------- Comment #9 from hubicka at gcc dot gnu dot org 2007-02-21 17:26 ------- The main problem here is that inliner really don't have enough of detailed information. In general inlining improves optimization and often leads to smaller code when inlining such a trivial function ARM or not. Clearly the outcome depends on function, on the context it is called in and on the target platform and on the other optimizations enabled but basically only function body in very rought way is considered when making inlining decisions.
I don't see that adding a hook to provide target specific tuning for size estimates at this level is going to be useful enough to justify maintenance cost of such code. Sadly inlining heuristics is one of the most important and least informed parts of optimization queue. Honza PS: In your testcase x86-64 will pass in register and won't need stack frame either. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30908
