Assessing the Reliability of Successive Approximate Computing Algorithms under Fault Injection

International audienceThis work presents two fault injection and dependability test methodologies exploring the fault tolerance of successive approximation algorithms. This type of approximate computing algorithm can present an inherent fault tolerance, converging to a final correct output even under faults affecting processed data. A set of algorithms was implemented as embedded software in the ARM Cortex A9 processor of Xilinx Zynq-7000 series board. Experiments consist of exposing the decapsulated processor to laser beams targeting the data cache memory and emulation fault injections at the register file. Results show that successive approximation is effective in protecting the output from faults injected at the data cache memory, but not from the ones injected at the register file. The experiments also show that most of the silent data corruption errors provoked by data cache fault injections are not significant and can be accepted as correct by merely tolerating a result variation of as little as 1%