What problem does it solve? Fixing a bug after place-and-route is risky and expensive: a full re-synthesis and P&R re-run can blow schedules, while an ad-hoc patch can silently break timing or consume spare cells needed later. This Skill produces a structured ECO plan that classifies the change, checks spare-cell feasibility, and defines the regression tests that must re-run. ## Core Features & Use Cases - ECO classification and triage: Distinguishes metal-only ECOs (re-route only) from base-layer ECOs (cell changes) and estimates gate delta, risk level, and timing impact. - Spare-cell planning: Maps required logic to nearby spare cells and enforces preservation of unused keep-marked spares for future ECOs. - Guarded iteration loops: Drives ECO variant sweeps through shared convergence and admission-guard primitives so retries are deduplicated and budget-capped. - Use Case: A bug is found two weeks before tape-out in an already-routed design. Use this Skill to determine whether the fix can be metal-only, which spare cells to wire up, and which gate-level simulations and STA checks must re-run. ## Quick Start Ask the assistant to plan an ECO for a bug found after place-and-route, providing the affected module, the post-P&R netlist, and whether only metal-layer changes are allowed.
