diff options
-rwxr-xr-x | configure | 22 |
1 files changed, 22 insertions, 0 deletions
@@ -2309,6 +2309,25 @@ else fi +echocheck "__builtin_expect" +# GCC branch prediction hint +cat > $TMPC << EOF +int foo (int a) { + a = __builtin_expect (a, 10); + return a == 10 ? 0 : 1; +} +int main() { return foo(10) && foo(0); } +EOF +_builtin_expect=no +cc_check && _builtin_expect=yes +if test "$_builtin_expect" = yes ; then + _def_builtin_expect='#define HAVE_BUILTIN_EXPECT 1' +else + _def_builtin_expect='#undef HAVE_BUILTIN_EXPECT' +fi +echores "$_builtin_expect" + + echocheck "kstat" cat > $TMPC << EOF #include <kstat.h> @@ -6672,6 +6691,9 @@ $_def_dynamic_plugins /* "restrict" keyword */ $_def_restrict_keyword +/* __builtin_expect branch prediction hint */ +$_def_builtin_expect + /* attribute(used) as needed by some compilers */ #if (__GNUC__ * 100 + __GNUC_MINOR__ >= 300) # define attribute_used __attribute__((used)) |