How Could Compile-Time Program Analysis help Leveraging Emerging NVM Features?

International audienceBeyond the fact of generating machine code, compilers play a critical role in delivering high performance, and more recently high energy efficiency. For decades, the memory technology of target systems has consisted in SRAM at cache level, and DRAM for main memory. Emerging non-volatile memories (NVMs) open up new opportunities, along with new design challenges. In particular, the asymmetric cost of read/write accesses calls for adjusting existing techniques in order to efficiently exploit NVMs. In addition, this technology makes it possible to design memories with cheaper accesses at the cost of lower data retention times. These features can be exploited at compile time to derive better data mappings according to the application and data retention characteristics. We review a number of compile-time analysis and optimization techniques, and how they could apply to systems in presence of NVMs. In particular, we consider the case of the reduction of the number of writes, and the analysis of variables lifetime for memory bank assignment of program variables