ft: implement disasm in own struct

This makes it easier to implement each opcode,
as the offset calculation and recovery of raw
read bytes is internalized.

src/instructions.rs

@@ -6,7 +6,7 @@ pub type b = u8;
 #[allow(non_camel_case_types)]
 pub type w = u16;
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[allow(dead_code)]
 /// A single 'line' of executable ASM is called an Instruction, which
 /// contains the `Opcode` that will be executed, alongside its starting offset
@@ -37,7 +37,7 @@ impl fmt::Display for Instruction {
     }
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[allow(dead_code, non_camel_case_types)]
 pub enum Opcode {
     NOP(),
@@ -61,7 +61,7 @@ impl fmt::Display for Opcode {
 }
 
 /// Registers of a 8086 processor
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[allow(dead_code)]
 pub enum Register {
     AX,
@@ -167,11 +167,11 @@ impl fmt::Display for SegmentRegister {
 }
 
 /// An immediate byte value for an instruction.
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct ImmediateByte(pub b);
 
 /// An immediate word value for an instruction
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct ImmediateWord(pub w);
 
 macro_rules! impl_display_and_lowerhex {
@@ -195,7 +195,7 @@ impl_display_and_lowerhex!(ImmediateWord);
 
 /// A memory index operand is usually created by ModRM bytes or words.
 /// e.g. [bx+si]
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct MemoryIndex {
     pub base: Option<Register>,
     pub index: Option<Register>,
@@ -226,7 +226,7 @@ impl fmt::Display for MemoryIndex {
     }
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[allow(dead_code)]
 /// Displacement for ModRM
 pub enum Displacement {