コード例 #1
0
        public override void Evaluate(ComputationContext ctx)
        {
            if (this.Evaluation == null)
            {
                FunctionDefinition func = this.EnclosingScope <FunctionDefinition>();
                if (func == null)
                {
                    ctx.ErrorManager.AddError(ErrorCode.ReturnOutsideFunction, this);
                }
                else
                {
                    if (func.IsResultTypeNameInfered)
                    {
                        if (this.Expr == null)
                        {
                            func.AddResultTypeCandidate(ctx.Env.UnitType.InstanceOf);
                        }
                        else
                        {
                            func.AddResultTypeCandidate(this.Expr.Evaluation.Components);
                        }
                    }
                    else
                    {
                        IEntityInstance func_result = func.ResultParameter.TypeName.Evaluation.Components;

                        if (this.Expr == null)
                        {
                            if (!ctx.Env.IsUnitType(func_result))
                            {
                                ctx.ErrorManager.AddError(ErrorCode.EmptyReturn, this);
                            }
                        }
                        else
                        {
                            this.DataTransfer(ctx, ref this.expr, func_result);
                        }
                    }
                }

                // https://stackoverflow.com/questions/7563981/why-isnt-g-tail-call-optimizing-while-gcc-is
                // http://www.drdobbs.com/tackling-c-tail-calls/184401756
                if (this.Expr is FunctionCall call && call.IsRecall() &&
                    !func.Parameters.Any(it => ctx.Env.IsReferenceOfType(it.TypeName.Evaluation.Components)))
                {
                    this.TailCallOptimization = call;
                }

                this.Evaluation = ctx.Env.UnitEvaluation;
            }
        }