Florian Weimer [Thu, 9 Dec 2021 16:57:11 +0000 (17:57 +0100)]
Remove TLS_TCB_ALIGN and TLS_INIT_TCB_ALIGN
TLS_INIT_TCB_ALIGN is not actually used. TLS_TCB_ALIGN was likely
introduced to support a configuration where the thread pointer
has not the same alignment as THREAD_SELF. Only ia64 seems to use
that, but for the stack/pointer guard, not for storing tcbhead_t.
Some ports use TLS_TCB_OFFSET and TLS_PRE_TCB_SIZE to shift
the thread pointer, potentially landing in a different residue class
modulo the alignment, but the changes should not impact that.
In general, given that TLS variables have their own alignment
requirements, having different alignment for the (unshifted) thread
pointer and struct pthread would potentially result in dynamic
offsets, leading to more complexity.
hppa had different values before: __alignof__ (tcbhead_t), which
seems to be 4, and __alignof__ (struct pthread), which was 8
(old default) and is now 32. However, it defines THREAD_SELF as:
/* Return the thread descriptor for the current thread. */
# define THREAD_SELF \
({ struct pthread *__self; \
__self = __get_cr27(); \
__self - 1; \
})
So the thread pointer points after struct pthread (hence __self - 1),
and they have to have the same alignment on hppa as well.
Similarly, on ia64, the definitions were different. We have:
And TLS_PRE_TCB_SIZE is a multiple of the struct pthread alignment
(confirmed by the new _Static_assert in sysdeps/ia64/libc-tls.c).
On m68k, we have a larger gap between tcbhead_t and struct pthread.
But as far as I can tell, the port is fine with that. The definition
of TCB_OFFSET is sufficient to handle the shifted TCB scenario.
Florian Weimer [Thu, 9 Dec 2021 08:49:32 +0000 (09:49 +0100)]
nptl: Add public rseq symbols and <sys/rseq.h>
The relationship between the thread pointer and the rseq area
is made explicit. The constant offset can be used by JIT compilers
to optimize rseq access (e.g., for really fast sched_getcpu).
Extensibility is provided through __rseq_size and __rseq_flags.
(In the future, the kernel could request a different rseq size
via the auxiliary vector.)
Co-Authored-By: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Florian Weimer [Thu, 9 Dec 2021 08:49:32 +0000 (09:49 +0100)]
nptl: Add rseq registration
The rseq area is placed directly into struct pthread. rseq
registration failure is not treated as an error, so it is possible
that threads run with inconsistent registration status.
<sys/rseq.h> is not yet installed as a public header.
Add tests that had src/dst non 4-byte aligned. Since src/dst are
initialized/compared as uint32_t type which is 4-byte aligned this can
break on some targets.
Fix the issue by specifying a new non-aligned 4-byte
`unaligned_uint32_t` for src/dst.
Another alternative is to rely on memcpy/memcmp for
initializing/testing src/dst. Using memcpy for initializing in memcpy
tests, however, could lead to future bugs.
This patch improves the user experience by looking at the magic value,
which is always written, but never checked. It should still be possible
to trigger a segmentation fault with crafted files, but this already
catch many cases.
Florian Weimer [Mon, 6 Dec 2021 07:01:08 +0000 (08:01 +0100)]
misc, nptl: Remove stray references to __condvar_load_64_relaxed
The function was renamed to __atomic_wide_counter_load_relaxed
in commit 8bd336a00a5311bf7a9e99b3b0e9f01ff5faa74b ("nptl: Extract
<bits/atomic_wide_counter.h> from pthread_cond_common.c").
Florian Weimer [Sun, 5 Dec 2021 12:50:17 +0000 (13:50 +0100)]
csu: Always use __executable_start in gmon-start.c
Current binutils defines __executable_start as the lowest text
address, so using the entry point address as a fallback is no
longer necessary. As a result, overriding <entry.h> is only
necessary if the entry point is not called _start.
The previous approach to define __ASSEMBLY__ to suppress the
declaration breaks if headers included by <entry.h> are not
compatible with __ASSEMBLY__. This happens with rseq integration
because it is necessary to include kernel headers in more places.
Florian Weimer [Sun, 5 Dec 2021 10:28:34 +0000 (11:28 +0100)]
elf: execve statically linked programs instead of crashing [BZ #28648]
Programs without dynamic dependencies and without a program
interpreter are now run via execve.
Previously, the dynamic linker either crashed while attempting to
read a non-existing dynamic segment (looking for DT_AUDIT/DT_DEPAUDIT
data), or the self-relocated in the static PIE executable crashed
because the outer dynamic linker had already applied RELRO protection.
<dl-execve.h> is needed because execve is not available in the
dynamic loader on Hurd.
H.J. Lu [Sat, 4 Dec 2021 19:25:53 +0000 (11:25 -0800)]
Add --with-timeoutfactor=NUM to specify TIMEOUTFACTOR
On Ice Lake and Tiger Lake laptops, some test programs timeout when there
are 3 "make check -j8" runs in parallel. Add --with-timeoutfactor=NUM to
specify an integer to scale the timeout of test programs, which can be
overriden by TIMEOUTFACTOR environment variable.
Noah Goldstein [Fri, 3 Dec 2021 23:29:25 +0000 (15:29 -0800)]
x86-64: Use notl in EVEX strcmp [BZ #28646]
Must use notl %edi here as lower bits are for CHAR comparisons
potentially out of range thus can be 0 without indicating mismatch.
This fixes BZ #28646.
Wilco Dijkstra [Thu, 2 Dec 2021 18:33:26 +0000 (18:33 +0000)]
AArch64: Improve A64FX memcpy
v2 is a complete rewrite of the A64FX memcpy. Performance is improved
by streamlining the code, aligning all large copies and using a single
unrolled loop for all sizes. The code size for memcpy and memmove goes
down from 1796 bytes to 868 bytes. Performance is better in all cases:
bench-memcpy-random is 2.3% faster overall, bench-memcpy-large is ~33%
faster for large sizes, bench-memcpy-walk is 25% faster for small sizes
and 20% for the largest sizes. The geomean of all tests in bench-memcpy
is 5.1% faster, and total time is reduced by 4%.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Wilco Dijkstra [Thu, 2 Dec 2021 18:30:55 +0000 (18:30 +0000)]
AArch64: Optimize memcmp
Rewrite memcmp to improve performance. On small and medium inputs performance
is 10-20% better. Large inputs use a SIMD loop processing 64 bytes per
iteration, which is 30-50% faster depending on the size.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Matheus Castanho [Tue, 26 Oct 2021 13:44:59 +0000 (10:44 -0300)]
powerpc64[le]: Fix CFI and LR save address for asm syscalls [BZ #28532]
Syscalls based on the assembly templates are missing CFI for r31, which gets
clobbered when scv is used, and info for LR is inaccurate, placed in the wrong
LOC and not using the proper offset. LR was also being saved to the callee's
frame, while the ABI mandates it to be saved to the caller's frame. These are
fixed by this commit.
The syscall pipe2 was added in linux 2.6.27 and glibc requires linux
3.2.0. The patch removes the arch-specific implementation for alpha,
ia64, mips, sh, and sparc which requires a different kernel ABI
than the usual one.
Checked on x86_64-linux-gnu and with a build for the affected ABIs.
Variadic function calls in syscalls.list does not work for all ABIs
(for instance where the argument are passed on the stack instead of
registers) and might have underlying issues depending of the variadic
type (for instance if a 64-bit argument is used).
The LFS prlimit64 requires a arch-specific implementation in
syscalls.list. Instead add a generic one that handles the
required symbol alias for __RLIM_T_MATCHES_RLIM64_T.
HPPA is the only outlier which requires a different default
symbol.
Checked on x86_64-linux-gnu and with build for the affected ABIs.
Passing 64-bit arguments on syscalls.list is tricky: it requires
to reimplement the expected kernel abi in each architecture. This
is way to better to represent in C code where we already have
macros for this (SYSCALL_LL64).
Paul Eggert [Wed, 24 Nov 2021 22:16:09 +0000 (14:16 -0800)]
regex: fix buffer read overrun in search [BZ#28470]
Problem reported by Benno Schulenberg in:
https://lists.gnu.org/r/bug-gnulib/2021-10/msg00035.html
* posix/regexec.c (re_search_internal): Use better bounds check.
Sunil K Pandey [Sat, 6 Nov 2021 06:29:02 +0000 (23:29 -0700)]
x86-64: Add vector sin/sinf to libmvec microbenchmark
Add vector sin/sinf and input files to libmvec microbenchmark.
libmvec-sin-inputs:
90% Normal random distribution
range: (-DBL_MAX, DBL_MAX)
mean: 0.0
sigma: 5.0
10% uniform random distribution in range (-1000.0, 1000.0)
libmvec-sinf-inputs:
90% Normal random distribution
range: (-FLT_MAX, FLT_MAX)
mean: 0.0f
sigma: 5.0f
10% uniform random distribution in range (-1000.0f, 1000.0f)
Sunil K Pandey [Sat, 6 Nov 2021 06:19:53 +0000 (23:19 -0700)]
x86-64: Add vector pow/powf to libmvec microbenchmark
Add vector pow/powf and input files to libmvec microbenchmark.
libmvec-pow-inputs:
arg1:
90% Normal random distribution
range: (0.0, 256.0)
mean: 0.0
sigma: 32.0
10% uniform random distribution in range (0.0, 256.0)
arg2:
90% Normal random distribution
range: (-127.0, 127.0)
mean: 0.0
sigma: 16.0
10% uniform random distribution in range (-127.0, 127.0)
libmvec-powf-inputs:
arg1:
90% Normal random distribution
range: (0.0f, 100.0f)
mean: 0.0f
sigma: 16.0f
10% uniform random distribution in range (0.0f, 100.0f)
arg2:
90% Normal random distribution
range: (-10.0f, 10.0f)
mean: 0.0f
sigma: 8.0f
10% uniform random distribution in range (-10.0f, 10.0f)
Sunil K Pandey [Sat, 6 Nov 2021 06:15:20 +0000 (23:15 -0700)]
x86-64: Add vector log/logf to libmvec microbenchmark
Add vector log/logf and input files to libmvec microbenchmark.
libmvec-log-inputs:
70% Normal random distribution
range: (0.0, DBL_MAX)
mean: 1.0
sigma: 50.0
30% uniform random distribution in range (0.0, DBL_MAX)
libmvec-logf-inputs:
70% Normal random distribution
range: (0.0f, FLT_MAX)
mean: 1.0f
sigma: 50.0f
30% uniform random distribution in range (0.0f, FLT_MAX)
Sunil K Pandey [Sat, 6 Nov 2021 06:11:00 +0000 (23:11 -0700)]
x86-64: Add vector exp/expf to libmvec microbenchmark
Add vector exp/expf and input files to libmvec microbenchmark.
libmvec-exp-inputs:
90% Normal random distribution
range: (-708.0, 709.0)
mean: 0.0
sigma: 16.0
10% uniform random distribution in range (-500.0, 500.0)
libmvec-expf-inputs:
90% Normal random distribution
range: (-87.0f, 88.0f)
mean: 0.0f
sigma: 8.0f
10% uniform random distribution in range (-50.0f, 50.0f)
Sunil K Pandey [Fri, 5 Nov 2021 20:44:49 +0000 (13:44 -0700)]
x86-64: Add vector cos/cosf to libmvec microbenchmark
Add vector cos/cosf and input files to libmvec microbenchmark.
libmvec-cos-inputs:
90% Normal random distribution
range: (-DBL_MAX, DBL_MAX)
mean: 0.0
sigma: 5.0
10% uniform random distribution in range (-1000.0, 1000.0)
libmvec-cosf-inputs:
90% Normal random distribution
range: (-FLT_MAX, FLT_MAX)
mean: 0.0f
sigma: 5.0f
10% uniform random distribution in range (-1000.0f, 1000.0f)
Now that Hurd implementis both close_range and closefrom (f2c996597d),
we can make close_range() a base ABI, and make the default closefrom()
implementation on top of close_range().
The generic closefrom() implementation based on __getdtablesize() is
moved to generic close_range(). On Linux it will be overriden by
the auto-generation syscall while on Hurd it will be a system specific
implementation.
The closefrom() now calls close_range() and __closefrom_fallback().
Since on Hurd close_range() does not fail, __closefrom_fallback() is an
empty static inline function set by__ASSUME_CLOSE_RANGE.
The __ASSUME_CLOSE_RANGE also allows optimize Linux
__closefrom_fallback() implementation when --enable-kernel=5.9 or
higher is used.
Finally the Linux specific tst-close_range.c is moved to io and
enabled as default. The Linuxism and CLOSE_RANGE_UNSHARE are
guarded so it can be built for Hurd (I have not actually test it).
Checked on x86_64-linux-gnu, i686-linux-gnu, and with a i686-gnu
build.
Florian Weimer [Wed, 24 Nov 2021 07:59:54 +0000 (08:59 +0100)]
nptl: Do not set signal mask on second setjmp return [BZ #28607]
__libc_signal_restore_set was in the wrong place: It also ran
when setjmp returned the second time (after pthread_exit or
pthread_cancel). This is observable with blocked pending
signals during thread exit.
powerpc: Define USE_PPC64_NOTOC iff compiler supports it
The @notoc usage only yields an advantage on ISA 3.1+ machine (power10)
and for ld.bfd also when it sees pcrel relocations used on the code
(generated if compiler targets ISA 3.1+). On bfd case ISA 3.1+
instruction on stubs are used iff linker also sees the new pc-relative
relocations (for instance R_PPC64_D34), otherwise it generates default
stubs (ppc64_elf_check_relocs:4700).
This patch also help on linkers that do not implement this optimization,
since building for older ISA (such as 3.0 / power9) will also trigger
power10 stubs generation in the assembly code uses the NOTOC imacro.
Checked on powerpc64le-linux-gnu.
Reviewed-by: Fangrui Song <maskray@google.com> Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
setjmp: Replace jmp_buf-macros.h with jmp_buf-macros.sym
It requires less boilerplate code for newer ports. The _Static_assert
checks from internal setjmp are moved to its own internal test since
setjmp.h is included early by multiple headers (to generate
rtld-sizes.sym).
The riscv jmp_buf-macros.h check is also redundant, it is already
done by riscv configure.ac.
Checked with a build for the affected architectures.
Joseph Myers [Mon, 22 Nov 2021 15:30:12 +0000 (15:30 +0000)]
Update kernel version to 5.15 in tst-mman-consts.py
This patch updates the kernel version in the test tst-mman-consts.py
to 5.15. (There are no new MAP_* constants covered by this test in
5.15 that need any other header changes.)
Stafford Horne [Wed, 13 Oct 2021 10:43:30 +0000 (19:43 +0900)]
malloc: Fix malloc debug for 2.35 onwards
The change 1e5a5866cb ("Remove malloc hooks [BZ #23328]") has broken
ports that are using GLIBC_2_35, like the new OpenRISC port I am working
on.
The libc_malloc_debug.so library used to bring in the debug
infrastructure is currently essentially empty for GLIBC_2_35 ports like
mine causing mtrace tests to fail:
Florian Weimer [Wed, 17 Nov 2021 11:20:13 +0000 (12:20 +0100)]
nptl: Extract <bits/atomic_wide_counter.h> from pthread_cond_common.c
And make it an installed header. This addresses a few aliasing
violations (which do not seem to result in miscompilation due to
the use of atomics), and also enables use of wide counters in other
parts of the library.
The debug output in nptl/tst-cond22 has been adjusted to print
the 32-bit values instead because it avoids a big-endian/little-endian
difference.
Sunil K Pandey [Fri, 5 Nov 2021 07:56:47 +0000 (00:56 -0700)]
x86-64: Create microbenchmark infrastructure for libmvec
Add python script to generate libmvec microbenchmark from the input
values for each libmvec function using skeleton benchmark template.
Creates double and float benchmarks with vector length 1, 2, 4, 8,
and 16 for each libmvec function. Vector length 1 corresponds to
scalar version of function and is included for vector function perf
comparison.
Co-authored-by: Haochen Jiang <haochen.jiang@intel.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
elf: hidden visibility for __minimal_malloc functions
Since b05fae4d8e34, __minimal malloc code is used during static
startup before PIE self-relocation (_dl_relocate_static_pie).
So it requires the same fix done for other objects by 47618209d05a.
Checked on aarch64, x86_64, and i686 with and without static-pie.
H.J. Lu [Tue, 16 Nov 2021 00:28:39 +0000 (16:28 -0800)]
elf: Use a temporary file to generate Makefile fragments [BZ #28550]
1. Use a temporary file to generate Makefile fragments for DSO sorting
tests and use -include on them.
2. Add Makefile fragments to postclean-generated so that a "make clean"
removes the autogenerated fragments and a subsequent "make" regenerates
them.
tst-tzset: output reason when creating 4GiB file fails
Currently, if the temporary file creation fails the create_tz_file
function returns NULL. The NULL pointer is then passed to setenv which
causes a SIGSEGV. Rather than failing with a SIGSEGV print a warning
and exit.
H.J. Lu [Wed, 3 Nov 2021 01:33:07 +0000 (18:33 -0700)]
Add LLL_MUTEX_READ_LOCK [BZ #28537]
CAS instruction is expensive. From the x86 CPU's point of view, getting
a cache line for writing is more expensive than reading. See Appendix
A.2 Spinlock in:
Noah Goldstein [Wed, 10 Nov 2021 22:16:25 +0000 (16:16 -0600)]
String: Split memcpy tests so that parallel build is faster
No bug.
This commit splits test-memcpy.c into test-memcpy.c and
test-memcpy-large.c. The idea is parallel builds will be able to run
both in parallel speeding up the process.
Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Noah Goldstein [Wed, 10 Nov 2021 22:18:56 +0000 (16:18 -0600)]
x86: Shrink memcmp-sse4.S code size
No bug.
This implementation refactors memcmp-sse4.S primarily with minimizing
code size in mind. It does this by removing the lookup table logic and
removing the unrolled check from (256, 512] bytes.
The current memcmp-sse4.S implementation has a large code size
cost. This has serious adverse affects on the ICache / ITLB. While
in micro-benchmarks the implementations appears fast, traces of
real-world code have shown that the speed in micro benchmarks does not
translate when the ICache/ITLB are not primed, and that the cost
of the code size has measurable negative affects on overall
application performance.
See https://research.google/pubs/pub48320/ for more details.
Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Joseph Myers [Wed, 10 Nov 2021 15:52:21 +0000 (15:52 +0000)]
Support C2X printf %b, %B
C2X adds a printf %b format (see
<http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2630.pdf>, accepted
for C2X), for outputting integers in binary. It also has recommended
practice for a corresponding %B format (like %b, but %#B starts the
output with 0B instead of 0b). Add support for these formats to
glibc.
One existing test uses %b as an example of an unknown format, to test
how glibc printf handles unknown formats; change that to %v. Use of
%b and %B as user-registered format specifiers continues to work (and
we already have a test that covers that, tst-printfsz.c).
Note that C2X also has scanf %b support, plus support for binary
constants starting 0b in strtol (base 0 and 2) and scanf %i (strtol
base 0 and scanf %i coming from a previous paper that added binary
integer literals). I intend to implement those features in a separate
patch or patches; as discussed in the thread starting at
<https://sourceware.org/pipermail/libc-alpha/2020-December/120414.html>,
they will be more complicated because they involve adding extra public
symbols to ensure compatibility with existing code that might not
expect 0b constants to be handled by strtol base 0 and 2 and scanf %i,
whereas simply adding a new format specifier poses no such
compatibility concerns.
Note that the actual conversion from integer to string uses existing
code in _itoa.c. That code has special cases for bases 8, 10 and 16,
probably so that the compiler can optimize division by an integer
constant in the code for those bases. If desired such special cases
could easily be added for base 2 as well, but that would be an
optimization, not actually needed for these printf formats to work.
Tested for x86_64 and x86. Also tested with build-many-glibcs.py for
aarch64-linux-gnu with GCC mainline to make sure that the test does
indeed build with GCC 12 (where format checking warnings are enabled
for most of the test).
Joseph Myers [Wed, 10 Nov 2021 15:21:19 +0000 (15:21 +0000)]
Update syscall lists for Linux 5.15
Linux 5.15 has one new syscall, process_mrelease (and also enables the
clone3 syscall for RV32). It also has a macro __NR_SYSCALL_MASK for
Arm, which is not a syscall but matches the pattern used for syscall
macro names.
Add __NR_SYSCALL_MASK to the names filtered out in the code dealing
with syscall lists, update syscall-names.list for the new syscall and
regenerate the arch-syscall.h headers with build-many-glibcs.py
update-syscalls.
The rtld_malloc functions are moved to its own file so it can be
used on csu code. Also, the functiosn are renamed to __minimal_*
(since there are now used not only on loader code).
Using the __minimal_malloc on tunables_strdup() avoids potential
issues with sbrk() calls while processing the tunables (I see
sporadic elf/tst-dso-ordering9 on powerpc64le with different
tests failing due ASLR).
Also, using __minimal_malloc over plain mmap optimizes the memory
allocation on both static and dynamic case (since it will any unused
space in either the last page of data segments, avoiding mmap() call,
or from the previous mmap() call).
Checked on x86_64-linux-gnu, i686-linux-gnu, and powerpc64le-linux-gnu.
Joseph Myers [Mon, 8 Nov 2021 19:11:51 +0000 (19:11 +0000)]
Fix memmove call in vfprintf-internal.c:group_number
A recent GCC mainline change introduces errors of the form:
vfprintf-internal.c: In function 'group_number':
vfprintf-internal.c:2093:15: error: 'memmove' specified bound between 9223372036854775808 and 18446744073709551615 exceeds maximum object size 9223372036854775807 [-Werror=stringop-overflow=]
2093 | memmove (w, s, (front_ptr -s) * sizeof (CHAR_T));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This is a genuine bug in the glibc code: s > front_ptr is always true
at this point in the code, and the intent is clearly for the
subtraction to be the other way round. The other arguments to the
memmove call here also appear to be wrong; w and s point just *after*
the destination and source for copying the rest of the number, so the
size needs to be subtracted to get appropriate pointers for the
copying. Adjust the memmove call to conform to the apparent intent of
the code, so fixing the -Wstringop-overflow error.
Now, if the original code were ever executed, a buffer overrun would
result. However, I believe this code (introduced in commit edc1686af0c0fc2eb535f1d38cdf63c1a5a03675, "vfprintf: Reuse work_buffer
in group_number", so in glibc 2.26) is unreachable in prior glibc
releases (so there is no need for a bug in Bugzilla, no need to
consider any backports unless someone wants to build older glibc
releases with GCC 12 and no possibility of this buffer overrun
resulting in a security issue).
work_buffer is 1000 bytes / 250 wide characters. This case is only
reachable if an initial part of the number, plus a grouped copy of the
rest of the number, fail to fit in that space; that is, if the grouped
number fails to fit in the space. In the wide character case,
grouping is always one wide character, so even with a locale (of which
there aren't any in glibc) grouping every digit, a number would need
to occupy at least 125 wide characters to overflow, and a 64-bit
integer occupies at most 23 characters in octal including a leading 0.
In the narrow character case, the multibyte encoding of the grouping
separator would need to be at least 42 bytes to overflow, again
supposing grouping every digit, but MB_LEN_MAX is 16. So even if we
admit the case of artificially constructed locales not shipped with
glibc, given that such a locale would need to use one of the character
sets supported by glibc, this code cannot be reached at present. (And
POSIX only actually specifies the ' flag for grouping for decimal
output, though glibc acts on it for other bases as well.)
With binary output (if you consider use of grouping there to be
valid), you'd need a 15-byte multibyte character for overflow; I don't
know if any supported character set has such a character (if, again,
we admit constructed locales using grouping every digit and a grouping
separator chosen to have a multibyte encoding as long as possible, as
well as accepting use of grouping with binary), but given that we have
this code at all (clearly it's not *correct*, or in accordance with
the principle of avoiding arbitrary limits, to skip grouping on
running out of internal space like that), I don't think it should need
any further changes for binary printf support to go in.
On the other hand, support for large sizes of _BitInt in printf (see
the N2858 proposal) *would* require something to be done about such
arbitrary limits (presumably using dynamic allocation in printf again,
for sufficiently large _BitInt arguments only - currently only
floating-point uses dynamic allocation, and, as previously discussed,
that could actually be replaced by bounded allocation given smarter
code).
Tested with build-many-glibcs.py for aarch64-linux-gnu (GCC mainline).
Also tested natively for x86_64.
This commit updates the memcpy tests to test both dst > src and dst <
src. This is because there is logic in the code based on the
Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
significantly increased the number of tests. On Intel Core i7-1165G7,
test-memcpy takes 120 seconds to run when machine is idle. Double
TIMEOUT to (8 * 60) for test-memcpy to avoid timeout when machine is
under heavy load.
Sergey Bugaev [Sat, 6 Nov 2021 15:35:24 +0000 (18:35 +0300)]
hurd: Implement close_range and closefrom
The close_range () function implements the same API as the Linux and
FreeBSD syscalls. It operates atomically and reliably. The specified
upper bound is clamped to the actual size of the file descriptor table;
it is expected that the most common use case is with last = UINT_MAX.
Like in the Linux syscall, it is also possible to pass the
CLOSE_RANGE_CLOEXEC flag to mark the file descriptors in the range
cloexec instead of acually closing them.
Also, add a Hurd version of the closefrom () function. Since unlike on
Linux, close_range () cannot fail due to being unuspported by the
running kernel, a fallback implementation is never necessary.
Noah Goldstein [Mon, 1 Nov 2021 05:49:52 +0000 (00:49 -0500)]
x86: Double size of ERMS rep_movsb_threshold in dl-cacheinfo.h
No bug.
This patch doubles the rep_movsb_threshold when using ERMS. Based on
benchmarks the vector copy loop, especially now that it handles 4k
aliasing, is better for these medium ranged.
Noah Goldstein [Mon, 1 Nov 2021 05:49:49 +0000 (00:49 -0500)]
benchtests: Add additional cases to bench-memcpy.c and bench-memmove.c
This commit adds more benchmarks for the common memcpy/memmove
benchmarks. The most signifcant cases are the half page offsets. The
current versions leaves dst and src near page aligned which leads to
false 4k aliasing on x86_64. This can add noise due to false
dependencies from one run to the next. As well, this seems like more
of an edge case that common case so it shouldn't be the only thing
Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Florian Weimer [Fri, 5 Nov 2021 16:01:24 +0000 (17:01 +0100)]
elf: Earlier missing dynamic segment check in _dl_map_object_from_fd
Separated debuginfo files have PT_DYNAMIC with p_filesz == 0. We
need to check for that before the _dl_map_segments call because
that could attempt to write to mappings that extend beyond the end
of the file, resulting in SIGBUS.
Nikita Popov [Tue, 2 Nov 2021 08:21:42 +0000 (13:21 +0500)]
gconv: Do not emit spurious NUL character in ISO-2022-JP-3 (bug 28524)
Bugfix 27256 has introduced another issue:
In conversion from ISO-2022-JP-3 encoding, it is possible
to force iconv to emit extra NUL character on internal state reset.
To do this, it is sufficient to feed iconv with escape sequence
which switches active character set.
The simplified check 'data->__statep->__count != ASCII_set'
introduced by the aforementioned bugfix picks that case and
behaves as if '\0' character has been queued thus emitting it.
To eliminate this issue, these steps are taken:
* Restore original condition
'(data->__statep->__count & ~7) != ASCII_set'.
It is necessary since bits 0-2 may contain
number of buffered input characters.
* Check that queued character is not NUL.
Similar step is taken for main conversion loop.
Bundled test case follows following logic:
* Try to convert ISO-2022-JP-3 escape sequence
switching active character set
* Reset internal state by providing NULL as input buffer
* Ensure that nothing has been converted.
Paul A. Clarke [Tue, 19 Oct 2021 14:49:12 +0000 (09:49 -0500)]
[powerpc] Tighten contraints for asm constant parameters
There are a few places where only known numeric values are acceptable for
`asm` parameters, yet the constraint "i" is used. "i" can include
"symbolic constants whose values will be known only at assembly time or
later."
Use "n" instead of "i" where known numeric values are required.
Suggested-by: Segher Boessenkool <segher@kernel.crashing.org> Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Fangrui Song [Tue, 2 Nov 2021 17:07:59 +0000 (10:07 -0700)]
regex: Unnest nested functions in regcomp.c
This refactor moves four functions out of a nested scope and converts
them into static always_inline functions. collseqwc, table_size,
symb_table, extra are now initialized to zero because they are passed as
function arguments.
On x86-64, .text is 16 byte larger likely due to the 4 stores.
This is nothing compared to the amount of work that regcomp has to do
looking up the collation weights, or other functions.
If the non-buildable `sysdeps/generic/dl-machine.h` doesn't count,
this patch removes the last `auto inline` usage from glibc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
elf: Assume disjointed .rela.dyn and .rela.plt for loader
The patch removes the the ELF_DURING_STARTUP optimization and assume
both .rel.dyn and .rel.plt might not be subsequent. This allows some
code simplification since relocation will be handled independently
where it is done on bootstrap.
At least on x86_64_64, I can not measure any performance implications.
Running 10000 time the command
LD_DEBUG=statistics ./elf/ld.so ./libc.so
And filtering the "total startup time in dynamic loader" result,
the geometric mean is:
arm: Use internal symbol for _dl_argv on _dl_start_user
The lld does not support R_ARM_GOTOFF32 to preemptible symbol (_dl_argv
has default visibility). Use the internal alias instead (one option
would to use HIDDEN_JUMPTARGET, bu the macro is not defined for
!__ASSEMBLER__ and I made this patch arm-specific to avoid require to
check extensivelly on other architecture it this might break something).
H.J. Lu [Fri, 29 Oct 2021 19:56:53 +0000 (12:56 -0700)]
x86-64: Remove Prefer_AVX2_STRCMP
Remove Prefer_AVX2_STRCMP to enable EVEX strcmp. When comparing 2 32-byte
strings, EVEX strcmp has been improved to require 1 load, 1 VPTESTM, 1
VPCMP, 1 KMOVD and 1 INCL instead of 2 loads, 3 VPCMPs, 2 KORDs, 1 KMOVD
and 1 TESTL while AVX2 strcmp requires 1 load, 2 VPCMPEQs, 1 VPMINU, 1
VPMOVMSKB and 1 TESTL. EVEX strcmp is now faster than AVX2 strcmp by up
to 40% on Tiger Lake and Ice Lake.
H.J. Lu [Fri, 29 Oct 2021 19:40:20 +0000 (12:40 -0700)]
x86-64: Improve EVEX strcmp with masked load
In strcmp-evex.S, to compare 2 32-byte strings, replace
VMOVU (%rdi, %rdx), %YMM0
VMOVU (%rsi, %rdx), %YMM1
/* Each bit in K0 represents a mismatch in YMM0 and YMM1. */
VPCMP $4, %YMM0, %YMM1, %k0
VPCMP $0, %YMMZERO, %YMM0, %k1
VPCMP $0, %YMMZERO, %YMM1, %k2
/* Each bit in K1 represents a NULL in YMM0 or YMM1. */
kord %k1, %k2, %k1
/* Each bit in K1 represents a NULL or a mismatch. */
kord %k0, %k1, %k1
kmovd %k1, %ecx
testl %ecx, %ecx
jne L(last_vector)
with
VMOVU (%rdi, %rdx), %YMM0
VPTESTM %YMM0, %YMM0, %k2
/* Each bit cleared in K1 represents a mismatch or a null CHAR
in YMM0 and 32 bytes at (%rsi, %rdx). */
VPCMP $0, (%rsi, %rdx), %YMM0, %k1{%k2}
kmovd %k1, %ecx
incl %ecx
jne L(last_vector)
It makes EVEX strcmp faster than AVX2 strcmp by up to 40% on Tiger Lake
and Ice Lake.
Sunil K Pandey [Wed, 27 Oct 2021 20:50:16 +0000 (13:50 -0700)]
benchtests: Add acosf function to bench-math
Add acosf function to bench-math and copy acosf-inputs to benchtests.
Motivation for this patch is to prepare for upcoming libmvec new
functions. Float and double version of libmvec functions stays
together.
acosf-inputs file generated from acos-inputs file using following
scaling formula:
f = d * (FLT_MAX/DBL_MAX)
Where d is input(double) and f is output(float). If scaled float value
is duplicate in new input file, nextafterf() function used to find next
float value, ensuring no duplicates.
Wilco Dijkstra [Fri, 29 Oct 2021 14:41:18 +0000 (15:41 +0100)]
benchtests: Improve bench-memcpy-random
Improve the random memcpy benchmark. Double the number of tests and increase
the size of the memory region to test between 32KB and 1024KB. This improves
accuracy on modern cores. Clean up formatting of the frequency array.