---
id: pr-flash-attention-1985
repo: Dao-AILab/flash-attention
pr: 1985
title: '[Cute] Block sparse support Sm100'
author: drisspg
date: '2025-11-18'
url: https://github.com/Dao-AILab/flash-attention/pull/1985
source_category: upstream-code
architectures:
- sm100
- sm90
tags:
- arch_pipeline
- attention_kv
- benchmark_test
- block sparse
- compiler_runtime
- hopper
- softmax
techniques:
- async-copy
- pipeline-stages
hardware_features:
- blackwell
- hopper
- tma
kernel_types:
- attention
- compiler
- runtime
- softmax
languages:
- cute-dsl
captured_at: '2026-05-16'
status: merged
merge_sha: b4555bfc3244a7607ea499158d3ef0b3a9ea2860
inclusion_reason: 'Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.'
changed_paths:
- flash_attn/cute/block_sparse_utils.py
- flash_attn/cute/compute_block_sparsity.py
- flash_attn/cute/flash_bwd_sm100.py
- flash_attn/cute/flash_fwd_sm100.py
- flash_attn/cute/interface.py
- flash_attn/cute/mask.py
- tests/cute/test_mask_mod.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-1985
head_ref_oid: 13948bcec8a06946264e5c8bbf8369a757c4d46c
---
# [Cute] Block sparse support Sm100

- Repository: `Dao-AILab/flash-attention`
- PR: [1985](https://github.com/Dao-AILab/flash-attention/pull/1985)
- Decision: `Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.`
- Reason: Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.

## Changed Paths

- `flash_attn/cute/block_sparse_utils.py`
- `flash_attn/cute/compute_block_sparsity.py`
- `flash_attn/cute/flash_bwd_sm100.py`
- `flash_attn/cute/flash_fwd_sm100.py`
- `flash_attn/cute/interface.py`
- `flash_attn/cute/mask.py`
- `tests/cute/test_mask_mod.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-1985`
