Minimizing embedded software power consumption through reduction of data memory access

Software applications that involve multimedia signal processing typically have to process large amounts of data. They often involve the handling of data arrays in the form of nested loops. Experiments show that for this kind of applications data transfer (memory access) operations consume much more power than data-path operations. Our objective is to reduce memory access related power consumption by reducing the number of data transfers between processor and memory, or between a higher (closer to processor) level of memory and a memory at a lower level using source program transformation. The procedure involves profiling, inlining and globed transformation. The effectiveness of this procedure is illustrated by applying it to the software for a wideband adaptive multi-rate (WB-AMR) speech decoder which can be obtained from the official website of the 3rd Generation Partnership Project (3GPP).