Use stack of blocks

2026-07-27 13:11:59 -07:00 · 2025-07-18 00:43:22 -05:00
parent f18920fd33
commit 15b050a343
2 changed files with 38 additions and 12 deletions
@@ -20,7 +20,9 @@ partial class Decompiler
    {
        var methodBody = _context.GetMethodBody(startOffset);

-        List<StatementSyntax> topStatements = [];
+        Stack<BlockSyntax> blockStack = [];
+        blockStack.Push(Block());
+
        Stack<object> stack = new();

        for (int i = 0; i < methodBody.Length; i++)
@@ -48,7 +50,7 @@ partial class Decompiler
                    case OpCode.ConstructObject:
                        var typeToCtor = _context.GetImportedType(instruction.Operands.First());
                        stack.Push(ObjectCreationExpression(
-                            IdentifierName(_context.GetQualifiedName(typeToCtor).ToString()),
+                            IrisExpression.ToSyntax(typeToCtor, _context),
                            ArgumentList(),
                            null
                        ));
@@ -56,21 +58,22 @@ partial class Decompiler

                    case OpCode.LookupSymbol:
                        var symbolIndex = (ushort)instruction.Operands.First().Value;
-                        stack.Push(IdentifierName(export.SymbolReferenceTable[symbolIndex].Symbol));
+                        stack.Push(IrisExpression.ToSyntax(export.SymbolReferenceTable[symbolIndex]));
                        break;

                    case OpCode.WriteSymbol:
                    case OpCode.WriteSymbolPeek:
                        var writeSymbolIndex = (ushort)instruction.Operands.First().Value;
-                        var writeSymbolExpr = IdentifierName(export.SymbolReferenceTable[writeSymbolIndex].Symbol);

                        var newSymbolValue = opCode is OpCode.WriteSymbolPeek
                            ? stack.Peek() : stack.Pop();

                        var symbolAssignmentExpr = AssignmentExpression(SyntaxKind.SimpleAssignmentExpression,
-                            writeSymbolExpr, IrisExpression.ToSyntax(newSymbolValue, _context));
+                            IrisExpression.ToSyntax(export.SymbolReferenceTable[writeSymbolIndex]),
+                            IrisExpression.ToSyntax(newSymbolValue, _context)
+                        );

-                        topStatements.Add(ExpressionStatement(symbolAssignmentExpr));
+                        AddStatementToBlock(blockStack, ExpressionStatement(symbolAssignmentExpr));
                        break;

                    case OpCode.MethodInvoke:
@@ -102,7 +105,8 @@ partial class Decompiler

                        var methodExpression = MemberAccessExpression(SyntaxKind.SimpleMemberAccessExpression,
                            IrisExpression.ToSyntax(targetObj, _context),
-                            IdentifierName(methodSchema.Name));
+                            IdentifierName(methodSchema.Name)
+                        );

                        var methodResult = InvocationExpression(methodExpression, ArgumentList([.. parameters]));

@@ -112,7 +116,7 @@ partial class Decompiler
                        }
                        else
                        {
-                            topStatements.Add(ExpressionStatement(methodResult));
+                            AddStatementToBlock(blockStack, ExpressionStatement(methodResult));
                        }

                        if (pushLastParam)
@@ -135,7 +139,8 @@ partial class Decompiler

                        var propertyGetExpression = MemberAccessExpression(SyntaxKind.SimpleMemberAccessExpression,
                            IrisExpression.ToSyntax(propTarget, _context),
-                            IdentifierName(propToGet.Name));
+                            IdentifierName(propToGet.Name)
+                        );

                        stack.Push(propertyGetExpression);
                        break;
@@ -180,9 +185,17 @@ partial class Decompiler
            }
        }

+        if (blockStack.Count > 1)
+            throw new InvalidOperationException($"Failed to decompile script for {export.Name}, more than one top-level code block");
+        else if (blockStack.Count < 0)
+            throw new InvalidOperationException($"Failed to decompile script for {export.Name}, no top-level code blocks");
+
+        // Unwrap top-most block to avoid extra curly braces around entire script
+        var topBlock = blockStack.Pop();
+
        return SyntaxTree(
            CompilationUnit().WithMembers(
-                [..topStatements.Select(GlobalStatement)]
+                [..topBlock.Statements.Select(GlobalStatement)]
            )
        );
    }
@@ -196,4 +209,11 @@ partial class Decompiler
            .GetText(token)
            .ToString();
    }
+
+    private static void AddStatementToBlock(Stack<BlockSyntax> blockStack, StatementSyntax statement)
+    {
+        var block = blockStack.Pop();
+        block = block.AddStatements(statement);
+        blockStack.Push(block);
+    }
 }
@@ -46,8 +46,8 @@ internal abstract class IrisExpression : Expression
            IStringEncodable strEnc => ParseExpression(strEnc.EncodeString()),

            Disassembler.RawConstantInfo constantInfo => new IrisConstantExpression(constantInfo.Value, constantInfo.Type).ToSyntax(context),
-            SymbolReference symbolRef => IdentifierName(symbolRef.Symbol),
-            TypeSchema typeSchema => IdentifierName(context.GetQualifiedName(typeSchema).ToString()),
+            SymbolReference symbolRef => ToSyntax(symbolRef),
+            TypeSchema typeSchema => ToSyntax(typeSchema, context),

            IrisExpression irisExpr => irisExpr.ToSyntax(context),
            Expression expr => ParseExpression(expr.ToString()),
@@ -56,4 +56,10 @@ internal abstract class IrisExpression : Expression
            _ => IdentifierName(obj.ToString())
        };
    }
+
+    public static IdentifierNameSyntax ToSyntax(TypeSchema type, DecompileContext context) =>
+        IdentifierName(context.GetQualifiedName(type).ToString());
+
+    public static IdentifierNameSyntax ToSyntax(SymbolReference symbolRef) =>
+        IdentifierName(symbolRef.Symbol);
 }