Home Specman / e 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 :

» Top 10 Verification Myths

Let’s unveil the truth behind some of the common myths out there!

» UVM Users: Here Are Some Great Tips [Video]

A couple of years ago I wrote here about how the UVM was becoming the next big thing in the verification world.And guess what? I was right. Not that it was too hard to predict... but anyway, the industry has finally standardized on language (SV) and...

» VMM Hackers Guide - Creating Smart Scenarios With Atomic Generators

VMM ships with some pretty useful built-in components and applications. VMM''s Atomic Generator is probably one of the most powerful ones, yet it's pretty basic. It can definitely help you generate a flow of random items but it was not intended for...

» We Hear Ya!

 During the last months we conducted a poll about what you guys would you like to read more about on ThinkVerification and here are the results: Verification Methodology - 41%SystemVerilog Tutorials - 31%e Tutorials - 13%Interviews - 12%...

» Plug, Play and Reuse!

Time to talk about module-to-system reuse, a very important topic. If you plan your verification environment properly (using one of the common methodologies in the market today or your own) you’ll be able to easily build a system level...

Add comment


Security code
Refresh

Copyright © 2018 Think Verification - Tips & Insights on ASIC Verification. All Rights Reserved.
Joomla! is Free Software released under the GNU/GPL License.