SV constraint program for shuffle

Here is the program to generate random array of signed integers which is shuffle of another random array.  This exhibits significance of array methods like sum,product or xor in the constraint.



class cfg_c;
  rand int signed A[];
  rand int signed B[];
 
  constraint A_B_size_cnstr{
    A.size() inside {[4:5]}; // can modify this
    B.size() == A.size();
  }
 
  constraint B_elements_cnstr{
    solve A.size() before A;
    solve B.size() before B;
    foreach(B[i])
      B[i] inside {A};    
    B.sum() == A.sum();
    (B.xor() ^ A.xor()) == 0;
    B.product() == A.product();
  }
endclass : cfg_c

module test;
  cfg_c cfg;
  initial begin
    cfg = new();
    repeat(10) begin
               cfg.randomize();
               $display("After randomization..");
               foreach(cfg.A[i])
                              $display("A[%0d] = %0d :: B[%0d] = %0d", i, cfg.A[i], i, cfg.B[i]);
    end
  end
endmodule : test

Result:-

After randomization..

A[0] = -2061227070 :: B[0] = -945796533

A[1] = 577051819 :: B[1] = -287061759

A[2] = -945796533 :: B[2] = 577051819

A[3] = -287061759 :: B[3] = -2061227070

A[4] = -1856519535 :: B[4] = -1856519535