update of dr::shp::sort() (#1614)

Author: lslusarczyk

.clang-format

@@ -1,6 +1,6 @@
 BasedOnStyle: LLVM
 
-Standard: c++17
+Standard: c++20
 
 IndentWidth: 4
 ColumnLimit: 120

CODE_OF_CONDUCT.md

@@ -0,0 +1,128 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+We as members, contributors, and leaders pledge to make participation in our
+community a harassment-free experience for everyone, regardless of age, body
+size, visible or invisible disability, ethnicity, sex characteristics, gender
+identity and expression, level of experience, education, socio-economic status,
+nationality, personal appearance, race, religion, or sexual identity
+and orientation.
+
+We pledge to act and interact in ways that contribute to an open, welcoming,
+diverse, inclusive, and healthy community.
+
+## Our Standards
+
+Examples of behavior that contributes to a positive environment for our
+community include:
+
+* Demonstrating empathy and kindness toward other people
+* Being respectful of differing opinions, viewpoints, and experiences
+* Giving and gracefully accepting constructive feedback
+* Accepting responsibility and apologizing to those affected by our mistakes,
+  and learning from the experience
+* Focusing on what is best not just for us as individuals, but for the
+  overall community
+
+Examples of unacceptable behavior include:
+
+* The use of sexualized language or imagery, and sexual attention or
+  advances of any kind
+* Trolling, insulting or derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or email
+  address, without their explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Enforcement Responsibilities
+
+Community leaders are responsible for clarifying and enforcing our standards of
+acceptable behavior and will take appropriate and fair corrective action in
+response to any behavior that they deem inappropriate, threatening, offensive,
+or harmful.
+
+Community leaders have the right and responsibility to remove, edit, or reject
+comments, commits, code, wiki edits, issues, and other contributions that are
+not aligned to this Code of Conduct, and will communicate reasons for moderation
+decisions when appropriate.
+
+## Scope
+
+This Code of Conduct applies within all community spaces, and also applies when
+an individual is officially representing the community in public spaces.
+Examples of representing our community include using an official e-mail address,
+posting via an official social media account, or acting as an appointed
+representative at an online or offline event.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported to the community leaders responsible for enforcement at
+oneDPLCodeOfConduct@intel.com.
+All complaints will be reviewed and investigated promptly and fairly.
+
+All community leaders are obligated to respect the privacy and security of the
+reporter of any incident.
+
+## Enforcement Guidelines
+
+Community leaders will follow these Community Impact Guidelines in determining
+the consequences for any action they deem in violation of this Code of Conduct:
+
+### 1. Correction
+
+**Community Impact**: Use of inappropriate language or other behavior deemed
+unprofessional or unwelcome in the community.
+
+**Consequence**: A private, written warning from community leaders, providing
+clarity around the nature of the violation and an explanation of why the
+behavior was inappropriate. A public apology may be requested.
+
+### 2. Warning
+
+**Community Impact**: A violation through a single incident or series
+of actions.
+
+**Consequence**: A warning with consequences for continued behavior. No
+interaction with the people involved, including unsolicited interaction with
+those enforcing the Code of Conduct, for a specified period of time. This
+includes avoiding interactions in community spaces as well as external channels
+like social media. Violating these terms may lead to a temporary or
+permanent ban.
+
+### 3. Temporary Ban
+
+**Community Impact**: A serious violation of community standards, including
+sustained inappropriate behavior.
+
+**Consequence**: A temporary ban from any sort of interaction or public
+communication with the community for a specified period of time. No public or
+private interaction with the people involved, including unsolicited interaction
+with those enforcing the Code of Conduct, is allowed during this period.
+Violating these terms may lead to a permanent ban.
+
+### 4. Permanent Ban
+
+**Community Impact**: Demonstrating a pattern of violation of community
+standards, including sustained inappropriate behavior,  harassment of an
+individual, or aggression toward or disparagement of classes of individuals.
+
+**Consequence**: A permanent ban from any sort of public interaction within
+the community.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 2.0, available at
+https://www.contributor-covenant.org/version/2/0/code_of_conduct.html.
+
+Community Impact Guidelines were inspired by [Mozilla's code of conduct
+enforcement ladder](https://github.com/mozilla/diversity).
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see the FAQ at
+https://www.contributor-covenant.org/faq. Translations are available at
+https://www.contributor-covenant.org/translations.

documentation/library_guide/parallel_api/iterators.rst

@@ -78,9 +78,11 @@ header.  All iterators are implemented in the ``oneapi::dpl`` namespace.
   The ``transform_iterator`` class provides the following constructors:
 
   * ``transform_iterator()``: instantiates the iterator using a default constructed base iterator and unary functor.
-  This constructor participates in overload resolution only if the base iterator and unary functor are both default constructible.
+    This constructor participates in overload resolution only if the base iterator and unary functor are both default constructible.
+  
   * ``transform_iterator(iter)``: instantiates the iterator using the base iterator provided and a default constructed
-  unary functor. This constructor participates in overload resolution only if the unary functor is default constructible.
+    unary functor. This constructor participates in overload resolution only if the unary functor is default constructible.
+  
   * ``transform_iterator(iter, func)``: instantiates the iterator using the base iterator and unary functor provided.
 
   To simplify the construction of the iterator, ``oneapi::dpl::make_transform_iterator`` is provided. The

documentation/release_notes.rst

@@ -8,6 +8,90 @@ The Intel® oneAPI DPC++ Library (oneDPL) accompanies the Intel® oneAPI DPC++/C
 and provides high-productivity APIs aimed to minimize programming efforts of C++ developers
 creating efficient heterogeneous applications.
 
+New in 2022.6.0
+===============
+News
+------------
+- `oneAPI DPC++ Library Manual Migration Guide`_ to simplify the migration of Thrust* and CUB* APIs from CUDA*. 
+- ``radix_sort`` and ``radix_sort_by_key`` kernel templates were moved into
+  ``oneapi::dpl::experimental::kt::gpu::esimd`` namespace. The former ``oneapi::dpl::experimental::kt::esimd``
+  namespace is deprecated and will be removed in a future release.
+- The ``for_loop``, ``for_loop_strided``, ``for_loop_n``,  ``for_loop_n_strided`` algorithms
+  in `namespace oneapi::dpl::experimental` are enforced to fail with device execution policies.
+
+New Features
+------------
+- Added experimental ``inclusive_scan`` kernel template algorithm residing in
+  the ``oneapi::dpl::experimental::kt::gpu`` namespace. 
+- ``radix_sort`` and ``radix_sort_by_key`` kernel templates are extended with overloads for out-of-place sorting.
+  These overloads preserve the input sequence and sort data into the user provided output sequence.
+- Improved performance of the ``reduce``, ``min_element``, ``max_element``, ``minmax_element``, ``is_partitioned``,
+  ``lexicographical_compare``, ``binary_search``, ``lower_bound``, and ``upper_bound`` algorithms with device policies.
+-  ``sort``, ``stable_sort``, ``sort_by_key`` algorithms now use Radix sort [#fnote1]_
+   for sorting ``sycl::half`` elements compared with ``std::less`` or ``std::greater``.
+
+Fixed Issues
+------------
+- Fixed compilation errors when using ``reduce``, ``min_element``, ``max_element``, ``minmax_element``,
+  ``is_partitioned``, and ``lexicographical_compare`` with Intel oneAPI DPC++/C++ compiler 2023.0 and earlier.
+- Fixed possible data races in the following algorithms used with device execution policies:
+  ``remove_if``, ``unique``, ``inplace_merge``, ``stable_partition``, ``partial_sort_copy``, ``rotate``.
+- Fixed excessive copying of data in ``std::vector`` allocated with a USM allocator for standard library
+  implementations which have allocator information in the ``std::vector::iterator`` type.
+- Fixed an issue where checking ``std::is_default_constructible`` for ``transform_iterator`` with a functor
+  that is not default-constructible could cause a build error or an incorrect result.
+- Fixed handling of `sycl device copyable`_ for internal and public oneDPL types.
+- Fixed handling of ``std::reverse_iterator`` as input to oneDPL algorithms using a device policy.
+- Fixed ``set_intersection`` to always copy from the first input sequence to the output,
+  where previously some calls would copy from the second input sequence.
+- Fixed compilation errors when using ``oneapi::dpl::zip_iterator`` with the oneTBB backend and C++20.
+
+Known Issues and Limitations
+----------------------------
+New in This Release
+^^^^^^^^^^^^^^^^^^^
+- ``histogram`` algorithm requires the output value type to be an integral type no larger than 4 bytes
+  when used with an FPGA policy.
+
+Existing Issues
+^^^^^^^^^^^^^^^
+See oneDPL Guide for other `restrictions and known limitations`_.
+
+- When compiled with ``-fsycl-pstl-offload`` option of Intel oneAPI DPC++/C++ compiler and with
+  ``libstdc++`` version 8 or ``libc++``, ``oneapi::dpl::execution::par_unseq`` offloads
+  standard parallel algorithms to the SYCL device similarly to ``std::execution::par_unseq``
+  in accordance with the ``-fsycl-pstl-offload`` option value.
+- When using the dpl modulefile to initialize the user's environment and compiling with ``-fsycl-pstl-offload``
+  option of Intel® oneAPI DPC++/C++ compiler, a linking issue or program crash may be encountered due to the directory
+  containing libpstloffload.so not being included in the search path. Use the env/vars.sh to configure the working
+  environment to avoid the issue.
+- Compilation issues may be encountered when passing zip iterators to ``exclusive_scan_by_segment`` on Windows. 
+- For ``transform_exclusive_scan`` and ``exclusive_scan`` to run in-place (that is, with the same data
+  used for both input and destination) and with an execution policy of ``unseq`` or ``par_unseq``, 
+  it is required that the provided input and destination iterators are equality comparable.
+  Furthermore, the equality comparison of the input and destination iterator must evaluate to true.
+  If these conditions are not met, the result of these algorithm calls is undefined.
+- ``sort``, ``stable_sort``, ``sort_by_key``, ``partial_sort_copy`` algorithms may work incorrectly or cause
+  a segmentation fault when used a DPC++ execution policy for CPU device, and built
+  on Linux with Intel® oneAPI DPC++/C++ Compiler and -O0 -g compiler options.
+  To avoid the issue, pass ``-fsycl-device-code-split=per_kernel`` option to the compiler.
+- Incorrect results may be produced by ``exclusive_scan``, ``inclusive_scan``, ``transform_exclusive_scan``,
+  ``transform_inclusive_scan``, ``exclusive_scan_by_segment``, ``inclusive_scan_by_segment``, ``reduce_by_segment``
+  with ``unseq`` or ``par_unseq`` policy when compiled by Intel® oneAPI DPC++/C++ Compiler
+  with ``-fiopenmp``, ``-fiopenmp-simd``, ``-qopenmp``, ``-qopenmp-simd`` options on Linux.
+  To avoid the issue, pass ``-fopenmp`` or ``-fopenmp-simd`` option instead.
+- Incorrect results may be produced by ``reduce``, ``reduce_by_segment``, and ``transform_reduce``
+  with 64-bit data types when compiled by Intel® oneAPI DPC++/C++ Compiler versions 2021.3 and newer
+  and executed on GPU devices.
+  For a workaround, define the ``ONEDPL_WORKAROUND_FOR_IGPU_64BIT_REDUCTION`` macro to ``1`` before
+  including oneDPL header files.
+- ``std::tuple``, ``std::pair`` cannot be used with SYCL buffers to transfer data between host and device.
+- ``std::array`` cannot be swapped in DPC++ kernels with ``std::swap`` function or ``swap`` member function
+  in the Microsoft* Visual C++ standard library.
+- The ``oneapi::dpl::experimental::ranges::reverse`` algorithm is not available with ``-fno-sycl-unnamed-lambda`` option.
+- STL algorithm functions (such as ``std::for_each``) used in DPC++ kernels do not compile with the debug version of
+  the Microsoft* Visual C++ standard library.
+
 New in 2022.5.0
 ===============
 
@@ -661,8 +745,8 @@ Known Issues and Limitations
   (including ``std::ldexp``, ``std::frexp``, ``std::sqrt(std::complex<float>)``) require device support
   for double precision.
 
-.. [#fnote1] The sorting algorithms in oneDPL use Radix sort for arithmetic data types compared with
-   ``std::less`` or ``std::greater``, otherwise Merge sort.
+.. [#fnote1] The sorting algorithms in oneDPL use Radix sort for arithmetic data types and
+   ``sycl::half`` (since oneDPL 2022.6) compared with ``std::less`` or ``std::greater``, otherwise Merge sort.
 .. _`the oneDPL Specification`: https://spec.oneapi.com/versions/latest/elements/oneDPL/source/index.html
 .. _`oneDPL Guide`: https://oneapi-src.github.io/oneDPL/index.html
 .. _`Intel® oneAPI Threading Building Blocks (oneTBB) Release Notes`: https://www.intel.com/content/www/us/en/developer/articles/release-notes/intel-oneapi-threading-building-blocks-release-notes.html
@@ -671,3 +755,4 @@ Known Issues and Limitations
 .. _`Macros`: https://oneapi-src.github.io/oneDPL/macros.html
 .. _`2022.0 Changes`: https://oneapi-src.github.io/oneDPL/oneDPL_2022.0_changes.html
 .. _`sycl device copyable`: https://registry.khronos.org/SYCL/specs/sycl-2020/html/sycl-2020.html#sec::device.copyable
+.. _`oneAPI DPC++ Library Manual Migration Guide`: https://www.intel.com/content/www/us/en/developer/articles/guide/oneapi-dpcpp-library-manual-migration.html 

include/oneapi/dpl/internal/distributed_ranges_impl/concepts/concepts.hpp

@@ -10,29 +10,25 @@ namespace oneapi::dpl::experimental::dr
 {
 
 template <typename I>
-concept remote_iterator = std::forward_iterator<I>&&
-requires(I& iter)
+concept remote_iterator = std::forward_iterator<I> && requires(I& iter)
 {
     ranges::rank(iter);
 };
 
 template <typename R>
-concept remote_range = rng::forward_range<R>&&
-requires(R& r)
+concept remote_range = rng::forward_range<R> && requires(R& r)
 {
     ranges::rank(r);
 };
 
 template <typename R>
-concept distributed_range = rng::forward_range<R>&&
-requires(R& r)
+concept distributed_range = rng::forward_range<R> && requires(R& r)
 {
     ranges::segments(r);
 };
 
 template <typename I>
-concept remote_contiguous_iterator = std::random_access_iterator<I>&&
-requires(I& iter)
+concept remote_contiguous_iterator = std::random_access_iterator<I> && requires(I& iter)
 {
     ranges::rank(iter);
     {
@@ -41,39 +37,34 @@ requires(I& iter)
 };
 
 template <typename I>
-concept distributed_iterator = std::forward_iterator<I>&&
-requires(I& iter)
+concept distributed_iterator = std::forward_iterator<I> && requires(I& iter)
 {
     ranges::segments(iter);
 };
 
 template <typename R>
-concept remote_contiguous_range = remote_range<R>&& rng::random_access_range<R>&&
-requires(R& r)
+concept remote_contiguous_range = remote_range<R> && rng::random_access_range<R> && requires(R& r)
 {
     {
         ranges::local(r)
         } -> rng::contiguous_range;
 };
 
 template <typename R>
-concept distributed_contiguous_range = distributed_range<R>&& rng::random_access_range<R>&&
-requires(R& r)
+concept distributed_contiguous_range = distributed_range<R> && rng::random_access_range<R> && requires(R& r)
 {
     {
         ranges::segments(r)
         } -> rng::random_access_range;
-}
-&&remote_contiguous_range<rng::range_value_t<decltype(ranges::segments(std::declval<R>()))>>;
+} && remote_contiguous_range<rng::range_value_t<decltype(ranges::segments(std::declval<R>()))>>;
 
 template <typename Iter>
-concept distributed_contiguous_iterator = distributed_iterator<Iter>&& std::random_access_iterator<Iter>&&
-requires(Iter& iter)
+concept distributed_contiguous_iterator = distributed_iterator<Iter> && std::random_access_iterator<Iter> &&
+    requires(Iter& iter)
 {
     {
         ranges::segments(iter)
         } -> rng::random_access_range;
-}
-&&remote_contiguous_range<rng::range_value_t<decltype(ranges::segments(std::declval<Iter>()))>>;
+} && remote_contiguous_range<rng::range_value_t<decltype(ranges::segments(std::declval<Iter>()))>>;
 
 } // namespace oneapi::dpl::experimental::dr