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Fix V8 emulator bugs

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This commit is contained in:
Asraelite 2024-01-09 21:05:38 +01:00
parent c45ad79440
commit 476972f85a
29 changed files with 281 additions and 18 deletions
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11
assembler/targets/parva_0_1.ts
View file

@ -618,6 +618,7 @@ class ParvaEmulator implements Emulator {
screen: [] as Array<Array<number>>,
screenBuffer: [] as Array<Array<number>>,
};
previousFrameAccessedMemory: boolean = false;
constructor() { }
@ -632,6 +633,12 @@ class ParvaEmulator implements Emulator {
}
step() {
}
stepCore(): boolean {
let coreTerminates = false;
const instruction = this.memory[this.pc] ?? 0;
const bits = instruction.toString(2).padStart(24, '0');
@ -715,6 +722,8 @@ class ParvaEmulator implements Emulator {
this.memory[address + 1] = valueD1;
}
}
this.previousFrameAccessedMemory = true;
} else if (operationType === '11') {
// branching
const special = condition.startsWith('11');
@ -747,6 +756,7 @@ class ParvaEmulator implements Emulator {
result = !result;
}
if (result) {
coreTerminates = true;
this.pc = targetAddress - 1;
}
}
@ -755,6 +765,7 @@ class ParvaEmulator implements Emulator {
this.pc &= 0xffffff;
this.cycle += 1;
this.cycle &= 0xffffff;
return coreTerminates;
}
ioOut(device: number, command: number, valueA: number, valueB: number) {

30
assembler/targets/v8.ts
View file

@ -440,16 +440,16 @@ class V8Emulator implements Emulator {
this.pc = this.memory[immediate] ?? 0;
} else if (bits === '00000100') {
// jz imm
this.pc = this.registers[0] === 0 ? immediate : this.pc + 1;
this.pc = this.zeroFlag ? immediate : this.pc + 2;
} else if (bits === '00000101') {
// jnz imm
this.pc = this.registers[0] !== 0 ? immediate : this.pc + 1;
this.pc = !this.zeroFlag ? immediate : this.pc + 2;
} else if (bits === '00000110') {
// jc imm
this.pc = this.carryFlag ? immediate : this.pc + 1;
this.pc = this.carryFlag ? immediate : this.pc + 2;
} else if (bits === '00000111') {
// jnc imm
this.pc = !this.carryFlag ? immediate : this.pc + 1;
this.pc = !this.carryFlag ? immediate : this.pc + 2;
} else if (bits === '00001000') {
// jsr imm
this.push(this.pc + 2);
@ -486,16 +486,16 @@ class V8Emulator implements Emulator {
this.aluOp(operand, (x, a) => x + a + (this.carryFlag ? 1 : 0));
} else if (bits.startsWith('00011')) {
// inc
this.aluOp(operand, (x, a) => x + 1);
this.aluOp(operand, (x, a) => x + 1, false);
} else if (bits.startsWith('00100')) {
// sbc
this.aluOp(operand, (x, a) => x - a - (this.carryFlag ? 1 : 0));
} else if (bits.startsWith('00101')) {
// dec
this.aluOp(operand, (x, a) => x - 1);
this.aluOp(operand, (x, a) => x - 1, false);
} else if (bits.startsWith('00110')) {
// not
this.aluOp(operand, (x, a) => (~x) & 0xff);
this.aluOp(operand, (x, a) => (~x) & 0xff, false);
} else if (bits.startsWith('00111')) {
// xor
this.aluOp(operand, (x, a) => x ^ a);
@ -519,11 +519,11 @@ class V8Emulator implements Emulator {
this.pc += 1;
} else if (bits.startsWith('01100')) {
// rol
this.aluOp(operand, (x, a) => (x << 1) + (x >>> 7));
this.aluOp(operand, (x, a) => (x << 1) + (x >>> 7), false);
} else if (bits.startsWith('01101')) {
// ror
const initialValue = this.getRegister(operand);
this.aluOp(operand, (x, a) => (x >>> 1) + ((x & 1) << 7));
this.aluOp(operand, (x, a) => (x >>> 1) + ((x & 1) << 7), false);
this.carryFlag = (initialValue & 1) === 1;
} else if (bits.startsWith('01110')) {
// cmp
@ -575,13 +575,13 @@ class V8Emulator implements Emulator {
}
}
aluOp(register: string, fn: (x: number, a: number) => number) {
aluOp(register: string, fn: (x: number, a: number) => number, destinationIsA = true) {
const operandValue = this.getRegister(register);
const aValue = this.registers[0];
const result = fn(operandValue, aValue);
this.zeroFlag = result === 0;
this.carryFlag = result > 0xff;
this.registers[0] = result & 0xff;
this.carryFlag = (result & 0xff) !== result;
this.setRegister(destinationIsA ? '0' : register, result & 0xff);
this.pc += 1;
}
@ -634,8 +634,12 @@ class V8Emulator implements Emulator {
memoryString += ' ';
}
}
const controlRegistersString = `<span style="background-color: #fcb55b">pc: ${this.pc.toString(16).padStart(2, '0')}</span>, `
+ `<span style="background-color: cyan">stack pointer: ${this.memory[STACK_POINTER_ADDRESS].toString(16).padStart(2, '0')}</span>, `
+ `carry flag: ${this.carryFlag ? 1 : 0}, `
+ `zero flag: ${this.zeroFlag ? 1 : 0}`;
return `
<pre><span style="background-color: #fcb55b">pc: ${this.pc.toString(16).padStart(2, '0')}</span>,<span style="background-color: cyan"> stack pointer: ${this.memory[STACK_POINTER_ADDRESS].toString(16).padStart(2, '0')}</span></pre>
<pre>${controlRegistersString}</pre>
<pre>${registersString}</pre>
<pre>memory:\n${memoryString}</pre>
`;