Every run recompiled every shader: the recompiler's variant cache and
the device's VkPipelineCache only lived in memory, and the first frames
of a title spent hundreds of milliseconds per large program in the
front end, the emitter and the optimizer.
Compiled variants (the SPIR-V plus the compiled shader info and binding
allocation that per-snapshot binding population needs) are now stored
on disk, one file per key, written atomically by a background thread,
and a later run loads them instead of compiling. The key holds every
input the in-memory variant cache matches on: the in-memory recompile
key (stage, code hash, stage registers, user data count, target), every
code word, the host subgroup size, the binding layout, the resource
specialization, and the values of the APS5_* switches the recompiler
sources read (found at build time; switches that only report are left
out). Entries live under a directory per source version, a build-time
hash of the recompiler and AGC driver sources and the build
configuration, and carry their key and checksums: an entry whose
format, version, key, size or checksum does not match, or whose payload
does not decode exactly, is ignored and recompiled. Directories no
build used for two weeks and stale temporary files are removed. Requests
under the debug probe bypass the disk cache.
The device's VkPipelineCache is loaded at creation when the file's
checksum and Vulkan header match the device (vendor, device and
pipelineCacheUUID; the driver version is in the file name), saved every
10 s while it grew, and saved at teardown.
Location: a shader_cache folder beside the running executable (not the
working directory), so the relinked game stays a self-contained folder;
ANYPS5_SHADER_CACHE_DIR overrides it. ANYPS5_NO_SHADER_CACHE=1 turns both caches off; the AGC
tests run with it set so they never write to the user's cache.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ButHENCbXXt8h4EZuWUabJ
SamG-Coder
Dean Galvin