binutils-gdb/ld/emultempl/cskyelf.em
Alan Modra b209b5a6b8 SHF_LINK_ORDER fixup_link_order in ld
This moves the SHF_LINK_ORDER sorting from bfd_elf_final_link to
the linker which means generic ELF targets now support SHF_LINK_ORDER
and  we cope with odd cases that require resizing of output sections.
The patch also fixes two bugs in the current implementation,
introduced by commit cd6d537c48.  The pattern test used by that
commit meant that sections matching something like
"*(.IA_64.unwind* .gnu.linkonce.ia64unw.*)" would not properly sort a
mix of sections matching the two wildcards.  That commit also assumed
a stable qsort.

bfd/
	PR 27160
	* section.c (struct bfd_section): Remove pattern field.
	(BFD_FAKE_SECTION): Adjust to suit.
	* bfd-in2.h: Regenerate.
	* elflink.c (compare_link_order, elf_fixup_link_order): Delete.
	(bfd_elf_final_link): Don't call elf_fixup_link_order.
ld/
	PR 27160
	* ldlang.h (lang_output_section_statement_type): Add data field.
	(lang_input_section_type, lang_section_bst_type): Add pattern field.
	(statement_list): Declare.
	(lang_add_section): Adjust prototype.
	* emultempl/aarch64elf.em: Adjust lang_add_section calls.
	* emultempl/armelf.em: Likewise.
	* emultempl/beos.em: Likewise.
	* emultempl/cskyelf.em: Likewise.
	* emultempl/hppaelf.em: Likewise.
	* emultempl/m68hc1xelf.em: Likewise.
	* emultempl/metagelf.em: Likewise.
	* emultempl/mipself.em: Likewise.
	* emultempl/mmo.em: Likewise.
	* emultempl/msp430.em: Likewise.
	* emultempl/nios2elf.em: Likewise.
	* emultempl/pe.em: Likewise.
	* emultempl/pep.em: Likewise.
	* emultempl/ppc64elf.em: Likewise.
	* emultempl/spuelf.em: Likewise.
	* emultempl/vms.em: Likewise.
	* ldelf.c: Likewise.
	* ldelfgen.c: Include ldctor.h.
	(struct os_sections): New.
	(add_link_order_input_section, link_order_scan): New functions.
	(compare_link_order, fixup_link_order): New functions.
	(ldelf_map_segments): Call link_order_scan and fixup_link_order.
	* ldlang.c (statement_list): Make global.
	(output_section_callback_fast): Save pattern in tree node.
	(lang_add_section): Add pattern parameter, save in lang_input_section.
	(output_section_callback_tree_to_list): Adjust lang_add_section calls.
	(lang_insert_orphan, output_section_callback): Likewise.
	(ldlang_place_orphan): Likewise.
	(gc_section_callback): Don't set section->pattern
	* testsuite/ld-elf/pr26256-2a.d: Don't xfail generic.
	* testsuite/ld-elf/pr26256-3b.d: Likewise.
	* testsuite/ld-elf/pr26256-2b.d: Likewise.  notarget xgate.
2021-01-13 22:06:02 +10:30

338 lines
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# This shell script emits a C file. -*- C -*-
# Copyright (C) 2013-2021 Free Software Foundation, Inc.
#
# This file is part of 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 extra C-SKY ELF
# specific routines.
#
fragment <<EOF
#include "ldctor.h"
#include "elf/csky.h"
#include "elf32-csky.h"
/* To use branch stub or not. */
extern bfd_boolean use_branch_stub;
/* Fake input file for stubs. */
static lang_input_statement_type *stub_file;
/* Whether we need to call gldcsky_layout_sections_again. */
static int need_laying_out = 0;
/* Maximum size of a group of input sections that can be handled by
one stub section. A value of +/-1 indicates the bfd back-end
should use a suitable default size. */
static bfd_signed_vma group_size = 1;
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 bfd_boolean
hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
{
lang_statement_union_type *l;
bfd_boolean ret;
for (l = *lp; l != NULL; lp = &l->header.next, l = *lp)
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 (l->input_section.section == info->input_section)
{
/* We've found our section. Insert the stub immediately
after its associated input section. */
*(info->add.tail) = l->header.next;
l->header.next = info->add.head;
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;
}
EOF
case ${target} in
csky-*-linux-*)
fragment <<EOF
static void
csky_elf_before_parse (void)
{
use_branch_stub = FALSE;
gld${EMULATION_NAME}_before_parse ();
}
EOF
;;
esac
fragment <<EOF
/* 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
csky_elf_create_output_section_statements (void)
{
if (!(bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour
&& elf_object_id (link_info.output_bfd) == CSKY_ELF_DATA))
use_branch_stub = FALSE;
/* If don't use branch stub, just do not emit stub_file. */
if (!use_branch_stub)
return;
stub_file = lang_add_input_file ("linker stubs",
lang_input_file_is_fake_enum, NULL);
stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
if (stub_file->the_bfd == NULL
|| !bfd_set_arch_mach (stub_file->the_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;
}
stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
ldlang_add_file (stub_file);
}
/* Call-back for elf32_csky_size_stubs. */
/* Create a new stub section, and arrange for it to be linked
immediately after INPUT_SECTION. */
static asection *
elf32_csky_add_stub_section (const char *stub_sec_name,
asection *input_section)
{
asection *stub_sec;
flagword flags;
asection *output_section;
const char *secname;
lang_output_section_statement_type *os;
struct hook_stub_info info;
flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
| SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
stub_sec_name, flags);
if (stub_sec == NULL)
goto err_ret;
bfd_set_section_alignment (stub_sec, 3);
output_section = input_section->output_section;
secname = bfd_section_name (output_section);
os = lang_output_section_find (secname);
info.input_section = input_section;
lang_list_init (&info.add);
lang_add_section (&info.add, stub_sec, NULL, NULL, os);
if (info.add.head == NULL)
goto err_ret;
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;
}
/* Another call-back for elf_csky_size_stubs. */
static void
gldcsky_layout_sections_again (void)
{
/* If we have changed sizes of the stub sections, then we need
to recalculate all the section offsets. This may mean we need to
add even more stubs. */
ldelf_map_segments (TRUE);
need_laying_out = -1;
}
static void
build_section_lists (lang_statement_union_type *statement)
{
if (statement->header.type == lang_input_section_enum)
{
asection *i = statement->input_section.section;
if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
&& (i->flags & SEC_EXCLUDE) == 0
&& i->output_section != NULL
&& i->output_section->owner == link_info.output_bfd)
elf32_csky_next_input_section (&link_info, i);
}
}
static void
gld${EMULATION_NAME}_after_allocation (void)
{
/* bfd_elf32_discard_info just plays with debugging sections,
ie. doesn't affect any code, so we can delay resizing the
sections. It's likely we'll resize everything in the process of
adding stubs. */
if (bfd_elf_discard_info (link_info.output_bfd, &link_info))
need_laying_out = 1;
/* If generating a relocatable output file, then we don't
have to examine the relocs. */
if (stub_file != NULL && !bfd_link_relocatable (&link_info))
{
int ret = elf32_csky_setup_section_lists (link_info.output_bfd,
&link_info);
if (ret < 0)
{
einfo (_("%X%P: could not compute sections lists for stub generation: %E\n"));
return;
}
else if (ret != 0)
{
lang_for_each_statement (build_section_lists);
/* Call into the BFD backend to do the real work. */
if (! elf32_csky_size_stubs (link_info.output_bfd,
stub_file->the_bfd,
&link_info,
group_size,
&elf32_csky_add_stub_section,
&gldcsky_layout_sections_again))
{
einfo (_("%X%P: cannot size stub section: %E\n"));
return;
}
}
}
if (need_laying_out != -1)
ldelf_map_segments (need_laying_out);
}
static void
gld${EMULATION_NAME}_finish (void)
{
if (stub_file != NULL
&& !bfd_link_relocatable (&link_info)
&& stub_file->the_bfd->sections != NULL
&& !elf32_csky_build_stubs (&link_info))
einfo (_("%X%P: cannot build stubs: %E\n"));
finish_default ();
}
EOF
# This code gets inserted into the generic elf32.sc linker script
# and allows us to define our own command line switches.
PARSE_AND_LIST_PROLOGUE='
#define OPTION_BRANCH_STUB 301
#define OPTION_NO_BRANCH_STUB 302
#define OPTION_STUBGROUP_SIZE 303
'
PARSE_AND_LIST_LONGOPTS='
{"branch-stub", no_argument, NULL, OPTION_BRANCH_STUB},
{"no-branch-stub", no_argument, NULL, OPTION_NO_BRANCH_STUB},
{"stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE},
'
PARSE_AND_LIST_OPTIONS='
fprintf (file, _(" --[no-]branch-stub "
"Disable/enable use of stubs to expand branch\n"
" "
" instructions that cannot reach the target.\n"));
fprintf (file, _(" --stub-group-size=N "
"Maximum size of a group of input sections\n"
" "
" handled by one stub section.\n"));
'
PARSE_AND_LIST_ARGS_CASES='
case OPTION_BRANCH_STUB:
use_branch_stub = TRUE;
break;
case OPTION_NO_BRANCH_STUB:
use_branch_stub = FALSE;
break;
case OPTION_STUBGROUP_SIZE:
{
const char *end;
group_size = bfd_scan_vma (optarg, &end, 0);
if (*end)
einfo (_("%F%P: invalid number `%s'\''\n"), optarg);
}
break;
'
case ${target} in
csky-*-linux-*) LDEMUL_BEFORE_PARSE=csky_elf_before_parse ;;
esac
LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=csky_elf_create_output_section_statements
LDEMUL_FINISH=gld${EMULATION_NAME}_finish