void CachedDelegateInitializationWithLocal(ILBlock block, ref int i)
        {
            // if (logicnot(ldloc(v))) {
            //     stloc(v, newobj(Action::.ctor, ldloc(displayClass), ldftn(method)))
            // } else {
            // }
            // ...(..., ldloc(v), ...)

            ILCondition c = block.Body[i] as ILCondition;

            if (c == null || c.Condition == null && c.TrueBlock == null || c.FalseBlock == null)
            {
                return;
            }
            if (!(c.TrueBlock.Body.Count == 1 && c.FalseBlock.Body.Count == 0))
            {
                return;
            }
            if (!c.Condition.Match(ILCode.LogicNot))
            {
                return;
            }
            ILExpression condition = c.Condition.Arguments.Single() as ILExpression;

            if (condition == null || condition.Code != ILCode.Ldloc)
            {
                return;
            }
            ILVariable   v     = (ILVariable)condition.Operand;
            ILExpression stloc = c.TrueBlock.Body[0] as ILExpression;

            if (!(stloc != null && stloc.Code == ILCode.Stloc && (ILVariable)stloc.Operand == v))
            {
                return;
            }
            ILExpression newObj = stloc.Arguments[0];

            if (!(newObj.Code == ILCode.Newobj && newObj.Arguments.Count == 2))
            {
                return;
            }
            if (newObj.Arguments[0].Code != ILCode.Ldloc)
            {
                return;
            }
            if (newObj.Arguments[1].Code != ILCode.Ldftn)
            {
                return;
            }
            MethodDefinition anonymousMethod = ((MethodReference)newObj.Arguments[1].Operand).ResolveWithinSameModule();             // method is defined in current assembly

            if (!AstServices.Transforms.DelegateConstruction.IsAnonymousMethod(context, anonymousMethod))
            {
                return;
            }

            ILNode followingNode     = block.Body.ElementAtOrDefault(i + 1);
            int    ldlocOperandCount =
                followingNode
                .EnumerateSelfAndChildrenRecursive()
                .OfType <ILExpression>()
                .Count(
                    e =>
                    e.Code == ILCode.Ldloc &&
                    (ILVariable)e.Operand == v);

            if (followingNode != null && ldlocOperandCount == 1)
            {
                ILInlining inlining = new ILInlining(method);
                if (!(inlining.numLdloc.GetOrDefault(v) == 2 && inlining.numStloc.GetOrDefault(v) == 2 && inlining.numLdloca.GetOrDefault(v) == 0))
                {
                    return;
                }

                // Find the store instruction that initializes the local to null:
                foreach (ILBlock storeBlock in method.EnumerateSelfAndChildrenRecursive().OfType <ILBlock>())
                {
                    for (int j = 0; j < storeBlock.Body.Count; j++)
                    {
                        ILVariable   storedVar;
                        ILExpression storedExpr;
                        if (storeBlock.Body[j].Match(ILCode.Stloc, out storedVar, out storedExpr) && storedVar == v && storedExpr.Match(ILCode.Ldnull))
                        {
                            // Remove the instruction
                            storeBlock.Body.RemoveAt(j);
                            if (storeBlock == block && j < i)
                            {
                                i--;
                            }
                            break;
                        }
                    }
                }

                block.Body[i] = stloc;                 // remove the 'if (v==null)'
                inlining      = new ILInlining(method);
                inlining.InlineIfPossible(block.Body, ref i);
            }
        }
        void CachedDelegateInitializationWithField(ILBlock block, ref int i)
        {
            // if (logicnot(ldsfld(field))) {
            //     stsfld(field, newobj(Action::.ctor, ldnull(), ldftn(method)))
            // } else {
            // }
            // ...(..., ldsfld(field), ...)

            ILCondition c = block.Body[i] as ILCondition;

            if (c == null || c.Condition == null && c.TrueBlock == null || c.FalseBlock == null)
            {
                return;
            }
            if (!(c.TrueBlock.Body.Count == 1 && c.FalseBlock.Body.Count == 0))
            {
                return;
            }
            if (!c.Condition.Match(ILCode.LogicNot))
            {
                return;
            }
            ILExpression condition = c.Condition.Arguments.Single() as ILExpression;

            if (condition == null || condition.Code != ILCode.Ldsfld)
            {
                return;
            }
            FieldDefinition field = ((FieldReference)condition.Operand).ResolveWithinSameModule();             // field is defined in current assembly

            if (field == null || !field.IsCompilerGeneratedOrIsInCompilerGeneratedClass())
            {
                return;
            }
            ILExpression stsfld = c.TrueBlock.Body[0] as ILExpression;

            if (!(stsfld != null && stsfld.Code == ILCode.Stsfld && ((FieldReference)stsfld.Operand).ResolveWithinSameModule() == field))
            {
                return;
            }
            ILExpression newObj = stsfld.Arguments[0];

            if (!(newObj.Code == ILCode.Newobj && newObj.Arguments.Count == 2))
            {
                return;
            }
            if (newObj.Arguments[0].Code != ILCode.Ldnull)
            {
                return;
            }
            if (newObj.Arguments[1].Code != ILCode.Ldftn)
            {
                return;
            }
            MethodDefinition anonymousMethod = ((MethodReference)newObj.Arguments[1].Operand).ResolveWithinSameModule();             // method is defined in current assembly

            if (!AstServices.Transforms.DelegateConstruction.IsAnonymousMethod(context, anonymousMethod))
            {
                return;
            }

            ILNode followingNode = block.Body.ElementAtOrDefault(i + 1);

            int ldfldResolvingWithinSameMethodCount =
                followingNode
                .EnumerateSelfAndChildrenRecursive()
                .OfType <ILExpression>()
                .Count(
                    e =>
                    e.Code == ILCode.Ldsfld &&
                    ((FieldReference)e.Operand).ResolveWithinSameModule() == field);

            if (followingNode != null && ldfldResolvingWithinSameMethodCount == 1)
            {
                foreach (ILExpression parent in followingNode.EnumerateSelfAndChildrenRecursive().OfType <ILExpression>())
                {
                    for (int j = 0; j < parent.Arguments.Count; j++)
                    {
                        if (parent.Arguments[j].Code == ILCode.Ldsfld && ((FieldReference)parent.Arguments[j].Operand).ResolveWithinSameModule() == field)
                        {
                            parent.Arguments[j] = newObj;
                            block.Body.RemoveAt(i);
                            i -= new ILInlining(method).InlineInto(block.Body, i, aggressive: false);
                            return;
                        }
                    }
                }
            }
        }