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.
This came up because I was looking at ld/tmpdir/addpcis.o and noticed
the odd addends on REL16DX_HA. They ought to both be -4. The error
crept in due REL16DX_HA howto being pc-relative (as indeed it should
be), and code at gas/write.c:1001 after this comment
/* Make it pc-relative. If the back-end code has not
selected a pc-relative reloc, cancel the adjustment
we do later on all pc-relative relocs. */
*not* cancelling the pc-relative adjustment. So I've made a dummy
non-relative split reloc so that the generic code handles this, rather
than attempting to add hacks later in md_apply_fix which would not be
very robust. Having the new internal reloc also makes it easy to
support
addpcis rx,sym@ha
as an equivalent to
addpcis rx,(sym-0f)@ha
0:
The patch also fixes overflow checking, which must test whether the
addi will overflow too since @l relocs don't have any overflow check.
Lastly, since I was poking at md_apply_fix, I arranged to have the
generic gas/write.c code emit errors for subtraction expressions where
we lack reloc support.
include/
* elf/ppc64.h (R_PPC64_16DX_HA): New. Expand fake reloc comment.
* elf/ppc.h (R_PPC_16DX_HA): Likewise.
bfd/
* reloc.c (BFD_RELOC_PPC_16DX_HA): New.
* elf64-ppc.c (ppc64_elf_howto_raw <R_PPC64_16DX_HA>): New howto.
(ppc64_elf_reloc_type_lookup): Translate new bfd reloc.
(ppc64_elf_ha_reloc): Correct overflow test on REL16DX_HA.
(ppc64_elf_relocate_section): Likewise.
* elf32-ppc.c (ppc_elf_howto_raw <R_PPC_16DX_HA>): New howto.
(ppc_elf_reloc_type_lookup): Translate new bfd reloc.
(ppc_elf_check_relocs): Handle R_PPC_16DX_HA to pacify gcc.
* libbfd.h: Regenerate.
* bfd-in2.h: Regenerate.
gas/
* config/tc-ppc.c (md_assemble): Use BFD_RELOC_PPC_16DX_HA for addpcis.
(md_apply_fix): Remove fx_subsy check. Move code converting to
pcrel reloc earlier and handle BFD_RELOC_PPC_16DX_HA. Remove code
emiiting errors on seeing fx_pcrel set on unexpected relocs, as
that is done now by the generic code via..
* config/tc-ppc.h (TC_FORCE_RELOCATION_SUB_LOCAL): ..this. Define.
(TC_VALIDATE_FIX_SUB): Define.
ld/
* testsuite/ld-powerpc/addpcis.d: Define ext1 and ext2 at
limits of addpcis range.
This patch extends Tag_GNU_Power_ABI_FP to cover long double ABIs,
makes the assembler warn about undefined tag values, and removes
similar warnings from the linker. I think it is better to not
warn in the linker about undefined tag values as future extensions to
the tags then won't result in likely bogus warnings. This is
consistent with the fact that an older linker won't warn on an
entirely new tag.
include/
* elf/ppc.h (Tag_GNU_Power_ABI_FP): Comment.
bfd/
* elf-bfd.h (_bfd_elf_ppc_merge_fp_attributes): Declare.
* elf32-ppc.c (_bfd_elf_ppc_merge_fp_attributes): New function.
(ppc_elf_merge_obj_attributes): Use it. Don't copy first file
attributes, merge them. Don't warn about undefined tag bits,
or copy unknown values to output.
* elf64-ppc.c (ppc64_elf_merge_private_bfd_data): Call
_bfd_elf_ppc_merge_fp_attributes.
binutils/
* readelf.c (display_power_gnu_attribute): Catch truncated section
for all powerpc attributes. Display long double ABI. Don't
capitalize words, except for names. Show known bits of tag values
when some unknown bits are present. Whitespace fixes.
gas/
* config/tc-ppc.c (ppc_elf_gnu_attribute): New function.
(md_pseudo_table <ELF>): Handle "gnu_attribute".
ld/
* testsuite/ld-powerpc/attr-gnu-4-4.s: Delete.
* testsuite/ld-powerpc/attr-gnu-4-14.d: Delete.
* testsuite/ld-powerpc/attr-gnu-4-24.d: Delete.
* testsuite/ld-powerpc/attr-gnu-4-34.d: Delete.
* testsuite/ld-powerpc/attr-gnu-4-41.d: Delete.
* testsuite/ld-powerpc/attr-gnu-4-32.d: Adjust expected warning.
* testsuite/ld-powerpc/attr-gnu-8-23.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-01.d: Adjust expected output.
* testsuite/ld-powerpc/attr-gnu-4-02.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-03.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-10.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-11.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-20.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-22.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-4-33.d: Likewise.
* testsuite/ld-powerpc/attr-gnu-8-11.d: Likewise.
* testsuite/ld-powerpc/powerpc.exp: Don't run deleted tests.
VLE is an encoding, not a particular processor architecture, so it
isn't really proper to select insns based on PPC_OPCODE_VLE. For
example
{"evaddw", VX (4, 512), VX_MASK, PPCSPE|PPCVLE, PPCNONE, {RS, RA, RB}},
{"vaddubs", VX (4, 512), VX_MASK, PPCVEC|PPCVLE, PPCNONE, {VD, VA, VB}},
shows two insns that have the same encoding, both available with VLE.
Enabling both with VLE means we can't disassemble the second variant
even if -Maltivec is given rather than -Mspe. Also, we don't check
user assembly against the processor type as well as we could.
Another problem is that when using the VLE encoding, insns from the
main ppc opcode table are not available, except those using opcode 4
and 31. Correcting this revealed two errors in the ld testsuite,
use of "nop" and "rfmci" when -mvle.
This patch fixes those problems in the opcode table, and removes
PPCNONE. I find a plain 0 distracts less from other values.
In addition, I've implemented code to recognize some machine values
from the apuinfo note present in ppc32 objects. It's not a complete
disambiguation since we're lacking info to detect newer chips, but
what we have should help with disassembly.
include/
* elf/ppc.h (APUINFO_SECTION_NAME, APUINFO_LABEL, PPC_APUINFO_ISEL,
PPC_APUINFO_PMR, PPC_APUINFO_RFMCI, PPC_APUINFO_CACHELCK,
PPC_APUINFO_SPE, PPC_APUINFO_EFS, PPC_APUINFO_BRLOCK,
PPC_APUINFO_VLE: Define.
opcodes/
* ppc-dis.c (ppc_opts): Delete extraneous parentheses. Default
cpu for "vle" to e500.
* ppc-opc.c (ALLOW8_SPRG): Remove PPC_OPCODE_VLE.
(NO371, PPCSPE, PPCISEL, PPCEFS, MULHW, DCBT_EO): Likewise.
(PPCNONE): Delete, substitute throughout.
(powerpc_opcodes): Remove PPCVLE from "flags". Add to "deprecated"
except for major opcode 4 and 31.
(vle_opcodes <se_rfmci>): Add PPCRFMCI to flags.
bfd/
* cpu-powerpc.c (powerpc_compatible): Allow bfd_mach_ppc_vle entry
to match other 32-bit archs.
* elf32-ppc.c (_bfd_elf_ppc_set_arch): New function.
(ppc_elf_object_p): Call it.
(ppc_elf_special_sections): Use APUINFO_SECTION_NAME. Fix
overlong line.
(APUINFO_SECTION_NAME, APUINFO_LABEL): Don't define here.
* elf64-ppc.c (ppc64_elf_object_p): Call _bfd_elf_ppc_set_arch.
* bfd-in.h (_bfd_elf_ppc_at_tls_transform,
_bfd_elf_ppc_at_tprel_transform): Move to..
* elf-bfd.h: ..here.
(_bfd_elf_ppc_set_arch): Declare.
* bfd-in2.h: Regenerate.
gas/
* config/tc-ppc.c (PPC_APUINFO_ISEL, PPC_APUINFO_PMR,
PPC_APUINFO_RFMCI, PPC_APUINFO_CACHELCK, PPC_APUINFO_SPE,
PPC_APUINFO_EFS, PPC_APUINFO_BRLOCK, PPC_APUINFO_VLE): Don't define.
(ppc_setup_opcodes): Check vle disables powerpc_opcodes overridden
by vle_opcodes, and that vle flag doesn't enable opcodes. Don't
add vle_opcodes twice.
(ppc_cleanup): Use APUINFO_SECTION_NAME and APUINFO_LABEL.
ld/
* testsuite/ld-powerpc/apuinfo1.s: Delete nop.
* testsuite/ld-powerpc/apuinfo-vle2.s: New.
* testsuite/ld-powerpc/powerpc.exp: Use apuinfo-vle2.s.
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.
include/elf/
* ppc.h (R_PPC_RELAX32, R_PPC_RELAX32PC, R_PPC_RELAX32_PLT,
R_PPC_RELAX32PC_PLT): Delete.
(R_PPC_RELAX, R_PPC_RELAX_PLT, R_PPC_RELAX_PLTREL24): Define.
bfd/
* elf32-ppc.c (update_plt_info): Clear sec here when addend is
less than 32768..
(ppc_elf_check_relocs): ..rather than doing so here. Ignore new
relax relocs.
(ppc_elf_gc_sweep_hook): Don't segfault when symbol hiding has
removed plt_entry records.
(ppc_elf_tls_setup): Handle PIE calls to __tls_get_addr correctly.
(ppc_elf_tls_optimize): Likewise. Also dec __tls_get_addr refcount
when optimizing code using new tlsgd and tlsld marker relocs.
(ppc_elf_relax_section): Differentiate relaxed PLTREL24 relocs
from ADDR24 relocs using plt or glink. Don't clear the addend
for R_PPC_RELAX_PLTREL24.
(ppc_elf_relocate_section): Correctly handle addends on relaxed
PLTREL24 relocs.
* ppc.h (R_PPC_TLSGD, R_PPC_TLSLD): Add new relocs.
* ppc64.h (R_PPC64_TLSGD, R_PPC64_TLSLD): Add new relocs.
bfd/
* reloc.c (BFD_RELOC_PPC_TLSGD, BFD_RELOC_PPC_TLSLD): New.
* section.c (struct bfd_section): Add has_tls_get_addr_call.
(BFD_FAKE_SECTION): Init new flag.
* ecoff.c (bfd_debug_section): Likewise.
* bfd-in2.h: Regenerate.
* libbfd.h: Regenerate.
* elf32-ppc.c (ppc_elf_howto_raw): Add R_PPC_TLSGD and R_PPC_TLSLD.
(ppc_elf_reloc_type_lookup): Handle new relocs.
(ppc_elf_check_relocs): Set has_tls_get_addr_call on finding such
without marker relocs.
(ppc_elf_tls_optimize): Allow out-of-order __tls_get_addr relocs
if section has no old-style calls.
(ppc_elf_relocate_section): Set tls_mask for non-tls relocs too.
Don't try to optimize new-style __tls_get_addr call when handling
arg setup relocs. Instead do so for R_PPC_TLSGD and R_PPC_TLSLD
relocs.
* elf64-ppc.c (ppc64_elf_howto_raw): Add R_PPC64_TLSGD, R_PPC64_TLSLD.
(ppc64_elf_reloc_type_lookup): Handle new relocs.
(ppc64_elf_check_relocs): Set has_tls_get_addr_call on finding such
without marker relocs.
(ppc64_elf_tls_optimize): Allow out-of-order __tls_get_addr relocs
if section has no old-style calls. Set toc_ref for new relocs as
appropriate.
(ppc64_elf_relocate_section): Set tls_mask for non-tls relocs too.
Don't try to optimize new-style __tls_get_addr call when handling
arg setup relocs. Instead do so for R_PPC_TLSGD and R_PPC_TLSLD
relocs.
gas/
* config/tc-ppc.c (ppc_elf_suffix): Error if ppc32 tls got relocs
have non-zero addend.
(md_assemble): Parse args of __tls_get_addr calls.
(md_apply_fix): Handle BFD_RELOC_PPC_TLSGD and BFD_RELOC_PPC_TLSLD.
ld/testsuite/
* ld-powerpc/tlsmark.s, * ld-powerpc/tlsmark.d: New test.
* ld-powerpc/tlsmark32.s, * ld-powerpc/tlsmark32.d: New test.
* ld-powerpc/powerpc.exp: Run them.
* elf32-ppc.c (R_PPC_RELAX32): New relocation.
(ppc_elf_install_value): New function.
(ppc_elf_sort_rela): Remove.
(ppc_elf_relax_section): Rewrite. Remove old relaxation
and replace with out of range branch stubs.
(ppc_elf_relocate_section): Handle R_PPC_RELAX32.
2003-07-28 Eric Christopher <echristo@redhat.com>
* ppc.h (R_PPC_RELAX32): New. Fake relocation.
