# This shell script emits a C file. -*- C -*-
# Copyright (C) 2000-2020 Free Software Foundation, Inc.
# Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em
#
# This file is part of the GNU Binutils.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
# MA 02110-1301, USA.
# This file is sourced from elf.em, and defines some extra routines for m68k
# embedded systems using ELF and for some other systems using m68k ELF. While
# it is sourced from elf.em for all m68k ELF configurations, here we include
# only the features we want depending on the configuration.
case ${target} in
m68*-*-elf)
echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c
;;
esac
case ${target} in
*-linux*)
# Don't use multi-GOT by default due to glibc linker's assumption
# that GOT pointer points to GOT[0].
# got_handling_target_default=GOT_HANDLING_MULTIGOT
got_handling_target_default=GOT_HANDLING_SINGLE
;;
*)
got_handling_target_default=GOT_HANDLING_SINGLE
;;
esac
fragment <<EOF
#include "elf32-m68k.h"
#define GOT_HANDLING_SINGLE (0)
#define GOT_HANDLING_NEGATIVE (1)
#define GOT_HANDLING_MULTIGOT (2)
#define GOT_HANDLING_TARGET_DEFAULT ${got_handling_target_default}
/* How to generate GOT. */
static int got_handling = GOT_HANDLING_DEFAULT;
#ifdef SUPPORT_EMBEDDED_RELOCS
static void check_sections (bfd *, asection *, void *);
#endif
/* This function is run after all the input files have been opened. */
static void
m68k_elf_after_open (void)
{
/* Call the standard elf routine. */
gld${EMULATION_NAME}_after_open ();
#ifdef SUPPORT_EMBEDDED_RELOCS
if (command_line.embedded_relocs
&& (!bfd_link_relocatable (&link_info)))
{
bfd *abfd;
/* In the embedded relocs mode we create a .emreloc section for each
input file with a nonzero .data section. The BFD backend will fill in
these sections with magic numbers which can be used to relocate the
data section at run time. */
for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link.next)
{
asection *datasec;
if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
einfo (_("%F%P: %pB: all input objects must be ELF "
"for --embedded-relocs\n"));
datasec = bfd_get_section_by_name (abfd, ".data");
/* Note that we assume that the reloc_count field has already
been set up. We could call bfd_get_reloc_upper_bound, but
that returns the size of a memory buffer rather than a reloc
count. We do not want to call bfd_canonicalize_reloc,
because although it would always work it would force us to
read in the relocs into BFD canonical form, which would waste
a significant amount of time and memory. */
if (datasec != NULL && datasec->reloc_count > 0)
{
asection *relsec;
relsec = bfd_make_section_with_flags (abfd, ".emreloc",
(SEC_ALLOC
| SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_IN_MEMORY));
if (relsec == NULL
|| !bfd_set_section_alignment (relsec, 2)
|| !bfd_set_section_size (relsec, datasec->reloc_count * 12))
einfo (_("%F%P: %pB: can not create .emreloc section: %E\n"));
}
/* Double check that all other data sections are empty, as is
required for embedded PIC code. */
bfd_map_over_sections (abfd, check_sections, datasec);
}
}
#endif /* SUPPORT_EMBEDDED_RELOCS */
}
#ifdef SUPPORT_EMBEDDED_RELOCS
/* Check that of the data sections, only the .data section has
relocs. This is called via bfd_map_over_sections. */
static void
check_sections (bfd *abfd, asection *sec, void *datasec)
{
if ((bfd_section_flags (sec) & SEC_DATA)
&& sec != datasec
&& sec->reloc_count != 0)
einfo (_("%X%P: %pB: section %s has relocs; can not use --embedded-relocs\n"),
abfd, bfd_section_name (sec));
}
#endif /* SUPPORT_EMBEDDED_RELOCS */
/* This function is called after the section sizes and offsets have
been set. */
static void
m68k_elf_after_allocation (void)
{
/* Call the standard elf routine. */
gld${EMULATION_NAME}_after_allocation ();
#ifdef SUPPORT_EMBEDDED_RELOCS
if (command_line.embedded_relocs
&& (!bfd_link_relocatable (&link_info)))
{
bfd *abfd;
/* If we are generating embedded relocs, call a special BFD backend
routine to do the work. */
for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link.next)
{
asection *datasec, *relsec;
char *errmsg;
datasec = bfd_get_section_by_name (abfd, ".data");
if (datasec == NULL || datasec->reloc_count == 0)
continue;
relsec = bfd_get_section_by_name (abfd, ".emreloc");
ASSERT (relsec != NULL);
if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
{
if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info,
datasec, relsec,
&errmsg))
{
if (errmsg == NULL)
einfo (_("%X%P: %pB: can not create "
"runtime reloc information: %E\n"),
abfd);
else
einfo (_("%X%P: %pB: can not create "
"runtime reloc information: %s\n"),
abfd, errmsg);
}
}
else
abort ();
}
}
#endif /* SUPPORT_EMBEDDED_RELOCS */
}
/* This is a convenient point to tell BFD about target specific flags.
After the output has been created, but before inputs are read. */
static void
elf_m68k_create_output_section_statements (void)
{
bfd_elf_m68k_set_target_options (&link_info, got_handling);
}
EOF
# Define some shell vars to insert bits of code into the standard elf
# parse_args and list_options functions.
#
PARSE_AND_LIST_PROLOGUE='
#define OPTION_GOT 301
'
PARSE_AND_LIST_LONGOPTS='
{ "got", required_argument, NULL, OPTION_GOT},
'
PARSE_AND_LIST_OPTIONS='
fprintf (file, _(" --got=<type> Specify GOT handling scheme\n"));
'
PARSE_AND_LIST_ARGS_CASES='
case OPTION_GOT:
if (strcmp (optarg, "target") == 0)
got_handling = GOT_HANDLING_TARGET_DEFAULT;
else if (strcmp (optarg, "single") == 0)
got_handling = 0;
else if (strcmp (optarg, "negative") == 0)
got_handling = 1;
else if (strcmp (optarg, "multigot") == 0)
got_handling = 2;
else
einfo (_("%P: unrecognized --got argument '\''%s'\''\n"), optarg);
break;
'
# We have our own after_open and after_allocation functions, but they call
# the standard routines, so give them a different name.
LDEMUL_AFTER_OPEN=m68k_elf_after_open
LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=elf_m68k_create_output_section_statements