CUB 1.14.0 (NVIDIA HPC SDK 21.9)

[alliepiper]

CUB 1.14.0 is a major release accompanying the NVIDIA HPC SDK 21.9.

This release provides the often-requested merge sort algorithm, ported from the thrust::sort implementation. Merge sort provides more flexibility than the existing radix sort by supporting arbitrary data types and comparators, though radix sorting is still faster for supported inputs. This functionality is provided through the new cub::DeviceMergeSort and cub::BlockMergeSort algorithms.

The namespace wrapping mechanism has been overhauled for 1.14. The existing macros (CUB_NS_PREFIX/CUB_NS_POSTFIX) can now be replaced by a single macro, CUB_WRAPPED_NAMESPACE, which is set to the name of the desired wrapped namespace. Defining a similar THRUST_CUB_WRAPPED_NAMESPACE macro will embed both thrust:: and cub:: symbols in the same external namespace. The prefix/postfix macros are still supported, but now require a new CUB_NS_QUALIFIER macro to be defined, which provides the fully qualified CUB namespace (e.g. ::foo::cub). See cub/util_namespace.cuh for details.

Breaking Changes

• Notify users that CUB_NS_QUALIFIER must be set when using other NS macros #350: When the CUB_NS_[PRE|POST]FIX macros are set, CUB_NS_QUALIFIER must also be defined to the fully qualified CUB namespace (e.g. #define CUB_NS_QUALIFIER ::foo::cub). Note that this is handled automatically when using the new [THRUST_]CUB_WRAPPED_NAMESPACE mechanism.

New Features

• Add CUB block and device merge sort #322: Ported the merge sort algorithm from Thrust; cub::BlockMergeSort and cub::DeviceMergeSort are now available.
• Simplify usage of namespace macros, add thrust compatibility. #326: Simplify the namespace wrapper macros, and detect when Thrust's symbols are in a wrapped namespace.

Bug Fixes

• Put in somewhat hacky fix for out of bounds accesses #160, Fixes Issues #161 and #162 #163, cub::DeviceSpmv: Various fixes and tests #352: Fixed several bugs in cub::DeviceSpmv and added basic tests for this algorithm. Thanks to James Wyles and Seunghwa Kang for their contributions.
• Small fixes for CachingDeviceAllocator #328: Fixed error handling bug and incorrect debugging output in cub::CachingDeviceAllocator. Thanks to Felix Kallenborn for this contribution.
• Fix clang compile error #335: Fixed a compile error affecting clang and NVRTC. Thanks to Jiading Guo for this contribution.
• Update histogram documentation. #351: Fixed some errors in the cub::DeviceHistogram documentation.

Enhancements

• Docs update: how to use dynamic shared mem with block reduce #348: Add an example that demonstrates how to use dynamic shared memory with a CUB block algorithm. Thanks to Matthias Jouanneaux for this contribution.

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This discussion was created from the release CUB 1.14.0 (NVIDIA HPC SDK 21.9).