Add configure tests for Intel atomic intrinsics
diff --git a/configure.ac b/configure.ac
index d126b16..2fb058f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -177,6 +177,23 @@
fi
AM_CONDITIONAL(HAVE_UNISCRIBE, $have_uniscribe)
+dnl ===========================================================================
+
+AC_CACHE_CHECK([for Intel atomic primitives], hb_cv_have_intel_atomic_primitives, [
+ hb_cv_have_intel_atomic_primitives=false
+ AC_TRY_LINK([], [
+ void memory_barrier (void) { __sync_synchronize (); }
+ int atomic_add (int i) { return __sync_fetch_and_add (&i, 1); }
+ int atomic_cmpxchg (int *i, int *j, int *k) { return __sync_bool_compare_and_swap (&i, j, k); }
+ ], hb_cv_have_intel_atomic_primitives=true
+ )
+])
+if $hb_cv_have_intel_atomic_primitives; then
+ AC_DEFINE(HAVE_INTEL_ATOMIC_PRIMITIVES, 1, [Have Intel __sync_* atomic primitives])
+fi
+
+dnl ===========================================================================
+
AC_CONFIG_FILES([
Makefile
harfbuzz.pc
