Add experimental 6809 opcode decoder.

Just a pleasant distraction, for now.

Reflection/Dispatcher.hpp

@@ -0,0 +1,39 @@
+//
+//  Dispatcher.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 17/03/2023.
+//  Copyright © 2023 Thomas Harte. All rights reserved.
+//
+
+#ifndef Dispatcher_hpp
+#define Dispatcher_hpp
+
+#include <cstdint>
+
+namespace Reflection {
+
+/*!
+	Calls @c t.dispatch<c>(args...) as efficiently as possible.
+*/
+template <typename TargetT, typename... Args> void dispatch(TargetT &t, uint8_t c, Args &&... args) {
+#define Opt(x)		case x: t.template dispatch<x>(std::forward<Args>(args)...);	break
+#define Opt4(x)		Opt(x + 0x00);		Opt(x + 0x01);		Opt(x + 0x02);		Opt(x + 0x03)
+#define Opt16(x)	Opt4(x + 0x00);		Opt4(x + 0x04);		Opt4(x + 0x08);		Opt4(x + 0x0c)
+#define Opt64(x)	Opt16(x + 0x00);	Opt16(x + 0x10);	Opt16(x + 0x20);	Opt16(x + 0x30)
+#define Opt256(x)	Opt64(x + 0x00);	Opt64(x + 0x40);	Opt64(x + 0x80);	Opt64(x + 0xc0)
+
+	switch(c) {
+		Opt256(0);
+	}
+
+#undef Opt256
+#undef Opt64
+#undef Opt16
+#undef Opt4
+#undef Opt
+}
+
+}
+
+#endif /* Dispatcher_hpp */