Inline flowgraphs only for call-sites for which there was a minimal number of calls during an instrumented run of the program. Callee flowgraphs are considered candidates based on a weight heuristic like for basic inlining. (see --translation-backendopt-inline, --prof-based-inline-threshold ).
The option takes as value a string which is the arguments to pass to the program for the instrumented run.
This optimisation is not used by default.