Yes I think it's better to say this in a more limited way: certain CPU instructions such as push, pop, and call manipulate the stack pointer register in a way t

Yes I think it's better to say this in a more limited way: certain CPU instructions such as push, pop, and call manipulate the stack pointer register in a way that assumes common stack conventions. One interesting thing is that the implementation of these instructions do specify the question of whether the stack grows up or down. On x86 these instructions subtract from rsp when they want to grow the stack, ergo on x86 the stack grows down.