/// <summary>
/// There are 2 cases:
/// 1) Task has no return value. In this case, we emit
/// void CheckMethod(Task t) {
/// var ae = t.Exception as AggregateException;
/// if (ae != null) { ae.Handle(this.CheckException); throw ae; }
/// }
/// bool CheckException(Exception e) {
/// .. check exceptional post
/// }
/// 2) Task(T) returns a T value
/// T CheckMethod(Task t) {
/// try {
/// var r = t.Result;
/// .. check ensures on r ..
/// return r;
/// }
/// catch (AggregateException ae) {
/// ae.Handle(this.CheckException);
/// throw;
/// }
/// }
/// bool CheckException(Exception e) {
/// .. check exceptional post
/// }
/// </summary>
public EmitAsyncClosure(Method from, Rewriter parent)
{
this.fromMethod = from;
this.parent = parent;
this.checkMethodId = Identifier.For("CheckPost");
this.checkExceptionMethodId = Identifier.For("CheckException");
this.declaringType = from.DeclaringType;
var closureName = HelperMethods.NextUnusedMemberName(declaringType, "<" + from.Name.Name + ">AsyncContractClosure");
this.closureClass = new Class(declaringType.DeclaringModule, declaringType, null, TypeFlags.NestedPrivate, null, Identifier.For(closureName), SystemTypes.Object, null, null);
declaringType.Members.Add(this.closureClass);
RewriteHelper.TryAddCompilerGeneratedAttribute(this.closureClass);
this.dup = new Duplicator(this.declaringType.DeclaringModule, this.declaringType);
var taskType = from.ReturnType;
var taskArgs = taskType.TemplateArguments == null ? 0 : taskType.TemplateArguments.Count;
this.AggregateExceptionType = new Cache<TypeNode>(() =>
HelperMethods.FindType(parent.assemblyBeingRewritten, StandardIds.System, Identifier.For("AggregateException")));
this.Func2Type = new Cache<TypeNode>(() =>
HelperMethods.FindType(SystemTypes.SystemAssembly, StandardIds.System, Identifier.For("Func`2")));
if (from.IsGeneric)
{
this.closureClass.TemplateParameters = new TypeNodeList();
var parentCount = this.declaringType.ConsolidatedTemplateParameters == null ? 0 : this.declaringType.ConsolidatedTemplateParameters.Count;
for (int i = 0; i < from.TemplateParameters.Count; i++)
{
var tp = HelperMethods.NewEqualTypeParameter(dup, (ITypeParameter)from.TemplateParameters[i], this.closureClass, parentCount + i);
this.closureClass.TemplateParameters.Add(tp);
}
this.closureClass.IsGeneric = true;
this.closureClass.EnsureMangledName();
this.forwarder = new Specializer(this.declaringType.DeclaringModule, from.TemplateParameters, this.closureClass.TemplateParameters);
this.forwarder.VisitTypeParameterList(this.closureClass.TemplateParameters);
taskType = this.forwarder.VisitTypeReference(taskType);
}
else
{
this.closureClassInstance = this.closureClass;
}
var taskTemplate = HelperMethods.Unspecialize(taskType);
var continueWithCandidates = taskTemplate.GetMembersNamed(Identifier.For("ContinueWith"));
Method continueWithMethod = null;
for (int i = 0; i < continueWithCandidates.Count; i++)
{
var cand = continueWithCandidates[i] as Method;
if (cand == null) continue;
if (taskArgs == 0)
{
if (cand.IsGeneric) continue;
if (cand.ParameterCount != 1) continue;
var p = cand.Parameters[0];
var ptype = p.Type;
var ptypeTemplate = ptype;
while (ptypeTemplate.Template != null)
{
ptypeTemplate = ptypeTemplate.Template;
}
if (ptypeTemplate.Name.Name != "Action`1") continue;
continueWithMethod = cand;
break;
}
else
{
if (!cand.IsGeneric) continue;
if (cand.TemplateParameters.Count != 1) continue;
if (cand.ParameterCount != 1) continue;
var p = cand.Parameters[0];
var ptype = p.Type;
var ptypeTemplate = ptype;
while (ptypeTemplate.Template != null)
{
ptypeTemplate = ptypeTemplate.Template;
}
if (ptypeTemplate.Name.Name != "Func`2") continue;
// now create instance, first of task
var taskInstance = taskTemplate.GetTemplateInstance(this.closureClass.DeclaringModule, taskType.TemplateArguments[0]);
var candMethod = taskInstance.GetMembersNamed(Identifier.For("ContinueWith"))[i] as Method;
continueWithMethod = candMethod.GetTemplateInstance(null, taskType.TemplateArguments[0]);
break;
}
}
if (continueWithMethod != null)
{
this.continuewithMethod = continueWithMethod;
EmitCheckMethod(taskType, taskArgs == 1);
var ctor = new InstanceInitializer(this.closureClass, null, null, null);
this.constructor = ctor;
ctor.CallingConvention = CallingConventionFlags.HasThis;
ctor.Flags |= MethodFlags.Public | MethodFlags.HideBySig;
ctor.Body = new Block(new StatementList(
new ExpressionStatement(new MethodCall(new MemberBinding(ctor.ThisParameter, SystemTypes.Object.GetConstructor()), new ExpressionList())),
new Return()
));
this.closureClass.Members.Add(ctor);
}
// now that we added the ctor and the check method, let's instantiate the closure class if necessary
if (this.closureClassInstance == null)
{
var consArgs = new TypeNodeList();
var args = new TypeNodeList();
var parentCount = this.closureClass.DeclaringType.ConsolidatedTemplateParameters == null ? 0 : this.closureClass.DeclaringType.ConsolidatedTemplateParameters.Count;
for (int i = 0; i < parentCount; i++)
{
consArgs.Add(this.closureClass.DeclaringType.ConsolidatedTemplateParameters[i]);
}
var methodCount = from.TemplateParameters == null ? 0: from.TemplateParameters.Count;
for (int i = 0; i < methodCount; i++)
{
consArgs.Add(from.TemplateParameters[i]);
args.Add(from.TemplateParameters[i]);
}
this.closureClassInstance = (Class)this.closureClass.GetConsolidatedTemplateInstance(this.parent.assemblyBeingRewritten, closureClass.DeclaringType, closureClass.DeclaringType, args, consArgs);
}
// create closure initializer for context method
this.ClosureLocal = new Local(this.ClosureClass);
this.ClosureInitializer = new Block(new StatementList());
this.ClosureInitializer.Statements.Add(new AssignmentStatement(this.ClosureLocal, new Construct(new MemberBinding(null, this.Ctor), new ExpressionList())));
}
public RewriteAssertAssumeAndCallSiteRequires(Dictionary<Method, bool> replacementMethods, RuntimeContractMethods runtimeContracts, RuntimeContractEmitFlags emitFlags, Rewriter parent,
Method containingMethod)
{
this.methodTable = replacementMethods;
this.runtimeContracts = runtimeContracts;
this.emitFlags = emitFlags;
this.parent = parent;
this.containingMethod = containingMethod;
}
public EmitAsyncClosure(Method from, Rewriter rewriter)
{
Contract.Requires(from != null);
Contract.Requires(from.DeclaringType != null);
Contract.Requires(rewriter != null);
if (TaskExtensionsTypeNode == null)
{
throw new InvalidOperationException(
"Can't generate async closure because System.Threading.Tasks.TaskExceptions class is unavailable.");
}
this.rewriter = rewriter;
this.declaringType = from.DeclaringType;
var closureName = HelperMethods.NextUnusedMemberName(declaringType, "<" + from.Name.Name + ">AsyncContractClosure");
this.closureClass = new Class(
declaringModule: declaringType.DeclaringModule,
declaringType: declaringType,
attributes: null,
flags: TypeFlags.NestedPrivate,
Namespace: null,
name: Identifier.For(closureName),
baseClass: SystemTypes.Object,
interfaces: null,
members: null);
declaringType.Members.Add(this.closureClass);
RewriteHelper.TryAddCompilerGeneratedAttribute(this.closureClass);
var taskType = from.ReturnType;
this.aggregateExceptionType = new Cache<TypeNode>(() =>
HelperMethods.FindType(rewriter.AssemblyBeingRewritten, StandardIds.System,
Identifier.For("AggregateException")));
this.func2Type = new Cache<TypeNode>(() =>
HelperMethods.FindType(SystemTypes.SystemAssembly, StandardIds.System, Identifier.For("Func`2")));
// Should distinguish between generic enclosing method and non-generic method in enclosing type.
// In both cases generated closure should be generic.
var enclosingTemplateParameters = GetGenericTypesFrom(from);
if (!enclosingTemplateParameters.IsNullOrEmpty())
{
this.closureClass.TemplateParameters = CreateTemplateParameters(closureClass, enclosingTemplateParameters, declaringType);
this.closureClass.IsGeneric = true;
this.closureClass.EnsureMangledName();
this.forwarder = new Specializer(
targetModule: this.declaringType.DeclaringModule,
pars: enclosingTemplateParameters,
args: this.closureClass.TemplateParameters);
this.forwarder.VisitTypeParameterList(this.closureClass.TemplateParameters);
taskType = this.forwarder.VisitTypeReference(taskType);
for (int i = 0; i < enclosingTemplateParameters.Count; i++)
{
this.genericTypeMapper.AddMapping(enclosingTemplateParameters[i], closureClass.TemplateParameters[i]);
}
}
else
{
this.closureClassInstance = this.closureClass;
}
this.checkMethodTaskType = taskType;
// Emiting CheckPost method declaration
EmitCheckPostMethodCore(checkMethodTaskType);
// Generate closure constructor.
// Constructor should be generated AFTER visiting type parameters in
// the previous block of code. Otherwise current class would not have
// appropriate number of generic arguments!
var ctor = CreateConstructor(closureClass);
closureClass.Members.Add(ctor);
// Now that we added the ctor and the check method, let's instantiate the closure class if necessary
if (this.closureClassInstance == null)
{
var consArgs = new TypeNodeList();
var args = new TypeNodeList();
var parentCount = this.closureClass.DeclaringType.ConsolidatedTemplateParameters == null
? 0
: this.closureClass.DeclaringType.ConsolidatedTemplateParameters.Count;
for (int i = 0; i < parentCount; i++)
{
consArgs.Add(this.closureClass.DeclaringType.ConsolidatedTemplateParameters[i]);
}
if (!enclosingTemplateParameters.IsNullOrEmpty())
{
for (int i = 0; i < enclosingTemplateParameters.Count; i++)
{
consArgs.Add(enclosingTemplateParameters[i]);
args.Add(enclosingTemplateParameters[i]);
}
}
this.closureClassInstance =
(Class)
this.closureClass.GetConsolidatedTemplateInstance(this.rewriter.AssemblyBeingRewritten,
closureClass.DeclaringType, closureClass.DeclaringType, args, consArgs);
}
// create closure initializer for context method
this.closureLocal = new Local(this.ClosureClass);
this.ClosureInitializer = new Block(new StatementList());
// Generate constructor call that initializes closure instance
this.ClosureInitializer.Statements.Add(
new AssignmentStatement(
this.closureLocal,
new Construct(new MemberBinding(null, this.Ctor), new ExpressionList())));
}