include/math.h has a mechanism to redirect internal calls to various
libm functions, that can often be inlined by the compiler, to call
non-exported __* names for those functions in the case when the calls
aren't inlined, with the redirection being disabled when
NO_MATH_REDIRECT. Add fma to the functions to which this mechanism is
applied.
At present, libm-internal fma calls (generally to __builtin_fma*
functions) are only done when it's known the call will be inlined,
with alternative code not relying on an fma operation being used in
the caller otherwise. This patch is in preparation for adding the TS
18661 / C2X narrowing fma functions to glibc; it will be natural for
the narrowing function implementations to call the underlying fma
functions unconditionally, with this either being inlined or resulting
in an __fma* call. (Using two levels of round-to-odd computation like
that, in the case where there isn't an fma hardware instruction, isn't
optimal but is certainly a lot simpler for the initial implementation
than writing different narrowing fma implementations for all the
various pairs of formats.)
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch (using
<https://sourceware.org/pipermail/libc-alpha/2021-September/130991.html>
to fix installed library stripping in build-many-glibcs.py). Also
tested for x86_64.
While originally this definition was indeed used to distinguish between
the cases where the GSCOPE flag was stored in TCB or not, it has since
become used as a general way to distinguish between HTL and NPTL.
THREAD_GSCOPE_IN_TCB will be removed in the following commits, as HTL,
which currently is the only port that does not put the flag into TCB,
will get ported to put the GSCOPE flag into the TCB as well. To prepare
for that change, migrate all code that wants to distinguish between HTL
and NPTL to use PTHREAD_IN_LIBC instead, which is a better choice since
the distinction mostly has to do with whether libc has access to the
list of thread structures and therefore can initialize thread-local
storage.
The parts of code that actually depend on whether the GSCOPE flag is in
TCB are left unchanged.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20210907133325.255690-2-bugaevc@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Linux 5.14 adds constants MADV_POPULATE_READ and MADV_POPULATE_WRITE
(with the same values on all architectures). Add these to glibc's
bits/mman-linux.h.
Tested for x86_64.
This patch updates the kernel version in the test tst-mman-consts.py
to 5.14. (There are no new MAP_* constants covered by this test in
5.14 that need any other header changes.)
Tested with build-many-glibcs.py.
A new thread exit lock and flag are introduced. They are used to
detect that the thread is about to exit or has exited in
__pthread_kill_internal, and the signal is not sent in this case.
The test sysdeps/pthread/tst-pthread_cancel-select-loop.c is derived
from a downstream test originally written by Marek Polacek.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This closes one remaining race condition related to bug 12889: if
the thread already exited on the kernel side, returning ESRCH
is not correct because that error is reserved for the thread IDs
(pthread_t values) whose lifetime has ended. In case of a
kernel-side exit and a valid thread ID, no signal needs to be sent
and cancellation does not have an effect, so just return 0.
sysdeps/pthread/tst-kill4.c triggers undefined behavior and is
removed with this commit.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch adds the narrowing square root functions from TS 18661-1 /
TS 18661-3 / C2X to glibc's libm: fsqrt, fsqrtl, dsqrtl, f32sqrtf64,
f32sqrtf32x, f32xsqrtf64 for all configurations; f32sqrtf64x,
f32sqrtf128, f64sqrtf64x, f64sqrtf128, f32xsqrtf64x, f32xsqrtf128,
f64xsqrtf128 for configurations with _Float64x and _Float128;
__f32sqrtieee128 and __f64sqrtieee128 aliases in the powerpc64le case
(for calls to fsqrtl and dsqrtl when long double is IEEE binary128).
Corresponding tgmath.h macro support is also added.
The changes are mostly similar to those for the other narrowing
functions previously added, so the description of those generally
applies to this patch as well. However, the not-actually-narrowing
cases (where the two types involved in the function have the same
floating-point format) are aliased to sqrt, sqrtl or sqrtf128 rather
than needing a separately built not-actually-narrowing function such
as was needed for add / sub / mul / div. Thus, there is no
__nldbl_dsqrtl name for ldbl-opt because no such name was needed
(whereas the other functions needed such a name since the only other
name for that entry point was e.g. f32xaddf64, not reserved by TS
18661-1); the headers are made to arrange for sqrt to be called in
that case instead.
The DIAG_* calls in sysdeps/ieee754/soft-fp/s_dsqrtl.c are because
they were observed to be needed in GCC 7 testing of
riscv32-linux-gnu-rv32imac-ilp32. The other sysdeps/ieee754/soft-fp/
files added didn't need such DIAG_* in any configuration I tested with
build-many-glibcs.py, but if they do turn out to be needed in more
files with some other configuration / GCC version, they can always be
added there.
I reused the same test inputs in auto-libm-test-in as for
non-narrowing sqrt rather than adding extra or separate inputs for
narrowing sqrt. The tests in libm-test-narrow-sqrt.inc also follow
those for non-narrowing sqrt.
Tested as followed: natively with the full glibc testsuite for x86_64
(GCC 11, 7, 6) and x86 (GCC 11); with build-many-glibcs.py with GCC
11, 7 and 6; cross testing of math/ tests for powerpc64le, powerpc32
hard float, mips64 (all three ABIs, both hard and soft float). The
different GCC versions are to cover the different cases in tgmath.h
and tgmath.h tests properly (GCC 6 has _Float* only as typedefs in
glibc headers, GCC 7 has proper _Float* support, GCC 8 adds
__builtin_tgmath).
Linux 5.14 has two new syscalls, memfd_secret (on some architectures
only) and quotactl_fd. Update syscall-names.list and regenerate the
arch-syscall.h headers with build-many-glibcs.py update-syscalls.
Tested with build-many-glibcs.py.
{f,l,}xstat stub for MIPS is using INTERNAL_SYSCALL
to do xstat syscall for glibc ver, However it leaves
errno untouched and thus giving bad errno output.
Setup errno properly when syscall returns non-zero.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch updates unroll8 code so as not to degrade at the peak
performance 16KB for both FX1000 and FX700.
Inserted 2 instructions at the beginning of the unroll8 loop,
cmp and branch, are a workaround that is found heuristically.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date. Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.
Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions. These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.
The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively. These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:
https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dchttps://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch updates unroll8 code so as not to degrade at the peak
performance 16KB for both FX1000 and FX700.
Inserted 2 instructions at the beginning of the unroll8 loop,
cmp and branch, are a workaround that is found heuristically.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
When using LLD (LLVM linker) as the linker, configure prints a confusing
message.
*** These critical programs are missing or too old: GNU ld
LLD>=13.0.0 can build glibc --enable-static-pie. (8.0.0 needs one
workaround for -Wl,-defsym=_begin=0. 9.0.0 works with
--disable-static-pie).
XFAIL two tests sysdeps/x86/tst-ifunc-isa-* which have the BZ #28154
issue (LLD follows the PowerPC port of GNU ld for ifunc by placing
IRELATIVE relocations in .rela.dyn, triggering a glibc ifunc fragility).
The set of dynamic symbols is the same with GNU ld and LLD,
modulo unused SHN_ABS version node symbols.
For comparison, gold does not support --enable-static-pie
yet (--no-dynamic-linker is unsupported BZ #22221), yet
has 6 failures more than LLD. gold linked libc.so has
larger .dynsym differences with GNU ld and LLD
(non-default version symbols are changed to default versions
by a version script BZ #28196).
Optimize loads of all bits set into ZMM register in AVX512 SVML codes
by replacing
vpbroadcastq .L_2il0floatpacket.16(%rip), %zmmX
and
vmovups .L_2il0floatpacket.13(%rip), %zmmX
with
vpternlogd $0xff, %zmmX, %zmmX, %zmmX
This fixes BZ #28252.
The Autoconf documentation for the AC_CACHE_CHECK macro states:
The commands-to-set-it must have no side effects except for setting
the variable cache-id, see below.
However, the tests for support of -msahf and -mmovbe were embedded in
the commands-to-set-it for lib_cv_include_x86_isa_level. This had the
consequence that libc_cv_have_x86_lahf_sahf and libc_cv_have_x86_movbe
were not defined whenever lib_cv_include_x86_isa_level was read from
cache. These variables' being undefined meant that their unquoted use
in later test expressions led to the 'test' built-in's misparsing its
arguments and emitting errors like "test: =: unexpected operator" or
"test: =: unary operator expected", depending on the particular shell.
This commit refactors the tests for LAHF/SAHF and MOVBE instruction
support into their own AC_CACHE_CHECK macro invocations to obey the
rule that the commands-to-set-it must have no side effects other than
setting the variable named by cache-id.
Signed-off-by: Matt Whitlock <sourceware@mattwhitlock.name>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
and drop reliance on _GLOBAL_OFFSET_TABLE_[0] being the link-time
address of _DYNAMIC. &__ehdr_start is a better way to get the load address.
This is similar to commits b37b75d269
(x86-64) and 43d06ed218 (aarch64).
Reviewed-by: Joseph Myers <joseph@codesourcery.com>
&__ehdr_start is a better way to get the load address.
This is similar to commits b37b75d269
(x86-64) and 43d06ed218 (aarch64).
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
They provide TLS_GD/TLS_LD/TLS_IE/TLS_IE macros for TLS testing. Now
that we have migrated to __thread and tls_model attributes, these macros
are unused and the tls-macros.h files can retire.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
and drop reliance on _GLOBAL_OFFSET_TABLE_[0] being the link-time
address of _DYNAMIC. &__ehdr_start is a better way to get the load address.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
elf/tls-macros.h was added for TLS testing when GCC did not support
__thread. __thread and tls_model attributes are mature now and have been
used by many newer tests.
Also delete tst-tls2.c which tests .tls_common (unused by modern GCC and
unsupported by Clang/LLD). .tls_common and .tbss definition are almost
identical after linking, so the runtime test doesn't add additional
coverage. Assembler and linker tests should be on the binutils side.
When LLD 13.0.0 is allowed in configure.ac
(https://sourceware.org/pipermail/libc-alpha/2021-August/129866.html),
`make check` result is on par with glibc built with GNU ld on aarch64
and x86_64.
As a future clean-up, TLS_GD/TLS_LD/TLS_IE/TLS_IE macros can be removed from
sysdeps/*/tls-macros.h. We can add optional -mtls-dialect={gnu2,trad}
tests to ensure coverage.
Tested on aarch64-linux-gnu, powerpc64le-linux-gnu, and x86_64-linux-gnu.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Gnumach's 0650a4ee30e3 implements support for high bits being set in the
mask parameter of vm_map. This allows to remove the fmh kludge that was
masking away the address range by mapping a dumb area there.
In "mips: align stack in clone [BZ #28223]"
(commit 1f51cd9a86) I made a mistake: I
misbelieved one "word" was 2-byte and "doubleword" should be 4-byte.
But in MIPS ABI one "word" is defined 32-bit (4-byte), so "doubleword" is
8-byte [1], and "quadword" is 16-byte [2].
[1]: "System V Application Binary Interface: MIPS(R) RISC Processor
Supplement, 3rd edition", page 3-31
[2]: "MIPSpro(TM) 64-Bit Porting and Transition Guide", page 23
The MIPS O32 ABI requires 4 byte aligned stack, and the MIPS N64 and N32
ABI require 8 byte aligned stack. Previously if the caller passed an
unaligned stack to clone the the child misbehaved.
Fixes bug 28223.
When the memory object is read-only, the kernel would be right in
refusing max vmprot containing VM_PROT_WRITE.
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
The AArch64 ABI is largely platform agnostic and does not specify
_GLOBAL_OFFSET_TABLE_[0] ([1]). glibc ld.so turns out to be probably the
only user of _GLOBAL_OFFSET_TABLE_[0] and GNU ld defines the value
to the link-time address _DYNAMIC. [2]
In 2012, __ehdr_start was implemented in GNU ld and gold in binutils
2.23. Using adrp+add / (-mcmodel=tiny) adr to access
__ehdr_start/_DYNAMIC gives us a robust way to get the load address and
the link-time address of _DYNAMIC.
[1]: From a psABI maintainer, https://bugs.llvm.org/show_bug.cgi?id=49672#c2
[2]: LLD's aarch64 port does not set _GLOBAL_OFFSET_TABLE_[0] to the
link-time address _DYNAMIC.
LLD is widely used on aarch64 Android and ChromeOS devices. Software
just works without the need for _GLOBAL_OFFSET_TABLE_[0].
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Simplify handling of remaining bytes. Avoid lots of taken branches and complex
whilelo computations, instead unconditionally write vectors from the end.
Reviewed-by: Naohiro Tamura <naohirot@fujitsu.com>
Improve performance of large memsets. Simplify alignment code. For zero memset
use DC ZVA, which almost doubles performance. For non-zero memsets use the
unroll8 loop which is about 10% faster.
Reviewed-by: Naohiro Tamura <naohirot@fujitsu.com>
Improve performance of small memsets by reducing instruction counts and
improving code alignment. Bench-memset shows 35-45% performance gain for
small sizes.
Reviewed-by: Naohiro Tamura <naohirot@fujitsu.com>
Linux 5.13 adds a PTRACE_GET_RSEQ_CONFIGURATION constant, with an
associated ptrace_rseq_configuration structure.
Add this constant to the various sys/ptrace.h headers in glibc, with
the structure in bits/ptrace-shared.h (named struct
__ptrace_rseq_configuration in glibc, as with other such structures).
Tested for x86_64, and with build-many-glibcs.py.
Helper thread frees copied attribute on NOTIFY_REMOVED message
received from the OS kernel. Unfortunately, it fails to check whether
copied attribute actually exists (data.attr != NULL). This worked
earlier because free() checks passed pointer before actually
attempting to release corresponding memory. But
__pthread_attr_destroy assumes pointer is not NULL.
So passing NULL pointer to __pthread_attr_destroy will result in
segmentation fault. This scenario is possible if
notification->sigev_notify_attributes == NULL (which means default
thread attributes should be used).
Signed-off-by: Nikita Popov <npv1310@gmail.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
We'd like to support processors without Altivec or VSX, so check
the relevant hwcap bits before selecting them.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
A number of optimised memset routines assume the cacheline size is 128B,
so we better check before using them.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
We use PPC_FEATURE_HAS_VSX to select a number of POWER7 optimised
functions. These functions don't use any VSX instructions, so
PPC_FEATURE_ARCH_2_06 seems like a better fit.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
__REDIRECT and __THROW are not compatible with C++ due to the ordering of the
__asm__ alias and the throw specifier. __REDIRECT_NTH has to be used
instead.
Fixes commit 8a40aff86b ("io: Add time64 alias
for fcntl"), commit 82c395d91e ("misc: Add
time64 alias for ioctl"), commit b39ffab860
("Linux: Add time64 alias for prctl").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
