public AssignStatement(SymbolReference target, Expression value,
SourcePosition start, SourcePosition end)
: base(ASTNodeType.AssignStatement, start, end)
{
Target = target;
Value = value;
}
public Expression DecompileNativeFunction(UInt16 index)
{
var parameters = new List<Expression>();
while (!CurrentIs(StandardByteCodes.EndFunctionParms))
{
var param = DecompileExpression();
if (param == null)
return null; // ERROR
parameters.Add(param);
}
PopByte();
var entry = NativeTable[index];
Expression call = null;
switch (entry.Type)
{
case NativeType.Function:
var func = new SymbolReference(null, null, null, entry.Name);
call = new FunctionCall(func, parameters, null, null);
break;
case NativeType.Operator: // TODO: table should hold precedence, currently all have 0 and it'll be a mess.
var op = new InOpDeclaration(entry.Name, entry.Precedence, false, null, null, null, null, null, null, null);
call = new InOpReference(op, parameters[0], parameters[1], null, null);
break;
case NativeType.PreOperator: // TODO: table should hold precedence, currently all have 0 and it'll be a mess.
var preOp = new PreOpDeclaration(entry.Name, false, null, null, null, null, null, null);
call = new PreOpReference(preOp, parameters[0], null, null);
break;
case NativeType.PostOperator: // TODO: table should hold precedence, currently all have 0 and it'll be a mess.
var postOp = new PostOpDeclaration(entry.Name, false, null, null, null, null, null, null);
call = new PostOpReference(postOp, parameters[0], null, null);
break;
}
StartPositions.Pop();
return call;
}
public Expression DecompileGoW_DefaultValue()
{
PopByte();
var unkn = ReadByte();
var expr = DecompileExpression();
StartPositions.Pop();
var op = new InOpDeclaration("", 0, true, null, null, null, null, null, null, null);
var objRef = new SymbolReference(null, null, null, "UNSUPPORTED: GoW_DefaultValue: Byte:" + unkn + " - ");
return new InOpReference(op, objRef, expr, null, null);
}
public Expression DecompileFunctionCall(bool byName = false, bool withUnknShort = false, bool global = false)
{
PopByte();
String funcName;
if (byName)
{
funcName = PCC.GetName(ReadNameRef());
}
else
{
var funcObj = ReadObject();
funcName = funcObj.ObjectName;
if (funcName == DataContainer.Name && !isInClassContext) // If we're calling ourself, it's a super call
{
var str = "super";
var currentClass = DataContainer.ExportEntry.GetOuterOfType("Class").Object as ME3Class;
var funcOuterClass = funcObj.GetOuterOfType("Class").ObjectName;
if (currentClass != null && currentClass.SuperField != null && currentClass.SuperField.Name == funcOuterClass)
funcName = str + "." + funcName;
else
funcName = str + "(" + funcOuterClass + ")." + funcName;
}
}
if (global)
funcName = "global." + funcName;
if (withUnknShort)
ReadInt16(); // TODO: related to unkn65, split out? Possibly jump?
var parameters = new List<Expression>();
while (!CurrentIs(StandardByteCodes.EndFunctionParms))
{
if (CurrentIs(StandardByteCodes.Nothing))
{
PopByte(); // TODO: is this reasonable? what does it mean?
parameters.Add(new SymbolReference(null, null, null, "None"));
continue;
}
var param = DecompileExpression();
if (param == null)
return null; // ERROR
parameters.Add(param);
}
PopByte();
StartPositions.Pop();
var func = new SymbolReference(null, null, null, funcName);
return new FunctionCall(func, parameters, null, null);
}
// TODO: only skips one object? see code.
public Expression DecompileEatReturn()
{
PopByte();
var obj = ReadObject();
var expr = DecompileExpression();
StartPositions.Pop();
var op = new InOpDeclaration("", 0, true, null, null, null, null, null, null, null);
var objRef = new SymbolReference(null, null, null, "UNSUPPORTED: EatReturnValue: " + obj.ObjectName + "|" + obj.ClassName + " -");
return new InOpReference(op, objRef, expr, null, null);
}
public Expression DecompileContext(bool isClass = false)
{
PopByte();
var left = DecompileExpression();
if (left == null)
return null; // ERROR
ReadInt16(); // discard MemSize value. (size of expr-right in half-bytes)
ReadObject(); // discard RetValRef.
ReadByte(); // discard unknown byte.
isInClassContext = isClass;
var right = DecompileExpression();
if (right == null)
return null; // ERROR
isInClassContext = false;
if (isClass)
{
var builder = new CodeBuilderVisitor(); // what a wonderful hack, TODO.
left.AcceptVisitor(builder);
var str = builder.GetCodeString() + ".static";
left = new SymbolReference(null, null, null, str);
}
StartPositions.Pop();
return new CompositeSymbolRef(left, right, null, null);
}
public FunctionCall(SymbolReference func, List <Expression> arguments, SourcePosition start, SourcePosition end)
: base(ASTNodeType.FunctionCall, start, end)
{
Function = func;
Arguments = arguments;
}
public FunctionCall(SymbolReference func, List<Expression> parameters, SourcePosition start, SourcePosition end)
: base(ASTNodeType.FunctionCall, start, end)
{
Function = func;
Parameters = parameters;
}
public bool VisitNode(SymbolReference node)
{
// symbolname
Append("{0}", node.Name);
return true;
}
// TODO: guess for loop, probably requires a large restructure
public Statement DecompileConditionalJump(bool isOpt = false)
{
PopByte();
var scopeStartOffset = StartPositions.Pop();
Statement statement = null;
bool hasElse = false;
var scopeStatements = new List<Statement>();
UInt16 scopeEndJmpOffset = 0;
UInt16 afterScopeOffset = 0;
Expression conditional = null;
if (isOpt)
{
var obj = ReadObject();
var optCheck = Convert.ToBoolean(ReadByte());
afterScopeOffset = ReadUInt16();
String special = (optCheck ? "" : "!") + obj.ObjectName;
conditional = new SymbolReference(null, null, null, special);
}
else
{
afterScopeOffset = ReadUInt16();
conditional = DecompileExpression();
}
if (conditional == null)
return null;
if (afterScopeOffset < scopeStartOffset) // end of do_until detection
{
scopeStartOffset = afterScopeOffset;
var outerScope = Scopes[CurrentScope.Peek()];
var startStatement = StatementLocations[afterScopeOffset];
StatementLocations.Remove(afterScopeOffset);
var index = outerScope.IndexOf(startStatement);
scopeStatements = new List<Statement>(outerScope.Skip(index));
outerScope.RemoveRange(index, outerScope.Count - index);
statement = new DoUntilLoop(conditional, new CodeBody(scopeStatements, null, null), null, null);
}
Scopes.Add(scopeStatements);
CurrentScope.Push(Scopes.Count - 1);
while (Position < afterScopeOffset)
{
if (CurrentIs(StandardByteCodes.Jump))
{
var contPos = (UInt16)Position;
PopByte();
scopeEndJmpOffset = ReadUInt16();
if (scopeEndJmpOffset == scopeStartOffset)
{
statement = new WhileLoop(conditional, new CodeBody(scopeStatements, null, null), null, null);
break;
}
else if (Position < afterScopeOffset) // if we are not at the end of the scope, this is a continue statement in a loop rather than an else statement
{
var cont = new ContinueStatement(null, null);
StatementLocations.Add(contPos, cont);
scopeStatements.Add(cont);
}
else if (ForEachScopes.Count != 0 && scopeEndJmpOffset == ForEachScopes.Peek())
{
var breakStatement = new BreakStatement(null, null);
StatementLocations.Add(contPos, breakStatement);
scopeStatements.Add(breakStatement);
}
else
{
hasElse = true;
}
continue;
}
var current = DecompileStatement();
if (current == null)
return null; // ERROR ?
scopeStatements.Add(current);
}
CurrentScope.Pop();
List<Statement> elseStatements = new List<Statement>();
if (hasElse)
{
var endElseOffset = scopeEndJmpOffset;
Scopes.Add(elseStatements);
CurrentScope.Push(Scopes.Count - 1);
while (Position < endElseOffset)
{
var current = DecompileStatement();
if (current == null)
return null; // ERROR ?
elseStatements.Add(current);
}
CurrentScope.Pop();
}
statement = statement ?? new IfStatement(conditional, new CodeBody(scopeStatements, null, null),
null, null, elseStatements.Count != 0 ? new CodeBody(elseStatements, null, null) : null);
StatementLocations.Add(scopeStartOffset, statement);
return statement;
}
public Statement DecompileStatement()
{
StartPositions.Push((UInt16)Position);
var token = CurrentByte;
switch (token)
{
// return [expression];
case (byte)StandardByteCodes.Return:
return DecompileReturn();
// switch (expression)
case (byte)StandardByteCodes.Switch:
return DecompileSwitch();
// case expression :
case (byte)StandardByteCodes.Case:
return DecompileCase();
// if (expression) // while / for / do until
case (byte)StandardByteCodes.JumpIfNot:
return DecompileConditionalJump();
// continue
case (byte)StandardByteCodes.Jump: // TODO: UDK seems to compile this from break when inside ForEach, handle?
return DecompileJump();
// continue (iterator)
case (byte)StandardByteCodes.IteratorNext:
PopByte(); // pop iteratornext token
return DecompileJump();
// break;
case (byte)StandardByteCodes.IteratorPop:
return DecompileIteratorPop();
// stop;
case (byte)StandardByteCodes.Stop:
PopByte();
var stopStatement = new StopStatement(null, null);
StatementLocations.Add(StartPositions.Pop(), stopStatement);
return stopStatement;
// Goto label
case (byte)StandardByteCodes.GotoLabel:
PopByte();
var labelExpr = DecompileExpression();
var func = new SymbolReference(null, null, null, "goto");
var call = new FunctionCall(func, new List<Expression>() { labelExpr }, null, null);
var gotoLabel = new ExpressionOnlyStatement(null, null, call);
StatementLocations.Add(StartPositions.Pop(), gotoLabel);
return gotoLabel;
// assignable expression = expression;
case (byte)StandardByteCodes.Let:
case (byte)StandardByteCodes.LetBool:
case (byte)StandardByteCodes.LetDelegate:
return DecompileAssign();
// [skip x bytes]
case (byte)StandardByteCodes.Skip: // TODO: this should never occur as statement, possibly remove?
PopByte();
ReadUInt16();
StartPositions.Pop();
return DecompileStatement();
case (byte)StandardByteCodes.Nothing:
PopByte();
StartPositions.Pop();
return DecompileStatement(); // TODO, should probably have a nothing expression or statement, this is ugly
// foreach IteratorFunction(...)
case (byte)StandardByteCodes.Iterator:
return DecompileForEach();
// foreach arrayName(valuevariable[, indexvariable])
case (byte)StandardByteCodes.DynArrayIterator:
return DecompileForEach(isDynArray: true);
case (byte)StandardByteCodes.LabelTable:
DecompileLabelTable();
StartPositions.Pop();
return DecompileStatement();
#region unsupported
case (byte)StandardByteCodes.OptIfLocal: // TODO: verify, handle syntax
return DecompileConditionalJump(isOpt: true);
case (byte)StandardByteCodes.OptIfInstance: // TODO: verify, handle syntax
return DecompileConditionalJump(isOpt: true);
#endregion
default:
var expr = DecompileExpression();
if (expr != null)
{
var statement = new ExpressionOnlyStatement(null, null, expr);
StatementLocations.Add(StartPositions.Pop(), statement);
return statement;
}
// ERROR!
break;
}
return null;
}
public ReturnStatement DecompileReturn()
{
PopByte();
Expression expr = null;
if (CurrentIs(StandardByteCodes.ReturnNullValue))
{
// TODO: research this a bit, seems to be the zero-equivalent value for the return type.
PopByte();
var retVal = ReadObject();
expr = new SymbolReference(null, null, null, "null"); // TODO: faulty obv, kind of illustrates the thing though.
}
else if(CurrentIs(StandardByteCodes.Nothing))
{
PopByte();
}
else
{
expr = DecompileExpression();
if (expr == null && PopByte() != (byte)StandardByteCodes.Nothing)
return null; //ERROR ?
}
var statement = new ReturnStatement(null, null, expr);
StatementLocations.Add(StartPositions.Pop(), statement);
return statement;
}
// TODO: guess for loop, probably requires a large restructure
public Statement DecompileForEach(bool isDynArray = false)
{
PopByte();
var scopeStatements = new List<Statement>();
var iteratorFunc = DecompileExpression();
if (iteratorFunc == null)
return null;
Expression dynArrVar = null;
Expression dynArrIndex = null;
bool unknByte = false;
if (isDynArray)
{
dynArrVar = DecompileExpression();
unknByte = Convert.ToBoolean(ReadByte());
dynArrIndex = DecompileExpression();
}
var scopeEnd = ReadUInt16(); // MemOff
ForEachScopes.Push(scopeEnd);
Scopes.Add(scopeStatements);
CurrentScope.Push(Scopes.Count - 1);
while (Position < Size)
{
if (CurrentIs(StandardByteCodes.IteratorNext) && PeekByte == (byte)StandardByteCodes.IteratorPop)
{
PopByte(); // IteratorNext
PopByte(); // IteratorPop
break;
}
var current = DecompileStatement();
if (current == null)
return null; // ERROR ?
scopeStatements.Add(current);
}
CurrentScope.Pop();
ForEachScopes.Pop();
if (isDynArray)
{
var builder = new CodeBuilderVisitor(); // what a wonderful hack, TODO.
iteratorFunc.AcceptVisitor(builder);
var arrayName = new SymbolReference(null, null, null, builder.GetCodeString());
var parameters = new List<Expression>() { dynArrVar, dynArrIndex };
iteratorFunc = new FunctionCall(arrayName, parameters, null, null);
}
var statement = new ForEachLoop(iteratorFunc, new CodeBody(scopeStatements, null, null), null, null);
StatementLocations.Add(StartPositions.Pop(), statement);
return statement;
}
public DelegateCall(SymbolReference del, List <Expression> arguments, SourcePosition start = null, SourcePosition end = null)
: base(ASTNodeType.FunctionCall, start, end)
{
DelegateReference = del;
Arguments = arguments;
}
public DefaultPropertiesBlock ConvertDefaultProperties(List<ME3DefaultProperty> properties)
{
var defaults = new List<Statement>();
foreach (var prop in properties)
{
var name = new SymbolReference(null, null, null, prop.Name);
var value = ConvertPropertyValue(prop);
defaults.Add(new AssignStatement(name, value, null, null));
}
return new DefaultPropertiesBlock(defaults, null, null);
}
// TODO: replace this ugly-ass hack with proper AST support.
public Expression DecompileNew()
{
PopByte();
var parameters = new List<Expression>();
for (int n = 0; n < 5; n++)
{
if (CurrentIs(StandardByteCodes.Nothing))
{
parameters.Add(null);
continue;
}
var param = DecompileExpression();
if (param == null)
return null; // ERROR
parameters.Add(param);
}
Expression first = null;
if ((parameters[0] ?? parameters[1] ?? parameters[2]) != null)
{
var innerParms = new List<Expression>();
if (parameters[0] != null)
innerParms.Add(parameters[0]);
if (parameters[1] != null)
innerParms.Add(parameters[1]);
if (parameters[2] != null)
innerParms.Add(parameters[2]);
first = new FunctionCall(new SymbolReference(null, null, null, "new"), innerParms, null, null);
}
else {
first = new SymbolReference(null, null, null, "new");
}
var second = parameters[3] ?? new SymbolReference(null, null, null, "NoClass??");
var op = new InOpDeclaration("", 0, true, null, null, null, null, null, null, null);
var firstHalf = new InOpReference(op, first, second, null, null);
StartPositions.Pop();
if (parameters[4] != null)
return new InOpReference(op, firstHalf, parameters[4], null, null);
else
return firstHalf;
}
public Expression DecompileStructMember()
{
PopByte();
var MemberRef = ReadObject();
var StructRef = ReadObject();
ReadByte(); // discard unknown bytes
ReadByte();
var expr = DecompileExpression(); // get the expression for struct instance
if (expr == null)
return null; // ERROR
StartPositions.Pop();
var member = new SymbolReference(null, null, null, MemberRef.ObjectName);
return new CompositeSymbolRef(expr, member, null, null);
}
public bool VisitNode(SymbolReference node)
{
throw new NotImplementedException();
}
public FunctionCall(SymbolReference func, List <Expression> parameters, SourcePosition start, SourcePosition end)
: base(ASTNodeType.FunctionCall, start, end)
{
Function = func;
Parameters = parameters;
}
private void DecompileDefaultParameterValues(List<Statement> statements)
{
OptionalParams = new Stack<FunctionParameter>();
var func = DataContainer as ME3Function;
if (func != null) // Gets all optional params for default value parsing
{
for (int n = 0; n < Parameters.Count; n++)
{
if (func.Parameters[n].PropertyFlags.HasFlag(PropertyFlags.OptionalParm))
OptionalParams.Push(Parameters[n]);
}
}
while (CurrentByte == (byte)StandardByteCodes.DefaultParmValue
|| CurrentByte == (byte)StandardByteCodes.Nothing)
{
StartPositions.Push((UInt16)Position);
var token = PopByte();
if (token == (byte)StandardByteCodes.DefaultParmValue) // default value assigned
{
ReadInt16(); //MemSize of value
var value = DecompileExpression();
PopByte(); // end of value
var builder = new CodeBuilderVisitor(); // what a wonderful hack, TODO.
value.AcceptVisitor(builder);
if (OptionalParams.Count != 0)
{
var parm = OptionalParams.Pop();
parm.Variables.First().Name += " = " + builder.GetCodeString();
StartPositions.Pop();
}
else
{ // TODO: weird, research how to deal with this
var comment = new SymbolReference(null, null, null, "// Orphaned Default Parm: " + builder.GetCodeString());
var statement = new ExpressionOnlyStatement(null, null, comment);
StatementLocations.Add(StartPositions.Pop(), statement);
statements.Add(statement);
}
}
}
}
