private void CheckDynamic(BoundUnaryOperator node)
{
if (_inExpressionLambda && node.OperatorKind.IsDynamic())
{
Error(ErrorCode.ERR_ExpressionTreeContainsDynamicOperation, node);
}
}
/// <summary>
/// This rewriter lowers pre-/post- increment/decrement operations (initially represented as
/// unary operators). We use BoundSequenceExpressions because we need to capture the RHS of the
/// assignment in a temp variable.
/// </summary>
/// <remarks>
/// This rewriter assumes that it will be run before decimal rewriting (so that it does not have
/// to lower decimal constants and operations) and call rewriting (so that it does not have to
/// lower property accesses).
/// </remarks>
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
switch (node.OperatorKind.Operator())
{
case UnaryOperatorKind.PrefixDecrement:
case UnaryOperatorKind.PrefixIncrement:
case UnaryOperatorKind.PostfixDecrement:
case UnaryOperatorKind.PostfixIncrement:
Debug.Assert(false); // these should have been represented as a BoundIncrementOperator
return base.VisitUnaryOperator(node);
}
// TODO(tomat): We need to pass a parent operator kind into binary operator visitor.
// We circumvent logic in VisitExpression. The extra logic doesn't apply under these conditions so we are ok.
// This is a bit fragile however. Consider refactoring VisitExpression.
if (node.Operand.Kind == BoundKind.BinaryOperator)
{
// Optimization:
// Binary operator lowering combines the binary operator with IsTrue/IsFalse more efficiently than we can do here.
var binaryOperator = (BoundBinaryOperator)node.Operand;
if (node.OperatorKind == UnaryOperatorKind.DynamicTrue && binaryOperator.OperatorKind == BinaryOperatorKind.DynamicLogicalOr ||
node.OperatorKind == UnaryOperatorKind.DynamicFalse && binaryOperator.OperatorKind == BinaryOperatorKind.DynamicLogicalAnd)
{
return VisitBinaryOperator(binaryOperator, applyParentUnaryOperator: node);
}
}
BoundExpression loweredOperand = VisitExpression(node.Operand);
return MakeUnaryOperator(node, node.OperatorKind, node.Syntax, node.MethodOpt, loweredOperand, node.Type);
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
BoundSpillSequenceBuilder builder = null;
BoundExpression operand = VisitExpression(ref builder, node.Operand);
return(UpdateExpression(builder, node.Update(node.OperatorKind, operand, node.ConstantValueOpt, node.MethodOpt, node.ResultKind, node.Type)));
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
CheckUnsafeType(node);
CheckLiftedUnaryOp(node);
CheckDynamic(node);
return(base.VisitUnaryOperator(node));
}
/// <summary>
/// This rewriter lowers pre-/post- increment/decrement operations (initially represented as
/// unary operators). We use BoundSequenceExpressions because we need to capture the RHS of the
/// assignment in a temp variable.
/// </summary>
/// <remarks>
/// This rewriter assumes that it will be run before decimal rewriting (so that it does not have
/// to lower decimal constants and operations) and call rewriting (so that it does not have to
/// lower property accesses).
/// </remarks>
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
switch (node.OperatorKind.Operator())
{
case UnaryOperatorKind.PrefixDecrement:
case UnaryOperatorKind.PrefixIncrement:
case UnaryOperatorKind.PostfixDecrement:
case UnaryOperatorKind.PostfixIncrement:
Debug.Assert(false); // these should have been represented as a BoundIncrementOperator
return(base.VisitUnaryOperator(node));
}
// TODO(tomat): We need to pass a parent operator kind into binary operator visitor.
// We circumvent logic in VisitExpression. The extra logic doesn't apply under these conditions so we are ok.
// This is a bit fragile however. Consider refactoring VisitExpression.
if (node.Operand.Kind == BoundKind.BinaryOperator)
{
// Optimization:
// Binary operator lowering combines the binary operator with IsTrue/IsFalse more efficiently than we can do here.
var binaryOperator = (BoundBinaryOperator)node.Operand;
if (node.OperatorKind == UnaryOperatorKind.DynamicTrue && binaryOperator.OperatorKind == BinaryOperatorKind.DynamicLogicalOr ||
node.OperatorKind == UnaryOperatorKind.DynamicFalse && binaryOperator.OperatorKind == BinaryOperatorKind.DynamicLogicalAnd)
{
return(VisitBinaryOperator(binaryOperator, applyParentUnaryOperator: node));
}
}
BoundExpression loweredOperand = VisitExpression(node.Operand);
return(MakeUnaryOperator(node, node.OperatorKind, node.Syntax, node.MethodOpt, loweredOperand, node.Type));
}
public BoundExpression VisitBinaryOperator(BoundBinaryOperator node, BoundUnaryOperator applyParentUnaryOperator = null)
{
// In machine-generated code we frequently end up with binary operator trees that are deep on the left,
// such as a + b + c + d ...
// To avoid blowing the call stack, we make an explicit stack of the binary operators to the left,
// and then lower by traversing the explicit stack.
var stack = ArrayBuilder<BoundBinaryOperator>.GetInstance();
for (BoundBinaryOperator current = node; current != null; current = current.Left as BoundBinaryOperator)
{
stack.Push(current);
}
BoundExpression loweredLeft = VisitExpression(stack.Peek().Left);
while (stack.Count > 0)
{
BoundBinaryOperator original = stack.Pop();
BoundExpression loweredRight = VisitExpression(original.Right);
loweredLeft = MakeBinaryOperator(original, original.Syntax, original.OperatorKind, loweredLeft, loweredRight, original.Type, original.MethodOpt,
applyParentUnaryOperator: (stack.Count == 0) ? applyParentUnaryOperator : null);
}
stack.Free();
return loweredLeft;
}
private BoundExpression MakeBinaryOperator(
CSharpSyntaxNode syntax,
BinaryOperatorKind operatorKind,
BoundExpression loweredLeft,
BoundExpression loweredRight,
TypeSymbol type,
MethodSymbol method,
bool isPointerElementAccess = false,
bool isCompoundAssignment = false,
BoundUnaryOperator applyParentUnaryOperator = null)
{
return MakeBinaryOperator(null, syntax, operatorKind, loweredLeft, loweredRight, type, method, isPointerElementAccess, isCompoundAssignment, applyParentUnaryOperator);
}
private void CheckLiftedUnaryOp(BoundUnaryOperator node)
{
Debug.Assert(node != null);
if (!node.OperatorKind.IsLifted())
{
return;
}
// CS0458: The result of the expression is always 'null' of type '{0}'
if (node.Operand.NullableNeverHasValue())
{
Error(ErrorCode.WRN_AlwaysNull, node, node.Type);
}
}
private BoundExpression VisitUnaryOperator(BoundUnaryOperator node)
{
var arg = node.Operand;
var loweredArg = Visit(arg);
var opKind = node.OperatorKind;
var op = opKind & UnaryOperatorKind.OpMask;
var isChecked = (opKind & UnaryOperatorKind.Checked) != 0;
string opname;
switch (op)
{
case UnaryOperatorKind.UnaryPlus:
if ((object)node.MethodOpt == null)
{
return(loweredArg);
}
opname = "UnaryPlus";
break;
case UnaryOperatorKind.UnaryMinus:
opname = isChecked ? "NegateChecked" : "Negate";
break;
case UnaryOperatorKind.BitwiseComplement:
case UnaryOperatorKind.LogicalNegation:
opname = "Not";
break;
default:
throw ExceptionUtilities.UnexpectedValue(op);
}
if (node.OperatorKind.OperandTypes() == UnaryOperatorKind.Enum && (opKind & UnaryOperatorKind.Lifted) != 0)
{
Debug.Assert((object)node.MethodOpt == null);
var promotedType = PromotedType(arg.Type.StrippedType().GetEnumUnderlyingType());
promotedType = _nullableType.Construct(promotedType);
loweredArg = Convert(loweredArg, arg.Type, promotedType, isChecked, false);
var result = ExprFactory(opname, loweredArg);
return(Demote(result, node.Type, isChecked));
}
return(((object)node.MethodOpt == null)
? ExprFactory(opname, loweredArg)
: ExprFactory(opname, loweredArg, _bound.MethodInfo(node.MethodOpt)));
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
BoundExpression operand = (BoundExpression)this.Visit(node.Operand);
TypeSymbol type = this.VisitType(node.Type);
if (operand.Kind != BoundKind.SpillSequence)
{
return node.Update(node.OperatorKind, operand, node.ConstantValueOpt, node.MethodOpt, node.ResultKind, type);
}
var spill = (BoundSpillSequence)operand;
return RewriteSpillSequence(spill,
node.Update(
node.OperatorKind,
spill.Value,
node.ConstantValueOpt,
node.MethodOpt,
node.ResultKind,
type));
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
BoundExpression operand = (BoundExpression)this.Visit(node.Operand);
TypeSymbol type = this.VisitType(node.Type);
if (operand.Kind != BoundKind.SpillSequence)
{
return(node.Update(node.OperatorKind, operand, node.ConstantValueOpt, node.MethodOpt, node.ResultKind, type));
}
var spill = (BoundSpillSequence)operand;
return(RewriteSpillSequence(spill,
node.Update(
node.OperatorKind,
spill.Value,
node.ConstantValueOpt,
node.MethodOpt,
node.ResultKind,
type)));
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
BoundSpillSequence2 ss = null;
BoundExpression operand = VisitExpression(ref ss, node.Operand);
return UpdateExpression(ss, node.Update(node.OperatorKind, operand, node.ConstantValueOpt, node.MethodOpt, node.ResultKind, node.Type));
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
CSharpSyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return _factory.Literal(constant.BooleanValue);
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return MakeConversionNode(_factory.Literal(!constant.BooleanValue), type, @checked: false);
}
}
return _dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression();
}
else if (kind.IsLifted())
{
if (!_inExpressionLambda)
{
return LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type);
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!_inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
return BoundCall.Synthesized(syntax, null, method, loweredOperand);
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return loweredOperand;
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
_compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversionNode(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return MakeConversionNode(newNode.Syntax, newNode, Conversion.ExplicitEnumeration, type, @checked: false);
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)_compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!_inExpressionLambda)
{
return BoundCall.Synthesized(syntax, null, method, loweredOperand);
}
}
return (oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type);
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
CSharpSyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return(_factory.Literal(constant.BooleanValue));
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return(MakeConversionNode(_factory.Literal(!constant.BooleanValue), type, @checked: false));
}
}
return(_dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression());
}
else if (kind.IsLifted())
{
if (!_inExpressionLambda)
{
return(LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type));
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!_inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
// @t-mawind
// As usual, concept accesses need to be rewritten down to their
// default() form.
// Is this correct? It's mostly a copy over from the binary case,
// but the unary case is different enough to make me nervous.
if (method is SynthesizedWitnessMethodSymbol)
{
return(BoundCall.Synthesized(syntax, SynthesizeWitnessInvocationReceiver(syntax, ((SynthesizedWitnessMethodSymbol)method).Parent), method, loweredOperand));
}
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return(loweredOperand);
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
_compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversionNode(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return(MakeConversionNode(newNode.Syntax, newNode, Conversion.ExplicitEnumeration, type, @checked: false));
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)_compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!_inExpressionLambda)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
return((oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type));
}
private static void GetSymbolsAndResultKind(BoundUnaryOperator unaryOperator, out bool isDynamic, ref LookupResultKind resultKind, ref ImmutableArray<Symbol> symbols)
{
UnaryOperatorKind operandType = unaryOperator.OperatorKind.OperandTypes();
isDynamic = unaryOperator.OperatorKind.IsDynamic();
if (operandType == 0 || operandType == UnaryOperatorKind.UserDefined || unaryOperator.ResultKind != LookupResultKind.Viable)
{
if (!isDynamic)
{
GetSymbolsAndResultKind(unaryOperator, unaryOperator.MethodOpt, unaryOperator.OriginalUserDefinedOperatorsOpt, out symbols, out resultKind);
}
}
else
{
Debug.Assert((object)unaryOperator.MethodOpt == null && unaryOperator.OriginalUserDefinedOperatorsOpt.IsDefaultOrEmpty);
UnaryOperatorKind op = unaryOperator.OperatorKind.Operator();
symbols = ImmutableArray.Create<Symbol>(new SynthesizedIntrinsicOperatorSymbol(unaryOperator.Operand.Type.StrippedType(),
OperatorFacts.UnaryOperatorNameFromOperatorKind(op),
unaryOperator.Type.StrippedType(),
unaryOperator.OperatorKind.IsChecked()));
resultKind = unaryOperator.ResultKind;
}
}
private static bool IsUserDefinedTrueOrFalse(BoundUnaryOperator @operator)
{
UnaryOperatorKind operatorKind = @operator.OperatorKind;
return operatorKind == UnaryOperatorKind.UserDefinedTrue || operatorKind == UnaryOperatorKind.UserDefinedFalse;
}
private BoundExpression MakeBinaryOperator(
BoundBinaryOperator oldNode,
CSharpSyntaxNode syntax,
BinaryOperatorKind operatorKind,
BoundExpression loweredLeft,
BoundExpression loweredRight,
TypeSymbol type,
MethodSymbol method,
bool isPointerElementAccess = false,
bool isCompoundAssignment = false,
BoundUnaryOperator applyParentUnaryOperator = null)
{
Debug.Assert(oldNode == null || (oldNode.Syntax == syntax));
if (_inExpressionLambda)
{
switch (operatorKind.Operator() | operatorKind.OperandTypes())
{
case BinaryOperatorKind.ObjectAndStringConcatenation:
case BinaryOperatorKind.StringAndObjectConcatenation:
case BinaryOperatorKind.StringConcatenation:
return RewriteStringConcatenation(syntax, operatorKind, loweredLeft, loweredRight, type);
case BinaryOperatorKind.DelegateCombination:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__Combine);
case BinaryOperatorKind.DelegateRemoval:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__Remove);
case BinaryOperatorKind.DelegateEqual:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__op_Equality);
case BinaryOperatorKind.DelegateNotEqual:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__op_Inequality);
}
}
else
// try to lower the expression.
{
if (operatorKind.IsDynamic())
{
Debug.Assert(!isPointerElementAccess);
if (operatorKind.IsLogical())
{
return MakeDynamicLogicalBinaryOperator(syntax, operatorKind, loweredLeft, loweredRight, method, type, isCompoundAssignment, applyParentUnaryOperator);
}
else
{
Debug.Assert((object)method == null);
return _dynamicFactory.MakeDynamicBinaryOperator(operatorKind, loweredLeft, loweredRight, isCompoundAssignment, type).ToExpression();
}
}
if (operatorKind.IsLifted())
{
return RewriteLiftedBinaryOperator(syntax, operatorKind, loweredLeft, loweredRight, type, method);
}
if (operatorKind.IsUserDefined())
{
return LowerUserDefinedBinaryOperator(syntax, operatorKind, loweredLeft, loweredRight, type, method);
}
switch (operatorKind.OperatorWithLogical() | operatorKind.OperandTypes())
{
case BinaryOperatorKind.NullableNullEqual:
case BinaryOperatorKind.NullableNullNotEqual:
return RewriteNullableNullEquality(syntax, operatorKind, loweredLeft, loweredRight, type);
case BinaryOperatorKind.ObjectAndStringConcatenation:
case BinaryOperatorKind.StringAndObjectConcatenation:
case BinaryOperatorKind.StringConcatenation:
return RewriteStringConcatenation(syntax, operatorKind, loweredLeft, loweredRight, type);
case BinaryOperatorKind.StringEqual:
return RewriteStringEquality(oldNode, syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_String__op_Equality);
case BinaryOperatorKind.StringNotEqual:
return RewriteStringEquality(oldNode, syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_String__op_Inequality);
case BinaryOperatorKind.DelegateCombination:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__Combine);
case BinaryOperatorKind.DelegateRemoval:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__Remove);
case BinaryOperatorKind.DelegateEqual:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__op_Equality);
case BinaryOperatorKind.DelegateNotEqual:
return RewriteDelegateOperation(syntax, operatorKind, loweredLeft, loweredRight, type, SpecialMember.System_Delegate__op_Inequality);
case BinaryOperatorKind.LogicalBoolAnd:
if (loweredRight.ConstantValue == ConstantValue.True) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.True) return loweredRight;
if (loweredLeft.ConstantValue == ConstantValue.False) return loweredLeft;
if (loweredRight.Kind == BoundKind.Local || loweredRight.Kind == BoundKind.Parameter)
{
operatorKind &= ~BinaryOperatorKind.Logical;
}
goto default;
case BinaryOperatorKind.LogicalBoolOr:
if (loweredRight.ConstantValue == ConstantValue.False) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.False) return loweredRight;
if (loweredLeft.ConstantValue == ConstantValue.True) return loweredLeft;
if (loweredRight.Kind == BoundKind.Local || loweredRight.Kind == BoundKind.Parameter)
{
operatorKind &= ~BinaryOperatorKind.Logical;
}
goto default;
case BinaryOperatorKind.BoolAnd:
if (loweredRight.ConstantValue == ConstantValue.True) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.True) return loweredRight;
goto default;
case BinaryOperatorKind.BoolOr:
if (loweredRight.ConstantValue == ConstantValue.False) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.False) return loweredRight;
goto default;
case BinaryOperatorKind.BoolEqual:
if (loweredLeft.ConstantValue == ConstantValue.True) return loweredRight;
if (loweredRight.ConstantValue == ConstantValue.True) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.False)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredRight, loweredRight.Type);
if (loweredRight.ConstantValue == ConstantValue.False)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredLeft, loweredLeft.Type);
goto default;
case BinaryOperatorKind.BoolNotEqual:
if (loweredLeft.ConstantValue == ConstantValue.False) return loweredRight;
if (loweredRight.ConstantValue == ConstantValue.False) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.True)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredRight, loweredRight.Type);
if (loweredRight.ConstantValue == ConstantValue.True)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredLeft, loweredLeft.Type);
goto default;
case BinaryOperatorKind.BoolXor:
if (loweredLeft.ConstantValue == ConstantValue.False) return loweredRight;
if (loweredRight.ConstantValue == ConstantValue.False) return loweredLeft;
if (loweredLeft.ConstantValue == ConstantValue.True)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredRight, loweredRight.Type);
if (loweredRight.ConstantValue == ConstantValue.True)
return MakeUnaryOperator(UnaryOperatorKind.BoolLogicalNegation, syntax, null, loweredLeft, loweredLeft.Type);
goto default;
case BinaryOperatorKind.IntLeftShift:
case BinaryOperatorKind.UIntLeftShift:
case BinaryOperatorKind.IntRightShift:
case BinaryOperatorKind.UIntRightShift:
return RewriteBuiltInShiftOperation(oldNode, syntax, operatorKind, loweredLeft, loweredRight, type, 0x1F);
case BinaryOperatorKind.LongLeftShift:
case BinaryOperatorKind.ULongLeftShift:
case BinaryOperatorKind.LongRightShift:
case BinaryOperatorKind.ULongRightShift:
return RewriteBuiltInShiftOperation(oldNode, syntax, operatorKind, loweredLeft, loweredRight, type, 0x3F);
case BinaryOperatorKind.DecimalAddition:
case BinaryOperatorKind.DecimalSubtraction:
case BinaryOperatorKind.DecimalMultiplication:
case BinaryOperatorKind.DecimalDivision:
case BinaryOperatorKind.DecimalRemainder:
case BinaryOperatorKind.DecimalEqual:
case BinaryOperatorKind.DecimalNotEqual:
case BinaryOperatorKind.DecimalLessThan:
case BinaryOperatorKind.DecimalLessThanOrEqual:
case BinaryOperatorKind.DecimalGreaterThan:
case BinaryOperatorKind.DecimalGreaterThanOrEqual:
return RewriteDecimalBinaryOperation(syntax, loweredLeft, loweredRight, operatorKind);
case BinaryOperatorKind.PointerAndIntAddition:
case BinaryOperatorKind.PointerAndUIntAddition:
case BinaryOperatorKind.PointerAndLongAddition:
case BinaryOperatorKind.PointerAndULongAddition:
case BinaryOperatorKind.PointerAndIntSubtraction:
case BinaryOperatorKind.PointerAndUIntSubtraction:
case BinaryOperatorKind.PointerAndLongSubtraction:
case BinaryOperatorKind.PointerAndULongSubtraction:
if (loweredRight.IsDefaultValue())
{
return loweredLeft;
}
return RewritePointerNumericOperator(syntax, operatorKind, loweredLeft, loweredRight, type, isPointerElementAccess, isLeftPointer: true);
case BinaryOperatorKind.IntAndPointerAddition:
case BinaryOperatorKind.UIntAndPointerAddition:
case BinaryOperatorKind.LongAndPointerAddition:
case BinaryOperatorKind.ULongAndPointerAddition:
if (loweredLeft.IsDefaultValue())
{
return loweredRight;
}
return RewritePointerNumericOperator(syntax, operatorKind, loweredLeft, loweredRight, type, isPointerElementAccess, isLeftPointer: false);
case BinaryOperatorKind.PointerSubtraction:
return RewritePointerSubtraction(operatorKind, loweredLeft, loweredRight, type);
case BinaryOperatorKind.IntAddition:
case BinaryOperatorKind.UIntAddition:
case BinaryOperatorKind.LongAddition:
case BinaryOperatorKind.ULongAddition:
if (loweredLeft.IsDefaultValue())
{
return loweredRight;
}
if (loweredRight.IsDefaultValue())
{
return loweredLeft;
}
goto default;
case BinaryOperatorKind.IntSubtraction:
case BinaryOperatorKind.LongSubtraction:
case BinaryOperatorKind.UIntSubtraction:
case BinaryOperatorKind.ULongSubtraction:
if (loweredRight.IsDefaultValue())
{
return loweredLeft;
}
goto default;
case BinaryOperatorKind.IntMultiplication:
case BinaryOperatorKind.LongMultiplication:
case BinaryOperatorKind.UIntMultiplication:
case BinaryOperatorKind.ULongMultiplication:
if (loweredLeft.IsDefaultValue())
{
return loweredLeft;
}
if (loweredRight.IsDefaultValue())
{
return loweredRight;
}
if (loweredLeft.ConstantValue?.UInt64Value == 1)
{
return loweredRight;
}
if (loweredRight.ConstantValue?.UInt64Value == 1)
{
return loweredLeft;
}
goto default;
case BinaryOperatorKind.IntGreaterThan:
case BinaryOperatorKind.IntLessThanOrEqual:
if (loweredLeft.Kind == BoundKind.ArrayLength && loweredRight.IsDefaultValue())
{
//array length is never negative
var newOp = operatorKind == BinaryOperatorKind.IntGreaterThan ?
BinaryOperatorKind.NotEqual :
BinaryOperatorKind.Equal;
operatorKind &= ~BinaryOperatorKind.OpMask;
operatorKind |= newOp;
loweredLeft = UnconvertArrayLength((BoundArrayLength)loweredLeft);
}
goto default;
case BinaryOperatorKind.IntLessThan:
case BinaryOperatorKind.IntGreaterThanOrEqual:
if (loweredRight.Kind == BoundKind.ArrayLength && loweredLeft.IsDefaultValue())
{
//array length is never negative
var newOp = operatorKind == BinaryOperatorKind.IntLessThan ?
BinaryOperatorKind.NotEqual :
BinaryOperatorKind.Equal;
operatorKind &= ~BinaryOperatorKind.OpMask;
operatorKind |= newOp;
loweredRight = UnconvertArrayLength((BoundArrayLength)loweredRight);
}
goto default;
case BinaryOperatorKind.IntEqual:
case BinaryOperatorKind.IntNotEqual:
if (loweredLeft.Kind == BoundKind.ArrayLength && loweredRight.IsDefaultValue())
{
loweredLeft = UnconvertArrayLength((BoundArrayLength)loweredLeft);
}
else if (loweredRight.Kind == BoundKind.ArrayLength && loweredLeft.IsDefaultValue())
{
loweredRight = UnconvertArrayLength((BoundArrayLength)loweredRight);
}
goto default;
default:
break;
}
}
return (oldNode != null) ?
oldNode.Update(operatorKind, loweredLeft, loweredRight, oldNode.ConstantValueOpt, oldNode.MethodOpt, oldNode.ResultKind, type) :
new BoundBinaryOperator(syntax, operatorKind, loweredLeft, loweredRight, null, null, LookupResultKind.Viable, type);
}
private BoundExpression VisitUnaryOperator(BoundUnaryOperator node)
{
var arg = node.Operand;
var loweredArg = Visit(arg);
var opKind = node.OperatorKind;
var op = opKind & UnaryOperatorKind.OpMask;
var isChecked = (opKind & UnaryOperatorKind.Checked) != 0;
string opname;
switch (op)
{
case UnaryOperatorKind.UnaryPlus:
if ((object)node.MethodOpt == null)
{
return loweredArg;
}
opname = "UnaryPlus";
break;
case UnaryOperatorKind.UnaryMinus:
opname = isChecked ? "NegateChecked" : "Negate";
break;
case UnaryOperatorKind.BitwiseComplement:
case UnaryOperatorKind.LogicalNegation:
opname = "Not";
break;
default:
throw ExceptionUtilities.UnexpectedValue(op);
}
if (node.OperatorKind.OperandTypes() == UnaryOperatorKind.Enum && (opKind & UnaryOperatorKind.Lifted) != 0)
{
Debug.Assert((object)node.MethodOpt == null);
var promotedType = PromotedType(arg.Type.StrippedType().GetEnumUnderlyingType());
promotedType = _nullableType.Construct(promotedType);
loweredArg = Convert(loweredArg, arg.Type, promotedType, isChecked, false);
var result = ExprFactory(opname, loweredArg);
return Demote(result, node.Type, isChecked);
}
return ((object)node.MethodOpt == null)
? ExprFactory(opname, loweredArg)
: ExprFactory(opname, loweredArg, _bound.MethodInfo(node.MethodOpt));
}
private void CheckLiftedUnaryOp(BoundUnaryOperator node)
{
Debug.Assert(node != null);
if (!node.OperatorKind.IsLifted())
{
return;
}
// CS0458: The result of the expression is always 'null' of type '{0}'
if (node.Operand.NullableNeverHasValue())
{
Error(ErrorCode.WRN_AlwaysNull, node, node.Type);
}
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
SyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return(_factory.Literal(constant.BooleanValue));
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return(MakeConversionNode(_factory.Literal(!constant.BooleanValue), type, @checked: false));
}
}
return(_dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression());
}
else if (kind.IsLifted())
{
if (!_inExpressionLambda)
{
return(LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type));
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!_inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return(loweredOperand);
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
_compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversionNode(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return(MakeConversionNode(newNode.Syntax, newNode, Conversion.ExplicitEnumeration, type, @checked: false));
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)_compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!_inExpressionLambda)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
return((oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type));
}
private void CheckDynamic(BoundUnaryOperator node)
{
if (_inExpressionLambda && node.OperatorKind.IsDynamic())
{
Error(ErrorCode.ERR_ExpressionTreeContainsDynamicOperation, node);
}
}
private BoundExpression MakeDynamicLogicalBinaryOperator(
CSharpSyntaxNode syntax,
BinaryOperatorKind operatorKind,
BoundExpression loweredLeft,
BoundExpression loweredRight,
MethodSymbol leftTruthOperator,
TypeSymbol type,
bool isCompoundAssignment,
BoundUnaryOperator applyParentUnaryOperator)
{
Debug.Assert(operatorKind.Operator() == BinaryOperatorKind.And || operatorKind.Operator() == BinaryOperatorKind.Or);
// Dynamic logical && and || operators are lowered as follows:
// left && right -> IsFalse(left) ? left : And(left, right)
// left || right -> IsTrue(left) ? left : Or(left, right)
//
// Optimization: If the binary AND/OR is directly contained in IsFalse/IsTrue operator (parentUnaryOperator != null)
// we can avoid calling IsFalse/IsTrue twice on the same object.
// IsFalse(left && right) -> IsFalse(left) || IsFalse(And(left, right))
// IsTrue(left || right) -> IsTrue(left) || IsTrue(Or(left, right))
bool isAnd = operatorKind.Operator() == BinaryOperatorKind.And;
// Operator to be used to test the left operand:
var testOperator = isAnd ? UnaryOperatorKind.DynamicFalse : UnaryOperatorKind.DynamicTrue;
// VisitUnaryOperator ensures we are never called with parentUnaryOperator != null when we can't perform the optimization.
Debug.Assert(applyParentUnaryOperator == null || applyParentUnaryOperator.OperatorKind == testOperator);
ConstantValue constantLeft = loweredLeft.ConstantValue ?? UnboxConstant(loweredLeft);
if (testOperator == UnaryOperatorKind.DynamicFalse && constantLeft == ConstantValue.False ||
testOperator == UnaryOperatorKind.DynamicTrue && constantLeft == ConstantValue.True)
{
Debug.Assert(leftTruthOperator == null);
if (applyParentUnaryOperator != null)
{
// IsFalse(false && right) -> true
// IsTrue(true || right) -> true
return _factory.Literal(true);
}
else
{
// false && right -> box(false)
// true || right -> box(true)
return MakeConversionNode(loweredLeft, type, @checked: false);
}
}
BoundExpression result;
var boolean = _compilation.GetSpecialType(SpecialType.System_Boolean);
// Store left to local if needed. If constant or already local we don't need a temp
// since the value of left can't change until right is evaluated.
BoundAssignmentOperator tempAssignment;
BoundLocal temp;
if (constantLeft == null && loweredLeft.Kind != BoundKind.Local && loweredLeft.Kind != BoundKind.Parameter)
{
BoundAssignmentOperator assignment;
var local = _factory.StoreToTemp(loweredLeft, out assignment);
loweredLeft = local;
tempAssignment = assignment;
temp = local;
}
else
{
tempAssignment = null;
temp = null;
}
var op = _dynamicFactory.MakeDynamicBinaryOperator(operatorKind, loweredLeft, loweredRight, isCompoundAssignment, type).ToExpression();
// IsFalse(true) or IsTrue(false) are always false:
bool leftTestIsConstantFalse = testOperator == UnaryOperatorKind.DynamicFalse && constantLeft == ConstantValue.True ||
testOperator == UnaryOperatorKind.DynamicTrue && constantLeft == ConstantValue.False;
if (applyParentUnaryOperator != null)
{
// IsFalse(left && right) -> IsFalse(left) || IsFalse(And(left, right))
// IsTrue(left || right) -> IsTrue(left) || IsTrue(Or(left, right))
result = _dynamicFactory.MakeDynamicUnaryOperator(testOperator, op, boolean).ToExpression();
if (!leftTestIsConstantFalse)
{
BoundExpression leftTest = MakeTruthTestForDynamicLogicalOperator(syntax, loweredLeft, boolean, leftTruthOperator, negative: isAnd);
result = _factory.Binary(BinaryOperatorKind.LogicalOr, boolean, leftTest, result);
}
}
else
{
// left && right -> IsFalse(left) ? left : And(left, right)
// left || right -> IsTrue(left) ? left : Or(left, right)
if (leftTestIsConstantFalse)
{
result = op;
}
else
{
// We might need to box.
BoundExpression leftTest = MakeTruthTestForDynamicLogicalOperator(syntax, loweredLeft, boolean, leftTruthOperator, negative: isAnd);
var convertedLeft = MakeConversionNode(loweredLeft, type, @checked: false);
result = _factory.Conditional(leftTest, convertedLeft, op, type);
}
}
if (tempAssignment != null)
{
return _factory.Sequence(ImmutableArray.Create(temp.LocalSymbol), ImmutableArray.Create<BoundExpression>(tempAssignment), result);
}
return result;
}
public override BoundNode VisitUnaryOperator(BoundUnaryOperator node)
{
CheckUnsafeType(node);
CheckLiftedUnaryOp(node);
CheckDynamic(node);
return base.VisitUnaryOperator(node);
}
