public override object VisitCFGForeachEnumereeEdge(ForeachEnumereeEdge x)
{
IsConditional = true;
var updated = x.Update(
(BoundBlock)Accept(x.Target),
(BoundExpression)Accept(x.Enumeree),
x.AreValuesAliased);
if (updated != x)
{
// Fix reference from the following ForEachMoveNextEdge
var moveNext = (ForeachMoveNextEdge)updated.NextBlock.NextEdge;
Debug.Assert(moveNext.EnumereeEdge == x);
updated.NextBlock.NextEdge = moveNext.Update(
moveNext.BodyBlock,
moveNext.NextBlock,
updated,
moveNext.KeyVariable,
moveNext.ValueVariable,
moveNext.MoveSpan);
}
return(updated);
}
public override void VisitForeachStmt(ForeachStmt x)
{
// binds enumeree expression & connect pre-enumeree-expr blocks
var boundEnumereeBag = _binder.BindWholeExpression(x.Enumeree, BoundAccess.Read);
ConnectBoundItemsBagBlocksToCurrentBlock(boundEnumereeBag);
var end = NewBlock();
var move = NewBlock();
var body = NewBlock();
// _current -> move -> body -> move -> ...
// ForeachEnumereeEdge : SimpleEdge
// x.Enumeree.GetEnumerator();
var enumereeEdge = new ForeachEnumereeEdge(_current, move, boundEnumereeBag.BoundElement, x.ValueVariable.Alias);
// ContinueTarget:
OpenBreakScope(end, move);
// bind reference expression for foreach key variable
BoundReferenceExpression keyVar = (x.KeyVariable != null) ?
(BoundReferenceExpression)_binder.BindWholeExpression(x.KeyVariable.Variable, BoundAccess.Write).GetOnlyBoundElement()
: null;
// bind reference expression for foreach value variable
var valueVar = (BoundReferenceExpression)(_binder.BindWholeExpression(
(Expression)x.ValueVariable.Variable ?? x.ValueVariable.List,
x.ValueVariable.Alias ? BoundAccess.Write.WithWriteRef(FlowAnalysis.TypeRefMask.AnyType) : BoundAccess.Write
).GetOnlyBoundElement());
// ForeachMoveNextEdge : ConditionalEdge
var moveEdge = new ForeachMoveNextEdge(move, body, end, enumereeEdge,
keyVar, valueVar,
Span.FromBounds(x.Enumeree.Span.End + 1, (x.KeyVariable ?? x.ValueVariable).Span.Start - 1).ToTextSpan() /*"as" between enumeree and variables*/);
// while (enumerator.MoveNext()) {
// var value = enumerator.Current.Value
// var key = enumerator.Current.Key
// Block
// { x.Body }
_current = WithOpenScope(WithNewOrdinal(body));
VisitElement(x.Body);
CloseScope();
// goto ContinueTarget;
Connect(_current, move);
// BreakTarget:
CloseBreakScope();
//
_current = WithNewOrdinal(end);
}
public ForeachMoveNextEdge Update(BoundBlock body, BoundBlock end, ForeachEnumereeEdge enumereeEdge, BoundReferenceExpression keyVar, BoundReferenceExpression /*!*/ valueVar, TextSpan moveSpan)
{
if (body == BodyBlock && end == _end && enumereeEdge == EnumereeEdge && keyVar == KeyVariable && valueVar == ValueVariable && moveSpan == MoveNextSpan)
{
return(this);
}
else
{
return(new ForeachMoveNextEdge(body, end, enumereeEdge, keyVar, valueVar, moveSpan));
}
}
internal ForeachMoveNextEdge(BoundBlock /*!*/ body, BoundBlock /*!*/ end, ForeachEnumereeEdge /*!*/ enumereeEdge, BoundReferenceExpression keyVar, BoundReferenceExpression /*!*/ valueVar, TextSpan moveSpan)
{
Contract.ThrowIfNull(body);
Contract.ThrowIfNull(end);
Contract.ThrowIfNull(enumereeEdge);
this.BodyBlock = body;
_end = end;
this.EnumereeEdge = enumereeEdge;
this.KeyVariable = keyVar;
this.ValueVariable = valueVar;
this.MoveNextSpan = moveSpan;
}
internal ForeachMoveNextEdge(BoundBlock /*!*/ source, BoundBlock /*!*/ body, BoundBlock /*!*/ end, ForeachEnumereeEdge /*!*/ enumereeEdge, BoundReferenceExpression keyVar, BoundReferenceExpression /*!*/ valueVar)
: base(source)
{
Contract.ThrowIfNull(body);
Contract.ThrowIfNull(end);
Contract.ThrowIfNull(enumereeEdge);
_body = body;
_end = end;
_enumereeEdge = enumereeEdge;
_keyVariable = keyVar;
_valueVariable = valueVar;
Connect(source);
}
public override void VisitForeachStmt(ForeachStmt x)
{
var end = NewBlock();
var move = NewBlock();
var body = NewBlock();
// _current -> move -> body -> move -> ...
// ForeachEnumereeEdge : SimpleEdge
// x.Enumeree.GetEnumerator();
var enumereeEdge = new ForeachEnumereeEdge(_current, move, _binder.BindExpression(x.Enumeree, BoundAccess.Read), x.ValueVariable.Alias);
// ContinueTarget:
OpenBreakScope(end, move);
// ForeachMoveNextEdge : ConditionalEdge
var moveEdge = new ForeachMoveNextEdge(move, body, end, enumereeEdge,
(x.KeyVariable != null) ? (BoundReferenceExpression)_binder.BindExpression(x.KeyVariable.Variable, BoundAccess.Write) : null,
(BoundReferenceExpression)_binder.BindExpression(
(Expression)x.ValueVariable.Variable ?? x.ValueVariable.List,
x.ValueVariable.Alias ? BoundAccess.Write.WithWriteRef(FlowAnalysis.TypeRefMask.AnyType) : BoundAccess.Write));
// while (enumerator.MoveNext()) {
// var key = enumerator.Current.Key
// var value = enumerator.Current.Value
// Block
// { x.Body }
_current = WithOpenScope(WithNewOrdinal(body));
VisitElement(x.Body);
CloseScope();
// goto ContinueTarget;
Connect(_current, move);
// BreakTarget:
CloseBreakScope();
//
_current = WithNewOrdinal(end);
}
public virtual void VisitCFGForeachEnumereeEdge(ForeachEnumereeEdge x)
{
Accept(x.Enumeree);
x.NextBlock.Accept(this);
}
internal ForeachMoveNextEdge(BoundBlock/*!*/source, BoundBlock/*!*/body, BoundBlock/*!*/end, ForeachEnumereeEdge/*!*/enumereeEdge, BoundReferenceExpression keyVar, BoundReferenceExpression/*!*/valueVar)
: base(source)
{
Contract.ThrowIfNull(body);
Contract.ThrowIfNull(end);
Contract.ThrowIfNull(enumereeEdge);
_body = body;
_end = end;
_enumereeEdge = enumereeEdge;
_keyVariable = keyVar;
_valueVariable = valueVar;
Connect(source);
}
public override void VisitCFGForeachEnumereeEdge(ForeachEnumereeEdge x)
{
Accept(x.Enumeree);
VisitCFGSimpleEdge(x);
}
public virtual void VisitCFGForeachEnumereeEdge(ForeachEnumereeEdge x)
{
Accept(x.Enumeree);
x.NextBlock.Accept(this);
}
public virtual TResult VisitCFGForeachEnumereeEdge(ForeachEnumereeEdge x) => DefaultVisitEdge(x);