--- /dev/null
+module top;
+ wire [7:0] a, b, c, d;
+ assign a = 8'd16;
+ assign b = 8'd16;
+ assign c = (a * b) >> 8;
+ assign d = (16'(a) * b) >> 8;
+
+ parameter P = 16;
+
+ wire signed [7:0] s0, s1, s2;
+ wire [7:0] u0, u1, u2, u3, u4, u5, u6;
+ assign s0 = -8'd1;
+ assign s1 = 4'(s0);
+ assign s2 = 4'(unsigned'(s0));
+ assign u0 = -8'd1;
+ assign u1 = 4'(u0);
+ assign u2 = 4'(signed'(u0));
+ assign u3 = 8'(4'(s0));
+ assign u4 = 8'(4'(u0));
+ assign u5 = 8'(4'(signed'(-8'd1)));
+ assign u6 = 8'(4'(unsigned'(-8'd1)));
+
+ wire [8:0] n0, n1, n2, n3, n4, n5, n6, n7, n8, n9;
+ assign n0 = s1;
+ assign n1 = s2;
+ assign n2 = 9'(s1);
+ assign n3 = 9'(s2);
+ assign n4 = 9'(unsigned'(s1));
+ assign n5 = 9'(unsigned'(s2));
+ assign n6 = 9'(u0);
+ assign n7 = 9'(u1);
+ assign n8 = 9'(signed'(u0));
+ assign n9 = 9'(signed'(u1));
+
+ always_comb begin
+ assert(c == 8'b0000_0000);
+ assert(d == 8'b0000_0001);
+
+ assert((P + 1)'(a) == 17'b0_0000_0000_0001_0000);
+ assert((P + 1)'(d - 2) == 17'b1_1111_1111_1111_1111);
+
+ assert(s0 == 8'b1111_1111);
+ assert(s1 == 8'b1111_1111);
+ assert(s2 == 8'b0000_1111);
+ assert(u0 == 8'b1111_1111);
+ assert(u1 == 8'b0000_1111);
+ assert(u2 == 8'b1111_1111);
+ assert(u3 == 8'b1111_1111);
+ assert(u4 == 8'b0000_1111);
+ assert(u5 == 8'b1111_1111);
+ assert(u6 == 8'b0000_1111);
+
+ assert(n0 == 9'b1_1111_1111);
+ assert(n1 == 9'b0_0000_1111);
+ assert(n2 == 9'b1_1111_1111);
+ assert(n3 == 9'b0_0000_1111);
+ assert(n4 == 9'b0_1111_1111);
+ assert(n5 == 9'b0_0000_1111);
+ assert(n6 == 9'b0_1111_1111);
+ assert(n7 == 9'b0_0000_1111);
+ assert(n8 == 9'b1_1111_1111);
+ assert(n9 == 9'b0_0000_1111);
+ end
+endmodule