Variation in performance and power across manufactured parts and their operating conditions is a well-known issue in advanced CMOS processes. This paper proposes a resilient HW/SW architecture for shared-L1 processor clusters to combat both static and dynamic variations. We first introduce the notion of procedurelevel vulnerability (PLV) to expose fast dynamic voltage variation and its effects to the software stack for use in runtime compensation. To assess PLV, we quantify the effect of full operating conditions on the dynamic voltage variation of a post-layout processor in 45nm TSMC technology. Based on our analysis, PLV shows a range of 18mV−63mV inter-corner variation among the maximum voltage droop of procedures. To exploit this variation we propose a low-cost procedure hopping technique within the processor clusters, utilizing compile time characterized metadata related to PLV. Our results show that procedure hopping avoids critical voltage droops during the execution of all procedures while incurring less than 1 % latency penalty.

Abstract—Driven by flexibility, performance and cost constraints of demanding modern applications, heterogeneous System-on-Chip (SoC) is the dominant design paradigm in the embedded system computing domain. SoC architecture and heterogeneity clearly provide a wider power/performance scaling, combining high performance and power efficient generalpurpose cores along with massively parallel many-core-based accelerators. Besides the complex hardware, generally these kinds of platforms host also an advanced software ecosystem, composed by an operating system, several communication protocol stacks, and various computational demanding user applications. The necessity to efficiently cope with the huge HW/SW design space provided by this scenario makes clearly full-system simulator one of the most important design tools. We present in this paper a new emulation framework, called VirtualSoC, targeting the full-system simulation of massively parallel heterogeneous SoCs. I.