updated compiler to support multiple frontends and backends

Cargo.toml

@@ -1,7 +1,7 @@
 cargo-features = ["codegen-backend"]
 
 [workspace]
-members = ["emulator", "common", "assembler", "dsa_editor", "compiler", "c_compiler"]
+members = ["emulator", "common", "assembler", "dsa_editor", "compiler"]
 resolver = "3"
 
 [workspace.package]

compiler/src/backend/dsa/codegen.rs

@@ -0,0 +1,738 @@
+use std::collections::HashMap;
+use std::sync::atomic::AtomicU32;
+use std::time::SystemTime;
+
+use chrono::{DateTime, Local};
+
+use super::registers::RegisterAllocator;
+use crate::{block, comment, dsa};
+
+use crate::model::{
+    BinaryOperator, CompilerError, ConstExpr, Declaration, Dependency, Expression,
+    Program, Statement, UnaryOperator, Variable,
+};
+
+pub struct CodeGenerator {
+    ast: Program,
+    imports: HashMap<String, String>,
+    globals: Vec<String>,
+    functions: Vec<String>,
+    symbols: Vec<String>,
+    allocator: RegisterAllocator,
+}
+
+fn import(name: &str, path: &str) -> String {
+    format!("include {name}: \"{}\"", path)
+}
+
+impl CodeGenerator {
+    const RET: &'static str = "\tjmp _ret";
+
+    pub fn new(ast: Program) -> Self {
+        CodeGenerator {
+            ast,
+            imports: HashMap::new(),
+            globals: Vec::new(),
+            functions: Vec::new(),
+            symbols: Vec::new(),
+            allocator: RegisterAllocator::new(),
+        }
+    }
+
+    pub fn include(&mut self, name: &str, path: &str) {
+        self.imports.insert(name.to_string(), path.to_string());
+    }
+
+    fn is_global(&self, name: &str) -> bool {
+        // Check if this variable is in the globals list
+        self.globals
+            .iter()
+            .any(|g| g.contains(&format!("dw {}:", name)))
+    }
+
+    pub fn generate(&mut self) -> Result<String, CompilerError> {
+        // always include the print library for debugging!
+        self.include("print", "./lib/io/print.dsa");
+
+        for block in self.ast.clone().declarations {
+            match block {
+                Declaration::Variable {
+                    var: Variable { name, .. },
+                    ..
+                } => self.symbols.push(name),
+                Declaration::Function { name, .. } => self.symbols.push(name),
+                Declaration::Dependency(Dependency { name, .. }) => {
+                    self.symbols.push(name)
+                }
+            }
+        }
+
+        for block in self.ast.clone().declarations {
+            self.generate_block(block.clone())?;
+        }
+
+        self.generate_layout()
+    }
+
+    fn generate_layout(&mut self) -> Result<String, CompilerError> {
+        let datetime: DateTime<Local> = SystemTime::now().into();
+        Ok(dsa![
+            "",
+            comment!("GENERATED BY DSC COMPILER"),
+            comment!(format!(
+                "Generated at {}",
+                datetime.format("%Y-%m-%d %H:%M:%S")
+            )),
+            "",
+            // imports
+            comment!("Imports"),
+            self.imports
+                .iter()
+                .map(|(k, v)| import(k, v))
+                .collect::<Vec<String>>()
+                .join("\n"),
+            "",
+            // reserved memory
+            comment!("Globals & Reserved Memory"),
+            self.globals.join("\n"),
+            "",
+            // entry point
+            comment!("Entry Point"),
+            "dw stack: 0x10000",
+            "db message: \"Process Exited with code:\"",
+            block! [ "_init"
+                dsa![ldw stack, bpr],
+                dsa![mov bpr, spr],
+                dsa![push zero],
+                dsa![call main],
+                dsa![call print::print_newline],
+                dsa![lwi message, rg0],
+                dsa![push rg0],
+                dsa![call print::print],
+                dsa![pop zero],
+                dsa![call print::print_hex_word],
+                dsa![pop zero],
+                dsa![hlt]
+            ],
+            "",
+            comment!("Return"),
+            block! [ "_ret"
+                dsa![mov bpr, spr],
+                dsa![pop bpr],
+                dsa![return]
+            ],
+            comment!("Compiled Code Starts..."),
+            // block! [ "main"
+            //     dsa![push bpr],
+            //     dsa![mov spr, bpr],
+            //     dsa![lwi 67, rg1],
+            //     dsa![stw rg1, spr, 8],
+            //     dsa![mov bpr, spr],
+            //     dsa![pop bpr],
+            //     dsa![return]
+            // ],
+            self.functions.join("\n"),
+        ])
+    }
+
+    fn generate_global(&mut self, name: &str, init: Option<ConstExpr>) {
+        self.globals.push(format!(
+            "dw {}: {}",
+            name,
+            init.unwrap_or(ConstExpr::Number(0))
+        ))
+    }
+
+    fn generate_block(&mut self, block: Declaration) -> Result<(), CompilerError> {
+        match block {
+            Declaration::Variable { var, init, .. } => {
+                self.generate_global(&var.name, init)
+            }
+            Declaration::Function {
+                name, params, body, ..
+            } => {
+                let func = self.generate_function(&name, &params, &body).join("\n");
+
+                self.functions.push(format!("{func}\n"));
+            }
+            Declaration::Dependency(Dependency { name, path }) => {
+                self.imports.insert(name, path);
+            }
+        };
+
+        Ok(())
+    }
+
+    // Example: Generate code for a function
+    fn generate_function(
+        &mut self,
+        name: &str,
+        params: &[Variable],
+        body: &[Statement],
+    ) -> Vec<String> {
+        let mut code = Vec::new();
+
+        // Reset allocator for new function
+        self.allocator.reset();
+
+        // Function prologue
+        code.push(format!("{}:", name));
+        code.push("\tpush bpr".to_string());
+        code.push("\tmov spr, bpr".to_string());
+        code.push(String::new());
+
+        // Allocate parameters to registers or stack locations
+        for (i, param) in params.iter().enumerate() {
+            let offset = 8 + (i as i32 * 4); // Parameters start at bpr+8
+            // Track that this parameter is at a stack location
+            let (reg, load_code) = self.allocator.alloc_var(&param.name).unwrap();
+            code.extend(load_code);
+            code.push(format!("\tldw bpr, {}, {}", reg, offset));
+        }
+
+        // Generate code for function body
+        for stmt in body {
+            let stmt_code = self.generate_statement(stmt).unwrap();
+            code.extend(stmt_code);
+        }
+
+        // automatically return at function end
+        if let Some(x) = code.last()
+            && x == Self::RET
+        {
+        } else {
+            code.push(Self::RET.to_string());
+        }
+
+        code
+    }
+
+    // Example: Generate code for a statement
+    fn generate_statement(
+        &mut self,
+        stmt: &Statement,
+    ) -> Result<Vec<String>, CompilerError> {
+        let mut code = Vec::new();
+
+        match stmt {
+            Statement::Declaration { var, value } => {
+                if let Some(expr) = value {
+                    // Evaluate expression
+                    let (result_reg, expr_code) = self.generate_expression(expr, true)?;
+                    code.extend(expr_code);
+
+                    // Store result in variable
+                    let store_code = self.allocator.store_var(&var.name, &result_reg);
+                    code.extend(store_code);
+
+                    // Free temporary register
+                    self.allocator.free_temp(&result_reg);
+                } else {
+                    // Just declaring variable without initialization
+                    self.allocator.alloc_var(&var.name)?;
+                }
+            }
+
+            Statement::Break => unimplemented!(),
+            Statement::Continue => unimplemented!(),
+
+            Statement::PtrWrite { ptr, value } => {
+                let (result_reg, expr_code) = self.generate_expression(value, true)?;
+                code.extend(expr_code);
+
+                let (ptr_reg, ptr_code) = self.generate_expression(ptr, true)?;
+                code.extend(ptr_code);
+
+                code.push(format!("\tstw {}, {}", result_reg, ptr_reg));
+
+                self.allocator.free_temp(&result_reg);
+                self.allocator.free_temp(&ptr_reg);
+            }
+
+            Statement::Assign { varname, value } => {
+                // Evaluate expression
+                let (result_reg, expr_code) = self.generate_expression(value, true)?;
+                code.extend(expr_code);
+
+                // Check if this is a global variable
+                if self.is_global(varname) {
+                    // Store to global label
+                    code.push(format!("\tstw {}, {}", result_reg, varname));
+                } else {
+                    // Store result in local variable
+                    let store_code = self.allocator.store_var(varname, &result_reg);
+                    code.extend(store_code);
+                }
+
+                // Free temporary register
+                self.allocator.free_temp(&result_reg);
+            }
+
+            Statement::Return(expr) => {
+                if let Some(e) = expr {
+                    let (result_reg, expr_code) = self.generate_expression(e, true)?;
+                    code.extend(expr_code);
+                    code.push(format!("\tstw {}, bpr, 8", result_reg));
+                    code.push(format!("\tjmp _ret"));
+                    self.allocator.free_temp(&result_reg);
+                }
+            }
+
+            Statement::If {
+                condition,
+                then_stmt,
+                else_stmt,
+            } => {
+                // Generate condition
+                let (cond_reg, cond_code) = self.generate_expression(condition, true)?;
+                code.extend(cond_code);
+
+                // Compare with zero
+                code.push(format!("\tcmp {}, zero", cond_reg));
+                self.allocator.free_temp(&cond_reg);
+
+                // Generate unique labels
+                let then_label = format!("_then_{}", self.get_unique_label());
+                let else_label = format!("_else_{}", self.get_unique_label());
+                let end_label = format!("_end_{}", self.get_unique_label());
+
+                // Jump to else if condition is false (equal to zero)
+                code.push(format!("\tjeq {}", else_label));
+
+                // Then block
+                code.push(format!("{}:", then_label));
+                for s in then_stmt {
+                    code.extend(self.generate_statement(s)?);
+                }
+
+                if then_stmt.len() == 0 {
+                    code.push("\tnop".to_string());
+                }
+
+                code.push(format!("\tjmp {}", end_label));
+
+                // Else block
+                code.push(format!("{}:", else_label));
+                for s in else_stmt {
+                    code.extend(self.generate_statement(s)?);
+                }
+
+                if else_stmt.len() == 0 {
+                    code.push("\tnop".to_string());
+                }
+
+                code.push(format!("{}:", end_label));
+            }
+
+            Statement::While { condition, body } => {
+                let loop_start = format!("_while_start_{}", self.get_unique_label());
+                let loop_end = format!("_while_end_{}", self.get_unique_label());
+
+                code.push(format!("{}:", loop_start));
+
+                // Generate condition
+                let (cond_reg, cond_code) = self.generate_expression(condition, true)?;
+                code.extend(cond_code);
+
+                code.push(format!("\tcmp {}, zero", cond_reg));
+                self.allocator.free_temp(&cond_reg);
+
+                code.push(format!("\tjeq {}", loop_end));
+
+                // Loop body
+                for s in body {
+                    code.extend(self.generate_statement(s)?);
+                }
+
+                code.push(format!("\tjmp {}", loop_start));
+                code.push(format!("{}:", loop_end));
+            }
+
+            Statement::Loop(body) => {
+                let loop_start = format!("_loop_start_{}", self.get_unique_label());
+
+                code.push(format!("{}:", loop_start));
+
+                for s in body {
+                    code.extend(self.generate_statement(s)?);
+                }
+
+                code.push(format!("\tjmp {}", loop_start));
+            }
+
+            Statement::Expression { expr } => {
+                let (result_reg, expr_code) = self.generate_expression(expr, false)?;
+                code.extend(expr_code);
+                self.allocator.free_temp(&result_reg);
+            }
+
+            Statement::Block(statements) => {
+                for s in statements {
+                    code.extend(self.generate_statement(s)?);
+                }
+            }
+        }
+
+        Ok(code)
+    }
+
+    // Example: Generate code for an expression
+    // Returns (register containing result, assembly code)
+    fn generate_expression(
+        &mut self,
+        expr: &Expression,
+        use_result: bool,
+    ) -> Result<(String, Vec<String>), CompilerError> {
+        let mut code = Vec::new();
+
+        // optimisation to prevent generating dead code!
+        if expr.is_pure() && !use_result {
+            return Ok((String::new(), code));
+        }
+
+        match expr {
+            Expression::StringLiteral(value) => {
+                let (reg, alloc_code) = self.allocator.alloc_temp()?;
+                code.extend(alloc_code);
+
+                // write string into memory
+                let uuid = self.get_unique_label();
+                code.push(format!("\tdb str_{uuid}: \"{value}\""));
+
+                // Load pointer to string
+                code.push(format!("\tlwi str_{uuid}, {reg}"));
+
+                Ok((reg, code))
+            }
+
+            Expression::CharLiteral(value) => {
+                let (reg, alloc_code) = self.allocator.alloc_temp()?;
+                code.extend(alloc_code);
+
+                // Load immediate value
+                code.push(format!("\tlli {}, {} // '{value}'", *value as u8, reg));
+
+                Ok((reg, code))
+            }
+
+            Expression::Number(value) => {
+                let (reg, alloc_code) = self.allocator.alloc_temp()?;
+                code.extend(alloc_code);
+
+                // Load immediate value
+                code.push(format!("\tlli {}, {}", value & 0xFFFF, reg));
+                if *value > 0xFFFF || *value < 0 {
+                    code.push(format!("\tlui {}, {}", (value >> 16) & 0xFFFF, reg));
+                }
+
+                Ok((reg, code))
+            }
+
+            Expression::Variable { name, .. } => {
+                if self.is_global(&name.name) {
+                    // Allocate a temporary register for the global
+                    let (reg, alloc_code) = self.allocator.alloc_temp()?;
+                    code.extend(alloc_code);
+
+                    // Load from global label
+                    code.push(format!("\tldw {}, {}", name.name, reg));
+
+                    Ok((reg, code))
+                } else {
+                    // Local variable - use existing allocator logic
+                    let (reg, load_code) = self.allocator.load_var(&name.name)?;
+                    code.extend(load_code);
+                    Ok((reg, code))
+                }
+            }
+
+            Expression::Binary { op, left, right } => {
+                // Evaluate left operand
+                let (left_reg, left_code) = self.generate_expression(left, true)?;
+                code.extend(left_code);
+
+                // Evaluate right operand
+                let (right_reg, right_code) = self.generate_expression(right, true)?;
+                code.extend(right_code);
+
+                // Allocate result register
+                let (result_reg, result_alloc) = self.allocator.alloc_temp()?;
+                code.extend(result_alloc);
+
+                // Generate operation
+                match op {
+                    BinaryOperator::Add => {
+                        code.push(format!(
+                            "\tadd {}, {}, {}",
+                            left_reg, right_reg, result_reg
+                        ));
+                    }
+                    BinaryOperator::Sub => {
+                        code.push(format!(
+                            "\tsub {}, {}, {}",
+                            left_reg, right_reg, result_reg
+                        ));
+                    }
+                    BinaryOperator::Mul => {
+                        self.include("maths", "./lib/maths/core.dsa");
+                        // Call multiply function
+                        code.push(format!("\tpush {}", right_reg));
+                        code.push(format!("\tpush {}", left_reg));
+                        code.push("\tcall maths::multiply".to_string());
+                        code.push(format!("\tpop {}", result_reg));
+                        code.push("\tpop zero".to_string());
+                    }
+                    // Comparison operators - return 1 (true) or 0 (false)
+                    BinaryOperator::Eq => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjne {}", end_label)); // If not equal, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    BinaryOperator::Ne => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjeq {}", end_label)); // If equal, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    BinaryOperator::Lt => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjge {}", end_label)); // If greater or equal, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    BinaryOperator::Le => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjgt {}", end_label)); // If greater than, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    BinaryOperator::Gt => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjle {}", end_label)); // If less or equal, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    BinaryOperator::Ge => {
+                        code.push(format!("\tcmp {}, {}", left_reg, right_reg));
+                        code.push(format!("\tlli 0, {}", result_reg));
+                        let end_label = format!("_cmp_end_{}", self.get_unique_label());
+                        code.push(format!("\tjlt {}", end_label)); // If less than, skip setting to 1
+                        code.push(format!("\tlli 1, {}", result_reg));
+                        code.push(format!("{}:", end_label));
+                    }
+                    _ => unimplemented!(),
+                }
+
+                // Free operand registers (allocator will protect variables)
+                self.allocator.free_temp(&left_reg);
+                self.allocator.free_temp(&right_reg);
+
+                Ok((result_reg, code))
+            }
+
+            Expression::Call { name, args } => {
+                // first evaluate all the args we're going to need
+                let mut arg_regs = Vec::new();
+                for arg in args.iter().rev() {
+                    let (arg_reg, arg_code) = self.generate_expression(arg, true)?;
+                    code.extend(arg_code);
+                    arg_regs.push(arg_reg);
+                }
+
+                // Save caller-saved registers and track which ones we saved
+                // old method, inefficient.
+                // let saved_regs = self.allocator.get_caller_saved_registers();
+                // for reg in &saved_regs {
+                //     code.push(format!("\tpush {}", reg));
+                // }
+
+                // Save caller-saved registers and track which ones we saved
+                let saved_regs = self.allocator.get_caller_saved_registers();
+                for reg in &saved_regs {
+                    // spill variables to stack
+                    code.extend(self.allocator.spill_register(reg).unwrap());
+                }
+
+                // Evaluate and push arguments in reverse order
+                for (i, arg_reg) in arg_regs.iter().enumerate() {
+                    code.push(format!(
+                        "\tpush {} // push arg {}",
+                        arg_reg,
+                        args.len() - 1 - i
+                    ));
+                }
+
+                // if GLOBAL_METHODS.contains_key(name.name.as_str()) {
+                //     code.push(format!("\tcall {}",
+                // GLOBAL_METHODS[name.name.as_str()])); } else
+                if self.symbols.contains(&name.name) {
+                    // Call local function
+                    code.push(format!("\tcall {}", name));
+                } else if let Some(ns) = name.namespace.clone()
+                    && self.imports.contains_key(&ns)
+                {
+                    code.push(format!("\tcall {}", name));
+                } else {
+                    return Err(CompilerError::Undefined(name.clone()));
+                }
+
+                let result_reg: String;
+
+                if use_result {
+                    let (temp_result_reg, result_alloc) = self.allocator.alloc_temp()?;
+                    result_reg = temp_result_reg;
+
+                    code.extend(result_alloc);
+                    code.push(format!("\tpop {}", result_reg));
+
+                    // Clean up arguments
+                    if args.len() > 1 {
+                        for _ in 0..(args.len() - 1) {
+                            code.push("\tpop zero".to_string());
+                        }
+                    }
+                } else {
+                    result_reg = "zero".to_string();
+
+                    // Clean up arguments
+                    if args.len() > 0 {
+                        for _ in 0..(args.len()) {
+                            code.push("\tpop zero".to_string());
+                        }
+                    }
+                }
+
+                // Restore caller-saved registers in reverse order (LIFO)
+                // for reg in saved_regs.iter().rev() {
+                //     code.push(format!("\tpop {}", reg));
+                // }
+
+                // Free argument registers
+                for reg in arg_regs {
+                    self.allocator.free_temp(&reg);
+                }
+
+                Ok((result_reg, code))
+            }
+
+            Expression::Unary { op, operand } => {
+                let (operand_reg, operand_code) =
+                    self.generate_expression(operand, true)?;
+                code.extend(operand_code);
+
+                let (result_reg, result_alloc) = self.allocator.alloc_temp()?;
+                code.extend(result_alloc);
+
+                match op {
+                    UnaryOperator::Minus => {
+                        // Negate: result = 0 - operand
+                        code.push(format!("\tsub zero, {}, {}", operand_reg, result_reg));
+                    }
+                    UnaryOperator::Plus => {
+                        // Just move
+                        code.push(format!("\tmov {}, {}", operand_reg, result_reg));
+                    }
+                    UnaryOperator::Dereference => {
+                        code.push(format!("\tldw {}, {}", operand_reg, result_reg));
+                    }
+                    UnaryOperator::Reference => {
+                        code.extend(self.allocator.spill_register(&operand_reg)?);
+                        code.push(format!(
+                            "\tsubi bpr {} {}",
+                            -(4 + self.allocator.get_stack_offset()),
+                            result_reg
+                        ))
+                    }
+                }
+
+                self.allocator.free_temp(&operand_reg);
+                Ok((result_reg, code))
+            }
+
+            Expression::Empty => Ok(("zero".to_string(), code)),
+        }
+    }
+
+    // Helper for generating unique labels
+    fn get_unique_label(&mut self) -> String {
+        // You'd implement a counter here
+        static COUNTER: AtomicU32 = AtomicU32::new(0);
+
+        let val = COUNTER.fetch_add(1, std::sync::atomic::Ordering::SeqCst);
+        (val + 1).to_string()
+    }
+}
+
+/// Build a single string from any number of arguments.
+/// Each argument must implement `Display` or be convertible to a string.
+#[macro_export]
+macro_rules! dsa {
+    ($($arg:expr),* $(,)?) => {{
+        // Start with an empty String – we’ll grow it as we go.
+        use std::fmt::Write;
+        let mut s = ::std::string::String::new();
+        $(
+            // `write!` is cheaper than `format!` for each element
+            // because it re‑uses the same buffer.
+
+            write!(s, "{}\n", $arg).expect("write to String failed");
+        )*
+        s
+    }};
+}
+
+// ────────────────────────  dsa!  ────────────────────────
+// A tiny helper that just turns its token‑stream into a string.
+// The trailing comma is kept – it’s part of the syntax you want.
+#[macro_export]
+macro_rules! cmd {
+    ($($tokens:tt)*) => {{
+        // We’ll just stringify the tokens and return a String.
+        format!("{}", concat!(stringify!($tokens), "\n"))
+    }};
+}
+
+// ────────────────────────  block!  ────────────────────────
+// Usage:
+//
+//   let asm = block![ "name"
+//       dsa![mov rg0, rg1],
+//       dsa![add rg1, rg1]
+//   ];
+//
+// `asm` is a `&'static str` containing:
+//
+//   name:
+//       mov rg0, rg1
+//       add rg1, rg1
+//
+#[macro_export]
+macro_rules! block {
+    // The first token must be a string literal – that’s the label.
+    ($label:literal $(dsa![$($ins:tt)*]),* ) => {{
+        // Build a single string at compile time.
+        const CODE: &str = concat!(
+            $label, ":\n",
+            // Each `dsa!` call yields a string like `"mov rg0, rg1"`.
+            // We add a newline after each one to get the desired layout.
+            $(concat!("\t", stringify!($($ins)*), "\n")),*
+        );
+        CODE
+    }};
+}
+
+#[macro_export]
+macro_rules! comment {
+    ($text:expr) => {{ format!("// {}", $text) }};
+}

compiler/src/backend/dsa/mod.rs

@@ -0,0 +1,9 @@
+use crate::model::{CompilerError, Program};
+
+mod codegen;
+mod registers;
+
+pub fn generate_code(ast: &Program) -> Result<String, CompilerError> {
+    let mut codegen = codegen::CodeGenerator::new(ast.clone());
+    codegen.generate()
+}

compiler/src/backend/dsa/registers.rs

@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use crate::parser::CompilerError;
+use crate::model::CompilerError;
 
 /// Register allocator for DSA assembly generation
 /// Manages general-purpose registers (rg0-rgf) and handles stack spilling
@@ -147,7 +147,7 @@ impl RegisterAllocator {
     }
 
     /// Get the current location of a variable
-    pub fn get_var_location(&self, var_name: &str) -> Option<&Location> {
+    pub fn _get_var_location(&self, var_name: &str) -> Option<&Location> {
         self.variable_locations.get(var_name)
     }
 
@@ -264,7 +264,7 @@ impl RegisterAllocator {
     }
 
     /// Spill all registers to stack (useful before function calls)
-    pub fn spill_all(&mut self) -> Vec<String> {
+    pub fn _spill_all(&mut self) -> Vec<String> {
         let mut code = Vec::new();
 
         let regs_to_spill: Vec<String> = self.register_contents.keys().cloned().collect();
@@ -284,7 +284,7 @@ impl RegisterAllocator {
     }
 
     /// Get the total stack space needed for local variables
-    pub fn get_stack_size(&self) -> i32 {
+    pub fn _get_stack_size(&self) -> i32 {
         -self.stack_offset // Convert negative offset to positive size
     }
 
@@ -298,7 +298,7 @@ impl RegisterAllocator {
 
     /// Mark a variable as dead (no longer needed)
     /// Frees its register if it's in one
-    pub fn free_var(&mut self, var_name: &str) {
+    pub fn _free_var(&mut self, var_name: &str) {
         if let Some(Location::Register(reg)) = self.variable_locations.get(var_name) {
             let reg = reg.clone();
             self.register_contents.remove(&reg);
@@ -319,12 +319,12 @@ impl RegisterAllocator {
 
     /// Save caller-saved registers before a function call
     /// Returns assembly code to save them
-    pub fn save_caller_saved(&mut self) -> Vec<String> {
+    pub fn _save_caller_saved(&mut self) -> Vec<String> {
         let mut code = Vec::new();
 
         // For simplicity, save all currently used registers
         // In a more sophisticated compiler, you'd only save registers that are live
-        for (reg, var_name) in self.register_contents.clone() {
+        for (reg, _) in self.register_contents.clone() {
             if *self.in_use.get(&reg).unwrap_or(&false) {
                 code.push(format!("\tpush {}", reg));
             }
@@ -335,7 +335,7 @@ impl RegisterAllocator {
 
     /// Restore caller-saved registers after a function call
     /// Returns assembly code to restore them
-    pub fn restore_caller_saved(&mut self, saved_regs: &[String]) -> Vec<String> {
+    pub fn _restore_caller_saved(&mut self, saved_regs: &[String]) -> Vec<String> {
         let mut code = Vec::new();
 
         // Restore in reverse order (LIFO)
@@ -346,53 +346,3 @@ impl RegisterAllocator {
         code
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_basic_allocation() {
-        let mut allocator = RegisterAllocator::new();
-
-        let (reg1, code1) = allocator.alloc_temp().unwrap();
-        assert_eq!(code1.len(), 0); // No spill needed
-        assert_eq!(reg1, "rg0");
-
-        let (reg2, code2) = allocator.alloc_temp().unwrap();
-        assert_eq!(code2.len(), 0);
-        assert_eq!(reg2, "rg1");
-
-        allocator.free_temp(&reg1);
-
-        let (reg3, code3) = allocator.alloc_temp().unwrap();
-        assert_eq!(code3.len(), 0);
-        assert_eq!(reg3, "rg0"); // Reuses freed register
-    }
-
-    #[test]
-    fn test_variable_allocation() {
-        let mut allocator = RegisterAllocator::new();
-
-        let (reg, _) = allocator.alloc_var("x").unwrap();
-        assert_eq!(reg, "rg0");
-
-        // Requesting same variable again should return same register
-        let (reg2, _) = allocator.alloc_var("x").unwrap();
-        assert_eq!(reg2, "rg0");
-    }
-
-    #[test]
-    fn test_stack_allocation() {
-        let mut allocator = RegisterAllocator::new();
-
-        // Allocate all 16 registers
-        for i in 0..16 {
-            allocator.alloc_var(&format!("var{}", i)).unwrap();
-        }
-
-        // Next allocation should spill to stack
-        let (reg, code) = allocator.alloc_var("var16").unwrap();
-        assert!(code.len() > 0); // Should have spill code
-    }
-}

compiler/src/backend/mod.rs

@@ -0,0 +1,13 @@
+use crate::model::{CompilerError, Program};
+
+mod dsa;
+
+pub fn compiler_backend(ext: &str, ast: &Program) -> Result<String, CompilerError> {
+    match ext {
+        "dsa" => Ok(dsa::generate_code(ast)?),
+        _ => Err(CompilerError::Generic(format!(
+            "File type {} not supported",
+            ext
+        ))),
+    }
+}

compiler/src/frontend/dsc/lexer.rs

@@ -0,0 +1,627 @@
+use std::iter::Peekable;
+use std::str::Chars;
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Token {
+    // Keywords
+    Fn,
+    Let,
+    If,
+    Else,
+    Loop,
+    While,
+    Break,
+    Return,
+    Continue,
+    Include,
+    Static,
+    Const,
+
+    // Identifiers and literals
+    Identifier(Name),
+    String(String),
+    Integer(u64),
+    Char(char),
+
+    // Symbols
+    LeftParen,  // (
+    RightParen, // )
+    LeftBrace,  // {
+    RightBrace, // }
+    Semicolon,  // ;
+    Colon,      // :
+    Comma,      // ,
+
+    // Operators
+    Plus,         // +
+    Minus,        // -
+    Star,         // *
+    Amphersand,   // &
+    Slash,        // /
+    Assign,       // =
+    EqualEqual,   // ==
+    Bang,         // !
+    BangEqual,    // !=
+    Less,         // <
+    LessEqual,    // <=
+    Greater,      // >
+    GreaterEqual, // >=
+    RightArrow,   // ->
+
+    // Special
+    Eof,
+}
+
+use std::fmt;
+
+use crate::model::Name;
+
+impl fmt::Display for Name {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if let Some(ref ns) = self.namespace {
+            write!(f, "{}::{}", ns, self.name)
+        } else {
+            write!(f, "{}", self.name)
+        }
+    }
+}
+
+impl Token {
+    pub fn tt(&self) -> &str {
+        match self {
+            Token::Const => "Const",
+            Token::Static => "Static",
+            Token::Include => "Include",
+            Token::Fn => "Fn",
+            Token::If => "If",
+            Token::Let => "Let",
+            Token::Else => "Else",
+            Token::Loop => "Loop",
+            Token::While => "While",
+            Token::Break => "Break",
+            Token::Return => "Return",
+            Token::Continue => "Continue",
+            Token::Identifier(_) => "Identifier",
+            Token::String(_) => "String",
+            Token::Integer(_) => "UnsignedInt",
+            Token::Char(_) => "Char",
+            Token::LeftParen => "LeftParen",
+            Token::RightParen => "RightParen",
+            Token::LeftBrace => "LeftBrace",
+            Token::RightBrace => "RightBrace",
+            Token::Semicolon => "Semicolon",
+            Token::Colon => "Colon",
+            Token::Comma => "Comma",
+            Token::RightArrow => "RightArrow",
+            Token::Plus => "Plus",
+            Token::Minus => "Minus",
+            Token::Star => "Star",
+            Token::Amphersand => "Amphersand",
+            Token::Slash => "Slash",
+            Token::Assign => "Assign",
+            Token::EqualEqual => "EqualEqual",
+            Token::Bang => "Bang",
+            Token::BangEqual => "BangEqual",
+            Token::Less => "Less",
+            Token::LessEqual => "LessEqual",
+            Token::Greater => "Greater",
+            Token::GreaterEqual => "GreaterEqual",
+            Token::Eof => "Eof",
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct Lexer<'a> {
+    chars: Peekable<Chars<'a>>,
+    current: Option<char>,
+    line: usize,
+}
+
+impl<'a> Lexer<'a> {
+    pub fn new(input: &'a str) -> Self {
+        let mut chars = input.chars().peekable();
+        let current = chars.next();
+
+        Lexer {
+            chars,
+            current,
+            line: 1,
+        }
+    }
+
+    fn advance(&mut self) -> Option<char> {
+        self.current = self.chars.next();
+        self.current
+    }
+
+    fn peek(&mut self) -> Option<&char> {
+        self.chars.peek()
+    }
+
+    fn skip_whitespace(&mut self) {
+        while let Some(c) = self.current {
+            if !c.is_whitespace() {
+                break;
+            }
+            if c == '\n' {
+                self.line += 1;
+            }
+            self.advance();
+        }
+    }
+
+    fn skip_line_comment(&mut self) {
+        // Skip the two slashes
+        self.advance(); // first /
+        self.advance(); // second /
+
+        // Skip until newline or EOF
+        while let Some(c) = self.current {
+            if c == '\n' {
+                self.line += 1;
+                self.advance();
+                break;
+            }
+            self.advance();
+        }
+    }
+
+    fn skip_block_comment(&mut self) -> Result<(), String> {
+        // Skip the /*
+        self.advance(); // /
+        self.advance(); // *
+
+        let start_line = self.line;
+
+        // Look for */
+        while let Some(c) = self.current {
+            if c == '\n' {
+                self.line += 1;
+            }
+
+            if c == '*' {
+                if let Some(&next) = self.peek() {
+                    if next == '/' {
+                        self.advance(); // *
+                        self.advance(); // /
+                        return Ok(());
+                    }
+                }
+            }
+
+            self.advance();
+        }
+
+        Err(format!(
+            "Unterminated block comment starting at line {}",
+            start_line
+        ))
+    }
+
+    fn skip_whitespace_and_comments(&mut self) {
+        loop {
+            self.skip_whitespace();
+
+            // Check for comments
+            if let Some('/') = self.current {
+                if let Some(&next) = self.peek() {
+                    match next {
+                        '/' => {
+                            self.skip_line_comment();
+                            continue;
+                        }
+                        '*' => {
+                            if let Err(e) = self.skip_block_comment() {
+                                eprintln!("Lexer error: {}", e);
+                            }
+                            continue;
+                        }
+                        _ => break,
+                    }
+                }
+            }
+
+            break;
+        }
+    }
+
+    fn read_identifier(&mut self) -> String {
+        let mut ident = String::new();
+
+        // Include the current character if it's valid
+        if let Some(c) = self.current {
+            if c.is_alphabetic() || c == '_' {
+                ident.push(c);
+            }
+        }
+
+        // Read remaining characters
+        while let Some(&c) = self.peek() {
+            if c.is_alphanumeric() || c == '_' {
+                self.advance();
+                ident.push(c);
+            } else {
+                break;
+            }
+        }
+
+        ident
+    }
+
+    fn keyword_or_identifier(&mut self) -> Token {
+        let first_ident = self.read_identifier();
+
+        // Check if it's a keyword first (keywords can't have namespaces)
+        let keyword = match first_ident.as_str() {
+            "fn" => Some(Token::Fn),
+            "if" => Some(Token::If),
+            "else" => Some(Token::Else),
+            "while" => Some(Token::While),
+            "loop" => Some(Token::Loop),
+            "break" => Some(Token::Break),
+            "return" => Some(Token::Return),
+            "continue" => Some(Token::Continue),
+            "include" => Some(Token::Include),
+            "let" => Some(Token::Let),
+            "const" => Some(Token::Const),
+            "static" => Some(Token::Static),
+            _ => None,
+        };
+
+        if let Some(kw) = keyword {
+            return kw;
+        }
+
+        // Not a keyword - check for namespace separator (::)
+        // We need to peek TWO characters ahead without consuming anything
+        if let Some(&':') = self.peek() {
+            // We see one colon, but we need to check if there's another one after it
+            // We can't peek two ahead directly, so we need a different approach
+
+            // Save the current position by using a temporary peekable iterator
+            // Actually, we can't do that easily. Instead, let's just check:
+            // If we see ':', temporarily advance and check the next char
+
+            // Create a temporary check
+            let mut temp_chars = self.chars.clone();
+            let _ = temp_chars.next(); // This is the ':' we already saw
+            let second_peek = temp_chars.peek();
+
+            if let Some(&':') = second_peek {
+                // It's :: - consume both colons
+                self.advance(); // consume first :
+                self.advance(); // consume second :
+
+                // Read the second identifier (the actual name)
+                let second_ident = self.read_identifier();
+
+                // Return namespaced identifier
+                return Token::Identifier(Name {
+                    namespace: Some(first_ident),
+                    name: second_ident,
+                });
+            }
+            // else: It's a single colon (type annotation) - DON'T consume it
+            // Just fall through and return the identifier
+        }
+
+        // No namespace separator - just a regular identifier
+        Token::Identifier(Name {
+            namespace: None,
+            name: first_ident,
+        })
+    }
+
+    fn read_number(&mut self) -> Result<u64, String> {
+        let current = self.current.unwrap();
+
+        // Check for hex (0x) or binary (0b) prefix
+        if current == '0' {
+            if let Some(&next_char) = self.peek() {
+                match next_char {
+                    'x' | 'X' => {
+                        self.advance(); // consume '0'
+                        self.advance(); // consume 'x'
+                        return self.read_hex_number();
+                    }
+                    'b' | 'B' => {
+                        self.advance(); // consume '0'
+                        self.advance(); // consume 'b'
+                        return self.read_binary_number();
+                    }
+                    _ => {}
+                }
+            }
+        }
+
+        // Read decimal number
+        self.read_decimal_number()
+    }
+
+    fn read_decimal_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        if let Some(c) = self.current {
+            num_str.push(c);
+        }
+
+        while let Some(&c) = self.peek() {
+            if c.is_ascii_digit() {
+                self.advance();
+                num_str.push(c);
+            } else {
+                break;
+            }
+        }
+
+        num_str
+            .parse::<u64>()
+            .map_err(|_| format!("Invalid decimal number: {}", num_str))
+    }
+
+    fn read_hex_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        // Read current character if it's a hex digit
+        if let Some(c) = self.current {
+            if c.is_ascii_hexdigit() {
+                num_str.push(c);
+            }
+        }
+
+        while let Some(&c) = self.peek() {
+            if c.is_ascii_hexdigit() {
+                self.advance();
+                num_str.push(c);
+            } else {
+                break;
+            }
+        }
+
+        if num_str.is_empty() {
+            return Err("Invalid hexadecimal number: no digits after 0x".to_string());
+        }
+
+        u64::from_str_radix(&num_str, 16)
+            .map_err(|_| format!("Invalid hexadecimal number: {}", num_str))
+    }
+
+    fn read_binary_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        // Read current character if it's a binary digit
+        if let Some(c) = self.current {
+            if c == '0' || c == '1' {
+                num_str.push(c);
+            }
+        }
+
+        while let Some(&c) = self.peek() {
+            if c == '0' || c == '1' {
+                self.advance();
+                num_str.push(c);
+            } else {
+                break;
+            }
+        }
+
+        if num_str.is_empty() {
+            return Err("Invalid binary number: no digits after 0b".to_string());
+        }
+
+        u64::from_str_radix(&num_str, 2)
+            .map_err(|_| format!("Invalid binary number: {}", num_str))
+    }
+
+    fn read_string(&mut self) -> Result<String, String> {
+        self.advance(); // Skip the opening quote
+        let mut s = String::new();
+
+        while let Some(c) = self.current {
+            if c == '"' {
+                return Ok(s);
+            }
+
+            // Handle escape sequences
+            if c == '\\' {
+                self.advance();
+                if let Some(escaped) = self.current {
+                    let escaped_char = match escaped {
+                        'n' => '\n',
+                        't' => '\t',
+                        'r' => '\r',
+                        '\\' => '\\',
+                        '"' => '"',
+                        _ => escaped, // For now, just use the character as-is
+                    };
+                    s.push(escaped_char);
+                } else {
+                    return Err("Unexpected end of string after escape".to_string());
+                }
+            } else {
+                s.push(c);
+            }
+
+            self.advance();
+        }
+
+        Err("Unterminated string literal".to_string())
+    }
+
+    fn match_next(&mut self, expected: char) -> bool {
+        match self.peek() {
+            Some(&c) if c == expected => {
+                self.advance();
+                true
+            }
+            _ => false,
+        }
+    }
+
+    fn scan_single_char_token(&mut self, c: char) -> Option<Token> {
+        match c {
+            '(' => Some(Token::LeftParen),
+            ')' => Some(Token::RightParen),
+            '{' => Some(Token::LeftBrace),
+            '}' => Some(Token::RightBrace),
+            ';' => Some(Token::Semicolon),
+            ',' => Some(Token::Comma),
+            '&' => Some(Token::Amphersand),
+            '+' => Some(Token::Plus),
+            '*' => Some(Token::Star),
+            _ => None,
+        }
+    }
+
+    fn scan_operator(&mut self, c: char) -> Option<Token> {
+        match c {
+            '-' => Some(if self.match_next('>') {
+                Token::RightArrow
+            } else {
+                Token::Minus
+            }),
+            '!' => Some(if self.match_next('=') {
+                Token::BangEqual
+            } else {
+                Token::Bang
+            }),
+            '=' => Some(if self.match_next('=') {
+                Token::EqualEqual
+            } else {
+                Token::Assign
+            }),
+            '<' => Some(if self.match_next('=') {
+                Token::LessEqual
+            } else {
+                Token::Less
+            }),
+            '>' => Some(if self.match_next('=') {
+                Token::GreaterEqual
+            } else {
+                Token::Greater
+            }),
+            ':' => {
+                // Single colon (for type annotations)
+                // Note: :: is handled in keyword_or_identifier for namespaces
+                Some(Token::Colon)
+            }
+            '/' => {
+                // Check if it's a comment or division
+                if let Some(&next) = self.peek() {
+                    if next == '/' || next == '*' {
+                        // It's a comment, don't consume it here
+                        // Let skip_whitespace_and_comments handle it
+                        None
+                    } else {
+                        Some(Token::Slash)
+                    }
+                } else {
+                    Some(Token::Slash)
+                }
+            }
+            _ => None,
+        }
+    }
+
+    pub fn next_token(&mut self) -> Token {
+        self.skip_whitespace_and_comments();
+
+        let Some(c) = self.current else {
+            return Token::Eof;
+        };
+
+        // Try single-character tokens first
+        if let Some(token) = self.scan_single_char_token(c) {
+            self.advance();
+            return token;
+        }
+
+        // Try operators (may be multi-character)
+        if let Some(token) = self.scan_operator(c) {
+            self.advance();
+            return token;
+        }
+
+        // Char literals
+        if c == '\'' {
+            let mut value = ' ';
+            self.advance();
+            if let Some(ch) = self.current {
+                value = ch;
+                self.advance();
+            }
+            if self.current == Some('\'') {
+                self.advance();
+                return Token::Char(value);
+            }
+            eprintln!("Lexer error on line {}: Invalid char literal", self.line);
+        }
+
+        // String literals
+        if c == '"' {
+            let token = match self.read_string() {
+                Ok(s) => Token::String(s),
+                Err(e) => {
+                    eprintln!("Lexer error on line {}: {}", self.line, e);
+                    // Skip to next quote or end
+                    while let Some(ch) = self.current {
+                        if ch == '"' || ch == '\n' {
+                            break;
+                        }
+                        self.advance();
+                    }
+                    Token::String(String::new())
+                }
+            };
+            self.advance();
+            return token;
+        }
+
+        // Identifiers and keywords (including namespaced identifiers)
+        if c.is_alphabetic() || c == '_' {
+            let token = self.keyword_or_identifier();
+            self.advance();
+            return token;
+        }
+
+        // Numbers (decimal, hex, binary)
+        if c.is_ascii_digit() {
+            let token = match self.read_number() {
+                Ok(num) => Token::Integer(num),
+                Err(e) => {
+                    eprintln!("Lexer error on line {}: {}", self.line, e);
+                    // Skip invalid number
+                    while let Some(&ch) = self.peek() {
+                        if !ch.is_alphanumeric() {
+                            break;
+                        }
+                        self.advance();
+                    }
+                    Token::Integer(0)
+                }
+            };
+            self.advance();
+            return token;
+        }
+
+        // Unknown character - skip it
+        eprintln!(
+            "Lexer warning on line {}: Skipping unknown character '{}'",
+            self.line, c
+        );
+        self.advance();
+        self.next_token()
+    }
+}
+
+impl<'a> Iterator for Lexer<'a> {
+    type Item = Token;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self.next_token() {
+            Token::Eof => None,
+            token => Some(token),
+        }
+    }
+}

compiler/src/frontend/dsc/mod.rs

@@ -0,0 +1,38 @@
+use common::logging::log;
+
+use crate::model::{CompilerError, Program};
+use parser::{ParseResult, Parser};
+use semantic_analyser::Analyser;
+
+pub mod lexer;
+pub mod parser;
+pub mod semantic_analyser;
+
+pub fn generate_ast(input: &str) -> Result<Program, CompilerError> {
+    log("Tokenising Input...");
+
+    let lexer = lexer::Lexer::new(&input);
+    let tokens = lexer.collect::<Vec<_>>();
+    // println!("{tokens:?}");
+
+    log(&format!("Parsing {} Tokens...", tokens.len()));
+
+    let mut parser = Parser::new(tokens);
+    let ast = match parser.parse() {
+        ParseResult::Accept(ast) => ast,
+        ParseResult::Reject(e) => return Err(e),
+        ParseResult::Deny => {
+            return Err(CompilerError::Generic("Parser used ::Deny".to_string()));
+        }
+    };
+    // println!("{ast:#?}");
+
+    log("Analyzing AST...");
+    log("Checking Type Information...");
+
+    let analyser = Analyser::new();
+    analyser.analyse(ast.clone()).unwrap();
+
+    log("Type Checking Complete...");
+    Ok(ast)
+}

compiler/src/frontend/dsc/parser.rs

@@ -1,6 +1,9 @@
-use crate::lexer::{Name, Token};
+use super::lexer::Token;
+use crate::model::{
+    BinaryOperator, Block, CompilerError, ConstExpr, Declaration, Dependency, Expression,
+    Program, Statement, TypeId, UnaryOperator, Variable,
+};
 use crate::{expect_tt, expect_value};
-use core::fmt;
 use std::ops::{ControlFlow, FromResidual, Try};
 
 #[derive(Debug, Clone)]
@@ -10,16 +13,6 @@ pub enum ParseResult<T, E> {
     Reject(E),
 }
 
-#[derive(Debug, Clone)]
-pub enum CompilerError {
-    UnexpectedToken(Token),
-    UnexpectedEndOfInput,
-    UnexpectedCharacter(char),
-    Undefined(Name),
-    InvalidSyntax(String),
-    Generic(String),
-}
-
 pub struct Parser {
     tokens: Vec<Token>,
     idx: usize,
@@ -86,7 +79,11 @@ impl Parser {
             let init = match value {
                 Token::String(x) => Some(ConstExpr::String(x)),
                 Token::Integer(x) => Some(ConstExpr::Number(x as i32)),
-                _ => return ParseResult::Reject(CompilerError::UnexpectedToken(value)),
+                _ => {
+                    return ParseResult::Reject(CompilerError::UnexpectedToken(
+                        value.tt().to_string(),
+                    ));
+                }
             };
 
             let _ = expect_tt!(self.next()?, Semicolon)?;
@@ -141,7 +138,9 @@ impl Parser {
                 body: self.parse_block()?,
             })
         } else {
-            ParseResult::Reject(CompilerError::UnexpectedToken(self.peek_next()?))
+            ParseResult::Reject(CompilerError::UnexpectedToken(
+                self.peek_next()?.tt().to_string(),
+            ))
         }
     }
 
@@ -268,7 +267,7 @@ impl Parser {
                 expr
             } else {
                 return ParseResult::Reject(CompilerError::UnexpectedToken(
-                    self.peek_next()?,
+                    self.peek_next()?.tt().to_string(),
                 ));
             };
 
@@ -341,7 +340,9 @@ impl Parser {
             });
         }
 
-        ParseResult::Reject(CompilerError::UnexpectedToken(self.peek_next()?))
+        ParseResult::Reject(CompilerError::UnexpectedToken(
+            self.peek_next()?.tt().to_string(),
+        ))
     }
 
     fn parse_expression(&mut self) -> ParseResult<Expression, CompilerError> {
@@ -463,7 +464,9 @@ impl Parser {
                 let _ = expect_tt!(self.next()?, RightParen)?;
                 ParseResult::Accept(expr)
             }
-            _ => ParseResult::Reject(CompilerError::UnexpectedToken(self.peek_next()?)),
+            _ => ParseResult::Reject(CompilerError::UnexpectedToken(
+                self.peek_next()?.tt().to_string(),
+            )),
         }
     }
 
@@ -525,197 +528,6 @@ impl Parser {
     }
 }
 
-#[derive(Debug, Clone)]
-pub struct Program {
-    pub declarations: Vec<Declaration>,
-}
-
-#[derive(Debug, Clone)]
-pub enum Declaration {
-    Function {
-        name: String,
-        return_type: TypeId,
-        params: Vec<Variable>,
-        body: Block,
-    },
-    Variable {
-        var: Variable,
-        init: Option<ConstExpr>,
-        is_const: bool,
-    },
-    Dependency(Dependency),
-}
-
-#[derive(Debug, Clone)]
-pub struct Dependency {
-    pub name: String,
-    pub path: String,
-}
-
-#[derive(Debug, Clone)]
-pub enum TypeId {
-    U8,
-    U16,
-    U32,
-    I8,
-    I16,
-    I32,
-    Char,
-    Void,
-    Ptr(Box<TypeId>),
-    Ref(Box<TypeId>),
-    Array(Box<TypeId>, usize),
-    Struct { name: Name, fields: Vec<Variable> },
-}
-
-pub type Block = Vec<Statement>;
-
-#[derive(Debug, Clone)]
-pub struct Variable {
-    pub name: String,
-    pub type_id: TypeId,
-}
-
-#[derive(Debug, Clone)]
-pub enum Statement {
-    Block(Block),
-    Declaration {
-        var: Variable,
-        value: Option<Expression>,
-    },
-    Assign {
-        varname: String,
-        value: Expression,
-    },
-    PtrWrite {
-        ptr: Expression,
-        value: Expression,
-    },
-    Expression {
-        expr: Expression,
-    },
-    If {
-        condition: Expression,
-        then_stmt: Block,
-        else_stmt: Block,
-    },
-    While {
-        condition: Expression,
-        body: Vec<Statement>,
-    },
-    Loop(Block),
-    Break,
-    Continue,
-    Return(Option<Expression>),
-}
-
-#[derive(Debug, Clone)]
-pub enum ConstExpr {
-    Number(i32),
-    String(String),
-}
-
-impl fmt::Display for ConstExpr {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            ConstExpr::Number(n) => write!(f, "{}", n),
-            ConstExpr::String(s) => write!(f, "\"{}\"", s),
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-pub enum Expression {
-    Empty,
-    Binary {
-        op: BinaryOperator,
-        left: Box<Expression>,
-        right: Box<Expression>,
-    },
-    Unary {
-        op: UnaryOperator,
-        operand: Box<Expression>,
-    },
-    Variable {
-        name: Name,
-        expr_type: Option<TypeId>,
-    },
-    Call {
-        name: Name,
-        args: Vec<Expression>,
-    },
-    Number(isize),
-    StringLiteral(String),
-    CharLiteral(char),
-}
-
-impl Expression {
-    pub fn is_pure(&self) -> bool {
-        match self {
-            Expression::Number(_) => true,
-            Expression::StringLiteral(_) => true,
-            Expression::CharLiteral(_) => true,
-            Expression::Call { name, args } => false, /* TODO: will require checking */
-            // if the associated function
-            // body is pure
-            Expression::Binary { left, right, .. } => left.is_pure() && right.is_pure(),
-            Expression::Unary { op, operand } => operand.is_pure(),
-            Expression::Empty => true,
-            Expression::Variable { name, expr_type } => true,
-        }
-    }
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum BinaryOperator {
-    Add,
-    Sub,
-    Mul,
-    Div,
-    Eq,
-    Ne,
-    Lt,
-    Gt,
-    Le,
-    Ge,
-}
-
-impl fmt::Display for BinaryOperator {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            BinaryOperator::Add => write!(f, "+"),
-            BinaryOperator::Sub => write!(f, "-"),
-            BinaryOperator::Mul => write!(f, "*"),
-            BinaryOperator::Div => write!(f, "/"),
-            BinaryOperator::Eq => write!(f, "=="),
-            BinaryOperator::Ne => write!(f, "!="),
-            BinaryOperator::Lt => write!(f, "<"),
-            BinaryOperator::Gt => write!(f, ">"),
-            BinaryOperator::Le => write!(f, "<="),
-            BinaryOperator::Ge => write!(f, ">="),
-        }
-    }
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum UnaryOperator {
-    Plus,
-    Minus,
-    Reference,
-    Dereference,
-}
-
-impl fmt::Display for UnaryOperator {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            UnaryOperator::Plus => write!(f, "+"),
-            UnaryOperator::Minus => write!(f, "-"),
-            UnaryOperator::Dereference => write!(f, "*"),
-            UnaryOperator::Reference => write!(f, "&"),
-        }
-    }
-}
-
 impl<T, E> ParseResult<T, E> {
     pub fn accepted(&self) -> bool {
         matches!(self, ParseResult::Accept(_))
@@ -772,7 +584,7 @@ macro_rules! expect_tt {
             )+
             _ => {
                 // let expected = format!("[{}]", vec![$(stringify!($variant)),+].join(" | "));
-                ParseResult::Reject(CompilerError::UnexpectedToken(token))
+                ParseResult::Reject(CompilerError::UnexpectedToken(tt))
             }
         }
     }};
@@ -784,7 +596,9 @@ macro_rules! expect_value {
         let tok = $expr;
         match tok.clone() {
             Token::$variant(value) => ParseResult::Accept(value),
-            _ => ParseResult::Reject(CompilerError::UnexpectedToken(tok)),
+            _ => {
+                ParseResult::Reject(CompilerError::UnexpectedToken(tok.tt().to_string()))
+            }
         }
     }};
 }

compiler/src/frontend/dsc/semantic_analyser.rs

@@ -0,0 +1,13 @@
+use crate::model::{CompilerError, Program};
+
+pub struct Analyser;
+
+impl Analyser {
+    pub fn new() -> Self {
+        Self
+    }
+
+    pub fn analyse(&self, _ast: Program) -> Result<(), CompilerError> {
+        Ok(())
+    }
+}

compiler/src/frontend/mod.rs

@@ -0,0 +1,15 @@
+use crate::model::{CompilerError, Program};
+
+mod c;
+mod dsc;
+
+pub fn compiler_frontend(ext: &str, data: &str) -> Result<Program, CompilerError> {
+    match ext {
+        "dsc" => Ok(dsc::generate_ast(&data)?),
+        "c" => Ok(c::generate_ast(&data)?),
+        _ => Err(CompilerError::Generic(format!(
+            "File type {} not supported",
+            ext
+        ))),
+    }
+}

compiler/src/lib.rs

@@ -4,17 +4,12 @@ use std::path::Path;
 
 use common::logging::log;
 
-use crate::{
-    codegen::CodeGenerator,
-    parser::{ParseResult, Parser},
-    semantic_analyser::Analyser,
-};
+use crate::specialised::build_specialised;
 
-mod codegen;
-mod lexer;
-mod parser;
-mod registers;
-mod semantic_analyser;
+mod backend;
+mod frontend;
+mod model;
+mod specialised;
 
 pub fn compile_file(
     input_path: &Path,
@@ -22,43 +17,44 @@ pub fn compile_file(
 ) -> Result<(), Box<dyn std::error::Error>> {
     let input = std::fs::read_to_string(input_path).expect("Failed to read input file");
 
-    log("Tokenising Input...");
+    let input_ext = input_path
+        .extension()
+        .and_then(|s| s.to_str())
+        .unwrap_or("");
 
-    let lexer = lexer::Lexer::new(&input);
-    let tokens = lexer.collect::<Vec<_>>();
-    // println!("{tokens:?}");
-
-    log(&format!("Parsing {} Tokens...", tokens.len()));
-
-    let mut parser = Parser::new(tokens);
-    let ast = match parser.parse() {
-        ParseResult::Accept(ast) => ast,
-        ParseResult::Reject(e) => {
-            eprintln!("Error: {e:?}");
-            return Err("Parsing error".into());
-        }
-        ParseResult::Deny => {
-            panic!("Parser denied parsing")
-        }
+    // check if we're using a specialised compiler
+    if let Some(output) = build_specialised(input_ext, &input) {
+        let result = match output {
+            Ok(output) => output,
+            Err(err) => return Err(format!("Compilation failed: {err:?}").into()),
         };
-    // println!("{ast:#?}");
 
-    log("Analyzing AST...");
-    log("Checking Type Information...");
+        std::fs::write(output_path, &result).expect("Failed to write output");
 
-    let analyser = Analyser::new();
-    analyser.analyse(ast.clone()).unwrap();
+        log(&format!(
+            "Compilation Successful ✅ \n\tSource: {}\n\tOutput: {}\n",
+            input_path.display(),
+            output_path.display(),
+        ));
 
-    log("Generating Code...");
-
-    // Code Gen
-    let mut generator = CodeGenerator::new(ast);
-    let result = match generator.generate() {
-        Ok(code) => code,
-        Err(e) => {
-            eprintln!("Parsing error: {:?}", e);
-            return Err("Code generation error".into());
+        return Ok(());
     }
+
+    // Parse the input using the frontend, providing the file extension and data.
+    let ast = match frontend::compiler_frontend(input_ext, &input) {
+        Ok(ast) => ast,
+        Err(err) => return Err(format!("Compilation failed: {err:?}").into()),
+    };
+
+    let output_ext = output_path
+        .extension()
+        .and_then(|s| s.to_str())
+        .unwrap_or("");
+
+    // Generate the output using the backend with the parsed result.
+    let result = match backend::compiler_backend(output_ext, &ast) {
+        Ok(result) => result,
+        Err(err) => return Err(format!("Compilation failed: {err:?}").into()),
     };
 
     // println!("{result}");

compiler/src/main.rs

@@ -6,7 +6,7 @@ fn main() {
     // read from input file: syntax "c_compiler <src.c> [output.dsa]"
     let args: Vec<String> = std::env::args().collect();
     if args.len() < 2 {
-        eprintln!("Usage: c_compiler <src.c> [output.dsa]");
+        eprintln!("Usage: c_compiler <src.dsc> [output.dsa]");
         return;
     }
 

compiler/src/model.rs

@@ -0,0 +1,213 @@
+use core::fmt;
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub enum CompilerError {
+    UnexpectedToken(String),
+    UnexpectedEndOfInput,
+    UnexpectedCharacter(char),
+    Undefined(Name),
+    InvalidSyntax(String),
+    Generic(String),
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct Name {
+    pub name: String,
+    pub namespace: Option<String>,
+}
+
+#[derive(Debug, Clone)]
+pub struct Program {
+    pub declarations: Vec<Declaration>,
+}
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub enum Declaration {
+    Function {
+        name: String,
+        return_type: TypeId,
+        params: Vec<Variable>,
+        body: Block,
+    },
+    Variable {
+        var: Variable,
+        init: Option<ConstExpr>,
+        is_const: bool,
+    },
+    Dependency(Dependency),
+}
+
+#[derive(Debug, Clone)]
+pub struct Dependency {
+    pub name: String,
+    pub path: String,
+}
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub enum TypeId {
+    U8,
+    U16,
+    U32,
+    I8,
+    I16,
+    I32,
+    Char,
+    Void,
+    Ptr(Box<TypeId>),
+    Ref(Box<TypeId>),
+    Array(Box<TypeId>, usize),
+    Struct { name: Name, fields: Vec<Variable> },
+}
+
+pub type Block = Vec<Statement>;
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub struct Variable {
+    pub name: String,
+    pub type_id: TypeId,
+}
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub enum Statement {
+    Block(Block),
+    Declaration {
+        var: Variable,
+        value: Option<Expression>,
+    },
+    Assign {
+        varname: String,
+        value: Expression,
+    },
+    PtrWrite {
+        ptr: Expression,
+        value: Expression,
+    },
+    Expression {
+        expr: Expression,
+    },
+    If {
+        condition: Expression,
+        then_stmt: Block,
+        else_stmt: Block,
+    },
+    While {
+        condition: Expression,
+        body: Vec<Statement>,
+    },
+    Loop(Block),
+    Break,
+    Continue,
+    Return(Option<Expression>),
+}
+
+#[derive(Debug, Clone)]
+pub enum ConstExpr {
+    Number(i32),
+    String(String),
+}
+
+impl fmt::Display for ConstExpr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            ConstExpr::Number(n) => write!(f, "{}", n),
+            ConstExpr::String(s) => write!(f, "\"{}\"", s),
+        }
+    }
+}
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+pub enum Expression {
+    Empty,
+    Binary {
+        op: BinaryOperator,
+        left: Box<Expression>,
+        right: Box<Expression>,
+    },
+    Unary {
+        op: UnaryOperator,
+        operand: Box<Expression>,
+    },
+    Variable {
+        name: Name,
+        expr_type: Option<TypeId>,
+    },
+    Call {
+        name: Name,
+        args: Vec<Expression>,
+    },
+    Number(isize),
+    StringLiteral(String),
+    CharLiteral(char),
+}
+
+impl Expression {
+    pub fn is_pure(&self) -> bool {
+        match self {
+            Expression::Number(_) => true,
+            Expression::StringLiteral(_) => true,
+            Expression::CharLiteral(_) => true,
+            Expression::Call { .. } => false,
+            Expression::Binary { left, right, .. } => left.is_pure() && right.is_pure(),
+            Expression::Unary { operand, .. } => operand.is_pure(),
+            Expression::Empty => true,
+            Expression::Variable { .. } => true,
+        }
+    }
+}
+
+#[allow(unused)]
+#[derive(Debug, Clone, PartialEq)]
+pub enum BinaryOperator {
+    Add,
+    Sub,
+    Mul,
+    Div,
+    Eq,
+    Ne,
+    Lt,
+    Gt,
+    Le,
+    Ge,
+}
+
+impl fmt::Display for BinaryOperator {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            BinaryOperator::Add => write!(f, "+"),
+            BinaryOperator::Sub => write!(f, "-"),
+            BinaryOperator::Mul => write!(f, "*"),
+            BinaryOperator::Div => write!(f, "/"),
+            BinaryOperator::Eq => write!(f, "=="),
+            BinaryOperator::Ne => write!(f, "!="),
+            BinaryOperator::Lt => write!(f, "<"),
+            BinaryOperator::Gt => write!(f, ">"),
+            BinaryOperator::Le => write!(f, "<="),
+            BinaryOperator::Ge => write!(f, ">="),
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum UnaryOperator {
+    Plus,
+    Minus,
+    Reference,
+    Dereference,
+}
+
+impl fmt::Display for UnaryOperator {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            UnaryOperator::Plus => write!(f, "+"),
+            UnaryOperator::Minus => write!(f, "-"),
+            UnaryOperator::Dereference => write!(f, "*"),
+            UnaryOperator::Reference => write!(f, "&"),
+        }
+    }
+}

compiler/src/semantic_analyser.rs

@@ -1,13 +0,0 @@
-use crate::parser::{CompilerError, Program};
-
-pub struct Analyser;
-
-impl Analyser {
-    pub fn new() -> Self {
-        Self
-    }
-
-    pub fn analyse(&self, ast: Program) -> Result<(), CompilerError> {
-        Ok(())
-    }
-}