/////////////////////////////////////////////////////////////////////////////////
// Expression types.
private ExprBinOp VisitBoundLambda(ExprBoundLambda anonmeth)
{
Debug.Assert(anonmeth != null);
MethodSymbol lambdaMethod = GetPreDefMethod(PREDEFMETH.PM_EXPRESSION_LAMBDA);
AggregateType delegateType = anonmeth.DelegateType;
TypeArray lambdaTypeParams = GetSymbolLoader().getBSymmgr().AllocParams(1, new CType[] { delegateType });
AggregateType expressionType = GetSymbolLoader().GetPredefindType(PredefinedType.PT_EXPRESSION);
MethWithInst mwi = new MethWithInst(lambdaMethod, expressionType, lambdaTypeParams);
Expr createParameters = CreateWraps(anonmeth);
Debug.Assert(createParameters != null);
Debug.Assert(anonmeth.Expression != null);
Expr body = Visit(anonmeth.Expression);
Debug.Assert(anonmeth.ArgumentScope.nextChild == null);
Expr parameters = GenerateParamsArray(null, PredefinedType.PT_PARAMETEREXPRESSION);
Expr args = GetExprFactory().CreateList(body, parameters);
CType typeRet = GetSymbolLoader().GetTypeManager().SubstType(mwi.Meth().RetType, mwi.GetType(), mwi.TypeArgs);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(null, mwi);
ExprCall call = GetExprFactory().CreateCall(0, typeRet, args, pMemGroup, mwi);
call.PredefinedMethod = PREDEFMETH.PM_EXPRESSION_LAMBDA;
return(GetExprFactory().CreateSequence(createParameters, call));
}
// Value
public Expr BindValue(Expr exprSrc)
{
Debug.Assert(exprSrc != null && exprSrc.Type is NullableType);
// For new T?(x), the answer is x.
if (IsNullableConstructor(exprSrc, out ExprCall call))
{
var args = call.OptionalArguments;
Debug.Assert(args != null && !(args is ExprList));
return(args);
}
NullableType nubSrc = (NullableType)exprSrc.Type;
CType typeBase = nubSrc.GetUnderlyingType();
AggregateType ats = nubSrc.GetAts();
PropertySymbol prop = GetSymbolLoader().getBSymmgr().propNubValue;
if (prop == null)
{
prop = GetSymbolLoader().getPredefinedMembers().GetProperty(PREDEFPROP.PP_G_OPTIONAL_VALUE);
Debug.Assert(prop != null);
GetSymbolLoader().getBSymmgr().propNubValue = prop;
}
PropWithType pwt = new PropWithType(prop, ats);
MethPropWithInst mpwi = new MethPropWithInst(prop, ats);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(exprSrc, mpwi);
return(GetExprFactory().CreateProperty(typeBase, null, null, pMemGroup, pwt, null));
}
public ExprProperty CreateProperty(CType pType, Expr pOptionalObject)
{
MethPropWithInst mwi = new MethPropWithInst();
ExprMemberGroup pMemGroup = CreateMemGroup(pOptionalObject, mwi);
return(CreateProperty(pType, null, null, pMemGroup, null, null, null));
}
public ExprMemberGroup CreateMemGroup(EXPRFLAG nFlags, Name pName, TypeArray pTypeArgs, SYMKIND symKind, CType pTypePar, MethodOrPropertySymbol pMPS, Expr pObject, CMemberLookupResults memberLookupResults)
{
Debug.Assert(0 == (nFlags & ~(
EXPRFLAG.EXF_CTOR | EXPRFLAG.EXF_INDEXER | EXPRFLAG.EXF_OPERATOR | EXPRFLAG.EXF_NEWOBJCALL |
EXPRFLAG.EXF_BASECALL | EXPRFLAG.EXF_DELEGATE | EXPRFLAG.EXF_USERCALLABLE | EXPRFLAG.EXF_MASK_ANY
)
));
ExprMemberGroup rval = new ExprMemberGroup();
rval.Kind = ExpressionKind.EK_MEMGRP;
rval.Type = GetTypes().GetMethGrpType();
rval.Flags = nFlags;
rval.name = pName;
rval.typeArgs = pTypeArgs;
rval.sk = symKind;
rval.ParentType = pTypePar;
rval.OptionalObject = pObject;
rval.MemberLookupResults = memberLookupResults;
rval.OptionalLHS = null;
if (rval.typeArgs == null)
{
rval.typeArgs = BSYMMGR.EmptyTypeArray();
}
Debug.Assert(rval != null);
return(rval);
}
public ExprCall(CType type, EXPRFLAG flags, Expr arguments, ExprMemberGroup member, MethWithInst method)
: base(ExpressionKind.Call, type)
{
Debug.Assert(
(flags & ~(EXPRFLAG.EXF_NEWOBJCALL | EXPRFLAG.EXF_CONSTRAINED
| EXPRFLAG.EXF_NEWSTRUCTASSG | EXPRFLAG.EXF_IMPLICITSTRUCTASSG | EXPRFLAG.EXF_MASK_ANY)) == 0);
Flags = flags;
OptionalArguments = arguments;
MemberGroup = member;
NullableCallLiftKind = NullableCallLiftKind.NotLifted;
MethWithInst = method;
}
// Create an expr for new T?(exprSrc) where T is exprSrc.type.
private static ExprCall BindNubNew(Expr exprSrc)
{
Debug.Assert(exprSrc != null);
NullableType pNubSourceType = TypeManager.GetNullable(exprSrc.Type);
AggregateType pSourceType = pNubSourceType.GetAts();
MethodSymbol meth = PredefinedMembers.GetMethod(PREDEFMETH.PM_G_OPTIONAL_CTOR);
MethWithInst methwithinst = new MethWithInst(meth, pSourceType, TypeArray.Empty);
ExprMemberGroup memgroup = ExprFactory.CreateMemGroup(null, methwithinst);
return(ExprFactory.CreateCall(EXPRFLAG.EXF_NEWOBJCALL | EXPRFLAG.EXF_CANTBENULL, pNubSourceType, exprSrc, memgroup, methwithinst));
}
private Expr GenerateDelegateInvoke(ExprCall expr)
{
Debug.Assert(expr != null);
ExprMemberGroup memberGroup = expr.MemberGroup;
Debug.Assert(memberGroup.IsDelegate);
Expr oldObject = memberGroup.OptionalObject;
Debug.Assert(oldObject != null);
Expr pObject = Visit(oldObject);
Expr args = GenerateArgsList(expr.OptionalArguments);
Expr Params = GenerateParamsArray(args, PredefinedType.PT_EXPRESSION);
return(GenerateCall(PREDEFMETH.PM_EXPRESSION_INVOKE, pObject, Params));
}
private ExprCall GenerateCall(PREDEFMETH pdm, Expr arg1, Expr arg2, Expr arg3, Expr arg4)
{
MethodSymbol method = GetPreDefMethod(pdm);
if (method == null)
{
return(null);
}
AggregateType expressionType = GetSymbolLoader().GetPredefindType(PredefinedType.PT_EXPRESSION);
Expr args = GetExprFactory().CreateList(arg1, arg2, arg3, arg4);
MethWithInst mwi = new MethWithInst(method, expressionType);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(null, mwi);
ExprCall call = GetExprFactory().CreateCall(0, mwi.Meth().RetType, args, pMemGroup, mwi);
call.PredefinedMethod = pdm;
return(call);
}
private ExprCall GenerateCall(PREDEFMETH pdm, Expr arg1)
{
MethodSymbol method = GetPreDefMethod(pdm);
// this should be enforced in an earlier pass and the transform pass should not
// be handling this error
if (method == null)
{
return(null);
}
AggregateType expressionType = GetSymbolLoader().GetPredefindType(PredefinedType.PT_EXPRESSION);
MethWithInst mwi = new MethWithInst(method, expressionType);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(null, mwi);
ExprCall call = GetExprFactory().CreateCall(0, mwi.Meth().RetType, arg1, pMemGroup, mwi);
call.PredefinedMethod = pdm;
return(call);
}
// Value
public Expr BindValue(Expr exprSrc)
{
Debug.Assert(exprSrc != null && exprSrc.Type.IsNullableType());
// For new T?(x), the answer is x.
if (IsNullableConstructor(exprSrc, out ExprCall call))
{
var args = call.OptionalArguments;
Debug.Assert(args != null && !(args is ExprList));
return(args);
}
CType typeBase = exprSrc.Type.AsNullableType().GetUnderlyingType();
AggregateType ats = exprSrc.Type.AsNullableType().GetAts(GetErrorContext());
if (ats == null)
{
ExprProperty rval = GetExprFactory().CreateProperty(typeBase, exprSrc);
rval.SetError();
return(rval);
}
PropertySymbol prop = GetSymbolLoader().getBSymmgr().propNubValue;
if (prop == null)
{
prop = GetSymbolLoader().getPredefinedMembers().GetProperty(PREDEFPROP.PP_G_OPTIONAL_VALUE);
GetSymbolLoader().getBSymmgr().propNubValue = prop;
}
PropWithType pwt = new PropWithType(prop, ats);
MethWithType mwt = new MethWithType(prop?.methGet, ats);
MethPropWithInst mpwi = new MethPropWithInst(prop, ats);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(exprSrc, mpwi);
ExprProperty exprRes = GetExprFactory().CreateProperty(typeBase, null, null, pMemGroup, pwt, mwt, null);
if (prop == null)
{
exprRes.SetError();
}
return(exprRes);
}
// If we have this.prop = 123, but the implementation of the property is in the
// base class, then the object is of the base class type. Note that to get
// the object, we must go through the MEMGRP.
//
// "throughObject" is
// of the type we are actually calling through. (We need to know the
// "through" type to ensure that protected semantics are correctly enforced.)
public ExprProperty(CType type, Expr pOptionalObjectThrough, Expr pOptionalArguments, ExprMemberGroup pMemberGroup, PropWithType pwtSlot, MethWithType mwtSet)
: base(ExpressionKind.Property, type)
{
OptionalObjectThrough = pOptionalObjectThrough;
OptionalArguments = pOptionalArguments;
MemberGroup = pMemberGroup;
if (pwtSlot != null)
{
PropWithTypeSlot = pwtSlot;
}
if (mwtSet != null)
{
MethWithTypeSet = mwtSet;
if (!HasIsExternalInitModifier(mwtSet))
{
Flags = EXPRFLAG.EXF_LVALUE;
}
}
}
public ExprCall BindNew(Expr pExprSrc)
{
Debug.Assert(pExprSrc != null);
NullableType pNubSourceType = GetSymbolLoader().GetTypeManager().GetNullable(pExprSrc.Type);
AggregateType pSourceType = pNubSourceType.GetAts();
MethodSymbol meth = GetSymbolLoader().getBSymmgr().methNubCtor;
if (meth == null)
{
meth = GetSymbolLoader().getPredefinedMembers().GetMethod(PREDEFMETH.PM_G_OPTIONAL_CTOR);
Debug.Assert(meth != null);
GetSymbolLoader().getBSymmgr().methNubCtor = meth;
}
MethWithInst methwithinst = new MethWithInst(meth, pSourceType, BSYMMGR.EmptyTypeArray());
ExprMemberGroup memgroup = GetExprFactory().CreateMemGroup(null, methwithinst);
return(GetExprFactory().CreateCall(EXPRFLAG.EXF_NEWOBJCALL | EXPRFLAG.EXF_CANTBENULL, pNubSourceType, pExprSrc, memgroup, methwithinst));
}
public ExprProperty CreateProperty(CType pType, Expr pOptionalObjectThrough, Expr pOptionalArguments, ExprMemberGroup pMemberGroup, PropWithType pwtSlot, MethWithType mwtGet, MethWithType mwtSet)
{
ExprProperty rval = new ExprProperty(pType);
rval.OptionalObjectThrough = pOptionalObjectThrough;
rval.OptionalArguments = pOptionalArguments;
rval.MemberGroup = pMemberGroup;
if (pwtSlot != null)
{
rval.PropWithTypeSlot = pwtSlot;
}
if (mwtSet != null)
{
rval.MethWithTypeSet = mwtSet;
}
return(rval);
}
protected override Expr VisitCALL(ExprCall expr)
{
Debug.Assert(expr != null);
switch (expr.NullableCallLiftKind)
{
default:
break;
case NullableCallLiftKind.NullableIntermediateConversion:
case NullableCallLiftKind.NullableConversion:
case NullableCallLiftKind.NullableConversionConstructor:
return(GenerateConversion(expr.OptionalArguments, expr.Type, expr.isChecked()));
case NullableCallLiftKind.NotLiftedIntermediateConversion:
case NullableCallLiftKind.UserDefinedConversion:
return(GenerateUserDefinedConversion(expr.OptionalArguments, expr.Type, expr.MethWithInst));
}
if (expr.MethWithInst.Meth().IsConstructor())
{
return(GenerateConstructor(expr));
}
ExprMemberGroup memberGroup = expr.MemberGroup;
if (memberGroup.IsDelegate)
{
return(GenerateDelegateInvoke(expr));
}
Expr pObject;
if (expr.MethWithInst.Meth().isStatic || expr.MemberGroup.OptionalObject == null)
{
pObject = GetExprFactory().CreateNull();
}
else
{
pObject = expr.MemberGroup.OptionalObject;
// If we have, say, an int? which is the object of a call to ToString
// then we do NOT want to generate ((object)i).ToString() because that
// will convert a null-valued int? to a null object. Rather what we want
// to do is box it to a ValueType and call ValueType.ToString.
//
// To implement this we say that if the object of the call is an implicit boxing cast
// then just generate the object, not the cast. If the cast is explicit in the
// source code then it will be an EXPLICITCAST and we will visit it normally.
//
// It might be better to rewrite the expression tree API so that it
// can handle in the general case all implicit boxing conversions. Right now it
// requires that all arguments to a call that need to be boxed be explicitly boxed.
if (pObject != null && pObject is ExprCast cast && cast.IsBoxingCast)
{
pObject = cast.Argument;
}
pObject = Visit(pObject);
}
Expr methodInfo = GetExprFactory().CreateMethodInfo(expr.MethWithInst);
Expr args = GenerateArgsList(expr.OptionalArguments);
Expr Params = GenerateParamsArray(args, PredefinedType.PT_EXPRESSION);
PREDEFMETH pdm = PREDEFMETH.PM_EXPRESSION_CALL;
Debug.Assert(!expr.MethWithInst.Meth().isVirtual || expr.MemberGroup.OptionalObject != null);
return(GenerateCall(pdm, pObject, methodInfo, Params));
}
public ExprProperty CreateProperty(CType pType, Expr pOptionalObjectThrough, Expr pOptionalArguments, ExprMemberGroup pMemberGroup, PropWithType pwtSlot, MethWithType mwtGet, MethWithType mwtSet)
{
ExprProperty rval = new ExprProperty();
rval.Kind = ExpressionKind.EK_PROP;
rval.Type = pType;
rval.Flags = 0;
rval.OptionalObjectThrough = pOptionalObjectThrough;
rval.OptionalArguments = pOptionalArguments;
rval.MemberGroup = pMemberGroup;
if (pwtSlot != null)
{
rval.PropWithTypeSlot = pwtSlot;
}
if (mwtSet != null)
{
rval.MethWithTypeSet = mwtSet;
}
Debug.Assert(rval != null);
return(rval);
}
/***************************************************************************************************
* Called by BindImplicitConversion when the destination type is Nullable<T>. The following
* conversions are handled by this method:
*
* For S in { object, ValueType, interfaces implemented by underlying type} there is an explicit
* unboxing conversion S => T?
* System.Enum => T? there is an unboxing conversion if T is an enum type
* null => T? implemented as default(T?)
*
* Implicit T?* => T?+ implemented by either wrapping or calling GetValueOrDefault the
* appropriate number of times.
* If imp/exp S => T then imp/exp S => T?+ implemented by converting to T then wrapping the
* appropriate number of times.
* If imp/exp S => T then imp/exp S?+ => T?+ implemented by calling GetValueOrDefault (m-1) times
* then calling HasValue, producing a null if it returns false, otherwise calling Value,
* converting to T then wrapping the appropriate number of times.
*
* The 3 rules above can be summarized with the following recursive rules:
*
* If imp/exp S => T? then imp/exp S? => T? implemented as
* qs.HasValue ? (T?)(qs.Value) : default(T?)
* If imp/exp S => T then imp/exp S => T? implemented as new T?((T)s)
*
* This method also handles calling bindUserDefinedConverion. This method does NOT handle
* the following conversions:
*
* Implicit boxing conversion from S? to { object, ValueType, Enum, ifaces implemented by S }. (Handled by BindImplicitConversion.)
* If imp/exp S => T then explicit S?+ => T implemented by calling Value the appropriate number
* of times. (Handled by BindExplicitConversion.)
*
* The recursive equivalent is:
*
* If imp/exp S => T and T is not nullable then explicit S? => T implemented as qs.Value
*
* Some nullable conversion are NOT standard conversions. In particular, if S => T is implicit
* then S? => T is not standard. Similarly if S => T is not implicit then S => T? is not standard.
***************************************************************************************************/
private bool BindNubConversion(NullableType nubDst)
{
// This code assumes that STANDARD and ISEXPLICIT are never both set.
// bindUserDefinedConversion should ensure this!
Debug.Assert(0 != (~_flags & (CONVERTTYPE.STANDARD | CONVERTTYPE.ISEXPLICIT)));
Debug.Assert(_exprSrc == null || _exprSrc.Type == _typeSrc);
Debug.Assert(!_needsExprDest || _exprSrc != null);
Debug.Assert(_typeSrc != nubDst); // BindImplicitConversion should have taken care of this already.
AggregateType atsDst = nubDst.GetAts();
// Check for the unboxing conversion. This takes precedence over the wrapping conversions.
if (GetSymbolLoader().HasBaseConversion(nubDst.GetUnderlyingType(), _typeSrc) && !CConversions.FWrappingConv(_typeSrc, nubDst))
{
// These should be different! Fix the caller if typeSrc is an AggregateType of Nullable.
Debug.Assert(atsDst != _typeSrc);
// typeSrc is a base type of the destination nullable type so there is an explicit
// unboxing conversion.
if (0 == (_flags & CONVERTTYPE.ISEXPLICIT))
{
return(false);
}
if (_needsExprDest)
{
_binder.bindSimpleCast(_exprSrc, _typeDest, out _exprDest, EXPRFLAG.EXF_UNBOX);
}
return(true);
}
bool dstWasNullable;
bool srcWasNullable;
CType typeDstBase = nubDst.StripNubs(out dstWasNullable);
CType typeSrcBase = _typeSrc.StripNubs(out srcWasNullable);
ConversionFunc pfn = (_flags & CONVERTTYPE.ISEXPLICIT) != 0 ?
(ConversionFunc)_binder.BindExplicitConversion :
(ConversionFunc)_binder.BindImplicitConversion;
if (!srcWasNullable)
{
Debug.Assert(_typeSrc == typeSrcBase);
// The null type can be implicitly converted to T? as the default value.
if (_typeSrc is NullType)
{
// If we have the constant null, generate it as a default value of T?. If we have
// some crazy expression which has been determined to be always null, like (null??null)
// keep it in its expression form and transform it in the nullable rewrite pass.
if (_needsExprDest)
{
if (_exprSrc.isCONSTANT_OK())
{
_exprDest = GetExprFactory().CreateZeroInit(nubDst);
}
else
{
_exprDest = GetExprFactory().CreateCast(_typeDest, _exprSrc);
}
}
return(true);
}
Expr exprTmp = _exprSrc;
// If there is an implicit/explicit S => T then there is an implicit/explicit S => T?
if (_typeSrc == typeDstBase || pfn(_exprSrc, _typeSrc, typeDstBase, _needsExprDest, out exprTmp, _flags | CONVERTTYPE.NOUDC))
{
if (_needsExprDest)
{
ExprUserDefinedConversion exprUDC = exprTmp as ExprUserDefinedConversion;
if (exprUDC != null)
{
exprTmp = exprUDC.UserDefinedCall;
}
if (dstWasNullable)
{
ExprCall call = _binder.BindNubNew(exprTmp);
exprTmp = call;
call.NullableCallLiftKind = NullableCallLiftKind.NullableConversionConstructor;
}
if (exprUDC != null)
{
exprUDC.UserDefinedCall = exprTmp;
exprTmp = exprUDC;
}
Debug.Assert(exprTmp.Type == nubDst);
_exprDest = exprTmp;
}
return(true);
}
// No builtin conversion. Maybe there is a user defined conversion....
return(0 == (_flags & CONVERTTYPE.NOUDC) && _binder.bindUserDefinedConversion(_exprSrc, _typeSrc, nubDst, _needsExprDest, out _exprDest, 0 == (_flags & CONVERTTYPE.ISEXPLICIT)));
}
// Both are Nullable so there is only a conversion if there is a conversion between the base types.
// That is, if there is an implicit/explicit S => T then there is an implicit/explicit S?+ => T?+.
if (typeSrcBase != typeDstBase && !pfn(null, typeSrcBase, typeDstBase, false, out _exprDest, _flags | CONVERTTYPE.NOUDC))
{
// No builtin conversion. Maybe there is a user defined conversion....
return(0 == (_flags & CONVERTTYPE.NOUDC) && _binder.bindUserDefinedConversion(_exprSrc, _typeSrc, nubDst, _needsExprDest, out _exprDest, 0 == (_flags & CONVERTTYPE.ISEXPLICIT)));
}
if (_needsExprDest)
{
MethWithInst mwi = new MethWithInst(null, null);
ExprMemberGroup pMemGroup = GetExprFactory().CreateMemGroup(null, mwi);
ExprCall exprDst = GetExprFactory().CreateCall(0, nubDst, _exprSrc, pMemGroup, null);
// Here we want to first check whether or not the conversions work on the base types.
Expr arg1 = _binder.mustCast(_exprSrc, typeSrcBase);
bool convertible = (_flags & CONVERTTYPE.ISEXPLICIT) != 0
? _binder.BindExplicitConversion(
arg1, arg1.Type, typeDstBase, out arg1, _flags | CONVERTTYPE.NOUDC)
: _binder.BindImplicitConversion(
arg1, arg1.Type, typeDstBase, out arg1, _flags | CONVERTTYPE.NOUDC);
if (!convertible)
{
Debug.Fail("bind(Im|Ex)plicitConversion failed unexpectedly");
return(false);
}
exprDst.CastOfNonLiftedResultToLiftedType = _binder.mustCast(arg1, nubDst, 0);
exprDst.NullableCallLiftKind = NullableCallLiftKind.NullableConversion;
exprDst.PConversions = exprDst.CastOfNonLiftedResultToLiftedType;
_exprDest = exprDst;
}
return(true);
}
protected virtual Expr VisitMEMGRP(ExprMemberGroup pExpr)
{
return(VisitEXPR(pExpr));
}
public static ExprProperty CreateProperty(CType type, Expr optionalObjectThrough, Expr arguments, ExprMemberGroup memberGroup, PropWithType property, MethWithType setMethod) => new ExprProperty(type, optionalObjectThrough, arguments, memberGroup, property, setMethod);
public static ExprCall CreateCall(EXPRFLAG flags, CType type, Expr arguments, ExprMemberGroup memberGroup, MethWithInst method) => new ExprCall(type, flags, arguments, memberGroup, method);
public ExprCall CreateCall(EXPRFLAG nFlags, CType pType, Expr pOptionalArguments, ExprMemberGroup pMemberGroup, MethWithInst MWI)
{
Debug.Assert(0 == (nFlags &
~(
EXPRFLAG.EXF_NEWOBJCALL | EXPRFLAG.EXF_CONSTRAINED | EXPRFLAG.EXF_BASECALL |
EXPRFLAG.EXF_NEWSTRUCTASSG |
EXPRFLAG.EXF_IMPLICITSTRUCTASSG | EXPRFLAG.EXF_MASK_ANY
)
));
ExprCall rval = new ExprCall();
rval.Kind = ExpressionKind.EK_CALL;
rval.Type = pType;
rval.Flags = nFlags;
rval.OptionalArguments = pOptionalArguments;
rval.MemberGroup = pMemberGroup;
rval.NullableCallLiftKind = NullableCallLiftKind.NotLifted;
rval.CastOfNonLiftedResultToLiftedType = null;
rval.MethWithInst = MWI;
Debug.Assert(rval != null);
return(rval);
}
