[Const-me]

> Isn't this exactly what a GPU firmware is expected to do?

The source data needs to appear on the GPU somehow. Similarly, the results computed on GPU are often needed for CPU-running code.

GPUs don’t run an OS and are limited. They can’t possibly access file system, and many useful algorithms (like PNG image codec) is a poor fit for them. Technically I think they can access source data directly from system memory, but doing that is inefficient in practice, because GPUs have a special piece of hardware (called copy command queue in d3d12, or transfer queue in Vulcan) to move large blocks of data over PCIe.

That library implements an easier way to integrate CPU and GPU pieces of the program.