1 /* Motorola MCore specific support for 32-bit ELF
2 Copyright (C) 1994-2016 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
22 /* This file is based on a preliminary RCE ELF ABI. The
23 information may not match the final RCE ELF ABI. */
30 #include "elf/mcore.h"
33 /* RELA relocs are used here... */
35 /* Function to set whether a module needs the -mrelocatable bit set. */
38 mcore_elf_set_private_flags (bfd
* abfd
, flagword flags
)
40 BFD_ASSERT (! elf_flags_init (abfd
)
41 || elf_elfheader (abfd
)->e_flags
== flags
);
43 elf_elfheader (abfd
)->e_flags
= flags
;
44 elf_flags_init (abfd
) = TRUE
;
48 /* Merge backend specific data from an object file to the output
49 object file when linking. */
52 mcore_elf_merge_private_bfd_data (bfd
*ibfd
, struct bfd_link_info
*info
)
54 bfd
*obfd
= info
->output_bfd
;
58 /* Check if we have the same endianness. */
59 if (! _bfd_generic_verify_endian_match (ibfd
, info
))
62 if ( bfd_get_flavour (ibfd
) != bfd_target_elf_flavour
63 || bfd_get_flavour (obfd
) != bfd_target_elf_flavour
)
66 new_flags
= elf_elfheader (ibfd
)->e_flags
;
67 old_flags
= elf_elfheader (obfd
)->e_flags
;
69 if (! elf_flags_init (obfd
))
71 /* First call, no flags set. */
72 elf_flags_init (obfd
) = TRUE
;
73 elf_elfheader (obfd
)->e_flags
= new_flags
;
75 else if (new_flags
== old_flags
)
76 /* Compatible flags are OK. */
86 /* Don't pretend we can deal with unsupported relocs. */
88 static bfd_reloc_status_type
89 mcore_elf_unsupported_reloc (bfd
* abfd
,
90 arelent
* reloc_entry
,
91 asymbol
* symbol ATTRIBUTE_UNUSED
,
92 void * data ATTRIBUTE_UNUSED
,
93 asection
* input_section ATTRIBUTE_UNUSED
,
94 bfd
* output_bfd ATTRIBUTE_UNUSED
,
95 char ** error_message ATTRIBUTE_UNUSED
)
97 BFD_ASSERT (reloc_entry
->howto
!= (reloc_howto_type
*)0);
99 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
101 reloc_entry
->howto
->name
,
102 reloc_entry
->howto
->type
);
104 return bfd_reloc_notsupported
;
107 static reloc_howto_type
* mcore_elf_howto_table
[(int) R_MCORE_max
];
109 static reloc_howto_type mcore_elf_howto_raw
[] =
111 /* This reloc does nothing. */
112 HOWTO (R_MCORE_NONE
, /* type */
114 3, /* size (0 = byte, 1 = short, 2 = long) */
116 FALSE
, /* pc_relative */
118 complain_overflow_dont
, /* complain_on_overflow */
119 NULL
, /* special_function */
120 "R_MCORE_NONE", /* name */
121 FALSE
, /* partial_inplace */
124 FALSE
), /* pcrel_offset */
126 /* A standard 32 bit relocation. */
127 HOWTO (R_MCORE_ADDR32
, /* type */
129 2, /* size (0 = byte, 1 = short, 2 = long) */
131 FALSE
, /* pc_relative */
133 complain_overflow_bitfield
, /* complain_on_overflow */
134 bfd_elf_generic_reloc
, /* special_function */
135 "ADDR32", /* name *//* For compatibility with coff/pe port. */
136 FALSE
, /* partial_inplace */
138 0xffffffff, /* dst_mask */
139 FALSE
), /* pcrel_offset */
141 /* 8 bits + 2 zero bits; jmpi/jsri/lrw instructions.
142 Should not appear in object files. */
143 HOWTO (R_MCORE_PCRELIMM8BY4
, /* type */
145 1, /* size (0 = byte, 1 = short, 2 = long) */
147 TRUE
, /* pc_relative */
149 complain_overflow_bitfield
, /* complain_on_overflow */
150 mcore_elf_unsupported_reloc
, /* special_function */
151 "R_MCORE_PCRELIMM8BY4",/* name */
152 FALSE
, /* partial_inplace */
155 TRUE
), /* pcrel_offset */
157 /* bsr/bt/bf/br instructions; 11 bits + 1 zero bit
158 Span 2k instructions == 4k bytes.
159 Only useful pieces at the relocated address are the opcode (5 bits) */
160 HOWTO (R_MCORE_PCRELIMM11BY2
,/* type */
162 1, /* size (0 = byte, 1 = short, 2 = long) */
164 TRUE
, /* pc_relative */
166 complain_overflow_signed
, /* complain_on_overflow */
167 bfd_elf_generic_reloc
, /* special_function */
168 "R_MCORE_PCRELIMM11BY2",/* name */
169 FALSE
, /* partial_inplace */
171 0x7ff, /* dst_mask */
172 TRUE
), /* pcrel_offset */
174 /* 4 bits + 1 zero bit; 'loopt' instruction only; unsupported. */
175 HOWTO (R_MCORE_PCRELIMM4BY2
, /* type */
177 1, /* size (0 = byte, 1 = short, 2 = long) */
179 TRUE
, /* pc_relative */
181 complain_overflow_bitfield
, /* complain_on_overflow */
182 mcore_elf_unsupported_reloc
,/* special_function */
183 "R_MCORE_PCRELIMM4BY2",/* name */
184 FALSE
, /* partial_inplace */
187 TRUE
), /* pcrel_offset */
189 /* 32-bit pc-relative. Eventually this will help support PIC code. */
190 HOWTO (R_MCORE_PCREL32
, /* type */
192 2, /* size (0 = byte, 1 = short, 2 = long) */
194 TRUE
, /* pc_relative */
196 complain_overflow_bitfield
, /* complain_on_overflow */
197 bfd_elf_generic_reloc
, /* special_function */
198 "R_MCORE_PCREL32", /* name */
199 FALSE
, /* partial_inplace */
201 0xffffffff, /* dst_mask */
202 TRUE
), /* pcrel_offset */
204 /* Like PCRELIMM11BY2, this relocation indicates that there is a
205 'jsri' at the specified address. There is a separate relocation
206 entry for the literal pool entry that it references, but we
207 might be able to change the jsri to a bsr if the target turns out
208 to be close enough [even though we won't reclaim the literal pool
209 entry, we'll get some runtime efficiency back]. Note that this
210 is a relocation that we are allowed to safely ignore. */
211 HOWTO (R_MCORE_PCRELJSR_IMM11BY2
,/* type */
213 1, /* size (0 = byte, 1 = short, 2 = long) */
215 TRUE
, /* pc_relative */
217 complain_overflow_signed
, /* complain_on_overflow */
218 bfd_elf_generic_reloc
, /* special_function */
219 "R_MCORE_PCRELJSR_IMM11BY2", /* name */
220 FALSE
, /* partial_inplace */
222 0x7ff, /* dst_mask */
223 TRUE
), /* pcrel_offset */
225 /* GNU extension to record C++ vtable hierarchy. */
226 HOWTO (R_MCORE_GNU_VTINHERIT
, /* type */
228 2, /* size (0 = byte, 1 = short, 2 = long) */
230 FALSE
, /* pc_relative */
232 complain_overflow_dont
, /* complain_on_overflow */
233 NULL
, /* special_function */
234 "R_MCORE_GNU_VTINHERIT", /* name */
235 FALSE
, /* partial_inplace */
238 FALSE
), /* pcrel_offset */
240 /* GNU extension to record C++ vtable member usage. */
241 HOWTO (R_MCORE_GNU_VTENTRY
, /* type */
243 2, /* size (0 = byte, 1 = short, 2 = long) */
245 FALSE
, /* pc_relative */
247 complain_overflow_dont
,/* complain_on_overflow */
248 _bfd_elf_rel_vtable_reloc_fn
, /* special_function */
249 "R_MCORE_GNU_VTENTRY", /* name */
250 FALSE
, /* partial_inplace */
253 FALSE
), /* pcrel_offset */
255 HOWTO (R_MCORE_RELATIVE
, /* type */
257 2, /* size (0 = byte, 1 = short, 2 = long) */
259 FALSE
, /* pc_relative */
261 complain_overflow_signed
, /* complain_on_overflow */
262 NULL
, /* special_function */
263 "R_MCORE_RELATIVE", /* name */
264 TRUE
, /* partial_inplace */
265 0xffffffff, /* src_mask */
266 0xffffffff, /* dst_mask */
267 FALSE
) /* pcrel_offset */
271 #define NUM_ELEM(a) (sizeof (a) / sizeof (a)[0])
274 /* Initialize the mcore_elf_howto_table, so that linear accesses can be done. */
276 mcore_elf_howto_init (void)
280 for (i
= NUM_ELEM (mcore_elf_howto_raw
); i
--;)
284 type
= mcore_elf_howto_raw
[i
].type
;
286 BFD_ASSERT (type
< NUM_ELEM (mcore_elf_howto_table
));
288 mcore_elf_howto_table
[type
] = & mcore_elf_howto_raw
[i
];
292 static reloc_howto_type
*
293 mcore_elf_reloc_type_lookup (bfd
* abfd ATTRIBUTE_UNUSED
,
294 bfd_reloc_code_real_type code
)
296 enum elf_mcore_reloc_type mcore_reloc
= R_MCORE_NONE
;
300 case BFD_RELOC_NONE
: mcore_reloc
= R_MCORE_NONE
; break;
301 case BFD_RELOC_32
: mcore_reloc
= R_MCORE_ADDR32
; break;
302 case BFD_RELOC_MCORE_PCREL_IMM8BY4
: mcore_reloc
= R_MCORE_PCRELIMM8BY4
; break;
303 case BFD_RELOC_MCORE_PCREL_IMM11BY2
: mcore_reloc
= R_MCORE_PCRELIMM11BY2
; break;
304 case BFD_RELOC_MCORE_PCREL_IMM4BY2
: mcore_reloc
= R_MCORE_PCRELIMM4BY2
; break;
305 case BFD_RELOC_32_PCREL
: mcore_reloc
= R_MCORE_PCREL32
; break;
306 case BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2
: mcore_reloc
= R_MCORE_PCRELJSR_IMM11BY2
; break;
307 case BFD_RELOC_VTABLE_INHERIT
: mcore_reloc
= R_MCORE_GNU_VTINHERIT
; break;
308 case BFD_RELOC_VTABLE_ENTRY
: mcore_reloc
= R_MCORE_GNU_VTENTRY
; break;
309 case BFD_RELOC_RVA
: mcore_reloc
= R_MCORE_RELATIVE
; break;
314 if (! mcore_elf_howto_table
[R_MCORE_PCRELIMM8BY4
])
315 /* Initialize howto table if needed. */
316 mcore_elf_howto_init ();
318 return mcore_elf_howto_table
[(int) mcore_reloc
];
321 static reloc_howto_type
*
322 mcore_elf_reloc_name_lookup (bfd
*abfd ATTRIBUTE_UNUSED
,
328 i
< sizeof (mcore_elf_howto_raw
) / sizeof (mcore_elf_howto_raw
[0]);
330 if (mcore_elf_howto_raw
[i
].name
!= NULL
331 && strcasecmp (mcore_elf_howto_raw
[i
].name
, r_name
) == 0)
332 return &mcore_elf_howto_raw
[i
];
337 /* Set the howto pointer for a RCE ELF reloc. */
340 mcore_elf_info_to_howto (bfd
* abfd ATTRIBUTE_UNUSED
,
342 Elf_Internal_Rela
* dst
)
346 if (! mcore_elf_howto_table
[R_MCORE_PCRELIMM8BY4
])
347 /* Initialize howto table if needed. */
348 mcore_elf_howto_init ();
350 r_type
= ELF32_R_TYPE (dst
->r_info
);
351 if (r_type
>= R_MCORE_max
)
353 _bfd_error_handler (_("%B: unrecognised MCore reloc number: %d"),
355 bfd_set_error (bfd_error_bad_value
);
356 r_type
= R_MCORE_NONE
;
359 cache_ptr
->howto
= mcore_elf_howto_table
[r_type
];
362 /* The RELOCATE_SECTION function is called by the ELF backend linker
363 to handle the relocations for a section.
365 The relocs are always passed as Rela structures; if the section
366 actually uses Rel structures, the r_addend field will always be
369 This function is responsible for adjust the section contents as
370 necessary, and (if using Rela relocs and generating a
371 relocatable output file) adjusting the reloc addend as
374 This function does not have to worry about setting the reloc
375 address or the reloc symbol index.
377 LOCAL_SYMS is a pointer to the swapped in local symbols.
379 LOCAL_SECTIONS is an array giving the section in the input file
380 corresponding to the st_shndx field of each local symbol.
382 The global hash table entry for the global symbols can be found
383 via elf_sym_hashes (input_bfd).
385 When generating relocatable output, this function must handle
386 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
387 going to be the section symbol corresponding to the output
388 section, which means that the addend must be adjusted
392 mcore_elf_relocate_section (bfd
* output_bfd
,
393 struct bfd_link_info
* info
,
395 asection
* input_section
,
397 Elf_Internal_Rela
* relocs
,
398 Elf_Internal_Sym
* local_syms
,
399 asection
** local_sections
)
401 Elf_Internal_Shdr
* symtab_hdr
= & elf_tdata (input_bfd
)->symtab_hdr
;
402 struct elf_link_hash_entry
** sym_hashes
= elf_sym_hashes (input_bfd
);
403 Elf_Internal_Rela
* rel
= relocs
;
404 Elf_Internal_Rela
* relend
= relocs
+ input_section
->reloc_count
;
405 bfd_boolean ret
= TRUE
;
409 ("mcore_elf_relocate_section called for %B section %A, %ld relocations%s",
412 (long) input_section
->reloc_count
,
413 (bfd_link_relocatable (info
)) ? " (relocatable)" : "");
416 if (! mcore_elf_howto_table
[R_MCORE_PCRELIMM8BY4
]) /* Initialize howto table if needed */
417 mcore_elf_howto_init ();
419 for (; rel
< relend
; rel
++)
421 enum elf_mcore_reloc_type r_type
= (enum elf_mcore_reloc_type
) ELF32_R_TYPE (rel
->r_info
);
422 bfd_vma offset
= rel
->r_offset
;
423 bfd_vma addend
= rel
->r_addend
;
424 bfd_reloc_status_type r
= bfd_reloc_other
;
425 asection
* sec
= NULL
;
426 reloc_howto_type
* howto
;
428 Elf_Internal_Sym
* sym
= NULL
;
429 unsigned long r_symndx
;
430 struct elf_link_hash_entry
* h
= NULL
;
431 unsigned short oldinst
= 0;
433 /* Unknown relocation handling. */
434 if ((unsigned) r_type
>= (unsigned) R_MCORE_max
435 || ! mcore_elf_howto_table
[(int)r_type
])
437 _bfd_error_handler (_("%B: Unknown relocation type %d\n"),
438 input_bfd
, (int) r_type
);
440 bfd_set_error (bfd_error_bad_value
);
445 howto
= mcore_elf_howto_table
[(int) r_type
];
446 r_symndx
= ELF32_R_SYM (rel
->r_info
);
448 /* Complain about known relocation that are not yet supported. */
449 if (howto
->special_function
== mcore_elf_unsupported_reloc
)
451 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
456 bfd_set_error (bfd_error_bad_value
);
461 if (r_symndx
< symtab_hdr
->sh_info
)
463 sym
= local_syms
+ r_symndx
;
464 sec
= local_sections
[r_symndx
];
465 relocation
= _bfd_elf_rela_local_sym (output_bfd
, sym
, &sec
, rel
);
466 addend
= rel
->r_addend
;
470 bfd_boolean unresolved_reloc
, warned
, ignored
;
472 RELOC_FOR_GLOBAL_SYMBOL (info
, input_bfd
, input_section
, rel
,
473 r_symndx
, symtab_hdr
, sym_hashes
,
475 unresolved_reloc
, warned
, ignored
);
478 if (sec
!= NULL
&& discarded_section (sec
))
479 RELOC_AGAINST_DISCARDED_SECTION (info
, input_bfd
, input_section
,
480 rel
, 1, relend
, howto
, 0, contents
);
482 if (bfd_link_relocatable (info
))
490 case R_MCORE_PCRELJSR_IMM11BY2
:
491 oldinst
= bfd_get_16 (input_bfd
, contents
+ offset
);
492 #define MCORE_INST_BSR 0xF800
493 bfd_put_16 (input_bfd
, (bfd_vma
) MCORE_INST_BSR
, contents
+ offset
);
498 fprintf (stderr
, "\ttype = %s (%d), symbol index = %ld, offset = %ld, addend = %ld\n",
499 howto
->name
, r_type
, r_symndx
, (long) offset
, (long) addend
);
502 r
= _bfd_final_link_relocate
503 (howto
, input_bfd
, input_section
, contents
, offset
, relocation
, addend
);
505 if (r
!= bfd_reloc_ok
&& r_type
== R_MCORE_PCRELJSR_IMM11BY2
)
507 /* Wasn't ok, back it out and give up. */
508 bfd_put_16 (input_bfd
, (bfd_vma
) oldinst
, contents
+ offset
);
512 if (r
!= bfd_reloc_ok
)
521 case bfd_reloc_overflow
:
529 name
= bfd_elf_string_from_elf_section
530 (input_bfd
, symtab_hdr
->sh_link
, sym
->st_name
);
536 name
= bfd_section_name (input_bfd
, sec
);
539 (*info
->callbacks
->reloc_overflow
)
540 (info
, (h
? &h
->root
: NULL
), name
, howto
->name
,
541 (bfd_vma
) 0, input_bfd
, input_section
, offset
);
549 fprintf (stderr
, "\n");
555 /* Return the section that should be marked against GC for a given
559 mcore_elf_gc_mark_hook (asection
*sec
,
560 struct bfd_link_info
*info
,
561 Elf_Internal_Rela
*rel
,
562 struct elf_link_hash_entry
*h
,
563 Elf_Internal_Sym
*sym
)
566 switch (ELF32_R_TYPE (rel
->r_info
))
568 case R_MCORE_GNU_VTINHERIT
:
569 case R_MCORE_GNU_VTENTRY
:
573 return _bfd_elf_gc_mark_hook (sec
, info
, rel
, h
, sym
);
576 /* Update the got entry reference counts for the section being removed. */
579 mcore_elf_gc_sweep_hook (bfd
* abfd ATTRIBUTE_UNUSED
,
580 struct bfd_link_info
* info ATTRIBUTE_UNUSED
,
581 asection
* sec ATTRIBUTE_UNUSED
,
582 const Elf_Internal_Rela
* relocs ATTRIBUTE_UNUSED
)
587 /* Look through the relocs for a section during the first phase.
588 Since we don't do .gots or .plts, we just need to consider the
589 virtual table relocs for gc. */
592 mcore_elf_check_relocs (bfd
* abfd
,
593 struct bfd_link_info
* info
,
595 const Elf_Internal_Rela
* relocs
)
597 Elf_Internal_Shdr
* symtab_hdr
;
598 struct elf_link_hash_entry
** sym_hashes
;
599 const Elf_Internal_Rela
* rel
;
600 const Elf_Internal_Rela
* rel_end
;
602 if (bfd_link_relocatable (info
))
605 symtab_hdr
= & elf_tdata (abfd
)->symtab_hdr
;
606 sym_hashes
= elf_sym_hashes (abfd
);
608 rel_end
= relocs
+ sec
->reloc_count
;
610 for (rel
= relocs
; rel
< rel_end
; rel
++)
612 struct elf_link_hash_entry
* h
;
613 unsigned long r_symndx
;
615 r_symndx
= ELF32_R_SYM (rel
->r_info
);
617 if (r_symndx
< symtab_hdr
->sh_info
)
621 h
= sym_hashes
[r_symndx
- symtab_hdr
->sh_info
];
622 while (h
->root
.type
== bfd_link_hash_indirect
623 || h
->root
.type
== bfd_link_hash_warning
)
624 h
= (struct elf_link_hash_entry
*) h
->root
.u
.i
.link
;
626 /* PR15323, ref flags aren't set for references in the same
628 h
->root
.non_ir_ref
= 1;
631 switch (ELF32_R_TYPE (rel
->r_info
))
633 /* This relocation describes the C++ object vtable hierarchy.
634 Reconstruct it for later use during GC. */
635 case R_MCORE_GNU_VTINHERIT
:
636 if (!bfd_elf_gc_record_vtinherit (abfd
, sec
, h
, rel
->r_offset
))
640 /* This relocation describes which C++ vtable entries are actually
641 used. Record for later use during GC. */
642 case R_MCORE_GNU_VTENTRY
:
643 BFD_ASSERT (h
!= NULL
);
645 && !bfd_elf_gc_record_vtentry (abfd
, sec
, h
, rel
->r_addend
))
654 static const struct bfd_elf_special_section mcore_elf_special_sections
[]=
656 { STRING_COMMA_LEN (".ctors"), -2, SHT_PROGBITS
, SHF_ALLOC
+ SHF_WRITE
},
657 { STRING_COMMA_LEN (".dtors"), -2, SHT_PROGBITS
, SHF_ALLOC
+ SHF_WRITE
},
661 #define TARGET_BIG_SYM mcore_elf32_be_vec
662 #define TARGET_BIG_NAME "elf32-mcore-big"
663 #define TARGET_LITTLE_SYM mcore_elf32_le_vec
664 #define TARGET_LITTLE_NAME "elf32-mcore-little"
666 #define ELF_ARCH bfd_arch_mcore
667 #define ELF_MACHINE_CODE EM_MCORE
668 #define ELF_MAXPAGESIZE 0x1000 /* 4k, if we ever have 'em */
669 #define elf_info_to_howto mcore_elf_info_to_howto
670 #define elf_info_to_howto_rel NULL
672 #define bfd_elf32_bfd_merge_private_bfd_data mcore_elf_merge_private_bfd_data
673 #define bfd_elf32_bfd_set_private_flags mcore_elf_set_private_flags
674 #define bfd_elf32_bfd_reloc_type_lookup mcore_elf_reloc_type_lookup
675 #define bfd_elf32_bfd_reloc_name_lookup mcore_elf_reloc_name_lookup
676 #define elf_backend_relocate_section mcore_elf_relocate_section
677 #define elf_backend_gc_mark_hook mcore_elf_gc_mark_hook
678 #define elf_backend_gc_sweep_hook mcore_elf_gc_sweep_hook
679 #define elf_backend_check_relocs mcore_elf_check_relocs
680 #define elf_backend_special_sections mcore_elf_special_sections
682 #define elf_backend_can_gc_sections 1
683 #define elf_backend_rela_normal 1
685 #include "elf32-target.h"