Refactor any and all

Author: winner245

libcxx/include/bitset

@@ -142,6 +142,7 @@ template <size_t N> struct hash<std::bitset<N>>;
 #  include <__cstddef/ptrdiff_t.h>
 #  include <__cstddef/size_t.h>
 #  include <__functional/hash.h>
+#  include <__functional/identity.h>
 #  include <__functional/unary_function.h>
 #  include <__type_traits/is_char_like_type.h>
 #  include <climits>
@@ -225,14 +226,20 @@ protected:
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool all() const _NOEXCEPT {
-    return std::find(__make_iter(0), __make_iter(_Size), false) == __make_iter(_Size);
+    return __scan_bits<false>(__bit_not());
   }
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT {
-    return std::find(__make_iter(0), __make_iter(_Size), true) != __make_iter(_Size);
+    return __scan_bits<true>(std::__identity());
   }
   _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT;
 
 private:
+  struct __bit_not {
+    template <class _Tp>
+    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp operator()(const _Tp& __x) const _NOEXCEPT {
+      return ~__x;
+    }
+  };
 #  ifdef _LIBCPP_CXX03_LANG
   void __init(unsigned long long __v, false_type) _NOEXCEPT;
   _LIBCPP_HIDE_FROM_ABI void __init(unsigned long long __v, true_type) _NOEXCEPT;
@@ -243,6 +250,23 @@ private:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type) const;
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type, false_type) const;
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long to_ullong(true_type, true_type) const;
+
+  template <bool _Early_return, typename _Proj>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool __scan_bits(_Proj __proj) const _NOEXCEPT {
+    size_t __n                  = _Size;
+    __const_storage_pointer __p = __first_;
+    // do middle whole words
+    for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
+      if (__proj(*__p))
+        return _Early_return;
+    // do last partial word
+    if (__n > 0) {
+      __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
+      if (__proj(*__p) & __m)
+        return _Early_return;
+    }
+    return !_Early_return;
+  }
 };
 
 template <size_t _N_words, size_t _Size>