Information-Guided Frontier Decoding: Contextual Utility-Driven Commitment in dMLLMs

Xingyou Fang, Jingxing Zhong, Xiaosong Yuan, Xiaofeng Zhang


Abstract
Decoding quality in diffusion multimodal language models (dMLLMs) depends heavily on the order in which masked tokens are committed. Existing confidence-based strategies prioritize locally easy tokens, but confidence does not necessarily reflect contextual usefulness. As a result, structurally easy tokens such as punctuation may be committed before informative semantic anchors, weakening context propagation and increasing error accumulation. We propose Information-Guided Frontier Decoding (IGFD), a training-free decoding strategy that ranks candidates using token confidence, neighborhood uncertainty, and structural commitment risk. IGFD encourages early commitment of reliable semantic anchors while delaying fragile structural tokens, improving contextual support during decoding. A dynamic candidate frontier further constrains token selection to locally expandable regions under the same decoding budget. The method requires no additional training, auxiliary models, or extra forward passes. Experiments across multimodal understanding, reasoning, grounding, and hallucination benchmarks show that IGFD consistently outperforms existing decoding strategies across the majority of benchmarks and diffusion MLLM backbones under identical decoding budgets.
Anthology ID:
2026.findings-emnlp.589
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
12422–12435
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URL:
https://aclanthology.org/2026.findings-emnlp.589/
DOI:
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Cite (ACL):
Xingyou Fang, Jingxing Zhong, Xiaosong Yuan, and Xiaofeng Zhang. 2026. Information-Guided Frontier Decoding: Contextual Utility-Driven Commitment in dMLLMs. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 12422–12435, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Information-Guided Frontier Decoding: Contextual Utility-Driven Commitment in dMLLMs (Fang et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.589.pdf