We have an issue in the MIPS backend, with the handling of undefined
hidden and internal weak symbols. References to such symbols are
supposed to resolve to 0 according to the ELF gABI[1]:
"Unresolved weak symbols have a zero value."
and the 64-bit MIPS psABI[2]:
"If a symbol with one of these [hidden or internal] attributes has no
definition within the executable/DSO being linked, then it must be
resolved to allocated space if common, resolved to zero if weak, or an
error reported otherwise."
however if a GOT relocation is used, then a local GOT entry is created
and used to satisfy the reference. Such an entry is then (in DSO and
PIE binaries) subject to the usual load-time relocation, which means a
non-zero value will be returned if the base address is non-zero. This
will defeat the usual run-time sequence like:
void a (void) __attribute__ ((visibility ("hidden"), weak));
void
x (void)
{
if (a)
a ();
}
This can be reproduced with this simple code:
$ cat libtest.c
extern int a __attribute__ ((visibility ("hidden"), weak));
int *
x (void)
{
return &a;
}
$ cat test.c
int *x (void);
int
main (void)
{
printf ("a: %p\n", x ());
return 0;
}
$ gcc -shared -fPIC -o libtest.so libtest.c
$ gcc -o test test.c -Wl,-rpath,$(pwd) libtest.so
$ ./test
a: 0x77184000
$
The usual approach targets take is making all the steps required to
assign a GOT entry for the symbol referred, and then leave its contents
at zero with no dynamic relocation attached, therefore ensuring that the
value does not change at load time. However this is not going to work
with the implicitly relocated GOT the MIPS psABI specifies[3]:
"The dynamic linker relocates the global offset table by first adding
the difference between the base where the shared object is loaded and
the value of the dynamic tag DT_MIPS_BASE_ADDRESS to all local global
offset table entries."
and we cannot therefore use the local GOT part.
And we cannot offhand use the global part either, as the symbol would
then have to be exported and possibly wrongly preempt symbols in other
modules involved in the dynamic load, because as per the ELF gABI[1] we
are not allowed to enter a hidden or internal symbol into the dynamic
symbol table (and then use its associated GOT entry):
"A hidden symbol contained in a relocatable object must be either
removed or converted to STB_LOCAL binding by the link-editor when the
relocatable object is included in an executable file or shared object."
and:
"An internal symbol contained in a relocatable object must be either
removed or converted to STB_LOCAL binding by the link-editor when the
relocatable object is included in an executable file or shared object."
So we have to choose something else.
Our choice is further limited by the need for the reference associated
with the GOT relocation to stay within the signed 16-bit limit from the
GOT pointer base register, while being compliant with the ELF gABI and
the MIPS psABI. However as Alan Modra has observed[4] one possibility
is to edit (relax) the code such that the GOT reference is removed
altogether.
Based on these observations then modify MIPS BFD linker backend code to:
1. Interpret code associated with GOT relocations and relax the usual LW
or LD instructions into a corresponding immediate load operation that
places the value of 0 in the intended register, while leaving the GOT
entry allocated and initialized as usually.
2. Leave any other instructions associated with GOT relocations in place
and instead redirect the reference to a global GOT entry associated
with a special `__gnu_absolute_zero' symbol created for this purpose,
whose value is 0, SHN_ABS section marks it absolute, binding is
global and export class protected, ensuring that the locally provided
value is always used at load time, and that the value is not
relocated by the dynamic loader.
3. Adjust any high-part GOT relocation used, typically associated with
a LUI instruction, accordingly, so that run-time consistency is
maintained, either by resolving to the original entry if the
instruction associated with the corresponding low-part GOT relocation
has been relaxed to an immediate load (in which case the value loaded
with LUI will be overwritten), or by also redirecting the reference
to `__gnu_absolute_zero' to complete the GOT access sequence if that
symbol has been used.
4. Add a target `elf_backend_hide_symbol' hook, for the three MIPS ABIs,
which prevents the `__gnu_absolute_zero' symbol from being forced
local, to ensure that the redirection works and the symbol remains
global/protected with existing linker scripts unchanged.
5. Observing the issue with handling SHN_ABS symbols in the GNU dynamic
loader, covered by glibc PR 19818, set the EI_ABIVERSION field in the
ELF file header produced to 4 (ABI_ABSOLUTE) if `__gnu_absolute_zero'
symbol has been produced and the target configured indicates the GNU
operating system, so that broken versions of the GNU dynamic loader
gracefully reject the file in loading rather than going astray. Keep
EI_ABIVERSION at the original value for other operating systems or if
no `__gnu_absolute_zero' symbol has been made.
The name of the special `__gnu_absolute_zero' has no meaning other than
how a human reader can interpret it, as it is ignored in dynamic loading
in the handling of the scenarios concerned. This is because the symbol
resolves locally, and it's only the symbol's attributes that matter so
that the associated GOT entry remains unchanged at load time.
Therefore the name is somewhat arbitrary, observing however the need to
use the name space reserved for the system so that it does not conflict
with a possible user symbol, and hence the leading underscore, and also
the `gnu' infix to denote a GNU feature. Other implementations wishing
to address the problem in a similar way may choose a different name and
have the solution still work, possibly with a mixture of modules used in
a dynamic having symbols of different names provided, which will however
not interact with each other due to the protected export class.
The symbol can be referred explicitly, however the name is an internal
implementation detail rather than a part of the ABI, and therefore no
specific semantics is guaranteed.
One limitation of this change is that if `__gnu_absolute_zero' has been
already defined, then we do not wipe the old definition and all kinds of
odd behavior can result. This is however like with other symbols we
internally define, such as `_GLOBAL_OFFSET_TABLE_' or `__rld_map', and
therefore left as a possible future enhancement.
As an optimization the relaxation of LW and LD instructions to a load of
immediate zero is always made, even SVR4 PIC code for code that will end
up in a regular (non-PIE) executable, because there is a cache advantage
with the avoidance of a load from the GOT, even if it is otherwise
guaranteed to remain zero. It does not reliably happen though, due to a
symbol exportation issue affecting executables, covered by PR ld/21805.
One existing test case needs to be updated, as it triggers relaxation
introduced with this change and consequently linker output does not
match expectations anymore. As we want to keep the original issue
covered with the test case modify it then to use the LWL instruction in
place of LW, and adjust the output expected accordingly.
References:
[1] "System V Application Binary Interface - DRAFT - 19 October 2010",
The SCO Group, Section "Symbol Table",
<http://www.sco.com/developers/gabi/2012-12-31/ch4.symtab.html>
[2] "64-bit ELF Object File Specification, Draft Version 2.5", MIPS
Technologies / Silicon Graphics Computer Systems, Order Number
007-4658-001, Section 2.5 "Symbol Table", p. 22,
<http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf>
[3] "SYSTEM V APPLICATION BINARY INTERFACE, MIPS RISC Processor
Supplement, 3rd Edition", Section "Global Offset Table", p. 5-10,
<http://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf>
[4] "Undo dynamic symbol state after regular object sym type mismatch",
<https://sourceware.org/ml/binutils/2017-07/msg00265.html>
bfd/
PR ld/21375
* elfxx-mips.h (_bfd_mips_elf_hide_symbol): New prototype.
(_bfd_mips_elf_linker_flags): Update prototype.
* elf32-mips.c (elf_backend_hide_symbol): New macro.
* elf64-mips.c (elf_backend_hide_symbol): Likewise.
* elfn32-mips.c (elf_backend_hide_symbol): Likewise.
* elfxx-mips.c (mips_elf_link_hash_table): Add
`use_absolute_zero' and `gnu_target' members.
(mips_elf_record_global_got_symbol): Call
`_bfd_mips_elf_hide_symbol' rather than
`_bfd_elf_link_hash_hide_symbol'.
(mips_use_local_got_p): Return FALSE if the symbol is absolute.
(mips_elf_obtain_contents): Reorder function.
(mips_elf_nullify_got_load): New function.
(mips_elf_calculate_relocation): Add `contents' parameter.
Nullify GOT loads or if it is not possible, then redirect GOT
relocations to the `__gnu_absolute_zero' symbol, for references
that are supposed to resolve to zero.
(mips_elf_define_absolute_zero): New function.
(_bfd_mips_elf_check_relocs): Prepare for arrangements made in
`mips_elf_calculate_relocation' for references made via the GOT
that are supposed to resolve to zero.
(_bfd_mips_elf_hide_symbol): New function.
(_bfd_mips_elf_linker_flags): Add the `gnu_target' parameter,
set the `gnu_target' member of the MIPS hash table.
(MIPS_LIBC_ABI_ABSOLUTE): New enumeration constant.
(_bfd_mips_post_process_headers): Use it.
ld/
PR ld/21375
* emultempl/mipself.em: Set `gnu_target' according to ${target}.
(mips_create_output_section_statements): Update call to
`_bfd_mips_elf_linker_flags'.
* testsuite/ld-mips-elf/pr21334.s: Use LWL rather than LW.
* testsuite/ld-mips-elf/pr21334.dd: Update accordingly.
The _gp_disp is a magic symbol, always implicitly defined by the linker.
It does not make a sense to write it into symbol tables for output files.
Moreover, now if the linker gets a version script, the _gp_disp symbol
gets zero version definition index. The zero index means[1]:
"The symbol is local, not available outside the object."
But the _gp_disp symbol has GLOBAL binding. That confuses some tools
like for example the LLD linker when they get such files as inputs.
This patch fixes the problem - it prevents writing the _gp_disp symbol
in regular and dynamic symbol tables.
This was tested by running LD test suite on a mipsel-linux board.
References:
[1] "Linux Standard Base Specification", Section "10.7.2 Symbol
Version Table", p. 32
2018-05-03 Simon Atanasyan <simon@atanasyan.com>
bfd/
* elf32-mips.c: (elf32_mips_fixup_symbol): New function.
(elf_backend_fixup_symbol): New macro.
* elfxx-mips.c: (mips_elf_output_extsym): Discard _gp_disp
handling.
(_bfd_mips_elf_finish_dynamic_symbol): Likewise.
ld/
* testsuite/ld-mips-elf/gp-disp-sym.d: New test.
* testsuite/ld-mips-elf/gp-disp-sym.s: New test source.
* testsuite/ld-mips-elf/mips-elf.exp: Run the new test.
* testsuite/ld-mips-elf/mips16-pic-2.ad: Update for _gp_disp
symbol removal.
* testsuite/ld-mips-elf/mips16-pic-2.nd: Likewise.
* testsuite/ld-mips-elf/pic-and-nonpic-3a.dd: Likewise.
* testsuite/ld-mips-elf/tlslib-o32-hidden.got: Likewise.
* testsuite/ld-mips-elf/tlslib-o32-ver.got: Likewise.
* testsuite/ld-mips-elf/tlslib-o32.got: Likewise.
Do not consider placeholder EMPTY_HOWTO relocation entries valid in
`rtype_to_howto' MIPS handlers. Instead issue an unsupported relocation
type error and return a NULL howto as with relocations outside the three
ISA-specific min-max ranges.
bfd/
* elf32-mips.c (mips_elf32_rtype_to_howto): Also return
unsuccessfully for placeholder howtos.
* elf64-mips.c (mips_elf64_rtype_to_howto): Likewise.
* elfn32-mips.c (mips_elf_n32_rtype_to_howto): Likewise.
Remove a duplicate `unsupported relocation type' message and the setting
of the `bfd_error_bad_value' error from `mips_elf32_rtype_to_howto',
added with commit f3185997ac ("PR 22875: Stop strip corrupting unknown
relocs"), <https://sourceware.org/ml/binutils/2018-02/msg00445.html>.
This message is already produced and the `bfd_error_bad_value' error set
by `mips_elf32_rtype_to_howto' before a NULL howto is returned, so there
is no need to repeat these actions here.
bfd/
* elf32-mips.c (mips_info_to_howto_rel): Remove the calls to
`_bfd_error_handler' and to set the `bfd_error_bad_value' error.
Call `mips_elf32_rtype_to_howto' directly rather than via the
`->elf_backend_mips_rtype_to_howto' method in the o32 backend,
complementing commit 861fb55ab5 ("Defer allocation of R_MIPS_REL32 GOT
slots"), <https://sourceware.org/ml/binutils/2008-08/msg00096.html>, and
reverting the change to `mips_info_to_howto_rel' originally made with
commit 0a44bf6950 ("mips-vxworks support"),
<https://sourceware.org/ml/binutils/2006-03/msg00179.html>.
With `mips_vxworks_rtype_to_howto' gone there is a single backend method
used across all o32 targets, so there in no need for the indirection and
the associated extra cost. This also makes the o32 backend consistent
with the n32 and n64 backends.
bfd/
* elf32-mips.c (mips_info_to_howto_rel): Call
`mips_elf32_rtype_to_howto' directly rather than via
`->elf_backend_mips_rtype_to_howto'.
On MIPS o32, n32 and n64 platforms, PID information was not
correctly propagated from core dump file to internal GDB
structures. This patch fixes that behavior.
A correct PID is needed by `libthread_db' library supplied with
glibc repository revisions before commit c579f48edba8 ("Remove
cached PID/TID in clone") or released versions before 2.25 for
GDB to fetch value of TLS variable from core file.
bfd/ChangeLog:
* elf32-mips.c (elf32_mips_grok_psinfo): Extract core->pid.
* elf64-mips.c (elf64_mips_grok_psinfo): Likewise.
* elfn32-mips.c (elf32_mips_grok_psinfo): Likewise.
On MIPS o32, n32 and n64 platforms information such as PID was not
correctly written into core file from GDB.
This fixes that behavior.
bfd/ChangeLog:
* elf32-mips.c (elf32_mips_write_core_note): New function.
(elf_backend_write_core_note): New macro.
* elf64-mips.c (elf64_mips_write_core_note): New function.
(elf_backend_write_core_note): New macro.
* elfn32-mips.c (elf32_mips_write_core_note): New function.
(elf_backend_write_core_note): New macro.
Variables defined in shared libraries are copied into an executable's
.bss section when code in the executable is non-PIC and thus would
require dynamic text relocations to access the variable directly in
the shared library. Recent x86 toolchains also copy variables into
the executable to gain a small speed improvement.
The problem is that if the variable was originally read-only, the copy
in .bss is writable, potentially opening a security hole. This patch
cures that problem by putting the copy in a section that becomes
read-only after ld.so relocation, provided -z relro is in force.
The patch also fixes a microblaze linker segfault on attempting to
use dynamic bss variables.
bfd/
PR ld/20995
* elf-bfd.h (struct elf_link_hash_table): Add sdynrelro and
sreldynrelro.
(struct elf_backend_data): Add want_dynrelro.
* elfxx-target.h (elf_backend_want_dynrelro): Define.
(elfNN_bed): Update initializer.
* elflink.c (_bfd_elf_create_dynamic_sections): Create
sdynrelro and sreldynrelro sections.
* elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Place variables
copied into the executable from read-only sections into sdynrelro.
(elf32_arm_size_dynamic_sections): Handle sdynrelro.
(elf32_arm_finish_dynamic_symbol): Select sreldynrelro for
dynamic relocs in sdynrelro.
(elf_backend_want_dynrelro): Define.
* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol)
(elf32_hppa_size_dynamic_sections, elf32_hppa_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-i386.c (elf_i386_adjust_dynamic_symbol)
(elf_i386_size_dynamic_sections, elf_i386_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-metag.c (elf_metag_adjust_dynamic_symbol)
(elf_metag_size_dynamic_sections, elf_metag_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol)
(microblaze_elf_size_dynamic_sections)
(microblaze_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol)
(nios2_elf32_adjust_dynamic_symbol)
(nios2_elf32_size_dynamic_sections)
(elf_backend_want_dynrelro): As above.
* elf32-or1k.c (or1k_elf_finish_dynamic_symbol)
(or1k_elf_adjust_dynamic_symbol, or1k_elf_size_dynamic_sections)
(elf_backend_want_dynrelro): As above.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol)
(ppc_elf_size_dynamic_sections, ppc_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-s390.c (elf_s390_adjust_dynamic_symbol)
(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol)
(elf32_tic6x_size_dynamic_sections)
(elf32_tic6x_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-tilepro.c (tilepro_elf_adjust_dynamic_symbol)
(tilepro_elf_size_dynamic_sections)
(tilepro_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol)
(ppc64_elf_size_dynamic_sections, ppc64_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-s390.c (elf_s390_adjust_dynamic_symbol)
(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-x86-64.c (elf_x86_64_adjust_dynamic_symbol)
(elf_x86_64_size_dynamic_sections)
(elf_x86_64_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol)
(elfNN_aarch64_size_dynamic_sections)
(elfNN_aarch64_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol)
(riscv_elf_size_dynamic_sections, riscv_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol)
(_bfd_mips_elf_size_dynamic_sections)
(_bfd_mips_vxworks_finish_dynamic_symbol): As above.
* elfxx-sparc.c (_bfd_sparc_elf_adjust_dynamic_symbol)
(_bfd_sparc_elf_size_dynamic_sections)
(_bfd_sparc_elf_finish_dynamic_symbol): As above.
* elfxx-tilegx.c (tilegx_elf_adjust_dynamic_symbol)
(tilegx_elf_size_dynamic_sections)
(tilegx_elf_finish_dynamic_symbol): As above.
* elf32-mips.c (elf_backend_want_dynrelro): Define.
* elf64-mips.c (elf_backend_want_dynrelro): Define.
* elf32-sparc.c (elf_backend_want_dynrelro): Define.
* elf64-sparc.c (elf_backend_want_dynrelro): Define.
* elf32-tilegx.c (elf_backend_want_dynrelro): Define.
* elf64-tilegx.c (elf_backend_want_dynrelro): Define.
* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Tidy.
(microblaze_elf_size_dynamic_sections): Handle sdynbss.
* elf32-nios2.c (nios2_elf32_size_dynamic_sections): Make use
of linker shortcuts to dynamic sections rather than comparing
names. Correctly set "got" flag.
ld/
PR ld/20995
* testsuite/ld-arm/farcall-mixed-app-v5.d: Update to suit changed
stub hash table traversal caused by section id increment. Accept
the previous output too.
* testsuite/ld-arm/farcall-mixed-app.d: Likewise.
* testsuite/ld-arm/farcall-mixed-lib-v4t.d: Likewise.
* testsuite/ld-arm/farcall-mixed-lib.d: Likewise.
* testsuite/ld-elf/pr20995a.s, * testsuite/ld-elf/pr20995b.s,
* testsuite/ld-elf/pr20995.r: New test.
* testsuite/ld-elf/elf.exp: Run it.
Complement:
commit b47468a6db
Author: Catherine Moore <clm@redhat.com>
Date: Mon May 6 15:25:45 2013 +0000
and the return of support for R_MIPS_PC32 there.
bfd/
* elf32-mips.c (elf_mips_gnu_pcrel32): Update comment.
HI16/LO16 are deliberately put adjacent, which might mean relocs are
then not sorted by r_offset. See tc-mips.c:mips_frob_file. Don't undo
the HI16/LO16 sorting.
PR 17666
* elf-bfd.h (struct elf_backend_data): Add sort_relocs_p.
* elfxx-target.h (elf_backend_sort_relocs_p): Define.
(elfNN_bed): Init new field.
* elflink.c (elf_link_adjust_relocs): Conditionally sort.
(bfd_elf_final_link): Control sorting of relocs.
* elfxx-mips.c (_bfd_mips_elf_sort_relocs_p): New function.
* elfxx-mips.h (_bfd_mips_elf_sort_relocs_p): Declare.
* elf32-mips.c (elf_backend_sort_relocs_p): Define.
* elf64-mips.c (elf_backend_sort_relocs_p): Define.
bfd/
* aoutx.h (NAME (aout, machine_type)): Add mips32r6 and mips64r6.
* archures.c (bfd_architecture): Likewise.
* bfd-in2.h (bfd_architecture): Likewise.
(bfd_reloc_code_real): Add relocs BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3 and
BFD_RELOC_MIPS_19_PCREL_S2.
* cpu-mips.c (arch_info_struct): Add mips32r6 and mips64r6.
* elf32-mips.c: Define relocs R_MIPS_PC21_S2, R_MIPS_PC26_S2
R_MIPS_PC18_S3, R_MIPS_PC19_S2, R_MIPS_PCHI16 and R_MIPS_PCLO16.
(mips_reloc_map): Add entries for BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3,
BFD_RELOC_MIPS_19_PCREL_S2, BFD_RELOC_HI16_S_PCREL and
BFD_RELOC_LO16_PCREL.
* elf64-mips.c: Define REL, and RELA relocations R_MIPS_PC21_S2,
R_MIPS_PC26_S2, R_MIPS_PC18_S3, R_MIPS_PC19_S2, R_MIPS_PCHI16
and R_MIPS_PCLO16.
(mips_reloc_map): Add entries for BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3,
BFD_RELOC_MIPS_19_PCREL_S2, BFD_RELOC_HI16_S_PCREL and
BFD_RELOC_LO16_PCREL.
* elfn32-mips.c: Likewise.
* elfxx-mips.c (MIPSR6_P): New define.
(mipsr6_exec_plt_entry): New array.
(hi16_reloc_p): Add support for R_MIPS_PCHI16.
(lo16_reloc_p): Add support for R_MIPS_PCLO16.
(aligned_pcrel_reloc_p): New function.
(mips_elf_relocation_needs_la25_stub): Add support for relocs:
R_MIPS_PC21_S2 and R_MIPS_PC26_S2.
(mips_elf_calculate_relocation): Add support for relocs:
R_MIPS_PC21_S2, R_MIPS_PC26_S2, R_MIPS_PC18_S3, R_MIPS_PC19_S2,
R_MIPS_PCHI16 and R_MIPS_PCLO16.
(_bfd_elf_mips_mach): Add support for mips32r6 and mips64r6.
(mips_elf_add_lo16_rel_addend): Add support for R_MIPS_PCHI16.
(_bfd_mips_elf_check_relocs): Add support for relocs:
R_MIPS_PC21_S2 and R_MIPS_PC26_S2.
(_bfd_mips_elf_relocate_section): Add a check for unaligned
pc relative relocs.
(_bfd_mips_elf_finish_dynamic_symbol): Add support for MIPS r6
plt entry.
(mips_set_isa_flags): Add support for mips32r6 and mips64r6.
(_bfd_mips_elf_print_private_bfd_data): Likewise.
(mips_32bit_flags_p): Add support for mips32r6.
* libbfd.h (bfd_reloc_code_real_names): Add entries for
BFD_RELOC_MIPS_21_PCREL_S2, BFD_RELOC_MIPS_26_PCREL_S2,
BFD_RELOC_MIPS_18_PCREL_S3 and BFD_RELOC_MIPS_19_PCREL_S2.
* reloc.c: Document relocs BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3 and
BFD_RELOC_MIPS_19_PCREL_S2.
binutils/
* readelf.c (get_machine_flags): Add support for mips32r6 and
mips64r6.
elfcpp/
* mips.h (E_MIPS_ARCH_32R6, E_MIPS_ARCH_64R6): New enum constants.
gas/
* config/tc-mips.c (mips_nan2008): New static global.
(mips_flag_nan2008): Removed.
(LL_SC_FMT): New define.
(COP12_FMT): Updated.
(ISA_IS_R6): New define.
(ISA_HAS_64BIT_REGS): Add mips64r6.
(ISA_HAS_DROR): Likewise.
(ISA_HAS_64BIT_FPRS): Add mips32r6 and mips64r6.
(ISA_HAS_ROR): Likewise.
(ISA_HAS_ODD_SINGLE_FPR): Likewise.
(ISA_HAS_MXHC1): Likewise.
(hilo_interlocks): Likewise.
(md_longopts): Likewise.
(ISA_HAS_LEGACY_NAN): New define.
(options): Add OPTION_MIPS32R6 and OPTION_MIPS64R6.
(mips_ase): Add field rem_rev.
(mips_ases): Updated to add which ISA an ASE was removed in.
(mips_isa_rev): Add support for mips32r6 and mips64r6.
(mips_check_isa_supports_ase): Add support to check if an ASE
has been removed in the specified MIPS ISA revision.
(validate_mips_insn): Skip '-' character.
(macro_build): Likewise.
(mips_check_options): Prevent R6 working with fp32, mips16,
micromips, or branch relaxation.
(file_mips_check_options): Set R6 floating point registers to
64 bit. Also deal with the nan2008 option.
(limited_pcrel_reloc_p): Add relocs: BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3,
BFD_RELOC_MIPS_19_PCREL_S2, BFD_RELOC_HI16_S_PCREL and
BFD_RELOC_LO16_PCREL.
(operand_reg_mask): Add support for OP_SAME_RS_RT, OP_CHECK_PREV
and OP_NON_ZERO_REG.
(match_check_prev_operand): New static function.
(match_same_rs_rt_operand): New static function.
(match_non_zero_reg_operand): New static function.
(match_operand): Added entries for: OP_SAME_RS_RT, OP_CHECK_PREV
and OP_NON_ZERO_REG.
(insns_between): Added case to deal with forbidden slots.
(append_insn): Added support for relocs: BFD_RELOC_MIPS_21_PCREL_S2
and BFD_RELOC_MIPS_26_PCREL_S2.
(match_insn): Add support for operands -A, -B, +' and +". Also
skip '-' character.
(mips_percent_op): Add entries for %pcrel_hi and %pcrel_lo.
(md_parse_option): Add support for mips32r6 and mips64r6. Also
update the nan option handling.
(md_pcrel_from): Add cases for relocs: BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2.
(mips_force_relocation): Prevent forced relaxation for MIPS r6.
(md_apply_fix): Add support for relocs: BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3,
BFD_RELOC_MIPS_19_PCREL_S2, BFD_RELOC_HI16_S_PCREL and
BFD_RELOC_LO16_PCREL.
(s_mipsset): Add support for mips32r6 and mips64r6.
(s_nan): Update to support the new nan2008 framework.
(tc_gen_reloc): Add relocs: BFD_RELOC_MIPS_21_PCREL_S2,
BFD_RELOC_MIPS_26_PCREL_S2, BFD_RELOC_MIPS_18_PCREL_S3,
BFD_RELOC_MIPS_19_PCREL_S2, BFD_RELOC_HI16_S_PCREL and
BFD_RELOC_LO16_PCREL.
(mips_elf_final_processing): Updated to use the mips_nan2008.
(mips_cpu_info_table): Add entries for mips32r6 and mips64r6.
(macro): Enable ldc2, sdc2, ll, lld, swc2, sc, scd, cache, pref
macros for R6.
(mips_fix_adjustable): Make PC relative R6 relocations relative
to the symbol and not the section.
* configure.ac: Add support for mips32r6 and mips64r6.
* configure: Regenerate.
* doc/c-mips.texi: Document the -mips32r6 and -mips64r6 command line
options.
* doc/as.texinfo: Likewise.
gas/testsuite/
* gas/mips/24k-triple-stores-1.s: If testing for r6 prevent
non-supported instructions from being tested.
* gas/mips/24k-triple-stores-2.s: Likewise.
* gas/mips/24k-triple-stores-3.s: Likewise.
* gas/mips/24k-triple-stores-6.s: Likewise.
* gas/mips/beq.s: Likewise.
* gas/mips/eva.s: Likewise.
* gas/mips/ld-zero-3.s: Likewise.
* gas/mips/mips32-cp2.s: Likewise.
* gas/mips/mips32.s: Likewise.
* gas/mips/mips4.s: Likewise.
* gas/mips/add.s: Don't test the add instructions if r6, and
add padding.
* gas/mips/add.d: Check for a triple dot not a nop at the end of the
disassembly output.
* gas/mips/micromips@add.d: Likewise.
* gas/mips/mipsr6@24k-branch-delay-1.d: New file.
* gas/mips/mipsr6@24k-triple-stores-1.d: New file.
* gas/mips/mipsr6@24k-triple-stores-2-llsc.d: New file.
* gas/mips/mipsr6@24k-triple-stores-2.d: New file.
* gas/mips/mipsr6@24k-triple-stores-3.d: New file.
* gas/mips/mipsr6@24k-triple-stores-6.d: New file.
* gas/mips/mipsr6@add.d: New file.
* gas/mips/mipsr6@attr-gnu-4-1-msingle-float.l: New file.
* gas/mips/mipsr6@attr-gnu-4-1-msingle-float.s: New file.
* gas/mips/mipsr6@attr-gnu-4-1-msoft-float.l: New file.
* gas/mips/mipsr6@attr-gnu-4-1-msoft-float.s: New file.
* gas/mips/mipsr6@attr-gnu-4-2-mdouble-float.l: New file.
* gas/mips/mipsr6@attr-gnu-4-2-mdouble-float.s: New file.
* gas/mips/mipsr6@beq.d: New file.
* gas/mips/mipsr6@bge.d: New file.
* gas/mips/mipsr6@bgeu.d: New file.
* gas/mips/mipsr6@blt.d: New file.
* gas/mips/mipsr6@bltu.d: New file.
* gas/mips/mipsr6@branch-misc-1.d: New file.
* gas/mips/mipsr6@branch-misc-2-64.d: New file.
* gas/mips/mipsr6@branch-misc-2pic-64.d: New file.
* gas/mips/mipsr6@branch-misc-4-64.d: New file.
* gas/mips/mipsr6@cache.d: New file.
* gas/mips/mipsr6@eva.d: New file.
* gas/mips/mipsr6@jal-svr4pic-noreorder.d: New file.
* gas/mips/mipsr6@jal-svr4pic.d: New file.
* gas/mips/mipsr6@ld-zero-2.d: New file.
* gas/mips/mipsr6@ld-zero-3.d: New file.
* gas/mips/mipsr6@loc-swap-dis.d: New file.
* gas/mips/mipsr6@mips32-cp2.d: New file.
* gas/mips/mipsr6@mips32-imm.d: New file.
* gas/mips/mipsr6@mips32.d: New file.
* gas/mips/mipsr6@mips32r2.d: New file.
* gas/mips/mipsr6@mips4-fp.d: New file.
* gas/mips/mipsr6@mips4-fp.l: New file.
* gas/mips/mipsr6@mips4-fp.s: New file.
* gas/mips/mipsr6@mips4.d: New file.
* gas/mips/mipsr6@mips5-fp.d: New file.
* gas/mips/mipsr6@mips5-fp.l: New file.
* gas/mips/mipsr6@mips5-fp.s: New file.
* gas/mips/mipsr6@mips64.d: New file.
* gas/mips/mipsr6@msa-branch.d: New file.
* gas/mips/mipsr6@msa.d: New file.
* gas/mips/mipsr6@pref.d: New file.
* gas/mips/mipsr6@relax-swap3.d: New file.
* gas/mips/r6-64-n32.d: New file.
* gas/mips/r6-64-n64.d: New file.
* gas/mips/r6-64-removed.l: New file.
* gas/mips/r6-64-removed.s: New file.
* gas/mips/r6-64.s: New file.
* gas/mips/r6-attr-none-double.d: New file.
* gas/mips/r6-n32.d: New file.
* gas/mips/r6-n64.d: New file.
* gas/mips/r6-removed.l: New file.
* gas/mips/r6-removed.s: New file.
* gas/mips/r6.d: New file.
* gas/mips/r6.s: New file.
* gas/mips/mipsr6@mips32-dsp.d: New file.
* gas/mips/mipsr6@mips32-dspr2.d: New file.
* gas/mips/mipsr6@mips32r2-ill.l: New file.
* gas/mips/mipsr6@mips32r2-ill.s: New file.
* gas/mips/cache.s: Add r6 instruction varients.
* gas/mips/mips.exp: Add support for the mips32r6 and mips64r6
architectures. Also prevent non r6 supported tests from running.
Finally, add in support for running the new r6 tests.
(run_dump_test_arch): Add support for mipsr6 tests.
(run_list_test_arch): Add support for using files of the
form arch@testname.l .
include/elf/
* mips.h: Add relocs: R_MIPS_PC21_S2, R_MIPS_PC26_S2, R_MIPS_PC18_S3,
R_MIPS_PC19_S2, R_MIPS_PCHI16 and R_MIPS_PCLO16.
(E_MIPS_ARCH_32R6): New define.
(E_MIPS_ARCH_64R6): New define.
include/opcode/
* mips.h (mips_operand_type): Add new entries: OP_SAME_RS_RT,
OP_CHECK_PREV and OP_NON_ZERO_REG. Add descriptions for the MIPS R6
instruction arguments: -a, -b, -d, -s, -t, -u, -v, -w, -x, -y, -A, -B,
+I, +O, +R, +:, +\, +", +;
(mips_check_prev_operand): New struct.
(INSN2_FORBIDDEN_SLOT): New define.
(INSN_ISA32R6): New define.
(INSN_ISA64R6): New define.
(INSN_UPTO32R6): New define.
(INSN_UPTO64R6): New define.
(mips_isa_table): Add INSN_UPTO32R6 and INSN_UPTO64R6.
(ISA_MIPS32R6): New define.
(ISA_MIPS64R6): New define.
(CPU_MIPS32R6): New define.
(CPU_MIPS64R6): New define.
(cpu_is_member): Add cases for CPU_MIPS32R6, and CPU_MIPS64R6.
ld/
* ldmain.c (get_emulation): Add support for -mips32r6 and -mips64r6.
opcodes/
* mips-dis.c (mips_arch_choices): Add entries for mips32r6 and
mips64r6.
(parse_mips_dis_option): Allow MSA and virtualization support for
mips64r6.
(mips_print_arg_state): Add fields dest_regno and seen_dest.
(mips_seen_register): New function.
(print_insn_arg): Refactored code to use mips_seen_register
function. Add support for OP_SAME_RS_RT, OP_CHECK_PREV and
OP_NON_ZERO_REG. Changed OP_REPEAT_DEST_REG case to print out
the register rather than aborting.
(print_insn_args): Add length argument. Add code to correctly
calculate the instruction address for pc relative instructions.
(validate_insn_args): New static function.
(print_insn_mips): Prevent jalx disassembling for r6. Use
validate_insn_args.
(print_insn_micromips): Use validate_insn_args.
all the arguments are valid.
* mips-formats.h (PREV_CHECK): New define.
* mips-opc.c (decode_mips_operand): Add support for -a, -b, -d, -s,
-t, -u, -v, -w, -x, -y, -A, -B, +I, +O, +R, +:, +\, +", +;
(RD_pc): New define.
(FS): New define.
(I37): New define.
(I69): New define.
(mips_builtin_opcodes): Add MIPS R6 instructions. Exclude recoded
MIPS R6 instructions from MIPS R2 instructions.
* elfxx-mips.h (_bfd_mips_elf_get_synthetic_symtab): New
prototype.
* elf32-mips.c (elf_backend_plt_sym_val): Remove macro.
(bfd_elf32_get_synthetic_symtab): New macro.
* elfxx-mips.c (plt_entry): New structure.
(mips_elf_link_hash_entry): Add use_plt_entry member.
(mips_elf_link_hash_table): Rename plt_entry_size member to
plt_mips_entry_size. Add plt_comp_entry_size, plt_mips_offset,
plt_comp_offset, plt_got_index entries and plt_header_is_comp
members.
(STUB_LW_MICROMIPS, STUB_MOVE_MICROMIPS): New macros.
(STUB_LUI_MICROMIPS, STUB_JALR_MICROMIPS): Likewise.
(STUB_ORI_MICROMIPS, STUB_LI16U_MICROMIPS): Likewise.
(STUB_LI16S_MICROMIPS): Likewise.
(MICROMIPS_FUNCTION_STUB_NORMAL_SIZE): Likewise.
(MICROMIPS_FUNCTION_STUB_BIG_SIZE): Likewise.
(micromips_o32_exec_plt0_entry): New variable.
(mips16_o32_exec_plt_entry): Likewise.
(micromips_o32_exec_plt_entry): Likewise.
(mips_elf_link_hash_newfunc): Initialize use_plt_entry.
(mips_elf_output_extsym): Update to use gotplt_union's plist
member rather than offset.
(mips_elf_gotplt_index): Likewise. Remove the VxWorks
restriction. Use MIPS_ELF_GOT_SIZE to calculate GOT address.
(mips_elf_count_got_symbols): Update to use gotplt_union's plist
member rather than offset.
(mips_elf_calculate_relocation): Handle MIPS16/microMIPS PLT
entries.
(_bfd_mips_elf_create_dynamic_sections): Don't set PLT sizes
here.
(mips_elf_make_plt_record): New function.
(_bfd_mips_elf_check_relocs): Update comment. Record occurences
of JAL relocations that might need a PLT entry.
(_bfd_mips_elf_adjust_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Set individual
PLT entry sizes here. Handle MIPS16/microMIPS PLT entries.
Don't set the symbol's value in the symbol table for PLT
references here. Don't set the PLT or PLT GOT section sizes
here.
(mips_elf_estimate_stub_size): Handle microMIPS stubs.
(mips_elf_allocate_lazy_stub): Likewise.
(mips_elf_lay_out_lazy_stubs): Likewise. Define a _MIPS_STUBS_
magic symbol.
(mips_elf_set_plt_sym_value): New function.
(_bfd_mips_elf_size_dynamic_sections): Set PLT header size and
PLT and PLT GOT section sizes here. Set the symbol values in
the symbol table for PLT references here. Handle microMIPS
annotation of the _PROCEDURE_LINKAGE_TABLE_ magic symbol.
(_bfd_mips_elf_finish_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Handle
MIPS16/microMIPS PLT entries. Handle microMIPS stubs.
(_bfd_mips_vxworks_finish_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Use
MIPS_ELF_GOT_SIZE to calculate GOT address.
(mips_finish_exec_plt): Handle microMIPS PLT. Return status.
(_bfd_mips_elf_finish_dynamic_sections): Handle result from
mips_finish_exec_plt.
(_bfd_mips_elf_link_hash_table_create): Update to use
gotplt_union's plist member rather than offset.
(_bfd_mips_elf_get_synthetic_symtab): New function.
include/elf/
* mips.h (ELF_ST_IS_MIPS_PLT): Respect STO_MIPS16 setting.
(ELF_ST_SET_MIPS_PLT): Likewise.
gdb/
* mips-tdep.c (mips_elf_make_msymbol_special): Handle MIPS16 and
microMIPS synthetic symbols.
ld/
* emulparams/elf32btsmip.sh: Arrange for .got.plt to be placed
as close to .plt as possible.
* scripttempl/elf.sc: Handle $INITIAL_READWRITE_SECTIONS and
$PLT_NEXT_DATA variables.
ld/testsuite/
* ld-mips-elf/jalx-2.dd: Update for microMIPS PLT support.
* ld-mips-elf/pic-and-nonpic-3a.dd: Update for the _MIPS_STUBS_
magic symbol.
* ld-mips-elf/pic-and-nonpic-3b.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-n32.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-n64.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-o32.dd: Likewise.
* ld-mips-elf/stub-dynsym-1-10000.d: Likewise.
* ld-mips-elf/stub-dynsym-1-2fe80.d: Likewise.
* ld-mips-elf/stub-dynsym-1-7fff.d: Likewise.
* ld-mips-elf/stub-dynsym-1-8000.d: Likewise.
* ld-mips-elf/stub-dynsym-1-fff0.d: Likewise.
* ld-mips-elf/tlslib-o32.d: Likewise.
opcodes/
* mips-dis.c (is_mips16_plt_tail): New function.
(print_insn_mips16): Handle MIPS16 PLT entry's GOT slot address
word.
(is_compressed_mode_p): Handle MIPS16/microMIPS PLT entries.
PR corefile/8210
bfd/
* bfd-in2.h: Regenerate.
* corefile.c (bfd_core_file_pid): New.
* targets.c (BFD_JUMP_TABLE_CORE): Add NAME##_core_file_pid.
(struct bfd_target) <_core_file_pid>: New.
* libbfd-in.h (_bfd_nocore_core_file_pid): Declare.
* libbfd.c (_bfd_nocore_core_file_pid): New.
* elf-bfd.h (bfd_elf32_core_file_pid, bfd_elf64_core_file_pid):
Declare.
* elfcode.h (elf_core_file_pid): New define.
* elfcore.h (elf_core_file_pid): New function.
* elf.c (elfcore_make_pid): Rewrite.
(elfcore_grok_prstatus): Only set core_pid if not set yet.
(elfcore_grok_prstatus) [!HAVE_PRSTATUS_T_PR_WHO]: Fallback to
getting the lwpid from prstat.pr_pid.
* elf64-x86-64.c (elf64_x86_64_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
(elf64_x86_64_grok_psinfo): Extract the the main process's PID,
and store it in elf_tdata's core_pid field.
* elf32-i386.c (elf_i386_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
(elf_i386_grok_psinfo): Extract the the main process's PID, and
store it in elf_tdata's core_pid field.
* elf32-am33lin.c (elf32_am33lin_grok_prstatus): Write the LWPID
to elf_tdata's core_lwpid instead of to core_pid.
* elf32-arm.c (elf32_arm_nabi_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-cris.c (cris_elf_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-frv.c (elf32_frv_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-hppa.c (elf32_hppa_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-mips.c (elf32_mips_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-ppc.c (ppc_elf_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-s390.c (elf_s390_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-score.c (s3_bfd_score_elf_grok_prstatus): Write the LWPID
to elf_tdata's core_lwpid instead of to core_pid.
* elf32-score7.c (s7_bfd_score_elf_grok_prstatus): Write the LWPID
to elf_tdata's core_lwpid instead of to core_pid.
* elf32-sh.c (elf32_shlin_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf32-xtensa.c (elf_xtensa_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf64-hppa.c (elf64_hppa_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf64-mips.c (elf64_mips_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elf64-ppc.c (ppc64_elf_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* elfn32-mips.c (elf32_mips_grok_prstatus): Write the LWPID to
elf_tdata's core_lwpid instead of to core_pid.
* plugin.c (bfd_plugin_core_file_pid): New function.
* aout-target.h (MY_core_file_pid): Define.
* aout-tic30.c (MY_core_file_pid, MY_core_file_p): New defines.
* coff-rs6000.c (coff_core_file_pid): New define.
(rs6000coff_vec, pmac_xcoff_vec): Use BFD_JUMP_TABLE_CORE.
* coff64-rs6000.c (coff_core_file_pid): New define.
(rs6000coff64_vec): Use BFD_JUMP_TABLE_CORE.
(xcoff64_core_file_pid): New define.
(aix5coff64_vec): Use BFD_JUMP_TABLE_CORE.
* mach-o-target.c (bfd_mach_o_core_file_pid): New define.
* aix386-core.c (aix386_core_file_pid): New define.
* hppabsd-core.c (hppabsd_core_core_file_pid): New define.
* hpux-core.c (hpux_core_core_file_pid): New define.
* irix-core.c (irix_core_core_file_pid): New define.
* lynx-core.c (lynx_core_file_pid): New define.
* osf-core.c (osf_core_core_file_pid): New define.
* ptrace-core.c (ptrace_unix_core_file_pid): New define.
* sco5-core.c (sco5_core_file_pid): New define.
* xcoff-target.h (coff_core_file_pid): New define.
* netbsd-core.c (netbsd_core_core_file_pid): New define.
gdb/
2010-08-18 Pedro Alves <pedro@codesourcery.com>
PR corefile/8210
gdb/
* corelow.c (add_to_thread_list): Don't use
gdbarch_core_reg_section_encodes_pid. Use bfd_core_file_pid.
(get_core_register_section): Don't use
gdbarch_core_reg_section_encodes_pid.
* gdbarch.sh (core_reg_section_encodes_pid): Delete.
* gdbarch.h, gdbarch.c: Regenerate.
* amd64-sol2-tdep.c (amd64_sol2_init_abi): Don't set
gdbarch_core_reg_section_encodes_pid.
* i386-sol2-tdep.c (i386_sol2_init_abi): Ditto.
* sparc-sol2-tdep.c (sparc32_sol2_init_abi): Ditto.
* sparc64-sol2-tdep.c (sparc64_sol2_init_abi): Ditto.
* elf32-mips.c (mips_reloc_map): Add BFD_RELOC_MIPS_JALR.
* elfxx-mips.c (JAL_TO_BAL_P): New define to transform JAL to BAL
for CPUs. It is true for RM9000.
(JALR_TO_BAL_P): New define to transform JALR to BAL. It is true
for all CPUs.
(mips_elf_perform_relocation): Use JAL_TO_BAL_P and JALR_TO_BAL_P
to guard the transformation.