1 /* Motorola MCore specific support for 32-bit ELF
2 Copyright 1994, 1995, 1999, 2000, 2001, 2002, 2003, 2004
3 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21 /* This file is based on a preliminary RCE ELF ABI. The
22 information may not match the final RCE ELF ABI. */
29 #include "elf/mcore.h"
32 /* RELA relocs are used here... */
34 static void mcore_elf_howto_init
36 static reloc_howto_type * mcore_elf_reloc_type_lookup
37 PARAMS ((bfd *, bfd_reloc_code_real_type));
38 static void mcore_elf_info_to_howto
39 PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));
40 static bfd_boolean mcore_elf_set_private_flags
41 PARAMS ((bfd *, flagword));
42 static bfd_boolean mcore_elf_merge_private_bfd_data
43 PARAMS ((bfd *, bfd *));
44 static bfd_reloc_status_type mcore_elf_unsupported_reloc
45 PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
46 static bfd_boolean mcore_elf_relocate_section
47 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
48 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
49 static asection * mcore_elf_gc_mark_hook
50 PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *,
51 struct elf_link_hash_entry *, Elf_Internal_Sym *));
52 static bfd_boolean mcore_elf_gc_sweep_hook
53 PARAMS ((bfd *, struct bfd_link_info *, asection *,
54 const Elf_Internal_Rela *));
55 static bfd_boolean mcore_elf_check_relocs
56 PARAMS ((bfd *, struct bfd_link_info *, asection *,
57 const Elf_Internal_Rela *));
59 static reloc_howto_type * mcore_elf_howto_table [(int) R_MCORE_max];
61 static reloc_howto_type mcore_elf_howto_raw[] =
63 /* This reloc does nothing. */
64 HOWTO (R_MCORE_NONE, /* type */
66 2, /* size (0 = byte, 1 = short, 2 = long) */
68 FALSE, /* pc_relative */
70 complain_overflow_bitfield, /* complain_on_overflow */
71 NULL, /* special_function */
72 "R_MCORE_NONE", /* name */
73 FALSE, /* partial_inplace */
76 FALSE), /* pcrel_offset */
78 /* A standard 32 bit relocation. */
79 HOWTO (R_MCORE_ADDR32, /* type */
81 2, /* size (0 = byte, 1 = short, 2 = long) */
83 FALSE, /* pc_relative */
85 complain_overflow_bitfield, /* complain_on_overflow */
86 bfd_elf_generic_reloc, /* special_function */
87 "ADDR32", /* name *//* For compatibility with coff/pe port. */
88 FALSE, /* partial_inplace */
90 0xffffffff, /* dst_mask */
91 FALSE), /* pcrel_offset */
93 /* 8 bits + 2 zero bits; jmpi/jsri/lrw instructions.
94 Should not appear in object files. */
95 HOWTO (R_MCORE_PCRELIMM8BY4, /* type */
97 1, /* size (0 = byte, 1 = short, 2 = long) */
99 TRUE, /* pc_relative */
101 complain_overflow_bitfield, /* complain_on_overflow */
102 mcore_elf_unsupported_reloc, /* special_function */
103 "R_MCORE_PCRELIMM8BY4",/* name */
104 FALSE, /* partial_inplace */
107 TRUE), /* pcrel_offset */
109 /* bsr/bt/bf/br instructions; 11 bits + 1 zero bit
110 Span 2k instructions == 4k bytes.
111 Only useful pieces at the relocated address are the opcode (5 bits) */
112 HOWTO (R_MCORE_PCRELIMM11BY2,/* type */
114 1, /* size (0 = byte, 1 = short, 2 = long) */
116 TRUE, /* pc_relative */
118 complain_overflow_signed, /* complain_on_overflow */
119 bfd_elf_generic_reloc, /* special_function */
120 "R_MCORE_PCRELIMM11BY2",/* name */
121 FALSE, /* partial_inplace */
123 0x7ff, /* dst_mask */
124 TRUE), /* pcrel_offset */
126 /* 4 bits + 1 zero bit; 'loopt' instruction only; unsupported. */
127 HOWTO (R_MCORE_PCRELIMM4BY2, /* type */
129 1, /* size (0 = byte, 1 = short, 2 = long) */
131 TRUE, /* pc_relative */
133 complain_overflow_bitfield, /* complain_on_overflow */
134 mcore_elf_unsupported_reloc,/* special_function */
135 "R_MCORE_PCRELIMM4BY2",/* name */
136 FALSE, /* partial_inplace */
139 TRUE), /* pcrel_offset */
141 /* 32-bit pc-relative. Eventually this will help support PIC code. */
142 HOWTO (R_MCORE_PCREL32, /* type */
144 2, /* size (0 = byte, 1 = short, 2 = long) */
146 TRUE, /* pc_relative */
148 complain_overflow_bitfield, /* complain_on_overflow */
149 bfd_elf_generic_reloc, /* special_function */
150 "R_MCORE_PCREL32", /* name */
151 FALSE, /* partial_inplace */
153 0xffffffff, /* dst_mask */
154 TRUE), /* pcrel_offset */
156 /* Like PCRELIMM11BY2, this relocation indicates that there is a
157 'jsri' at the specified address. There is a separate relocation
158 entry for the literal pool entry that it references, but we
159 might be able to change the jsri to a bsr if the target turns out
160 to be close enough [even though we won't reclaim the literal pool
161 entry, we'll get some runtime efficiency back]. Note that this
162 is a relocation that we are allowed to safely ignore. */
163 HOWTO (R_MCORE_PCRELJSR_IMM11BY2,/* type */
165 1, /* size (0 = byte, 1 = short, 2 = long) */
167 TRUE, /* pc_relative */
169 complain_overflow_signed, /* complain_on_overflow */
170 bfd_elf_generic_reloc, /* special_function */
171 "R_MCORE_PCRELJSR_IMM11BY2", /* name */
172 FALSE, /* partial_inplace */
174 0x7ff, /* dst_mask */
175 TRUE), /* pcrel_offset */
177 /* GNU extension to record C++ vtable hierarchy */
178 HOWTO (R_MCORE_GNU_VTINHERIT, /* type */
180 2, /* size (0 = byte, 1 = short, 2 = long) */
182 FALSE, /* pc_relative */
184 complain_overflow_dont, /* complain_on_overflow */
185 NULL, /* special_function */
186 "R_MCORE_GNU_VTINHERIT", /* name */
187 FALSE, /* partial_inplace */
190 FALSE), /* pcrel_offset */
192 /* GNU extension to record C++ vtable member usage */
193 HOWTO (R_MCORE_GNU_VTENTRY, /* type */
195 2, /* size (0 = byte, 1 = short, 2 = long) */
197 FALSE, /* pc_relative */
199 complain_overflow_dont,/* complain_on_overflow */
200 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
201 "R_MCORE_GNU_VTENTRY", /* name */
202 FALSE, /* partial_inplace */
205 FALSE), /* pcrel_offset */
207 HOWTO (R_MCORE_RELATIVE, /* type */
209 2, /* size (0 = byte, 1 = short, 2 = long) */
211 FALSE, /* pc_relative */
213 complain_overflow_signed, /* complain_on_overflow */
214 NULL, /* special_function */
215 "R_MCORE_RELATIVE", /* name */
216 TRUE, /* partial_inplace */
217 0xffffffff, /* src_mask */
218 0xffffffff, /* dst_mask */
219 FALSE) /* pcrel_offset */
223 #define NUM_ELEM(a) (sizeof (a) / sizeof (a)[0])
226 /* Initialize the mcore_elf_howto_table, so that linear accesses can be done. */
228 mcore_elf_howto_init ()
232 for (i = NUM_ELEM (mcore_elf_howto_raw); i--;)
236 type = mcore_elf_howto_raw[i].type;
238 BFD_ASSERT (type < NUM_ELEM (mcore_elf_howto_table));
240 mcore_elf_howto_table [type] = & mcore_elf_howto_raw [i];
244 static reloc_howto_type *
245 mcore_elf_reloc_type_lookup (abfd, code)
246 bfd * abfd ATTRIBUTE_UNUSED;
247 bfd_reloc_code_real_type code;
249 enum elf_mcore_reloc_type mcore_reloc = R_MCORE_NONE;
253 case BFD_RELOC_NONE: mcore_reloc = R_MCORE_NONE; break;
254 case BFD_RELOC_32: mcore_reloc = R_MCORE_ADDR32; break;
255 case BFD_RELOC_MCORE_PCREL_IMM8BY4: mcore_reloc = R_MCORE_PCRELIMM8BY4; break;
256 case BFD_RELOC_MCORE_PCREL_IMM11BY2: mcore_reloc = R_MCORE_PCRELIMM11BY2; break;
257 case BFD_RELOC_MCORE_PCREL_IMM4BY2: mcore_reloc = R_MCORE_PCRELIMM4BY2; break;
258 case BFD_RELOC_32_PCREL: mcore_reloc = R_MCORE_PCREL32; break;
259 case BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2: mcore_reloc = R_MCORE_PCRELJSR_IMM11BY2; break;
260 case BFD_RELOC_VTABLE_INHERIT: mcore_reloc = R_MCORE_GNU_VTINHERIT; break;
261 case BFD_RELOC_VTABLE_ENTRY: mcore_reloc = R_MCORE_GNU_VTENTRY; break;
262 case BFD_RELOC_RVA: mcore_reloc = R_MCORE_RELATIVE; break;
264 return (reloc_howto_type *)NULL;
267 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4]) /* Initialize howto table if needed */
268 mcore_elf_howto_init ();
270 return mcore_elf_howto_table [(int) mcore_reloc];
273 /* Set the howto pointer for a RCE ELF reloc. */
275 mcore_elf_info_to_howto (abfd, cache_ptr, dst)
276 bfd * abfd ATTRIBUTE_UNUSED;
278 Elf_Internal_Rela * dst;
280 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4]) /* Initialize howto table if needed */
281 mcore_elf_howto_init ();
283 BFD_ASSERT (ELF32_R_TYPE (dst->r_info) < (unsigned int) R_MCORE_max);
285 cache_ptr->howto = mcore_elf_howto_table [ELF32_R_TYPE (dst->r_info)];
288 /* Function to set whether a module needs the -mrelocatable bit set. */
290 mcore_elf_set_private_flags (abfd, flags)
294 BFD_ASSERT (! elf_flags_init (abfd)
295 || elf_elfheader (abfd)->e_flags == flags);
297 elf_elfheader (abfd)->e_flags = flags;
298 elf_flags_init (abfd) = TRUE;
302 /* Merge backend specific data from an object file to the output
303 object file when linking. */
305 mcore_elf_merge_private_bfd_data (ibfd, obfd)
312 /* Check if we have the same endianess */
313 if (! _bfd_generic_verify_endian_match (ibfd, obfd))
316 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
317 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
320 new_flags = elf_elfheader (ibfd)->e_flags;
321 old_flags = elf_elfheader (obfd)->e_flags;
323 if (! elf_flags_init (obfd)) /* First call, no flags set */
325 elf_flags_init (obfd) = TRUE;
326 elf_elfheader (obfd)->e_flags = new_flags;
328 else if (new_flags == old_flags) /* Compatible flags are ok */
338 /* Don't pretend we can deal with unsupported relocs. */
340 static bfd_reloc_status_type
341 mcore_elf_unsupported_reloc (abfd, reloc_entry, symbol, data, input_section,
342 output_bfd, error_message)
344 arelent * reloc_entry;
345 asymbol * symbol ATTRIBUTE_UNUSED;
346 PTR data ATTRIBUTE_UNUSED;
347 asection * input_section ATTRIBUTE_UNUSED;
348 bfd * output_bfd ATTRIBUTE_UNUSED;
349 char ** error_message ATTRIBUTE_UNUSED;
351 BFD_ASSERT (reloc_entry->howto != (reloc_howto_type *)0);
353 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
355 reloc_entry->howto->name,
356 reloc_entry->howto->type);
358 return bfd_reloc_notsupported;
361 /* The RELOCATE_SECTION function is called by the ELF backend linker
362 to handle the relocations for a section.
364 The relocs are always passed as Rela structures; if the section
365 actually uses Rel structures, the r_addend field will always be
368 This function is responsible for adjust the section contents as
369 necessary, and (if using Rela relocs and generating a
370 relocatable output file) adjusting the reloc addend as
373 This function does not have to worry about setting the reloc
374 address or the reloc symbol index.
376 LOCAL_SYMS is a pointer to the swapped in local symbols.
378 LOCAL_SECTIONS is an array giving the section in the input file
379 corresponding to the st_shndx field of each local symbol.
381 The global hash table entry for the global symbols can be found
382 via elf_sym_hashes (input_bfd).
384 When generating relocatable output, this function must handle
385 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
386 going to be the section symbol corresponding to the output
387 section, which means that the addend must be adjusted
391 mcore_elf_relocate_section (output_bfd, info, input_bfd, input_section,
392 contents, relocs, local_syms, local_sections)
394 struct bfd_link_info * info;
396 asection * input_section;
398 Elf_Internal_Rela * relocs;
399 Elf_Internal_Sym * local_syms;
400 asection ** local_sections;
402 Elf_Internal_Shdr * symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
403 struct elf_link_hash_entry ** sym_hashes = elf_sym_hashes (input_bfd);
404 Elf_Internal_Rela * rel = relocs;
405 Elf_Internal_Rela * relend = relocs + input_section->reloc_count;
406 bfd_boolean ret = TRUE;
410 ("mcore_elf_relocate_section called for %B section %A, %ld relocations%s",
413 (long) input_section->reloc_count,
414 (info->relocatable) ? " (relocatable)" : "");
417 if (info->relocatable)
420 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4]) /* Initialize howto table if needed */
421 mcore_elf_howto_init ();
423 for (; rel < relend; rel++)
425 enum elf_mcore_reloc_type r_type = (enum elf_mcore_reloc_type) ELF32_R_TYPE (rel->r_info);
426 bfd_vma offset = rel->r_offset;
427 bfd_vma addend = rel->r_addend;
428 bfd_reloc_status_type r = bfd_reloc_other;
429 asection * sec = (asection *) 0;
430 reloc_howto_type * howto;
432 Elf_Internal_Sym * sym = (Elf_Internal_Sym *) 0;
433 unsigned long r_symndx;
434 struct elf_link_hash_entry * h = (struct elf_link_hash_entry *) 0;
435 unsigned short oldinst = 0;
437 /* Unknown relocation handling */
438 if ((unsigned) r_type >= (unsigned) R_MCORE_max
439 || ! mcore_elf_howto_table [(int)r_type])
441 _bfd_error_handler (_("%B: Unknown relocation type %d\n"),
442 input_bfd, (int) r_type);
444 bfd_set_error (bfd_error_bad_value);
449 howto = mcore_elf_howto_table [(int) r_type];
450 r_symndx = ELF32_R_SYM (rel->r_info);
452 /* Complain about known relocation that are not yet supported. */
453 if (howto->special_function == mcore_elf_unsupported_reloc)
455 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
460 bfd_set_error (bfd_error_bad_value);
465 if (r_symndx < symtab_hdr->sh_info)
467 sym = local_syms + r_symndx;
468 sec = local_sections [r_symndx];
469 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
470 addend = rel->r_addend;
474 bfd_boolean unresolved_reloc, warned;
476 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
477 r_symndx, symtab_hdr, sym_hashes,
479 unresolved_reloc, warned);
487 case R_MCORE_PCRELJSR_IMM11BY2:
488 oldinst = bfd_get_16 (input_bfd, contents + offset);
489 #define MCORE_INST_BSR 0xF800
490 bfd_put_16 (input_bfd, (bfd_vma) MCORE_INST_BSR, contents + offset);
495 fprintf (stderr, "\ttype = %s (%d), symbol index = %ld, offset = %ld, addend = %ld\n",
496 howto->name, r_type, r_symndx, (long) offset, (long) addend);
499 r = _bfd_final_link_relocate
500 (howto, input_bfd, input_section, contents, offset, relocation, addend);
502 if (r != bfd_reloc_ok && r_type == R_MCORE_PCRELJSR_IMM11BY2)
504 /* Wasn't ok, back it out and give up. */
505 bfd_put_16 (input_bfd, (bfd_vma) oldinst, contents + offset);
509 if (r != bfd_reloc_ok)
518 case bfd_reloc_overflow:
526 name = bfd_elf_string_from_elf_section
527 (input_bfd, symtab_hdr->sh_link, sym->st_name);
533 name = bfd_section_name (input_bfd, sec);
536 (*info->callbacks->reloc_overflow)
537 (info, (h ? &h->root : NULL), name, howto->name,
538 (bfd_vma) 0, input_bfd, input_section, offset);
546 fprintf (stderr, "\n");
552 /* Return the section that should be marked against GC for a given
556 mcore_elf_gc_mark_hook (sec, info, rel, h, sym)
558 struct bfd_link_info * info ATTRIBUTE_UNUSED;
559 Elf_Internal_Rela * rel;
560 struct elf_link_hash_entry * h;
561 Elf_Internal_Sym * sym;
565 switch (ELF32_R_TYPE (rel->r_info))
567 case R_MCORE_GNU_VTINHERIT:
568 case R_MCORE_GNU_VTENTRY:
572 switch (h->root.type)
574 case bfd_link_hash_defined:
575 case bfd_link_hash_defweak:
576 return h->root.u.def.section;
578 case bfd_link_hash_common:
579 return h->root.u.c.p->section;
587 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
592 /* Update the got entry reference counts for the section being removed. */
595 mcore_elf_gc_sweep_hook (abfd, info, sec, relocs)
596 bfd * abfd ATTRIBUTE_UNUSED;
597 struct bfd_link_info * info ATTRIBUTE_UNUSED;
598 asection * sec ATTRIBUTE_UNUSED;
599 const Elf_Internal_Rela * relocs ATTRIBUTE_UNUSED;
604 /* Look through the relocs for a section during the first phase.
605 Since we don't do .gots or .plts, we just need to consider the
606 virtual table relocs for gc. */
609 mcore_elf_check_relocs (abfd, info, sec, relocs)
611 struct bfd_link_info * info;
613 const Elf_Internal_Rela * relocs;
615 Elf_Internal_Shdr * symtab_hdr;
616 struct elf_link_hash_entry ** sym_hashes;
617 struct elf_link_hash_entry ** sym_hashes_end;
618 const Elf_Internal_Rela * rel;
619 const Elf_Internal_Rela * rel_end;
621 if (info->relocatable)
624 symtab_hdr = & elf_tdata (abfd)->symtab_hdr;
625 sym_hashes = elf_sym_hashes (abfd);
626 sym_hashes_end = sym_hashes + symtab_hdr->sh_size / sizeof (Elf32_External_Sym);
627 if (!elf_bad_symtab (abfd))
628 sym_hashes_end -= symtab_hdr->sh_info;
630 rel_end = relocs + sec->reloc_count;
632 for (rel = relocs; rel < rel_end; rel++)
634 struct elf_link_hash_entry * h;
635 unsigned long r_symndx;
637 r_symndx = ELF32_R_SYM (rel->r_info);
639 if (r_symndx < symtab_hdr->sh_info)
642 h = sym_hashes [r_symndx - symtab_hdr->sh_info];
644 switch (ELF32_R_TYPE (rel->r_info))
646 /* This relocation describes the C++ object vtable hierarchy.
647 Reconstruct it for later use during GC. */
648 case R_MCORE_GNU_VTINHERIT:
649 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
653 /* This relocation describes which C++ vtable entries are actually
654 used. Record for later use during GC. */
655 case R_MCORE_GNU_VTENTRY:
656 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
665 static struct bfd_elf_special_section const
666 mcore_special_sections_c [] =
668 { ".ctors", 6, -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
672 static struct bfd_elf_special_section const
673 mcore_special_sections_d[]=
675 { ".dtors", 6, -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
679 static struct bfd_elf_special_section const *
680 mcore_elf_special_sections[27]=
684 mcore_special_sections_c, /* 'c' */
685 mcore_special_sections_d, /* 'd' */
711 #define TARGET_BIG_SYM bfd_elf32_mcore_big_vec
712 #define TARGET_BIG_NAME "elf32-mcore-big"
713 #define TARGET_LITTLE_SYM bfd_elf32_mcore_little_vec
714 #define TARGET_LITTLE_NAME "elf32-mcore-little"
716 #define ELF_ARCH bfd_arch_mcore
717 #define ELF_MACHINE_CODE EM_MCORE
718 #define ELF_MAXPAGESIZE 0x1000 /* 4k, if we ever have 'em */
719 #define elf_info_to_howto mcore_elf_info_to_howto
720 #define elf_info_to_howto_rel NULL
722 #define bfd_elf32_bfd_merge_private_bfd_data mcore_elf_merge_private_bfd_data
723 #define bfd_elf32_bfd_set_private_flags mcore_elf_set_private_flags
724 #define bfd_elf32_bfd_reloc_type_lookup mcore_elf_reloc_type_lookup
725 #define elf_backend_relocate_section mcore_elf_relocate_section
726 #define elf_backend_gc_mark_hook mcore_elf_gc_mark_hook
727 #define elf_backend_gc_sweep_hook mcore_elf_gc_sweep_hook
728 #define elf_backend_check_relocs mcore_elf_check_relocs
729 #define elf_backend_special_sections mcore_elf_special_sections
731 #define elf_backend_can_gc_sections 1
732 #define elf_backend_rela_normal 1
734 #include "elf32-target.h"