YosysHQ / arachne-pnr

Place and route tool for FPGAs
MIT License
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Fix placement in carry chains with differing control signals #88

Closed daveshah1 closed 6 years ago

daveshah1 commented 6 years ago

This should fix issues #65 and #87, by breaking the carry chain if differing control signals are detected within the chain, so the parts with different signals can be packed into different LCs.

I have run some basic functional regression tests, but I would suggest leaving this PR open as I would like to run some further quality of result regression tests - and it would be great if anyone with large designs could test this.