chore: remove unnecessary derivations from structs

src/apu.rs

@@ -17,7 +17,7 @@ const AUDIO_BUFFER_LEN: usize = 512;
 const CHANNEL_COUNT: usize = 2;
 const SAMPLE_INCREMENT: u64 = SAMPLE_RATE as u64;
 
-#[derive(Default, Debug, Clone)]
+#[derive(Default, Debug)]
 pub struct Apu {
     ctrl: SoundControl,
     /// Tone & Sweep
@@ -349,7 +349,7 @@ impl Apu {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct SoundControl {
     /// 0xFF24 | NR50 - Channel Control
     channel: ChannelControl,
@@ -394,7 +394,7 @@ impl SoundControl {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Channel1 {
     /// 0xFF10 | NR10 - Channel 1 Sweep Register
     sweep: Sweep,
@@ -557,7 +557,7 @@ impl Channel1 {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Channel2 {
     /// 0xFF16 | NR21 - Channel 2 Sound length / Wave Pattern Duty
     duty: SoundDuty,
@@ -660,7 +660,7 @@ impl Channel2 {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Channel3 {
     /// 0xFF1A | NR30 - Channel 3 Sound on/off
     enabled: bool,
@@ -798,7 +798,7 @@ impl Channel3 {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Channel4 {
     /// 0xFF20 | NR41 - Channel 4 Sound Length
     len: u8,

src/apu/gen.rs

@@ -16,7 +16,7 @@ impl AudioMPSC {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct AudioSender<T> {
     inner: Sender<T>,
 }
@@ -64,7 +64,7 @@ impl<T: rodio::Sample> Source for AudioReceiver<T> {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub(crate) struct AudioBuffer<T> {
     inner: VecDeque<T>,
 }

src/bus.rs

@@ -11,7 +11,7 @@ use std::{fs::File, io::Read};
 
 const BOOT_ROM_SIZE: usize = 0x100;
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct Bus {
     boot: Option<[u8; BOOT_ROM_SIZE]>, // Boot ROM is 256b long
     cartridge: Option<Cartridge>,

src/cartridge.rs

@@ -8,7 +8,7 @@ const RAM_SIZE_ADDRESS: usize = 0x0149;
 const ROM_SIZE_ADDRESS: usize = 0x0148;
 const MBC_TYPE_ADDRESS: usize = 0x0147;
 
-#[derive(Debug, Clone, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Cartridge {
     memory: Vec<u8>,
     title: Option<String>,
@@ -144,7 +144,7 @@ impl BusIo for Cartridge {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 struct Mbc1 {
     /// 5-bit number
     rom_bank: u8,
@@ -293,7 +293,7 @@ enum MBC3Device {
     RealTimeClock,
 }
 
-#[derive(Debug, Clone, Default)]
+#[derive(Debug, Default)]
 struct MBC3 {
     /// 7-bit Number
     rom_bank: u8,
@@ -361,7 +361,7 @@ impl MemoryBankController for MBC3 {
     }
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 struct NoMbc {}
 
 impl MemoryBankController for NoMbc {
@@ -374,24 +374,11 @@ impl MemoryBankController for NoMbc {
     }
 }
 
-trait MemoryBankController: CloneMbc {
+trait MemoryBankController {
     fn handle_read(&self, addr: u16) -> MbcResult;
     fn handle_write(&mut self, addr: u16, byte: u8);
 }
 
-trait CloneMbc {
-    fn clone_mbc(&self) -> Box<dyn MemoryBankController>;
-}
-
-impl<T> CloneMbc for T
-where
-    T: MemoryBankController + Clone + 'static,
-{
-    fn clone_mbc<'a>(&self) -> Box<dyn MemoryBankController> {
-        Box::new(self.clone())
-    }
-}
-
 #[derive(Debug, Clone, Copy)]
 enum MbcResult {
     Address(usize),
@@ -485,7 +472,7 @@ impl Default for BankCount {
 
 impl BankCount {
     // https://hacktix.github.io/GBEDG/mbcs/#rom-size
-    fn size(self) -> u32 {
+    fn size(&self) -> u32 {
         use BankCount::*;
 
         match self {
@@ -533,12 +520,6 @@ impl std::fmt::Debug for Box<dyn MemoryBankController> {
     }
 }
 
-impl std::clone::Clone for Box<dyn MemoryBankController> {
-    fn clone(&self) -> Self {
-        self.clone_mbc()
-    }
-}
-
 impl Default for Box<dyn MemoryBankController> {
     fn default() -> Self {
         Box::new(Mbc1::default())

src/cpu.rs

@@ -8,7 +8,7 @@ use crate::timer::Timer;
 use bitfield::bitfield;
 use std::fmt::{Display, Formatter, Result as FmtResult};
 
-#[derive(Debug, Clone, Default)]
+#[derive(Debug, Default)]
 pub struct Cpu {
     pub bus: Bus,
     reg: Registers,
@@ -45,8 +45,8 @@ impl Cpu {
         })
     }
 
-    pub(crate) fn ime(&self) -> ImeState {
+    pub(crate) fn ime(&self) -> &ImeState {
-        self.ime
+        &self.ime
     }
 
     pub(crate) fn set_ime(&mut self, state: ImeState) {
@@ -61,8 +61,8 @@ impl Cpu {
         self.halted = None;
     }
 
-    pub(crate) fn halted(&self) -> Option<HaltState> {
+    pub(crate) fn halted(&self) -> Option<&HaltState> {
-        self.halted
+        self.halted.as_ref()
     }
 
     fn inc_pc(&mut self) {
@@ -267,7 +267,7 @@ impl Cpu {
     }
 }
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Clone, Copy)]
 enum State {
     Execute,
     // Halt,
@@ -400,7 +400,7 @@ impl Cpu {
     }
 }
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Clone, Copy)]
 pub(crate) enum Register {
     A,
     B,
@@ -412,7 +412,7 @@ pub(crate) enum Register {
     Flag,
 }
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Clone, Copy)]
 pub(crate) enum RegisterPair {
     AF,
     BC,
@@ -422,7 +422,7 @@ pub(crate) enum RegisterPair {
     PC,
 }
 
-#[derive(Debug, Copy, Clone, Default)]
+#[derive(Debug, Default)]
 struct Registers {
     a: u8,
     b: u8,

src/instruction.rs

@@ -2,7 +2,7 @@ use crate::bus::BusIo;
 use crate::cpu::{Cpu, Flags, HaltState, ImeState, Register, RegisterPair};
 use std::{convert::TryFrom, fmt::Debug};
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 #[allow(clippy::upper_case_acronyms)]
 pub(crate) enum Instruction {
     NOP,
@@ -51,26 +51,26 @@ pub(crate) enum Instruction {
     SET(u8, InstrRegister),
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum JPTarget {
     RegisterPair(RegisterPair),
     ImmediateWord(u16),
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum Registers {
     Byte(InstrRegister),
     Word(RegisterPair),
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum MATHTarget {
     Register(InstrRegister),
     RegisterPair(RegisterPair),
     ImmediateByte(u8),
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum LDTarget {
     IndirectC,
     Register(InstrRegister),
@@ -82,7 +82,7 @@ pub(crate) enum LDTarget {
     ByteAtAddressWithOffset(u8),
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum InstrRegisterPair {
     AF,
     BC,
@@ -94,7 +94,7 @@ pub(crate) enum InstrRegisterPair {
     DecrementHL,
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum InstrRegister {
     A,
     B,
@@ -106,7 +106,7 @@ pub(crate) enum InstrRegister {
     IndirectHL, // (HL)
 }
 
-#[derive(Copy, Clone)]
+#[derive(Clone, Copy)]
 pub(crate) enum JumpCondition {
     NotZero,
     Zero,
@@ -115,7 +115,7 @@ pub(crate) enum JumpCondition {
     Always,
 }
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug)]
 struct Table;
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Default)]

src/interrupt.rs

@@ -1,6 +1,6 @@
 use bitfield::bitfield;
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Interrupt {
     pub(crate) flag: InterruptFlag,
     pub(crate) enable: InterruptEnable,

src/joypad.rs

@@ -1,7 +1,7 @@
 use gilrs::{Button, Event as GamepadEvent, EventType as GamepadEventType};
 use winit_input_helper::WinitInputHelper;
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 pub struct Joypad {
     /// 0xFF00 | P1/JOYP - Player 1 Joypad
     pub(crate) p1: u8,
@@ -48,7 +48,7 @@ impl Joypad {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct JoypadState {
     // Direction Row
     dpad_down: ButtonEvent,

src/ppu.rs

@@ -33,7 +33,7 @@ const LIGHT_GRAY: [u8; 4] = 0xAEBA89FFu32.to_be_bytes();
 const DARK_GRAY: [u8; 4] = 0x5E6745FFu32.to_be_bytes();
 const BLACK: [u8; 4] = 0x202020FFu32.to_be_bytes();
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct Ppu {
     pub(crate) int: Interrupt,
     /// 0xFF40 | LCDC - LCD Control
@@ -489,7 +489,7 @@ impl Default for Ppu {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Interrupt {
     _vblank: bool,
     _lcd_stat: bool,
@@ -513,7 +513,7 @@ impl Interrupt {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct ScreenPosition {
     /// 0xFF42 | SCY - Scroll Y
     pub(crate) scroll_y: u8,
@@ -529,7 +529,7 @@ pub(crate) struct ScreenPosition {
     pub(crate) window_x: u8,
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Monochrome {
     /// 0xFF47 | BGP - Background Palette Data
     pub(crate) bg_palette: BackgroundPalette,
@@ -539,7 +539,7 @@ pub(crate) struct Monochrome {
     pub(crate) obj_palette_1: ObjectPalette,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub(crate) struct ObjectAttributeTable {
     buf: Box<[u8; OAM_SIZE]>,
 }
@@ -606,7 +606,7 @@ impl<'a> From<&'a [u8; 4]> for ObjectAttribute {
     }
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 struct ObjectBuffer {
     buf: [Option<ObjectAttribute>; OBJECT_LIMIT],
     len: usize,
@@ -674,7 +674,7 @@ impl Default for ObjectBuffer {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct PixelFetcher {
     x_pos: u8,
     back: BackgroundFetcher,
@@ -793,7 +793,7 @@ trait Fetcher {
     fn hblank_reset(&mut self);
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 struct BackgroundFetcher {
     state: FetcherState,
     tile: TileBuilder,
@@ -859,7 +859,7 @@ impl Default for BackgroundFetcher {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct ObjectFetcher {
     state: FetcherState,
     tile: TileBuilder,
@@ -881,7 +881,7 @@ impl Fetcher for ObjectFetcher {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct WindowLineCounter {
     count: u8,
 }
@@ -918,12 +918,12 @@ impl Default for FetcherState {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct BgPixelProperty {
     shade_id: u8,
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct ObjPixelProperty {
     shade_id: u8,
     palette_kind: ObjectPaletteKind,
@@ -932,7 +932,7 @@ struct ObjPixelProperty {
 
 // FIXME: Fifo Registers have a known size. Are heap allocations
 // really necessary here?
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 struct PixelFifo {
     back: VecDeque<BgPixelProperty>,
     obj: VecDeque<ObjPixelProperty>,
@@ -963,7 +963,7 @@ impl Default for PixelFifo {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct TileBuilder {
     id: Option<u8>,
     low: Option<u8>,
@@ -988,7 +988,7 @@ impl TileBuilder {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct OamScanState {
     count: u8,
     mode: OamScanMode,
@@ -1009,8 +1009,8 @@ impl OamScanState {
         self.count
     }
 
-    fn mode(&self) -> OamScanMode {
+    fn mode(&self) -> &OamScanMode {
-        self.mode
+        &self.mode
     }
 
     fn next(&mut self) {
@@ -1035,7 +1035,7 @@ impl Default for OamScanMode {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 struct WindowStatus {
     /// This will be true if WY == LY at any point in the frame thus far
     coincidence: bool,

src/ppu/dma.rs

@@ -1,6 +1,6 @@
 use crate::instruction::Cycle;
 
-#[derive(Debug, Default, Clone)]
+#[derive(Debug, Default)]
 pub(crate) struct DirectMemoryAccess {
     pub(crate) state: DmaState,
     cycle: Cycle,
@@ -28,7 +28,7 @@ impl DirectMemoryAccess {
 
                 let src_addr = self
                     .start
-                    .addr
+                    .0
                     .as_mut()
                     .expect("Source Address present during DMA Transfer");
 
@@ -58,7 +58,7 @@ impl DirectMemoryAccess {
     fn reset(&mut self) {
         self.cycle = Cycle::new(0);
         self.state = DmaState::Disabled;
-        self.start.addr = None;
+        self.start.0 = None;
     }
 }
 
@@ -75,26 +75,21 @@ impl Default for DmaState {
     }
 }
 
-#[derive(Debug, Default, Clone, Copy)]
+#[derive(Debug, Clone, Copy, Default)]
-pub(crate) struct DmaAddress {
+pub(crate) struct DmaAddress(Option<u16>);
-    /// The current *source* address of the DMA Transfer
-    ///
-    /// NB: Will be None if no DMA Transfer is in progress
-    addr: Option<u16>,
-}
 
 impl DmaAddress {
     pub(crate) fn update(&mut self, byte: u8, state: &mut DmaState) {
         let start = (byte as u16) << 8;
 
-        self.addr = Some(start);
+        self.0 = Some(start);
         *state = DmaState::Pending;
     }
 }
 
 impl From<DmaAddress> for u8 {
     fn from(ctrl: DmaAddress) -> Self {
-        match ctrl.addr {
+        match ctrl.0 {
             Some(addr) => (addr >> 8) as u8,
             None => 0xFF, // TODO: What garbage value should be here?
         }

src/serial.rs

@@ -1,6 +1,6 @@
 use bitfield::bitfield;
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Default)]
 pub(crate) struct Serial {
     /// 0xFF01 | SB - Serial Transfer Data
     pub(crate) next: u8,

src/timer.rs

@@ -1,6 +1,6 @@
 use bitfield::bitfield;
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 pub(crate) struct Timer {
     /// 0xFF07 | TAC - Timer Control
     pub(crate) ctrl: TimerControl,

src/work_ram.rs

@@ -5,7 +5,7 @@ const VARIABLE_WORK_RAM_SIZE: usize = WORK_RAM_SIZE;
 const WORK_RAM_START_ADDRESS: usize = 0xC000;
 const VARIABLE_WORK_RAM_START_ADDRESS: usize = 0xD000;
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub(crate) struct WorkRam {
     bank: Box<[u8; WORK_RAM_SIZE]>,
 }
@@ -39,7 +39,7 @@ enum BankNumber {
     Seven = 7,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub(crate) struct VariableWorkRam {
     current: BankNumber,
     bank_n: Box<[[u8; VARIABLE_WORK_RAM_SIZE]; 7]>, // 4K for Variable amount of Banks (Banks 1 -> 7) in Game Boy Colour
@@ -59,8 +59,8 @@ impl VariableWorkRam {
         self.current = bank;
     }
 
-    fn get_current_bank(&self) -> BankNumber {
+    fn get_current_bank(&self) -> &BankNumber {
-        self.current
+        &self.current
     }
 }