Root cause of crashes was thread safety: libdeflate's decompressor struct
has mutable decode tables rebuilt per-block, so sharing between main thread
and FMOD audio thread caused wild writes. Fixed with a thread-local pool
keyed by Windows thread ID (FS:[0x24]).
Switched build ABI from msvc to gnu — eliminates stub headers, libdeflate
uses Zig's bundled MinGW libc. Relaxed zlib header filter from == 0x78 to
(CMF & 0x0F) == 0x08 to catch both 32K and 4K window sizes.
Benchmarked: stock=2681ms, per-call-alloc=1304ms (2.05x), tls=1194ms (2.2x)
on 84k calls. Zero errors, zero fallbacks in production.
DecompressData_WithOptions modifies the input buffer during overlap
handling. Our hook must save the input before calling the original,
then pass the saved copy to libdeflate. Also documents all compression
types, function signatures, and bugs found during integration.
libdeflate sanity test passes (hello → hello, cpu_features=0x8000001F).
All 93K decompression calls during loading are pure zlib (type 0x02).
Header bytes 78 9C confirm standard zlib-wrapped deflate. No PKWare,
bzip2, or ADPCM observed.
Volume: 170MB compressed → 380MB decompressed in 2.9s during loading,
~5K calls/period during gameplay.
Format: [0x02] [zlib_stream...] — straightforward for libdeflate.
Previous crashes were from reading out_size AFTER original modified it
and from writing to out_buf unsafely.
Hooks DecompressData_WithOptions (0x661A80) to run both the original
zlib inflate and libdeflate on the same data. Times both, logs the
comparison every ~450 frames, counts mismatches.
malloc/free provided via game's Storm memory manager (SMemAlloc/SMemFree)
since we link without libc on the msvc target.
libdeflate compiled with -g0 to avoid .debug_frame COFF section name
warning. AVX-512 disabled (32-bit), SSE2/AVX2 paths active.
Vendored libdeflate decompress-only C sources into src/performance/.
Compiled as static lib (x86-windows-gnu for libc headers), linked into
the DLL. AVX-512 disabled (not available on 32-bit x86), SSE2/AVX2
paths active.
Target: replace WoW's embedded zlib inflate (~3% CPU) with libdeflate's
~2.3x faster implementation. Hook integration next.
- performance module default=true, transform44 and silicon default=false
- Silicon JMP patches (22 functions) moved into performance.zig directly
- Single flag: 'zig build' gives all optimizations, zero profiling
- Dev mode: 'zig build -Dtransform44=true' for A/B testing
Clean module at src/performance/ with all verified permanent
optimizations and zero profiling overhead. No rdtsc, no A/B testing,
no probe counters, no dumpStats.
Hooks: transformMatrix4x4 bone SSE, RenderParticleSprites SSE,
GetOrCreateCharacterGlyph cache, OnWorldUpdate cache reset,
teardown guard.
SSE compilation units (bone_sse, particle_sse, clip_sse, silicon_sse)
moved to src/performance/ as canonical location.
Build: zig build -Dperformance=true -Dsilicon=true
(transform44 module remains available for profiling/development)
MarcelineVQ