Added $lcu cell type

techlibs/common/simlib.v

@@ -459,6 +459,29 @@ endmodule
 
 // --------------------------------------------------------
 
+module \$lcu (P, G, CI, CO);
+
+parameter WIDTH = 1;
+
+input [WIDTH-1:0] P, G;
+input CI;
+
+output reg [WIDTH-1:0] CO;
+
+integer i;
+always @* begin
+	CO = 'bx;
+	if (^{P, G, CI} !== 1'bx) begin
+		CO[0] = G[0] || (P[0] && CI);
+		for (i = 1; i < WIDTH; i = i+1)
+			CO[i] = G[i] || (P[i] && CO[i-1]);
+	end
+end
+
+endmodule
+
+// --------------------------------------------------------
+
 module \$alu (A, B, CI, BI, X, Y, CO);
 
 parameter A_SIGNED = 0;