_init and _fini are special functions provided by glibc for linker to
define DT_INIT and DT_FINI in executable and shared library. They
should never be put in dynamic symbol table. This patch marks them as
hidden to remove them from dynamic symbol table.
Tested with build-many-glibcs.py.
[BZ #23145]
* elf/Makefile (tests-special): Add $(objpfx)check-initfini.out.
($(all-built-dso:=.dynsym): New target.
(common-generated): Add $(all-built-dso:$(common-objpfx)%=%.dynsym).
($(objpfx)check-initfini.out): New target.
(generated): Add check-initfini.out.
* scripts/check-initfini.awk: New file.
* sysdeps/aarch64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/alpha/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/arm/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/hppa/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/i386/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/ia64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/m68k/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/microblaze/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips64/n32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips64/n64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/nios2/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/powerpc/powerpc32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/powerpc/powerpc64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/s390/s390-32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/s390/s390-64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/sh/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/sparc/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/x86_64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
Wrap symbol address run-time calculation into a macro and use it
throughout, replacing inline calculations.
There are a couple of variants, most of them different in a functionally
insignificant way. Most calculations are right following RESOLVE_MAP,
at which point either the map or the symbol returned can be checked for
validity as the macro sets either both or neither. In some places both
the symbol and the map has to be checked however.
My initial implementation therefore always checked both, however that
resulted in code larger by as much as 0.3%, as many places know from
elsewhere that no check is needed. I have decided the size growth was
unacceptable.
Having looked closer I realized that it's the map that is the culprit.
Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional
boolean argument telling it to access the map without checking it for
validity. This in turn has brought quite nice results, with new code
actually being smaller for i686, and MIPS o32, n32 and little-endian n64
targets, unchanged in size for x86-64 and, unusually, marginally larger
for big-endian MIPS n64, as follows:
i686:
text data bss dec hex filename
152255 4052 192 156499 26353 ld-2.27.9000-base.so
152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so
MIPS/o32/el:
text data bss dec hex filename
142906 4396 260 147562 2406a ld-2.27.9000-base.so
142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so
MIPS/n32/el:
text data bss dec hex filename
142267 4404 260 146931 23df3 ld-2.27.9000-base.so
142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so
MIPS/n64/el:
text data bss dec hex filename
149835 7376 408 157619 267b3 ld-2.27.9000-base.so
149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so
MIPS/o32/eb:
text data bss dec hex filename
142870 4396 260 147526 24046 ld-2.27.9000-base.so
142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so
MIPS/n32/eb:
text data bss dec hex filename
142019 4404 260 146683 23cfb ld-2.27.9000-base.so
141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so
MIPS/n64/eb:
text data bss dec hex filename
149763 7376 408 157547 2676b ld-2.27.9000-base.so
149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so
x86-64:
text data bss dec hex filename
148462 6452 400 155314 25eb2 ld-2.27.9000-base.so
148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so
[BZ #19818]
* sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set'
parameter.
(SYMBOL_ADDRESS): New macro.
[!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use
SYMBOL_ADDRESS for symbol address calculation.
* elf/dl-runtime.c (_dl_fixup): Likewise.
(_dl_profile_fixup): Likewise.
* elf/dl-symaddr.c (_dl_symbol_address): Likewise.
* elf/rtld.c (dl_main): Likewise.
* sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise.
(elf_machine_rela): Likewise.
* sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise.
* sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise.
(elf_machine_rela): Likewise.
* sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC):
Likewise.
(elf_machine_reloc): Likewise.
(elf_machine_got_rel): Likewise.
* sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise.
* sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
In _dl_runtime_resolve[_vx], unwinding fails after the new stack frame
is created as there is no CFI rule for r15. This is also observeable in
GDB: Backtrace stopped: previous frame inner to this frame (corrupt stack?)
Therefore this patch is now storing r15 on stack and is using cfi_offset rule.
The stmg/lmg instruction is used to store/load r14 and r15 with one instruction.
On 64bit, the offsets of the fprs have moved to store r15 directly after r14.
On 31bit, the r14/r15 is now stored between the other gprs and fprs as the space
wasn't used.
ChangeLog:
* sysdeps/s390/s390-64/dl-trampoline.h (_dl_runtime_resolve):
Store r15 on stack and add cfi rule.
* sysdeps/s390/s390-32/dl-trampoline.h (_dl_runtime_resolve):
Likewise.
GDB failed to detect the outermost frame while showing the backtrace
within a thread:
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
Before this patch, the start routines like thread_start had no cfi information.
GDB is then using the prologue unwinder if no cfi information is available.
This unwinder tries to unwind r15 and stops e.g. if r15 was updated or
on some jump-instructions.
On older glibc-versions (before commit "Remove cached PID/TID in clone"
c579f48edb), the thread_start function used
such a jump-instruction and GDB did not fail with an error.
This patch adds cfi information for _start, thread_start and __makecontext_ret
and marks r14 as undefined which marks the frame as outermost frame and GDB
stops the backtrace. Also tested different gcc versions in order to test
_Unwind_Backtrace() in libgcc as this is used by backtrace() in glibc.
ChangeLog:
* sysdeps/s390/s390-64/start.S (_start): Add cfi information for r14.
* sysdeps/s390/s390-32/start.S: (_start): Likewise
* sysdeps/unix/sysv/linux/s390/s390-64/clone.S
(thread_start): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/clone.S
(thread_start): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S
(__makecontext_ret): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
(__makecontext_ret): Likewise.
The testcases elf/tst-tls1-static and elf/tst-tls2-static
are failing on s390 if gcc is configured with --enable-default-pie.
According to binutils, there are only four valid cases for IE -> LE transition:
lg %rx,(0,%ry) -> sllg %rx,%ry,0
lg %rx,(%ry,0) -> sllg %rx,%ry,0
lg %rx,(%ry,%r12) -> sllg %rx,%ry,0
lg %rx,(%r12,%ry) -> sllg %rx,%ry,0
Thus I've adjusted the TLS_IE macro in s390 tls-macros.h files in PIC case
in order to use r12 for the address of global offset table.
The adjusted macro definition is not used if gcc is not configured with
--enable-default-pie.
ChangeLog:
* sysdeps/s390/s390-32/tls-macros.h (TLS_IE): Use r12 for GOT address.
* sysdeps/s390/s390-64/tls-macros.h (TLS_IE): Likewise.
Building glibc with gcc configured with --enable-default-pie failed on s390
due to assembler messages:
../sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S:44:
Error: junk at end of line, first unrecognized character is `@'
HIDDEN_JUMPTARGET was expanded to exit@PLT@GOTOFF.
If SHARED is not defined, HIDDEN_JUMPTARGET is defined to JUMPTARGET
in sysdeps/s390/s390-32/sysdep.h. There it expanded to exit@PLT
in non SHARED case as PIC is defined if gcc is configured with
--enable-default-pie. Thus I've changed the "ifdef PIC" to "ifdef SHARED"
as we do not want PLTs in the static obj files. I've also changed this
in sysdeps/s390/s390-64/sysdep.h.
I've also adjusted sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S.
If glibc is configured with --disable-hidden-plt, then NO_HIDDEN is defined.
In SHARED case HIDDEN_JUMPTARGET would be expanded to exit@PLT@GOTOFF
instead of __GI_exit@GOTOFF.
Now we jump to:
- __GI_exit if SHARED is defined
- exit@PLT if SHARED and NO_HIDDEN is defined
- exit if both are not defined.
On s390 31bit we have to setup GOT pointer in r12 if we use a PLT stub.
Therefore I use SYSCALL_PIC_SETUP from sysdep.h and added the missing semicolons.
ChangeLog:
[BZ #21537]
* sysdeps/s390/s390-32/sysdep.h (JUMPTARGET, SYSCALL_PIC_SETUP):
Check SHARED instead of PIC.
(SYSCALL_PIC_SETUP): Add missing semicolons.
* sysdeps/s390/s390-64/sysdep.h (JUMPTARGET, SYSCALL_PIC_SETUP):
Check SHARED instead of PIC.
* sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
(__makecontext_ret): Adjust code to jump to exit.
ELFv2 functions with localentry:0 are those with a single entry point,
ie. global entry == local entry, that have no requirement on r2 or
r12 and guarantee r2 is unchanged on return. Such an external
function can be called via the PLT without saving r2 or restoring it
on return, avoiding a common load-hit-store for small functions.
This patch implements the ld.so changes necessary for this
optimization. ld.so needs to check that an optimized plt call
sequence is in fact calling a function implemented with localentry:0,
end emit a fatal error otherwise.
The elf/testobj6.c change is to stop "error while loading shared
libraries: expected localentry:0 `preload'" when running
elf/preloadtest, which we'd get otherwise.
* elf/elf.h (PPC64_OPT_LOCALENTRY): Define.
* sysdeps/alpha/dl-machine.h (elf_machine_fixup_plt): Add
refsym and sym parameters. Adjust callers.
* sysdeps/aarch64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/arm/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/generic/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/hppa/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/i386/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/ia64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/m68k/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/microblaze/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/mips/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/nios2/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_fixup_plt):
Likewise.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/tile/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/x86_64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.c (_dl_error_localentry): New.
(_dl_reloc_overflow): Increase buffser size. Formatting.
* sysdeps/powerpc/powerpc64/dl-machine.h (ppc64_local_entry_offset):
Delete reloc param, add refsym and sym. Check optimized plt
call stubs for localentry:0 functions. Adjust callers.
(elf_machine_fixup_plt, elf_machine_plt_conflict): Add refsym
and sym parameters. Adjust callers.
(_dl_reloc_overflow): Move attribute.
(_dl_error_localentry): Declare.
* elf/dl-runtime.c (_dl_fixup): Save original sym. Pass
refsym and sym to elf_machine_fixup_plt.
* elf/testobj6.c (preload): Call printf.
As noted in [1], divdi3 object is only exported in a handful ABIs
(i386, m68k, powerpc32, s390-32, and ia64), however it is built
for all current architectures regardless.
This patch refact the make rules for this object to so only the
aforementioned architectures that actually require it builds it.
Also, to avoid internal PLT calls to the exported symbol from the
module, glibc uses an internal header (symbol-hacks.h) which is
unrequired (and in fact breaks the build for architectures that
intend to get symbol definitions from libgcc.a). The patch also
changes it to create its own header (divdi3-symbol-hacks.h) and
adjust the architectures that require it accordingly.
I checked the build/check (with run-built-tests=no) on the
following architectures (which I think must cover all supported
ABI/builds) using GCC 6.3:
aarch64-linux-gnu
alpha-linux-gnu
arm-linux-gnueabihf
hppa-linux-gnu
ia64-linux-gnu
m68k-linux-gnu
microblaze-linux-gnu
mips64-n32-linux-gnu
mips-linux-gnu
mips64-linux-gnu
nios2-linux-gnu
powerpc-linux-gnu
powerpc-linux-gnu-power4
powerpc64-linux-gnu
powerpc64le-linux-gnu
s390x-linux-gnu
s390-linux-gnu
sh4-linux-gnu
sh4-linux-gnu-soft
sparc64-linux-gnu
sparcv9-linux-gnu
tilegx-linux-gnu
tilegx-linux-gnu-32
tilepro-linux-gnu
x86_64-linux-gnu
x86_64-linux-gnu-x32
i686-linux-gnu
I only saw one regression on sparcv9-linux-gnu (extra PLT call to
.udiv) which I address in next patch in the set. It also correctly
build SH with GCC 7.0.1 (without any regression from c89721e25d).
[1] https://sourceware.org/ml/libc-alpha/2017-03/msg00243.html
* sysdeps/i386/symbol-hacks.h: New file.
* sysdeps/m68k/symbol-hacks.h: New file.
* sysdeps/powerpc/powerpc32/symbol-hacks.h: New file.
* sysdeps/s390/s390-32/symbol-hacks.h: New file.
* sysdeps/unix/sysv/linux/i386/Makefile
[$(subdir) = csu] (sysdep_routines): New rule: divdi3 object.
[$(subdir) = csu] (sysdep-only-routines): Likewise.
[$(subdir) = csu] (CFLAGS-divdi3.c): Likewise.
* sysdeps/unix/sysv/linux/m68k/Makefile
[$(subdir) = csu] (sysdep_routines): Likewise.
[$(subdir) = csu] (sysdep-only-routines): Likewise.
[$(subdir) = csu] (CFLAGS-divdi3.c): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/Makefile
[$(subdir) = csu] (sysdep_routines): Likewise.
[$(subdir) = csu] (sysdep-only-routines): Likewise.
[$(subdir) = csu] (CFLAGS-divdi3.c): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/Makefile
[$(subdir) = csu] (sysdep_routines): Likewise.
[$(subdir) = csu] (sysdep-only-routines): Likewise.
[$(subdir) = csu] (CFLAGS-divdi3.c): Likewise.
* sysdeps/wordsize-32/Makefile: Remove file.
* sysdeps/wordsize-32/symbol-hacks.h: Definitions move to ...
* sysdeps/wordsize-32/divdi3-symbol-hacks.h: ... here.
This patch also clobbers r14 in TLS_LD, TLS_GD macros on 31bit.
This ensures that r14 isn't used to save and restore r12 while
r14 is clobbered by the bas-instruction.
As note:
r12 can't be added to clobber list as gcc would fail with:
error: PIC register clobbered by ‘12’ in ‘asm’
For 64bit this fix was already done in 2004 in the
commit b80af23ac6.
ChangeLog:
* sysdeps/s390/s390-32/tls-macros.h (TLS_LD, TLS_GD):
Clobber also r14.
Information about whether the ABI of long double is the same as that
of double is split between bits/mathdef.h and bits/wordsize.h.
When the ABIs are the same, bits/mathdef.h defines
__NO_LONG_DOUBLE_MATH. In addition, in the case where the same glibc
binary supports both -mlong-double-64 and -mlong-double-128,
bits/wordsize.h defines __LONG_DOUBLE_MATH_OPTIONAL, along with
__NO_LONG_DOUBLE_MATH if this particular compilation is with
-mlong-double-64.
As part of the refactoring I proposed in
<https://sourceware.org/ml/libc-alpha/2016-11/msg00745.html>, this
patch puts all that information in a single header,
bits/long-double.h. It is included from sys/cdefs.h alongside the
include of bits/wordsize.h, so other headers generally do not need to
include bits/long-double.h directly.
Previously, various bits/mathdef.h headers and bits/wordsize.h headers
had this long double information (including implicitly in some
bits/mathdef.h headers through not having the defines present in the
default version). After the patch, it's all in six bits/long-double.h
headers. Furthermore, most of those new headers are not
architecture-specific. Architectures with optional long double all
use the ldbl-opt sysdeps directory, either in the order (ldbl-64-128,
ldbl-opt, ldbl-128) or (ldbl-128ibm, ldbl-opt). Thus a generic header
for the case where long double = double, and headers in ldbl-128,
ldbl-96 and ldbl-opt, suffices to cover every architecture except for
cases where long double properties vary between different ABIs sharing
a set of installed headers; fortunately all the ldbl-opt cases share a
single compiler-predefined macro __LONG_DOUBLE_128__ that can be used
to tell whether this compilation is -mlong-double-64 or
-mlong-double-128.
The two cases where a set of headers is shared between ABIs with
different long double properties, MIPS (o32 has long double = double,
other ABIs use ldbl-128) and SPARC (32-bit has optional long double,
64-bit has required long double), need their own bits/long-double.h
headers.
As with bits/wordsize.h, multiple-include protection for this header
is generally implicit through the include guards on sys/cdefs.h, and
multiple inclusion is harmless in any case. There is one subtlety:
the header must not define __LONG_DOUBLE_MATH_OPTIONAL if
__NO_LONG_DOUBLE_MATH was defined before its inclusion, because doing
so breaks how sysdeps/ieee754/ldbl-opt/nldbl-compat.h defines
__NO_LONG_DOUBLE_MATH itself before including system headers. Subject
to keeping that working, it would be reasonable to move these macros
from defined/undefined #ifdef to always-defined 1/0 #if semantics, but
this patch does not attempt to do so, just rearranges where the macros
are defined.
After this patch, the only use of bits/mathdef.h is the alpha one for
modifying complex function ABIs for old GCC. Thus, all versions of
the header other than the default and alpha versions are removed, as
is the include from math.h.
Tested for x86_64 and x86. Also did compilation-only testing with
build-many-glibcs.py.
* bits/long-double.h: New file.
* sysdeps/ieee754/ldbl-128/bits/long-double.h: Likewise.
* sysdeps/ieee754/ldbl-96/bits/long-double.h: Likewise.
* sysdeps/ieee754/ldbl-opt/bits/long-double.h: Likewise.
* sysdeps/mips/bits/long-double.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/long-double.h: Likewise.
* math/Makefile (headers): Add bits/long-double.h.
* misc/sys/cdefs.h: Include <bits/long-double.h>.
* stdlib/strtold.c: Include <bits/long-double.h> instead of
<bits/wordsize.h>.
* bits/mathdef.h [!_COMPLEX_H]: Do not allow inclusion.
[!__NO_LONG_DOUBLE_MATH]: Remove conditional code.
* math/math.h: Do not include <bits/mathdef.h>.
* sysdeps/aarch64/bits/mathdef.h: Remove file.
* sysdeps/alpha/bits/mathdef.h [!_COMPLEX_H]: Do not allow
inclusion.
* sysdeps/ia64/bits/mathdef.h: Remove file.
* sysdeps/m68k/m680x0/bits/mathdef.h: Likewise.
* sysdeps/mips/bits/mathdef.h: Likewise.
* sysdeps/powerpc/bits/mathdef.h: Likewise.
* sysdeps/s390/bits/mathdef.h: Likewise.
* sysdeps/sparc/bits/mathdef.h: Likewise.
* sysdeps/x86/bits/mathdef.h: Likewise.
* sysdeps/s390/s390-32/bits/wordsize.h
[!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Remove
conditional code.
* sysdeps/s390/s390-64/bits/wordsize.h
[!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]:
Likewise.
* sysdeps/unix/sysv/linux/alpha/bits/wordsize.h
[!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/bits/wordsize.h
[!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]:
Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/wordsize.h
[!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]:
Likewise.
This patch adjusts the s390 specific ifunc helper macros in ifunc-resolve.h to
use the common __ifunc macro, which uses gcc attribute ifunc to get rid of the
false debuginfo. Therefore the redirection construct is applied where needed.
Perhaps in future we can switch some of the internal symbols __GI_* from the
fallback variant to the ifunc function. But this change is not
straightforward due to a segmentation fault while linking libc.so with older
binutils on s390.
ChangeLog:
[BZ #20478]
* sysdeps/s390/multiarch/ifunc-resolve.h
(s390_vx_libc_ifunc2, s390_libc_ifunc): Use __ifunc from libc-symbols.h
to create ifunc symbols.
(s390_vx_libc_ifunc_init, s390_vx_libc_ifunc_redirected
, s390_vx_libc_ifunc2_redirected, s390_libc_ifunc_init): New define.
* sysdeps/s390/multiarch/memchr.c: Redirect ifunced function in header
for using it as type for ifunc function.
* sysdeps/s390/multiarch/mempcpy.c: Likewise.
* sysdeps/s390/multiarch/rawmemchr.c: Likewise.
* sysdeps/s390/multiarch/stpcpy.c: Likewise.
* sysdeps/s390/multiarch/stpncpy.c: Likewise.
* sysdeps/s390/multiarch/strcat.c: Likewise.
* sysdeps/s390/multiarch/strchr.c: Likewise.
* sysdeps/s390/multiarch/strcmp.c: Likewise.
* sysdeps/s390/multiarch/strcpy.c: Likewise.
* sysdeps/s390/multiarch/strcspn.c: Likewise.
* sysdeps/s390/multiarch/strlen.c: Likewise.
* sysdeps/s390/multiarch/strncmp.c: Likewise.
* sysdeps/s390/multiarch/strncpy.c: Likewise.
* sysdeps/s390/multiarch/strnlen.c: Likewise.
* sysdeps/s390/multiarch/strpbrk.c: Likewise.
* sysdeps/s390/multiarch/strrchr.c: Likewise.
* sysdeps/s390/multiarch/strspn.c: Likewise.
* sysdeps/s390/multiarch/wcschr.c: Likewise.
* sysdeps/s390/multiarch/wcscmp.c: Likewise.
* sysdeps/s390/multiarch/wcspbrk.c: Likewise.
* sysdeps/s390/multiarch/wcsspn.c: Likewise.
* sysdeps/s390/multiarch/wmemchr.c: Likewise.
* sysdeps/s390/multiarch/wmemset.c: Likewise.
* sysdeps/s390/s390-32/multiarch/memcmp.c: Likewise.
* sysdeps/s390/s390-32/multiarch/memcpy.c: Likewise.
* sysdeps/s390/s390-32/multiarch/memset.c: Likewise.
* sysdeps/s390/s390-64/multiarch/memcmp.c: Likewise.
* sysdeps/s390/s390-64/multiarch/memcpy.c: Likewise.
* sysdeps/s390/s390-64/multiarch/memset.c: Likewise.
If the default memcpy variant is called with a length of >1MB on 31bit,
r13 is clobbered as the algorithm is switching to mvcle. The mvcle code
returns without restoring r13. All other cases are restoring r13.
If memcpy is called from outside libc the ifunc resolver will only select
this variant if running on machines older than z10.
Otherwise or if memcpy is called from inside libc, this default memcpy
variant is called.
The testcase timezone/tst-tzset is triggering this issue in some combinations
of gcc versions and optimization levels.
This bug was introduced in commit 04bb21ac93
and thus is a regression compared to former glibc 2.23 release.
This patch removes the usage of r13 at all. Thus it is not saved and restored.
The base address for execute-instruction is now stored in r5 which is obtained
after r5 is not needed anymore as 256byte block counter.
ChangeLog:
* sysdeps/s390/s390-32/memcpy.S (memcpy): Eliminate the usage
of r13 as it is not restored in mvcle case.
On s390, the current prelink undo code in elf_machine_lazy_rel()
has the requirement, that the plt stubs use the first got slots
after the 3 reserved ones.
In case of undoing prelink, the plt got slots are reset to the correct
addresses whithin the corresponding plt-stub. Therefore the address
is calculated by the address of the first plt-stub-address which
was written by prelink (see l->l_mach.plt) to got[1] and index of
current relocation multiplied with 32 (=size of one plt slot).
The index was calculated with ¤t-got-slot - &got[3].
This patch removes the requirement, that the plt-got-slots are
starting at got[3]. The index is now calculated with
¤t-reloc - &reloc[0]. The first struct Elf64_Rela is stored
at DT_JMPREL.
This patch is needed to prepare for partial relro support.
Ulrich Weigand suggested this approach to use DT_JMPREL - Thanks.
ChangeLog:
* sysdeps/s390/linkmap.h (struct link_map_machine):
Remove member gotplt and add member jmprel.
* sysdeps/s390/s390-32/dl-machine.h
(elf_machine_runtime_setup): Setup member jmprel with DT_JMPREL
instead of gotplt with &got[3].
(elf_machine_lazy_rel): Calculate address with reloc and jmprel.
* sysdeps/s390/s390-64/dl-machine.h: Likewise.
There exist optimized memcpy functions on s390, but no optimized mempcpy.
This patch adds mempcpy entry points in memcpy.S files, which
use the memcpy implementation. Now mempcpy itself is also an IFUNC function
as memcpy is and the variants are listed in ifunc-impl-list.c.
The s390 string.h does not define _HAVE_STRING_ARCH_mempcpy.
Instead mempcpy string/string.h inlines memcpy() + n.
If n is constant and small enough, GCC emits instructions like mvi or mvc
and avoids the function call to memcpy.
If n is not constant, then memcpy is called and n is added afterwards.
If _HAVE_STRING_ARCH_mempcpy would be defined, mempcpy would be called in
every case.
According to PR70140 "Inefficient expansion of __builtin_mempcpy"
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70140) GCC should handle a
call to mempcpy in the same way as memcpy. Then either the mempcpy macro
in string/string.h has to be removed or _HAVE_STRING_ARCH_mempcpy has to
be defined for S390.
ChangeLog:
[BZ #19765]
* sysdeps/s390/mempcpy.S: New File.
* sysdeps/s390/multiarch/mempcpy.c: Likewise.
* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add mempcpy.
* sysdeps/s390/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list):
Add mempcpy variants.
* sysdeps/s390/s390-32/memcpy.S: Add mempcpy entry point.
(memcpy): Adjust to be usable from mempcpy entry point.
(__memcpy_mvcle): Likewise.
* sysdeps/s390/s390-64/memcpy.S: Likewise.
* sysdeps/s390/s390-32/multiarch/memcpy-s390.S: Add entry points
____mempcpy_z196, ____mempcpy_z10 and add __GI_ symbols for mempcpy.
(__memcpy_z196): Adjust to be usable from mempcpy entry point.
(__memcpy_z10): Likewise.
* sysdeps/s390/s390-64/multiarch/memcpy-s390x.S: Likewise.
On s390, the memcpy, memcmp, memset functions are IFUNC symbols,
which are created with s390_libc_ifunc-macro.
This macro creates a __GI_ symbol which is set to the
ifunced symbol. Thus calls within libc.so to e.g. memcpy
result in a call to *ABS*+0x954c0@plt stub and afterwards
to the resolved memcpy-ifunc-variant.
This patch sets the __GI_ symbol to the default-ifunc-variant
to avoid the plt call. The __GI_ symbols are now created at the
default variant of ifunced function.
ChangeLog:
* sysdeps/s390/multiarch/ifunc-resolve.h (s390_libc_ifunc):
Remove __GI_ symbol.
* sysdeps/s390/s390-32/multiarch/memcmp-s390.S: Add __GI_memcmp symbol.
* sysdeps/s390/s390-64/multiarch/memcmp-s390x.S: Likewise.
* sysdeps/s390/s390-32/multiarch/memcpy-s390.S: Add __GI_memcpy symbol.
* sysdeps/s390/s390-64/multiarch/memcpy-s390x.S: Likewise.
* sysdeps/s390/s390-32/multiarch/memset-s390.S: Add __GI_memset symbol.
* sysdeps/s390/s390-64/multiarch/memset-s390x.S: Likewise.
If more than 255 bytes should be copied, the algorithm jumps away.
Before this patch, it jumps to the mvc-loop (.L_G5_12).
Now it jumps first to the "> 1MB" check, which jumps away to
__memcpy_mvcle. Otherwise, the mvc-loop (.L_G5_12) copies the bytes.
ChangeLog:
* sysdeps/s390/s390-32/memcpy.S (memcpy):
Jump to 1MB check before executing mvc-loop.
if glibc is build with -march=z900 | -march=z990,
the startup file gcrt1.o (used if you link with gcc -pg)
contains R_390_GOT12 | R_390_GOT20 relocations.
Thus, an entry in the GOT can be addressed relative to the GOT pointer
with a 12 | 20 bit displacement value.
The startup files should not contain R_390_GOT12,
R_390_GOT20 relocations, but R_390_GOTENT ones.
This patch removes the overrides of pic-ccflag and
the default pic-ccflag = -fPIC in Makeconfig
is used instead to get the R_390_GOTENT relocations in gcrt1.o.
ChangeLog:
* sysdeps/s390/s390-32/Makefile (pic-ccflag): Remove.
* sysdeps/s390/s390-64/Makefile: Likewise.
This patch uses ahi instead of aghi in 32bit _dl_runtime_resolve
to adjust the stack pointer. This is no functional change,
but a cosmetic one.
ChangeLog:
* sysdeps/s390/s390-32/dl-trampoline.h (_dl_runtime_resolve):
Use ahi instead of aghi to adjust stack pointer.
Starting with z13, vector registers can also occur as argument registers.
Thus the passed input/output register structs for
la_s390_[32|64]_gnu_plt[enter|exit] functions should reflect those new
registers. This patch extends these structs La_s390_regs and La_s390_retval
and adjusts _dl_runtime_profile() to handle those fields in case of
running on a z13 machine.
ChangeLog:
* sysdeps/s390/bits/link.h: (La_s390_vr) New typedef.
(La_s390_32_regs): Append vector register lr_v24-lr_v31.
(La_s390_64_regs): Likewise.
(La_s390_32_retval): Append vector register lrv_v24.
(La_s390_64_retval): Likeweise.
* sysdeps/s390/s390-32/dl-trampoline.h (_dl_runtime_profile):
Handle extended structs La_s390_32_regs and La_s390_32_retval.
* sysdeps/s390/s390-64/dl-trampoline.h (_dl_runtime_profile):
Handle extended structs La_s390_64_regs and La_s390_64_retval.
On s390, no fpr/vrs were saved while resolving a symbol
via _dl_runtime_resolve/_dl_runtime_profile.
According to the abi, the fpr-arguments are defined as call clobbered.
In leaf-functions, gcc 4.9 and newer can use fprs for saving/restoring gprs
instead of saving them to the stack.
If gcc do this in one of the resolver-functions, then the floating point
arguments of a library-function are invalid for the first library-function-call.
Thus, this patch saves/restores the fprs around the resolving code.
The same could occur for vector registers. Furthermore an ifunc-resolver
could also clobber the vector/floating point argument registers.
Thus this patch provides the further variants _dl_runtime_resolve_vx/
_dl_runtime_profile_vx, which are used if the kernel claims, that
we run on a machine with vector registers.
Furthermore, if _dl_runtime_profile calls _dl_call_pltexit,
the pointers to inregs-/outregs-structs were setup invalid.
Now they point to the correct location in the stack-frame.
Before branching back to the caller, the return values are now
restored instead of containing the return values of the
_dl_call_pltexit() call.
On s390-32, an endless loop occurs if _dl_call_pltexit() should be called.
Now, this code-path branches to this function instead of just after the
preceding basr-instruction.
ChangeLog:
* sysdeps/s390/s390-32/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-32/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
if _dl_call_pltexit is called.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
* sysdeps/s390/s390-64/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-64/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
* sysdeps/s390/s390-64/dl-machine.h: (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
For each function setjmp, longjmp, getcontext, there exist a symbol
<func> and a default/versioned symbol <func>@@GLIBC_2.x in the build
obj-files.
This is wrong because it should only exist an unversioned or a
default-versioned symbol with the same name in an obj-file.
Glibc can't be build with recent binutils. See the already fixed linker
bug https://sourceware.org/bugzilla/show_bug.cgi?id=19073.
Nevertheless, this patch cleans this up.
Furthermore the BSD entry points setjmp, _setjmp were marked as weak,
but should be strong as on other architectures.
(see https://sourceware.org/ml/libc-alpha/2014-07/msg00568.html for an
older discussion with Andreas Schwab)
Some whitespace issues are corrected in sysdeps/s390/s390-64/setjmp.S,
too. But there is no change in the assembler code.
ChangeLog:
* sysdeps/s390/longjmp.c (longjmp, _longjmp, siglongjmp):
Don't create weak aliases,
because versioned symbols are created later.
* sysdeps/s390/s390-32/setjmp.S
(setjmp, _setjmp): Remove weak and rename to an unique name
in SHARED case due to existing versioned symbols.
* sysdeps/s390/s390-64/setjmp.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/getcontext.S
(getcontext): Create weak alias only in non SHARED case.
* sysdeps/unix/sysv/linux/s390/s390-64/getcontext.S: Likewise.
This patch provides optimized versions of strcmp and wcscmp with the z13
vector instructions.
The architecture specific string.h had a typo, which leads to ommiting the
inline version in this file if __USE_STRING_INLINES is defined.
Tested this inline version by tweaking test-strcmp.c.
ChangeLog:
* sysdeps/s390/multiarch/strcmp-vx.S: New File.
* sysdeps/s390/multiarch/strcmp.c: Likewise.
* sysdeps/s390/multiarch/wcscmp-c.c: Likewise.
* sysdeps/s390/multiarch/wcscmp-vx.S: Likewise.
* sysdeps/s390/multiarch/wcscmp.c: Likewise.
* sysdeps/s390/s390-32/multiarch/strcmp.c: Likewise.
* sysdeps/s390/s390-64/multiarch/strcmp.c: Likewise.
* sysdeps/s390/multiarch/Makefile (sysdep_routines): Add strcmp and
wcscmp functions.
* sysdeps/s390/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Add ifunc test for strcmp, wcscmp.
* string/strcmp.c (STRCMP): Define and use macro.
* benchtests/bench-wcscmp.c: New File.
* benchtests/Makefile (wcsmbs-bench): Add wcscmp.
* sysdeps/s390/bits/string.h: Fix typo: _HAVE_STRING_ARCH_strcmp
instead of _HAVE_STRING_ARCH_memchr.
On s390 all ifunc resolvers were implemented in multiarch/ifunc-resolve.c.
The resulting single object files has undefined references to all ifunc-functions.
This patch introduces one multiarch/<func>.c file for each of memcpy, memcmp
and memset with the function specific ifunc resolver. The different function
implementations are now implemented in multiarch/<func>-s390x.S
(moved from multiarch/<func>.S).
The new multiarch/ifunc-resolve.h file contains the ifunc-resolver macro
and other helper-macros. They are merged and are now used in common for
32/64bit. Therefore the __<func>_g5/__<func>_z900 functions were renamed to
__<func>_default.
This patch also enables testing the ifunc implementations by implementing
the function __libc_ifunc_impl_list. It uses the helper-macros of ifunc-resolve.h.
ChangeLog:
* sysdeps/s390/s390-32/multiarch/Makefile (sysdep_routines):
Remove ifunc-resolve, add memset-s390, memcpy-s390, memcmp-s390.
* sysdeps/s390/s390-32/multiarch/ifunc-resolve.c: Delete File.
* sysdeps/s390/s390-32/multiarch/memcmp.S: Move to ...
* sysdeps/s390/s390-32/multiarch/memcmp-s390.S: ... here.
(memcmp, bcmp): Use __memcmp_default as alias source.
* sysdeps/s390/s390-32/multiarch/memcmp.c: New File.
* sysdeps/s390/s390-32/memcmp.S (__memcmp_g5):
Rename to __memcmp_default.
* sysdeps/s390/s390-32/multiarch/memcpy.S: Move to ...
* sysdeps/s390/s390-32/multiarch/memcpy-s390.S: ... here.
(memcpy): Use __memcpy_default as alias source.
* sysdeps/s390/s390-32/multiarch/memcpy.c: New File.
* sysdeps/s390/s390-32/memcpy.S (__memcpy_g5):
Rename to __memcpy_default.
* sysdeps/s390/s390-32/multiarch/memset.S: Move to ...
* sysdeps/s390/s390-32/multiarch/memset-s390.S: ... here.
(memset): Use __memset_default as alias source.
* sysdeps/s390/s390-32/multiarch/memset.c: New File.
* sysdeps/s390/s390-32/memset.S (__memset_g5):
Rename to __memset_default.
* sysdeps/s390/s390-64/multiarch/Makefile (sysdep_routines):
Remove ifunc-resolve, add memset-s390x, memcpy-s390x, memcmp-s390x.
* sysdeps/s390/s390-64/multiarch/ifunc-resolve.c: Delete File.
* sysdeps/s390/s390-64/multiarch/memcmp.S: Move to ...
* sysdeps/s390/s390-64/multiarch/memcmp-s390x.S: ... here.
(memcmp, bcmp): Use __memcmp_default as alias source.
* sysdeps/s390/s390-64/multiarch/memcmp.c: New File.
* sysdeps/s390/s390-64/memcmp.S (__memcmp_z900):
Rename to __memcmp_default.
* sysdeps/s390/s390-64/multiarch/memcpy.S: Move to ...
* sysdeps/s390/s390-64/multiarch/memcpy-s390x.S: ... here.
(memcpy): Use __memcpy_default as alias source.
* sysdeps/s390/s390-64/multiarch/memcpy.c: New File.
* sysdeps/s390/s390-64/memcpy.S (__memcpy_z900):
Rename to __memcpy_default.
* sysdeps/s390/s390-64/multiarch/memset.S: Move to ...
* sysdeps/s390/s390-64/multiarch/memset-s390x.S: ... here.
(memset): Use __memset_default as alias source.
* sysdeps/s390/s390-64/multiarch/memset.c: New File.
* sysdeps/s390/s390-64/memset.S (__memset_z900):
Rename to __memset_default.
* sysdeps/s390/multiarch/ifunc-resolve.h: New File.
* sysdeps/s390/multiarch/ifunc-impl-list.c: New File.
