x86 vs. ARM/RISC-V has fewer registers which can mean more spill/fill to the stack which results in more instructions to do the same work.
The instruction decode length for x86 has been creeping up with 64-bit encodings and SIMD extenstion (prefix bytes) as you can see it's 3.96 for x86 vs. 4.00 for ARM.
x86 vs. ARM/RISC-V has fewer registers which can mean more spill/fill to the stack which results in more instructions to do the same work.
The instruction decode length for x86 has been creeping up with 64-bit encodings and SIMD extenstion (prefix bytes) as you can see it's 3.96 for x86 vs. 4.00 for ARM.