What are the Phys Opt Design options?

[dwisehart]

What do the various options do?

Explore

AggressiveExplore

AlternateReplication

AggressiveFanoutOpt

AlternateDelayModeling

AddRetime

Default.

Regards,

Daniel

[vijayak · Accepted solution]

Hi,
Use the tcl command "phys_opt_design -help" in vivado Tcl console to know more.

* Explore - Run different algorithms in multiple passes of optimization,
including replication for very high fanout nets.

* ExploreWithHoldFix - Run different algorithms in multiple passes of
optimization, including hold violation fixing and replication for very
high fanout nets.

* AggressiveExplore - Similar to Explore but with different optimization
algorithms and more aggressive goals.

* AlternateReplication - Use different algorithms for performing critical
cell replication.

* AggressiveFanoutOpt - Uses different algorithms for fanout-related
optimizations with more aggressive goals.

* AlternateDelayModeling - Performs all optimizations using alternate
algorithms for estimating net delays.

* AddRetime - Performs the default phys_opt_design flow and adds register
re-timing.

* Default - Run phys_opt_design with default settings.

Refer to page 87 of http://www.xilinx.com/support/documentation/sw_manuals/xilinx2013_4/ug904-vivado-implementation.pdf

[siktap]

These are directives which control teh behavior of the commands. Each implementation command has a set of directives that could be applied to them. These are all explained in the UG904.

Chapter 2 goes over them. Further They is another flexibility given to user which are called strategies. These vary these specific directives for each command like place_Design or phys_opt design. These are described in the appendix solution of the UG.

http://china.xilinx.com/support/documentation/sw_manuals/xilinx2013_4/ug904-vivado-implementation.pdf 

[yiqi17]

Hi After running Phys_opt_design (from tcl script console), I do see the timing is improved, how can I update the bitstream from the new routing? (If I generate the bitstream agian, the timing shown is still the previous worse timing)

Thanks

[dwisehart]

This is an old topic and not really the same as your question. Probably better to start a new topic.