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# This shell script emits a C file. -*- C -*-
# Copyright (C) 2004-2023 Free Software Foundation, Inc.
#
# 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.
case ${target} in
*-*-*gnu*)
gnu_target=true
;;
*)
gnu_target=false
;;
esac
fragment <<EOF
#include "ldctor.h"
#include "elf/mips.h"
#include "elfxx-mips.h"
#define is_mips_elf(bfd) \
(bfd_get_flavour (bfd) == bfd_target_elf_flavour \
&& elf_tdata (bfd) != NULL \
&& elf_object_id (bfd) == MIPS_ELF_DATA)
/* Fake input file for stubs. */
static lang_input_statement_type *stub_file;
static bfd *stub_bfd;
static bool insn32;
static bool ignore_branch_isa;
static bool compact_branches;
struct hook_stub_info
{
lang_statement_list_type add;
asection *input_section;
};
/* Traverse the linker tree to find the spot where the stub goes. */
static bool
hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
{
lang_statement_union_type *l;
bool ret;
for (; (l = *lp) != NULL; lp = &l->header.next)
{
switch (l->header.type)
{
case lang_constructors_statement_enum:
ret = hook_in_stub (info, &constructor_list.head);
if (ret)
return ret;
break;
case lang_output_section_statement_enum:
ret = hook_in_stub (info,
&l->output_section_statement.children.head);
if (ret)
return ret;
break;
case lang_wild_statement_enum:
ret = hook_in_stub (info, &l->wild_statement.children.head);
if (ret)
return ret;
break;
case lang_group_statement_enum:
ret = hook_in_stub (info, &l->group_statement.children.head);
if (ret)
return ret;
break;
case lang_input_section_enum:
if (info->input_section == NULL
|| l->input_section.section == info->input_section)
{
/* We've found our section. Insert the stub immediately
before its associated input section. */
*lp = info->add.head;
*(info->add.tail) = l;
return true;
}
break;
case lang_data_statement_enum:
case lang_reloc_statement_enum:
case lang_object_symbols_statement_enum:
case lang_output_statement_enum:
case lang_target_statement_enum:
case lang_input_statement_enum:
case lang_assignment_statement_enum:
case lang_padding_statement_enum:
case lang_address_statement_enum:
case lang_fill_statement_enum:
break;
default:
FAIL ();
break;
}
}
return false;
}
/* Create a new stub section called STUB_SEC_NAME and arrange for it to
be linked in OUTPUT_SECTION. The section should go at the beginning of
OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately
before INPUT_SECTION. */
static asection *
mips_add_stub_section (const char *stub_sec_name, asection *input_section,
asection *output_section)
{
asection *stub_sec;
flagword flags;
lang_output_section_statement_type *os;
struct hook_stub_info info;
/* PR 12845: If the input section has been garbage collected it will
not have its output section set to *ABS*. */
if (bfd_is_abs_section (output_section))
return NULL;
/* Create the stub file, if we haven't already. */
if (stub_file == NULL)
{
stub_file = lang_add_input_file ("linker stubs",
lang_input_file_is_fake_enum,
NULL);
stub_bfd = bfd_create ("linker stubs", link_info.output_bfd);
if (stub_bfd == NULL
|| !bfd_set_arch_mach (stub_bfd,
bfd_get_arch (link_info.output_bfd),
bfd_get_mach (link_info.output_bfd)))
{
einfo (_("%F%P: can not create BFD: %E\n"));
return NULL;
}
stub_bfd->flags |= BFD_LINKER_CREATED;
stub_file->the_bfd = stub_bfd;
ldlang_add_file (stub_file);
}
/* Create the section. */
stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name);
if (stub_sec == NULL)
goto err_ret;
/* Set the flags. */
flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
| SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
if (!bfd_set_section_flags (stub_sec, flags))
goto err_ret;
os = lang_output_section_get (output_section);
/* Initialize a statement list that contains only the new statement. */
lang_list_init (&info.add);
lang_add_section (&info.add, stub_sec, NULL, NULL, os);
if (info.add.head == NULL)
goto err_ret;
/* Insert the new statement in the appropriate place. */
info.input_section = input_section;
if (hook_in_stub (&info, &os->children.head))
return stub_sec;
err_ret:
einfo (_("%X%P: can not make stub section: %E\n"));
return NULL;
}
/* This is called before the input files are opened. */
static void
mips_create_output_section_statements (void)
{
struct elf_link_hash_table *htab;
htab = elf_hash_table (&link_info);
if (is_elf_hash_table (&htab->root) && is_mips_elf (link_info.output_bfd))
_bfd_mips_elf_linker_flags (&link_info, insn32, ignore_branch_isa,
${gnu_target});
if (is_mips_elf (link_info.output_bfd))
{
_bfd_mips_elf_compact_branches (&link_info, compact_branches);
_bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section);
}
}
/* This is called after we have merged the private data of the input bfds. */
static void
mips_before_allocation (void)
{
if (is_mips_elf (link_info.output_bfd))
{
flagword flags;
flags = elf_elfheader (link_info.output_bfd)->e_flags;
if (!bfd_link_pic (&link_info)
&& !link_info.nocopyreloc
&& (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC)
_bfd_mips_elf_use_plts_and_copy_relocs (&link_info);
}
gld${EMULATION_NAME}_before_allocation ();
}
EOF
# Define some shell vars to insert bits of code into the standard elf
# parse_args and list_options functions.
#
PARSE_AND_LIST_PROLOGUE='
enum
{
OPTION_INSN32 = 301,
OPTION_NO_INSN32,
OPTION_IGNORE_BRANCH_ISA,
OPTION_NO_IGNORE_BRANCH_ISA,
OPTION_COMPACT_BRANCHES,
OPTION_NO_COMPACT_BRANCHES
};
'
PARSE_AND_LIST_LONGOPTS='
{ "insn32", no_argument, NULL, OPTION_INSN32 },
{ "no-insn32", no_argument, NULL, OPTION_NO_INSN32 },
{ "ignore-branch-isa", no_argument, NULL, OPTION_IGNORE_BRANCH_ISA },
{ "no-ignore-branch-isa", no_argument, NULL, OPTION_NO_IGNORE_BRANCH_ISA },
{ "compact-branches", no_argument, NULL, OPTION_COMPACT_BRANCHES },
{ "no-compact-branches", no_argument, NULL, OPTION_NO_COMPACT_BRANCHES },
'
PARSE_AND_LIST_OPTIONS='
fprintf (file, _("\
--insn32 Only generate 32-bit microMIPS instructions\n"
));
fprintf (file, _("\
--no-insn32 Generate all microMIPS instructions\n"
));
fprintf (file, _("\
--ignore-branch-isa Accept invalid branch relocations requiring\n\
an ISA mode switch\n"
));
fprintf (file, _("\
--no-ignore-branch-isa Reject invalid branch relocations requiring\n\
an ISA mode switch\n"
));
fprintf (file, _("\
--compact-branches Generate compact branches/jumps for MIPS R6\n"
));
fprintf (file, _("\
--no-compact-branches Generate delay slot branches/jumps for MIPS R6\n"
));
'
PARSE_AND_LIST_ARGS_CASES='
case OPTION_INSN32:
insn32 = true;
break;
case OPTION_NO_INSN32:
insn32 = false;
break;
case OPTION_IGNORE_BRANCH_ISA:
ignore_branch_isa = true;
break;
case OPTION_NO_IGNORE_BRANCH_ISA:
ignore_branch_isa = false;
break;
case OPTION_COMPACT_BRANCHES:
compact_branches = true;
break;
case OPTION_NO_COMPACT_BRANCHES:
compact_branches = false;
break;
'
LDEMUL_BEFORE_ALLOCATION=mips_before_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements
|
