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//----------------------------------------------------------------------

//  Copyright (c) 2018 by Doulos Ltd.

//

//  Licensed under the Apache License, Version 2.0 (the "License");

//  you may not use this file except in compliance with the License.

//  You may obtain a copy of the License at

//

//  http://www.apache.org/licenses/LICENSE-2.0

//

//  Unless required by applicable law or agreed to in writing, software

//  distributed under the License is distributed on an "AS IS" BASIS,

//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

//  See the License for the specific language governing permissions and

//  limitations under the License.

//----------------------------------------------------------------------

​

package my_package;

​

class Base;

  // Properties

  rand bit parity_ok;

  rand bit [4:0] a, b, c, i, len;

  rand bit [1:0] aa, bb;

  typedef enum {SMALL, MEDIUM, BIG} size_t;

  rand size_t size;

  rand int test;

  int test_range[] = {1,2,3,5,6,9};

  rand int test1;

  int test1_range[] = {55,44,33,22};

  constraint c1 {a == 4;}

  constraint c2 {b > 3; c > 10;}

  constraint valid_parity {parity_ok dist {0:=1, 1:=9};}

  constraint c3 {size == BIG -> len > 20;}

  constraint c4 {i inside {1,[2:3]};} // Equiv. to i==1 || i==2 || i==3

  constraint c5 {solve b,c before a;}

  constraint c6 {unique{a,b,c};} // (a != b) && (b != c) && (c != a)

  constraint c7 {soft aa[0]==0; soft bb[0]==1;} // lower priority

  constraint c8 {

    test  == get_the_value(test_range);

  }

  constraint c9 {

    test1  == get_the_value(test1_range);

  }

  function int get_the_value(int range[]);

    randcase

      1: get_the_value = 0;

      1: begin

            int i = $urandom_range(0, range.size()-1);

            get_the_value = range[i];

          end

      1: get_the_value = 100;

    endcase

  endfunction

endclass

​

endpackage

​

​

module GRG_constraint;

  import my_package::*;

​

  Base  B_h;

​

initial begin

  B_h = new;

  for (int j = 0; j < 15; j++)

  begin

    if (B_h.randomize() with {soft aa[0]==1; bb[0]==0;}) // higher priority

      //$display("a = %2d, b = %2d, c = %2d, parity_ok = %0d, size = %6s, len = %2d, i = %2d, aa = %b, bb = %b",

       //B_h.a, B_h.b, B_h.c, B_h.parity_ok, B_h.size.name(), B_h.len, B_h.i, B_h.aa, B_h.bb);

      $display("test = %2d, test1 = %2d", B_h.test, B_h.test1);

    else

      $error("Failed to randomize Base");

    #10;

  end

end

​

endmodule

​