ACM Transactions on Design Automation of Electronic Systems最新文献

Design space exploration (DSE) is a key activity in embedded design processes, where a mapping between applications and platforms that meets the process design requirements must be found. Finding such mappings is very challenging due to the complexity of modern embedded platforms and applications. DSE tools aid in this challenge by potentially covering sections of the design space that could be unintuitive to designers, leading to more optimised designs. Despite this potential benefit, DSE tools remain relatively niche in the embedded industry. A significant obstacle hindering their wider adoption is integrating such tools into embedded design processes.

We present two contributions that address this integration issue. First, we present the design space identification (DSI) approach for systematically constructing DSE solutions that are modular and tuneable. Modularity means that DSE solutions can be reused to construct other DSE solutions, while tuneability means that the most specific DSE solution is chosen for the target DSE problem. Moreover, DSI enables transparent cooperation between exploration algorithms. Second, we present IDeSyDe, an extensible DSE framework for DSE solutions based on DSI. IDeSyDe allows extensions to be developed in different programming languages in a manner compliant with the DSI approach.

We showcase the relevance of these contributions through five different case studies. The case study evaluations showed that non-exploration DSI procedures create overheads, which are marginal compared to the exploration algorithms. Empirically, most evaluations average 2% of the total DSE request. More importantly, the case studies have shown that IDeSyDe indeed provides a modular and incremental framework for constructing DSE solutions. In particular, the last case study required minimal extensions over the previous case studies so that support for a new application type was added to IDeSyDe.

In this study, we explore the capability of Large Language Models (LLMs) to automate hardware design by automatically completing partial Verilog code, a common language for designing and modeling digital systems. We fine-tune pre-existing LLMs on Verilog datasets compiled from GitHub and Verilog textbooks. We evaluate the functional correctness of the generated Verilog code using a specially designed test suite, featuring a custom problem set and testing benches. Here, our fine-tuned open-source CodeGen-16B model outperforms the commercial state-of-the-art GPT-3.5-turbo model with a 1.1% overall increase. Upon testing with a more diverse and complex problem set, we find that the fine-tuned model shows competitive performance against state-of-the-art gpt-3.5-turbo, excelling in certain scenarios. Notably, it demonstrates a 41% improvement in generating syntactically correct Verilog code across various problem categories compared to its pre-trained counterpart, highlighting the potential of smaller, in-house LLMs in hardware design automation.

We release our training/evaluation scripts and LLM checkpoints as open-source contributions.

Abstract. Field-Programmable Gate Arrays (FPGAs) employ a large number of SRAM cells to provide a flexible routing architecture which have a significant impact on the FPGA’s area and power consumption. This flexible routing allows for a rather easy realization of the desired functionality, but our evaluations show that the full routing flexibility is not required in many occasions. In this work, we focus on what is actually needed and introduce a new switch-box realization what we call Turn-Restricted Switch-Boxes which supports only a subset of possible turns. The proposed method increases the utilization rate of FPGA switch-boxes by eliminating the unemployed resources. Experimental evaluations confirm that the area and average power consumption can be reduced by 12.8% and 14.1%, on average, respectively and the FPGA routing susceptibility to SEU and MBU can be improved by 18.2%, on average, by imposing negligible performance.

Logic built-in self-test (LBIST) approaches use an on-chip logic block for test generation and thus enable in-field testing. Recent reports of silent data corruption underline the importance of in-field testing. In a class of storage-based LBIST approaches, compressed tests are stored on-chip and decompressed by an on-chip decompression logic. The on-chip storage requirements may become a bottleneck when the number of compressed tests is large. In this case, using each compressed test for applying several different tests allows the storage requirements to be reduced. However, producing different tests from each compressed test has a hardware overhead. This article suggests a new on-chip storage scheme for compressed tests that eliminates the additional hardware overhead. Under the new storage scheme, a set of N B-bit compressed tests targeting a set of faults F₀ is translated into a sequence S of N · B bits. Every B consecutive bits of S are considered as a compressed test. The sequence S thus yields close to N · B compressed tests, magnifying the test data stored in S almost B times. Taking advantage of the extra tests, the article describes a software procedure that is applied off-line to reduce S without losing fault coverage of F₀. Experimental results for benchmark circuits demonstrate significant reductions in the storage requirements of S, and significant increases in the fault coverage of a second set of faults, F₁.

Bayesian optimization (BO) is an efficient global optimization method for expensive black-box functions. Whereas, the expansion for high-dimensional problems and large sample budgets still remains a severe challenge. In order to extend BO for large-scale analog circuit synthesis, a novel computationally efficient parallel BO method, D³PBO, is proposed for high-dimensional problems in this work. We introduce the dynamic domain decomposition method based on maximum variance between clusters. The search space is decomposed into subdomains progressively to limit the maximal number of observations in each domain. The promising domain is explored by multi-trust region based batch BO with the local Gaussian process (GP) model. As the domain decomposition progresses, the basin-shaped domain is identified using a GP-assisted quadratic regression method and exploited by the local search method BOBYQA to achieve faster convergence rate. The time complexity of D³PBO is constant for each iteration. Experiments demonstrate that D³PBO obtains better results with significant less runtime consumption compared to state-of-the-art methods. For the circuit optimization experiments, D³PBO achieves up to 10 × runtime speedup compared to TuRBO with better solutions.

Typical embedded processors, such as Digital Signal Processors (DSPs), usually adopt Very Long Instruction Word (VLIW) architecture to improve computing efficiency. The performance of VLIW processors heavily relies on Instruction-Level Parallelism (ILP). Therefore, it is crucial to develop an efficient instruction scheduling algorithm to explore more ILP. While heuristic algorithms are widely used in modern compilers due to simple implementation and low computational cost, they have limitations in providing accurate solutions and are prone to local optima. On the other hand, exact algorithms can usually find the optimal solution, but their high time overhead makes them less suitable for large-scale problems. This paper proposes a two-dimensional constrained dynamic programming (TDCDP) approach and a quantitative model for instruction scheduling. The TDCDP approach achieves near-optimal solutions within an acceptable time overhead. Furthermore, we integrate our TDCDP approach into mainstream compiler architecture, encompassing Pre- and Post-RA (register allocation) scheduling. We conduct a quantitative evaluation of TDCDP compared to four heuristic algorithms on a typical VLIW processor. Our approach achieves an efficiency improvement of up to 58.34% in final solutions compared to the heuristic algorithms. Additionally, the Post-RA Scheduling enhances programs with an average speedup of 14.04% than solely applying the Pre-RA Scheduling.

Artificial neural networks (ANNs) and spiking neural networks (SNNs) are two general approaches to achieve artificial intelligence (AI). The former have been widely used in academia and industry fields. The latter, SNNs, are more similar to biological neural networks and can realize ultra-low power consumption, thus have received widespread research attention. However, due to their fundamental differences in computation formula and information coding, the two methods often require different and incompatible platforms. Alongside the development of AI, a general platform that can support both ANNs and SNNs is necessary. Moreover, there are some similarities between ANNs and SNNs, which leaves room to deploy different networks on the same architecture. However, there is little related research on this topic. Accordingly, this paper presents an energy-efficient, scalable, and non-Von Neumann architecture (EPHA) for ANNs and SNNs. Our study combines device-, circuit-, architecture-, and algorithm-level innovations to achieve a parallel architecture with ultra-low power consumption. We use the compensated ferrimagnet to act as both synapses and neurons to store weights and perform dot-product operations, respectively. Moreover, we propose a novel computing flow to reduce the operations across multiple crossbar arrays, which enables our design to conduct large and complex tasks. On a suite of ANN and SNN workloads, the EPHA is 1.6 × more power efficient than a state-of-the-art design, NEBULA, in the ANN mode. In the SNN mode, our design is 4 orders of magnitude more than the Loihi in power efficiency.

Analog circuit optimization and design presents a unique set of challenges in the IC design process. Many applications require for the designer to optimize for multiple competing objectives which poses a crucial challenge. Motivated by these practical aspects, we propose a novel method to tackle multi-objective optimization for analog circuit design in continuous action spaces. In particular, we propose to: (i) Extrapolate current techniques in Multi-Objective Reinforcement Learning (MORL) to continuous state and action spaces. (ii) Provide for a dynamically tunable trained model to query user defined preferences in multi-objective optimization in the analog circuit design context.

In this paper, we introduce two novel methods to detect adversarial examples utilizing pixel value diversity. First, we propose the concept of pixel value diversity (which reflects the spread of pixel values in an image) and two independent metrics (UPVR and RPVR) to assess the pixel value diversity separately. Then we propose two methods to detect adversarial examples based on the threshold method and Bayesian method respectively. Experimental results show that compared to an excellent prior method LID, our proposed methods achieve better performances in detecting adversarial examples. We also show the robustness of our proposed work against an adaptive attack method.

Logic camouflage is a widely adopted technique that mitigates the threat of intellectual property (IP) piracy and overproduction in the integrated circuit (IC) supply chain. Camouflaged logic achieves functional obfuscation through physical-level ambiguity and post-manufacturing programmability. However, discussions on programmability are confined to the level of logic cells/gates, limiting the broader-scale application of logic camouflage. In this work, we propose a novel module-level configuration methodology for programmable camouflaged logic that can be implemented without additional hardware ports and with negligible resources. We prove theoretically that the configuration of the programmable camouflaged logic cells can be achieved through the inputs and netlist of the original module. Further, we propose a novel lightweight ferroelectric FET (FeFET)-based reconfigurable logic gate (rGate) family and apply it to the proposed methodology. With the flexible replacement and the proposed configuration-aware conversion algorithm, this work is characterized by the input-only programming scheme as well as the combination of high output error rate and point-function-like defense. Evaluations show an average of >95% of the alternative rGate location for camouflage, which is sufficient for the security-aware design. We illustrate the exponential complexity in function state traversal and the enhanced defense capability of locked blackbox against SAT attacks compared to key-based methods. We also preserve an evident output Hamming distance and introduce negligible hardware overheads in both gate-level and module-level evaluations under typical benchmarks.