gb-emu/lib/src/processor/instructions/instructions.rs
2023-03-19 11:33:53 +11:00

152 lines
4.3 KiB
Rust

use crate::{
connect::{PocketCamera, Renderer},
processor::{memory::mmio::gpu::Colour, Cpu, Direction, Flags, Reg8, SplitRegister},
util::{clear_bit, get_bit, set_bit},
};
impl<ColourFormat, R, C> Cpu<ColourFormat, R, C>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
C: PocketCamera + Send + 'static,
{
pub(crate) fn and(&mut self, first: u8, second: u8) -> u8 {
let result = first & second;
self.set_or_clear_flag(Flags::Zero, result == 0x0);
self.clear_flag(Flags::NSubtract);
self.clear_flag(Flags::Carry);
self.set_flag(Flags::HalfCarry);
result
}
pub(crate) fn xor(&mut self, first: u8, second: u8) -> u8 {
let result = first ^ second;
self.set_or_clear_flag(Flags::Zero, result == 0x0);
self.clear_flag(Flags::NSubtract);
self.clear_flag(Flags::Carry);
self.clear_flag(Flags::HalfCarry);
result
}
pub(crate) fn or(&mut self, first: u8, second: u8) -> u8 {
let result = first | second;
self.set_or_clear_flag(Flags::Zero, result == 0x0);
self.clear_flag(Flags::NSubtract);
self.clear_flag(Flags::Carry);
self.clear_flag(Flags::HalfCarry);
result
}
pub(crate) fn cp(&mut self, first: u8, second: u8) {
self.sub_u8s(first, second, false);
}
pub(crate) fn add(&mut self, first: u8, second: u8) -> u8 {
self.add_u8s(first, second, false)
}
pub(crate) fn adc(&mut self, first: u8, second: u8) -> u8 {
let carry = self.is_flag(Flags::Carry);
self.clear_flag(Flags::Carry);
self.add_u8s(first, second, carry)
}
pub(crate) fn sub(&mut self, first: u8, second: u8) -> u8 {
self.sub_u8s(first, second, false)
}
pub(crate) fn sbc(&mut self, first: u8, second: u8) -> u8 {
self.sub_u8s(first, second, self.is_flag(Flags::Carry))
}
pub(crate) fn inc(&mut self, reg: Reg8) {
let result = self.reg.get_8(reg);
let val = self.inc_raw(result);
self.reg.set_8(reg, val);
}
pub(crate) fn dec(&mut self, reg: Reg8) {
let result = self.reg.get_8(reg);
let val = self.dec_flags(result);
self.reg.set_8(reg, val);
}
pub(crate) fn inc_pair(&mut self, val: u16) -> u16 {
val.wrapping_add(0x1)
}
pub(crate) fn dec_pair(&mut self, val: u16) -> u16 {
val.wrapping_sub(0x1)
}
pub(crate) fn rlc(&mut self, byte: u8) -> u8 {
self.rotate_with_carry(byte, Direction::Left)
}
pub(crate) fn rrc(&mut self, byte: u8) -> u8 {
self.rotate_with_carry(byte, Direction::Right)
}
pub(crate) fn rl(&mut self, byte: u8) -> u8 {
self.rotate(byte, Direction::Left)
}
pub(crate) fn rr(&mut self, byte: u8) -> u8 {
self.rotate(byte, Direction::Right)
}
pub(crate) fn sla(&mut self, byte: u8) -> u8 {
self.shift(byte, Direction::Left)
}
pub(crate) fn sra(&mut self, byte: u8) -> u8 {
let b = get_bit(byte, 7);
let val = self.shift(byte, Direction::Right);
if b {
val + 0b10000000
} else {
val
}
}
pub(crate) fn srl(&mut self, byte: u8) -> u8 {
self.shift(byte, Direction::Right)
}
pub(crate) fn swap(&mut self, byte: u8) -> u8 {
let swapped = (byte & 0x0F) << 4 | (byte & 0xF0) >> 4;
self.set_or_clear_flag(Flags::Zero, swapped == 0x0);
self.clear_flag(Flags::Carry);
self.clear_flag(Flags::HalfCarry);
self.clear_flag(Flags::NSubtract);
swapped
}
pub(crate) fn bit(&mut self, byte: u8, bit: u8) {
self.set_or_clear_flag(Flags::Zero, !get_bit(byte, bit));
self.clear_flag(Flags::NSubtract);
self.set_flag(Flags::HalfCarry);
}
pub(crate) fn rst(&mut self, address: u8) {
self.push(self.reg.pc);
self.reg.pc.set_high(0x0);
self.reg.pc.set_low(address);
}
pub(crate) fn ret(&mut self) {
self.reg.pc = self.pop_word();
}
pub(crate) fn jr(&mut self, jump: i8) {
self.reg.pc = self.reg.pc.wrapping_add_signed(jump.into());
}
}
pub(crate) fn res(byte: u8, bit: u8) -> u8 {
clear_bit(byte, bit)
}
pub(crate) fn set(byte: u8, bit: u8) -> u8 {
set_bit(byte, bit)
}