Efficient Fault-Tolerant Addition by Operand Width Considerat

Addition is a central operation in microcontrollers and hence faults should be detected for safety reasons. We extend the principle of recomputing with shifted operands (RESO) by doing the re-computation concurrently to the computation in the case of small operands. Thus, we generate a solution cheaper than two adders and faster than simple repetition. To extend RESO, we consider the actual bit-widths of the operands. We validate our method with data from static code analysis of two application kernels.