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binutils-gdb/ld/ldelfgen.h

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Move elf32.em and elf-generic.em functions Many ELF linker targets support multiple "emulations" and thus have multiple copies of elf32.em being compiled and linked into ld. This patch moves much of elf32.em and elf-generic.em into files which will be compiled just once, resulting in a 20% decrease in ld size for --enable-targets=all. * Makefile.am (ALL_EMUL_EXTRA_OFILES): Add ldelf and ldelfgen. (CFILES, HFILES, EXTRA_ld_new_SOURCES): Likewise. * configure.tgt: Formatting. (targ_extra_ofiles): Init to ldelf.o ldelfgen.o, reset to just ldelfgen.o for generic ELF targets, and empty for non-ELF. * emultempl/aarch64elf.em (gldaarch64_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, aarch64_for_each_input_file_wrapper), (aarch64_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/alphaelf.em (alpha_after_parse): Use ldelf_map_segments. * emultempl/armelf.em (gldarm_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, arm_for_each_input_file_wrapper), (arm_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/cr16elf.em (cr16elf_after_parse): Use ldelf_map_segments. * emultempl/crxelf.em (crxelf_after_parse): Likewise. Delete declaration. * emultempl/cskyelf.em (gldcsky_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, csky_for_each_input_file_wrapper), (csky_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/genelf.em: Include ldelfgen.h. (gld${EMULATION_NAME}_before_allocation): Use ldelf_map_segments. * emultempl/hppaelf.em (hppaelf_after_parse): Likewise. (hppaelf_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, hppa_for_each_input_file_wrapper), (hppa_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ia64elf.em (ia64elf_after_parse): Use ldelf_map_segments. * emultempl/m68hc1xelf.em (real_func), (m68hc11_for_each_input_file_wrapper), (m68hc11_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/metagelf.em (metagelf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, metag_for_each_input_file_wrapper), (metag_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mipself.em (real_func), (mips_for_each_input_file_wrapper), (mips_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mmo.em: Don't include elf-bfd.h, do include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/nds32elf.em (nds32_elf_after_parse): Use ldelf_after_parse. (nds32_elf_after_allocation): Comment fix. * emultempl/nios2elf.em (nios2elf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, nios2_for_each_input_file_wrapper), (nios2_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ppc32elf.em (gld${EMULATION_NAME}_load_symbols): Delete declaration. (ppc_recognized_file): Call ldelf_load_symbols. * emultempl/ppc64elf.em (ppc_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, ppc_for_each_input_file_wrapper), (ppc_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. (gld${EMULATION_NAME}_load_symbols): Don't declare. (ppc64_recognized_file): Call ldelf_load_symbols. * emultempl/riscvelf.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/spuelf.em (spu_place_special_section): Use ldelf_place_orphan. * emultempl/tic6xdsbt.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/vms.em: Include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/elf32.em: Remove unnecessary headers, include ldelf.h and ldelfgen.h. Move much of file content to.. * ldelf.c: ..here. New file. * ldelf.h: New file. * emultempl/elf-generic.em: Move gld${EMULATION_NAME}_map_segments.. * ldelfgen.c: ..to here. * ldelfgen.h: New file. * ldlang.c (lang_for_each_input_file): Adjust to only call func on real files. (lang_for_each_file): Likewise. * po/SRC-POTFILES.in: Regenerate. * Makefile.in: Regenerate.
2019-09-09 21:37:35 +08:00
/* Emulation code used by all ELF targets.
Update year range in copyright notice of binutils files
2021-01-01 06:58:58 +08:00
Copyright (C) 1991-2021 Free Software Foundation, Inc.
Move elf32.em and elf-generic.em functions Many ELF linker targets support multiple "emulations" and thus have multiple copies of elf32.em being compiled and linked into ld. This patch moves much of elf32.em and elf-generic.em into files which will be compiled just once, resulting in a 20% decrease in ld size for --enable-targets=all. * Makefile.am (ALL_EMUL_EXTRA_OFILES): Add ldelf and ldelfgen. (CFILES, HFILES, EXTRA_ld_new_SOURCES): Likewise. * configure.tgt: Formatting. (targ_extra_ofiles): Init to ldelf.o ldelfgen.o, reset to just ldelfgen.o for generic ELF targets, and empty for non-ELF. * emultempl/aarch64elf.em (gldaarch64_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, aarch64_for_each_input_file_wrapper), (aarch64_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/alphaelf.em (alpha_after_parse): Use ldelf_map_segments. * emultempl/armelf.em (gldarm_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, arm_for_each_input_file_wrapper), (arm_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/cr16elf.em (cr16elf_after_parse): Use ldelf_map_segments. * emultempl/crxelf.em (crxelf_after_parse): Likewise. Delete declaration. * emultempl/cskyelf.em (gldcsky_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, csky_for_each_input_file_wrapper), (csky_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/genelf.em: Include ldelfgen.h. (gld${EMULATION_NAME}_before_allocation): Use ldelf_map_segments. * emultempl/hppaelf.em (hppaelf_after_parse): Likewise. (hppaelf_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, hppa_for_each_input_file_wrapper), (hppa_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ia64elf.em (ia64elf_after_parse): Use ldelf_map_segments. * emultempl/m68hc1xelf.em (real_func), (m68hc11_for_each_input_file_wrapper), (m68hc11_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/metagelf.em (metagelf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, metag_for_each_input_file_wrapper), (metag_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mipself.em (real_func), (mips_for_each_input_file_wrapper), (mips_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mmo.em: Don't include elf-bfd.h, do include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/nds32elf.em (nds32_elf_after_parse): Use ldelf_after_parse. (nds32_elf_after_allocation): Comment fix. * emultempl/nios2elf.em (nios2elf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, nios2_for_each_input_file_wrapper), (nios2_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ppc32elf.em (gld${EMULATION_NAME}_load_symbols): Delete declaration. (ppc_recognized_file): Call ldelf_load_symbols. * emultempl/ppc64elf.em (ppc_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, ppc_for_each_input_file_wrapper), (ppc_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. (gld${EMULATION_NAME}_load_symbols): Don't declare. (ppc64_recognized_file): Call ldelf_load_symbols. * emultempl/riscvelf.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/spuelf.em (spu_place_special_section): Use ldelf_place_orphan. * emultempl/tic6xdsbt.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/vms.em: Include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/elf32.em: Remove unnecessary headers, include ldelf.h and ldelfgen.h. Move much of file content to.. * ldelf.c: ..here. New file. * ldelf.h: New file. * emultempl/elf-generic.em: Move gld${EMULATION_NAME}_map_segments.. * ldelfgen.c: ..to here. * ldelfgen.h: New file. * ldlang.c (lang_for_each_input_file): Adjust to only call func on real files. (lang_for_each_file): Likewise. * po/SRC-POTFILES.in: Regenerate. * Makefile.in: Regenerate.
2019-09-09 21:37:35 +08:00
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. */
bfd, include, ld, binutils, libctf: CTF should use the dynstr/sym This is embarrassing. The whole point of CTF is that it remains intact even after a binary is stripped, providing a compact mapping from symbols to types for everything in the externally-visible interface of an ELF object: it has connections to the symbol table for that purpose, and to the string table to avoid duplicating symbol names. So it's a shame that the hooks I implemented last year served to hook it up to the .symtab and .strtab, which obviously disappear on strip, leaving any accompanying the CTF dict containing references to strings (and, soon, symbols) which don't exist any more because their containing strtab has been vaporized. The original Solaris design used .dynsym and .dynstr (well, actually, .ldynsym, which has more symbols) which do not disappear. So should we. Thankfully the work we did before serves as guide rails, and adjusting things to use the .dynstr and .dynsym was fast and easy. The only annoyance is that the dynsym is assembled inside elflink.c in a fairly piecemeal fashion, so that the easiest way to get the symbols out was to hook in before every call to swap_symbol_out (we also leave in a hook in front of symbol additions to the .symtab because it seems plausible that we might want to hook them in future too: for now that hook is unused). We adjust things so that rather than being offered a whole hash table of symbols at once, libctf is now given symbols one at a time, with st_name indexes already resolved and pointing at their final .dynstr offsets: it's now up to libctf to resolve these to names as needed using the strtab info we pass it separately. Some bits might be contentious. The ctf_new_dynstr callback takes an elf_internal_sym, and this remains an elf_internal_sym right down through the generic emulation layers into ldelfgen. This is no worse than the elf_sym_strtab we used to pass down, but in the future when we gain non-ELF CTF symtab support we might want to lower the elf_internal_sym to some other representation (perhaps a ctf_link_symbol) in bfd or in ldlang_ctf_new_dynsym. We rename the 'apply_strsym' hooks to 'acquire_strings' instead, becuse they no longer have anything to do with symbols. There are some API changes to pieces of API which are technically public but actually totally unused by anything and/or unused by anything but ld so they can change freely: the ctf_link_symbol gains new fields to allow symbol names to be given as strtab offsets as well as strings, and a symidx so that the symbol index can be passed in. ctf_link_shuffle_syms loses its callback parameter: the idea now is that linkers call the new ctf_link_add_linker_symbol for every symbol in .dynsym, feed in all the strtab entries with ctf_link_add_strtab, and then a call to ctf_link_shuffle_syms will apply both and arrange to use them to reorder the CTF symtab at CTF serialization time (which is coming in the next commit). Inside libctf we have a new preamble flag CTF_F_DYNSTR which is always set in v3-format CTF dicts from this commit forwards: CTF dicts without this flag are associated with .strtab like they used to be, so that old dicts' external strings don't turn to garbage when loaded by new libctf. Dicts with this flag are associated with .dynstr and .dynsym instead. (The flag is not the next in sequence because this commit was written quite late: the missing flags will be filled in by the next commit.) Tests forthcoming in a later commit in this series. bfd/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * elflink.c (elf_finalize_dynstr): Call examine_strtab after dynstr finalization. (elf_link_swap_symbols_out): Don't call it here. Call ctf_new_symbol before swap_symbol_out. (elf_link_output_extsym): Call ctf_new_dynsym before swap_symbol_out. (bfd_elf_final_link): Likewise. * elf.c (swap_out_syms): Pass in bfd_link_info. Call ctf_new_symbol before swap_symbol_out. (_bfd_elf_compute_section_file_positions): Adjust. binutils/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * readelf.c (dump_section_as_ctf): Use .dynsym and .dynstr, not .symtab and .strtab. include/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * bfdlink.h (struct elf_sym_strtab): Replace with... (struct elf_internal_sym): ... this. (struct bfd_link_callbacks) <examine_strtab>: Take only a symstrtab argument. <ctf_new_symbol>: New. <ctf_new_dynsym>: Likewise. * ctf-api.h (struct ctf_link_sym) <st_symidx>: New. <st_nameidx>: Likewise. <st_nameidx_set>: Likewise. (ctf_link_iter_symbol_f): Removed. (ctf_link_shuffle_syms): Remove most parameters, just takes a ctf_dict_t now. (ctf_link_add_linker_symbol): New, split from ctf_link_shuffle_syms. * ctf.h (CTF_F_DYNSTR): New. (CTF_F_MAX): Adjust. ld/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ldelfgen.c (struct ctf_strsym_iter_cb_arg): Rename to... (struct ctf_strtab_iter_cb_arg): ... this, changing fields: <syms>: Remove. <symcount>: Remove. <symstrtab>: Rename to... <strtab>: ... this. (ldelf_ctf_strtab_iter_cb): Adjust. (ldelf_ctf_symbols_iter_cb): Remove. (ldelf_new_dynsym_for_ctf): New, tell libctf about a single symbol. (ldelf_examine_strtab_for_ctf): Rename to... (ldelf_acquire_strings_for_ctf): ... this, only doing the strtab portion and not symbols. * ldelfgen.h: Adjust declarations accordingly. * ldemul.c (ldemul_examine_strtab_for_ctf): Rename to... (ldemul_acquire_strings_for_ctf): ... this. (ldemul_new_dynsym_for_ctf): New. * ldemul.h: Adjust declarations accordingly. * ldlang.c (ldlang_ctf_apply_strsym): Rename to... (ldlang_ctf_acquire_strings): ... this. (ldlang_ctf_new_dynsym): New. (lang_write_ctf): Call ldemul_new_dynsym_for_ctf with NULL to do the actual symbol shuffle. * ldlang.h (struct elf_strtab_hash): Adjust accordingly. * ldmain.c (bfd_link_callbacks): Wire up new/renamed callbacks. libctf/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ctf-link.c (ctf_link_shuffle_syms): Adjust. (ctf_link_add_linker_symbol): New, unimplemented stub. * libctf.ver: Add it. * ctf-create.c (ctf_serialize): Set CTF_F_DYNSTR on newly-serialized dicts. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Check for the flag: open the symtab/strtab if not present, dynsym/dynstr otherwise. * ctf-archive.c (ctf_arc_bufpreamble): New, get the preamble from some arbitrary member of a CTF archive. * ctf-impl.h (ctf_arc_bufpreamble): Declare it.
2020-11-20 21:34:04 +08:00
struct elf_internal_sym;
bfd, ld: add CTF section linking This is quite complicated because the CTF section's contents depend on the final contents of the symtab and strtab, because it has two sections whose contents are shuffled to be in 1:1 correspondence with the symtab, and an internal strtab that gets deduplicated against the ELF strtab (with offsets adjusted to point into the ELF strtab instead). It is also compressed if large enough, so its size depends on its contents! So we cannot construct it as early as most sections: we cannot even *begin* construction until after the symtab and strtab are finalized. Thankfully there is already one section treated similarly: compressed debugging sections: the only differences are that compressed debugging sections have extra handling to deal with their changing name if compressed (CTF sections are always called ".ctf" for now, though we have reserved ".ctf.*" against future use), and that compressed debugging sections have previously-uncompressed content which has to be stashed away for later compression, while CTF sections have no content at all until we generate it (very late). BFD also cannot do the link itself: libctf knows how to do it, and BFD cannot call libctf directly because libctf already depends on bfd for file I/O. So we have to use a pair of callbacks, one, examine_strtab, which allows a caller to examine the symtab and strtab after finalization (called from elf_link_swap_symbols_out(), right before the symtabs are written, and after the strtab has been finalized), and one which actually does the emission (called emit_ctf simply because it is grouped with a bunch of section-specific late-emission function calls at the bottom of bfd_elf_final_link, and a section-specific name seems best for that). emit_ctf is actually called *twice*: once from lang_process if the emulation suggests that this bfd target does not examine the symtab or strtab, and once via a bfd callback if it does. (This means that non-ELF targets still get CTF emitted, even though the late CTF emission stage is never called for them). v2: merged with non-ELF support patch: slight commit message adjustments. v3: do not spend time merging CTF, or crash, if the CTF section is explicitly discarded. Do not try to merge or compress CTF unless linking. v4: add CTF_COMPRESSION_THRESHOLD. Annul the freed input ctf_file_t's after writeout: set SEC_IN_MEMORY on the output contents so a future bfd enhancement knows it could free it. Add SEC_LINKER_CREATED | SEC_KEEP to avoid having to add .ctf to the linker script. Drop now-unnecessary ldlang.h-level elf-bfd.h include and hackery around it. Adapt to elf32.em->elf.em and elf-generic.em->ldelf*.c changes. v5: fix tabdamage. Drop #inclusions in .h files: include in .c files, .em files, and use struct forwards instead. Use bfd_section_is_ctf inline function rather than SECTION_IS_CTF macro. Move a few comments. * Makefile.def (dependencies): all-ld depends on all-libctf. * Makefile.in: Regenerated. include/ * bfdlink.h (elf_strtab_hash): New forward. (elf_sym_strtab): Likewise. (struct bfd_link_callbacks <examine_strtab>): New. (struct bfd_link_callbacks <emit_ctf>): Likewise. bfd/ * elf-bfd.h (bfd_section_is_ctf): New inline function. * elf.c (special_sections_c): Add ".ctf". (assign_file_positions_for_non_load_sections): Note that compressed debugging sections etc are not assigned here. Treat CTF sections like SEC_ELF_COMPRESS sections when is_linker_output: sh_offset -1. (assign_file_positions_except_relocs): Likewise. (find_section_in_list): Note that debugging and CTF sections, as well as reloc sections, are assigned later. (_bfd_elf_assign_file_positions_for_non_load): CTF sections get their size and contents updated. (_bfd_elf_set_section_contents): Skip CTF sections: unlike compressed sections, they have no uncompressed content to copy at this stage. * elflink.c (elf_link_swap_symbols_out): Call the examine_strtab callback right before the strtab is written out. (bfd_elf_final_link): Don't cache the section contents of CTF sections: they are not populated yet. Call the emit_ctf callback right at the end, after all the symbols and strings are flushed out. ld/ * ldlang.h: (struct lang_input_statement_struct): Add the_ctf. (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (ldlang_ctf_apply_strsym): Declare. (ldlang_write_ctf_late): Likewise. * ldemul.h (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. (ld_emulation_xfer_type) <emit_ctf_early>: Likewise. (ld_emulation_xfer_type) <examine_strtab_for_ctf>: Likewise. * ldemul.c (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. * ldlang.c: Include ctf-api.h. (CTF_COMPRESSION_THRESHOLD): New. (ctf_output): New. Initialized in... (ldlang_open_ctf): ... this new function. Open all the CTF sections in the input files: mark them non-loaded and empty so as not to copy their contents to the output, but linker-created so the section gets created in the target. (ldlang_merge_ctf): New, merge types via ctf_link_add_ctf and ctf_link. (ldlang_ctf_apply_strsym): New, an examine_strtab callback: wrap ldemul_examine_strtab_for_ctf. (lang_write_ctf): New, write out the CTF section. (ldlang_write_ctf_late): New, late call via bfd's emit_ctf hook. (lang_process): Call ldlang_open_ctf, ldlang_merge_ctf, and lang_write_ctf. * ldmain.c (link_callbacks): Add ldlang_ctf_apply_strsym, ldlang_write_ctf_late. * emultempl/aix.em: Add ctf-api.h. * emultempl/armcoff.em: Likewise. * emultempl/beos.em: Likewise. * emultempl/elf.em: Likewise. * emultempl/generic.em: Likewise. * emultempl/linux.em: Likewise. * emultempl/msp430.em: Likewise. * emultempl/pe.em: Likewise. * emultempl/pep.em: Likewise. * emultempl/ticoff.em: Likewise. * emultempl/vanilla.em: Likewise. * ldcref.c: Likewise. * ldctor.c: Likewise. * ldelf.c: Likewise. * ldelfgen.c: Likewise. * ldemul.c: Likewise. * ldexp.c: Likewise. * ldfile.c: Likewise. * ldgram.c: Likewise. * ldlex.l: Likewise. * ldmain.c: Likewise. * ldmisc.c: Likewise. * ldver.c: Likewise. * ldwrite.c: Likewise. * lexsup.c: Likewise. * mri.c: Likewise. * pe-dll.c: Likewise. * plugin.c: Likewise. * ldelfgen.c (ldelf_emit_ctf_early): New. (ldelf_examine_strtab_for_ctf): tell libctf about the symtab and strtab. (struct ctf_strsym_iter_cb_arg): New, state to do so. (ldelf_ctf_strtab_iter_cb): New: tell libctf about each string in the strtab in turn. (ldelf_ctf_symbols_iter_cb): New, tell libctf about each symbol in the symtab in turn. * ldelfgen.h (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (struct ctf_file): Likewise. (ldelf_emit_ctf_early): Declare. (ldelf_examine_strtab_for_ctf): Likewise. * emultempl/elf-generic.em (LDEMUL_EMIT_CTF_EARLY): Set it. (LDEMUL_EXAMINE_STRTAB_FOR_CTF): Likewise. * emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add emit_ctf_early and examine_strtab_for_ctf, NULL by default. * emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/linux.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/vanilla.em (ld_vanilla_emulation): Likewise. * Makefile.am: Pull in libctf (and zlib, a transitive requirement for compressed CTF section emission). Pass it on to DejaGNU. * configure.ac: Add AM_ZLIB. * aclocal.m4: Added zlib.m4. * Makefile.in: Regenerated. * testsuite/ld-bootstrap/bootstrap.exp: Use it when relinking ld.
2019-07-14 05:38:00 +08:00
struct elf_strtab_hash;
libctf, include, binutils, gdb, ld: rename ctf_file_t to ctf_dict_t The naming of the ctf_file_t type in libctf is a historical curiosity. Back in the Solaris days, CTF dictionaries were originally generated as a separate file and then (sometimes) merged into objects: hence the datatype was named ctf_file_t, and known as a "CTF file". Nowadays, raw CTF is essentially never written to a file on its own, and the datatype changed name to a "CTF dictionary" years ago. So the term "CTF file" refers to something that is never a file! This is at best confusing. The type has also historically been known as a 'CTF container", which is even more confusing now that we have CTF archives which are *also* a sort of container (they contain CTF dictionaries), but which are never referred to as containers in the source code. So fix this by completing the renaming, renaming ctf_file_t to ctf_dict_t throughout, and renaming those few functions that refer to CTF files by name (keeping compatibility aliases) to refer to dicts instead. Old users who still refer to ctf_file_t will see (harmless) pointer-compatibility warnings at compile time, but the ABI is unchanged (since C doesn't mangle names, and ctf_file_t was always an opaque type) and things will still compile fine as long as -Werror is not specified. All references to CTF containers and CTF files in the source code are fixed to refer to CTF dicts instead. Further (smaller) renamings of annoyingly-named functions to come, as part of the process of souping up queries across whole archives at once (needed for the function info and data object sections). binutils/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * objdump.c (dump_ctf_errs): Rename ctf_file_t to ctf_dict_t. (dump_ctf_archive_member): Likewise. (dump_ctf): Likewise. Use ctf_dict_close, not ctf_file_close. * readelf.c (dump_ctf_errs): Rename ctf_file_t to ctf_dict_t. (dump_ctf_archive_member): Likewise. (dump_section_as_ctf): Likewise. Use ctf_dict_close, not ctf_file_close. gdb/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ctfread.c: Change uses of ctf_file_t to ctf_dict_t. (ctf_fp_info::~ctf_fp_info): Call ctf_dict_close, not ctf_file_close. include/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h (ctf_file_t): Rename to... (ctf_dict_t): ... this. Keep ctf_file_t around for compatibility. (struct ctf_file): Likewise rename to... (struct ctf_dict): ... this. (ctf_file_close): Rename to... (ctf_dict_close): ... this, keeping compatibility function. (ctf_parent_file): Rename to... (ctf_parent_dict): ... this, keeping compatibility function. All callers adjusted. * ctf.h: Rename references to ctf_file_t to ctf_dict_t. (struct ctf_archive) <ctfa_nfiles>: Rename to... <ctfa_ndicts>: ... this. ld/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ldlang.c (ctf_output): This is a ctf_dict_t now. (lang_ctf_errs_warnings): Rename ctf_file_t to ctf_dict_t. (ldlang_open_ctf): Adjust comment. (lang_merge_ctf): Use ctf_dict_close, not ctf_file_close. * ldelfgen.h (ldelf_examine_strtab_for_ctf): Rename ctf_file_t to ctf_dict_t. Change opaque declaration accordingly. * ldelfgen.c (ldelf_examine_strtab_for_ctf): Adjust. * ldemul.h (examine_strtab_for_ctf): Likewise. (ldemul_examine_strtab_for_ctf): Likewise. * ldeuml.c (ldemul_examine_strtab_for_ctf): Likewise. libctf/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h: Rename ctf_file_t to ctf_dict_t: all declarations adjusted. (ctf_fileops): Rename to... (ctf_dictops): ... this. (ctf_dedup_t) <cd_id_to_file_t>: Rename to... <cd_id_to_dict_t>: ... this. (ctf_file_t): Fix outdated comment. <ctf_fileops>: Rename to... <ctf_dictops>: ... this. (struct ctf_archive_internal) <ctfi_file>: Rename to... <ctfi_dict>: ... this. * ctf-archive.c: Rename ctf_file_t to ctf_dict_t. Rename ctf_archive.ctfa_nfiles to ctfa_ndicts. Rename ctf_file_close to ctf_dict_close. All users adjusted. * ctf-create.c: Likewise. Refer to CTF dicts, not CTF containers. (ctf_bundle_t) <ctb_file>: Rename to... <ctb_dict): ... this. * ctf-decl.c: Rename ctf_file_t to ctf_dict_t. * ctf-dedup.c: Likewise. Rename ctf_file_close to ctf_dict_close. Refer to CTF dicts, not CTF containers. * ctf-dump.c: Likewise. * ctf-error.c: Likewise. * ctf-hash.c: Likewise. * ctf-inlines.h: Likewise. * ctf-labels.c: Likewise. * ctf-link.c: Likewise. * ctf-lookup.c: Likewise. * ctf-open-bfd.c: Likewise. * ctf-string.c: Likewise. * ctf-subr.c: Likewise. * ctf-types.c: Likewise. * ctf-util.c: Likewise. * ctf-open.c: Likewise. (ctf_file_close): Rename to... (ctf_dict_close): ...this. (ctf_file_close): New trivial wrapper around ctf_dict_close, for compatibility. (ctf_parent_file): Rename to... (ctf_parent_dict): ... this. (ctf_parent_file): New trivial wrapper around ctf_parent_dict, for compatibility. * libctf.ver: Add ctf_dict_close and ctf_parent_dict.
2020-11-20 21:34:04 +08:00
struct ctf_dict;
bfd, ld: add CTF section linking This is quite complicated because the CTF section's contents depend on the final contents of the symtab and strtab, because it has two sections whose contents are shuffled to be in 1:1 correspondence with the symtab, and an internal strtab that gets deduplicated against the ELF strtab (with offsets adjusted to point into the ELF strtab instead). It is also compressed if large enough, so its size depends on its contents! So we cannot construct it as early as most sections: we cannot even *begin* construction until after the symtab and strtab are finalized. Thankfully there is already one section treated similarly: compressed debugging sections: the only differences are that compressed debugging sections have extra handling to deal with their changing name if compressed (CTF sections are always called ".ctf" for now, though we have reserved ".ctf.*" against future use), and that compressed debugging sections have previously-uncompressed content which has to be stashed away for later compression, while CTF sections have no content at all until we generate it (very late). BFD also cannot do the link itself: libctf knows how to do it, and BFD cannot call libctf directly because libctf already depends on bfd for file I/O. So we have to use a pair of callbacks, one, examine_strtab, which allows a caller to examine the symtab and strtab after finalization (called from elf_link_swap_symbols_out(), right before the symtabs are written, and after the strtab has been finalized), and one which actually does the emission (called emit_ctf simply because it is grouped with a bunch of section-specific late-emission function calls at the bottom of bfd_elf_final_link, and a section-specific name seems best for that). emit_ctf is actually called *twice*: once from lang_process if the emulation suggests that this bfd target does not examine the symtab or strtab, and once via a bfd callback if it does. (This means that non-ELF targets still get CTF emitted, even though the late CTF emission stage is never called for them). v2: merged with non-ELF support patch: slight commit message adjustments. v3: do not spend time merging CTF, or crash, if the CTF section is explicitly discarded. Do not try to merge or compress CTF unless linking. v4: add CTF_COMPRESSION_THRESHOLD. Annul the freed input ctf_file_t's after writeout: set SEC_IN_MEMORY on the output contents so a future bfd enhancement knows it could free it. Add SEC_LINKER_CREATED | SEC_KEEP to avoid having to add .ctf to the linker script. Drop now-unnecessary ldlang.h-level elf-bfd.h include and hackery around it. Adapt to elf32.em->elf.em and elf-generic.em->ldelf*.c changes. v5: fix tabdamage. Drop #inclusions in .h files: include in .c files, .em files, and use struct forwards instead. Use bfd_section_is_ctf inline function rather than SECTION_IS_CTF macro. Move a few comments. * Makefile.def (dependencies): all-ld depends on all-libctf. * Makefile.in: Regenerated. include/ * bfdlink.h (elf_strtab_hash): New forward. (elf_sym_strtab): Likewise. (struct bfd_link_callbacks <examine_strtab>): New. (struct bfd_link_callbacks <emit_ctf>): Likewise. bfd/ * elf-bfd.h (bfd_section_is_ctf): New inline function. * elf.c (special_sections_c): Add ".ctf". (assign_file_positions_for_non_load_sections): Note that compressed debugging sections etc are not assigned here. Treat CTF sections like SEC_ELF_COMPRESS sections when is_linker_output: sh_offset -1. (assign_file_positions_except_relocs): Likewise. (find_section_in_list): Note that debugging and CTF sections, as well as reloc sections, are assigned later. (_bfd_elf_assign_file_positions_for_non_load): CTF sections get their size and contents updated. (_bfd_elf_set_section_contents): Skip CTF sections: unlike compressed sections, they have no uncompressed content to copy at this stage. * elflink.c (elf_link_swap_symbols_out): Call the examine_strtab callback right before the strtab is written out. (bfd_elf_final_link): Don't cache the section contents of CTF sections: they are not populated yet. Call the emit_ctf callback right at the end, after all the symbols and strings are flushed out. ld/ * ldlang.h: (struct lang_input_statement_struct): Add the_ctf. (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (ldlang_ctf_apply_strsym): Declare. (ldlang_write_ctf_late): Likewise. * ldemul.h (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. (ld_emulation_xfer_type) <emit_ctf_early>: Likewise. (ld_emulation_xfer_type) <examine_strtab_for_ctf>: Likewise. * ldemul.c (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. * ldlang.c: Include ctf-api.h. (CTF_COMPRESSION_THRESHOLD): New. (ctf_output): New. Initialized in... (ldlang_open_ctf): ... this new function. Open all the CTF sections in the input files: mark them non-loaded and empty so as not to copy their contents to the output, but linker-created so the section gets created in the target. (ldlang_merge_ctf): New, merge types via ctf_link_add_ctf and ctf_link. (ldlang_ctf_apply_strsym): New, an examine_strtab callback: wrap ldemul_examine_strtab_for_ctf. (lang_write_ctf): New, write out the CTF section. (ldlang_write_ctf_late): New, late call via bfd's emit_ctf hook. (lang_process): Call ldlang_open_ctf, ldlang_merge_ctf, and lang_write_ctf. * ldmain.c (link_callbacks): Add ldlang_ctf_apply_strsym, ldlang_write_ctf_late. * emultempl/aix.em: Add ctf-api.h. * emultempl/armcoff.em: Likewise. * emultempl/beos.em: Likewise. * emultempl/elf.em: Likewise. * emultempl/generic.em: Likewise. * emultempl/linux.em: Likewise. * emultempl/msp430.em: Likewise. * emultempl/pe.em: Likewise. * emultempl/pep.em: Likewise. * emultempl/ticoff.em: Likewise. * emultempl/vanilla.em: Likewise. * ldcref.c: Likewise. * ldctor.c: Likewise. * ldelf.c: Likewise. * ldelfgen.c: Likewise. * ldemul.c: Likewise. * ldexp.c: Likewise. * ldfile.c: Likewise. * ldgram.c: Likewise. * ldlex.l: Likewise. * ldmain.c: Likewise. * ldmisc.c: Likewise. * ldver.c: Likewise. * ldwrite.c: Likewise. * lexsup.c: Likewise. * mri.c: Likewise. * pe-dll.c: Likewise. * plugin.c: Likewise. * ldelfgen.c (ldelf_emit_ctf_early): New. (ldelf_examine_strtab_for_ctf): tell libctf about the symtab and strtab. (struct ctf_strsym_iter_cb_arg): New, state to do so. (ldelf_ctf_strtab_iter_cb): New: tell libctf about each string in the strtab in turn. (ldelf_ctf_symbols_iter_cb): New, tell libctf about each symbol in the symtab in turn. * ldelfgen.h (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (struct ctf_file): Likewise. (ldelf_emit_ctf_early): Declare. (ldelf_examine_strtab_for_ctf): Likewise. * emultempl/elf-generic.em (LDEMUL_EMIT_CTF_EARLY): Set it. (LDEMUL_EXAMINE_STRTAB_FOR_CTF): Likewise. * emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add emit_ctf_early and examine_strtab_for_ctf, NULL by default. * emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/linux.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/vanilla.em (ld_vanilla_emulation): Likewise. * Makefile.am: Pull in libctf (and zlib, a transitive requirement for compressed CTF section emission). Pass it on to DejaGNU. * configure.ac: Add AM_ZLIB. * aclocal.m4: Added zlib.m4. * Makefile.in: Regenerated. * testsuite/ld-bootstrap/bootstrap.exp: Use it when relinking ld.
2019-07-14 05:38:00 +08:00
Move elf32.em and elf-generic.em functions Many ELF linker targets support multiple "emulations" and thus have multiple copies of elf32.em being compiled and linked into ld. This patch moves much of elf32.em and elf-generic.em into files which will be compiled just once, resulting in a 20% decrease in ld size for --enable-targets=all. * Makefile.am (ALL_EMUL_EXTRA_OFILES): Add ldelf and ldelfgen. (CFILES, HFILES, EXTRA_ld_new_SOURCES): Likewise. * configure.tgt: Formatting. (targ_extra_ofiles): Init to ldelf.o ldelfgen.o, reset to just ldelfgen.o for generic ELF targets, and empty for non-ELF. * emultempl/aarch64elf.em (gldaarch64_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, aarch64_for_each_input_file_wrapper), (aarch64_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/alphaelf.em (alpha_after_parse): Use ldelf_map_segments. * emultempl/armelf.em (gldarm_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, arm_for_each_input_file_wrapper), (arm_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/cr16elf.em (cr16elf_after_parse): Use ldelf_map_segments. * emultempl/crxelf.em (crxelf_after_parse): Likewise. Delete declaration. * emultempl/cskyelf.em (gldcsky_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, csky_for_each_input_file_wrapper), (csky_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/genelf.em: Include ldelfgen.h. (gld${EMULATION_NAME}_before_allocation): Use ldelf_map_segments. * emultempl/hppaelf.em (hppaelf_after_parse): Likewise. (hppaelf_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, hppa_for_each_input_file_wrapper), (hppa_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ia64elf.em (ia64elf_after_parse): Use ldelf_map_segments. * emultempl/m68hc1xelf.em (real_func), (m68hc11_for_each_input_file_wrapper), (m68hc11_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/metagelf.em (metagelf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, metag_for_each_input_file_wrapper), (metag_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mipself.em (real_func), (mips_for_each_input_file_wrapper), (mips_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/mmo.em: Don't include elf-bfd.h, do include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/nds32elf.em (nds32_elf_after_parse): Use ldelf_after_parse. (nds32_elf_after_allocation): Comment fix. * emultempl/nios2elf.em (nios2elf_layout_sections_again): Use ldelf_map_segments. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, nios2_for_each_input_file_wrapper), (nios2_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. * emultempl/ppc32elf.em (gld${EMULATION_NAME}_load_symbols): Delete declaration. (ppc_recognized_file): Call ldelf_load_symbols. * emultempl/ppc64elf.em (ppc_layout_sections_again): Likewise. (gld${EMULATION_NAME}_after_allocation): Likewise. (real_func, ppc_for_each_input_file_wrapper), (ppc_lang_for_each_input_file): Delete. (lang_for_each_input_file): Don't define. (gld${EMULATION_NAME}_load_symbols): Don't declare. (ppc64_recognized_file): Call ldelf_load_symbols. * emultempl/riscvelf.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/spuelf.em (spu_place_special_section): Use ldelf_place_orphan. * emultempl/tic6xdsbt.em (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/vms.em: Include ldelfgen.h. (gld${EMULATION_NAME}_after_allocation): Use ldelf_map_segments. * emultempl/elf32.em: Remove unnecessary headers, include ldelf.h and ldelfgen.h. Move much of file content to.. * ldelf.c: ..here. New file. * ldelf.h: New file. * emultempl/elf-generic.em: Move gld${EMULATION_NAME}_map_segments.. * ldelfgen.c: ..to here. * ldelfgen.h: New file. * ldlang.c (lang_for_each_input_file): Adjust to only call func on real files. (lang_for_each_file): Likewise. * po/SRC-POTFILES.in: Regenerate. * Makefile.in: Regenerate.
2019-09-09 21:37:35 +08:00
extern void ldelf_map_segments (bfd_boolean);
bfd, ld: add CTF section linking This is quite complicated because the CTF section's contents depend on the final contents of the symtab and strtab, because it has two sections whose contents are shuffled to be in 1:1 correspondence with the symtab, and an internal strtab that gets deduplicated against the ELF strtab (with offsets adjusted to point into the ELF strtab instead). It is also compressed if large enough, so its size depends on its contents! So we cannot construct it as early as most sections: we cannot even *begin* construction until after the symtab and strtab are finalized. Thankfully there is already one section treated similarly: compressed debugging sections: the only differences are that compressed debugging sections have extra handling to deal with their changing name if compressed (CTF sections are always called ".ctf" for now, though we have reserved ".ctf.*" against future use), and that compressed debugging sections have previously-uncompressed content which has to be stashed away for later compression, while CTF sections have no content at all until we generate it (very late). BFD also cannot do the link itself: libctf knows how to do it, and BFD cannot call libctf directly because libctf already depends on bfd for file I/O. So we have to use a pair of callbacks, one, examine_strtab, which allows a caller to examine the symtab and strtab after finalization (called from elf_link_swap_symbols_out(), right before the symtabs are written, and after the strtab has been finalized), and one which actually does the emission (called emit_ctf simply because it is grouped with a bunch of section-specific late-emission function calls at the bottom of bfd_elf_final_link, and a section-specific name seems best for that). emit_ctf is actually called *twice*: once from lang_process if the emulation suggests that this bfd target does not examine the symtab or strtab, and once via a bfd callback if it does. (This means that non-ELF targets still get CTF emitted, even though the late CTF emission stage is never called for them). v2: merged with non-ELF support patch: slight commit message adjustments. v3: do not spend time merging CTF, or crash, if the CTF section is explicitly discarded. Do not try to merge or compress CTF unless linking. v4: add CTF_COMPRESSION_THRESHOLD. Annul the freed input ctf_file_t's after writeout: set SEC_IN_MEMORY on the output contents so a future bfd enhancement knows it could free it. Add SEC_LINKER_CREATED | SEC_KEEP to avoid having to add .ctf to the linker script. Drop now-unnecessary ldlang.h-level elf-bfd.h include and hackery around it. Adapt to elf32.em->elf.em and elf-generic.em->ldelf*.c changes. v5: fix tabdamage. Drop #inclusions in .h files: include in .c files, .em files, and use struct forwards instead. Use bfd_section_is_ctf inline function rather than SECTION_IS_CTF macro. Move a few comments. * Makefile.def (dependencies): all-ld depends on all-libctf. * Makefile.in: Regenerated. include/ * bfdlink.h (elf_strtab_hash): New forward. (elf_sym_strtab): Likewise. (struct bfd_link_callbacks <examine_strtab>): New. (struct bfd_link_callbacks <emit_ctf>): Likewise. bfd/ * elf-bfd.h (bfd_section_is_ctf): New inline function. * elf.c (special_sections_c): Add ".ctf". (assign_file_positions_for_non_load_sections): Note that compressed debugging sections etc are not assigned here. Treat CTF sections like SEC_ELF_COMPRESS sections when is_linker_output: sh_offset -1. (assign_file_positions_except_relocs): Likewise. (find_section_in_list): Note that debugging and CTF sections, as well as reloc sections, are assigned later. (_bfd_elf_assign_file_positions_for_non_load): CTF sections get their size and contents updated. (_bfd_elf_set_section_contents): Skip CTF sections: unlike compressed sections, they have no uncompressed content to copy at this stage. * elflink.c (elf_link_swap_symbols_out): Call the examine_strtab callback right before the strtab is written out. (bfd_elf_final_link): Don't cache the section contents of CTF sections: they are not populated yet. Call the emit_ctf callback right at the end, after all the symbols and strings are flushed out. ld/ * ldlang.h: (struct lang_input_statement_struct): Add the_ctf. (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (ldlang_ctf_apply_strsym): Declare. (ldlang_write_ctf_late): Likewise. * ldemul.h (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. (ld_emulation_xfer_type) <emit_ctf_early>: Likewise. (ld_emulation_xfer_type) <examine_strtab_for_ctf>: Likewise. * ldemul.c (ldemul_emit_ctf_early): New. (ldemul_examine_strtab_for_ctf): Likewise. * ldlang.c: Include ctf-api.h. (CTF_COMPRESSION_THRESHOLD): New. (ctf_output): New. Initialized in... (ldlang_open_ctf): ... this new function. Open all the CTF sections in the input files: mark them non-loaded and empty so as not to copy their contents to the output, but linker-created so the section gets created in the target. (ldlang_merge_ctf): New, merge types via ctf_link_add_ctf and ctf_link. (ldlang_ctf_apply_strsym): New, an examine_strtab callback: wrap ldemul_examine_strtab_for_ctf. (lang_write_ctf): New, write out the CTF section. (ldlang_write_ctf_late): New, late call via bfd's emit_ctf hook. (lang_process): Call ldlang_open_ctf, ldlang_merge_ctf, and lang_write_ctf. * ldmain.c (link_callbacks): Add ldlang_ctf_apply_strsym, ldlang_write_ctf_late. * emultempl/aix.em: Add ctf-api.h. * emultempl/armcoff.em: Likewise. * emultempl/beos.em: Likewise. * emultempl/elf.em: Likewise. * emultempl/generic.em: Likewise. * emultempl/linux.em: Likewise. * emultempl/msp430.em: Likewise. * emultempl/pe.em: Likewise. * emultempl/pep.em: Likewise. * emultempl/ticoff.em: Likewise. * emultempl/vanilla.em: Likewise. * ldcref.c: Likewise. * ldctor.c: Likewise. * ldelf.c: Likewise. * ldelfgen.c: Likewise. * ldemul.c: Likewise. * ldexp.c: Likewise. * ldfile.c: Likewise. * ldgram.c: Likewise. * ldlex.l: Likewise. * ldmain.c: Likewise. * ldmisc.c: Likewise. * ldver.c: Likewise. * ldwrite.c: Likewise. * lexsup.c: Likewise. * mri.c: Likewise. * pe-dll.c: Likewise. * plugin.c: Likewise. * ldelfgen.c (ldelf_emit_ctf_early): New. (ldelf_examine_strtab_for_ctf): tell libctf about the symtab and strtab. (struct ctf_strsym_iter_cb_arg): New, state to do so. (ldelf_ctf_strtab_iter_cb): New: tell libctf about each string in the strtab in turn. (ldelf_ctf_symbols_iter_cb): New, tell libctf about each symbol in the symtab in turn. * ldelfgen.h (struct elf_sym_strtab): Add forward. (struct elf_strtab_hash): Likewise. (struct ctf_file): Likewise. (ldelf_emit_ctf_early): Declare. (ldelf_examine_strtab_for_ctf): Likewise. * emultempl/elf-generic.em (LDEMUL_EMIT_CTF_EARLY): Set it. (LDEMUL_EXAMINE_STRTAB_FOR_CTF): Likewise. * emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add emit_ctf_early and examine_strtab_for_ctf, NULL by default. * emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/linux.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise. * emultempl/vanilla.em (ld_vanilla_emulation): Likewise. * Makefile.am: Pull in libctf (and zlib, a transitive requirement for compressed CTF section emission). Pass it on to DejaGNU. * configure.ac: Add AM_ZLIB. * aclocal.m4: Added zlib.m4. * Makefile.in: Regenerated. * testsuite/ld-bootstrap/bootstrap.exp: Use it when relinking ld.
2019-07-14 05:38:00 +08:00
extern int ldelf_emit_ctf_early (void);
bfd, include, ld, binutils, libctf: CTF should use the dynstr/sym This is embarrassing. The whole point of CTF is that it remains intact even after a binary is stripped, providing a compact mapping from symbols to types for everything in the externally-visible interface of an ELF object: it has connections to the symbol table for that purpose, and to the string table to avoid duplicating symbol names. So it's a shame that the hooks I implemented last year served to hook it up to the .symtab and .strtab, which obviously disappear on strip, leaving any accompanying the CTF dict containing references to strings (and, soon, symbols) which don't exist any more because their containing strtab has been vaporized. The original Solaris design used .dynsym and .dynstr (well, actually, .ldynsym, which has more symbols) which do not disappear. So should we. Thankfully the work we did before serves as guide rails, and adjusting things to use the .dynstr and .dynsym was fast and easy. The only annoyance is that the dynsym is assembled inside elflink.c in a fairly piecemeal fashion, so that the easiest way to get the symbols out was to hook in before every call to swap_symbol_out (we also leave in a hook in front of symbol additions to the .symtab because it seems plausible that we might want to hook them in future too: for now that hook is unused). We adjust things so that rather than being offered a whole hash table of symbols at once, libctf is now given symbols one at a time, with st_name indexes already resolved and pointing at their final .dynstr offsets: it's now up to libctf to resolve these to names as needed using the strtab info we pass it separately. Some bits might be contentious. The ctf_new_dynstr callback takes an elf_internal_sym, and this remains an elf_internal_sym right down through the generic emulation layers into ldelfgen. This is no worse than the elf_sym_strtab we used to pass down, but in the future when we gain non-ELF CTF symtab support we might want to lower the elf_internal_sym to some other representation (perhaps a ctf_link_symbol) in bfd or in ldlang_ctf_new_dynsym. We rename the 'apply_strsym' hooks to 'acquire_strings' instead, becuse they no longer have anything to do with symbols. There are some API changes to pieces of API which are technically public but actually totally unused by anything and/or unused by anything but ld so they can change freely: the ctf_link_symbol gains new fields to allow symbol names to be given as strtab offsets as well as strings, and a symidx so that the symbol index can be passed in. ctf_link_shuffle_syms loses its callback parameter: the idea now is that linkers call the new ctf_link_add_linker_symbol for every symbol in .dynsym, feed in all the strtab entries with ctf_link_add_strtab, and then a call to ctf_link_shuffle_syms will apply both and arrange to use them to reorder the CTF symtab at CTF serialization time (which is coming in the next commit). Inside libctf we have a new preamble flag CTF_F_DYNSTR which is always set in v3-format CTF dicts from this commit forwards: CTF dicts without this flag are associated with .strtab like they used to be, so that old dicts' external strings don't turn to garbage when loaded by new libctf. Dicts with this flag are associated with .dynstr and .dynsym instead. (The flag is not the next in sequence because this commit was written quite late: the missing flags will be filled in by the next commit.) Tests forthcoming in a later commit in this series. bfd/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * elflink.c (elf_finalize_dynstr): Call examine_strtab after dynstr finalization. (elf_link_swap_symbols_out): Don't call it here. Call ctf_new_symbol before swap_symbol_out. (elf_link_output_extsym): Call ctf_new_dynsym before swap_symbol_out. (bfd_elf_final_link): Likewise. * elf.c (swap_out_syms): Pass in bfd_link_info. Call ctf_new_symbol before swap_symbol_out. (_bfd_elf_compute_section_file_positions): Adjust. binutils/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * readelf.c (dump_section_as_ctf): Use .dynsym and .dynstr, not .symtab and .strtab. include/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * bfdlink.h (struct elf_sym_strtab): Replace with... (struct elf_internal_sym): ... this. (struct bfd_link_callbacks) <examine_strtab>: Take only a symstrtab argument. <ctf_new_symbol>: New. <ctf_new_dynsym>: Likewise. * ctf-api.h (struct ctf_link_sym) <st_symidx>: New. <st_nameidx>: Likewise. <st_nameidx_set>: Likewise. (ctf_link_iter_symbol_f): Removed. (ctf_link_shuffle_syms): Remove most parameters, just takes a ctf_dict_t now. (ctf_link_add_linker_symbol): New, split from ctf_link_shuffle_syms. * ctf.h (CTF_F_DYNSTR): New. (CTF_F_MAX): Adjust. ld/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ldelfgen.c (struct ctf_strsym_iter_cb_arg): Rename to... (struct ctf_strtab_iter_cb_arg): ... this, changing fields: <syms>: Remove. <symcount>: Remove. <symstrtab>: Rename to... <strtab>: ... this. (ldelf_ctf_strtab_iter_cb): Adjust. (ldelf_ctf_symbols_iter_cb): Remove. (ldelf_new_dynsym_for_ctf): New, tell libctf about a single symbol. (ldelf_examine_strtab_for_ctf): Rename to... (ldelf_acquire_strings_for_ctf): ... this, only doing the strtab portion and not symbols. * ldelfgen.h: Adjust declarations accordingly. * ldemul.c (ldemul_examine_strtab_for_ctf): Rename to... (ldemul_acquire_strings_for_ctf): ... this. (ldemul_new_dynsym_for_ctf): New. * ldemul.h: Adjust declarations accordingly. * ldlang.c (ldlang_ctf_apply_strsym): Rename to... (ldlang_ctf_acquire_strings): ... this. (ldlang_ctf_new_dynsym): New. (lang_write_ctf): Call ldemul_new_dynsym_for_ctf with NULL to do the actual symbol shuffle. * ldlang.h (struct elf_strtab_hash): Adjust accordingly. * ldmain.c (bfd_link_callbacks): Wire up new/renamed callbacks. libctf/ChangeLog 2020-11-20 Nick Alcock <nick.alcock@oracle.com> * ctf-link.c (ctf_link_shuffle_syms): Adjust. (ctf_link_add_linker_symbol): New, unimplemented stub. * libctf.ver: Add it. * ctf-create.c (ctf_serialize): Set CTF_F_DYNSTR on newly-serialized dicts. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Check for the flag: open the symtab/strtab if not present, dynsym/dynstr otherwise. * ctf-archive.c (ctf_arc_bufpreamble): New, get the preamble from some arbitrary member of a CTF archive. * ctf-impl.h (ctf_arc_bufpreamble): Declare it.
2020-11-20 21:34:04 +08:00
extern void ldelf_acquire_strings_for_ctf
(struct ctf_dict *ctf_output, struct elf_strtab_hash *strtab);
extern void ldelf_new_dynsym_for_ctf
(struct ctf_dict *ctf_output, int symidx, struct elf_internal_sym *sym);
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