mirror of
https://github.com/FranLMSP/snes.git
synced 2026-10-03 07:55:17 -04:00
some branch instructions
This commit is contained in:
@@ -1,6 +1,5 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::cycles;
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use super::{CPUInstruction, Decode};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::decoder_common;
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use super::branch_common;
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use super::branch_common;
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@@ -11,14 +10,7 @@ pub struct BCC {}
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impl CPUInstruction for BCC {
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impl CPUInstruction for BCC {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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branch_common::do_branch_instr(registers, bus, !registers.get_carry_flag());
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let (bytes, cycles) = cycles::increment_cycles_branch();
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registers.increment_pc(bytes); registers.cycles += cycles;
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if !registers.get_carry_flag() {
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let page_boundary_crossed = branch_common::do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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registers.increment_pc(bytes); registers.cycles += cycles;
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}
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}
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}
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}
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}
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@@ -34,7 +26,7 @@ mod cpu_instructions_tests {
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use super::*;
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use super::*;
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#[test]
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#[test]
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fn test_bcc() {
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fn test() {
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let instruction = BCC{};
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let instruction = BCC{};
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// test with positive nearlabel
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// test with positive nearlabel
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// branch not taken
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// branch not taken
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@@ -1,6 +1,5 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::cycles;
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use super::{CPUInstruction, Decode};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::decoder_common;
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use super::branch_common;
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use super::branch_common;
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@@ -11,14 +10,7 @@ pub struct BCS {}
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impl CPUInstruction for BCS {
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impl CPUInstruction for BCS {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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branch_common::do_branch_instr(registers, bus, registers.get_carry_flag());
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let (bytes, cycles) = cycles::increment_cycles_branch();
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registers.increment_pc(bytes); registers.cycles += cycles;
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if registers.get_carry_flag() {
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let page_boundary_crossed = branch_common::do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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registers.increment_pc(bytes); registers.cycles += cycles;
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}
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}
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}
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}
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}
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@@ -34,7 +26,7 @@ mod cpu_instructions_tests {
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use super::*;
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use super::*;
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#[test]
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#[test]
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fn test_bcs() {
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fn test() {
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let instruction = BCS{};
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let instruction = BCS{};
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// test with positive nearlabel
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// test with positive nearlabel
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// branch not taken
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// branch not taken
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@@ -1,6 +1,5 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::cycles;
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use super::{CPUInstruction, Decode};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::decoder_common;
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use super::branch_common;
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use super::branch_common;
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@@ -11,14 +10,7 @@ pub struct BEQ {}
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impl CPUInstruction for BEQ {
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impl CPUInstruction for BEQ {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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branch_common::do_branch_instr(registers, bus, registers.get_zero_flag());
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let (bytes, cycles) = cycles::increment_cycles_branch();
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registers.increment_pc(bytes); registers.cycles += cycles;
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if registers.get_zero_flag() {
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let page_boundary_crossed = branch_common::do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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registers.increment_pc(bytes); registers.cycles += cycles;
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}
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}
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}
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}
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}
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@@ -34,7 +26,7 @@ mod cpu_instructions_tests {
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use super::*;
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use super::*;
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#[test]
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#[test]
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fn test_beq() {
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fn test() {
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let instruction = BEQ{};
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let instruction = BEQ{};
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// test with positive nearlabel
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// test with positive nearlabel
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// branch not taken
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// branch not taken
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@@ -0,0 +1,59 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::branch_common;
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static INSTR_NAME: &'static str = "BMI";
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pub struct BMI {}
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impl CPUInstruction for BMI {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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branch_common::do_branch_instr(registers, bus, registers.get_negative_flag());
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}
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}
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impl Decode for BMI {
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fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
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decoder_common::mnemonic_branch_nearlabel(opcode, INSTR_NAME, registers, bus)
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}
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}
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#[cfg(test)]
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mod cpu_instructions_tests {
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use super::*;
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#[test]
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fn test() {
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let instruction = BMI{};
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// test with positive nearlabel
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// branch not taken
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let mut registers = Registers::new();
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let mut bus = Bus::new();
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registers.pc = 0x0000;
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registers.cycles = 0;
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registers.set_negative_flag(false);
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bus.write(0x02, 0b00001111);
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0x02);
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assert_eq!(registers.cycles, 2);
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// branch taken
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registers.pc = 0x0000;
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registers.cycles = 0;
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registers.set_negative_flag(true);
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bus.write(0x01, 0b00001111);
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0x02 + 0b00001111);
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assert_eq!(registers.cycles, 3);
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// test with negative nearlabel and boundary cross
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registers.pc = 0x0100;
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registers.cycles = 0;
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registers.set_negative_flag(true);
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bus.write(0x101, 0xFB); // write -5
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0xFD);
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assert_eq!(registers.cycles, 4);
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}
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}
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@@ -1,6 +1,5 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::{bus::Bus, registers::Registers};
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use crate::cpu::cycles;
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use super::{CPUInstruction, Decode};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::decoder_common;
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use super::branch_common;
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use super::branch_common;
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@@ -11,14 +10,7 @@ pub struct BNE {}
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impl CPUInstruction for BNE {
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impl CPUInstruction for BNE {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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branch_common::do_branch_instr(registers, bus, !registers.get_zero_flag());
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let (bytes, cycles) = cycles::increment_cycles_branch();
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registers.increment_pc(bytes); registers.cycles += cycles;
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if !registers.get_zero_flag() {
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let page_boundary_crossed = branch_common::do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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registers.increment_pc(bytes); registers.cycles += cycles;
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}
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}
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}
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}
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}
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@@ -34,7 +26,7 @@ mod cpu_instructions_tests {
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use super::*;
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use super::*;
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#[test]
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#[test]
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fn test_beq() {
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fn test() {
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let instruction = BNE{};
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let instruction = BNE{};
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// test with positive nearlabel
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// test with positive nearlabel
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// branch not taken
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// branch not taken
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@@ -0,0 +1,59 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::branch_common;
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static INSTR_NAME: &'static str = "BPL";
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pub struct BPL {}
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impl CPUInstruction for BPL {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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branch_common::do_branch_instr(registers, bus, !registers.get_negative_flag());
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}
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}
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impl Decode for BPL {
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fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
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decoder_common::mnemonic_branch_nearlabel(opcode, INSTR_NAME, registers, bus)
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}
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}
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#[cfg(test)]
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mod cpu_instructions_tests {
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use super::*;
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#[test]
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fn test() {
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let instruction = BPL{};
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// test with positive nearlabel
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// branch not taken
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let mut registers = Registers::new();
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let mut bus = Bus::new();
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registers.pc = 0x0000;
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registers.cycles = 0;
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registers.set_negative_flag(true);
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bus.write(0x02, 0b00001111);
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0x02);
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assert_eq!(registers.cycles, 2);
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// branch taken
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registers.pc = 0x0000;
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registers.cycles = 0;
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registers.set_negative_flag(false);
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bus.write(0x01, 0b00001111);
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0x02 + 0b00001111);
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assert_eq!(registers.cycles, 3);
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// test with negative nearlabel and boundary cross
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registers.pc = 0x0100;
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registers.cycles = 0;
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registers.set_negative_flag(false);
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bus.write(0x101, 0xFB); // write -5
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0xFD);
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assert_eq!(registers.cycles, 4);
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}
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}
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@@ -0,0 +1,55 @@
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use crate::cpu::{bus::Bus, registers::Registers};
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use super::{CPUInstruction, Decode};
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use super::decoder_common;
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use super::branch_common;
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use crate::cpu::cycles;
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static INSTR_NAME: &'static str = "BRA";
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pub struct BRA {}
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impl CPUInstruction for BRA {
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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let (bytes, cycles) = cycles::increment_cycles_branch();
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registers.increment_pc(bytes); registers.cycles += cycles;
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let page_boundary_crossed = branch_common::do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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registers.increment_pc(bytes); registers.cycles += cycles;
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}
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}
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impl Decode for BRA {
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fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
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decoder_common::mnemonic_branch_nearlabel(opcode, INSTR_NAME, registers, bus)
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}
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}
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#[cfg(test)]
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mod cpu_instructions_tests {
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use super::*;
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|
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#[test]
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fn test() {
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let instruction = BRA{};
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// test with positive nearlabel
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// branch always taken
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let mut registers = Registers::new();
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let mut bus = Bus::new();
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registers.pc = 0x0000;
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registers.cycles = 0;
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bus.write(0x01, 0b00001111);
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0x02 + 0b00001111);
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assert_eq!(registers.cycles, 3);
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// test with negative nearlabel and boundary cross
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registers.pc = 0x0100;
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registers.cycles = 0;
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bus.write(0x101, 0xFB); // write -5
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instruction.execute(&mut registers, &mut bus);
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assert_eq!(registers.pc, 0xFD);
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assert_eq!(registers.cycles, 4);
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}
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}
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@@ -1,4 +1,16 @@
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use crate::cpu::registers::Registers;
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use crate::cpu::{registers::Registers, bus::Bus};
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use crate::cpu::cycles;
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|
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pub fn do_branch_instr(registers: &mut Registers, bus: &mut Bus, condition: bool) {
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let nearlabel = bus.read(registers.get_pc_address().wrapping_add(1));
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let (bytes, cycles) = cycles::increment_cycles_branch();
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|
registers.increment_pc(bytes); registers.cycles += cycles;
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|
if condition {
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let page_boundary_crossed = do_branch(nearlabel, registers);
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let (bytes, cycles) = cycles::increment_cycles_branch_taken(page_boundary_crossed);
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|
registers.increment_pc(bytes); registers.cycles += cycles;
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|
}
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|
}
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|
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pub fn do_branch(nearlabel: u8, registers: &mut Registers) -> bool {
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pub fn do_branch(nearlabel: u8, registers: &mut Registers) -> bool {
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let is_negative = (nearlabel >> 7) != 0;
|
let is_negative = (nearlabel >> 7) != 0;
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@@ -0,0 +1,39 @@
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|
use crate::cpu::{bus::Bus, registers::Registers};
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||||||
|
|
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|
use super::{CPUInstruction, Decode};
|
||||||
|
use super::decoder_common;
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||||||
|
use super::branch_common;
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||||||
|
use super::push_common;
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||||||
|
use crate::cpu::cycles;
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|
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static INSTR_NAME: &'static str = "BRK";
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|
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pub struct BRK {}
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|
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impl CPUInstruction for BRK {
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||||||
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fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
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||||||
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push_common::do_push(registers, bus, &[registers.pbr]);
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push_common::do_push(registers, bus, &[(registers.pc >> 8) as u8, registers.pc as u8]);
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push_common::do_push(registers, bus, &[registers.p]);
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registers.set_decimal_mode_flag(false);
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registers.set_irq_disable_flag(true);
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let (bytes, cycles) = cycles::increment_cycles_brk(registers.emulation_mode);
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||||||
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registers.increment_pc(bytes); registers.cycles += cycles;
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||||||
|
}
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||||||
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}
|
||||||
|
|
||||||
|
impl Decode for BRK {
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||||||
|
fn mnemonic(&self, _registers: &Registers, _bus: &Bus, opcode: u8) -> String {
|
||||||
|
decoder_common::mnemonic_single_byte_instr(opcode, INSTR_NAME)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#[cfg(test)]
|
||||||
|
mod cpu_instructions_tests {
|
||||||
|
use super::*;
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn test() {
|
||||||
|
}
|
||||||
|
}
|
||||||
@@ -0,0 +1,61 @@
|
|||||||
|
use crate::cpu::{bus::Bus, registers::Registers};
|
||||||
|
|
||||||
|
use super::{CPUInstruction, Decode};
|
||||||
|
use super::decoder_common;
|
||||||
|
use crate::cpu::cycles;
|
||||||
|
|
||||||
|
static INSTR_NAME: &'static str = "BRL";
|
||||||
|
|
||||||
|
pub struct BRL {}
|
||||||
|
|
||||||
|
impl CPUInstruction for BRL {
|
||||||
|
fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
|
||||||
|
let label = bus.read(registers.get_pc_address()) as u16 |
|
||||||
|
((bus.read(registers.get_pc_address() + 1) as u16) << 8);
|
||||||
|
let is_negative = (label >> 15) != 0;
|
||||||
|
if is_negative {
|
||||||
|
let label = !label + 1;
|
||||||
|
registers.decrement_pc(label);
|
||||||
|
} else {
|
||||||
|
registers.increment_pc(label);
|
||||||
|
}
|
||||||
|
let (bytes, cycles) = cycles::increment_cycles_branch_long();
|
||||||
|
registers.increment_pc(bytes); registers.cycles += cycles;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl Decode for BRL {
|
||||||
|
fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
|
||||||
|
decoder_common::mnemonic_absolute(opcode, INSTR_NAME, registers, bus)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#[cfg(test)]
|
||||||
|
mod cpu_instructions_tests {
|
||||||
|
use super::*;
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn test() {
|
||||||
|
let instruction = BRL{};
|
||||||
|
// test with positive nearlabel
|
||||||
|
// branch always taken
|
||||||
|
let mut registers = Registers::new();
|
||||||
|
let mut bus = Bus::new();
|
||||||
|
registers.pc = 0x0001;
|
||||||
|
registers.cycles = 0;
|
||||||
|
bus.write(0x01, 0b00000000);
|
||||||
|
bus.write(0x02, 0b00001111);
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0x04 + 0b00001111_00000000);
|
||||||
|
assert_eq!(registers.cycles, 4);
|
||||||
|
// test with negative nearlabel and boundary cross
|
||||||
|
registers.pc = 0x00FD;
|
||||||
|
registers.cycles = 0;
|
||||||
|
bus.write(0xFD, 0xFF); // write -1
|
||||||
|
bus.write(0xFE, 0xFF); // write -1
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0xFF);
|
||||||
|
assert_eq!(registers.cycles, 4);
|
||||||
|
}
|
||||||
|
}
|
||||||
@@ -0,0 +1,59 @@
|
|||||||
|
use crate::cpu::{bus::Bus, registers::Registers};
|
||||||
|
|
||||||
|
use super::{CPUInstruction, Decode};
|
||||||
|
use super::decoder_common;
|
||||||
|
use super::branch_common;
|
||||||
|
|
||||||
|
static INSTR_NAME: &'static str = "BVC";
|
||||||
|
|
||||||
|
pub struct BVC {}
|
||||||
|
|
||||||
|
impl CPUInstruction for BVC {
|
||||||
|
fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
|
||||||
|
branch_common::do_branch_instr(registers, bus, !registers.get_overflow_flag());
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl Decode for BVC {
|
||||||
|
fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
|
||||||
|
decoder_common::mnemonic_branch_nearlabel(opcode, INSTR_NAME, registers, bus)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#[cfg(test)]
|
||||||
|
mod cpu_instructions_tests {
|
||||||
|
use super::*;
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn test() {
|
||||||
|
let instruction = BVC{};
|
||||||
|
// test with positive nearlabel
|
||||||
|
// branch not taken
|
||||||
|
let mut registers = Registers::new();
|
||||||
|
let mut bus = Bus::new();
|
||||||
|
registers.pc = 0x0000;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(true);
|
||||||
|
bus.write(0x02, 0b00001111);
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0x02);
|
||||||
|
assert_eq!(registers.cycles, 2);
|
||||||
|
// branch taken
|
||||||
|
registers.pc = 0x0000;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(false);
|
||||||
|
bus.write(0x01, 0b00001111);
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0x02 + 0b00001111);
|
||||||
|
assert_eq!(registers.cycles, 3);
|
||||||
|
// test with negative nearlabel and boundary cross
|
||||||
|
registers.pc = 0x0100;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(false);
|
||||||
|
bus.write(0x101, 0xFB); // write -5
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0xFD);
|
||||||
|
assert_eq!(registers.cycles, 4);
|
||||||
|
}
|
||||||
|
}
|
||||||
@@ -0,0 +1,59 @@
|
|||||||
|
use crate::cpu::{bus::Bus, registers::Registers};
|
||||||
|
|
||||||
|
use super::{CPUInstruction, Decode};
|
||||||
|
use super::decoder_common;
|
||||||
|
use super::branch_common;
|
||||||
|
|
||||||
|
static INSTR_NAME: &'static str = "BVS";
|
||||||
|
|
||||||
|
pub struct BVS {}
|
||||||
|
|
||||||
|
impl CPUInstruction for BVS {
|
||||||
|
fn execute(&self, registers: &mut Registers, bus: &mut Bus) {
|
||||||
|
branch_common::do_branch_instr(registers, bus, registers.get_overflow_flag());
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl Decode for BVS {
|
||||||
|
fn mnemonic(&self, registers: &Registers, bus: &Bus, opcode: u8) -> String {
|
||||||
|
decoder_common::mnemonic_branch_nearlabel(opcode, INSTR_NAME, registers, bus)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#[cfg(test)]
|
||||||
|
mod cpu_instructions_tests {
|
||||||
|
use super::*;
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn test() {
|
||||||
|
let instruction = BVS{};
|
||||||
|
// test with positive nearlabel
|
||||||
|
// branch not taken
|
||||||
|
let mut registers = Registers::new();
|
||||||
|
let mut bus = Bus::new();
|
||||||
|
registers.pc = 0x0000;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(false);
|
||||||
|
bus.write(0x02, 0b00001111);
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0x02);
|
||||||
|
assert_eq!(registers.cycles, 2);
|
||||||
|
// branch taken
|
||||||
|
registers.pc = 0x0000;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(true);
|
||||||
|
bus.write(0x01, 0b00001111);
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0x02 + 0b00001111);
|
||||||
|
assert_eq!(registers.cycles, 3);
|
||||||
|
// test with negative nearlabel and boundary cross
|
||||||
|
registers.pc = 0x0100;
|
||||||
|
registers.cycles = 0;
|
||||||
|
registers.set_overflow_flag(true);
|
||||||
|
bus.write(0x101, 0xFB); // write -5
|
||||||
|
instruction.execute(&mut registers, &mut bus);
|
||||||
|
assert_eq!(registers.pc, 0xFD);
|
||||||
|
assert_eq!(registers.cycles, 4);
|
||||||
|
}
|
||||||
|
}
|
||||||
@@ -116,3 +116,7 @@ pub fn mnemonic_branch_nearlabel(opcode: u8, instr_name: &str, registers: &Regis
|
|||||||
let nearlabel = bus.read_external(registers.get_pc_address() + 1);
|
let nearlabel = bus.read_external(registers.get_pc_address() + 1);
|
||||||
format!("{:02X} {:02X} __ __ | {} ${:02X}", opcode, nearlabel, instr_name, nearlabel)
|
format!("{:02X} {:02X} __ __ | {} ${:02X}", opcode, nearlabel, instr_name, nearlabel)
|
||||||
}
|
}
|
||||||
|
|
||||||
|
pub fn mnemonic_single_byte_instr(opcode: u8, instr_name: &str) -> String {
|
||||||
|
format!("{:02X} __ __ __ | {}", opcode, instr_name)
|
||||||
|
}
|
||||||
|
|||||||
@@ -9,8 +9,16 @@ pub mod bcc;
|
|||||||
pub mod bcs;
|
pub mod bcs;
|
||||||
pub mod beq;
|
pub mod beq;
|
||||||
pub mod bne;
|
pub mod bne;
|
||||||
|
pub mod bmi;
|
||||||
|
pub mod bpl;
|
||||||
|
pub mod bra;
|
||||||
|
pub mod brk;
|
||||||
|
pub mod brl;
|
||||||
|
pub mod bvc;
|
||||||
|
pub mod bvs;
|
||||||
pub mod decoder_common;
|
pub mod decoder_common;
|
||||||
pub mod branch_common;
|
pub mod branch_common;
|
||||||
|
pub mod push_common;
|
||||||
|
|
||||||
pub trait CPUInstruction {
|
pub trait CPUInstruction {
|
||||||
fn execute(&self, registers: &mut Registers, bus: &mut Bus);
|
fn execute(&self, registers: &mut Registers, bus: &mut Bus);
|
||||||
|
|||||||
@@ -0,0 +1,9 @@
|
|||||||
|
use crate::cpu::{registers::Registers, bus::Bus};
|
||||||
|
|
||||||
|
pub fn do_push(registers: &mut Registers, bus: &mut Bus, bytes: &[u8]) {
|
||||||
|
for byte in bytes {
|
||||||
|
let address = registers.sp as u32;
|
||||||
|
bus.write(address, *byte);
|
||||||
|
registers.decrement_sp(1);
|
||||||
|
}
|
||||||
|
}
|
||||||
Reference in New Issue
Block a user