Why there are different results in Synplify and Leonardo?

[jacklalo020]

precision rtl synplify comparison

Hi all,
I used synplify pro and leonardo spectrum to synthesis a design and every time i did that, for small pices of VHDL code or a large design, the maximum frequency evaluated by synplify was greater than the one leo give. I know that's only an evaluation that don't take in account other delays, but since we are dealing with the same project (the ressources used are mearly the same) why do they differ????Is there any way to have better results in leonardo????

 

[eda_wiz]

Synplify vs leonardo?

Hi
The Max Frequency given by synplify is higher bcoz it has a better synthesis algorithm compared to Leonardo... (thats why synplify is more popular than Leonardo) If u need to use mentor synthesis itself.. try the latest one "Precision RTL" ..


Also .. make sure you are giving the same synthesis constraints in both tools...
like compile effort..., optmization time ... and synthsis library aimed at should be same

 

[Zerox100]

Re: Synplify vs leonardo?

I used them. Leonardo had some problem. For example its not fully customizable. Synplify is good tools, but it also had some problems that begaan when you try to PS sim. "Internal error" is one of them. It's an unknown error that i didn't know how to repair it.
Precision Synthesis was a crazy synthesis tools. It manigultaed my vectors and then all the design didn't work. It didn't have any good doc.

 

[ydao]

Re: Synplify vs leonardo?

On my view, Synplify is more easy to use, just so.
If your master the many synthesis commands of Leo, maybe you could find how it is powerful.

 

[saker]

Re: Synplify vs leonardo?

Don't believe any of the results predicted by the synthesis tools alone I have seen them predict performance that is twice as good as is achievable in the actual part (Xilinx vertex E)and at other times their reported timing is way to pessimistic (Altera Stratix GX) ....
Here is at least one case to illustrate why the Synplify/leonardo estimates may not be correct. Synplify does not have correct timing models for Altera memories. The timing through a memory path assumes a default set of timing values.

The real timing is what comes out of the vendor's Place and route tool
Saker

 

[henrik2000]

Re: Synplify vs leonardo?

I do agree with saker. Timing is only an very rough approximation. Only at physical level this can be precisely evaluated. As far as comparaison between Actel and Leonardo is concerned, I use both.. And I have to admit that not only timing is different, but implementation as well differ for a specific same source verilog code. It would seem logical to think that Synplify used with amplify would gives better results if the target is an Actel part.
May be someone could convince both software manufacturer to adjust their 'timing'..

All depends if your design is few thousand gates or few hundred thousand gates..

 

[henrik2000]

Re: Synplify vs leonardo?

I do agree with saker. Timing is only an very rough approximation. Only at physical level this can be precisely evaluated. As far as comparaison between Actel and Leonardo is concerned, I use both.. And I have to admit that not only timing is different, but implementation as well differ for a specific same source verilog code. It would seem logical to think that Synplify used with amplify would gives better results if the target is an Actel part.
May be someone could convince both software manufacturer to adjust their 'timing'..

All depends if your design is few thousand gates or few hundred thousand gates..

 

[vvsvv]

Synplify vs leonardo?

I like Lenardo more,
It works so easy and have a good efficiency!
and the systhesis result is good too.

 

[delay]

Re: Synplify vs leonardo?

How'd you guys take into account FPGA Express by Synopsys and XST by Xilinx in this comparison? i.e.,

Leonardo vs. Synplify Pro vs. FPGA Design Compiler vs. XST


Thanks,

delay (delay by technology)

 

[bibo1978]

Re: Synplify vs leonardo?

from FPGA point of view I believe Synplify is much better than LS, even if you master the constraint entry of LS, I believe that this is mainly due to some major defects in the way LS optimize your design, for example it removes all equivalent logic even if you used the don't touch constraint, unless you declared multiple signals and each signal should also have its don't touch attribute, unlike synplify which you can with small tricks do what you want and the tool obeys your constraint.
I believe that this is the reason for synplify merit in speed "you can control it more precisely and easily"
However, if you don't have except LS then you should take care of the LS general errors when you are writing your HDL code.

 

[dspusr]

Synplify vs leonardo?

LS is a dead soft ware.

 

[yangvic]

Synplify vs leonardo?

Yes,Mentor have a new systhesis tool, PRECISION PHYSICAL .

 

[hock]

Re: Synplify vs leonardo?

i think roli had asked all of us to stop such topics. they have been discussed many times om this board
hock

 

[Ohh2]

Re: Synplify vs leonardo?

I use both of them (Synplify and LeonardoSpectrum/Precision Synthesis)

 

[amarnath]

Synplify vs leonardo?

synplify comes first and then leonardo spectrum...

 

[Petrovna]

Re: Synplify vs leonardo?

new d/l Synplify and more

https://www10.edacafe.com/link/display_new_popular.php?type=new

 

[huster]

Synplify vs leonardo?

The market is always right.You can see the market share.