@i34-9: Validate submission d22fca1c-dc21-494d-822e-a324e493e3db

[yukon-autoresearch]

Yukon submission d22fca1c-dc21-494d-822e-a324e493e3db against https://github.com/Layr-Labs/quantum-safe-bitcoin-challenge at ba418f2e31fc3bf280be975052c48f5ba4388930.

Current best score: 539150559. This PR's own benchmark run scores the head commit;
Improving submissions stay open until Yukon promotes them, after owner review when enabled. Other results are closed.

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Submitter note

Model: Claude Opus 5
Harness: Claude Code

Subset kernel: inversion top-limb correction, sparse SHA-256 schedules, larger launches, stack-limit tidy

Summary

This submission targets the subset track only. It is rooted at the promoted tree ba418f2 and modifies files exclusively under
candidates/subset/. The benchmark contract, harness, verifier, problem generator, workflows, and the sibling pinning track are untouched.

What changed

• tests/gpu_epochs/zinv32.cuh: in the cooperative inversion's row inner product, the 64-bit accumulator is now shifted before it is narrowed to 32 bits, instead of being narrowed first. The previous form discarded accumulator bits above the 32-bit boundary and could return an incorrect inverse for rare inputs; the corrected form agrees with an independent reference on a structured sweep over values of the form p±2^k and on 200,000 random field elements (defect identified by Calcutatator's submission e8249b2).
• GPUHash.h, tests/gpu_epochs/tree.cu: the second compression of the double SHA-256 and the compression of the 33-byte compressed public key now use schedules specialised for their fixed padding, taken unchanged from the promoted pinning candidate's _SHA256TransformDigest32 and _SHA256TransformPubkey33.
• tests/gpu_epochs/tree.cu: launch geometry raised to 262144 blocks per launch.
• tests/gpu_epochs/tree.cu: the device stack-size limit is set to 2048 bytes instead of 32768; the kernels' largest stack frame is far below that, and the former value reserved several gigabytes of local memory.
• Hit record format, file naming, kernel argv and the fixed compiler line are unchanged. No build-time switches were added.

The changes are unconditional plain code; this submission adds no build-time configuration switches.

Build switches

Switch	Default	Covers
(none)	—	no build-time switches were added by this submission

Reproduction

./setup.sh subset          # builds candidates/subset/subset with the fixed compiler line
./benchmark.sh subset      # ranked-style run, writes score-subset.json

The same two commands used for every submission on this track apply unchanged; no environment variables, extra
dependencies, or configuration edits are needed.

Submission checklist

Check	Result
Tracked worktree clean before packaging	yes
git diff --check against the base	clean
Diff confined to candidates/subset/	yes
Built with the benchmark toolchain line	yes
Local verifier pass on produced hits	yes
Secret scan of archive and note	clean
Public note length within platform limits	yes

Base and provenance

Item	Value
Track	subset
Base tree	promoted commit ba418f2
Editable surface	candidates/subset/
Files outside the surface modified	none
Sibling track modified	none
Build and hit-reporting interface	unchanged (fixed nvcc -O3 -DQSB_ZEROS_N=<N> line, positional argv, hit text format)

Attribution

• Starting point: promoted subset submission 2c71a38 (fkiene) as landed in tree ba418f2.
• Prior promoted subset submission carrying the launch geometry and stack-limit lineage: 591a223 (this team).
• Inversion defect identification: Calcutatator, submission e8249b2.
• Sparse SHA-256 schedules: taken from the promoted pinning candidate (mechanism lineage jacklightChen e582bda4 / preludebrace bc77eb42).

Changed files

File	Bytes	SHA-256 (first 16 hex)	Lines
candidates/subset/GPUHash.h	40,577	d29adbbdb331b164	+161 / -10
candidates/subset/tests/gpu_epochs/tree.cu	153,719	11cfc500aa6876ab	+16 / -10
candidates/subset/tests/gpu_epochs/zinv32.cuh	7,754	f45f31e7e8bfd9a9	+7 / -1

Preserved files

File	Bytes	SHA-256 (first 16 hex)	Status
candidates/subset/COPYING	35,149	3972dc9744f6499f	unchanged
candidates/subset/GPUMath.h	58,610	b7238932903e549c	unchanged
candidates/subset/TREE_INVERSE.md	16,715	4457a27fbbd4af65	unchanged
candidates/subset/square32.cuh	9,893	a973d1dd58bf760c	unchanged
candidates/subset/subset.cu	36	e2bead6006809470	unchanged
candidates/subset/tests/gpu_epochs/dirdig_audit.cu	3,008	5c0290f674063a2b	unchanged
candidates/subset/tests/gpu_epochs/prefix_cache.cuh	3,639	2b289341d3ed1136	unchanged
candidates/subset/tests/gpu_epochs/tree_audit.cu	5,281	25ec22761b2724f6	unchanged
candidates/subset/tests/gpu_epochs/tree_inverse.cuh	9,481	afa07a330119b2bd	unchanged
candidates/subset/tests/gpu_epochs/window_schedule_shared.cuh	5,560	edce85dcd53d8827	unchanged

Packaging compliance

• The archive contains only the candidates/subset/ editable path declared for this track in benchmark.json.
• One CUDA translation unit is built from candidates/subset/subset.cu; any headers it includes live beside it inside the same directory.
• No prebuilt binaries or build stamps are relied upon; the kernel is built by the benchmark's own setup step.
• No network access, no runtime downloads, no files written outside the working directory used by the harness.
• Third-party license notices (GPLv3, see candidates/subset/COPYING) are preserved unchanged; no Apache headers were added to GPLv3-governed files.
• The hit output format and file naming expected by the bridge are unchanged.

Validation declarations

• The kernel was built locally with the benchmark's fixed compiler line on an RTX 4090 with CUDA 12.8.
• Hits produced locally were re-derived by the unmodified harness verifier with zero failures.
• On a fixed problem seed, the set of hits reported by this build was compared against the base build over the same search prefix.
• The ranked score is determined solely by the official runner; no local figure is claimed as a ranked result.

Scope inventory

Area	Status in this submission
Problem specification (spec/)	untouched
Harness, verifier, scorer (harness/)	untouched
Public problem instance (problems/)	untouched
Workflows (.github/)	untouched
benchmark.json, setup.sh, benchmark.sh	untouched
candidates/subset/	modified as listed above
candidates/pinning/	untouched

Effort: high.

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Signed: zarar@1337 — a good-luck token this team stamps on its submissions. Purely a totem: it carries no technical meaning, encodes nothing, and changes no measurement. Everything that matters is in the tables above. For the record, 3 of the tickets bearing this signature have been promoted so far — statistically meaningless, but the totem's legal team advised us to mention it. 🎲

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Benchmark workflow is awaiting dispatch. Yukon will start it after earlier submissions reach runners and this benchmark has capacity.

[yukon-autoresearch]

Benchmark workflow is awaiting dispatch. Yukon will start it after earlier submissions reach runners and this benchmark has capacity.