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 2, /* size (0 = byte, 1 = short, 2 = long) */
115 FALSE, /* pc_relative */
117 complain_overflow_bitfield, /* 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)
343 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4])
344 /* Initialize howto table if needed. */
345 mcore_elf_howto_init ();
347 BFD_ASSERT (ELF32_R_TYPE (dst->r_info) < (unsigned int) R_MCORE_max);
349 cache_ptr->howto = mcore_elf_howto_table [ELF32_R_TYPE (dst->r_info)];
352 /* The RELOCATE_SECTION function is called by the ELF backend linker
353 to handle the relocations for a section.
355 The relocs are always passed as Rela structures; if the section
356 actually uses Rel structures, the r_addend field will always be
359 This function is responsible for adjust the section contents as
360 necessary, and (if using Rela relocs and generating a
361 relocatable output file) adjusting the reloc addend as
364 This function does not have to worry about setting the reloc
365 address or the reloc symbol index.
367 LOCAL_SYMS is a pointer to the swapped in local symbols.
369 LOCAL_SECTIONS is an array giving the section in the input file
370 corresponding to the st_shndx field of each local symbol.
372 The global hash table entry for the global symbols can be found
373 via elf_sym_hashes (input_bfd).
375 When generating relocatable output, this function must handle
376 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
377 going to be the section symbol corresponding to the output
378 section, which means that the addend must be adjusted
382 mcore_elf_relocate_section (bfd * output_bfd,
383 struct bfd_link_info * info,
385 asection * input_section,
387 Elf_Internal_Rela * relocs,
388 Elf_Internal_Sym * local_syms,
389 asection ** local_sections)
391 Elf_Internal_Shdr * symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
392 struct elf_link_hash_entry ** sym_hashes = elf_sym_hashes (input_bfd);
393 Elf_Internal_Rela * rel = relocs;
394 Elf_Internal_Rela * relend = relocs + input_section->reloc_count;
395 bfd_boolean ret = TRUE;
399 ("mcore_elf_relocate_section called for %B section %A, %ld relocations%s",
402 (long) input_section->reloc_count,
403 (info->relocatable) ? " (relocatable)" : "");
406 if (! mcore_elf_howto_table [R_MCORE_PCRELIMM8BY4]) /* Initialize howto table if needed */
407 mcore_elf_howto_init ();
409 for (; rel < relend; rel++)
411 enum elf_mcore_reloc_type r_type = (enum elf_mcore_reloc_type) ELF32_R_TYPE (rel->r_info);
412 bfd_vma offset = rel->r_offset;
413 bfd_vma addend = rel->r_addend;
414 bfd_reloc_status_type r = bfd_reloc_other;
415 asection * sec = NULL;
416 reloc_howto_type * howto;
418 Elf_Internal_Sym * sym = NULL;
419 unsigned long r_symndx;
420 struct elf_link_hash_entry * h = NULL;
421 unsigned short oldinst = 0;
423 /* Unknown relocation handling. */
424 if ((unsigned) r_type >= (unsigned) R_MCORE_max
425 || ! mcore_elf_howto_table [(int)r_type])
427 _bfd_error_handler (_("%B: Unknown relocation type %d\n"),
428 input_bfd, (int) r_type);
430 bfd_set_error (bfd_error_bad_value);
435 howto = mcore_elf_howto_table [(int) r_type];
436 r_symndx = ELF32_R_SYM (rel->r_info);
438 /* Complain about known relocation that are not yet supported. */
439 if (howto->special_function == mcore_elf_unsupported_reloc)
441 _bfd_error_handler (_("%B: Relocation %s (%d) is not currently supported.\n"),
446 bfd_set_error (bfd_error_bad_value);
451 if (r_symndx < symtab_hdr->sh_info)
453 sym = local_syms + r_symndx;
454 sec = local_sections [r_symndx];
455 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
456 addend = rel->r_addend;
460 bfd_boolean unresolved_reloc, warned, ignored;
462 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
463 r_symndx, symtab_hdr, sym_hashes,
465 unresolved_reloc, warned, ignored);
468 if (sec != NULL && discarded_section (sec))
469 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
470 rel, 1, relend, howto, 0, contents);
472 if (info->relocatable)
480 case R_MCORE_PCRELJSR_IMM11BY2:
481 oldinst = bfd_get_16 (input_bfd, contents + offset);
482 #define MCORE_INST_BSR 0xF800
483 bfd_put_16 (input_bfd, (bfd_vma) MCORE_INST_BSR, contents + offset);
488 fprintf (stderr, "\ttype = %s (%d), symbol index = %ld, offset = %ld, addend = %ld\n",
489 howto->name, r_type, r_symndx, (long) offset, (long) addend);
492 r = _bfd_final_link_relocate
493 (howto, input_bfd, input_section, contents, offset, relocation, addend);
495 if (r != bfd_reloc_ok && r_type == R_MCORE_PCRELJSR_IMM11BY2)
497 /* Wasn't ok, back it out and give up. */
498 bfd_put_16 (input_bfd, (bfd_vma) oldinst, contents + offset);
502 if (r != bfd_reloc_ok)
511 case bfd_reloc_overflow:
519 name = bfd_elf_string_from_elf_section
520 (input_bfd, symtab_hdr->sh_link, sym->st_name);
526 name = bfd_section_name (input_bfd, sec);
529 (*info->callbacks->reloc_overflow)
530 (info, (h ? &h->root : NULL), name, howto->name,
531 (bfd_vma) 0, input_bfd, input_section, offset);
539 fprintf (stderr, "\n");
545 /* Return the section that should be marked against GC for a given
549 mcore_elf_gc_mark_hook (asection *sec,
550 struct bfd_link_info *info,
551 Elf_Internal_Rela *rel,
552 struct elf_link_hash_entry *h,
553 Elf_Internal_Sym *sym)
556 switch (ELF32_R_TYPE (rel->r_info))
558 case R_MCORE_GNU_VTINHERIT:
559 case R_MCORE_GNU_VTENTRY:
563 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
566 /* Update the got entry reference counts for the section being removed. */
569 mcore_elf_gc_sweep_hook (bfd * abfd ATTRIBUTE_UNUSED,
570 struct bfd_link_info * info ATTRIBUTE_UNUSED,
571 asection * sec ATTRIBUTE_UNUSED,
572 const Elf_Internal_Rela * relocs ATTRIBUTE_UNUSED)
577 /* Look through the relocs for a section during the first phase.
578 Since we don't do .gots or .plts, we just need to consider the
579 virtual table relocs for gc. */
582 mcore_elf_check_relocs (bfd * abfd,
583 struct bfd_link_info * info,
585 const Elf_Internal_Rela * relocs)
587 Elf_Internal_Shdr * symtab_hdr;
588 struct elf_link_hash_entry ** sym_hashes;
589 const Elf_Internal_Rela * rel;
590 const Elf_Internal_Rela * rel_end;
592 if (info->relocatable)
595 symtab_hdr = & elf_tdata (abfd)->symtab_hdr;
596 sym_hashes = elf_sym_hashes (abfd);
598 rel_end = relocs + sec->reloc_count;
600 for (rel = relocs; rel < rel_end; rel++)
602 struct elf_link_hash_entry * h;
603 unsigned long r_symndx;
605 r_symndx = ELF32_R_SYM (rel->r_info);
607 if (r_symndx < symtab_hdr->sh_info)
611 h = sym_hashes [r_symndx - symtab_hdr->sh_info];
612 while (h->root.type == bfd_link_hash_indirect
613 || h->root.type == bfd_link_hash_warning)
614 h = (struct elf_link_hash_entry *) h->root.u.i.link;
616 /* PR15323, ref flags aren't set for references in the same
618 h->root.non_ir_ref = 1;
621 switch (ELF32_R_TYPE (rel->r_info))
623 /* This relocation describes the C++ object vtable hierarchy.
624 Reconstruct it for later use during GC. */
625 case R_MCORE_GNU_VTINHERIT:
626 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
630 /* This relocation describes which C++ vtable entries are actually
631 used. Record for later use during GC. */
632 case R_MCORE_GNU_VTENTRY:
633 BFD_ASSERT (h != NULL);
635 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
644 static const struct bfd_elf_special_section mcore_elf_special_sections[]=
646 { STRING_COMMA_LEN (".ctors"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
647 { STRING_COMMA_LEN (".dtors"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
651 #define TARGET_BIG_SYM mcore_elf32_be_vec
652 #define TARGET_BIG_NAME "elf32-mcore-big"
653 #define TARGET_LITTLE_SYM mcore_elf32_le_vec
654 #define TARGET_LITTLE_NAME "elf32-mcore-little"
656 #define ELF_ARCH bfd_arch_mcore
657 #define ELF_MACHINE_CODE EM_MCORE
658 #define ELF_MAXPAGESIZE 0x1000 /* 4k, if we ever have 'em */
659 #define elf_info_to_howto mcore_elf_info_to_howto
660 #define elf_info_to_howto_rel NULL
662 #define bfd_elf32_bfd_merge_private_bfd_data mcore_elf_merge_private_bfd_data
663 #define bfd_elf32_bfd_set_private_flags mcore_elf_set_private_flags
664 #define bfd_elf32_bfd_reloc_type_lookup mcore_elf_reloc_type_lookup
665 #define bfd_elf32_bfd_reloc_name_lookup mcore_elf_reloc_name_lookup
666 #define elf_backend_relocate_section mcore_elf_relocate_section
667 #define elf_backend_gc_mark_hook mcore_elf_gc_mark_hook
668 #define elf_backend_gc_sweep_hook mcore_elf_gc_sweep_hook
669 #define elf_backend_check_relocs mcore_elf_check_relocs
670 #define elf_backend_special_sections mcore_elf_special_sections
672 #define elf_backend_can_gc_sections 1
673 #define elf_backend_rela_normal 1
675 #include "elf32-target.h"