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The list of most significant changes made over time in Parallel STL.

Parallel STL release within Intel(R) Parallel Studio XE 2020 Update 1
__INTEL_PSTL_VERSION == 211

Features / APIs:

- Added support for GCC9 compiler where libstdc++ contains implemented
    C++17 standard execution policies.

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Parallel STL release within Intel(R) Parallel Studio XE 2020
__INTEL_PSTL_VERSION == 210

Features / APIs:

- Renamed versioning macros to __INTEL_PSTL_VERSION, __INTEL_PSTL_VERSION_MAJOR,
    __INTEL_PSTL_VERSION_MINOR. The upstream code version can be checked with
    _PSTL_VERSION and its derivatives.

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Parallel STL 20190522 release
PSTL_VERSION == 207

Features / APIs:

- Added for_loop algorithm family from the Parallelism TS v2
    (working draft N4808) with support for sequenced_policy
    and parallel_policy.
- The following algorithms support parallel_policy with forward
    iterators: transform, for_each.

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Parallel STL release within Intel(R) Parallel Studio XE 2019 Update 4
PSTL_VERSION == 206

Features / APIs:

- Improved performance in equal algorithm.

Bugs fixed:
- Fixed an error with multiple invocations of FindTBB.cmake
  (https://github.com/intel/parallelstl/issues/26).

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Parallel STL 20190321 release
PSTL_VERSION == 205

Features / APIs:

- Improved performance in stable_sort and sort algorithms.

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Parallel STL release within Intel(R) Parallel Studio XE 2019 Update 3
PSTL_VERSION == 204

Bugs fixed:
- Fixed compilation error for usage of PSTL_USE_PARALLEL_POLICIES macro.
- Fixed compilation error for reordering standard included files.

Examples:

- Added CMake support for convex_hull and dot_product samples.

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Parallel STL 20181204 release
PSTL_VERSION == 203

Features / APIs:

- More algorithms support parallel execution policies:
    set_union, set_intersection, set_difference, set_symmetric_difference.
- Improved performance in reverse, reverse_copy algorithm with vector
    execution policies.
- Added FindTBB CMake module - Preview Feature.

Bugs fixed:

- Fixed several algorithms which use scan and reduction patterns with
    a user defined binary operation with vector execution policies.

Examples:

- CMake support for gamma_correction sample was added.

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Parallel STL release within Intel(R) Parallel Studio XE 2019 Update 1
PSTL_VERSION == 202

Features / APIs:

- Fixed compilation error for reduce and transform_reduce algorithms
    with Microsoft* Visual Studio 2017 15.8.

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Parallel STL 20181004 release
PSTL_VERSION == 201

Features / APIs:

- Fixed a number of algorithms to work with mutable function objects.
- Fixed algorithms to throw std::bad_alloc when additional memory cannot
    be obtained.

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Parallel STL release within Intel(R) Parallel Studio XE 2019
PSTL_VERSION == 200

Features / APIs:

- More algorithms support parallel and vector execution policies:
    rotate.
- More algorithms support parallel execution policies:
    includes, nth_element, remove, remove_if, unique.
- More algorithms support vector execution policies:
    exclusive_scan, inclusive_scan, max_element, minmax_element,
    min_element, reduce, transform_exclusive_scan, transform_inclusive_scan,
    transform_reduce.
- Arranged types and variables naming: single- and double-underscore.
    (by Thomas Rodgers).

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Parallel STL 20180619 release
PSTL_VERSION == 106

Features / APIs:

- More algorithms support parallel and vector execution policies:
    adjacent_difference, partition, reverse, reverse_copy, rotate_copy,
    stable_partition.
- More algorithms support parallel execution policies:
    inplace_merge, partial_sort_copy.
- Split algorithm declarations and implementation by files.
    (by Thomas Rodgers).
- CMake support - Preview Feature
    (by Amit Prakash Ambasta and Henry Schreiner)

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Parallel STL release within Intel(R) Parallel Studio XE 2018 Update 3
PSTL_VERSION == 105

Features / APIs:

- More algorithms support parallel and vector execution policies:
    is_partitioned, lexicographical_compare, swap_ranges.
- Added specialization of parallel_transform_scan pattern for better
    performance with floating point types.
- Arranged iterator types in public interface according to the standard
    (by Thomas Rodgers).

Bugs fixed:

- Fixed an error in parallel version of partial_sort algorithm.
- Fixed an error in equal algorithm connected with values comparison.

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Parallel STL 20180329 release
PSTL_VERSION == 104

Features / APIs:

- More algorithms support parallel and vector execution policies:
    find_first_of, is_heap, is_heap_until, replace, replace_if.
- More algorithms support vector execution policies:
    remove, remove_if.
- More algorithms support parallel execution policies:
    partial_sort.

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Parallel STL release within Intel(R) Parallel Studio XE 2018 Update 2
PSTL_VERSION == 103

Features / APIs:

- More algorithms support parallel and/or vector execution policies:
    find_end, merge, search, search_n

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Parallel STL 20171127 release
PSTL_VERSION == 102

Features / APIs:

- Added Parallel STL version macros:
    PSTL_VERSION, PSTL_VERSION_MAJOR, PSTL_VERSION_MINOR.
- More algorithms support parallel and vector execution policies:
    move, partition_copy, mismatch.
- More algorithms support parallel execution policies:
    min_element, max_element, minmax_element.

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Parallel STL release within Intel(R) Parallel Studio XE 2018 Update 1

Features / APIs:

- More algorithms support parallel and vector execution policies:
    destroy, destroy_n, uninitialized_copy, uninitialized_copy_n,
    uninitialized_default_construct, uninitialized_default_construct_n,
    uninitialized_fill, uninitialized_fill_n, uninitialized_move,
    uninitialized_move_n, uninitialized_value_construct,
    uninitialized_value_construct_n.
- Improved performance in find_end and search algorithms.
- Added macro PSTL_USE_NONTEMPORAL_STORES that can improve performance
    of copy, copy_n, fill, fill_n, generate, generate_n algorithms with
    unseq and par_unseq policies; by default the macro is not defined.

Bugs fixed:

- Fixed transform_inclusive_scan to correctly process the first element.
- Fixed compile time error in sort algorithm when used with zip_iterator
    and some other custom iterator types.
- Fixed several algorithms to allow use of non-const functors.

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Parallel STL release within Intel(R) Parallel Studio XE 2018

Features / APIs:

- Aligned the implementation with the draft N4659 of the C++ standard.
    In particular, inner_product no longer supports execution policies.
- reduce and transform_reduce support unseq and par_unseq execution
    policies if std::plus<> is used for reduction.
- Added counting_iterator and zip_iterator to support advanced use cases.
   To use, include pstl/iterators.h header file.
- Added macro PSTL_USE_PARALLEL_POLICIES to control usage of parallel
    execution policies (par, par_unseq); by default these are enabled.

Examples:

- Added dot_product and convex_hull samples to demonstrate Parallel STL
    usage.

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Parallel STL beta update release

Features / APIs:

- sequenced_policy is supported by all C++17 algorithms.
- Added other execution policies support for inner_product algorithm.

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Parallel STL beta initial release

Features / APIs:

- Implemented C++17 execution policies: sequenced_policy,
    parallel_policy, parallel_unsequenced_policy.
- Implemented unsequenced_policy based on the ISO C++ working group
    paper P0076R3.
- sequenced_policy is supported by all except a few C++17 algorithms.
- Other execution policies are supported by the following algorithms:
    adjacent_find, all_of, any_of, copy, copy_if, copy_n, count,
    count_if, equal, exclusive_scan, fill, fill_n, find, find_if,
    find_if_not, for_each, for_each_n, generate, generate_n,
    inclusive_scan, none_of, is_sorted, is_sorted_until, reduce,
    remove_copy, remove_copy_if, sort, stable_sort, transform,
    transform_exclusive_scan, transform_inclusive_scan,
    transform_reduce, unique_copy.

Documentation:

- Initial set of documents: Getting Started Guide, Release Notes.

Examples:

- Added gamma_correction sample to demonstrate Parallel STL usage.

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