Fix libatomic build to support --disable-gnu-indirect-function on AArch64.
Always build atomic_16.S, add aliases to the __atomic_ functions if !HAVE_IFUNC.
Include auto-config.h in atomic_16.S to avoid having to pass defines via
makefiles. Fix build if HWCAP_ATOMICS/CPUID are not defined.
libatomic:
PR target/113986
* Makefile.in: Regenerated.
* Makefile.am: Make atomic_16.S not depend on HAVE_IFUNC.
Remove predefine of HAVE_FEAT_LSE128.
* acinclude.m4: Remove ARCH_AARCH64_HAVE_LSE128.
* configure: Regenerated.
* config/linux/aarch64/atomic_16.S: Add __atomic_ alias if !HAVE_IFUNC.
* config/linux/aarch64/host-config.h: Correctly handle !HAVE_IFUNC.
Add defines for HWCAP_ATOMICS and HWCAP_CPUID.
This patch is a revised version of the fix for PR other/113336.
Bootstrapping GCC on arm-linux-gnueabihf with --with-arch=armv6 currently
has a large number of FAILs in libatomic (regressions since last time I
attempted this). The failure mode is related to IFUNC handling with the
file tas_8_2_.o containing an unresolved reference to the function
libat_test_and_set_1_i2.
The following one line change, to build tas_1_2_.o when building tas_8_2_.o,
resolves the problem for me and restores the libatomic testsuite to 44
expected passes and 5 unsupported tests [from 22 unexpected failures
and 22 unresolved testcases].
`
2024-02-14 Roger Sayle <roger@nextmovesoftware.com>
Victor Do Nascimento <victor.donascimento@arm.com>
libatomic/ChangeLog
PR other/113336
* Makefile.am: Build tas_1_2_.o on ARCH_ARM_LINUX
* Makefile.in: Regenerate.
The exception defines in <fenv.h> do not match the exception bits
in the FPU status register on hppa-linux and hppa64-hpux11.11. On
linux, they match the trap enable bits. On 64-bit hpux, they match
the exception bits for IA64. The IA64 bits are in a different
order and location than HPPA. HP uses table look ups to reorder
the bits in code to test and raise exceptions.
All the architectures that I looked at just pass the FPU status
register to __atomic_feraiseexcept(). The simplest approach for
hppa is to define FE_INEXACT, etc, to match the status register
and not include <fenv.h>..
2024-02-03 John David Anglin <danglin@gcc.gnu.org>
libatomic/ChangeLog:
PR target/59778
* configure.tgt (hppa*): Set ARCH.
* config/pa/fenv.c: New file.
At present, Evaluation of both `has_lse2(hwcap)' and
`has_lse128(hwcap)' may require issuing an `mrs' instruction to query
a system register. This instruction, when issued from user-space
results in a trap by the kernel which then returns the value read in
by the system register. Given the undesirable nature of the
computational expense associated with the context switch, it is
important to implement mechanisms to, wherever possible, forgo the
operation.
In light of this, given how other architectural requirements serving
as prerequisites have long been assigned HWCAP bits by the kernel, we
can inexpensively query for their availability before attempting to
read any system registers. Where one of these early tests fail, we
can assert that the main feature of interest (be it LSE2 or LSE128)
cannot be present, allowing us to return from the function early and
skip the unnecessary expensive kernel-mediated access to system
registers.
libatomic/ChangeLog:
* config/linux/aarch64/host-config.h (has_lse2): Add test for LSE.
(has_lse128): Add test for LSE2.
The armv9.4-a architectural revision adds three new atomic operations
associated with the LSE128 feature:
* LDCLRP - Atomic AND NOT (bitclear) of a location with 128-bit
value held in a pair of registers, with original data loaded into
the same 2 registers.
* LDSETP - Atomic OR (bitset) of a location with 128-bit value held
in a pair of registers, with original data loaded into the same 2
registers.
* SWPP - Atomic swap of one 128-bit value with 128-bit value held
in a pair of registers.
It is worth noting that in keeping with existing 128-bit atomic
operations in `atomic_16.S', we have chosen to merge certain
less-restrictive orderings into more restrictive ones. This is done
to minimize the number of branches in the atomic functions, minimizing
both the likelihood of branch mispredictions and, in keeping code
small, limit the need for extra fetch cycles.
Past benchmarking has revealed that acquire is typically slightly
faster than release (5-10%), such that for the most frequently used
atomics (CAS and SWP) it makes sense to add support for acquire, as
well as release.
Likewise, it was identified that combining acquire and release typically
results in little to no penalty, such that it is of negligible benefit
to distinguish between release and acquire-release, making the
combining release/acq_rel/seq_cst a worthwhile design choice.
This patch adds the logic required to make use of these when the
architectural feature is present and a suitable assembler available.
In order to do this, the following changes are made:
1. Add a configure-time check to check for LSE128 support in the
assembler.
2. Edit host-config.h so that when N == 16, nifunc = 2.
3. Where available due to LSE128, implement the second ifunc, making
use of the novel instructions.
4. For atomic functions unable to make use of these new
instructions, define a new alias which causes the _i1 function
variant to point ahead to the corresponding _i2 implementation.
libatomic/ChangeLog:
* Makefile.am (AM_CPPFLAGS): add conditional setting of
-DHAVE_FEAT_LSE128.
* acinclude.m4 (LIBAT_TEST_FEAT_AARCH64_LSE128): New.
* config/linux/aarch64/atomic_16.S (LSE128): New macro
definition.
(libat_exchange_16): New LSE128 variant.
(libat_fetch_or_16): Likewise.
(libat_or_fetch_16): Likewise.
(libat_fetch_and_16): Likewise.
(libat_and_fetch_16): Likewise.
* config/linux/aarch64/host-config.h (IFUNC_COND_2): New.
(IFUNC_NCOND): Add operand size checking.
(has_lse2): Renamed from `ifunc1`.
(has_lse128): New.
(HWCAP2_LSE128): Likewise.
* configure.ac: Add call to
LIBAT_TEST_FEAT_AARCH64_LSE128.
* configure (ac_subst_vars): Regenerated via autoreconf.
* Makefile.in: Likewise.
* auto-config.h.in: Likewise.
With support for new atomic features in Armv9.4-a being indicated by
HWCAP2 bits, Libatomic's ifunc resolver must now query its second
argument, of type __ifunc_arg_t*.
We therefore make this argument known to libatomic, allowing us to
query hwcap2 bits in the following manner:
bool
resolver (unsigned long hwcap, const __ifunc_arg_t *features);
{
return (features->hwcap2 & HWCAP2_<FEAT_NAME>);
}
libatomic/ChangeLog:
* config/linux/aarch64/host-config.h (__ifunc_arg_t):
Conditionally-defined if `sys/ifunc.h' not found.
(_IFUNC_ARG_HWCAP): Likewise.
(IFUNC_COND_1): Pass __ifunc_arg_t argument to ifunc.
(ifunc1): Modify function signature to accept __ifunc_arg_t
argument.
* configure.tgt: Add second `const __ifunc_arg_t *features'
argument to IFUNC_RESOLVER_ARGS.
The introduction of further architectural-feature dependent ifuncs
for AArch64 makes hard-coding ifunc `_i<n>' suffixes to functions
cumbersome to work with. It is awkward to remember which ifunc maps
onto which arch feature and makes the code harder to maintain when new
ifuncs are added and their suffixes possibly altered.
This patch uses pre-processor `#define' statements to map each suffix to
a descriptive feature name macro, for example:
#define LSE(NAME) NAME##_i1
Where we wish to generate ifunc names with the pre-processor's token
concatenation feature, we add a level of indirection to previous macro
calls. If before we would have had`MACRO(<name>_i<n>)', we now have
`MACRO_FEAT(name, feature)'. Where we wish to refer to base
functionality (i.e., functions where ifunc suffixes are absent), the
original `MACRO(<name>)' may be used to bypass suffixing.
Consequently, for base functionality, where the ifunc suffix is
absent, the macro interface remains the same. For example, the entry
and endpoints of `libat_store_16' remain defined by:
ENTRY (libat_store_16)
and
END (libat_store_16)
For the LSE2 implementation of the same 16-byte atomic store, we now
have:
ENTRY_FEAT (libat_store_16, LSE2)
and
END_FEAT (libat_store_16, LSE2)
For the aliasing of function names, we define the following new
implementation of the ALIAS macro:
ALIAS (FN_BASE_NAME, FROM_SUFFIX, TO_SUFFIX)
Defining the `CORE(NAME)' macro to be the identity operator, it
returns the base function name unaltered and allows us to alias
target-specific ifuncs to the corresponding base implementation.
For example, we'd alias the LSE2 `libat_exchange_16' to it base
implementation with:
ALIAS (libat_exchange_16, LSE2, CORE)
libatomic/ChangeLog:
* config/linux/aarch64/atomic_16.S (CORE): New macro.
(LSE2): Likewise.
(ENTRY_FEAT): Likewise.
(ENTRY_FEAT1): Likewise.
(END_FEAT): Likewise.
(END_FEAT1): Likewise.
(ALIAS): Modify macro to take in `arch' arguments.
(ALIAS1): New.
Enable lock-free 128-bit atomics on AArch64. This is backwards compatible with
existing binaries (as for these GCC always calls into libatomic, so all 128-bit
atomic uses in a process are switched), gives better performance than locking
atomics and is what most users expect.
128-bit atomic loads use a load/store exclusive loop if LSE2 is not supported.
This results in an implicit store which is invisible to software as long as the
given address is writeable (which will be true when using atomics in real code).
This doesn't yet change __atomic_is_lock_free eventhough all atomics are finally
lock-free on AArch64.
libatomic:
* config/linux/aarch64/atomic_16.S: Implement lock-free ARMv8.0 atomics.
(libat_exchange_16): Merge RELEASE and ACQ_REL/SEQ_CST cases.
* config/linux/aarch64/host-config.h: Use atomic_16.S for baseline v8.0.
Add support for ifunc selection based on CPUID register. Neoverse N1 supports
atomic 128-bit load/store, so use the FEAT_USCAT ifunc like newer Neoverse
cores.
Reviewed-by: Kyrylo.Tkachov@arm.com
libatomic:
* config/linux/aarch64/host-config.h (ifunc1): Use CPUID in ifunc
selection.
Similar to commit fb5d27be27
"libgomp: Consider '--with-build-sysroot=[...]' for target libraries' build-tree testing (instead of build-time 'CC' etc.) [PR91884, PR109951]",
this is commit 5ff06d762a
"libatomic/test: Fix compilation for build sysroot" done differently,
avoiding build-tree testing use of any random gunk that may appear in
build-time 'CC'.
PR testsuite/109951
libatomic/
* configure.ac: 'AC_SUBST(SYSROOT_CFLAGS_FOR_TARGET)'.
* Makefile.in: Regenerate.
* configure: Likewise.
* testsuite/Makefile.in: Likewise.
* testsuite/lib/libatomic.exp (libatomic_init): If
'--with-build-sysroot=[...]' was specified, use it for build-tree
testing.
* testsuite/libatomic-site-extra.exp.in (GCC_UNDER_TEST): Don't
set.
(SYSROOT_CFLAGS_FOR_TARGET): Set.
./multilib.am already specifies this same command, and make warns about
the earlier one being ignored when seeing the later one. All that needs
retaining to still satisfy the preceding comment is the extra
dependency.
libatomic/
* Makefile.am (all-multi): Drop commands.
* Makefile.in: Update accordingly.
DYLD_LIBRARY_PATH is now removed from the environment for all system
tools, including the shell. Adapt the testsuite and pass the right
options to allow testing, even when the compiler and libraries have not
been installed.
gcc/ChangeLog:
* Makefile.in: set ENABLE_DARWIN_AT_RPATH in site.tmp.
gcc/testsuite/ChangeLog:
* gfortran.dg/coarray/caf.exp: Correctly set
libatomic flags.
* gfortran.dg/dg.exp: Likewise.
* lib/asan-dg.exp: Set correct -B flags.
* lib/atomic-dg.exp: Likewise.
* lib/target-libpath.exp: Handle ENABLE_DARWIN_AT_RPATH.
libatomic/ChangeLog:
* testsuite/lib/libatomic.exp: Pass correct flags on darwin.
libffi/ChangeLog:
* testsuite/lib/libffi.exp: Likewise.
libitm/ChangeLog:
* testsuite/lib/libitm.exp: Likewise.
* testsuite/libitm.c++/c++.exp: Likewise.
Recent Darwin versions place contraints on the use of run paths
specified in environment variables. This breaks some assumptions
in the GCC build.
This change allows the user to configure a Darwin build to use
'@rpath/libraryname.dylib' in library names and then to add an
embedded runpath to executables (and libraries with dependents).
The embedded runpath is added by default unless the user adds
'-nodefaultrpaths' to the link line.
For an installed compiler, it means that any executable built with
that compiler will reference the runtimes installed with the
compiler (equivalent to hard-coding the library path into the name
of the library).
During build-time configurations any "-B" entries will be added to
the runpath thus the newly-built libraries will be found by exes.
Since the install name is set in libtool, that decision needs to be
available here (but might also cause dependent ones in Makefiles,
so we need to export a conditional).
This facility is not available for Darwin 8 or earlier, however the
existing environment variable runpath does work there.
We default this on for systems where the external DYLD_LIBRARY_PATH
does not work and off for Darwin 8 or earlier. For systems that can
use either method, if the value is unset, we use the default (which
is currently DYLD_LIBRARY_PATH).
ChangeLog:
* configure: Regenerate.
* configure.ac: Do not add default runpaths to GCC exes
when we are building -static-libstdc++/-static-libgcc (the
default).
* libtool.m4: Add 'enable-darwin-at-runpath'. Act on the
enable flag to alter Darwin libraries to use @rpath names.
gcc/ChangeLog:
* aclocal.m4: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
* config/darwin.h: Handle Darwin rpaths.
* config/darwin.opt: Handle Darwin rpaths.
* Makefile.in: Handle Darwin rpaths.
gcc/ada/ChangeLog:
* gcc-interface/Makefile.in: Handle Darwin rpaths.
gcc/jit/ChangeLog:
* Make-lang.in: Handle Darwin rpaths.
libatomic/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libbacktrace/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libcc1/ChangeLog:
* configure: Regenerate.
libffi/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
libgcc/ChangeLog:
* config/t-slibgcc-darwin: Generate libgcc_s
with an @rpath name.
* config.host: Handle Darwin rpaths.
libgfortran/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths
libgm2/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* aclocal.m4: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
* libm2cor/Makefile.am: Handle Darwin rpaths.
* libm2cor/Makefile.in: Regenerate.
* libm2iso/Makefile.am: Handle Darwin rpaths.
* libm2iso/Makefile.in: Regenerate.
* libm2log/Makefile.am: Handle Darwin rpaths.
* libm2log/Makefile.in: Regenerate.
* libm2min/Makefile.am: Handle Darwin rpaths.
* libm2min/Makefile.in: Regenerate.
* libm2pim/Makefile.am: Handle Darwin rpaths.
* libm2pim/Makefile.in: Regenerate.
libgomp/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths
libitm/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libobjc/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libphobos/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
* libdruntime/Makefile.am: Handle Darwin rpaths.
* libdruntime/Makefile.in: Regenerate.
* src/Makefile.am: Handle Darwin rpaths.
* src/Makefile.in: Regenerate.
libquadmath/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libsanitizer/ChangeLog:
* asan/Makefile.am: Handle Darwin rpaths.
* asan/Makefile.in: Regenerate.
* configure: Regenerate.
* hwasan/Makefile.am: Handle Darwin rpaths.
* hwasan/Makefile.in: Regenerate.
* lsan/Makefile.am: Handle Darwin rpaths.
* lsan/Makefile.in: Regenerate.
* tsan/Makefile.am: Handle Darwin rpaths.
* tsan/Makefile.in: Regenerate.
* ubsan/Makefile.am: Handle Darwin rpaths.
* ubsan/Makefile.in: Regenerate.
libssp/ChangeLog:
* Makefile.am: Handle Darwin rpaths.
* Makefile.in: Regenerate.
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
libstdc++-v3/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
* src/Makefile.am: Handle Darwin rpaths.
* src/Makefile.in: Regenerate.
libvtv/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
lto-plugin/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
zlib/ChangeLog:
* configure: Regenerate.
* configure.ac: Handle Darwin rpaths.
These are the os support patches we have been grooming and maintaining
for quite a few years over on git.haiku-os.org. All of these
architectures are working and most have been stable for quite some time.
ChangeLog:
* configure: Regenerate.
* configure.ac: Add Haiku to list of ELF OSes
* libtool.m4: Update sys_lib_dlsearch_path_spec on Haiku.
gcc/ChangeLog:
* configure: Regenerate.
libatomic/ChangeLog:
* configure: Regenerate.
libbacktrace/ChangeLog:
* configure: Regenerate.
libcc1/ChangeLog:
* configure: Regenerate.
libffi/ChangeLog:
* configure: Regenerate.
libgfortran/ChangeLog:
* configure: Regenerate.
libgm2/ChangeLog:
* configure: Regenerate.
libgomp/ChangeLog:
* configure: Regenerate.
libitm/ChangeLog:
* configure: Regenerate.
libobjc/ChangeLog:
* configure: Regenerate.
libphobos/ChangeLog:
* configure: Regenerate.
libquadmath/ChangeLog:
* configure: Regenerate.
libsanitizer/ChangeLog:
* configure: Regenerate.
libssp/ChangeLog:
* configure: Regenerate.
libstdc++-v3/ChangeLog:
* configure: Regenerate.
libvtv/ChangeLog:
* configure: Regenerate.
lto-plugin/ChangeLog:
* configure: Regenerate.
zlib/ChangeLog:
* configure: Regenerate.
My previous nm patch handled all cases but one -- if the user set NM in
the environment to a path which contained an option, libtool's nm
detection tries to run nm against a copy of nm with the options in it:
e.g. if NM was set to "nm --blargle", and nm was found in /usr/bin, the
test would try to run "/usr/bin/nm --blargle /usr/bin/nm --blargle".
This is unlikely to be desirable: in this case we should run
"/usr/bin/nm --blargle /usr/bin/nm".
Furthermore, as part of this nm has to detect when the passed-in $NM
contains a path, and in that case avoid doing a path search itself.
This too was thrown off if an option contained something that looked
like a path, e.g. NM="nm -B../prev-gcc"; libtool then tries to run
"nm -B../prev-gcc nm" which rarely works well (and indeed it looks
to see whether that nm exists, finds it doesn't, and wrongly concludes
that nm -p or whatever does not work).
Fix all of these by clipping all options (defined as everything
including and after the first " -") before deciding whether nm
contains a path (but not using the clipped value for anything else),
and then removing all options from the path-modified nm before
looking to see whether that nm existed.
NM=my-nm now does a path search and runs e.g.
/usr/bin/my-nm -B /usr/bin/my-nm
NM=/usr/bin/my-nm now avoids a path search and runs e.g.
/usr/bin/my-nm -B /usr/bin/my-nm
NM="my-nm -p../wombat" now does a path search and runs e.g.
/usr/bin/my-nm -p../wombat -B /usr/bin/my-nm
NM="../prev-binutils/new-nm -B../prev-gcc" now avoids a path search:
../prev-binutils/my-nm -B../prev-gcc -B ../prev-binutils/my-nm
This seems to be all combinations, including those used by GCC bootstrap
(which, before this commit, fails to bootstrap when configured
--with-build-config=bootstrap-lto, because the lto plugin is now using
--export-symbols-regex, which requires libtool to find a working nm,
while also using -B../prev-gcc to point at the lto plugin associated
with the GCC just built.)
Regenerate all affected configure scripts.
ChangeLog:
* libtool.m4 (LT_PATH_NM): Handle user-specified NM with
options, including options containing paths.
gcc/ChangeLog:
* configure: Regenerate.
libatomic/ChangeLog:
* configure: Regenerate.
libbacktrace/ChangeLog:
* configure: Regenerate.
libcc1/ChangeLog:
* configure: Regenerate.
libffi/ChangeLog:
* configure: Regenerate.
libgfortran/ChangeLog:
* configure: Regenerate.
libgm2/ChangeLog:
* configure: Regenerate.
libgomp/ChangeLog:
* configure: Regenerate.
libitm/ChangeLog:
* configure: Regenerate.
libobjc/ChangeLog:
* configure: Regenerate.
libphobos/ChangeLog:
* configure: Regenerate.
libquadmath/ChangeLog:
* configure: Regenerate.
libsanitizer/ChangeLog:
* configure: Regenerate.
libssp/ChangeLog:
* configure: Regenerate.
libstdc++-v3/ChangeLog:
* configure: Regenerate.
libvtv/ChangeLog:
* configure: Regenerate.
lto-plugin/ChangeLog:
* configure: Regenerate.
zlib/ChangeLog:
* configure: Regenerate.
Libtool needs to get BSD-format (or MS-format) output out of the system
nm, so that it can scan generated object files for symbol names for
-export-symbols-regex support. Some nms need specific flags to turn on
BSD-formatted output, so libtool checks for this in its AC_PATH_NM.
Unfortunately the code to do this has a pair of interlocking flaws:
- it runs the test by doing an nm of /dev/null. Some platforms
reasonably refuse to do an nm on a device file, but before now this
has only been worked around by assuming that the error message has a
specific textual form emitted by Tru64 nm, and that getting this
error means this is Tru64 nm and that nm -B would work to produce
BSD-format output, even though the test never actually got anything
but an error message out of nm -B. This is fixable by nm'ing *nm
itself* (since we necessarily have a path to it).
- the test is entirely skipped if NM is set in the environment, on the
grounds that the user has overridden the test: but the user cannot
reasonably be expected to know that libtool wants not only nm but
also flags forcing BSD-format output. Worse yet, one such "user" is
the top-level Cygnus configure script, which neither tests for
nor specifies any BSD-format flags. So platforms needing BSD-format
flags always fail to set them when run in a Cygnus tree, breaking
-export-symbols-regex on such platforms. Libtool also needs to
augment $LD on some platforms, but this is done unconditionally,
augmenting whatever the user specified: the nm check should do the
same.
One wrinkle: if the user has overridden $NM, a path might have been
provided: so we use the user-specified path if there was one, and
otherwise do the path search as usual. (If the nm specified doesn't
work, this might lead to a few extra pointless path searches -- but
the test is going to fail anyway, so that's not a problem.)
(Tested with NM unset, and set to nm, /usr/bin/nm, my-nm where my-nm is a
symlink to /usr/bin/nm on the PATH, and /not-on-the-path/my-nm where
*that* is a symlink to /usr/bin/nm.)
ChangeLog:
* libtool.m4 (LT_PATH_NM): Try BSDization flags with a user-provided
NM, if there is one. Run nm on itself, not on /dev/null, to avoid
errors from nms that refuse to work on non-regular files. Remove
other workarounds for this problem. Strip out blank lines from the
nm output.
fixincludes/ChangeLog:
* configure: Regenerate.
gcc/ChangeLog:
* configure: Regenerate.
libatomic/ChangeLog:
* configure: Regenerate.
libbacktrace/ChangeLog:
* configure: Regenerate.
libcc1/ChangeLog:
* configure: Regenerate.
libffi/ChangeLog:
* configure: Regenerate.
libgfortran/ChangeLog:
* configure: Regenerate.
libgm2/ChangeLog:
* configure: Regenerate.
libgomp/ChangeLog:
* configure: Regenerate.
libitm/ChangeLog:
* configure: Regenerate.
libobjc/ChangeLog:
* configure: Regenerate.
libphobos/ChangeLog:
* configure: Regenerate.
libquadmath/ChangeLog:
* configure: Regenerate.
libsanitizer/ChangeLog:
* configure: Regenerate.
libssp/ChangeLog:
* configure: Regenerate.
libstdc++-v3/ChangeLog:
* configure: Regenerate.
libvtv/ChangeLog:
* configure: Regenerate.
lto-plugin/ChangeLog:
* configure: Regenerate.
zlib/ChangeLog:
* configure: Regenerate.
AR from older binutils doesn't work with --plugin and rc:
[hjl@gnu-cfl-2 bin]$ touch foo.c
[hjl@gnu-cfl-2 bin]$ ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
[hjl@gnu-cfl-2 bin]$ ./ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
./ar: no operation specified
[hjl@gnu-cfl-2 bin]$ ./ar --version
GNU ar (Linux/GNU Binutils) 2.29.51.0.1.20180112
Copyright (C) 2018 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later version.
This program has absolutely no warranty.
[hjl@gnu-cfl-2 bin]$
Check if AR works with --plugin and rc before passing --plugin to AR and
RANLIB.
ChangeLog:
* configure: Regenerated.
* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Check if AR works with
--plugin and rc before enabling --plugin.
config/ChangeLog:
* gcc-plugin.m4 (GCC_PLUGIN_OPTION): Check if AR works with
--plugin and rc before enabling --plugin.
gcc/ChangeLog:
* configure: Regenerate.
libatomic/ChangeLog:
* configure: Regenerate.
libbacktrace/ChangeLog:
* configure: Regenerate.
libcc1/ChangeLog:
* configure: Regenerate.
libffi/ChangeLog:
* configure: Regenerate.
libgfortran/ChangeLog:
* configure: Regenerate.
libgm2/ChangeLog:
* configure: Regenerate.
libgomp/ChangeLog:
* configure: Regenerate.
libiberty/ChangeLog:
* configure: Regenerate.
libitm/ChangeLog:
* configure: Regenerate.
libobjc/ChangeLog:
* configure: Regenerate.
libphobos/ChangeLog:
* configure: Regenerate.
libquadmath/ChangeLog:
* configure: Regenerate.
libsanitizer/ChangeLog:
* configure: Regenerate.
libssp/ChangeLog:
* configure: Regenerate.
libstdc++-v3/ChangeLog:
* configure: Regenerate.
libvtv/ChangeLog:
* configure: Regenerate.
lto-plugin/ChangeLog:
* configure: Regenerate.
zlib/ChangeLog:
* configure: Regenerate.
We used to skip ifunc check when CX16 is available. But now we use
CX16+AVX+Intel/AMD for the "perfect" 16b load implementation, so CX16
alone is not a sufficient reason not to use ifunc (see PR104688).
This causes a subtle and annoying issue: when GCC is built with a
higher -march= setting in CFLAGS_FOR_TARGET, ifunc is disabled and
the worst (locked) implementation of __atomic_load_16 is always used.
There seems no good way to check if the CPU is Intel or AMD from
the built-in macros (maybe we can check every known model like __skylake,
__bdver2, ..., but it will be very error-prune and require an update
whenever we add the support for a new x86 model). The best thing we can
do seems "always try ifunc" here.
libatomic/ChangeLog:
* configure.tgt: For x86_64, always set try_ifunc=yes.
The LSE2 ifunc for 16-byte atomic load requires a barrier before the LDP -
without it, it effectively has Load-AcquirePC semantics similar to LDAPR,
which is less restrictive than what __ATOMIC_SEQ_CST requires. This patch
fixes this and adds comments to make it easier to see which sequence is
used for each case. Use a load/store exclusive loop for store to simplify
testing memory ordering is correct (it is slightly faster too).
libatomic/
PR libgcc/108891
* config/linux/aarch64/atomic_16.S: Fix libat_load_16_i1.
Add comments describing the memory order.
This is a follow-up to commit a4c6bd0821
introducing a runtime check for alignment for 16 byte atomic
compare-exchange, load, and store.
libatomic/ChangeLog:
* config/s390/cas_n.c: New file.
* config/s390/load_n.c: New file.
* config/s390/store_n.c: New file.
Without this change bootstrap fails for x86_64-w64-mingw32 with
--disable-threads=single because there is no lock.c file chosen by
libatomic's configure.
libatomic/ChangeLog:
* configure.tgt (config_path) [target_thread_file=single]:
Use 'mingw' config.
Add support for AArch64 LSE and LSE2 to libatomic. Disable outline atomics,
and use LSE ifuncs for 1-8 byte atomics and LSE2 ifuncs for 16-byte atomics.
On Neoverse V1, 16-byte atomics are ~4x faster due to avoiding locks.
Note this is safe since we swap all 16-byte atomics using the same ifunc,
so they either use locks or LSE2 atomics, but never a mix. This also improves
ABI compatibility with LLVM: its inlined 16-byte atomics are compatible with
the new libatomic if LSE2 is supported.
libatomic/
* Makefile.in: Regenerated with automake 1.15.1.
* Makefile.am: Add atomic_16.S for AArch64.
* configure.tgt: Disable outline atomics in AArch64 build.
* config/linux/aarch64/atomic_16.S: New file - implementation of
ifuncs for 16-byte atomics.
* config/linux/aarch64/host-config.h: Enable ifuncs, use LSE
(HWCAP_ATOMICS) for 1-8-byte atomics and LSE2 (HWCAP_USCAT) for
16-byte atomics.
