However, statically analysing low level program structures is hard, and the gap between the high-level program structure and the low-level energy models needs to be bridged. We have developed a tool for performing a static analysis on the intermediate compiler representations of a program. Specifically, we target LLVM IR, a representation used by most modern
compilers including Clang.
One of the challenges in doing so is that of determining an energy cost of executing LLVM IR program segments, for which we have developed a mapping tool. This tool associates LLVM IR program segments with assembly program segments, producing a mapping. Mapping information is useful when performing an analysis at one layer using energy models defined at a lower layer.
Essentially, this propagates the energy model defined at the instruction set
level up to the LLVM IR level, at which the analysis is performed. When this is
used with our analysis tool, we are able to infer energy formulae that
characterize the energy consumption for a particular program. This approach can
be applied to any languages targeting the LLVM toolchain or architectures
supported by LLVM.
Static energy estimation has applications in program optimization, and enables
energy-aware software development.