📗 -> End of Inline Assembly and Intro to I/O

[Lecture Slide Link]

🎤 Vocab

Make sure to know:

Structs and how they’re allocated
1. 1D arrays, except the elements are of different size
  Structs:
  
  Structs are like 1D arrays with properties being different sizes
  
  Field Bytes Past Beginning of struct
  x 0
  y 4
  s 5
  name 7
  d 17
  f 25
```
Typedef struct Struct_Type{
	Int x;
	Char y;
	Short s;
	Char name[10];
	Double d;
	Float f;
} Example Struct; 
```
  Link to original
Access memory
Ordering of Variables

Global Variables
- Stored in order of appearance, so the first global will have the lowest address
Arguments
- Stored in order of appearance, so the first argument will have the lowest address
Locals
- Stored in reverse order of appearance, so the least local will have the lowest address
Link to original
GCC calling conventions
- Caller Saved:
  - EAX, ECX, EDX
- Callee Saved:
  - The rest
How are functions called
- Calling:
  - push $label_to_continue
  - jmp foo
    or
  - call foo
- Returning
  - pop %eip
    or
  - ret

Field	Bytes Past Beginning of struct
x	0
y	4
s	5
name	7
d	17
f	25

movs (move string) - Moves a value

can be used to implement memcopy
“moves a string of bytes, words, or double words from one location to another”
stos (store string) - Copies
can be used for a memset instruction
“stores a value (byte, word, or double word) into a memory location, incrementing or decrementing the destination pointer (ES:DI) accordingly”