Home SystemVerilog How To Validate Type-Casting In OVM-e

Search

How To Validate Type-Casting In OVM-e PDF Print E-mail
User Rating: / 0
PoorBest 
Thursday, 24 December 2009 16:37

Before type-casting an e variable ("as_a"), we often want to check the validity of the operation (this is quite similar in concept to $cast in SystenVerilog). The reason is simple, in case the casting operation failed we would end up with a fatal error at run-time that otherwise could have been avoided. But how?

 

Here's one elegant way to do it:

type ttt: [E1=3, E2=10];
extend sys {
 run() is also {
 var x: byte = 3; // try x=7 too
  if x.as_a(ttt) in all_values(ttt) then { out( *** X IS IN RANGE *** ) };
 };
 };

In this small example we were trying to convert (type-cast) x from byte to ttt. The method all_values() returns a list of all possible scalar types (in our case - for type ttt). Try this code with x=3 and with x=7 and see what happens.

 

 
More articles :

» Specman GUI Trick

If you’re using Specman GUI to run simulations you must have encountered this rather annoying feature before - When running several simulations during the same session, specman doesn’t clear the log file by default so what you get in the end is...

» Prepare For Your Next Job Interview

Succeeding at job interviews requires practice. If you're applying for a verification job you'd better get yourself well prepared both mentally and technically. Nevertheless, a great deal of tension could be avoided if you knew in advance what sort...

» The Easy Way To Start Using OVM-e Sequences

Industry-standard methodologies are great, really. It would be so nice if our entire verification environment (VE) were OVM-e (eRM) compliant, wouldn’t it? But what if there are legacy components in our env that don’t follow any specific...

» Let The New Game Begin

Things are changing. The EDA industry is changing, and the verification world is changing (check out Janick Bergeron's inspiring at SNUG San Jose for a glimpse of the future of verification). One of the major challenges we’re already facing today...

» Ignorance Is A Bliss

There is a rather confusing feature in Specman’s coverage engine that I would like to share with you today. I’ve met several people (including myself) who had been struggling to understand what was going on there and gave up Recently I was...

Add comment


Security code
Refresh

Copyright © 2017 Think Verification - Tips & Insights on ASIC Verification. All Rights Reserved.
Joomla! is Free Software released under the GNU/GPL License.