This is the one that causes ld segfaults between 2019-10-04 and
2019-10-07. Bug introduced with f749f26eea, fixed by 93370e8e7b.
* testsuite/ld-powerpc/localgot.s,
* testsuite/ld-powerpc/localgot.d: New test.
* testsuite/ld-powerpc/powerpc.exp: Run it.
This patch adds some --no-tls-optimize tests and performs some of the
existing dynamic tests with tls markers in order to catch any
regression in PLT counting.
* testsuite/ld-powerpc/tlsexe.r: Adjust for added TLSMARK symbol.
* testsuite/ld-powerpc/tlsexe32.r: Likewise.
* testsuite/ld-powerpc/tlsso.r: Likewise.
* testsuite/ld-powerpc/tlsso32.r: Likewise.
* testsuite/ld-powerpc/tls32no.d,
* testsuite/ld-powerpc/tls32no.g: New test files.
* testsuite/ld-powerpc/tlsexe32no.d,
* testsuite/ld-powerpc/tlsexe32no.g,
* testsuite/ld-powerpc/tlsexe32no.r: New test files.
* testsuite/ld-powerpc/tlsexeno.d,
* testsuite/ld-powerpc/tlsexeno.g,
* testsuite/ld-powerpc/tlsexeno.r: New test files.
* testsuite/ld-powerpc/tlsexetocno.d,
* testsuite/ld-powerpc/tlsexetocno.g: New test files.
* testsuite/ld-powerpc/tlsno.d,
* testsuite/ld-powerpc/tlsno.g: New test files.
* testsuite/ld-powerpc/tlstocno.d,
* testsuite/ld-powerpc/tlstocno.g: New test files.
* testsuite/ld-powerpc/powerpc.exp: Run new tests.
1) GOT entries generated for any of the GOT TLS relocations don't need
dynamic relocations for locally defined symbols in PIEs. In the case
of a tls_index doubleword, the dtpmod entry is known to be 1, and the
dtprel entry is also known at link time and relative. Similarly,
dtprel and tprel words are known at link time and relative. (GOT
entries for other than TLS symbols are not relative and thus need
dynamic relocations in PIEs.)
2) Local dynamic TLS code is really only meant for accesses local to
the current binary. There was a cheapskate test for this before using
the common tlsld_got slot, but the test wasn't exactly correct and
might confuse anyone looking at the code. The proper test,
SYMBOL_REFERENCES_LOCAL isn't so expensive that it should be avoided.
3) The same cheap test for local syms when optimising TLS sequences
should be SYMBOL_REFERENCES_LOCAL too.
bfd/
* elf64-ppc.c (ppc64_elf_check_relocs): Move initialisation of vars.
(ppc64_elf_tls_optimize): Correct is_local condition.
(allocate_got): Don't reserve dynamic relocations for any of the
tls got relocs in PIEs when the symbol is local.
(allocate_dynrelocs): Correct validity test for local sym using
tlsld_got slot.
(ppc64_elf_size_dynamic_sections): Don't reserve dynamic relocations
for any of the tls got relocs in PIEs.
(ppc64_elf_layout_multitoc): Likewise.
(ppc64_elf_relocate_section): Correct validity test for local sym
using tlsld_got slot. Don't emit dynamic relocations for any of
the tls got relocs in PIEs when the symbol is local.
* elf32-ppc.c (ppc_elf_tls_optimize): Correct is_local condition.
(got_relocs_needed): Delete.
(allocate_dynrelocs): Correct validity test for local sym using
tlsld_got slot. Don't reserve dynamic relocations for any of the
tls got relocs in PIEs when the symbol is local.
(ppc_elf_size_dynamic_sections): Don't reserve dynamic relocations
for any of the tls got relocs in PIEs.
(ppc_elf_relocate_section): Correct validity test for local sym
using tlsld_got slot. Don't emit dynamic relocations for any of
the tls got relocs in PIEs when the symbol is local.
ld/
* testsuite/ld-powerpc/tlsso.d: Adjust to suit tlsld_got usage change.
* testsuite/ld-powerpc/tlsso.g: Likewise.
* testsuite/ld-powerpc/tlsso.r: Likewise.
* testsuite/ld-powerpc/tlsso32.d: Likewise.
* testsuite/ld-powerpc/tlsso32.g: Likewise.
* testsuite/ld-powerpc/tlsso32.r: Likewise.
The loads and stores handled in the second instruction of a sequence
marked by R_PPC64_PCREL_OPT may be a prefix instruction. For example:
pld ra,symbol@got@pcrel
0:
pld rt,off(ra)
.reloc 0b-8,R_PPC64_PCREL_OPT,(.-8)-(0b-8)
can be optimised to
pld rt,symbol+off@pcrel
pnop
* elf64-ppc.c (xlate_pcrel_opt): Handle prefix loads and stores
in second instruction.
(ppc64_elf_relocate_section): Likewise.
This patch supports using pcrel instructions in TLS code sequences. A
number of new relocations are needed, gas operand modifiers to
generate those relocations, and new TLS optimisation. For
optimisation it turns out that the new pcrel GD and LD sequences can
be distinguished from the non-pcrel GD and LD sequences by there being
different relocations on the new sequence. The final "add ra,rb,13"
on IE sequences similarly needs a new relocation, or as I chose, a
modification of R_PPC64_TLS. On pcrel IE code, the R_PPC64_TLS points
one byte into the "add" instruction rather than being on the
instruction boundary.
GD:
pla 3,z@got@tlsgd@pcrel # R_PPC64_GOT_TLSGD34
bl __tls_get_addr@notoc(z@tlsgd) # R_PPC64_TLSGD and R_PPC64_REL24_NOTOC
edited to IE
pld 3,z@got@tprel@pcrel
add 3,3,13
edited to LE
paddi 3,13,z@tprel
nop
LD:
pla 3,z@got@tlsld@pcrel # R_PPC64_GOT_TLSLD34
bl __tls_get_addr@notoc(z@tlsld) # R_PPC64_TLSLD and R_PPC64_REL24_NOTOC
..
paddi 9,3,z2@dtprel
pld 10,z3@got@dtprel@pcrel
add 10,10,3
edited to LE
paddi 3,13,0x1000
nop
IE:
pld 9,z@got@tprel@pcrel # R_PPC64_GOT_TPREL34
add 3,9,z@tls@pcrel # R_PPC64_TLS at insn+1
ldx 4,9,z@tls@pcrel
lwax 5,9,z@tls@pcrel
stdx 5,9,z@tls@pcrel
edited to LE
paddi 9,13,z@tprel
nop
ld 4,0(9)
lwa 5,0(9)
std 5,0(9)
LE:
paddi 10,13,z@tprel
include/
* elf/ppc64.h (R_PPC64_TPREL34, R_PPC64_DTPREL34),
(R_PPC64_GOT_TLSGD34, R_PPC64_GOT_TLSLD34),
(R_PPC64_GOT_TPREL34, R_PPC64_GOT_DTPREL34): Define.
(IS_PPC64_TLS_RELOC): Include new tls relocs.
bfd/
* reloc.c (BFD_RELOC_PPC64_TPREL34, BFD_RELOC_PPC64_DTPREL34),
(BFD_RELOC_PPC64_GOT_TLSGD34, BFD_RELOC_PPC64_GOT_TLSLD34),
(BFD_RELOC_PPC64_GOT_TPREL34, BFD_RELOC_PPC64_GOT_DTPREL34),
(BFD_RELOC_PPC64_TLS_PCREL): New pcrel tls relocs.
* elf64-ppc.c (ppc64_elf_howto_raw): Add howtos for pcrel tls relocs.
(ppc64_elf_reloc_type_lookup): Translate pcrel tls relocs.
(must_be_dyn_reloc, dec_dynrel_count): Add R_PPC64_TPREL64.
(ppc64_elf_check_relocs): Support pcrel tls relocs.
(ppc64_elf_tls_optimize, ppc64_elf_relocate_section): Likewise.
* bfd-in2.h: Regenerate.
* libbfd.h: Regenerate.
gas/
* config/tc-ppc.c (ppc_elf_suffix): Map "tls@pcrel", "got@tlsgd@pcrel",
"got@tlsld@pcrel", "got@tprel@pcrel", and "got@dtprel@pcrel".
(fixup_size, md_assemble): Handle pcrel tls relocs.
(ppc_force_relocation, ppc_fix_adjustable): Likewise.
(md_apply_fix, tc_gen_reloc): Likewise.
ld/
* testsuite/ld-powerpc/tlsgd.d,
* testsuite/ld-powerpc/tlsgd.s,
* testsuite/ld-powerpc/tlsie.d,
* testsuite/ld-powerpc/tlsie.s,
* testsuite/ld-powerpc/tlsld.d,
* testsuite/ld-powerpc/tlsld.s: New tests.
* testsuite/ld-powerpc/powerpc.exp: Run them.
Just making room for a new tlsld test.
* testsuite/ld-powerpc/tlsldopt.d: Rename from tlsld.d.
* testsuite/ld-powerpc/tlsldopt.s: Rename from tlsld.s.
* testsuite/ld-powerpc/tlsldopt32.d: Rename from tlsld32.d.
* testsuite/ld-powerpc/tlsldopt32.s: Rename from tlsld32.s.
* testsuite/ld-powerpc/powerpc.exp: Update.
It is possible to create shared libraries on PowerPC using
-ftls-model=inital-exec or -ftls-model=local-exec. The first is half
reasonable, getting you a shared library that can't be dlopen'd but
otherwise is reasonable. The second is quite bad. Not only do you
lose being able to dlopen, the library also has dynamic text
relocations. Worse, the TPREL16_LO, TPREL16_HA and other TPREL16
dynamic relocs emitted were wrong, resulting in wrong values being
applied by ld.so.
Using the first TLS section symbol in dynamic relocations for local
TLS symbols doesn't work. It's wrong because TLS symbols used by TLS
relocs have values relative to the TLS segment, whereas the TLS
section symbols are addresses. This patch instead uses a symbol index
of zero which is used elsewhere by PowerPC on dynamic TLS relocs.
It's not strictly ABI compliant to use a non-TLS symbol with TLS
relocs but symbol index zero can be interpreted as "no symbol". Not
using the first TLS section symbol means it doesn't need to be dynamic.
The patch also fixes a further problem with PowerPC32 dynamic TPREL16*
relocs, which shouldn't have the symbol value in the addend as we do
for non-TLS symbols.
bfd/
* elflink.c (_bfd_elf_omit_section_dynsym_default): Don't keep
tls_sec.
(_bfd_elf_init_1_index_section): Prefer not using TLS sections.
(_bfd_elf_init_2_index_sections): Likewise.
* elf64-ppc.c (ppc64_elf_relocate_section): When emitting dynamic
relocations for local TLS symbols, use STN_UNDEF as the relocation
symbol.
* elf32-ppc.c (ppc_elf_relocate_section): Likewise, and don't
leave TLS symbol value in the addend.
ld/
* testsuite/ld-powerpc/tlsso.r: Update.
* testsuite/ld-powerpc/tlsso32.g: Update.
* testsuite/ld-powerpc/tlsso32.r: Update.
* testsuite/ld-powerpc/tlstocso.r: Update.
* testsuite/ld-cris/tls-dso-dtpoffd2.d: Update.
* testsuite/ld-cris/tls-dso-dtpoffd4.d: Update.
* testsuite/ld-cris/tls-dso-tpoffgotcomm1.d: Update.
* testsuite/ld-cris/tls-gd-1.d: Update.
* testsuite/ld-cris/tls-gd-1h.d: Update.
* testsuite/ld-cris/tls-gd-2.d: Update.
* testsuite/ld-cris/tls-gd-2h.d: Update.
* testsuite/ld-cris/tls-ie-10.d: Update.
* testsuite/ld-cris/tls-ie-11.d: Update.
* testsuite/ld-cris/tls-ie-8.d: Update.
* testsuite/ld-cris/tls-ie-9.d: Update.
* testsuite/ld-cris/tls-js1.d: Update.
* testsuite/ld-cris/tls-ld-4.d: Update.
* testsuite/ld-cris/tls-ld-5.d: Update.
* testsuite/ld-cris/tls-ld-6.d: Update.
* testsuite/ld-cris/tls-ld-7.d: Update.
* testsuite/ld-cris/tls-ldgd-14.d: Update.
* testsuite/ld-cris/tls-ldgd-15.d: Update.
* testsuite/ld-cris/tls-ldgdx-14.d: Update.
* testsuite/ld-cris/tls-ldgdx-15.d: Update.
* testsuite/ld-cris/tls-local-54.d: Update.
* testsuite/ld-cris/tls-local-60.d: Update.
* testsuite/ld-cris/tls-local-61.d: Update.
* testsuite/ld-cris/tls-local-63.d: Update.
* testsuite/ld-cris/tls-local-64.d: Update.
* testsuite/ld-cris/tls-ok-30.d: Update.
* testsuite/ld-cris/tls-ok-32.d: Update.
* testsuite/ld-cris/tls-ok-34.d: Update.
* testsuite/ld-mips-elf/tls-multi-got-1.got: Update.
* testsuite/ld-mips-elf/tls-multi-got-1.r: Update.
* testsuite/ld-mips-elf/tlsdyn-pie-o32.d: Update.
* testsuite/ld-mips-elf/tlsdyn-pie-o32.got: Update.
* testsuite/ld-mips-elf/tlslib-o32-hidden.got: Update.
* testsuite/ld-mips-elf/tlslib-o32-ver.got: Update.
* testsuite/ld-mips-elf/tlslib-o32.got: Update.
* testsuite/ld-s390/tlspic.rd: Update.
* testsuite/ld-s390/tlspic_64.rd: Update.
* testsuite/ld-sparc/tlssunnopic32.rd: Update.
* testsuite/ld-sparc/tlssunnopic64.rd: Update.
* testsuite/ld-sparc/tlssunpic32.rd: Update.
* testsuite/ld-sparc/tlssunpic64.rd: Update.
While the skiboot linker script bears some culpability in this PR,
it's also true that the GOT indirect to GOT relative optimisation for
16-bit offsets isn't safe. At least, it isn't safe to remove the GOT
entry based on distance between the GOT pointer and symbol calculated
from the preliminary layout. So this patch removes that optimisation,
and reduces the range allowed for 32-bit and 34-bit offsets.
PR 24704
bfd/
* elf64-ppc.c (R_PPC64_GOT16_DS): Don't set has_gotrel.
(ppc64_elf_edit_toc): Don't remove R_PPC64_GOT16_DS got entries.
Reduce range of offsets allowed for other GOT relocs.
ld/
* testsuite/ld-powerpc/elfv2exe.d: Update.
* testsuite/ld-powerpc/elfv2so.d: Update.
bfd/
* elf64-ppc.c (ppc64_elf_check_relocs): Set has_gotrel for
R_PPC64_GOT_PCREL34.
(xlate_pcrel_opt): New function.
(ppc64_elf_edit_toc): Handle R_PPC64_GOT_PCREL34.
(ppc64_elf_relocate_section): Edit GOT indirect to GOT relative
for R_PPC64_GOT_PCREL34. Implement R_PPC64_PCREL_OPT optimisation.
ld/
* testsuite/ld-powerpc/pcrelopt.s,
* testsuite/ld-powerpc/pcrelopt.d,
* testsuite/ld-powerpc/pcrelopt.sec: New test.
* testsuite/ld-powerpc/powerpc.exp: Run it.
When an instruction has operands, the PowerPC disassembler prints
spaces after the opcode so as to line up operands. If the operands
are all optional and all default value, then no operands are printed,
leaving trailing spaces. This patch fixes that.
opcodes/
* ppc-dis.c (print_insn_powerpc): Delay printing spaces after
opcode until first operand is output.
gas/
* testsuite/gas/ppc/476.d: Remove trailing spaces.
* testsuite/gas/ppc/a2.d: Likewise.
* testsuite/gas/ppc/booke.d: Likewise.
* testsuite/gas/ppc/booke_xcoff.d: Likewise.
* testsuite/gas/ppc/e500.d: Likewise.
* testsuite/gas/ppc/e500mc.d: Likewise.
* testsuite/gas/ppc/e6500.d: Likewise.
* testsuite/gas/ppc/htm.d: Likewise.
* testsuite/gas/ppc/power6.d: Likewise.
* testsuite/gas/ppc/power8.d: Likewise.
* testsuite/gas/ppc/power9.d: Likewise.
* testsuite/gas/ppc/vle.d: Likewise.
ld/
* testsuite/ld-powerpc/tlsexe32.d: Remove trailing spaces.
* testsuite/ld-powerpc/tlsopt5.d: Likewise.
* testsuite/ld-powerpc/tlsopt5_32.d: Likewise.
The syntax we ended up with for -m32 -fPIC calls to __tls_get_addr is
rather weird.
bl __tls_get_addr+0x8000(gd0@tlsgd)@plt
This came about by accident, probably due to requiring the arg reloc
before the call reloc.
Of course the @plt really belongs with __tls_get_addr since it affects
the call rather than the call arg, and it isn't a great deal of
trouble to ensure the relocs are emitted in the correct order. This
patch supports a newer syntax, like so:
bl __tls_get_addr+0x8000@plt(gd0@tlsgd)
gas/
* config/tc-ppc.c (parse_tls_arg): New function, extracted..
(md_assembler): ..from here. Call it after parsing other
suffix modifiers too.
ld/
* testsuite/ld-powerpc/tls32.s: Test new @plt syntax.
IFUNC resolvers must always be called via their global entry point.
They will be called from ld.so rather than from the local executable.
PR 23937
bfd/
* elf64-ppc.c (write_plt_relocs_for_local_syms): Don't add local
entry offset for ifuncs.
ld/
* testsuite/ld-powerpc/pr23937.d,
* testsuite/ld-powerpc/pr23937.s: New test.
* testsuite/ld-powerpc/powerpc.exp: Run it.
This patch, along with previous patches in the series, supports
putting the ELF file header and program headers in a PT_LOAD without
sections.
Logic governing whether headers a loaded has changed a little: The
primary reason to include headers is now the presence of
SIZEOF_HEADERS in a linker script. However, to support scripts that
may have reserved space for headers by hand, we continue to add
headers whenever the first section address is past the end of headers
modulo page size.
include/
* bfdlink.h (struct bfd_link_info): Add load_phdrs field.
bfd/
* elf-nacl.c (nacl_modify_segment_map): Cope with header PT_LOAD
lacking sections.
* elf.c (_bfd_elf_map_sections_to_segments): Assume file and
program headers are required when info->load_phdrs. Reorganize
code handling program headers. Generate a mapping without
sections just for file and program headers when -z separate-code
would indicate they should be on a different page to the first
section.
ld/
* ldexp.c (fold_name <SIZEOF_HEADERS>): Set link_info.load_phdrs.
* testsuite/ld-elf/loadaddr1.d: Pass -z noseparate-code.
* testsuite/ld-elf/loadaddr2.d: Likewise.
* testsuite/ld-i386/vxworks2.sd: Adjust expected output.
* testsuite/ld-powerpc/vxworks2.sd: Likewise.
* testsuite/ld-elf/overlay.d: Remove spu xfail.
* testsuite/ld-spu/ovl.lnk: Don't use SIZEOF_HEADERS.
* testsuite/ld-tic6x/dsbt-be.ld: Likewise.
* testsuite/ld-tic6x/dsbt-inrange.ld: Likewise.
* testsuite/ld-tic6x/dsbt-overflow.ld: Likewise.
* testsuite/ld-tic6x/dsbt.ld: Likewise.
This patch generates EH info for the new _notoc linkage stubs, to
support unwinding from asynchronous signal handlers. Unwinding
through the __tls_get_addr_opt stub was already supported, but that
was just a single stub. With multiple stubs the EH opcodes need to be
emitted and sized when iterating over stubs, so this is done when
emitting and sizing the stub code. Emitting the CIEs and FDEs is done
when sizing the stubs, as we did before in order to have the linker
generated FDEs indexed in .eh_frame_hdr. I moved the final tweaks to
FDEs from ppc64_elf_finish_dynamic_sections to ppc64_elf_build_stubs
simply because it's tidier to be done with them at that point.
bfd/
* elf64-ppc.c (struct map_stub): Delete tls_get_addr_opt_bctrl.
Add lr_restore, eh_size and eh_base.
(eh_advance, eh_advance_size): New functions.
(build_tls_get_addr_stub): Emit EH info for stub.
(ppc_build_one_stub): Likewise for _notoc stubs.
(ppc_size_one_stub): Size EH info for stub.
(group_sections): Init new map_stub fields.
(stub_eh_frame_size): Delete.
(ppc64_elf_size_stubs): Size EH info for stubs. Set up dummy EH
program for stubs.
(ppc64_elf_build_stubs): Reinit new map_stub fields. Set FDE
offset to stub section here..
(ppc64_elf_finish_dynamic_sections): ..rather than here.
ld/
* testsuite/ld-powerpc/notoc.s: Generate some cfi.
* testsuite/ld-powerpc/notoc.d: Adjust.
* testsuite/ld-powerpc/notoc.wf: New file.
* testsuite/ld-powerpc/powerpc.exp: Run "ext" and "notoc" tests
as run_ld_link_tests rather than run_dump_test.
R_PPC64_REL24_NOTOC is used on calls like "bl foo@notoc" to tell the
linker that linkage stubs for PLT calls or long branches can't use r2
for pic addressing. Instead, new stubs that generate pc-relative
addresses are used. One complication is that pc-relative offsets to
the PLT may need to be 64-bit in large programs, in contrast to the
toc-relative addressing used by older PLT linkage stubs where a 32-bit
offset is sufficient until the PLT itself exceeds 2G in size.
.eh_frame info to cover the _notoc stubs is yet to be implemented.
bfd/
* elf64-ppc.c (ADDI_R12_R11, ADDI_R12_R12, LIS_R12),
(ADDIS_R12_R11, ORIS_R12_R12_0, ORI_R12_R12_0),
(SLDI_R12_R12_32, LDX_R12_R11_R12, ADD_R12_R11_R12): Define.
(ppc64_elf_howto_raw): Add R_PPC64_REL24_NOTOC entry.
(ppc64_elf_reloc_type_lookup): Support R_PPC64_REL24_NOTOC.
(ppc_stub_type): Add ppc_stub_long_branch_notoc,
ppc_stub_long_branch_both, ppc_stub_plt_branch_notoc,
ppc_stub_plt_branch_both, ppc_stub_plt_call_notoc, and
ppc_stub_plt_call_both.
(is_branch_reloc): Add R_PPC64_REL24_NOTOC.
(build_offset, size_offset): New functions.
(plt_stub_size): Support plt_call_notoc and plt_call_both.
(ppc_build_one_stub, ppc_size_one_stub): Support new stubs.
(toc_adjusting_stub_needed): Handle R_PPC64_REL24_NOTOC.
(ppc64_elf_size_stubs): Likewise, and new stubs.
(ppc64_elf_build_stubs, ppc64_elf_relocate_section): Likewise.
* reloc.c: Add BFD_RELOC_PPC64_REL24_NOTOC.
* bfd-in2.h: Regenerate.
* libbfd.h: Regenerate.
gas/
* config/tc-ppc.c (ppc_elf_suffix): Support @notoc.
(ppc_force_relocation, ppc_fix_adjustable): Handle REL24_NOTOC.
ld/
* testsuite/ld-powerpc/ext.d,
* testsuite/ld-powerpc/ext.s,
* testsuite/ld-powerpc/ext.lnk,
* testsuite/ld-powerpc/notoc.d,
* testsuite/ld-powerpc/notoc.s: New tests.
* testsuite/ld-powerpc/powerpc.exp: Run them.
Not a lot is conveyed by putting _r2off in a stub symbol that can't be
seen by inspecting the stub code or the toc restoring instruction
immediately after a call via such a stub. Also, we don't distinguish
plt_call stub symbols from plt_call_r2save stub symbols, so this patch
makes long branch and plt branch stub symbols consistent with that
decision.
bfd/
* elf64-ppc.c (ppc_build_one_stub): Lose "_r2off" in stub symbols.
ld/
* testsuite/ld-powerpc/elfv2exe.d: Adjust for stub symbol change.
* testsuite/ld-powerpc/tocopt6.d: Likewise.
The modified test failed on some powerpc targets due to differences in
default hash style. If the default hash style is both, then more
sections are created, bumping section ids. Section id is used in stub
symbols and although the test is careful to not depend on id in
labels, the stub hash traversal order changes when stub names change.
That lead to the stubs being emitted in a different order and thus not
matching expected output.
* testsuite/ld-powerpc/powerpc.exp: Run tlsopt5 with hash-style
specified.
This patch sets stub_offset in ppc_size_one_stub rather than in
ppc_build_one_stub. That allows the plt stub alignment to be done in
just ppc_size_one_stub rather than both functions. The patch also
corrects the place where the alignment was done, fixing a possible
error in .eh_frame data, and tidies some offset calculations.
bfd/
* elf64-ppc.c (plt_stub_pad): Delay plt_stub_size call until needed.
(ppc_build_one_stub): Don't set stub_offset, instead assert that
it is sane. Don't adjust stub_offset for alignment. Adjust size
calculation. Use "targ" temp when calculating offsets.
(ppc_size_one_stub): Set stub_offset here. Use "targ" temp when
calculating offsets. Adjust for alignment before setting
tls_get_addr_opt_bctrl.
ld/
* testsuite/ld-powerpc/powerpc.exp: Run tlsopt5 with plt alignment.
* testsuite/ld-powerpc/tlsopt5.s: Add extra call.
* testsuite/ld-powerpc/tlsopt5.wf: Adjust expected output.
* testsuite/ld-powerpc/tlsopt5.d: Likewise.
This adds support for ".localentry 1", a new st_other
STO_PPC64_LOCAL_MASK encoding that signifies a function with a single
entry point like ".localentry 0", but unlike a ".localentry 0"
function does not preserve r2.
include/
* elf/ppc64.h: Specify byte offset to local entry for values
of two to six in STO_PPC64_LOCAL_MASK. Clarify r2 return
value for such functions when entering via global entry point.
Specify meaning of a value of one in STO_PPC64_LOCAL_MASK.
bfd/
* elf64-ppc.c (ppc64_elf_size_stubs): Use a ppc_stub_long_branch_r2off
for calls to symbols with STO_PPC64_LOCAL_MASK bits set to 1.
gas/
* config/tc-ppc.c (ppc_elf_localentry): Allow .localentry values
of 1 and 7 to directly set value into STO_PPC64_LOCAL_MASK bits.
ld/testsuite/
* ld-powerpc/elfv2.s: Add .localentry f5,1 testcase.
* ld-powerpc/elfv2exe.d: Update.
* ld-powerpc/elfv2so.d: Update.
One of the ill effects of ld -r is to mash together sections. That
can result in reduced icache performance at runtime due to unexpected
movement of code. Another problem is that sections can become too
large to link on targets that have limited relative addressing. ld -r
--relax attempts to overcome the large section problem for branches by
inserting trampolines, but the powerpc support added lots of
unnecessary trampolines. This patch trims them somewhat.
bfd/
* elf32-ppc.c (ppc_elf_relax_section): Ignore common or undef locals.
Avoid trashing toff with added when used as a symbol index.
Ignore R_PPC_PLTREL24 addends in unused example code. Avoid
creating unnecessary fixups when relocatable.
ld/
* testsuite/ld-powerpc/big.s: New file.
* testsuite/ld-powerpc/relaxrl.d: New test.
* testsuite/ld-powerpc/powerpc.exp: Run new test.
* testsuite/ld-powerpc/relaxr.d: Adjust.
And report the two input files that are incompatible rather than
reporting that an input file is incompatible with the output.
bfd/
* elf-bfd.h (_bfd_elf_ppc_merge_fp_attributes): Update prototype.
* elf32-ppc.c (_bfd_elf_ppc_merge_fp_attributes): Return error
on mismatch. Remove "warning: " from messages. Track last bfd
used to set tags.
(ppc_elf_merge_obj_attributes): Likewise. Handle status from
_bfd_elf_ppc_merge_fp_attributes.
* elf64-ppc.c (ppc64_elf_merge_private_bfd_data): Handle status
from _bfd_elf_ppc_merge_fp_attributes.
ld/
* testsuite/ld-powerpc/attr-gnu-4-12.d: Update expected output.
* testsuite/ld-powerpc/attr-gnu-4-13.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-21.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-23.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-31.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-32.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-8-23.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-12-21.d: Likewise.
max-page-size only matters for demand paged executables or shared
libraries, and the ideal size is the largest value used by your
operating system. Values larger than necessary just waste file space
and memory. common-page-size also affects file and memory size,
trading a possible small increase in file size for a decrease in
memory size when the operating system is using a common-page-size
page. With a powerpc max-page-size of 64k and common-page-size of 4k
many executables will use no more memory pages when the system page
size is 4k than an executable linked with -z max-page-size=0x1000,
yet will still run on a system using 64k pages. However, when running
on a system using 64k pages relro protection will not be completely
effective.
Due to the relro problem, powerpc binutils has been using a default
common-page-size of 64k since 2014-12-18 (git commit 04c6a44c7),
leading to complaints about increased file and memory sizes. People
not using relro do have a valid reason to complain..
So this patch introduces an extra back-end value to use as the default
for common-page-size when generating relro executables, and enables
the support for powerpc. Non relro executables will now be generated
with a default common-page-size of 4k.
bfd/
* elf-bfd.h (struct elf_backend_data): Add relropagesize.
* elfxx-target.h (ELF_RELROPAGESIZE): Provide default and
sanity test.
(elfNN_bed): Init relropagesize.
* bfd.c (bfd_emul_get_commonpagesize): Add boolean param to
select relropagesize.
* elf32-ppc.c (ELF_COMMONPAGESIZE): Define as 0x1000.
(ELF_RELROPAGESIZE): Define as ELF_MAXPAGESIZE.
(ELF_MINPAGESIZE): Don't define.
* elf64-ppc.c (ELF_COMMONPAGESIZE): Define as 0x1000.
(ELF_RELROPAGESIZE): Define as ELF_MAXPAGESIZE.
* bfd-in2.h: Regenerate.
ld/
* ldmain.c (main): Move config.maxpagesize and
config.commonpagesize initialization to..
* ldemul.c (after_parse_default): ..here.
* testsuite/ld-powerpc/ppc476-shared.d: Pass -z common-page-size.
* testsuite/ld-powerpc/ppc476-shared2.d: 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 GNU coding standard says error messages should be of the form
program:sourcefile:lineno: message
or
program: message
and
"The string message should not begin with a capital letter when it
follows a program name and/or file name, because that isn’t the
beginning of a sentence. (The sentence conceptually starts at the
beginning of the line.) Also, it should not end with a period."
This patch does that for ppc, and removes some British spelling.
I've also switched some error output from using the linker callback
einfo to _bfd_error_handler, due to improved compilation time
argument checking now done for the latter function.
bfd/
* elf32-ppc.c: Standardize error/warning messages. Use
_bfd_error_handler rather than einfo when einfo features not used.
* elf64-ppc.c: Likewise.
ld/
* testsuite/ld-powerpc/attr-gnu-12-21.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-12.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-13.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-21.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-23.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-31.d: Update.
* testsuite/ld-powerpc/attr-gnu-4-32.d: Update.
* testsuite/ld-powerpc/attr-gnu-8-23.d: Update.
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.
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.
It was reasonable to mark PT_PHDR segment with PF_X for compatibility
with UnixWare and Solaris linkers 20 years ago. But it is inappropriate
today when the primary OS of GNU ld is Linux. This patch removes PF_X
from PT_PHDR segment as gold does.
Tested natively on Linux/x86 as well as crosss-binutils for alpha-linux,
ia64-linux, powerpc64-linux, powerpc-linux, s390-linux, s390x-linux,
sparc64-linux and sparc-linux.
bfd/
PR ld/22423
* elf.c (_bfd_elf_map_sections_to_segments): Remove PF_X from
PT_PHDR segment.
ld/
PR ld/22423
* testsuite/ld-alpha/tlsbin.rd: Replace "R E " with "R +" for
PT_PHDR segment.
* testsuite/ld-alpha/tlsbinr.rd: Likewise.
* testsuite/ld-ia64/tlsbin.rd: Likewise.
* testsuite/ld-powerpc/tlsexe.r: Likewise.
* testsuite/ld-powerpc/tlsexe32.r: Likewise.
* testsuite/ld-powerpc/tlsexetoc.r: Likewise.
* testsuite/ld-s390/tlsbin.rd: Likewise.
* testsuite/ld-s390/tlsbin_64.rd: Likewise.
* testsuite/ld-sparc/tlssunbin32.rd: Likewise.
* testsuite/ld-sparc/tlssunbin64.rd: Likewise.
* testsuite/ld-elf/pr22423.d: New test.
We don't need a PLT entry when function pointer initialization in a
read/write section is the only reference to a given function symbol.
This patch prevents the unnecessary PLT entry, and ensures no dynamic
relocs are emitted when UNDEFWEAK_NO_DYNAMIC_RELOC says so.
bfd/
PR 22374
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Don't create a plt
entry when just a dynamic reloc can serve. Ensure no dynamic
relocations when UNDEFWEAK_NO_DYNAMIC_RELOC by setting non_got_ref.
Expand and move the non_got_ref comment.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol): Likewise.
ld/
* testsuite/ld-powerpc/ambiguousv2.d: Remove FIXME.
PowerPC64 .cfi directives use DW_EH_PE_sdata4 encoding for .eh_frame,
so there is no real reason why .eh_frame should be 8 byte aligned.
gas/
* config/tc-ppc.h (EH_FRAME_ALIGNMENT): Define.
ld/
* testsuite/ld-powerpc/tlsopt5.wf: Update for reduced alignment.
This changes the PowerPC64 --plt-align option to perform the usual
alignment of code as suggested by its name, as well as the previous
behaviour of padding so as to reduce boundary crossing. The old
behaviour is had by using a negative parameter.
The default is also changed to align plt stub code by default to 32
byte boundaries, the point being to get better bctr branch prediction
on power8 and power9 hardware.
bfd/
* elf64-ppp.c (plt_stub_pad): Handle positive and negative
plt_stub_align.
ld/
* ld.texinfo (--plt-align): Describe new behaviour of option.
* emultempl/ppc64elf.em (params): Default plt_stub_align to 5.
* testsuite/ld-powerpc/powerpc.exp: Pass --no-plt-align for
selected tests.
* testsuite/ld-powerpc/relbrlt.d: Pass --no-plt-align.
* testsuite/ld-powerpc/elfv2so.d: Adjust expected output.
In the TLS GD/LD to LE optimization, ld replaces a sequence like
addi 3,2,x@got@tlsgd R_PPC64_GOT_TLSGD16 x
bl __tls_get_addr(x@tlsgd) R_PPC64_TLSGD x
R_PPC64_REL24 __tls_get_addr
nop
with
addis 3,13,x@tprel@ha R_PPC64_TPREL16_HA x
addi 3,3,x@tprel@l R_PPC64_TPREL16_LO x
nop
When the tprel offset is small, this can be further optimized to
nop
addi 3,13,x@tprel
nop
bfd/
* elf64-ppc.c (struct ppc_link_hash_table): Add do_tls_opt.
(ppc64_elf_tls_optimize): Set it.
(ppc64_elf_relocate_section): Nop addis on TPREL16_HA, and convert
insn on TPREL16_LO and TPREL16_LO_DS relocs to use r13 when
addis would add zero.
* elf32-ppc.c (struct ppc_elf_link_hash_table): Add do_tls_opt.
(ppc_elf_tls_optimize): Set it.
(ppc_elf_relocate_section): Nop addis on TPREL16_HA, and convert
insn on TPREL16_LO relocs to use r2 when addis would add zero.
gold/
* powerpc.cc (Target_powerpc::Relocate::relocate): Nop addis on
TPREL16_HA, and convert insn on TPREL16_LO and TPREL16_LO_DS
relocs to use r2/r13 when addis would add zero.
ld/
* testsuite/ld-powerpc/tls.s: Add calls with tls markers.
* testsuite/ld-powerpc/tls32.s: Likewise.
* testsuite/ld-powerpc/powerpc.exp: Run tls marker tests.
* testsuite/ld-powerpc/tls.d: Adjust for TPREL16_HA/LO optimization.
* testsuite/ld-powerpc/tlsexe.d: Likewise.
* testsuite/ld-powerpc/tlsexetoc.d: Likewise.
* testsuite/ld-powerpc/tlsld.d: Likewise.
* testsuite/ld-powerpc/tlsmark.d: Likewise.
* testsuite/ld-powerpc/tlsopt4.d: Likewise.
* testsuite/ld-powerpc/tlstoc.d: Likewise.
There isn't a good reason for ld.bfd to behave differently from gold
in the code generated by TLS GD/LD to LE optimization.
bfd/
* elf64-ppc.c (ppc64_elf_relocate_section): When optimizing
__tls_get_addr call sequences to LE, don't move the addi down
to the nop. Replace the bl with addi and leave the nop alone.
ld/
* testsuite/ld-powerpc/tls.d: Update.
* testsuite/ld-powerpc/tlsexe.d: Update.
* testsuite/ld-powerpc/tlsexetoc.d: Update.
* testsuite/ld-powerpc/tlsld.d: Update.
* testsuite/ld-powerpc/tlsmark.d: Update.
* testsuite/ld-powerpc/tlsopt4.d: Update.
* testsuite/ld-powerpc/tlstoc.d: Update.
Since the __tls_get_addr_opt stub saves LR and makes a call, eh_frame
info should be generated to describe how to unwind through the stub.
The patch also changes the way the backend iterates over stubs, from
looking at all sections in stub_bfd to which all dynamic sections are
attached as well, to iterating over the group list, which gets just
the stub sections. Most binaries will have just one or two stub
groups, so this is a little faster.
bfd/
* elf64-ppc.c (struct map_stub): Add tls_get_addr_opt_bctrl.
(stub_eh_frame_size): New function.
(ppc_size_one_stub): Set group tls_get_addr_opt_bctrl.
(group_sections): Init group tls_get_addr_opt_bctrl.
(ppc64_elf_size_stubs): Update sizing and initialization of
.eh_frame. Iteration over stubs via group list.
(ppc64_elf_build_stubs): Iterate over stubs via group list.
(ppc64_elf_finish_dynamic_sections): Update finalization of
.eh_frame.
ld/
* testsuite/ld-powerpc/tlsopt5.s: Add cfi.
* testsuite/ld-powerpc/tlsopt5.d: Update.
* testsuite/ld-powerpc/tlsopt5.wf: New file.
* testsuite/ld-powerpc/powerpc.exp: Perform new tlsopt5 test.
These all were odd in that they used r13 as the GOT pointer. That
didn't matter for the purpose of testing, but would never occur in
practice. Also, the tlsopt5 tests could have their global dynamic
sequences optimized to initial exec, so link with -shared.
* testsuite/ld-powerpc/powerpc.exp: Add -shared to tlsop5 tests.
* testsuite/ld-powerpc/tlsopt5.d: Adjust.
* testsuite/ld-powerpc/tlsopt1_32.s: Use r30 as GOT pointer.
* testsuite/ld-powerpc/tlsopt2_32.s: Likewise.
* testsuite/ld-powerpc/tlsopt3_32.s: Likewise.
* testsuite/ld-powerpc/tlsopt4_32.s: Likewise.
* testsuite/ld-powerpc/tlsopt5_32.s: Rewrite.
* testsuite/ld-powerpc/tlsopt1_32.d: Adjust.
* testsuite/ld-powerpc/tlsopt2_32.d: Adjust.
* testsuite/ld-powerpc/tlsopt3_32.d: Adjust.
* testsuite/ld-powerpc/tlsopt5_32.d: Adjust.
Alan Modra
H.J. Lu
Nick Clifton