On 2012年03月16日 23:23, Dave Hylands wrote:
Hi Bill,
On Thu, Mar 15, 2012 at 11:52 PM, bill4carson<bill4carson@gmail.com> wrote:
Hi, All
The question is simple.
func_a {
call func_b }
func_b {
call func_c }
func_c {
return to func_a }
The compiler I use let func_c to return func_a directly, IOW when func_b calls func_c, it use JUMP, other JUMP and LINK, and it's definitely not a question about inline or noinline.
So can I ask why how to let the compiler use JUMP and LINK when func_b calls func_c?
This is called Tail Optimization. See http://c2.com/cgi/wiki?TailCallOptimization
gcc (I'm using 4.4.4) with -O3 does this.
Thanks for the information.
If it's not the right place to post this, sorry for the noise.
The kernel newbies list is probably not the right place (since this has nothing to do with the kernel). It also has nothing to do with binutils. It's a gcc optimization, so picking a gcc list would probably be more appropriate.
-- I am a slow learner but I will keep trying to fight for my dreams! --bill