gas -mtune= may change NOP generating patterns but -mtune=i686 has no
difference from the default by inspecting .o and .os files.
Note: Clang doesn't support -Wa,-mtune=i686.
Remove redundant strcspn-generic, strpbrk-generic and strspn-generic
from sysdep_routines in sysdeps/x86_64/multiarch/Makefile added by
commit c69f960b01
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Sun Jul 3 21:28:07 2022 -0700
x86: Add support for building str{c|p}{brk|spn} with explicit ISA level
since they have been added to sysdep_routines in sysdeps/x86_64/Makefile.
This change adds tests for the mbrtoc8 and c8rtomb functions adopted for
C++20 via WG21 P0482R6 and for C2X via WG14 N2653, and for the char8_t
typedef adopted for C2X from WG14 N2653.
The tests for mbrtoc8 and c8rtomb specifically exercise conversion to
and from Big5-HKSCS because of special cases that arise with that encoding.
Big5-HKSCS defines some double byte sequences that convert to more than
one Unicode code point. In order to test this, the locale dependencies
for running tests under wcsmbs is expanded to include zh_HK.BIG5-HKSCS.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This change provides implementations for the mbrtoc8 and c8rtomb
functions adopted for C++20 via WG21 P0482R6 and for C2X via WG14
N2653. It also provides the char8_t typedef from WG14 N2653.
The mbrtoc8 and c8rtomb functions are declared in uchar.h in C2X
mode or when the _GNU_SOURCE macro or C++20 __cpp_char8_t feature
test macro is defined.
The char8_t typedef is declared in uchar.h in C2X mode or when the
_GNU_SOURCE macro is defined and the C++20 __cpp_char8_t feature
test macro is not defined (if __cpp_char8_t is defined, then char8_t
is a builtin type).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch corrects the Big5-HKSCS converter to preserve the lowest 3 bits of
the mbstate_t __count data member when the converter encounters an incomplete
multibyte character.
This fixes BZ #25744.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
We found that string functions were using AND+ADDP
to find the nibble/syndrome mask but there is an easier
opportunity through `SHRN dst.8b, src.8h, 4` (shift
right every 2 bytes by 4 and narrow to 1 byte) and has
same latency on all SIMD ARMv8 targets as ADDP. There
are also possible gaps for memcmp but that's for
another patch.
We see 10-20% savings for small-mid size cases (<=128)
which are primary cases for general workloads.
Since Linux 4.9, the kernel provides
/proc/sys/user/max_{mnt,pid,user}_namespace as a limitation of number of
namespaces. Some distros (for example, Slint Linux 14.2.1) set them (or
only max_user_namespace) to zero as a "security policy" for disabling
namespaces.
The clone() call will set errno to ENOSPC under such a limitation. We
didn't check ENOSPC in the code so the test will FAIL, and report:
unable to unshare user/fs: No space left on device
This message is, unfortunately, very unhelpful. It leads people to
check the memory or disk space, instead of finding the real issue.
To improve the situation, we should check for ENOSPC and return
UNSUPPORTED as the test result. Also refactor check_for_unshare_hints()
to emit a proper message telling people how to make the test work, if
they really need to run the namespaced tests.
Reported-by: Philippe Delavalade <philippe.delavalade@orange.fr>
URL: https://lists.linuxfromscratch.org/sympa/arc/lfs-support/2022-06/msg00022.html
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: DJ Delorie <dj@redhat.com>
1. Refactor files so that all implementations are in the multiarch
directory
- Moved the implementation portion of memcmp sse2 from memcmp.S to
multiarch/memcmp-sse2.S
- The non-multiarch file now only includes one of the
implementations in the multiarch directory based on the compiled
ISA level (only used for non-multiarch builds. Otherwise we go
through the ifunc selector).
2. Add ISA level build guards to different implementations.
- I.e memcmp-avx2-movsb.S which is ISA level 3 will only build if
compiled ISA level <= 3. Otherwise there is no reason to include
it as we will always use one of the ISA level 4
implementations (memcmp-evex-movbe.S).
3. Add new multiarch/rtld-{w}memcmp{eq}.S that just include the
non-multiarch {w}memcmp{eq}.S which will in turn select the best
implementation based on the compiled ISA level.
4. Refactor the ifunc selector and ifunc implementation list to use
the ISA level aware wrapper macros that allow functions below the
compiled ISA level (with a guranteed replacement) to be skipped.
Tested with and without multiarch on x86_64 for ISA levels:
{generic, x86-64-v2, x86-64-v3, x86-64-v4}
And m32 with and without multiarch.
1. Refactor files so that all implementations are in the multiarch
directory
- Moved the implementation portion of memset sse2 from memset.S to
multiarch/memset-sse2.S
- The non-multiarch file now only includes one of the
implementations in the multiarch directory based on the compiled
ISA level (only used for non-multiarch builds. Otherwise we go
through the ifunc selector).
2. Add ISA level build guards to different implementations.
- I.e memset-avx2-unaligned-erms.S which is ISA level 3 will only
build if compiled ISA level <= 3. Otherwise there is no reason
to include it as we will always use one of the ISA level 4
implementations (memset-evex-unaligned-erms.S).
3. Add new multiarch/rtld-memset.S that just include the
non-multiarch memset.S which will in turn select the best
implementation based on the compiled ISA level.
4. Refactor the ifunc selector and ifunc implementation list to use
the ISA level aware wrapper macros that allow functions below the
compiled ISA level (with a guranteed replacement) to be skipped.
Tested with and without multiarch on x86_64 for ISA levels:
{generic, x86-64-v2, x86-64-v3, x86-64-v4}
And m32 with and without multiarch.
1. Refactor files so that all implementations are in the multiarch
directory
- Moved the implementation portion of memmove sse2 from memmove.S
to multiarch/memmove-sse2.S
- The non-multiarch file now only includes one of the
implementations in the multiarch directory based on the compiled
ISA level (only used for non-multiarch builds. Otherwise we go
through the ifunc selector).
2. Add ISA level build guards to different implementations.
- I.e memmove-avx2-unaligned-erms.S which is ISA level 3 will only
build if compiled ISA level <= 3. Otherwise there is no reason
to include it as we will always use one of the ISA level 4
implementations (memmove-evex-unaligned-erms.S).
3. Add new multiarch/rtld-memmove.S that just include the
non-multiarch memmove.S which will in turn select the best
implementation based on the compiled ISA level.
4. Refactor the ifunc selector and ifunc implementation list to use
the ISA level aware wrapper macros that allow functions below the
compiled ISA level (with a guranteed replacement) to be skipped.
Tested with and without multiarch on x86_64 for ISA levels:
{generic, x86-64-v2, x86-64-v3, x86-64-v4}
And m32 with and without multiarch.
isa raising memmove
The changes for these functions are different than the others because
the best implementation (sse4_2) requires the generic
implementation as a fallback to be built as well.
Changes are:
1. Add non-multiarch functions for str{c|p}{brk|spn}.c to statically
select the best implementation based on the configured ISA build
level.
2. Add stubs for str{c|p}{brk|spn}-generic and varshift.c to in the
sysdeps/x86_64 directory so that the the sse4 implementation will
have all of its dependencies for the non-multiarch / rtld build
when ISA level >= 2.
3. Add new multiarch/rtld-strcspn.c that just include the
non-multiarch strcspn.c which will in turn select the best
implementation based on the compiled ISA level.
4. Refactor the ifunc selector and ifunc implementation list to use
the ISA level aware wrapper macros that allow functions below the
compiled ISA level (with a guranteed replacement) to be skipped.
Tested with and without multiarch on x86_64 for ISA levels:
{generic, x86-64-v2, x86-64-v3, x86-64-v4}
And m32 with and without multiarch.
And also fixes the SINGLE_THREAD_P macro for SINGLE_THREAD_BY_GLOBAL,
since header inclusion single-thread.h is in the wrong order, the define
needs to come before including sysdeps/unix/sysdep.h. The macro
is now moved to a per-arch single-threade.h header.
The SINGLE_THREAD_P is used on some more places.
Checked on aarch64-linux-gnu and x86_64-linux-gnu.
It was added on Linux 5.12 (2a1867219c7b27f928e2545782b86daaf9ad50bd)
to allow change the properties of a mount or a mount tree using file
descriptors which the new mount api is based on.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The new mount API was added on Linux 5.2 with six new syscalls:
fsopen, fsconfig, fsmount, move_mount, fspick, and open_tree.
The new test verifies minimal functionality along with error paths
for specific arguments and their corner cases.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
It was added on Linux 5.2 (a07b20004793d8926f78d63eb5980559f7813404)
to return a O_PATH-opened file descriptor to an existing mountpoint.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
It was added on Linux 5.2 (cf3cba4a429be43e5527a3f78859b1bfd9ebc5fb)
that can be used to pick an existing mountpoint into an filesystem
context which can thereafter be used to reconfigure a superblock
with fsconfig syscall.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
It was added on Linux 5.2 (ecdab150fddb42fe6a739335257949220033b782)
as a way to a configure filesystem creation context and trigger
actions upon it, to be used in conjunction with fsopen, fspick and
fsmount.
The fsconfig_command commands are currently only defined as an enum,
so they can't be checked on tst-mount-consts.py with current test
support.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The AFP feature (Alternate floating-point behavior) was added in armv8.7 and
introduced new FPCR bits.
Currently, HWCAP2_AFP bits (bit 0, 1, 2) in FPCR are preserved when fenv is
set to default environment. This is a deviation from standard behaviour.
Clear these bits when setting the fenv to default.
There is no libc API to modify the new FPCR bits. Restoring those bits matters
if the user changed them directly.
NODELETE status is propagated from the referencing object to the
referenced object, not the other way round. The code is correct, only
the log message has the wrong direction.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
In-band signaling avoids an uninitialized variable warning when
building with -Og and GCC 12.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Move the buffer management from realpath_stk to __realpath. This
allows returning directly after allocation errors.
Always make a copy of the result buffer using strdup even if it is
already heap-allocated. (Heap-allocated buffers are somewhat rare.)
This avoids GCC warnings at certain optimization levels.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Previously, they were assumed to be in ISO-8859-1, and that the output
charset overlapped with ISO-8859-1 for the characters actually used.
However, this did not work as intended on many architectures even for
an ISO-8859-1 output encoding because of the char signedness bug in
lr_getc. Therefore, this commit switches to UTF-8 without making
provisions for backwards compatibility.
The following Elisp code can be used to convert locale definition files
to UTF-8:
(defun glibc/convert-localedef (from to)
(interactive "r")
(save-excursion
(save-restriction
(narrow-to-region from to)
(goto-char (point-min))
(save-match-data
(while (re-search-forward "<U\\([0-9a-fA-F]+\\)>" nil t)
(let* ((codepoint (string-to-number (match-string 1) 16))
(converted
(cond
((memq codepoint '(?/ ?\ ?< ?>))
(string ?/ codepoint))
((= codepoint ?\") "<U0022>")
(t (string codepoint)))))
(replace-match converted t)))))))
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This will permit reusing the Unicode character processing for
different character encodings, not just the current <U...> encoding.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The array lr->buf contains characters, which can be signed. A 0xff
byte in the input could be incorrectly reported as EOF. More
importantly, get_string in linereader.c converts a signed input byte
to a Unicode code point using ADDWC ((uint32_t) ch), under the
assumption that this decodes the ISO-8859-1 input encoding. If char
is signed, this does not give the correct result. This means that
ISO-8859-1 input files for localedef are not actually supported,
contrary to the comment in get_string. This is a happy accident because
we can therefore change the file encoding to UTF-8 without impacting
backwards compatibility.
While at it, remove the \32 check for MS-DOS end-of-file character (^Z).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And introduce struct lr_buffer. The functions addc and adds can
be called from functions, enabling subsequent refactoring.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Beside weak_hidden_alias/declare_symbol_alias/hidden_data_ver, many
*_hidden_* macros are removed. If there is a rare need to use one, one
may write something like `#if IS_IN (libm)\nhidden_def (...)\n#endif`
instead.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The main drive is to optimize the internal usage and required size
when sigset_t is embedded in other data structures. On Linux, the
current supported signal set requires up to 8 bytes (16 on mips),
was lower than the user defined sigset_t (128 bytes).
A new internal type internal_sigset_t is added, along with the
functions to operate on it similar to the ones for sigset_t. The
internal-signals.h is also refactored to remove unused functions
Besides small stack usage on some functions (posix_spawn, abort)
it lower the struct pthread by about 120 bytes (112 on mips).
Checked on x86_64-linux-gnu.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
The new asymmetric mode is available when HWCAP2_MTE3 is set (support is
available), bit2 is set in the tunable (user request per application),
and the system is configured such that the asymmetric mode is preferred over
sync or async (per-cpu system-wide setting).
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
On success, mq_receive() and mq_timedreceive() return the number of
bytes in the received message, so it requires to check if the value
is larger than 0.
Checked on i686-linux-gnu.
Was missing to for the multiarch build rtld-strncmp-sse4_2.os was
being built and exporting symbols:
build/glibc/string/rtld-strncmp-sse4_2.os:
0000000000000000 T __strncmp_sse42
Introduced in:
commit 11ffcacb64
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Wed Jun 21 12:10:50 2017 -0700
x86-64: Implement strcmp family IFUNC selectors in C
Was missing to for the multiarch build rtld-strcspn-sse4.os was
being built and exporting symbols:
build/glibc/string/rtld-strcspn-sse4.os:
U ___m128i_shift_right
U __strcspn_generic
0000000000000000 T __strcspn_sse42
U strlen
build/glibc/string/rtld-varshift.os:
0000000000000000 R ___m128i_shift_right
Introduced in:
commit 06e51c8f3d
Author: H.J. Lu <hongjiu.lu@intel.com>
Date: Fri Jul 3 02:48:56 2009 -0700
Add SSE4.2 support for strcspn, strpbrk, and strspn on x86-64.
Was missing to for the multiarch build rtld-memmove-ssse3.os was
being built and exporting symbols:
>$ nm string/rtld-memmove-ssse3.os
U __GI___chk_fail
0000000000000020 T __memcpy_chk_ssse3
0000000000000040 T __memcpy_ssse3
0000000000000020 T __memmove_chk_ssse3
0000000000000040 T __memmove_ssse3
0000000000000000 T __mempcpy_chk_ssse3
0000000000000010 T __mempcpy_ssse3
U __x86_shared_cache_size_half
Introduced after 2.35 in:
commit 26b2478322
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Thu Apr 14 11:47:40 2022 -0500
x86: Reduce code size of mem{move|pcpy|cpy}-ssse3
1. Remove sse2 instructions when using the avx512 or avx version.
2. Fixup some format nits in how the address offsets where aligned.
3. Use more space efficient instructions in the conditional AVX
restoral.
- vpcmpeqq -> vpcmpeqb
- cmp imm32, r; jz -> inc r; jz
4. Use `rep movsb` instead of `rep movsq`. The former is guranteed to
be fast with the ERMS flags, the latter is not. The latter also
wastes an instruction in size setup.
The primary memmove_{impl}_unaligned_erms implementations don't
interact with this function. Putting them in same file both
wastes space and unnecessarily bloats a hot code section.
Implementation wise:
1. Remove the VZEROUPPER as memset_{impl}_unaligned_erms does not
use the L(stosb) label that was previously defined.
2. Don't give the hotpath (fallthrough) to zero size.
Code positioning wise:
Move memset_{chk}_erms to its own file. Leaving it in between the
memset_{impl}_unaligned both adds unnecessary complexity to the
file and wastes space in a relatively hot cache section.
These files simply include the sysdeps/posix implementations which would
be used even in the absence of the files. They have been unnecessary
since 7b17aeda0c when nice and signal were removed from the
syscalls.list file.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This maintains compatibility between <sys/mman.h> and <linux/uio.h>.
Before that, the addition of process_madvise made those two header
files incompatible. This has been observed resulting in a build
failure in LLDB's Process/Linux/NativeRegisterContextLinux_s390x.cpp
source file.
Fixes commit d19ee3473d
("linux: Add process_madvise").
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
