---
id: pr-cccl-cub-8639
repo: NVIDIA/cccl
pr: 8639
title: Segmented scan multisegment part 1
author: oleksandr-pavlyk
date: '2026-04-28'
url: https://github.com/NVIDIA/cccl/pull/8639
source_category: upstream-code
architectures:
- sm100
tags:
- benchmark kernel
- block
- cooperative-groups
- cuda kernel
- scan
- warp
techniques:
- warp-specialization
hardware_features: []
kernel_types:
- scan
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 8dd2e304a6c456ff75b2b698748c15a1ff70a1dc
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- cub/benchmarks/bench/segmented_scan/base.cuh
- cub/benchmarks/bench/segmented_scan/custom.cu
- cub/benchmarks/bench/segmented_scan/sum.cu
- cub/cub/agent/agent_segmented_scan.cuh
- cub/cub/detail/segmented_scan_helpers.cuh
- cub/cub/device/device_segmented_scan.cuh
- cub/cub/device/dispatch/dispatch_segmented_scan.cuh
- cub/cub/device/dispatch/kernels/kernel_segmented_scan.cuh
- cub/cub/device/dispatch/tuning/tuning_segmented_scan.cuh
- cub/test/catch2_test_device_segmented_scan.cu
- cub/test/catch2_test_device_segmented_scan_multi_segment.cu
artifact_dir: evidence/pull-bundles/cccl-cub/gh-8639
head_ref_oid: 53f063a592069f51407334ff30d83270fcaa511f
---
# Segmented scan multisegment part 1

- Repository: `NVIDIA/cccl`
- PR: [8639](https://github.com/NVIDIA/cccl/pull/8639)
- 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

- `cub/benchmarks/bench/segmented_scan/base.cuh`
- `cub/benchmarks/bench/segmented_scan/custom.cu`
- `cub/benchmarks/bench/segmented_scan/sum.cu`
- `cub/cub/agent/agent_segmented_scan.cuh`
- `cub/cub/detail/segmented_scan_helpers.cuh`
- `cub/cub/device/device_segmented_scan.cuh`
- `cub/cub/device/dispatch/dispatch_segmented_scan.cuh`
- `cub/cub/device/dispatch/kernels/kernel_segmented_scan.cuh`
- `cub/cub/device/dispatch/tuning/tuning_segmented_scan.cuh`
- `cub/test/catch2_test_device_segmented_scan.cu`
- `cub/test/catch2_test_device_segmented_scan_multi_segment.cu`

## Evidence Bundle

`evidence/pull-bundles/cccl-cub/gh-8639`
