PRUNTIME_FUNCTION
RtlLookupFunctionEntry(
  IN  ULONG ControlPc
  );

Routine Description:

    This function searches the currently active function tables for an entry
    that corresponds to the specified PC value.

Arguments:

    ControlPc - Supplies the address of an instruction within the specified
        function.

Return Value:

    If there is no entry in the function table for the specified PC, then
    NULL is returned. Otherwise, the address of the function table entry
    that corresponds to the specified PC is returned.