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1 files changed, 108 insertions, 0 deletions

diff --git a/tests/div/test.v b/tests/div/test.v
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--- /dev/null
+++ b/tests/div/test.v
@@ -0,0 +1,108 @@
+`default_nettype none
+
+`include "messages.vh"
+
+`ifndef SIMULATION
+ `error_SIMULATION_not_defined
+; /* Cause syntax error */
+`endif
+
+module div_test();
+   reg clock;
+   reg start;
+   reg [15:0] dividend;
+   reg [15:0] divisor;
+
+   wire [15:0] quotient;
+   wire [15:0] remainder;
+   wire        done;
+
+   div
+  #(
+    .WIDTH(16)
+    ) div
+    (
+     .clock(clock),
+     .start(start),
+     .dividend(dividend),
+     .divisor(divisor),
+     .quotient(quotient),
+     .remainder(remainder),
+     .done(done)
+     );
+
+   integer     seed;
+   integer     progress;
+   reg [15:0]  new_divisor;
+   reg [16:0]  max_divisor;
+
+   initial begin
+      seed <= 0;
+      progress <= 0;
+      clock <= 0;
+   end
+
+   // initial
+   //   $monitor("[%t] clock is %b", $time, clock);
+
+   always #1
+     clock <= ~clock;
+
+   always @ (posedge clock) begin
+      if (progress == 0) begin
+	 start <= 1;
+	 dividend <= 15;
+	 divisor <= 3;
+	 progress <= progress + 1;
+      end else begin	 
+	 if (done) begin
+	    if (dividend / divisor === quotient && dividend % divisor === remainder) begin
+	       `DBG(("%0d/%0d computed as %0d r %0d", dividend, divisor, quotient, remainder));
+	    end else begin
+	       `MSG(("error: %0d/%0d computed as %0d r %0d",
+		     dividend, divisor, quotient, remainder));
+	    end
+	    start <= 1;
+	    case (progress)
+	      1 : begin
+		 dividend <= 3;
+		 divisor <= 4;
+	      end
+	      2 : begin
+		 dividend <= 65535;
+		 divisor <= 65534;
+	      end
+	      3 : begin
+		 dividend <= 1024;
+		 divisor <= 4;
+	      end
+	      4 : begin
+		 dividend <= 319;
+		 divisor <= 17;
+	      end
+	      default : begin
+		 if (progress == 500)
+		   $finish;
+		 else if (progress > 400)
+		   max_divisor = 2**16;
+		 else if (progress > 200)
+		   max_divisor = 2**10;
+		 else
+ 		   max_divisor = 2**5;
+
+		 for (new_divisor = $urandom(seed) % max_divisor;
+		      new_divisor == 0;
+		      new_divisor = $urandom(seed) % max_divisor)
+		   ;
+
+		 dividend <= $urandom(seed);
+		 divisor <= new_divisor;
+	      end
+	    endcase // case (progress)
+	    progress <= progress + 1;
+	 end else begin // if (done)
+	    start <= 0;
+	 end // else: !if(done)
+      end // else: !if(progress == 0)
+   end // always @ (posedge clock)
+endmodule // div_test