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3b5ebe85aa
This patch removes the arch-specific atomic instruction, relying on compiler builtins. The __sparc32_atomic_locks support is removed and a configure check is added to check if compiler uses libatomic to implement CAS. It also removes the sparc specific sem_* and pthread_barrier_* implementations. It in turn allows buidling against a LEON3/LEON4 sparcv8 target, although it will still be incompatible with generic sparcv9. Checked on sparcv9-linux-gnu and sparc64-linux-gnu. I also checked with build against sparcv8-linux-gnu with -mcpu=leon3. Tested-by: Andreas Larsson <andreas@gaisler.com>
38 lines
1.4 KiB
Plaintext
38 lines
1.4 KiB
Plaintext
GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
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# Local configure fragment for sysdeps/sparc/sparc32
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# Test if compiler targets at least sparcv8.
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AC_CACHE_CHECK([for at least sparcv8 support],
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[libc_cv_sparcv8],
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[AC_EGREP_CPP(yes,[#if defined (__sparc_v8__) || defined (__sparc_v9__)
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yes
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#endif
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], libc_cv_sparcv8=yes, libc_cv_sparcv8=no)])
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if test $libc_cv_sparcv8 = no; then
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AC_MSG_ERROR([no support for pre-v8 sparc])
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fi
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# Test if compiler generates external calls to libatomic for CAS operation.
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# It is suffice to check for int only and the test is similar of C11
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# atomic_compare_exchange_strong using GCC builtins.
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AC_CACHE_CHECK(for external libatomic calls,
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libc_cv_cas_uses_libatomic,
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[cat > conftest.c <<EOF
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_Bool foo (int *ptr, int *expected, int desired)
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{
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return __atomic_compare_exchange_n (ptr, expected, desired, 0,
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__ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);
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}
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EOF
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libc_cv_cas_uses_libatomic=no
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if AC_TRY_COMMAND(${CC-cc} -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
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if grep '__atomic_compare_exchange_4' conftest.s >/dev/null; then
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libc_cv_cas_uses_libatomic=yes
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fi
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fi
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rm -f conftest.c conftest.s
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])
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if test $libc_cv_cas_uses_libatomic = yes; then
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AC_MSG_ERROR([external dependency of libatomic is not supported])
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fi
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