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std::assume_aligned(3)	       C++ Standard Libary	  std::assume_aligned(3)

NAME
     std::assume_aligned - std::assume_aligned

Synopsis
	Defined in header <memory>
	template< std::size_t N, class T >		      (since C++20)
	[[nodiscard]] constexpr T* assume_aligned( T* ptr );

	Informs  the  implementation that the object ptr points to is aligned to
     at least N.
	The implementation may use this information to generate  more  efficient
     code, but it
	might only make this assumption if the object is accessed via the return
     value of
	assume_aligned.

	N  must be a power of 2. The behavior is undefined if ptr does not point
     to an object
	of type T (ignoring cv-qualification at every level), or if the object's
     alignment
	is not at least N.

Return value
	ptr.

Exceptions
	Throws nothing.

Notes
	To ensure that the program benefits from the optimizations enabled by
	assume_aligned, it is important to access  the	object	via  its  return
     value:

      void f(int* p)
      {
	  int* p1 = std::assume_aligned<256>(p);
	  // Use p1, not p, to ensure benefit from the alignment assumption.
	  // However, the program has undefined behavior if p is not aligned
	  // regardless of whether p1 is used.
      }

	It is up to the program to ensure that the alignment assumption actually
     holds. A
	call  to assume_aligned does not cause the compiler to verify or enforce
     this.

	   Feature-test macro	  Value    Std	       Feature
	__cpp_lib_assume_aligned 201811L (C++20) std::assume_aligned

Example
	 This section is incomplete
	 Reason: no example

See also
	alignof operator(C++11)       queries alignment requirements of a type
	alignas specifier(C++11)      specifies that the storage for  the  vari-
     able should be
				      aligned by specific amount
	aligned_storage 	       defines	the  type  suitable  for  use as
     uninitialized
	(C++11)(deprecated in C++23)  storage for types of given size
				      (class template)
	align			      aligns a pointer in a buffer
	(C++11) 		      (function)
				      specifies that the expression will  always
     evaluate to
	[[assume(expression)]](C++23) true at a given point
				      (attribute specifier)

Category:
	  * Todo no example

http://cppreference.com 	   2024.06.10		  std::assume_aligned(3)
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