OpenROAD and the Era of Agents
Andrew B. Kahng��University of California, San Diego
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Outline
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The agentic lever (LLMs 🡪 Agents 🡪 R&D Acceleration )
From “EDA tools” to “EDA R&D collaborators”
IC design �optimization �(PPA, schedule, cost)
LLMs + tool use
EDA = tools �(synthesis, P&R, STA, etc.)
(Human +) Agentic R&D loop�(read logs, tweak params, edit code, check/eval + iterate)
Multi-hours/multi-days reasoning
Comprehend large codebases
Invoke tool commands
Self iteration with feedback
LLMs in EDA (2026 ++)
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From assistance to autonomy: two levels
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OpenROAD as a foundation for agentic EDA research
Code-level��GR-evolve 🡪 grt��HELIX 🡪 dpl, gpl��AuDoPEDA 🡪 dpl, gpl, rsz
Flow-level��ORFS-Agent �🡪 flow knobs
Assistants ��OR-Assistant, OpenROAD-Agent 🡪 scripts + user queries�
Open code
Open APIs
Open benchmarks
“~13% WL/ECP gains, 40% fewer iterations”
94% pass-rate vs. 0% for foundational models”
Up to 9% HPWL, 23% RWL reduction across 2 PDKs
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Three frontiers of recent progress in OpenROAD
“~40% fewer iterations than autotuners”
“~19% power gains”
“~9% HPWL gains”
Flow tuners
Repo-scale coding
Bespoke, design-adaptive tools
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Outline
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Evolving placement and routing in OpenROAD
Synthesis
Floorplan
GPL
DPL
CTS
GRT
DRT
Coding evolution targets
HELIX
GR-Evolve
Attributes | HELIX (placement) – UCSD | GR-Evolve (routing) – ASU |
Target | Global + detailed placement (gpl, dpl) | Global routing (grt) |
Method | (μ+λ) evolutionary search with literature-guided operators | Stateless agentic loop with persistent QoR history |
Knowledge base | 97 papers + documentation + pseudocode + parameter list | Distilled router summaries + source |
Key results | 9% HPWL and 23% RWL (max) �4.5% / 5.6% geomean | 8.7% post-DR WL (max) |
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Repository-grounded coding agents for OpenROAD
Repo graph + documentation
Literature-grounded planning
Plan localization �(map plan to edit surfaces)
Autonomous execution loop �(apply diffs, build, run flow, measure QoR)
Formal diff checking �(Lean; Aristotle; AXLE)
Target | Module(s) | | Diff scope |
Routed wirelength | dpl | -5.4% | 11 files, ~1k LoC |
Effective clock period | gpl, rsz | -10.0% | 11 files, ~330 LoC |
Total power | rsz | -19.4% | 9 files, ~1k Loc |
Removing any single stage dramatically reduces valid diff-rate!
No execution loop
Full system
No documentation
No formal gate
No localization
No planning
92/100
54/100
44/100
41/100
37/100
26/100
Valid diffs out of 100 trials
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ORFS-agent – LLM-driven flow autotuning
Comparison of ORFS-agent and OR-AutoTuner w.r.t. wirelength and ECP
Normalization: Results with OR-AT4 params and 375 iterations set as 1.0
Baseline: OR-AT �(4 vars, 375 iters) ≡ 1.0
ORFS-agent uses ~40% fewer iterations, iso-QOR
Also: ≈ 13% gains in WL or ECP (single-objective) �(details: MLCAD25 paper)
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Improving a SOTA Hypergraph Partitioner (OpenROAD/par)
Kahng talk 20251020
Titan23 suite, LLM-evolved diff
Cut reduction (%) vs. TritonPart
K = 2
K = 3
K = 4
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Outline
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Challenge 1: validation & evaluation
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Challenge 2: humans + agents; IP & creators’ rights
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Challenge 3: project & ecosystem governance
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Toward an open vertical environment for EDA agents
Environment scaffolding�(The substrate agents act inside) | Agent capabilities�(What we want agents to do) | Ecosystem and governance (What OpenROAD can achieve) |
Episode schema for EDA (workspace, actions, constraints, QoR) | Lexicographic, constraint-aware rewards (hard gates 🡪 QoR frontier 🡪 cost)� | Open evolving agent benchmark suite |
Cross-stage state & observability (RTL ↔ verif ↔ synth ↔ PD ↔ signoff causality) | Cross-tier orchestration (flow-level + code-level in one loop) | Reproducibility manifests�(pinned commits, PDKs, agent versions, prompts) |
Multi-fidelity ladder (lint 🡪 sim 🡪 synth 🡪 PD 🡪 signoff audit) | Trajectory-grounded training + research-grade memory | CI-enforced QoR gates + machine-checkable invariants |
Fast learned surrogates as first-class env citizens | Code-level R&D | Industrial calibration loop + compute equity |
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Thank You!
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Flow-level agents – architecture
High-level objective�“Minimize ECP with < 2% PDP degradation”
LLM planner
Execution layer
EDA tools
LLM
Feedback
Knowledge�corpus
Treat EDA tools as black-boxes; LLM decomposes objective into subtasks; each subtask is translated to scripts
Response
Query
Query
Response
Invoke
PPA
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Code-level agents – architecture
High-level objective�“Reduce HPWL by improving global swap operator in OpenROAD’s dpl”
Code parser
LLM reasoner
Compiler + regression tests
EDA tools
QoR metrics
Feedback
Feedback
Modify internal heuristics and algorithms; LLM reads, proposes and edits code diffs
LLM
Query
Response
Response
Query
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AuDoPEDA: Documentation 🡪 Planning 🡪 Diff 🡪 QoR Loop
Convert codebase to structured knowledge
Planning is typed and validated
Converts research intent into executable diffs
Accept only if QoR improves
QoR
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A merge-ready OpenROAD PR (agent-driven)
What “merge-ready” requires
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Links
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Hypergraph partitioning – beyond quality: speed
Same cutsize with significantly faster runtime!
Better cutsize than TritonPart
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