public sealed override BoundNode VisitReturnStatement(BoundReturnStatement node)
{
if (node.ExpressionOpt != null)
{
Debug.Assert(_method.IsGenericTaskReturningAsync(F.Compilation));
return(F.Block(
F.Assignment(F.Local(_exprRetValue), (BoundExpression)Visit(node.ExpressionOpt)),
F.Goto(_exprReturnLabel)));
}
return(F.Goto(_exprReturnLabel));
}
public override BoundStatement InstrumentReturnStatement(BoundReturnStatement original, BoundStatement rewritten)
{
rewritten = base.InstrumentReturnStatement(original, rewritten);
if (original.WasCompilerGenerated && original.ExpressionOpt == null && original.Syntax.Kind() == SyntaxKind.Block)
{
// implicit return added by the compiler
return(new BoundSequencePointWithSpan(original.Syntax, rewritten, ((BlockSyntax)original.Syntax).CloseBraceToken.Span));
}
return(new BoundSequencePoint(original.Syntax, rewritten));
}
/// <summary>
/// Construct a body for an auto-property accessor (updating or returning the backing field).
/// </summary>
internal static BoundBlock ConstructAutoPropertyAccessorBody(SourceMemberMethodSymbol accessor)
{
Debug.Assert(accessor.MethodKind == MethodKind.PropertyGet || accessor.MethodKind == MethodKind.PropertySet);
var property = (SourcePropertySymbol)accessor.AssociatedSymbol;
CSharpSyntaxNode syntax = property.CSharpSyntaxNode;
BoundExpression thisReference = null;
if (!accessor.IsStatic)
{
var thisSymbol = accessor.ThisParameter;
thisReference = new BoundThisReference(syntax, thisSymbol.Type.TypeSymbol)
{
WasCompilerGenerated = true
};
}
var field = property.BackingField;
var fieldAccess = new BoundFieldAccess(syntax, thisReference, field, ConstantValue.NotAvailable)
{
WasCompilerGenerated = true
};
BoundStatement statement;
if (accessor.MethodKind == MethodKind.PropertyGet)
{
statement = new BoundReturnStatement(accessor.SyntaxNode, RefKind.None, fieldAccess);
}
else
{
Debug.Assert(accessor.MethodKind == MethodKind.PropertySet);
var parameter = accessor.Parameters[0];
statement = new BoundExpressionStatement(
accessor.SyntaxNode,
new BoundAssignmentOperator(
syntax,
fieldAccess,
new BoundParameter(syntax, parameter)
{
WasCompilerGenerated = true
},
property.Type.TypeSymbol)
{
WasCompilerGenerated = true
});
}
return(BoundBlock.SynthesizedNoLocals(syntax, statement));
}
public override BoundStatement InstrumentReturnStatement(BoundReturnStatement original, BoundStatement rewritten)
{
rewritten = base.InstrumentReturnStatement(original, rewritten);
// A synthesized return statement that does not return a value never requires instrumentation.
// A property set defined without a block has such a synthesized return statement.
// A synthesized return statement that does return a value does require instrumentation.
// A method, property get, or lambda defined without a block has such a synthesized return statement.
if (ReturnsValueWithinExpressionBodiedConstruct(original))
{
// The return statement for value-returning methods defined without a block is compiler generated, but requires instrumentation.
return(CollectDynamicAnalysis(original, rewritten));
}
return(AddDynamicAnalysis(original, rewritten));
}
// insert the implicit "return" statement at the end of the method body
// Normally, we wouldn't bother attaching syntax trees to compiler-generated nodes, but these
// ones are going to have sequence points.
internal static BoundBlock AppendImplicitReturn(BoundBlock body, MethodSymbol method)
{
Debug.Assert(body != null);
Debug.Assert(method != null);
SyntaxNode syntax = body.Syntax;
Debug.Assert(body.WasCompilerGenerated ||
syntax.IsKind(SyntaxKind.Block) ||
syntax.IsKind(SyntaxKind.ArrowExpressionClause) ||
syntax.IsKind(SyntaxKind.ConstructorDeclaration));
BoundStatement ret = (method.IsIterator && !method.IsAsync)
? (BoundStatement)BoundYieldBreakStatement.Synthesized(syntax)
: BoundReturnStatement.Synthesized(syntax, RefKind.None, null);
return(body.Update(body.Locals, body.LocalFunctions, body.IsUnsafeIL, body.Statements.Add(ret)));
}
private static bool ReturnsValueWithinExpressionBodiedConstruct(BoundReturnStatement returnStatement)
{
if (returnStatement.WasCompilerGenerated &&
returnStatement.ExpressionOpt != null &&
returnStatement.ExpressionOpt.Syntax != null)
{
SyntaxKind parentKind = returnStatement.ExpressionOpt.Syntax.Parent.Kind();
switch (parentKind)
{
case SyntaxKind.ParenthesizedLambdaExpression:
case SyntaxKind.SimpleLambdaExpression:
case SyntaxKind.ArrowExpressionClause:
return(true);
}
}
return(false);
}
public override BoundNode VisitReturnStatement(BoundReturnStatement node)
{
BoundStatement rewritten = (BoundStatement)base.VisitReturnStatement(node);
// NOTE: we will apply sequence points to synthesized return
// statements if they are contained in lambdas and have expressions
// or if they are expression-bodied properties.
// We do this to ensure that expression lambdas and expression-bodied
// properties have sequence points.
// We also add sequence points for the implicit "return" statement at the end of the method body
// (added by FlowAnalysisPass.AppendImplicitReturn). Implicitly added return for async method
// does not need sequence points added here since it would be done later (presumably during Async rewrite).
if (this.Instrument &&
(!node.WasCompilerGenerated ||
(node.ExpressionOpt != null ?
IsLambdaOrExpressionBodiedMember :
(node.Syntax.Kind() == SyntaxKind.Block && _factory.CurrentFunction?.IsAsync == false))))
{
rewritten = _instrumenter.InstrumentReturnStatement(node, rewritten);
}
return(rewritten);
}
/// <summary>
/// Generate a thread-safe accessor for a regular field-like event.
///
/// DelegateType tmp0 = _event; //backing field
/// DelegateType tmp1;
/// DelegateType tmp2;
/// do {
/// tmp1 = tmp0;
/// tmp2 = (DelegateType)Delegate.Combine(tmp1, value); //Remove for -=
/// tmp0 = Interlocked.CompareExchange<DelegateType>(ref _event, tmp2, tmp1);
/// } while ((object)tmp0 != (object)tmp1);
///
/// Note, if System.Threading.Interlocked.CompareExchange<T> is not available,
/// we emit the following code and mark the method Synchronized (unless it is a struct).
///
/// _event = (DelegateType)Delegate.Combine(_event, value); //Remove for -=
///
/// </summary>
internal static BoundBlock ConstructFieldLikeEventAccessorBody_Regular(SourceEventSymbol eventSymbol, bool isAddMethod, CSharpCompilation compilation, DiagnosticBag diagnostics)
{
CSharpSyntaxNode syntax = eventSymbol.CSharpSyntaxNode;
TypeSymbol delegateType = eventSymbol.Type.TypeSymbol;
MethodSymbol accessor = isAddMethod ? eventSymbol.AddMethod : eventSymbol.RemoveMethod;
ParameterSymbol thisParameter = accessor.ThisParameter;
TypeSymbol boolType = compilation.GetSpecialType(SpecialType.System_Boolean);
SpecialMember updateMethodId = isAddMethod ? SpecialMember.System_Delegate__Combine : SpecialMember.System_Delegate__Remove;
MethodSymbol updateMethod = (MethodSymbol)compilation.GetSpecialTypeMember(updateMethodId);
BoundStatement @return = new BoundReturnStatement(syntax,
refKind: RefKind.None,
expressionOpt: null)
{
WasCompilerGenerated = true
};
if (updateMethod == null)
{
MemberDescriptor memberDescriptor = SpecialMembers.GetDescriptor(updateMethodId);
diagnostics.Add(new CSDiagnostic(new CSDiagnosticInfo(ErrorCode.ERR_MissingPredefinedMember,
memberDescriptor.DeclaringTypeMetadataName,
memberDescriptor.Name),
syntax.Location));
return(BoundBlock.SynthesizedNoLocals(syntax, @return));
}
Binder.ReportUseSiteDiagnostics(updateMethod, diagnostics, syntax);
BoundThisReference fieldReceiver = eventSymbol.IsStatic ?
null :
new BoundThisReference(syntax, thisParameter.Type.TypeSymbol)
{
WasCompilerGenerated = true
};
BoundFieldAccess boundBackingField = new BoundFieldAccess(syntax,
receiver: fieldReceiver,
fieldSymbol: eventSymbol.AssociatedField,
constantValueOpt: null)
{
WasCompilerGenerated = true
};
BoundParameter boundParameter = new BoundParameter(syntax,
parameterSymbol: accessor.Parameters[0])
{
WasCompilerGenerated = true
};
BoundExpression delegateUpdate;
MethodSymbol compareExchangeMethod = (MethodSymbol)compilation.GetWellKnownTypeMember(WellKnownMember.System_Threading_Interlocked__CompareExchange_T);
if ((object)compareExchangeMethod == null)
{
// (DelegateType)Delegate.Combine(_event, value)
delegateUpdate = BoundConversion.SynthesizedNonUserDefined(syntax,
operand: BoundCall.Synthesized(syntax,
receiverOpt: null,
method: updateMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundBackingField, boundParameter)),
conversion: Conversion.ExplicitReference,
type: delegateType);
// _event = (DelegateType)Delegate.Combine(_event, value);
BoundStatement eventUpdate = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundBackingField,
right: delegateUpdate,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
return(BoundBlock.SynthesizedNoLocals(syntax,
statements: ImmutableArray.Create <BoundStatement>(
eventUpdate,
@return)));
}
compareExchangeMethod = compareExchangeMethod.Construct(ImmutableArray.Create <TypeSymbol>(delegateType));
Binder.ReportUseSiteDiagnostics(compareExchangeMethod, diagnostics, syntax);
GeneratedLabelSymbol loopLabel = new GeneratedLabelSymbol("loop");
const int numTemps = 3;
LocalSymbol[] tmps = new LocalSymbol[numTemps];
BoundLocal[] boundTmps = new BoundLocal[numTemps];
for (int i = 0; i < numTemps; i++)
{
tmps[i] = new SynthesizedLocal(accessor, TypeSymbolWithAnnotations.Create(delegateType), SynthesizedLocalKind.LoweringTemp);
boundTmps[i] = new BoundLocal(syntax, tmps[i], null, delegateType);
}
// tmp0 = _event;
BoundStatement tmp0Init = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[0],
right: boundBackingField,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// LOOP:
BoundStatement loopStart = new BoundLabelStatement(syntax,
label: loopLabel)
{
WasCompilerGenerated = true
};
// tmp1 = tmp0;
BoundStatement tmp1Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[1],
right: boundTmps[0],
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// (DelegateType)Delegate.Combine(tmp1, value)
delegateUpdate = BoundConversion.SynthesizedNonUserDefined(syntax,
operand: BoundCall.Synthesized(syntax,
receiverOpt: null,
method: updateMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundTmps[1], boundParameter)),
conversion: Conversion.ExplicitReference,
type: delegateType);
// tmp2 = (DelegateType)Delegate.Combine(tmp1, value);
BoundStatement tmp2Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[2],
right: delegateUpdate,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// Interlocked.CompareExchange<DelegateType>(ref _event, tmp2, tmp1)
BoundExpression compareExchange = BoundCall.Synthesized(syntax,
receiverOpt: null,
method: compareExchangeMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundBackingField, boundTmps[2], boundTmps[1]));
// tmp0 = Interlocked.CompareExchange<DelegateType>(ref _event, tmp2, tmp1);
BoundStatement tmp0Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[0],
right: compareExchange,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// tmp0 == tmp1 // i.e. exit when they are equal, jump to start otherwise
BoundExpression loopExitCondition = new BoundBinaryOperator(syntax,
operatorKind: BinaryOperatorKind.ObjectEqual,
left: boundTmps[0],
right: boundTmps[1],
constantValueOpt: null,
methodOpt: null,
resultKind: LookupResultKind.Viable,
type: boolType)
{
WasCompilerGenerated = true
};
// branchfalse (tmp0 == tmp1) LOOP
BoundStatement loopEnd = new BoundConditionalGoto(syntax,
condition: loopExitCondition,
jumpIfTrue: false,
label: loopLabel)
{
WasCompilerGenerated = true
};
return(new BoundBlock(syntax,
locals: tmps.AsImmutable(),
statements: ImmutableArray.Create <BoundStatement>(
tmp0Init,
loopStart,
tmp1Update,
tmp2Update,
tmp0Update,
loopEnd,
@return))
{
WasCompilerGenerated = true
});
}
/// <summary>
/// Generate a thread-safe accessor for a WinRT field-like event.
///
/// Add:
/// return EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable).AddEventHandler(value);
///
/// Remove:
/// EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable).RemoveEventHandler(value);
/// </summary>
internal static BoundBlock ConstructFieldLikeEventAccessorBody_WinRT(SourceEventSymbol eventSymbol, bool isAddMethod, CSharpCompilation compilation, DiagnosticBag diagnostics)
{
CSharpSyntaxNode syntax = eventSymbol.CSharpSyntaxNode;
MethodSymbol accessor = isAddMethod ? eventSymbol.AddMethod : eventSymbol.RemoveMethod;
Debug.Assert((object)accessor != null);
FieldSymbol field = eventSymbol.AssociatedField;
Debug.Assert((object)field != null);
NamedTypeSymbol fieldType = (NamedTypeSymbol)field.Type.TypeSymbol;
Debug.Assert(fieldType.Name == "EventRegistrationTokenTable");
MethodSymbol getOrCreateMethod = (MethodSymbol)Binder.GetWellKnownTypeMember(
compilation,
WellKnownMember.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T__GetOrCreateEventRegistrationTokenTable,
diagnostics,
syntax: syntax);
if ((object)getOrCreateMethod == null)
{
Debug.Assert(diagnostics.HasAnyErrors());
return(null);
}
getOrCreateMethod = getOrCreateMethod.AsMember(fieldType);
WellKnownMember processHandlerMember = isAddMethod
? WellKnownMember.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T__AddEventHandler
: WellKnownMember.System_Runtime_InteropServices_WindowsRuntime_EventRegistrationTokenTable_T__RemoveEventHandler;
MethodSymbol processHandlerMethod = (MethodSymbol)Binder.GetWellKnownTypeMember(
compilation,
processHandlerMember,
diagnostics,
syntax: syntax);
if ((object)processHandlerMethod == null)
{
Debug.Assert(diagnostics.HasAnyErrors());
return(null);
}
processHandlerMethod = processHandlerMethod.AsMember(fieldType);
// _tokenTable
BoundFieldAccess fieldAccess = new BoundFieldAccess(
syntax,
field.IsStatic ? null : new BoundThisReference(syntax, accessor.ThisParameter.Type.TypeSymbol),
field,
constantValueOpt: null)
{
WasCompilerGenerated = true
};
// EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable)
BoundCall getOrCreateCall = BoundCall.Synthesized(
syntax,
receiverOpt: null,
method: getOrCreateMethod,
arg0: fieldAccess);
// value
BoundParameter parameterAccess = new BoundParameter(
syntax,
accessor.Parameters[0]);
// EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable).AddHandler(value) // or RemoveHandler
BoundCall processHandlerCall = BoundCall.Synthesized(
syntax,
receiverOpt: getOrCreateCall,
method: processHandlerMethod,
arg0: parameterAccess);
if (isAddMethod)
{
// {
// return EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable).AddHandler(value);
// }
BoundStatement returnStatement = BoundReturnStatement.Synthesized(syntax, RefKind.None, processHandlerCall);
return(BoundBlock.SynthesizedNoLocals(syntax, returnStatement));
}
else
{
// {
// EventRegistrationTokenTable<Event>.GetOrCreateEventRegistrationTokenTable(ref _tokenTable).RemoveHandler(value);
// return;
// }
BoundStatement callStatement = new BoundExpressionStatement(syntax, processHandlerCall);
BoundStatement returnStatement = new BoundReturnStatement(syntax, RefKind.None, expressionOpt: null);
return(BoundBlock.SynthesizedNoLocals(syntax, callStatement, returnStatement));
}
}
private BoundStatement UnpendBranches(
AwaitFinallyFrame frame,
SynthesizedLocal pendingBranchVar,
SynthesizedLocal pendingException)
{
var parent = frame.ParentOpt;
// handle proxy labels if have any
var proxiedLabels = frame.proxiedLabels;
// skip 0 - it means we took no explicit branches
int i = 1;
var cases = ArrayBuilder <SyntheticBoundNodeFactory.SyntheticSwitchSection> .GetInstance();
if (proxiedLabels != null)
{
for (int cnt = proxiedLabels.Count; i <= cnt; i++)
{
var target = proxiedLabels[i - 1];
var parentProxy = parent.ProxyLabelIfNeeded(target);
var caseStatement = _F.SwitchSection(i, _F.Goto(parentProxy));
cases.Add(caseStatement);
}
}
if (frame.returnProxyLabel != null)
{
BoundLocal pendingValue = null;
if (frame.returnValue != null)
{
pendingValue = _F.Local(frame.returnValue);
}
SynthesizedLocal returnValue;
BoundStatement unpendReturn;
var returnLabel = parent.ProxyReturnIfNeeded(_F.CurrentFunction, pendingValue, out returnValue);
if (returnLabel == null)
{
unpendReturn = new BoundReturnStatement(_F.Syntax, RefKind.None, pendingValue);
}
else
{
if (pendingValue == null)
{
unpendReturn = _F.Goto(returnLabel);
}
else
{
unpendReturn = _F.Block(
_F.Assignment(
_F.Local(returnValue),
pendingValue),
_F.Goto(returnLabel));
}
}
var caseStatement = _F.SwitchSection(i, unpendReturn);
cases.Add(caseStatement);
}
return(_F.Switch(_F.Local(pendingBranchVar), cases.ToImmutableAndFree()));
}
public virtual BoundStatement InstrumentReturnStatement(BoundReturnStatement original, BoundStatement rewritten)
{
return(rewritten);
}
public override BoundStatement InstrumentReturnStatement(BoundReturnStatement original, BoundStatement rewritten)
{
return(Previous.InstrumentReturnStatement(original, rewritten));
}