ELFv2 needs to create plt entries in a non-PIC executable for an
address reference to a function defined in a shared object. It's
possible that an object file has no features that distinguish it as
ELFv1 or ELFv2, eg. an object only containing data. Such files need
to be handled like those that are known to be ELFv2.
However, this unnecessarily creates plt entries for the analogous
ELFv1 case, so arrange to set output abi version earlier, and use the
output abi version to further distinguish ambiguous input files.
bfd/
* elf64-ppc.c (ppc64_elf_check_relocs): Account for possibly
needed plt entries when taking the address of functions for
abiversion == 0 (ie. unknown) as well as abiversion == 2.
Move opd setup and abiversion checks to..
(ppc64_elf_before_check_relocs): ..here. Renamed from
ppc64_elf_process_dot_syms. Set output abiversion from input and
input abiversion from output, if either is not set.
(ppc64_elf_merge_private_bfd_data): Don't merge flags here.
(elf_backend_check_directives): Update.
ld/testsuite/
* ld-powerpc/startv1.s, * ld-powerpc/startv2.s, * ld-powerpc/funref.s,
* ld-powerpc/funv1.s, * ld-powerpc/funv2.s,
* ld-powerpc/ambiguousv1.d, * ld-powerpc/ambiguousv2.d: New test files.
* ld-powerpc/powerpc.exp: Run new tests.
R_PPC64_ADDR16 is used in three contexts:
- .short data relocation
- 16-bit signed insn fields, eg. addi
- 16-bit unsigned insn fields, eg. ori
In the first case we want to allow both signed and unsigned 16-bit
values, the latter two ought to error if the field exceeds the range
of values allowed for 16-bit signed and unsigned integers
respectively. These conflicting requirements meant that ld had to
choose the least restrictive overflow checks, and thus it is possible
to construct testcases where an addi field overflows but is not
reported by ld. Many relocations dealing with 16-bit insn fields have
this problem. What's more, some relocations that are only ever used
for signed fields of instructions woodenly copied the lax overflow
checking of R_PPC64_ADDR16.
bfd/
* elf64-ppc.c (ppc64_elf_howto_raw): Use complain_overflow_signed
for R_PPC64_ADDR14, R_PPC64_ADDR14_BRTAKEN, R_PPC64_ADDR14_BRNTAKEN,
R_PPC64_SECTOFF, R_PPC64_ADDR16_DS, R_PPC64_SECTOFF_DS,
R_PPC64_REL16 entries. Use complain_overflow_dont for R_PPC64_TOC.
(ppc64_elf_relocate_section): Modify overflow test for 16-bit
fields in instructions to signed/unsigned according to whether
the field takes a signed or unsigned value.
gold/
* powerpc.cc (Powerpc_relocate_functions::Overflow_check): Add
CHECK_UNSIGNED, CHECK_LOW_INSN, CHECK_HIGH_INSN.
(Powerpc_relocate_functions::has_overflow_unsigned): New function.
(Powerpc_relocate_functions::has_overflow_bitfield,
overflowed): Use the above.
(Target_powerpc::Relocate::relocate): Correct overflow checking
for a number of relocations. Modify overflow test for 16-bit
fields in instructions to signed/unsigned according to whether
the field takes a signed or unsigned value.
This adds support for "func@localentry", an expression that returns the
ELFv2 local entry point address of function "func". I've excluded
dynamic relocation support because that obviously would require glibc
changes.
include/elf/
* ppc64.h (R_PPC64_REL24_NOTOC, R_PPC64_ADDR64_LOCAL): Define.
bfd/
* elf64-ppc.c (ppc64_elf_howto_raw): Add R_PPC64_ADDR64_LOCAL entry.
(ppc64_elf_reloc_type_lookup): Support R_PPC64_ADDR64_LOCAL.
(ppc64_elf_check_relocs): Likewise.
(ppc64_elf_relocate_section): Likewise.
* Add BFD_RELOC_PPC64_ADDR64_LOCAL.
* bfd-in2.h: Regenerate.
* libbfd.h: Regenerate.
gas/
* config/tc-ppc.c (ppc_elf_suffix): Support @localentry.
(md_apply_fix): Support R_PPC64_ADDR64_LOCAL.
ld/testsuite/
* ld-powerpc/elfv2-2a.s, ld-powerpc/elfv2-2b.s: New files.
* ld-powerpc/elfv2-2exe.d, ld-powerpc/elfv2-2so.d: New files.
* ld-powerpc/powerpc.exp: Run new test.
elfcpp/
* powerpc.h (R_PPC64_REL24_NOTOC, R_PPC64_ADDR64_LOCAL): Define.
gold/
* powerpc.cc (Target_powerpc::Scan::local, global): Support
R_PPC64_ADDR64_LOCAL.
(Target_powerpc::Relocate::relocate): Likewise.
This patch allows the user to override powerpc64-ld's default for
providing linker generated register save and restore functions as used
by gcc -Os code. Normally these are not provided by ld -r, so Linux
kernel modules have needed to include their own copies.
bfd/
* elf64-ppc.h (struct ppc64_elf_params): Add save_restore_funcs.
* elf64-ppc.c (ppc64_elf_func_desc_adjust): Use it to control
provision of out-of-line register save/restore routines.
ld/
* emultempl/ppc64elf.em (params): Init new field.
(ppc_create_output_section_statements): Set params.save_restore_funcs
default.
(PARSE_AND_LIST_*): Add support for --save-restore-funcs and
--no-save-restore-funcs.
Moves assorted variables used to communicate between ld and bfd into
a struct, hooks it into the bfd link_hash_table early, and removes
all other places where such variables were passed piecemeal.
bfd/
* elf64-ppc.h (struct ppc64_elf_params): Define.
(ppc64_elf_init_stub_bfd, ppc64_elf_edit_opd, ppc64_elf_tls_setup,
ppc64_elf_setup_section_lists, ppc64_elf_size_stubs,
ppc64_elf_build_stubs): Update prototype.
* elf64-ppp.c (struct ppc_link_hash_table): Add params, delete other
fields now in params. Adjust code throughout file.
(ppc64_elf_init_stub_bfd): Delete "abfd" parameter, add "params".
Save params pointer in htab.
(ppc64_elf_edit_opd, ppc64_elf_tls_setup,
ppc64_elf_setup_section_lists, ppc64_elf_size_stubs,
ppc64_elf_build_stubs): Remove parameters now in "params".
ld/
* emultemps/ppc64elf.em (params): New static struct replacing
various other static vars. Adjust code throughout file.
For powerpc64 as HJ did earlier for other ELF targets, and a tidy.
PR gold/15530
* elf64-ppc.c (ppc64_elf_gc_mark_dynamic_ref): Support
--export-dynamic and --dynamic-list marking of symbols.
* elflink.c (bfd_elf_gc_mark_dynamic_ref_symbol): Reorder
cheap tests first.
bfd/
2014-02-04 Jan Kratochvil <jan.kratochvil@redhat.com>
* coff-rs6000.c (xcoff_write_archive_contents_big): Free OFFSETS in
return paths. Three times.
* elf64-ppc.c (ppc64_elf_link_hash_table_create): Free HTAB in all
return paths.
(ppc64_elf_tls_optimize): Free TOC_REF in return path.
(ppc64_elf_edit_toc): Free USED in return path.
ELFv2 needs fewer relocs to annotate plt call stubs. I correctly
allocated a smaller buffer and wrote the proper relocs, but stupidly
bumped the reloc count as for ELFv1.
* elf64-ppc.c (ppc_build_one_stub): Correct reloc count passed
to get_relocs for ELFv2.
I don't know what I was thinking here to omit the save of r2.
Possibly I was looking at -msave-toc-indirect code at the time, where
r2 is saved in the function prologue.
* elf64-ppc.c (ppc_build_one_stub <ppc_stub_plt_branch_r2off>):
Don't omit saving of r2 for ELFv2. Don't addi 2,2,0.
(ppc_size_one_stub <ppc_stub_plt_branch_r2off>): Adjust to suit.
With -mcmodel=medium we can't assume that a -R object doesn't use
toc-relative addressing if there's no toc. Lots of things are
accessed via r2, not just the toc/got section. Also, testing for
.opd is plain wrong for ELFv2.
* elf64-ppc.c (ppc64_elf_link_just_syms): Remove .got check.
Handle ELFv2.
Some places in elf64-ppc.c carelessly used SYMBOL_CALLS_LOCAL when
the proper test is SYMBOL_REFERENCES_LOCAL for cases where we take the
address of a protected symbol. This works OK for function descriptors
but not for ELFv2. Setting symbols to their global entry stub a
little earlier is to ensure _bfd_elf_hash_symbol allows such symbols
in .gnu.hash.
* elf64-ppc.c (ppc64_elf_edit_toc): Use SYMBOL_REFERENCES_LOCAL
here, not SYMBOL_CALLS_LOCAL.
(ppc64_elf_relocate_section): Likewise.
(size_global_entry_stubs): Set undefined symbols on their global
entry stubs here..
(build_global_entry_stubs): ..rather than here.
(ppc64_elf_build_stubs): Don't reset glink->size before calling
build_global_entry_stubs.
I can't see any good reason why anyone would want a dynamic .TOC., so
hide it in a way that is respected by _bfd_elf_export_symbol. This
also fixes an abort in relocate_section on not finding sreloc for .TOC.
* elf64-ppc.c (ppc64_elf_func_desc_adjust): Make .TOC. defined and
hidden.
(ppc64_elf_set_toc): Adjust.
These shortcuts to dynamic sections in ppc_link_hash_table predated
their geneneric elf hash table equivalents.
* elf64-ppc.c (struct ppc_link_hash_table): Remove got, plt, relplt,
iplt, reliplt. Update all references to use elf.sgot, elf.splt,
elf.srelplt, elf.iplt and elf.irelplt.
Changing addis r2,r12,..; addi r2,r2,.. to lis r2,..; addi r2,r2..
in non-PIC executables has the benefit of removing a dependency on r12.
bfd/
* elf64-ppc.c (ppc64_elf_relocate_section): Edit global entry
prologue to non-PIC in non-PIC executables.
ld/testsuite/
* ld-powerpc/elfv2exe.d: Adjust for non-PIC global entry.
In a non-pic executable, ELFv2 like other targets, needs to emit a plt
entry even for non-call references to functions defined in shared
libraries, and define the function on the plt code.
* elf64-ppc.c (ppc64_elf_copy_indirect_symbol): Copy
pointer_equality_needed flag.
(ppc64_elf_check_relocs): For ELFv2 arrange to emit plt
entries for references to functions in shared libraries on
non-call relocs.
(readonly_dynrelocs): Split into function of the same name and..
(maybe_set_textrel): ..this new function. Update call.
(ppc64_elf_adjust_dynamic_symbol): Don't emit dynrelocs for
ELFv2 in most cases if we have a plt entry. Use new
readonly_relocs.
(allocate_dynrelocs): For ELFv2, don't allocate dynreloc space
for ifunc in static executables.
(size_global_entry_stubs): New function.
(ppc64_elf_size_dynamic_sections): Call size_global_entry_stubs.
Save end of glink branch table.
(ppc64_elf_hash_symbol): New function.
(build_global_entry_stubs): New function.
(ppc64_elf_build_stubs): Call build_global_entry_stubs. Adjust
glink sizing.
(ppc64_elf_relocate_section): Tidy plt16/32/64 reloc code.
(ppc64_elf_finish_dynamic_symbol): For ELFv2, adjust symbols
defined on plt code.
Every function has a nominal toc pointer value, even if it isn't used,
so set toc_off for every code section to the value used in that object
file. The thinking here was that if a code section didn't use the toc
it could use the previous object file's toc pointer value. It can,
but doing so is only a gain if functions in that section are called
mostly from previous objects sharing the same toc. We lose if the
functions in question are called mostly from the current object or
following objects, and it's a good bet they will probably mostly be
called from the current object.
* elf64-ppc.c (ppc64_elf_next_input_section): Always set toc_off
to value for object file.
This removes the DT_PPC_TLSOPT/DT_PPC64_TLSOPT dynamic tag and replaces
it with DT_PPC_OPT/DT_PPC64_OPT tag to provide the same functionality
and more. This isn't backwards compatible, but the TLSOPT tag hasn't
been used since the tls optimisation support was never submitted to
glibc.
/include/elf/
* ppc.h (DT_PPC_TLSOPT): Delete.
(DT_PPC_OPT, PPC_OPT_TLS): Define.
* ppc64.h (DT_PPC64_TLSOPT): Delete.
(DT_PPC64_OPT, PPC64_OPT_TLS, PPC64_OPT_MULTI_TOC): Define.
bfd/
* elf32-ppc.c (ppc_elf_size_dynamic_sections): Use new DT_PPC_OPT
tag to specify tls optimisation.
* elf64-ppc.c (ppc64_elf_size_dynamic_sections): Likewise.
(ppc64_elf_finish_dynamic_sections): Specify whether multiple
toc pointers are used via DT_PPC64_OPT.
binutils/
* readelf.c (get_ppc_dynamic_type): Replace PPC_TLSOPT with PPC_OPT.
(get_ppc64_dynamic_type): Replace PPC64_TLSOPT with PPC64_OPT.
The toc pointer save slot changes on ELFv2 from 40(1) to 24(1).
* elf64-ppc.c (STK_LR, STK_TOC, STK_LINKER): Define.
(savegpr0_tail, restgpr0_tail, savefpr0_tail, restfpr0_tail)
build_plt_stub, build_tls_get_addr_stub, ppc_build_one_stub,
ppc64_elf_relocate_section): Use new defines.
An ELFv2 PLT entry is simply the address of the target function rather
than three (or two) words to specify entry, toc and static chain. PLT
call stubs are correspondingly simpler and need no thread safety
barrier. The glink resolver stub and branch table also is simplified,
a change that could be applied to ELFv1 too, but isn't as yet.
* elf64-ppc.c (PLT_ENTRY_SIZE, PLT_INITIAL_ENTRY_SIZE): Add htab
parameter and adjust for ELFv2. Update all uses.
(PLT_CALL_STUB_SIZE): Delete.
(ppc64_elf_get_synthetic_symtab): Support new glink layout.
(allocate_dynrelocs): Likewise.
(plt_stub_size, build_plt_stub): Adjust for ELFv2.
(get_r2off): Return 0 for ELFv2 -R.
(ppc_build_one_stub, ppc_size_one_stub): Adjust for ELFv2.
(ppc64_elf_size_stubs): Likewise.
(ppc64_elf_build_stubs): Add new ELFv2 glink.
This defines the ELF symbol st_other field used to encode the number
of instructions between a function "global entry" and its "local entry",
and adds support related to the local entry offset.
include/elf/
* ppc64.h (STO_PPC64_LOCAL_BIT, STO_PPC64_LOCAL_MASK): Define.
(ppc64_decode_local_entry, ppc64_encode_local_entry): New functions.
(PPC64_LOCAL_ENTRY_OFFSET, PPC64_SET_LOCAL_ENTRY_OFFSET): Define.
bfd/
* elf64-ppc.c (struct ppc_stub_hash_entry): Add "other".
(stub_hash_newfunc): Init new ppc_stub_hash_entry field, and one
we forgot, "plt_ent".
(ppc64_elf_add_symbol_hook): Check ELFv1 objects don't have
st_other bits only valid in ELFv2.
(ppc64_elf_merge_symbol_attribute): New function.
(ppc_type_of_stub): Add local_off param to test branch range.
(ppc_build_one_stub): Adjust destinations for ELFv2 locals.
(ppc_size_one_stub, toc_adjusting_stub_needed): Similarly.
(ppc64_elf_size_stubs): Pass local_off to ppc_type_of_stub.
Set "other" field.
(ppc64_elf_relocate_section): Adjust destination for ELFv2 local
calls.
gas/
* config/tc-ppc.c (md_pseudo_table): Add .localentry.
(ppc_elf_localentry): New function.
(ppc_force_relocation): Force relocs on all branches to localenty
symbols.
(ppc_fix_adjustable): Don't reduce such symbols to section+offset.
binutils/
* readelf.c (get_ppc64_symbol_other): New function.
(get_symbol_other): Use it for EM_PPC64.
Defines bits in ELF e_flags to differentiate ELFv2 objects from ELFv2,
adds .abiversion directive to explicitly choose the ABI, and code to
check and automatically select ABI.
include/elf/
* ppc64.h (EF_PPC64_ABI): Define.
bfd/
* elf64-ppc.c (abiversion, set_abiversion): New functions.
(ppc64_elf_get_synthetic_symtab): Handle ELFv2 objects without .opd.
(struct ppc_link_hash_table): Add opd_abi.
(ppc64_elf_check_relocs): Check no .opd with ELFv2.
(ppc64_elf_merge_private_bfd_data): New function.
(ppc64_elf_print_private_bfd_data): New function.
(ppc64_elf_tls_setup): Set htab->opd_abi.
(ppc64_elf_size_dynamic_sections): Don't emit OPD related dynamic
tags for ELFv2.
(ppc_build_one_stub): Use R_PPC64_IRELATIVE for ELFv2 ifunc.
(ppc64_elf_finish_dynamic_symbol): Likewise
binutils/
* readelf.c (get_machine_flags): Display ABI version for EM_PPC64.
gas/
* config/tc-ppc.c: Include elf/ppc64.h.
(ppc_abiversion): New variable.
(md_pseudo_table): Add .abiversion.
(ppc_elf_abiversion, ppc_elf_end): New functions.
* config/tc-ppc.h (md_end): Define.
This change is to support the new ELFv2 ABI, which uses the value in
r12 on function entry to calculate the got/toc pointer.
bfd/
* elf64-ppc.c (build_plt_stub): Switch stubs to use r11 as base
reg and r12 as destination.
(ppc_build_one_stub): Likewise.
(ppc64_elf_build_stubs): Likewise for glink.
ld/testsuite/
* ld-powerpc/tls.s: Add proper .opd entry for _start.
* ld-powerpc/tlstoc.s: Likewise.
* ld-powerpc/relbrlt.d: Update for changed stubs.
* ld-powerpc/tls.d: Update for changed stubs and _start .opd entry.
* ld-powerpc/tls.g: Likewise.
* ld-powerpc/tlsexe.d: Likewise.
* ld-powerpc/tlsexe.g: Likewise.
* ld-powerpc/tlsexe.r: Likewise.
* ld-powerpc/tlsexetoc.d: Likewise.
* ld-powerpc/tlsexetoc.g: Likewise.
* ld-powerpc/tlsexetoc.r: Likewise.
* ld-powerpc/tlsso.d: Likewise.
* ld-powerpc/tlsso.g: Likewise.
* ld-powerpc/tlsso.r: Likewise.
* ld-powerpc/tlstoc.d: Likewise.
* ld-powerpc/tlstoc.g: Likewise.
* ld-powerpc/tlstocso.d: Likewise.
* ld-powerpc/tlstocso.g: Likewise.
* ld-powerpc/tlstocso.r: Likewise.
This changes the behaviour of @h and @ha on PowerPC64 to report errors
on 32-bit overflow. The motivation for this change is that on
PowerPC64, most uses of @h and @ha modifiers and their corresponding
relocations are to build up 32-bit offsets. We'd like to know when
such offsets overflow. Only rarely do people use @h or @ha with the
high 32-bit modifiers to build a 64-bit constant. Those uses will now
need to use two new modifiers, @high and @higha, if the constant isn't
known at assembly time. For now, we won't report overflow at assembly
time..
This also fixes an error when applying some of the HIGHER and HIGHEST
relocations.
include/elf/
* ppc64.h (R_PPC64_ADDR16_HIGH, R_PPC64_ADDR16_HIGHA,
R_PPC64_TPREL16_HIGH, R_PPC64_TPREL16_HIGHA,
R_PPC64_DTPREL16_HIGH, R_PPC64_DTPREL16_HIGHA): New.
(IS_PPC64_TLS_RELOC): Match new tls relocs.
bfd/
* reloc.c (BFD_RELOC_PPC64_ADDR16_HIGH, BFD_RELOC_PPC64_ADDR16_HIGHA,
BFD_RELOC_PPC64_TPREL16_HIGH, BFD_RELOC_PPC64_TPREL16_HIGHA,
BFD_RELOC_PPC64_DTPREL16_HIGH, BFD_RELOC_PPC64_DTPREL16_HIGHA): New.
* elf64-ppc.c (ppc64_elf_howto_raw): Add entries for new relocs.
Make all _HA and _HI relocs report signed overflow.
(ppc64_elf_reloc_type_lookup): Handle new relocs.
(must_be_dyn_reloc, ppc64_elf_check_relocs): Likewise.
(dec_dynrel_count, ppc64_elf_relocate_section): Likewise.
(ppc64_elf_relocate_section): Don't apply 0x8000 adjust to
R_PPC64_TPREL16_HIGHER, R_PPC64_TPREL16_HIGHEST,
R_PPC64_DTPREL16_HIGHER, and R_PPC64_DTPREL16_HIGHEST.
* libbfd.h: Regenerate.
* bfd-in2.h: Regenerate.
gas/
* config/tc-ppc.c (SEX16): Don't mask.
(REPORT_OVERFLOW_HI): Define as zero.
(ppc_elf_suffix): Support @high, @higha, @dtprel@high, @dtprel@higha,
@tprel@high, and @tprel@higha modifiers.
(md_assemble): Ignore X_unsigned when applying 16-bit insn fields.
Add (disabled) code to check @h and @ha reloc overflow for powerpc64.
Handle new relocs.
(md_apply_fix): Similarly.
elfcpp/
* powerpc.h (R_PPC64_ADDR16_HIGH, R_PPC64_ADDR16_HIGHA,
R_PPC64_TPREL16_HIGH, R_PPC64_TPREL16_HIGHA,
R_PPC64_DTPREL16_HIGH, R_PPC64_DTPREL16_HIGHA): Define.
gold/
* powerpc.cc (Target_powerpc::Scan::check_non_pic): Handle new relocs.
(Target_powerpc::Scan::global, local): Likewise.
(Target_powerpc::Relocate::relocate): Likewise. Check for overflow
on all ppc64 @h and @ha relocs.
* elf64-ppc.c (struct ppc_stub_hash_entry): Delete "addend".
(ppc64_elf_size_stubs): Don't set "addend".
(ppc64_elf_relocate_section): Don't allow calls via
toc-adjusting stubs without a following nop even in an
executable, except for self-calls and both libc_start_main
and .libc_start_main.
gold/
* powerpc.cc (Target_powerpc::Relocate::relocate): Update self-call
comment.
* elf64-ppc.c (ppc64_elf_relocate_section): Set "relocation" for
.TOC. after relocatable check.
gas/
* config/tc-ppc.c (ppc_elf_adjust_symtab): Don't make .TOC. weak.
* elf64-ppc.h (ppc64_elf_toc): Delete.
(ppc64_elf_set_toc): Declare.
* elf64-ppc.c (ppc64_elf_toc_reloc): Replace call to ppc64_elf_toc
with call the ppc64_elf_set_toc.
(ppc64_elf_toc_ha_reloc, ppc64_elf_toc64_reloc): Likewise.
(ppc64_elf_start_multitoc_partition): Likewise.
(struct ppc_link_hash_table): Delete dot_toc_dot. Replace all uses
with elf.hgot.
(ppc64_elf_process_dot_syms): Don't make a fake function descriptor
for ".TOC.".
(ppc64_elf_check_relocs): Mark sections with a reference to .TOC.
as needing a toc pointer.
(ppc64_elf_size_stubs): Don't set dot_toc_dot here.
(ppc64_elf_set_toc): Rename from ppc64_elf_toc. Add info param.
Set elf.hgot value.
ld/
* emultempl/ppc64elf.em: (ppc_layout_sections_again): Call
ppc64_elf_set_toc rather than ppc64_elf_toc/_bfd_set_gp_value.
(gld${EMULATION_NAME}_after_allocation): Likewise.
(ppc64_elf_check_relocs): Separate dynrel counts for local syms
into ifunc and non-ifunc.
(dec_dynrel_count): Pass in sym rather than sym_sec. Handle
separate ifunc/non-ifunc dynrel counts.
(allocate_got): Always use reliplt for ifunc.
(allocate_dynrelocs): Likewise.
(ppc64_elf_size_dynamic_sections): Likewise.
(ppc64_elf_layout_multitoc): Likewise.
(ppc64_elf_relocate_section): Likewise.
"relocation" in error messages throughout file.
(ppc64_elf_relocate_section): Remove sibling call error message,
replace with "call lacks nop". Specially report errors for
branches to function entry points via OPD lookup and branches
to stubs. Remove NULL symbol handling now done by %T.
