Add CPX and CPY.

This commit is contained in:
Andrew Keeton 2014-11-13 21:17:59 -05:00
parent 99345e2b1f
commit 0eee2e659b
1 changed files with 60 additions and 8 deletions

View File

@ -196,6 +196,22 @@ impl Machine {
self.compare_with_a_register(val);
}
(instruction::CPX, instruction::UseImmediate(val)) => {
self.compare_with_x_register(val);
}
(instruction::CPX, instruction::UseAddress(addr)) => {
let val = self.memory.get_byte(addr);
self.compare_with_x_register(val);
}
(instruction::CPY, instruction::UseImmediate(val)) => {
self.compare_with_y_register(val);
}
(instruction::CPY, instruction::UseAddress(addr)) => {
let val = self.memory.get_byte(addr);
self.compare_with_y_register(val);
}
(instruction::DEC, instruction::UseAddress(addr)) => {
self.decrement_memory(addr)
}
@ -660,6 +676,18 @@ impl Machine {
self.compare(a, val);
}
fn compare_with_x_register(&mut self, val: u8) {
debug!("compare_with_x_register");
let x = self.registers.index_x;
self.compare(x, val);
}
fn compare_with_y_register(&mut self, val: u8) {
let y = self.registers.index_y;
self.compare(y, val);
}
fn push_on_stack(&mut self, val: u8) {
let addr = self.registers.stack_pointer.to_address();
self.memory.set_byte(addr, val);
@ -1072,11 +1100,14 @@ fn branch_if_overflow_set_test() {
assert_eq!(machine.registers.program_counter, Address(0xABCD));
}
fn compare_test_helper(compare: |&mut Machine, u8|) {
fn compare_test_helper(
compare: |&mut Machine, u8|,
load_instruction: instruction::Instruction
) {
let mut machine = Machine::new();
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(127))
(load_instruction, instruction::UseImmediate(127))
);
compare(&mut machine, 127);
@ -1086,7 +1117,7 @@ fn compare_test_helper(compare: |&mut Machine, u8|) {
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(127))
(load_instruction, instruction::UseImmediate(127))
);
compare(&mut machine, 1);
@ -1096,7 +1127,7 @@ fn compare_test_helper(compare: |&mut Machine, u8|) {
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(1))
(load_instruction, instruction::UseImmediate(1))
);
compare(&mut machine, 2);
@ -1106,7 +1137,7 @@ fn compare_test_helper(compare: |&mut Machine, u8|) {
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(20))
(load_instruction, instruction::UseImmediate(20))
);
compare(&mut machine, -50);
@ -1116,7 +1147,7 @@ fn compare_test_helper(compare: |&mut Machine, u8|) {
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(1))
(load_instruction, instruction::UseImmediate(1))
);
compare(&mut machine, -1);
@ -1126,7 +1157,7 @@ fn compare_test_helper(compare: |&mut Machine, u8|) {
machine.execute_instruction(
(instruction::LDA, instruction::UseImmediate(127))
(load_instruction, instruction::UseImmediate(127))
);
compare(&mut machine, -128);
@ -1140,6 +1171,27 @@ fn compare_with_a_register_test() {
compare_test_helper(
|machine: &mut Machine, val: u8| {
machine.compare_with_a_register(val);
}
},
instruction::LDA
);
}
#[test]
fn compare_with_x_register_test() {
compare_test_helper(
|machine: &mut Machine, val: u8| {
machine.compare_with_x_register(val);
},
instruction::LDX
);
}
#[test]
fn compare_with_y_register_test() {
compare_test_helper(
|machine: &mut Machine, val: u8| {
machine.compare_with_y_register(val);
},
instruction::LDY
);
}