On some RISC architectures, the instruction sequences introduced in previous sections are used to push and pop. However, most CISC architectures have specific instructions to perform those operations.
In i386 instructions, the following instructions can be used to push the value of eax:
And the matching pop instruction is as follows:
Besides the number of instructions, there is a minor but sometimes significant difference between the RISC and CISC approaches. Because the RISC instruction sequences involve the use of addl and subl, the flags are affected as a side effect.
The push and pop instructions are quite special. They accept all types of operands, including immediate and all memory operands.