You program a modern x86 in almost a RISC esque way with a couple of exceptions. For instance if you're just doing a read-modify-write that can be done in one instruction, that's preferred. You can do all of the work only allocating physical register file resources without allocating any architectural registers.
Just read "Register file" on Wikipedia, thank you. Would you kindly share any link that discusses the technique you explained? This is pretty new idea to me.
