
220     initial relocation command value.  */
221  if (bfd_is_com_section (symbol->section))
222    relocation = 0;
223  else
224    relocation = symbol->value;
225
226  relocation += symbol->section->output_section->vma;
227  relocation += symbol->section->output_offset;
228  relocation += reloc_entry->addend;
229
230  pc = input_section->output_section->vma + input_section->output_offset +
231    reloc_entry->address + 4;
232
233  if ((relocation & 0xF0000000) != (pc & 0xF0000000))
234    return bfd_reloc_overflow;
235
236  return bfd_reloc_continue;
237}
238
239/* This is only called when performing a BFD_RELOC_HI16_S relocation.
240   We need to see if bit 15 is set in the result. If it is, we add
241   0x10000 and continue normally. This will compensate for the sign extension
242   when the low bits are added at run time.  */
243
244static bfd_reloc_status_type
245mips_fix_hi16_s PARAMS ((bfd *, arelent *, asymbol *, PTR,
246			 asection *, bfd *, char **));
247
248static bfd_reloc_status_type
249mips_fix_hi16_s (abfd, reloc_entry, symbol, data, input_section,
250		 output_bfd, error_message)
251     bfd *abfd ATTRIBUTE_UNUSED;
252     arelent *reloc_entry;
253     asymbol *symbol;
254     PTR data ATTRIBUTE_UNUSED;
255     asection *input_section ATTRIBUTE_UNUSED;
256     bfd *output_bfd;
257     char **error_message ATTRIBUTE_UNUSED;
258{
259  bfd_vma relocation;
260
261  /* If this is a partial relocation, just continue.  */
262  if (output_bfd != (bfd *)NULL)
263    return bfd_reloc_continue;
264
265  /* If this is an undefined symbol, return error.  */
266  if (bfd_is_und_section (symbol->section)
267      && (symbol->flags & BSF_WEAK) == 0)
268    return bfd_reloc_undefined;
269
270  /* Work out which section the relocation is targeted at and the
271     initial relocation command value.  */
272  if (bfd_is_com_section (symbol->section))
273    relocation = 0;
274  else
275    relocation = symbol->value;
276
277  relocation += symbol->section->output_section->vma;
278  relocation += symbol->section->output_offset;
279  relocation += reloc_entry->addend;
280
281  if (relocation & 0x8000)
282    reloc_entry->addend += 0x10000;
283
284  return bfd_reloc_continue;
285}
286
287static reloc_howto_type mips_howto_table_ext[] = {
288  {MIPS_RELOC_32,      0, 2, 32, FALSE, 0,  complain_overflow_bitfield, 0,
289	"32",       FALSE, 0, 0xffffffff, FALSE},
290  {MIPS_RELOC_JMP,     2, 2, 26, FALSE, 0, complain_overflow_dont,
291	mips_fix_jmp_addr,
292	"MIPS_JMP", FALSE, 0, 0x03ffffff, FALSE},
293  {MIPS_RELOC_WDISP16, 2, 2, 16, TRUE,  0, complain_overflow_signed, 0,
294	"WDISP16",  FALSE, 0, 0x0000ffff, FALSE},
295  {MIPS_RELOC_HI16,   16, 2, 16, FALSE, 0, complain_overflow_bitfield, 0,
296	"HI16",     FALSE, 0, 0x0000ffff, FALSE},
297  {MIPS_RELOC_HI16_S, 16, 2, 16, FALSE, 0, complain_overflow_bitfield,
298        mips_fix_hi16_s,
299        "HI16_S",   FALSE, 0, 0x0000ffff, FALSE},
300  {MIPS_RELOC_LO16,    0, 2, 16, FALSE, 0, complain_overflow_dont, 0,
301	"LO16",     FALSE, 0, 0x0000ffff, FALSE},
302};
303
304static reloc_howto_type *
305MY(reloc_howto_type_lookup) (abfd, code)
306     bfd *abfd;
307     bfd_reloc_code_real_type code;
308{
309
310  if (bfd_get_arch (abfd) != bfd_arch_mips)
311    return 0;
312
313  switch (code)
314    {
315    case BFD_RELOC_CTOR:
316    case BFD_RELOC_32:
317      return (&mips_howto_table_ext[MIPS_RELOC_32]);
318    case BFD_RELOC_MIPS_JMP:
319      return (&mips_howto_table_ext[MIPS_RELOC_JMP]);
320    case BFD_RELOC_16_PCREL_S2:
321      return (&mips_howto_table_ext[MIPS_RELOC_WDISP16]);
322    case BFD_RELOC_HI16:
323      return (&mips_howto_table_ext[MIPS_RELOC_HI16]);
324    case BFD_RELOC_HI16_S:
325      return (&mips_howto_table_ext[MIPS_RELOC_HI16_S]);
326    case BFD_RELOC_LO16:
327      return (&mips_howto_table_ext[MIPS_RELOC_LO16]);
328    default:
329      return 0;
330    }
331}
332
333/* This is just like the standard aoutx.h version but we need to do our
334   own mapping of external reloc type values to howto entries.  */
335long
336MY(canonicalize_reloc) (abfd, section, relptr, symbols)
337      bfd *abfd;
338      sec_ptr section;
339      arelent **relptr;
340      asymbol **symbols;
341{
342  arelent *tblptr = section->relocation;
343  unsigned int count, c;
344  extern reloc_howto_type NAME(aout,ext_howto_table)[];
345
346  /* If we have already read in the relocation table, return the values.  */
347  if (section->flags & SEC_CONSTRUCTOR)
348    {
349      arelent_chain *chain = section->constructor_chain;
350
351      for (count = 0; count < section->reloc_count; count++)
352	{
353	  *relptr++ = &chain->relent;
354	  chain = chain->next;
355	}
356      *relptr = 0;
357      return section->reloc_count;
358    }
359
360  if (tblptr && section->reloc_count)
361    {
362      for (count = 0; count++ < section->reloc_count;)
363	*relptr++ = tblptr++;
364      *relptr = 0;
365      return section->reloc_count;
366    }
367
368  if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
369    return -1;
370  tblptr = section->relocation;
371
372  /* fix up howto entries.  */
373  for (count = 0; count++ < section->reloc_count;)
374    {
375      c = tblptr->howto - NAME(aout,ext_howto_table);
376      tblptr->howto = &mips_howto_table_ext[c];
377
378      *relptr++ = tblptr++;
379    }
380  *relptr = 0;
381  return section->reloc_count;
382}
383
384static const struct aout_backend_data MY(backend_data) = {
385  0,				/* zmagic contiguous */
386  1,				/* text incl header */
387  0,				/* entry is text address */
388  0,				/* exec_hdr_flags */
389  TARGET_PAGE_SIZE,			/* text vma */
390  MY_set_sizes,
391  0,				/* text size includes exec header */
392  0,				/* add_dynamic_symbols */
393  0,				/* add_one_symbol */
394  0,				/* link_dynamic_object */
395  0,				/* write_dynamic_symbol */
396  0,				/* check_dynamic_reloc */
397  0				/* finish_dynamic_link */
398};
399
400extern const bfd_target aout_mips_big_vec;
401
402const bfd_target aout_mips_little_vec =
403  {
404    "a.out-mips-little",		/* name */
405    bfd_target_aout_flavour,
406    BFD_ENDIAN_LITTLE,		/* target byte order (little) */
407    BFD_ENDIAN_LITTLE,		/* target headers byte order (little) */
408    (HAS_RELOC | EXEC_P |		/* object flags */
409     HAS_LINENO | HAS_DEBUG |
410     HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
411    (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
412    MY_symbol_leading_char,
413    ' ',				/* ar_pad_char */
414    15,				/* ar_max_namelen */
415    bfd_getl64, bfd_getl_signed_64, bfd_putl64,
416    bfd_getl32, bfd_getl_signed_32, bfd_putl32,
417    bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
418    bfd_getl64, bfd_getl_signed_64, bfd_putl64,
419    bfd_getl32, bfd_getl_signed_32, bfd_putl32,
420    bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
421    {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
422     bfd_generic_archive_p, MY_core_file_p},
423    {bfd_false, MY_mkobject,	/* bfd_set_format */
424     _bfd_generic_mkarchive, bfd_false},
425    {bfd_false, MY_write_object_contents, /* bfd_write_contents */
426     _bfd_write_archive_contents, bfd_false},
427
428    BFD_JUMP_TABLE_GENERIC (MY),
429    BFD_JUMP_TABLE_COPY (MY),
430    BFD_JUMP_TABLE_CORE (MY),
431    BFD_JUMP_TABLE_ARCHIVE (MY),
432    BFD_JUMP_TABLE_SYMBOLS (MY),
433    BFD_JUMP_TABLE_RELOCS (MY),
434    BFD_JUMP_TABLE_WRITE (MY),
435    BFD_JUMP_TABLE_LINK (MY),
436    BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
437
438    & aout_mips_big_vec,
439
440    (PTR) MY_backend_data
441  };
442
443const bfd_target aout_mips_big_vec =
444  {
445    "a.out-mips-big",		/* name */
446    bfd_target_aout_flavour,
447    BFD_ENDIAN_BIG,		/* target byte order (big) */
448    BFD_ENDIAN_BIG,		/* target headers byte order (big) */
449    (HAS_RELOC | EXEC_P |		/* object flags */
450     HAS_LINENO | HAS_DEBUG |
451     HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
452    (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
453    MY_symbol_leading_char,
454    ' ',				/* ar_pad_char */
455    15,				/* ar_max_namelen */
456    bfd_getb64, bfd_getb_signed_64, bfd_putb64,
457    bfd_getb32, bfd_getb_signed_32, bfd_putb32,
458    bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
459    bfd_getb64, bfd_getb_signed_64, bfd_putb64,
460    bfd_getb32, bfd_getb_signed_32, bfd_putb32,
461    bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
462    {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
463     bfd_generic_archive_p, MY_core_file_p},
464    {bfd_false, MY_mkobject,	/* bfd_set_format */
465     _bfd_generic_mkarchive, bfd_false},
466    {bfd_false, MY_write_object_contents, /* bfd_write_contents */
467     _bfd_write_archive_contents, bfd_false},
468
469    BFD_JUMP_TABLE_GENERIC (MY),
470    BFD_JUMP_TABLE_COPY (MY),
471    BFD_JUMP_TABLE_CORE (MY),
472    BFD_JUMP_TABLE_ARCHIVE (MY),
473    BFD_JUMP_TABLE_SYMBOLS (MY),
474    BFD_JUMP_TABLE_RELOCS (MY),
475    BFD_JUMP_TABLE_WRITE (MY),
476    BFD_JUMP_TABLE_LINK (MY),
477    BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
478
479    & aout_mips_little_vec,
480
481    (PTR) MY_backend_data
482  };
483