Merge pull request #3314 from jix/sva_value_change_logic_wide

verific: Use new value change logic also for $stable of wide signals.

2 files changed, 43 insertions, 2 deletions

diff --git a/tests/sva/sva_value_change_changed_wide.sv b/tests/sva/sva_value_change_changed_wide.sv
new file mode 100644
index 000000000..c9147c4f3
--- /dev/null
+++ b/tests/sva/sva_value_change_changed_wide.sv
@@ -0,0 +1,22 @@
+module top (
+	input clk,
+	input [2:0] a,
+	input [2:0] b
+);
+	default clocking @(posedge clk); endclocking
+
+	assert property (
+		$changed(a)
+	);
+
+    assert property (
+        $changed(b) == ($changed(b[0]) || $changed(b[1]) || $changed(b[2]))
+    );
+
+`ifndef FAIL
+	assume property (
+		a !== 'x ##1 $changed(a)
+	);
+`endif
+
+endmodule
diff --git a/tests/sva/sva_value_change_sim.sv b/tests/sva/sva_value_change_sim.sv
index 80ff309cd..92fe30b23 100644
--- a/tests/sva/sva_value_change_sim.sv
+++ b/tests/sva/sva_value_change_sim.sv
@@ -7,6 +7,8 @@ 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));
@@ -20,6 +22,9 @@ 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;
 
@@ -28,13 +33,20 @@ always @(posedge clk) 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; 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
@@ -42,9 +54,16 @@ always @(posedge clk) 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
-		5: begin a <= 0; b <= 1; c <= 'x; counter <= 0; end
 	endcase;
 end