Combined profiling
Paul Berube, Adam Preuss, José Nelson Amaral · 2011
Feedback-directed optimization (FDO) depends on profiling information that is representative of a typical execution of a given application. For most applications of interest, multiple data inputs need to be used to characterize the typical behavior of the program. Thus, profiling information from multiple runs of the program needs to be combined. We are working on a new methodology to produce statistically sound combined profiles from multiple runs of a program. This paper presents the motivation for combined profiling (CP), the requirements for a practical and useful methodology to combine profiles, and introduces the principal ideas under development for the creation of this methodology. We are currently working on implementations of CP in both the LLVM compiler and the IBM XL suite of compilers.