針對VLIW-based DSP指令排程方法的研究及其模擬環境的研製

Abstract

近年來，隨著個人攜帶式應用產品的普及，於影音資料與即時性資料的需求日益增加，因此，數位訊號處理器扮演的角色也日趨重要。如何能使資料即時且正確地展現在使用者面前成為了一個重要的課題，而指令的排程在整個過程中是一個很關鍵的步驟。在本論文中，我們以Push-up Scheduling Method為基礎，利用Retiming的觀念，在有限資源情況下，找到近乎最佳化的指令排程。接下來，我們在此排程方法中整合尋找schedule vector的程序，並放寬其中的限制，以建構我們的Relax Push-up Scheduling Method。我們的Relax Push-up Scheduling Method可以找到適用於該程式的schedule vector，使其執行時間為最佳化。在本文中，我們也研製了一套針對TI TMS320C62X系列DSP為對象的模擬與評估環境，將 Relax Push-up Scheduling Method在此環境上進行數項實驗，並與Push-up Scheduling Method及實際晶片上的效能作比較，更進一步驗證其優越的執行效能及的確能夠找出適當的schedule vector。我們會在接下來的本文中介紹Relax Push-up Scheduling Method演算法的詳細內容。

Digital signal processing on images and real-time data are more and more important by the popularization of portable devices recently. How to process data correctly in real-time is one of the most interesting topics to be investigated. The instruction scheduling is an important step through the whole process. In this thesis, we propose an effective algorithm, named Relax Push-up Scheduling Method (RPUSM), using the concept of retiming to find the near optimal solution under resource constraints. Our algorithm is based on Push-up Scheduling Method (PUSM) by relaxing its constraints and incorporating the procedure of finding suitable schedule vector. Our Relax Push-up Scheduling Method (RPUSM) can find the suitable schedule vector to obtain better execution time. For evaluating our algorithm, we also implement a simulation environment to verify it. According to our evaluations, our algorithms perform a well performance and find the more suitable schedule vector indeed. The detail descriptions of our algorithms will be given in the contents.