Add ranges::remove_copy[_if]

include/oneapi/dpl/pstl/glue_algorithm_ranges_impl.h

@@ -196,6 +196,7 @@ struct __find_fn
     std::ranges::borrowed_iterator_t<_R>
     operator()(_ExecutionPolicy&& __exec, _R&& __r, const _T& __value, _Proj __proj = {}) const
     {
+        // TODO: make sure std::ranges::equal_to is used for comparison
         return oneapi::dpl::ranges::find_if(std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r),
             oneapi::dpl::__internal::__equal_value<oneapi::dpl::__internal::__ref_or_copy<_ExecutionPolicy,
             const _T>>(__value), __proj);
@@ -433,6 +434,7 @@ struct __count_fn
     operator()(_ExecutionPolicy&& __exec, _R&& __r, const _T& __value, _Proj __proj = {}) const
     {
         const auto __dispatch_tag = oneapi::dpl::__ranges::__select_backend(__exec);
+        // TODO: make sure std::ranges::equal_to is used for comparison
         return oneapi::dpl::__internal::__ranges::__pattern_count(__dispatch_tag,
             std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r), __value, __proj);
     }
@@ -1070,6 +1072,7 @@ struct __replace_fn
     operator()(_ExecutionPolicy&& __exec, _R&& __r, const _T1& __old_value, const _T2& __new_value,
                _Proj __proj = {}) const
     {
+        // TODO: make sure std::ranges::equal_to is used for comparison
         return oneapi::dpl::ranges::replace_if(
             std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r),
             oneapi::dpl::__internal::__equal_value<oneapi::dpl::__internal::__ref_or_copy<_ExecutionPolicy, const _T1>>(
@@ -1229,17 +1232,16 @@ struct __mismatch_fn
 
 inline constexpr __internal::__mismatch_fn mismatch;
 
-// [alg.remove_if]
+// [alg.remove]
 
 namespace __internal
 {
-
 struct __remove_if_fn
 {
-    template<typename _ExecutionPolicy, std::ranges::random_access_range _R, typename _Proj = std::identity,
-         std::indirect_unary_predicate<std::projected<std::ranges::iterator_t<_R>, _Proj>> _Pred>
+    template <typename _ExecutionPolicy, std::ranges::random_access_range _R, typename _Proj = std::identity,
+              std::indirect_unary_predicate<std::projected<std::ranges::iterator_t<_R>, _Proj>> _Pred>
     requires oneapi::dpl::is_execution_policy_v<std::remove_cvref_t<_ExecutionPolicy>>
-        && std::permutable<std::ranges::iterator_t<_R>> && std::ranges::sized_range<_R>
+             && std::ranges::sized_range<_R> && std::permutable<std::ranges::iterator_t<_R>>
 
     std::ranges::borrowed_subrange_t<_R>
     operator()(_ExecutionPolicy&& __exec, _R&& __r, _Pred __pred, _Proj __proj = {}) const
@@ -1248,36 +1250,74 @@ struct __remove_if_fn
         return oneapi::dpl::__internal::__ranges::__pattern_remove_if(__dispatch_tag,
             std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r), __pred, __proj);
     }
-
 }; //__remove_if_fn
 } //__internal
 
 inline constexpr __internal::__remove_if_fn remove_if;
 
-// [alg.remove]
-
 namespace __internal
 {
-
 struct __remove_fn
 {
-    template<typename _ExecutionPolicy, std::ranges::random_access_range _R, typename _Proj = std::identity,
-             typename _T = oneapi::dpl::projected_value_t<std::ranges::iterator_t<_R>, _Proj>>
+    template <typename _ExecutionPolicy, std::ranges::random_access_range _R, typename _Proj = std::identity,
+              typename _T = oneapi::dpl::projected_value_t<std::ranges::iterator_t<_R>, _Proj>>
     requires oneapi::dpl::is_execution_policy_v<std::remove_cvref_t<_ExecutionPolicy>>
-        && std::permutable<std::ranges::iterator_t<_R>> && std::indirect_binary_predicate<std::ranges::equal_to,
-            std::projected<std::ranges::iterator_t<_R>, _Proj>, const _T*> && std::ranges::sized_range<_R>
+             && std::ranges::sized_range<_R> && std::permutable<std::ranges::iterator_t<_R>>
+             && std::indirect_binary_predicate<std::ranges::equal_to,
+                                               std::projected<std::ranges::iterator_t<_R>, _Proj>, const _T*>
 
     std::ranges::borrowed_subrange_t<_R>
     operator()(_ExecutionPolicy&& __exec, _R&& __r, const _T& __value, _Proj __proj = {}) const
     {
+        // TODO: change lambda to a special functor
         return oneapi::dpl::ranges::remove_if(std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r),
             [__value](auto&& __a) { return std::ranges::equal_to{}(__a, __value);}, __proj);
     }
-
 }; //__remove_fn
+
+struct __remove_copy_if_fn
+{
+    template <typename _ExecutionPolicy, std::ranges::random_access_range _R, std::ranges::random_access_range _OutR,
+              typename _Proj = std::identity,
+              std::indirect_unary_predicate<std::projected<std::ranges::iterator_t<_R>, _Proj>> _Pred>
+    requires oneapi::dpl::is_execution_policy_v<std::remove_cvref_t<_ExecutionPolicy>>
+             && std::ranges::sized_range<_R> && std::ranges::sized_range<_OutR>
+             && std::indirectly_copyable<std::ranges::iterator_t<_R>, std::ranges::iterator_t<_OutR>>
+
+    std::ranges::remove_copy_if_result<std::ranges::borrowed_iterator_t<_R>, std::ranges::borrowed_iterator_t<_OutR>>
+    operator()(_ExecutionPolicy&& __exec, _R&& __r, _OutR&& __out_r, _Pred __pred, _Proj __proj = {}) const
+    {
+        return oneapi::dpl::ranges::copy_if(std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r),
+            std::forward<_OutR>(__out_r), oneapi::dpl::__internal::__not_pred<
+                oneapi::dpl::__internal::__ref_or_copy<_ExecutionPolicy, _Pred>>(__pred), __proj);
+    }
+}; //__remove_copy_if_fn
+
+struct __remove_copy_fn
+{
+    template <typename _ExecutionPolicy, std::ranges::random_access_range _R, std::ranges::random_access_range _OutR,
+              typename _Proj = std::identity,
+              typename _T = oneapi::dpl::projected_value_t<std::ranges::iterator_t<_R>, _Proj>>
+    requires oneapi::dpl::is_execution_policy_v<std::remove_cvref_t<_ExecutionPolicy>>
+             && std::ranges::sized_range<_R> && std::ranges::sized_range<_OutR>
+             && std::indirectly_copyable<std::ranges::iterator_t<_R>, std::ranges::iterator_t<_OutR>>
+             && std::indirect_binary_predicate<std::ranges::equal_to,
+                                               std::projected<std::ranges::iterator_t<_R>, _Proj>, const _T*>
+
+    std::ranges::remove_copy_result<std::ranges::borrowed_iterator_t<_R>, std::ranges::borrowed_iterator_t<_OutR>>
+    operator()(_ExecutionPolicy&& __exec, _R&& __r, _OutR&& __out_r, const _T& __value, _Proj __proj = {}) const
+    {
+        // TODO: make sure std::ranges::equal_to is used for comparison
+        return oneapi::dpl::ranges::copy_if(std::forward<_ExecutionPolicy>(__exec), std::forward<_R>(__r),
+            std::forward<_OutR>(__out_r), oneapi::dpl::__internal::__not_equal_value<
+                oneapi::dpl::__internal::__ref_or_copy<_ExecutionPolicy, const _T>>(__value), __proj);
+    }
+}; //__remove_copy_fn
 } //__internal
 
 inline constexpr __internal::__remove_fn remove;
+inline constexpr __internal::__remove_copy_if_fn remove_copy_if;
+inline constexpr __internal::__remove_copy_fn remove_copy;
 
 // [alg.unique]
 

test/parallel_api/ranges/std_ranges_remove_copy.pass.cpp

@@ -0,0 +1,120 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Copyright (C) UXL Foundation Contributors
+//
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "std_ranges_test.h"
+
+#if _ENABLE_STD_RANGES_TESTING
+#include <initializer_list>
+
+struct
+{
+    template <std::ranges::random_access_range InRange, std::ranges::random_access_range OutRange,
+              typename V, typename Proj = std::identity>
+    auto operator()(InRange&& r_in, OutRange&& r_out, const V& value, Proj proj = {})
+    {
+        using ret_type = std::ranges::remove_copy_result<std::ranges::borrowed_iterator_t<InRange>,
+                                                         std::ranges::borrowed_iterator_t<OutRange>>;
+        auto in = std::ranges::begin(r_in);
+        auto out = std::ranges::begin(r_out);
+        std::size_t i = 0, j = 0;
+        for(; i < std::ranges::size(r_in); ++i)
+        {
+             if (!std::ranges::equal_to{}(std::invoke(proj, in[i]), value))
+             {
+                 if (j < std::ranges::size(r_out))
+                     out[j++] = in[i];
+                 else
+                     break;
+             }
+        }
+        return ret_type{in + i, out + j};
+    }
+
+    void test_self()
+    {
+#if TEST_CPP20_SPAN_PRESENT
+        int input[10] = {0,0, 1, 2,2, 8, 1,1,1, 8};
+        int output[9] = {-9, -8, -7, -6, -5, -4, -3, -2, -1};
+
+        // Define test cases with expected outputs and expected end positions
+        struct TestCase {
+            int in_size;
+            int out_size;
+            std::initializer_list<int> expected_output;
+            int expected_in_end;
+            int expected_out_end;
+        } test_cases[] = {
+        // insz, outsz,  expected,  instop, outstop
+            {0,  0, {},                 0,  0}, // Empty ranges
+            {10, 0, {},                 0,  0}, // Empty output range
+            {1,  1, {0},                1,  1}, // One element ranges
+            {10, 1, {0},                1,  1}, // One element output range
+            {10, 5, {0, 0, 2, 2, 8},    9,  5}, // Output range is not big enough
+            {10, 6, {0, 0, 2, 2, 8, 8}, 10, 6}, // Output range is just enough
+            {10, 7, {0, 0, 2, 2, 8, 8}, 10, 6}, // Output range is bigger than needed
+        };
+
+        auto& self = *this;
+        for (const TestCase& test_case : test_cases) {
+            constexpr int shift = 1;
+            std::span<int> in_span(input, test_case.in_size);
+            std::span<int> out_span(output + shift, test_case.out_size);
+
+            auto result = self(in_span, out_span, 1);
+
+            // Verify the returned iterators point to the correct end positions
+            EXPECT_EQ(in_span.begin() + test_case.expected_in_end, result.in, "Checker problem: wrong input stop");
+            EXPECT_EQ(out_span.begin() + test_case.expected_out_end, result.out, "Checker problem: wrong output stop");
+
+            // Verify the output matches the expected result and nothing is overwritten
+            for (int i = 0; i < 9; ++i)
+            {
+                if (i < shift || i >= shift + test_case.expected_out_end)
+                {
+                    EXPECT_EQ(i - 9, output[i], "Checker problem: out of range modification");
+                }
+                else
+                {
+                    EXPECT_EQ(test_case.expected_output.begin()[i - shift], output[i], "Checker problem: wrong output");
+                    output[i] = i - 9; // Restore the original output data
+                }
+            }
+        }
+#endif // TEST_CPP20_SPAN_PRESENT
+    }
+} remove_copy_checker;
+#endif // _ENABLE_STD_RANGES_TESTING
+
+std::int32_t
+main()
+{
+#if _ENABLE_STD_RANGES_TESTING
+    using namespace test_std_ranges;
+    namespace dpl_ranges = oneapi::dpl::ranges;
+
+    auto almost_always_two = [](auto i) {
+        if (i%7 > 0 && (i - 1)%3 == 0)
+            return i;
+        return 2;
+    };
+    using many_twos = decltype(almost_always_two);
+
+    remove_copy_checker.test_self();
+
+    test_range_algo<0, int, data_in_out_lim>{179}(dpl_ranges::remove_copy, remove_copy_checker, 0);
+    test_range_algo<1, int, data_in_out_lim, many_twos>{1127}(dpl_ranges::remove_copy, remove_copy_checker, 2);
+    test_range_algo<2, int, data_in_out_lim>{}(dpl_ranges::remove_copy, remove_copy_checker, 1, proj);
+    test_range_algo<3, P2, data_in_out_lim, many_twos>{}(dpl_ranges::remove_copy, remove_copy_checker, 2, &P2::x);
+    test_range_algo<4, P2, data_in_out_lim>{}(dpl_ranges::remove_copy, remove_copy_checker, 0, &P2::proj);
+    test_range_algo<5, int, data_in_out_lim>{big_sz}(dpl_ranges::remove_copy, remove_copy_checker, 1);
+    test_range_algo<6, int, data_in_out_lim, many_twos>{big_sz}(dpl_ranges::remove_copy, remove_copy_checker, 2);
+#endif // _ENABLE_STD_RANGES_TESTING
+
+    return TestUtils::done(_ENABLE_STD_RANGES_TESTING);
+}

test/parallel_api/ranges/std_ranges_remove_copy_if.pass.cpp

@@ -0,0 +1,125 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Copyright (C) UXL Foundation Contributors
+//
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "std_ranges_test.h"
+
+#if _ENABLE_STD_RANGES_TESTING
+#include <initializer_list>
+
+struct
+{
+    template <std::ranges::random_access_range InRange, std::ranges::random_access_range OutRange,
+              typename Pred, typename Proj = std::identity>
+    auto operator()(InRange&& r_in, OutRange&& r_out, Pred pred, Proj proj = {})
+    {
+        using ret_type = std::ranges::remove_copy_if_result<std::ranges::borrowed_iterator_t<InRange>,
+                                                            std::ranges::borrowed_iterator_t<OutRange>>;
+        auto in = std::ranges::begin(r_in);
+        auto out = std::ranges::begin(r_out);
+        std::size_t i = 0, j = 0;
+        for(; i < std::ranges::size(r_in); ++i)
+        {
+             if (!std::invoke(pred, std::invoke(proj, in[i])))
+             {
+                 if (j < std::ranges::size(r_out))
+                     out[j++] = in[i];
+                 else
+                     break;
+             }
+        }
+        return ret_type{in + i, out + j};
+    }
+
+    void test_self()
+    {
+#if TEST_CPP20_SPAN_PRESENT
+        int input[10] = {0,0, 1, 2,2, 8, 1,1,1, 8};
+        int output[9] = {-9, -8, -7, -6, -5, -4, -3, -2, -1};
+
+        // Define test cases with expected outputs and expected end positions
+        struct TestCase {
+            int in_size;
+            int out_size;
+            std::initializer_list<int> expected_output;
+            int expected_in_end;
+            int expected_out_end;
+        } test_cases[] = {
+        // insz, outsz,  expected,  instop, outstop
+            {0,  0, {},                 0,  0}, // Empty ranges
+            {10, 0, {},                 0,  0}, // Empty output range
+            {1,  1, {0},                1,  1}, // One element ranges
+            {10, 1, {0},                1,  1}, // One element output range
+            {10, 5, {0, 0, 2, 2, 8},    9,  5}, // Output range is not big enough
+            {10, 6, {0, 0, 2, 2, 8, 8}, 10, 6}, // Output range is just enough
+            {10, 7, {0, 0, 2, 2, 8, 8}, 10, 6}, // Output range is bigger than needed
+        };
+
+        auto& self = *this;
+        for (const TestCase& test_case : test_cases) {
+            constexpr int shift = 1;
+            std::span<int> in_span(input, test_case.in_size);
+            std::span<int> out_span(output + shift, test_case.out_size);
+
+            auto result = self(in_span, out_span, [](int v){ return v == 1; });
+
+            // Verify the returned iterators point to the correct end positions
+            EXPECT_EQ(in_span.begin() + test_case.expected_in_end, result.in, "Checker problem: wrong input stop");
+            EXPECT_EQ(out_span.begin() + test_case.expected_out_end, result.out, "Checker problem: wrong output stop");
+
+            // Verify the output matches the expected result and nothing is overwritten
+            for (int i = 0; i < 9; ++i)
+            {
+                if (i < shift || i >= shift + test_case.expected_out_end)
+                {
+                    EXPECT_EQ(i - 9, output[i], "Checker problem: out of range modification");
+                }
+                else
+                {
+                    EXPECT_EQ(test_case.expected_output.begin()[i - shift], output[i], "Checker problem: wrong output");
+                    output[i] = i - 9; // Restore the original output data
+                }
+            }
+        }
+#endif // TEST_CPP20_SPAN_PRESENT
+    }
+} remove_copy_if_checker;
+#endif // _ENABLE_STD_RANGES_TESTING
+
+std::int32_t
+main()
+{
+#if _ENABLE_STD_RANGES_TESTING
+    using namespace test_std_ranges;
+    namespace dpl_ranges = oneapi::dpl::ranges;
+
+    // input generator with a fair chance of repeating the previous value
+    auto repeat_sometimes = [](auto i) {
+        static decltype(i) last = 0;
+        if (i == 0)
+            last = 0; // reset
+        else if (i%7 > 0 && (last + i - 1)%3 == 0)
+            last = i;
+        return last;
+    };
+    using repeating_gen = decltype(repeat_sometimes);
+    auto modulo_3_is_1 = [](int val) { return (val % 3) == 1; };
+
+    remove_copy_if_checker.test_self();
+
+    test_range_algo<0, int, data_in_out_lim>{239}(dpl_ranges::remove_copy_if, remove_copy_if_checker, pred);
+    test_range_algo<1, int, data_in_out_lim>{1471}(dpl_ranges::remove_copy_if, remove_copy_if_checker, select_many);
+    test_range_algo<2, int, data_in_out_lim>{}(dpl_ranges::remove_copy_if, remove_copy_if_checker, select_many, proj);
+    test_range_algo<3, P2, data_in_out_lim, repeating_gen>{}(dpl_ranges::remove_copy_if, remove_copy_if_checker, modulo_3_is_1, &P2::x);
+    test_range_algo<4, P2, data_in_out_lim>{}(dpl_ranges::remove_copy_if, remove_copy_if_checker, pred, &P2::proj);
+    test_range_algo<5, int, data_in_out_lim>{big_sz}(dpl_ranges::remove_copy_if, remove_copy_if_checker, pred);
+    test_range_algo<6, int, data_in_out_lim, repeating_gen>{big_sz}(dpl_ranges::remove_copy_if, remove_copy_if_checker, select_many);
+#endif // _ENABLE_STD_RANGES_TESTING
+
+    return TestUtils::done(_ENABLE_STD_RANGES_TESTING);
+}