Translate function addresses to filenames.

This patch builds upon the previous commit
[de8b5245e76c758ca9ac5ad471c7310f5bf883be / Print function names and line
numbers in recommendations] to display filenames and line numbers instead of
function names. This change will be used in printing the recommendation output
in a format that will be easy to parse by a program (especially, the
vectorization-opportunities code).