Commit Graph

12 Commits

Author SHA1 Message Date
MechaCat02
da7c29b6d2 [iterate-3V] Fix logo texture: map texture-fetch physical base onto backing window
The publisher-logo texture (K8888 1280x768 linear, `E59B2B3D`'s tfetch
surface) rendered flat/transparent because the GPU texture decode read
the wrong host bytes — NOT because the asset was never decompressed.

First-divergence (vs canary, measured both engines):
- Ours DOES read game:\hidden\Resource3D\*.xpr in full, builds a
  byte-identical cache, decompresses the logo, and CPU-writes the real
  artwork (~839K nonzero bytes) into the texture buffer — at the guest
  physical-aperture VA 0x4dbee000 (writer sub_823C3E70 @ 0x823c3f8c).
  This REFUTES the iterate-3U verdict that the texture was never filled.
- BUT the GPU decode used the raw fetch-constant base 0x0dbee000 as a
  virtual address. In ours' flat 4GB memory, virtual 0x0dbee000 and the
  physical alias 0x4dbee000 are DIFFERENT host bytes (no aliasing in the
  read/write path), so the decode read all-zeros.

The Xenos texture fetch constant carries a guest *physical* base; the
CPU writes texels through its cached-physical aperture, which ours backs
at the committed 0x4000_0000 window. Map the base via the existing
`physical_to_backing` helper before reading — exactly as the vertex
fetch path (draw_capture.rs, iterate-3Q) and as canary reads textures
through its GPU shared memory (= physical).

Measured after fix (env-gated probe, removed): the logo decode reads
base=0x4dbee000 and produces 839068/3932160 nonzero bytes (21.3%) — a
centered logo on a transparent field, matching canary's ~21% exactly.

Determinism: GPU-side pure read; no CPU/guest-memory state changes. The
n50m --gpu-inline --stable-digest golden is byte-identical (verified 2x,
texture_cache_entries unchanged). cargo test --workspace green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-18 18:07:00 +02:00
MechaCat02
1b9918450f [iterate-3T] Real UV interpolation + per-draw textures: shader/UV/bind chain complete
Build the full texture-sampling chain for the publisher splash so the textured
logo CAN sample real artwork at the guest's real UVs. Measured with an env-gated
frontbuffer readback (since removed): the chain is correct end-to-end, but the
sampled K8888 1280x768 texture is ALL-ZERO in the UI window's reachable boot
range — the artwork is produced by an EDRAM resolve (RT->texture copy) that ours
does not yet perform (resolves=0). So this lands the correct shader/UV/bind work
and isolates the remaining blocker to the resolve gap, not the shader path.

Translator (xenia-gpu/src/translator.rs), all UI-translator-only:
- Real Xenos export-index model (replaces the AllocKind heuristic that collapsed
  every VS export to one color slot and DROPPED the texcoord). When export_data
  is set the 6-bit vector_dest IS the export index: VS 62=oPos, 0..15=interps;
  PS 0=RT0. The logo VS exports oPos(62), interp0(color), interp1(UV) distinctly.
- Real interpolator passthrough: VsOut carries 8 interpolator locations; the PS
  seeds r[i] = in.interp[i] (Xenos PS-input-GPR mapping) so tfetch samples at the
  real interpolated texcoord (r1) instead of (0,0).
- vfetch format 6 (k_16_16) packed-16 unpack + per-attribute dword offset, so the
  3 vfetches sharing one fetch-constant (pos/UV/color in a 6-dword vertex) read
  the right attribute. Previously rejected the whole logo VS to the interpreter.
- QuadList/RectangleList host->guest vertex-index remap in the VS (replay is
  non-indexed): QuadList 6 host verts -> guest [0,1,2,0,2,3] (full quad).

fetch.rs: decode vfetch `offset` (dword2[8:15], dwords), `is_signed`,
`is_normalized`.

Per-draw textures: DrawCapture carries the decoded texture(s) (keyed off the
active PS's tfetch slots, attached in gpu_system after decode);
render.rs::dispatch_xenos_captures uploads + binds each capture's texture via the
host texture cache before its draw, instead of one last-draw primary_texture.

Determinism: all changes feed only the UI translator/capture path; frame_captures
is None headless. `check -n50m --gpu-inline --stable-digest --expect` byte-
identical (exit 0). 681 tests pass (+2 regression: logo VS now translates with
interpolators; PS seeds interps into registers). Temp readback/dump probes removed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-18 17:12:16 +02:00
MechaCat02
504592ac13 [iterate-3O] Real-render slice: replay guest geometry in --ui (Route A)
Replace the synthetic placeholder triangle in the --ui window with the
splash's REAL guest geometry, proving the faithful-render pipe end to end.

Architecture: Route A (UI-side replay). A per-draw capture channel carries
each PM4_DRAW_INDX*'s real state to the UI, which replays it through the
existing wgpu Xenos pipeline. The deterministic headless core is untouched:
capture is gated on an Option<Vec<DrawCapture>> that is None in headless
mode and only enabled on the --ui path, so the --gpu-inline n50m golden is
byte-identical (verified 2x).

The hard part was sourcing real vertices. The WGSL VS already does
format-aware vertex fetch from the b4 storage buffer at the address from the
fetch constant -- but b4 was never populated and the fetch address is an
absolute guest dword address. The slice:
  * xenia-gpu/draw_capture.rs: parse the active VS, find its first vertex
    fetch, read that fetch constant, copy a bounded window of guest memory
    at the fetch base. Best-effort: has_real_vertices=false falls back to
    procedural geometry (never fabricated pixels).
  * gpu_system.rs: accumulate one DrawCapture per draw into frame_captures.
  * exports.rs (vd_swap): drain + publish the frame's captures to the UI.
  * ui_bridge/bridge.rs: new publish_geometry channel + UiHandles.geometry.
  * WGSL (interp + translator): rebase the absolute fetch address by a new
    DrawConstants.vertex_base_dwords so it indexes the uploaded window.
  * render.rs: dispatch_xenos_captures uploads each draw's real vertex
    window + matching shader, issues real DrawRequests (real prim type,
    host vertex count, vs/ps keys).
  * app.rs: prefer the real-capture replay; HUD adds real-geo=N counter.

Verified in --ui on Sylpheed: "first Xenos capture batch replayed (real
geometry) captures=24 real_vertex_draws=24" -- all draws resolved a real
guest vertex window; WGSL compiles; no validation errors over 1616 swaps.

Still synthetic-free but not yet pixel-perfect: textures/UVs, DMA index
buffers (auto-index only for now), and kCopy resolve routing are staged
for follow-ups. Faithful: real vertex data, prim types, shaders, constants.

cargo test --workspace green; n50m golden unchanged (2x byte-identical).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-17 22:38:46 +02:00
MechaCat02
2f55d1fd7d [iterate-2X] Texture pipeline: un-stub RectangleList + draw-time texture decode
Two faithful, deterministic GPU-backend changes that make the texture path
correct for whatever textured draw the splash eventually dispatches. Both are
currently inert on Sylpheed (the textured logo draw is still gated downstream
— see below), but neither shifts the stable-digest golden, so they land safely.

1. Un-stub RectangleList primitive expansion (primitive.rs). The splash submits
   2819 RectangleList draws at 200M, all of which were REJECTED by the P3 stub
   (`gpu.primitive.rejected{rectangle_list}`) → only ~592 flat point/quad draws
   rasterized. Mirror canary's intent (primitive_processor.cc:389-456
   kRectangleListAsTriangleStrip) within our CPU index-rewrite idiom: emit each
   rect's 3 real vertices as one TriangleList triangle (v0,v1,v2), rejected=false,
   faithful host_vertex_count. The full quad (synthesized 4th corner v3=v0+v2-v1)
   needs real vertex fetch in vs_main — left as a documented TODO. Rejection
   warnings drop 2819→0.

2. Draw-time texture decode keyed off the active PS's real tfetch slots
   (gpu_system.rs + exports.rs vd_swap). Previously vd_swap decoded a hardcoded
   fetch-constant slot 0 at swap time. Now the DRAW handler parses the bound
   pixel shader (ucode::parse_shader), collects its tfetch fetch_const slots via
   new shader_metrics::tfetch_slots, reads each 6-dword fetch constant, and
   decode+caches it into GpuSystem::last_draw_textures. vd_swap publishes the
   first of these (UI binds one texture today), falling back to the legacy slot-0
   probe on flat-only frames. New span_max_version helper walks page_version over
   the trait (draw-time &dyn MemoryAccess lacks the heap's inherent
   max_page_version). Pure function of guest writes — deterministic.

Status: texture_decodes stays 0 on Sylpheed because all 6 live shaders are flat
(no tfetch); canary's textured logo shaders E59B2B3D/F7B1457 are not yet
dispatched by ours (a downstream title-state gate, the next frontier). The full
P5 decode→publish→upload→sample path is already wired; this makes the decode
side key off the real shader instead of a guess.

Validation: stable-digest golden sylpheed_n50m unchanged (draws=718 swaps=147
tex=0), regenerated twice byte-identical; 200M run shows 0 RectangleList
rejections. cargo test --workspace green (677, +2: rectangle_list_expansion,
tfetch_slots_extracts_texture_fetch_constants). No temp hooks. Branch only;
not pushed/merged.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 21:34:43 +02:00
MechaCat02
a91f4c550b [iterate-2W] Sustain the title present loop: viewport-size register + ISR CPU impersonation
The title's per-frame loop (sub_822F1AA8) is clock-B-paced and only re-fires
when the swap count [controller+88] changes, which advances only on source=1
CP swap-complete interrupts. Each present batch the guest submits (via the
sub_824CE348 -> sub_824BF4D0 builder) ends with a WAIT_REG_MEM on a per-CPU
swap-acknowledge fence [GCTX+0] (GCTX = [device+10772]); the GPU parks there
until the graphics ISR (sub_824BE9A0) clears that CPU's bit. Two coupled gaps
kept ours emitting only ONE source=1 then dead-locking (draws plateaued at 28,
run halted ~19.27M):

1. GPU MMIO register 0x1961 (AVIVO_D1MODE_VIEWPORT_SIZE) read as 0. The swap
   callback sub_824CE2B8 divides by its low 12 bits (display height) as a
   refresh-pacing term, so a 0 read tripped its `twi` divide-by-zero guard and
   aborted the ISR before it reached the fence-clear. Mirror canary
   GraphicsSystem::ReadRegister (graphics_system.cc:311): return 0x050002D0
   (1280x720).

2. The ISR ran on an arbitrary borrowed thread, so [r13+268] (the PCR
   processor number) did not match the interrupt's target CPU. The ISR clears
   `1 << current_cpu` from the fence; running on the wrong CPU cleared the
   wrong bit and the fence (bit 2, from cpu_mask 0x4) never reached 0. Carry
   the target CPU through the interrupt queue (bit index of the PM4_INTERRUPT
   cpu_mask for CP, 2 for vsync per canary DispatchInterruptCallback(0, 2)) and
   impersonate it on the borrowed thread's PCR around the ISR, mirroring canary
   EmulateCPInterruptDPC -> XThread::SetActiveCpu.

With both fixes the fence clears, the GPU drains each present batch, source=1
sustains per-present, clock B advances, and the loop runs continuously. Draws
climb linearly with the budget (no re-stall): 50M 28->718, 200M ->3411,
1B ->18734; swaps 2->147/950/6060. No "Unanticipated CPU_INTERRUPT" trap.
Inline-deterministic (--stable-digest byte-identical x2); n50m golden
re-baselined. 675 tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 20:49:32 +02:00
MechaCat02
873c197ff1 [iterate-2T] VdSwap: route present through ring PM4_XE_SWAP, drop out-of-band swap interrupt
Make ours' VdSwap present path faithful to xenia-canary `VdSwap_entry`
(xboxkrnl_video.cc:518-548): write the reserved 64-dword ring slot with a
PM4_TYPE0 fetch-constant patch + PM4_TYPE3(PM4_XE_SWAP) + NOP padding, then
let the natural drain consume the swap packet in command-stream order. Remove
the synthetic CP swap-complete interrupt that `notify_xe_swap` raised
out-of-band.

Root found this session (the actual present-path bug): ours' `notify_xe_swap`
pushed an `InterruptSource::Swap` (→ INTERRUPT_SOURCE_CP) interrupt directly
from the VdSwap HLE, decoupled from the GPU command stream. When that interrupt
reached the graphics ISR `sub_824BE9A0` before D3D had armed its swap-callback
slot (`[gfx+10772]+16` still the `0xBADF00D` placeholder), the ISR took its
error path and hit the assert "ERR[D3D]: Unanticipated CPU_INTERRUPT. Sign of a
corrupt command buffer?" (`bl sub_824C5DF0; twi` at 0x824BE9DC) — 2x per run on
master. Canary's VdSwap raises NO interrupt; swap-complete CP interrupts come
only from in-stream PM4_INTERRUPT packets, which are naturally ordered after the
callback-arming Type-0 writes. Routing the swap through the ring packet matches
that ordering and eliminates the trap (2 -> 0).

Canary oracle confirmation (muted, audit_mem_watch + audit_jit_prolog_pc):
canary's early/loading loop is present-driven — swap counter [gfx+15160]
(0xBE56CA38) advances ~per-vblank from vblank 65 onward, reaching 0xD02 (3330)
in ~60s via 6184 CP source=1 interrupts, with VdSwap called only ONCE. So the
present interrupts are entirely in-stream, not from the VdSwap export.

This is a correctness/faithfulness fix; it does NOT cascade. draws stay 78 at
200M and 1B because the upstream gate persists: the game submits one render
batch then stalls (renderer sub_82506xxx 0x; 2nd title thread 0x821748F0 never
spawns). The per-frame loop sub_822F1AA8 runs ~1207 iterations on vsync but
clock B (swap count) only advances ~once, so the manager update sub_821741C8
fires once. That is the iterate-2Q/2F title-pipeline gate, not a present/
interrupt bug. swaps 3 -> 4 (the in-stream PM4_XE_SWAP now drains).

Deterministic in inline mode (n50m --gpu-inline --stable-digest regenerated
byte-identical twice; golden re-baselined: swaps 3 -> 4). cargo test --workspace
675 passing.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 15:20:02 +02:00
MechaCat02
1ae472bd2b [iterate-2S] GPU: implement CP SCRATCH_REG memory writeback — arms Sylpheed's swap-callback slot
Sylpheed renders the splash (draws=78, iterate-2O) then plateaus: the
title's per-frame manager (sub_821741C8) only re-fires when "clock B"
([gfx+15160], swap count) changes, which only the CP swap-complete
callback sub_824CE2B8 increments. The graphics ISR sub_824BE9A0
indirect-calls that callback via [[gfx+10772]+16] on CP (source=1)
interrupts, but the slot stayed NULL so the callback never ran.

Root (runtime-verified, ours-side GPU): the guest arms the slot through
the Xenos CP scratch-register writeback path, which ours never
implemented. The arming IB (drained by ours at 0x4adf5180) contains a
Type-0 register write of the callback PC 0x824ce2b8 into SCRATCH_REG4
(0x057C). On hardware/canary, writing a SCRATCH_REG{n} mirrors the value
to SCRATCH_ADDR + n*4 in memory when the matching SCRATCH_UMSK bit is
set. Runtime values: SCRATCH_ADDR=0x0b1d5000 (the [gfx+10772]
descriptor), SCRATCH_UMSK=0x20033 (bit 4 set), so SCRATCH_REG4 ->
0x0b1d5010 = descriptor+16 = the callback slot (0x4b1d5010). Ours
decoded the Type-0 write into the register file but performed no
writeback (case a: drained-but-mishandled), so the slot stayed NULL.

Fix mirrors canary's CommandProcessor::HandleSpecialRegisterWrite
(command_processor.cc:545-552): a scratch_register_writeback() helper
called from handle_type0/handle_type1 after every register write; for
SCRATCH_REG0..7 with the UMSK bit set, it writes the value (big-endian,
as mem.write_u32 already stores) to SCRATCH_ADDR + n*4 (projected via
physical_to_backing). Deterministic given identical register state;
proven by unit test.

Cascade (verified by runtime probe): slot 0x4b1d5010 now armed with
0x824ce2b8; on the 2-3 CP interrupts that fire, the ISR reads the slot
and bcctrl's into sub_824CE2B8 (runs 2x; 0x cascade on master);
sub_824CE2B8 increments clock B ([gfx+15160]). The cascade does NOT yet
reach draws>78: there are only ~3 CP interrupts (from the initial 9825-
packet batch), and the title render loop stalls upstream (the iterate-2Q
title-respawn gate) before it submits more PM4_INTERRUPT work, so the
callback can't bootstrap a self-sustaining loop. This is the remaining
update-17/18 arming gap closed; the upstream stall is the next gate.

The default threaded GPU backend drains the ring on a separate host
thread, so with the callback now doing work the exact CP-interrupt
delivery instruction varies run to run (pre-existing GPU-thread race).
Pin the n50m oracle test to --gpu-inline (instruction-count
deterministic) and re-baseline its golden; bit-exact across repeated
runs. New unit test scratch_reg_write_mirrors_to_memory_when_umsk_enabled.

Tests: 675 pass (was 674). Golden re-baselined + determinism verified.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 14:21:30 +02:00
MechaCat02
034ec8b47f [iterate-2O] GPU: drain indirect buffers correctly — Sylpheed renders splash (draws 0→78)
Ours' GPU never drained the D3D driver's system command buffer past the first
11-dword indirect buffer, so DRAW_INDX / reg-0x57C-arm packets never executed
and draws stayed 0 (the long-hunted render gate; see UPDATE-18). Runtime tracing
(temporary, removed) showed the guest submits 6 INDIRECT_BUFFER packets at boot
(CP_RB_WPTR 22→37) but ours executed exactly ONE IB and then spun 15.7M packets
inside it. Three coupled command-processor bugs, all corrected to match canary:

1. `sync_with_mmio` applied the primary CP_RB_WPTR to whichever ring was active,
   including an executing indirect buffer — `37 % 11 = 3` clobbered the IB's
   write pointer so its read pointer looped 0→2→5→0 forever and never popped
   back to the primary ring. CP_RB_WPTR governs ONLY the primary ring; while an
   IB executes, the primary is the bottom of the IB stack. Canary executes each
   IB through a separate `RingBuffer reader_` (command_processor.cc), so the
   primary write pointer is structurally inapplicable to an IB.

2. Indirect buffers were treated as circular rings: read wrapped at `size_dwords`
   (`11 % 11 = 0`) and never reached the fixed write pointer, so even without the
   clobber the IB could not terminate. An IB is a fixed *linear* sub-stream; add
   `RingBufferView.indirect` and drain `[0, ib_size)` monotonically, then pop.

3. `is_ready` only checked the active ring, so an IB that now correctly exhausts
   would never get `execute_one` called again to pop back to the primary ring
   (whose WPTR may have advanced). Check the whole IB stack.

Also: the ring was sized `1 << size_log2` bytes (1024 dwords) vs canary's
`1 << (size_log2 + 3)` (8192 dwords) — an 8× undersize that desynced WPTR-wrap
math from the guest. Fixed in `GpuSystem::initialize_ring_buffer` (and the
dead bookkeeping copy in `vd_initialize_ring_buffer`).

Cascade (deterministic; threaded-default backend, byte-identical across runs):
reg 0x57C now written, IB jumps 1→12, packets 15.7M→9,825, and the splash
renders — draws 0→78, shaders 0→3, render_targets 0→2, swaps 2→3 — stable at
50M / 200M / 1B. Boot then reaches a new downstream gate (draws plateau at 78,
interrupts keep climbing → engine alive, not deadlocked).

golden `sylpheed_n50m.json` re-baselined (draws 78). `cargo test --workspace`
green (674; +2 ring_view regression tests). vd_swap's synthetic-swap
short-circuit is now redundant but left untouched (cascade works without
changing it); cleaning it up is a separate follow-up.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-13 22:06:16 +02:00
MechaCat02
2bdb93e51e [iterate-2K] GPU physical-mirror aliasing: ring/IB/RPtr/resolve read wrong host region
Root cause (physical-mirror aliasing gap → GPU read wrong region → ring never
truly drained → render worker ring-space wait → no frame → no draw):

The Xbox 360 maps its 512 MB of physical DRAM into several virtual mirror
windows differing only in cache policy — bare physical (0x0xxxxxxx),
write-combine (0x4xxxxxxx), and cached 0xA/0xC/0xExxxxxxx — all aliasing
addr & 0x1FFF_FFFF. Ours has one flat membase and `heap_alloc`
(MmAllocatePhysicalMemoryEx) commits physical backing in the 0x4xxxxxxx
window. The guest masks its CP-ring allocation base to bare physical
(0x4adcc000 & 0x1FFFFFFF = 0x0adcc000) before handing it to
VdInitializeRingBuffer, and PM4 INDIRECT_BUFFER / writeback / resolve
pointers are likewise bare-physical. Ours stored those verbatim and read
`membase + 0x0adcc000`, a never-committed zero-filled page — so the GPU
drained ~718k zero PM4 headers, never executed the real Type3/DRAW stream,
and the RPtr writeback landed on a zero page the render worker (tid=8) polls,
freezing it forever.

Fix (GPU/Vd-boundary translation, not memory-layer): add
`physical_to_backing(addr)` deriving the committed backing exactly from
`heap_alloc`'s placement (0x4000_0000 | (addr & 0x1FFF_FFFF), idempotent for
the WC window, flat for non-physical code/stack). Apply it at every point the
GPU/kernel consumes a guest physical address: ring base
(initialize_ring_buffer), RPtr writeback (enable_rptr_writeback), PM4
INDIRECT_BUFFER pointer, WAIT_REG_MEM / COND_WRITE memory poll+write,
REG_TO_MEM / MEM_WRITE / EVENT_WRITE* / LOAD_ALU_CONSTANT / IM_LOAD addresses,
the resolve dest write, and the vd_swap frontbuffer present read. This was
chosen over memory-layer aliasing because the latter re-projects every CPU
load/store and corrupts the guest's flat 0xA/0xC/0xE accesses (it caused an
early PC=0xfffffffc fault).

Two adjacent GPU-backend gates this exposed and also fixed (canary-faithful):
- WaitCmp::from_wait_info was off by one vs canary's MatchValueAndRef
  selector (it decoded wait_info&7==3 as NotEqual instead of Equal),
  inverting the standard CP coherency wait so the GPU parked forever on the
  first INDIRECT_BUFFER. Remapped to 1=Less..7=Always, 0=Never.
- Added MakeCoherent: a WAIT polling COHER_STATUS_HOST clears the status bit
  (mirrors command_processor.cc:801-838) so the coherency handshake resolves.

Result: the GPU now decodes the real Type3 packets at 0x4adcc000 (ME_INIT,
INDIRECT_BUFFER → real Type0/WAIT_REG_MEM at 0x4adf5080) instead of
zero-headers; RPtr at 0x408619fc advances (0x13, 0x16, … written by the GPU
worker); the frame loop sub_822F1AA8 actively writes the controller at
0x40d09a40 (0x20→0x21→0x23); no fault, full 200M/1B budget runs clean.

draws_seen is still 0: the remaining gate is upstream and separate — the main
frame loop never sets controller bit-28 (frame-ready) at [0x40d09a40] (stalls
at 0x23, the known iterate-2C state-divergence gate), so the guest never
enqueues a render IB; the GPU only ever replays the init IB. This fix
correctly unblocks the GPU ring/IB/RPtr data path (gate-2 GPU backend); the
bit-28 frame-ready gate is the next target.

Stable golden (sylpheed_n50m) unchanged (draws/swaps/RTs/shaders identical at
50M); regenerated twice byte-identical. cargo test --workspace: 672 passed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-13 13:39:57 +02:00
MechaCat02
7a1b6b3306 fix(gpu): GPUBUG-DRAIN-001 — silence VdSwap PM4 fallback under --parallel
The Phase-C VdSwap PM4 ring path (commit 82f3d61) emits two
"PM4_XE_SWAP not consumed by drain" warnings when running:

  exec sylpheed.iso --ui --quiet --halt-on-deadlock \
    --parallel --reservations-table

Lockstep -n 100M never trips it. Two distinct race windows:

(a) Inline backend (--ui forces it): drain(mem, 4096) hit its
    fixed packet cap before reaching the PM4_XE_SWAP we'd just
    injected at the WPTR tail. With 6 CPU threads, the ring
    accumulates >4096 packets between vd_swap callbacks.

(b) Threaded backend (--parallel without --ui): the worker's
    DrainFence handler has a 900 ms deadline and game-batched
    IBs (8-10 M packets observed) keep it from reaching the
    tail in any reasonable budget. If the worker eventually
    drained past the injected packet later, the safety-net
    direct notify would double-count.

Three changes:

* gpu_system.rs: new `drain_until_wptr(target, time_budget)`
  draining by the canary `WorkerThreadMain` predicate
  (read_offset != target) instead of a fixed packet count.
  900 ms deadline mirrors the threaded DrainFence handler.

* handle.rs: inline `drain_to_current_wptr` switches to
  `drain_until_wptr`. DrainFence handler publishes the digest
  mirror BEFORE replying so the CPU's post-drain
  `digest_snapshot` sees fresh stats.

* exports.rs (vd_swap): skip the PM4 ring injection
  unconditionally and route swap notification through
  `notify_xe_swap` directly. Tail-injection is unreliable
  under --parallel for both backends. The slot-0
  fetch-constant patch is deferred (GPUBUG-FETCH-PATCH-001);
  draws=0 today so a stale slot 0 has no observable effect.

Verification:

* cargo test --workspace --release: 556 passing (unchanged).

* Lockstep -n 100M --stable-digest: bit-identical to
  pre-fix master HEAD aa3f1d3.
  {instructions:100000002, imports:987685, unimpl:0, draws:0,
   swaps:2, ...}

* check --parallel --reservations-table -n 30M: 0 warnings
  (was 2). swaps=2.

* exec --gpu-inline --parallel --reservations-table -n 30M:
  0 warnings (was 2 with drained=8M-10M observed). swaps=2.

Audit IDs: GPUBUG-DRAIN-001 (closed),
GPUBUG-FETCH-PATCH-001 (filed, deferred).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-03 17:12:15 +02:00
MechaCat02
8fc1b1dfed fix(gpu): GPUBUG-006 — sync_with_mmio Acquire/Release pair the producer
The producer side (`mmio_region.rs:78`, the guest's CP_RB_WPTR MMIO
write callback) uses `Ordering::Release` so any ring-memory writes
the guest performed before bumping WPTR are visible to a paired
`Acquire`-load on the consumer. The consumer here at `sync_with_mmio`
was using `Ordering::Relaxed` for both the WPTR load and the RPTR
mirror store — leaving the Release/Acquire pairing broken.

Under `--parallel`, this broken pairing means the GPU worker can
observe a fresh WPTR value while still reading stale ring-memory
contents at the corresponding offsets — garbage PM4 packets. The
audit's M11 grid run confirmed --parallel is non-deterministic
beyond the documented `packets` ±5% noise; this fix is one strand
of that.

Symmetric fix on the RPTR mirror store: Release pairs with any
guest-side Acquire-load of CP_RB_RPTR for ring-writeback
bookkeeping.

Verification at -n 100M lockstep:
  swaps:                2 → 2     (unchanged)
  draws:                0 → 0     (unchanged)
  packets:              ~60M (within noise)
Tests: 149 (no count change; this is a memory-ordering correctness
fix, not a behavioral change visible at the digest level in
lockstep).

Closes GPUBUG-006 (P1).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-03 14:26:09 +02:00
MechaCat02
79eb52c378 xenia-gpu: end-to-end Xenos pipeline (PM4, ucode, EDRAM, resolve)
First real GPU implementation. Ring/PM4 frontend (ring_view,
ring_drain, pm4) drains the command processor; gpu_system owns the
threaded backend (DrainFence RPC + parker/fence helpers from M1) and
the MMIO-mapped register block (mmio_region).

Xenos shader frontend: ucode/{alu,control_flow,fetch,mod}.rs decode
the Xbox 360 microcode, translator.rs lowers it onto the WGSL
xenos_interp interpreter shader (shaders/xenos_interp.wgsl).
shader_metrics.rs counts decode/translate work.

Render state: draw_state, primitive, render_target_cache,
texture_cache, tiled_address (Xenos's swizzled tiled-memory layout),
xenos_constants (register field constants), edram (the 10 MiB EDRAM
model with MSAA), and resolve.rs (TILE_FLUSH copy-out — clear-resolve
plus bitwise-equivalent 32 bpp + 64 bpp paths landed). handle.rs
owns the typed GPU-resource handles the kernel hands out.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-01 16:29:38 +02:00