assembly - pushl/popl %esp 的汇编级表示是什么？

Question

C++

ATT组装

我试图了解以下两条指令的行为:

pushl %esp

和:

popl %esp

请注意，他们将计算出的值存储回 %esp .

我正在独立考虑这些说明，而不是按顺序考虑。我知道存储在 %esp 中的值始终是增量/减量之前的值，但我如何用汇编语言表示行为？这是我到目前为止想出的:

对于推送:

movl %esp, %edx     1. save value of %esp
subl  $4, %esp      2. decrement stack pointer
movl %edx, (%esp)   3. store old value of %esp on top of stack

对于流行:

movl (%esp), %esp   You wouldn’t need the increment portion. 

这样对吗？如果没有，我哪里出错了？谢谢。

Answer 1

正如它所说的push esp在 Intel® 64 and IA-32 Architectures Developer's Manual: Combined Volumes :

The PUSH ESP instruction pushes the value of the ESP register as it existed
before the instruction was executed. If a PUSH instruction uses a memory operand
in which the ESP register is used for computing the operand address, the address
of the operand is computed before the ESP register is decremented.

至于 pop esp :

The POP ESP instruction increments the stack pointer (ESP) before data at the old
top of stack is written into the destination.