Memory Layout for Compiled Program
Operating System |
---|
User Process Code |
---|
Machine Code |
User Process Data |
---|
MaxBlock |
Stack |
: |
\:/ |
… |
/:\ |
: |
Dynamically Allocated Heap |
Global Static Data (Const,Var) |
0 |
Both dynamically allocated heap and stack expand
- heap need not be contiguous can request more memory from the OS if needed
- stack grows downwards
Heap is more general:
- can allocate, read/write, and deallocate in any order
- Garbace Collector does deallocation automatically
- More in Lecture 14
Stack is more efficient - allocation simple increment, decrement
Top of stack pointer (SP) is often a register
If stack grows towards smaller addresses:
- to allocate N bytes (push)
SP := SP - N
- to deallocate N bytes (pop)
SP := SP + N