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

CTS only builds the clock tree of the *current* mode

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#11,273 0 comments 0 reactions 1 assignee View on GitHub

@arthurjolo is already working on this.

Since Sep 2, 2026.

cts
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Description

Describe the bug

clock_tree_synthesis discovers clock roots from the SDC of sta's current mode
only. In a multi-mode design the clock ports that belong to the other modes are
left completely unbuffered, and latency balancing never sees the imbalance those
modes contain.

Expected Behavior

Support for multi-mode CTS

Environment
153b1801a09b00a8be85157cf6f67cdb914e26ae
To Reproduce

multi_mode_cts.tar.gz

openroad -no_init -exit multi_mode_cts.tcl
Relevant log output

Screenshots

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Additional Context

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