( ESNUG 353 Item 6 ) --------------------------------------------- [5/24/00]
Subject: ( ESNUG 348 #5 ) SDF & `resetall & `uselib & VCS & Verilog-XL
> It appears that with VCS a `resetall compiler directive causes the search
> path for levels below the current hierarchy to be a empty set. This
> applies to all files except those in the current file. Verilog-XL does
> not change search enviornment as a result of `resetall.
>
> Verilog-XL and VCS behave differently in another way. I've found that
> with Verilog-XL when a uselib directive is used in a model that
> instantiates parts, all searches at that level will honor that uselib
> statement. In other words, if a module instantiates parts and uses a
> `uselib statement to control the search path, then all searches at that
> level will use that search path until another uselib statement is
> encountered. For example, suppose I had a module in a `uselib enviornment
> of liba (`uselib dir=liba libext=.v) and suppose I instantiate two parts:
> a1 and b1. If I put a `uselib statement inside the code for a1 to control
> the search for sub-part a11, then all parts at the second hierarchical
> level would use the second enviornment. In other words part b11 which is
> instantiated by part b1 which is in the top level search enviornment will
> ONLY be searched in the second level enviornment that the uselib statement
> in a1 specified.
>
> Interestingly enough VCS5.1 behaves identically, but VCS5.0 maintains the
> top level environment for the second part.
>
> - John Russo
> Lucent Technologies Allentown, PA
From: John Russo
John,
Here is an update on ESNUG 348 #5 about VCS. One of the Lucent guys dealt
with this and wrote me:
I have been working with Synopsys to resolve the problem. At this point
Synopsys has acknowledged, found, and fixed the problem in VCS 5.1 and
5.2. Patch releases are available for both VCS 5.1 and 5.2. Furthermore,
Synopsys has agreed to raise this issue, along with related issues I found
while creating test cases for this problem, to OVI for standardization.
However, I recently discovered another bug in both VCS 5.1 and VCS 5.2
with SDF. Synopsys is currently working on the problem and will notify us
when a patch is ready. Synopys staff recommends the use of the +oldsdf
command line option until the bug is fixed.
Hope this helps others out there using VCS.
- John Russo
Lucent Technologies Allentown, PA
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