RISC vs. CISC
Remember when RISC versus CISC was the battle of the ages? Even today, Intel’s chips and the upstart battalions of ARM processors align according to this paradigm, with x86 CPUs still CISC (or complex instruction set computing), and ARM representing the vanguard of RISC (or reduced instruction set computing).
But, in practice, it’s a moot point. That’s because ever since the Pentium Pro (and indeed AMD’s K5), x86 processors have really been RISC chips internally, and have relied upon a microcode translation layer to handle the x86 CISC instruction set. What’s more, over time, x86 coding has coalesced around a relatively small number of commonly used instructions. All of which means that the old divides that saw x86 chips require relatively complex compilers, along with complex instruction scheduling and decoding hardware, and thus a higher transistor count for a given theoretical performance capability, not to mention limitations on instruction pipelining, no longer fully apply. CISC architectures, such as ARM, have likewise become more complex, with support for floating point math, virtualization, and hardware cryptography. In short, RISC versus CISC is no longer the crucial question.
Winner: It simply doesn’t matter