LOST or Load to Store sequences in handheld app executions are generic acceleratable sequences of instructions. Unlike the domain specific acceleration units or IPs found in modern handheld SoCs such as video codecs, camera interfaces etc., LOSTs capture the intrinsically common sequences of instructions found in all handheld app executions. Our IISWC ’17 paper lists 5 most common LOST sequences found in handheld apps. The resources below provides a more comprehensive list of LOST that we found in 10 handheld app characterization.

LOST Sequences found in 10 handheld apps

Can we make a common acceleration unit out of them?

Yes. A schematic diagram for accelerating the highlighted LOSTs in the above table is shown below:

Such LOST accelerators can also be integrated with the CPU data path as described in our paper.

Framework source code for finding LOSTs

The framework to find LOSTs in app execution and a sample trace is found in Github GemDroid.


Prasanna Venkatesh Rengasamy

Haibo Zhang

Nachiappan Chidambaram Nachiappan

Shulin Zhao

Anand Sivasubramaniam

Mahmut T Kandemir

Chita R Das


Characterizing Diverse Handheld Apps for Customized Hardware Acceleration, IISWC 2017.