3.5.14 How Do I Know Which Resources Are Being Used by Each Function?

In the assembly list file there is information printed for every C function, including library functions (see 6.3 Assembly List Files). This information indicates what registers the function used, what functions it calls (this is also found in the call graph; see 6.3.6 Call Graph and how many bytes of data memory it requires. Note that auto, parameter and temporary variables used by a function can overlap with those from other functions as these are placed in a compiled stack by the compiler (see 5.4.2.2 Automatic Storage Duration Objects).