private static bool IsSpecPublic(Field f)
{
// F:
Contract.Requires(f != null);
return f.Attributes.HasAttribute(ContractNodes.SpecPublicAttributeName);
}
/// <summary>
/// Find shadow field in given type corresponding to field.
/// </summary>
public static Field FindShadow(this TypeNode parent, Field field)
{
if (field == null || field.Name == null)
{
return null;
}
MemberList members = parent.GetMembersNamed(field.Name);
for (int i = 0, n = members == null ? 0 : members.Count; i < n; i++)
{
Field f = members[i] as Field;
if (f != null) return f;
}
return null;
}
private Field GetReturnValueClosureField(TypeNode declaringType, TypeNode resultType, FieldFlags flags, int uniqueKey)
{
Contract.Requires(declaringType != null);
Contract.Assume(declaringType.Template == null);
Identifier name = Identifier.For("_result" + uniqueKey.ToString()); // unique name for this field
Field f = declaringType.GetField(name);
if (f != null) return f;
f = new Field(declaringType,
null,
flags,
name,
resultType,
null);
declaringType.Members.Add(f);
// remember we added it so we can make it part of initializations
if (f.IsStatic)
{
topLevelStaticResultField = f;
}
else
{
topLevelClosureResultField = f;
}
return f;
}
public static List<int> FieldElementsPeerPositions(Field f)
{
List<int> res = new List<int>();
if (f == null) return res;
AttributeList al = f.GetAllAttributes(SystemTypes.ElementsPeerAttribute);
if (al == null) return res;
foreach (AttributeNode attr in al)
{
ExpressionList exprs = attr.Expressions;
int value = -10;
if (exprs == null || exprs.Count == 0)
value = -1; // default value for attribute w/o param
else
{
Expression arg = exprs[0];
Literal lit = arg as Literal;
if (lit != null && lit.Value is int)
value = (int)lit.Value;
}
if (value == -1) // all positions are ElementsPeer
{
return ElementsPositions(f.Type);
}
else // a specific type argument is ElementsPeer
{
res.Add(value);
}
}
return res;
}
public override void VisitField(Field field)
{
base.VisitField(field);
var type = HelperMethods.Unspecialize(field.Type);
if (type == contractClass)
{
if (field.Type.TemplateArguments != null)
{
var inst = this.OriginalType.GetTemplateInstance(field.Type, field.Type.TemplateArguments);
field.Type = inst;
}
else
{
field.Type = this.OriginalType;
}
}
}
private static string GetFieldQualifiers(Field field)
{
string qualifiers = string.Empty;
if (field.IsStatic)
qualifiers += "static ";
return qualifiers;
}
public override void VisitField(Field field)
{
if (field == null) return;
this.CheckField(field);
}
private void PrepareGuardedClass(TypeNode typeNode) {
SpecSharpCompilerOptions options = this.currentOptions as SpecSharpCompilerOptions;
if (!(options != null && (options.DisableGuardedClassesChecks || options.Compatibility))) {
if (typeNode is Class && typeNode.Contract != null && (typeNode.Contract.InvariantCount > 0 || typeNode.Contract.ModelfieldContractCount > 0) ||
typeNode is Class && this.currentPreprocessorDefinedSymbols != null && this.currentPreprocessorDefinedSymbols.ContainsKey("GuardAllClasses")) {
if (typeNode.Interfaces == null) {
typeNode.Interfaces = new InterfaceList();
}
if (typeNode.Template == null) { //we have to be careful when we are passed a typeNode of a specialized generic type as it shares the contract of the 'real' generic typeNode
#region Add the field "frame" to the class.
Field frameField = new Field(typeNode, null, FieldFlags.Public, Identifier.For("SpecSharp::frameGuard"), SystemTypes.Guard, null);
frameField.CciKind = CciMemberKind.Auxiliary;
typeNode.Contract.FrameField = frameField;
typeNode.Members.Add(frameField);
This thisParameter = new This(typeNode);
Method frameGetter = new Method(typeNode, NoDefaultExpose(), Identifier.For("get_SpecSharp::FrameGuard"), null, OptionalModifier.For(SystemTypes.NonNullType, SystemTypes.Guard),
new Block(new StatementList(new Return(new BinaryExpression(new MemberBinding(thisParameter, frameField), new Literal(SystemTypes.NonNullType, SystemTypes.Type), System.Compiler.NodeType.ExplicitCoercion, OptionalModifier.For(SystemTypes.NonNullType, SystemTypes.Guard))))));
// Pretend this method is [Delayed] so that we can call it from a delayed constructor.
frameGetter.Attributes.Add(new AttributeNode(new Literal(ExtendedRuntimeTypes.DelayedAttribute, SystemTypes.Type), null, AttributeTargets.Method));
frameGetter.CciKind = CciMemberKind.FrameGuardGetter;
frameGetter.Attributes.Add(new AttributeNode(new Literal(SystemTypes.PureAttribute, SystemTypes.Type), null, AttributeTargets.Method));
frameGetter.Flags = MethodFlags.Public | MethodFlags.HideBySig | MethodFlags.SpecialName;
frameGetter.CallingConvention = CallingConventionFlags.HasThis;
frameGetter.ThisParameter = thisParameter;
typeNode.Contract.FramePropertyGetter = frameGetter;
typeNode.Members.Add(frameGetter);
Property frameProperty = new Property(typeNode, null, PropertyFlags.None, Identifier.For("SpecSharp::FrameGuard"), frameGetter, null);
typeNode.Members.Add(frameProperty);
typeNode.Contract.FrameProperty = frameProperty;
#endregion
typeNode.Contract.InitFrameSetsMethod = new Method(typeNode, NoDefaultExpose(), Identifier.For("SpecSharp::InitGuardSets"), null, SystemTypes.Void, null);
typeNode.Contract.InitFrameSetsMethod.CciKind = CciMemberKind.Auxiliary;
typeNode.Contract.InitFrameSetsMethod.Flags = MethodFlags.Public | MethodFlags.HideBySig | MethodFlags.SpecialName;
}
}
}
}
internal static void TryAddDebuggerBrowsableNeverAttribute(Field field)
{
Contract.Requires(field != null);
TryAddDebuggerBrowsableNeverAttribute(field, System.AttributeTargets.Field);
}
private static bool FieldAssociatedWithParameter(Field field, Method originalMethod, out Parameter p)
{
string fname = field.Name.Name;
if (fname.EndsWith("__this"))
{
// check that it is not a nested one
if (fname.Length > 8 && !fname.Substring(2, fname.Length - 8).Contains("__"))
{
p = originalMethod.ThisParameter;
return true;
}
}
foreach (Parameter par in originalMethod.Parameters)
{
string pname = par.Name.Name;
if (fname == pname)
{
p = par;
return true;
}
}
p = null;
return false;
}
public static bool IsClosureField(TypeNode container, Field field)
{
Contract.Requires(container != null);
Contract.Requires(field != null);
var type = Unspecialize(field.DeclaringType);
if (IsClosureType(container, type)) return true;
// can be a direct member of a type inside container for caching delegates
if (!field.IsPrivate) return false;
if (!(field.Type.IsDelegateType())) return false;
if (!IsInsideOf(field, container)) return false;
if (!IsCompilerGenerated(field)) return false;
return true;
}
bool IsAccessibleFrom(Field field, Method from)
{
}
public override Expression VisitLocal(Local local)
{
if (HelperMethods.IsClosureType(this.declaringType, local.Type))
{
MemberBinding mb;
if (!closureLocals.TryGetValue(local, out mb))
{
// Forwarder would be null, if enclosing method with async closure is not generic
var localType = forwarder != null ? forwarder.VisitTypeReference(local.Type) : local.Type;
var closureField = new Field(this.closureClass, null, FieldFlags.Public, local.Name, localType, null);
this.closureClass.Members.Add(closureField);
mb = new MemberBinding(this.checkMethod.ThisParameter, closureField);
closureLocals.Add(local, mb);
// initialize the closure field
var instantiatedField = GetMemberInstanceReference(closureField, this.closureClassInstance);
this.ClosureInitializer.Statements.Add(new AssignmentStatement(new MemberBinding(this.ClosureLocal, instantiatedField), local));
}
return mb;
}
return local;
}
private static Expression CreateProperResultAccess(ReturnValue returnValue, Expression closureObject, Field resultField)
{
Contract.Requires(returnValue != null);
Contract.Requires(resultField != null);
var fieldAccess = new MemberBinding(closureObject, resultField);
if (resultField.Type != returnValue.Type)
{
// must cast to generic type expected in this context (box instance unbox.any Generic)
return new BinaryExpression(new BinaryExpression(fieldAccess, new Literal(resultField.Type), NodeType.Box), new Literal(returnValue.Type), NodeType.UnboxAny);
}
else
{
return fieldAccess;
}
}
private Method FindAndInstantiateBaseClassInvariantMethod(Class asClass, out Field baseReentrancyFlag)
{
baseReentrancyFlag = null;
if (asClass == null || asClass.BaseClass == null) return null;
if (!this.Emit(RuntimeContractEmitFlags.InheritContracts)) return null; // don't call base class invariant if we don't inherit
var baseClass = asClass.BaseClass;
if (!this.InheritInvariantsAcrossAssemblies && (baseClass.DeclaringModule != asClass.DeclaringModule))
return null;
var result = baseClass.GetMethod(Identifier.For("$InvariantMethod$"), null);
if (result != null && !HelperMethods.IsVisibleFrom(result, asClass)) return null;
if (result == null && baseClass.Template != null)
{
// instantiation of generated method has not happened.
var generic = baseClass.Template.GetMethod(Identifier.For("$InvariantMethod$"), null);
if (generic != null)
{
if (!HelperMethods.IsVisibleFrom(generic, asClass)) return null;
// generate proper reference.
result = GetMethodInstanceReference(generic, baseClass);
}
}
// extract base reentrancy flag
if (result != null) {
var instantiatedParent = result.DeclaringType;
baseReentrancyFlag = instantiatedParent.GetField(Identifier.For("$evaluatingInvariant$"));
if (baseReentrancyFlag == null && baseClass.Template != null)
{
// instantiation of generated baseReentrancy flag has not happened.
var generic = baseClass.Template.GetField(Identifier.For("$evaluatingInvariant$"));
if (generic != null)
{
if (HelperMethods.IsVisibleFrom(generic, asClass))
{
baseReentrancyFlag = GetFieldInstanceReference(generic, baseClass);
}
}
}
}
return result;
}
public override void VisitTypeNode(TypeNode typeNode) {
if (typeNode == null) return;
if (HelperMethods.IsContractTypeForSomeOtherType(typeNode, this.rewriterNodes) != null) {
return;
}
Method savedInvariantMethod = this.InvariantMethod;
Field savedReentrancyFlag = this.ReentrancyFlag;
this.InvariantMethod = null;
this.ReentrancyFlag = null;
var savedState = this.currentState;
this.currentState = new CurrentState(typeNode);
var savedEmitFlags = this.AdaptRuntimeOptionsBasedOnAttributes(typeNode.Attributes);
try
{
if (this.Emit(RuntimeContractEmitFlags.Invariants) && rewriterNodes.InvariantMethod != null)
{
InvariantList userWrittenInvariants = typeNode.Contract == null ? null : typeNode.Contract.Invariants;
Class asClass = typeNode as Class;
Field baseReentrancyFlag;
Method baseInvariantMethod = FindAndInstantiateBaseClassInvariantMethod(asClass, out baseReentrancyFlag);
if ((userWrittenInvariants != null && 0 < userWrittenInvariants.Count) || baseInvariantMethod != null)
{
Field reEntrancyFlag = null;
var isStructWithExplicitLayout = IsStructWithExplicitLayout(typeNode as Struct);
if (isStructWithExplicitLayout)
{
this.HandleError(new Warning(1044, String.Format("Struct '{0}' has explicit layout and an invariant. Invariant recursion guards will not be emitted and evaluation of invariants may occur too eagerly.", typeNode.FullName), new SourceContext()));
}
else
{
#region Find or create re-entrancy flag to the class
if (baseReentrancyFlag != null)
{
// grab base reEntrancyFlag
reEntrancyFlag = baseReentrancyFlag;
}
else
{
FieldFlags reentrancyFlagProtection;
if (typeNode.IsSealed)
{
reentrancyFlagProtection = FieldFlags.Private | FieldFlags.CompilerControlled;
}
else if (this.InheritInvariantsAcrossAssemblies)
{
reentrancyFlagProtection = FieldFlags.Family | FieldFlags.CompilerControlled;
}
else
{
reentrancyFlagProtection = FieldFlags.FamANDAssem | FieldFlags.CompilerControlled;
}
reEntrancyFlag = new Field(typeNode, null, reentrancyFlagProtection, Identifier.For("$evaluatingInvariant$"), SystemTypes.Boolean, null);
RewriteHelper.TryAddCompilerGeneratedAttribute(reEntrancyFlag);
RewriteHelper.TryAddDebuggerBrowsableNeverAttribute(reEntrancyFlag);
typeNode.Members.Add(reEntrancyFlag);
}
#endregion Add re-entrancy flag to the class
}
Block newBody = new Block(new StatementList(3));
// newBody ::=
// if (this.$evaluatingInvariant$){
// return (true); // don't really return true since this is a void method, but it means the invariant is assumed to hold
// this.$evaluatingInvariant$ := true;
// try{
// <evaluate invariants and call base invariant method>
// } finally {
// this.$evaluatingInvariant$ := false;
// }
Method invariantMethod =
new Method(
typeNode,
new AttributeList(),
Identifier.For("$InvariantMethod$"),
null,
SystemTypes.Void,
newBody);
RewriteHelper.TryAddCompilerGeneratedAttribute(invariantMethod);
invariantMethod.CallingConvention = CallingConventionFlags.HasThis;
if (this.InheritInvariantsAcrossAssemblies)
invariantMethod.Flags = MethodFlags.Family | MethodFlags.Virtual;
else
invariantMethod.Flags = MethodFlags.FamANDAssem | MethodFlags.Virtual;
invariantMethod.Attributes.Add(new AttributeNode(new MemberBinding(null, this.runtimeContracts.ContractNodes.InvariantMethodAttribute.GetConstructor()), null));
#region call base class invariant
if (baseInvariantMethod != null)
{
newBody.Statements.Add(
new ExpressionStatement(
new MethodCall(
new MemberBinding(invariantMethod.ThisParameter, baseInvariantMethod), null, NodeType.Call, SystemTypes.Void)));
}
#endregion
#region Add re-entrancy test to the method
Block invariantExit = new Block();
if (reEntrancyFlag != null)
{
Block reEntrancyTest = new Block(new StatementList());
reEntrancyTest.Statements.Add(
new Branch(new MemberBinding(invariantMethod.ThisParameter, reEntrancyFlag), invariantExit));
reEntrancyTest.Statements.Add(
new AssignmentStatement(new MemberBinding(invariantMethod.ThisParameter, reEntrancyFlag), Literal.True)
);
newBody.Statements.Add(reEntrancyTest);
}
#endregion Add re-entrancy test to the method
Block invariantChecks = new Block(new StatementList());
if (userWrittenInvariants != null)
{
#region Filter out invariants that aren't runtime checkable
var filteredInvariants = new InvariantList();
foreach (var i in userWrittenInvariants) {
if (!EmitInvariant(i, this.skipQuantifiers)) continue;
filteredInvariants.Add(i);
}
#endregion Filter out invariants that aren't runtime checkable
#region Duplicate the invariants
// need to duplicate the invariants so they aren't shared
Duplicator d = new Duplicator(typeNode.DeclaringModule, typeNode);
InvariantList duplicatedInvariants = d.VisitInvariantList(filteredInvariants);
// F: seems to have the invariant duplictedInvariants != null
Contract.Assume(duplicatedInvariants != null);
#endregion Duplicate the invariants
#region Rewrite the body of the invariant method
// then we need to replace calls to Contract.Invariant with calls to Contract.RewriterInvariant
// in the body of the invariant method
RewriteInvariant rc = new RewriteInvariant(this.runtimeContracts);
rc.VisitInvariantList(duplicatedInvariants);
#endregion Rewrite the body of the invariant method
for (int i = 0, n = duplicatedInvariants.Count; i < n; i++)
{
Expression e = duplicatedInvariants[i].Condition;
var blockExpr = e as BlockExpression;
if (blockExpr != null)
{
invariantChecks.Statements.Add(blockExpr.Block);
}
else
{
invariantChecks.Statements.Add(new ExpressionStatement(e));
}
}
}
Block finallyB = new Block(new StatementList(1));
if (reEntrancyFlag != null)
{
finallyB.Statements.Add(
new AssignmentStatement(new MemberBinding(invariantMethod.ThisParameter, reEntrancyFlag), Literal.False)
);
}
this.cleanUpCodeCoverage.VisitBlock(invariantChecks);
Block b = RewriteHelper.CreateTryFinallyBlock(invariantMethod, invariantChecks, finallyB);
newBody.Statements.Add(b);
newBody.Statements.Add(invariantExit);
newBody.Statements.Add(new Return());
// set the field "this.InvariantMethod" to this one so it is used in calls within each method
// but don't add it yet to the class so it doesn't get visited!
this.InvariantMethod = invariantMethod;
this.ReentrancyFlag = reEntrancyFlag;
}
}
base.VisitTypeNode(typeNode);
// Now add invariant method to the class
if (this.InvariantMethod != null)
{
typeNode.Members.Add(this.InvariantMethod);
}
return;
}
finally
{
this.InvariantMethod = savedInvariantMethod;
this.ReentrancyFlag = savedReentrancyFlag;
this.currentState = savedState;
this.contractEmitFlags = savedEmitFlags;
}
}
private Class MakeContractException() {
Class contractExceptionType;
#region If we're rewriting an assembly for v4 or above and it *isn't* Silverlight (so serialization support is needed), then use new embedded dll as the type
if (4 <= TargetPlatform.MajorVersion) {
var iSafeSerializationData = SystemTypes.SystemAssembly.GetType(Identifier.For("System.Runtime.Serialization"), Identifier.For("ISafeSerializationData")) as Interface;
if (iSafeSerializationData != null) {
// Just much easier to write the C# and have the compiler generate everything than to try and create it all manually
System.Reflection.Assembly embeddedAssembly;
Stream embeddedAssemblyStream;
embeddedAssembly = System.Reflection.Assembly.GetExecutingAssembly();
embeddedAssemblyStream = embeddedAssembly.GetManifestResourceStream("Microsoft.Contracts.Foxtrot.InternalException.dll");
byte[] data = new byte[0];
using (var br = new BinaryReader(embeddedAssemblyStream)) {
var len = embeddedAssemblyStream.Length;
if (len < Int32.MaxValue)
data = br.ReadBytes((int)len);
AssemblyNode assemblyNode = AssemblyNode.GetAssembly(data, TargetPlatform.StaticAssemblyCache, true, false, true);
contractExceptionType = assemblyNode.GetType(Identifier.For(""), Identifier.For("ContractException")) as Class;
}
if (contractExceptionType == null)
throw new RewriteException("Tried to create the ContractException type from the embedded dll, but failed");
var d = new Duplicator(this.targetAssembly, this.RuntimeContractType);
d.FindTypesToBeDuplicated(new TypeNodeList(contractExceptionType));
var ct = d.Visit(contractExceptionType);
contractExceptionType = (Class)ct;
contractExceptionType.Flags |= TypeFlags.NestedPrivate;
this.RuntimeContractType.Members.Add(contractExceptionType);
return contractExceptionType;
}
}
#endregion
contractExceptionType = new Class(this.targetAssembly, this.RuntimeContractType, new AttributeList(), TypeFlags.Class | TypeFlags.NestedPrivate | TypeFlags.Serializable, null, Identifier.For("ContractException"), SystemTypes.Exception, null, null);
RewriteHelper.TryAddCompilerGeneratedAttribute(contractExceptionType);
var kindField = new Field(contractExceptionType, null, FieldFlags.Private, Identifier.For("_Kind"), contractNodes.ContractFailureKind, null);
var userField = new Field(contractExceptionType, null, FieldFlags.Private, Identifier.For("_UserMessage"), SystemTypes.String, null);
var condField = new Field(contractExceptionType, null, FieldFlags.Private, Identifier.For("_Condition"), SystemTypes.String, null);
contractExceptionType.Members.Add(kindField);
contractExceptionType.Members.Add(userField);
contractExceptionType.Members.Add(condField);
#region Constructor for setting the fields
var parameters = new ParameterList();
var kindParam = new Parameter(Identifier.For("kind"), this.contractNodes.ContractFailureKind);
var failureParam = new Parameter(Identifier.For("failure"), SystemTypes.String);
var usermsgParam = new Parameter(Identifier.For("usermsg"), SystemTypes.String);
var conditionParam = new Parameter(Identifier.For("condition"), SystemTypes.String);
var innerParam = new Parameter(Identifier.For("inner"), SystemTypes.Exception);
parameters.Add(kindParam);
parameters.Add(failureParam);
parameters.Add(usermsgParam);
parameters.Add(conditionParam);
parameters.Add(innerParam);
var body = new Block(new StatementList());
var ctor = new InstanceInitializer(contractExceptionType, null, parameters, body);
ctor.Flags |= MethodFlags.Public | MethodFlags.HideBySig;
ctor.CallingConvention = CallingConventionFlags.HasThis;
body.Statements.Add(new ExpressionStatement(new MethodCall(new MemberBinding(ctor.ThisParameter, contractExceptionType.BaseClass.GetConstructor(SystemTypes.String, SystemTypes.Exception)), new ExpressionList(failureParam, innerParam))));
body.Statements.Add(new AssignmentStatement(new MemberBinding(ctor.ThisParameter, kindField), kindParam));
body.Statements.Add(new AssignmentStatement(new MemberBinding(ctor.ThisParameter, userField), usermsgParam));
body.Statements.Add(new AssignmentStatement(new MemberBinding(ctor.ThisParameter, condField), conditionParam));
body.Statements.Add(new Return());
contractExceptionType.Members.Add(ctor);
#endregion
if (SystemTypes.SerializationInfo != null && SystemTypes.SerializationInfo.BaseClass != null) {
// Silverlight (e.g.) is a platform that doesn't support serialization. So check to make sure the type really exists.
//
var baseCtor = SystemTypes.Exception.GetConstructor(SystemTypes.SerializationInfo, SystemTypes.StreamingContext);
if (baseCtor != null) {
#region Deserialization Constructor
parameters = new ParameterList();
var info = new Parameter(Identifier.For("info"), SystemTypes.SerializationInfo);
var context = new Parameter(Identifier.For("context"), SystemTypes.StreamingContext);
parameters.Add(info);
parameters.Add(context);
body = new Block(new StatementList());
ctor = new InstanceInitializer(contractExceptionType, null, parameters, body);
ctor.Flags |= MethodFlags.Private | MethodFlags.HideBySig;
ctor.CallingConvention = CallingConventionFlags.HasThis;
// : base(info, context)
body.Statements.Add(new ExpressionStatement(new MethodCall(new MemberBinding(ctor.ThisParameter, baseCtor), new ExpressionList(info, context))));
// _Kind = (ContractFailureKind)info.GetInt32("Kind");
var getInt32 = SystemTypes.SerializationInfo.GetMethod(Identifier.For("GetInt32"), SystemTypes.String);
body.Statements.Add(new AssignmentStatement(
new MemberBinding(new This(), kindField),
new MethodCall(new MemberBinding(info, getInt32), new ExpressionList(new Literal("Kind", SystemTypes.String)))
));
// _UserMessage = info.GetString("UserMessage");
var getString = SystemTypes.SerializationInfo.GetMethod(Identifier.For("GetString"), SystemTypes.String);
body.Statements.Add(new AssignmentStatement(
new MemberBinding(new This(), userField),
new MethodCall(new MemberBinding(info, getString), new ExpressionList(new Literal("UserMessage", SystemTypes.String)))
));
// _Condition = info.GetString("Condition");
body.Statements.Add(new AssignmentStatement(
new MemberBinding(new This(), condField),
new MethodCall(new MemberBinding(info, getString), new ExpressionList(new Literal("Condition", SystemTypes.String)))
));
body.Statements.Add(new Return());
contractExceptionType.Members.Add(ctor);
#endregion
#region GetObjectData
var securityCriticalCtor = SystemTypes.SecurityCriticalAttribute.GetConstructor();
var securityCriticalAttribute = new AttributeNode(new MemberBinding(null, securityCriticalCtor), null, System.AttributeTargets.Method);
var attrs = new AttributeList(securityCriticalAttribute);
parameters = new ParameterList();
info = new Parameter(Identifier.For("info"), SystemTypes.SerializationInfo);
context = new Parameter(Identifier.For("context"), SystemTypes.StreamingContext);
parameters.Add(info);
parameters.Add(context);
body = new Block(new StatementList());
var getObjectDataName = Identifier.For("GetObjectData");
var getObjectData = new Method(contractExceptionType, attrs, getObjectDataName, parameters, SystemTypes.Void, body);
getObjectData.CallingConvention = CallingConventionFlags.HasThis;
// public override
getObjectData.Flags = MethodFlags.Public | MethodFlags.Virtual;
// base.GetObjectData(info, context);
var baseGetObjectData = SystemTypes.Exception.GetMethod(getObjectDataName, SystemTypes.SerializationInfo, SystemTypes.StreamingContext);
body.Statements.Add(new ExpressionStatement(
new MethodCall(new MemberBinding(new This(), baseGetObjectData), new ExpressionList(info, context), NodeType.Call, SystemTypes.Void)
));
// info.AddValue("Kind", _Kind);
var addValueObject = SystemTypes.SerializationInfo.GetMethod(Identifier.For("AddValue"), SystemTypes.String, SystemTypes.Object);
body.Statements.Add(new ExpressionStatement(
new MethodCall(new MemberBinding(info, addValueObject), new ExpressionList(new Literal("Kind", SystemTypes.String), new BinaryExpression(new MemberBinding(new This(), kindField), new Literal(contractNodes.ContractFailureKind), NodeType.Box)), NodeType.Call, SystemTypes.Void)
));
// info.AddValue("UserMessage", _UserMessage);
body.Statements.Add(new ExpressionStatement(
new MethodCall(new MemberBinding(info, addValueObject), new ExpressionList(new Literal("UserMessage", SystemTypes.String), new MemberBinding(new This(), userField)), NodeType.Call, SystemTypes.Void)
));
// info.AddValue("Condition", _Condition);
body.Statements.Add(new ExpressionStatement(
new MethodCall(new MemberBinding(info, addValueObject), new ExpressionList(new Literal("Condition", SystemTypes.String), new MemberBinding(new This(), condField)), NodeType.Call, SystemTypes.Void)
));
body.Statements.Add(new Return());
contractExceptionType.Members.Add(getObjectData);
#endregion
}
}
this.RuntimeContractType.Members.Add(contractExceptionType);
return contractExceptionType;
}
public static bool FieldIsAdditive(Field field) {
if (field == null) return false;
AttributeNode attr = field.GetAttribute(SystemTypes.AdditiveAttribute);
if (attr == null) return false;
ExpressionList exprs = attr.Expressions;
if (exprs == null || exprs.Count != 1) return true;
Literal lit = exprs[0] as Literal;
if (lit != null && (lit.Value is bool)) return (bool)lit.Value;
else return false;
}
public override Field VisitField(Field field)
{
if (field == null) return null;
if (!this.IncludeModels && HelperMethods.HasAttribute(field.Attributes, ContractNodes.ModelAttributeName))
return null;
return base.VisitField(field);
}
private static Field GetInstanceField(TypeNode originalReturnType, Field possiblyGenericField, TypeNode instanceDeclaringType)
{
Contract.Requires(instanceDeclaringType != null);
if (instanceDeclaringType.Template == null) return possiblyGenericField;
var declaringTemplate = instanceDeclaringType;
while (declaringTemplate.Template != null) { declaringTemplate = declaringTemplate.Template; }
Contract.Assume(declaringTemplate == possiblyGenericField.DeclaringType);
return Rewriter.GetFieldInstanceReference(possiblyGenericField, instanceDeclaringType);
#if false
Field f = instanceDeclaringType.GetField(possiblyGenericField.Name);
if (f != null)
{
// already instantiated
return f;
}
// pseudo instance
Field instance = new Field(instanceDeclaringType, possiblyGenericField.Attributes, possiblyGenericField.Flags, possiblyGenericField.Name, originalReturnType, null);
instanceDeclaringType.Members.Add(instance);
return instance;
#endif
}
public override void VisitMemberBinding(MemberBinding memberBinding)
{
Field f = memberBinding.BoundMember as Field;
if (f != null)
{
this.Found = f;
return;
}
base.VisitMemberBinding(memberBinding);
}
private static void AddEnumValue(EnumNode enumType, string name, object value)
{
var enumValue = new Field(enumType, null, FieldFlags.Assembly | FieldFlags.HasDefault | FieldFlags.Literal | FieldFlags.Static, Identifier.For(name), enumType, new Literal(value, SystemTypes.Int32));
enumType.Members.Add(enumValue);
}
internal static void TryAddCompilerGeneratedAttribute(Field field)
{
Contract.Requires(field != null);
TryAddCompilerGeneratedAttribute(field, System.AttributeTargets.Field);
}
internal static Field GetFieldInstanceReference(Field fieldOfGenericType, TypeNode instantiatedParentType) {
return (Field)GetMemberInstanceReference(fieldOfGenericType, instantiatedParentType);
}
/// <summary>
/// Write out a field name
/// </summary>
/// <param name="field">The field for which to write out the name</param>
/// <param name="sb">The string builder to which the name is written</param>
private static void WriteField(Field field, StringBuilder sb)
{
WriteType(field.DeclaringType, sb);
sb.Append('.');
sb.Append(field.Name.Name);
}
public override Expression VisitOldExpression(OldExpression oldExpression) {
if (this.topLevelClosureClass != null) {
#region In Closure ==> Create a field
// Since we're within a closure, we can't create a local to hold the value of the old expression
// but instead have to create a field for it. That field can be a member of the top-level
// closure class since nothing mentioned in the old expression (except possibly for the
// bound variables of enclosing quantifications) should be anything captured from
// an inner anonymous delegate.
// BUT, first we have to know if the old expression depends on any of the bound
// variables of the closures in which it is located. If not, then we can implement
// it as a scalar and just generate the assignment "closure_class.field := e" for
// "Old(e)" to take a snapshot of e's value in the prestate. If it does depend on
// any of the bound variables, then we need to generate a set of for-loops that
// compute the indices and values of e for each tuple of indices so it can be retrieved
// (given the indices) in the post-state.
CollectBoundVariables cbv = new CollectBoundVariables(this.stackOfBoundVariables);
cbv.VisitExpression(oldExpression.expression);
SubstituteClosureClassWithinOldExpressions subst =
new SubstituteClosureClassWithinOldExpressions(this.closureLocals);
Expression e = subst.VisitExpression(oldExpression.expression);
if (cbv.FoundVariables.Count == 0) {
#region Use a scalar for the old variable
Local closureLocal;
if (!this.closureLocals.TryGetValue(this.topLevelClosureClass, out closureLocal))
{
Contract.Assume(false, "can't find closure local!");
}
#region Define a scalar
var clTemplate = HelperMethods.Unspecialize(this.topLevelClosureClass);
Field f = new Field(clTemplate,
null,
FieldFlags.CompilerControlled | FieldFlags.Public,
Identifier.For("_old" + oldExpression.expression.UniqueKey.ToString()), // unique name for this old expr.
oldExpression.Type,
null);
clTemplate.Members.Add(f);
// now produce properly instantiated field
f = (Field)Rewriter.GetMemberInstanceReference(f, this.topLevelClosureClass);
#endregion
#region Generate code to store value in prestate
this.prestateValuesOfOldExpressions.Statements.Add(new AssignmentStatement(new MemberBinding(closureLocal, f), e));
#endregion
#region Return expression to be used in poststate
// Return an expression that will evaluate in the poststate to the value of the old
// expression in the prestate. This will be this.up.f where "up" is the field C#
// generated to point to the instance of the top-level closure class.
if (this.PointerToTopLevelClosureClass == null) {
// then the old expression occurs in the top-level closure class. Just return "this.f"
// where "this" refers to the top-level closure class.
return new MemberBinding(new This(this.currentClosureClass), f);
} else {
return new MemberBinding(
new MemberBinding(new This(this.currentClosureClass), this.PointerToTopLevelClosureClass),
f);
}
#endregion
#endregion
} else {
// the Old expression *does* depend upon at least one of the bound variable
// in a ForAll or Exists expression
#region Use an indexed variable for the old variable
TypeNode oldVariableTypeDomain;
#region Decide if domain is one-dimensional or not
bool oneDimensional = cbv.FoundVariables.Count == 1 && cbv.FoundVariables[0].Type.IsValueType;
if (oneDimensional) {
// a one-dimensional old-expression can use the index variable directly
oldVariableTypeDomain = cbv.FoundVariables[0].Type;
} else {
oldVariableTypeDomain = SystemTypes.GenericList.GetTemplateInstance(this.module, SystemTypes.Int32);
}
#endregion
TypeNode oldVariableTypeRange = oldExpression.Type;
TypeNode oldVariableType = SystemTypes.GenericDictionary.GetTemplateInstance(this.module, oldVariableTypeDomain, oldVariableTypeRange);
Local closureLocal;
if (!this.closureLocals.TryGetValue(this.topLevelClosureClass, out closureLocal))
{
Contract.Assume(false, "can't find closure local");
}
#region Define an indexed variable
var clTemplate = HelperMethods.Unspecialize(this.topLevelClosureClass);
Field f = new Field(clTemplate,
null,
FieldFlags.CompilerControlled | FieldFlags.Assembly, // can't be private or protected because it needs to be accessed from inner (closure) classes that don't inherit from the class this field is added to.
Identifier.For("_old" + oldExpression.expression.UniqueKey.ToString()), // unique name for this old expr.
oldVariableType,
null);
clTemplate.Members.Add(f);
// instantiate f
f = (Field)Rewriter.GetMemberInstanceReference(f, closureLocal.Type);
#endregion
#region Generate code to initialize the indexed variable
Statement init = new AssignmentStatement(
new MemberBinding(closureLocal, f),
new Construct(new MemberBinding(null, oldVariableType.GetConstructor()), null));
this.prestateValuesOfOldExpressions.Statements.Add(init);
#endregion
#region Generate code to store values in prestate
#region Create assignment: this.closure.f[i,j,k,...] = e;
Method setItem = oldVariableType.GetMethod(Identifier.For("set_Item"), oldVariableTypeDomain, oldVariableTypeRange);
Expression index;
if (oneDimensional) {
index = cbv.FoundVariables[0];
} else {
//InstanceInitializer ctor =
// ContractNodes.TupleClass.GetConstructor(SystemTypes.Int32.GetArrayType(1));
//Expression index = new Construct(new MemberBinding(null,ctor),new ExpressionList(
index = Literal.Null;
}
MethodCall mc = new MethodCall(new MemberBinding(new MemberBinding(closureLocal, f), setItem),
new ExpressionList(index, e));
Statement stat = new ExpressionStatement(mc);
#endregion
List<Local> locals = new List<Local>(this.stackOfBoundVariables.Count);
TrivialHashtable paramMap = new TrivialHashtable();
#region Generate a local for each bound variable to use in for-loop
foreach (Variable v in this.stackOfBoundVariables) {
Local l = new Local(Identifier.Empty, v.Type);
paramMap[v.UniqueKey] = l;
locals.Add(l);
}
#endregion
#region Substitute locals for bound variables in old expression *AND* in inner loop bounds
SubstituteParameters sps = new SubstituteParameters(paramMap, this.stackOfBoundVariables);
sps.Visit(stat);
#endregion
#region Create nested for-loops around assignment
// keep track of when the first variable is used (from innermost to outermost)
// as soon as the first one is needed because the old expression depends on it,
// then keep all enclosing loops. It would be possible to keep only those where
// the necessary loops have loop bounds that depend on an enclosing loop, but I
// haven't calculated that, so just keep them all. For instance, if the old expression
// depends on j and the loops are "for i,0,n" and inside that "for j,0,i", then need
// both loops. If the inner loop bounds were 0 and n, then wouldn't need the outer
// loop.
bool usedAVariable = false;
for (int i = this.stackOfBoundVariables.Count - 1; 0 <= i; i--) {
if (!usedAVariable
&& !cbv.FoundVariables.Contains(this.stackOfBoundVariables[i])) continue;
usedAVariable = true;
Expression lowerBound = new Duplicator(this.module, this.currentClosureClass).VisitExpression(
this.stackOfMethods[i].Operands[0]);
lowerBound = subst.VisitExpression(lowerBound);
lowerBound = sps.VisitExpression(lowerBound);
Expression upperBound = new Duplicator(this.module, this.currentClosureClass).VisitExpression(
this.stackOfMethods[i].Operands[1]);
upperBound = subst.VisitExpression(upperBound);
upperBound = sps.VisitExpression(upperBound);
stat = RewriteHelper.GenerateForLoop(locals[i], lowerBound, upperBound, stat);
}
#endregion
this.prestateValuesOfOldExpressions.Statements.Add(stat);
#endregion
#region Return expression to be used in poststate
Method getItem = oldVariableType.GetMethod(Identifier.For("get_Item"), oldVariableTypeDomain);
if (oneDimensional) {
index = cbv.FoundReferences[0];
} else {
//InstanceInitializer ctor =
// ContractNodes.TupleClass.GetConstructor(SystemTypes.Int32.GetArrayType(1));
//Expression index = new Construct(new MemberBinding(null,ctor),new ExpressionList(
index = Literal.Null;
}
// Return an expression that will evaluate in the poststate to the value of the old
// expression in the prestate. This will be this.up.f[i,j,k,...] where "up" is the field C#
// generated to point to the instance of the top-level closure class.
MemberBinding thisDotF;
if (this.PointerToTopLevelClosureClass == null) {
// then the old expression occurs in the top-level closure class. Just return "this.f"
// where "this" refers to the top-level closure class.
Contract.Assume(f != null);
thisDotF = new MemberBinding(new This(clTemplate), HelperMethods.Unspecialize(f));
} else {
thisDotF = new MemberBinding(
new MemberBinding(new This(clTemplate), this.PointerToTopLevelClosureClass),
f);
}
return new MethodCall(new MemberBinding(thisDotF, getItem), new ExpressionList(index));
#endregion
#endregion
}
#endregion
} else {
#region Not in closure ==> Create a local variable
Local l = GetLocalForOldExpression(oldExpression);
#region Make sure local can be seen in the debugger (for the entire method, unfortunately)
if (currentMethod.LocalList == null) {
currentMethod.LocalList = new LocalList();
}
currentMethod.LocalList.Add(l);
currentMethod.Body.HasLocals = true;
#endregion
this.prestateValuesOfOldExpressions.Statements.Add(
new AssignmentStatement(l, oldExpression.expression));
// Return an expression that will evaluate in the poststate to the value of the old
// expression in the prestate. When we're not in a closure, this is just the local
// itself.
return l;
#endregion
}
}
public override Field VisitField(Field field)
{
if (field == null) return null;
WriteStart(GetFieldQualifiers(field));
this.VisitTypeReference(field.Type);
Write(" {0}", field.Name.Name);
if (field.Initializer != null)
{
Write(" = ");
field.Initializer = this.VisitExpression(field.Initializer);
}
WriteFinish(";");
return field;
}
/// <summary>
/// If there is an anonymous delegate within a postcondition, then there
/// will be a call to a delegate constructor.
/// That call looks like "d..ctor(o,m)" where d is the type of the delegate.
/// There are two cases depending on whether the anonymous delegate captured
/// anything. In both cases, m is the method implementing the anonymous delegate.
///
/// (1) It does capture something. Then o is the instance of the closure class
/// implementing the delegate, and m is an instance method in the closure
/// class.
/// (2) It does *not* capture anything. Then o is the literal for null and
/// m is a static method that was added directly to the class.
///
/// This method will cause m to be visited to collect any old expressions
/// that occur in it. But those old expressions are not turned into locals,
/// but fields. The fields are created as either (1) members of the closure class,
/// or (2) members of the class in which the method containing the contract
/// containing the Old expression is defined.
/// The fields are initialized when (1) the closure class instance is created,
/// or (2) ... ??? (when!?)
/// So set up enough state so that when those old expressions are visited, the
/// correct ASTs can be built.
/// </summary>
/// <param name="cons">The AST representing the call to the constructor
/// of the delegate type.</param>
/// <returns>Whatever the base visitor returns</returns>
public override Expression VisitConstruct(Construct cons) {
if (cons.Type is DelegateNode) {
UnaryExpression ue = cons.Operands[1] as UnaryExpression;
if (ue == null) goto JustVisit;
MemberBinding mb = ue.Operand as MemberBinding;
if (mb == null) goto JustVisit;
Method m = mb.BoundMember as Method;
Contract.Assume(m != null);
if (m.IsStatic) {
// then there is no closure class, m is just a static method the compiler
// added to the class itself
goto JustVisit;
}
if (HelperMethods.IsCompilerGenerated(m)) {
Local l = cons.Operands[0] as Local;
if (l == null) goto JustVisit; // but then what is it??
TypeNode savedClosureClass = this.currentClosureClass;
this.currentClosureClass = l.Type;
if (savedClosureClass == null) {
// then this is the top-level closure class
// have to treat it special: it doesn't contain a field that points
// to the top-level closure class. The field introduced to hold the value of the
// old expression will be declared in this class.
this.topLevelClosureClass = this.currentClosureClass;
} else {
// Find the field in this.closureClass that the C# compiler generated
// to point to the top-level closure
foreach (Member mem in this.currentClosureClass.Members) {
Field f = mem as Field;
if (f == null) continue;
if (f.Type == this.topLevelClosureClass) {
this.PointerToTopLevelClosureClass = f;
break;
}
}
}
this.VisitBlock(m.Body);
if (savedClosureClass == null) {
this.topLevelClosureClass = null;
}
this.currentClosureClass = savedClosureClass;
this.PointerToTopLevelClosureClass = null;
}
}
JustVisit:
return base.VisitConstruct(cons);
}
private void CheckField(Field field)
{
Contract.Requires(field != null);
string s = HelperMethods.GetStringFromAttribute(field, ContractNodes.SpecPublicAttributeName);
if (s != null)
{
// okay if it is null, then it just doesn't have a named substitute to use in documentation, etc.
// make sure it is the name of a (public) field or (public) property, but it might be inherited
// Search class hierarchy for a field or a property
TypeNode t = field.DeclaringType;
bool error = true;
while (t != null && error)
{
Contract.Assert(t != null);
MemberList mems = t.GetMembersNamed(Identifier.For(s));
for (int i = 0, n = /*mems == null ? 0 : */ mems.Count; /*error && */i < n; i++)
{
Member mem = mems[i];
Field f = mem as Field;
if (f != null)
{
if (!f.IsPublic) continue;
//if (f.Type != field.Type) continue; // REVIEW: When it becomes possible, allow widening
error = false;
break;
}
Property p = mem as Property;
if (p != null)
{
Method getter = p.Getter;
if (getter == null) continue; // found by Clousot.
if (!getter.IsPublic) continue;
//if (getter.ReturnType != field.Type) continue; // REVIEW: When it becomes possible, allow widening
error = false;
break;
}
}
t = t.BaseType;
}
if (error)
{
this.HandleError(
new Error(1010, "Field '" +
field.FullName +
"' is marked [ContractPublicPropertyName(\"" + s +
"\")], but no public field/property named '" +
s + "' with type '" + field.Type + "' can be found",
field.SourceContext));
}
}
}
public virtual Field VisitField(Field field)
{
if (field == null) return null;
field.Attributes = this.VisitAttributeList(field.Attributes);
field.Type = this.VisitTypeReference(field.Type);
field.Initializer = this.VisitExpression(field.Initializer);
field.ImplementedInterfaces = this.VisitInterfaceReferenceList(field.ImplementedInterfaces);
return field;
}
