Why use _mm_malloc? (as opposed to _aligned_malloc, alligned_alloc, or posix_memalign)

Question

There are a few options for acquiring an aligned block of memory but they\'re very similar and the issue mostly boils down to what language standard and platforms you\'re ta

Answer 1

Intel compilers support POSIX (Linux) and non-POSIX (Windows) operating systems, hence cannot rely upon either the POSIX or the Windows function. Thus, a compiler-specific but OS-agnostic solution was chosen.

C11 is a great solution but Microsoft doesn't even support C99 yet, so who knows if they will ever support C11.

Update: Unlike the C11/POSIX/Windows allocation functions, the ICC intrinsics include a deallocation function. This allows this API to use a separate heap manager from the default one. I don't know if/when it actually does that, but it can be useful to support this model.

Disclaimer: I work for Intel but have no special knowledge of these decisions, which happened long before I joined the company.