[libcxx-commits] [libcxx] [libc++] Vectorize mismatch (PR #73255)
via libcxx-commits
libcxx-commits at lists.llvm.org
Sat Feb 24 06:18:51 PST 2024
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-libcxx
Author: Nikolas Klauser (philnik777)
<details>
<summary>Changes</summary>
```
--------------------------------------------------
Benchmark old new
--------------------------------------------------
bm_mismatch<char>/1 10.6 ns 10.5 ns
bm_mismatch<char>/2 18.6 ns 18.6 ns
bm_mismatch<char>/3 21.4 ns 21.7 ns
bm_mismatch<char>/4 22.7 ns 23.0 ns
bm_mismatch<char>/5 23.8 ns 23.9 ns
bm_mismatch<char>/6 24.2 ns 24.5 ns
bm_mismatch<char>/7 24.4 ns 24.9 ns
bm_mismatch<char>/8 24.8 ns 25.1 ns
bm_mismatch<char>/16 26.1 ns 26.6 ns
bm_mismatch<char>/64 31.1 ns 31.3 ns
bm_mismatch<char>/512 82.1 ns 37.6 ns
bm_mismatch<char>/4096 503 ns 70.1 ns
bm_mismatch<char>/32768 3920 ns 386 ns
bm_mismatch<char>/262144 31386 ns 2988 ns
bm_mismatch<char>/1048576 123315 ns 12640 ns
bm_mismatch<short>/1 10.6 ns 10.6 ns
bm_mismatch<short>/2 19.0 ns 18.7 ns
bm_mismatch<short>/3 22.1 ns 21.7 ns
bm_mismatch<short>/4 23.5 ns 23.0 ns
bm_mismatch<short>/5 24.4 ns 23.8 ns
bm_mismatch<short>/6 25.2 ns 24.5 ns
bm_mismatch<short>/7 25.6 ns 25.0 ns
bm_mismatch<short>/8 25.8 ns 25.0 ns
bm_mismatch<short>/16 26.9 ns 26.2 ns
bm_mismatch<short>/64 32.3 ns 34.4 ns
bm_mismatch<short>/512 83.1 ns 43.1 ns
bm_mismatch<short>/4096 511 ns 138 ns
bm_mismatch<short>/32768 3966 ns 940 ns
bm_mismatch<short>/262144 31230 ns 7724 ns
bm_mismatch<short>/1048576 124324 ns 30343 ns
bm_mismatch<int>/1 10.6 ns 10.6 ns
bm_mismatch<int>/2 19.3 ns 19.0 ns
bm_mismatch<int>/3 21.9 ns 21.6 ns
bm_mismatch<int>/4 23.2 ns 22.9 ns
bm_mismatch<int>/5 23.9 ns 24.0 ns
bm_mismatch<int>/6 24.2 ns 24.6 ns
bm_mismatch<int>/7 24.6 ns 25.0 ns
bm_mismatch<int>/8 24.9 ns 25.3 ns
bm_mismatch<int>/16 26.1 ns 31.9 ns
bm_mismatch<int>/64 33.7 ns 36.6 ns
bm_mismatch<int>/512 135 ns 53.0 ns
bm_mismatch<int>/4096 978 ns 199 ns
bm_mismatch<int>/32768 7768 ns 1471 ns
bm_mismatch<int>/262144 62202 ns 12351 ns
bm_mismatch<int>/1048576 244952 ns 50080 ns
```
---
Patch is 26.41 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/73255.diff
11 Files Affected:
- (modified) libcxx/benchmarks/CMakeLists.txt (+1)
- (added) libcxx/benchmarks/algorithms/mismatch.bench.cpp (+31)
- (modified) libcxx/include/CMakeLists.txt (+1)
- (modified) libcxx/include/__algorithm/mismatch.h (+73-5)
- (added) libcxx/include/__algorithm/simd_utils.h (+114)
- (modified) libcxx/include/__bit/bit_cast.h (+9)
- (modified) libcxx/include/__bit/countr.h (+9-4)
- (modified) libcxx/include/libcxx.imp (+1)
- (modified) libcxx/include/module.modulemap.in (+5-1)
- (modified) libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp (+100-61)
- (removed) libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch_pred.pass.cpp (-119)
``````````diff
diff --git a/libcxx/benchmarks/CMakeLists.txt b/libcxx/benchmarks/CMakeLists.txt
index 2434d82c6fd6ba..0337d4fdb73aa2 100644
--- a/libcxx/benchmarks/CMakeLists.txt
+++ b/libcxx/benchmarks/CMakeLists.txt
@@ -182,6 +182,7 @@ set(BENCHMARK_TESTS
algorithms/make_heap_then_sort_heap.bench.cpp
algorithms/min.bench.cpp
algorithms/min_max_element.bench.cpp
+ algorithms/mismatch.bench.cpp
algorithms/pop_heap.bench.cpp
algorithms/pstl.stable_sort.bench.cpp
algorithms/push_heap.bench.cpp
diff --git a/libcxx/benchmarks/algorithms/mismatch.bench.cpp b/libcxx/benchmarks/algorithms/mismatch.bench.cpp
new file mode 100644
index 00000000000000..98725c8690e640
--- /dev/null
+++ b/libcxx/benchmarks/algorithms/mismatch.bench.cpp
@@ -0,0 +1,31 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <algorithm>
+#include <benchmark/benchmark.h>
+#include <random>
+
+template <class T>
+static void bm_mismatch(benchmark::State& state) {
+ std::vector<T> vec1(state.range(), '1');
+ std::vector<T> vec2(state.range(), '1');
+ std::mt19937_64 rng(std::random_device{}());
+
+ for (auto _ : state) {
+ auto idx = rng() % vec1.size();
+ vec1[idx] = '2';
+ benchmark::DoNotOptimize(vec1);
+ benchmark::DoNotOptimize(std::mismatch(vec1.begin(), vec1.end(), vec2.begin()));
+ vec1[idx] = '1';
+ }
+}
+BENCHMARK(bm_mismatch<char>)->DenseRange(1, 8)->Range(16, 1 << 20);
+BENCHMARK(bm_mismatch<short>)->DenseRange(1, 8)->Range(16, 1 << 20);
+BENCHMARK(bm_mismatch<int>)->DenseRange(1, 8)->Range(16, 1 << 20);
+
+BENCHMARK_MAIN();
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index fa3b464e56c4d0..e04e6c899bd161 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -217,6 +217,7 @@ set(files
__algorithm/shift_right.h
__algorithm/shuffle.h
__algorithm/sift_down.h
+ __algorithm/simd_utils.h
__algorithm/sort.h
__algorithm/sort_heap.h
__algorithm/stable_partition.h
diff --git a/libcxx/include/__algorithm/mismatch.h b/libcxx/include/__algorithm/mismatch.h
index d345b6048a7e9b..9cb7c6f9ff55c7 100644
--- a/libcxx/include/__algorithm/mismatch.h
+++ b/libcxx/include/__algorithm/mismatch.h
@@ -11,23 +11,89 @@
#define _LIBCPP___ALGORITHM_MISMATCH_H
#include <__algorithm/comp.h>
+#include <__algorithm/simd_utils.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
-#include <__iterator/iterator_traits.h>
+#include <__functional/identity.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__type_traits/is_equality_comparable.h>
+#include <__type_traits/operation_traits.h>
+#include <__utility/move.h>
#include <__utility/pair.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
_LIBCPP_BEGIN_NAMESPACE_STD
+template <class _Iter1, class _Sent1, class _Iter2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter1, _Iter2>
+__mismatch_loop(_Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ while (__first1 != __last1) {
+ if (!std::__invoke(__pred, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
+ break;
+ ++__first1;
+ ++__first2;
+ }
+ return std::make_pair(std::move(__first1), std::move(__first2));
+}
+
+template <class _Iter1, class _Sent1, class _Iter2, class _Pred, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter1, _Iter2>
+__mismatch(_Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ return std::__mismatch_loop(__first1, __last1, __first2, __pred, __proj1, __proj2);
+}
+
+#if _LIBCPP_VECTORIZE_ALGORIHTMS
+
+template <class _Tp,
+ class _Pred,
+ class _Proj1,
+ class _Proj2,
+ __enable_if_t<is_integral<_Tp>::value && __desugars_to<__equal_tag, _Pred, _Tp, _Tp>::value &&
+ __is_identity<_Proj1>::value && __is_identity<_Proj2>::value,
+ int> = 0>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Tp*, _Tp*>
+__mismatch(_Tp* __first1, _Tp* __last1, _Tp* __first2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ constexpr size_t __unroll_count = 4;
+ constexpr size_t __vec_size = __native_vector_size<_Tp>;
+ using __vec = __simd_vector<_Tp, __vec_size>;
+ while (!__libcpp_is_constant_evaluated() && static_cast<size_t>(__last1 - __first1) >= __unroll_count * __vec_size) {
+ __vec __lhs[__unroll_count];
+ __vec __rhs[__unroll_count];
+
+ for (size_t __i = 0; __i != __unroll_count; ++__i) {
+ __lhs[__i] = std::__load_vector<__vec>(__first1 + __i * __vec_size);
+ __rhs[__i] = std::__load_vector<__vec>(__first2 + __i * __vec_size);
+ }
+
+ for (size_t __i = 0; __i != __unroll_count; ++__i) {
+ if (auto __cmp_res = __lhs[__i] == __rhs[__i]; !std::__all_of(__cmp_res)) {
+ auto __offset = __i * __unroll_count + std::__find_first_not_set(__cmp_res);
+ return {__first1 + __offset, __first2 + __offset};
+ }
+ }
+
+ __first1 += __unroll_count * __vec_size;
+ __first2 += __unroll_count * __vec_size;
+ }
+ return std::__mismatch_loop(__first1, __last1, __first2, __pred, __proj1, __proj2);
+}
+
+#endif // _LIBCPP_VECTORIZE_ALGORIHTMS
+
template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_InputIterator1, _InputIterator2>
mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
- for (; __first1 != __last1; ++__first1, (void)++__first2)
- if (!__pred(*__first1, *__first2))
- break;
- return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
+ __identity __proj;
+ auto __res = std::__mismatch(
+ std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred, __proj, __proj);
+ return std::make_pair(std::__rewrap_iter(__first1, __res.first), std::__rewrap_iter(__first2, __res.second));
}
template <class _InputIterator1, class _InputIterator2>
@@ -59,4 +125,6 @@ mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __fi
_LIBCPP_END_NAMESPACE_STD
+_LIBCPP_POP_MACROS
+
#endif // _LIBCPP___ALGORITHM_MISMATCH_H
diff --git a/libcxx/include/__algorithm/simd_utils.h b/libcxx/include/__algorithm/simd_utils.h
new file mode 100644
index 00000000000000..72f1a775dfe9b9
--- /dev/null
+++ b/libcxx/include/__algorithm/simd_utils.h
@@ -0,0 +1,114 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SIMD_UTILS_H
+#define _LIBCPP___ALGORITHM_SIMD_UTILS_H
+
+#include <__bit/bit_cast.h>
+#include <__bit/countr.h>
+#include <__config>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 14 && __has_attribute(__ext_vector_type__) && __has_builtin(__builtin_reduce_and) && \
+ __has_builtin(__builtin_convertvector)
+# define _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS 1
+#else
+# define _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS 0
+#endif
+
+#if _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS && !defined(__OPTIMIZE_SIZE__)
+# define _LIBCPP_VECTORIZE_ALGORIHTMS 1
+#else
+# define _LIBCPP_VECTORIZE_ALGORIHTMS 0
+#endif
+
+#if _LIBCPP_HAS_ALGORITHM_VECTOR_UTILS
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+# if defined(__AVX512F__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 64 / sizeof(_Tp);
+# elif defined(__AVX__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 32 / sizeof(_Tp);
+# elif defined(__SSE__) || defined(__ARM_NEON__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 16 / sizeof(_Tp);
+# elif defined(__MMX__)
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 8 / sizeof(_Tp);
+# else
+template <class _Tp>
+inline constexpr size_t __native_vector_size = 1;
+# endif
+
+template <class _Tp, size_t _Np>
+using __simd_vector __attribute__((__ext_vector_type__(_Np))) = _Tp;
+
+template <class _VecT>
+inline constexpr size_t __simd_vector_size_v = []() -> size_t { static_assert(false, "Not a vector!"); }();
+
+template <class _Tp, size_t _Np>
+inline constexpr size_t __simd_vector_size_v<__simd_vector<_Tp, _Np>> = _Np;
+
+template <class _VecT>
+using __simd_vector_underlying_type_t = decltype([]<class _Tp, size_t _Np>() { return _Tp{}; });
+
+template <class _VecT, class _UnderlyingType = __simd_vector_underlying_type_t<_VecT>>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _VecT __load_vector(const _UnderlyingType* __ptr) noexcept {
+ return []<size_t... _Indices>(const _UnderlyingType* __lptr, index_sequence<_Indices...>) static noexcept {
+ return _VecT{__lptr[_Indices]...};
+ }(__ptr, make_index_sequence<__simd_vector_size_v<_VecT>>{});
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI bool __all_of(__simd_vector<_Tp, _Np> __vec) noexcept {
+ return __builtin_reduce_and(__builtin_convertvector(__vec, __simd_vector<bool, _Np>));
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI size_t __find_first_set(__simd_vector<_Tp, _Np> __vec) noexcept {
+ using __mask_vec = __simd_vector<bool, _Np>;
+
+ auto __impl = [&]<class _MaskT>(_MaskT) noexcept {
+ return std::__countr_zero(std::__bit_cast<_MaskT>(__builtin_convertvector(__vec, __mask_vec)));
+ };
+
+ if constexpr (sizeof(__mask_vec) == sizeof(uint8_t)) {
+ return __impl(uint8_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint16_t)) {
+ return __impl(uint16_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint32_t)) {
+ return __impl(uint32_t{});
+ } else if constexpr (sizeof(__mask_vec) == sizeof(uint64_t)) {
+ return __impl(uint64_t{});
+ } else {
+ static_assert(sizeof(__mask_vec) == 0, "unexpected required size for mask integer type");
+ }
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI size_t __find_first_not_set(__simd_vector<_Tp, _Np> __vec) noexcept {
+ return std::__find_first_set(~__vec);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 14 && __has_attribute(__ext_vector_type__) && __has_builtin(__builtin_reduce_and) &&
+ // __has_builtin(__builtin_convertvector)
+
+#endif // _LIBCPP___ALGORITHM_SIMD_UTILS_H
diff --git a/libcxx/include/__bit/bit_cast.h b/libcxx/include/__bit/bit_cast.h
index f20b39ae748b10..6298810f373303 100644
--- a/libcxx/include/__bit/bit_cast.h
+++ b/libcxx/include/__bit/bit_cast.h
@@ -19,6 +19,15 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _ToType, class _FromType>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI constexpr _ToType __bit_cast(const _FromType& __from) noexcept {
+ return __builtin_bit_cast(_ToType, __from);
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
#if _LIBCPP_STD_VER >= 20
template <class _ToType, class _FromType>
diff --git a/libcxx/include/__bit/countr.h b/libcxx/include/__bit/countr.h
index 0cc679f87a99d9..b6b3ac52ca4e47 100644
--- a/libcxx/include/__bit/countr.h
+++ b/libcxx/include/__bit/countr.h
@@ -35,10 +35,8 @@ _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_ct
return __builtin_ctzll(__x);
}
-#if _LIBCPP_STD_VER >= 20
-
-template <__libcpp_unsigned_integer _Tp>
-_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr int countr_zero(_Tp __t) noexcept {
+template <class _Tp>
+_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int __countr_zero(_Tp __t) _NOEXCEPT {
if (__t == 0)
return numeric_limits<_Tp>::digits;
@@ -59,6 +57,13 @@ _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr int countr_zero(_Tp __t) n
}
}
+#if _LIBCPP_STD_VER >= 20
+
+template <__libcpp_unsigned_integer _Tp>
+_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr int countr_zero(_Tp __t) noexcept {
+ return std::__countr_zero(__t);
+}
+
template <__libcpp_unsigned_integer _Tp>
_LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr int countr_one(_Tp __t) noexcept {
return __t != numeric_limits<_Tp>::max() ? std::countr_zero(static_cast<_Tp>(~__t)) : numeric_limits<_Tp>::digits;
diff --git a/libcxx/include/libcxx.imp b/libcxx/include/libcxx.imp
index fbe09fa5e54ab1..8b2f78b713976a 100644
--- a/libcxx/include/libcxx.imp
+++ b/libcxx/include/libcxx.imp
@@ -217,6 +217,7 @@
{ include: [ "<__algorithm/shift_right.h>", "private", "<algorithm>", "public" ] },
{ include: [ "<__algorithm/shuffle.h>", "private", "<algorithm>", "public" ] },
{ include: [ "<__algorithm/sift_down.h>", "private", "<algorithm>", "public" ] },
+ { include: [ "<__algorithm/simd_utils.h>", "private", "<algorithm>", "public" ] },
{ include: [ "<__algorithm/sort.h>", "private", "<algorithm>", "public" ] },
{ include: [ "<__algorithm/sort_heap.h>", "private", "<algorithm>", "public" ] },
{ include: [ "<__algorithm/stable_partition.h>", "private", "<algorithm>", "public" ] },
diff --git a/libcxx/include/module.modulemap.in b/libcxx/include/module.modulemap.in
index e72136a58c0b1b..79245c87b15847 100644
--- a/libcxx/include/module.modulemap.in
+++ b/libcxx/include/module.modulemap.in
@@ -697,7 +697,10 @@ module std_private_algorithm_minmax [system
export *
}
module std_private_algorithm_minmax_element [system] { header "__algorithm/minmax_element.h" }
-module std_private_algorithm_mismatch [system] { header "__algorithm/mismatch.h" }
+module std_private_algorithm_mismatch [system] {
+ header "__algorithm/mismatch.h"
+ export std_private_algorithm_simd_utils
+}
module std_private_algorithm_move [system] { header "__algorithm/move.h" }
module std_private_algorithm_move_backward [system] { header "__algorithm/move_backward.h" }
module std_private_algorithm_next_permutation [system] { header "__algorithm/next_permutation.h" }
@@ -1048,6 +1051,7 @@ module std_private_algorithm_sort [system
header "__algorithm/sort.h"
export std_private_debug_utils_strict_weak_ordering_check
}
+module std_private_algorithm_simd_utils [system] { header "__algorithm/simd_utils.h" }
module std_private_algorithm_sort_heap [system] { header "__algorithm/sort_heap.h" }
module std_private_algorithm_stable_partition [system] { header "__algorithm/stable_partition.h" }
module std_private_algorithm_stable_sort [system] { header "__algorithm/stable_sort.h" }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
index cc588c095ccfb2..faaef5377863b8 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
@@ -16,78 +16,117 @@
// template<InputIterator Iter1, InputIterator Iter2Pred>
// constexpr pair<Iter1, Iter2> // constexpr after c++17
// mismatch(Iter1 first1, Iter1 last1, Iter2 first2, Iter2 last2); // C++14
+//
+// template<InputIterator Iter1, InputIterator Iter2,
+// Predicate<auto, Iter1::value_type, Iter2::value_type> Pred>
+// requires CopyConstructible<Pred>
+// constexpr pair<Iter1, Iter2> // constexpr after c++17
+// mismatch(Iter1 first1, Iter1 last1, Iter2 first2, Pred pred);
+//
+// template<InputIterator Iter1, InputIterator Iter2, Predicate Pred>
+// constexpr pair<Iter1, Iter2> // constexpr after c++17
+// mismatch(Iter1 first1, Iter1 last1, Iter2 first2, Iter2 last2, Pred pred); // C++14
+
+// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-steps): -fconstexpr-steps=20000000
+// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-ops-limit): -fconstexpr-ops-limit=100000000
#include <algorithm>
+#include <array>
#include <cassert>
+#include <vector>
#include "test_macros.h"
#include "test_iterators.h"
-
-#if TEST_STD_VER > 17
-TEST_CONSTEXPR bool test_constexpr() {
- int ia[] = {1, 3, 6, 7};
- int ib[] = {1, 3};
- int ic[] = {1, 3, 5, 7};
- typedef cpp17_input_iterator<int*> II;
- typedef bidirectional_iterator<int*> BI;
-
- auto p1 = std::mismatch(std::begin(ia), std::end(ia), std::begin(ic));
- if (p1.first != ia+2 || p1.second != ic+2)
- return false;
-
- auto p2 = std::mismatch(std::begin(ia), std::end(ia), std::begin(ic), std::end(ic));
- if (p2.first != ia+2 || p2.second != ic+2)
- return false;
-
- auto p3 = std::mismatch(std::begin(ib), std::end(ib), std::begin(ic));
- if (p3.first != ib+2 || p3.second != ic+2)
- return false;
-
- auto p4 = std::mismatch(std::begin(ib), std::end(ib), std::begin(ic), std::end(ic));
- if (p4.first != ib+2 || p4.second != ic+2)
- return false;
-
- auto p5 = std::mismatch(II(std::begin(ib)), II(std::end(ib)), II(std::begin(ic)));
- if (p5.first != II(ib+2) || p5.second != II(ic+2))
- return false;
- auto p6 = std::mismatch(BI(std::begin(ib)), BI(std::end(ib)), BI(std::begin(ic)), BI(std::end(ic)));
- if (p6.first != BI(ib+2) || p6.second != BI(ic+2))
- return false;
-
- return true;
- }
+#include "type_algorithms.h"
+
+template <class Iter, class Container1, class Container2>
+TEST_CONSTEXPR_CXX20 void check(Container1 lhs, Container2 rhs, size_t offset) {
+ if (lhs.size() == rhs.size()) {
+ assert(std::mismatch(Iter(lhs.data()), Iter(lhs.data() + lhs.size()), Iter(rhs.data())) ==
+ std::make_pair(Iter(lhs.data() + offset), Iter(rhs.data() + offset)));
+
+ assert(std::mismatch(Iter(lhs.data()), Iter(lhs.data() + lhs.size()), Iter(rhs.data()), std::equal_to<int>()) ==
+ std::make_pair(Iter(lhs.data() + offset), Iter(rhs.data() + offset)));
+ }
+
+#if TEST_STD_VER >= 14
+ assert(
+ std::mismatch(Iter(lhs.data()), Iter(lhs.data() + lhs.size()), Iter(rhs.data()), Iter(rhs.data() + rhs.size())) ==
+ std::make_pair(Iter(lhs.data() + offset), Iter(rhs.data() + offset)));
+
+ assert(std::mismatch(Iter(lhs.data()),
+ Iter(lhs.data() + lhs.size()),
+ Iter(rhs.data()),
+ Iter(rhs.data() + rhs.size()),
+ std::equal_to<int>()) == std::make_pair(Iter(lhs.data() + offset), Iter(rhs.data() + offset)));
#endif
+}
-int main(int, char**)
-{
- int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
- const unsigned sa = sizeof(ia)/sizeof(ia[0]);
- int ib[] = {0, 1, 2, 3, 0, 1, 2, 3};
- const unsigned sb = sizeof(ib)/sizeof(ib[0]); ((void)sb); // unused in C++11
-
- typedef cpp17_input_iterator<const int*> II;
- typedef random_access_iterator<const int*> RAI;
-
- assert(std::mismatch(II(ia), II(ia + sa), II(ib))
- == (std::pair<II, II>(II(ia+3), II(ib+3))));
-
- assert(std::mismatch(RAI(ia), RAI(ia + sa), RAI(ib))
- == (std::pair<RAI, RAI>(RAI(ia+3), RAI(ib+3))));
-
-#if TEST_STD_VER > 11 // We have the four iteration version
- assert(std::mismatch(II(ia), II(ia + sa), II(ib), II(ib+sb))
- == (std::pair<II, II>(II(ia+3), II(ib+3))));
-
- assert(std::mismatch(RAI(ia), RAI(ia + s...
[truncated]
``````````
</details>
https://github.com/llvm/llvm-project/pull/73255
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