------- Comment #5 from ubizjak at gmail dot com 2009-08-10 08:05 ------- (In reply to comment #4)
> If you want to change it to be consistent with the documentation (not with > existing implementation) and pass structures always on stack, I wouldn't > object > against it. Just don't change it later. > IMO, regparm ABI should be documented in i386 psABI first [1], so we will have something to implement against. As it stands now, regparm is mainly internal to gcc, so non-exported functions can be called more efficiently. So, everything is OK as long as the caller and the callee agree on the location of arguments. OTOH, if regparm is documented, we can implement alternative function entry points, so exported functions will also benefit from regparm ABI. See how ICC handles this. [1] http://groups-beta.google.com/group/ia32-abi -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41017