progress: new assembler works, instruction set fully implemented with call/ret and push/pop, bf.dsa works which means the dsa assembly language works reliably. still a few bugs to fix. might be able to squeeze out a tiny bit more performance

This commit is contained in:
2026-03-09 03:24:20 +00:00
parent fc972b9b7b
commit e01a9f2808
63 changed files with 4975 additions and 1579 deletions
+653
View File
@@ -0,0 +1,653 @@
use std::{
hint::unlikely,
ops::{Add, AddAssign},
sync::{
Arc,
atomic::Ordering,
mpsc::{self, TryRecvError},
},
thread,
time::{Duration, Instant},
};
use common::{
instructions::{Instruction, Opcode},
register::Register,
};
use crate::{
Page,
config::{IoMapping, MemoryMap, RegionType},
io::{IoAccess, IoDevice, MappedDevice},
memory::{mmu::MMU, ram::RandomAccessMemory},
processor::{interrupts::Interrupt, state::SharedState},
};
pub struct Emulator<Mem: RandomAccessMemory> {
internal_state: ProcessorSnapshot,
shared_state: Arc<SharedState>,
// Interrupts
interrupts: mpsc::Receiver<u8>,
pending_fault: Option<Interrupt>,
// memory
mmu: MMU,
mainstore: Mem,
// IO
mmio: Vec<MappedDevice>,
mmio_region: Option<(u32, u32)>, // start end end of segment
// optionals - not necessarily set on boot.
memory_map: Option<MemoryMap>,
// Config params
__mmap_configured: bool,
__io_configured: bool,
}
unsafe impl<Mem: RandomAccessMemory> Send for Emulator<Mem> {}
impl<Mem: RandomAccessMemory> Emulator<Mem> {
pub fn new(mem: Mem) -> Self {
let (sender, receiver) = mpsc::channel::<u8>();
Self {
interrupts: receiver,
pending_fault: None,
internal_state: ProcessorSnapshot::default(),
shared_state: Arc::new(SharedState::new(sender)),
memory_map: None,
mmu: MMU::new(),
mainstore: mem,
// mmio
mmio: Vec::new(),
mmio_region: None,
// Config params
__io_configured: false,
__mmap_configured: false,
}
}
pub fn with_device(mut self, device: impl IoDevice + 'static) -> Self {
self.mmio.push(MappedDevice {
base: 0,
device: Box::new(device),
});
self
}
pub fn state_handle(&self) -> Arc<SharedState> {
self.shared_state.clone()
}
#[inline]
pub fn mmu_mut(&mut self) -> &mut MMU {
&mut self.mmu
}
#[inline]
pub fn memory_mut(&mut self) -> &mut impl RandomAccessMemory {
&mut self.mainstore
}
#[must_use]
#[inline]
pub fn reg(&self, reg: Register) -> u32 {
if reg as u8 == Register::Zero as u8 {
return 0;
}
debug_assert!((reg as usize) < ProcessorSnapshot::REG_COUNT);
unsafe { *self.internal_state.registers.get_unchecked(reg as usize) }
}
#[inline]
pub fn mut_reg(&mut self, reg: Register) -> &mut u32 {
debug_assert!((reg as usize) < ProcessorSnapshot::REG_COUNT);
unsafe {
self.internal_state
.registers
.get_unchecked_mut(reg as usize)
}
}
#[cold]
pub fn apply_memory_map(mut self, map: MemoryMap) -> Self {
self.mmio_region = map
.regions
.iter()
.find(|r| matches!(r.region_type, RegionType::MMIO))
.map(|r| (r.base, r.base + r.size));
map.apply(&mut self);
self.memory_map = Some(map);
self.__mmap_configured = true;
self
}
pub fn apply_io_map(mut self, map: Vec<IoMapping>) -> Result<Self, String> {
if !self.__mmap_configured {
return Err("You must map memory before applying I/O mappings".to_string());
}
for entry in map {
if let Some(idx) = self.mmio.iter().position(|d| d.device.id() == entry.device) {
self.mmio[idx].base = entry.base;
} else {
eprintln!("WARN: no device registgered for {:?}", entry.device);
}
}
self.__io_configured = true;
Ok(self)
}
#[cold]
fn update(&mut self) {
self.shared_state
.proc
.store(Arc::new(self.internal_state.clone()));
}
#[cold]
fn boot(&mut self) -> Result<(), String> {
if !(self.__io_configured && self.__mmap_configured) {
return Err("Processor not configured".to_string());
}
if let Some(map) = &self.memory_map {
MemoryMap::identity_map(&mut self.mmu, map.regions.get(0).unwrap());
}
self.internal_state.running = true;
Ok(())
}
#[cold]
fn shutdown(&mut self) {
self.internal_state.running = false;
}
#[cold]
pub fn idle_wait(&mut self) {
self.internal_state.running = false;
// Wait for an interrupt or state update to continue.
loop {
// Check for interrupts.
if let Ok(code) = self.interrupts.recv_timeout(Duration::from_millis(100)) {
self.interrupt(Interrupt::Software(code));
break;
}
// // If we've received a request to continue running. DEPRECATED (we can run through interrupts)
// if self.shared_state.running.load(Ordering::Relaxed) {
// panic!("3");
// break;
// }
// UI requested a state update.
if self.shared_state.update_req.load(Ordering::Relaxed) {
self.update();
}
}
self.internal_state.running = true;
}
pub fn run(&mut self) -> Result<(), String> {
self.boot()?;
let mut time = Instant::now();
'emu: loop {
// Update UI thread (roughly every 512k cycles targeting 60 UPS)
if unlikely(self.internal_state.clock & 0x7FFFF == 0) {
if self.shared_state.update_req.load(Ordering::Relaxed) {
self.update();
}
}
// Check for commands or hardware Interrupts every 32k cycles
if self.internal_state.clock % 0x7FFF == 0 {
if self.shared_state.running.load(Ordering::Relaxed) == false {
self.idle_wait();
}
match self.interrupts.try_recv() {
Ok(code) => self.interrupt(Interrupt::Software(code)),
Err(TryRecvError::Disconnected) => break 'emu,
Err(TryRecvError::Empty) => {}
}
}
// if we got a halt instruction, wait
if unlikely(!self.internal_state.running) {
let mips = (self.internal_state.clock as u128 / time.elapsed().as_micros());
println!(
"TIME TAKEN: {:?}, clock: {}, {}MIPS",
time.elapsed(),
self.internal_state.clock,
mips
);
time = Instant::now();
// temporary while i figure out a better solution
// exit when we hit halt (not useful for a real os ofc)
break 'emu;
self.idle_wait();
}
let pc = self.reg(Register::Pcx);
let instruction = self.mem_read_word(pc);
if cfg!(debug_assertions) {
println!(
"Clock: {} Executing {:?} PCX: {}, reg: {:?}",
self.internal_state.clock,
Instruction(instruction),
pc,
self.internal_state.registers
);
thread::sleep(Duration::from_micros(10));
}
self.mut_reg(Register::Pcx).add_assign(4);
self.execute(Instruction(instruction));
// Check if executing the interrupt caused a fault.
if let Some(fault) = self.pending_fault {
self.pending_fault = None;
println!("WARN fault: {:?}", fault);
self.interrupt(fault);
}
// always increment clock.
self.internal_state.clock += 1;
}
self.shutdown();
Ok(())
}
#[inline]
fn interrupt(&mut self, int: Interrupt) {
let idt = self.reg(Register::Idr);
*self.mut_reg(Register::Spr) -= 4;
let spr = self.reg(Register::Spr);
let pcx = self.reg(Register::Pcx);
self.mem_write_word(spr, pcx);
*self.mut_reg(Register::Pcx) = self.mem_read_word(idt + int.code() as u32 * 4)
}
#[inline]
fn execute(&mut self, word: Instruction) {
// This needs to be unsafe as we're using word.xxxx_uc() functions for decoding which are unsafe
// as they perform unchecked transmute operations (performance critical)
unsafe {
match Opcode::from_u8(word.opcode()) {
// Nothing
Some(Opcode::Nop) => {}
// move
Some(Opcode::Mov) => {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc());
}
Some(Opcode::CMov) => {
if self.reg(word.misc_uc()) != 0 {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc());
}
}
// load
Some(Opcode::Ldbs) => todo!(),
Some(Opcode::Ldhs) => todo!(),
Some(Opcode::Ldb) => {
*self.mut_reg(word.dest_uc()) = u32::from(
self.mem_read_byte(self.reg(word.src1_uc()) + word.imm16() as u32),
)
}
Some(Opcode::Ldh) => {
*self.mut_reg(word.dest_uc()) = u32::from(
self.mem_read_word(self.reg(word.src1_uc()) + word.imm16() as u32) >> 16,
)
}
Some(Opcode::Ldw) => {
*self.mut_reg(word.dest_uc()) = u32::from(
self.mem_read_word(self.reg(word.src1_uc()) + word.imm16() as u32),
)
}
// store
Some(Opcode::Stb) => {
self.mem_write_byte(
self.reg(word.dest_uc()) + word.imm16() as u32,
self.reg(word.src1_uc()) as u8,
);
}
Some(Opcode::Sth) => {
self.mem_write_byte(
self.reg(word.dest_uc()) + word.imm16() as u32,
(self.reg(word.src1_uc()) as u16 >> 8) as u8,
);
self.mem_write_byte(
self.reg(word.dest_uc()) + word.imm16() as u32 + 1,
self.reg(word.src1_uc()) as u8,
);
}
Some(Opcode::Stw) => {
self.mem_write_word(
self.reg(word.dest_uc()) + word.imm16() as u32,
self.reg(word.src1_uc()),
);
}
// load immediate
Some(Opcode::Lli) => {
*self.mut_reg(word.dest_uc()) = word.imm16() as u32;
}
Some(Opcode::Lui) => {
*self.mut_reg(word.dest_uc()) =
(word.imm16() as u32) << 16 | self.reg(word.dest_uc());
}
// Comparison
Some(Opcode::Ieq) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) == self.reg(word.src2_uc())) as u32;
}
Some(Opcode::Ine) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) != self.reg(word.src2_uc())) as u32;
}
Some(Opcode::Ilt) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) < self.reg(word.src2_uc())) as u32;
}
Some(Opcode::Ile) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) <= self.reg(word.src2_uc())) as u32;
}
Some(Opcode::Igt) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) > self.reg(word.src2_uc())) as u32;
}
Some(Opcode::Ige) => {
*self.mut_reg(word.dest_uc()) =
(self.reg(word.src1_uc()) >= self.reg(word.src2_uc())) as u32;
}
// Jump
Some(Opcode::Jmp) => {
*self.mut_reg(Register::Pcx) = self.reg(word.dest_uc()) + word.imm16() as u32
}
Some(Opcode::Jez) => {
if self.reg(word.src1_uc()) == 0 {
*self.mut_reg(Register::Pcx) =
self.reg(word.dest_uc()) + word.imm16() as u32
}
}
Some(Opcode::Jnz) => {
if self.reg(word.src1_uc()) != 0 {
*self.mut_reg(Register::Pcx) =
self.reg(word.dest_uc()) + word.imm16() as u32
}
}
Some(Opcode::Jnc) => todo!(),
Some(Opcode::Jic) => todo!(),
// Bitwise
Some(Opcode::And) => {
*self.mut_reg(word.dest_uc()) =
self.reg(word.src1_uc()) & self.reg(word.src2_uc());
}
Some(Opcode::Nand) => {
*self.mut_reg(word.dest_uc()) =
!(self.reg(word.src1_uc()) & self.reg(word.src2_uc()));
}
Some(Opcode::Or) => {
*self.mut_reg(word.dest_uc()) =
self.reg(word.src1_uc()) | self.reg(word.src2_uc());
}
Some(Opcode::Nor) => {
*self.mut_reg(word.dest_uc()) =
!(self.reg(word.src1_uc()) | self.reg(word.src2_uc()));
}
Some(Opcode::Xor) => {
*self.mut_reg(word.dest_uc()) =
self.reg(word.src1_uc()) ^ self.reg(word.src2_uc());
}
Some(Opcode::Xnor) => {
*self.mut_reg(word.dest_uc()) =
!(self.reg(word.src1_uc()) ^ self.reg(word.src2_uc()));
}
Some(Opcode::Not) => {
*self.mut_reg(word.dest_uc()) = !self.reg(word.src1_uc());
}
// Arithmetic
Some(Opcode::Add) => {
*self.mut_reg(word.dest_uc()) =
self.reg(word.src1_uc()) + self.reg(word.src2_uc());
}
Some(Opcode::Sub) => {
*self.mut_reg(word.dest_uc()) =
self.reg(word.src1_uc()) - self.reg(word.src2_uc());
}
Some(Opcode::Shl) => {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc())
<< (self.reg(word.src2_uc()) + word.shamt() as u32);
}
Some(Opcode::Shr) => {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc())
>> (self.reg(word.src2_uc()) + word.shamt() as u32);
}
Some(Opcode::Addi) => {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc()) + word.imm16() as u32;
}
Some(Opcode::Subi) => {
*self.mut_reg(word.dest_uc()) = self.reg(word.src1_uc()) - word.imm16() as u32;
}
// Utility
Some(Opcode::Push) => {
self.push(word.src1_uc());
}
Some(Opcode::Pop) => {
self.pop(word.dest_uc());
}
// Function
Some(Opcode::Call) => {
self.push(Register::Pcx);
*self.mut_reg(Register::Pcx) = self.reg(word.dest_uc()) + word.imm16() as u32
}
Some(Opcode::Ret) => {
self.pop(Register::Ret);
*self.mut_reg(Register::Pcx) = self.reg(Register::Ret);
}
Some(Opcode::Int) => {
self.interrupt(Interrupt::Software(word.imm16() as u8));
}
Some(Opcode::Hlt) => self.internal_state.running = false,
Some(Opcode::IRet) => todo!(),
None => {}
}
}
}
#[inline]
fn push(&mut self, reg: Register) {
*self.mut_reg(Register::Spr) -= 4;
self.mem_write_word(self.reg(Register::Spr), self.reg(reg));
}
#[inline]
fn pop(&mut self, reg: Register) {
*self.mut_reg(reg) = self.mem_read_word(self.reg(Register::Spr));
*self.mut_reg(Register::Spr) += 4;
}
#[inline]
fn mem_read_byte(&mut self, addr: u32) -> u8 {
if unlikely(self.is_mmio(addr)) {
return self.io_read_byte(addr);
}
self.mainstore.read_byte(addr)
}
#[inline]
fn mem_write_byte(&mut self, addr: u32, val: u8) {
if unlikely(self.is_mmio(addr)) {
self.io_write_byte(addr, val);
return;
}
self.mainstore.write_byte(addr, val);
}
#[inline]
fn mem_read_word(&mut self, addr: u32) -> u32 {
if unlikely(self.is_mmio(addr)) {
return self.io_read_word(addr);
}
self.mainstore.read_word(addr)
}
#[inline]
fn mem_write_word(&mut self, addr: u32, val: u32) {
if unlikely(self.is_mmio(addr)) {
self.io_write_word(addr, val);
return;
}
self.mainstore.write_word(addr, val);
}
#[inline]
fn mem_read_page(&mut self, addr: u32) -> &Page {
if unlikely(self.is_mmio(addr)) {
// pages spanning MMIO don't really make sense
// treat as fault
self.pending_fault = Some(Interrupt::ProtectionFault);
return &Page::ZERO;
}
self.mainstore.read_page(addr)
}
#[inline]
fn mem_write_page(&mut self, addr: u32, val: &Page) {
if unlikely(self.is_mmio(addr)) {
self.pending_fault = Some(Interrupt::ProtectionFault);
return;
}
self.mainstore.write_page(addr, val);
}
// single MMIO check reused by all of the above
#[inline]
fn is_mmio(&self, addr: u32) -> bool {
self.mmio_region
.map(|(base, end)| addr >= base && addr < end)
.unwrap_or(false)
}
fn fault(&mut self, interrupt: Interrupt) {
self.pending_fault = Some(interrupt);
}
#[inline]
fn get_device(&mut self, addr: u32) -> Option<(&mut Box<dyn IoDevice>, u32)> {
// Find the device that covers the address.
self.mmio
.iter_mut()
.find(|d| d.base <= addr && addr < d.base + d.device.size())
.map(|d| (&mut d.device, addr - d.base))
}
// --- cold IO paths ---
#[cold]
fn io_read_byte(&mut self, addr: u32) -> u8 {
if let Some((device, offset)) = self.get_device(addr) {
device.read_byte(offset).unwrap_or_else(|fault| {
self.fault(fault);
0
})
} else {
self.fault(Interrupt::UnmappedIo);
0
}
}
#[cold]
fn io_read_word(&mut self, addr: u32) -> u32 {
if let Some((device, offset)) = self.get_device(addr) {
device.read_word(offset).unwrap_or_else(|fault| {
self.fault(fault);
0
})
} else {
self.fault(Interrupt::UnmappedIo);
0
}
}
#[cold]
fn io_write_byte(&mut self, addr: u32, val: u8) {
if let Some((dev, offset)) = self.get_device(addr) {
dev.write_byte(offset, val).unwrap_or_else(|fault| {
self.fault(fault);
});
} else {
self.fault(Interrupt::UnmappedIo);
}
}
#[cold]
fn io_write_word(&mut self, addr: u32, val: u32) {
if let Some((dev, offset)) = self.get_device(addr) {
dev.write_word(offset, val).unwrap_or_else(|fault| {
self.fault(fault);
});
} else {
self.fault(Interrupt::UnmappedIo);
}
}
}
#[derive(Debug, Clone)]
pub struct ProcessorSnapshot {
pub running: bool,
pub clock: usize,
pub registers: [u32; Self::REG_COUNT],
}
impl Default for ProcessorSnapshot {
fn default() -> Self {
Self {
running: false,
clock: 0,
registers: [0; Self::REG_COUNT],
}
}
}
impl ProcessorSnapshot {
const REG_COUNT: usize = 28;
}