%default {"result":"%eax"}
    /*
     * Generic 32-bit "lit8" binary operation.  Provide an "instr" line
     * that specifies an instruction that performs "result = eax op ecx".
     * This could be an x86 instruction or a function call.  (If the result
     * comes back in a register other than r0, you can override "result".)
     *
     * For: add-int/lit8, rsub-int/lit8
     *      and-int/lit8, or-int/lit8, xor-int/lit8,
     *      shl-int/lit8, shr-int/lit8, ushr-int/lit8
     */
    /* binop/lit8 vAA, vBB, #+CC */
    movzbl    2(rPC),%eax              # eax<- BB
    movsbl    3(rPC),%ecx              # ecx<- ssssssCC
    GET_VREG_R   %eax %eax             # eax<- rBB
    $instr                             # ex: addl %ecx,%eax
    SET_VREG   $result rINST
    FETCH_INST_OPCODE 2 %ecx
    ADVANCE_PC 2
    GOTO_NEXT_R %ecx