Generating user-defined function calls in RTL

[qubits]

Hello everyone,
I want the compiler to call one of my functions when
it is generating RTL for tree expressions. For this I
need to 'emit' a function call stub into the code
generated so that the my function is called during
program run-time. Is it possible to do something like
this in GCC?
I have been struggling with this for sometime now. 
Any suggestions would be wonderful!

Thanks,
q.


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