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Fix ambiguous call in ranges::count & std::count for vector<bool>::iterator
1 parent 7532958 commit d244814

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6 files changed

+249
-51
lines changed

6 files changed

+249
-51
lines changed

‎libcxx/include/__algorithm/count.h‎

Lines changed: 5 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -55,18 +55,18 @@ __count_bool(__bit_iterator<_Cp, _IsConst> __first, typename _Cp::size_type __n)
5555
if (__first.__ctz_ != 0) {
5656
__storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_);
5757
__storage_type __dn = std::min(__clz_f, __n);
58-
__storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
59-
__r = std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
58+
__storage_type __m = std::__middle_mask<__storage_type>(__first.__ctz_, __clz_f - __dn);
59+
__r = std::__popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_) & __m));
6060
__n -= __dn;
6161
++__first.__seg_;
6262
}
6363
// do middle whole words
6464
for (; __n >= __bits_per_word; ++__first.__seg_, __n -= __bits_per_word)
65-
__r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_));
65+
__r += std::__popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_)));
6666
// do last partial word
6767
if (__n > 0) {
68-
__storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
69-
__r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
68+
__storage_type __m = std::__trailing_mask<__storage_type>(__bits_per_word - __n);
69+
__r += std::__popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_) & __m));
7070
}
7171
return __r;
7272
}

‎libcxx/include/__bit/popcount.h‎

Lines changed: 72 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -15,6 +15,8 @@
1515
#include <__bit/rotate.h>
1616
#include <__concepts/arithmetic.h>
1717
#include <__config>
18+
#include <__type_traits/enable_if.h>
19+
#include <__type_traits/is_unsigned.h>
1820
#include <limits>
1921

2022
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -38,31 +40,87 @@ inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __libcpp_popcount(unsigned lo
3840
return __builtin_popcountll(__x);
3941
}
4042

41-
#if _LIBCPP_STD_VER >= 20
42-
43-
template <__libcpp_unsigned_integer _Tp>
44-
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int popcount(_Tp __t) noexcept {
45-
# if __has_builtin(__builtin_popcountg)
46-
return __builtin_popcountg(__t);
47-
# else // __has_builtin(__builtin_popcountg)
48-
if (sizeof(_Tp) <= sizeof(unsigned int))
43+
#if _LIBCPP_STD_VER >= 17
44+
// Implementation using constexpr if for C++ standards >= 17
45+
template <class _Tp, __enable_if_t<is_unsigned<_Tp>::value, int> = 0>
46+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 int __popcount(_Tp __t) _NOEXCEPT {
47+
if constexpr (sizeof(_Tp) <= sizeof(unsigned int)) {
4948
return std::__libcpp_popcount(static_cast<unsigned int>(__t));
50-
else if (sizeof(_Tp) <= sizeof(unsigned long))
49+
} else if constexpr (sizeof(_Tp) <= sizeof(unsigned long)) {
5150
return std::__libcpp_popcount(static_cast<unsigned long>(__t));
52-
else if (sizeof(_Tp) <= sizeof(unsigned long long))
51+
} else if constexpr (sizeof(_Tp) <= sizeof(unsigned long long)) {
5352
return std::__libcpp_popcount(static_cast<unsigned long long>(__t));
54-
else {
53+
} else {
5554
int __ret = 0;
5655
while (__t != 0) {
5756
__ret += std::__libcpp_popcount(static_cast<unsigned long long>(__t));
58-
__t >>= numeric_limits<unsigned long long>::digits;
57+
__t >>= std::numeric_limits<unsigned long long>::digits;
5958
}
6059
return __ret;
6160
}
62-
# endif // __has_builtin(__builtin_popcountg)
6361
}
6462

65-
#endif // _LIBCPP_STD_VER >= 20
63+
#else
64+
// Equivalent SFINAE-based implementation for older C++ standards < 17
65+
66+
template < class _Tp, __enable_if_t<is_unsigned<_Tp>::value && sizeof(_Tp) <= sizeof(unsigned int), int> = 0>
67+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __popcount(_Tp __t) _NOEXCEPT {
68+
return std::__libcpp_popcount(static_cast<unsigned int>(__t));
69+
}
70+
71+
template < class _Tp,
72+
__enable_if_t<is_unsigned<_Tp>::value && (sizeof(_Tp) > sizeof(unsigned int)) &&
73+
sizeof(_Tp) <= sizeof(unsigned long),
74+
int> = 0 >
75+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __popcount(_Tp __t) _NOEXCEPT {
76+
return std::__libcpp_popcount(static_cast<unsigned long>(__t));
77+
}
78+
79+
template < class _Tp,
80+
__enable_if_t<is_unsigned<_Tp>::value && (sizeof(_Tp) > sizeof(unsigned long)) &&
81+
sizeof(_Tp) <= sizeof(unsigned long long),
82+
int> = 0 >
83+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __popcount(_Tp __t) _NOEXCEPT {
84+
return std::__libcpp_popcount(static_cast<unsigned long long>(__t));
85+
}
86+
87+
# if _LIBCPP_STD_VER == 11
88+
// Recursive constexpr implementation for C++11 due to limited constexpr support
89+
template < class _Tp, __enable_if_t<is_unsigned<_Tp>::value && (sizeof(_Tp) > sizeof(unsigned long long)), int> = 0 >
90+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __popcount(_Tp __t) _NOEXCEPT {
91+
return __t != 0 ? std::__libcpp_popcount(static_cast<unsigned long long>(__t)) +
92+
std::__popcount<_Tp>(__t >> numeric_limits<unsigned long long>::digits)
93+
: 0;
94+
}
95+
96+
# else
97+
// Loop-based constexpr implementation for C++14 (and non-constexpr for C++03, 98)
98+
template < class _Tp, __enable_if_t<is_unsigned<_Tp>::value && (sizeof(_Tp) > sizeof(unsigned long long)), int> = 0 >
99+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int __popcount(_Tp __t) _NOEXCEPT {
100+
int __ret = 0;
101+
while (__t != 0) {
102+
__ret += std::__libcpp_popcount(static_cast<unsigned long long>(__t));
103+
__t >>= numeric_limits<unsigned long long>::digits;
104+
}
105+
return __ret;
106+
}
107+
108+
# endif // _LIBCPP_STD_VER == 11
109+
110+
#endif // _LIBCPP_STD_VER >= 17
111+
112+
#if _LIBCPP_STD_VER >= 20
113+
114+
template <__libcpp_unsigned_integer _Tp>
115+
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr int popcount(_Tp __t) noexcept {
116+
# if __has_builtin(__builtin_popcountg)
117+
return __builtin_popcountg(__t);
118+
# else
119+
return __popcount(__t);
120+
# endif
121+
}
122+
123+
#endif
66124

67125
_LIBCPP_END_NAMESPACE_STD
68126

‎libcxx/include/__fwd/bit_reference.h‎

Lines changed: 18 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -10,6 +10,8 @@
1010
#define _LIBCPP___FWD_BIT_REFERENCE_H
1111

1212
#include <__config>
13+
#include <__type_traits/enable_if.h>
14+
#include <__type_traits/is_unsigned.h>
1315

1416
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
1517
# pragma GCC system_header
@@ -20,6 +22,22 @@ _LIBCPP_BEGIN_NAMESPACE_STD
2022
template <class _Cp, bool _IsConst, typename _Cp::__storage_type = 0>
2123
class __bit_iterator;
2224

25+
template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
26+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __leading_mask(unsigned __shift) {
27+
return static_cast<_StorageType>(static_cast<_StorageType>(~static_cast<_StorageType>(0)) << __shift);
28+
}
29+
30+
template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
31+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __trailing_mask(unsigned __shift) {
32+
return static_cast<_StorageType>(static_cast<_StorageType>(~static_cast<_StorageType>(0)) >> __shift);
33+
}
34+
35+
template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
36+
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __middle_mask(unsigned __lshift, unsigned __rshift) {
37+
return static_cast<_StorageType>(
38+
std::__leading_mask<_StorageType>(__lshift) & std::__trailing_mask<_StorageType>(__rshift));
39+
}
40+
2341
_LIBCPP_END_NAMESPACE_STD
2442

2543
#endif // _LIBCPP___FWD_BIT_REFERENCE_H

‎libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count.pass.cpp‎

Lines changed: 27 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -15,12 +15,14 @@
1515

1616
// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-steps): -fconstexpr-steps=20000000
1717
// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-ops-limit): -fconstexpr-ops-limit=80000000
18+
// XFAIL: FROZEN-CXX03-HEADERS-FIXME
1819

1920
#include <algorithm>
2021
#include <cassert>
2122
#include <cstddef>
2223
#include <vector>
2324

25+
#include "sized_allocator.h"
2426
#include "test_macros.h"
2527
#include "test_iterators.h"
2628
#include "type_algorithms.h"
@@ -36,6 +38,29 @@ struct Test {
3638
}
3739
};
3840

41+
TEST_CONSTEXPR_CXX20 void test_bititer_with_custom_sized_types() {
42+
{
43+
using Alloc = sized_allocator<bool, std::uint8_t, std::int8_t>;
44+
std::vector<bool, Alloc> in(100, true, Alloc(1));
45+
assert(std::count(in.begin(), in.end(), true) == 100);
46+
}
47+
{
48+
using Alloc = sized_allocator<bool, std::uint16_t, std::int16_t>;
49+
std::vector<bool, Alloc> in(200, true, Alloc(1));
50+
assert(std::count(in.begin(), in.end(), true) == 200);
51+
}
52+
{
53+
using Alloc = sized_allocator<bool, std::uint32_t, std::int32_t>;
54+
std::vector<bool, Alloc> in(200, true, Alloc(1));
55+
assert(std::count(in.begin(), in.end(), true) == 200);
56+
}
57+
{
58+
using Alloc = sized_allocator<bool, std::uint64_t, std::int64_t>;
59+
std::vector<bool, Alloc> in(200, true, Alloc(1));
60+
assert(std::count(in.begin(), in.end(), true) == 200);
61+
}
62+
}
63+
3964
TEST_CONSTEXPR_CXX20 bool test() {
4065
types::for_each(types::cpp17_input_iterator_list<const int*>(), Test());
4166

@@ -51,6 +76,8 @@ TEST_CONSTEXPR_CXX20 bool test() {
5176
}
5277
}
5378

79+
test_bititer_with_custom_sized_types();
80+
5481
return true;
5582
}
5683

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