File needs to be unique within the same load module
File needs to be unique within the same load module

We want to have different file ID for the same filename from different load module (otherwise it confuses hpcviewer).
To ensure uniqueness, we need to have a tuple <load_module, file_name> as the key instead of just the filename.

HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit