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Aligned allocation

To dynamically allocate storage with desired alignment, you can use the aligned_alloc function:

  1. void* storage = boost::alignment::aligned_alloc(alignment, size);

To deallocate storage allocated with the aligned_alloc function, use the aligned_free function:

  1. boost::alignment::aligned_free(storage);

Aligned allocator

For C++ allocator aware code, you can use the aligned_allocator class template for an allocator that respects over-alignment:

  1. std::vector<int128_t, boost::alignment::aligned_allocator<int128_t> > vector;

This template allows specifying minimum alignment for all dynamic allocations:

  1. std::vector<double, boost::alignment::aligned_allocator<double, 64> > vector;

Aligned allocator adaptor

To turn an allocator into an allocator that respects over-alignment, you can use the aligned_allocator_adaptor class template:

  1. boost::alignment::aligned_allocator_adaptor<First> second(first);

This template allows specifying minimum alignment for all dynamic allocations:

  1. boost::alignment::aligned_allocator_adaptor<First, 64> second(first);

Aligned deleter

For a deleter that can be paired with aligned_alloc, you can use the aligned_delete class:

  1. std::unique_ptr<double, boost::alignment::aligned_delete> pointer;

Pointer alignment

To advance a pointer to the next address with the desired alignment:

  1. void* pointer = storage;
  2. std::size_t space = size;
  3. void* result = boost::alignment::align(64, sizeof(double), pointer, space);

Querying alignment

To obtain the alignment of a given type at compie time, you can use:

  1. boost::alignment::alignment_of<int128_t>::value

If your compiler supports C++14 variable templates, you can also use:

  1. boost::alignment::alignment_of_v<int128_t>

Hinting alignment

To inform the compiler about the alignment of a pointer, you can use:


Checking alignment

To check alignment of a pointer you can use the is_aligned function:

  1. assert(boost::alignment::is_aligned(pointer, 64));