swapab_cutedsl_megakernel

Updating the SM120 swap-AB CuTeDSL MegaMoE kernel src

Layout

kernel_src/sm120/swapab_cutedsl_megakernel/
├── src/                    ← VERBATIM kernel-team drop; NEVER edit or add files here
│   ├── common/
│   ├── src/                ← CuTeDSL core src (bootstrap, sym_buffer, token_comm, …)
│   ├── moe_sm120_mxfp8_swapab/  ← the SM120 MXFP8 swap-AB kernel
│   ├── moe_mxfp8_glu/      ← generic MXFP8 torch reference (+ its runner helpers)
│   └── moe_nvfp4_swapab/   ← import dependency of moe_mxfp8_glu's reference
├── __init__.py             ← public API for moe_ep; talks ONLY to shim/ (our code)
├── shim/                   ← thin adapters over src/ (our code) — ALL adaptation here
│   ├── _paths.py           ← adds sibling src/ to sys.path; sibling-tree guard
│   ├── comm.py             ← dist bootstrap, sym heap, compile state,
│   │                          zero_local_counter_regions (SM120 pre-launch contract)
│   ├── mxfp8.py            ← SM120 MXFP8 frontend + symm-buffer/launch wrappers
│   └── kernel_helpers.py   ← SINGLE (all-lazy) re-export point for raw-kernel
│                              helpers/constants/reference (drop-audit point)
├── VENDOR.md               ← provenance + sync state of the current src/ drop
└── SKILL.md                ← this file (drop-update workflow)

Core principle: src/ is a verbatim copy of the kernel-team drop — no injected files, no edits. Every adaptation lives in shim/. A new drop is a pure replace of src/; the only work is updating shim/ to whatever the new src/ exposes.

Layer isolation (enforce on every drop — grep before/after): shim/ is the only layer importing src/ packages; FI backends (backends/mega/kernel/sm120/mxfp8_mxfp8_bf16_cutedsl/) import ONLY the package __init__; the tree is process-exclusive with the SM100/SM90 trees (shared top-level module names — shim/_paths.py raises on collision).

When the kernel team drops a new version of src/

1. Replace src/ verbatim with the drop's five kernel packages:

   cd flashinfer/moe_ep/kernel_src/sm120/swapab_cutedsl_megakernel/src
   rm -rf common src moe_sm120_mxfp8_swapab moe_mxfp8_glu moe_nvfp4_swapab
   cp -r <new_drop>/{common,src,moe_sm120_mxfp8_swapab,moe_mxfp8_glu,moe_nvfp4_swapab} .
   

   Do NOT copy repo scaffolding (ci/, tester/, tests/, scripts/, pyproject.toml, dispatch_test.py, README.md, core.python.*). Update VENDOR.md (commit SHA, date, pending local diffs).