d4r/docs/windows-rdna4-port.md

Windows / RDNA4 port

Branch: windows-rdna4. Target: Windows 11 x64, RX 9070 XT, gfx1201. Priority: correct K, correct M, native Windows, same-frame output, then speed. This is a work log for an implementation in progress, not a claim of DLSS support.

Milestone and gates

Current milestone: M1/M2/M4/M5 passed; NGX init + DLSS CUDA capability discovery passed with the user's DLLs. The first K enc1 code object compiles and loads; its prep/transformer have not yet been executed or checked against replay. Do not integrate NGX until the integer PTX workload is stable on the real GPU.

Gate	Status
M0: branch, audit, Windows build and diagnostics	Initial implementation complete
M1: native HIP gfx1201 allocation, kernel, CPU verification	PASS, 32 iterations + guard verification
M2: Windows ZLUDA integer PTX, primary and created contexts	PASS, 32 iterations each + guard verification
M3: Windows NGX initialization and simple DLSS path	Init + SR capabilities PASS; Evaluate/transformer pending
M4: D3D12 / HIP external memory and fence round trip	PASS with TheRock; stable 7.2 has mapped-view leak
M5: independently validated gfx12 WMMA backend	PASS: raw + legacy adapter, 16 cases, max abs/relative error 0
M6: K layers, full transformer and image validation	Pending
M7: M FP16-equivalent baseline and full transformer	Pending
M8: standalone Windows D3D12 NGX harness	Pending
M9: OptiScaler integration, profiling, installation	Pending

Source baseline (checked 2026-09-29)

• d4r: ed1ab60, main, 14 commits; https://github.com/countervolts/d4r.
• ZLUDA master: ee2f25a180099fa42f36b2346732e1f2470a03ad, 2026-09-22. This is also the base named by d4r's existing patches.
• Windows binary baseline: ZLUDA v7-preview.11, zluda-windows-ee2f25a.zip, SHA256 7788c1ed43385e62f0cc5f4d1aead24c92b671c02f1d685f63182540dea16d74.
• Local HIP SDK: C:\Program Files\AMD\ROCm\7.2, headers report 7.2.60201, commit 38d754472. Compiler: AMD clang 21, LLVM commit 590b9320a5be90e40268759c6203c01fde121e68.
• Keep stable SDK and TheRock installations separate. Select one directory per build and test run; never mix headers, import libraries, runtime or COMGR.
• Tested isolated TheRock core: 10.2.0a20260929, HIP 7.17.26386, commit 0ad5f73253; wheel SHA256 9623b97ca511eaa176905075a504393eca6fde594222af10b55e4fb1edfe5a25. No machine-wide runtime replacement is performed.
• CMake 3.31.6, Ninja 1.11.1 (Python package 1.11.1.4).
• Windows host toolchain: LLVM-MinGW 20260922, UCRT x64, SHA256 e3ad77d117a4bea19a7a3b333341824d79a5a371004a10e25b8504e7b3047666. This is a portable fallback on this machine, where MSVC is not installed. The device compiler remains the selected AMD HIP clang.

Architecture and platform boundaries

Existing path: D3D12 -> OptiScaler -> d4r shim -> NGX CUDA -> Wine nvcuda -> ZLUDA -> HIP. The shim records Vulkan copies through vkd3d-proton interop. A patched vkd3d splits recording into submissions and gates the second part on a semaphore. The Wine bridge translates Windows/SysV ABIs, loads Linux libraries, chooses native kernels from KFD topology and performs fd-based Vulkan memory imports.

Planned Windows path: D3D12 -> OptiScaler -> d4r shim -> NGX CUDA -> Windows ZLUDA -> HIP gfx1201. Platform-independent NGX parameter handling, formats, references, replay format and kernel identity checks should be retained. A Windows backend must use Win32 DLL loading, HIP device properties, shared D3D12 allocations and fences. Wine builtins, KFD, file descriptors, Proton and vkd3d are excluded from runtime.

An NGX Evaluate call receives a recording command list, not a queue that can be submitted halfway through by the shim. Native D3D12 has no equivalent to the vkd3d split extension. Same-frame synchronization therefore needs an explicit submission boundary supplied by the harness and then OptiScaler/queue integration. A HIP wait inserted behind an unsplit D3D12 submission can deadlock. Merely mapping VRAM does not solve command recording/submission ownership.

Audit map and decisions

• README.md, docs/{architecture,building,native-kernels,performance}.md: Linux-tested baseline; upstream K translation can produce nonfinite results. A successful NGX return alone is not transformer validation.
• tools/d4r_nvngx_shim.cpp: Windows API/NGX entry points and C++ worker are reusable; Vulkan resource conversion, markers and split-frame functions form the platform boundary. Portable ini paths currently assume Wine translation.
• tools/wine_nvcuda_bridge.c: loading (dlopen, pthread_once), KFD target selection, descriptor bookkeeping, PTX manifests, replay/profile and CUDA forwarding are interleaved. Preserve identities/instrumentation, replace platform services rather than copy the Wine bridge into Windows.
• patches/zluda/0002: DLSS arrays/textures/surfaces, PTX instructions, dumps; 0003: bounds and gfx11 MMA; 0004: native override/prep, FP8, extra bitcode, handoffs; 0005: null texture reads. The gfx11 MMA optimization is explicitly architecture-gated. It must not be enabled for gfx12 by changing that gate.
• patches/vkd3d-proton/0001: submission split, not a portable D3D12 interface.
• kernels/k: pwin_common.h, layer/position/wide templates and eleven entries. Operands are replicated 16-half rows; accumulator row is 2*i + (lane>>4); operand_from_dt, wtile, weight prep and stores depend on that convention.
• kernels/m: swin_common.h, swin_block.h, five standalone entries; FP8 weights expanded to FP16, kslot, woff, bload, k32, accumulator reconstruction and xor shuffles need layout audit. Preserve rounding per k32.
• kernels/tex: enc0 tail/dec0 head also use gfx11 WMMA and output shuffles; changing only K/M would leave part of M incorrect. Generated PTX is private.
• kernels/build.sh, texture build and scripts/build_zluda_ptx_helpers.sh: Linux tool paths, shell, bitcode cleanup and target assumptions need a Windows build path. Keep existing Linux scripts operational.
• kernels/tools/{pwin_model,swin_model,ptxsim,psnr,kernel_manifest}.py and dump_runner.cpp, tools/replay_dlss_*: use existing reference semantics and capture relocation format; add finite checks and quantitative comparison.
• scripts/package_release.sh, install/launch scripts and packaging/: Linux release bundles Proton components. Windows diagnostics/package must be separate and must never include NVIDIA DLLs or extracted NVIDIA PTX/weights.
• Upstream ZLUDA already has Windows delay-loading for HIP 7 and fallback HIP 6. Its Rust binding calls versioned hipGetDevicePropertiesR0600; a reported gfx1201 crash is not evidence of an ABI bug without a reproducer/trace here.

gfx11 versus gfx12 WMMA

For wave32, gfx11 FP16 A/B are 16 halves per lane with replication across the two 16-lane groups. gfx12 uses 8 halves per lane without replication. The gfx12 builtin has a _gfx12 suffix; its FP32 accumulator is still eight floats, but rows are contiguous within the lane group, rather than gfx11 even/odd rows. The backend must explicitly convert operands and accumulator distribution, or update all dependent loads/stores and intermediate fragments together. Start with FP16 / FP32 accumulate. M native FP8 is a later measured optimization. Compile success is not proof of lane layout or numerical correctness.

kernels/common/wmma_backend.h now preserves the gfx11 call and maps d4r's 16-half operand / even-odd accumulator contract to gfx12's 8-half operand / contiguous accumulator contract. The gfx12 mapping uses an unconditional wave32 half-exchange for every source fragment element before selection. Performing the exchange only on lanes selected by a group-dependent branch returned channel 9 in place of channel 1 on this card: the opposite half of the wave was inactive at that instruction. This was caught by the CPU reference. tools/windows/wmma_gfx1201.hip tests raw gfx12 WMMA, the adapter, the half-exchange and lane ID with nonzero accumulator and one/two K16 steps. Both stable HIP 7.2 and TheRock 10.2 produced exact 16x16 outputs across 16 different inputs; max absolute and relative errors were both zero.

kernels/k/pwin_common.h now calls the tested adapter. The Windows device-only compiler uses kernels/common/hip_device_minimal.h, exposing only public Clang AMDGPU work-item/grid/barrier builtins and HIP-compatible qualifiers; the ordinary Linux HIP include path remains. CMake builds enc1 for gfx1201 into experimental/k/ and verifies that HIP loads both prep and transformer entry points. This is a compile/load smoke test, not K layer correctness or DLSS execution. The code object must stay out of ZLUDA's native override path until numerical K replay validation passes.

External interop blockers

The installed HIP headers define D3D12Resource/D3D12Heap external memory and D3D12Fence external semaphore types. Their presence is not proof the Windows runtime implements them. Validate imports, mapping, GPU waits/signals and cleanup using an independent round trip before modifying the shim. Use HIP/DXGI device identity to prevent importing allocations across adapters. NT HANDLE ownership must be explicit; Win32 import is not fd ownership transfer. Test repeated create/destroy cycles as upstream noted a mapped-buffer leak on Linux ROCm. CPU verification copies are allowed in tests, never in the fast path.

Implemented independent test: DXGI LUID matches HIP, an R32_UINT texture is copied to a shared DEFAULT-heap linear buffer in VRAM, HIP maps that D3D12 resource, checks every input element and XORs it, D3D12 copies it back to the texture and finally to a readback buffer solely for test verification. Shared D3D12 fence values sequence both queues within the same iteration. There is no CPU data copy between the APIs; native tiled texture import is not yet tested. The future shim needs GPU texture/linear conversion or validated direct arrays. The caller closes its original NT HANDLEs after HIP releases imports.

Stable HIP SDK 7.2.60201 fails mapped-buffer lifetime testing. resource and import modes are stable, but map leaks one HANDLE and 262144 bytes per cycle. The runtime's extra view->retain() is the cause; AMD removed it in CLR commit 529f6b1. The source backport is retained at patches/rocm/0001-external-memory-view-ownership.patch. No pointer/refcount or DLL binary hacks are used. Current TheRock passes both the 64-cycle map lifetime test and the 32-cycle synchronized texture round trip. The runner automatically isolates resource/import/stream lifetimes on failure. Do not declare stable SDK 7.2 acceptable for the leak-free fast path.

Windows NGX initialization

tools/windows/ngx_cuda_init_probe.cpp retains the physical HIP/PCI device check, initializes a ZLUDA primary context, loads the user-supplied DLLs, discovers DLSS CUDA capability and tests the existing MSVC parameter accessor. This does not create/evaluate a DLSS feature or assert transformer correctness.

The supplied driver _nvngx.dll 32.0.16.1714 uses the driver/snippet three-argument NVSDK_NGX_CUDA_Init(appId, dataPath, sdkVersion) ABI. The four-argument SDK client interface used by the upstream shim passes a pointer as the version and returns 0xBAD0000C (OutOfDate) for this binary. The two interfaces are distinguished in NVIDIA's public nvsdk_ngx.h by NGX_SNIPPET_BUILD. The Windows backend must keep this distinction. The probe has explicit --ngx-abi driver (default) / sdk; it does not guess and retry.

Upstream Windows ZLUDA NVAPI lacks physical GPU enumeration, architecture and logical GPU/LUID functions used by NGX. The compatibility target nvapi-compat/nvapi64.dll implements those public NVAPI APIs through HIP; unknown queries are logged and forwarded to the supplied ZLUDA NVAPI backend. It validates version/size and includes NV_LOGICAL_GPU_DATA_V1.reserved[8] (568-byte x64 ABI). Concurrent initialization is synchronized. The AD102/AD100 identity is explicitly a CUDA/NGX network profile matching d4r's sm_89 kernels; physical detection and native compilation remain gfx1201. It is currently a probe backend, not a complete game-wide NVAPI replacement. A separate nvapi-trace build forwards every response unchanged for diagnosis.

Driver init's default feature search needs the DLSS DLL next to the executable. The runner creates a unique private %TEMP%/d4r-ngx-<GUID> directory containing the probe and copies of the two supplied DLLs. Paths and original hashes/versions are logged; the directory is removed after the subprocess ends. Neither DLL is placed in dist/, git, or the diagnostics ZIP. No private NVAPI function is invented and no NVIDIA binary is patched.

References: NGX API signatures, public NVAPI ABI, public NVAPI interface IDs.

Authoritative references

• AMD HIP SDK Windows support matrix lists RX 9070 XT as gfx1201 with runtime and SDK support, release 7.2.0.
• ZLUDA Windows SDK setup distinguishes official SDK and TheRock nightlies.
• ZLUDA build, trace instructions.
• LLVM AMDGPU target guide, Clang AMDGPU builtins.
• AMD RDNA4 matrix cores, RDNA4 WMMA guide, RDNA4 ISA.
• TheRock Windows development.

Build, test, package

Run from the repository root in PowerShell. The setup installs tools only inside .tools, verifies downloaded SHA256 values, and does not install a driver/SDK.

powershell -NoProfile -File scripts/windows/setup-windows-tools.ps1
powershell -NoProfile -File scripts/windows/build-windows-rdna4.ps1
powershell -NoProfile -File scripts/windows/test-windows-rdna4.ps1

For the currently validated external-memory runtime, use the separate profile:

powershell -NoProfile -File scripts/windows/setup-windows-tools.ps1 -RuntimeProfile therock
powershell -NoProfile -File scripts/windows/build-windows-rdna4.ps1 -RuntimeProfile therock
powershell -NoProfile -File scripts/windows/test-windows-rdna4.ps1 -RuntimeProfile therock

This builds into build/windows-rdna4-therock and installs into dist/windows-rdna4-therock. The stable profile stays available for reproducing the runtime bug. It is expected to return failure at the lifetime gate.

One command adds the local NGX initialization gate after the seven hardware gates:

powershell -NoProfile -File scripts/windows/test-windows-rdna4.ps1 -RuntimeProfile therock -NgxCore "C:/Users/Administrator/d4r/_nvngx.dll" -DlssDll "C:/Users/Administrator/d4r/nvngx_dlss.dll"

Success requires all eight tests and PASS NGX_INIT ... sr_available=1; transformer_executed=0 is explicit. On NGX failure, CUDA trace and NVAPI query logs are collected automatically. NVIDIA DLLs remain local test inputs.

The build accepts -HipRoot, -ZludaRoot, -ToolchainRoot, -BuildDirectory and -InstallDirectory. MSVC users can invoke CMake from a Developer Shell without the portable MinGW compiler. Equivalent direct build:

cmake -S . -B build/windows-rdna4 -G Ninja -DCMAKE_BUILD_TYPE=RelWithDebInfo "-DD4R_HIP_ROOT=C:/Program Files/AMD/ROCm/7.2" "-DD4R_ZLUDA_ROOT=C:/path/to/zluda"
cmake --build build/windows-rdna4
ctest --test-dir build/windows-rdna4 --output-on-failure
cmake --install build/windows-rdna4 --prefix dist/windows-rdna4-diagnostics

The one-command diagnostic runner is also installed at dist/windows-rdna4-diagnostics/test-windows-rdna4.ps1. It requires the selected HIP SDK and ZLUDA directory; the developer setup auto-discovers local defaults. Success: exit 0, all five tests passed in summary.json, PASS HIP, PASS CUDA, PASS INTEROP_LIFETIME and PASS INTEROP in stdout. Failure: send the single printed ZIP path; it contains stdout/stderr, timeout/exception exit code, DLL paths/versions/hashes, driver/OS inventory and a minidump for an unhandled exception. Upstream trace is attempted automatically on CUDA failure when trace/nvcuda.dll is available. The trace DLL forwards to the real DLL through ZLUDA_CUDA_LIB; explicit loading no longer bypasses the trace by accidentally passing the real DLL to the launcher.

The HIP module compiler uses the selected SDK, fixed --offload-arch=gfx1201, wave32 and no host/device library dependency. Host code uses the installed HIP header ABI and loads that SDK's amdhip64_7.dll by absolute path. CUDA loads the provided ZLUDA DLL by absolute path, matches the adapter against HIP PCI identity, tests two context lifecycles, JITs embedded PTX and verifies an integer pattern and out-of-range sentinels. No CUDA SDK is required.

No NVIDIA DLL is needed for M1/M2. Later NGX tests accept user-supplied absolute paths; NVIDIA software is never downloaded or added to git by these scripts.

Known limitations and results

2026-09-29: installed hipInfo.exe passed device enumeration in this workspace: RX 9070 XT, gfx1201, warpSize 32, 15.92 GiB total, 15.77 GiB free. 2026-09-29 hardware results: Windows 11 Pro 10.0.26200, AMD display driver 32.0.31041.1004, HIP runtime/driver API 70260201. HIP struct size 1472 bytes; physical device PCI 0000:03:00. Native HIP module: 32 successful iterations, 4099 elements with changing launch counts and seeds, guard verified. CUDA PTX: 32 iterations each in primary/created contexts, same pattern/guards verified, all context/module/memory teardown calls successful. ZLUDA binary SHA256 51dd32dc116a6c14c7a4bf5acf620bba0546ca7ec5f8a6e2148dd68f1714b165. Logs: local test-results/m1-m2.zip; ignored by git.

2026-09-29 M4: TheRock profile passed all HIP/PTX checks plus D3D12/HIP round trip (32 iterations, 16384 elements each), exact integer output and GPU fence synchronization. Map lifetime: 64 import/map/free/destroy cycles, HANDLE count 267 after both warmup and the last cycle, free VRAM 16926011392 bytes throughout the measured steady state. Full interop cycle HANDLE count also stays constant after warmup; stream teardown lowers it. Recreating streams did not resolve the stable runtime mapped-view bug; the fix is the runtime ownership correction.

Local proprietary inputs supplied by the user: nvngx_dlss.dll 310.9.1.0, _nvngx.dll 32.0.16.1714. Neither is packaged or tracked.

2026-09-29 NGX initialization: PASS on gfx1201 with those two DLLs and the native NVAPI topology backend. SR Available=1, FeatureInitResult=0x1, NeedsUpdatedDriver=0, MSVC parameter roundtrip Width=640, checked parameter/context/NGX cleanup. Local logs: test-results/ngx-init-private-runtime.zip. This is only the first part of M3; feature execution, K/M correctness and the Windows shim remain open.

2026-09-29 M5: TheRock full diagnostic run including user-provided NGX DLLs: 8/8 gates PASS (test-results/m5-k-module.zip). CTest: 7/7 PASS. Stable HIP 7.2: 5/5 non-interop gates PASS (HIP, gfx12 WMMA, K module load, both CUDA contexts); stable mapped-view lifetime bug still excludes its interop fast path. WMMA raw and legacy-layout adapter each match the scalar reference exactly over 16 changing input matrices, with both one-step and two-step accumulation. The enc1 K module is built and loaded on gfx1201, with functions resolved; transformer_executed=0 is explicit in the module probe. Neither K nor M transformer correctness is claimed yet. The same K source also compiles for gfx1101 through the unchanged gfx11 builtin branch (compile-only regression; no RDNA3 GPU is present in this Windows machine).

Audit found an upstream validation blocker: swin_model.py imports model_enc3, which is absent from the repository. M reference validation needs that dependency restored or an independently checked replacement.

Environment-specific issues resolved: sandbox disallows writes to .git and launching the MinGW child compiler, so branch/commit/build require scoped tool approval in this managed environment. HIP_PATH ends in a backslash; build script normalizes it before PowerShell 5 argument quoting. Test runner uses .NET Process to retain reliable exit codes and concurrently drain both diagnostic streams. No end-to-end K/M/DLSS/OptiScaler support is claimed by these diagnostic milestones.