隨著多核心平台越來越廣泛，程式設計師大多採用多線程編程技巧來提高效能，然而多線程程式容易造成同步錯誤，例如資料競爭，不幸的已提出的軟體架構資料競爭偵測器的效能緩慢，而已提出硬體架構資料競爭偵測器的偵測並不精確。

在本論文中，我們提出兩種硬體架構資料競爭偵測機制用於多核心系統偵測同步問題，我們首先基於lockset與happens-before演算法提出硬體架構混合式偵測機制，我們發現處理同步屏障(barrier)會影響到happens-before演算法的偵測能力。因此，我們移除大部分的lockset機制，對於每個變數只保留被存取的狀態(lock state)與最後存取的線程號碼(access ID)進而提出改善式happens-before偵測機制，經過數據驗證可以達到高偵測精確度與低硬體需求之架構，為了達到高偵測精確度，我們一併提出備份與還原機制用於解決偵測資訊(metadata)被快取剔除問題。

我們採用十支SPLASH2程式來評估我們所提出的兩種偵測機制，透過模擬結果我們找到SPLASH2中存在有資料競爭現象，並且透過備份和還原機制大幅提高偵測能力，改善式happens-before偵測機制效能負擔為一般執行時間的1.22至2.55倍。

As the multicore platform becomes more and more widespread, programmers usually adopt multithreaded programing to improve the performance. However, multithreaded applications are prone to cause synchronization bugs, such as data races. Unfortunately, existing software race detectors are slow in performance while the published hardware-assisted race detectors are imprecise in reporting data race events.
In this thesis, we propose two hardware-based data race detection mechanisms to catch synchronization bugs in a multicore system. We first develop a hardware implementation of a hybrid-based data race detection mechanism based on the lockset and happens-before algorithms. We find that the way this hybrid detection mechanism handles the barriers adversely affects the detection capability of the happens-before. We remove most of the storage and mechanism in lockset and only keep the lock state and access ID for each variable. Based on this, we propose the improved happens-before detection mechanism which is proved to be a precise data race detector and has less cache area requirement. To be precise in data race detection, we also develop the backup and restore technique to eliminate the cache eviction problem for the cached metadata.
We evaluate the two proposed detection mechanisms by ten SPLASH2 benchmarks. Through the simulations, we have found the existing races in SPLASH2 benchmarks and our method has significantly enhanced the detection capability due to the employment of the backup and restore technique. The improved happens-before detection mechanisms has caused about 1.22x-2.55x of overheads compared to the normal execution time.

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