Ep 081: Introduction to the Stack Pointer
Vložit
- čas přidán 24. 11. 2020
- For proper operation, applications require memory beyond that defined by the variables. This temporary memory, called the stack, is "pointed" to by a register called the stack pointer. This video presents some of the basics of stack pointer operation.
Take aways: At the completion of this lesson, each student should be able to:
• describe the operation of the stack and the stack pointer,
• describe how the assembly language instructions PUSH and POP are used, and
• explain the importance of maintaining the integrity of the stack pointer.
#stackpointer #stack #push #pop
This is literally THE BEST explaination for stack pointer. Cant believe that this qualified lecture's free.
Well, having Bruce Willis explain assembly language for sure is something not to miss!
Incredibly well explained.
Was having a hard time finding a good explanation of this.
Thank you
Glad it helped!
I haven't finished the video but I'm already loving it! Thank you!
Thank you! Lively explanation and very understandable!
he is really a good teacher.
great explanation. easy to understand
I found assembly very complex and that makes it interesting to me.
When you use this stack pointer in function be sure pop everything from the stack before returning , cause the return instruction expect the return address to be in the top of the stack .
Amazing video very helpful! Thanks for this
Glad it was helpful!
i loved the way you explained it
Thank you so much for your kind words!
Excellent video - really beyond what I expected for a YT video. Thanks very much, saved me on my final! Also...is this dude writing backwards for the camera??
good vid sir, ,so basically stack is a certain set of memory locations right... and it may or maynot have values in it. so the stack pointer points to the top of the stack...and with that u can store or remove stuff from the stack using push or pop?
Yes, it's just memory. Of course a number of mechanisms have been added by both hardware and the operating system to make it more secure, but push and pop are basically putting items on and taking items off the stack.
Thanks sir,
I have wrong idea about POP - op code, this make me correct. Btw what class is it. I would love to join.
Is the memory that the stack uses manually addressable? That is could I do sth. like `orr r4, sp` and then `str r5, [r4]`?
Is the stack-memory a system-defined thing completely separate from any heap-address-space, or can there be overlap?
Also, is the stack-pointer automatically initialized to sth. legit, or does the programmer have to care for this?
A Stack pointer is ?: 1. Last element added to the stack or 2. Previous last element added to the stack
How will I get the operand of POP ? You said "POP r1". But will stack remember the position of r1?
That's the key. The elements of the stack have no identification of where they came from. Your (assembly language) code is responsible for maintaining the correct order of pushes and pops.
how are you writeing backwords
Nope, it's all done by flipping the video in the video editor. Sorry to disappoint!
so we push the new data from top to bottom ?
It depends on how the architect designed the stack to operate. (In fact, some processors allow the programmer to decide!) From the programmer's point of view, however, you can push any registers in any order onto the stack. To restore those registers, you simply pop off in the opposite order that you pushed.