Diffusion-State Policy Optimization for Masked Diffusion Language Models
On the map: Diffusion models → Discrete and text diffusion
Abstract (arXiv)
Masked diffusion language models generate text through iterative masked-token filling, but terminal-only rewards on final completions provide coarse credit assignment for the intermediate filling decisions that shape the generation process. We propose Diffusion-State Policy Optimization (DiSPO), a plug-in credit-assignment layer that directly optimizes intermediate filling decisions. At selected intermediate masked states, DiSPO branches by resampling the currently masked positions from rollout-cached logits, scores the resulting completions, and updates only the newly filled tokens, requiring no additional multi-step diffusion rollouts or optimizer steps. We formalize a fixed-state objective for branched completions and derive a policy-gradient estimator that reuses the same rollouts as terminal-feedback policy optimization. Experiments on LLaDA-8B-Instruct show that DiSPO consistently improves terminal-feedback baselines, including diffu-GRPO and SPG, on math and planning benchmarks under matched rollout compute and optimizer steps, supporting its use as a general plug-in for masked diffusion policy optimization. Our project page is available at https://daioba.github.io/dispo .
Key facts. Cited by 3 papers in the map (data through 7 Oct 2026). Placed in Discrete and text diffusion, one of 14 directions in Diffusion models. Builds on 30 of its 33 references that are in the map. First posted on arXiv 6 Feb 2026.
Builds on
30 of 33 references.
Closest ancestors · 15
Same direction, newest first
- 2025SPG: Sandwiched Policy Gradient for Masked Diffusion Language Models10 Oct
- 2025Improving Reasoning for Diffusion Language Models via Group Diffusion Policy Optimization9 Oct
- 2025DiFFPO: Training Diffusion LLMs to Reason Fast and Furious via Reinforcement Learning2 Oct
- 2025Taming Masked Diffusion Language Models via Consistency Trajectory Reinforcement Learning with Fewer Decoding Step28 Sep
- 2025d2: Improving Reasoning in Diffusion Language Models via Trajectory Likelihood Estimation25 Sep
- 2025Dream 7B: Diffusion Large Language Models21 Aug
- 2025MDPO: Overcoming the Training-Inference Divide of Masked Diffusion Language Models18 Aug
- 2025wd1: Weighted Policy Optimization for Reasoning in Diffusion Language Models7 Jul
- 2025DiffuCoder: Understanding and Improving Masked Diffusion Models for Code Generation25 Jun
- 2025Plan for Speed: Dilated Scheduling for Masked Diffusion Language Models23 Jun
- 2025dKV-Cache: The Cache for Diffusion Language Models21 May
- 2025Block Diffusion: Interpolating Between Autoregressive and Diffusion Language Models12 Mar
3 more
Other references · 15
- 2022Training language models to follow instructions with human feedbackcited by 15,712
- 2017Proximal Policy Optimization Algorithmscited by 14,441
- 2021Training Verifiers to Solve Math Word Problemscited by 9,743
- 2024DeepSeekMath: Pushing the Limits of Mathematical Reasoning in Open Language Modelscited by 8,851
- 2023Let's Verify Step by Stepcited by 3,598
- 2020Learning to summarize from human feedbackcited by 2,562
- 2015Trust Region Policy Optimizationcited by 2,503
- 2019Fine-Tuning Language Models from Human Preferencescited by 2,124
- 2021Structured Denoising Diffusion Models in Discrete State-Spacescited by 1,665
- 2025s1: Simple test-time scalingcited by 1,311
- 2025Fast-dLLM: Training-free Acceleration of Diffusion LLM by Enabling KV Cache and Parallel Decodingcited by 404
- 2025d1: Scaling Reasoning in Diffusion Large Language Models via Reinforcement Learningcited by 178
3 more
Built on by
Citing papers per year: 2026: 3.
3 papers.
- 2026A Continuous-Time Reinforcement Learning Framework for Fine-Tuning Discrete Diffusion Modelscited by 1
- 2026CT-OPD: Counterfactual Trace On-Policy Distillation for Diffusion Vision-Language Modelscited by 0
- 2026Exploring More, Reasoning Better: Stepwise Risk-Sensitive GRPO for Diffusion Language Modelscited by 0
- 2026Exploring More, Reasoning Better: Stepwise Risk-Sensitive GRPO for Diffusion Language Models30 Sep 2026
- 2026CT-OPD: Counterfactual Trace On-Policy Distillation for Diffusion Vision-Language Models26 Sep 2026
- 2026A Continuous-Time Reinforcement Learning Framework for Fine-Tuning Discrete Diffusion Models16 Jul 2026
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- 2026OPTD: On-Policy Transition Distillation with Consistency-Guided Adaptive Compression for Few-Step Diffusion Language Models
- 2026Beyond Masks: Efficient, Flexible Diffusion Language Models via Deletion-Insertion Processes
- 2025On Powerful Ways to Generate: Autoregression, Diffusion, and Beyond
- 2026Parallelism and Generation Order in Masked Diffusion Language Models: Limits Today, Potential Tomorrow