/* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
private AST.Expression ParseSimpleExpr()
{
AST.Expression expr = null;
if (Stream.IsNumber())
{
expr = new AST.NumberExpression(Stream.GetNumber().NumberValue.Value);
Stream.MoveNext();
}
else if (Stream.IsString())
{
expr = new AST.StringExpression(Stream.GetString().Value);
Stream.MoveNext();
}
else if (Stream.IsKeyword("nil"))
{
expr = new AST.NilExpression();
Stream.MoveNext();
}
else if (Stream.IsKeyword("true"))
{
expr = new AST.BoolExpression(true);
Stream.MoveNext();
}
else if (Stream.IsKeyword("false"))
{
expr = new AST.BoolExpression(false);
Stream.MoveNext();
}
else if (Stream.IsKeyword("..."))
{
expr = new AST.VarArgsExpression();
Stream.MoveNext();
}
else if (Stream.IsKeyword("{"))
{
expr = ParseConstructor();
}
else if (Stream.IsKeyword("function"))
{
Stream.MoveNext();
return new AST.FunctionExpression(ParseBody());
}
else
{
expr = ParsePrimaryExpr();
}
return expr;
}
public void Visit(AST.ForStatement statement)
{
if (statement.Clause is AST.NumForClause)
{
AST.NumForClause clause = (AST.NumForClause)statement.Clause;
AST.Expression exp1 = clause.Expr1;
AST.Expression exp2 = clause.Expr2;
AST.Expression exp3 = clause.Expr3;
if (exp3 == null)
{
exp3 = new AST.NumberExpression(1);
}
CompilerState.SavedState save = State.SaveState();
// Initialize the variables for the loop.
int valPosition = State.stackPosition;
exp1.Visit(new ExpressionCompiler(State, 1));
int maxPosition = State.stackPosition;
exp2.Visit(new ExpressionCompiler(State, 1));
int stepPosition = State.stackPosition;
exp3.Visit(new ExpressionCompiler(State, 1));
// Verify that the variables are all numbers
foreach (int position in new int[] { valPosition, maxPosition, stepPosition })
{
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETGLOBAL(State.AddConstant("tonumber"))); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - position)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeCALL(1)); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakePOPVARGS(1, true));
}
String forCondLabel = State.getNewLabel();
State.bytecodes.Add(VirtualMachine.OpCodes.AND); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.AND); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.JMPTRUE); State.stackPosition--;
State.jumps.Add(new KeyValuePair<string, int>(forCondLabel, State.bytecodes.Count - 1));
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETGLOBAL(State.AddConstant("error"))); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeCALL(0));
State.bytecodes.Add(VirtualMachine.OpCodes.MakePOPVARGS(0, true)); State.stackPosition--;
// Condition for the loop
State.labels.Add(forCondLabel, State.bytecodes.Count);
State.bytecodes.Add(VirtualMachine.OpCodes.MakeLOADK(State.AddConstant(0.0))); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - stepPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.LESS); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - valPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - maxPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.LESSEQ); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.AND); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - stepPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeLOADK(State.AddConstant(0.0))); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.LESSEQ); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - maxPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - valPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.LESSEQ); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.AND); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.OR); State.stackPosition--;
String bodyLabel = State.getNewLabel();
String afterLabel = State.getNewLabel();
State.bytecodes.Add(VirtualMachine.OpCodes.JMPTRUE); State.stackPosition--;
State.jumps.Add(new KeyValuePair<string, int>(bodyLabel, State.bytecodes.Count - 1));
State.bytecodes.Add(VirtualMachine.OpCodes.JMP);
State.jumps.Add(new KeyValuePair<string, int>(afterLabel, State.bytecodes.Count - 1));
// Body
CompilerState.SavedState loopSave = State.SaveState();
String oldBreakLabel = State.currentBreakLabel;
CompilerState.SavedState oldBreakState = State.currentBreakState;
State.currentBreakLabel = afterLabel;
State.currentBreakState = State.SaveState();
State.labels.Add(bodyLabel, State.bytecodes.Count);
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - valPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeCLOSEVAR(1));
State.newClosedVars[clause.Name] = State.closureStackPosition; State.closureStackPosition++;
State.stackVars[clause.Name] = State.stackPosition - 1;
ChunkCompiler chunk = new ChunkCompiler(statement.Block, State, loopSave, false);
State.currentBreakLabel = oldBreakLabel;
State.currentBreakState = oldBreakState;
State.RestoreState(loopSave);
// Increment value
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - valPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - stepPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.ADD); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakePUTSTACK(State.stackPosition - valPosition)); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.JMP);
State.jumps.Add(new KeyValuePair<string, int>(forCondLabel, State.bytecodes.Count - 1));
State.labels.Add(afterLabel, State.bytecodes.Count);
State.RestoreState(save);
}
else
{
AST.ListForClause clause = (AST.ListForClause)statement.Clause;
CompilerState.SavedState forSave = State.SaveState();
int fPosition = State.stackPosition;
int sPosition = State.stackPosition + 1;
int vPosition = State.stackPosition + 2;
CompileExpressionList(clause.Expressions, 3);
String afterLabel = State.getNewLabel();
String startLabel = State.getNewLabel();
String bodyLabel = State.getNewLabel();
State.labels.Add(startLabel, State.bytecodes.Count);
CompilerState.SavedState loopSave = State.SaveState();
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - fPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - sPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - vPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeCALL(2)); State.stackPosition -= 2;
State.bytecodes.Add(VirtualMachine.OpCodes.MakePOPVARGS(clause.Names.Count, true)); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeCLOSEVAR(clause.Names.Count));
foreach (String name in clause.Names)
{
State.stackVars[name] = State.stackPosition;
State.stackPosition++;
State.newClosedVars[name] = State.closureStackPosition;
State.closureStackPosition++;
}
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(clause.Names.Count)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.MakePUTSTACK(State.stackPosition - vPosition)); State.stackPosition--;
State.bytecodes.Add(VirtualMachine.OpCodes.MakeGETSTACK(State.stackPosition - vPosition)); State.stackPosition++;
State.bytecodes.Add(VirtualMachine.OpCodes.JMPTRUE); State.stackPosition--;
State.jumps.Add(new KeyValuePair<string, int>(bodyLabel, State.bytecodes.Count - 1));
State.Cleanup(loopSave);
State.bytecodes.Add(VirtualMachine.OpCodes.JMP);
State.jumps.Add(new KeyValuePair<string, int>(afterLabel, State.bytecodes.Count - 1));
State.labels[bodyLabel] = State.bytecodes.Count;
String oldBreakLabel = State.currentBreakLabel;
CompilerState.SavedState oldBreakState = State.currentBreakState;
State.currentBreakLabel = afterLabel;
State.currentBreakState = State.SaveState();
ChunkCompiler chunk = new ChunkCompiler(statement.Block, State, loopSave, false);
State.currentBreakState = oldBreakState;
State.currentBreakLabel = oldBreakLabel;
State.RestoreState(loopSave);
State.bytecodes.Add(VirtualMachine.OpCodes.JMP);
State.jumps.Add(new KeyValuePair<string, int>(startLabel, State.bytecodes.Count - 1));
State.labels.Add(afterLabel, State.bytecodes.Count);
State.RestoreState(forSave);
}
}
