aout-arm.c revision 60484
1/* BFD back-end for raw ARM a.out binaries.
2   Copyright (C) 1994, 95, 96, 97, 98, 1999 Free Software Foundation, Inc.
3   Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
4
5This file is part of BFD, the Binary File Descriptor library.
6
7This program is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2 of the License, or
10(at your option) any later version.
11
12This program is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with this program; if not, write to the Free Software
19Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
20
21
22#define N_TXTADDR(x) \
23  ((N_MAGIC(x) == NMAGIC) ? 0x8000 : \
24   (N_MAGIC(x) != ZMAGIC) ? 0 : \
25   (N_SHARED_LIB(x)) ? ((x).a_entry & ~(TARGET_PAGE_SIZE - 1)) : \
26   TEXT_START_ADDR)
27
28#define TEXT_START_ADDR 0x8000
29#define TARGET_PAGE_SIZE 0x8000
30#define SEGMENT_SIZE TARGET_PAGE_SIZE
31#define DEFAULT_ARCH bfd_arch_arm
32
33#define MY(OP) CAT(aoutarm_,OP)
34#define N_BADMAG(x) ((((x).a_info & ~007200) != ZMAGIC) && \
35                     (((x).a_info & ~006000) != OMAGIC) && \
36                     ((x).a_info != NMAGIC))
37#define N_MAGIC(x) ((x).a_info & ~07200)
38
39#include "bfd.h"
40#include "sysdep.h"
41
42#define MYARM(OP) CAT(aoutarm_,OP)
43reloc_howto_type 	*MYARM(bfd_reloc_type_lookup)
44				PARAMS((bfd *, bfd_reloc_code_real_type));
45static boolean 		MYARM(write_object_contents)	PARAMS((bfd *));
46
47/* Avoid multiple defininitions from aoutx if supporting standarad a.out
48   as well as our own.  */
49#define NAME(x,y) CAT3(aoutarm,_32_,y)
50
51#define MY_bfd_reloc_type_lookup aoutarm_bfd_reloc_type_lookup
52
53#include "libaout.h"
54#include "aout/aout64.h"
55
56static bfd_reloc_status_type
57MY(fix_pcrel_26_done)	PARAMS ((bfd *, arelent *, asymbol *, PTR,
58				 asection *, bfd *, char **));
59
60static bfd_reloc_status_type
61MY(fix_pcrel_26)	 PARAMS ((bfd *, arelent *, asymbol *, PTR,
62				  asection *, bfd *, char **));
63static void MY(swap_std_reloc_in) PARAMS ((bfd *, struct reloc_std_external *,
64					   arelent *, asymbol **,
65					   bfd_size_type));
66void MY(swap_std_reloc_out) PARAMS ((bfd *, arelent *,
67				     struct reloc_std_external *));
68
69reloc_howto_type MY(howto_table)[] =
70{
71  /* type rs size bsz pcrel bitpos ovrf sf name part_inpl readmask setmask
72     pcdone */
73  HOWTO (0, 0, 0, 8, false, 0, complain_overflow_bitfield, 0, "8", true,
74	 0x000000ff, 0x000000ff, false),
75  HOWTO (1, 0, 1, 16, false, 0, complain_overflow_bitfield, 0, "16", true,
76	 0x0000ffff, 0x0000ffff, false),
77  HOWTO (2, 0, 2, 32, false, 0, complain_overflow_bitfield, 0, "32", true,
78	 0xffffffff, 0xffffffff, false),
79  HOWTO (3, 2, 2, 26, true, 0, complain_overflow_signed, MY(fix_pcrel_26),
80	 "ARM26", true, 0x00ffffff, 0x00ffffff, true),
81  HOWTO (4, 0, 0, 8, true, 0, complain_overflow_signed, 0, "DISP8", true,
82	 0x000000ff, 0x000000ff, true),
83  HOWTO (5, 0, 1, 16, true, 0, complain_overflow_signed, 0, "DISP16", true,
84	 0x0000ffff, 0x0000ffff, true),
85  HOWTO (6, 0, 2, 32, true, 0, complain_overflow_signed, 0, "DISP32", true,
86	 0xffffffff, 0xffffffff, true),
87  HOWTO (7, 2, 2, 26, false, 0, complain_overflow_signed,
88	 MY(fix_pcrel_26_done), "ARM26D", true, 0x0, 0x0,
89	 false),
90  EMPTY_HOWTO (-1),
91  HOWTO (9, 0, -1, 16, false, 0, complain_overflow_bitfield, 0, "NEG16", true,
92	 0x0000ffff, 0x0000ffff, false),
93  HOWTO (10, 0, -2, 32, false, 0, complain_overflow_bitfield, 0, "NEG32", true,
94	 0xffffffff, 0xffffffff, false)
95};
96
97#define RELOC_ARM_BITS_NEG_BIG      ((unsigned int) 0x08)
98#define RELOC_ARM_BITS_NEG_LITTLE   ((unsigned int) 0x10)
99
100reloc_howto_type *
101MY(reloc_howto)(abfd, rel, r_index, r_extern, r_pcrel)
102     bfd *abfd;
103     struct reloc_std_external *rel;
104     int *r_index;
105     int *r_extern;
106     int *r_pcrel;
107{
108  unsigned int r_length;
109  unsigned int r_pcrel_done;
110  unsigned int r_neg;
111  int index;
112
113  *r_pcrel = 0;
114  if (bfd_header_big_endian (abfd))
115    {
116      *r_index     =  ((rel->r_index[0] << 16)
117		       | (rel->r_index[1] << 8)
118		       | rel->r_index[2]);
119      *r_extern    = (0 != (rel->r_type[0] & RELOC_STD_BITS_EXTERN_BIG));
120      r_pcrel_done = (0 != (rel->r_type[0] & RELOC_STD_BITS_PCREL_BIG));
121      r_neg 	   = (0 != (rel->r_type[0] & RELOC_ARM_BITS_NEG_BIG));
122      r_length     = ((rel->r_type[0] & RELOC_STD_BITS_LENGTH_BIG)
123		      >> RELOC_STD_BITS_LENGTH_SH_BIG);
124    }
125  else
126    {
127      *r_index     = ((rel->r_index[2] << 16)
128		      | (rel->r_index[1] << 8)
129		      | rel->r_index[0]);
130      *r_extern    = (0 != (rel->r_type[0] & RELOC_STD_BITS_EXTERN_LITTLE));
131      r_pcrel_done = (0 != (rel->r_type[0] & RELOC_STD_BITS_PCREL_LITTLE));
132      r_neg 	   = (0 != (rel->r_type[0] & RELOC_ARM_BITS_NEG_LITTLE));
133      r_length     = ((rel->r_type[0] & RELOC_STD_BITS_LENGTH_LITTLE)
134		      >> RELOC_STD_BITS_LENGTH_SH_LITTLE);
135    }
136  index = r_length + 4 * r_pcrel_done + 8 * r_neg;
137  if (index == 3)
138    *r_pcrel = 1;
139
140  return MY(howto_table) + index;
141}
142
143#define MY_reloc_howto(BFD, REL, IN, EX, PC) \
144	MY(reloc_howto) (BFD, REL, &IN, &EX, &PC)
145
146void
147MY(put_reloc)(abfd, r_extern, r_index, value, howto, reloc)
148     bfd *abfd;
149     int r_extern;
150     int r_index;
151     long value;
152     reloc_howto_type *howto;
153     struct reloc_std_external *reloc;
154{
155  unsigned int r_length;
156  int r_pcrel;
157  int r_neg;
158
159  PUT_WORD (abfd, value, reloc->r_address);
160  r_length = howto->size ;	/* Size as a power of two */
161
162  /* Special case for branch relocations. */
163  if (howto->type == 3 || howto->type == 7)
164    r_length = 3;
165
166  r_pcrel  = howto->type & 4; 	/* PC Relative done? */
167  r_neg = howto->type & 8;	/* Negative relocation */
168  if (bfd_header_big_endian (abfd))
169    {
170      reloc->r_index[0] = r_index >> 16;
171      reloc->r_index[1] = r_index >> 8;
172      reloc->r_index[2] = r_index;
173      reloc->r_type[0] =
174	((r_extern ?     RELOC_STD_BITS_EXTERN_BIG : 0)
175	 | (r_pcrel ?    RELOC_STD_BITS_PCREL_BIG : 0)
176	 | (r_neg ?	 RELOC_ARM_BITS_NEG_BIG : 0)
177	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_BIG));
178    }
179  else
180    {
181      reloc->r_index[2] = r_index >> 16;
182      reloc->r_index[1] = r_index >> 8;
183      reloc->r_index[0] = r_index;
184      reloc->r_type[0] =
185	((r_extern ?     RELOC_STD_BITS_EXTERN_LITTLE : 0)
186	 | (r_pcrel ?    RELOC_STD_BITS_PCREL_LITTLE : 0)
187	 | (r_neg ?	 RELOC_ARM_BITS_NEG_LITTLE : 0)
188	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_LITTLE));
189    }
190}
191
192#define MY_put_reloc(BFD, EXT, IDX, VAL, HOWTO, RELOC) \
193  MY(put_reloc)(BFD, EXT, IDX, VAL, HOWTO, RELOC)
194
195void
196MY(relocatable_reloc)(howto, abfd, reloc, amount, r_addr)
197     reloc_howto_type *howto;
198     bfd *abfd;
199     struct reloc_std_external *reloc;
200     bfd_vma *amount;
201     bfd_vma r_addr;
202{
203  if (howto->type == 3)
204    {
205      if (reloc->r_type[0]
206	  & (bfd_header_big_endian (abfd)
207	     ? RELOC_STD_BITS_EXTERN_BIG : RELOC_STD_BITS_EXTERN_LITTLE))
208	{
209	  /* The reloc is still external, so don't modify anything. */
210	  *amount = 0;
211	}
212      else
213	{
214	  *amount -= r_addr;
215	  /* Change the r_pcrel value -- on the ARM, this bit is set once the
216	     relocation is done.  */
217	  if (bfd_header_big_endian (abfd))
218	    reloc->r_type[0] |= RELOC_STD_BITS_PCREL_BIG;
219	  else
220	    reloc->r_type[0] |= RELOC_STD_BITS_PCREL_LITTLE;
221	}
222    }
223  else if (howto->type == 7)
224    *amount = 0;
225}
226
227#define MY_relocatable_reloc(HOW, BFD, REL, AMOUNT, ADDR) \
228  MY(relocatable_reloc)(HOW, BFD, REL, &(AMOUNT), ADDR)
229
230static bfd_reloc_status_type
231MY(fix_pcrel_26_done) (abfd, reloc_entry, symbol, data, input_section,
232		       output_bfd, error_message)
233     bfd *abfd ATTRIBUTE_UNUSED;
234     arelent *reloc_entry ATTRIBUTE_UNUSED;
235     asymbol *symbol ATTRIBUTE_UNUSED;
236     PTR data ATTRIBUTE_UNUSED;
237     asection *input_section ATTRIBUTE_UNUSED;
238     bfd *output_bfd ATTRIBUTE_UNUSED;
239     char **error_message ATTRIBUTE_UNUSED;
240{
241  /* This is dead simple at present.  */
242  return bfd_reloc_ok;
243}
244
245static bfd_reloc_status_type
246MY(fix_pcrel_26) (abfd, reloc_entry, symbol, data, input_section,
247		  output_bfd, error_message)
248     bfd *abfd;
249     arelent *reloc_entry;
250     asymbol *symbol;
251     PTR data;
252     asection *input_section;
253     bfd *output_bfd;
254     char **error_message ATTRIBUTE_UNUSED;
255{
256  bfd_vma relocation;
257  bfd_size_type addr = reloc_entry->address;
258  long target = bfd_get_32 (abfd, (bfd_byte *) data + addr);
259  bfd_reloc_status_type flag = bfd_reloc_ok;
260
261  /* If this is an undefined symbol, return error */
262  if (symbol->section == &bfd_und_section
263      && (symbol->flags & BSF_WEAK) == 0)
264    return output_bfd ? bfd_reloc_ok : bfd_reloc_undefined;
265
266  /* If the sections are different, and we are doing a partial relocation,
267     just ignore it for now.  */
268  if (symbol->section->name != input_section->name
269      && output_bfd != (bfd *)NULL)
270    return bfd_reloc_ok;
271
272  relocation = (target & 0x00ffffff) << 2;
273  relocation = (relocation ^ 0x02000000) - 0x02000000; /* Sign extend */
274  relocation += symbol->value;
275  relocation += symbol->section->output_section->vma;
276  relocation += symbol->section->output_offset;
277  relocation += reloc_entry->addend;
278  relocation -= input_section->output_section->vma;
279  relocation -= input_section->output_offset;
280  relocation -= addr;
281  if (relocation & 3)
282    return bfd_reloc_overflow;
283
284  /* Check for overflow */
285  if (relocation & 0x02000000)
286    {
287      if ((relocation & ~ (bfd_vma) 0x03ffffff) != ~ (bfd_vma) 0x03ffffff)
288	flag = bfd_reloc_overflow;
289    }
290  else if (relocation & ~0x03ffffff)
291    flag = bfd_reloc_overflow;
292
293  target &= ~0x00ffffff;
294  target |= (relocation >> 2) & 0x00ffffff;
295  bfd_put_32 (abfd, target, (bfd_byte *) data + addr);
296
297  /* Now the ARM magic... Change the reloc type so that it is marked as done.
298     Strictly this is only necessary if we are doing a partial relocation.  */
299  reloc_entry->howto = &MY(howto_table)[7];
300
301  return flag;
302}
303
304reloc_howto_type *
305MY(bfd_reloc_type_lookup)(abfd,code)
306     bfd *abfd;
307     bfd_reloc_code_real_type code;
308{
309#define ASTD(i,j)       case i: return &MY(howto_table)[j]
310  if (code == BFD_RELOC_CTOR)
311    switch (bfd_get_arch_info (abfd)->bits_per_address)
312      {
313      case 32:
314        code = BFD_RELOC_32;
315        break;
316      default: return (CONST struct reloc_howto_struct *) 0;
317      }
318
319  switch (code)
320    {
321      ASTD (BFD_RELOC_16, 1);
322      ASTD (BFD_RELOC_32, 2);
323      ASTD (BFD_RELOC_ARM_PCREL_BRANCH, 3);
324      ASTD (BFD_RELOC_8_PCREL, 4);
325      ASTD (BFD_RELOC_16_PCREL, 5);
326      ASTD (BFD_RELOC_32_PCREL, 6);
327    default: return (CONST struct reloc_howto_struct *) 0;
328    }
329}
330
331#define MY_swap_std_reloc_in MY(swap_std_reloc_in)
332#define MY_swap_std_reloc_out MY(swap_std_reloc_out)
333#define MY_get_section_contents _bfd_generic_get_section_contents
334/* #define MY_bfd_link_hash_table_create _bfd_generic_link_hash_table_create */
335/* #define MY_bfd_link_add_symbols _bfd_generic_link_add_symbols */
336/* #define MY_bfd_final_link _bfd_generic_final_link */
337
338#include "aoutx.h"
339
340static void
341MY_swap_std_reloc_in (abfd, bytes, cache_ptr, symbols, symcount)
342     bfd *abfd;
343     struct reloc_std_external *bytes;
344     arelent *cache_ptr;
345     asymbol **symbols;
346     bfd_size_type symcount ATTRIBUTE_UNUSED;
347{
348  int r_index;
349  int r_extern;
350  int r_pcrel;
351  struct aoutdata *su = &(abfd->tdata.aout_data->a);
352
353  cache_ptr->address = bfd_h_get_32 (abfd, bytes->r_address);
354
355  cache_ptr->howto = MY_reloc_howto (abfd, bytes, r_index, r_extern, r_pcrel);
356
357  MOVE_ADDRESS (0);
358}
359
360void
361MY_swap_std_reloc_out (abfd, g, natptr)
362     bfd *abfd;
363     arelent *g;
364     struct reloc_std_external *natptr;
365{
366  int r_index;
367  asymbol *sym = *(g->sym_ptr_ptr);
368  int r_extern;
369  int r_length;
370  int r_pcrel;
371  int r_neg = 0;	/* Negative relocs use the BASEREL bit.  */
372  asection *output_section = sym->section->output_section;
373
374  PUT_WORD(abfd, g->address, natptr->r_address);
375
376  r_length = g->howto->size ;   /* Size as a power of two */
377  if (r_length < 0)
378    {
379      r_length = -r_length;
380      r_neg = 1;
381    }
382
383  r_pcrel  = (int) g->howto->pc_relative; /* Relative to PC? */
384
385  /* For RISC iX, in pc-relative relocs the r_pcrel bit means that the
386     relocation has been done already (Only for the 26-bit one I think)???!!!
387     */
388
389  if (g->howto->type == 3)
390    {
391      r_length = 3;
392      r_pcrel = 0;
393    }
394  else if (g->howto->type == 7)
395    {
396      r_length = 3;
397      r_pcrel = 1;
398    }
399
400
401#if 0
402  /* For a standard reloc, the addend is in the object file.  */
403  r_addend = g->addend + (*(g->sym_ptr_ptr))->section->output_section->vma;
404#endif
405
406  /* name was clobbered by aout_write_syms to be symbol index */
407
408  /* If this relocation is relative to a symbol then set the
409     r_index to the symbols index, and the r_extern bit.
410
411     Absolute symbols can come in in two ways, either as an offset
412     from the abs section, or as a symbol which has an abs value.
413     check for that here
414     */
415
416  if (bfd_is_com_section (output_section)
417      || output_section == &bfd_abs_section
418      || output_section == &bfd_und_section)
419    {
420      if (bfd_abs_section.symbol == sym)
421	{
422	  /* Whoops, looked like an abs symbol, but is really an offset
423	     from the abs section */
424	  r_index = 0;
425	  r_extern = 0;
426	}
427      else
428	{
429	  /* Fill in symbol */
430	  r_extern = 1;
431	  r_index = (*(g->sym_ptr_ptr))->KEEPIT;
432	}
433    }
434  else
435    {
436      /* Just an ordinary section */
437      r_extern = 0;
438      r_index  = output_section->target_index;
439    }
440
441  /* now the fun stuff */
442  if (bfd_header_big_endian (abfd))
443    {
444      natptr->r_index[0] = r_index >> 16;
445      natptr->r_index[1] = r_index >> 8;
446      natptr->r_index[2] = r_index;
447      natptr->r_type[0] =
448	(  (r_extern ?   RELOC_STD_BITS_EXTERN_BIG: 0)
449	 | (r_pcrel  ?   RELOC_STD_BITS_PCREL_BIG: 0)
450	 | (r_neg    ?   RELOC_ARM_BITS_NEG_BIG: 0)
451	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_BIG));
452    }
453  else
454    {
455      natptr->r_index[2] = r_index >> 16;
456      natptr->r_index[1] = r_index >> 8;
457      natptr->r_index[0] = r_index;
458      natptr->r_type[0] =
459	(  (r_extern ?   RELOC_STD_BITS_EXTERN_LITTLE: 0)
460	 | (r_pcrel  ?   RELOC_STD_BITS_PCREL_LITTLE: 0)
461	 | (r_neg    ?   RELOC_ARM_BITS_NEG_LITTLE: 0)
462	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_LITTLE));
463    }
464}
465
466#define MY_BFD_TARGET
467
468#include "aout-target.h"
469
470extern const bfd_target aout_arm_big_vec;
471
472const bfd_target aout_arm_little_vec =
473{
474  "a.out-arm-little",           /* name */
475  bfd_target_aout_flavour,
476  BFD_ENDIAN_LITTLE,            /* target byte order (little) */
477  BFD_ENDIAN_LITTLE,            /* target headers byte order (little) */
478  (HAS_RELOC | EXEC_P |         /* object flags */
479   HAS_LINENO | HAS_DEBUG |
480   HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED),
481  (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
482  MY_symbol_leading_char,
483  AR_PAD_CHAR,                  /* ar_pad_char */
484  15,                           /* ar_max_namelen */
485  bfd_getl64, bfd_getl_signed_64, bfd_putl64,
486     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
487     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
488  bfd_getl64, bfd_getl_signed_64, bfd_putl64,
489     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
490     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
491    {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
492       bfd_generic_archive_p, MY_core_file_p},
493    {bfd_false, MY_mkobject,    /* bfd_set_format */
494       _bfd_generic_mkarchive, bfd_false},
495    {bfd_false, MY_write_object_contents, /* bfd_write_contents */
496       _bfd_write_archive_contents, bfd_false},
497
498     BFD_JUMP_TABLE_GENERIC (MY),
499     BFD_JUMP_TABLE_COPY (MY),
500     BFD_JUMP_TABLE_CORE (MY),
501     BFD_JUMP_TABLE_ARCHIVE (MY),
502     BFD_JUMP_TABLE_SYMBOLS (MY),
503     BFD_JUMP_TABLE_RELOCS (MY),
504     BFD_JUMP_TABLE_WRITE (MY),
505     BFD_JUMP_TABLE_LINK (MY),
506     BFD_JUMP_TABLE_DYNAMIC (MY),
507
508  & aout_arm_big_vec,
509
510  (PTR) MY_backend_data,
511};
512
513const bfd_target aout_arm_big_vec =
514{
515  "a.out-arm-big",           /* name */
516  bfd_target_aout_flavour,
517  BFD_ENDIAN_BIG,               /* target byte order (big) */
518  BFD_ENDIAN_BIG,               /* target headers byte order (big) */
519  (HAS_RELOC | EXEC_P |         /* object flags */
520   HAS_LINENO | HAS_DEBUG |
521   HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED),
522  (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_CODE | SEC_DATA),
523  MY_symbol_leading_char,
524  AR_PAD_CHAR,                  /* ar_pad_char */
525  15,                           /* ar_max_namelen */
526  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
527     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
528     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
529  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
530     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
531     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
532    {_bfd_dummy_target, MY_object_p, /* bfd_check_format */
533       bfd_generic_archive_p, MY_core_file_p},
534    {bfd_false, MY_mkobject,    /* bfd_set_format */
535       _bfd_generic_mkarchive, bfd_false},
536    {bfd_false, MY_write_object_contents, /* bfd_write_contents */
537       _bfd_write_archive_contents, bfd_false},
538
539     BFD_JUMP_TABLE_GENERIC (MY),
540     BFD_JUMP_TABLE_COPY (MY),
541     BFD_JUMP_TABLE_CORE (MY),
542     BFD_JUMP_TABLE_ARCHIVE (MY),
543     BFD_JUMP_TABLE_SYMBOLS (MY),
544     BFD_JUMP_TABLE_RELOCS (MY),
545     BFD_JUMP_TABLE_WRITE (MY),
546     BFD_JUMP_TABLE_LINK (MY),
547     BFD_JUMP_TABLE_DYNAMIC (MY),
548
549  & aout_arm_little_vec,
550
551  (PTR) MY_backend_data,
552};
553