Synplify pro output bigger?...

[davorin]

Is it possible that synplify pro produces larger output than quartus?

Just compared a cpu core where it takes up 5439 LEs inside QII version 4.0sp1 but 6060 LEs in Synplify Pro 7.5?

 

[huster]

I think it is possible.Synplify Pro is not always the best.

 

[davorin]

FPGA compiler seems to be better...though haven't tested in FPGA...same core uses 4974 LEs...

 

[saker]

Sorry for the late response....

It looks like Synplify changed something in the 7.5 release of synplify Pro we found that some designs that compiled and fit in the Stratix device using Synplify Pro 7.33 no longer fit when synthesized using 7.5!... So some of us are using the older version......
Having said that I should mention that I just had a design that Synplify Pro 7.33 was still trying to synthesize after 16 hours.... I isolated the problem modules, made them black boxes to synplify and then fed them into quartus and allowed Quartus to synthesize that section before doing the place and route.

Saker

 

[yeewang]

Every synthesizer has its own algorithm for specific designs. so keep in mind the result's always design-dependent.

 

[hock]

the most probable reason is that altera has not shared all the chip related information with other eda venders. quartus has more detail information about internal working of altera chips hence it can use better optimisation algorithms.

hock

 

[saker]

If you go back and read my post you will see that the design fit when synthesized with Synplify pro 7.33 but did not when synthesized with 7.51...
The comparison was Synplify pro 7.33 vs 7.51, not Synplify vs Quartus for synthesis.
These results clearly do not have anything to do with Altera "not sharing" info with Synplicity.

Saker

 

[hock]

i had repplied to the original qustion by davorin.
hock
Is it possible that synplify pro produces larger output than qu@rtus?

Just compared a cpu core where it takes up 5439 LEs inside QII version 4.0sp1 but 6060 LEs in Synplify Pro 7.5?

 

[vvsvv]

I think that you may try Len@rdo, if it's output is bigger than qu@rtus too, than may confirm that it is not the synthesiser bad!

^_^