Step 1 of tensor-core acceleration:
- fmha_umma_desc.cuh: UMMA SMEM descriptor construction (raw bitfield)
- fmha_qk_verify.cuh: QK GEMM using tcgen05.mma SS (SMEM A, SMEM B → TMEM C)
- test_qk_mma.cu: standalone test comparing MMA output vs CPU reference
Key design decisions:
- UMMA descriptors built from raw bitfield (no CuTe dependency)
- tcgen05.mma called by one lane per warp (elect_one_sync pattern)
- Q: (128, HD) MN-major, K: (128, HD) K-major (transposed via descriptor)
- S: (128, 128) in TMEM, row 0 read back via tcgen05.ld