By my reading that implementation was assembled by humans, not the optimizer. Although, there's certainly nothing magical that prevents the optimizer from gene

By my reading that implementation was assembled by humans, not the optimizer. Although, there's certainly nothing magical that prevents the optimizer from generating such code. Here's something[1] I just threw together that (ab)uses constexpr to do just that. On my machine, building with: $ clang++ -std=c++14 fizzbuzz.cpp -O2 -S Gives code similar to: main: # @main .cfi_startproc # BB#0: pushq %rax .Ltmp0: .cfi_def_cfa_offset 16 movl $1, %edi movl $_ZL6output, %esi movl $413, %edx # imm = 0x19D callq write xorl %eax, %eax popq %rdx retq .Ltmp1: .size main, .Ltmp1-main .cfi_endproc .type _ZL6output,@object # @_ZL6output .section .rodata,"a",@progbits _ZL6output: .ascii "1\n2\nFizz\n4\nBuzz\nFizz\n7\n8\nFizz\nBuzz\n11\nFizz\n13\n14\nFizzBuzz\n16\n17\nFizz\n19\nBuzz\nFizz\n22\n23\nFizz\nBuzz\n26\nFizz\n28\n29\nFizzBuzz\n31\n32\nFizz\n34\nBuzz\nFizz\n37\n38\nFizz\nBuzz\n41\nFizz\n43\n44\nFizzBuzz\n46\n47\nFizz\n49\nBuzz\nFizz\n52\n53\nFizz\nBuzz\n56\nFizz\n58\n59\nFizzBuzz\n61\n62\nFizz\n64\nBuzz\nFizz\n67\n68\nFizz\nBuzz\n71\nFizz\n73\n74\nFizzBuzz\n76\n77\nFizz\n79\nBuzz\nFizz\n82\n83\nFizz\nBuzz\n86\nFizz\n88\n89\nFizzBuzz\n91\n92\nFizz\n94\nBuzz\nFizz\n97\n98\nFizz\nBuzz\n" Of course, having now written this I feel like I should retroactively fail my last interview. [1] https://gist.github.com/anonymous/7818f902a374a953b274 https://gist.github.com/anonymous/7818f902a374a953b274