This construct allows the declaration of inline constraints at the point where the randomize() class method is called. These additional constraints are of the same constraint types and forms as would otherwise be declared in the randomized class. The inline constraints are applied along with the object constraints. The original constraints in the class definition does not have to be changed.

Syntax

result = class_object_name.randomize([integer mode]) with
constraint_block;

Where

• class_object_name : Is the name of the instantiated object.
• mode : Can be either CHECK or SOLVE. If mode is not specified, the default behavior is that of SOLVE.
• constraint_block : Is an anonymous constraint block, which contains the additional inline constraints to be applied along with the object constraints declared in the class.

  1 class frame_t {
  2   rand bit [7:0] src_addr;
  3   rand bit [7:0] dst_addr;
  4   constraint c {
  5      src_addr <=  127;
  6      dst_addr >=  128;
  7   }
  8   task print() {
  9     integer i =0;
 10     printf("Source      address %3d\n",src_addr);
 11     printf("Destination address %3d\n",dst_addr);
 12   }  
 13 }
 14 
 15 program randomize_with {
 16    frame_t frame = new();
 17    integer i = 0;
 18    printf("-------------------------------\n");
 19    printf("Randomize Value\n");
 20    i = frame.randomize();
 21    frame.print();
 22    printf("-------------------------------\n");
 23    printf("Randomize with Value\n");
 24    i = frame.randomize() with {
 25      src_addr > 100;
 26      dst_addr < 130;
 27      dst_addr > 128;
 28    };
 29    frame.print();
 30    printf("-------------------------------\n");
 31 }

 -------------------------------
 Randomize Value
 Source      address   2
 Destination address 171
 -------------------------------
 Randomize with Value
 Source      address 121
 Destination address 129
 -------------------------------

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Deepak Kumar Tala - All rights reserved

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