public void VisitNode(JSWhileLoop wl)
{
CheckLabel(wl);
BlockStack.Push(new EnclosingBlockEntry {
Block = wl,
ParentNode = ParentNode,
Depth = BlockStack.Count
});
try {
VisitChildren(wl);
} finally {
BlockStack.Pop();
}
}
public void VisitNode(JSWhileLoop wl)
{
var condInvocation = wl.Condition as JSInvocationExpression;
JSVariable enumeratorVariable;
if (
(condInvocation != null) &&
(condInvocation.JSMethod != null) &&
(condInvocation.JSMethod.Identifier == "MoveNext") &&
(condInvocation.JSMethod.Method.DeclaringType.Interfaces.Any((ii) => ii.Item1.FullName == "System.Collections.IEnumerator")) &&
((enumeratorVariable = condInvocation.ThisReference as JSVariable) != null)
) {
var enumeratorType = condInvocation.JSMethod.Method.DeclaringType;
while (EnableEnumeratorRemoval) {
var enumeratorAssignmentBeforeLoop = (
from boe in SeenAssignments
let boeLeftVar = (boe.Left as JSVariable)
where (boeLeftVar != null) && (boeLeftVar.Name == enumeratorVariable.Name)
select boe
).LastOrDefault();
if (enumeratorAssignmentBeforeLoop == null)
break;
var enumeratorValue = enumeratorAssignmentBeforeLoop.Right;
var assignmentInvocation = enumeratorValue as JSInvocationExpression;
if (assignmentInvocation == null) {
var rre = enumeratorValue as JSResultReferenceExpression;
if (rre != null)
assignmentInvocation = rre.Referent as JSInvocationExpression;
}
if (assignmentInvocation == null)
break;
var jsm = assignmentInvocation.JSMethod;
if (jsm == null)
break;
var attrParams2 = jsm.Method.Metadata.GetAttributeParameters("JSIL.Meta.JSUnderlyingArray");
if (attrParams2 != null) {
var arrayMember = (string)attrParams2[0].Value;
var lengthMember = (string)attrParams2[1].Value;
var replacement = ReplaceWhileLoopAndEnumerator(
wl, assignmentInvocation.ThisReference,
condInvocation.ThisReference, condInvocation.JSMethod.Method.DeclaringType,
arrayMember, lengthMember
);
ParentNode.ReplaceChild(wl, replacement);
EnumeratorsToKill.Add(enumeratorVariable);
VisitReplacement(replacement);
return;
}
break;
}
var attrParams = enumeratorType.Metadata.GetAttributeParameters("JSIL.Meta.JSIsArrayEnumerator");
if (attrParams != null) {
var arrayMember = (string)attrParams[0].Value;
var indexMember = (string)attrParams[1].Value;
var lengthMember = (string)attrParams[2].Value;
var replacement = ReplaceWhileLoop(
wl, condInvocation.ThisReference, condInvocation.JSMethod.Method.DeclaringType,
arrayMember, indexMember, lengthMember
);
ParentNode.ReplaceChild(wl, replacement);
VisitReplacement(replacement);
return;
}
}
VisitChildren(wl);
}
private JSForLoop ReplaceWhileLoopAndEnumerator(JSWhileLoop wl, JSExpression backingStore, JSExpression enumerator, TypeInfo enumeratorType, string arrayMember, string lengthMember)
{
var loopId = _NextLoopId++;
var arrayVariableName = String.Format("a${0:x}", loopId);
var indexVariableName = String.Format("i${0:x}", loopId);
var lengthVariableName = String.Format("l${0:x}", loopId);
var currentPropertyReference = enumeratorType.Definition.Properties.First((p) => p.Name == "Current");
var currentPropertyInfo = enumeratorType.Source.GetProperty(currentPropertyReference);
var itemType = currentPropertyInfo.ReturnType;
var arrayType = new ArrayType(itemType);
var arrayVariable = new JSVariable(
arrayVariableName, arrayType, Function.Method.Reference,
JSDotExpression.New(backingStore, new JSStringIdentifier(arrayMember, arrayType))
);
var indexVariable = new JSVariable(
indexVariableName, TypeSystem.Int32, Function.Method.Reference,
JSLiteral.New(0)
);
var lengthVariable = new JSVariable(
lengthVariableName, TypeSystem.Int32, Function.Method.Reference,
JSDotExpression.New(backingStore, new JSStringIdentifier(lengthMember, TypeSystem.Int32))
);
var initializer = new JSVariableDeclarationStatement(
new JSBinaryOperatorExpression(
JSOperator.Assignment, arrayVariable, arrayVariable.DefaultValue, arrayVariable.IdentifierType
),
new JSBinaryOperatorExpression(
JSOperator.Assignment, indexVariable, indexVariable.DefaultValue, indexVariable.IdentifierType
),
new JSBinaryOperatorExpression(
JSOperator.Assignment, lengthVariable, lengthVariable.DefaultValue, lengthVariable.IdentifierType
)
);
var condition = new JSBinaryOperatorExpression(
JSBinaryOperator.LessThan,
indexVariable, lengthVariable, TypeSystem.Boolean
);
var increment = new JSUnaryOperatorExpression(
JSUnaryOperator.PostIncrement,
indexVariable, TypeSystem.Int32
);
var result = new JSForLoop(
initializer, condition, new JSExpressionStatement(increment),
wl.Statements.ToArray()
);
result.Index = wl.Index;
new PropertyAccessReplacer(
enumerator, new JSProperty(currentPropertyReference, currentPropertyInfo),
new JSIndexerExpression(
arrayVariable, indexVariable,
itemType
)
).Visit(result);
return result;
}
public JSWhileLoop TranslateNode(ILWhileLoop loop)
{
JSExpression condition;
if (loop.Condition != null)
condition = TranslateNode(loop.Condition);
else
condition = JSLiteral.New(true);
var result = new JSWhileLoop(condition);
result.Label = String.Format("__loop{0}__", UnlabelledBlockCount++);
Blocks.Push(result);
var body = TranslateNode(loop.BodyBlock);
Blocks.Pop();
result.Statements.Add(body);
return result;
}
public void VisitNode(JSWhileLoop whileLoop)
{
JSVariable initVariable = null, lastVariable = null;
JSBinaryOperator initOperator = null;
JSExpression initValue = null;
var prevEStmt = PreviousSibling as JSExpressionStatement;
var prevVDS = PreviousSibling as JSVariableDeclarationStatement;
if (prevEStmt != null) {
var boe = prevEStmt.Expression as JSBinaryOperatorExpression;
if (
(boe != null) &&
(boe.Operator is JSAssignmentOperator) &&
(boe.Left is JSVariable)
) {
initVariable = (JSVariable)boe.Left;
initOperator = boe.Operator;
initValue = boe.Right;
}
} else if (prevVDS != null) {
var decl = prevVDS.Declarations.FirstOrDefault(
(d) => !d.IsNull
);
if (decl != null) {
initVariable = (JSVariable)decl.Left;
initOperator = decl.Operator;
initValue = decl.Right;
}
}
var lastStatement = whileLoop.Statements.LastOrDefault();
while ((lastStatement != null) && (lastStatement.GetType() == typeof(JSBlockStatement)))
lastStatement = ((JSBlockStatement)lastStatement).Statements.LastOrDefault();
var lastExpressionStatement = lastStatement as JSExpressionStatement;
if (lastExpressionStatement != null) {
var lastUoe = lastExpressionStatement.Expression as JSUnaryOperatorExpression;
var lastBoe = lastExpressionStatement.Expression as JSBinaryOperatorExpression;
if ((lastUoe != null) && (lastUoe.Operator is JSUnaryMutationOperator)) {
lastVariable = lastUoe.Expression as JSVariable;
} else if ((lastBoe != null) && (lastBoe.Operator is JSAssignmentOperator)) {
lastVariable = lastBoe.Left as JSVariable;
if (
(lastVariable != null) &&
!lastBoe.Right.AllChildrenRecursive.Any(
(n) => lastVariable.Equals(n)
)
) {
lastVariable = null;
}
}
}
var lastIfStatement = lastStatement as JSIfStatement;
if (
(lastIfStatement != null) &&
whileLoop.Condition is JSBooleanLiteral &&
((JSBooleanLiteral)whileLoop.Condition).Value
) {
var innerStatement = lastIfStatement.TrueClause;
while (innerStatement is JSBlockStatement) {
var bs = (JSBlockStatement)innerStatement;
if (bs.Statements.Count != 1) {
innerStatement = null;
break;
}
innerStatement = bs.Statements[0];
}
var eStmt = innerStatement as JSExpressionStatement;
if (eStmt != null) {
var breakExpr = eStmt.Expression as JSBreakExpression;
if ((breakExpr != null) && (breakExpr.TargetLabel == whileLoop.Label)) {
whileLoop.ReplaceChildRecursive(lastIfStatement, new JSNullStatement());
var doLoop = new JSDoLoop(
new JSUnaryOperatorExpression(JSOperator.LogicalNot, lastIfStatement.Condition),
whileLoop.Statements.ToArray()
);
doLoop.Label = whileLoop.Label;
ParentNode.ReplaceChild(whileLoop, doLoop);
VisitChildren(doLoop);
return;
}
}
}
bool cantBeFor = false;
if ((initVariable != null) && (lastVariable != null) &&
!initVariable.Equals(lastVariable)
) {
cantBeFor = true;
} else if ((initVariable ?? lastVariable) == null) {
cantBeFor = true;
} else if (!whileLoop.Condition.AllChildrenRecursive.Any(
(n) => (initVariable ?? lastVariable).Equals(n)
)) {
cantBeFor = true;
}
if (!cantBeFor) {
JSStatement initializer = null, increment = null;
if (initVariable != null) {
initializer = PreviousSibling as JSStatement;
ParentNode.ReplaceChild(PreviousSibling, new JSNullStatement());
}
if (lastVariable != null) {
increment = lastExpressionStatement;
whileLoop.ReplaceChildRecursive(lastExpressionStatement, new JSNullStatement());
}
var forLoop = new JSForLoop(
initializer, whileLoop.Condition, increment,
whileLoop.Statements.ToArray()
);
forLoop.Label = whileLoop.Label;
ParentNode.ReplaceChild(whileLoop, forLoop);
VisitChildren(forLoop);
} else {
VisitChildren(whileLoop);
}
}
public void VisitNode(JSWhileLoop wl)
{
var condInvocation = wl.Condition as JSInvocationExpression;
JSVariable enumeratorVariable;
if (
(condInvocation != null) &&
(condInvocation.JSMethod != null) &&
(condInvocation.JSMethod.Identifier == "MoveNext") &&
(condInvocation.JSMethod.Method.DeclaringType.Interfaces.Any((ii) => ii.Item1.FullName == "System.Collections.IEnumerator")) &&
((enumeratorVariable = condInvocation.ThisReference as JSVariable) != null)
) {
var enumeratorType = condInvocation.JSMethod.Method.DeclaringType;
while (EnableEnumeratorRemoval) {
var firstPass = FunctionSource.GetFirstPass(Function.Method.QualifiedIdentifier);
if (firstPass == null)
break;
var enumeratorAssignments = (from a in firstPass.Assignments where a.Target.Name == enumeratorVariable.Name select a).ToArray();
if (enumeratorAssignments.Length != 1)
break;
var enumeratorValue = enumeratorAssignments[0].NewValue;
var assignmentInvocation = enumeratorValue as JSInvocationExpression;
if (assignmentInvocation == null) {
var rre = enumeratorValue as JSResultReferenceExpression;
if (rre != null)
assignmentInvocation = rre.Referent as JSInvocationExpression;
}
if (assignmentInvocation == null)
break;
var jsm = assignmentInvocation.JSMethod;
if (jsm == null)
break;
var attrParams2 = jsm.Method.Metadata.GetAttributeParameters("JSIL.Meta.JSUnderlyingArray");
if (attrParams2 != null) {
var arrayMember = (string)attrParams2[0].Value;
var lengthMember = (string)attrParams2[1].Value;
var replacement = ReplaceWhileLoopAndEnumerator(
wl, assignmentInvocation.ThisReference,
condInvocation.ThisReference, condInvocation.JSMethod.Method.DeclaringType,
arrayMember, lengthMember
);
ParentNode.ReplaceChild(wl, replacement);
new VariableEliminator(enumeratorVariable, new JSNullExpression()).Visit(Function);
VisitReplacement(replacement);
}
break;
}
var attrParams = enumeratorType.Metadata.GetAttributeParameters("JSIL.Meta.JSIsArrayEnumerator");
if (attrParams != null) {
var arrayMember = (string)attrParams[0].Value;
var indexMember = (string)attrParams[1].Value;
var lengthMember = (string)attrParams[2].Value;
var replacement = ReplaceWhileLoop(
wl, condInvocation.ThisReference, condInvocation.JSMethod.Method.DeclaringType,
arrayMember, indexMember, lengthMember
);
ParentNode.ReplaceChild(wl, replacement);
VisitReplacement(replacement);
return;
}
}
VisitChildren(wl);
}