OverloadResolutionErrors IsUnambiguousCall(ExpectedTargetDetails expectedTargetDetails, IMethod method,
ResolveResult target, IType[] typeArguments, IList <TranslatedExpression> arguments,
string[] argumentNames,
out IParameterizedMember foundMember)
{
foundMember = null;
var lookup = new MemberLookup(resolver.CurrentTypeDefinition, resolver.CurrentTypeDefinition.ParentAssembly);
var or = new OverloadResolution(resolver.Compilation,
arguments.SelectArray(a => a.ResolveResult),
argumentNames: argumentNames,
typeArguments: typeArguments,
conversions: expressionBuilder.resolver.conversions);
if (expectedTargetDetails.CallOpCode == OpCode.NewObj)
{
foreach (IMethod ctor in method.DeclaringType.GetConstructors())
{
if (lookup.IsAccessible(ctor, allowProtectedAccess: resolver.CurrentTypeDefinition == method.DeclaringTypeDefinition))
{
or.AddCandidate(ctor);
}
}
}
else if (target == null)
{
var result = resolver.ResolveSimpleName(method.Name, typeArguments, isInvocationTarget: true) as MethodGroupResolveResult;
if (result == null)
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
or.AddMethodLists(result.MethodsGroupedByDeclaringType.ToArray());
}
else
{
var result = lookup.Lookup(target, method.Name, EmptyList <IType> .Instance, isInvocation: true) as MethodGroupResolveResult;
if (result == null)
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
or.AddMethodLists(result.MethodsGroupedByDeclaringType.ToArray());
}
if (or.BestCandidateErrors != OverloadResolutionErrors.None)
{
return(or.BestCandidateErrors);
}
if (or.IsAmbiguous)
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
foundMember = or.GetBestCandidateWithSubstitutedTypeArguments();
if (!IsAppropriateCallTarget(expectedTargetDetails, method, foundMember))
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
return(OverloadResolutionErrors.None);
}
public OverloadResolution PerformOverloadResolution(ICompilation compilation, Expression[] arguments, string[] argumentNames = null,
bool allowExtensionMethods = true,
bool allowExpandingParams = true,
bool allowOptionalParameters = true,
bool checkForOverflow = false, VSharpConversions conversions = null)
{
var typeArgumentArray = this.TypeArguments.ToArray();
OverloadResolution or = new OverloadResolution(compilation, arguments, argumentNames, typeArgumentArray, conversions);
or.AllowExpandingParams = allowExpandingParams;
or.AllowOptionalParameters = allowOptionalParameters;
or.CheckForOverflow = checkForOverflow;
or.AddMethodLists(methodLists);
if (allowExtensionMethods && !or.FoundApplicableCandidate)
{
// No applicable match found, so let's try extension methods.
var extensionMethods = this.GetExtensionMethods();
if (extensionMethods.Any())
{
Expression[] extArguments = new Expression[arguments.Length + 1];
extArguments[0] = new AST.Expression(this.TargetType);
arguments.CopyTo(extArguments, 1);
string[] extArgumentNames = null;
if (argumentNames != null)
{
extArgumentNames = new string[argumentNames.Length + 1];
argumentNames.CopyTo(extArgumentNames, 1);
}
var extOr = new OverloadResolution(compilation, extArguments, extArgumentNames, typeArgumentArray, conversions);
extOr.AllowExpandingParams = allowExpandingParams;
extOr.AllowOptionalParameters = allowOptionalParameters;
extOr.IsExtensionMethodInvocation = true;
extOr.CheckForOverflow = checkForOverflow;
foreach (var g in extensionMethods)
{
foreach (var method in g)
extOr.AddCandidate(method);
if (extOr.FoundApplicableCandidate)
break;
}
// For the lack of a better comparison function (the one within OverloadResolution
// cannot be used as it depends on the argument set):
if (extOr.FoundApplicableCandidate || or.BestCandidate == null)
{
// Consider an extension method result better than the normal result only
// if it's applicable; or if there is no normal result.
or = extOr;
}
}
}
return or;
}
OverloadResolutionErrors IsUnambiguousCall(ILInstruction inst, TranslatedExpression target, IMethod method, IType[] typeArguments, IList <TranslatedExpression> arguments)
{
var lookup = new MemberLookup(resolver.CurrentTypeDefinition, resolver.CurrentTypeDefinition.ParentAssembly);
var or = new OverloadResolution(resolver.Compilation, arguments.SelectArray(a => a.ResolveResult), typeArguments: typeArguments);
if (inst is NewObj newObj)
{
foreach (IMethod ctor in newObj.Method.DeclaringType.GetConstructors())
{
if (lookup.IsAccessible(ctor, allowProtectedAccess: resolver.CurrentTypeDefinition == newObj.Method.DeclaringTypeDefinition))
{
or.AddCandidate(ctor);
}
}
}
else
{
var result = lookup.Lookup(target.ResolveResult, method.Name, EmptyList <IType> .Instance, true) as MethodGroupResolveResult;
if (result == null)
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
or.AddMethodLists(result.MethodsGroupedByDeclaringType.ToArray());
}
if (or.BestCandidateErrors != OverloadResolutionErrors.None)
{
return(or.BestCandidateErrors);
}
if (!IsAppropriateCallTarget(method, or.GetBestCandidateWithSubstitutedTypeArguments(), inst.OpCode == OpCode.CallVirt))
{
return(OverloadResolutionErrors.AmbiguousMatch);
}
return(OverloadResolutionErrors.None);
}
TranslatedExpression HandleDelegateConstruction(CallInstruction inst)
{
ILInstruction func = inst.Arguments[1];
IMethod method;
switch (func.OpCode)
{
case OpCode.LdFtn:
method = ((LdFtn)func).Method;
break;
case OpCode.LdVirtFtn:
method = ((LdVirtFtn)func).Method;
break;
default:
method = (IMethod)typeSystem.Resolve(((ILFunction)func).Method);
break;
}
var target = expressionBuilder.TranslateTarget(method, inst.Arguments[0], func.OpCode == OpCode.LdFtn);
var lookup = new MemberLookup(resolver.CurrentTypeDefinition, resolver.CurrentTypeDefinition.ParentAssembly);
var or = new OverloadResolution(resolver.Compilation, method.Parameters.SelectArray(p => new TypeResolveResult(p.Type)));
var result = lookup.Lookup(target.ResolveResult, method.Name, method.TypeArguments, true) as MethodGroupResolveResult;
if (result == null)
{
target = target.ConvertTo(method.DeclaringType, expressionBuilder);
}
else
{
or.AddMethodLists(result.MethodsGroupedByDeclaringType.ToArray());
if (or.BestCandidateErrors != OverloadResolutionErrors.None || !IsAppropriateCallTarget(method, or.BestCandidate, func.OpCode == OpCode.LdVirtFtn))
{
target = target.ConvertTo(method.DeclaringType, expressionBuilder);
}
}
var mre = new MemberReferenceExpression(target, method.Name);
mre.TypeArguments.AddRange(method.TypeArguments.Select(expressionBuilder.ConvertType));
var oce = new ObjectCreateExpression(expressionBuilder.ConvertType(inst.Method.DeclaringType), mre)
// .WithAnnotation(new DelegateConstruction.Annotation(func.OpCode == OpCode.LdVirtFtn, target, method.Name))
.WithILInstruction(inst)
.WithRR(new ConversionResolveResult(
inst.Method.DeclaringType,
new MemberResolveResult(target.ResolveResult, method),
// TODO handle extension methods capturing the first argument
Conversion.MethodGroupConversion(method, func.OpCode == OpCode.LdVirtFtn, false)));
if (func is ILFunction)
{
return(expressionBuilder.TranslateFunction(oce, target, (ILFunction)func));
}
else
{
return(oce);
}
}
/// <summary>
/// Resolves an indexer access.
/// </summary>
/// <param name="target">Target expression.</param>
/// <param name="arguments">
/// Arguments passed to the indexer.
/// The resolver may mutate this array to wrap elements in <see cref="CastExpression"/>s!
/// </param>
/// <param name="argumentNames">
/// The argument names. Pass the null string for positional arguments.
/// </param>
/// <returns>ArrayAccessResolveResult, InvocationResolveResult, or ErrorResolveResult</returns>
public Expression ResolveIndexer(ResolveContext rc, Expression target, Expression[] arguments, string[] argumentNames = null)
{
switch (target.Type.Kind)
{
case TypeKind.Array:
// �6.6.1 Array access
if (argumentNames != null && argumentNames.Length > 0)
{
rc.Report.Error(0, Arguments.args.Where(x => x is NamedArgument).First().loc, "An element access expression cannot use named argument");
}
return(new ArrayAccessExpression(((ElementTypeSpec)target.Type).ElementType, target, arguments));
case TypeKind.Pointer:
// �.5.3 Pointer element access
if (argumentNames != null && argumentNames.Length > 0)
{
rc.Report.Error(0, Arguments.args.Where(x => x is NamedArgument).First().loc, "An element access expression cannot use named argument");
}
return(new PointerArithmeticExpression(((ElementTypeSpec)target.Type).ElementType, target, arguments));
}
// �6.6.2 Indexer access
MemberLookup lookup = rc.CreateMemberLookup();
var indexers = lookup.LookupIndexers(target);
OverloadResolution or = rc.CreateOverloadResolution(arguments, argumentNames);
or.AddMethodLists(indexers);
if (or.BestCandidate != null)
{
return(or.CreateInvocation(target));
}
else
{
rc.Report.Error(0, loc, "Cannot apply indexing with [] to an expression of type `{0}'",
target.Type.ToString());
return(null);
}
}
TranslatedExpression HandleDelegateConstruction(CallInstruction inst)
{
ILInstruction func = inst.Arguments[1];
IMethod method;
switch (func.OpCode)
{
case OpCode.LdFtn:
method = ((LdFtn)func).Method;
break;
case OpCode.LdVirtFtn:
method = ((LdVirtFtn)func).Method;
break;
default:
throw new ArgumentException($"Unknown instruction type: {func.OpCode}");
}
var invokeMethod = inst.Method.DeclaringType.GetDelegateInvokeMethod();
TranslatedExpression target;
IType targetType;
if (method.IsExtensionMethod && invokeMethod != null && method.Parameters.Count - 1 == invokeMethod.Parameters.Count)
{
target = expressionBuilder.Translate(inst.Arguments[0]);
targetType = method.Parameters[0].Type;
}
else
{
target = expressionBuilder.TranslateTarget(method, inst.Arguments[0], func.OpCode == OpCode.LdFtn);
targetType = method.DeclaringType;
}
var lookup = new MemberLookup(resolver.CurrentTypeDefinition, resolver.CurrentTypeDefinition.ParentAssembly);
var or = new OverloadResolution(resolver.Compilation, method.Parameters.SelectArray(p => new TypeResolveResult(p.Type)));
var result = lookup.Lookup(target.ResolveResult, method.Name, method.TypeArguments, false);
bool needsCast = true;
if (result is MethodGroupResolveResult mgrr)
{
or.AddMethodLists(mgrr.MethodsGroupedByDeclaringType.ToArray());
var expectedTargetDetails = new ExpectedTargetDetails {
CallOpCode = inst.OpCode
};
needsCast = (or.BestCandidateErrors != OverloadResolutionErrors.None || !IsAppropriateCallTarget(expectedTargetDetails, method, or.BestCandidate));
}
if (needsCast)
{
target = target.ConvertTo(targetType, expressionBuilder);
result = lookup.Lookup(target.ResolveResult, method.Name, method.TypeArguments, false);
}
var mre = new MemberReferenceExpression(target, method.Name);
mre.TypeArguments.AddRange(method.TypeArguments.Select(expressionBuilder.ConvertType));
mre.WithRR(result);
var oce = new ObjectCreateExpression(expressionBuilder.ConvertType(inst.Method.DeclaringType), mre)
.WithILInstruction(inst)
.WithRR(new ConversionResolveResult(
inst.Method.DeclaringType,
new MemberResolveResult(target.ResolveResult, method),
Conversion.MethodGroupConversion(method, func.OpCode == OpCode.LdVirtFtn, false)));
return(oce);
}
TranslatedExpression HandleDelegateConstruction(CallInstruction inst)
{
ILInstruction func = inst.Arguments[1];
IMethod method;
switch (func.OpCode)
{
case OpCode.LdFtn:
method = ((LdFtn)func).Method;
break;
case OpCode.LdVirtFtn:
method = ((LdVirtFtn)func).Method;
break;
default:
throw new ArgumentException($"Unknown instruction type: {func.OpCode}");
}
var invokeMethod = inst.Method.DeclaringType.GetDelegateInvokeMethod();
TranslatedExpression target;
IType targetType;
bool requireTarget;
if (method.IsExtensionMethod && invokeMethod != null && method.Parameters.Count - 1 == invokeMethod.Parameters.Count)
{
targetType = method.Parameters[0].Type;
target = expressionBuilder.Translate(inst.Arguments[0], targetType);
target = ExpressionBuilder.UnwrapBoxingConversion(target);
requireTarget = true;
}
else
{
targetType = method.DeclaringType;
target = expressionBuilder.TranslateTarget(method, inst.Arguments[0], func.OpCode == OpCode.LdFtn);
target = ExpressionBuilder.UnwrapBoxingConversion(target);
requireTarget = expressionBuilder.HidesVariableWithName(method.Name) ||
(method.IsStatic ? !expressionBuilder.IsCurrentOrContainingType(method.DeclaringTypeDefinition) : !(target.Expression is ThisReferenceExpression));
}
var expectedTargetDetails = new ExpectedTargetDetails {
CallOpCode = inst.OpCode
};
bool needsCast = false;
ResolveResult result = null;
var or = new OverloadResolution(resolver.Compilation, method.Parameters.SelectArray(p => new TypeResolveResult(p.Type)));
if (!requireTarget)
{
result = resolver.ResolveSimpleName(method.Name, method.TypeArguments, isInvocationTarget: false);
if (result is MethodGroupResolveResult mgrr)
{
or.AddMethodLists(mgrr.MethodsGroupedByDeclaringType.ToArray());
requireTarget = (or.BestCandidateErrors != OverloadResolutionErrors.None || !IsAppropriateCallTarget(expectedTargetDetails, method, or.BestCandidate));
}
else
{
requireTarget = true;
}
}
MemberLookup lookup = null;
if (requireTarget)
{
lookup = new MemberLookup(resolver.CurrentTypeDefinition, resolver.CurrentTypeDefinition.ParentAssembly);
var rr = lookup.Lookup(target.ResolveResult, method.Name, method.TypeArguments, false);
needsCast = true;
result = rr;
if (rr is MethodGroupResolveResult mgrr)
{
or.AddMethodLists(mgrr.MethodsGroupedByDeclaringType.ToArray());
needsCast = (or.BestCandidateErrors != OverloadResolutionErrors.None || !IsAppropriateCallTarget(expectedTargetDetails, method, or.BestCandidate));
}
}
if (needsCast)
{
Debug.Assert(requireTarget);
target = target.ConvertTo(targetType, expressionBuilder);
result = lookup.Lookup(target.ResolveResult, method.Name, method.TypeArguments, false);
}
Expression targetExpression;
if (requireTarget)
{
var mre = new MemberReferenceExpression(target, method.Name);
mre.TypeArguments.AddRange(method.TypeArguments.Select(expressionBuilder.ConvertType));
mre.WithRR(result);
targetExpression = mre;
}
else
{
var ide = new IdentifierExpression(method.Name)
.WithRR(result);
targetExpression = ide;
}
var oce = new ObjectCreateExpression(expressionBuilder.ConvertType(inst.Method.DeclaringType), targetExpression)
.WithILInstruction(inst)
.WithRR(new ConversionResolveResult(
inst.Method.DeclaringType,
new MemberResolveResult(target.ResolveResult, method),
Conversion.MethodGroupConversion(method, func.OpCode == OpCode.LdVirtFtn, false)));
return(oce);
}
