1 /* BFD back-end for Motorola 68000 COFF binaries.
2 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999,
3 2000, 2001, 2002, 2003, 2005, 2007
4 Free Software Foundation, Inc.
5 Written by Cygnus Support.
7 This file is part of BFD, the Binary File Descriptor library.
9 This program 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 of the License, or
12 (at your option) any later version.
14 This program 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.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
26 #include "coff/m68k.h"
27 #include "coff/internal.h"
30 /* This source file is compiled multiple times for various m68k COFF
31 variants. The following macros control its behaviour:
34 The C name of the BFD target vector. The default is m68kcoff_vec.
36 The user visible target name. The default is "coff-m68k".
38 Whether symbol names have an underscore.
40 Only declare the relocation howto array. Don't actually compile
41 it. The actual array will be picked up in another version of the
44 Make the relocation howto array, and associated functions, static.
46 If this is defined, then, for a relocation against a common
47 symbol, the object file holds the value (the size) of the common
48 symbol. If this is not defined, then, for a relocation against a
49 common symbol, the object file holds zero. */
51 #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
53 #ifndef COFF_PAGE_SIZE
54 /* The page size is a guess based on ELF. */
55 #define COFF_PAGE_SIZE 0x2000
58 #ifndef COFF_COMMON_ADDEND
59 #define RELOC_SPECIAL_FN 0
61 static bfd_reloc_status_type m68kcoff_common_addend_special_fn
62 PARAMS ((bfd
*, arelent
*, asymbol
*, PTR
, asection
*, bfd
*, char **));
63 static reloc_howto_type
*m68kcoff_common_addend_rtype_to_howto
64 PARAMS ((bfd
*, asection
*, struct internal_reloc
*,
65 struct coff_link_hash_entry
*, struct internal_syment
*,
67 #define RELOC_SPECIAL_FN m68kcoff_common_addend_special_fn
70 static bfd_boolean m68k_coff_is_local_label_name
71 PARAMS ((bfd
*, const char *));
73 /* On the delta, a symbol starting with L% is local. We won't see
74 such a symbol on other platforms, so it should be safe to always
75 consider it local here. */
78 m68k_coff_is_local_label_name (abfd
, name
)
82 if (name
[0] == 'L' && name
[1] == '%')
85 return _bfd_coff_is_local_label_name (abfd
, name
);
89 /* Clean up namespace. */
90 #define m68kcoff_howto_table _bfd_m68kcoff_howto_table
91 #define m68k_rtype2howto _bfd_m68kcoff_rtype2howto
92 #define m68k_howto2rtype _bfd_m68kcoff_howto2rtype
93 #define m68k_reloc_type_lookup _bfd_m68kcoff_reloc_type_lookup
94 #define m68k_reloc_name_lookup _bfd_m68kcoff_reloc_name_lookup
97 #ifdef ONLY_DECLARE_RELOCS
98 extern reloc_howto_type m68kcoff_howto_table
[];
103 reloc_howto_type m68kcoff_howto_table
[] =
105 HOWTO (R_RELBYTE
, 0, 0, 8, FALSE
, 0, complain_overflow_bitfield
, RELOC_SPECIAL_FN
, "8", TRUE
, 0x000000ff,0x000000ff, FALSE
),
106 HOWTO (R_RELWORD
, 0, 1, 16, FALSE
, 0, complain_overflow_bitfield
, RELOC_SPECIAL_FN
, "16", TRUE
, 0x0000ffff,0x0000ffff, FALSE
),
107 HOWTO (R_RELLONG
, 0, 2, 32, FALSE
, 0, complain_overflow_bitfield
, RELOC_SPECIAL_FN
, "32", TRUE
, 0xffffffff,0xffffffff, FALSE
),
108 HOWTO (R_PCRBYTE
, 0, 0, 8, TRUE
, 0, complain_overflow_signed
, RELOC_SPECIAL_FN
, "DISP8", TRUE
, 0x000000ff,0x000000ff, FALSE
),
109 HOWTO (R_PCRWORD
, 0, 1, 16, TRUE
, 0, complain_overflow_signed
, RELOC_SPECIAL_FN
, "DISP16", TRUE
, 0x0000ffff,0x0000ffff, FALSE
),
110 HOWTO (R_PCRLONG
, 0, 2, 32, TRUE
, 0, complain_overflow_signed
, RELOC_SPECIAL_FN
, "DISP32", TRUE
, 0xffffffff,0xffffffff, FALSE
),
111 HOWTO (R_RELLONG_NEG
, 0, -2, 32, FALSE
, 0, complain_overflow_bitfield
, RELOC_SPECIAL_FN
, "-32", TRUE
, 0xffffffff,0xffffffff, FALSE
),
113 #endif /* not ONLY_DECLARE_RELOCS */
116 #define BADMAG(x) M68KBADMAG(x)
118 #define M68 1 /* Customize coffcode.h */
120 /* Turn a howto into a reloc number */
122 #ifdef ONLY_DECLARE_RELOCS
123 extern void m68k_rtype2howto
PARAMS ((arelent
*internal
, int relocentry
));
124 extern int m68k_howto2rtype
PARAMS ((reloc_howto_type
*));
125 extern reloc_howto_type
*m68k_reloc_type_lookup
126 PARAMS ((bfd
*, bfd_reloc_code_real_type
));
127 extern reloc_howto_type
*m68k_reloc_name_lookup
128 PARAMS ((bfd
*, const char *));
132 #define STAT_REL static
137 STAT_REL reloc_howto_type
* m68k_reloc_type_lookup
PARAMS ((bfd
*, bfd_reloc_code_real_type
));
138 STAT_REL reloc_howto_type
* m68k_reloc_name_lookup
PARAMS ((bfd
*, const char *));
139 STAT_REL
int m68k_howto2rtype
PARAMS ((reloc_howto_type
*));
140 STAT_REL
void m68k_rtype2howto
PARAMS ((arelent
*, int));
144 m68k_rtype2howto(internal
, relocentry
)
150 case R_RELBYTE
: internal
->howto
= m68kcoff_howto_table
+ 0; break;
151 case R_RELWORD
: internal
->howto
= m68kcoff_howto_table
+ 1; break;
152 case R_RELLONG
: internal
->howto
= m68kcoff_howto_table
+ 2; break;
153 case R_PCRBYTE
: internal
->howto
= m68kcoff_howto_table
+ 3; break;
154 case R_PCRWORD
: internal
->howto
= m68kcoff_howto_table
+ 4; break;
155 case R_PCRLONG
: internal
->howto
= m68kcoff_howto_table
+ 5; break;
156 case R_RELLONG_NEG
: internal
->howto
= m68kcoff_howto_table
+ 6; break;
161 m68k_howto2rtype (internal
)
162 reloc_howto_type
*internal
;
164 if (internal
->pc_relative
)
166 switch (internal
->bitsize
)
168 case 32: return R_PCRLONG
;
169 case 16: return R_PCRWORD
;
170 case 8: return R_PCRBYTE
;
175 switch (internal
->bitsize
)
177 case 32: return R_RELLONG
;
178 case 16: return R_RELWORD
;
179 case 8: return R_RELBYTE
;
185 STAT_REL reloc_howto_type
*
186 m68k_reloc_type_lookup (abfd
, code
)
187 bfd
*abfd ATTRIBUTE_UNUSED
;
188 bfd_reloc_code_real_type code
;
192 default: return NULL
;
193 case BFD_RELOC_8
: return m68kcoff_howto_table
+ 0;
194 case BFD_RELOC_16
: return m68kcoff_howto_table
+ 1;
196 case BFD_RELOC_32
: return m68kcoff_howto_table
+ 2;
197 case BFD_RELOC_8_PCREL
: return m68kcoff_howto_table
+ 3;
198 case BFD_RELOC_16_PCREL
: return m68kcoff_howto_table
+ 4;
199 case BFD_RELOC_32_PCREL
: return m68kcoff_howto_table
+ 5;
200 /* FIXME: There doesn't seem to be a code for R_RELLONG_NEG. */
205 STAT_REL reloc_howto_type
*
206 m68k_reloc_name_lookup (bfd
*abfd ATTRIBUTE_UNUSED
,
212 i
< sizeof (m68kcoff_howto_table
) / sizeof (m68kcoff_howto_table
[0]);
214 if (m68kcoff_howto_table
[i
].name
!= NULL
215 && strcasecmp (m68kcoff_howto_table
[i
].name
, r_name
) == 0)
216 return &m68kcoff_howto_table
[i
];
221 #endif /* not ONLY_DECLARE_RELOCS */
223 #define RTYPE2HOWTO(internal, relocentry) \
224 m68k_rtype2howto(internal, (relocentry)->r_type)
226 #define SELECT_RELOC(external, internal) \
227 external.r_type = m68k_howto2rtype (internal)
229 #define coff_bfd_reloc_type_lookup m68k_reloc_type_lookup
230 #define coff_bfd_reloc_name_lookup m68k_reloc_name_lookup
232 #ifndef COFF_COMMON_ADDEND
233 #ifndef coff_rtype_to_howto
235 #define coff_rtype_to_howto m68kcoff_rtype_to_howto
237 static reloc_howto_type
*m68kcoff_rtype_to_howto
238 PARAMS ((bfd
*, asection
*, struct internal_reloc
*,
239 struct coff_link_hash_entry
*, struct internal_syment
*,
242 static reloc_howto_type
*
243 m68kcoff_rtype_to_howto (abfd
, sec
, rel
, h
, sym
, addendp
)
244 bfd
*abfd ATTRIBUTE_UNUSED
;
246 struct internal_reloc
*rel
;
247 struct coff_link_hash_entry
*h ATTRIBUTE_UNUSED
;
248 struct internal_syment
*sym ATTRIBUTE_UNUSED
;
252 reloc_howto_type
*howto
;
254 RTYPE2HOWTO (&relent
, rel
);
256 howto
= relent
.howto
;
258 if (howto
->pc_relative
)
259 *addendp
+= sec
->vma
;
264 #endif /* ! defined (coff_rtype_to_howto) */
265 #endif /* ! defined (COFF_COMMON_ADDEND) */
267 #ifdef COFF_COMMON_ADDEND
269 /* If COFF_COMMON_ADDEND is defined, then when using m68k COFF the
270 value stored in the .text section for a reference to a common
271 symbol is the value itself plus any desired offset. (taken from
272 work done by Ian Taylor, Cygnus Support, for I386 COFF). */
274 /* If we are producing relocatable output, we need to do some
275 adjustments to the object file that are not done by the
276 bfd_perform_relocation function. This function is called by every
277 reloc type to make any required adjustments. */
279 static bfd_reloc_status_type
280 m68kcoff_common_addend_special_fn (abfd
, reloc_entry
, symbol
, data
,
281 input_section
, output_bfd
, error_message
)
283 arelent
*reloc_entry
;
286 asection
*input_section ATTRIBUTE_UNUSED
;
288 char **error_message ATTRIBUTE_UNUSED
;
292 if (output_bfd
== (bfd
*) NULL
)
293 return bfd_reloc_continue
;
295 if (bfd_is_com_section (symbol
->section
))
297 /* We are relocating a common symbol. The current value in the
298 object file is ORIG + OFFSET, where ORIG is the value of the
299 common symbol as seen by the object file when it was compiled
300 (this may be zero if the symbol was undefined) and OFFSET is
301 the offset into the common symbol (normally zero, but may be
302 non-zero when referring to a field in a common structure).
303 ORIG is the negative of reloc_entry->addend, which is set by
304 the CALC_ADDEND macro below. We want to replace the value in
305 the object file with NEW + OFFSET, where NEW is the value of
306 the common symbol which we are going to put in the final
307 object file. NEW is symbol->value. */
308 diff
= symbol
->value
+ reloc_entry
->addend
;
312 /* For some reason bfd_perform_relocation always effectively
313 ignores the addend for a COFF target when producing
314 relocatable output. This seems to be always wrong for 386
315 COFF, so we handle the addend here instead. */
316 diff
= reloc_entry
->addend
;
320 x = ((x & ~howto->dst_mask) | (((x & howto->src_mask) + diff) & howto->dst_mask))
324 reloc_howto_type
*howto
= reloc_entry
->howto
;
325 unsigned char *addr
= (unsigned char *) data
+ reloc_entry
->address
;
331 char x
= bfd_get_8 (abfd
, addr
);
333 bfd_put_8 (abfd
, x
, addr
);
339 short x
= bfd_get_16 (abfd
, addr
);
341 bfd_put_16 (abfd
, (bfd_vma
) x
, addr
);
347 long x
= bfd_get_32 (abfd
, addr
);
349 bfd_put_32 (abfd
, (bfd_vma
) x
, addr
);
358 /* Now let bfd_perform_relocation finish everything up. */
359 return bfd_reloc_continue
;
362 /* Compute the addend of a reloc. If the reloc is to a common symbol,
363 the object file contains the value of the common symbol. By the
364 time this is called, the linker may be using a different symbol
365 from a different object file with a different value. Therefore, we
366 hack wildly to locate the original symbol from this file so that we
367 can make the correct adjustment. This macro sets coffsym to the
368 symbol from the original file, and uses it to set the addend value
369 correctly. If this is not a common symbol, the usual addend
370 calculation is done, except that an additional tweak is needed for
372 FIXME: This macro refers to symbols and asect; these are from the
373 calling function, not the macro arguments. */
375 #define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \
377 coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \
378 if (ptr && bfd_asymbol_bfd (ptr) != abfd) \
379 coffsym = (obj_symbols (abfd) \
380 + (cache_ptr->sym_ptr_ptr - symbols)); \
382 coffsym = coff_symbol_from (abfd, ptr); \
383 if (coffsym != (coff_symbol_type *) NULL \
384 && coffsym->native->u.syment.n_scnum == 0) \
385 cache_ptr->addend = - coffsym->native->u.syment.n_value; \
386 else if (ptr && bfd_asymbol_bfd (ptr) == abfd \
387 && ptr->section != (asection *) NULL) \
388 cache_ptr->addend = - (ptr->section->vma + ptr->value); \
390 cache_ptr->addend = 0; \
391 if (ptr && (reloc.r_type == R_PCRBYTE \
392 || reloc.r_type == R_PCRWORD \
393 || reloc.r_type == R_PCRLONG)) \
394 cache_ptr->addend += asect->vma; \
397 #ifndef coff_rtype_to_howto
399 /* coff-m68k.c uses the special COFF backend linker. We need to
400 adjust common symbols. */
402 static reloc_howto_type
*
403 m68kcoff_common_addend_rtype_to_howto (abfd
, sec
, rel
, h
, sym
, addendp
)
404 bfd
*abfd ATTRIBUTE_UNUSED
;
406 struct internal_reloc
*rel
;
407 struct coff_link_hash_entry
*h
;
408 struct internal_syment
*sym
;
412 reloc_howto_type
*howto
;
414 RTYPE2HOWTO (&relent
, rel
);
416 howto
= relent
.howto
;
418 if (howto
->pc_relative
)
419 *addendp
+= sec
->vma
;
421 if (sym
!= NULL
&& sym
->n_scnum
== 0 && sym
->n_value
!= 0)
423 /* This is a common symbol. The section contents include the
424 size (sym->n_value) as an addend. The relocate_section
425 function will be adding in the final value of the symbol. We
426 need to subtract out the current size in order to get the
428 BFD_ASSERT (h
!= NULL
);
429 *addendp
-= sym
->n_value
;
432 /* If the output symbol is common (in which case this must be a
433 relocatable link), we need to add in the final size of the
435 if (h
!= NULL
&& h
->root
.type
== bfd_link_hash_common
)
436 *addendp
+= h
->root
.u
.c
.size
;
441 #define coff_rtype_to_howto m68kcoff_common_addend_rtype_to_howto
443 #endif /* ! defined (coff_rtype_to_howto) */
445 #endif /* COFF_COMMON_ADDEND */
447 #if !defined ONLY_DECLARE_RELOCS && ! defined STATIC_RELOCS
448 /* Given a .data section and a .emreloc in-memory section, store
449 relocation information into the .emreloc section which can be
450 used at runtime to relocate the section. This is called by the
451 linker when the --embedded-relocs switch is used. This is called
452 after the add_symbols entry point has been called for all the
453 objects, and before the final_link entry point is called. */
456 bfd_m68k_coff_create_embedded_relocs (abfd
, info
, datasec
, relsec
, errmsg
)
458 struct bfd_link_info
*info
;
464 bfd_size_type symesz
;
465 struct internal_reloc
*irel
, *irelend
;
469 BFD_ASSERT (! info
->relocatable
);
473 if (datasec
->reloc_count
== 0)
476 extsyms
= obj_coff_external_syms (abfd
);
477 symesz
= bfd_coff_symesz (abfd
);
479 irel
= _bfd_coff_read_internal_relocs (abfd
, datasec
, TRUE
, NULL
, FALSE
,
481 irelend
= irel
+ datasec
->reloc_count
;
483 amt
= (bfd_size_type
) datasec
->reloc_count
* 12;
484 relsec
->contents
= (bfd_byte
*) bfd_alloc (abfd
, amt
);
485 if (relsec
->contents
== NULL
)
488 p
= relsec
->contents
;
490 for (; irel
< irelend
; irel
++, p
+= 12)
494 /* We are going to write a four byte longword into the runtime
495 reloc section. The longword will be the address in the data
496 section which must be relocated. It is followed by the name
497 of the target section NUL-padded or truncated to 8
500 /* We can only relocate absolute longword relocs at run time. */
501 if (irel
->r_type
!= R_RELLONG
)
503 *errmsg
= _("unsupported reloc type");
504 bfd_set_error (bfd_error_bad_value
);
508 if (irel
->r_symndx
== -1)
509 targetsec
= bfd_abs_section_ptr
;
512 struct coff_link_hash_entry
*h
;
514 h
= obj_coff_sym_hashes (abfd
)[irel
->r_symndx
];
517 struct internal_syment isym
;
519 bfd_coff_swap_sym_in (abfd
, extsyms
+ symesz
* irel
->r_symndx
,
521 targetsec
= coff_section_from_bfd_index (abfd
, isym
.n_scnum
);
523 else if (h
->root
.type
== bfd_link_hash_defined
524 || h
->root
.type
== bfd_link_hash_defweak
)
525 targetsec
= h
->root
.u
.def
.section
;
531 (irel
->r_vaddr
- datasec
->vma
+ datasec
->output_offset
), p
);
532 memset (p
+ 4, 0, 8);
533 if (targetsec
!= NULL
)
534 strncpy ((char *) p
+ 4, targetsec
->output_section
->name
, 8);
539 #endif /* neither ONLY_DECLARE_RELOCS not STATIC_RELOCS */
541 #define coff_bfd_is_local_label_name m68k_coff_is_local_label_name
543 #define coff_relocate_section _bfd_coff_generic_relocate_section
545 #include "coffcode.h"
548 #define TARGET_SYM m68kcoff_vec
552 #define TARGET_NAME "coff-m68k"
555 #ifdef NAMES_HAVE_UNDERSCORE
556 CREATE_BIG_COFF_TARGET_VEC (TARGET_SYM
, TARGET_NAME
, D_PAGED
, 0, '_', NULL
, COFF_SWAP_TABLE
)
558 CREATE_BIG_COFF_TARGET_VEC (TARGET_SYM
, TARGET_NAME
, D_PAGED
, 0, 0, NULL
, COFF_SWAP_TABLE
)