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feat: add most control flow instructions

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EliseZeroTwo 2021-11-28 16:12:19 +01:00
parent b8cdc65ca7
commit 52098341dd
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GPG key ID: E6D56A6F7B7991DE
6 changed files with 710 additions and 20 deletions
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10
src/gameboy.rs
View file

@ -237,4 +237,14 @@ impl Gameboy {
}
}
}
pub fn cpu_push_stack(&mut self, byte: u8) {
self.registers.sp = self.registers.sp.overflowing_sub(1).0;
self.cpu_write_u8(self.registers.sp, byte)
}
pub fn cpu_pop_stack(&mut self) {
self.cpu_read_u8(self.registers.sp);
self.registers.sp = self.registers.sp.overflowing_add(1).0;
}
}

29
src/gameboy/cpu.rs
View file

@ -1,4 +1,5 @@
mod alu;
mod flow;
mod load_store_move;
mod prefixed;
@ -56,7 +57,7 @@ pub struct Registers {
// Not actual registers
pub cycle: u8,
pub hold: Option<u16>,
pub opcode_len: Option<u8>,
pub opcode_bytecount: Option<u8>,
pub current_opcode: Option<u8>,
pub current_prefixed_opcode: Option<u8>,
pub mem_read_hold: Option<u8>,
@ -122,11 +123,16 @@ pub fn tick_cpu(state: &mut Gameboy) {
0x08 => load_store_move::ld_deref_imm_u16_sp,
0x0a => load_store_move::ld_a_deref_bc,
0x11 => load_store_move::ld_de_imm_u16,
0x18 => flow::jr_i8,
0x1a => load_store_move::ld_a_deref_de,
0x20 => flow::jr_nz_i8,
0x21 => load_store_move::ld_hl_imm_u16,
0x22 => load_store_move::ld_hl_plus_a,
0x28 => flow::jr_z_i8,
0x2a => load_store_move::ld_a_hl_plus,
0x30 => flow::jr_nc_i8,
0x32 => load_store_move::ld_hl_minus_a,
0x38 => flow::jr_c_i8,
0x3a => load_store_move::ld_a_hl_minus,
0x31 => load_store_move::ld_sp_imm_u16,
0x40 => load_store_move::ld_b_b,
@ -201,15 +207,32 @@ pub fn tick_cpu(state: &mut Gameboy) {
0xAD => alu::xor_a_l,
0xAE => alu::xor_a_deref_hl,
0xAF => alu::xor_a_a,
0xC0 => flow::ret_nz,
0xC2 => flow::jp_nz_u16,
0xC3 => flow::jp_u16,
0xC4 => flow::call_nz_u16,
0xC8 => flow::ret_z,
0xC9 => flow::ret,
0xCA => flow::jp_z_u16,
0xCB => prefixed::prefixed_handler,
0xCC => flow::call_z_u16,
0xCD => flow::call_u16,
0xD0 => flow::ret_nc,
0xD2 => flow::jp_nc_u16,
0xD4 => flow::call_nc_u16,
0xD8 => flow::ret_c,
0xD9 => flow::reti,
0xDA => flow::jp_c_u16,
0xDC => flow::call_c_u16,
0xDE => alu::sbc_a_imm_u8,
0xE9 => flow::jp_hl,
0xEE => alu::xor_a_imm_u8,
0xF9 => load_store_move::ld_sp_hl,
unknown => panic!("Unrecognized opcode: {:#X}\nRegisters: {:#?}", unknown, state.registers),
}(state);
if instruction_result == CycleResult::Finished {
match state.registers.opcode_len {
match state.registers.opcode_bytecount {
Some(len) => state.registers.pc += len as u16,
None => panic!("Forgot to set opcode len for {:#X}", opcode),
}
@ -222,7 +245,7 @@ pub fn tick_cpu(state: &mut Gameboy) {
state.registers.cycle = 0;
state.registers.current_prefixed_opcode = None;
state.registers.current_opcode = None;
state.registers.opcode_len = None;
state.registers.opcode_bytecount = None;
log::trace!("Cycle finished");
} else {
state.registers.cycle += 1;

12
src/gameboy/cpu/alu.rs
View file

@ -35,7 +35,7 @@ macro_rules! define_xor_reg {
state.registers.set_subtract(false);
state.registers.set_half_carry(false);
state.registers.set_carry(false);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -58,7 +58,7 @@ macro_rules! define_sbc_reg {
state.registers.set_subtract(true);
state.registers.set_half_carry(half_carry);
state.registers.set_carry(carry);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
},
_ => unreachable!(),
@ -88,7 +88,7 @@ pub fn xor_a_deref_hl(state: &mut Gameboy) -> CycleResult {
state.registers.set_subtract(false);
state.registers.set_half_carry(false);
state.registers.set_carry(false);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -107,7 +107,7 @@ pub fn xor_a_imm_u8(state: &mut Gameboy) -> CycleResult {
state.registers.set_subtract(false);
state.registers.set_half_carry(false);
state.registers.set_carry(false);
state.registers.opcode_len = Some(2);
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
}
_ => unreachable!(),
@ -140,7 +140,7 @@ pub fn sbc_a_deref_hl(state: &mut Gameboy) -> CycleResult {
state.registers.set_subtract(true);
state.registers.set_half_carry(half_carry);
state.registers.set_carry(carry);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -165,7 +165,7 @@ pub fn sbc_a_imm_u8(state: &mut Gameboy) -> CycleResult {
state.registers.set_subtract(true);
state.registers.set_half_carry(half_carry);
state.registers.set_carry(carry);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),

657
src/gameboy/cpu/flow.rs Normal file
View file

@ -0,0 +1,657 @@
use super::CycleResult;
use crate::gameboy::Gameboy;
pub fn jr_nz_i8(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
if state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
2 => {
let relative = state.registers.take_mem();
const TC_BITFLAG: u8 = 1 << 7;
if relative & TC_BITFLAG == 0 {
state.registers.pc = state.registers.pc.overflowing_add(relative as u16).0;
} else {
state.registers.pc =
state.registers.pc.overflowing_sub((relative & !TC_BITFLAG) as u16).0;
}
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jr_nc_i8(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
if state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
2 => {
let relative = state.registers.take_mem();
const TC_BITFLAG: u8 = 1 << 7;
if relative & TC_BITFLAG == 0 {
state.registers.pc = state.registers.pc.overflowing_add(relative as u16).0;
} else {
state.registers.pc =
state.registers.pc.overflowing_sub((relative & !TC_BITFLAG) as u16).0;
}
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jr_z_i8(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
if !state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
2 => {
let relative = state.registers.take_mem();
const TC_BITFLAG: u8 = 1 << 7;
if relative & TC_BITFLAG == 0 {
state.registers.pc = state.registers.pc.overflowing_add(relative as u16).0;
} else {
state.registers.pc =
state.registers.pc.overflowing_sub((relative & !TC_BITFLAG) as u16).0;
}
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jr_c_i8(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
if !state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
2 => {
let relative = state.registers.take_mem();
const TC_BITFLAG: u8 = 1 << 7;
if relative & TC_BITFLAG == 0 {
state.registers.pc = state.registers.pc.overflowing_add(relative as u16).0;
} else {
state.registers.pc =
state.registers.pc.overflowing_sub((relative & !TC_BITFLAG) as u16).0;
}
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jr_i8(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => CycleResult::NeedsMore,
2 => {
let relative = state.registers.take_mem();
const TC_BITFLAG: u8 = 1 << 7;
if relative & TC_BITFLAG == 0 {
state.registers.pc = state.registers.pc.overflowing_add(relative as u16).0;
} else {
state.registers.pc =
state.registers.pc.overflowing_sub((relative & !TC_BITFLAG) as u16).0;
}
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => CycleResult::NeedsMore,
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_hl(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.registers.pc = state.registers.get_hl();
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_nz_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_nc_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_z_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if !state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn jp_c_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if !state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn call_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => CycleResult::NeedsMore,
3 => {
state.cpu_push_stack((state.registers.pc.overflowing_add(3).0 >> 8) as u8);
CycleResult::NeedsMore
}
4 => {
state.cpu_push_stack(state.registers.pc.overflowing_add(3).0 as u8);
CycleResult::NeedsMore
}
5 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn call_nz_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
state.cpu_push_stack((state.registers.pc.overflowing_add(3).0 >> 8) as u8);
CycleResult::NeedsMore
}
4 => {
state.cpu_push_stack(state.registers.pc.overflowing_add(3).0 as u8);
CycleResult::NeedsMore
}
5 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn call_nc_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
state.cpu_push_stack((state.registers.pc.overflowing_add(3).0 >> 8) as u8);
CycleResult::NeedsMore
}
4 => {
state.cpu_push_stack(state.registers.pc.overflowing_add(3).0 as u8);
CycleResult::NeedsMore
}
5 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn call_z_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if !state.registers.get_zero() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
state.cpu_push_stack((state.registers.pc.overflowing_add(3).0 >> 8) as u8);
CycleResult::NeedsMore
}
4 => {
state.cpu_push_stack(state.registers.pc.overflowing_add(3).0 as u8);
CycleResult::NeedsMore
}
5 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn call_c_u16(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_read_u8(state.registers.pc.overflowing_add(1).0);
CycleResult::NeedsMore
}
1 => {
let lower = state.registers.take_mem() as u16;
state.registers.set_hold(lower);
state.cpu_read_u8(state.registers.pc.overflowing_add(2).0);
CycleResult::NeedsMore
}
2 => {
if !state.registers.get_carry() {
state.registers.take_mem();
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
} else {
CycleResult::NeedsMore
}
}
3 => {
state.cpu_push_stack((state.registers.pc.overflowing_add(3).0 >> 8) as u8);
CycleResult::NeedsMore
}
4 => {
state.cpu_push_stack(state.registers.pc.overflowing_add(3).0 as u8);
CycleResult::NeedsMore
}
5 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn ret(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
1 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
2 => CycleResult::NeedsMore,
3 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn reti(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
1 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
2 => CycleResult::NeedsMore,
3 => {
state.interrupts.ime = true;
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn ret_nz(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => CycleResult::NeedsMore,
1 => {
if state.registers.get_zero() {
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
} else {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
}
2 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
3 => CycleResult::NeedsMore,
4 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn ret_nc(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => CycleResult::NeedsMore,
1 => {
if state.registers.get_carry() {
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
} else {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
}
2 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
3 => CycleResult::NeedsMore,
4 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn ret_z(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => CycleResult::NeedsMore,
1 => {
if !state.registers.get_zero() {
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
} else {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
}
2 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
3 => CycleResult::NeedsMore,
4 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}
pub fn ret_c(state: &mut Gameboy) -> CycleResult {
match state.registers.cycle {
0 => CycleResult::NeedsMore,
1 => {
if !state.registers.get_carry() {
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
} else {
state.cpu_pop_stack();
CycleResult::NeedsMore
}
}
2 => {
let lsb = state.registers.take_mem() as u16;
state.registers.set_hold(lsb);
state.cpu_pop_stack();
CycleResult::NeedsMore
}
3 => CycleResult::NeedsMore,
4 => {
let address = (state.registers.take_mem() as u16) << 8 | state.registers.take_hold();
state.registers.pc = address;
state.registers.opcode_bytecount = Some(0);
CycleResult::Finished
}
_ => unreachable!(),
}
}

18
src/gameboy/cpu/load_store_move.rs
View file

@ -22,7 +22,7 @@ macro_rules! define_ld_reg_imm_u16 {
reg &= 0xFF;
reg |= (state.registers.take_mem() as u16) << 8;
state.registers.[<set_ $reg>](reg);
state.registers.opcode_len = Some(3);
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
},
_ => unreachable!(),
@ -47,7 +47,7 @@ pub fn ld_sp_hl(state: &mut Gameboy) -> CycleResult {
1 => {
state.registers.sp &= 0xFF;
state.registers.sp |= (state.registers.h as u16) << 8;
state.registers.opcode_len = Some(3);
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
}
_ => unreachable!(),
@ -75,7 +75,7 @@ pub fn ld_deref_imm_u16_sp(state: &mut Gameboy) -> CycleResult {
3 => {
let addr = state.registers.take_hold().overflowing_add(1).0;
state.cpu_write_u8(addr, (state.registers.sp >> 8) as u8);
state.registers.opcode_len = Some(3);
state.registers.opcode_bytecount = Some(3);
CycleResult::Finished
}
_ => unreachable!(),
@ -90,7 +90,7 @@ macro_rules! define_ld_reg_reg {
0 => {
let res = state.registers.$rreg;
state.registers.$lreg = res;
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
},
_ => unreachable!(),
@ -167,7 +167,7 @@ macro_rules! define_ld_reg_deref {
},
1 => {
state.registers.$lreg = state.registers.take_mem();
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
},
_ => unreachable!(),
@ -196,7 +196,7 @@ pub fn ld_hl_minus_a(state: &mut Gameboy) -> CycleResult {
1 => {
let reg = state.registers.get_hl().overflowing_sub(1).0;
state.registers.set_hl(reg);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -213,7 +213,7 @@ pub fn ld_a_hl_minus(state: &mut Gameboy) -> CycleResult {
state.registers.a = state.registers.take_mem();
let reg = state.registers.get_hl().overflowing_sub(1).0;
state.registers.set_hl(reg);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -229,7 +229,7 @@ pub fn ld_hl_plus_a(state: &mut Gameboy) -> CycleResult {
1 => {
let reg = state.registers.get_hl().overflowing_add(1).0;
state.registers.set_hl(reg);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),
@ -246,7 +246,7 @@ pub fn ld_a_hl_plus(state: &mut Gameboy) -> CycleResult {
state.registers.a = state.registers.take_mem();
let reg = state.registers.get_hl().overflowing_add(1).0;
state.registers.set_hl(reg);
state.registers.opcode_len = Some(1);
state.registers.opcode_bytecount = Some(1);
CycleResult::Finished
}
_ => unreachable!(),

4
src/gameboy/cpu/prefixed.rs
View file

@ -99,7 +99,7 @@ macro_rules! define_bit_reg {
state.registers.set_zero(state.registers.$reg & (1 << $bit) == 0);
state.registers.set_subtract(false);
state.registers.set_half_carry(true);
state.registers.opcode_len = Some(2);
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
}
_ => unreachable!(),
@ -144,7 +144,7 @@ macro_rules! define_bit_deref_hl {
state.registers.set_zero(mem_read & (1 << $bit) == 0);
state.registers.set_subtract(false);
state.registers.set_half_carry(true);
state.registers.opcode_len = Some(2);
state.registers.opcode_bytecount = Some(2);
CycleResult::Finished
}
_ => unreachable!(),