protected bool ValidateOperand(InstructionNode node, int operandIndex, ExpressionVariables variables)
{
if (operandIndex > node.OperandCount)
{
return(false);
}
return(ValidateOperand(node.GetOperand(operandIndex), variables));
}
public Node Transform(InstructionNode node, TypeSystem typeSystem, ExpressionVariables variables)
{
if (!Validate(node, variables))
{
return(null);
}
return(Transform(Result, node.Block, typeSystem, variables));
}
protected static Value Method(ExpressionNode node, ExpressionVariables variables)
{
string name = node.Token.Value;
//result = BuiltInMethods.Evaluate(name, node.Parameters);
//if (result != null)
// return result;
throw new CompilerException("ExpressionEvaluation: unknown method: " + name);
}
protected static Value IfStatement(ExpressionNode node, ExpressionVariables variables)
{
if (node.Parameters.Count < 2 || node.Parameters.Count > 3)
{
throw new CompilerException("ExpressionEvaluation: Incomplete if statement");
}
var condition = Evaluate(node.Parameters[0], variables);
return(Evaluate(node.Parameters[condition.IsTrue ? 1 : 2], variables));
}
public static Value Evaluate(ExpressionNode root, ExpressionVariables variables)
{
Debug.Assert(root != null);
if (root.Left != null && root.Right != null)
{
var left = Evaluate(root.Left, variables);
// shortcut evaluation
if (root.Token.TokenType == TokenType.And && left.IsFalse)
{
return(left);
}
else if (root.Token.TokenType == TokenType.Or && left.IsTrue)
{
return(left);
}
var right = Evaluate(root.Right, variables);
return(Eval(root.Token.TokenType, left, right));
}
else if (root.Left != null && root.Right == null)
{
var left = Evaluate(root.Left, variables);
return(Eval(root.Token.TokenType, left));
}
else if (root.Left == null && root.Right == null)
{
if (root.Token.TokenType == TokenType.If)
{
return(IfStatement(root, variables));
}
else if (root.Token.TokenType == TokenType.OperandVariable)
{
return(OperandVariable(root));
}
else if (root.Token.TokenType == TokenType.Method)
{
return(Method(root, variables));
}
else
{
// must be a literal
return(EvalLiteral(root.Token));
}
}
throw new CompilerException("ExpressionEvaluation: unexpected token type: " + root.Token);
}
protected Node Transform(Node node, BasicBlock block, TypeSystem typeSystem, ExpressionVariables variables)
{
var newNode = new InstructionNode(node.Instruction, block);
// todo: determine result type
// todo: determine size
int operandIndex = 0;
foreach (var nodeOperand in node.ParentNodes)
{
if (nodeOperand.NodeType == NodeType.Expression)
{
// todo: expressions
}
else if (nodeOperand.NodeType == NodeType.FixedIntegerConstant)
{
// todo
}
else if (nodeOperand.NodeType == NodeType.FixedDoubleConstant)
{
// todo
}
else if (nodeOperand.NodeType == NodeType.ConstantVariable)
{
newNode.SetOperand(operandIndex++, variables.GetOperand(nodeOperand.Alias));
continue;
}
else if (nodeOperand.NodeType == NodeType.PhyiscalRegister)
{
var type = typeSystem.BuiltIn.I4; // todo
Operand.CreateCPURegister(type, node.PhysicalRegister);
continue;
}
else if (nodeOperand.NodeType == NodeType.VirtualRegister)
{
newNode.SetOperand(operandIndex++, variables.GetOperand(nodeOperand.Alias));
continue;
}
else if (nodeOperand.NodeType == NodeType.OperandVariable)
{
newNode.SetOperand(operandIndex++, variables.GetOperand(nodeOperand.Alias));
continue;
}
throw new CompilerException("Error");
}
return(null);
}
public bool Match(InstructionNode node, ExpressionVariables variables)
{
if (NodeType == NodeType.Instruction)
{
if (!ValidateInstruction(node))
{
return(false);
}
for (int i = 0; i < ParentNodes.Count; i++)
{
var parentNode = ParentNodes[i];
if (NodeType == NodeType.Any)
{
continue;
}
if (parentNode.NodeType == NodeType.Instruction)
{
var operand = node.GetOperand(i);
if (operand.Definitions.Count != 1)
{
return(false);
}
var parent = operand.Definitions[0];
if (!parentNode.Match(parent, variables))
{
return(false);
}
}
else
{
if (!parentNode.ValidateOperand(node, i, variables))
{
return(false);
}
}
}
}
return(true);
}
public bool Validate(InstructionNode node, ExpressionVariables variables)
{
// validate the instructions and operands match
bool match = Match.Match(node, variables);
if (!match)
{
return(false);
}
// validate against any criteria
if (Condition == null)
{
return(true);
}
var result = ExpressionEvaluator.Evaluate(Condition, variables);
return(result.IsTrue);
}
public bool Validate(InstructionNode node)
{
var variables = new ExpressionVariables();
return(Validate(node, variables));
}
protected bool ValidateOperand(Operand operand, ExpressionVariables variables)
{
if (operand == null)
{
return(false);
}
if (NodeType == NodeType.Instruction)
{
return(false);
}
if (NodeType == NodeType.PhyiscalRegister && operand.IsCPURegister && operand.Register == PhysicalRegister)
{
return(true);
}
if (NodeType == NodeType.VirtualRegister && operand.IsVirtualRegister)
{
return(true);
}
if (NodeType == NodeType.FixedIntegerConstant && operand.IsResolvedConstant && operand.ConstantUnsignedLongInteger == ConstantInteger)
{
return(true);
}
if (NodeType == NodeType.ConstantVariable && operand.IsConstant)
{
var variableOperand = variables.GetOperand(Alias);
if (variableOperand == null)
{
variables.SetOperand(Alias, operand);
return(true);
}
else
{
return(variableOperand.ConstantUnsignedInteger == operand.ConstantUnsignedInteger);
}
}
if (NodeType == NodeType.OperandVariable)
{
var variableOperand = variables.GetOperand(Alias);
if (variableOperand == null)
{
variables.SetOperand(Alias, operand);
return(true);
}
else
{
return(variableOperand == operand);
}
}
if (NodeType == NodeType.TypeVariable)
{
var variableType = variables.GetType(Alias);
if (variableType == null)
{
variables.SetType(Alias, operand.Type);
return(true);
}
else
{
return(variableType == operand.Type);
}
}
return(false);
}