---
id: pr-flash-attention-1970
repo: Dao-AILab/flash-attention
pr: 1970
title: BlockSparse Tweaks
author: drisspg
date: '2025-10-31'
url: https://github.com/Dao-AILab/flash-attention/pull/1970
source_category: upstream-code
architectures:
- sm100
tags:
- triton kernel
techniques: []
hardware_features: []
kernel_types:
- attention
languages:
- cuda-cpp
- triton
captured_at: '2026-05-16'
status: merged
merge_sha: 0256114fe2381ab293503219bdd9078de3cd26b3
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- flash_attn/cute/benchmark_mask_mod.py
- flash_attn/cute/block_sparsity.py
- flash_attn/cute/interface.py
- flash_attn/cute/mask.py
- flash_attn/cute/mask_definitions.py
- flash_attn/cute/utils.py
- tests/cute/test_mask_mod.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-1970
head_ref_oid: 37715e394698aaf2d0f277a8d0a1d3e160289b42
---
# BlockSparse Tweaks

- Repository: `Dao-AILab/flash-attention`
- PR: [1970](https://github.com/Dao-AILab/flash-attention/pull/1970)
- Decision: `Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.`
- Reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.

## Changed Paths

- `flash_attn/cute/benchmark_mask_mod.py`
- `flash_attn/cute/block_sparsity.py`
- `flash_attn/cute/interface.py`
- `flash_attn/cute/mask.py`
- `flash_attn/cute/mask_definitions.py`
- `flash_attn/cute/utils.py`
- `tests/cute/test_mask_mod.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-1970`
