Re: PATCH: Enable 2 stage linking and support "ld -r" on mixed IR objects in BFD linker

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Fri, Dec 10, 2010 at 5:27 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> Hi,
>
> This patch enables 2 stage linking and supports "ld -r" on mixed IR
> objects in BFD linker. It provides transparent LTO support in BFD
> linker. ?No GCC changes are required.
>
> Any comments?
>
> Thanks.
>

The linker spec is at:

http://www.kernel.org/pub/linux/devel/gcc/lto/mixed-IR/mixed-IR.pdf

BFD linker in the Linux binutils will have the full and transparent LTO
support.


H.J.
--
> ---
> bfd/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* bfd.c (bfd_lto_object_type): New.
> ? ? ? ?(BFD_PLUGIN): Likewise.
> ? ? ? ?(BFD_PLUGIN_DUMMY): Likewise.
> ? ? ? ?(bfd_group_signature): Likewise.
> ? ? ? ?(BFD_FLAGS_SAVED): Add BFD_PLUGIN and BFD_PLUGIN_DUMMY.
> ? ? ? ?(BFD_FLAGS_FOR_BFD_USE_MASK): Likewise.
> ? ? ? ?(bfd): Add object_only_section and lto_type.
>
> ? ? ? ?* elf.c (special_sections_g): Add ".gnu.lto" and .gnu_object_only.
> ? ? ? ?(_bfd_elf_get_special_section): Allow `_' as separator.
>
> ? ? ? ?* elflink.c (elf_link_add_archive_symbols): Remove subsbfd.
>
> ? ? ? ?* format.c (bfd_set_lto_type): New.
> ? ? ? ?(bfd_check_format_matches): Use it.
>
> ? ? ? ?* section.c (GNU_OBJECT_ONLY_SECTION_NAME): New.
>
> ? ? ? ?* bfd-in2.h: Regenerated.
>
> binutils/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* objcopy.c (group_signature): Removed.
> ? ? ? ?(is_strip_section): Replace group_signature with
> ? ? ? ?bfd_group_signature.
> ? ? ? ?(setup_section): Likewise.
>
> ? ? ? ?* readelf.c (get_section_type_name): Handle SHT_GNU_OBJECT_ONLY.
>
> gas/testsuite/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* gas/elf/elf.exp: Run section9.
>
> ? ? ? ?* gas/elf/section9.d: New.
> ? ? ? ?* gas/elf/section9.s: Likewise.
>
> include/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?* bfdlink.h (bfd_link_info): Add emit_gnu_object_only and
> ? ? ? ?emitting_gnu_object_only.
>
> include/elf/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* common.h (SHT_GNU_OBJECT_ONLY): New.
>
> ld/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* ldfile.c: Updated for 2 stage linking and support for mixed
> ? ? ? ?IR/non-IR objects.
> ? ? ? ?* ldlang.c: Likewise.
>
> ? ? ? ?* ldlang.h (lang_input_statement_struct): Add stage1.
> ? ? ? ?(lang_init): Take a bfd_boolean argument.
> ? ? ? ?(cmdline_enum_type): New.
> ? ? ? ?(cmdline_header_type): Likewise.
> ? ? ? ?(cmdline_input_statement_type): Likewise.
> ? ? ? ?(cmdline_file_type): Likewise.
> ? ? ? ?(cmdline_bfd_type): Likewise.
> ? ? ? ?(cmdline_union_type): Likewise.
> ? ? ? ?(cmdline_list_type): Likewise.
> ? ? ? ?(cmdline_option_append): Likewise.
> ? ? ? ?(cmdline_option_insert_claimed_output): Likewise.
> ? ? ? ?(cmdline_set_next_claimed_output): Likewise.
> ? ? ? ?(cmdline_claimed_archive_member_list_append): Likewise.
> ? ? ? ?(cmdline_emit_object_only_section): Likewise.
> ? ? ? ?(cmdline_check_object_only_section): Likewise.
> ? ? ? ?(cmdline_remove_object_only_files): Likewise.
>
> ? ? ? ?* ldmain.c (main): Pass FALSE to lang_init. ?Use
> ? ? ? ?ld_parse_linker_script. ?Set link_info.output_bfd to NULL
> ? ? ? ?after close. ?Call cmdline_emit_object_only_section if needed.
> ? ? ? ?(ld_parse_linker_script): New.
> ? ? ? ?(add_archive_element): Updated for 2 stage linking and support
> ? ? ? ?for mixed IR/non-IR objects.
>
> ? ? ? ?* ldmain.h (ld_parse_linker_script): New.
>
> ? ? ? ?* plugin.c (IRONLY_SUFFIX_LEN): Removed.
> ? ? ? ?(plugin_opt_plugin_arg): Ignore -pass-through=.
> ? ? ? ?(plugin_get_ir_dummy_bfd): Set BFD_PLUGIN_DUMMY on dummy IR
> ? ? ? ?input.
> ? ? ? ?(is_ir_dummy_bfd): Check BFD_PLUGIN_DUMMY.
> ? ? ? ?(get_symbols): Re-indent.
> ? ? ? ?(add_input_file): Replace lang_add_input_file with
> ? ? ? ?cmdline_list_insert_claimed_output.
> ? ? ? ?(add_input_library): Likewise
>
> ? ? ? ?* emultempl/elf32.em (orphan_init_done): Moved out of
> ? ? ? ?gld${EMULATION_NAME}_place_orphan.
> ? ? ? ?(hold): Likewise.
> ? ? ? ?(gld${EMULATION_NAME}_finish): New.
> ? ? ? ?(ld_${EMULATION_NAME}_emulation): Use gld${EMULATION_NAME}_finish.
>
> ? ? ? ?* scripttempl/armbpabi.sc: Also discard .gnu_object_only
> ? ? ? ?sections.
> ? ? ? ?* scripttempl/elf.sc: Likewise.
> ? ? ? ?* scripttempl/elf32sh-symbian.sc: Likewise.
> ? ? ? ?* scripttempl/elf64hppa.sc: Likewise.
> ? ? ? ?* scripttempl/elfxtensa.sc: Likewise.
> ? ? ? ?* scripttempl/mep.sc: Likewise.
> ? ? ? ?* scripttempl/pe.sc: Likewise.
> ? ? ? ?* scripttempl/pep.sc: Likewise.
>
> ld/testsuite/
>
> 2010-12-10 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR ld/12248
> ? ? ? ?PR ld/12277
> ? ? ? ?PR ld/12291
> ? ? ? ?* ld-plugin/func1p.c: New.
> ? ? ? ?* ld-plugin/func2.c: Likewise.
> ? ? ? ?* ld-plugin/func2i.c: Likewise.
> ? ? ? ?* ld-plugin/func3h.c: Likewise.
>
> ? ? ? ?* ld-plugin/plugin.exp: Add object files for symbols claimed
> ? ? ? ?or created by testplugin.
> ? ? ? ?* ld-plugin/plugin-7.d: Updated.
> ? ? ? ?* ld-plugin/plugin-8.d: Likewise.
> ? ? ? ?* ld-plugin/plugin-9.d: Likewise.
>