binutils-gdb/bfd/elf32-xstormy16.c

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/* XSTORMY16-specific support for 32-bit ELF.
Copyright (C) 2000, 2001 Free Software Foundation, 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 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/xstormy16.h"
/* Forward declarations. */
static reloc_howto_type * xstormy16_reloc_type_lookup
PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
static void xstormy16_info_to_howto_rela
PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
static bfd_reloc_status_type xstormy16_elf_24_reloc
PARAMS ((bfd *abfd, arelent *reloc_entry, asymbol *symbol,
PTR data, asection *input_section, bfd *output_bfd,
char **error_message));
static boolean xstormy16_elf_check_relocs
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
static boolean xstormy16_relax_plt_check
PARAMS ((struct elf_link_hash_entry *, PTR));
static boolean xstormy16_relax_plt_realloc
PARAMS ((struct elf_link_hash_entry *, PTR));
static boolean xstormy16_elf_relax_section
PARAMS ((bfd *abfd, asection *sec, struct bfd_link_info *link_info,
boolean *again));
static boolean xstormy16_elf_always_size_sections
PARAMS ((bfd *, struct bfd_link_info *));
static boolean xstormy16_elf_relocate_section
PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
static boolean xstormy16_elf_finish_dynamic_sections
PARAMS((bfd *, struct bfd_link_info *));
static boolean xstormy16_elf_gc_sweep_hook
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
static asection * xstormy16_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 xstormy16_elf_howto_table [] =
{
/* This reloc does nothing. */
HOWTO (R_XSTORMY16_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_XSTORMY16_NONE", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false), /* pcrel_offset */
/* A 32 bit absolute relocation. */
HOWTO (R_XSTORMY16_32, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
32, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_dont, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_XSTORMY16_32", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
false), /* pcrel_offset */
/* A 16 bit absolute relocation. */
HOWTO (R_XSTORMY16_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_XSTORMY16_16", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
false), /* pcrel_offset */
/* An 8 bit absolute relocation. */
HOWTO (R_XSTORMY16_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_XSTORMY16_8", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
false), /* pcrel_offset */
/* A 32 bit pc-relative relocation. */
HOWTO (R_XSTORMY16_PC32, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
32, /* bitsize */
true, /* pc_relative */
0, /* bitpos */
complain_overflow_dont, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_XSTORMY16_PC32", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
true), /* pcrel_offset */
/* A 16 bit pc-relative relocation. */
HOWTO (R_XSTORMY16_PC16, /* type */
0, /* rightshift */
1, /* size (0 = byte, 1 = short, 2 = long) */
16, /* bitsize */
true, /* pc_relative */
0, /* bitpos */
complain_overflow_signed, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_XSTORMY16_PC16", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
true), /* pcrel_offset */
/* An 8 bit pc-relative relocation. */
HOWTO (R_XSTORMY16_PC8, /* type */
0, /* rightshift */
0, /* size (0 = byte, 1 = short, 2 = long) */
8, /* bitsize */
true, /* pc_relative */
0, /* bitpos */
complain_overflow_signed, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_XSTORMY16_PC8", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
true), /* pcrel_offset */
/* A 12-bit pc-relative relocation suitable for the branch instructions. */
HOWTO (R_XSTORMY16_REL_12, /* type */
1, /* rightshift */
1, /* size (0 = byte, 1 = short, 2 = long) */
11, /* bitsize */
true, /* pc_relative */
1, /* bitpos */
complain_overflow_signed, /* complain_on_overflow */
bfd_elf_generic_reloc, /* special_function */
"R_XSTORMY16_REL_12", /* name */
true, /* partial_inplace */
0, /* src_mask */
0x0fff, /* dst_mask */
true), /* pcrel_offset */
/* A 24-bit absolute relocation suitable for the jump instructions. */
HOWTO (R_XSTORMY16_24, /* type */
0, /* rightshift */
2, /* size (0 = byte, 1 = short, 2 = long) */
24, /* bitsize */
false, /* pc_relative */
0, /* bitpos */
complain_overflow_unsigned, /* complain_on_overflow */
xstormy16_elf_24_reloc, /* special_function */
"R_XSTORMY16_24", /* name */
true, /* partial_inplace */
0, /* src_mask */
0xffff00ff, /* dst_mask */
true), /* pcrel_offset */
/* A 16 bit absolute relocation to a function pointer. */
HOWTO (R_XSTORMY16_FPTR16, /* 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_XSTORMY16_FPTR16", /* name */
false, /* partial_inplace */
0, /* src_mask */
0xffffffff, /* dst_mask */
false), /* pcrel_offset */
};
static reloc_howto_type xstormy16_elf_howto_table2 [] =
{
/* GNU extension to record C++ vtable hierarchy */
HOWTO (R_XSTORMY16_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_XSTORMY16_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_XSTORMY16_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_XSTORMY16_GNU_VTENTRY", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false), /* pcrel_offset */
};
/* Map BFD reloc types to XSTORMY16 ELF reloc types. */
struct xstormy16_reloc_map
{
bfd_reloc_code_real_type bfd_reloc_val;
unsigned int xstormy16_reloc_val;
};
static const struct xstormy16_reloc_map xstormy16_reloc_map [] =
{
{ BFD_RELOC_NONE, R_XSTORMY16_NONE },
{ BFD_RELOC_32, R_XSTORMY16_32 },
{ BFD_RELOC_16, R_XSTORMY16_16 },
{ BFD_RELOC_8, R_XSTORMY16_8 },
{ BFD_RELOC_32_PCREL, R_XSTORMY16_PC32 },
{ BFD_RELOC_16_PCREL, R_XSTORMY16_PC16 },
{ BFD_RELOC_8_PCREL, R_XSTORMY16_PC8 },
{ BFD_RELOC_XSTORMY16_REL_12, R_XSTORMY16_REL_12 },
{ BFD_RELOC_XSTORMY16_24, R_XSTORMY16_24 },
{ BFD_RELOC_XSTORMY16_FPTR16, R_XSTORMY16_FPTR16 },
{ BFD_RELOC_VTABLE_INHERIT, R_XSTORMY16_GNU_VTINHERIT },
{ BFD_RELOC_VTABLE_ENTRY, R_XSTORMY16_GNU_VTENTRY },
};
static reloc_howto_type *
xstormy16_reloc_type_lookup (abfd, code)
bfd * abfd ATTRIBUTE_UNUSED;
bfd_reloc_code_real_type code;
{
unsigned int i;
for (i = sizeof (xstormy16_reloc_map) / sizeof (xstormy16_reloc_map[0]);
--i;)
if (xstormy16_reloc_map [i].bfd_reloc_val == code)
return & xstormy16_elf_howto_table [xstormy16_reloc_map[i].xstormy16_reloc_val];
return NULL;
}
/* Set the howto pointer for an XSTORMY16 ELF reloc. */
static void
xstormy16_info_to_howto_rela (abfd, cache_ptr, dst)
bfd * abfd ATTRIBUTE_UNUSED;
arelent * cache_ptr;
Elf32_Internal_Rela * dst;
{
unsigned int r_type = ELF32_R_TYPE (dst->r_info);
if (r_type <= (unsigned int) R_XSTORMY16_FPTR16)
cache_ptr->howto = &xstormy16_elf_howto_table [r_type];
else if (r_type - R_XSTORMY16_GNU_VTINHERIT
<= (unsigned int) R_XSTORMY16_GNU_VTENTRY)
cache_ptr->howto
= &xstormy16_elf_howto_table2 [r_type - R_XSTORMY16_GNU_VTINHERIT];
else
abort ();
}
/* Handle the R_XSTORMY16_24 reloc, which has an odd bit arrangement. */
static bfd_reloc_status_type
xstormy16_elf_24_reloc (abfd, reloc_entry, symbol, data, input_section,
output_bfd, error_message)
bfd *abfd;
arelent *reloc_entry;
asymbol *symbol;
PTR data;
asection *input_section;
bfd *output_bfd;
char **error_message ATTRIBUTE_UNUSED;
{
bfd_vma relocation, x;
if (output_bfd != NULL)
{
reloc_entry->address += input_section->output_offset;
return bfd_reloc_ok;
}
if (reloc_entry->address > input_section->_cooked_size)
return bfd_reloc_outofrange;
if (bfd_is_com_section (symbol->section))
relocation = 0;
else
relocation = symbol->value;
relocation += symbol->section->output_section->vma;
relocation += symbol->section->output_offset;
relocation += reloc_entry->addend;
x = bfd_get_32 (abfd, (bfd_byte *) data + reloc_entry->address);
x &= 0x0000ff00;
x |= relocation & 0xff;
x |= (relocation << 8) & 0xffff0000;
bfd_put_32 (abfd, x, (bfd_byte *) data + reloc_entry->address);
if (relocation & ~ (bfd_vma) 0xffffff)
return bfd_reloc_overflow;
return bfd_reloc_ok;
}
/* We support 16-bit pointers to code above 64k by generating a thunk
below 64k containing a JMPF instruction to the final address. We
cannot, unfortunately, minimize the number of thunks unless the
-relax switch is given, as otherwise we have no idea where the
sections will fall in the address space. */
static boolean
xstormy16_elf_check_relocs (abfd, info, sec, relocs)
bfd *abfd;
struct bfd_link_info *info;
asection *sec;
const Elf_Internal_Rela *relocs;
{
const Elf_Internal_Rela *rel, *relend;
struct elf_link_hash_entry **sym_hashes;
Elf_Internal_Shdr *symtab_hdr;
bfd_vma *local_plt_offsets;
asection *splt;
bfd *dynobj;
if (info->relocateable)
return true;
symtab_hdr = &elf_tdata(abfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (abfd);
local_plt_offsets = elf_local_got_offsets (abfd);
splt = NULL;
dynobj = elf_hash_table(info)->dynobj;
relend = relocs + sec->reloc_count;
for (rel = relocs; rel < relend; ++rel)
{
unsigned long r_symndx;
struct elf_link_hash_entry *h;
bfd_vma *offset;
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];
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;
}
switch (ELF32_R_TYPE (rel->r_info))
{
/* This relocation describes a 16-bit pointer to a function.
We may need to allocate a thunk in low memory; reserve memory
for it now. */
case R_XSTORMY16_FPTR16:
if (rel->r_addend != 0)
{
(*info->callbacks->warning)
(info, _("non-zero addend in @fptr reloc"), 0,
abfd, 0, 0);
}
if (dynobj == NULL)
elf_hash_table (info)->dynobj = dynobj = abfd;
if (splt == NULL)
{
splt = bfd_get_section_by_name (dynobj, ".plt");
if (splt == NULL)
{
splt = bfd_make_section (dynobj, ".plt");
if (splt == NULL
|| ! bfd_set_section_flags (dynobj, splt,
(SEC_ALLOC
| SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_IN_MEMORY
| SEC_LINKER_CREATED
| SEC_READONLY
| SEC_CODE))
|| ! bfd_set_section_alignment (dynobj, splt, 1))
return false;
}
}
if (h != NULL)
offset = &h->plt.offset;
else
{
if (local_plt_offsets == NULL)
{
size_t size;
unsigned int i;
size = symtab_hdr->sh_info * sizeof (bfd_vma);
local_plt_offsets = (bfd_vma *) bfd_alloc (abfd, size);
if (local_plt_offsets == NULL)
return false;
elf_local_got_offsets (abfd) = local_plt_offsets;
for (i = 0; i < symtab_hdr->sh_info; i++)
local_plt_offsets[i] = (bfd_vma) -1;
}
offset = &local_plt_offsets[r_symndx];
}
if (*offset == (bfd_vma) -1)
{
*offset = splt->_raw_size;
splt->_raw_size += 4;
}
break;
/* This relocation describes the C++ object vtable hierarchy.
Reconstruct it for later use during GC. */
case R_XSTORMY16_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_XSTORMY16_GNU_VTENTRY:
if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
return false;
break;
}
}
return true;
}
/* A subroutine of xstormy16_elf_relax_section. If the global symbol H
is within the low 64k, remove any entry for it in the plt. */
struct relax_plt_data
{
asection *splt;
boolean *again;
};
static boolean
xstormy16_relax_plt_check (h, xdata)
struct elf_link_hash_entry *h;
PTR xdata;
{
struct relax_plt_data *data = (struct relax_plt_data *) xdata;
if (h->plt.offset != (bfd_vma) -1)
{
bfd_vma address;
if (h->root.type == bfd_link_hash_undefined
|| h->root.type == bfd_link_hash_undefweak)
address = 0;
else
address = (h->root.u.def.section->output_section->vma
+ h->root.u.def.section->output_offset
+ h->root.u.def.value);
if (address <= 0xffff)
{
h->plt.offset = -1;
data->splt->_cooked_size -= 4;
*data->again = true;
}
}
return true;
}
/* A subroutine of xstormy16_elf_relax_section. If the global symbol H
previously had a plt entry, give it a new entry offset. */
static boolean
xstormy16_relax_plt_realloc (h, xdata)
struct elf_link_hash_entry *h;
PTR xdata;
{
bfd_vma *entry = (bfd_vma *) xdata;
if (h->plt.offset != (bfd_vma) -1)
{
h->plt.offset = *entry;
*entry += 4;
}
return true;
}
static boolean
xstormy16_elf_relax_section (dynobj, splt, info, again)
bfd *dynobj;
asection *splt;
struct bfd_link_info *info;
boolean *again;
{
struct relax_plt_data relax_plt_data;
bfd *ibfd;
/* Assume nothing changes. */
*again = false;
if (info->relocateable)
return true;
/* We only relax the .plt section at the moment. */
if (dynobj != elf_hash_table (info)->dynobj
|| strcmp (splt->name, ".plt") != 0)
return true;
/* Quick check for an empty plt. */
if (splt->_raw_size == 0)
return true;
/* If this is the first time we have been called for this section,
initialize the cooked size. */
if (splt->_cooked_size == 0)
splt->_cooked_size = splt->_raw_size;
/* Map across all global symbols; see which ones happen to
fall in the low 64k. */
relax_plt_data.splt = splt;
relax_plt_data.again = again;
elf_link_hash_traverse (elf_hash_table (info), xstormy16_relax_plt_check,
&relax_plt_data);
/* Likewise for local symbols, though that's somewhat less convenient
as we have walk the list of input bfds and swap in symbol data. */
for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link_next)
{
bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
Elf_Internal_Shdr *symtab_hdr;
Elf_Internal_Shdr *shndx_hdr;
Elf32_External_Sym *extsyms;
Elf_External_Sym_Shndx *shndx_buf;
unsigned int idx;
if (! local_plt_offsets)
continue;
symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
shndx_hdr = &elf_tdata (ibfd)->symtab_shndx_hdr;
if (symtab_hdr->contents != NULL)
extsyms = (Elf32_External_Sym *) symtab_hdr->contents;
else
{
bfd_size_type amt;
amt = symtab_hdr->sh_info;
amt *= sizeof (Elf32_External_Sym);
extsyms = (Elf32_External_Sym *) bfd_malloc (amt);
if (extsyms == NULL)
return false;
if (bfd_seek (ibfd, symtab_hdr->sh_offset, SEEK_SET) != 0
|| bfd_bread ((PTR) extsyms, amt, ibfd) != amt)
{
error_ret_free_extsyms:
free (extsyms);
return false;
}
}
shndx_buf = NULL;
if (shndx_hdr->sh_size != 0)
{
bfd_size_type amt;
amt = symtab_hdr->sh_info;
amt *= sizeof (Elf_External_Sym_Shndx);
shndx_buf = (Elf_External_Sym_Shndx *) bfd_malloc (amt);
if (shndx_buf == NULL)
goto error_ret_free_extsyms;
if (bfd_seek (ibfd, shndx_hdr->sh_offset, SEEK_SET) != 0
|| bfd_bread ((PTR) shndx_buf, amt, ibfd) != amt)
{
free (shndx_buf);
goto error_ret_free_extsyms;
}
shndx_hdr->contents = (bfd_byte *) shndx_buf;
}
for (idx = 0; idx < symtab_hdr->sh_info; ++idx)
{
Elf_External_Sym_Shndx *shndx;
Elf_Internal_Sym isym;
asection *tsec;
bfd_vma address;
if (local_plt_offsets[idx] == (bfd_vma) -1)
continue;
shndx = shndx_buf;
if (shndx != NULL)
shndx += idx;
bfd_elf32_swap_symbol_in (ibfd, extsyms + idx, shndx, &isym);
if (isym.st_shndx == SHN_UNDEF)
continue;
else if (isym.st_shndx == SHN_ABS)
tsec = bfd_abs_section_ptr;
else if (isym.st_shndx == SHN_COMMON)
tsec = bfd_com_section_ptr;
else
tsec = bfd_section_from_elf_index (ibfd, isym.st_shndx);
address = (tsec->output_section->vma
+ tsec->output_offset
+ isym.st_value);
if (address <= 0xffff)
{
local_plt_offsets[idx] = -1;
splt->_cooked_size -= 4;
*again = true;
}
}
if (shndx_buf != NULL)
free (shndx_buf);
if ((Elf32_External_Sym *) symtab_hdr->contents != extsyms)
free (extsyms);
}
/* If we changed anything, walk the symbols again to reallocate
.plt entry addresses. */
if (*again && splt->_cooked_size > 0)
{
bfd_vma entry = 0;
elf_link_hash_traverse (elf_hash_table (info),
xstormy16_relax_plt_realloc, &entry);
for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link_next)
{
bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
unsigned int nlocals = elf_tdata (ibfd)->symtab_hdr.sh_info;
unsigned int idx;
if (! local_plt_offsets)
continue;
for (idx = 0; idx < nlocals; ++idx)
if (local_plt_offsets[idx] != (bfd_vma) -1)
{
local_plt_offsets[idx] = entry;
entry += 4;
}
}
}
splt->_raw_size = splt->_cooked_size;
return true;
}
static boolean
xstormy16_elf_always_size_sections (output_bfd, info)
bfd *output_bfd ATTRIBUTE_UNUSED;
struct bfd_link_info *info;
{
bfd *dynobj;
asection *splt;
if (info->relocateable)
return true;
dynobj = elf_hash_table (info)->dynobj;
if (dynobj == NULL)
return true;
splt = bfd_get_section_by_name (dynobj, ".plt");
BFD_ASSERT (splt != NULL);
splt->contents = (bfd_byte *) bfd_zalloc (dynobj, splt->_raw_size);
if (splt->contents == NULL)
return false;
return true;
}
/* Relocate an XSTORMY16 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
xstormy16_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;
bfd *dynobj;
asection *splt;
symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (input_bfd);
relend = relocs + input_section->reloc_count;
dynobj = elf_hash_table (info)->dynobj;
splt = NULL;
if (dynobj != NULL)
splt = bfd_get_section_by_name (dynobj, ".plt");
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);
if ( r_type == R_XSTORMY16_GNU_VTINHERIT
|| r_type == R_XSTORMY16_GNU_VTENTRY)
continue;
r_symndx = ELF32_R_SYM (rel->r_info);
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;
}
/* This is a final link. */
howto = xstormy16_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;
}
}
switch (ELF32_R_TYPE (rel->r_info))
{
case R_XSTORMY16_24:
{
bfd_vma reloc = relocation + rel->r_addend;
unsigned int x;
x = bfd_get_32 (input_bfd, contents + rel->r_offset);
x &= 0x0000ff00;
x |= reloc & 0xff;
x |= (reloc << 8) & 0xffff0000;
bfd_put_32 (input_bfd, x, contents + rel->r_offset);
if (reloc & ~0xffffff)
r = bfd_reloc_overflow;
else
r = bfd_reloc_ok;
break;
}
case R_XSTORMY16_FPTR16:
{
bfd_vma *plt_offset;
if (h != NULL)
plt_offset = &h->plt.offset;
else
plt_offset = elf_local_got_offsets (input_bfd) + r_symndx;
if (relocation <= 0xffff)
{
/* If the symbol is in range for a 16-bit address, we should
have deallocated the plt entry in relax_section. */
BFD_ASSERT (*plt_offset == (bfd_vma) -1);
}
else
{
/* If the symbol is out of range for a 16-bit address,
we must have allocated a plt entry. */
BFD_ASSERT (*plt_offset != (bfd_vma) -1);
/* If this is the first time we've processed this symbol,
fill in the plt entry with the correct symbol address. */
if ((*plt_offset & 1) == 0)
{
unsigned int x;
x = 0x00000200; /* jmpf */
x |= relocation & 0xff;
x |= (relocation << 8) & 0xffff0000;
bfd_put_32 (input_bfd, x, splt->contents + *plt_offset);
*plt_offset |= 1;
}
relocation = (splt->output_section->vma
+ splt->output_offset
+ (*plt_offset & -2));
}
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, 0);
break;
}
default:
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, rel->r_addend);
break;
}
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;
}
/* This must exist if dynobj is ever set. */
static boolean
xstormy16_elf_finish_dynamic_sections (abfd, info)
bfd *abfd ATTRIBUTE_UNUSED;
struct bfd_link_info *info;
{
bfd *dynobj;
asection *splt;
/* As an extra sanity check, verify that all plt entries have
been filled in. */
if ((dynobj = elf_hash_table (info)->dynobj) != NULL
&& (splt = bfd_get_section_by_name (dynobj, ".plt")) != NULL)
{
bfd_byte *contents = splt->contents;
unsigned int i, size = splt->_raw_size;
for (i = 0; i < size; i += 4)
{
unsigned int x = bfd_get_32 (dynobj, contents + i);
BFD_ASSERT (x != 0);
}
}
return true;
}
/* Return the section that should be marked against GC for a given
relocation. */
static asection *
xstormy16_elf_gc_mark_hook (abfd, info, rel, h, sym)
bfd * abfd;
struct bfd_link_info * info ATTRIBUTE_UNUSED;
Elf_Internal_Rela * rel;
struct elf_link_hash_entry * h;
Elf_Internal_Sym * sym;
{
if (h != NULL)
{
switch (ELF32_R_TYPE (rel->r_info))
{
case R_XSTORMY16_GNU_VTINHERIT:
case R_XSTORMY16_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
{
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
xstormy16_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;
}
#define ELF_ARCH bfd_arch_xstormy16
#define ELF_MACHINE_CODE EM_XSTORMY16
#define ELF_MAXPAGESIZE 0x100
#define TARGET_LITTLE_SYM bfd_elf32_xstormy16_vec
#define TARGET_LITTLE_NAME "elf32-xstormy16"
#define elf_info_to_howto_rel NULL
#define elf_info_to_howto xstormy16_info_to_howto_rela
#define elf_backend_relocate_section xstormy16_elf_relocate_section
#define elf_backend_gc_mark_hook xstormy16_elf_gc_mark_hook
#define elf_backend_gc_sweep_hook xstormy16_elf_gc_sweep_hook
#define elf_backend_check_relocs xstormy16_elf_check_relocs
#define elf_backend_always_size_sections \
xstormy16_elf_always_size_sections
#define elf_backend_finish_dynamic_sections \
xstormy16_elf_finish_dynamic_sections
#define elf_backend_can_gc_sections 1
#define bfd_elf32_bfd_reloc_type_lookup xstormy16_reloc_type_lookup
#define bfd_elf32_bfd_relax_section xstormy16_elf_relax_section
#include "elf32-target.h"