Fix ambiguous call in ranges::count & std::count for vector<bool>::iterator

Author: winner245

libcxx/include/__algorithm/count.h

@@ -55,18 +55,21 @@ __count_bool(__bit_iterator<_Cp, _IsConst> __first, typename _Cp::size_type __n)
   if (__first.__ctz_ != 0) {
     __storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_);
     __storage_type __dn    = std::min(__clz_f, __n);
-    __storage_type __m     = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
-    __r                    = std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+    __storage_type __m     = __middle_mask<__storage_type>(__first.__ctz_, __clz_f - __dn);
+    // __r                    = std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+    __r = std::popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_) & __m));
     __n -= __dn;
     ++__first.__seg_;
   }
   // do middle whole words
   for (; __n >= __bits_per_word; ++__first.__seg_, __n -= __bits_per_word)
-    __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_));
+    // __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_));
+    __r += std::popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_)));
   // do last partial word
   if (__n > 0) {
-    __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
-    __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+    __storage_type __m = __trailing_mask<__storage_type>(__bits_per_word - __n);
+    // __r += std::__libcpp_popcount(std::__invert_if<!_ToCount>(*__first.__seg_) & __m);
+    __r += std::popcount(__storage_type(std::__invert_if<!_ToCount>(*__first.__seg_) & __m));
   }
   return __r;
 }

libcxx/include/__bit/popcount.h

@@ -15,6 +15,8 @@
 #include <__bit/rotate.h>
 #include <__concepts/arithmetic.h>
 #include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_unsigned.h>
 #include <limits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -62,6 +64,50 @@ template <__libcpp_unsigned_integer _Tp>
 #  endif // __has_builtin(__builtin_popcountg)
 }
 
+#else
+
+template <class _Tp, __enable_if_t<__has_builtin(__builtin_popcountg) && is_unsigned<_Tp>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int popcount(_Tp __t) _NOEXCEPT {
+  return __builtin_popcountg(__t);
+}
+
+template <
+    class _Tp,
+    __enable_if_t<!__has_builtin(__builtin_popcountg) && is_unsigned<_Tp>::value && sizeof(_Tp) <= sizeof(unsigned int),
+                  int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int popcount(_Tp __t) _NOEXCEPT {
+  return std::__libcpp_popcount(static_cast<unsigned int>(__t));
+}
+
+template < class _Tp,
+           __enable_if_t<!__has_builtin(__builtin_popcountg) && is_unsigned<_Tp>::value &&
+                             (sizeof(_Tp) > sizeof(unsigned int)) && sizeof(_Tp) <= sizeof(unsigned long),
+                         int> = 0 >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int popcount(_Tp __t) _NOEXCEPT {
+  return std::__libcpp_popcount(static_cast<unsigned long>(__t));
+}
+
+template < class _Tp,
+           __enable_if_t<!__has_builtin(__builtin_popcountg) && is_unsigned<_Tp>::value &&
+                             (sizeof(_Tp) > sizeof(unsigned long)) && sizeof(_Tp) <= sizeof(unsigned long long),
+                         int> = 0 >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int popcount(_Tp __t) _NOEXCEPT {
+  return std::__libcpp_popcount(static_cast<unsigned long long>(__t));
+}
+
+template < class _Tp,
+           __enable_if_t<!__has_builtin(__builtin_popcountg) && is_unsigned<_Tp>::value &&
+                             (sizeof(_Tp) > sizeof(unsigned long long)),
+                         int> = 0 >
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int popcount(_Tp __t) _NOEXCEPT {
+  int __ret = 0;
+  while (__t != 0) {
+    __ret += std::__libcpp_popcount(static_cast<unsigned long long>(__t));
+    __t >>= numeric_limits<unsigned long long>::digits;
+  }
+  return __ret;
+}
+
 #endif // _LIBCPP_STD_VER >= 20
 
 _LIBCPP_END_NAMESPACE_STD

libcxx/include/__fwd/bit_reference.h

@@ -10,6 +10,8 @@
 #define _LIBCPP___FWD_BIT_REFERENCE_H
 
 #include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_unsigned.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
@@ -20,6 +22,22 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 template <class _Cp, bool _IsConst, typename _Cp::__storage_type = 0>
 class __bit_iterator;
 
+template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __leading_mask(unsigned __shift) {
+  return static_cast<_StorageType>(static_cast<_StorageType>(~static_cast<_StorageType>(0)) << __shift);
+}
+
+template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __trailing_mask(unsigned __shift) {
+  return static_cast<_StorageType>(static_cast<_StorageType>(~static_cast<_StorageType>(0)) >> __shift);
+}
+
+template <class _StorageType, __enable_if_t<is_unsigned<_StorageType>::value, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _StorageType __middle_mask(unsigned __lshift, unsigned __rshift) {
+  return static_cast<_StorageType>(
+      std::__leading_mask<_StorageType>(__lshift) & std::__trailing_mask<_StorageType>(__rshift));
+}
+
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___FWD_BIT_REFERENCE_H

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

@@ -21,6 +21,7 @@
 #include <cstddef>
 #include <vector>
 
+#include "sized_allocator.h"
 #include "test_macros.h"
 #include "test_iterators.h"
 #include "type_algorithms.h"
@@ -36,6 +37,29 @@ struct Test {
   }
 };
 
+TEST_CONSTEXPR_CXX20 void test_bititer_with_custom_sized_types() {
+  {
+    using Alloc = sized_allocator<bool, std::uint8_t, std::int8_t>;
+    std::vector<bool, Alloc> in(100, true, Alloc(1));
+    assert(std::count(in.begin(), in.end(), true) == 100);
+  }
+  {
+    using Alloc = sized_allocator<bool, std::uint16_t, std::int16_t>;
+    std::vector<bool, Alloc> in(200, true, Alloc(1));
+    assert(std::count(in.begin(), in.end(), true) == 200);
+  }
+  {
+    using Alloc = sized_allocator<bool, std::uint32_t, std::int32_t>;
+    std::vector<bool, Alloc> in(200, true, Alloc(1));
+    assert(std::count(in.begin(), in.end(), true) == 200);
+  }
+  {
+    using Alloc = sized_allocator<bool, std::uint64_t, std::int64_t>;
+    std::vector<bool, Alloc> in(200, true, Alloc(1));
+    assert(std::count(in.begin(), in.end(), true) == 200);
+  }
+}
+
 TEST_CONSTEXPR_CXX20 bool test() {
   types::for_each(types::cpp17_input_iterator_list<const int*>(), Test());
 
@@ -51,6 +75,8 @@ TEST_CONSTEXPR_CXX20 bool test() {
     }
   }
 
+  test_bititer_with_custom_sized_types();
+
   return true;
 }