Learning Performance Optimization from Code Changes for Android Apps - Feng, Ruitao; Meng, Guozhu; Xie, Xiaofei; Su, Ting; Liu, Yang; Lin, Shang-Wei (2019 IEEE International Conference on Software Testing, Verification and Validation Workshops (ICSTW), Software Testing, Verification and Validation Workshops (ICSTW), 2019 IEEE International Conference on, 2019)