The major compilers optimize for microarchitecture, yes. Here's the tablegen scheduling definition behind LLVM's -mtune=sifive-670 flag as an example: https://

The major compilers optimize for microarchitecture, yes. Here's the tablegen scheduling definition behind LLVM's -mtune=sifive-670 flag as an example: https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/RISCV/RISCVSchedSiFiveP600.td https://github.com/llvm/llvm-project/blob/main/llvm/lib/Targ... It's not that things won't run, but this is necessary for compilers to generate well optimized code.