The GPU layer (gpu/) is the port's own code: command processor (cp/), GCN hardware definitions
(gcn/), shader translator GCN -> SPIR-V (shader/), renderer (render/), buffer and texture caches
(buffers/, textures/), memory tracking (memory/), platform libraries (platform/), upscalers
(upscale/). It started from shadPS4 (https://github.com/shadps4-emu/shadPS4, commit
b4e7ae776071ceb1dd35004577a8719481e1d258, GPL-2.0-or-later) and was rewritten part by part;
gpu/shadps4 was removed on 2026-10-13. The shader translator was checked against the shadPS4
translator it replaced on a corpus of the game's shaders (byte-identical SPIR-V,
tests/test_shader_corpus.cpp).

The online module (gpu/bbnet20) keeps shadPS4 v0.20.0's network, NP and shadNet code
(bbnet20/vendor/shadps4, SHADNET-PORT.md).

Third-party libraries in third_party/: sirit (SPIR-V emitter), gcn (AMD GCN headers), half,
httplib, imgui, fonts, amd-fsr1 (FidelityFX headers used by shaders), fsr-vulkan.
