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Method Manipulation In SV and e PDF Print E-mail
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Thursday, 24 December 2009 16:46

If you're familiar with SystemVerilog and taking your first steps in e (or vice versa) you might find this useful. Here are some of the most common method manipulations that you''ll need to master and how you should go about implementing them in e and SV:

 

Before we dive in - here's the reference code for the examples we're going to show you.

// ** e **
struct my_struct {
 my_function() is {};
 my_task1()@sys.any is {};
 my_task2()@sys.any is {};
 };
// ** SystemVerilog **
class parent;
 // must be virtual
 virtual function my_function();
 endfunction
 virtual task my_task1();
 endtask
 virtual task my_task2();
 endtask
 endclass

OK, now let''s see how to implement the most common method manipulations in each language:


Extending methods - adding more functionality at the end:

// ** e **
 extend parent {
 my_function() is also {
 j++;
 };
 };
 
 // ** SV **
 class child extends parent;
 virtual function my_function();
 super.my_function();
 j++;
 endfunction;
 endclass


Extending methods - adding stuff to the beginning of a method:

// ** e **
 extend parent {
 my_function() is first {
 j++;
 };
 };
 
 // ** SV **
 class child extends parent;
 virtual function my_function();
 j++;
 super.my_function();
 endfunction;
 endclass


Overriding a method:

// ** e **
 extend parent {
 my_function() is only {
 j++;
 };
 };
 
 // ** SV **
 class child extends parent;
 virtual function my_function();
 j++;
 endfunction;
 endclass


Launching parallel threads - parent process not blocked:

// ** e ** 
 foo()@sys.any is {
 start my_task1();
 start my_task2();
 };
 
 // ** SV **
 task foo();
 fork begin 
 my_task1();
 my_task2();
 join_none; 
 endfunction


Launching parallel threads - parent process blocked until shortest thread completes:

// ** e ** 
 foo()@sys.any is {
 first of {
 { my_task1(); };
 { my_task2(); };
 };
 };
 
 // ** SV **
 function foo();
 fork begin 
 my_task1();
 my_task2();
 join_any;
 disable fork;    // remove if you don''t want to kill the longer task prematurely
 endfunction


Launching parallel threads - parent process blocked until all threads are finished:

// ** e ** 
 foo()@sys.any is {
 all of {
 { my_task1(); };
 { my_task2(); };
 };
 };
 
 // ** SV **
 function foo();
 fork begin 
 my_task1();
 my_task2();
 join;
 endfunction

 

 
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Comments  

 
0 #1 2010-04-17 16:43
Very simple and very informative article.
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