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544 lines
17 KiB
C
544 lines
17 KiB
C
/* BFD back-end for Motorola 68000 COFF binaries.
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Copyright (C) 1990-2014 Free Software Foundation, Inc.
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Written by Cygnus Support.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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#include "sysdep.h"
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#include "bfd.h"
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#include "libbfd.h"
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#include "coff/m68k.h"
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#include "coff/internal.h"
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#include "libcoff.h"
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/* This source file is compiled multiple times for various m68k COFF
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variants. The following macros control its behaviour:
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TARGET_SYM
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The C name of the BFD target vector. The default is m68k_coff_vec.
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TARGET_NAME
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The user visible target name. The default is "coff-m68k".
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NAMES_HAVE_UNDERSCORE
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Whether symbol names have an underscore.
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ONLY_DECLARE_RELOCS
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Only declare the relocation howto array. Don't actually compile
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it. The actual array will be picked up in another version of the
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file.
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STATIC_RELOCS
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Make the relocation howto array, and associated functions, static.
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COFF_COMMON_ADDEND
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If this is defined, then, for a relocation against a common
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symbol, the object file holds the value (the size) of the common
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symbol. If this is not defined, then, for a relocation against a
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common symbol, the object file holds zero. */
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#define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
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#ifndef COFF_PAGE_SIZE
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/* The page size is a guess based on ELF. */
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#define COFF_PAGE_SIZE 0x2000
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#endif
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#ifndef COFF_COMMON_ADDEND
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#define RELOC_SPECIAL_FN 0
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#else
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static bfd_reloc_status_type m68kcoff_common_addend_special_fn
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(bfd *, arelent *, asymbol *, void *, asection *, bfd *, char **);
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#define RELOC_SPECIAL_FN m68kcoff_common_addend_special_fn
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#endif
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static bfd_boolean m68k_coff_is_local_label_name (bfd *, const char *);
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/* On the delta, a symbol starting with L% is local. We won't see
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such a symbol on other platforms, so it should be safe to always
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consider it local here. */
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static bfd_boolean
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m68k_coff_is_local_label_name (bfd *abfd, const char *name)
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{
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if (name[0] == 'L' && name[1] == '%')
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return TRUE;
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return _bfd_coff_is_local_label_name (abfd, name);
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}
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#ifndef STATIC_RELOCS
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/* Clean up namespace. */
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#define m68kcoff_howto_table _bfd_m68kcoff_howto_table
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#define m68k_rtype2howto _bfd_m68kcoff_rtype2howto
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#define m68k_howto2rtype _bfd_m68kcoff_howto2rtype
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#define m68k_reloc_type_lookup _bfd_m68kcoff_reloc_type_lookup
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#define m68k_reloc_name_lookup _bfd_m68kcoff_reloc_name_lookup
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#endif
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#ifdef ONLY_DECLARE_RELOCS
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extern reloc_howto_type m68kcoff_howto_table[];
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#else
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#ifdef STATIC_RELOCS
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static
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#endif
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reloc_howto_type m68kcoff_howto_table[] =
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{
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HOWTO (R_RELBYTE, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "8", TRUE, 0x000000ff,0x000000ff, FALSE),
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HOWTO (R_RELWORD, 0, 1, 16, FALSE, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "16", TRUE, 0x0000ffff,0x0000ffff, FALSE),
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HOWTO (R_RELLONG, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "32", TRUE, 0xffffffff,0xffffffff, FALSE),
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HOWTO (R_PCRBYTE, 0, 0, 8, TRUE, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP8", TRUE, 0x000000ff,0x000000ff, FALSE),
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HOWTO (R_PCRWORD, 0, 1, 16, TRUE, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP16", TRUE, 0x0000ffff,0x0000ffff, FALSE),
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HOWTO (R_PCRLONG, 0, 2, 32, TRUE, 0, complain_overflow_signed, RELOC_SPECIAL_FN, "DISP32", TRUE, 0xffffffff,0xffffffff, FALSE),
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HOWTO (R_RELLONG_NEG, 0, -2, 32, FALSE, 0, complain_overflow_bitfield, RELOC_SPECIAL_FN, "-32", TRUE, 0xffffffff,0xffffffff, FALSE),
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};
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#endif /* not ONLY_DECLARE_RELOCS */
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#ifndef BADMAG
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#define BADMAG(x) M68KBADMAG(x)
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#endif
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#define M68 1 /* Customize coffcode.h */
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/* Turn a howto into a reloc number */
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#ifdef ONLY_DECLARE_RELOCS
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extern void m68k_rtype2howto (arelent *internal, int relocentry);
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extern int m68k_howto2rtype (reloc_howto_type *);
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extern reloc_howto_type * m68k_reloc_type_lookup
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(bfd *, bfd_reloc_code_real_type);
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extern reloc_howto_type * m68k_reloc_name_lookup (bfd *, const char *);
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#else
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#ifdef STATIC_RELOCS
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#define STAT_REL static
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#else
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#define STAT_REL
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#endif
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STAT_REL void m68k_rtype2howto (arelent *, int);
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STAT_REL int m68k_howto2rtype (reloc_howto_type *);
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STAT_REL reloc_howto_type * m68k_reloc_type_lookup (bfd *, bfd_reloc_code_real_type);
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STAT_REL reloc_howto_type * m68k_reloc_name_lookup (bfd *, const char *);
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STAT_REL void
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m68k_rtype2howto (arelent *internal, int relocentry)
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{
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switch (relocentry)
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{
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case R_RELBYTE: internal->howto = m68kcoff_howto_table + 0; break;
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case R_RELWORD: internal->howto = m68kcoff_howto_table + 1; break;
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case R_RELLONG: internal->howto = m68kcoff_howto_table + 2; break;
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case R_PCRBYTE: internal->howto = m68kcoff_howto_table + 3; break;
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case R_PCRWORD: internal->howto = m68kcoff_howto_table + 4; break;
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case R_PCRLONG: internal->howto = m68kcoff_howto_table + 5; break;
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case R_RELLONG_NEG: internal->howto = m68kcoff_howto_table + 6; break;
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default: internal->howto = NULL; break;
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}
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}
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STAT_REL int
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m68k_howto2rtype (reloc_howto_type * internal)
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{
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if (internal->pc_relative)
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{
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switch (internal->bitsize)
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{
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case 32: return R_PCRLONG;
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case 16: return R_PCRWORD;
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case 8: return R_PCRBYTE;
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}
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}
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else
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{
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switch (internal->bitsize)
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{
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case 32: return R_RELLONG;
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case 16: return R_RELWORD;
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case 8: return R_RELBYTE;
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}
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}
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return R_RELLONG;
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}
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STAT_REL reloc_howto_type *
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m68k_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
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bfd_reloc_code_real_type code)
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{
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switch (code)
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{
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default: return NULL;
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case BFD_RELOC_8: return m68kcoff_howto_table + 0;
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case BFD_RELOC_16: return m68kcoff_howto_table + 1;
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case BFD_RELOC_CTOR:
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case BFD_RELOC_32: return m68kcoff_howto_table + 2;
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case BFD_RELOC_8_PCREL: return m68kcoff_howto_table + 3;
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case BFD_RELOC_16_PCREL: return m68kcoff_howto_table + 4;
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case BFD_RELOC_32_PCREL: return m68kcoff_howto_table + 5;
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/* FIXME: There doesn't seem to be a code for R_RELLONG_NEG. */
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}
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/*NOTREACHED*/
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}
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STAT_REL reloc_howto_type *
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m68k_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
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const char *r_name)
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{
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unsigned int i;
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for (i = 0;
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i < sizeof (m68kcoff_howto_table) / sizeof (m68kcoff_howto_table[0]);
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i++)
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if (m68kcoff_howto_table[i].name != NULL
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&& strcasecmp (m68kcoff_howto_table[i].name, r_name) == 0)
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return &m68kcoff_howto_table[i];
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return NULL;
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}
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#endif /* not ONLY_DECLARE_RELOCS */
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#define RTYPE2HOWTO(internal, relocentry) \
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m68k_rtype2howto(internal, (relocentry)->r_type)
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#define SELECT_RELOC(external, internal) \
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external.r_type = m68k_howto2rtype (internal)
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#define coff_bfd_reloc_type_lookup m68k_reloc_type_lookup
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#define coff_bfd_reloc_name_lookup m68k_reloc_name_lookup
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#ifndef COFF_COMMON_ADDEND
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#ifndef coff_rtype_to_howto
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#define coff_rtype_to_howto m68kcoff_rtype_to_howto
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static reloc_howto_type *
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m68kcoff_rtype_to_howto (bfd *abfd ATTRIBUTE_UNUSED,
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asection *sec,
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struct internal_reloc *rel,
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struct coff_link_hash_entry *h ATTRIBUTE_UNUSED,
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struct internal_syment *sym ATTRIBUTE_UNUSED,
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bfd_vma *addendp)
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{
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arelent relent;
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reloc_howto_type *howto;
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relent.howto = NULL;
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RTYPE2HOWTO (&relent, rel);
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howto = relent.howto;
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if (howto != NULL && howto->pc_relative)
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*addendp += sec->vma;
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return howto;
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}
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#endif /* ! defined (coff_rtype_to_howto) */
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#endif /* ! defined (COFF_COMMON_ADDEND) */
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#ifdef COFF_COMMON_ADDEND
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/* If COFF_COMMON_ADDEND is defined, then when using m68k COFF the
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value stored in the .text section for a reference to a common
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symbol is the value itself plus any desired offset. (taken from
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work done by Ian Taylor, Cygnus Support, for I386 COFF). */
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/* If we are producing relocatable output, we need to do some
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adjustments to the object file that are not done by the
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bfd_perform_relocation function. This function is called by every
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reloc type to make any required adjustments. */
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static bfd_reloc_status_type
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m68kcoff_common_addend_special_fn (bfd *abfd,
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arelent *reloc_entry,
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asymbol *symbol,
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void * data,
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asection *input_section ATTRIBUTE_UNUSED,
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bfd *output_bfd,
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char **error_message ATTRIBUTE_UNUSED)
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{
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symvalue diff;
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if (output_bfd == (bfd *) NULL)
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return bfd_reloc_continue;
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if (bfd_is_com_section (symbol->section))
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{
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/* We are relocating a common symbol. The current value in the
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object file is ORIG + OFFSET, where ORIG is the value of the
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common symbol as seen by the object file when it was compiled
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(this may be zero if the symbol was undefined) and OFFSET is
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the offset into the common symbol (normally zero, but may be
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non-zero when referring to a field in a common structure).
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ORIG is the negative of reloc_entry->addend, which is set by
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the CALC_ADDEND macro below. We want to replace the value in
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the object file with NEW + OFFSET, where NEW is the value of
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the common symbol which we are going to put in the final
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object file. NEW is symbol->value. */
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diff = symbol->value + reloc_entry->addend;
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}
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else
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{
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/* For some reason bfd_perform_relocation always effectively
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ignores the addend for a COFF target when producing
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relocatable output. This seems to be always wrong for 386
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COFF, so we handle the addend here instead. */
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diff = reloc_entry->addend;
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}
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#define DOIT(x) \
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x = ((x & ~howto->dst_mask) | (((x & howto->src_mask) + diff) & howto->dst_mask))
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if (diff != 0)
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{
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reloc_howto_type *howto = reloc_entry->howto;
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unsigned char *addr = (unsigned char *) data + reloc_entry->address;
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switch (howto->size)
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{
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case 0:
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{
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char x = bfd_get_8 (abfd, addr);
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DOIT (x);
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bfd_put_8 (abfd, x, addr);
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}
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break;
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case 1:
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{
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short x = bfd_get_16 (abfd, addr);
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DOIT (x);
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bfd_put_16 (abfd, (bfd_vma) x, addr);
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}
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break;
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case 2:
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{
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long x = bfd_get_32 (abfd, addr);
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DOIT (x);
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bfd_put_32 (abfd, (bfd_vma) x, addr);
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}
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break;
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default:
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abort ();
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}
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}
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/* Now let bfd_perform_relocation finish everything up. */
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return bfd_reloc_continue;
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}
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/* Compute the addend of a reloc. If the reloc is to a common symbol,
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the object file contains the value of the common symbol. By the
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time this is called, the linker may be using a different symbol
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from a different object file with a different value. Therefore, we
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hack wildly to locate the original symbol from this file so that we
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can make the correct adjustment. This macro sets coffsym to the
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symbol from the original file, and uses it to set the addend value
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correctly. If this is not a common symbol, the usual addend
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calculation is done, except that an additional tweak is needed for
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PC relative relocs.
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FIXME: This macro refers to symbols and asect; these are from the
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calling function, not the macro arguments. */
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#define CALC_ADDEND(abfd, ptr, reloc, cache_ptr) \
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{ \
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coff_symbol_type *coffsym = (coff_symbol_type *) NULL; \
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if (ptr && bfd_asymbol_bfd (ptr) != abfd) \
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coffsym = (obj_symbols (abfd) \
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+ (cache_ptr->sym_ptr_ptr - symbols)); \
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else if (ptr) \
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coffsym = coff_symbol_from (abfd, ptr); \
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if (coffsym != (coff_symbol_type *) NULL \
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&& coffsym->native->u.syment.n_scnum == 0) \
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cache_ptr->addend = - coffsym->native->u.syment.n_value; \
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else if (ptr && bfd_asymbol_bfd (ptr) == abfd \
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&& ptr->section != (asection *) NULL) \
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cache_ptr->addend = - (ptr->section->vma + ptr->value); \
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else \
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cache_ptr->addend = 0; \
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if (ptr && (reloc.r_type == R_PCRBYTE \
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|| reloc.r_type == R_PCRWORD \
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|| reloc.r_type == R_PCRLONG)) \
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cache_ptr->addend += asect->vma; \
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}
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#ifndef coff_rtype_to_howto
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/* coff-m68k.c uses the special COFF backend linker. We need to
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adjust common symbols. */
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static reloc_howto_type *
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m68kcoff_common_addend_rtype_to_howto (bfd *abfd ATTRIBUTE_UNUSED,
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asection *sec,
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struct internal_reloc *rel,
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struct coff_link_hash_entry *h,
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struct internal_syment *sym,
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bfd_vma *addendp)
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{
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arelent relent;
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reloc_howto_type *howto;
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relent.howto = NULL;
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RTYPE2HOWTO (&relent, rel);
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howto = relent.howto;
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if (howto->pc_relative)
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*addendp += sec->vma;
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if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0)
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{
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/* This is a common symbol. The section contents include the
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size (sym->n_value) as an addend. The relocate_section
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function will be adding in the final value of the symbol. We
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need to subtract out the current size in order to get the
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correct result. */
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BFD_ASSERT (h != NULL);
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*addendp -= sym->n_value;
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}
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/* If the output symbol is common (in which case this must be a
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relocatable link), we need to add in the final size of the
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common symbol. */
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if (h != NULL && h->root.type == bfd_link_hash_common)
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*addendp += h->root.u.c.size;
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return howto;
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}
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#define coff_rtype_to_howto m68kcoff_common_addend_rtype_to_howto
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#endif /* ! defined (coff_rtype_to_howto) */
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#endif /* COFF_COMMON_ADDEND */
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#if !defined ONLY_DECLARE_RELOCS && ! defined STATIC_RELOCS
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/* Given a .data section and a .emreloc in-memory section, store
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relocation information into the .emreloc section which can be
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used at runtime to relocate the section. This is called by the
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linker when the --embedded-relocs switch is used. This is called
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after the add_symbols entry point has been called for all the
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objects, and before the final_link entry point is called. */
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bfd_boolean
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bfd_m68k_coff_create_embedded_relocs (bfd *abfd,
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struct bfd_link_info *info,
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asection *datasec,
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asection *relsec,
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char **errmsg)
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{
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char *extsyms;
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bfd_size_type symesz;
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struct internal_reloc *irel, *irelend;
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bfd_byte *p;
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bfd_size_type amt;
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BFD_ASSERT (! info->relocatable);
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*errmsg = NULL;
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if (datasec->reloc_count == 0)
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return TRUE;
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extsyms = obj_coff_external_syms (abfd);
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symesz = bfd_coff_symesz (abfd);
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||
|
||
irel = _bfd_coff_read_internal_relocs (abfd, datasec, TRUE, NULL, FALSE,
|
||
NULL);
|
||
irelend = irel + datasec->reloc_count;
|
||
|
||
amt = (bfd_size_type) datasec->reloc_count * 12;
|
||
relsec->contents = (bfd_byte *) bfd_alloc (abfd, amt);
|
||
if (relsec->contents == NULL)
|
||
return FALSE;
|
||
|
||
p = relsec->contents;
|
||
|
||
for (; irel < irelend; irel++, p += 12)
|
||
{
|
||
asection *targetsec;
|
||
|
||
/* We are going to write a four byte longword into the runtime
|
||
reloc section. The longword will be the address in the data
|
||
section which must be relocated. It is followed by the name
|
||
of the target section NUL-padded or truncated to 8
|
||
characters. */
|
||
|
||
/* We can only relocate absolute longword relocs at run time. */
|
||
if (irel->r_type != R_RELLONG)
|
||
{
|
||
*errmsg = _("unsupported reloc type");
|
||
bfd_set_error (bfd_error_bad_value);
|
||
return FALSE;
|
||
}
|
||
|
||
if (irel->r_symndx == -1)
|
||
targetsec = bfd_abs_section_ptr;
|
||
else
|
||
{
|
||
struct coff_link_hash_entry *h;
|
||
|
||
h = obj_coff_sym_hashes (abfd)[irel->r_symndx];
|
||
if (h == NULL)
|
||
{
|
||
struct internal_syment isym;
|
||
|
||
bfd_coff_swap_sym_in (abfd, extsyms + symesz * irel->r_symndx,
|
||
&isym);
|
||
targetsec = coff_section_from_bfd_index (abfd, isym.n_scnum);
|
||
}
|
||
else if (h->root.type == bfd_link_hash_defined
|
||
|| h->root.type == bfd_link_hash_defweak)
|
||
targetsec = h->root.u.def.section;
|
||
else
|
||
targetsec = NULL;
|
||
}
|
||
|
||
bfd_put_32 (abfd,
|
||
(irel->r_vaddr - datasec->vma + datasec->output_offset), p);
|
||
memset (p + 4, 0, 8);
|
||
if (targetsec != NULL)
|
||
strncpy ((char *) p + 4, targetsec->output_section->name, 8);
|
||
}
|
||
|
||
return TRUE;
|
||
}
|
||
#endif /* neither ONLY_DECLARE_RELOCS not STATIC_RELOCS */
|
||
|
||
#define coff_bfd_is_local_label_name m68k_coff_is_local_label_name
|
||
|
||
#define coff_relocate_section _bfd_coff_generic_relocate_section
|
||
|
||
#ifndef bfd_pe_print_pdata
|
||
#define bfd_pe_print_pdata NULL
|
||
#endif
|
||
|
||
#include "coffcode.h"
|
||
|
||
#ifndef TARGET_SYM
|
||
#define TARGET_SYM m68k_coff_vec
|
||
#endif
|
||
|
||
#ifndef TARGET_NAME
|
||
#define TARGET_NAME "coff-m68k"
|
||
#endif
|
||
|
||
#ifdef NAMES_HAVE_UNDERSCORE
|
||
CREATE_BIG_COFF_TARGET_VEC (TARGET_SYM, TARGET_NAME, D_PAGED, 0, '_', NULL, COFF_SWAP_TABLE)
|
||
#else
|
||
CREATE_BIG_COFF_TARGET_VEC (TARGET_SYM, TARGET_NAME, D_PAGED, 0, 0, NULL, COFF_SWAP_TABLE)
|
||
#endif
|