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binutils-gdb/bfd/elf32-m68k.c
Alan Modra dd5724d523 Reference count .plt and .got on x86 for garbage collection code. Fix a 
couple of m68k and ppc bugs discovered while testing x86 gc.
2000-04-27 00:31:17 +00:00

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/* Motorola 68k series support for 32-bit ELF
Copyright 1993, 95, 96, 97, 98, 1999 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 "bfdlink.h"
#include "libbfd.h"
#include "elf-bfd.h"
#include "elf/m68k.h"
static reloc_howto_type *reloc_type_lookup
PARAMS ((bfd *, bfd_reloc_code_real_type));
static void rtype_to_howto
PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
static struct bfd_hash_entry *elf_m68k_link_hash_newfunc
PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
static struct bfd_link_hash_table *elf_m68k_link_hash_table_create
PARAMS ((bfd *));
static boolean elf_m68k_check_relocs
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
static asection *elf_m68k_gc_mark_hook
PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
struct elf_link_hash_entry *, Elf_Internal_Sym *));
static boolean elf_m68k_gc_sweep_hook
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
static boolean elf_m68k_adjust_dynamic_symbol
PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
static boolean elf_m68k_size_dynamic_sections
PARAMS ((bfd *, struct bfd_link_info *));
static boolean elf_m68k_relocate_section
PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
static boolean elf_m68k_finish_dynamic_symbol
PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
Elf_Internal_Sym *));
static boolean elf_m68k_finish_dynamic_sections
PARAMS ((bfd *, struct bfd_link_info *));
static boolean elf32_m68k_set_private_flags
PARAMS ((bfd *, flagword));
static boolean elf32_m68k_copy_private_bfd_data
PARAMS ((bfd *, bfd *));
static boolean elf32_m68k_merge_private_bfd_data
PARAMS ((bfd *, bfd *));
static boolean elf32_m68k_print_private_bfd_data
PARAMS ((bfd *, PTR));
static reloc_howto_type howto_table[] = {
HOWTO(R_68K_NONE, 0, 0, 0, false,0, complain_overflow_dont, bfd_elf_generic_reloc, "R_68K_NONE", false, 0, 0x00000000,false),
HOWTO(R_68K_32, 0, 2,32, false,0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_32", false, 0, 0xffffffff,false),
HOWTO(R_68K_16, 0, 1,16, false,0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_16", false, 0, 0x0000ffff,false),
HOWTO(R_68K_8, 0, 0, 8, false,0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_8", false, 0, 0x000000ff,false),
HOWTO(R_68K_PC32, 0, 2,32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_PC32", false, 0, 0xffffffff,true),
HOWTO(R_68K_PC16, 0, 1,16, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PC16", false, 0, 0x0000ffff,true),
HOWTO(R_68K_PC8, 0, 0, 8, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PC8", false, 0, 0x000000ff,true),
HOWTO(R_68K_GOT32, 0, 2,32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_GOT32", false, 0, 0xffffffff,true),
HOWTO(R_68K_GOT16, 0, 1,16, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_GOT16", false, 0, 0x0000ffff,true),
HOWTO(R_68K_GOT8, 0, 0, 8, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_GOT8", false, 0, 0x000000ff,true),
HOWTO(R_68K_GOT32O, 0, 2,32, false,0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_GOT32O", false, 0, 0xffffffff,false),
HOWTO(R_68K_GOT16O, 0, 1,16, false,0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_GOT16O", false, 0, 0x0000ffff,false),
HOWTO(R_68K_GOT8O, 0, 0, 8, false,0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_GOT8O", false, 0, 0x000000ff,false),
HOWTO(R_68K_PLT32, 0, 2,32, true, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_PLT32", false, 0, 0xffffffff,true),
HOWTO(R_68K_PLT16, 0, 1,16, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PLT16", false, 0, 0x0000ffff,true),
HOWTO(R_68K_PLT8, 0, 0, 8, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PLT8", false, 0, 0x000000ff,true),
HOWTO(R_68K_PLT32O, 0, 2,32, false,0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_68K_PLT32O", false, 0, 0xffffffff,false),
HOWTO(R_68K_PLT16O, 0, 1,16, false,0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PLT16O", false, 0, 0x0000ffff,false),
HOWTO(R_68K_PLT8O, 0, 0, 8, false,0, complain_overflow_signed, bfd_elf_generic_reloc, "R_68K_PLT8O", false, 0, 0x000000ff,false),
HOWTO(R_68K_COPY, 0, 0, 0, false,0, complain_overflow_dont, bfd_elf_generic_reloc, "R_68K_COPY", false, 0, 0xffffffff,false),
HOWTO(R_68K_GLOB_DAT, 0, 2,32, false,0, complain_overflow_dont, bfd_elf_generic_reloc, "R_68K_GLOB_DAT", false, 0, 0xffffffff,false),
HOWTO(R_68K_JMP_SLOT, 0, 2,32, false,0, complain_overflow_dont, bfd_elf_generic_reloc, "R_68K_JMP_SLOT", false, 0, 0xffffffff,false),
HOWTO(R_68K_RELATIVE, 0, 2,32, false,0, complain_overflow_dont, bfd_elf_generic_reloc, "R_68K_RELATIVE", false, 0, 0xffffffff,false),
/* GNU extension to record C++ vtable hierarchy */
HOWTO (R_68K_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_68K_GNU_VTINHERIT", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false),
/* GNU extension to record C++ vtable member usage */
HOWTO (R_68K_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_68K_GNU_VTENTRY", /* name */
false, /* partial_inplace */
0, /* src_mask */
0, /* dst_mask */
false),
};
static void
rtype_to_howto (abfd, cache_ptr, dst)
bfd *abfd ATTRIBUTE_UNUSED;
arelent *cache_ptr;
Elf_Internal_Rela *dst;
{
BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_68K_max);
cache_ptr->howto = &howto_table[ELF32_R_TYPE(dst->r_info)];
}
#define elf_info_to_howto rtype_to_howto
static const struct
{
bfd_reloc_code_real_type bfd_val;
int elf_val;
} reloc_map[] = {
{ BFD_RELOC_NONE, R_68K_NONE },
{ BFD_RELOC_32, R_68K_32 },
{ BFD_RELOC_16, R_68K_16 },
{ BFD_RELOC_8, R_68K_8 },
{ BFD_RELOC_32_PCREL, R_68K_PC32 },
{ BFD_RELOC_16_PCREL, R_68K_PC16 },
{ BFD_RELOC_8_PCREL, R_68K_PC8 },
{ BFD_RELOC_32_GOT_PCREL, R_68K_GOT32 },
{ BFD_RELOC_16_GOT_PCREL, R_68K_GOT16 },
{ BFD_RELOC_8_GOT_PCREL, R_68K_GOT8 },
{ BFD_RELOC_32_GOTOFF, R_68K_GOT32O },
{ BFD_RELOC_16_GOTOFF, R_68K_GOT16O },
{ BFD_RELOC_8_GOTOFF, R_68K_GOT8O },
{ BFD_RELOC_32_PLT_PCREL, R_68K_PLT32 },
{ BFD_RELOC_16_PLT_PCREL, R_68K_PLT16 },
{ BFD_RELOC_8_PLT_PCREL, R_68K_PLT8 },
{ BFD_RELOC_32_PLTOFF, R_68K_PLT32O },
{ BFD_RELOC_16_PLTOFF, R_68K_PLT16O },
{ BFD_RELOC_8_PLTOFF, R_68K_PLT8O },
{ BFD_RELOC_NONE, R_68K_COPY },
{ BFD_RELOC_68K_GLOB_DAT, R_68K_GLOB_DAT },
{ BFD_RELOC_68K_JMP_SLOT, R_68K_JMP_SLOT },
{ BFD_RELOC_68K_RELATIVE, R_68K_RELATIVE },
{ BFD_RELOC_CTOR, R_68K_32 },
{ BFD_RELOC_VTABLE_INHERIT, R_68K_GNU_VTINHERIT },
{ BFD_RELOC_VTABLE_ENTRY, R_68K_GNU_VTENTRY },
};
static reloc_howto_type *
reloc_type_lookup (abfd, code)
bfd *abfd ATTRIBUTE_UNUSED;
bfd_reloc_code_real_type code;
{
unsigned int i;
for (i = 0; i < sizeof (reloc_map) / sizeof (reloc_map[0]); i++)
{
if (reloc_map[i].bfd_val == code)
return &howto_table[reloc_map[i].elf_val];
}
return 0;
}
#define bfd_elf32_bfd_reloc_type_lookup reloc_type_lookup
#define ELF_ARCH bfd_arch_m68k
/* end code generated by elf.el */
#define USE_RELA
/* Functions for the m68k ELF linker. */
/* The name of the dynamic interpreter. This is put in the .interp
section. */
#define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
/* The size in bytes of an entry in the procedure linkage table. */
#define PLT_ENTRY_SIZE 20
/* The first entry in a procedure linkage table looks like this. See
the SVR4 ABI m68k supplement to see how this works. */
static const bfd_byte elf_m68k_plt0_entry[PLT_ENTRY_SIZE] =
{
0x2f, 0x3b, 0x01, 0x70, /* move.l (%pc,addr),-(%sp) */
0, 0, 0, 0, /* replaced with offset to .got + 4. */
0x4e, 0xfb, 0x01, 0x71, /* jmp ([%pc,addr]) */
0, 0, 0, 0, /* replaced with offset to .got + 8. */
0, 0, 0, 0 /* pad out to 20 bytes. */
};
/* Subsequent entries in a procedure linkage table look like this. */
static const bfd_byte elf_m68k_plt_entry[PLT_ENTRY_SIZE] =
{
0x4e, 0xfb, 0x01, 0x71, /* jmp ([%pc,symbol@GOTPC]) */
0, 0, 0, 0, /* replaced with offset to symbol's .got entry. */
0x2f, 0x3c, /* move.l #offset,-(%sp) */
0, 0, 0, 0, /* replaced with offset into relocation table. */
0x60, 0xff, /* bra.l .plt */
0, 0, 0, 0 /* replaced with offset to start of .plt. */
};
#define CPU32_FLAG(abfd) (elf_elfheader (abfd)->e_flags & EF_CPU32)
#define PLT_CPU32_ENTRY_SIZE 24
/* Procedure linkage table entries for the cpu32 */
static const bfd_byte elf_cpu32_plt0_entry[PLT_CPU32_ENTRY_SIZE] =
{
0x22, 0x7b, 0x01, 0x70, /* moveal %pc@(0xc), %a1 */
0, 0, 0, 0, /* replaced with offset to .got + 4. */
0x4e, 0xd1, /* jmp %a1@ */
0, 0, 0, 0, /* replace with offset to .got +8. */
0, 0, 0, 0, /* pad out to 24 bytes. */
0, 0, 0, 0, /* pad out to 24 bytes. */
0, 0
};
static const bfd_byte elf_cpu32_plt_entry[PLT_CPU32_ENTRY_SIZE] =
{
0x22, 0x7b, 0x01, 0x70, /* moveal %pc@(0xc), %a1 */
0, 0, 0, 0, /* replaced with offset to symbol's .got entry. */
0x4e, 0xd1, /* jmp %a1@ */
0x2f, 0x3c, /* move.l #offset,-(%sp) */
0, 0, 0, 0, /* replaced with offset into relocation table. */
0x60, 0xff, /* bra.l .plt */
0, 0, 0, 0, /* replaced with offset to start of .plt. */
0, 0
};
/* The m68k linker needs to keep track of the number of relocs that it
decides to copy in check_relocs for each symbol. This is so that it
can discard PC relative relocs if it doesn't need them when linking
with -Bsymbolic. We store the information in a field extending the
regular ELF linker hash table. */
/* This structure keeps track of the number of PC relative relocs we have
copied for a given symbol. */
struct elf_m68k_pcrel_relocs_copied
{
/* Next section. */
struct elf_m68k_pcrel_relocs_copied *next;
/* A section in dynobj. */
asection *section;
/* Number of relocs copied in this section. */
bfd_size_type count;
};
/* m68k ELF linker hash entry. */
struct elf_m68k_link_hash_entry
{
struct elf_link_hash_entry root;
/* Number of PC relative relocs copied for this symbol. */
struct elf_m68k_pcrel_relocs_copied *pcrel_relocs_copied;
};
/* m68k ELF linker hash table. */
struct elf_m68k_link_hash_table
{
struct elf_link_hash_table root;
};
/* Declare this now that the above structures are defined. */
static boolean elf_m68k_discard_copies
PARAMS ((struct elf_m68k_link_hash_entry *, PTR));
/* Traverse an m68k ELF linker hash table. */
#define elf_m68k_link_hash_traverse(table, func, info) \
(elf_link_hash_traverse \
(&(table)->root, \
(boolean (*) PARAMS ((struct elf_link_hash_entry *, PTR))) (func), \
(info)))
/* Get the m68k ELF linker hash table from a link_info structure. */
#define elf_m68k_hash_table(p) \
((struct elf_m68k_link_hash_table *) (p)->hash)
/* Create an entry in an m68k ELF linker hash table. */
static struct bfd_hash_entry *
elf_m68k_link_hash_newfunc (entry, table, string)
struct bfd_hash_entry *entry;
struct bfd_hash_table *table;
const char *string;
{
struct elf_m68k_link_hash_entry *ret =
(struct elf_m68k_link_hash_entry *) entry;
/* Allocate the structure if it has not already been allocated by a
subclass. */
if (ret == (struct elf_m68k_link_hash_entry *) NULL)
ret = ((struct elf_m68k_link_hash_entry *)
bfd_hash_allocate (table,
sizeof (struct elf_m68k_link_hash_entry)));
if (ret == (struct elf_m68k_link_hash_entry *) NULL)
return (struct bfd_hash_entry *) ret;
/* Call the allocation method of the superclass. */
ret = ((struct elf_m68k_link_hash_entry *)
_bfd_elf_link_hash_newfunc ((struct bfd_hash_entry *) ret,
table, string));
if (ret != (struct elf_m68k_link_hash_entry *) NULL)
{
ret->pcrel_relocs_copied = NULL;
}
return (struct bfd_hash_entry *) ret;
}
/* Create an m68k ELF linker hash table. */
static struct bfd_link_hash_table *
elf_m68k_link_hash_table_create (abfd)
bfd *abfd;
{
struct elf_m68k_link_hash_table *ret;
ret = ((struct elf_m68k_link_hash_table *)
bfd_alloc (abfd, sizeof (struct elf_m68k_link_hash_table)));
if (ret == (struct elf_m68k_link_hash_table *) NULL)
return NULL;
if (! _bfd_elf_link_hash_table_init (&ret->root, abfd,
elf_m68k_link_hash_newfunc))
{
bfd_release (abfd, ret);
return NULL;
}
return &ret->root.root;
}
/* Keep m68k-specific flags in the ELF header */
static boolean
elf32_m68k_set_private_flags (abfd, flags)
bfd *abfd;
flagword flags;
{
elf_elfheader (abfd)->e_flags = flags;
elf_flags_init (abfd) = true;
return true;
}
/* Copy m68k-specific data from one module to another */
static boolean
elf32_m68k_copy_private_bfd_data (ibfd, obfd)
bfd *ibfd;
bfd *obfd;
{
flagword in_flags;
if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
|| bfd_get_flavour (obfd) != bfd_target_elf_flavour)
return true;
in_flags = elf_elfheader (ibfd)->e_flags;
elf_elfheader (obfd)->e_flags = in_flags;
elf_flags_init (obfd) = true;
return true;
}
/* Merge backend specific data from an object file to the output
object file when linking. */
static boolean
elf32_m68k_merge_private_bfd_data (ibfd, obfd)
bfd *ibfd;
bfd *obfd;
{
flagword out_flags;
flagword in_flags;
if ( bfd_get_flavour (ibfd) != bfd_target_elf_flavour
|| bfd_get_flavour (obfd) != bfd_target_elf_flavour)
return true;
in_flags = elf_elfheader (ibfd)->e_flags;
out_flags = elf_elfheader (obfd)->e_flags;
if (!elf_flags_init (obfd))
{
elf_flags_init (obfd) = true;
elf_elfheader (obfd)->e_flags = in_flags;
}
return true;
}
/* Display the flags field */
static boolean
elf32_m68k_print_private_bfd_data (abfd, ptr)
bfd *abfd;
PTR ptr;
{
FILE *file = (FILE *) ptr;
BFD_ASSERT (abfd != NULL && ptr != NULL);
/* Print normal ELF private data. */
_bfd_elf_print_private_bfd_data (abfd, ptr);
/* Ignore init flag - it may not be set, despite the flags field containing valid data. */
/* xgettext:c-format */
fprintf (file, _ ("private flags = %lx:"), elf_elfheader (abfd)->e_flags);
if (elf_elfheader (abfd)->e_flags & EF_CPU32)
fprintf (file, _ (" [cpu32]"));
fputc ('\n', file);
return true;
}
/* Look through the relocs for a section during the first phase, and
allocate space in the global offset table or procedure linkage
table. */
static boolean
elf_m68k_check_relocs (abfd, info, sec, relocs)
bfd *abfd;
struct bfd_link_info *info;
asection *sec;
const Elf_Internal_Rela *relocs;
{
bfd *dynobj;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
bfd_signed_vma *local_got_refcounts;
const Elf_Internal_Rela *rel;
const Elf_Internal_Rela *rel_end;
asection *sgot;
asection *srelgot;
asection *sreloc;
if (info->relocateable)
return true;
dynobj = elf_hash_table (info)->dynobj;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (abfd);
local_got_refcounts = elf_local_got_refcounts (abfd);
sgot = NULL;
srelgot = NULL;
sreloc = NULL;
rel_end = relocs + sec->reloc_count;
for (rel = relocs; rel < rel_end; rel++)
{
unsigned long r_symndx;
struct elf_link_hash_entry *h;
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))
{
case R_68K_GOT8:
case R_68K_GOT16:
case R_68K_GOT32:
if (h != NULL
&& strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
break;
/* Fall through. */
case R_68K_GOT8O:
case R_68K_GOT16O:
case R_68K_GOT32O:
/* This symbol requires a global offset table entry. */
if (dynobj == NULL)
{
/* Create the .got section. */
elf_hash_table (info)->dynobj = dynobj = abfd;
if (!_bfd_elf_create_got_section (dynobj, info))
return false;
}
if (sgot == NULL)
{
sgot = bfd_get_section_by_name (dynobj, ".got");
BFD_ASSERT (sgot != NULL);
}
if (srelgot == NULL
&& (h != NULL || info->shared))
{
srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
if (srelgot == NULL)
{
srelgot = bfd_make_section (dynobj, ".rela.got");
if (srelgot == NULL
|| !bfd_set_section_flags (dynobj, srelgot,
(SEC_ALLOC
| SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_IN_MEMORY
| SEC_LINKER_CREATED
| SEC_READONLY))
|| !bfd_set_section_alignment (dynobj, srelgot, 2))
return false;
}
}
if (h != NULL)
{
if (h->got.refcount == -1)
{
h->got.refcount = 1;
/* Make sure this symbol is output as a dynamic symbol. */
if (h->dynindx == -1)
{
if (!bfd_elf32_link_record_dynamic_symbol (info, h))
return false;
}
/* Allocate space in the .got section. */
sgot->_raw_size += 4;
/* Allocate relocation space. */
srelgot->_raw_size += sizeof (Elf32_External_Rela);
}
else
h->got.refcount++;
}
else
{
/* This is a global offset table entry for a local symbol. */
if (local_got_refcounts == NULL)
{
size_t size;
size = symtab_hdr->sh_info * sizeof (bfd_signed_vma);
local_got_refcounts = ((bfd_signed_vma *)
bfd_alloc (abfd, size));
if (local_got_refcounts == NULL)
return false;
elf_local_got_refcounts (abfd) = local_got_refcounts;
memset (local_got_refcounts, -1, size);
}
if (local_got_refcounts[r_symndx] == -1)
{
local_got_refcounts[r_symndx] = 1;
sgot->_raw_size += 4;
if (info->shared)
{
/* If we are generating a shared object, we need to
output a R_68K_RELATIVE reloc so that the dynamic
linker can adjust this GOT entry. */
srelgot->_raw_size += sizeof (Elf32_External_Rela);
}
}
else
local_got_refcounts[r_symndx]++;
}
break;
case R_68K_PLT8:
case R_68K_PLT16:
case R_68K_PLT32:
/* This symbol requires a procedure linkage table entry. We
actually build the entry in adjust_dynamic_symbol,
because this might be a case of linking PIC code which is
never referenced by a dynamic object, in which case we
don't need to generate a procedure linkage table entry
after all. */
/* If this is a local symbol, we resolve it directly without
creating a procedure linkage table entry. */
if (h == NULL)
continue;
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
if (h->plt.refcount == -1)
h->plt.refcount = 1;
else
h->plt.refcount++;
break;
case R_68K_PLT8O:
case R_68K_PLT16O:
case R_68K_PLT32O:
/* This symbol requires a procedure linkage table entry. */
if (h == NULL)
{
/* It does not make sense to have this relocation for a
local symbol. FIXME: does it? How to handle it if
it does make sense? */
bfd_set_error (bfd_error_bad_value);
return false;
}
/* Make sure this symbol is output as a dynamic symbol. */
if (h->dynindx == -1)
{
if (!bfd_elf32_link_record_dynamic_symbol (info, h))
return false;
}
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
if (h->plt.refcount == -1)
h->plt.refcount = 1;
else
h->plt.refcount++;
break;
case R_68K_PC8:
case R_68K_PC16:
case R_68K_PC32:
/* If we are creating a shared library and this is not a local
symbol, we need to copy the reloc into the shared library.
However when linking with -Bsymbolic and this is a global
symbol which is defined in an object we are including in the
link (i.e., DEF_REGULAR is set), then we can resolve the
reloc directly. At this point we have not seen all the input
files, so it is possible that DEF_REGULAR is not set now but
will be set later (it is never cleared). We account for that
possibility below by storing information in the
pcrel_relocs_copied field of the hash table entry. */
if (!(info->shared
&& (sec->flags & SEC_ALLOC) != 0
&& h != NULL
&& (!info->symbolic
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0)))
{
if (h != NULL)
{
/* Make sure a plt entry is created for this symbol if
it turns out to be a function defined by a dynamic
object. */
if (h->plt.refcount == -1)
h->plt.refcount = 1;
else
h->plt.refcount++;
}
break;
}
/* Fall through. */
case R_68K_8:
case R_68K_16:
case R_68K_32:
if (h != NULL)
{
/* Make sure a plt entry is created for this symbol if it
turns out to be a function defined by a dynamic object. */
if (h->plt.refcount == -1)
h->plt.refcount = 1;
else
h->plt.refcount++;
}
/* If we are creating a shared library, we need to copy the
reloc into the shared library. */
if (info->shared
&& (sec->flags & SEC_ALLOC) != 0)
{
/* When creating a shared object, we must copy these
reloc types into the output file. We create a reloc
section in dynobj and make room for this reloc. */
if (sreloc == NULL)
{
const char *name;
name = (bfd_elf_string_from_elf_section
(abfd,
elf_elfheader (abfd)->e_shstrndx,
elf_section_data (sec)->rel_hdr.sh_name));
if (name == NULL)
return false;
BFD_ASSERT (strncmp (name, ".rela", 5) == 0
&& strcmp (bfd_get_section_name (abfd, sec),
name + 5) == 0);
sreloc = bfd_get_section_by_name (dynobj, name);
if (sreloc == NULL)
{
sreloc = bfd_make_section (dynobj, name);
if (sreloc == NULL
|| !bfd_set_section_flags (dynobj, sreloc,
(SEC_ALLOC
| SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_IN_MEMORY
| SEC_LINKER_CREATED
| SEC_READONLY))
|| !bfd_set_section_alignment (dynobj, sreloc, 2))
return false;
}
}
sreloc->_raw_size += sizeof (Elf32_External_Rela);
/* If we are linking with -Bsymbolic, we count the number of
PC relative relocations we have entered for this symbol,
so that we can discard them again if the symbol is later
defined by a regular object. Note that this function is
only called if we are using an m68kelf linker hash table,
which means that h is really a pointer to an
elf_m68k_link_hash_entry. */
if ((ELF32_R_TYPE (rel->r_info) == R_68K_PC8
|| ELF32_R_TYPE (rel->r_info) == R_68K_PC16
|| ELF32_R_TYPE (rel->r_info) == R_68K_PC32)
&& info->symbolic)
{
struct elf_m68k_link_hash_entry *eh;
struct elf_m68k_pcrel_relocs_copied *p;
eh = (struct elf_m68k_link_hash_entry *) h;
for (p = eh->pcrel_relocs_copied; p != NULL; p = p->next)
if (p->section == sreloc)
break;
if (p == NULL)
{
p = ((struct elf_m68k_pcrel_relocs_copied *)
bfd_alloc (dynobj, sizeof *p));
if (p == NULL)
return false;
p->next = eh->pcrel_relocs_copied;
eh->pcrel_relocs_copied = p;
p->section = sreloc;
p->count = 0;
}
++p->count;
}
}
break;
/* This relocation describes the C++ object vtable hierarchy.
Reconstruct it for later use during GC. */
case R_68K_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_68K_GNU_VTENTRY:
if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
return false;
break;
default:
break;
}
}
return true;
}
/* Return the section that should be marked against GC for a given
relocation. */
static asection *
elf_m68k_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_68K_GNU_VTINHERIT:
case R_68K_GNU_VTENTRY:
break;
default:
switch (h->root.type)
{
default:
break;
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;
}
}
}
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
elf_m68k_gc_sweep_hook (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;
bfd_signed_vma *local_got_refcounts;
const Elf_Internal_Rela *rel, *relend;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
bfd *dynobj;
asection *sgot;
asection *srelgot;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (abfd);
local_got_refcounts = elf_local_got_refcounts (abfd);
dynobj = elf_hash_table (info)->dynobj;
if (dynobj == NULL)
return true;
sgot = bfd_get_section_by_name (dynobj, ".got");
srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
relend = relocs + sec->reloc_count;
for (rel = relocs; rel < relend; rel++)
{
switch (ELF32_R_TYPE (rel->r_info))
{
case R_68K_GOT8:
case R_68K_GOT16:
case R_68K_GOT32:
case R_68K_GOT8O:
case R_68K_GOT16O:
case R_68K_GOT32O:
r_symndx = ELF32_R_SYM (rel->r_info);
if (r_symndx >= symtab_hdr->sh_info)
{
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
if (h->got.refcount > 0)
{
--h->got.refcount;
if (h->got.refcount == 0)
{
/* We don't need the .got entry any more. */
sgot->_raw_size -= 4;
srelgot->_raw_size -= sizeof (Elf32_External_Rela);
}
}
}
else if (local_got_refcounts != NULL)
{
if (local_got_refcounts[r_symndx] > 0)
{
--local_got_refcounts[r_symndx];
if (local_got_refcounts[r_symndx] == 0)
{
/* We don't need the .got entry any more. */
sgot->_raw_size -= 4;
if (info->shared)
srelgot->_raw_size -= sizeof (Elf32_External_Rela);
}
}
}
break;
case R_68K_PLT8:
case R_68K_PLT16:
case R_68K_PLT32:
case R_68K_PLT8O:
case R_68K_PLT16O:
case R_68K_PLT32O:
case R_68K_PC8:
case R_68K_PC16:
case R_68K_PC32:
case R_68K_8:
case R_68K_16:
case R_68K_32:
r_symndx = ELF32_R_SYM (rel->r_info);
if (r_symndx >= symtab_hdr->sh_info)
{
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
if (h->plt.refcount > 0)
--h->plt.refcount;
}
break;
default:
break;
}
}
return true;
}
/* Adjust a symbol defined by a dynamic object and referenced by a
regular object. The current definition is in some section of the
dynamic object, but we're not including those sections. We have to
change the definition to something the rest of the link can
understand. */
static boolean
elf_m68k_adjust_dynamic_symbol (info, h)
struct bfd_link_info *info;
struct elf_link_hash_entry *h;
{
bfd *dynobj;
asection *s;
unsigned int power_of_two;
dynobj = elf_hash_table (info)->dynobj;
/* Make sure we know what is going on here. */
BFD_ASSERT (dynobj != NULL
&& ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
|| h->weakdef != NULL
|| ((h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_DYNAMIC) != 0
&& (h->elf_link_hash_flags
& ELF_LINK_HASH_REF_REGULAR) != 0
&& (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0)));
/* If this is a function, put it in the procedure linkage table. We
will fill in the contents of the procedure linkage table later,
when we know the address of the .got section. */
if (h->type == STT_FUNC
|| (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
{
if (! info->shared
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
&& (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0
/* We must always create the plt entry if it was referenced
by a PLTxxO relocation. In this case we already recorded
it as a dynamic symbol. */
&& h->dynindx == -1)
{
/* This case can occur if we saw a PLTxx reloc in an input
file, but the symbol was never referred to by a dynamic
object. In such a case, we don't actually need to build
a procedure linkage table, and we can just do a PCxx
reloc instead. */
BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
h->plt.offset = (bfd_vma) -1;
return true;
}
/* GC may have rendered this entry unused. */
if (h->plt.refcount <= 0)
{
h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
h->plt.offset = (bfd_vma) -1;
return true;
}
/* Make sure this symbol is output as a dynamic symbol. */
if (h->dynindx == -1)
{
if (! bfd_elf32_link_record_dynamic_symbol (info, h))
return false;
}
s = bfd_get_section_by_name (dynobj, ".plt");
BFD_ASSERT (s != NULL);
/* If this is the first .plt entry, make room for the special
first entry. */
if (s->_raw_size == 0)
{
if (CPU32_FLAG (dynobj))
s->_raw_size += PLT_CPU32_ENTRY_SIZE;
else
s->_raw_size += PLT_ENTRY_SIZE;
}
/* If this symbol is not defined in a regular file, and we are
not generating a shared library, then set the symbol to this
location in the .plt. This is required to make function
pointers compare as equal between the normal executable and
the shared library. */
if (!info->shared
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
{
h->root.u.def.section = s;
h->root.u.def.value = s->_raw_size;
}
h->plt.offset = s->_raw_size;
/* Make room for this entry. */
if (CPU32_FLAG (dynobj))
s->_raw_size += PLT_CPU32_ENTRY_SIZE;
else
s->_raw_size += PLT_ENTRY_SIZE;
/* We also need to make an entry in the .got.plt section, which
will be placed in the .got section by the linker script. */
s = bfd_get_section_by_name (dynobj, ".got.plt");
BFD_ASSERT (s != NULL);
s->_raw_size += 4;
/* We also need to make an entry in the .rela.plt section. */
s = bfd_get_section_by_name (dynobj, ".rela.plt");
BFD_ASSERT (s != NULL);
s->_raw_size += sizeof (Elf32_External_Rela);
return true;
}
/* Reinitialize the plt offset now that it is not used as a reference
count any more. */
h->plt.offset = (bfd_vma) -1;
/* If this is a weak symbol, and there is a real definition, the
processor independent code will have arranged for us to see the
real definition first, and we can just use the same value. */
if (h->weakdef != NULL)
{
BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
|| h->weakdef->root.type == bfd_link_hash_defweak);
h->root.u.def.section = h->weakdef->root.u.def.section;
h->root.u.def.value = h->weakdef->root.u.def.value;
return true;
}
/* This is a reference to a symbol defined by a dynamic object which
is not a function. */
/* If we are creating a shared library, we must presume that the
only references to the symbol are via the global offset table.
For such cases we need not do anything here; the relocations will
be handled correctly by relocate_section. */
if (info->shared)
return true;
/* We must allocate the symbol in our .dynbss section, which will
become part of the .bss section of the executable. There will be
an entry for this symbol in the .dynsym section. The dynamic
object will contain position independent code, so all references
from the dynamic object to this symbol will go through the global
offset table. The dynamic linker will use the .dynsym entry to
determine the address it must put in the global offset table, so
both the dynamic object and the regular object will refer to the
same memory location for the variable. */
s = bfd_get_section_by_name (dynobj, ".dynbss");
BFD_ASSERT (s != NULL);
/* We must generate a R_68K_COPY reloc to tell the dynamic linker to
copy the initial value out of the dynamic object and into the
runtime process image. We need to remember the offset into the
.rela.bss section we are going to use. */
if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
{
asection *srel;
srel = bfd_get_section_by_name (dynobj, ".rela.bss");
BFD_ASSERT (srel != NULL);
srel->_raw_size += sizeof (Elf32_External_Rela);
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
}
/* We need to figure out the alignment required for this symbol. I
have no idea how ELF linkers handle this. */
power_of_two = bfd_log2 (h->size);
if (power_of_two > 3)
power_of_two = 3;
/* Apply the required alignment. */
s->_raw_size = BFD_ALIGN (s->_raw_size,
(bfd_size_type) (1 << power_of_two));
if (power_of_two > bfd_get_section_alignment (dynobj, s))
{
if (!bfd_set_section_alignment (dynobj, s, power_of_two))
return false;
}
/* Define the symbol as being at this point in the section. */
h->root.u.def.section = s;
h->root.u.def.value = s->_raw_size;
/* Increment the section size to make room for the symbol. */
s->_raw_size += h->size;
return true;
}
/* Set the sizes of the dynamic sections. */
static boolean
elf_m68k_size_dynamic_sections (output_bfd, info)
bfd *output_bfd;
struct bfd_link_info *info;
{
bfd *dynobj;
asection *s;
boolean plt;
boolean relocs;
boolean reltext;
dynobj = elf_hash_table (info)->dynobj;
BFD_ASSERT (dynobj != NULL);
if (elf_hash_table (info)->dynamic_sections_created)
{
/* Set the contents of the .interp section to the interpreter. */
if (!info->shared)
{
s = bfd_get_section_by_name (dynobj, ".interp");
BFD_ASSERT (s != NULL);
s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
}
}
else
{
/* We may have created entries in the .rela.got section.
However, if we are not creating the dynamic sections, we will
not actually use these entries. Reset the size of .rela.got,
which will cause it to get stripped from the output file
below. */
s = bfd_get_section_by_name (dynobj, ".rela.got");
if (s != NULL)
s->_raw_size = 0;
}
/* If this is a -Bsymbolic shared link, then we need to discard all PC
relative relocs against symbols defined in a regular object. We
allocated space for them in the check_relocs routine, but we will not
fill them in in the relocate_section routine. */
if (info->shared && info->symbolic)
elf_m68k_link_hash_traverse (elf_m68k_hash_table (info),
elf_m68k_discard_copies,
(PTR) NULL);
/* The check_relocs and adjust_dynamic_symbol entry points have
determined the sizes of the various dynamic sections. Allocate
memory for them. */
plt = false;
relocs = false;
reltext = false;
for (s = dynobj->sections; s != NULL; s = s->next)
{
const char *name;
boolean strip;
if ((s->flags & SEC_LINKER_CREATED) == 0)
continue;
/* It's OK to base decisions on the section name, because none
of the dynobj section names depend upon the input files. */
name = bfd_get_section_name (dynobj, s);
strip = false;
if (strcmp (name, ".plt") == 0)
{
if (s->_raw_size == 0)
{
/* Strip this section if we don't need it; see the
comment below. */
strip = true;
}
else
{
/* Remember whether there is a PLT. */
plt = true;
}
}
else if (strncmp (name, ".rela", 5) == 0)
{
if (s->_raw_size == 0)
{
/* If we don't need this section, strip it from the
output file. This is mostly to handle .rela.bss and
.rela.plt. We must create both sections in
create_dynamic_sections, because they must be created
before the linker maps input sections to output
sections. The linker does that before
adjust_dynamic_symbol is called, and it is that
function which decides whether anything needs to go
into these sections. */
strip = true;
}
else
{
asection *target;
/* Remember whether there are any reloc sections other
than .rela.plt. */
if (strcmp (name, ".rela.plt") != 0)
{
const char *outname;
relocs = true;
/* If this relocation section applies to a read only
section, then we probably need a DT_TEXTREL
entry. .rela.plt is actually associated with
.got.plt, which is never readonly. */
outname = bfd_get_section_name (output_bfd,
s->output_section);
target = bfd_get_section_by_name (output_bfd, outname + 5);
if (target != NULL
&& (target->flags & SEC_READONLY) != 0
&& (target->flags & SEC_ALLOC) != 0)
reltext = true;
}
/* We use the reloc_count field as a counter if we need
to copy relocs into the output file. */
s->reloc_count = 0;
}
}
else if (strncmp (name, ".got", 4) != 0)
{
/* It's not one of our sections, so don't allocate space. */
continue;
}
if (strip)
{
_bfd_strip_section_from_output (info, s);
continue;
}
/* Allocate memory for the section contents. */
s->contents = (bfd_byte *) bfd_alloc (dynobj, s->_raw_size);
if (s->contents == NULL && s->_raw_size != 0)
return false;
}
if (elf_hash_table (info)->dynamic_sections_created)
{
/* Add some entries to the .dynamic section. We fill in the
values later, in elf_m68k_finish_dynamic_sections, but we
must add the entries now so that we get the correct size for
the .dynamic section. The DT_DEBUG entry is filled in by the
dynamic linker and used by the debugger. */
if (!info->shared)
{
if (!bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
return false;
}
if (plt)
{
if (!bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
|| !bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
|| !bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_RELA)
|| !bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
return false;
}
if (relocs)
{
if (!bfd_elf32_add_dynamic_entry (info, DT_RELA, 0)
|| !bfd_elf32_add_dynamic_entry (info, DT_RELASZ, 0)
|| !bfd_elf32_add_dynamic_entry (info, DT_RELAENT,
sizeof (Elf32_External_Rela)))
return false;
}
if (reltext)
{
if (!bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
return false;
}
}
return true;
}
/* This function is called via elf_m68k_link_hash_traverse if we are
creating a shared object with -Bsymbolic. It discards the space
allocated to copy PC relative relocs against symbols which are defined
in regular objects. We allocated space for them in the check_relocs
routine, but we won't fill them in in the relocate_section routine. */
/*ARGSUSED*/
static boolean
elf_m68k_discard_copies (h, ignore)
struct elf_m68k_link_hash_entry *h;
PTR ignore ATTRIBUTE_UNUSED;
{
struct elf_m68k_pcrel_relocs_copied *s;
/* We only discard relocs for symbols defined in a regular object. */
if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
return true;
for (s = h->pcrel_relocs_copied; s != NULL; s = s->next)
s->section->_raw_size -= s->count * sizeof (Elf32_External_Rela);
return true;
}
/* Relocate an M68K ELF section. */
static boolean
elf_m68k_relocate_section (output_bfd, info, input_bfd, input_section,
contents, relocs, local_syms, local_sections)
bfd *output_bfd;
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;
{
bfd *dynobj;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
bfd_vma *local_got_offsets;
asection *sgot;
asection *splt;
asection *sreloc;
Elf_Internal_Rela *rel;
Elf_Internal_Rela *relend;
dynobj = elf_hash_table (info)->dynobj;
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (input_bfd);
local_got_offsets = elf_local_got_offsets (input_bfd);
sgot = NULL;
splt = NULL;
sreloc = NULL;
rel = relocs;
relend = relocs + input_section->reloc_count;
for (; rel < relend; rel++)
{
int r_type;
reloc_howto_type *howto;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
Elf_Internal_Sym *sym;
asection *sec;
bfd_vma relocation;
bfd_reloc_status_type r;
r_type = ELF32_R_TYPE (rel->r_info);
if (r_type < 0 || r_type >= (int) R_68K_max)
{
bfd_set_error (bfd_error_bad_value);
return false;
}
howto = howto_table + r_type;
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. */
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);
}
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;
if (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak)
{
sec = h->root.u.def.section;
if (((r_type == R_68K_PLT8
|| r_type == R_68K_PLT16
|| r_type == R_68K_PLT32
|| r_type == R_68K_PLT8O
|| r_type == R_68K_PLT16O
|| r_type == R_68K_PLT32O)
&& h->plt.offset != (bfd_vma) -1
&& elf_hash_table (info)->dynamic_sections_created)
|| ((r_type == R_68K_GOT8O
|| r_type == R_68K_GOT16O
|| r_type == R_68K_GOT32O
|| ((r_type == R_68K_GOT8
|| r_type == R_68K_GOT16
|| r_type == R_68K_GOT32)
&& strcmp (h->root.root.string,
"_GLOBAL_OFFSET_TABLE_") != 0))
&& elf_hash_table (info)->dynamic_sections_created
&& (! info->shared
|| (! info->symbolic && h->dynindx != -1)
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0))
|| (info->shared
&& ((! info->symbolic && h->dynindx != -1)
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0)
&& (input_section->flags & SEC_ALLOC) != 0
&& (r_type == R_68K_8
|| r_type == R_68K_16
|| r_type == R_68K_32
|| r_type == R_68K_PC8
|| r_type == R_68K_PC16
|| r_type == R_68K_PC32)))
{
/* In these cases, we don't need the relocation
value. We check specially because in some
obscure cases sec->output_section will be NULL. */
relocation = 0;
}
else
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->shared && !info->symbolic && !info->no_undefined)
relocation = 0;
else
{
if (!(info->callbacks->undefined_symbol
(info, h->root.root.string, input_bfd,
input_section, rel->r_offset,
(!info->shared || info->no_undefined))))
return false;
relocation = 0;
}
}
switch (r_type)
{
case R_68K_GOT8:
case R_68K_GOT16:
case R_68K_GOT32:
/* Relocation is to the address of the entry for this symbol
in the global offset table. */
if (h != NULL
&& strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
break;
/* Fall through. */
case R_68K_GOT8O:
case R_68K_GOT16O:
case R_68K_GOT32O:
/* Relocation is the offset of the entry for this symbol in
the global offset table. */
{
bfd_vma off;
if (sgot == NULL)
{
sgot = bfd_get_section_by_name (dynobj, ".got");
BFD_ASSERT (sgot != NULL);
}
if (h != NULL)
{
off = h->got.offset;
BFD_ASSERT (off != (bfd_vma) -1);
if (!elf_hash_table (info)->dynamic_sections_created
|| (info->shared
&& (info->symbolic || h->dynindx == -1)
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
{
/* This is actually a static link, or it is a
-Bsymbolic link and the symbol is defined
locally, or the symbol was forced to be local
because of a version file.. We must initialize
this entry in the global offset table. Since
the offset must always be a multiple of 4, we
use the least significant bit to record whether
we have initialized it already.
When doing a dynamic link, we create a .rela.got
relocation entry to initialize the value. This
is done in the finish_dynamic_symbol routine. */
if ((off & 1) != 0)
off &= ~1;
else
{
bfd_put_32 (output_bfd, relocation,
sgot->contents + off);
h->got.offset |= 1;
}
}
}
else
{
BFD_ASSERT (local_got_offsets != NULL
&& local_got_offsets[r_symndx] != (bfd_vma) -1);
off = local_got_offsets[r_symndx];
/* The offset must always be a multiple of 4. We use
the least significant bit to record whether we have
already generated the necessary reloc. */
if ((off & 1) != 0)
off &= ~1;
else
{
bfd_put_32 (output_bfd, relocation, sgot->contents + off);
if (info->shared)
{
asection *srelgot;
Elf_Internal_Rela outrel;
srelgot = bfd_get_section_by_name (dynobj, ".rela.got");
BFD_ASSERT (srelgot != NULL);
outrel.r_offset = (sgot->output_section->vma
+ sgot->output_offset
+ off);
outrel.r_info = ELF32_R_INFO (0, R_68K_RELATIVE);
outrel.r_addend = relocation;
bfd_elf32_swap_reloca_out (output_bfd, &outrel,
(((Elf32_External_Rela *)
srelgot->contents)
+ srelgot->reloc_count));
++srelgot->reloc_count;
}
local_got_offsets[r_symndx] |= 1;
}
}
relocation = sgot->output_offset + off;
if (r_type == R_68K_GOT8O
|| r_type == R_68K_GOT16O
|| r_type == R_68K_GOT32O)
{
/* This relocation does not use the addend. */
rel->r_addend = 0;
}
else
relocation += sgot->output_section->vma;
}
break;
case R_68K_PLT8:
case R_68K_PLT16:
case R_68K_PLT32:
/* Relocation is to the entry for this symbol in the
procedure linkage table. */
/* Resolve a PLTxx reloc against a local symbol directly,
without using the procedure linkage table. */
if (h == NULL)
break;
if (h->plt.offset == (bfd_vma) -1
|| !elf_hash_table (info)->dynamic_sections_created)
{
/* We didn't make a PLT entry for this symbol. This
happens when statically linking PIC code, or when
using -Bsymbolic. */
break;
}
if (splt == NULL)
{
splt = bfd_get_section_by_name (dynobj, ".plt");
BFD_ASSERT (splt != NULL);
}
relocation = (splt->output_section->vma
+ splt->output_offset
+ h->plt.offset);
break;
case R_68K_PLT8O:
case R_68K_PLT16O:
case R_68K_PLT32O:
/* Relocation is the offset of the entry for this symbol in
the procedure linkage table. */
BFD_ASSERT (h != NULL && h->plt.offset != (bfd_vma) -1);
if (splt == NULL)
{
splt = bfd_get_section_by_name (dynobj, ".plt");
BFD_ASSERT (splt != NULL);
}
relocation = h->plt.offset;
/* This relocation does not use the addend. */
rel->r_addend = 0;
break;
case R_68K_PC8:
case R_68K_PC16:
case R_68K_PC32:
if (h == NULL)
break;
/* Fall through. */
case R_68K_8:
case R_68K_16:
case R_68K_32:
if (info->shared
&& (input_section->flags & SEC_ALLOC) != 0
&& ((r_type != R_68K_PC8
&& r_type != R_68K_PC16
&& r_type != R_68K_PC32)
|| (!info->symbolic
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0)))
{
Elf_Internal_Rela outrel;
boolean skip, relocate;
/* When generating a shared object, these relocations
are copied into the output file to be resolved at run
time. */
if (sreloc == NULL)
{
const char *name;
name = (bfd_elf_string_from_elf_section
(input_bfd,
elf_elfheader (input_bfd)->e_shstrndx,
elf_section_data (input_section)->rel_hdr.sh_name));
if (name == NULL)
return false;
BFD_ASSERT (strncmp (name, ".rela", 5) == 0
&& strcmp (bfd_get_section_name (input_bfd,
input_section),
name + 5) == 0);
sreloc = bfd_get_section_by_name (dynobj, name);
BFD_ASSERT (sreloc != NULL);
}
skip = false;
if (elf_section_data (input_section)->stab_info == NULL)
outrel.r_offset = rel->r_offset;
else
{
bfd_vma off;
off = (_bfd_stab_section_offset
(output_bfd, &elf_hash_table (info)->stab_info,
input_section,
&elf_section_data (input_section)->stab_info,
rel->r_offset));
if (off == (bfd_vma) -1)
skip = true;
outrel.r_offset = off;
}
outrel.r_offset += (input_section->output_section->vma
+ input_section->output_offset);
if (skip)
{
memset (&outrel, 0, sizeof outrel);
relocate = false;
}
/* h->dynindx may be -1 if the symbol was marked to
become local. */
else if (h != NULL
&& ((! info->symbolic && h->dynindx != -1)
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0))
{
BFD_ASSERT (h->dynindx != -1);
relocate = false;
outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
outrel.r_addend = relocation + rel->r_addend;
}
else
{
if (r_type == R_68K_32)
{
relocate = true;
outrel.r_info = ELF32_R_INFO (0, R_68K_RELATIVE);
outrel.r_addend = relocation + rel->r_addend;
}
else
{
long indx;
if (h == NULL)
sec = local_sections[r_symndx];
else
{
BFD_ASSERT (h->root.type == bfd_link_hash_defined
|| (h->root.type
== bfd_link_hash_defweak));
sec = h->root.u.def.section;
}
if (sec != NULL && bfd_is_abs_section (sec))
indx = 0;
else if (sec == NULL || sec->owner == NULL)
{
bfd_set_error (bfd_error_bad_value);
return false;
}
else
{
asection *osec;
osec = sec->output_section;
indx = elf_section_data (osec)->dynindx;
BFD_ASSERT (indx > 0);
}
relocate = false;
outrel.r_info = ELF32_R_INFO (indx, r_type);
outrel.r_addend = relocation + rel->r_addend;
}
}
bfd_elf32_swap_reloca_out (output_bfd, &outrel,
(((Elf32_External_Rela *)
sreloc->contents)
+ sreloc->reloc_count));
++sreloc->reloc_count;
/* This reloc will be computed at runtime, so there's no
need to do anything now, except for R_68K_32
relocations that have been turned into
R_68K_RELATIVE. */
if (!relocate)
continue;
}
break;
case R_68K_GNU_VTINHERIT:
case R_68K_GNU_VTENTRY:
/* These are no-ops in the end. */
continue;
default:
break;
}
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
relocation, rel->r_addend);
if (r != bfd_reloc_ok)
{
switch (r)
{
default:
case bfd_reloc_outofrange:
abort ();
case bfd_reloc_overflow:
{
const char *name;
if (h != NULL)
name = h->root.root.string;
else
{
name = bfd_elf_string_from_elf_section (input_bfd,
symtab_hdr->sh_link,
sym->st_name);
if (name == NULL)
return false;
if (*name == '\0')
name = bfd_section_name (input_bfd, sec);
}
if (!(info->callbacks->reloc_overflow
(info, name, howto->name, (bfd_vma) 0,
input_bfd, input_section, rel->r_offset)))
return false;
}
break;
}
}
}
return true;
}
/* Finish up dynamic symbol handling. We set the contents of various
dynamic sections here. */
static boolean
elf_m68k_finish_dynamic_symbol (output_bfd, info, h, sym)
bfd *output_bfd;
struct bfd_link_info *info;
struct elf_link_hash_entry *h;
Elf_Internal_Sym *sym;
{
bfd *dynobj;
int plt_off1, plt_off2, plt_off3;
dynobj = elf_hash_table (info)->dynobj;
if (h->plt.offset != (bfd_vma) -1)
{
asection *splt;
asection *sgot;
asection *srela;
bfd_vma plt_index;
bfd_vma got_offset;
Elf_Internal_Rela rela;
/* This symbol has an entry in the procedure linkage table. Set
it up. */
BFD_ASSERT (h->dynindx != -1);
splt = bfd_get_section_by_name (dynobj, ".plt");
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
srela = bfd_get_section_by_name (dynobj, ".rela.plt");
BFD_ASSERT (splt != NULL && sgot != NULL && srela != NULL);
/* Get the index in the procedure linkage table which
corresponds to this symbol. This is the index of this symbol
in all the symbols for which we are making plt entries. The
first entry in the procedure linkage table is reserved. */
if ( CPU32_FLAG (output_bfd))
plt_index = h->plt.offset / PLT_CPU32_ENTRY_SIZE - 1;
else
plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
/* Get the offset into the .got table of the entry that
corresponds to this function. Each .got entry is 4 bytes.
The first three are reserved. */
got_offset = (plt_index + 3) * 4;
if ( CPU32_FLAG (output_bfd))
{
/* Fill in the entry in the procedure linkage table. */
memcpy (splt->contents + h->plt.offset, elf_cpu32_plt_entry,
PLT_CPU32_ENTRY_SIZE);
plt_off1 = 4;
plt_off2 = 12;
plt_off3 = 18;
}
else
{
/* Fill in the entry in the procedure linkage table. */
memcpy (splt->contents + h->plt.offset, elf_m68k_plt_entry,
PLT_ENTRY_SIZE);
plt_off1 = 4;
plt_off2 = 10;
plt_off3 = 16;
}
/* The offset is relative to the first extension word. */
bfd_put_32 (output_bfd,
(sgot->output_section->vma
+ sgot->output_offset
+ got_offset
- (splt->output_section->vma
+ h->plt.offset + 2)),
splt->contents + h->plt.offset + plt_off1);
bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rela),
splt->contents + h->plt.offset + plt_off2);
bfd_put_32 (output_bfd, - (h->plt.offset + plt_off3),
splt->contents + h->plt.offset + plt_off3);
/* Fill in the entry in the global offset table. */
bfd_put_32 (output_bfd,
(splt->output_section->vma
+ splt->output_offset
+ h->plt.offset
+ 8),
sgot->contents + got_offset);
/* Fill in the entry in the .rela.plt section. */
rela.r_offset = (sgot->output_section->vma
+ sgot->output_offset
+ got_offset);
rela.r_info = ELF32_R_INFO (h->dynindx, R_68K_JMP_SLOT);
rela.r_addend = 0;
bfd_elf32_swap_reloca_out (output_bfd, &rela,
((Elf32_External_Rela *) srela->contents
+ plt_index));
if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
{
/* Mark the symbol as undefined, rather than as defined in
the .plt section. Leave the value alone. */
sym->st_shndx = SHN_UNDEF;
}
}
if (h->got.offset != (bfd_vma) -1)
{
asection *sgot;
asection *srela;
Elf_Internal_Rela rela;
/* This symbol has an entry in the global offset table. Set it
up. */
sgot = bfd_get_section_by_name (dynobj, ".got");
srela = bfd_get_section_by_name (dynobj, ".rela.got");
BFD_ASSERT (sgot != NULL && srela != NULL);
rela.r_offset = (sgot->output_section->vma
+ sgot->output_offset
+ (h->got.offset &~ 1));
/* If this is a -Bsymbolic link, and the symbol is defined
locally, we just want to emit a RELATIVE reloc. Likewise if
the symbol was forced to be local because of a version file.
The entry in the global offset table will already have been
initialized in the relocate_section function. */
if (info->shared
&& (info->symbolic || h->dynindx == -1)
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
{
rela.r_info = ELF32_R_INFO (0, R_68K_RELATIVE);
rela.r_addend = bfd_get_signed_32 (output_bfd,
(sgot->contents
+ (h->got.offset & ~1)));
}
else
{
bfd_put_32 (output_bfd, (bfd_vma) 0,
sgot->contents + (h->got.offset & ~1));
rela.r_info = ELF32_R_INFO (h->dynindx, R_68K_GLOB_DAT);
rela.r_addend = 0;
}
bfd_elf32_swap_reloca_out (output_bfd, &rela,
((Elf32_External_Rela *) srela->contents
+ srela->reloc_count));
++srela->reloc_count;
}
if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
{
asection *s;
Elf_Internal_Rela rela;
/* This symbol needs a copy reloc. Set it up. */
BFD_ASSERT (h->dynindx != -1
&& (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak));
s = bfd_get_section_by_name (h->root.u.def.section->owner,
".rela.bss");
BFD_ASSERT (s != NULL);
rela.r_offset = (h->root.u.def.value
+ h->root.u.def.section->output_section->vma
+ h->root.u.def.section->output_offset);
rela.r_info = ELF32_R_INFO (h->dynindx, R_68K_COPY);
rela.r_addend = 0;
bfd_elf32_swap_reloca_out (output_bfd, &rela,
((Elf32_External_Rela *) s->contents
+ s->reloc_count));
++s->reloc_count;
}
/* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
if (strcmp (h->root.root.string, "_DYNAMIC") == 0
|| strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
sym->st_shndx = SHN_ABS;
return true;
}
/* Finish up the dynamic sections. */
static boolean
elf_m68k_finish_dynamic_sections (output_bfd, info)
bfd *output_bfd;
struct bfd_link_info *info;
{
bfd *dynobj;
asection *sgot;
asection *sdyn;
dynobj = elf_hash_table (info)->dynobj;
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
BFD_ASSERT (sgot != NULL);
sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
if (elf_hash_table (info)->dynamic_sections_created)
{
asection *splt;
Elf32_External_Dyn *dyncon, *dynconend;
splt = bfd_get_section_by_name (dynobj, ".plt");
BFD_ASSERT (splt != NULL && sdyn != NULL);
dyncon = (Elf32_External_Dyn *) sdyn->contents;
dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
for (; dyncon < dynconend; dyncon++)
{
Elf_Internal_Dyn dyn;
const char *name;
asection *s;
bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
switch (dyn.d_tag)
{
default:
break;
case DT_PLTGOT:
name = ".got";
goto get_vma;
case DT_JMPREL:
name = ".rela.plt";
get_vma:
s = bfd_get_section_by_name (output_bfd, name);
BFD_ASSERT (s != NULL);
dyn.d_un.d_ptr = s->vma;
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
break;
case DT_PLTRELSZ:
s = bfd_get_section_by_name (output_bfd, ".rela.plt");
BFD_ASSERT (s != NULL);
if (s->_cooked_size != 0)
dyn.d_un.d_val = s->_cooked_size;
else
dyn.d_un.d_val = s->_raw_size;
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
break;
case DT_RELASZ:
/* The procedure linkage table relocs (DT_JMPREL) should
not be included in the overall relocs (DT_RELA).
Therefore, we override the DT_RELASZ entry here to
make it not include the JMPREL relocs. Since the
linker script arranges for .rela.plt to follow all
other relocation sections, we don't have to worry
about changing the DT_RELA entry. */
s = bfd_get_section_by_name (output_bfd, ".rela.plt");
if (s != NULL)
{
if (s->_cooked_size != 0)
dyn.d_un.d_val -= s->_cooked_size;
else
dyn.d_un.d_val -= s->_raw_size;
}
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
break;
}
}
/* Fill in the first entry in the procedure linkage table. */
if (splt->_raw_size > 0)
{
if (!CPU32_FLAG (output_bfd))
{
memcpy (splt->contents, elf_m68k_plt0_entry, PLT_ENTRY_SIZE);
bfd_put_32 (output_bfd,
(sgot->output_section->vma
+ sgot->output_offset + 4
- (splt->output_section->vma + 2)),
splt->contents + 4);
bfd_put_32 (output_bfd,
(sgot->output_section->vma
+ sgot->output_offset + 8
- (splt->output_section->vma + 10)),
splt->contents + 12);
elf_section_data (splt->output_section)->this_hdr.sh_entsize
= PLT_ENTRY_SIZE;
}
else /* cpu32 */
{
memcpy (splt->contents, elf_cpu32_plt0_entry, PLT_CPU32_ENTRY_SIZE);
bfd_put_32 (output_bfd,
(sgot->output_section->vma
+ sgot->output_offset + 4
- (splt->output_section->vma + 2)),
splt->contents + 4);
bfd_put_32 (output_bfd,
(sgot->output_section->vma
+ sgot->output_offset + 8
- (splt->output_section->vma + 10)),
splt->contents + 10);
elf_section_data (splt->output_section)->this_hdr.sh_entsize
= PLT_CPU32_ENTRY_SIZE;
}
}
}
/* Fill in the first three entries in the global offset table. */
if (sgot->_raw_size > 0)
{
if (sdyn == NULL)
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
else
bfd_put_32 (output_bfd,
sdyn->output_section->vma + sdyn->output_offset,
sgot->contents);
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
}
elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
return true;
}
#define TARGET_BIG_SYM bfd_elf32_m68k_vec
#define TARGET_BIG_NAME "elf32-m68k"
#define ELF_MACHINE_CODE EM_68K
#define ELF_MAXPAGESIZE 0x2000
#define elf_backend_create_dynamic_sections \
_bfd_elf_create_dynamic_sections
#define bfd_elf32_bfd_link_hash_table_create \
elf_m68k_link_hash_table_create
#define bfd_elf32_bfd_final_link _bfd_elf32_gc_common_final_link
#define elf_backend_check_relocs elf_m68k_check_relocs
#define elf_backend_adjust_dynamic_symbol \
elf_m68k_adjust_dynamic_symbol
#define elf_backend_size_dynamic_sections \
elf_m68k_size_dynamic_sections
#define elf_backend_relocate_section elf_m68k_relocate_section
#define elf_backend_finish_dynamic_symbol \
elf_m68k_finish_dynamic_symbol
#define elf_backend_finish_dynamic_sections \
elf_m68k_finish_dynamic_sections
#define elf_backend_gc_mark_hook elf_m68k_gc_mark_hook
#define elf_backend_gc_sweep_hook elf_m68k_gc_sweep_hook
#define bfd_elf32_bfd_copy_private_bfd_data \
elf32_m68k_copy_private_bfd_data
#define bfd_elf32_bfd_merge_private_bfd_data \
elf32_m68k_merge_private_bfd_data
#define bfd_elf32_bfd_set_private_flags \
elf32_m68k_set_private_flags
#define bfd_elf32_bfd_print_private_bfd_data \
elf32_m68k_print_private_bfd_data
#define elf_backend_can_gc_sections 1
#define elf_backend_want_got_plt 1
#define elf_backend_plt_readonly 1
#define elf_backend_want_plt_sym 0
#define elf_backend_got_header_size 12
#include "elf32-target.h"
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