The-OpenROAD-Project / The-OpenROAD-Project/OpenROAD

DRT: large runtime due to multiple repair_antennas iterations

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#11,140 3 comments 0 reactions 1 assignee View on GitHub

@jfgava is already working on this.

Since Sep 17, 2026.

drt waiting on op
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Description

DRT is currently struggling to converge due to multiple iterations of antenna repair for sky130hd Microwatt.
This seems to be related to long nets going around the macros.
I can see some cases where DRT is doing a lot of detours not following the GRT guides near the macros.

The figure below shows a strange scenario where a clock net goes up, down, and up again in DRT (not following the grt guides). Note that there is a large macro aligned to the right corner.

Image

Zoom at the bottom:

Image

And here another example of a long net goind around the macro, requiring multiple diodes to fix antenna issues:

Image

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