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Tobias Strauch

10/23/2021, 10:39 AM
I'm wondering if the max fanout default = 5 setting is considered at all. For example, the default regression output of the zipdiv design shows fanouts > 10 (for all synthesis results): Report: _2003_: 65 Report: _1968_: 68 Report: _0081_: 32 Report: pre_sign: 68 Report: r_busy: 65 Eventually the reason for the slow design performance. I see similar problems on other designs.
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Vijayan Krishnan

10/23/2021, 10:43 AM
Its initial run. During resizer design those high fanout values will be optimized as per given value.
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Tobias Strauch

10/23/2021, 10:44 AM
So zipdiv.synthesis_preroute.v is not the golden netlist after abc fanout optimization ?
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Vijayan Krishnan

10/23/2021, 10:58 AM
Please file a GitHub issue with source files and logs
as per configuration files standard cells fanout should be 6 and clock buffer fanout is 20. If its more than that design not optimized properly