zluda: coalesce pair shadow stores, signed native FP8 conversion

Patch 0011 merges a complete accumulator-register pair overwrite into one
shadow-layout conversion (reads, rewritten shadow accesses and block
boundaries prevent it; partial writes keep read/modify/write), and requests
eight waves per SIMD for gfx12 native-FP8 functions. Patch 0012 keeps signs
in the native conversion: finite overflow clamped, NaNs mapped to signed
infinity, post-conversion sign masks gone; plain and ReLU remain
exhaustive-table identical to the software codec.

Eighty-frame harness at 720p->4K, excluding the first twenty: control
24.764 ms, coalescing 23.340 ms, plus eight waves 20.135 ms, plus signed
conversion 16.234 ms (15.144 ms with the harness idle gap removed); all
eighty saved frames byte-identical to the matching control. Twelve- and
ten-wave budgets regress (25.56/24.61 ms); fast math changes the image
(18.92 ms) and is not selected.

README.md

@@ -138,7 +138,7 @@ ROCm does not need to be installed: the zip includes its runtime (from AMD's Ubu
 
 The full sequence is in [docs/building.md](docs/building.md). In short:
 
-1. Build ZLUDA `ee2f25a` with `patches/zluda/0002`–`0008` applied, including its `d4r_emit` example for offline texture builds.
+1. Build ZLUDA `ee2f25a` with `patches/zluda/0002`–`0012` applied, including its `d4r_emit` example for offline texture builds.
 2. Build the patched vkd3d-proton: `scripts/build_vkd3d_proton_d4r.sh OUT_DIR`.
 3. Build the shim and bridge: `scripts/build_d4r_nvngx_shim.sh`, `scripts/build_wine_nvcuda_bridge.sh`.
 4. Stage the runtime with your NVIDIA files: `scripts/install_d4r_runtime.sh _nvngx.dll nvngx_dlss.dll`.