more optimisations test program ~54MIPS -> ~110MIPS

emulator/src/emulator/system/cache.rs

@@ -0,0 +1,53 @@
+use common::prelude::Instruction;
+use rustc_hash::FxHashMap;
+
+#[derive(Debug)]
+pub struct Cache {
+    addr: u32,
+    instruction_block: Option<[u8; 256]>,
+    instruction_lookup: FxHashMap<u32, Instruction>,
+}
+
+impl Cache {
+    #[must_use]
+    pub fn new() -> Self {
+        Self {
+            addr: 0,
+            instruction_block: None,
+            instruction_lookup: FxHashMap::default(),
+        }
+    }
+
+    pub fn lookup_value(&mut self, addr: u32) -> Option<u32> {
+        if addr < self.addr || addr >= self.addr + 256 || self.instruction_block.is_none()
+        {
+            return None;
+        }
+
+        Some(u32::from_be_bytes(
+            self.instruction_block.expect("this should not be none!")
+                [(addr - self.addr) as usize..(addr - self.addr + 4) as usize]
+                .try_into()
+                .expect("Failed to convert bytes to u32"),
+        ))
+    }
+
+    pub const fn set(&mut self, addr: u32, block: &[u8; 256]) {
+        self.addr = addr - addr % 256;
+        self.instruction_block = Some(*block);
+    }
+
+    pub fn lookup_instruction(&mut self, instruction: u32) -> Option<Instruction> {
+        self.instruction_lookup.get(&instruction).copied()
+    }
+
+    pub fn insert(&mut self, value: u32, instruction: Instruction) {
+        self.instruction_lookup.insert(value, instruction);
+    }
+}
+
+impl Default for Cache {
+    fn default() -> Self {
+        Self::new()
+    }
+}

emulator/src/emulator/system/emulator.rs

@@ -25,9 +25,11 @@ pub fn run_emulator(
     let mut running = Running::Paused;
     let mut step = 0;
     let mut addr;
-    let mut history = Vec::<(u32, Instruction)>::with_capacity(32768);
+    let mut history = Vec::<(u32, u32)>::with_capacity(32768);
     let size = 256;
 
+    let record_history = true;
+
     state_tx
         .send(StateUpdate::Running(Running::Paused))
         .expect("Failed to send initial state!");
@@ -164,33 +166,11 @@ pub fn run_emulator(
             }
         }
 
-        if running == Running::Paused && step > 0 {
-            step -= 1;
-            update = true;
-
-            // Execute one cycle.
-            match processor.cycle() {
-                Ok((addr, instruction)) => {
-                    history.push((addr, instruction));
-                }
-                Err(why) => {
-                    let pcx = processor
-                        .get(Register::Pcx)
-                        .expect("SPR should never be invalid");
-                    report_err(
-                        state_tx,
-                        &format!(
-                            "Could not decode instruction at {pcx:x}. Reason: {why}"
-                        ),
-                        &mut processor,
-                    );
-                }
-            }
-            instruction_count += 1;
-            continue;
-        }
-
         if running == Running::Running {
+            step += 1;
+        }
+
+        if step > 0 {
             step -= 1;
             update = true;
 
@@ -212,8 +192,16 @@ pub fn run_emulator(
                 }
             };
 
-            history.push(instruction);
+            if record_history {
-            if matches!(instruction.1, Instruction::Halt) {
+                history.push((
+                    instruction.0,
+                    processor
+                        .get(Register::Cir)
+                        .expect("CIR should never be invalid"),
+                ));
+            }
+
+            if matches!(instruction, (_, Instruction::Halt)) {
                 running = Running::Halted;
                 step = 0;
             }

emulator/src/emulator/system/memory.rs

@@ -36,15 +36,7 @@ pub struct MainStore {
     pub data: FxHashMap<u32, Block>,
 }
 
-pub struct Block {
+pub type Block = [u8; 256];
-    data: [u8; 256],
-}
-
-impl Default for Block {
-    fn default() -> Self {
-        Self { data: [0; 256] }
-    }
-}
 
 impl Default for MainStore {
     fn default() -> Self {
@@ -67,12 +59,12 @@ impl MainStore {
 
     #[inline]
     fn mut_block(&mut self, addr: u32) -> &mut Block {
-        self.data.entry(addr).or_default()
+        self.data.entry(addr).or_insert([0; 256])
     }
 
     #[inline]
     fn block(&mut self, addr: u32) -> &Block {
-        self.data.entry(addr).or_default()
+        self.data.entry(addr).or_insert([0; 256])
     }
 }
 
@@ -86,7 +78,7 @@ impl MemoryUnit for MainStore {
     fn read_byte(&mut self, addr: u32) -> u8 {
         let (block_addr, offset) = Self::segment_addr(addr);
         let block = self.block(block_addr);
-        block.data[offset as usize]
+        block[offset as usize]
     }
 
     #[inline]
@@ -99,7 +91,7 @@ impl MemoryUnit for MainStore {
         let offset = offset as usize;
         let block = self.block(block_addr);
         Ok(u32::from_be_bytes(
-            block.data[offset..=offset + 3]
+            block[offset..=offset + 3]
                 .try_into()
                 .expect("Failed to read word!"),
         ))
@@ -119,7 +111,7 @@ impl MemoryUnit for MainStore {
     fn write_byte(&mut self, addr: u32, value: u8) {
         let (block_addr, offset) = Self::segment_addr(addr);
         let block = self.mut_block(block_addr);
-        block.data[offset as usize] = value;
+        block[offset as usize] = value;
     }
 
     #[inline]
@@ -130,7 +122,7 @@ impl MemoryUnit for MainStore {
 
         let (block_addr, offset) = Self::segment_addr(addr);
         let block = self.mut_block(block_addr);
-        block.data[offset as usize..=(offset + 3) as usize]
+        block[offset as usize..=(offset + 3) as usize]
             .copy_from_slice(&value.to_be_bytes());
         Ok(())
     }
@@ -141,7 +133,7 @@ impl MemoryUnit for MainStore {
         let mut current_block = self.mut_block(current_block_addr);
         let mut offset = addr % 256;
         for byte in value {
-            current_block.data[offset as usize] = byte;
+            current_block[offset as usize] = byte;
             offset += 1;
             if offset >= 256 {
                 offset = 0;
@@ -154,12 +146,12 @@ impl MemoryUnit for MainStore {
     #[inline]
     fn read_block(&mut self, addr: u32) -> &[u8; 256] {
         let (block_addr, _) = Self::segment_addr(addr);
-        &self.block(block_addr).data
+        self.block(block_addr)
     }
 
     #[inline]
     fn write_block(&mut self, addr: u32, data: &[u8; 256]) {
         let (block_addr, _) = Self::segment_addr(addr);
-        let _ = self.data.insert(block_addr, Block { data: *data });
+        let _ = self.data.insert(block_addr, *data);
     }
 }

emulator/src/emulator/system/mod.rs

@@ -1,3 +1,4 @@
+pub mod cache;
 pub mod emulator;
 pub mod memory;
 pub mod model;

emulator/src/emulator/system/model.rs

@@ -78,7 +78,7 @@ pub struct State {
 
     pub error_log: Vec<String>,
 
-    pub instruction_history: Vec<(u32, Instruction)>,
+    pub instruction_history: Vec<(u32, u32)>,
 }
 
 impl State {
@@ -154,7 +154,7 @@ pub enum StateUpdate {
     MemoryView(Vec<u8>),
     DisplayView(Vec<u8>),
     Error(String),
-    InstructionHistory(Vec<(u32, Instruction)>),
+    InstructionHistory(Vec<(u32, u32)>),
 }
 
 #[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]

emulator/src/emulator/system/processor/mod.rs

@@ -4,6 +4,7 @@ use std::{
 };
 
 use crate::emulator::system::{
+    cache::Cache,
     memory::MemoryUnit,
     model::{IODevice, ProcessorError, RegFile},
 };
@@ -17,6 +18,7 @@ pub struct Processor {
     pub io_devices: Vec<Arc<dyn IODevice>>,
 
     pub void: u32,
+    pub cache: Cache,
 }
 
 fn log(message: &str) {
@@ -32,6 +34,7 @@ impl Processor {
             halted: false,
             io_devices,
             void: 0,
+            cache: Cache::new(),
         }
     }
 
@@ -55,17 +58,31 @@ impl Processor {
 
         // Set MAR to the previous value of PCX.
         *self.reg(Register::Mar)? = addr;
-        let val = self.memory.read_word(addr)?;
+
+        let encoded = if let Some(val) = self.cache.lookup_value(addr) {
+            val
+        } else {
+            let block = self.memory.read_block(addr);
+            self.cache.set(addr, block);
+            self.cache
+                .lookup_value(addr)
+                .expect("Failed to lookup value!")
+        };
 
         // Set CIR to the value of RAM[MAR].
-        *self.reg(Register::Mar)? = val;
+        *self.reg(Register::Cir)? = encoded;
 
-        // Decode and execute the instruction.
+        let decoded = if let Some(val) = self.cache.lookup_instruction(addr) {
-        let instruction = Instruction::decode(val)
+            val
-            .map_err(|_| ProcessorError::InvalidInstruction(val))?;
+        } else {
+            let decoded = Instruction::decode(encoded)
+                .map_err(|_| ProcessorError::InvalidInstruction(encoded))?;
+            self.cache.insert(addr, decoded);
+            decoded
+        };
 
-        instruction.execute(self)?;
+        decoded.execute(self)?;
-        Ok((addr, instruction))
+        Ok((addr, decoded))
     }
 
     const fn fetch(&self) -> Result<u32, ProcessorError> {

emulator/src/emulator/ui/history.rs

@@ -1,3 +1,4 @@
+use common::prelude::Instruction;
 use egui::{Context, Ui};
 
 use crate::emulator::{
@@ -57,8 +58,11 @@ impl Component for History {
                                     .color(egui::Color32::from_rgb(255, 200, 200)),
                             );
 
+                            let decoded = Instruction::decode(instruction.1)
+                                .unwrap_or(Instruction::Nop);
+
                             ui.label(
-                                egui::RichText::new(instruction.1.to_string())
+                                egui::RichText::new(decoded.to_string())
                                     .font(egui::FontId::monospace(12.0))
                                     .color(egui::Color32::from_rgb(200, 255, 200)),
                             );

resources/dsa/main.dsa

@@ -1,80 +1,12 @@
-include fib: "./lib/maths/fib.dsa" 
+// program to just test compute power
-include maths: "./lib/maths/core.dsa"
-include print: "./lib/io/print.dsa"
 
-dw idt: 0xFFFF0000
+dw large_num: 0x333333 // 333,333 instructions
-dw stack: 0x10000
-init:
-	// setup interrupt handlers
-	ldw idt, idr
-	lwi handle_hard_fault, rg0
-	stw rg0, idr, 4
-	// set up a stack.
-	ldw stack, bpr
-	mov bpr, spr
-
-dw string: "hello world"
 start:
+	ldw large_num, rg0
 
-	lwi 37, rg0
+// run approx 1m instructions
-	lwi 12, rg1
+loop:
-	push rg0
+	dec rg0
-	push rg1
+	cmp rg0, zero
-	call maths::divmod
+	jgt loop
-	pop rg0 // result
-	pop rg1 // remainder
-
-	push rg1
-	push rg0
-	call print::print_hex_byte
-	call print::print_whitespace
-	pop zero
-	call print::print_hex_byte
-	call print::print_newline
-
-	lwi string, rg0
-    //lwi 10, rg0
-    pusha 4
-	push rg0
-	call print::print
-    //call fib::fib_n
-    pop zero
-	call print::print_newline
-	popa 4
-
-	pusha 4
-	push rg0
-	call print::print
-    //call fib::fib_n
-    pop zero
-	call print::print_newline
-	popa 4
-
-	pusha 4
-	push rg0
-	call print::print
-    //call fib::fib_n
-    pop zero
-	call print::print_newline
-	popa 4
-
-	pusha 4
-	push rg0
-	call print::print
-    //call fib::fib_n
-    pop zero
-	call print::print_newline
-	popa 4
-
-    hlt
-
-// fault handler in case we fail DSA.
-dw hard_fault_err: "FATAL: Illegal Instruction or Memory Access!"
-handle_hard_fault:
-	call print::clear
-	call print::reset
-	lwi hard_fault_err, rg0
-	push rg0
-	call print::print
-	pop zero
     hlt