public DekiScriptExpression Visit(DekiScriptBinary expr, DekiScriptOptimizerState state)
{
DekiScriptExpression left = expr.Left.VisitWith(this, state);
DekiScriptExpression right = expr.Right.VisitWith(this, state);
DekiScriptExpression result = new DekiScriptBinary(expr.Line, expr.Column, expr.OpCode, left, right);
if ((left is DekiScriptLiteral) && (right is DekiScriptLiteral))
{
result = result.Evaluate(state.Env);
}
return(result);
}
private object Optimize(DekiScriptCaseBlock expr, DekiScriptExpression value, DekiScriptEvalMode mode, DekiScriptEnv env, out bool isDefaultCase)
{
List <DekiScriptExpression> conditions = new List <DekiScriptExpression>();
isDefaultCase = false;
for (int i = 0; i < expr.Conditions.Length; i++)
{
if (expr.Conditions[i] != null)
{
DekiScriptExpression condition = expr.Conditions[i].VisitWith(this, new DekiScriptOptimizerState(mode, env));
// check if condition always succeeds or always fails
if ((value is DekiScriptLiteral) && (condition is DekiScriptLiteral))
{
DekiScriptBinary test = new DekiScriptBinary(0, 0, DekiScriptBinary.Op.Equal, value, condition);
if (!test.Evaluate(env).IsNilFalseZero)
{
// NOTE (steveb): we wrap the outcome into a sequence to ensure proper handling of break/continue statements
// condition succeeded, return it
return(DekiScriptSequence.New(DekiScriptSequence.ScopeKind.ScopeCatchBreakAndContinue, expr.Body.VisitWith(this, new DekiScriptOptimizerState(mode, env))));
}
}
else
{
conditions.Add(condition);
}
}
else
{
isDefaultCase = true;
conditions.Add(null);
}
}
// check if any conditions were true or unknown
if (conditions.Count == 0)
{
return(null);
}
DekiScriptExpression body = expr.Body.VisitWith(this, new DekiScriptOptimizerState(mode, env));
return(new DekiScriptCaseBlock(conditions.ToArray(), body, expr.IsBlock));
}