From 8cacb9c7351087b8072e424c4db0eabfd2cbf1c6 Mon Sep 17 00:00:00 2001 From: henry Date: Mon, 22 Nov 2004 10:28:36 +0000 Subject: [PATCH] check for __builtin_expect (used by libmpeg2) git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@14015 b3059339-0415-0410-9bf9-f77b7e298cf2 --- configure | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/configure b/configure index efad5d2507..d5ac8632aa 100755 --- a/configure +++ b/configure @@ -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 @@ -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))