HPVM-HDC: A Heterogeneous Programming System for Hyperdimensional Computing

Hyperdimensional Computing (HDC), a technique inspired by cognitive models of computation, has garnered significant interest in recent years. For example, HDC has been proposed as a more efficient and robust alternative basis for machine learning. The highly parallel nature of HDC algorithms makes them well-suited for execution on several hardware architectures, including CPUs, GPUs, FPGAs, ASIC-based and Resistive RAM-based accelerators. Traditionally, these diverse architectures are programmed using different languages and programming models, making heterogeneous programming for HDC prohibitively difficult. To make matters worse, currently no compiler framework that enables heterogeneous compilation of HDC programs and generates efficient code for a wide variety of hardware targets exists. We propose an end-to-end heterogeneous programming system for HDC: a novel programming language, HDC++, that enables programmers to write programs using a unified programming model, including a set of high-level, HDC-specific, abstractions to ease programmability; and a heterogeneous compilation framework, HPVM-HDC, that provides an intermediate representation that reflects the parallel character of HDC algorithms and enables compilation of HDC++ programs to a wide array of hardware targets, including a custom HD Digital ASIC and an HD Resistive RAM accelerator. HPVM-HDC can perform HD specific optimizations, which we demonstrate by implementing two domain specific optimizations. Our evaluation shows that HPVM-HDC generates performance competitive code, compared with baseline HD applications. Additionally, HPVM-HDC efficiently targets an HD Digital ASIC and an HD ReRAM accelerator simulator, achieving a geomean 1.28x and 2.15x speed-up over our compiled GPU implementations, respectively.