de21c7a544
The silph title state machine (tid13) blocked on event 0x10a0, never signaled. Root: the event's producer chain runs on the silph worker (entry 0x821C4AD0, our tid14), which was starved. tid14 shares a HW slot with a guest spinlock/ barrier participant (sub_824D1328, entry 0x824D2940) that busy-spins on the db16cyc hint `or r31,r31,r31` (encoding 0x7FFFFB78) at 0x824D140C. Under our round-robin lockstep the spinner consumed its whole block every round and starved the co-located tid14 (only 9 progress hits over 200M instr) — so the producer never reached the event-create/duplicate/signal dance the canary oracle performs (handle F80000E8 set by the submitter F8000044 via a duplicated handle). Fix (canary-faithful): recognize the db16cyc spin hint exactly as canary's InstrEmit_orx does (code 0x7FFFFB78 -> DelayExecution) and surface it as a new StepResult::Yield. The scheduler's yield_current() promotes every Ready peer on the slot past STARVE_LIMIT so begin_slot_visit picks one next round, then they reset and the spinner reclaims the slot — fair alternation, no priority inversion, pure function of slot state (deterministic). Result (lockstep, cache-persist, -n 200M): tid14 progresses past its old stall into a real wait; tid13 advances off 0x10a0 to a new event; hub/submitter re-enter their wait loops. imports 280k->592k, packets 124M->164M, swaps 1->2. draws still 0 (the splash's first draw is a further-upstream gate). Determinism preserved (two cold n50m runs byte-identical). n50m golden re-baselined (imports 90296->339766, swaps 1->2; draws unchanged 0). n2m golden unchanged (db16cyc not reached in first 2M). Tests 670/670. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Sylpheed regression goldens
These JSON files anchor xenia-rs check digest output for Project Sylpheed.
Files
| File | -n | Mode | Captures |
|---|---|---|---|
sylpheed_n2m.json |
2_000_000 | full digest | early boot (swaps=0, no rendering) |
sylpheed_n50m.json |
50_000_000 | stable-digest | first VdSwap pair (swaps=2 post-Phase-A) |
Stable-digest mode
sylpheed_n50m.json is captured with --stable-digest, which omits
timing-sensitive counters: packets (±2–8% lockstep noise from a GPU thread
race), resolves, interrupts_delivered, interrupts_dropped,
texture_decodes. The remaining fields are byte-identical across repeated
lockstep runs at a fixed -n.
sylpheed_n2m.json predates the stable-digest flag and uses full-digest
compare. It still works because at -n 2M the GPU pipeline has not produced any
packets yet — packets=0 is trivially deterministic.
Circularity hazard
Per ORACBUG-001/002/003, these goldens were captured by running the same code
they validate. They detect regression from a known-good snapshot, not
correctness. When a planned fix intentionally moves the digest (e.g. a
shader fix landing draws > 0 for the first time), re-baseline the golden as
a separate commit and reference the audit ID in the message.
Re-baselining
cargo build --release -p xenia-app
target/release/xenia-rs check \
"$SYLPHEED_ISO" \
-n 50000000 \
--stable-digest \
--out crates/xenia-app/tests/golden/sylpheed_n50m.json
Running the goldens
cargo test --release -p xenia-app --test sylpheed_oracles -- --ignored --nocapture
The tests are #[ignore]-gated because each run takes a few seconds, which is
unacceptable in the default cargo test cycle. The ISO path defaults to the
contributor's local ~/RE Project Sylpheed/Project Sylpheed*.iso and can be
overridden via SYLPHEED_ISO=/path/to/sylpheed.iso.
n4b canonical-invocation regression anchor (deferred)
The audit's recommended next sprint also called for a sylpheed_n4b.json
golden capturing the canonical reference invocation
xenia-rs check sylpheed.iso -n 4_000_000_000 --parallel --reservations-table.
This is deferred because:
- The
--parallel --reservations-tablecombination is empirically pathologically slow at -n 100M (>32 min per run per the audit memory). At -n 4B the run cost is many hours, not the single-session-friendly 5–15 min the original plan estimated. - Each phase that intentionally moves rendering counters (C, D, E, F) would need a re-baseline of n4b — a significant time cost compounding over the sprint.
Once the renderer-unblock phases (C+D+E) land and draws > 0 is confirmed at
-n 100M lockstep, an n4b artifact may be captured one-shot and stored under
audit-runs/post-fix/ (not as a test golden) as a manual regression anchor for
the canonical invocation.