Bit-level compiler optimization for ultra low-power embedded systems
Seonyeong Heo, Jiho Kim, Woohyeop Im, Ji‐Yun Moon, Daehee Jang · Journal of Systems Architecture · 2025
Achieving ultra low-power consumption is essential for embedded systems deployed in harsh environments, such as space and deep sea locations, where energy resources are scarce and physical accessibility is limited. Typically, these systems employ ultra low-power microcontrollers that operate on narrow data widths of 8 or 16 bits at the microarchitecture level. If software developers do not carefully consider the data widths during programming, the resulting programs may be suboptimally optimized for these ultra low-power systems. To address this issue and enable more efficient low-power computing, this work proposes a novel optimizing compiler that supports bit-level analyses and transformations. The proposed compiler analyzes how each individual bit of a data item is utilized within a program to determine its optimal width. Consequently, the proposed compiler reduces unnecessary data movements and computational overhead on ultra low-power processors. This work implements the prototype compiler on top of the LLVM compiler framework and evaluates the performance impact of the optimized embedded applications with a processor simulator.