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High quality AI solutions require joint optimization of AI algorithms and their hardware implementations. In this work, we are the first to propose a fully simultaneous, Efficient Differentiable DNN (deep neural network) architecture and implementation co-search (EDD) methodology. We formulate the co-search problem by fusing DNN search variables and hardware implementation variables into one solution space, and maximize both algorithm accuracy and hardware implementation quality. The formulation is differentiable with respect to the fused variables, so that gradient descent algorithm can be applied to greatly reduce the search time. The formulation is also applicable for various devices with different objectives. In the experiments, we demonstrate the effectiveness of our EDD methodology by searching for three representative DNNs, targeting low-latency GPU implementation and FPGA implementations with both recursive and pipelined architectures. Each model produced by EDD achieves similar accuracy as the best existing DNN models searched by neural architecture search (NAS) methods on ImageNet, but with superior performance obtained within 12 GPU-hour searches. Our DNN targeting GPU is 1.40x faster than the state-of-the-art solution reported in Proxyless [1], and our DNN targeting FPGA delivers 1.45x higher throughput than the state-of-the-art solution reported in DNNBuilder [2]. [ABSTRACT FROM AUTHOR]

To speedup Deep Neural Networks (DNN) accelerator design and enable effective implementation, we propose HybridDNN, a framework for building high-performance hybrid DNN accelerators and delivering FPGA-based hardware implementations. Novel techniques include a highly flexible and scalable architecture with a hybrid Spatial/Winograd convolution (CONV) Processing Engine (PE), a comprehensive design space exploration tool, and a complete design flow to fully support accelerator design and implementation. Experimental results show that the accelerators generated by HybridDNN can deliver 3375.7 and 83.3 GOPS on a high-end FPGA (VU9P) and an embedded FPGA (PYNQ-Z1), respectively, which achieve a 1.8x higher performance improvement compared to the state-of-art accelerator designs. This demonstrates that HybridDNN is flexible and scalable and can target both cloud and embedded hardware platforms with vastly different resource constraints. [ABSTRACT FROM AUTHOR]

We present A-QED (Accelerator-Quick Error Detection), a new approach for pre-silicon formal verification of stand-alone hardware accelerators. A-QED relies on bounded model checking -- however, it does not require extensive design- specific properties or a full formal design specification. While A-QED is effective for both RTL and high-level synthesis (HLS) design flows, it integrates seamlessly with HLS flows. Our A-QED results on several hardware accelerator designs demonstrate its practicality and effectiveness: 1. A-QED detected all bugs detected by conventional verification flow. 2. A-QED detected bugs that escaped conventional verification flow. 3. A-QED improved verification productivity dramatically, by 30X, in one of our case studies (1 person-day using A-QED vs. 30 person-days using conventional verification flow). 4. A-QED produced short counterexamples for easy debug (37X shorter on average vs. conventional verification flow). [ABSTRACT FROM AUTHOR]

Resilience to errors in the underlying hardware is a key design objective for a large class of computing systems, from embedded systems all the way to the cloud. Sources of hardware errors include radiation, circuit aging, variability induced by manufacturing and operating conditions, manufacturing test escapes, and early-life failures. Many publications have suggested that cross-layer resilience, where multiple error resilience techniques from different layers of the system stack cooperate to achieve cost-effective resilience, is essential for designing cost-effective resilient digital systems. This paper presents a comprehensive overview of cross-layer resilience by addressing fundamental cross-layer resilience questions, by summarizing insights derived from recent advances in cross-layer resilience research, and by discussing future cross-layer resilience challenges. [ABSTRACT FROM AUTHOR]

While embedded FPGAs are attractive platforms for DNN acceleration on edge-devices due to their low latency and high energy efficiency, the scarcity of resources of edge-scale FPGA devices also makes it challenging for DNN deployment. In this paper, we propose a simultaneous FPGA/DNN co-design methodology with both bottom-up and top-down approaches: a bottom-up hardware-oriented DNN model search for high accuracy, and a top-down FPGA accelerator design considering DNN-specific characteristics. We also build an automatic co-design flow, including an Auto-DNN engine to perform hardware-oriented DNN model search, as well as an Auto-HLS engine to generate synthesizable C code of the FPGA accelerator for explored DNNs. We demonstrate our co-design approach on an object detection task using PYNQ-Z1 FPGA. Results show that our proposed DNN model and accelerator outperform the state-of-the-art FPGA designs in all aspects including Intersection-over-Union (IoU) (6.2% higher), frames per second (FPS) (2.48x higher), power consumption (40% lower), and energy efficiency (2.5x higher). Compared to GPU-based solutions, our designs deliver similar accuracy but consume far less energy. [ABSTRACT FROM AUTHOR]

A desirable feature of a development tool for SoC design is that, given the important applications in the domain to be targeted by the SoC, a powerful hardware-software partitioning engine is available to determine which function(s) shall be mapped to hardware. However, to provide high-quality partitioning, this engine must be able to consider a rich design space of possible alternate hardware and software implementations for each program region candidate for hardware acceleration, in turn making the task of finding the optimal mapping very difficult given the number of design points to consider and the need for accurate modeling of latency, power and area. In this work we propose a novel framework to enable hardware acceleration of performance-critical parts of an application, by addressing the problem of hardware/software partitioning under power and area constraints to minimize the overall program latency. Our flow is based on the LLVM compiler, and focuses on building a scalable compile-time partitioning algorithm while considering large sets of alternative hardware and software implementations for a particular region. To this end we develop a hybrid approach based on mixing semi-random selection of hardware design points and an Integer Linear Programming formulation of the mapping decision, along with iterative refinements of the solution. Experimental results demonstrate the capability of our approach to consider complex designs and yet output near-optimal partitioning decision. Our package is named RIP (Randomized ILP-based Partitioning), and is open source to benefit the research community. [ABSTRACT FROM AUTHOR]

Emerging technologies such as the Internet of Things (IoT) heavily rely on hardware security for data and privacy protection. However, constantly increasing integration complexity requires automatic synthesis to maintain the pace of innovation. We introduce the first High-Level Synthesis (HLS) flow that produces a security enhanced hardware design to directly prevent Hardware Trojan Horse (HTH) injection by a malicious foundry. Through analysis of entropy loss and criticality decay, the presented algorithms implement highly efficient resource-targeted information dispersion to counter HTH insertion. The flow is evaluated on existing HLS benchmarks and a new IoT-specific benchmark and shows significant resource savings. [ABSTRACT FROM AUTHOR]

Verification of modern day electronic circuits has become the bottleneck for the timely delivery of complex SoC designs. We develop a novel cross-layer hardware/software co-simulation framework that can effectively debug and verify an SoC design. We combine high-level C/C++ software with cycle-accurate SystemC hardware, uniquely identify various types of bugs, and help the hardware designer localize them. Experimental results show that we are able to detect and aid in localization of logic bugs from both C/C++ specifications as well as the high-level synthesis engine itself. Our framework is fully automated, representing an important step forward targeting fast and effective SoC design verification. [ABSTRACT FROM AUTHOR]

The smart electric grid in the United States is one of the largest and most complex cyber-physical systems (CPS) in the world and contains considerable uncertainties. Probabilistic optimal power flow (OPF) analysis is required to accomplish the electrical and economic operational goals. In this paper, we propose a novel algorithm to accelerate the computation of probabilistic OPF for large-scale smart grids through network reduction (NR). Cumulant-based method and Gram-Charlier expansion theory are used to efficiently obtain the statistics of system states. We develop a more accurate linear mapping method to compute the unknown cumulants. Our method speeds up the computation by up to 4.57X and can improve around 30% accuracy when Hessian matrix is ill-conditioned compared to the previous approach. [ABSTRACT FROM AUTHOR]

Reconfigurable devices are often employed in heterogeneous systems due to their low power and parallel processing advantages. An important usability requirement is the support of a homogeneous programming interface. Nevertheless, homogeneous programming interfaces do not eliminate the need for code tweaking to enable efficient mapping of the computation across heterogeneous architectures. In this work we propose a code optimization framework which analyzes and restructures CUDA kernels that are optimized for GPU devices in order to facilitate synthesis of high-throughput custom accelerators on FPGAs. The proposed framework enables efficient performance porting without manual code tweaking or annotation by the user. A hierarchical region graph in tandem with code motions and graph coloring of array variables is employed to restructure the kernel for high throughput execution on FPGAs. [ABSTRACT FROM AUTHOR]

In this paper, we propose a maze-routing-based clock tree routing algorithm integrated with buffer insertion, buffer sizing and topology generation that is able to consider general buffer insertion locations in order to achieve robust slew control. Buffer insertion along routing paths had been mostly avoided previously due to the difficulty to maintain low skew under such aggressive buffer insertion. We develop accurate timing analysis engine for delay and slew estimation and a balanced routing scheme for better skew reduction during clock tree synthesis. As a result, we can perform aggressive buffer insertion with buffer sizing and maintain accurate delay information and low skew. Experiments show that our synthesis results not only honor the hard slew constraints but also maintain reasonable skew. [ABSTRACT FROM AUTHOR]

Glitches (i.e. spurious signal transitions) are major sources of dynamic power consumption in modern FPGAs. In this paper, we present an FPGA-targeted, glitch-aware, high-level binding algorithm for power and area reduction, accomplished via dynamic power estimation and multiplexer balancing. Our binding algorithm employs a glitch-aware dynamic power estimation technique derived from the FPGA technology mapper in [6]. High-level binding results are converted to VHDL, and synthesized with Altera's Quartus II software, targeting the Cyclone II FPGA architecture. Power characteristics are evaluated with the Altera Power- Play Power Analyzer. The binding results of our algorithm are compared to LOPASS, a state-of-the-art low-power high-level synthesis algorithm for FPGAs. Experimental results show that our algorithm, on average, reduces toggle rate by 22% and area by 9%, resulting in a decrease in dynamic power consumption of 19%. To the best of our knowledge this is the first high-level binding algorithm targeting FPGAs that considers glitch power. [ABSTRACT FROM AUTHOR]