How do we define Weighted Distribution Constraint in SystemVerilog

 In SystemVerilog how do we define constraint to have values a higher probability than others?

For this we use an Weighted Distribution concept using "dist"  syntax

For e.g

   class Transcation;

                 rand bit [1:0]     src_addr, dst_addr;

                 constraint  c_distribution  {

                             src_addr   dist   { 5 := 2, [7:9] := 3};

                             dst_addr  dist    { 5: /2 ,  [7:9] : /3};

                   }

    endclass


The above two expression  '5:=2'  and '5:/2' are equivalent

[7:9] := 3 says to make the weight for each value in the range equal to 3

[7:9] :/3  says to divide the weight across each value in the range



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