binutils-gdb/bfd/elf32-openrisc.c
2001-04-24 15:08:16 +00:00

654 lines
19 KiB
C

/* OpenRISC-specific support for 32-bit ELF.
Copyright (C) 2001 Free Software Foundation, Inc.
Contributed by Johan Rydberg, jrydberg@opencores.org
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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "elf-bfd.h"
#include "elf/openrisc.h"
#include "libiberty.h"
/* Forward declarations. */
static reloc_howto_type *openrisc_reloc_type_lookup
PARAMS ((bfd * , bfd_reloc_code_real_type));
static void openrisc_info_to_howto_rela
PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
static boolean openrisc_elf_relocate_section
PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
static bfd_reloc_status_type openrisc_final_link_relocate
PARAMS ((reloc_howto_type *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, bfd_vma));
static boolean openrisc_elf_gc_sweep_hook
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
static asection *openrisc_elf_gc_mark_hook
PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
struct elf_link_hash_entry *, Elf_Internal_Sym *));
static reloc_howto_type openrisc_elf_howto_table[] =
{
/* This reloc does nothing. */
HOWTO (R_OPENRISC_NONE, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
32, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_NONE", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false), /* pcrel_offset */
/* A PC relative 26 bit relocation, right shifted by 2. */
HOWTO (R_OPENRISC_INSN_REL_26, /* type */
2, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
26, /* bitsize */
true, /* pc_relative */
0, /* bitpos */
complain_overflow_signed, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_INSN_REL_26", /* name */
false, /* partial_inplace */
0x00000000, /* src_mask */
0x03ffffff, /* dst_mask */
false), /* pcrel_offset */
/* A absolute 26 bit relocation, right shifted by 2. */
HOWTO (R_OPENRISC_INSN_ABS_26, /* type */
2, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
26, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_signed, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_INSN_ABS_26", /* name */
false, /* partial_inplace */
0x00000000, /* src_mask */
0x03ffffff, /* dst_mask */
false), /* pcrel_offset */
HOWTO (R_OPENRISC_LO_16_IN_INSN, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
16, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_LO_16_IN_INSN", /* name */
false, /* partial_inplace */
0x0000ffff, /* src_mask */
0x0000ffff, /* dst_mask */
false), /* pcrel_offset */
HOWTO (R_OPENRISC_HI_16_IN_INSN, /* type */
16, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
16, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_HI_16_IN_INSN", /* name */
false, /* partial_inplace */
0x0000ffff, /* src_mask */
0x0000ffff, /* dst_mask */
false), /* pcrel_offset */
/* An 8 bit absolute relocation. */
HOWTO (R_OPENRISC_8, /* type */
0, /* rightshift */
0, /* size (0 = byte, 1 = short, 2 = long) */
8, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_8", /* name */
true, /* partial_inplace */
0x0000, /* src_mask */
0x00ff, /* dst_mask */
false), /* pcrel_offset */
/* A 16 bit absolute relocation. */
HOWTO (R_OPENRISC_16, /* type */
0, /* rightshift */
1, /* size (0 = byte, 1 = short, 2 = long) */
16, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_16", /* name */
true, /* partial_inplace */
0x00000000, /* src_mask */
0x0000ffff, /* dst_mask */
false), /* pcrel_offset */
/* A 32 bit absolute relocation. */
HOWTO (R_OPENRISC_32, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
32, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_bitfield, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_OPENRISC_32", /* name */
true, /* partial_inplace */
0x00000000, /* src_mask */
0xffffffff, /* dst_mask */
false), /* pcrel_offset */
/* GNU extension to record C++ vtable hierarchy */
HOWTO (R_OPENRISC_GNU_VTINHERIT, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
0, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_dont, /* complain_on_overflow */
NULL, /* special_function */
"R_OPENRISC_GNU_VTINHERIT", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false), /* pcrel_offset */
/* GNU extension to record C++ vtable member usage */
HOWTO (R_OPENRISC_GNU_VTENTRY, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
0, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_dont, /* complain_on_overflow */
_bfd_elf_rel_vtable_reloc_fn, /* special_function */
"R_OPENRISC_GNU_VTENTRY", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false), /* pcrel_offset */
};
/* Map BFD reloc types to OpenRISC ELF reloc types. */
struct openrisc_reloc_map
{
bfd_reloc_code_real_type bfd_reloc_val;
unsigned int openrisc_reloc_val;
};
static const struct openrisc_reloc_map openrisc_reloc_map[] =
{
{ BFD_RELOC_NONE, R_OPENRISC_NONE },
{ BFD_RELOC_32, R_OPENRISC_32 },
{ BFD_RELOC_16, R_OPENRISC_16 },
{ BFD_RELOC_8, R_OPENRISC_8 },
{ BFD_RELOC_OPENRISC_REL_26,R_OPENRISC_INSN_REL_26 },
{ BFD_RELOC_OPENRISC_ABS_26,R_OPENRISC_INSN_ABS_26 },
{ BFD_RELOC_HI16, R_OPENRISC_HI_16_IN_INSN },
{ BFD_RELOC_LO16, R_OPENRISC_LO_16_IN_INSN },
{ BFD_RELOC_VTABLE_INHERIT, R_OPENRISC_GNU_VTINHERIT },
{ BFD_RELOC_VTABLE_ENTRY, R_OPENRISC_GNU_VTENTRY }
};
static reloc_howto_type *
openrisc_reloc_type_lookup (abfd, code)
bfd * abfd ATTRIBUTE_UNUSED;
bfd_reloc_code_real_type code;
{
unsigned int i;
for (i = ARRAY_SIZE (openrisc_reloc_map); --i;)
if (openrisc_reloc_map[i].bfd_reloc_val == code)
return & openrisc_elf_howto_table[openrisc_reloc_map[i].
openrisc_reloc_val];
return NULL;
}
/* Set the howto pointer for an OpenRISC ELF reloc. */
static void
openrisc_info_to_howto_rela (abfd, cache_ptr, dst)
bfd * abfd ATTRIBUTE_UNUSED;
arelent * cache_ptr;
Elf32_Internal_Rela * dst;
{
unsigned int r_type;
r_type = ELF32_R_TYPE (dst->r_info);
BFD_ASSERT (r_type < (unsigned int) R_OPENRISC_max);
cache_ptr->howto = & openrisc_elf_howto_table[r_type];
}
/* Perform a single relocation. By default we use the standard BFD
routines, but a few relocs, we have to do them ourselves. */
static bfd_reloc_status_type
openrisc_final_link_relocate (howto, input_bfd, input_section, contents, rel,
relocation)
reloc_howto_type *howto;
bfd *input_bfd;
asection *input_section;
bfd_byte *contents;
Elf_Internal_Rela *rel;
bfd_vma relocation;
{
bfd_reloc_status_type r = bfd_reloc_ok;
switch (howto->type)
{
case R_OPENRISC_LO_16_IN_INSN:
relocation &= 0xffff;
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, rel->r_addend);
break;
default:
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, rel->r_addend);
}
return r;
}
/* Relocate an OpenRISC ELF section.
There is some attempt to make this function usable for many architectures,
both USE_REL and USE_RELA ['twould be nice if such a critter existed],
if only to serve as a learning tool.
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 relocateable
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 relocateable 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 boolean
openrisc_elf_relocate_section (output_bfd, info, input_bfd, input_section,
contents, relocs, local_syms, local_sections)
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;
r_type = ELF32_R_TYPE (rel->r_info);
r_symndx = ELF32_R_SYM (rel->r_info);
if (r_type == R_OPENRISC_GNU_VTINHERIT
|| r_type == R_OPENRISC_GNU_VTENTRY)
continue;
if (info->relocateable)
{
/* This is a relocateable link. We don't have to change
anything, unless the reloc is against a section symbol,
in which case we have to adjust according to where the
section symbol winds up in the output section. */
if (r_symndx < symtab_hdr->sh_info)
{
sym = local_syms + r_symndx;
if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
{
sec = local_sections[r_symndx];
rel->r_addend += sec->output_offset + sym->st_value;
}
}
continue;
}
if ((unsigned int) r_type >
(sizeof openrisc_elf_howto_table / sizeof (reloc_howto_type)))
abort ();
/* This is a final link. */
howto = openrisc_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 = (sec->output_section->vma
+ sec->output_offset + 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
{
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
while (h->root.type == bfd_link_hash_indirect
|| h->root.type == bfd_link_hash_warning)
h = (struct elf_link_hash_entry *) h->root.u.i.link;
name = h->root.root.string;
if (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak)
{
sec = h->root.u.def.section;
relocation = (h->root.u.def.value
+ sec->output_section->vma + sec->output_offset);
}
else if (h->root.type == bfd_link_hash_undefweak)
{
relocation = 0;
}
else
{
if (!((*info->callbacks->undefined_symbol)
(info, h->root.root.string, input_bfd,
input_section, rel->r_offset, true)))
return false;
relocation = 0;
}
}
r = openrisc_final_link_relocate (howto, input_bfd, input_section,
contents, rel, relocation);
if (r != bfd_reloc_ok)
{
const char *msg = (const char *) NULL;
switch (r)
{
case bfd_reloc_overflow:
r = info->callbacks->reloc_overflow
(info, 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;
case bfd_reloc_notsupported:
msg = _("internal error: unsupported relocation error");
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;
}
/* Return the section that should be marked against GC for a given
relocation. */
static asection *
openrisc_elf_gc_mark_hook (abfd, info, rel, h, sym)
bfd *abfd ATTRIBUTE_UNUSED;
struct bfd_link_info *info ATTRIBUTE_UNUSED;
Elf_Internal_Rela *rel ATTRIBUTE_UNUSED;
struct elf_link_hash_entry *h ATTRIBUTE_UNUSED;
Elf_Internal_Sym *sym ATTRIBUTE_UNUSED;
{
if (h != NULL)
{
switch (ELF32_R_TYPE (rel->r_info))
{
case R_OPENRISC_GNU_VTINHERIT:
case R_OPENRISC_GNU_VTENTRY:
break;
default:
switch (h->root.type)
{
case bfd_link_hash_defined:
case bfd_link_hash_defweak:
return h->root.u.def.section;
case bfd_link_hash_common:
return h->root.u.c.p->section;
default:
break;
}
}
}
else
{
if (!(elf_bad_symtab (abfd)
&& ELF_ST_BIND (sym->st_info) != STB_LOCAL)
&& !((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
&& sym->st_shndx != SHN_COMMON))
{
return bfd_section_from_elf_index (abfd, sym->st_shndx);
}
}
return NULL;
}
/* Update the got entry reference counts for the section being removed. */
static boolean
openrisc_elf_gc_sweep_hook (abfd, info, sec, relocs)
bfd *abfd ATTRIBUTE_UNUSED;
struct bfd_link_info *info ATTRIBUTE_UNUSED;
asection *sec ATTRIBUTE_UNUSED;
const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
{
return true;
}
/* Look through the relocs for a section during the first phase.
Since we don't do .gots or .plts, we just need to consider the
virtual table relocs for gc. */
static boolean
openrisc_elf_check_relocs (abfd, info, sec, relocs)
bfd *abfd;
struct bfd_link_info *info;
asection *sec;
const Elf_Internal_Rela *relocs;
{
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
const Elf_Internal_Rela *rel;
const Elf_Internal_Rela *rel_end;
if (info->relocateable)
return true;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (abfd);
sym_hashes_end =
sym_hashes + symtab_hdr->sh_size / sizeof (Elf32_External_Sym);
if (!elf_bad_symtab (abfd))
sym_hashes_end -= symtab_hdr->sh_info;
rel_end = relocs + sec->reloc_count;
for (rel = relocs; rel < rel_end; rel++)
{
struct elf_link_hash_entry *h;
unsigned long r_symndx;
r_symndx = ELF32_R_SYM (rel->r_info);
if (r_symndx < symtab_hdr->sh_info)
h = NULL;
else
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
switch (ELF32_R_TYPE (rel->r_info))
{
/* This relocation describes the C++ object vtable hierarchy.
Reconstruct it for later use during GC. */
case R_OPENRISC_GNU_VTINHERIT:
if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
return false;
break;
/* This relocation describes which C++ vtable entries are actually
used. Record for later use during GC. */
case R_OPENRISC_GNU_VTENTRY:
if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
return false;
break;
}
}
return true;
}
/* Set the right machine number. */
static boolean
openrisc_elf_object_p (abfd)
bfd *abfd;
{
switch (elf_elfheader (abfd)->e_flags & 0xf)
{
default:
(void) bfd_default_set_arch_mach (abfd, bfd_arch_openrisc, 0);
break;
}
return true;
}
/* Store the machine number in the flags field. */
static void
openrisc_elf_final_write_processing (abfd, linker)
bfd *abfd;
boolean linker ATTRIBUTE_UNUSED;
{
unsigned long val;
switch (bfd_get_mach (abfd))
{
default:
val = 0;
break;
}
elf_elfheader (abfd)->e_flags &= ~0xf;
elf_elfheader (abfd)->e_flags |= val;
}
#define ELF_ARCH bfd_arch_openrisc
#define ELF_MACHINE_CODE EM_OPENRISC
#define ELF_MAXPAGESIZE 0x1000
#define TARGET_BIG_SYM bfd_elf32_openrisc_vec
#define TARGET_BIG_NAME "elf32-openrisc"
#define elf_info_to_howto_rel NULL
#define elf_info_to_howto openrisc_info_to_howto_rela
#define elf_backend_relocate_section openrisc_elf_relocate_section
#define elf_backend_gc_mark_hook openrisc_elf_gc_mark_hook
#define elf_backend_gc_sweep_hook openrisc_elf_gc_sweep_hook
#define elf_backend_check_relocs openrisc_elf_check_relocs
#define elf_backend_can_gc_sections 1
#define bfd_elf32_bfd_reloc_type_lookup openrisc_reloc_type_lookup
#define elf_backend_object_p openrisc_elf_object_p
#define elf_backend_final_write_processing openrisc_elf_final_write_processing
#include "elf32-target.h"