public override BoundNode VisitConditionalReceiver(BoundConditionalReceiver node)
{
var newtarget = _currentConditionalAccessTarget;
if (newtarget.Type.IsNullableType())
{
newtarget = MakeOptimizedGetValueOrDefault(node.Syntax, newtarget);
}
return(newtarget);
}
public override BoundNode VisitConditionalReceiver(BoundConditionalReceiver node)
{
if (node.Id == _receiverId)
{
#if DEBUG
_replaced++;
#endif
return(_receiver);
}
return(node);
}
/// <summary>
/// <![CDATA[
/// fixed(int* ptr = &v){ ... } == becomes ===>
///
/// pinned ref int pinnedTemp = ref v; // pinning managed ref
/// int* ptr = (int*)&pinnedTemp; // unsafe cast to unmanaged ptr
/// . . .
/// ]]>
/// </summary>
private BoundStatement InitializeFixedStatementGetPinnable(
BoundLocalDeclaration localDecl,
LocalSymbol localSymbol,
BoundFixedLocalCollectionInitializer fixedInitializer,
SyntheticBoundNodeFactory factory,
out LocalSymbol pinnedTemp)
{
TypeSymbol localType = localSymbol.Type;
BoundExpression initializerExpr = VisitExpression(fixedInitializer.Expression);
var initializerType = initializerExpr.Type;
var initializerSyntax = initializerExpr.Syntax;
var getPinnableMethod = fixedInitializer.GetPinnableOpt;
// intervening parens may have been skipped by the binder; find the declarator
VariableDeclaratorSyntax declarator = fixedInitializer.Syntax.FirstAncestorOrSelf <VariableDeclaratorSyntax>();
Debug.Assert(declarator != null);
// pinned ref int pinnedTemp
pinnedTemp = factory.SynthesizedLocal(
getPinnableMethod.ReturnType,
syntax: declarator,
isPinned: true,
//NOTE: different from the array and string cases
// RefReadOnly to allow referring to readonly variables. (technically we only "read" through the temp anyways)
refKind: RefKind.RefReadOnly,
kind: SynthesizedLocalKind.FixedReference);
BoundExpression callReceiver;
int currentConditionalAccessID = 0;
bool needNullCheck = !initializerType.IsValueType;
if (needNullCheck)
{
currentConditionalAccessID = ++_currentConditionalAccessID;
callReceiver = new BoundConditionalReceiver(
initializerSyntax,
currentConditionalAccessID,
initializerType);
}
else
{
callReceiver = initializerExpr;
}
// .GetPinnable()
var getPinnableCall = getPinnableMethod.IsStatic ?
factory.Call(null, getPinnableMethod, callReceiver) :
factory.Call(callReceiver, getPinnableMethod);
// temp =ref .GetPinnable()
var tempAssignment = factory.AssignmentExpression(
factory.Local(pinnedTemp),
getPinnableCall,
isRef: true);
// &pinnedTemp
var addr = new BoundAddressOfOperator(
factory.Syntax,
factory.Local(pinnedTemp),
type: fixedInitializer.ElementPointerType);
// (int*)&pinnedTemp
var pointerValue = factory.Convert(
localType,
addr,
fixedInitializer.ElementPointerTypeConversion);
// {pinnedTemp =ref .GetPinnable(), (int*)&pinnedTemp}
BoundExpression pinAndGetPtr = factory.Sequence(
locals: ImmutableArray <LocalSymbol> .Empty,
sideEffects: ImmutableArray.Create <BoundExpression>(tempAssignment),
result: pointerValue);
if (needNullCheck)
{
// initializer?.{temp =ref .GetPinnable(), (int*)&pinnedTemp} ?? default;
pinAndGetPtr = new BoundLoweredConditionalAccess(
initializerSyntax,
initializerExpr,
hasValueMethodOpt: null,
whenNotNull: pinAndGetPtr,
whenNullOpt: null, // just return default(T*)
currentConditionalAccessID,
localType);
}
// ptr = initializer?.{temp =ref .GetPinnable(), (int*)&pinnedTemp} ?? default;
BoundStatement localInit = InstrumentLocalDeclarationIfNecessary(localDecl, localSymbol, factory.Assignment(factory.Local(localSymbol), pinAndGetPtr));
return(localInit);
}