[flagada]

> Does the whole RISC Vs CISC of X86 and ARM make a difference?

Not really. Arm hasn't been RISC for quite a while now (there's a "Floating-point Javascript Convert to Signed fixed-point, rounding toward Zero" instruction(!), SIMD, etc etc).

The difference can be explained partially by the memory model: x86 has total store ordering, which can be slower than Arm's weak memory model (it allows the hardware to be more creative).

> running native compiled code

There's more to it than 'running native code'. It depends a lot on what code is running (any CPU implementing the above javascript instruction would be much faster on a web benchmark for example). It also depends on the compiler. If the code is control-flow heavy, there isn't much to do except having large cache sizes and wide pipes, which most high-end, out-of-order CPU do already.