/* Adapteva epiphany specific support for 32-bit ELF
Copyright (C) 2000-2014 Free Software Foundation, Inc.
Contributed by Embecosm on behalf of Adapteva, Inc.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
#include "elf-bfd.h"
#include "elf/epiphany.h"
#include "libiberty.h"
/* Struct used to pass miscellaneous paramaters which
helps to avoid overly long parameter lists. */
struct misc
{
Elf_Internal_Shdr * symtab_hdr;
Elf_Internal_Rela * irelbase;
bfd_byte * contents;
Elf_Internal_Sym * isymbuf;
};
struct epiphany_opcode
{
unsigned short opcode;
unsigned short mask;
};
static bfd_boolean epiphany_relaxed = FALSE;
/* Relocation tables. */
static reloc_howto_type epiphany_elf_howto_table [] =
{
#define AHOW(t,rs,s,bs,pr,bp,co,name,sm,dm) \
HOWTO(t, /* type */ \
rs, /* rightshift */ \
s, /* size (0 = byte, 1 = short, 2 = long) */ \
bs, /* bitsize */ \
pr, /* pc_relative */ \
bp, /* bitpos */ \
co, /* complain_on_overflow */ \
bfd_elf_generic_reloc,/* special_function */ \
name, /* name */ \
FALSE, /* partial_inplace */ \
sm, /* src_mask */ \
dm, /* dst_mask */ \
pr) /* pcrel_offset */
/* This reloc does nothing. */
AHOW (R_EPIPHANY_NONE, 0, 0,32, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_NONE", 0, 0),
/* 8 bit absolute (not likely) */
AHOW (R_EPIPHANY_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_8", 0x000000ff, 0x000000ff),
/* 16 bit absolute */
AHOW (R_EPIPHANY_16, 0, 1,16, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_16", 0x0000ffff, 0x00ff1fe0),
/* A 32 bit absolute relocation. */
AHOW (R_EPIPHANY_32, 0, 2,32, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_32", 0xffffffff, 0xffffffff),
/* 8 bit relative relocation */
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),
/* 16 bit relative relocation */
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),
/* 32 bit relative relocation */
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),
/* 8 bit pc-relative relocation */
AHOW (R_EPIPHANY_SIMM8, 1, 0, 8, TRUE, 8, complain_overflow_signed, "R_EPIPHANY_SIMM8", 0x000000ff, 0x0000ff00),
/* 24 bit pc-relative relocation */
AHOW (R_EPIPHANY_SIMM24, 1, 2,24, TRUE, 8, complain_overflow_signed, "R_EPIPHANY_SIMM24", 0x00ffffff, 0xffffff00),
/* %HIGH(EA) */
AHOW (R_EPIPHANY_HIGH, 0, 2,16, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_HIGH", 0x0ff01fe0, 0x0ff01fe0),
/* %LOW(EA) */
AHOW (R_EPIPHANY_LOW, 0, 2,16, FALSE, 0, complain_overflow_dont, "R_EPIPHANY_LOW", 0x0ff01fe0, 0x0ff01fe0),
/* simm11 */
AHOW (R_EPIPHANY_SIMM11, 0, 2,11, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_SIMM11", 0x00ff0380, 0x00ff0380),
/* imm12 - sign-magnitude */
AHOW (R_EPIPHANY_IMM11, 0, 2,11, FALSE, 0, complain_overflow_bitfield, "R_EPIPHANY_IMM12", 0x00ff0380, 0x00ff0380),
/* imm8 */
AHOW (R_EPIPHANY_IMM8, 0, 1, 8, FALSE, 8, complain_overflow_signed, "R_EPIPHANY_IMM8", 0x0000ff00, 0x0000ff00)
};
#undef AHOW
/* Map BFD reloc types to EPIPHANY ELF reloc types. */
static reloc_howto_type *
epiphany_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
bfd_reloc_code_real_type code)
{
/* Note that the epiphany_elf_howto_table is indxed by the R_
constants. Thus, the order that the howto records appear in the
table *must* match the order of the relocation types defined in
include/elf/epiphany.h. */
switch (code)
{
case BFD_RELOC_NONE:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_NONE];
case BFD_RELOC_EPIPHANY_SIMM8:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM8];
case BFD_RELOC_EPIPHANY_SIMM24:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM24];
case BFD_RELOC_8_PCREL:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_8_PCREL];
case BFD_RELOC_16_PCREL:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_16_PCREL];
case BFD_RELOC_32_PCREL:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_32_PCREL];
case BFD_RELOC_8:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_8];
case BFD_RELOC_16:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_16];
case BFD_RELOC_32:
return &epiphany_elf_howto_table[ (int) R_EPIPHANY_32];
case BFD_RELOC_EPIPHANY_HIGH:
return & epiphany_elf_howto_table[ (int) R_EPIPHANY_HIGH];
case BFD_RELOC_EPIPHANY_LOW:
return & epiphany_elf_howto_table[ (int) R_EPIPHANY_LOW];
case BFD_RELOC_EPIPHANY_SIMM11:
return & epiphany_elf_howto_table[ (int) R_EPIPHANY_SIMM11];
case BFD_RELOC_EPIPHANY_IMM11:
return & epiphany_elf_howto_table[ (int) R_EPIPHANY_IMM11];
case BFD_RELOC_EPIPHANY_IMM8:
return & epiphany_elf_howto_table[ (int) R_EPIPHANY_IMM8];
default:
/* Pacify gcc -Wall. */
return NULL;
}
return NULL;
}
static reloc_howto_type *
epiphany_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE (epiphany_elf_howto_table); i++)
if (epiphany_elf_howto_table[i].name != NULL
&& strcasecmp (epiphany_elf_howto_table[i].name, r_name) == 0)
return &epiphany_elf_howto_table[i];
return NULL;
}
#define PAGENO(ABSADDR) ((ABSADDR) & 0xFFFFC000)
#define BASEADDR(SEC) ((SEC)->output_section->vma + (SEC)->output_offset)
/* This function handles relaxing for the epiphany.
Dummy placeholder for future optimizations. */
static bfd_boolean
epiphany_elf_relax_section (bfd *abfd, asection *sec,
struct bfd_link_info *link_info,
bfd_boolean *again)
{
Elf_Internal_Shdr *symtab_hdr;
Elf_Internal_Rela *internal_relocs;
bfd_byte *contents = NULL;
Elf_Internal_Sym *isymbuf = NULL;
static asection * first_section = NULL;
static unsigned long search_addr;
static unsigned long page_start = 0;
static unsigned long page_end = 0;
static unsigned int pass = 0;
static bfd_boolean new_pass = FALSE;
static bfd_boolean changed = FALSE;
struct misc misc ATTRIBUTE_UNUSED;
asection *stab;
/* Assume nothing changes. */
*again = FALSE;
if (first_section == NULL)
{
epiphany_relaxed = TRUE;
first_section = sec;
}
if (first_section == sec)
{
pass++;
new_pass = TRUE;
}
/* We don't have to do anything for a relocatable link,
if this section does not have relocs, or if this is
not a code section. */
if (link_info->relocatable
|| (sec->flags & SEC_RELOC) == 0
|| sec->reloc_count == 0
|| (sec->flags & SEC_CODE) == 0)
return TRUE;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
internal_relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
link_info->keep_memory);
if (internal_relocs == NULL)
goto error_return;
/* Make sure the stac.rela stuff gets read in. */
stab = bfd_get_section_by_name (abfd, ".stab");
if (stab)
{
/* So stab does exits. */
Elf_Internal_Rela * irelbase ATTRIBUTE_UNUSED;
irelbase = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
link_info->keep_memory);
}
/* Get section contents cached copy if it exists. */
if (contents == NULL)
{
/* Get cached copy if it exists. */
if (elf_section_data (sec)->this_hdr.contents != NULL)
contents = elf_section_data (sec)->this_hdr.contents;
else
{
/* Go get them off disk. */
if (!bfd_malloc_and_get_section (abfd, sec, &contents))
goto error_return;
}
}
/* Read this BFD's symbols cached copy if it exists. */
if (isymbuf == NULL && symtab_hdr->sh_info != 0)
{
isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
if (isymbuf == NULL)
isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
symtab_hdr->sh_info, 0,
NULL, NULL, NULL);
if (isymbuf == NULL)
goto error_return;
}
misc.symtab_hdr = symtab_hdr;
misc.isymbuf = isymbuf;
misc.irelbase = internal_relocs;
misc.contents = contents;
/* This is where all the relaxation actually get done. */
if ((pass == 1) || (new_pass && !changed))
{
/* On the first pass we simply search for the lowest page that
we havn't relaxed yet. Note that the pass count is reset
each time a page is complete in order to move on to the next page.
If we can't find any more pages then we are finished. */
if (new_pass)
{
pass = 1;
new_pass = FALSE;
changed = TRUE; /* Pre-initialize to break out of pass 1. */
search_addr = 0xFFFFFFFF;
}
if ((BASEADDR (sec) + sec->size < search_addr)
&& (BASEADDR (sec) + sec->size > page_end))
{
if (BASEADDR (sec) <= page_end)
search_addr = page_end + 1;
else
search_addr = BASEADDR (sec);
/* Found a page => more work to do. */
*again = TRUE;
}
}
else
{
if (new_pass)
{
new_pass = FALSE;
changed = FALSE;
page_start = PAGENO (search_addr);
page_end = page_start | 0x00003FFF;
}
/* Only process sections in range. */
if ((BASEADDR (sec) + sec->size >= page_start)
&& (BASEADDR (sec) <= page_end))
{
#if 0
if (!epiphany_elf_relax_section_page (abfd, sec, &changed, &misc,
page_start, page_end))
#endif
return FALSE;
}
*again = TRUE;
}
/* Perform some house keeping after relaxing the section. */
if (isymbuf != NULL
&& symtab_hdr->contents != (unsigned char *) isymbuf)
{
if (! link_info->keep_memory)
free (isymbuf);
else
symtab_hdr->contents = (unsigned char *) isymbuf;
}
if (contents != NULL
&& elf_section_data (sec)->this_hdr.contents != contents)
{
if (! link_info->keep_memory)
free (contents);
else
{
/* Cache the section contents for elf_link_input_bfd. */
elf_section_data (sec)->this_hdr.contents = contents;
}
}
if (internal_relocs != NULL
&& elf_section_data (sec)->relocs != internal_relocs)
free (internal_relocs);
return TRUE;
error_return:
if (isymbuf != NULL
&& symtab_hdr->contents != (unsigned char *) isymbuf)
free (isymbuf);
if (contents != NULL
&& elf_section_data (sec)->this_hdr.contents != contents)
free (contents);
if (internal_relocs != NULL
&& elf_section_data (sec)->relocs != internal_relocs)
free (internal_relocs);
return FALSE;
}
/* Set the howto pointer for a EPIPHANY ELF reloc. */
static void
epiphany_info_to_howto_rela (bfd * abfd ATTRIBUTE_UNUSED,
arelent * cache_ptr,
Elf_Internal_Rela * dst)
{
unsigned int r_type;
r_type = ELF32_R_TYPE (dst->r_info);
cache_ptr->howto = & epiphany_elf_howto_table [r_type];
}
/* Perform a single relocation.
By default we use the standard BFD routines. */
static bfd_reloc_status_type
epiphany_final_link_relocate (reloc_howto_type * howto,
bfd * input_bfd,
asection * input_section,
bfd_byte * contents,
Elf_Internal_Rela * rel,
bfd_vma relocation)
{
switch (howto->type)
{
/* Handle 16 bit immediates. */
case R_EPIPHANY_HIGH:
relocation += rel->r_addend;
relocation >>= 16;
goto common;
case R_EPIPHANY_LOW:
relocation += rel->r_addend;
common:
relocation = ((relocation & 0xff00L) << 12)
| ((relocation & 0x00ffL) << 5);
/* Sanity check the address. */
if (rel->r_offset > bfd_get_section_limit (input_bfd, input_section))
return bfd_reloc_outofrange;
return _bfd_relocate_contents (howto, input_bfd, relocation,
contents + rel->r_offset);
case R_EPIPHANY_SIMM11:
relocation += rel->r_addend;
/* Check signed overflow. */
if ((int)relocation > 1023 || (int)relocation < -1024)
return bfd_reloc_outofrange;
goto disp11;
case R_EPIPHANY_IMM11:
relocation += rel->r_addend;
if ((unsigned int) relocation > 0x7ff)
return bfd_reloc_outofrange;
disp11:
relocation = ((relocation & 7) << 5)
|| ((relocation & 0x7f8 ) << 13);
return _bfd_relocate_contents (howto, input_bfd, relocation,
contents + rel->r_offset);
/* Pass others through. */
default:
break;
}
/* Only install relocation if above tests did not disqualify it. */
return _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, rel->r_addend);
}
/* Relocate an EPIPHANY ELF section.
The RELOCATE_SECTION function is called by the new ELF backend linker
to handle the relocations for a section.
The relocs are always passed as Rela structures; if the section
actually uses Rel structures, the r_addend field will always be
zero.
This function is responsible for adjusting the section contents as
necessary, and (if using Rela relocs and generating a relocatable
output file) adjusting the reloc addend as necessary.
This function does not have to worry about setting the reloc
address or the reloc symbol index.
LOCAL_SYMS is a pointer to the swapped in local symbols.
LOCAL_SECTIONS is an array giving the section in the input file
corresponding to the st_shndx field of each local symbol.
The global hash table entry for the global symbols can be found
via elf_sym_hashes (input_bfd).
When generating relocatable output, this function must handle
STB_LOCAL/STT_SECTION symbols specially. The output symbol is
going to be the section symbol corresponding to the output
section, which means that the addend must be adjusted
accordingly. */
static bfd_boolean
epiphany_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
struct bfd_link_info *info,
bfd *input_bfd,
asection *input_section,
bfd_byte *contents,
Elf_Internal_Rela *relocs,
Elf_Internal_Sym *local_syms,
asection **local_sections)
{
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
Elf_Internal_Rela *rel;
Elf_Internal_Rela *relend;
symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (input_bfd);
relend = relocs + input_section->reloc_count;
for (rel = relocs; rel < relend; rel ++)
{
reloc_howto_type * howto;
unsigned long r_symndx;
Elf_Internal_Sym * sym;
asection * sec;
struct elf_link_hash_entry * h;
bfd_vma relocation;
bfd_reloc_status_type r;
const char * name = NULL;
int r_type ATTRIBUTE_UNUSED;
r_type = ELF32_R_TYPE (rel->r_info);
r_symndx = ELF32_R_SYM (rel->r_info);
howto = epiphany_elf_howto_table + ELF32_R_TYPE (rel->r_info);
h = NULL;
sym = NULL;
sec = NULL;
if (r_symndx < symtab_hdr->sh_info)
{
sym = local_syms + r_symndx;
sec = local_sections [r_symndx];
relocation = BASEADDR (sec) + sym->st_value;
name = bfd_elf_string_from_elf_section
(input_bfd, symtab_hdr->sh_link, sym->st_name);
name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
}
else
{
bfd_boolean warned ATTRIBUTE_UNUSED;
bfd_boolean unresolved_reloc ATTRIBUTE_UNUSED;
bfd_boolean ignored ATTRIBUTE_UNUSED;
RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
r_symndx, symtab_hdr, sym_hashes,
h, sec, relocation,
unresolved_reloc, warned, ignored);
name = h->root.root.string;
}
if (sec != NULL && discarded_section (sec))
RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
rel, 1, relend, howto, 0, contents);
if (info->relocatable)
continue;
/* Finally, the sole EPIPHANY-specific part. */
r = epiphany_final_link_relocate (howto, input_bfd, input_section,
contents, rel, relocation);
if (r != bfd_reloc_ok)
{
const char * msg = NULL;
switch (r)
{
case bfd_reloc_overflow:
r = info->callbacks->reloc_overflow
(info, (h ? &h->root : NULL), name, howto->name,
(bfd_vma) 0, input_bfd, input_section, rel->r_offset);
break;
case bfd_reloc_undefined:
r = info->callbacks->undefined_symbol
(info, name, input_bfd, input_section, rel->r_offset, TRUE);
break;
case bfd_reloc_outofrange:
msg = _("internal error: out of range error");
break;
/* This is how epiphany_final_link_relocate tells us of a
non-kosher reference between insn & data address spaces. */
case bfd_reloc_notsupported:
if (sym != NULL) /* Only if it's not an unresolved symbol. */
msg = _("unsupported relocation between data/insn address spaces");
break;
case bfd_reloc_dangerous:
msg = _("internal error: dangerous relocation");
break;
default:
msg = _("internal error: unknown error");
break;
}
if (msg)
r = info->callbacks->warning
(info, msg, name, input_bfd, input_section, rel->r_offset);
if (! r)
return FALSE;
}
}
return TRUE;
}
/* We only have a little-endian target. */
#define TARGET_LITTLE_SYM epiphany_elf32_vec
#define TARGET_LITTLE_NAME "elf32-epiphany"
#define ELF_ARCH bfd_arch_epiphany
#define ELF_MACHINE_CODE EM_ADAPTEVA_EPIPHANY
#define ELF_MAXPAGESIZE 0x8000 /* No pages on the EPIPHANY. */
#define elf_info_to_howto_rel NULL
#define elf_info_to_howto epiphany_info_to_howto_rela
#define elf_backend_can_gc_sections 1
#define elf_backend_rela_normal 1
#define elf_backend_relocate_section epiphany_elf_relocate_section
#define elf_symbol_leading_char '_'
#define bfd_elf32_bfd_reloc_type_lookup epiphany_reloc_type_lookup
#define bfd_elf32_bfd_reloc_name_lookup epiphany_reloc_name_lookup
#define bfd_elf32_bfd_relax_section epiphany_elf_relax_section
#include "elf32-target.h"