[loop0]

Honest question: why these gpu drivers need some many lines of code? Anybody with more background can explain?

[detaro]

GPUs are complex computers in themselves, and the driver needs to provide compilers etc that target them (e.g. when it comes to shaders, applications hand the driver source code that is then compiled for the specific GPU architecture). Combine that with many different product generations and configurations being supported, code apparently being autogenerated and thus probably not optimized for size and you get to this.

EDIT: monocasa points out below that the compiler is not a correct example - true, that does live in e.g. mesa userspace code.

[bleepblorp]

GPU drivers are essentially operating systems for the GPU.

[extropy]

And also ~real time compilers for any user code (shaders, etc) that will be running on the GPU.