title: Are RAX, RBX, RCX, RDX, RSI, RDI, RBP, RSP, R8-R15 interchangable?
body: <p>Are x64 registers interchangable, in the sense that any instruction that works with one combination of them will work with any other? Is there performance difference or any other considerations that make them different from each other, apart from the names?</p>