Wow, is that true? And the documentation is thousands of pages! I can't understand how Intel keep these processors consistent during development. It must be a really, really hard job.
It was a nice period in history when proper RISC was working well, when we could get stuff to run faster, but getting more transistors was expensive. Now we can't get it to run faster but we can get billions of transistors, making stuff more complicated being the way to more performance.
I wonder if we ever again will get a time where simplification is a valid option...
Notably things like undocumented opcodes, processor modes, undocumented registers, undocumented bits within registers, etc. It's not uncommon to release a specific set of documentation to trusted partners only. Back in the day intel called these "gold books".
It was a nice period in history when proper RISC was working well, when we could get stuff to run faster, but getting more transistors was expensive. Now we can't get it to run faster but we can get billions of transistors, making stuff more complicated being the way to more performance.
I wonder if we ever again will get a time where simplification is a valid option...