1 /* Motorola MCore specific support for 32-bit ELF
2 Copyright (C) 1994-2015 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, bfd * obfd)
57 /* Check if we have the same endianness. */
58 if (! _bfd_generic_verify_endian_match (ibfd, obfd))
61 if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
62 || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
65 new_flags = elf_elfheader (ibfd)->e_flags;
66 old_flags = elf_elfheader (obfd)->e_flags;
68 if (! elf_flags_init (obfd))
70 /* First call, no flags set. */
71 elf_flags_init (obfd) = TRUE;
72 elf_elfheader (obfd)->e_flags = new_flags;
74 else if (new_flags == old_flags)
75 /* Compatible flags are OK. */
85 /* Don't pretend we can deal with unsupported relocs. */
87 static bfd_reloc_status_type
88 mcore_elf_unsupported_reloc (bfd * abfd,
89 arelent * reloc_entry,
90 asymbol * symbol ATTRIBUTE_UNUSED,
91 void * data ATTRIBUTE_UNUSED,
92 asection * input_section ATTRIBUTE_UNUSED,
93 bfd * output_bfd ATTRIBUTE_UNUSED,
94 char ** error_message ATTRIBUTE_UNUSED)
96 BFD_ASSERT (reloc_entry->howto != (reloc_howto_type *)0);
98 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
100 reloc_entry->howto->name,
101 reloc_entry->howto->type);
103 return bfd_reloc_notsupported;
106 static reloc_howto_type * mcore_elf_howto_table [(int) R_MCORE_max];
108 static reloc_howto_type mcore_elf_howto_raw[] =
110 /* This reloc does nothing. */
111 HOWTO (R_MCORE_NONE, /* type */
113 3, /* size (0 = byte, 1 = short, 2 = long) */
115 FALSE, /* pc_relative */
117 complain_overflow_dont, /* complain_on_overflow */
118 NULL, /* special_function */
119 "R_MCORE_NONE", /* name */
120 FALSE, /* partial_inplace */
123 FALSE), /* pcrel_offset */
125 /* A standard 32 bit relocation. */
126 HOWTO (R_MCORE_ADDR32, /* type */
128 2, /* size (0 = byte, 1 = short, 2 = long) */
130 FALSE, /* pc_relative */
132 complain_overflow_bitfield, /* complain_on_overflow */
133 bfd_elf_generic_reloc, /* special_function */
134 "ADDR32", /* name *//* For compatibility with coff/pe port. */
135 FALSE, /* partial_inplace */
137 0xffffffff, /* dst_mask */
138 FALSE), /* pcrel_offset */
140 /* 8 bits + 2 zero bits; jmpi/jsri/lrw instructions.
141 Should not appear in object files. */
142 HOWTO (R_MCORE_PCRELIMM8BY4, /* type */
144 1, /* size (0 = byte, 1 = short, 2 = long) */
146 TRUE, /* pc_relative */
148 complain_overflow_bitfield, /* complain_on_overflow */
149 mcore_elf_unsupported_reloc, /* special_function */
150 "R_MCORE_PCRELIMM8BY4",/* name */
151 FALSE, /* partial_inplace */
154 TRUE), /* pcrel_offset */
156 /* bsr/bt/bf/br instructions; 11 bits + 1 zero bit
157 Span 2k instructions == 4k bytes.
158 Only useful pieces at the relocated address are the opcode (5 bits) */
159 HOWTO (R_MCORE_PCRELIMM11BY2,/* type */
161 1, /* size (0 = byte, 1 = short, 2 = long) */
163 TRUE, /* pc_relative */
165 complain_overflow_signed, /* complain_on_overflow */
166 bfd_elf_generic_reloc, /* special_function */
167 "R_MCORE_PCRELIMM11BY2",/* name */
168 FALSE, /* partial_inplace */
170 0x7ff, /* dst_mask */
171 TRUE), /* pcrel_offset */
173 /* 4 bits + 1 zero bit; 'loopt' instruction only; unsupported. */
174 HOWTO (R_MCORE_PCRELIMM4BY2, /* type */
176 1, /* size (0 = byte, 1 = short, 2 = long) */
178 TRUE, /* pc_relative */
180 complain_overflow_bitfield, /* complain_on_overflow */
181 mcore_elf_unsupported_reloc,/* special_function */
182 "R_MCORE_PCRELIMM4BY2",/* name */
183 FALSE, /* partial_inplace */
186 TRUE), /* pcrel_offset */
188 /* 32-bit pc-relative. Eventually this will help support PIC code. */
189 HOWTO (R_MCORE_PCREL32, /* type */
191 2, /* size (0 = byte, 1 = short, 2 = long) */
193 TRUE, /* pc_relative */
195 complain_overflow_bitfield, /* complain_on_overflow */
196 bfd_elf_generic_reloc, /* special_function */
197 "R_MCORE_PCREL32", /* name */
198 FALSE, /* partial_inplace */
200 0xffffffff, /* dst_mask */
201 TRUE), /* pcrel_offset */
203 /* Like PCRELIMM11BY2, this relocation indicates that there is a
204 'jsri' at the specified address. There is a separate relocation
205 entry for the literal pool entry that it references, but we
206 might be able to change the jsri to a bsr if the target turns out
207 to be close enough [even though we won't reclaim the literal pool
208 entry, we'll get some runtime efficiency back]. Note that this
209 is a relocation that we are allowed to safely ignore. */
210 HOWTO (R_MCORE_PCRELJSR_IMM11BY2,/* type */
212 1, /* size (0 = byte, 1 = short, 2 = long) */
214 TRUE, /* pc_relative */
216 complain_overflow_signed, /* complain_on_overflow */
217 bfd_elf_generic_reloc, /* special_function */
218 "R_MCORE_PCRELJSR_IMM11BY2", /* name */
219 FALSE, /* partial_inplace */
221 0x7ff, /* dst_mask */
222 TRUE), /* pcrel_offset */
224 /* GNU extension to record C++ vtable hierarchy. */
225 HOWTO (R_MCORE_GNU_VTINHERIT, /* type */
227 2, /* size (0 = byte, 1 = short, 2 = long) */
229 FALSE, /* pc_relative */
231 complain_overflow_dont, /* complain_on_overflow */
232 NULL, /* special_function */
233 "R_MCORE_GNU_VTINHERIT", /* name */
234 FALSE, /* partial_inplace */
237 FALSE), /* pcrel_offset */
239 /* GNU extension to record C++ vtable member usage. */
240 HOWTO (R_MCORE_GNU_VTENTRY, /* type */
242 2, /* size (0 = byte, 1 = short, 2 = long) */
244 FALSE, /* pc_relative */
246 complain_overflow_dont,/* complain_on_overflow */
247 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
248 "R_MCORE_GNU_VTENTRY", /* name */
249 FALSE, /* partial_inplace */
252 FALSE), /* pcrel_offset */
254 HOWTO (R_MCORE_RELATIVE, /* type */
256 2, /* size (0 = byte, 1 = short, 2 = long) */
258 FALSE, /* pc_relative */
260 complain_overflow_signed, /* complain_on_overflow */
261 NULL, /* special_function */
262 "R_MCORE_RELATIVE", /* name */
263 TRUE, /* partial_inplace */
264 0xffffffff, /* src_mask */
265 0xffffffff, /* dst_mask */
266 FALSE) /* pcrel_offset */
270 #define NUM_ELEM(a) (sizeof (a) / sizeof (a)[0])
273 /* Initialize the mcore_elf_howto_table, so that linear accesses can be done. */
275 mcore_elf_howto_init (void)
279 for (i = NUM_ELEM (mcore_elf_howto_raw); i--;)
283 type = mcore_elf_howto_raw[i].type;
285 BFD_ASSERT (type < NUM_ELEM (mcore_elf_howto_table));
287 mcore_elf_howto_table [type] = & mcore_elf_howto_raw [i];
291 static reloc_howto_type *
292 mcore_elf_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
293 bfd_reloc_code_real_type code)
295 enum elf_mcore_reloc_type mcore_reloc = R_MCORE_NONE;
299 case BFD_RELOC_NONE: mcore_reloc = R_MCORE_NONE; break;
300 case BFD_RELOC_32: mcore_reloc = R_MCORE_ADDR32; break;
301 case BFD_RELOC_MCORE_PCREL_IMM8BY4: mcore_reloc = R_MCORE_PCRELIMM8BY4; break;
302 case BFD_RELOC_MCORE_PCREL_IMM11BY2: mcore_reloc = R_MCORE_PCRELIMM11BY2; break;
303 case BFD_RELOC_MCORE_PCREL_IMM4BY2: mcore_reloc = R_MCORE_PCRELIMM4BY2; break;
304 case BFD_RELOC_32_PCREL: mcore_reloc = R_MCORE_PCREL32; break;
305 case BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2: mcore_reloc = R_MCORE_PCRELJSR_IMM11BY2; break;
306 case BFD_RELOC_VTABLE_INHERIT: mcore_reloc = R_MCORE_GNU_VTINHERIT; break;
307 case BFD_RELOC_VTABLE_ENTRY: mcore_reloc = R_MCORE_GNU_VTENTRY; break;
308 case BFD_RELOC_RVA: mcore_reloc = R_MCORE_RELATIVE; break;
313 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4])
314 /* Initialize howto table if needed. */
315 mcore_elf_howto_init ();
317 return mcore_elf_howto_table [(int) mcore_reloc];
320 static reloc_howto_type *
321 mcore_elf_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
327 i < sizeof (mcore_elf_howto_raw) / sizeof (mcore_elf_howto_raw[0]);
329 if (mcore_elf_howto_raw[i].name != NULL
330 && strcasecmp (mcore_elf_howto_raw[i].name, r_name) == 0)
331 return &mcore_elf_howto_raw[i];
336 /* Set the howto pointer for a RCE ELF reloc. */
339 mcore_elf_info_to_howto (bfd * abfd ATTRIBUTE_UNUSED,
341 Elf_Internal_Rela * dst)
345 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4])
346 /* Initialize howto table if needed. */
347 mcore_elf_howto_init ();
349 r_type = ELF32_R_TYPE (dst->r_info);
350 if (r_type >= R_MCORE_max)
352 (*_bfd_error_handler) (_("%A: unrecognised MCore reloc number: %d"),
354 bfd_set_error (bfd_error_bad_value);
355 r_type = R_MCORE_NONE;
358 cache_ptr->howto = mcore_elf_howto_table [r_type];
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 (bfd * output_bfd,
392 struct bfd_link_info * info,
394 asection * input_section,
396 Elf_Internal_Rela * relocs,
397 Elf_Internal_Sym * local_syms,
398 asection ** local_sections)
400 Elf_Internal_Shdr * symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
401 struct elf_link_hash_entry ** sym_hashes = elf_sym_hashes (input_bfd);
402 Elf_Internal_Rela * rel = relocs;
403 Elf_Internal_Rela * relend = relocs + input_section->reloc_count;
404 bfd_boolean ret = TRUE;
408 ("mcore_elf_relocate_section called for %B section %A, %ld relocations%s",
411 (long) input_section->reloc_count,
412 (info->relocatable) ? " (relocatable)" : "");
415 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4]) /* Initialize howto table if needed */
416 mcore_elf_howto_init ();
418 for (; rel < relend; rel++)
420 enum elf_mcore_reloc_type r_type = (enum elf_mcore_reloc_type) ELF32_R_TYPE (rel->r_info);
421 bfd_vma offset = rel->r_offset;
422 bfd_vma addend = rel->r_addend;
423 bfd_reloc_status_type r = bfd_reloc_other;
424 asection * sec = NULL;
425 reloc_howto_type * howto;
427 Elf_Internal_Sym * sym = NULL;
428 unsigned long r_symndx;
429 struct elf_link_hash_entry * h = NULL;
430 unsigned short oldinst = 0;
432 /* Unknown relocation handling. */
433 if ((unsigned) r_type >= (unsigned) R_MCORE_max
434 || ! mcore_elf_howto_table [(int)r_type])
436 _bfd_error_handler (_("%B: Unknown relocation type %d\n"),
437 input_bfd, (int) r_type);
439 bfd_set_error (bfd_error_bad_value);
444 howto = mcore_elf_howto_table [(int) r_type];
445 r_symndx = ELF32_R_SYM (rel->r_info);
447 /* Complain about known relocation that are not yet supported. */
448 if (howto->special_function == mcore_elf_unsupported_reloc)
450 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
455 bfd_set_error (bfd_error_bad_value);
460 if (r_symndx < symtab_hdr->sh_info)
462 sym = local_syms + r_symndx;
463 sec = local_sections [r_symndx];
464 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
465 addend = rel->r_addend;
469 bfd_boolean unresolved_reloc, warned, ignored;
471 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
472 r_symndx, symtab_hdr, sym_hashes,
474 unresolved_reloc, warned, ignored);
477 if (sec != NULL && discarded_section (sec))
478 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
479 rel, 1, relend, howto, 0, contents);
481 if (info->relocatable)
489 case R_MCORE_PCRELJSR_IMM11BY2:
490 oldinst = bfd_get_16 (input_bfd, contents + offset);
491 #define MCORE_INST_BSR 0xF800
492 bfd_put_16 (input_bfd, (bfd_vma) MCORE_INST_BSR, contents + offset);
497 fprintf (stderr, "\ttype = %s (%d), symbol index = %ld, offset = %ld, addend = %ld\n",
498 howto->name, r_type, r_symndx, (long) offset, (long) addend);
501 r = _bfd_final_link_relocate
502 (howto, input_bfd, input_section, contents, offset, relocation, addend);
504 if (r != bfd_reloc_ok && r_type == R_MCORE_PCRELJSR_IMM11BY2)
506 /* Wasn't ok, back it out and give up. */
507 bfd_put_16 (input_bfd, (bfd_vma) oldinst, contents + offset);
511 if (r != bfd_reloc_ok)
520 case bfd_reloc_overflow:
528 name = bfd_elf_string_from_elf_section
529 (input_bfd, symtab_hdr->sh_link, sym->st_name);
535 name = bfd_section_name (input_bfd, sec);
538 (*info->callbacks->reloc_overflow)
539 (info, (h ? &h->root : NULL), name, howto->name,
540 (bfd_vma) 0, input_bfd, input_section, offset);
548 fprintf (stderr, "\n");
554 /* Return the section that should be marked against GC for a given
558 mcore_elf_gc_mark_hook (asection *sec,
559 struct bfd_link_info *info,
560 Elf_Internal_Rela *rel,
561 struct elf_link_hash_entry *h,
562 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 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
575 /* Update the got entry reference counts for the section being removed. */
578 mcore_elf_gc_sweep_hook (bfd * abfd ATTRIBUTE_UNUSED,
579 struct bfd_link_info * info ATTRIBUTE_UNUSED,
580 asection * sec ATTRIBUTE_UNUSED,
581 const Elf_Internal_Rela * relocs ATTRIBUTE_UNUSED)
586 /* Look through the relocs for a section during the first phase.
587 Since we don't do .gots or .plts, we just need to consider the
588 virtual table relocs for gc. */
591 mcore_elf_check_relocs (bfd * abfd,
592 struct bfd_link_info * info,
594 const Elf_Internal_Rela * relocs)
596 Elf_Internal_Shdr * symtab_hdr;
597 struct elf_link_hash_entry ** sym_hashes;
598 const Elf_Internal_Rela * rel;
599 const Elf_Internal_Rela * rel_end;
601 if (info->relocatable)
604 symtab_hdr = & elf_tdata (abfd)->symtab_hdr;
605 sym_hashes = elf_sym_hashes (abfd);
607 rel_end = relocs + sec->reloc_count;
609 for (rel = relocs; rel < rel_end; rel++)
611 struct elf_link_hash_entry * h;
612 unsigned long r_symndx;
614 r_symndx = ELF32_R_SYM (rel->r_info);
616 if (r_symndx < symtab_hdr->sh_info)
620 h = sym_hashes [r_symndx - symtab_hdr->sh_info];
621 while (h->root.type == bfd_link_hash_indirect
622 || h->root.type == bfd_link_hash_warning)
623 h = (struct elf_link_hash_entry *) h->root.u.i.link;
625 /* PR15323, ref flags aren't set for references in the same
627 h->root.non_ir_ref = 1;
630 switch (ELF32_R_TYPE (rel->r_info))
632 /* This relocation describes the C++ object vtable hierarchy.
633 Reconstruct it for later use during GC. */
634 case R_MCORE_GNU_VTINHERIT:
635 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
639 /* This relocation describes which C++ vtable entries are actually
640 used. Record for later use during GC. */
641 case R_MCORE_GNU_VTENTRY:
642 BFD_ASSERT (h != NULL);
644 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
653 static const struct bfd_elf_special_section mcore_elf_special_sections[]=
655 { STRING_COMMA_LEN (".ctors"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
656 { STRING_COMMA_LEN (".dtors"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
660 #define TARGET_BIG_SYM mcore_elf32_be_vec
661 #define TARGET_BIG_NAME "elf32-mcore-big"
662 #define TARGET_LITTLE_SYM mcore_elf32_le_vec
663 #define TARGET_LITTLE_NAME "elf32-mcore-little"
665 #define ELF_ARCH bfd_arch_mcore
666 #define ELF_MACHINE_CODE EM_MCORE
667 #define ELF_MAXPAGESIZE 0x1000 /* 4k, if we ever have 'em */
668 #define elf_info_to_howto mcore_elf_info_to_howto
669 #define elf_info_to_howto_rel NULL
671 #define bfd_elf32_bfd_merge_private_bfd_data mcore_elf_merge_private_bfd_data
672 #define bfd_elf32_bfd_set_private_flags mcore_elf_set_private_flags
673 #define bfd_elf32_bfd_reloc_type_lookup mcore_elf_reloc_type_lookup
674 #define bfd_elf32_bfd_reloc_name_lookup mcore_elf_reloc_name_lookup
675 #define elf_backend_relocate_section mcore_elf_relocate_section
676 #define elf_backend_gc_mark_hook mcore_elf_gc_mark_hook
677 #define elf_backend_gc_sweep_hook mcore_elf_gc_sweep_hook
678 #define elf_backend_check_relocs mcore_elf_check_relocs
679 #define elf_backend_special_sections mcore_elf_special_sections
681 #define elf_backend_can_gc_sections 1
682 #define elf_backend_rela_normal 1
684 #include "elf32-target.h"