1 /* Adapteva epiphany specific support for 32-bit ELF
2 Copyright (C) 2000-2016 Free Software Foundation, Inc.
3 Contributed by Embecosm on behalf of Adapteva, 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 3 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,
20 MA 02110-1301, USA. */
26 #include "elf/epiphany.h"
27 #include "libiberty.h"
29 /* Struct used to pass miscellaneous paramaters which
30 helps to avoid overly long parameter lists. */
33 Elf_Internal_Shdr * symtab_hdr;
34 Elf_Internal_Rela * irelbase;
36 Elf_Internal_Sym * isymbuf;
39 struct epiphany_opcode
41 unsigned short opcode;
45 static bfd_boolean epiphany_relaxed = FALSE;
47 /* Relocation tables. */
48 static reloc_howto_type epiphany_elf_howto_table [] =
50 #define AHOW(t,rs,s,bs,pr,bp,co,name,sm,dm) \
52 rs, /* rightshift */ \
53 s, /* size (0 = byte, 1 = short, 2 = long) */ \
55 pr, /* pc_relative */ \
57 co, /* complain_on_overflow */ \
58 bfd_elf_generic_reloc,/* special_function */ \
60 FALSE, /* partial_inplace */ \
63 pr) /* pcrel_offset */
65 /* This reloc does nothing. */
66 AHOW (R_EPIPHANY_NONE, 0, 3,0, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_NONE", 0, 0),
68 /* 8 bit absolute (not likely) */
69 AHOW (R_EPIPHANY_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_8", 0x000000ff, 0x000000ff),
71 AHOW (R_EPIPHANY_16, 0, 1,16, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_16", 0x0000ffff, 0x00ff1fe0),
72 /* A 32 bit absolute relocation. */
73 AHOW (R_EPIPHANY_32, 0, 2,32, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_32", 0xffffffff, 0xffffffff),
75 /* 8 bit relative relocation */
76 HOWTO ( R_EPIPHANY_8_PCREL, 0, 0, 8, TRUE, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_EPIPHANY_8_PCREL", FALSE, 0x000000ff, 0x000000ff, FALSE),
77 /* 16 bit relative relocation */
78 HOWTO ( R_EPIPHANY_16_PCREL, 0, 1, 16, TRUE, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_EPIPHANY_8_PCREL", FALSE, 0x000000ff, 0x000000ff, FALSE),
79 /* 32 bit relative relocation */
80 HOWTO ( R_EPIPHANY_32_PCREL, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_EPIPHANY_8_PCREL", FALSE, 0x000000ff, 0x000000ff, FALSE),
82 /* 8 bit pc-relative relocation */
83 AHOW (R_EPIPHANY_SIMM8, 1, 0, 8, TRUE, 8, complain_overflow_signed, "R_EPIPHANY_SIMM8", 0x000000ff, 0x0000ff00),
84 /* 24 bit pc-relative relocation */
85 AHOW (R_EPIPHANY_SIMM24, 1, 2,24, TRUE, 8, complain_overflow_signed, "R_EPIPHANY_SIMM24", 0x00ffffff, 0xffffff00),
88 AHOW (R_EPIPHANY_HIGH, 0, 2,16, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_HIGH", 0x0ff01fe0, 0x0ff01fe0),
91 AHOW (R_EPIPHANY_LOW, 0, 2,16, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_LOW", 0x0ff01fe0, 0x0ff01fe0),
94 AHOW (R_EPIPHANY_SIMM11, 0, 2,11, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_SIMM11", 0x00ff0380, 0x00ff0380),
95 /* imm12 - sign-magnitude */
96 AHOW (R_EPIPHANY_IMM11, 0, 2,11, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_IMM12", 0x00ff0380, 0x00ff0380),
98 AHOW (R_EPIPHANY_IMM8, 0, 1, 8, FALSE, 8, complain_overflow_signed, "R_EPIPHANY_IMM8", 0x0000ff00, 0x0000ff00)
104 /* Map BFD reloc types to EPIPHANY ELF reloc types. */
106 static reloc_howto_type *
107 epiphany_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
108 bfd_reloc_code_real_type code)
110 /* Note that the epiphany_elf_howto_table is indxed by the R_
111 constants. Thus, the order that the howto records appear in the
112 table *must* match the order of the relocation types defined in
113 include/elf/epiphany.h. */
118 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_NONE];
120 case BFD_RELOC_EPIPHANY_SIMM8:
121 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM8];
122 case BFD_RELOC_EPIPHANY_SIMM24:
123 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM24];
125 case BFD_RELOC_8_PCREL:
126 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_8_PCREL];
127 case BFD_RELOC_16_PCREL:
128 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_16_PCREL];
129 case BFD_RELOC_32_PCREL:
130 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_32_PCREL];
133 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_8];
135 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_16];
137 return &epiphany_elf_howto_table[ (int) R_EPIPHANY_32];
139 case BFD_RELOC_EPIPHANY_HIGH:
140 return & epiphany_elf_howto_table[ (int) R_EPIPHANY_HIGH];
141 case BFD_RELOC_EPIPHANY_LOW:
142 return & epiphany_elf_howto_table[ (int) R_EPIPHANY_LOW];
144 case BFD_RELOC_EPIPHANY_SIMM11:
145 return & epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM11];
146 case BFD_RELOC_EPIPHANY_IMM11:
147 return & epiphany_elf_howto_table[ (int) R_EPIPHANY_IMM11];
149 case BFD_RELOC_EPIPHANY_IMM8:
150 return & epiphany_elf_howto_table[ (int) R_EPIPHANY_IMM8];
153 /* Pacify gcc -Wall. */
159 static reloc_howto_type *
160 epiphany_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
164 for (i = 0; i < ARRAY_SIZE (epiphany_elf_howto_table); i++)
165 if (epiphany_elf_howto_table[i].name != NULL
166 && strcasecmp (epiphany_elf_howto_table[i].name, r_name) == 0)
167 return &epiphany_elf_howto_table[i];
172 #define PAGENO(ABSADDR) ((ABSADDR) & 0xFFFFC000)
173 #define BASEADDR(SEC) ((SEC)->output_section->vma + (SEC)->output_offset)
175 /* This function handles relaxing for the epiphany.
176 Dummy placeholder for future optimizations. */
179 epiphany_elf_relax_section (bfd *abfd, asection *sec,
180 struct bfd_link_info *link_info,
183 Elf_Internal_Shdr *symtab_hdr;
184 Elf_Internal_Rela *internal_relocs;
185 bfd_byte *contents = NULL;
186 Elf_Internal_Sym *isymbuf = NULL;
187 static asection * first_section = NULL;
188 static unsigned long search_addr;
189 static unsigned long page_start = 0;
190 static unsigned long page_end = 0;
191 static unsigned int pass = 0;
192 static bfd_boolean new_pass = FALSE;
193 static bfd_boolean changed = FALSE;
194 struct misc misc ATTRIBUTE_UNUSED;
197 /* Assume nothing changes. */
200 if (first_section == NULL)
202 epiphany_relaxed = TRUE;
206 if (first_section == sec)
212 /* We don't have to do anything for a relocatable link,
213 if this section does not have relocs, or if this is
214 not a code section. */
215 if (bfd_link_relocatable (link_info)
216 || (sec->flags & SEC_RELOC) == 0
217 || sec->reloc_count == 0
218 || (sec->flags & SEC_CODE) == 0)
221 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
223 internal_relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
224 link_info->keep_memory);
225 if (internal_relocs == NULL)
228 /* Make sure the stac.rela stuff gets read in. */
229 stab = bfd_get_section_by_name (abfd, ".stab");
233 /* So stab does exits. */
234 Elf_Internal_Rela * irelbase ATTRIBUTE_UNUSED;
236 irelbase = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
237 link_info->keep_memory);
240 /* Get section contents cached copy if it exists. */
241 if (contents == NULL)
243 /* Get cached copy if it exists. */
244 if (elf_section_data (sec)->this_hdr.contents != NULL)
245 contents = elf_section_data (sec)->this_hdr.contents;
248 /* Go get them off disk. */
249 if (!bfd_malloc_and_get_section (abfd, sec, &contents))
254 /* Read this BFD's symbols cached copy if it exists. */
255 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
257 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
259 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
260 symtab_hdr->sh_info, 0,
266 misc.symtab_hdr = symtab_hdr;
267 misc.isymbuf = isymbuf;
268 misc.irelbase = internal_relocs;
269 misc.contents = contents;
271 /* This is where all the relaxation actually get done. */
272 if ((pass == 1) || (new_pass && !changed))
274 /* On the first pass we simply search for the lowest page that
275 we havn't relaxed yet. Note that the pass count is reset
276 each time a page is complete in order to move on to the next page.
277 If we can't find any more pages then we are finished. */
282 changed = TRUE; /* Pre-initialize to break out of pass 1. */
283 search_addr = 0xFFFFFFFF;
286 if ((BASEADDR (sec) + sec->size < search_addr)
287 && (BASEADDR (sec) + sec->size > page_end))
289 if (BASEADDR (sec) <= page_end)
290 search_addr = page_end + 1;
292 search_addr = BASEADDR (sec);
294 /* Found a page => more work to do. */
304 page_start = PAGENO (search_addr);
305 page_end = page_start | 0x00003FFF;
308 /* Only process sections in range. */
309 if ((BASEADDR (sec) + sec->size >= page_start)
310 && (BASEADDR (sec) <= page_end))
313 if (!epiphany_elf_relax_section_page (abfd, sec, &changed, &misc,
314 page_start, page_end))
321 /* Perform some house keeping after relaxing the section. */
324 && symtab_hdr->contents != (unsigned char *) isymbuf)
326 if (! link_info->keep_memory)
329 symtab_hdr->contents = (unsigned char *) isymbuf;
333 && elf_section_data (sec)->this_hdr.contents != contents)
335 if (! link_info->keep_memory)
339 /* Cache the section contents for elf_link_input_bfd. */
340 elf_section_data (sec)->this_hdr.contents = contents;
344 if (internal_relocs != NULL
345 && elf_section_data (sec)->relocs != internal_relocs)
346 free (internal_relocs);
352 && symtab_hdr->contents != (unsigned char *) isymbuf)
355 && elf_section_data (sec)->this_hdr.contents != contents)
357 if (internal_relocs != NULL
358 && elf_section_data (sec)->relocs != internal_relocs)
359 free (internal_relocs);
363 /* Set the howto pointer for a EPIPHANY ELF reloc. */
366 epiphany_info_to_howto_rela (bfd * abfd ATTRIBUTE_UNUSED,
368 Elf_Internal_Rela * dst)
372 r_type = ELF32_R_TYPE (dst->r_info);
373 if (r_type >= (unsigned int) R_EPIPHANY_max)
375 _bfd_error_handler (_("%B: invalid Epiphany reloc number: %d"), abfd, r_type);
378 cache_ptr->howto = & epiphany_elf_howto_table [r_type];
381 /* Perform a single relocation.
382 By default we use the standard BFD routines. */
384 static bfd_reloc_status_type
385 epiphany_final_link_relocate (reloc_howto_type * howto,
387 asection * input_section,
389 Elf_Internal_Rela * rel,
394 /* Handle 16 bit immediates. */
395 case R_EPIPHANY_HIGH:
396 relocation += rel->r_addend;
401 relocation += rel->r_addend;
403 relocation = ((relocation & 0xff00L) << 12)
404 | ((relocation & 0x00ffL) << 5);
405 /* Sanity check the address. */
406 if (rel->r_offset > bfd_get_section_limit (input_bfd, input_section))
407 return bfd_reloc_outofrange;
409 return _bfd_relocate_contents (howto, input_bfd, relocation,
410 contents + rel->r_offset);
412 case R_EPIPHANY_SIMM11:
413 relocation += rel->r_addend;
414 /* Check signed overflow. */
415 if ((int)relocation > 1023 || (int)relocation < -1024)
416 return bfd_reloc_outofrange;
419 case R_EPIPHANY_IMM11:
420 relocation += rel->r_addend;
421 if ((unsigned int) relocation > 0x7ff)
422 return bfd_reloc_outofrange;
425 relocation = (((relocation & 7) << 5)
426 | ((relocation & 0x7f8 ) << 13));
427 return _bfd_relocate_contents (howto, input_bfd, relocation,
428 contents + rel->r_offset);
430 /* Pass others through. */
435 /* Only install relocation if above tests did not disqualify it. */
436 return _bfd_final_link_relocate (howto, input_bfd, input_section,
437 contents, rel->r_offset,
438 relocation, rel->r_addend);
441 /* Relocate an EPIPHANY ELF section.
443 The RELOCATE_SECTION function is called by the new ELF backend linker
444 to handle the relocations for a section.
446 The relocs are always passed as Rela structures; if the section
447 actually uses Rel structures, the r_addend field will always be
450 This function is responsible for adjusting the section contents as
451 necessary, and (if using Rela relocs and generating a relocatable
452 output file) adjusting the reloc addend as necessary.
454 This function does not have to worry about setting the reloc
455 address or the reloc symbol index.
457 LOCAL_SYMS is a pointer to the swapped in local symbols.
459 LOCAL_SECTIONS is an array giving the section in the input file
460 corresponding to the st_shndx field of each local symbol.
462 The global hash table entry for the global symbols can be found
463 via elf_sym_hashes (input_bfd).
465 When generating relocatable output, this function must handle
466 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
467 going to be the section symbol corresponding to the output
468 section, which means that the addend must be adjusted
472 epiphany_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
473 struct bfd_link_info *info,
475 asection *input_section,
477 Elf_Internal_Rela *relocs,
478 Elf_Internal_Sym *local_syms,
479 asection **local_sections)
481 Elf_Internal_Shdr *symtab_hdr;
482 struct elf_link_hash_entry **sym_hashes;
483 Elf_Internal_Rela *rel;
484 Elf_Internal_Rela *relend;
486 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
487 sym_hashes = elf_sym_hashes (input_bfd);
488 relend = relocs + input_section->reloc_count;
490 for (rel = relocs; rel < relend; rel ++)
492 reloc_howto_type * howto;
493 unsigned long r_symndx;
494 Elf_Internal_Sym * sym;
496 struct elf_link_hash_entry * h;
498 bfd_reloc_status_type r;
499 const char * name = NULL;
500 int r_type ATTRIBUTE_UNUSED;
502 r_type = ELF32_R_TYPE (rel->r_info);
503 r_symndx = ELF32_R_SYM (rel->r_info);
504 howto = epiphany_elf_howto_table + ELF32_R_TYPE (rel->r_info);
509 if (r_symndx < symtab_hdr->sh_info)
511 sym = local_syms + r_symndx;
512 sec = local_sections [r_symndx];
513 relocation = BASEADDR (sec) + sym->st_value;
515 name = bfd_elf_string_from_elf_section
516 (input_bfd, symtab_hdr->sh_link, sym->st_name);
517 name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
521 bfd_boolean warned ATTRIBUTE_UNUSED;
522 bfd_boolean unresolved_reloc ATTRIBUTE_UNUSED;
523 bfd_boolean ignored ATTRIBUTE_UNUSED;
525 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
526 r_symndx, symtab_hdr, sym_hashes,
528 unresolved_reloc, warned, ignored);
530 name = h->root.root.string;
533 if (sec != NULL && discarded_section (sec))
534 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
535 rel, 1, relend, howto, 0, contents);
537 if (bfd_link_relocatable (info))
540 /* Finally, the sole EPIPHANY-specific part. */
541 r = epiphany_final_link_relocate (howto, input_bfd, input_section,
542 contents, rel, relocation);
544 if (r != bfd_reloc_ok)
546 const char * msg = NULL;
550 case bfd_reloc_overflow:
551 (*info->callbacks->reloc_overflow)
552 (info, (h ? &h->root : NULL), name, howto->name,
553 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
556 case bfd_reloc_undefined:
557 (*info->callbacks->undefined_symbol)
558 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
561 case bfd_reloc_outofrange:
562 msg = _("internal error: out of range error");
565 /* This is how epiphany_final_link_relocate tells us of a
566 non-kosher reference between insn & data address spaces. */
567 case bfd_reloc_notsupported:
568 if (sym != NULL) /* Only if it's not an unresolved symbol. */
569 msg = _("unsupported relocation between data/insn address spaces");
572 case bfd_reloc_dangerous:
573 msg = _("internal error: dangerous relocation");
577 msg = _("internal error: unknown error");
582 (*info->callbacks->warning) (info, msg, name, input_bfd,
583 input_section, rel->r_offset);
590 /* We only have a little-endian target. */
591 #define TARGET_LITTLE_SYM epiphany_elf32_vec
592 #define TARGET_LITTLE_NAME "elf32-epiphany"
594 #define ELF_ARCH bfd_arch_epiphany
595 #define ELF_MACHINE_CODE EM_ADAPTEVA_EPIPHANY
597 #define ELF_MAXPAGESIZE 0x8000 /* No pages on the EPIPHANY. */
599 #define elf_info_to_howto_rel NULL
600 #define elf_info_to_howto epiphany_info_to_howto_rela
602 #define elf_backend_can_gc_sections 1
603 #define elf_backend_rela_normal 1
604 #define elf_backend_relocate_section epiphany_elf_relocate_section
606 #define elf_symbol_leading_char '_'
607 #define bfd_elf32_bfd_reloc_type_lookup epiphany_reloc_type_lookup
608 #define bfd_elf32_bfd_reloc_name_lookup epiphany_reloc_name_lookup
609 #define bfd_elf32_bfd_relax_section epiphany_elf_relax_section
611 #include "elf32-target.h"