Gold resolves GOT-relative relocs relative to the GOT base +
0x8000 when the GOT is larger than 0x8000. However, previously
the _GLOBAL_OFFSET_TABLE_ symbol was set to GOT base + 0x8000
when the .got.plt was larger than 0x8000. This patch makes both
checks use the size of the .got section so that they agree when
to add 0x8000.
During --icf processing, gold was incorrectly processing the relocation
addend for references to items in a merge section. PC-relative references
and other forms of reference with a biased base address require a
non-section local symbol, where the addend is purely the bias.
gold/
PR gold/20642
PR gold/22820
* gc.h (gc_process_relocs): Flag STT_SECTION symbols in symvec.
* icf.cc (get_section_contents): For merge sections, ignore the
addend for relocations against non-section symbols.
gold/
PR gold/16504
* dynobj.cc (Versions::symbol_section_contents): Don't set
VERSYM_HIDDEN flag for undefined symbols.
* symtab.cc (Symbol_table::add_from_object): Don't override default
version definition with a different default version.
* symtab.h (Symbol::from_dyn): New method.
* testsuite/plugin_test.c (struct sym_info): Add ver field.
(claim_file_hook): Pass symbol version to plugin API.
(parse_readelf_line): Parse symbol version.
* testsuite/Makefile.am (ver_test_pr16504): New test case.
* testsuite/Makefile.in: Regenerate.
* testsuite/ver_test_pr16504.sh: New test script.
* testsuite/ver_test_pr16504_a.c: New source file.
* testsuite/ver_test_pr16504_a.script: New version script.
* testsuite/ver_test_pr16504_b.c: New source file.
* testsuite/ver_test_pr16504_b.script: New version script.
When checking a R_ARM_TARGET[12] relocation, we need a valid target
pointer, but the garbage collection code was passing a NULL instead.
The previous fix for this bug fixed the call to
scan.global_reloc_may_be_function_pointer, but missed the similar
call to scan.local_reloc_may_be_function_pointer.
gold/
PR gold/23046
* gc.h (gc_process_relocs): Pass target to
scan.local_reloc_may_be_function_pointer.
When checking a R_ARM_TARGET[12] relocation, we need a valid target
pointer, but the garbage collection code was passing a NULL instead.
gold/
PR gold/23046
* gc.h (gc_process_relocs): Pass target to
scan.global_reloc_may_be_function_pointer.
The gold change is to pick up HJ's PR22318 AC_PLUGINS update. The
ld change is to correct a file I generated from a modified tree.
gold/
* configure: Regenerate.
ld/
* po/BLD-POTFILES.in: Regenerate.
In addition to the existing relocs we need two more to mark all
instructions in the call sequence, PLTCALL on the call itself (plus
the toc restore insn for ppc64), and PLTSEQ on others. All
relocations in a particular sequence have the same symbol.
Example ppc64 ELFv2 assembly:
.reloc .,R_PPC64_PLTSEQ,puts
std 2,24(1)
addis 12,2,puts@plt@ha # .reloc .,R_PPC64_PLT16_HA,puts
ld 12,puts@plt@l(12) # .reloc .,R_PPC64_PLT16_LO_DS,puts
.reloc .,R_PPC64_PLTSEQ,puts
mtctr 12
.reloc .,R_PPC64_PLTCALL,puts
bctrl
ld 2,24(1)
Example ppc32 -fPIC assembly:
addis 12,30,puts+32768@plt@ha # .reloc .,R_PPC_PLT16_HA,puts+0x8000
lwz 12,12,puts+32768@plt@l # .reloc .,R_PPC_PLT16_LO,puts+0x8000
.reloc .,R_PPC_PLTSEQ,puts+32768
mtctr 12
.reloc .,R_PPC_PLTCALL,puts+32768
bctrl
Marking sequences like this allows the linker to convert them to nops
and a direct call if the target symbol turns out to be local.
When the call is __tls_get_addr, each relocation shown above is paired
with an R_PPC*_TLSLD or R_PPC*_TLSGD reloc to additionally mark the
sequence for possible TLS optimization. The TLSLD or TLSGD relocs are
emitted first.
include/
* elf/ppc.h (R_PPC_PLTSEQ, R_PPC_PLTCALL): Define.
* elf/ppc64.h (R_PPC64_PLTSEQ, R_PPC64_PLTCALL): Define.
bfd/
* elf32-ppc.c (ppc_elf_howto_raw): Add PLTSEQ and PLTCALL howtos.
(is_plt_seq_reloc): New function.
(ppc_elf_check_relocs): Handle PLTSEQ and PLTCALL relocs.
(ppc_elf_tls_optimize): Handle inline plt call sequence.
(ppc_elf_relax_section): Handle PLTCALL reloc.
(ppc_elf_relocate_section): Nop out inline plt call sequence when
resolving locally.
* elf64-ppc.c (ppc64_elf_howto_raw): Add R_PPC64_PLTSEQ and
R_PPC64_PLTCALL entries. Comment R_PPC64_TOCSAVE.
(has_tls_get_addr_call): Correct comment.
(is_branch_reloc): Add PLTCALL.
(is_plt_seq_reloc): New function.
(ppc64_elf_check_relocs): Handle PLT16_LO_DS reloc. Set
has_tls_reloc for R_PPC64_TLSGD and R_PPC64_TLSLD. Create plt
entry for R_PPC64_PLTCALL.
(ppc64_elf_tls_optimize): Handle inline plt call sequence.
(ppc_type_of_stub): Handle PLTCALL reloc.
(toc_adjusting_stub_needed): Likewise.
(ppc64_elf_relocate_section): Set "can_plt_call" for PLTCALL
reloc insn. Nop out inline plt call sequence when resolving
locally. Handle __tls_get_addr inline plt call optimization.
elfcpp/
* powerpc.h (R_POWERPC_PLTSEQ, R_POWERPC_PLTCALL): Define.
gold/
* powerpc.cc (Target_powerpc::Track_tls::maybe_skip_tls_get_addr_call):
Handle inline plt sequence relocs.
(Stub_table::Plt_stub_key::Plt_stub_key): Likewise.
(Target_powerpc::Scan::reloc_needs_plt_for_ifunc): Likewise.
(Target_powerpc::Relocate::relocate): Likewise.
Necessary if gcc is to use PLT16 relocs to implement -mlongcall, and
there isn't a good technical reason why local symbols should be
excluded from PLT16 support. Non-ifunc local symbol PLT entries go in
a separate section to other PLT entries. In a fixed position
executable they won't need to be relocated, and in a PIE or shared
library I chose to not implement lazy relocation.
bfd/
* elf64-ppc.c (LOCAL_PLT_ENTRY_SIZE): Define.
(struct ppc_stub_hash_entry): Add symtype field.
(PLT_KEEP): Define.
(struct ppc_link_hash_table): Add pltlocal and relpltlocal.
(create_linkage_sections): Create pltlocal and relpltlocal.
(ppc64_elf_check_relocs): Allow PLT relocs on local symbols.
Set PLT_KEEP.
(ppc64_elf_adjust_dynamic_symbol): Keep PLT entries for inline calls.
(allocate_dynrelocs): Allocate pltlocal and relpltlocal.
(ppc64_elf_size_dynamic_sections): Size pltlocal and relpltlocal.
Keep PLT entries for inline calls against locals.
(ppc_build_one_stub): Use pltlocal as appropriate.
(ppc_size_one_stub): Likewise.
(ppc64_elf_size_stubs): Set symtype.
(build_global_entry_stubs_and_plt): Init pltlocal and write
relpltlocal for globals.
(write_plt_relocs_for_local_syms): Likewise for local syms.
(ppc64_elf_relocate_section): Support PLT for local syms.
* elf32-ppc.c (PLT_KEEP): Define.
(struct ppc_elf_link_hash_table): Add pltlocal and relpltlocal.
(ppc_elf_create_glink): Create pltlocal and relpltlocal.
(ppc_elf_check_relocs): Allow PLT relocs on local symbols.
Set PLT_KEEP. Adjust update_local_sym_info call.
(ppc_elf_adjust_dynamic_symbol): Keep PLT entries for inline calls.
(allocate_dynrelocs): Allocate pltlocal and relpltlocal.
(ppc_elf_size_dynamic_sections): Size pltlocal and relpltlocal.
(ppc_elf_relocate_section): Support PLT16 relocs for local syms.
(write_global_sym_plt): Init pltlocal and write relpltlocal.
(ppc_finish_symbols): Likewise for locals.
ld/
* emulparams/elf32ppc.sh (OTHER_RELRO_SECTIONS_2): Add .branch_lt.
(OTHER_GOT_RELOC_SECTIONS): Add .rela.branch_lt.
* testsuite/ld-powerpc/elfv2so.d: Update for symbol/stub reordering.
* testsuite/ld-powerpc/relbrlt.d: Likewise.
* testsuite/ld-powerpc/relbrlt.s: Likewise.
* testsuite/ld-powerpc/tlsso.r: Likewise.
* testsuite/ld-powerpc/tlstocso.r: Likewise.
gold/
* powerpc.cc (Target_powerpc::lplt_): New variable.
(Target_powerpc::lplt_section): Associated accessor.
(Target_powerpc::plt_off): Handle local non-ifunc symbols.
(Target_powerpc::make_lplt_section): New function.
(Target_powerpc::make_local_plt_entry): New function.
(Powerpc_relobj::do_relocate_sections): Write out lplt.
(Output_data_plt_powerpc::first_plt_entry_offset): Zero for lplt.
(Output_data_plt_powerpc::add_local_entry): New function.
(Output_data_plt_powerpc::do_write): Ignore lplt.
(Target_powerpc::make_iplt_section): Make lplt first.
(Target_powerpc::make_brlt_section): Make .branch_lt relro.
(Target_powerpc::Scan::local): Handle PLT16 relocs.
The PowerPC64 ELFv2 ABI and the PowerPC SysV ABI support a number of
relocations that can be used to create and access a PLT entry.
However, the relocs are not well defined. The PLT16 family of relocs
talk about "the section offset or address of the procedure linkage
table entry". It's plain that we do need a relative address when PIC
as otherwise we'd have dynamic text relocations, but "section offset"
doesn't specify which section. The most obvious one, ".plt", isn't
that useful because there is no readily available way of addressing
the start of the ".plt" section. Much more useful would be "the
GOT/TOC-pointer relative offset of the procedure linkage table entry",
and I suppose you could argue that is a "section offset" of sorts.
For PowerPC64 it is better to use the same TOC-pointer relative
addressing even when non-PIC, since ".plt" may be located outside the
range of a 32-bit address. However, for ppc32 we do want an absolute
address when non-PIC as a GOT pointer may not be set up. Also, for
ppc32 PIC we have a similar situation to R_PPC_PLTREL24 in that the
GOT pointer is set to a location in the .got2 section and we need to
specify the .got2 offset in the PLT16 reloc addend.
This patch supports PLT16 relocations using these semantics. This is
not an ABI change for ppc32 since the relocations were not previously
supported by GNU ld, but is for ppc64 where some of the PLT16 relocs
were supported. I'm not particularly concerned since the old ppc64
PLT16 reloc semantics made them almost completely useless.
bfd/
* elf32-ppc.c (ppc_elf_check_relocs): Handle PLT16 relocs.
(ppc_elf_relocate_section): Likewise.
* elf64-ppc.c (ppc64_elf_check_relocs): Handle PLT16_LO_DS.
(ppc64_elf_relocate_section): Likewise. Correct PLT16
resolution to plt entry relative to toc pointer.
gold/
* powerpc.cc (Target_powerpc::plt_off): New functions.
(is_plt16_reloc): New function.
(Stub_table::plt_off): Use Target_powerpc::plt_off.
(Stub_table::plt_call_size): Use plt_off.
(Stub_table::do_write): Likewise.
(Target_powerpc::Scan::get_reference_flags): Return RELATIVE_REF
for PLT16 relocations.
(Target_powerpc::Scan::reloc_needs_plt_for_ifunc): Return true
for PLT16 relocations.
(Target_powerpc::Scan::global): Make a PLT entry for PLT16 relocations.
(Target_powerpc::Relocate::relocate): Support PLT16 relocations.
(Powerpc_scan_relocatable_reloc::global_strategy): Return RELOC_SPECIAL
for ppc32 plt16 relocs.
Relocations referring to discarded sections are now treated as errors
instead of warnings.
Also with this patch, we will now print the section group signature and the
object file with the prevailing definition of that group along with the
name of the symbol that the relocation is referring to. This additional
information should be much more useful to anyone trying to track down
the source of such errors.
To do so, we now map each discarded section to the Kept_section info in
the Layout class, and defer the logic that maps a discarded section to
its counterpart in the kept group. This gives us the information we need
to identify the signature symbol given the discarded section, and the
name of the object file that provided the prevailing (i.e., first)
definition of that group.
gold/
* object.cc (Sized_relobj_file::include_section_group): Store
reference to Kept_section info for discarded comdat sections
regardless of size. Move size checking to map_to_kept_section.
(Sized_relobj_file::include_linkonce_section): Likewise.
(Sized_relobj_file::map_to_kept_section): Add section name parameter.
Insert size checking logic from above functions.
(Sized_relobj_file::find_kept_section_object): New method.
(Sized_relobj_file::get_symbol_name): New method.
* object.h (Sized_relobj_file::map_to_kept_section): Add section_name
parameter. Adjust all callers.
(Sized_relobj_file::find_kept_section_object): New method.
(Sized_relobj_file::get_symbol_name): New method.
(Sized_relobj_file::Kept_comdat_section): Replace object and shndx
fields with sh_size, kept_section, symndx, and is_comdat fields.
(Sized_relobj_file::set_kept_comdat_section): Replace kept_object
and kept_shndx parameters with is_comdat, symndx, sh_size, and
kept_section.
(Sized_relobj_file::get_kept_comdat_section): Likewise.
* target-reloc.h (enum Comdat_behavior): Change CB_WARNING to CB_ERROR.
Adjust all references.
(issue_undefined_symbol_error): New function template.
(relocate_section): Pass section name to map_to_kept_section.
Move discarded section code to new function above.
* aarch64.cc (Target_aarch64::scan_reloc_section_for_stubs): Move
declaration for gsym out one level. Call issue_discarded_error.
* arm.cc (Target_arm::scan_reloc_section_for_stubs): Likewise.
* powerpc.cc (Relocate_comdat_behavior): Change CB_WARNING to CB_ERROR.
The record_got_page_entry function records and updates the maximum
number of GOT page entries which may be required by an object. In the
case where an existing GOT page entry was expanded, only the entry
belonging to output GOT would have its page count updated. This leaves
the entry belonging to the object GOT with the num_pages count of 1 it
was originally initialized with. Later on when GOTs are being merged in a
multi-got link, this causes the value of entry->num_pages in
add_got_page_entries to always be 1 and underestimates the number of pages
required for the new entry. This in turn leads to an assertion failure in
get_got_page_offset where we run out of pages.
Fix by obtaining the object's GOT entry unconditionally and not just
the first time it gets created. Now that entry2 is always valid, remove
the useless NULL checks.
gold/
PR gold/22770
* mips.cc (Mips_got_info::record_got_page_entry): Fetch existing
page entries for the object's GOT.
During a -r (or --emit-relocs) link, if two sections had the same name but
different section types, gold would put relocations for both sections into
the same relocation section even though the data sections remained separate.
For .eh_frame sections, when one section is PROGBITS and another is
X86_64_UNWIND, we really should be using the UNWIND section type and
combining the sections anyway. For other sections, we should be
creating one relocation section for each output data section.
gold/
PR gold/23016
* incremental.cc (can_incremental_update): Check for unwind section
type.
* layout.h (Layout::layout): Add sh_type parameter.
* layout.cc (Layout::layout): Likewise.
(Layout::layout_reloc): Create new output reloc section if data
section does not already have one.
(Layout::layout_eh_frame): Check for unwind section type.
(Layout::make_eh_frame_section): Use unwind section type for .eh_frame
and .eh_frame_hdr.
* object.h (Sized_relobj_file::Shdr_write): New typedef.
(Sized_relobj_file::layout_section): Add sh_type parameter.
(Sized_relobj_file::Deferred_layout::Deferred_layout): Add sh_type
parameter.
* object.cc (Sized_relobj_file::check_eh_frame_flags): Check for
unwind section type.
(Sized_relobj_file::layout_section): Add sh_type parameter; pass it
to Layout::layout.
(Sized_relobj_file::do_layout): Make local copy of sh_type.
Force .eh_frame sections to unwind section type.
Pass sh_type to layout_section.
(Sized_relobj_file<size, big_endian>::do_layout_deferred_sections):
Pass sh_type to layout_section.
* output.cc (Output_section::Output_section): Initialize reloc_section_.
* output.h (Output_section::reloc_section): New method.
(Output_section::set_reloc_section): New method.
(Output_section::reloc_section_): New data member.
* target.h (Target::unwind_section_type): New method.
(Target::Target_info::unwind_section_type): New data member.
* aarch64.cc (aarch64_info): Add unwind_section_type.
* arm.cc (arm_info, arm_nacl_info): Likewise.
* i386.cc (i386_info, i386_nacl_info, iamcu_info): Likewise.
* mips.cc (mips_info, mips_nacl_info): Likewise.
* powerpc.cc (powerpc_info): Likewise.
* s390.cc (s390_info): Likewise.
* sparc.cc (sparc_info): Likewise.
* tilegx.cc (tilegx_info): Likewise.
* x86_64.cc (x86_64_info, x86_64_nacl_info): Likewise.
* testsuite/Makefile.am (pr23016_1, pr23016_2): New test cases.
* testsuite/Makefile.in: Regenerate.
* testsuite/testfile.cc: Add unwind_section_type.
* testsuite/pr23016_1.sh: New test script.
* testsuite/pr23016_1a.s: New source file.
* testsuite/pr23016_1b.s: New source file.
* testsuite/pr23016_2.sh: New test script.
* testsuite/pr23016_2a.s: New source file.
* testsuite/pr23016_2b.s: New source file.
In PR 22868, two IR files provide conflicting visibility for a symbol.
When a def with PROTECTED visibility is seen after a def with DEFAULT
visibility, gold does not override the visibility. Later, if the
replacement object define the symbol with DEFAULT visibility, the symbol
remains DEFAULT. This was caused by a recent change to allow multiply-defined
absolute symbols, combined with the fact that the plugin framework was using
SHN_ABS as the section index for placeholder symbols. The solution is to
use a real (but arbitrary) section index.
gold/
PR gold/22868
* plugin.cc (Sized_pluginobj::do_add_symbols): Use a real section
index instead of SHN_ABS for defined symbols.
* testsuite/Makefile.am (plugin_pr22868): New test case.
* testsuite/Makefile.in: Regenerate
* testsuite/plugin_pr22868.sh: New test script.
* testsuite/plugin_pr22868_a.c: New source file.
* testsuite/plugin_pr22868_b.c: New source file.
This option does not merge certain text sections with prefixes
.text.hot, .text.unlikely, .text.startup and .text.exit.
* layout.cc (Layout::default_section_order): Check for text section
prefixes.
(Layout::text_section_name_mapping): New static member.
(Layout::text_section_name_mapping_count): New static member.
(Layout::match_section_name): New static function.
(Layout::output_section_name): Check for text section prefixes.
* layout.h (Output_section_order::ORDER_TEXT_HOT): New enum value.
(Output_section_order::ORDER_TEXT_STARTUP): New enum value.
(Output_section_order::ORDER_TEXT_EXIT): New enum value.
(Output_section_order::ORDER_TEXT_UNLIKELY): New enum value.
(Layout::text_section_name_mapping): New static member.
(Layout::text_section_name_mapping_count): New static member.
(Layout::match_section_name): New static function.
* options.h (keep_text_section_prefix): New -z option.
* testsuite/Makefile.am (keep_text_section_prefix): New test.
* testsuite/Makefile.in: Regenerate.
* testsuite/keep_text_section_prefix.cc: New test source.
* testsuite/keep_text_section_prefix.sh: New test script.
2018-02-07 Sriraman Tallam <tmsriram@google.com>
* expression.cc (Symbol_expression::set_expr_sym_in_real_elf):
New method.
(Unary_expression::set_expr_sym_in_real_elf): New method.
(Binary_expression::set_expr_sym_in_real_elf): New method.
(Trinary_expression::set_expr_sym_in_real_elf): New method.
* plugin.cc (get_symbol_resolution_info): Fix symbol resolution if
defined or used in defsyms.
* plugin.h (Plugin_manager::is_defsym_def): New method.
(Plugin_manager::Plugin_manager): Initialize defsym_defines_set_.
(Plugin_manager::defsym_defines_set_): New member.
(Plugin_manager::Defsym_defines_set): New typedef.
* script.cc (Script_options::set_defsym_uses_in_real_elf): New method.
(Script_options::find_defsym_defs): New method.
* script.h (Expression::set_expr_sym_in_real_elf): New method.
(Symbol_assignment::is_defsym): New method.
(Symbol_assignment::value): New method.
(Script_options::find_defsym_defs): New method.
(Script_options::set_defsym_uses_in_real_elf): New method.
* testsuite/Makefile.am (plugin_test_defsym): New test.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c: Check for new symbol resolution.
* testsuite/plugin_test_defsym.sh: New script.
* testsuite/plugin_test_defsym.c: New test source.
This reverts most of commit 1be5d8d3bb.
Left in place are addition of --no-plt-align to some ppc32 ld tests
and the ld.texinfo --no-plt-thread-safe fix.
Reads the maximum_operations_per_instruction field, added in DWARF-4 to the
line number program header.
gold/
* PR gold/22776
* dwarf_reader.cc (Sized_dwarf_line_info::read_header_prolog): Add
support for DWARF-4 line number tables.
* dwarf_reader.h (Sized_dwarf_line_info::max_ops_per_insn): New field.
Asking for ppc32 plt call stubs to be aligned at 32 byte boundaries
didn't quite work. For ld.bfd they were spaced 32 bytes apart, but
only started on a 16 byte boundary. ld.gold also didn't get it right.
Finding that bug made me check over the ppc64 plt stub alignment,
where I found that negative values for alignment (meaning align to
minimize boundary crossing) were not accepted. Since no one has
complained about that, I guess I could have removed the feature from
ld.bfd documentation, but I've opted instead to correct the code.
I've also added an optional alignment paramenter for ppc32
--plt-align, for some consistency with gold and ppc64 ld.bfd.
bfd/
* elf32-ppc.c (ppc_elf_create_glink): Correct alignment of .glink.
* elf64-ppc.c (ppc64_elf_size_stubs): Handle negative plt_stub_align.
(ppc64_elf_build_stubs): Likewise.
gold/
* powerpc.cc (param_plt_align): New function supplying default
--plt-align values. Use it..
(Stub_table::plt_call_align): ..here, and..
(Output_data_glink::global_entry_align): ..here.
(Stub_table::stub_align): Correct 32-bit minimum alignment.
ld/
* emultempl/ppc32elf.em: Support optional --plt-align arg.
* emultempl/ppc64elf.em: Support negative --plt-align arg.
This is in preparation for the next patch adding Spectre variant 2
mitigation for PowerPC and PowerPC64. Besides tidying code involved
in stub output (to reduce the number of places where bctr is output),
the patch adds some user visible features:
1) PowerPC64 ELFv2 global entry stubs now are aligned under the
control of --plt-align, with a default alignment of 32 bytes.
2) PowerPC64 __glink_PLTresolve is no longer padded out with nops.
3) PowerPC32 PLT stubs are aligned under the control of --plt-align,
with the default alignment being 16 bytes as before.
4) The PowerPC32 branch/nop table emitted before __glink_PLTresolve
is now smaller in many cases. It was sized incorrectly when the
__tls_get_addr_opt stub was used, and unnecessarily included space
for local ifuncs.
bfd/
* elf32-ppc.c (GLINK_ENTRY_SIZE): Add parameters, handle
__tls_get_addr_opt, and alignment sizing.
(TLS_GET_ADDR_GLINK_SIZE): Delete.
(is_nonpic_glink_stub): Don't use GLINK_ENTRY_SIZE.
(ppc_elf_get_synthetic_symtab): Recognize stubs spaced at 4, 6,
or 8 insns.
(ppc_elf_link_hash_table_create): Init new ppc_elf_params field.
(allocate_dynrelocs): Use new GLINK_ENTRY_SIZE.
(ppc_elf_size_dynamic_sections): Likewise. Size branch table
by PLT reloc count.
(write_glink_stub): Handle __tls_get_addr_opt stub.
Pad out to size given by GLINK_ENTRY_SIZE.
(ppc_elf_relocate_section): Adjust write_glink_stub call.
(ppc_elf_finish_dynamic_symbol): Likewise.
(ppc_elf_finish_dynamic_sections): Write PLTresolve without using
insn array since so many need rewriting.
* elf32-ppc.h (struct ppc_elf_params): Add plt_stub_align.
* elf64-ppc.c (GLINK_PLTRESOLVE_SIZE): Rename from
GLINK_CALL_STUB_SIZE. Add htab param and evaluate to size without
nops. Adjust all uses.
(ppc64_elf_get_synthetic_symtab): Don't use GLINK_CALL_STUB_SIZE
in glink_vma calculation.
(struct ppc_link_hash_table): Add global_entry section pointer.
(create_linkage_sections): Create separate section for global
entry stubs.
(PPC_LO, PPC_HI, PPC_HA): Move earlier.
(size_global_entry_stubs): Handle sizing for aligned stubs.
(ppc64_elf_size_dynamic_sections): Handle global_entry alloc,
and don't stash end of glink branch table in rawsize.
(ppc_build_one_stub): Rewrite stub size calculations.
(build_global_entry_stubs): Use new section.
(ppc64_elf_build_stubs): Don't pad __glink_PLTresolve with nops.
Build lazy link stubs out to end of section. Build global entry
stubs in new section.
gold/
* options.h (plt_align): Support for PowerPC32 too.
* powerpc.cc (Stub_table::stub_align): Heed --plt-align for 32-bit.
(Stub_table::plt_call_size, branch_stub_size): Tidy.
(Stub_table::plt_call_align): Implement using stub_align.
(Output_data_glink::global_entry_align): New function.
(Output_data_glink::global_entry_off): New function.
(Output_data_glink::global_entry_address): Use global_entry_off.
(Output_data_glink::pltresolve_size): New function, replacing
pltresolve_size_ constant. Update all uses.
(Output_data_glink::add_global_entry): Align offset.
(Output_data_glink::set_final_data_size): Use global_entry_align.
(Stub_table::do_write): Don't pad __glink_PLTrelsolve with nops.
Tidy stub output. Use global_entry_off.
ld/
* emultempl/ppc32elf.em (params): Init new field.
(enum ppc32_opt): New enum to define OPTION_* values. Add
OPTION_PLT_ALIGN and OPTION_NO_PLT_ALIGN.
(PARSE_AND_LIST_LONGOPTS): Handle new options.
(PARSE_AND_LIST_ARGS_CASES): Likewise.
(PARSE_AND_LIST_OPTIONS): Likewise. Break up help output.
* emultempl/ppc64elf.em (ppc_add_stub_section): Init alignment
correctly for negative --plt-stub-align.
* testsuite/ld-powerpc/elfv2exe.d,
* testsuite/ld-powerpc/elfv2so.d,
* testsuite/ld-powerpc/relbrlt.d,
* testsuite/ld-powerpc/relbrlt.s,
* testsuite/ld-powerpc/tlsexe.d,
* testsuite/ld-powerpc/tlsexe.r,
* testsuite/ld-powerpc/tlsexe32.d,
* testsuite/ld-powerpc/tlsexe32.g,
* testsuite/ld-powerpc/tlsexe32.r,
* testsuite/ld-powerpc/tlsexetoc.d,
* testsuite/ld-powerpc/tlsexetoc.r,
* testsuite/ld-powerpc/tlsopt5_32.d,
* testsuite/ld-powerpc/tlsso.d,
* testsuite/ld-powerpc/tlstocso.d: Update for changed stub order.
PR 22042 complained that garbage text was being printed in the help
for the -fuse-ld option; this was caused by passing an empty string
to the gettext() function, which sometimes returns garbage when passed
an empty string. The quick fix was to replace "" with NULL as the helparg,
but that changed the parsing of the option, as gold uses the helparg to
determine whether an option takes an argument. This patch adds a
non-empty helparg string to fix both problems.
gold/
PR gold/22694
* options.h (-fuse-ld): Add correct helparg.
We never need to resolve_forwards() a symbol found by hash table lookup
such as target->tls_get_addr_opt() but we do potentially need to do so
for random symbols seen on relocs. So these calls were in the wrong
order, resulting in missing stubs and an assertion failure.
PR 22602
* powerpc.cc (Target_powerpc::Branch_info::mark_pltcall): Resolve
forwards before replacing __tls_get_addr.
(Target_powerpc::Branch_info::make_stub): Likewise.
Gold plugins may wish to further process an input file added by a plugin. For
example, the plugin may need to assign a unique segment for sections in a
plugin-generated input file. This patch adds a plugin callback that the linker
will call when reading symbols from a new input file added after the
all_symbols_read event (i.e. an input file added by a plugin).
2017-12-11 Stephen Crane <sjc@immunant.com>
* plugin-api.h: Add new plugin hook to allow processing of input
files added by a plugin.
(ld_plugin_new_input_handler): New function hook type.
(ld_plugin_register_new_input): New interface.
(LDPT_REGISTER_NEW_INPUT_HOOK): New enum val.
(tv_register_new_input): New member.
* plugin.cc (Plugin::load): Include hooks for register_new_input
in transfer vector.
(Plugin::new_input): New function.
(register_new_input): New function.
(Plugin_manager::claim_file): Call Plugin::new_input if in
replacement phase.
* plugin.h (Plugin::set_new_input_handler): New function.
* testsuite/plugin_new_section_layout.c: New plugin to test
new_input plugin API.
* testsuite/plugin_final_layout.sh: Add new input test.
* testsuite/Makefile.am (plugin_layout_new_file): New test case.
* testsuite/Makefile.in: Regenerate.
This is a partial fix for the gold testsuite failures documented in
PR 21090. The use of -fpie triggers some mov-to-lea optimizations that
are not compatible with incremental linking, so those optimizations need
to be disabled. We also diagnose the attempt to use -pie with incremental
linking, and force -no-pie for the incremental tests in case the build has
been configured to have GCC pass -pie all the time.
We still have a problem where compiling with -fpie results in some GOT
entries even when linking with -no-pie. This combination still causes test
failures because we are not updating the GOT entries in an incremental update
link.
gold/
PR gold/21090
* incremental.cc (Sized_relobj_incr::do_relocate): Fix comment.
* options.cc (General_options::finalize): Disallow -pie with
incremental linking.
* x86_64.cc (Target_x86_64::Scan::local): Don't do mov-to-lea
or callq-to-direct optimizations for incremental links.
(Target_x86_64::Scan::global): Likewise.
(Target_x86_64::Relocate::relocate): Likewise.
* testsuite/Makefile.am (incremental_test): Force -no-pie.
(incremental_test_2): Likewise.
(incremental_test_3): Likewise.
(incremental_test_4): Likewise.
(incremental_test_5): Likewise.
(incremental_test_6): Likewise.
(incremental_copy_test): Likewise.
(incremental_common_test_1): Likewise.
(incremental_comdat_test_1): Likewise.
* testsuite/Makefile.in: Regenerate.
With the new compiler, we're running out of patch space for the .eh_frame
section. To workaround that issue, we compile the before and after versions
both with no unwind tables.
gold/
PR gold/22309
* testsuite/Makefile.am (two_file_test_1_v1_ndebug.o): Compile with
no EH information.
(two_file_test_1_ndebug.o): Likewise.
* testsuite/Makefile.in: Regenerate.
* testsuite/two_file_test_1.cc: Touch to force recompilation with new
flags.
* testsuite/two_file_test_1_v1.cc: Likewise.
The problem is that while the command line isn't trivially empty,
it contains no input files. As gold tries to configure the number
of threads to use based on the number of input files, this causes
the assertion failure above. Fix this problem by making the logic
in gold.cc more robust and also adding a better error message
about --start-lib to options.cc.
gold/
PR gold/22406
* gold.cc (queue_initial_tasks) Check for number of real input files.
* options.cc (Command_line::process) Check for unterminated --start-lib
options.
* testsuite/Makefile.am: Add new test script.
* testsuite/Makefile.in: Regenerate.
* testsuite/check_empty_command_lines.sh: New test script.
If a shared library contains an undefined symbol and LTO adds
a new reference to that same undefined symbol, the reference in the new
object added by the plugin would not trigger a rescan of the archive
containing the symbol.
2017-11-17 Stephen Crane <sjc@immunant.com>
gold/
PR gold/22448
* symtab.cc (Symbol_table::add_from_object): Only rescan for
undefined symbols in regular, not dynamic, objects.
The addresses of erratum stubs can be changed by relaxation passes, and
need to be updated.
gold/
PR gold/20765
* aarch64.cc (Aarch64_relobj::update_erratum_address): New method.
(AArch64_relobj::scan_errata): Update addresses in stub table after
relaxation pass.
I checked over the results of applying --fix-cortex-a53-843419 to
a very large program (gitit) with two stub tables and thousands
of erratum fixes. I noticed that all the erratum_stubs were being
created but about 1/3 of them were being skipped over by
fix_errata_and_relocate_erratum_stubs(). By skipped over I mean
no branch relocation or adrp -> adr transformation was applied to
the erratum address, leaving the erratum_stub unreachable, and
with a branch with a 0 immediate.
The root cause of the skipped over erratum_stubs is
Erratum_stub::invalidate_erratum_stub() that is used to set
relobj_ to NULL when an erratum_stub has been processed.
Unfortunately relobj_ is used in operator<() so altering relobj
makes the results from erratum_stubs_.lower_bound() as used in
find_erratum_stubs_for_input_section() unreliable.
2017-11-30 Peter Smith <peter.smith@linaro.org>
Cary Coutant <ccoutant@gmail.com>
gold/
PR gold/20765
* aarch64.cc (Erratum_stub::invalidate_erratum_stub): Use erratum_insn_
instead of relobj_ to invalidate the stub.
(Erratum_stub::is_invalidated_erratum_stub): Likewise.
Stephen Crane