private void EvaluateVariableDeclaration(BoundVariableDeclaration node)
{
var value = EvaluateExpression(node.Initializer);
_variables[node.Variable] = value;
_lastValue = value;
}
private void EvaluateVariableDeclaration(BoundVariableDeclaration node)
{
var value = this.EvaluateExpression(node.Initializer) !;
this.LastValue = value;
this.Assign(node.Variable, value);
}
private void EvaluateVariableDeclaration(BoundVariableDeclaration statement)
{
var value = EvaluateExpression(statement.Initializer);
_variables[statement.Variable] = value;
_lastValue = value;
}
private void EvaluateVariableDeclaration(BoundVariableDeclaration node)
{
var value = EvaluateExpression(node.Initializer);
lastValue = value;
Assign(node.Variable, value);
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
//For Statements are now all While Statements
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
var variableExpression = new BoundVariableExpression(node.Variable);
var upperBoundSymbol = new VariableSymbol("upperBound", true, typeof(int));
var upperBoundDeclaration = new BoundVariableDeclaration(upperBoundSymbol, node.UpperBound);
var condition = new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.LessOrEqualsToken, typeof(int), typeof(int)),
new BoundVariableExpression(upperBoundSymbol)
);
var increment = new BoundExpressionStatement(
new BoundAssignmentExpression(
node.Variable,
new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.PlusToken, typeof(int), typeof(int)),
new BoundLiteralExpression(1)
)
)
);
var whileBody = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(node.Body, increment));
var whileStatement = new BoundWhileStatement(condition, whileBody);
var result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(
variableDeclaration,
upperBoundDeclaration,
whileStatement
));
return(RewriteStatement(result));
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
/*
* {
* let upperBound = <UpperBound>
* <variable> = <lowerBound>
* while <variable> < <UpperBound>
* {
* <statement>
* <variable> = <variable> + 1
* }
* }
*/
var upperBoundSymbol = new VariableSymbol("upperBound", true, node.UpperBound.Type, true);
var upperBoundDeclaration = new BoundVariableDeclaration(upperBoundSymbol, node.UpperBound);
var upperBoundExpression = new BoundVariableExpression(upperBoundSymbol);
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound); // LowerBound shouldn't be rewriten?
var variableExpression = new BoundVariableExpression(node.Variable);
var conditionOperator = BoundBinaryOperator.Bind(SyntaxKind.LessToken, TypeSymbol.Int, TypeSymbol.Int);
var condition = new BoundBinaryExpression(variableExpression, conditionOperator, upperBoundExpression); // UpperBound shouldn't be rewriten?
var incrementOperator = BoundBinaryOperator.Bind(SyntaxKind.PlusToken, node.Variable.Type, TypeSymbol.Int);
var increment = new BoundBinaryExpression(variableExpression, incrementOperator, new BoundLiteralExpression(1));
var incrementAssignment = new BoundAssignmentExpression(node.Variable, increment);
var incrementStatement = new BoundExpressionStatement(incrementAssignment);
var whileBlockStatement = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(node.Statement, incrementStatement));
var whileStatement = new BoundWhileStatement(condition, whileBlockStatement);
var result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(upperBoundDeclaration, variableDeclaration, whileStatement));
return(RewriteStatement(result));
}
private void EvaluateVariableDeclaration(BoundVariableDeclaration node)
{
var value = EvaluateExpression(node.Initializer);
Debug.Assert(value != null);
_lastValue = value;
Assign(node.Variable, value);
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
/*
* for <var> = <lower> to <upper>
* <body>
*
* ----->
* {
* var <var> = <lower>
* let upperBound = <upper>
* while (<var> <= <upperBound>)
* {
* <body>
* <var> = <var> + 1
* }
* }
*/
// var <var> = <lower>
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
// let upperBound = <upper>
var upperBoundSymbol = new VariableSymbol("upperBound", true, TypeSymbol.Int);
var upperBoundDeclaration = new BoundVariableDeclaration(upperBoundSymbol, node.UpperBound);
// <var>
var variableExpression = new BoundVariableExpression(node.Variable);
//<var> <= <upperBound>
var condition = new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.LessOrEqualsToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundVariableExpression(upperBoundSymbol)
);
// <var> = <var> + 1
var increment = new BoundExpressionStatement(
new BoundAssignmentExpression(
node.Variable,
new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.PlusToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundLiteralExpression(1)
)
)
);
var whileBlock = new BoundBlockStatement(ImmutableArray.Create(node.Body, increment));
var whileStatement = new BoundWhileStatement(condition, whileBlock);
var result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(
variableDeclaration,
upperBoundDeclaration,
whileStatement));
return(RewriteStatement(result));
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
// for <var> = <lower> to <upper>
// <body>
//
// ---->
// {
// var <var> = <lower>
// let upperBound = <upper>
// while (<var> <= upperBound)
// {
// <body>
// continue:
// <var> = <var> + 1
// }
// }
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
var variableExpression = new BoundVariableExpression(node.Variable);
var upperBoundSymbol = new LocalVariableSymbol("upperBound", true, TypeSymbol.Int);
var upperBoundDeclaration = new BoundVariableDeclaration(upperBoundSymbol, node.UpperBound);
var condition = new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.LessOrEqualsToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundVariableExpression(upperBoundSymbol)
);
var continueLabelStatement = new BoundLabelStatement(node.ContinueLabel);
var increment = new BoundExpressionStatement(
new BoundAssignmentExpression(
node.Variable,
new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.PlusToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundLiteralExpression(1)
)
)
);
var whileBody = new BoundBlockStatement(
ImmutableArray.Create <BoundStatement>(
node.Body,
continueLabelStatement,
increment
)
);
var whileStatement = new BoundWhileStatement(condition, whileBody, node.BreakLabel, GenerateLabel());
var result = new BoundBlockStatement(
ImmutableArray.Create <BoundStatement>(
variableDeclaration,
upperBoundDeclaration,
whileStatement
)
);
return(RewriteStatement(result));
}
private void EmitVariableDeclaration(ILProcessor ilProcessor, BoundVariableDeclaration node)
{
var typeReference = _knownTypes[node.Variable.Type];
var variableDefinition = new VariableDefinition(typeReference);
_locals.Add(node.Variable, variableDefinition);
ilProcessor.Body.Variables.Add(variableDefinition);
EmitExpression(ilProcessor, node.Initializer);
ilProcessor.Emit(OpCodes.Stloc, variableDefinition);
}
protected virtual void VisitVariableDeclaration(BoundVariableDeclaration node)
{
foreach (var qualifier in node.Qualifiers)
{
VisitVariableQualifier(qualifier);
}
if (node.InitializerOpt != null)
{
VisitInitializer(node.InitializerOpt);
}
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
BoundVariableDeclaration variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
BoundVariableExpression variableExpression = new BoundVariableExpression(node.Variable);
VariableSymbol upperVariableSymbol = new LocalVariableSymbol("upperBound", true, TypeSymbol.Int);
BoundVariableDeclaration upperVariableDeclaration = new BoundVariableDeclaration(upperVariableSymbol, node.UpperBound);
BoundBinaryExpression condition = new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.LessOrEqualsToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundVariableExpression(upperVariableSymbol)
);
BoundLabelStatement continueLabelStatement = new BoundLabelStatement(node.ContinueLabel);
BoundExpressionStatement increment = new BoundExpressionStatement(
new BoundAssignmentExpression(
node.Variable,
new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.PlusToken, TypeSymbol.Int, TypeSymbol.Int),
new BoundLiteralExpression(1)
)
)
);
BoundBlockStatement whileBody = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(
node.Body,
continueLabelStatement,
increment
));
BoundWhileStatement whileStatement = new BoundWhileStatement(condition, whileBody, node.BreakLabel, GenerateLabel());
BoundBlockStatement result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(
variableDeclaration,
upperVariableDeclaration,
whileStatement
));
return(RewriteStatement(result));
}
protected override BoundStatement RewriteForStatement(BoundForStatement node)
{
// for <var> = <lower> to <upper>
// <body>
// is rewritten to
// {
// var <Var> = <lower>
// while ()
//
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
var variableExpression = new BoundVariableExpression(node.Variable);
var condition = new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(SyntaxKind.LessOrEqualsToken, typeof(int), typeof(int)),
node.UpperBound);
var increment = new BoundExpressionStatement(
new BoundAssignmentExpression(
node.Variable,
new BoundBinaryExpression(
variableExpression,
BoundBinaryOperator.Bind(
SyntaxKind.PlusToken,
typeof(int),
typeof(int)),
new BoundLiteralExpression(1)
)
)
);
var whileBlock = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(node.Body, increment));
var whileStatement = new BoundWhileStatement(condition, whileBlock);
var result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(variableDeclaration, whileStatement));
return(RewriteStatement(result));
}
protected override BoundStatement RewriteVariableDeclaration(BoundVariableDeclaration node)
{
var rewrittenNode = base.RewriteVariableDeclaration(node);
return(new BoundSequencePointStatement(rewrittenNode.Syntax, rewrittenNode, rewrittenNode.Syntax.Location));
}
/// <inheritdoc/>
protected override BoundStatement RewriteForEllipsisStatement(BoundForEllipsisStatement node)
{
// for <var> := <lower> ... <upper>
// <body>
//
// ---->
//
// {
// var <var> = <lower>
// const upperBound = <upper>
// var step = 1
// if <var> greaterthan upperBound {
// step = -1
// }
// goto start
// body:
// <body>
// continue:
// <var> = <var> + step
// start:
// gotoTrue ((step > 0 && lower < upper) || (step < 0 && lower > upper)) body
// break:
// }
var variableDeclaration = new BoundVariableDeclaration(node.Variable, node.LowerBound);
var upperBoundSymbol = new LocalVariableSymbol("upperBound", isReadOnly: true, type: TypeSymbol.Int);
var upperBoundDeclaration = new BoundVariableDeclaration(upperBoundSymbol, node.UpperBound);
var stepBoundSymbol = new LocalVariableSymbol("step", isReadOnly: false, type: TypeSymbol.Int);
var stepBoundDeclaration = new BoundVariableDeclaration(
variable: stepBoundSymbol,
initializer: new BoundLiteralExpression(1));
var variableExpression = new BoundVariableExpression(node.Variable);
var upperBoundExpression = new BoundVariableExpression(upperBoundSymbol);
var stepBoundExpression = new BoundVariableExpression(stepBoundSymbol);
var ifLowerIsGreaterThanUpperExpression = new BoundBinaryExpression(
left: variableExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.GreaterToken, TypeSymbol.Int, TypeSymbol.Int),
right: upperBoundExpression);
var stepBoundAssingment = new BoundExpressionStatement(
expression: new BoundAssignmentExpression(
variable: stepBoundSymbol,
expression: new BoundLiteralExpression(-1)));
var ifLowerIsGreaterThanUpperIfStatement = new BoundIfStatement(
condition: ifLowerIsGreaterThanUpperExpression,
thenStatement: stepBoundAssingment,
elseStatement: null);
var startLabel = GenerateLabel();
var gotoStart = new BoundGotoStatement(startLabel);
var bodyLabel = GenerateLabel();
var bodyLabelStatement = new BoundLabelStatement(bodyLabel);
var continueLabelStatement = new BoundLabelStatement(node.ContinueLabel);
var increment = new BoundExpressionStatement(
expression: new BoundAssignmentExpression(
variable: node.Variable,
expression: new BoundBinaryExpression(
left: variableExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.PlusToken, TypeSymbol.Int, TypeSymbol.Int),
right: stepBoundExpression)));
var startLabelStatement = new BoundLabelStatement(startLabel);
var zeroLiteralExpression = new BoundLiteralExpression(0);
var stepGreaterThanZeroExpression = new BoundBinaryExpression(
left: stepBoundExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.GreaterToken, TypeSymbol.Int, TypeSymbol.Int),
right: zeroLiteralExpression);
var lowerLessThanUpperExpression = new BoundBinaryExpression(
left: variableExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.LessToken, TypeSymbol.Int, TypeSymbol.Int),
right: upperBoundExpression);
var positiveStepAndLowerLessThanUpper = new BoundBinaryExpression(
left: stepGreaterThanZeroExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.AmpersandAmpersandToken, TypeSymbol.Bool, TypeSymbol.Bool),
right: lowerLessThanUpperExpression);
var stepLessThanZeroExpression = new BoundBinaryExpression(
left: stepBoundExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.LessToken, TypeSymbol.Int, TypeSymbol.Int),
right: zeroLiteralExpression);
var lowerGreaterThanUpperExpression = new BoundBinaryExpression(
left: variableExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.GreaterToken, TypeSymbol.Int, TypeSymbol.Int),
right: upperBoundExpression);
var negativeStepAndLowerGreaterThanUpper = new BoundBinaryExpression(
left: stepLessThanZeroExpression,
op: BoundBinaryOperator.Bind(SyntaxKind.AmpersandAmpersandToken, TypeSymbol.Bool, TypeSymbol.Bool),
right: lowerGreaterThanUpperExpression);
var condition = new BoundBinaryExpression(
positiveStepAndLowerLessThanUpper,
BoundBinaryOperator.Bind(SyntaxKind.PipePipeToken, TypeSymbol.Bool, TypeSymbol.Bool),
negativeStepAndLowerGreaterThanUpper);
var gotoTrue = new BoundConditionalGotoStatement(bodyLabel, condition, jumpIfTrue: true);
var breakLabelStatement = new BoundLabelStatement(node.BreakLabel);
var result = new BoundBlockStatement(ImmutableArray.Create <BoundStatement>(
variableDeclaration,
upperBoundDeclaration,
stepBoundDeclaration,
ifLowerIsGreaterThanUpperIfStatement,
gotoStart,
bodyLabelStatement,
node.Body,
continueLabelStatement,
increment,
startLabelStatement,
gotoTrue,
breakLabelStatement));
return(RewriteStatement(result));
}
private void EvaluateVariableDeclaration(BoundVariableDeclaration statement)
{
_variables[statement.VariableSymbol] = EvaluateExpression(statement.Initializer);
}