In this paper, we explore 6 Scratch-Pad Memory (SPM) allocation algorithms to improve performance or energy efficiency for Hybrid SPM-Cache (HSC) architectures, including 4 heuristic-based algorithms and 2 optimal algorithms based on model checking. Our experimental results show that the Greedy Stack Distance based Allocation for Energy (GSDA-E) algorithm can efficiently minimize the energy consumption and achieve near optimal performance results.