Graph-Based ECO and Patch Generation for High-Level Synthesis
For HLS designers, this work addresses the costly problem of late-stage design modifications by enabling efficient ECOs in Google XLS.
This paper introduces a graph-based ECO methodology for HLS that uses Graph Edit Distance to detect structural differences and generate patches, achieving high structural reuse and full functional correctness across several designs.
High-level synthesis (HLS) tools offer limited support for Engineering Change Orders (ECOs), making late-stage design modifications challenging and costly. This paper introduces a graph-based ECO methodology tailored for Google XLS. A Graph Edit Distance (GED) algorithm is used to detect structural differences between original and revised intermediate representations (IRs), which are then transformed into patch operations. A patch application mechanism is developed to enforce XLS IR constraints while preserving semantic correctness, together with a schedule constraining scheme that maintains the original pipeline registers. Experiments across several XLS designs demonstrate high structural reuse ratios, effective schedule preservation, and full functional correctness, highlighting the practicality of the approach for production HLS flows.