This updates -mcount to use the new attribute names, and switches over -finstrument-functions to also use these attributes rather than inserting instrumentation in the frontend.
It also adds a new flag, -finstrument-functions-after-inlining, which makes the cygprofile instrumentation get inserted after inlining rather than before.
This actually describes GCC's behavior for -finstrument-functions. I suspect the current behavior is pretty useless for most people. I'd rather make the new behavior the default and add a flag to request the old behavior.