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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-11-12 19:11:10 +0000 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-11-27 10:31:13 -0300 |
| commit | 3b5ebe85aabfa44583a18a7ef51bc4d387e362c1 (patch) | |
| tree | 8853a1bcbe48f93c1e696ae89e503922845c6e8c /sysdeps/sparc/sparc32/configure | |
| parent | 5d9b7b9fa734c5381e0295c85c0e40520d9f6063 (diff) | |
| download | glibc-3b5ebe85aabfa44583a18a7ef51bc4d387e362c1.tar.gz glibc-3b5ebe85aabfa44583a18a7ef51bc4d387e362c1.tar.xz glibc-3b5ebe85aabfa44583a18a7ef51bc4d387e362c1.zip | |
sparc: Use atomic compiler builtins on sparc
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>
Diffstat (limited to 'sysdeps/sparc/sparc32/configure')
| -rw-r--r-- | sysdeps/sparc/sparc32/configure | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc32/configure b/sysdeps/sparc/sparc32/configure index d7f16b1de0..b6ec0e7d8f 100644 --- a/sysdeps/sparc/sparc32/configure +++ b/sysdeps/sparc/sparc32/configure @@ -160,3 +160,38 @@ $as_echo "$libc_cv_sparcv8" >&6; } if test $libc_cv_sparcv8 = no; then as_fn_error $? "no support for pre-v8 sparc" "$LINENO" 5 fi + +# Test if compiler generates external calls to libatomic for CAS operation. +# It is suffice to check for int only and the test is similar of C11 +# atomic_compare_exchange_strong using GCC builtins. +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for external libatomic calls" >&5 +$as_echo_n "checking for external libatomic calls... " >&6; } +if ${libc_cv_cas_uses_libatomic+:} false; then : + $as_echo_n "(cached) " >&6 +else + cat > conftest.c <<EOF + _Bool foo (int *ptr, int *expected, int desired) + { + return __atomic_compare_exchange_n (ptr, expected, desired, 0, + __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); + } +EOF + libc_cv_cas_uses_libatomic=no + if { ac_try='${CC-cc} -S conftest.c -o conftest.s 1>&5' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; }; then + if grep '__atomic_compare_exchange_4' conftest.s >/dev/null; then + libc_cv_cas_uses_libatomic=yes + fi + fi + rm -f conftest.c conftest.s + +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_cas_uses_libatomic" >&5 +$as_echo "$libc_cv_cas_uses_libatomic" >&6; } +if test $libc_cv_cas_uses_libatomic = yes; then + as_fn_error $? "external dependency of libatomic is not supported" "$LINENO" 5 +fi |