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Good day
I see that parameters are Pushed.
But then Call also Pushes the return / next instruction address to the stack
Since one has to Pop the return address out of the stack in order to Pop the parameters how does one read parameters and ensure that the Ret executes correctly?

Regards
Kamil

the values in stack are accessible with pointing relating to stack pointer on procedure enter - ebp (enchanced base pointer) register is pushed to stack and esp (enchansed stack pointer) value copied to ebp, ebp value usually is not altered until procedure exits and used to access to stack parameters and local variables, eg.:

mov eax,[hWnd]

in certain case can be equal to:

mov eax,[ebp + 8]

etc.

Hello, Shoorick
i think we misunderstood each other
Here is a pseudo code
; calling procedure
push Parm1 ; a parameter is pushed
call Proc1 ; call pushes Instruction Pointer onto
; stack and loads Instruction Pointer with the address of Proc1.
; Now the stack has on top the return address
; and a parameter below it
; Here is what i would do in the called procedure
.data
RetAddress dword ?
Parm1 dword ?
.code
pop RetAddress ; saving the return address
pop Parm1 ; read a parameter
; some code
push RetAddress ; push the return address back to stack
ret ; Transfers control from a procedure back to the instruction address
; saved on the stack.

That's my take
My question is , what's the common practice of returning from a called with parameters procedure?

Kamil

there are many ways to call procedure with parameters and return, they are described in "calling conventions" (look web for details).

most common under win32 is "stdcall":

when you use "proc" macro, it adds some high level-like work:

finally, instead of "mov esp,ebp/pop ebp" the "leave" command is using, which does the same. the manner of such parameters transfer through stack is calling "procedure frame".

slightly similar is creating local variables for procedure in stack, which are as temporal, as parameters.

Thank you.
I found something new to me in your reply
Procedures are just blocks of code between an identifier and a ret instruction.

call my_proc
-------
my_proc: ; identifier like a label or a var. name
push ebp
mov ebp,esp
mov eax,[ebp+8] ; reading a parameter
; some code
mov esp,ebp; esp restored as at start of proc
pop ebp; ebp restored
ret 4; return: pops return address from stack and removes 4 bytes from stack

regards
Kamil