- Rehashed ten retained contract, parity, timing, and NCU artifacts; all matched
`benchmarks/reference_inventory.json`.
- Imported Q/K preparation, K smoothing, INT8 quantization, QK traversal,
online-softmax, FP8 V/P, two-level PV accumulation, final conversion, and
ragged-tail contracts into `NUMERICAL_CONTRACT.md`.
- Recorded missing production binary/checkpoint hashes and missing standalone
canonical input tensors as blockers rather than fabricating provenance.
- Did not execute inference, modify dispatch, or touch the production service.
Decision: Phase 0 is verified as an imported specification. No kernel work is
authorized until Phase 1 selects a structural state-ownership architecture.
## Closed Prior Work
| Work | Result | Preservation / reopening rule |
| --- | --- | --- |
| P0 register caps | Three-CTA threshold at 168 registers caused catastrophic spills; no gain | Timing/JSON/NCU retained; exact candidate source missing and must not be claimed reproducible |
| P0 scope/lifetime narrowing | Fewer spills, approximately `0.06%` gain | Reopen only with structural ownership change |
| P0 score aliasing | Approximately `0.01%`, noise | Do not repeat unchanged |
| P0 early K prefetch | Approximately `0.30%` slower | Reopen only with a different producer/consumer pipeline |
| P0 softmax interleaving | Neutral/slower | Do not repeat unchanged |
| P0 padded V shared memory | Same excessive wavefronts, no gain | Reopen only if staging instructions/dataflow change |
| P1 entry fusion | `20.9-23.4%` isolated; only `0.535-0.863%` complete-block | Reuse partial implementation only inside an owned attention pipeline |
| P2 direct V preparation | `39.48%`, `4.17 ms`; only `0.909%` of block | Reuse partial implementation only inside an owned attention pipeline |
| P3 temporal pairing | Exact/sanitizer-clean; approximately `0.10%`; private state remained live | Complete patch and launcher retained; new work must transfer/partition ownership |
| Hopper WGMMA retarget | CUDA 13 rejects WGMMA for `sm_121a` | Reopen only with changed ISA/toolchain support |
| SM121 UMMA INT8 QK | Public SM120/121 Blackwell MMA path does not expose a Sage-compatible UMMA INT8 operation | Retain supported INT8 `mma.sync` unless capability changes |
P1/P2 source is partial and mixed in
`research/shared_cuda_experimental_worktree/`. P3 source and launcher are
complete under `research/sage2_temporal_pair/`. Exact P0 variant patches are
unrecoverable; historical commands and environments must not be invented.
