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Mixed-cell-height circuits have become popular in advanced technologies for better power, area, routability, and performance tradeoffs. With technology and region constraints imposed by modern circuit designs, the mixed-cell-height legalization problem has become even more challenging. Additionally, an ideal legalization method should minimize both the average and maximum cell movements to preserve the quality of a given placement as much as possible. In this article, we present an effective and efficient mixed-cell-height legalization algorithm to consider technology and region constraints while minimizing the average and maximum cell movements. We first present a fence region handling technique to unify the fence regions and the default region. To obtain a desired cell assignment, we then propose a movement-aware cell reassignment method by iteratively reassigning cells in locally dense areas to their desired rows. After cell reassignment, a technology-aware legalization is presented to remove cell overlaps while satisfying the technology constraints. Finally, we propose a technology-aware refinement to further reduce the average and maximum cell movements without increasing the technology constraints violations. Compared with the champion of the 2017 CAD Contest at ICCAD and the state-of-the-art work, experimental results based on the 2017 CAD Contest at ICCAD benchmarks show that our algorithm achieves the best average and maximum cell movements and significantly fewer technology constraint violations, in a comparable runtime. The experimental results based on the modified 2015 ISPD Contest benchmarks also demonstrate the effectiveness of our algorithm in minimizing the average and maximum cell movements, compared with state-of-the-art mixed-cell-height legalizers. [ABSTRACT FROM AUTHOR]

App caching is important for mobile devices, which enables fast switching and state restoration of apps by caching all the pages in memory. Memory swapping can improve app caching capability by evicting pages to the secondary storage. However, enabling memory swapping could induce jitters in interactions, which significantly degrades the user experience. As a result, storage-based swapping is disabled by default in most mobile devices. This article proposes a novel swap framework, SEAL, a user experience-aware two-level swapping, which maximizes the benefits of memory swapping and minimizes the negative impact on user experience in interactions. Inspired by a study on the access characteristics of a set of popular apps on mobile devices, the framework adopts compressed memory as the first swap level (SL1) and secondary storage as the second swap level (SL2). To optimize user experience comprehensively, three schemes are proposed. First, a novel page identification scheme is proposed to guide the page placement between these two levels. Second, a hidden page loading (HPL) scheme is proposed to load pages from SL2 to SL1 for optimized user experience during app execution. Finally, an app-granularity swapping scheme is proposed to swap data in the unit of apps. Experiments on real devices show that app caching capability is improved by $2.43\times $ on average when enabling SEAL while minimizing the negative impact on user experience. [ABSTRACT FROM AUTHOR]

Timing analysis of real-time systems must consider cache-related pre-emption delay (CRPD) costs when pre-emptive scheduling is used. While most previous work on CRPD analysis only considers instruction caches, the CRPD incurred on data caches is actually more significant. The state-of-the-art CRPD analysis methods are based on useful cache block (UCB) calculation. Unfortunately, as shown in this article, directly extending the existing UCB calculation techniques from instruction caches to data caches will lead to both unsoundness and significant imprecision. To solve these problems, we develop a new UCB calculation technique for data caches, which redefines the analysis unit (to address the unsoundness in the existing method) and precisely captures the dynamic cache access behavior by taking the temporal scopes of memory blocks into consideration. The experimental results show that our new technique yields substantially tighter CRPD estimations comparing with the state-of-the-art. [ABSTRACT FROM AUTHOR]