Tests: Fix randomize_method test (#4024)

test_regress/t/t_randomize_method.v

@@ -4,6 +4,20 @@
 // any use, without warranty, 2020 by Wilson Snyder.
 // SPDX-License-Identifier: CC0-1.0
 
+`define check_rand(cl, field) \
+begin \
+   longint prev_result; \
+   int ok = 0; \
+   for (int i = 0; i < 10; i++) begin \
+      longint result; \
+      void'(cl.randomize()); \
+      result = longint'(field); \
+      if (i > 0 && result != prev_result) ok = 1; \
+      prev_result = result; \
+   end \
+   if (ok != 1) $stop; \
+end
+
 typedef enum bit[15:0] {
    ONE   = 3,
    TWO   = 5,
@@ -83,12 +97,6 @@ class ContainsNull;
 endclass
 
 module t (/*AUTOARG*/);
-   bit ok = 0;
-   longint checksum;
-
-   task checksum_next(longint x);
-      checksum = x ^ {checksum[62:0],checksum[63]^checksum[2]^checksum[0]};
-   endtask;
 
    DerivedCls derived;
    OtherCls other;
@@ -97,12 +105,11 @@ module t (/*AUTOARG*/);
 
    initial begin
       int rand_result;
-      longint prev_checksum;
+      derived = new;
+      other = new;
+      cont = new;
+      base = derived;
       for (int i = 0; i < 10; i++) begin
-         derived = new;
-         other = new;
-         cont = new;
-         base = derived;
          rand_result = base.randomize();
          rand_result = other.randomize();
          rand_result = cont.randomize();
@@ -113,32 +120,24 @@ module t (/*AUTOARG*/);
          if (derived.k != 0) $stop;
          if (other.v != 0) $stop;
          if (cont.b != null) $stop;
-         checksum = 0;
-         checksum_next(longint'(derived.i.a));
-         checksum_next(longint'(derived.i.b));
-         checksum_next(longint'(derived.i.c));
-         checksum_next(longint'(derived.j));
-         checksum_next(longint'(derived.l));
-         checksum_next(longint'(other.w));
-         checksum_next(longint'(other.x));
-         checksum_next(longint'(other.y));
-         checksum_next(longint'(other.z));
-         checksum_next(longint'(other.str.x));
-         checksum_next(longint'(other.str.y));
-         checksum_next(longint'(other.str.z));
-         checksum_next(longint'(other.str.s.a));
-         checksum_next(longint'(other.str.s.b));
-         checksum_next(longint'(other.str.s.c));
-         $write("checksum: %d\n", checksum);
-         if (i > 0 && checksum != prev_checksum) begin
-            ok = 1;
-         end
-         prev_checksum = checksum;
       end
-      if (ok) begin
+      `check_rand(derived, derived.i.a);
-         $write("*-* All Finished *-*\n");
+      `check_rand(derived, derived.i.b);
-         $finish;
+      `check_rand(derived, derived.i.c);
-      end
+      `check_rand(derived, derived.j);
-      else $stop;
+      `check_rand(derived, derived.l);
+      `check_rand(other, other.w);
+      `check_rand(other, other.x);
+      `check_rand(other, other.y);
+      `check_rand(other, other.z);
+      `check_rand(other, other.str.x);
+      `check_rand(other, other.str.y);
+      `check_rand(other, other.str.z);
+      `check_rand(other, other.str.s.a);
+      `check_rand(other, other.str.s.b);
+      `check_rand(other, other.str.s.c);
+
+      $write("*-* All Finished *-*\n");
+      $finish;
    end
 endmodule