Question

I wish to know which one is responsible for cleanup of the stack

Suppose you have a function fun lets say like this:

var = fun(int x, int y, float z, char x);

when fun will get called it will go into the stack along with the parameters then when the function returns who is responsible for cleanup of the stack is it the function it self or the “var” which will hold the return value.

One more thing, can anyone explain the concepts of calling conventions?

Answer 1

calling convention refers to who is doing the cleanup of the stack; caller or callee.

Calling conventions can differ in:

• where parameters and return values are placed (in registers; on the call
  stack; a mix of both)
• the order in which parameters are passed (or parts of a single
  parameter)
• how the task of setting up and cleaning up a function call is divided
  between the caller and the callee.
• which registers that may be directly used by the callee may sometimes also
  be included

Architectures almost always have more
than one possible calling convention.