What does ebp and esp in a disassembly code mean?

Question

Below posted is my code. Help me out in understanding what the below code means:

   push    ebp
   mov     ebp, esp
   sub     esp, 230h

Related: http://stackoverflow.com/questions/20695203/behaviour-of-ebp-and-esp-in-stacks-using-function-with-parameter — nrz, Oct 31 '14 at 22:53
Possible duplicate of [why to use ebp in function prologue/epilogue?](http://stackoverflow.com/questions/15655553/why-to-use-ebp-in-function-prologue-epilogue) — Peter Cordes, Jun 23 '16 at 12:24
Related: https://stackoverflow.com/questions/21718397/what-are-the-esp-and-the-ebp-registers — riQQ, Apr 03 '23 at 10:20

score 3 · Accepted Answer · edited May 23 '17 at 12:16

It is a function prologue.

Pushes the old base pointer onto the stack, so it can be restored later:

   push    ebp

Assigns the value of stack pointer into base pointer, then a new stack frame will be created on top of the old stack frame:

   mov     ebp, esp

Moves the stack pointer further by decreasing or increasing its value (depending on whether the stack grows down or up):

   sub     esp, 230h

Here, the230h immediate value is the number of bytes reserved on the stack for local use in the function.

In a similar way, the function epilogue reverses the actions of the prologue and returns control to the calling function.

Some compilers offer the option of not using frame pointers, which frees up ebp to be used as a generic register (it would still need to be saved). — rcgldr, Nov 01 '14 at 02:17

1 Answers1