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2022-08-08AArch32: Fix 128-bit sequential consistency atomic operations.Tamar Christina1-0/+19
Similar to AArch64 the Arm implementation of 128-bit atomics is broken. For 128-bit atomics we rely on pthread barriers to correct guard the address in the pointer to get correct memory ordering. However for 128-bit atomics the address under the lock is different from the original pointer. This means that one of the values under the atomic operation is not protected properly and so we fail during when the user has requested sequential consistency as there's no barrier to enforce this requirement. As such users have resorted to adding an #ifdef GCC <emit barrier> #endif around the use of these atomics. This corrects the issue by issuing a barrier only when __ATOMIC_SEQ_CST was requested. I have hand verified that the barriers are inserted for atomic seq cst. libatomic/ChangeLog: PR target/102218 * config/arm/host-config.h (pre_seq_barrier, post_seq_barrier, pre_post_seq_barrier): Require barrier on __ATOMIC_SEQ_CST.
2022-08-08AArch64: Fix 128-bit sequential consistency atomic operations.Tamar Christina2-0/+69
The AArch64 implementation of 128-bit atomics is broken. For 128-bit atomics we rely on pthread barriers to correct guard the address in the pointer to get correct memory ordering. However for 128-bit atomics the address under the lock is different from the original pointer. This means that one of the values under the atomic operation is not protected properly and so we fail during when the user has requested sequential consistency as there's no barrier to enforce this requirement. As such users have resorted to adding an #ifdef GCC <emit barrier> #endif around the use of these atomics. This corrects the issue by issuing a barrier only when __ATOMIC_SEQ_CST was requested. To remedy this performance hit I think we should revisit using a similar approach to out-line-atomics for the 128-bit atomics. Note that I believe I need the empty file due to the include_next chain but I am not entirely sure. I have hand verified that the barriers are inserted for atomic seq cst. libatomic/ChangeLog: PR target/102218 * config/aarch64/aarch64-config.h: New file. * config/aarch64/host-config.h: New file.
2022-03-17libatomic: Improve 16-byte atomics on Intel AVX [PR104688]Jakub Jelinek2-7/+48
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.
2022-01-03Update copyright years.Jakub Jelinek19-19/+19
2021-07-21Adjust macro to avoid warning [PR101379].Martin Sebor1-1/+7
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.
2021-01-04Update copyright years.Jakub Jelinek19-19/+19
2020-10-11aix: remove libgomp and libatomic archives before creating FAT archivesClément Chigot1-0/+3
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.
2020-09-27aix: Use $(AR) without -X32_64 to build FAT libraries.Clément Chigot1-2/+3
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.
2020-09-11[libatomic] Add nvptx supportTom de Vries2-0/+112
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.
2020-07-14aix: FAT libraries: test native compiler mode directlyDavid Edelsohn1-1/+1
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.
2020-06-21aix: Add GCC64 configuration and FAT target libraries.David Edelsohn1-0/+10
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.
2020-06-01i386: Add __attribute__ ((gcc_struct)) to struct fenv [PR95418]Uros Bizjak1-1/+1
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)).
2020-05-06i386: Use generic division to generate INEXACT exceptionUros Bizjak1-13/+9
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.
2020-05-01i386: Use generic division to generate INVALID and DIVZERO exceptionsUros Bizjak1-12/+8
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.
2020-04-19i386: Remove unneeded assignments when triggering SSE exceptionsUros Bizjak1-6/+0
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.
2020-01-01Update copyright years.Jakub Jelinek17-17/+17
From-SVN: r279813
2019-01-01Update copyright years.Jakub Jelinek17-17/+17
From-SVN: r267494
2018-06-21[ARM] Use __ARM_ARCH and __ARM_FEATURE_LDREX instead of __ARM_ARCH__Christophe Lyon1-47/+5
2018-06-21 Christophe Lyon <christophe.lyon@linaro.org> libatomic/ * config/arm/arm-config.h (__ARM_ARCH__): Remove definitions, use __ARM_ARCH instead. Use __ARM_FEATURE_LDREX to define HAVE_STREX and HAVE_STREXBHD libgcc/ * config/arm/lib1funcs.S (__ARM_ARCH__): Remove definitions, use __ARM_ARCH and __ARM_FEATURE_CLZ instead. (HAVE_ARM_CLZ): Remove definition, use __ARM_FEATURE_CLZ instead. * config/arm/ieee754-df.S: Use __ARM_FEATURE_CLZ instead of __ARM_ARCH__. * config/arm/ieee754-sf.S: Likewise. * config/arm/libunwind.S: Use __ARM_ARCH instead of __ARM_ARCH__. From-SVN: r261841
2018-05-23x86: libatomic: Do not assume ELF constructors run before IFUNC resolversFlorian Weimer2-9/+39
PR libgcc/60790 x86: Do not assume ELF constructors run before IFUNC resolvers. * config/x86/host-config.h (libat_feat1_ecx, libat_feat1_edx): Remove declarations. (__libat_feat1, __libat_feat1_init): Declare. (FEAT1_REGISTER): Define. (load_feat1): New function. (IFUNC_COND_1): Adjust. * config/x86/init.c (libat_feat1_ecx, libat_feat1_edx) (init_cpuid): Remove definitions. (__libat_feat1): New variable. (__libat_feat1_init): New function. From-SVN: r260603
2018-03-09S/390: libatomic: Fix 16 byte atomic exchangeAndreas Krebbel1-0/+69
The compiler builtin will use the hardware instruction cdsg if the memory operand is properly aligned and will fall back to the library call otherwise. In case the compiler for one part is able to detect that the location is aligned and fails to do so for another usage of the hw instruction and the sw fall back would be mixed on the same memory location. To avoid this the library fall back also has to use the hardware instruction if possible. libatomic/ChangeLog: 2018-03-09 Andreas Krebbel <krebbel@linux.vnet.ibm.com> * config/s390/exch_n.c: New file. * configure.tgt: Add the config directory for s390. From-SVN: r258384
2018-01-03Update copyright years.Jakub Jelinek16-16/+16
From-SVN: r256169
2017-12-05Makefile.am (ARCH_AARCH64_LINUX): Add IFUNC_OPTIONS and libatomic_la_LIBADD.Steve Ellcey1-0/+36
2017-12-04 Steve Ellcey <sellcey@cavium.com> * Makefile.am (ARCH_AARCH64_LINUX): Add IFUNC_OPTIONS and libatomic_la_LIBADD. * config/linux/aarch64/host-config.h: New file. * configure.ac (IFUNC_RESOLVER_ARGS): Define. (ARCH_AARCH64_LINUX): New conditional for IFUNC builds. * configure.tgt (aarch64): Set ARCH and try_ifunc. (aarch64*-*-linux*) Update config_path. (aarch64*-*-linux*) Set IFUNC_RESOLVER_ARGS. * libatomic_i.h (GEN_SELECTOR): Add IFUNC_RESOLVER_ARGS argument. * Makefile.in: Regenerate. * auto-config.h.in: Regenerate. * configure: Regenerate. From-SVN: r255399
2017-02-01Fix __atomic to not implement atomic loads with CAS.Torvald Riegel1-0/+18
gcc/ * builtins.c (fold_builtin_atomic_always_lock_free): Make "lock-free" conditional on existance of a fast atomic load. * optabs-query.c (can_atomic_load_p): New function. * optabs-query.h (can_atomic_load_p): Declare it. * optabs.c (expand_atomic_exchange): Always delegate to libatomic if no fast atomic load is available for the particular size of access. (expand_atomic_compare_and_swap): Likewise. (expand_atomic_load): Likewise. (expand_atomic_store): Likewise. (expand_atomic_fetch_op): Likewise. * testsuite/lib/target-supports.exp (check_effective_target_sync_int_128): Remove x86 because it provides no fast atomic load. (check_effective_target_sync_int_128_runtime): Likewise. libatomic/ * acinclude.m4: Add #define FAST_ATOMIC_LDST_*. * auto-config.h.in: Regenerate. * config/x86/host-config.h (FAST_ATOMIC_LDST_16): Define to 0. (atomic_compare_exchange_n): New. * glfree.c (EXACT, LARGER): Change condition and add comments. From-SVN: r245098
2017-01-30[ARM][PR target/78945] Fix libatomic on armv7-mSzabolcs Nagy1-2/+2
ARM libatomic inline asm uses sel, uadd8, uadd16 instructions which are only available if __ARM_FEATURE_SIMD32 is defined. libatomic/ 2017-01-30 Szabolcs Nagy <szabolcs.nagy@arm.com> PR target/78945 * config/arm/exch_n.c (libat_exchange): Check __ARM_FEATURE_SIMD32. From-SVN: r245023
2017-01-01Update copyright years.Jakub Jelinek15-15/+15
From-SVN: r243994
2016-05-10[libatomic] Add missing files for RTEMS supportSebastian Huber2-0/+78
Add missing files for: 2016-04-27 Sebastian Huber <sebastian.huber@embedded-brains.de> * configure.tgt (configure_tgt_pre_target_cpu_XCFLAGS): New variable. (*-*-rtems*): New supported target. * config/rtems/host-config.h: New file. * config/rtems/lock.c: Likewise. From-SVN: r236060
2016-01-04Update copyright years.Jakub Jelinek13-13/+13
From-SVN: r232055
2015-01-05Update copyright years.Jakub Jelinek13-13/+13
From-SVN: r219188
2014-06-17Makefile.am (libatomic_la_LDFLAGS): Add lt_host_flags.Kai Tietz2-0/+178
* Makefile.am (libatomic_la_LDFLAGS): Add lt_host_flags. * configure.ac (ACX_LT_HOST_FLAGS): New. (target_thread_file): New. * configure.tgt (mingw): Add mingw support. * config/mingw/host-config.h: New file. * config/mingw/lock.c: Likewise. * Makefile.in: Regenerated. * configure: Likewise. * aclocal.m4: Likewise. * testsuite/Makefile.in: Likewise. From-SVN: r211747
2014-01-02Update copyright years in libatomic/Richard Sandiford11-11/+11
From-SVN: r206291
2013-12-09sfp-exceptions.c (__sfp_handle_exceptions): Emit SSE instructions when ↵Uros Bizjak1-3/+3
__TARGET_SSE__ is defined. libgcc/ChangeLog: 2013-12-09 Uros Bizjak <ubizjak@gmail.com> * config/i386/sfp-exceptions.c (__sfp_handle_exceptions): Emit SSE instructions when __TARGET_SSE__ is defined. libatomic/ChangeLog: 2013-12-09 Uros Bizjak <ubizjak@gmail.com> * config/x86/fenv.c (__atomic_feraiseexcept): Emit SSE instructions when __TARGET_SSE__ is defined. From-SVN: r205811
2013-11-10fenv.c: New file.Uros Bizjak1-0/+116
* config/x86/fenv.c: New file. From-SVN: r204634
2013-01-14Update copyright years in libatomic.Richard Sandiford10-10/+10
From-SVN: r195164
2012-12-04libatomic: Detect and build for ARM architecture armv8-a.Marcus Shawcroft1-0/+4
2012-12-04 Marcus Shawcroft <marcus.shawcroft@arm.com> * config/arm/arm-config.h (__ARM_ARCH_8A__): New. From-SVN: r194150
2012-05-01Add libatomic as a target library.Richard Henderson13-0/+810
From-SVN: r187018