[GENERAL] stored procedure code

[Derek Perak]

Hi, I would like to learn about how stored procedures are handled in postgres. 
In particular, I'd like to learn how plpgsql procedures are compiled and 
stored, and how they (both plpgsql and C procedures) interact with the 
optimizer during planning. Would appreciate if someone can point out some links 
to the source code for me to check out.
Thanks!Derek