Mastering Reverse Engineering

Emulation

The beauty of emulation is that it can fool the operating system into thinking that it is running on a certain CPU architecture. The drawback is noticeably slow performance, since almost every instruction is interpreted. To explain CPUs briefly, there are two CPU architecture designs: Complex Instruction Set Computing (CISC) and Reduced Instruction Set Computing (RISC). In assembly programming, CISC would only require a few instructions. For example, a single arithmetic instruction, such as MUL, executes lower-level instructions in it. In RISC, a low-level program should be carefully optimized. In effect, CISC has the advantage of requiring less memory space, but a single instruction would require more time to execute. On the other ...