Fix generate scoping issues

- expand_genblock defers prefixing of items within named sub-blocks
- Allow partially-qualified references to local scopes
- Handle shadowing within generate blocks
- Resolve generate scope references within tasks and functions
- Apply generate scoping to genvars
- Resolves #2214, resolves #1456

tests/simple/generate.v

@@ -159,3 +159,88 @@ generate
     end
 endgenerate
 endmodule
+
+// ------------------------------------------
+
+module gen_test7;
+	reg [2:0] out1;
+	reg [2:0] out2;
+	wire [2:0] out3;
+	generate
+		begin : cond
+			reg [2:0] sub_out1;
+			reg [2:0] sub_out2;
+			wire [2:0] sub_out3;
+			initial begin : init
+				reg signed [31:0] x;
+				x = 2 ** 2;
+				out1 = x;
+				sub_out1 = x;
+			end
+			always @* begin : proc
+				reg signed [31:0] x;
+				x = 2 ** 1;
+				out2 = x;
+				sub_out2 = x;
+			end
+			genvar x;
+			for (x = 0; x < 3; x = x + 1) begin
+				assign out3[x] = 1;
+				assign sub_out3[x] = 1;
+			end
+		end
+	endgenerate
+
+// `define VERIFY
+`ifdef VERIFY
+	assert property (out1 == 4);
+	assert property (out2 == 2);
+	assert property (out3 == 7);
+	assert property (cond.sub_out1 == 4);
+	assert property (cond.sub_out2 == 2);
+	assert property (cond.sub_out3 == 7);
+`endif
+endmodule
+
+// ------------------------------------------
+
+module gen_test8;
+
+// `define VERIFY
+`ifdef VERIFY
+	`define ASSERT(expr) assert property (expr);
+`else
+	`define ASSERT(expr)
+`endif
+
+	wire [1:0] x = 2'b11;
+	generate
+		begin : A
+			wire [1:0] x;
+			begin : B
+				wire [1:0] x = 2'b00;
+				`ASSERT(x == 0)
+				`ASSERT(A.x == 2)
+				`ASSERT(A.C.x == 1)
+				`ASSERT(A.B.x == 0)
+			end
+			begin : C
+				wire [1:0] x = 2'b01;
+				`ASSERT(x == 1)
+				`ASSERT(A.x == 2)
+				`ASSERT(A.C.x == 1)
+				`ASSERT(A.B.x == 0)
+			end
+			assign x = B.x ^ 2'b11 ^ C.x;
+			`ASSERT(x == 2)
+			`ASSERT(A.x == 2)
+			`ASSERT(A.C.x == 1)
+			`ASSERT(A.B.x == 0)
+		end
+	endgenerate
+
+	`ASSERT(x == 3)
+	`ASSERT(A.x == 2)
+	`ASSERT(A.C.x == 1)
+	`ASSERT(A.B.x == 0)
+endmodule