How do I build tensorflow so it is optimised for build machine?

If I build tensorflow, will it be optimised for that host?

The command i am using is… bazel build —config=opt //tensor flow/tools/pip_package

Will it be optimised? Will it use the host’s full instruction set where it can? Will it avoid instructions the host does not support?

If this is the case. How is the formal release built? Does it override the default settings or is it built on a specified host?

I ask as the formal release uses instructions my host does not have. I am building and using in the same host. I’ve read up on why this has happened. Just not clear on trying to build for my host.