{"title":"UniCNet: Unified Cycle-Accurate Simulation for Composable Chiplet Network With Modular Design-Integration Workflow","authors":"Peilin Wang;Mingyu Wang;Zhirong Ye;Tao Lu;Zhiyi Yu","doi":"10.1109/LCA.2026.3653809","DOIUrl":"https://doi.org/10.1109/LCA.2026.3653809","url":null,"abstract":"Composable chiplet-based architectures adopt a two-stage design flow: first chiplet design, then modular integration, while still presenting a shared-memory, single-OS system view. However, the heterogeneous and modular nature of the resulting network may introduce performance inefficiencies and functional correctness issues, calling for an advanced simulation tool. In this paper, we introduce UniCNet, a unified and cycle-accurate network simulator designed for composable chiplet-based architectures, which is open-sourced. To achieve both accurate modeling and unified simulation, UniCNet employs a <italic>design-integration</i> workflow that closely aligns with the composable chiplet design flow. It supports several key features oriented towards composable chiplet scenarios and introduces the first cycle-level chiplet protocol interface model. UniCNet further supports multi-threaded simulation, achieving up to 4× speedup with no cycle accuracy loss. We validate UniCNet against RTL models and demonstrate its utility via several case studies.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"37-40"},"PeriodicalIF":1.4,"publicationDate":"2026-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146082129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Xami: Expert-Aware Adaptive Compression for Mixture-of-Experts on Sparse Tensor Cores","authors":"Johnson Umeike;Bahar Asgari","doi":"10.1109/LCA.2026.3679449","DOIUrl":"https://doi.org/10.1109/LCA.2026.3679449","url":null,"abstract":"Mixture-of-Experts (MoE) models reduce active computation through sparse routing; yet their significant memory overhead due to retaining the full parameter footprint of all experts remains a deployment challenge. To address this, we present <monospace><italic>Xami</i><monospace>, an expert-aware adaptive compression framework that exploits routing heterogeneity to apply differentiated structured sparsity across experts. By profiling per-layer activation distributions, <monospace><italic>Xami</i><monospace> preserves frequently activated experts at higher fidelity while more aggressively compressing infrequent ones, all while remaining compatible with native 2:4 Sparse Tensor Core (<monospace><italic>SpTCs</i><monospace>) hardware execution. Across different MoE architectures, <monospace><italic>Xami</i><monospace> consistently improves model-level compression over uniform 2:4 sparsity with minimal accuracy loss and competitive inference throughput. Our results demonstrate that expert heterogeneity can be translated into practical memory savings, achieving up to 2.4× compression over dense compared to just 1.8× achieved by uniform 2:4, without modifying the underlying hardware execution model, providing a highly desirable path toward more efficient MoE inference.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"154-157"},"PeriodicalIF":1.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chihyo Ahn;Shinnung Jeong;Liam Paul Cooper;Ruobing Han;Huanzhi Pu;Nicholas Parnenzini;Jisheng Zhao;Blaise Tine;Hyesoon Kim
{"title":"FastTrackGPU: Static-Analysis–Guided Analytical Modeling for Softcore GPUs","authors":"Chihyo Ahn;Shinnung Jeong;Liam Paul Cooper;Ruobing Han;Huanzhi Pu;Nicholas Parnenzini;Jisheng Zhao;Blaise Tine;Hyesoon Kim","doi":"10.1109/LCA.2026.3677349","DOIUrl":"https://doi.org/10.1109/LCA.2026.3677349","url":null,"abstract":"SoftGPUs make FPGA platforms practical data-parallel accelerators by providing a GPU-like programming model on top of an open RTL-to-software stack. However, their high configurability creates a large configuration space, making it difficult to identify workload-optimal designs under FPGA resource constraints. We address this challenge by proposing the first analytical model for softGPUs and four decision policies that aggressively prune the design space. Implemented in our FastTrackGPU framework, our lightweight analytical model driven by static analysis enables orders-of-magnitude faster configuration selection than Bayesian optimization while boosting kernel throughput by 1.55× (geomean) over area-greedy baselines.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"162-165"},"PeriodicalIF":1.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Calibrating DRAMPower Model for HPC: A Runtime Perspective From Real-Time Measurements","authors":"Xinyu Shi;Dina Abdelbaky;Thomas Ilsche;Saeideh Alinezhad Chamazcoti;Timon Evenblij;Mohit Gupta;Francky Catthoor","doi":"10.1109/LCA.2025.3615711","DOIUrl":"https://doi.org/10.1109/LCA.2025.3615711","url":null,"abstract":"Main memory’s rising energy consumption has emerged as a critical challenge in modern computing architectures, particularly in large-scale systems, driven by frequent access patterns, growing data volumes, and insufficient power management strategies. Accurate modeling of DRAM power consumption is essential to address this challenge and optimize energy efficiency. However, existing modeling tools often rely on vendor-provided datasheet values that are obtained under worst-case or idealized conditions. As a result, they fail to capture important system-level factors such as temperature variations, chip aging, and workload-induced variability, which leads to significant discrepancies between estimated and actual power consumption observed in real deployments. In this work, we propose a runtime calibration methodology for the DRAMPower model using energy measurements collected from real-system experiments. By applying custom memory benchmarks on an HPC cluster and leveraging fine-grained power monitoring infrastructure, we refine key current parameters (IDD values) in the model. Our calibration reduces the average energy estimation error to less than 5%, substantially improving modeling accuracy and making DRAMPower a more reliable tool for power-aware system design and optimization on the target server platform.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"218-221"},"PeriodicalIF":1.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148236237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haeeun Jung;Jaeyong Lee;Sanggu Lee;Huiwon Yun;Dongsuk Jeon;Nam Sung Kim;Jihong Kim
{"title":"KiF: Accelerating Low-Batch LLM Inference Using In-Flash KV Cache","authors":"Haeeun Jung;Jaeyong Lee;Sanggu Lee;Huiwon Yun;Dongsuk Jeon;Nam Sung Kim;Jihong Kim","doi":"10.1109/LCA.2026.3689575","DOIUrl":"https://doi.org/10.1109/LCA.2026.3689575","url":null,"abstract":"Deploying LLMs on edge devices is constrained by the memory-intensive, dynamic KV cache. While offloading the KV cache to SSDs expands capacity, it introduces severe bandwidth bottlenecks. Existing in-flash processing (IFP) solutions, optimized for static weights, fail to address the write-intensive nature and access pattern mismatches inherent to the KV cache. We propose KiF, a novel IFP solution that manages KV cache within flash chips, via reliable pseudo-SLC based write management and specialized in-flash GEMV accelerator. KiF delivers up to 4.1× higher throughput than existing SSD offloading solutions.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"174-177"},"PeriodicalIF":1.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148003568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rules, Not Rankings: Interpretable AI for Processor Microarchitecture Design Analysis","authors":"Abdoulaye Gamatié;Lincen Yang;Paulo Pimenta","doi":"10.1109/LCA.2026.3692901","DOIUrl":"https://doi.org/10.1109/LCA.2026.3692901","url":null,"abstract":"Expert-driven microarchitecture analysis provides valuable insights but fails to scale to modern design spaces, while black-box AI offers scalability at the cost of interpretability. We present PTAH, a data-driven methodology that combines codified expert knowledge with an interpretable conditional-density model. PTAH derives human-readable rules that link processor mechanism configurations to the full IPC probability distribution. Clustering these rules yields design principles that highlight key interactions, trade-offs, and behavioral regimes. A case study on SPEC CPU workloads shows that PTAH uncovers design insights while preserving full interpretability.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"194-197"},"PeriodicalIF":2.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148478932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"BISC: Rethinking Instruction Set Abstractions at Block Granularity","authors":"An Zhong;Hanzhi Hu;Zirui Ma;Mengzhu Li;Haibin Wu;Fulin Zhang;Jinyi Deng;Ceyu Xu;Wenming Li;Yang Hu;Jian Weng","doi":"10.1109/LCA.2026.3690895","DOIUrl":"https://doi.org/10.1109/LCA.2026.3690895","url":null,"abstract":"Most widely deployed ISAs for general-purpose processors expose a centralized register file and instruction-granular control flow, forcing modern CPUs to rely on complex microarchitectural mechanisms to reconcile execution with architectural state. Even in simple in-order designs, these abstractions impose back-and-forth execution overheads, while more aggressive processors further amplify them through register renaming, speculation, and in-order retirement. This letter presents the Block-based Instruction Set Computer (BISC), which rethinks ISA abstractions at block granularity. BISC eliminates architectural destination registers by binding each instruction's result to its position within a block, enabling block-local execution driven by operand availability while preserving control-flow semantics across blocks. Control flow is resolved at block entry, amortizing fetch and control overhead across multiple operations and enabling efficient expression of conditional selection without additional control-flow edges. We evaluate BISC using a single-issue in-order core with comparable area to a RISC-V baseline. Despite executing more operations and incurring a larger code footprint, BISC achieves a 34% geometric mean speedup across benchmarks. These results demonstrate that ISA-level execution abstractions play a critical role in processor efficiency, independent of microarchitectural optimizations.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"222-225"},"PeriodicalIF":2.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148442169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hardware-Accelerated Parallel Wrong-Path Execution for Spectre Gadget Detection","authors":"Fangzheng Lin;Zeyu Gao;Yanru Lin;Yangyu Chen;Hiroshi Sasaki","doi":"10.1109/LCA.2026.3700174","DOIUrl":"https://doi.org/10.1109/LCA.2026.3700174","url":null,"abstract":"Spectre vulnerabilities pose new threats to computer system security, and detecting Spectre gadgets is an important step toward effective countermeasures. Detection requires exploring program behavior along branch-mispredicted execution paths (i.e., wrong paths), which existing dynamic scanners emulate in software—incurring high overhead and limiting parallel exploration. This paper proposes a hardware-assisted dynamic gadget detection architecture that offloads wrong-path executions to a pool of in-order shadow cores on a specialized asymmetric multicore platform, enabling multiple paths to be explored in parallel. The design also features shadow memory versioning to preserve the memory view at the branch point without full memory duplication. We prototype the proposed architecture on an Xilinx VU13P FPGA. Evaluation shows that the prototype achieves 1.25–5.24 × speedup over software-based detectors.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"239-242"},"PeriodicalIF":2.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11550758","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148442898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fast Inter-Enclave Communication Encryption","authors":"Pouria Peykani Sani;Ali Mohammadpur-Fard;Shamiek Mangipudi;Sina Darabi;Francesco Regazzoni;Patrick Eugster","doi":"10.1109/LCA.2026.3671373","DOIUrl":"https://doi.org/10.1109/LCA.2026.3671373","url":null,"abstract":"Trusted execution environments (TEEs) provide applications – notably executing in third-party infrastructures like the cloud – with an encrypted and isolated execution space, decoupling programs and their data from other resident applications and privileged software (e.g., operating system and hypervisor). This confinement of trust to hardware significantly reduces the attack surface. However, distributed cloud applications deployed in TEEs often require frequent communication across worker nodes within a cluster. Ensuring the confidentiality, authenticity, and integrity of inter-TEE data exchanges necessitates secure communication channels, typically enforced through encryption that introduces I/O throughput bottlenecks. In this paper, we demonstrate that software-based encryption—relying solely on central processing unit (CPU) computation—fails to keep pace with the high-throughput interconnects between TEEs while consuming substantial CPU resources. To address this inefficiency, we propose a parallelized channel encryption hardware within the existing memory encryption engine (MEE). Initial experiments show that our approach has the potential to reduce communication channel encryption overhead to just a few CPU cycles resulting in orders of magnitude speedup over conventional software-based approaches.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"89-92"},"PeriodicalIF":2.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148478821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploration of Algorithm-Hardware Co-Design for Floating-Point Digital Compute-in-Memory","authors":"Xiaochen Peng;Haruki Mori;Abhiroop Bhattacharjee;Brian Crafton;Hidehiro Fujiwara;Kerem Akarvardar","doi":"10.1109/LCA.2026.3675952","DOIUrl":"https://doi.org/10.1109/LCA.2026.3675952","url":null,"abstract":"Digital compute-in-memory (DCIM) has emerged as a promising technique to accelerate deep neural networks by minimizing data-movement and performing near/in-memory computation. While floating-point (FP) arithmetic being widely used in modern AI workloads due to its numerical robustness, supporting FP-DCIM brings design challenges, including dynamic range management, accumulation precision, FP arithmetic strategies and overheads. To address these challenges, we developed hardware-accurate convolutional and fully-connected layer operators to precisely emulate the multiply-and-add (MAC) operation of FP-DCIM. This enabled end-to-end accuracy evaluation under specific hardware design choices along with their quantified impact on both numerical behavior and hardware efficiency. We conduct a comprehensive algorithm-hardware co-design exploration across diverse AI workloads to identify the optimal FP-DCIM architecture that minimizes hardware cost under strict accuracy constraints. Specifically, we show that product mantissa can be truncated to 14b and 12b for FP16-DCIM and FP8-DCIM respectively with no accuracy degradation, while incorporating rounding allows even lower bit-width. These observations further enable exponent-dependent MAC-skipping as an orthogonal iso-accurate strategy for additional energy savings. Hardware evaluation on 3nm FP16-DCIM macros indicates that combining the above strategies can reduce power by >37% without compromising accuracy performance.","PeriodicalId":51248,"journal":{"name":"IEEE Computer Architecture Letters","volume":"25 1","pages":"118-121"},"PeriodicalIF":1.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147665399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}