One problem that's solved with assembly today is optimizing code in C or C++. In order to do that, you'd certainly need to study documentation newer than this b

One problem that's solved with assembly today is optimizing code in C or C++. In order to do that, you'd certainly need to study documentation newer than this book, because you need to know the performance characteristics of (old) instructions on current CPUs and you need to know about new instructions, like SIMD instructions. Without that knowledge, you'd be lost, because you're trying to beat the compiler, which is already pretty good. This would be a good foundation, though. Not everything has changed.