As conventional CPU-based security architectures struggle to scale with ever-growing network bandwidths and increasingly sophisticated cyberattacks,the data processing unit(DPU),a specialized processor for datacenter infrastructure,has emerged as a transformative foundation for secure and high-performance com-puting.Unlike prior fragmented studies,this work proposes a comprehensive security framework for DPUs by systematically investigating the DPUs'dual role in cybersecurity,serving both as an active security enforcer and as a critical component that must itself be protected.First,the framework offloads security policies onto the DPU to enable line-rate packet inspection and hardware-accelerated security processing.Second,the framework re-architects the DPU itself to defend against physical and architectural attacks,acknowledging that the DPU al-so introduces a new attack surface.We validate these two design directions through two representative case stud-ies,demonstrating the effectiveness and practicality of the proposed DPU security framework.Experimental re-sults show that the proposed framework reduces remote direct memory access(RDMA)cache side-channel detec-tion latency by up to 98.7%compared with the state-of-the-art,while enabling a trusted execution environment on field-programmable gate array(FPGA)-based DPUs with sub-100 ns overhead and less than 4%FPGA re-source consumption.
The decomposition-based chiplet design paradigm, which breaks monolithic system-on-chips (SoCs) into smaller chiplets, has proved effective in reducing costs and accelerating development. The vast design space of multichiplet systems necessitates automated techniques to maximize their benefits while minimizing overheads. However, current chiplet decomposition flows lack support for exploring reusable chiplets, missing opportunities to efficiently amortize nonrecurring engineering (NRE) costs. To fully unleash the economic potential of chiplets, we propose Chipletizer 2.0, a cost-driven framework that guides SoC decomposition and enables chiplet reuse across a line of products. This early-stage chiplet planning framework determines critical system parameters involving the partition, floorplan, and die-to-die (D2D) interface, based on user-specified optimization goals. Experimental results demonstrate that, compared with the existing chiplet decomposition techniques, our proposed framework achieves significant cost improvements on realistic product lines with acceptable overheads.
Fully homomorphic encryption (FHE) enables computation on encrypted data, but its long ciphertext dataflow and high-dimensional modular arithmetic make it vulnerable to silent data corruption caused by transient hardware faults. Existing protection methods either target dedicated accelerators or impose substantial execution, modular-arithmetic, and memory-access overheads on CPUs. This work presents an efficient fault-tolerance scheme for CPU-based CKKS computation. It checks the input-output consistency of polynomial operators while reducing protection overhead at three levels. First, modulus-aware bucket checksum exploits wide CPU accumulators to reduce expensive modular reductions. Second, dataflow-fused in-operator checking embeds checksum accumulation into operator dataflows, avoiding separate scans of long ciphertext polynomials. Third, cross-operator check fusion eliminates redundant checksum computations between adjacent operators while preserving end-to-end checking invariants. We implement the scheme in OpenFHE and evaluate it on representative encrypted applications and ciphertext primitives under random single-bit transient faults. It achieves a 100 percent empirical detection rate across 150,000 non-crashing corrupted-result cases and maintains application accuracy close to the fault-free baseline over a wide range of fault rates. The scheme incurs only 6.0 percent to 8.4 percent runtime overhead, averaging 6.8 percent, and reduces average protection overhead by 4.9 times compared with direct checksum-based protection.
Fully Homomorphic Encryption (FHE) imposes substantial memory bandwidth demands, presenting significant challenges for efficient hardware acceleration. Near-memory Processing (NMP) has emerged as a promising architectural solution to alleviate the memory bottleneck. However, the irregular memory access patterns and flexible dataflows inherent to FHE limit the effectiveness of existing NMP accelerators, which fail to fully utilize the available near-memory bandwidth. In this work, we propose FlexMem, a near-memory accelerator featuring high-parallel computational units with varying memory access strides and interconnect topologies to effectively handle irregular memory access patterns. Furthermore, we design polynomial and ciphertext-level dataflows to efficiently utilize near-memory bandwidth under varying degrees of polynomial parallelism and enhance parallel performance. Experimental results demonstrate that FlexMem achieves 1.12 times of performance improvement over state-of-the-art near-memory architectures, with 95.7 utilization.
Transformer-based models dominate modern AI workloads but exacerbate memory bottlenecks due to their quadratic attention complexity and ever-growing model sizes. Existing accelerators, such as Groq and Cerebras, mitigate off-chip traffic with large on-chip caches, while algorithmic innovations such as FlashAttention fuse operators to avoid materializing large attention matrices. However, as off-chip traffic decreases, our measurements show that on-chip SRAM accesses account for over 60
The Trusted Execution Environment (TEE) has been widely implemented by modern hardware vendors to protect security and privacy-sensitive applications and data, such as Intel SGX/TDX, ARM TrustZone, AMD SEV, and RISC-V Penglai. However, existing TEE systems face challenges in balancing memory isolation among security, performance, and scalability requirements. Segment-based memory isolation mechanisms, like RISC-V PMP, struggle to scale effectively to the large number of segments needed for confidential cloud and data center environments. On the other hand, table-based isolation methods, such as page tables, combine address translation with memory protection, leading to inefficient cross-enclave communication and potential security vulnerabilities like Rowhammer attacks.This article introduces a novel TEE system, LayerTEE, which decouples memory protection (to segments) from address translation (to page tables). This design improves communication performance by dynamically adjusting memory protection capabilities, without sacrificing application compatibility. LayerTEE enhances enclave security and scalability by designing a multilayer segment-based isolation mechanism. We have built a prototype of LayerTEE based on FPGA, incorporating hardware extensions and software support. The evaluation demonstrates that LayerTEE significantly surpasses existing TEE solutions, achieving three orders of magnitude lower communication latency and 10x greater scalability while maintaining robust security guarantees.
Fully Homomorphic Encryption (FHE) introduces a novel paradigm in privacy-preserving computation, but operating on encrypted data imposes significant challenges, elevating data transmission, memory access demands, and programming complexity. Consequently, developing an efficient and usable system becomes vital. Conventional FHE accelerators often prioritize computational performance, typically assuming abundant encrypted data resides in accelerator memory. However, this perspective frequently overlooks the inefficiencies of the PCIe bus and main memory, alongside the complexities of optimizing for dedicated hardware in real-world deployments. This paper proposes Hypnos, a hardware/software co-design framework for memory-efficient homomorphic processing. The Hypnos framework pairs a novel processing unit architecture with a dedicated Hypnos Compiler. In architecture, the heterogeneous processing unit based on homomorphic encryption paging memory management system to reduce memory fragmentation and optimize the PCIe traffic. In software, the Hypnos compiler which is able to automatically translate high-level FHE schemes into optimized hardware commands. It schedules the data placement in cooperation with our memory management system to effectively harness the performance of hardware. This co-design of hardware and compiler not only reduces memory access and execution time but also lowers the complexity of deploying FHE applications. Finally, We implement Hypnos on the QianKun FPGA Card and highlight the following results: (1) outperforms SOTA ASIC and FPGA solutions in data-intensive applications by up to 2.75× and 4.72×; (2) the communication overhead is reduced by 4.85× compared to traditional architectures; (3) up to 30.1× and 20.7× energy efficiency improvement compared to ASIC-based ARK and FPGA-based Poseidon for ResNet-20 respectively.
fully homomorphic encryption (FHE) is a promising privacy-preserving technique that has drawn increasing attention from academia and industry. It allows computation directly on encrypted data without decryption. However, FHE incurs intensive computations. Chiplet-based designs integrate multiple processors, delivering high performance and thereby are embraced by computation-intensive FHE tasks. Despite the chiplet-based system with various processors, it is designed for unencrypted applications, falling short in handling FHE with unique ciphertext manipulations. One common approach to make it capable of FHE is developing a new FHE accelerator. However, this approach overlooks existing abundant resources already in the system and introduces a large area overhead. In this article, we propose Chiplever, a framework that empowers a non-FHE-tailored system to efficiently support FHE tasks via a hardware extension. Chiplever aims to leverage the existing resources already in the room for FHE tasks. To achieve this, 1) Chiplever introduces a hardware extension with an FHE unit providing efficient function support for FHE operators. 2) Chiplever proposes an FHE coordinator in the extension, which enables direct ciphertext transfer between the newly introduced extension and existing chiplets, achieving efficient integration of the extension. 3) Chiplever lowers the high-level homomorphic operations to primitive operators that can be matched by existing chiplets and constructs a fine-grained computation graph (CG). Based on this, Chiplever employs a task scheduling algorithm, which partitions the FHE task across the extension and existing chiplets to exploit the parallelism between them and reduce the ciphertext communication overheads. With these hardware and software optimizations, Chiplever achieves efficient FHE acceleration. Compared with prior FHE ASICs, Chiplever achieves $9.6{\times }$ - $15.9{\times }$ speedup and $6.2{\times }$ - $67.4{\times }$ throughput improvement on TFHE, while consuming only 18.8%-35.6% of the area overhead of dedicated FHE ASICs.
Despite limited success in large language model (LLM)-based register-transfer-level (RTL) code generation, the root causes of errors remain poorly understood. To address this, we conduct a comprehensive error analysis, finding that most failures arise not from deficient reasoning, but from a lack of RTL programming knowledge, insufficient circuit understanding, ambiguous specifications, or misinterpreted multimodal inputs. Leveraging in-context learning, we propose targeted correction techniques: a retrieval-augmented generation (RAG) knowledge base to supply domain expertise; design description rules with rule-checking to clarify inputs; external tools to convert multimodal data into LLM-compatible formats; and an iterative simulation-debugging loop for remaining errors. Integrating these into an LLM-based framework yields significant improvement, achieving 98.1
In automatic test pattern generation (ATPG), SAT-based methods are typically used to complement structural approaches, especially for addressing hard-to-detect faults. However, as the size and complexity of circuits grow, SAT-based ATPG faces challenges like pattern inflation and excessive runtime, limiting its overall performance. The key problem lies in the fact that current mainstream SAT solvers perform complete assignments for all primary inputs of the fault’s transitive fanin cone without considering the detection of other faults, making test compaction extremely difficult and time consuming. In this paper, a novel SAT solver PA-MiniSat is proposed, which is capable of generating partial assignments for solving variables and significantly reduces the number of specified bits in test cubes. As an extension of MiniSat, it employs a full-literal watching technique and a circuit-adapted heuristic branching strategy, achieving overall improved performance in ATPG. Based on PA-MiniSat, a hybrid ATPG framework PastATPG is proposed for better test compaction, which tightly integrates structural algorithms with the SAT solver into the unified test compaction flow. Experimental results demonstrate that our method outperforms other SAT solvers in pattern compaction and, in some cases, even surpasses commercial ATPG tools in terms of speed. The code is available at https://github.com/sklp-eda-lab/PastATPG.
As integrated circuits grow in complexity, test point insertion (TPI) has become vital for enhancing testability and improving reliability in design for test (DFT). Recent studies have shown the effectiveness of deep learning-based TPI using graph neural networks (GNNs) in improving test quality. However, the high cost of collecting training data, incomplete capture of the intrinsic characteristics of circuits, and the vast search space in large circuits hinder the performance of existing intelligent approaches. This paper introduces HighTPI, a two-stage learning approach for TPI to effectively reduce the number of test patterns, which leverages hierarchical graph representation by constructing a hypergraph based on hypernodes in fanout-free regions (FFRs). HighTPI better captures multi-fanout reconvergence information while lowering the cost of obtaining ground-truth labels due to the smaller scale of the FFR-based hypergraph. Two specialized GNNs are designed in stage I to select candidate insertion points for observation and control points, respectively. This integration of expert knowledge through supervised learning helps guide the reinforcement learning process in stage II, mitigating the challenges of sparse rewards and a large decision space. The experimental results demonstrate that HighTPI outperforms other TPI methods in terms of the trade-off between pattern reduction and fault coverage enhancement.
One-shot post-training pruning enhances the deployment of billion-scale large language models (LLMs), with the pruning metric playing a pivotal role in determining which weights to remove. However, existing metrics underperform due to their reliance on a simple symbolic combination of weights and activations, overlooking imbalanced weight magnitudes and the disproportionate influence of activation outliers.To overcome these limitations, we introduce \textbf{BaWA}, a novel pruning metric that systematically \underline{Ba}lances \underline{W}eight and \underline{A}ctivation distributions for more effective pruning.BaWA introduces two key innovations: \textbf{magnitude normalization}, which mitigates weight imbalance across channels for fairer pruning decisions, and \textbf{outlier regularization}, which reduces the impact of activation outliers, ensuring more appropriate channel prioritization. To further enhance its effectiveness, BaWA incorporates an efficient and automatic framework for optimizing normalization and regularization hyperparameters. Extensive experiments validate BaWA as a state-of-the-art (SOTA) pruning metric. For instance, applying BaWA to induce 2:4 sparsity in Mistral-7B reduces perplexity in language comprehension by 2.49 and improves average downstream task accuracy by 3.08\%, outperforming the previous SOTA method Wanda.
The billion-scale Large Language Models (LLMs) necessitate deployment on expensive server-grade GPUs with large-storage HBMs and abundant computation capability. As LLM-assisted services become popular, achieving cost-effective LLM inference on budget-friendly hardware becomes the current trend. This has sparked extensive research into relocating LLM parameters from expensive GPUs to external host memory. However, the restricted bandwidth between the host and GPU memory limits the inference performance of existing solutions. This work introduces Hermes, a budget-friendly system that leverages the near-data processing units (NDP) within commodity DRAM DIMMs to enhance the performance of a single consumer-grade GPU, achieving efficient LLM inference. We recognize that the inherent activation sparsity in LLMs naturally divides weight parameters into two categories, termed "hot" and "cold" neurons, respectively. Hot neurons, which consist of only approximately 20% of all weight parameters, account for 80% of the total computational load. In contrast, cold neurons make up the other 80% of parameters but are responsible for just 20% of the computational workload. Leveraging this observation, we propose a heterogeneous computing strategy: mapping hot neurons to a single computation-efficient GPU without large-capacity HBMs, while offloading cold neurons to NDP-DIMMs, which offer large memory size but limited computation capabilities. In addition, the dynamic nature of activation sparsity necessitates a real-time partition of hot and cold neurons and adaptive remapping of cold neurons across multiple NDP-DIMM modules. To tackle these issues, we introduce a lightweight predictor that ensures optimal real-time neuron partition and adjustment between GPU and NDP-DIMMs. Furthermore, we utilize a window-based online scheduling mechanism to maintain load balance among multiple NDP-DIMM modules. In summary, Hermes facilitates the deployment of LLaMA2-70B on consumer-grade hardware at a rate of 13.75 tokens/s and realizes an average 75.24x speedup over the state-of-the-art offloading-based inference system on popular LLMs.
Quantization is a widely-used compression technology to reduce the overhead of serving large language models (LLMs) on terminal devices and in cloud data centers. However, prevalent quantization methods, such as 8-bit weight-activation or 4-bit weight-only quantization, achieve limited performance improvements due to poor support for low-precision (e.g., 4-bit) activation. This work, for the first time, realizes practical W4A4KV4 serving for LLMs, fully utilizing the INT4 tensor cores on modern GPUs and reducing the memory bottleneck caused by the KV cache. Specifically, we propose a novel fine-grained mixed-precision quantization algorithm (FMPQ) that compresses most activations into 4-bit with negligible accuracy loss. To support mixed-precision matrix multiplication for W4A4 and W4A8, we develop a highly optimized W4Ax kernel. Our approach introduces a novel mixed-precision data layout to facilitate access and fast dequantization for activation and weight tensors, utilizing the GPU's software pipeline to hide the overhead of data loading and conversion. Additionally, we propose fine-grained streaming multiprocessor (SM) scheduling to achieve load balance across different SMs. We integrate the optimized W4Ax kernel into our inference framework, COMET, and provide efficient management to support popular LLMs such as LLaMA-3-70B. Extensive evaluations demonstrate that, when running LLaMA family models on a single A100-80G-SMX4, COMET achieves a kernel-level speedup of \textbf{$2.88\times$} over cuBLAS and a \textbf{$2.02 \times$} throughput improvement compared to TensorRT-LLM from an end-to-end framework perspective.
Graph Neural Networks (GNNs) are increasingly applied across various domains, including social media and recommendation systems. However, data privacy protection has become a critical issue for GNN applications. Fully Homomorphic Encryption (FHE), which enables computation on encrypted data, has emerged as a mainstream solution for secure GNN inference. However, due to the high computational costs of FHE-based GNNs, dedicated accelerators are necessary to make them practical. Existing CKKS-based GNN algorithms require large encryption parameters, imposing high demands on hardware resources. The state-of-the-art design PPGNN is hardware friendly on memory by combining CKKS with TFHE, but TFHE’s SISD computing characteristic causes a dramatic increase in computational overhead, limiting its performance benefits. This paper proposes a novel software-hardware code-signed GNN accelerator architecture, Uranus, which integrates a hardware-friendly algorithmic framework with a matching accelerator design. The inference framework leverages CKKS and BFV schemes to enable efficient linear layer computations and SIMD-based nonlinear calculations with reduced encryption parameters suitable for hardware constraints. Additionally, the highly reconfigurable hardware accelerator maximizes utilization and performance. Key results demonstrate the following: (1) up to 92× speedup compared to CKKS accelerators; (2) achieves 3.3× to 4.2× performance improvement over the SOTA PPGNN architecture; (3) over 119× in energy efficiency improvement compared to PPGNN.
Domain-specific architecture has greatly improved performance and energy efficiency in in-memory databases, especially for accelerating single-functional computing logic in analytic query processing, such as sort, join and aggregation. However, as data volumes surge exponentially, these dedicated accelerators are struggling to satisfy the burgeoning demand for handling intricate and multifaceted workloads. A major challenge lies in establishing a flexible framework that engages these 'coarse-grained' units without incurring extra overheads from hardware integration, programming, compilation, runtime and operating systems. In this paper, the kernel processing unit (KPU) is proposed to optimize CPU-accelerator heterogeneous systems for in-memory databases. KPU provides a unified interface to consolidate all database query operators. In terms of KPU hardware architecture, kernel customization and data transmission are two critical bottlenecks. To address the challenges, multiple independently designed homogeneous table cores are integrated to support flexible high-performance SQL queries, and a customized efficient data management system (DMS) works collaboratively to maximize the utilization of on-chip memory bandwidth. Additionally, a database application-specific KPU instruction set architecture (KISA) dedicated to parallel analytical query processing is proposed to enable parallel KPU programming. To trade off between accelerator computing capacity and data transfer latency, KPU designs an offloading mechanism to map SQL queries between the CPU and accelerator adaptively based on a performance model and a function simulator. The experiments demonstrate that KPU surpasses the general-purpose CPU and GPU by an average of 24.5x and 8.75x, respectively.
High-resolution (HR) videos have gained popularity with the widespread adoption of high-definition displays. Super-resolution (SR) techniques aim to recover HR frames from low-resolution (LR) frames. While deep neural network (DNN)-based SR methods have outperformed traditional techniques in quality, they face performance challenges. FPGA-based SR accelerators have been developed to optimize the performance and power efficiency. However, most of these accelerators process only uncompressed video frames and perform per-frame DNN inference, overlooking the temporal-spatial information inherent in compressed video bitstreams. We propose a novel compressed video SR workflow that includes a codec information reuse algorithm and a dedicated FPGA accelerator named Co-ViSu. Our approach leverages the observation that non-key frames can be reconstructed using codec information and HR key-frames, significantly reducing DNN computations. The Co-ViSu algorithm employs subpixel interpolation to enhance high-frequency details and an MV-aware method to improve SR reconstruction quality. The Co-ViSu hardware integrates decoder, SR, and encoder engines within a parallel pipeline architecture, utilizing codec information reuse to bypass non-key frame decoding, eliminate complex DNN computations, and accelerate encoding processes. Experimental results demonstrate that Co-ViSu achieves performance improvements ranging from 3.6x to 9.4x and a 4.2x gain in energy efficiency with minimal quality loss compared to traditional flow. Additionally, Co-ViSu offers a 2.1x increase in throughput compared to state-of-the-art solutions.
Deep learning has significantly advanced Electronic Design Automation (EDA), with circuit representation learning emerging as a key area for modeling the relationship between a circuit's structure and functionality. Existing methods primarily use either Large Language Models (LLMs) for Register Transfer Level (RTL) code analysis or Graph Neural Networks (GNNs) for netlist modeling. While LLMs excel at high-level functional understanding, they struggle with detailed netlist behavior. GNNs, however, face challenges when scaling to larger sequential circuits due to long-range information dependencies and insufficient functional supervision, leading to decreased accuracy and limited generalization. To address these challenges, we propose MOSS, a multimodal framework that integrates GNNs with LLMs for sequential circuit modeling. By enhancing D-type Flip-Flop (DFF) node features with embeddings from fine-tuned LLMs on RTL code, we focus the GNN on critical anchor points, reducing reliance on long-range dependencies. The LLM also provides global circuit embeddings, offering efficient supervision for functionality-related tasks. Additionally, MOSS introduces an adaptive aggregation method and a two-phase propagation mechanism in the GNN to better model signal propagation and sequential feedback within the circuit. Experimental results demonstrate that MOSS significantly improves the accuracy of functionality and performance predictions for sequential circuits compared to existing methods, particularly in larger circuits where previous models struggle. Specifically, MOSS achieves a 95.2% accuracy in arrival time prediction.
Field Programmable Gate Arrays (FPGAs) are widely used to implement the network interface controller (NIC). To measure the network traffic moving through the NIC, sketching algorithms have emerged as an accurate and storage-efficient solution. However, current FPGA-based sketch designs fail to support diverse measurement tasks sustainably. We propose FUS based on UnivMon, a multi-level universal sketch with solid theoretical guarantees for diverse measurement tasks. FUS consists of pessimistic UnivMon architecture (PUMA) and optimistic UnivMon architecture (OUMA). PUMA utilizes a homogeneous block RAM (BRAM) design, which is easy to implement but has high BRAM use. Alternatively, OUMA utilizes a heterogeneous memory design that reduces BRAM use but encounters long and uncertain off-chip memory-access latency. We use outstanding transactions to hide the long latency. Direct data forwarding and snooping are proposed to resolve the data dependencies between outstanding transactions. Write coalescing is proposed to reduce the off-chip memory-write transactions. PUMA and OUMA can sustain the maximum packet rate under 100 Gbps. Given the same BRAM budget, OUMA can achieve higher measurement quality than PUMA and the existing multi-sketch design.