1 /* Adapteva epiphany specific support for 32-bit ELF
2 Copyright (C) 2000-2017 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 /* xgettext:c-format */
376 _bfd_error_handler (_("%B: invalid Epiphany reloc number: %d"), abfd, r_type);
379 cache_ptr->howto = & epiphany_elf_howto_table [r_type];
382 /* Perform a single relocation.
383 By default we use the standard BFD routines. */
385 static bfd_reloc_status_type
386 epiphany_final_link_relocate (reloc_howto_type * howto,
388 asection * input_section,
390 Elf_Internal_Rela * rel,
395 /* Handle 16 bit immediates. */
396 case R_EPIPHANY_HIGH:
397 relocation += rel->r_addend;
402 relocation += rel->r_addend;
404 relocation = ((relocation & 0xff00L) << 12)
405 | ((relocation & 0x00ffL) << 5);
406 /* Sanity check the address. */
407 if (rel->r_offset > bfd_get_section_limit (input_bfd, input_section))
408 return bfd_reloc_outofrange;
410 return _bfd_relocate_contents (howto, input_bfd, relocation,
411 contents + rel->r_offset);
413 case R_EPIPHANY_SIMM11:
414 relocation += rel->r_addend;
415 /* Check signed overflow. */
416 if ((int)relocation > 1023 || (int)relocation < -1024)
417 return bfd_reloc_outofrange;
420 case R_EPIPHANY_IMM11:
421 relocation += rel->r_addend;
422 if ((unsigned int) relocation > 0x7ff)
423 return bfd_reloc_outofrange;
426 relocation = (((relocation & 7) << 5)
427 | ((relocation & 0x7f8 ) << 13));
428 return _bfd_relocate_contents (howto, input_bfd, relocation,
429 contents + rel->r_offset);
431 /* Pass others through. */
436 /* Only install relocation if above tests did not disqualify it. */
437 return _bfd_final_link_relocate (howto, input_bfd, input_section,
438 contents, rel->r_offset,
439 relocation, rel->r_addend);
442 /* Relocate an EPIPHANY ELF section.
444 The RELOCATE_SECTION function is called by the new ELF backend linker
445 to handle the relocations for a section.
447 The relocs are always passed as Rela structures; if the section
448 actually uses Rel structures, the r_addend field will always be
451 This function is responsible for adjusting the section contents as
452 necessary, and (if using Rela relocs and generating a relocatable
453 output file) adjusting the reloc addend as necessary.
455 This function does not have to worry about setting the reloc
456 address or the reloc symbol index.
458 LOCAL_SYMS is a pointer to the swapped in local symbols.
460 LOCAL_SECTIONS is an array giving the section in the input file
461 corresponding to the st_shndx field of each local symbol.
463 The global hash table entry for the global symbols can be found
464 via elf_sym_hashes (input_bfd).
466 When generating relocatable output, this function must handle
467 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
468 going to be the section symbol corresponding to the output
469 section, which means that the addend must be adjusted
473 epiphany_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
474 struct bfd_link_info *info,
476 asection *input_section,
478 Elf_Internal_Rela *relocs,
479 Elf_Internal_Sym *local_syms,
480 asection **local_sections)
482 Elf_Internal_Shdr *symtab_hdr;
483 struct elf_link_hash_entry **sym_hashes;
484 Elf_Internal_Rela *rel;
485 Elf_Internal_Rela *relend;
487 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
488 sym_hashes = elf_sym_hashes (input_bfd);
489 relend = relocs + input_section->reloc_count;
491 for (rel = relocs; rel < relend; rel ++)
493 reloc_howto_type * howto;
494 unsigned long r_symndx;
495 Elf_Internal_Sym * sym;
497 struct elf_link_hash_entry * h;
499 bfd_reloc_status_type r;
500 const char * name = NULL;
501 int r_type ATTRIBUTE_UNUSED;
503 r_type = ELF32_R_TYPE (rel->r_info);
504 r_symndx = ELF32_R_SYM (rel->r_info);
505 howto = epiphany_elf_howto_table + ELF32_R_TYPE (rel->r_info);
510 if (r_symndx < symtab_hdr->sh_info)
512 sym = local_syms + r_symndx;
513 sec = local_sections [r_symndx];
514 relocation = BASEADDR (sec) + sym->st_value;
516 name = bfd_elf_string_from_elf_section
517 (input_bfd, symtab_hdr->sh_link, sym->st_name);
518 name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
522 bfd_boolean warned ATTRIBUTE_UNUSED;
523 bfd_boolean unresolved_reloc ATTRIBUTE_UNUSED;
524 bfd_boolean ignored ATTRIBUTE_UNUSED;
526 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
527 r_symndx, symtab_hdr, sym_hashes,
529 unresolved_reloc, warned, ignored);
531 name = h->root.root.string;
534 if (sec != NULL && discarded_section (sec))
535 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
536 rel, 1, relend, howto, 0, contents);
538 if (bfd_link_relocatable (info))
541 /* Finally, the sole EPIPHANY-specific part. */
542 r = epiphany_final_link_relocate (howto, input_bfd, input_section,
543 contents, rel, relocation);
545 if (r != bfd_reloc_ok)
547 const char * msg = NULL;
551 case bfd_reloc_overflow:
552 (*info->callbacks->reloc_overflow)
553 (info, (h ? &h->root : NULL), name, howto->name,
554 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
557 case bfd_reloc_undefined:
558 (*info->callbacks->undefined_symbol)
559 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
562 case bfd_reloc_outofrange:
563 msg = _("internal error: out of range error");
566 /* This is how epiphany_final_link_relocate tells us of a
567 non-kosher reference between insn & data address spaces. */
568 case bfd_reloc_notsupported:
569 if (sym != NULL) /* Only if it's not an unresolved symbol. */
570 msg = _("unsupported relocation between data/insn address spaces");
573 case bfd_reloc_dangerous:
574 msg = _("internal error: dangerous relocation");
578 msg = _("internal error: unknown error");
583 (*info->callbacks->warning) (info, msg, name, input_bfd,
584 input_section, rel->r_offset);
591 /* We only have a little-endian target. */
592 #define TARGET_LITTLE_SYM epiphany_elf32_vec
593 #define TARGET_LITTLE_NAME "elf32-epiphany"
595 #define ELF_ARCH bfd_arch_epiphany
596 #define ELF_MACHINE_CODE EM_ADAPTEVA_EPIPHANY
598 #define ELF_MAXPAGESIZE 0x8000 /* No pages on the EPIPHANY. */
600 #define elf_info_to_howto_rel NULL
601 #define elf_info_to_howto epiphany_info_to_howto_rela
603 #define elf_backend_can_gc_sections 1
604 #define elf_backend_rela_normal 1
605 #define elf_backend_relocate_section epiphany_elf_relocate_section
607 #define elf_symbol_leading_char '_'
608 #define bfd_elf32_bfd_reloc_type_lookup epiphany_reloc_type_lookup
609 #define bfd_elf32_bfd_reloc_name_lookup epiphany_reloc_name_lookup
610 #define bfd_elf32_bfd_relax_section epiphany_elf_relax_section
612 #include "elf32-target.h"