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Diffstat (limited to 'Compiler/visitors/Definitions.cs')
| -rw-r--r-- | Compiler/visitors/Definitions.cs | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/Compiler/visitors/Definitions.cs b/Compiler/visitors/Definitions.cs new file mode 100644 index 0000000..e4cf797 --- /dev/null +++ b/Compiler/visitors/Definitions.cs @@ -0,0 +1,123 @@ +namespace Q1.Compiler.visitors; + +public partial class CCompilerVisitor +{ + private List<(CGrammarParser.FunctionDefinitionContext context, + FunctionReference function, FunctionOverload overload, + List<string> paramNames, List<CType> paramTypes)> _functionBodies = new(); + + private VariableReference FindVariable(string varName) + { + foreach (Dictionary<string, VariableReference> variables in this._variableStack) + { + if (variables.TryGetValue(varName, out VariableReference? reference)) + return reference; + } + + throw new CompilerException($"Variable {varName} could not be found in current scope."); + } + private int Alloc(int size) + { + int loc = CCompilerVisitor._memPointer; + CCompilerVisitor._memPointer += size; + + return loc; + } + private FunctionReference CreateOrGetFunctionReference(string name, CType type) + { + FunctionReference? function = this._methods.FirstOrDefault(x => x.Name == name); + if (function != null) + return function; + + function = new FunctionReference(name, type); + this._methods.Add(function); + + return function; + } + private FunctionReference GetFunctionReference(string name) + { + FunctionReference? function = this._methods.FirstOrDefault(x => x.Name == name); + if (function != null) + return function; + + throw new CompilerException($"Function '{name}' has not been defined or prototyped."); + } + + public override string? VisitFunctionPrototype(CGrammarParser.FunctionPrototypeContext context) + { + string functionName = context.name.Text; + CType type = this.VisitCType(context._type); + + List<CType> parameterTypes = context._types.Select(this.VisitCType).ToList(); + List<string> parameterNames = context._params.Select(x => x.Text).ToList(); + + FunctionReference function = this.CreateOrGetFunctionReference(functionName, type); + FunctionOverload overload = function.CreateOverloadWithoutBody(parameterNames, parameterTypes); + + function.Overloads.Add(overload); + + return null; + } + public override string? VisitFunctionDefinition(CGrammarParser.FunctionDefinitionContext context) + { + string functionName = context.name.Text; + CType type = this.VisitCType(context.rtype); + + List<CType> paramTypes = context._types.Select(this.VisitCType).ToList(); + List<string> paramNames = context._params.Select(x => x.Text).ToList(); + + FunctionReference function = this.CreateOrGetFunctionReference(functionName, type); + FunctionOverload overload = function.CreateOverloadWithBody(paramNames, paramTypes); + + this._functionBodies.Add((context, function, overload, paramNames, paramTypes)); + + return null; + } + private void VisitFunctionBody(CGrammarParser.FunctionDefinitionContext context, FunctionReference function, FunctionOverload overload, List<string> paramNames, List<CType> paramTypes) + { + this.Branch(function.GetBranchName(overload), function.GetBranchFriendlyName(overload)); + + if (paramNames.Count > 0) + this.Instruction("pop V0", "preserve function return address"); + + Dictionary<string, VariableReference> scope = this.EnterScope(); + foreach ((string paramName, CType paramType) in paramNames.Zip(paramTypes)) + { + int addr = this.Alloc(paramType.Size); + scope[paramName] = new(addr, paramType); + this.Instruction($"pop [${addr:X4}]", $"param {paramType} {paramName}"); + } + + if (paramNames.Count > 0) + this.Instruction("push V0", "restore function return address"); + + this.VisitChildren(context); + this.ExitScope(); + + this.Instruction("mov 0, V0", "fallback return 0"); + this.Instruction("ret"); + this.Blank(); + } + public override string? VisitVariableDeclaration(CGrammarParser.VariableDeclarationContext context) + { + CType type = this.VisitCType(context.type()); + int addr = this.Alloc(CType.Int.Size); + string name = context.name.Text; + + Dictionary<string, VariableReference> scope = this._variableStack.Peek(); + if (scope.ContainsKey(name)) + throw new CompilerException($"Variable {name} already exists in current scope."); + + scope[name] = new VariableReference(addr, type); + string initialValue = "0"; + + if (context.value != null) + { + initialValue = this.VisitExpression(context.value); + } + + this.DynamicMove(CType.Int, initialValue, $"[${addr:X4}]", $"int {name} = {initialValue}"); + + return null; + } +}
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