{"ok":true,"article":{"slug":"chorus-complementary-experts-for-high-coverage-testbench-stimulus-generation-0f102392","title":"CHORUS: Complementary Experts for High-Coverage Testbench Stimulus Generation","url":"https://arxiv.org/abs/2608.10090","canonical":"https://www.aimode.news/article/chorus-complementary-experts-for-high-coverage-testbench-stimulus-generation-0f102392","sourceName":"arXiv cs.AI","summary":"arXiv:2608.10090v1 Announce Type: new Abstract: Large language models (LLMs) have advanced code generation, where executable feedback provides a more reliable learning signal than textual imitation alone. Hardware verification is an important application of code generation and accounts for a substantial fraction of modern chip design effort, with high-coverage testbench stimulus generation as a key task. We present CHORUS, a post-training framework that pushes performance beyond what a conventional supervised fine-tuning (SFT)-to-reinforcement learning (RL) pipeline achieves. CHORUS builds on two observations. First, staged SFT produces behaviorally diverse checkpoints, and dense-reward RL turns them into strong experts with comparable aggregate performance but distinct task-level strengths. Second, these complementary strengths can be exploited through either training-free model merging or further post-training to outperform the best individual expert. By consolidating the resulting specialists into a single 4B model, CHORUS achieves 88.0% Pass@1 on CVDP-ECov, outperforming DeepSeek-R1 (671B) by 13.5 percentage points.","category":"AI","image":null,"lang":"en","publishedAt":"2026-08-12T04:00:00+00:00","createdAt":"2026-08-13T02:00:13.630313+00:00"}}