We are trying to use -finstrument-functions to do some custom profiling on x86 and ppc.
For normal code execution, it works fine, calling our entry and exit methods as expected. Unfortunately, we are running into problems related to exceptions. If we exit a function because of an exception, no exit method is called. This greatly diminishes the usefulness of the instrumentation since we are no longer guaranteed to get matching entry and exit calls. It seems to me that if function instrumentation is enabled, then the compiler should guarantee that exit (or perhaps a exit_throw?) is called, even if the function is exited because of an exception. I can see where the current instrumentation is added in gcc/function.c. Is there some easy way to add some cleanup code that guarantees exit will be called? Are there any documents on how RTL works? Another possible place I see to hook it in is unwind.inc, but that does not have access to the current function tree, so we can't tell if instrumentation is enabled or not. Thank you, - Chris Kirby
