State of “memset” functionality in C++ with modern compilers

Question

Context:

A while ago, I stumbled upon this 2001 DDJ article by Alexandrescu: http://www.ddj.com/cpp/184403799

It\'s about comparing various ways to initialize

Answer 1

The DDJ article acknowledges that memset is the best answer, and much faster than what he was trying to achieve:

There is something sacrosanct about C's memory manipulation functions memset, memcpy, and memcmp. They are likely to be highly optimized by the compiler vendor, to the extent that the compiler might detect calls to these functions and replace them with inline assembler instructions — this is the case with MSVC.

So, if memset works for you (ie. you are initializing with a single byte) then use it.

Whilst every millisecond may count, you should establish what percentage of your execution time is lost to setting memory. It is likely very low (1 or 2%??) given that you have useful work to do as well. Given that the optimization effort would likely have a much better rate of return elsewhere.