Beyond Tokens: Semantic-Aware Speculative Decoding for Efficient Inference by Probing Internal States
Centre for Software Excellence, Huawei, Canada(华为加拿大软件 excellence 中心);Department of Computer Science, University of Manitoba, Canada(曼尼托巴大学计算机科学系);School of Computing, Queen’s University, Canada(皇后大学计算学院)
Ximing Dong, Shaowei Wang, Dayi Lin, Boyuan Chen, Ahmed E. Hassan
Large Language Models (LLMs) achieve strong performance across many tasks but suffer from high inference latency due to autoregressive decoding. The issue is exacerbated in Large Reasoning Models (LRMs), which generate lengthy chains of thought. While speculative decoding accelerates inference by drafting and verifying multiple tokens in parallel, existing methods operate at the token level and ignore semantic equivalence (i.e., different token sequences expressing the same meaning), leading to inefficient rejections. We propose SemanticSpec, a semantic-aware speculative decoding framework that verifies entire semantic sequences instead of tokens. SemanticSpec introduces a semantic probability estimation mechanism that probes the model's internal hidden states to assess the likelihood of generating sequences with specific meanings. Experiments on four benchmarks show that SemanticSpec achieves up to 2.7x speedup on DeepSeekR1-32B and 2.1x on QwQ-32B, consistently outperforming token-level and sequence-level baselines in both efficiency and effectiveness.
Ouroboros: Generating Longer Drafts Phrase by Phrase for Faster Speculative Decoding
Institute for Artificial Intelligence(人工智能研究院);Department of Computer Science and Technology(计算机科学与技术系);Shanghai Artificial Intelligence Laboratory(上海人工智能实验室);ModelBest Inc.(模佰科技);Beijing National Research Center for Information Science and Technology(北京信息科学与技术国家研究中心);Tsinghua University(清华大学)
GliDe with a CaPE: A Low-Hassle Method to Accelerate Speculative Decoding
Singapore Management University(新加坡管理大学);National University of Singapore(新加坡国立大学);The Hong Kong Polytechnic University (PolyU)(香港理工大学);Harbin Institute of Technology (Shenzhen)(哈尔滨工业大学(深圳));Tencent AI Lab(腾讯AI Lab)
AdaSD: Adaptive Speculative Decoding for Efficient Language Model Inference
Institute of Information Science, Academia Sinica(学术院信息研究所);Department of Computer Science and Information Engineering, National Taiwan University(台湾大学计算机科学与信息工程系)
FlexDraft: Flexible Speculative Decoding via Attention Tuning and Bonus-Guided Calibration
EPIC Lab, SJTU(上海交通大学EPIC实验室);UESTC;School of Software Engineering, HUST(华中科技大学软件工程学院);Tsinghua University(清华大学);HKUST(GZ)(香港科技大学(广州));Shanghai AI Laboratory(上海人工智能实验室)
Self Speculative Decoding for Diffusion Large Language Models
School of AI, Shanghai Jiao Tong University(上海交通大学人工智能学院);University of Science and Technology of China(中国科学技术大学);Xidian University(西安电子科技大学);Shanghai AI Laboratory(上海人工智能实验室);Huawei Technologies Ltd.(华为技术有限公司)
DREAM: Drafting with Refined Target Features and Entropy-Adaptive Cross-Attention Fusion for Multimodal Speculative Decoding
Courant Institute of Mathematical Sciences, New York University(纽约大学数学科学学院);Tandon School of Engineering, New York University(纽约大学工程学院);Cerebras Systems Inc.(Cerebras Systems公司);University of Pennsylvania(宾夕法尼亚大学)
Mistletoe: Stealthy Acceleration-Collapse Attacks on Speculative Decoding
Harbin Institute of Technology, Shenzhen(哈尔滨工业大学(深圳));South China University of Technology(华南理工大学);Tsinghua Shenzhen International Graduate School, Tsinghua University(清华大学深圳国际研究生院);Huawei Technology(华为技术)
School of Artificial Intelligence, Wuhan University(武汉大学人工智能学院);School of Computer Science, Wuhan University(武汉大学计算机学院);School of Information Management, Wuhan University(武汉大学信息管理学院);School of Computer Science, Shanghai Jiao Tong University(上海交通大学计算机学院)
TETRIS: Optimal Draft Token Selection for Batch Speculative Decoding
Singapore-MIT Alliance for Research and Technology(新加坡-麻省理工联合研究技术联盟);Dept. of Computer Science, National University of Singapore(新加坡国立大学计算机科学系);CSAIL, Massachusetts Institute of Technology(麻省理工学院计算机科学与人工智能实验室)
AdaSpec: Adaptive Speculative Decoding for Fast, SLO-Aware Large Language Model Serving
Tongji University(同济大学);Shenzhen Research Institute of Big Data, The Chinese University of Hong Kong, Shenzhen(深圳大数据研究院,香港中文大学(深圳));Huazhong University of Science and Technology(华中科技大学);School of Data Science, The Chinese University of Hong Kong, Shenzhen(数据科学学院,香港中文大学(深圳))