public override object VisitCFGSwitchEdge(SwitchEdge x)
{
return(x.Update(
(BoundExpression)Accept(x.SwitchValue),
VisitBlockImmutableArray(x.CaseBlocks),
(BoundBlock)Accept(x.NextBlock)));
}
public virtual void VisitCFGSwitchEdge(SwitchEdge x)
{
Accept(x.SwitchValue);
//
var arr = x.CaseBlocks;
for (int i = 0; i < arr.Length; i++)
{
arr[i].Accept(this);
}
}
public override void VisitSwitchStmt(SwitchStmt x)
{
var items = x.SwitchItems;
if (items == null || items.Length == 0)
{
return;
}
var end = NewBlock();
bool hasDefault = false;
var cases = new List <CaseBlock>(items.Length);
for (int i = 0; i < items.Length; i++)
{
cases.Add(NewBlock(items[i]));
hasDefault |= (items[i] is DefaultItem);
}
if (!hasDefault)
{
// create implicit default:
cases.Add(NewBlock(new DefaultItem(x.Span, EmptyArray <Statement> .Instance)));
}
// SwitchEdge // Connects _current to cases
var edge = new SwitchEdge(_current, _binder.BindExpression(x.SwitchValue, BoundAccess.Read), cases.ToArray(), end);
_current = WithNewOrdinal(cases[0]);
OpenBreakScope(end, end); // NOTE: inside switch, Continue ~ Break
for (int i = 0; i < cases.Count; i++)
{
OpenScope(_current);
if (i < items.Length)
{
items[i].Statements.ForEach(VisitElement); // any break will connect block to end
}
CloseScope();
_current = WithNewOrdinal(Connect(_current, (i == cases.Count - 1) ? end : cases[i + 1]));
}
CloseBreakScope();
Debug.Assert(_current == end);
}
public override void VisitSwitchStmt(SwitchStmt x)
{
var items = x.SwitchItems;
if (items == null || items.Length == 0)
{
return;
}
// get bound item for switch value & connect potential pre-switch-value blocks
var boundBagForSwitchValue = _binder.BindWholeExpression(x.SwitchValue, BoundAccess.Read);
ConnectBoundItemsBagBlocksToCurrentBlock(boundBagForSwitchValue);
var switchValue = boundBagForSwitchValue.BoundElement;
var end = NewBlock();
bool hasDefault = false;
var cases = new List <CaseBlock>(items.Length);
for (int i = 0; i < items.Length; i++)
{
cases.Add(NewBlock(items[i]));
hasDefault |= (items[i] is DefaultItem);
}
if (!hasDefault)
{
// create implicit default:
cases.Add(NewBlock(new DefaultItem(x.Span, EmptyArray <Statement> .Instance)));
}
// if switch value isn't a constant & there're case values with preBoundStatements
// -> the switch value might get evaluated multiple times (see SwitchEdge.Generate) -> preemptively evaluate and cache it
if (!switchValue.IsConstant() && !cases.All(c => c.CaseValue.IsOnlyBoundElement))
{
var result = GeneratorSemanticsBinder.CreateAndAssignSynthesizedVariable(switchValue, BoundAccess.Read, $"<switchValueCacher>{x.Span}");
switchValue = result.BoundExpr;
_current.Add(new BoundExpressionStatement(result.Assignment));
}
// SwitchEdge // Connects _current to cases
var edge = new SwitchEdge(_current, switchValue, cases.ToArray(), end);
_current = WithNewOrdinal(cases[0]);
OpenBreakScope(end, end); // NOTE: inside switch, Continue ~ Break
for (int i = 0; i < cases.Count; i++)
{
OpenScope(_current);
if (i < items.Length)
{
items[i].Statements.ForEach(VisitElement); // any break will connect block to end
}
CloseScope();
_current = WithNewOrdinal(Connect(_current, (i == cases.Count - 1) ? end : cases[i + 1]));
}
CloseBreakScope();
Debug.Assert(_current == end);
}
public override void VisitCFGSwitchEdge(SwitchEdge x)
{
Accept(x.SwitchValue);
var state = _state;
foreach (var c in x.CaseBlocks)
{
TraverseToBlock(state, c);
}
}
public virtual void VisitCFGSwitchEdge(SwitchEdge x)
{
Accept(x.SwitchValue);
//
var arr = x.CaseBlocks;
for (int i = 0; i < arr.Length; i++)
arr[i].Accept(this);
}
public virtual TResult VisitCFGSwitchEdge(SwitchEdge x) => DefaultVisitEdge(x);