noinline, forceinline, builtin_expect

[Martin Nowak via Digitalmars-d]

I'm currently working on optimizing the GC marking code and I'm 
having quite some problems with the inline decisions of the 
compiler.
The compiler can't make good decisions here, because it lacks 
information about which branches are executed rarely.
Would be nice to have @noinline, @forceinline and 
__builtin_expect.