[clang] Add _MM_FROUND_TO_NEAREST_TIES_EVEN to avx512fintrin.h (PR #99691)

[Robin Charles Gilbert via cfe-commits]

robincharlesgilbert wrote:

> How can we get MSVC to add the new name too?

Regarding the Intel compiler, which is (unlike the LLVM project but like MSVC) proprietary, all such modifications are (by far) prompted by customer requests. These requests are communicated either directly to the engineers (for example, the Argonne National Laboratory makes all sorts of requests to MKL directly) or indirectly via tickets opened by the team who handles customers. Assuming that the process is similar at Microsoft, then you would need a (significant) customer of MSVC to contact them regarding adding the name.

Now, it is possible that features found in open-source projects end up being ported in MSVC. All it needs is for a (significant) customer of MSVC to request it, because for some reason this is something they saw in GCC/LLVM/etc and they want it in MSVC. But before that happens, it needs a precedent; if the name is never put anywhere, then nobody will ever request it in MSVC.

https://github.com/llvm/llvm-project/pull/99691