Helium: Lifting High-Performance Stencil Kernels from Stripped x86 Binaries to Halide DSL Code

Highly optimized programs are prone to bit rot, where performance quickly becomes suboptimal in the face of new hardware and com-piler techniques. In this paper we show how to automatically lift performance-critical stencil kernels from a stripped x86 binary and generate the corresponding code in the high-level domain-specific language Halide. Using Halide’s state-of-the-art optimizations tar-geting current hardware, we show that new optimized versions of these kernels can replace the originals to rejuvenate the application for newer hardware. The original optimized code for kernels in stripped binaries is nearly impossible to analyze statically. Instead, we rely on dynamic traces to regenerate the kernels. We perform buffer structure recon-struction to identify input, intermediate and output buffer shapes. We abstract from a forest of concrete dependency trees which contai