Hey, you could also check this site to just add a new optimization pass ... http://gcc.gnu.org/wiki/WritingANewPass Andi > Hello, > > Can we *add* our own SSA *optimizations* *passes* *to* *GCC*? Yes. > is *there* a plugin or API that can help doing this ? (since *GCC* is open > source) *to* run this *optimization*, can we easialy *add* it *to* other > *optimizations* performed by chosing one of *the* known *GCC* flag: O1, O2, ... As of *GCC* 4.5 (which isn't yet released - you'd need *to* build from svn), *there* is a plugin API. See http://*gcc*.gnu.org/onlinedocs/*gccint*/Plugins.html#Plugins <http://gcc.gnu.org/onlinedocs/gccint/Plugins.html#Plugins> Brad