The autovectorizer can, at times, when you check it produce reasonable simd code with a given compiler based on simple, clear C code. Is gcc as good in this cas

The autovectorizer can, at times, when you check it produce reasonable simd code with a given compiler based on simple, clear C code. Is gcc as good in this case? Are previous versions of clang (that may be employed by users) going to work out as well. How do you check in your build that the compiler did the right thing? If you touch the C code in any way will it silently do something you don't want? Autovectorization is great and improving.