1 files changed, 70 insertions, 0 deletions
diff --git a/tests/sva/sva_value_change_sim.sv b/tests/sva/sva_value_change_sim.sv
new file mode 100644
index 000000000..92fe30b23
--- /dev/null
+++ b/tests/sva/sva_value_change_sim.sv
@@ -0,0 +1,70 @@
+module top (
+	input clk
+);
+
+reg [7:0] counter = 0;
+
+reg a = 0;
+reg b = 1;
+reg c;
+reg [2:0] wide_a = 3'b10x;
+reg [2:0] wide_b = 'x;
+
+wire a_fell; assign a_fell = $fell(a, @(posedge clk));
+wire a_rose; assign a_rose = $rose(a, @(posedge clk));
+wire a_stable; assign a_stable = $stable(a, @(posedge clk));
+
+wire b_fell; assign b_fell = $fell(b, @(posedge clk));
+wire b_rose; assign b_rose = $rose(b, @(posedge clk));
+wire b_stable; assign b_stable = $stable(b, @(posedge clk));
+
+wire c_fell; assign c_fell = $fell(c, @(posedge clk));
+wire c_rose; assign c_rose = $rose(c, @(posedge clk));
+wire c_stable; assign c_stable = $stable(c, @(posedge clk));
+
+wire wide_a_stable; assign wide_a_stable = $stable(wide_a, @(posedge clk));
+wire wide_b_stable; assign wide_b_stable = $stable(wide_b, @(posedge clk));
+
+always @(posedge clk) begin
+	counter <= counter + 1;
+
+	case (counter)
+		0: begin
+            assert property ( $fell(a) && !$rose(a) && !$stable(a));
+            assert property (!$fell(b) &&  $rose(b) && !$stable(b));
+            assert property (!$fell(c) && !$rose(c) &&  $stable(c));
+            assert property (!$stable(wide_a));
+            assert property ($stable(wide_b));
+            a <= 1; b <= 1; c <= 1;
+        end
+		1: begin
+            a <= 0; b <= 1; c <= 'x;
+            wide_a <= 3'b101; wide_b <= 3'bxx0;
+        end
+		2: begin
+            assert property ( $fell(a) && !$rose(a) && !$stable(a));
+            assert property (!$fell(b) && !$rose(b) &&  $stable(b));
+            assert property (!$fell(c) && !$rose(c) && !$stable(c));
+            assert property (!$stable(wide_a));
+            assert property (!$stable(wide_b));
+            a <= 0; b <= 0; c <= 0;
+        end
+		3: begin a <= 0; b <= 1; c <= 'x; end
+		4: begin
+            assert property (!$fell(a) && !$rose(a) &&  $stable(a));
+            assert property (!$fell(b) &&  $rose(b) && !$stable(b));
+            assert property (!$fell(c) && !$rose(c) && !$stable(c));
+            assert property ($stable(wide_a));
+            assert property ($stable(wide_b));
+            a <= 'x; b <= 'x; c <= 'x;
+            wide_a <= 'x; wide_b <= 'x;
+        end
+		5: begin
+            a <= 0; b <= 1; c <= 'x;
+            wide_a <= 3'b10x; wide_b <= 'x;
+            counter <= 0;
+        end
+	endcase;
+end
+
+endmodule