---
id: pr-cccl-cub-8766
repo: NVIDIA/cccl
pr: 8766
title: '[cudax] Implement `composite_mapping` for groups'
author: davebayer
date: '2026-05-05'
url: https://github.com/NVIDIA/cccl/pull/8766
source_category: upstream-code
architectures:
- sm100
tags:
- warp
techniques:
- warp-specialization
hardware_features: []
kernel_types: []
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: d7d70795853cba30ea57418757171f48675b4eed
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- cudax/include/cuda/experimental/__group/fwd.cuh
- cudax/include/cuda/experimental/__group/mapping/composite_mapping.cuh
- cudax/include/cuda/experimental/group.cuh
- cudax/test/CMakeLists.txt
- cudax/test/group/mapping/composite_mapping.cu
artifact_dir: evidence/pull-bundles/cccl-cub/gh-8766
head_ref_oid: 6e9f26e738d24ccab79759250c7bf8aa1abaf4a5
---
# [cudax] Implement `composite_mapping` for groups

- Repository: `NVIDIA/cccl`
- PR: [8766](https://github.com/NVIDIA/cccl/pull/8766)
- 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

- `cudax/include/cuda/experimental/__group/fwd.cuh`
- `cudax/include/cuda/experimental/__group/mapping/composite_mapping.cuh`
- `cudax/include/cuda/experimental/group.cuh`
- `cudax/test/CMakeLists.txt`
- `cudax/test/group/mapping/composite_mapping.cu`

## Evidence Bundle

`evidence/pull-bundles/cccl-cub/gh-8766`
