Software optimization gaining by middle-end compiler phase-ordering: actual state and directions

The report is devoted to the actual state and problems of software optimization using compiler auto-tuning approaches with middle-end optimization phase-ordering. First of all, the main methodics and entities of this technical research field will be covered, such as tasks formulation, optimization space of passes exploration, passes ordering, decision-making and software characterization approaches, benchmarks collection methodics, etc. Finally, some results of author's research group investigation in construction of modern approach for phase-ordering on the top of GCC for optimization under mixed criteria will be reported.