Added colbufs test case

icefuzz/tests/colbufs.pcf

@@ -0,0 +1,8 @@
+set_io clk[0] J3
+set_io clk[1] G1
+set_io clk[2] R9
+set_io clk[3] F7
+set_io clk[4] K9
+set_io clk[5] C8
+set_io clk[6] H11
+set_io clk[7] H16

icefuzz/tests/colbufs.v

@@ -0,0 +1,34 @@
+module top #(
+	parameter NUM_BITS = 8
+) (
+	input [NUM_BITS-1:0] clk,
+	output reg [NUM_BITS-1:0] y
+);
+	wire [NUM_BITS-1:0] t1;
+	reg [NUM_BITS-1:0] t2;
+
+	genvar i;
+	generate for (i = 0; i < NUM_BITS; i = i+1) begin:bitslice
+		SB_RAM40_4K #(
+			.READ_MODE(0),
+			.WRITE_MODE(0)
+		) ram40 (
+			.WADDR(8'b0),
+			.RADDR(8'b0),
+			.MASK(~16'b0),
+			.WDATA(8'b0),
+			.RDATA(t1[i]),
+			.WE(1'b1),
+			.WCLKE(1'b1),
+			.WCLK(clk[i]),
+			.RE(1'b1),
+			.RCLKE(1'b1),
+			.RCLK(clk[i])
+		);
+
+		always @(posedge clk[i]) begin
+			t2[i] <= t1[i];
+			y[i] <= t2[i];
+		end
+	end endgenerate
+endmodule