...

Nub.Lang/Nub.Lang/Generation/Generator.cs

@@ -0,0 +1,272 @@
+using System.Text;
+using Nub.Lang.Parsing;
+
+namespace Nub.Lang.Generation;
+
+public class Generator
+{
+    private const string Entrypoint = "main";
+    
+    private readonly IReadOnlyCollection<DefinitionNode> _definitions;
+    private readonly SymbolTable _symbolTable;
+    private readonly StringBuilder _builder;
+    private Dictionary<string, string> _strings;
+    private int _stringIndex;
+    
+    public Generator(IReadOnlyCollection<DefinitionNode> definitions)
+    {
+        _strings = [];
+        _definitions = definitions;
+        _builder = new StringBuilder();
+        _symbolTable = new SymbolTable(definitions.OfType<GlobalVariableDefinitionNode>().ToList());
+        foreach (var funcDefinitionNode in definitions.OfType<FuncDefinitionNode>())
+        {
+            _symbolTable.DefineFunc(funcDefinitionNode);
+        }
+    }
+
+    public string Generate()
+    {
+        _builder.AppendLine("global _start");
+        
+        _builder.AppendLine();
+        _builder.AppendLine("section .bss");
+        foreach (var globalVariable in _definitions.OfType<GlobalVariableDefinitionNode>())
+        {
+            var symbol = _symbolTable.ResolveGlobalVariable(globalVariable.Name);
+            _builder.AppendLine($"    {symbol.Identifier}: resq 1");
+        }
+
+        _builder.AppendLine();
+        _builder.AppendLine("section .text");
+        _builder.AppendLine("_start:");
+        
+        var main = _symbolTable.ResolveFunc(Entrypoint, []);
+        
+        foreach (var globalVariable in _definitions.OfType<GlobalVariableDefinitionNode>())
+        {
+            var symbol = _symbolTable.ResolveGlobalVariable(globalVariable.Name);
+            _builder.AppendLine($"    ; Initialize global variable {symbol.Name}");
+            GenerateExpression(globalVariable.Value, main);
+            _builder.AppendLine($"    mov [{symbol.Identifier}], rax");
+        }
+
+        _builder.AppendLine();
+        _builder.AppendLine($"    ; Call entrypoint {Entrypoint}");
+        _builder.AppendLine($"    call {main.Label}");
+
+        _builder.AppendLine();
+        _builder.AppendLine("    ; Exit with status code 0");
+        _builder.AppendLine("    mov rax, 60");
+        _builder.AppendLine("    mov rdi, 0");
+        _builder.AppendLine("    syscall");
+
+        foreach (var funcDefinition in _definitions.OfType<FuncDefinitionNode>())
+        {
+            _builder.AppendLine();
+            GenerateFuncDefinition(funcDefinition);
+        }
+        _builder.AppendLine();
+        _builder.AppendLine("section .data");
+        foreach (var str in _strings)
+        {
+            _builder.AppendLine($"{str.Key}: db `{str.Value}`, 0");
+        }
+        
+        return _builder.ToString();
+    }
+
+    private void GenerateFuncDefinition(FuncDefinitionNode funcDefinition)
+    {
+        var symbol = _symbolTable.ResolveFunc(funcDefinition.Name, funcDefinition.Parameters.Select(p => p.Type).ToList());
+        _builder.AppendLine($"; {funcDefinition.ToString()}");
+        _builder.AppendLine($"{symbol.Label}:");
+        _builder.AppendLine("    push rbp");
+        _builder.AppendLine("    mov rbp, rsp");
+        _builder.AppendLine($"    sub rsp, {symbol.StackAllocation}");
+        
+        string[] registers = ["rdi", "rsi", "rdx", "rcx", "r8", "r9"];
+        
+        for (var i = 0; i < symbol.Parameters.Count; i++)
+        {
+            var parameter = symbol.Parameters.ElementAt(i);
+
+            if (i < registers.Length)
+            {
+                var variable = symbol.ResolveLocalVariable(parameter.Name);
+                _builder.AppendLine($"    mov [rbp - {variable.Offset}], {registers[i]}");
+            }
+            else
+            {
+                // TODO: Implement parameters passed on the stack
+                throw new NotImplementedException();
+            }
+        }
+        
+        GenerateBlock(funcDefinition.Body, symbol);
+        _builder.AppendLine("    mov rsp, rbp");
+        _builder.AppendLine("    pop rbp");
+        _builder.AppendLine("    ret");
+    }
+
+    private void GenerateBlock(BlockNode block, Func func)
+    {
+        foreach (var statement in block.Statements)
+        {
+            GenerateStatement(statement, func);
+        }
+    }
+
+    private void GenerateStatement(StatementNode statement, Func func)
+    {
+        switch (statement)
+        {
+            case FuncCallStatementNode funcCallStatement:
+                GenerateFuncCall(funcCallStatement.FuncCall, func);
+                break;
+            case SyscallStatementNode syscallStatement:
+                GenerateSyscall(syscallStatement.Syscall, func);
+                break;
+            case VariableAssignmentNode variableAssignment:
+                throw new NotImplementedException();
+                break;
+            default:
+                throw new ArgumentOutOfRangeException(nameof(statement));
+        }
+    }
+
+    private void GenerateExpression(ExpressionNode expression, Func func)
+    {
+        switch (expression)
+        {
+            case FuncCallExpressionNode funcCallExpression:
+                throw new NotImplementedException();
+                break;
+            case IdentifierNode identifier:
+                GenerateIdentifier(identifier, func);
+                break;
+            case LiteralNode literal:
+                GenerateLiteral(literal, func);
+                break;
+            case SyscallExpressionNode syscallExpression:
+                throw new NotImplementedException();
+                break;
+            default:
+                throw new ArgumentOutOfRangeException(nameof(expression));
+        }
+    }
+
+    private void GenerateIdentifier(IdentifierNode identifier, Func func)
+    {
+        var variable = func.ResolveVariable(identifier.Identifier);
+
+        switch (variable)
+        {
+            case GlobalVariable globalVariable:
+                _builder.AppendLine($"    mov rax, [{globalVariable.Identifier}]");
+                break;
+            case LocalVariable localVariable:
+            {
+                _builder.AppendLine($"    mov rax, [rbp - {localVariable.Offset}]");
+                break;
+            }
+            default:
+            {
+                throw new ArgumentOutOfRangeException(nameof(variable));
+            }
+        }
+    }
+
+    private void GenerateLiteral(LiteralNode literal, Func func)
+    {
+        switch (literal.Type)
+        {
+            case DelegateType:
+                throw new NotImplementedException();
+                break;
+            case StringType:
+                var ident = $"string{++_stringIndex}";
+                _strings.Add(ident, literal.Literal);
+                _builder.AppendLine($"    mov rax, {ident}");
+                break;
+            case PrimitiveType primitive:
+                switch (primitive.Kind)
+                {
+                    case PrimitiveTypeKind.Bool:
+                    {
+                        var value = literal.Literal == "true" ? 1 : 0;
+                        _builder.AppendLine($"    mov al, {value}");
+                        break;
+                    }
+                    case PrimitiveTypeKind.Char:
+                        throw new NotImplementedException();
+                        break;
+                    case PrimitiveTypeKind.Int8:
+                    case PrimitiveTypeKind.UInt8:
+                        _builder.AppendLine($"    mov al, {literal.Literal}");
+                        break;
+                    case PrimitiveTypeKind.Int16:
+                    case PrimitiveTypeKind.UInt16:
+                        _builder.AppendLine($"    mov ax, {literal.Literal}");
+                        break;
+                    case PrimitiveTypeKind.Int32:
+                    case PrimitiveTypeKind.UInt32:
+                        _builder.AppendLine($"    mov eax, {literal.Literal}");
+                        break;
+                    case PrimitiveTypeKind.Int64:
+                    case PrimitiveTypeKind.UInt64:
+                        _builder.AppendLine($"    mov rax, {literal.Literal}");
+                        break;
+                    case PrimitiveTypeKind.Float:
+                        throw new NotImplementedException();
+                        break;
+                    case PrimitiveTypeKind.Double:
+                        throw new NotImplementedException();
+                        break;
+                    default:
+                        throw new ArgumentOutOfRangeException();
+                }
+                break;
+            default:
+                throw new ArgumentOutOfRangeException();
+        }
+    }
+
+    // TODO: Use stack for more than 6 parameters
+    private void GenerateFuncCall(FuncCall funcCall, Func func)
+    {
+        var symbol = _symbolTable.ResolveFunc(funcCall.Name, funcCall.Parameters.Select(p => p.Type).ToList());
+        string[] registers = ["rdi", "rsi", "rdx", "rcx", "r8", "r9"];
+
+        foreach (var parameter in funcCall.Parameters)
+        {
+            GenerateExpression(parameter, func);
+            _builder.AppendLine("    push rax");
+        }
+        
+        for (var i = funcCall.Parameters.Count - 1; i >= 0; i--)
+        {
+            _builder.AppendLine($"    pop {registers[i]}");
+        }
+        
+        _builder.AppendLine($"    call {symbol.Label}");
+    }
+
+    private void GenerateSyscall(Syscall syscall, Func func)
+    {
+        string[] registers = ["rax", "rdi", "rsi", "rdx", "r10", "r8", "r9"];
+
+        foreach (var parameter in syscall.Parameters)
+        {
+            GenerateExpression(parameter, func);
+            _builder.AppendLine("    push rax");
+        }
+                
+        for (var i = syscall.Parameters.Count - 1; i >= 0; i--)
+        {
+            _builder.AppendLine($"    pop {registers[i]}");
+        }
+                
+        _builder.AppendLine("    syscall");
+    }
+}

Nub.Lang/Nub.Lang/Generation/SymbolTable.cs

@@ -0,0 +1,128 @@
+using Nub.Lang.Parsing;
+using Nub.Lib;
+
+namespace Nub.Lang.Generation;
+
+public class SymbolTable
+{
+    private readonly List<Func> _functions = [];
+    private readonly List<GlobalVariable> _globalVariables = [];
+    private int _labelIndex;
+
+    public SymbolTable(IReadOnlyCollection<GlobalVariableDefinitionNode> globalVariableDefinitions)
+    {
+        var globalVariableIndex = 0;
+        foreach (var globalVariable in globalVariableDefinitions)
+        {
+            var identifier = $"variable{++globalVariableIndex}";
+            _globalVariables.Add(new GlobalVariable(globalVariable.Name, globalVariable.Value.Type, identifier));
+        }
+    }
+    
+    public void DefineFunc(FuncDefinitionNode funcDefinition)
+    {
+        var label = $"func{++_labelIndex}";
+        var localVariables = ResolveFunctionVariables(funcDefinition);
+        _functions.Add(new Func(label, funcDefinition.Name, funcDefinition.Parameters, funcDefinition.ReturnType, _globalVariables.Concat<Variable>(localVariables.Variables).ToList(), localVariables.StackSize));
+    }
+
+    private (int StackSize, List<LocalVariable> Variables) ResolveFunctionVariables(FuncDefinitionNode funcDefinition)
+    {
+        var offset = 0;
+        List<LocalVariable> variables = [];
+
+        foreach (var parameter in funcDefinition.Parameters)
+        {
+            offset += 8;
+            variables.Add(new LocalVariable(parameter.Name, parameter.Type, offset));
+        }
+        
+        foreach (var statement in funcDefinition.Body.Statements)
+        {
+            if (statement is VariableAssignmentNode variableAssignment)
+            {
+                offset += 8;
+                variables.Add(new LocalVariable(variableAssignment.Name, variableAssignment.Value.Type, offset));
+            }
+        }
+
+        return (offset, variables);
+    }
+    
+    public Func ResolveFunc(string name, IReadOnlyCollection<Type> parameterTypes)
+    {
+        var func = _functions.FirstOrDefault(f => f.Name == name && f.Parameters.Count == parameterTypes.Count && f.Parameters.Where((p, i) => p.Type == parameterTypes.ElementAt(i)).Count() == parameterTypes.Count);
+        if (func == null)
+        {
+            throw new Exception($"Func {name}({string.Join(", ", parameterTypes)}) is not defined");
+        }
+
+        return func;
+    }
+    
+    public GlobalVariable ResolveGlobalVariable(string name)
+    {
+        var variable = _globalVariables.FirstOrDefault(v => v.Name == name);
+        if (variable == null)
+        {
+            throw new Exception($"Global variable {name} is not defined");
+        }
+
+        return variable;
+    }
+}
+
+public abstract class Variable(string name, Type type)
+{
+    public string Name { get; } = name;
+    public Type Type { get; } = type;
+}
+
+public class LocalVariable(string name, Type type, int offset) : Variable(name, type)
+{
+    public int Offset { get; } = offset;
+}
+
+public class GlobalVariable(string name, Type type, string identifier) : Variable(name, type)
+{
+    public string Identifier { get; } = identifier;
+}
+
+public class Func(string label, string name, IReadOnlyCollection<FuncParameter> parameters, Optional<Type> returnType, IReadOnlyCollection<Variable> variables, int stackAllocation)
+{
+    public string Label { get; } = label;
+    public string Name { get; } = name;
+    public IReadOnlyCollection<FuncParameter> Parameters { get; } = parameters;
+    public Optional<Type> ReturnType { get; } = returnType;
+    public IReadOnlyCollection<Variable> Variables { get; } = variables;
+    public int StackAllocation { get; } = stackAllocation;
+
+    public Variable ResolveVariable(string name)
+    {
+        var variable = Variables.FirstOrDefault(v => v.Name == name);
+        if (variable == null)
+        {
+            throw new Exception($"Variable {name} is not defined");
+        }
+
+        return variable;
+    }
+    
+    public LocalVariable ResolveLocalVariable(string name)
+    {
+        var variable = Variables.FirstOrDefault(v => v.Name == name);
+        if (variable == null)
+        {
+            throw new Exception($"Variable {name} is not defined");
+        }
+
+        if (variable is not LocalVariable localVariable)
+        {
+            throw new Exception($"Variable {name} is not a local variable");
+        }
+
+        return localVariable;
+    }
+    
+    public override string ToString() => $"{Name}({string.Join(", ", Parameters.Select(p => p.ToString()))}){(ReturnType.HasValue ? ": " + ReturnType.Value : "")}";
+}

Nub.Lang/Nub.Lang/Input/program.nub

@@ -4,9 +4,9 @@ let STD_OUT = 1;
 let STD_ERR = 2;
 
 func main() {
-    write("test");
+    write("test\n");
 }
 
-func write(msg: Func) {
-    syscall(SYS_WRITE, STD_OUT, msg);
+func write(msg: pointer) {
+    syscall(SYS_WRITE, STD_OUT, msg, 5);
 }

Nub.Lang/Nub.Lang/Lexing/Lexer.cs

@@ -104,7 +104,7 @@ public class Lexer
                 buffer += current.Value;
             }
             
-            return new LiteralToken(new PointerType(), buffer);
+            return new LiteralToken(new StringType(), buffer);
         }
 
         if (char.IsWhiteSpace(current.Value))

Nub.Lang/Nub.Lang/Output/run.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+nasm -g -felf64 out.asm -o out.o
+ld out.o -o out
+./out
+
+rm out.o
+
+echo "Process exited with status code $?"

Nub.Lang/Nub.Lang/Parsing/BlockNode.cs

@@ -1,6 +1,6 @@
 namespace Nub.Lang.Parsing;
 
-public class BlockNode(IEnumerable<StatementNode> statements) : Node
+public class BlockNode(IReadOnlyCollection<StatementNode> statements) : Node
 {
-    public IEnumerable<StatementNode> Statements { get; } = statements;
+    public IReadOnlyCollection<StatementNode> Statements { get; } = statements;
 }

Nub.Lang/Nub.Lang/Parsing/FuncCall.cs

@@ -1,9 +1,9 @@
 namespace Nub.Lang.Parsing;
 
-public class FuncCall(string name, IEnumerable<ExpressionNode> parameters)
+public class FuncCall(string name, IReadOnlyCollection<ExpressionNode> parameters)
 {
     public string Name { get; } = name;
-    public IEnumerable<ExpressionNode> Parameters { get; } = parameters;
+    public IReadOnlyCollection<ExpressionNode> Parameters { get; } = parameters;
 
     public override string ToString() => $"{Name}()";
 }

Nub.Lang/Nub.Lang/Parsing/FuncDefinitionNode.cs

@@ -2,12 +2,12 @@
 
 namespace Nub.Lang.Parsing;
 
-public class FuncDefinitionNode(string name, IEnumerable<FuncParameter> parameters, BlockNode body, Optional<Type> returnType) : DefinitionNode
+public class FuncDefinitionNode(string name, IReadOnlyCollection<FuncParameter> parameters, BlockNode body, Optional<Type> returnType) : DefinitionNode
 {
     public string Name { get; } = name;
-    public IEnumerable<FuncParameter> Parameters { get; } = parameters;
+    public IReadOnlyCollection<FuncParameter> Parameters { get; } = parameters;
     public BlockNode Body { get; } = body;
     public Optional<Type> ReturnType { get; } = returnType;
 
-    public override string ToString() => $"{Name}({Parameters.Select(p => p.ToString())}){(ReturnType.HasValue ? ": " + ReturnType.Value : "")}";
+    public override string ToString() => $"{Name}({string.Join(", ", Parameters.Select(p => p.ToString()))}){(ReturnType.HasValue ? ": " + ReturnType.Value : "")}";
 }

Nub.Lang/Nub.Lang/Parsing/Parser.cs

@@ -8,7 +8,7 @@ public class Parser
     private readonly Token[] _tokens;
     private int _index;
 
-    public Parser(IEnumerable<Token> tokens)
+    public Parser(IReadOnlyCollection<Token> tokens)
     {
         _tokens = tokens.ToArray();
     }
@@ -181,7 +181,12 @@ public class Parser
 
             var returnType = Optional<Type>.OfNullable(typeArguments.LastOrDefault());
 
-            return new DelegateType(typeArguments.Take(typeArguments.Count - 1), returnType);
+            return new DelegateType(typeArguments.Take(typeArguments.Count - 1).ToList(), returnType);
+        }
+
+        if (name == "pointer")
+        {
+            return new StringType();
         }
 
         return PrimitiveType.Parse(name);

Nub.Lang/Nub.Lang/Parsing/Syscall.cs

@@ -1,6 +1,6 @@
 namespace Nub.Lang.Parsing;
 
-public class Syscall(IEnumerable<ExpressionNode> parameters)
+public class Syscall(IReadOnlyCollection<ExpressionNode> parameters)
 {
-    public IEnumerable<ExpressionNode> Parameters { get; } = parameters;
+    public IReadOnlyCollection<ExpressionNode> Parameters { get; } = parameters;
 }

Nub.Lang/Nub.Lang/Program.cs

@@ -1,4 +1,5 @@
-using Nub.Lang.Lexing;
+using Nub.Lang.Generation;
+using Nub.Lang.Lexing;
 using Nub.Lang.Parsing;
 using Nub.Lang.Typing;
 
@@ -11,4 +12,11 @@ var parser = new Parser(tokens);
 var definitions = parser.Parse();
 
 var typer = new ExpressionTyper(definitions);
-typer.Populate();
+typer.Populate();
+
+var generator = new Generator(definitions);
+var asm = generator.Generate();
+
+Console.WriteLine(asm);
+
+File.WriteAllText(args[1], asm);

Nub.Lang/Nub.Lang/Type.cs

@@ -2,10 +2,15 @@
 
 namespace Nub.Lang;
 
-public abstract class Type;
+public abstract record Type;
 
-public class PrimitiveType(PrimitiveTypeKind kind) : Type
+public record PrimitiveType : Type
 {
+    public PrimitiveType(PrimitiveTypeKind kind)
+    {
+        Kind = kind;
+    }
+    
     public static PrimitiveType Parse(string value)
     {
         var kind = value switch
@@ -28,7 +33,9 @@ public class PrimitiveType(PrimitiveTypeKind kind) : Type
         return new PrimitiveType(kind);
     }
     
-    public PrimitiveTypeKind Kind { get; } = kind;
+    public PrimitiveTypeKind Kind { get; }
+
+    public override string ToString() => Kind.ToString();
 }
 
 public enum PrimitiveTypeKind
@@ -47,10 +54,21 @@ public enum PrimitiveTypeKind
     Double,
 }
 
-public class PointerType : Type;
-
-public class DelegateType(IEnumerable<Type> parameters, Optional<Type> returnType) : Type
+public record StringType : Type
 {
-    public IEnumerable<Type> Parameters { get; } = parameters;
-    public Optional<Type> ReturnType { get; } = returnType;
+    public override string ToString() => "string";
+}
+
+public record DelegateType : Type
+{
+    public DelegateType(IReadOnlyCollection<Type> parameters, Optional<Type> returnType)
+    {
+        Parameters = parameters;
+        ReturnType = returnType;
+    }
+    
+    public IReadOnlyCollection<Type> Parameters { get; }
+    public Optional<Type> ReturnType { get; }
+
+    public override string ToString() => $"({string.Join(", ", Parameters)}): {(ReturnType.HasValue ? ReturnType.Value.ToString() : "")}";
 }