CD4LM: Consistency Distillation and aDaptive Decoding for Diffusion Language Models

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Liang, Yihao, Wang, Ze, Chen, Hao, Sun, Ximeng, Wu, Jialian, Yu, Xiaodong, Liu, Jiang, Barsoum, Emad, Liu, Zicheng, Jha, Niraj K.
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915708734013440
author Liang, Yihao
Wang, Ze
Chen, Hao
Sun, Ximeng
Wu, Jialian
Yu, Xiaodong
Liu, Jiang
Barsoum, Emad
Liu, Zicheng
Jha, Niraj K.
author_facet Liang, Yihao
Wang, Ze
Chen, Hao
Sun, Ximeng
Wu, Jialian
Yu, Xiaodong
Liu, Jiang
Barsoum, Emad
Liu, Zicheng
Jha, Niraj K.
contents Autoregressive large language models achieve strong results on many benchmarks, but decoding remains fundamentally latency-limited by sequential dependence on previously generated tokens. Diffusion language models (DLMs) promise parallel generation but suffer from a fundamental static-to-dynamic misalignment: Training optimizes local transitions under fixed schedules, whereas efficient inference requires adaptive "long-jump" refinements through unseen states. Our goal is to enable highly parallel decoding for DLMs with low number of function evaluations while preserving generation quality. To achieve this, we propose CD4LM, a framework that decouples training from inference via Discrete-Space Consistency Distillation (DSCD) and Confidence-Adaptive Decoding (CAD). Unlike standard objectives, DSCD trains a student to be trajectory-invariant, mapping diverse noisy states directly to the clean distribution. This intrinsic robustness enables CAD to dynamically allocate compute resources based on token confidence, aggressively skipping steps without the quality collapse typical of heuristic acceleration. On GSM8K, CD4LM matches the LLaDA baseline with a 5.18x wall-clock speedup; across code and math benchmarks, it strictly dominates the accuracy-efficiency Pareto frontier, achieving a 3.62x mean speedup while improving average accuracy. Code is available at https://github.com/yihao-liang/CDLM
format Preprint
id arxiv_https___arxiv_org_abs_2601_02236
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle CD4LM: Consistency Distillation and aDaptive Decoding for Diffusion Language Models
Liang, Yihao
Wang, Ze
Chen, Hao
Sun, Ximeng
Wu, Jialian
Yu, Xiaodong
Liu, Jiang
Barsoum, Emad
Liu, Zicheng
Jha, Niraj K.
Computation and Language
Autoregressive large language models achieve strong results on many benchmarks, but decoding remains fundamentally latency-limited by sequential dependence on previously generated tokens. Diffusion language models (DLMs) promise parallel generation but suffer from a fundamental static-to-dynamic misalignment: Training optimizes local transitions under fixed schedules, whereas efficient inference requires adaptive "long-jump" refinements through unseen states. Our goal is to enable highly parallel decoding for DLMs with low number of function evaluations while preserving generation quality. To achieve this, we propose CD4LM, a framework that decouples training from inference via Discrete-Space Consistency Distillation (DSCD) and Confidence-Adaptive Decoding (CAD). Unlike standard objectives, DSCD trains a student to be trajectory-invariant, mapping diverse noisy states directly to the clean distribution. This intrinsic robustness enables CAD to dynamically allocate compute resources based on token confidence, aggressively skipping steps without the quality collapse typical of heuristic acceleration. On GSM8K, CD4LM matches the LLaDA baseline with a 5.18x wall-clock speedup; across code and math benchmarks, it strictly dominates the accuracy-efficiency Pareto frontier, achieving a 3.62x mean speedup while improving average accuracy. Code is available at https://github.com/yihao-liang/CDLM
title CD4LM: Consistency Distillation and aDaptive Decoding for Diffusion Language Models
topic Computation and Language
url https://arxiv.org/abs/2601.02236