On nvptx (using a Quadro K2000 with driver 470.103.01) I ran into this:
...
FAIL: gcc.dg/atomic/stdatomic-flag-2.c -O1 execution test
...
which mimimized to:
...
#include <stdatomic.h>
atomic_flag a = ATOMIC_FLAG_INIT;
int main () {
if ((atomic_flag_test_and_set) (&a))
__builtin_abort ();
return 0;
}
...
The atomic_flag_test_and_set is implemented using __atomic_test_and_set_1,
which corresponds to the "word-sized compare-and-swap loop" version of
libat_test_and_set in libatomic/tas_n.c.
The semantics of a test-and-set is that the return value is "true if and only
if the previous contents were 'set'".
But the code uses:
...
return woldval != 0;
...
which means it doesn't look only at the byte that was either set or not set,
but at the entire word.
Fix this by using instead:
...
return (woldval & ((UTYPE) ~(UTYPE) 0 << shift)) != 0;
...
Tested on nvptx.
libatomic/ChangeLog:
2022-03-24 Tom de Vries <tdevries@suse.de>
PR target/105011
* tas_n.c (libat_test_and_set): Fix return value.
As mentioned in the PR, the latest Intel SDM has added:
"Processors that enumerate support for Intel® AVX (by setting the feature flag CPUID.01H:ECX.AVX[bit 28])
guarantee that the 16-byte memory operations performed by the following instructions will always be
carried out atomically:
• MOVAPD, MOVAPS, and MOVDQA.
• VMOVAPD, VMOVAPS, and VMOVDQA when encoded with VEX.128.
• VMOVAPD, VMOVAPS, VMOVDQA32, and VMOVDQA64 when encoded with EVEX.128 and k0 (masking disabled).
(Note that these instructions require the linear addresses of their memory operands to be 16-byte
aligned.)"
The following patch deals with it just on the libatomic library side so far,
currently (since ~ 2017) we emit all the __atomic_* 16-byte builtins as
library calls since and this is something that we can hopefully backport.
The patch simply introduces yet another ifunc variant that takes priority
over the pure CMPXCHG16B one, one that checks AVX and CMPXCHG16B bits and
on non-Intel clears the AVX bit during detection for now (if AMD comes
with the same guarantee, we could revert the config/x86/init.c hunk),
which implements 16-byte atomic load as vmovdqa and 16-byte atomic store
as vmovdqa followed by mfence.
2022-03-17 Jakub Jelinek <jakub@redhat.com>
PR target/104688
* Makefile.am (IFUNC_OPTIONS): Change on x86_64 to -mcx16 -mcx16.
(libatomic_la_LIBADD): Add $(addsuffix _16_2_.lo,$(SIZEOBJS)) for
x86_64.
* Makefile.in: Regenerated.
* config/x86/host-config.h (IFUNC_COND_1): For x86_64 define to
both AVX and CMPXCHG16B bits.
(IFUNC_COND_2): Define.
(IFUNC_NCOND): For x86_64 define to 2 * (N == 16).
(MAYBE_HAVE_ATOMIC_CAS_16, MAYBE_HAVE_ATOMIC_EXCHANGE_16,
MAYBE_HAVE_ATOMIC_LDST_16): Define to IFUNC_COND_2 rather than
IFUNC_COND_1.
(HAVE_ATOMIC_CAS_16): Redefine to 1 whenever IFUNC_ALT != 0.
(HAVE_ATOMIC_LDST_16): Redefine to 1 whenever IFUNC_ALT == 1.
(atomic_compare_exchange_n): Define whenever IFUNC_ALT != 0
on x86_64 for N == 16.
(__atomic_load_n, __atomic_store_n): Redefine whenever IFUNC_ALT == 1
on x86_64 for N == 16.
(atomic_load_n, atomic_store_n): New functions.
* config/x86/init.c (__libat_feat1_init): On x86_64 clear bit_AVX
if CPU vendor is not Intel.
libatomic/ChangeLog:
* acinclude.m4: Detect *_ld_is_mold and use it.
* configure: Regenerate.
libgomp/ChangeLog:
* acinclude.m4: Detect *_ld_is_mold and use it.
* configure: Regenerate.
libitm/ChangeLog:
* acinclude.m4: Detect *_ld_is_mold and use it.
* configure: Regenerate.
libstdc++-v3/ChangeLog:
* acinclude.m4: Detect *_ld_is_mold and use it.
* configure: Regenerate.
Resolves:
PR bootstrap/101379 - libatomic arm build failure after r12-2132 due to -Warray-bounds on a constant address
libatomic/ChangeLog:
PR bootstrap/101379
* config/linux/arm/host-config.h (__kernel_helper_version): New
function. Adjust shadow macro.
The recent changes to error on mixing -march=i386 and -fcf-protection broke
bootstrap. This patch changes lib{atomic,gomp,itm} configury, so that it
only adds -march=i486 to flags if really needed (i.e. when 486 or later isn't
on by default already). Similarly, it will not use ifuncs if -mcx16
(or -march=i686 for 32-bit) is on by default.
2021-01-15 Jakub Jelinek <jakub@redhat.com>
PR target/70454
libatomic/
* configure.tgt: For i?86 and x86_64 determine if -march=i486 needs to
be added through preprocessor check on
__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4. Determine if try_ifunc is needed
based on preprocessor check on __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
or __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8.
libgomp/
* configure.tgt: For i?86 and x86_64 determine if -march=i486 needs to
be added through preprocessor check on
__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4.
libitm/
* configure.tgt: For i?86 and x86_64 determine if -march=i486 needs to
be added through preprocessor check on
__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4.
The change in major version (and the increment from Darwin19 to 20)
caused libtool tests to fail which resulted in incorrect build settings
for shared libraries.
We take this opportunity to sort out the shared undefined symbols state
rather than propagating the current unsound behaviour into a new rev.
This change means that we default to the case that missing symbols are
considered an error, and if one wants to allow this intentionally, the
confiuration for that case should be set appropriately.
Three existing cases need undefined dynamic lookup:
libitm, where there is already a configuration mechanism to add the
flags.
libcc1, where we add simple configuration to add the flags for Darwin.
libsanitizer, where we can add to the existing extra flags.
libcc1/ChangeLog:
PR target/97865
* Makefile.am: Add dynamic_lookup to LD flags for Darwin.
* configure.ac: Test for Darwin host and set a flag.
* Makefile.in: Regenerate.
* configure: Regenerate.
libitm/ChangeLog:
PR target/97865
* configure.tgt: Add dynamic_lookup to XLDFLAGS for Darwin.
* configure: Regenerate.
libsanitizer/ChangeLog:
PR target/97865
* configure.tgt: Add dynamic_lookup to EXTRA_CXXFLAGS for
Darwin.
* configure: Regenerate.
ChangeLog:
PR target/97865
* libtool.m4: Update handling of Darwin platform link flags
for Darwin20.
gcc/ChangeLog:
PR target/97865
* configure: Regenerate.
libatomic/ChangeLog:
PR target/97865
* configure: Regenerate.
libbacktrace/ChangeLog:
PR target/97865
* configure: Regenerate.
libffi/ChangeLog:
PR target/97865
* configure: Regenerate.
libgfortran/ChangeLog:
PR target/97865
* configure: Regenerate.
libgomp/ChangeLog:
PR target/97865
* configure: Regenerate.
libhsail-rt/ChangeLog:
PR target/97865
* configure: Regenerate.
libobjc/ChangeLog:
PR target/97865
* configure: Regenerate.
libphobos/ChangeLog:
PR target/97865
* configure: Regenerate.
libquadmath/ChangeLog:
PR target/97865
* configure: Regenerate.
libssp/ChangeLog:
PR target/97865
* configure: Regenerate.
libstdc++-v3/ChangeLog:
PR target/97865
* configure: Regenerate.
libvtv/ChangeLog:
PR target/97865
* configure: Regenerate.
zlib/ChangeLog:
PR target/97865
* configure: Regenerate.
AIX caches shared objects in archives with read-other permission.
libgomp and libatomic might be in use during the build or testing, which
may cause archiver operations on them to fail. This patch adjusts the
Makefile fragments to delete the library archives before creating fresh
archives containing both the 32 bit and 64 bit shared objects.
libatomic/ChangeLog:
2020-10-11 Clement Chigot <clement.chigot@atos.net>
* config/t-aix: Delete and recreate libatomic before creating
FAT library.
libgomp/ChangeLog:
2020-10-11 Clement Chigot <clement.chigot@atos.net>
* config/t-aix: Delete and recreate libgomp before creating
FAT library.
AIX FAT libraries should be built with the version of AR chosen by configure.
The GNU Make $(AR) variable includes the AIX -X32_64 option needed
by the default Makefile rules to accept both 32 bit and 64 bit object files.
The -X32_64 option conflicts with ar archiving objects of the same name
used to build FAT libraries.
This patch changes the Makefile fragments for AIX FAT libraries to use $(AR),
but strips the -X32_64 option from the Make variable.
libgcc/ChangeLog:
2020-09-27 Clement Chigot <clement.chigot@atos.net>
* config/rs6000/t-slibgcc-aix: Use $(AR) without -X32_64.
libatomic/ChangeLog:
2020-09-27 Clement Chigot <clement.chigot@atos.net>
* config/t-aix: Use $(AR) without -X32_64.
libgomp/ChangeLog:
2020-09-27 Clement Chigot <clement.chigot@atos.net>
* config/t-aix: Use $(AR) without -X32_64.
libstdc++-v3/ChangeLog:
2020-09-27 Clement Chigot <clement.chigot@atos.net>
* config/os/aix/t-aix: Use $(AR) without -X32_64.
libgfortran/ChangeLog:
2020-09-27 Clement Chigot <clement.chigot@atos.net>
* config/t-aix: Use $(AR) without -X32_64.
Add nvptx support to libatomic.
Given that atomic_test_and_set is not implemented for nvptx (PR96964), the
compiler translates __atomic_test_and_set falling back onto the "Failing all
else, assume a single threaded environment and simply perform the operation"
case in expand_atomic_test_and_set, so it doesn't map onto an actual atomic
operation.
Still, that counts as supported for the configure test of libatomic, so we
end up with HAVE_ATOMIC_TAS_1/2/4/8/16 == 1, and the corresponding
__atomic_test_and_set_1/2/4/8/16 in libatomic all using that non-atomic
implementation.
Fix this by adding an atomic_test_and_set expansion for nvptx, that uses
libatomics __atomic_test_and_set_1.
This again makes the configure tests for HAVE_ATOMIC_TAS_1/2/4/8/16 fail, so
instead we use this case in tas_n.c:
...
/* If this type is smaller than word-sized, fall back to a word-sized
compare-and-swap loop. */
bool
SIZE(libat_test_and_set) (UTYPE *mptr, int smodel)
...
which for __atomic_test_and_set_8 uses INVERT_MASK_8.
Add INVERT_MASK_8 in libatomic_i.h, as well as MASK_8.
Tested libatomic testsuite on nvptx.
gcc/ChangeLog:
PR target/96964
* config/nvptx/nvptx.md (define_expand "atomic_test_and_set"): New
expansion.
libatomic/ChangeLog:
PR target/96898
* configure.tgt: Add nvptx.
* libatomic_i.h (MASK_8, INVERT_MASK_8): New macro definition.
* config/nvptx/host-config.h: New file.
* config/nvptx/lock.c: New file.
When compiling atomic-generic.c from the libatomic testsuite, we run into:
...
$ gcc src/libatomic/testsuite/libatomic.c/atomic-generic.c -latomic
src/libatomic/testsuite/libatomic.c/atomic-generic.c: In function ‘main’:
src/libatomic/testsuite/libatomic.c/atomic-generic.c:31:7: warning: \
implicit declaration of function ‘memcmp’ [-Wimplicit-function-declaration]
if (memcmp (&a, &zero, size))
^~~~~~
...
Fix this by adding the missing string.h include.
Tested on x86_64.
libatomic/ChangeLog:
* testsuite/libatomic.c/atomic-generic.c: Include string.h.
The FAT libraries config fragments need to know which library is native
and which is a multilib to choose the correct multilib from which to
append the additional object file or shared object file. Testing the
top-level archive is fragile because it will fail if rebuilding. This
patch tests the compiler preprocessing macros for the 64 bit AIX specific
__64BIT__ to determine the native mode of the compiler in MULTILIBTOP.
2020-07-14 David Edelsohn <dje.gcc@gmail.com>
libatomic/ChangeLog
* config/t-aix: Set BITS from compiler cpp macro.
libgcc/ChangeLog
* config/rs6000/t-slibgcc-aix: Set BITS from compiler cpp macro.
libgfortran/ChangeLog
* config/t-aix: Set BITS from compiler cpp macro.
libgomp/ChangeLog
* config/t-aix: Set BITS from compiler cpp macro.
libstdc++-v3/ChangeLog
* config/os/aix/t-aix: Set BITS from compiler cpp macro.
Automake and GNU Make both use the endif keyword, which conflicts and
elicits an error for matching if/ifdef and endif.
This patch changes the conditional include to use "-include" to prevent
a warning about a possible empty tmake_file.
libgomp/ChangeLog
2020-06-22 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am: Use -include.
* Makefile.in: Regenerate.
libatomic/ChangeLog
2020-06-22 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am: Use -include.
* Makefile.in: Regenerate.
libstdc++-v3/ChangeLog
2020-06-22 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am: Use -include.
* Makefile.in: Regenerate.
libgfortran/ChangeLog
2020-06-22 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am: Use -include.
* Makefile.in: Regenerate.
This patch adds the ability to configure GCC on AIX to build as a
64 bit application and to build target libraries "FAT" libraries in both
32 bit and 64 bit mode.
The patch adds makefile fragment hooks to target libraries that allows
them to include target-specific rules. The target specific rules for
AIX place both 32 bit and 64 bit objects and shared objects
in archives at the top-level, not multilib subdirectories. The
multilibs are built in subdirectories, but must be combined during the
last parts of the target library build process. Because of the way
that GCC bootstrap works, the libraries must be combined during the
multiple stages of GCC bootstrap, not solely when installed in the
final destination, so the libraries are correct at the end of
each target library build stage, not solely an install recipe.
gcc/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* config.gcc: Use t-aix64, biarch64 and default64 for cpu_is_64bit.
* config/rs6000/aix72.h (ASM_SPEC): Remove aix64 option.
(ASM_SPEC32): New.
(ASM_SPEC64): New.
(ASM_CPU_SPEC): Remove vsx and altivec options.
(CPP_SPEC_COMMON): Rename from CPP_SPEC.
(CPP_SPEC32): New.
(CPP_SPEC64): New.
(CPLUSPLUS_CPP_SPEC): Rename to CPLUSPLUS_CPP_SPEC_COMMON..
(TARGET_DEFAULT): Only define if not BIARCH.
(LIB_SPEC_COMMON): Rename from LIB_SPEC.
(LIB_SPEC32): New.
(LIB_SPEC64): New.
(LINK_SPEC_COMMON): Rename from LINK_SPEC.
(LINK_SPEC32): New.
(LINK_SPEC64): New.
(STARTFILE_SPEC): Add 64 bit version of crtcxa and crtdbase.
(ASM_SPEC): Define 32 and 64 bit alternatives using DEFAULT_ARCH64_P.
(CPP_SPEC): Same.
(CPLUSPLUS_CPP_SPEC): Same.
(LIB_SPEC): Same.
(LINK_SPEC): Same.
(SUBTARGET_EXTRA_SPECS): Add new 32/64 specs.
* config/rs6000/defaultaix64.h: New file.
* config/rs6000/t-aix64: New file.
libgcc/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* config.host (extra_parts): Add crtcxa_64 and crtdbase_64.
* config/rs6000/t-aix-cxa: Explicitly compile 32 bit with -maix32
and 64 bit with -maix64.
* config/rs6000/t-slibgcc-aix: Remove extra @multilib_dir@ level.
Build and install AIX-style FAT libraries.
libgomp/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am (tmake_file): Build and install AIX-style FAT libraries.
* Makefile.in: Regenerate
* configure.ac (tmake_file): Substitute.
* configure: Regenerate.
* configure.tgt (powerpc-ibm-aix*): Define tmake_file.
* config/t-aix: New file.
libstdc++-v3/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am (tmake_file): Build and install AIX-style FAT libraries.
* Makefile.in: Regenerate.
* configure.ac (tmake_file): Substitute.
* configure: Regenerate.
* configure.host (aix*): Define tmake_file.
* config/os/aix/t-aix: New file.
libatomic/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am (tmake_file): Build and install AIX-style FAT libraries.
* Makefile.in: Regenerate.
* configure.ac (tmake_file): Substitute.
* configure: Regenerate.
* configure.tgt (powerpc-ibm-aix*): Define tmake_file.
* config/t-aix: New file.
libgfortran/ChangeLog
2020-06-21 David Edelsohn <dje.gcc@gmail.com>
* Makefile.am (tmake_file): Build and install AIX-style FAT libraries.
* Makefile.in: Regenerate.
* configure.ac (tmake_file): Substitute.
* configure: Regenerate.
* configure.host: Add system configury stanza. Define tmake_file.
* config/t-aix: New file.
Windows ABI (MinGW) is different than Linux ABI when bitfileds are involved.
The following patch adds __attribute__ ((gcc_struct)) to struct fenv in order
to match the layout of x87 state image in memory.
2020-06-01 Uroš Bizjak <ubizjak@gmail.com>
libatomic/ChangeLog:
* config/x86/fenv.c (struct fenv): Add __attribute__ ((gcc_struct)).
libgcc/ChangeLog:
* config/i386/sfp-exceptions.c (struct fenv):
Add __attribute__ ((gcc_struct)).
libgfortran/ChangeLog:
PR libfortran/95418
* config/fpu-387.h (struct fenv): Add __attribute__ ((gcc_struct)).
Introduce math_force_eval_div to use generic division to generate
INEXACT as well as INVALID and DIVZERO exceptions.
libgcc/ChangeLog:
* config/i386/sfp-exceptions.c (__math_force_eval): Remove.
(__math_force_eval_div): New define.
(__sfp_handle_exceptions): Use __math_force_eval_div to use
generic division to generate INVALID, DIVZERO and INEXACT
exceptions.
libatomic/ChangeLog:
* config/x86/fenv.c (__math_force_eval): Remove.
(__math_force_eval_div): New define.
(__atomic_deraiseexcept): Use __math_force_eval_div to use
generic division to generate INVALID, DIVZERO and INEXACT
exceptions.
libgfortran/ChangeLog:
* config/fpu-387.h (__math_force_eval): Remove.
(__math_force_eval_div): New define.
(local_feraiseexcept): Use __math_force_eval_div to use
generic division to generate INVALID, DIVZERO and INEXACT
exceptions.
(struct fenv): Define named struct instead of typedef.
Introduce math_force_eval to evaluate generic division to generate
INVALID and DIVZERO exceptions.
libgcc/ChangeLog:
* config/i386/sfp-exceptions.c (__math_force_eval): New define.
(__sfp_handle_exceptions): Use __math_force_eval to evaluete
generic division to generate INVALID and DIVZERO exceptions.
libatomic/ChangeLog:
* config/x86/fenv.c (__math_force_eval): New define.
(__atomic_feraiseexcept): Use __math_force_eval to evaluete
generic division to generate INVALID and DIVZERO exceptions.
libgfortran/ChangeLog:
* config/fpu-387.h (__math_force_eval): New define.
(local_feraiseexcept): Use __math_force_eval to evaluete
generic division to generate INVALID and DIVZERO exceptions.
According to "Intel 64 and IA32 Arch SDM, Vol. 3:
"Because SIMD floating-point exceptions are precise and occur immediately,
the situation does not arise where an x87 FPU instruction, a WAIT/FWAIT
instruction, or another SSE/SSE2/SSE3 instruction will catch a pending
unmasked SIMD floating-point exception."
Remove unneeded assignments to volatile memory.
libgcc/ChangeLog:
* config/i386/sfp-exceptions.c (__sfp_handle_exceptions) [__SSE_MATH__]:
Remove unneeded assignments to volatile memory.
libatomic/ChangeLog:
* config/x86/fenv.c (__atomic_feraiseexcept) [__SSE_MATH__]:
Remove unneeded assignments to volatile memory.
libgfortran/ChangeLog:
* config/fpu-387.h (local_feraiseexcept) [__SSE_MATH__]:
Remove unneeded assignments to volatile memory.
Fix a problem with the libatomic testsuite using a method to determine
the compiler to use resulting in the tool being different from one the
library has been built with, and causing a catastrophic failure from the
lack of a suitable `--sysroot=' option where the `--with-build-sysroot='
configuration option has been used to build the compiler resulting in
the inability to link executables.
Address this problem by providing a DejaGNU configuration file defining
the compiler to use, via the GCC_UNDER_TEST TCL variable, set from $CC
by autoconf, which will have all the required options set for the target
compiler to build executables in the environment configured, removing
failures like:
.../bin/riscv64-linux-gnu-ld: cannot find crt1.o: No such file or directory
.../bin/riscv64-linux-gnu-ld: cannot find -lm
collect2: error: ld returned 1 exit status
compiler exited with status 1
FAIL: libatomic.c/atomic-compare-exchange-1.c (test for excess errors)
Excess errors:
.../bin/riscv64-linux-gnu-ld: cannot find crt1.o: No such file or directory
.../bin/riscv64-linux-gnu-ld: cannot find -lm
UNRESOLVED: libatomic.c/atomic-compare-exchange-1.c compilation failed to produce executable
and bringing overall test results for the `riscv64-linux-gnu' target
(here with the `x86_64-linux-gnu' host and RISC-V QEMU in the Linux user
emulation mode as the target board) from:
=== libatomic Summary ===
# of unexpected failures 27
# of unresolved testcases 27
to:
=== libatomic Summary ===
# of expected passes 54
libatomic/
* configure.ac: Add testsuite/libatomic-site-extra.exp to output
files.
* configure: Regenerate.
* libatomic/testsuite/libatomic-site-extra.exp.in: New file.
* testsuite/Makefile.am (EXTRA_DEJAGNU_SITE_CONFIG): New
variable.
* testsuite/Makefile.in: Regenerate.
2020-02-22 Jakub Jelinek <jakub@redhat.com>
PR other/55930
* Makefile.am (M_DEPS): Guard the empty definition with
@AMDEP_FALSE@ rather than @AMDEP_TRUE@.
* Makefile.in: Regenerated.
