CPSC 2310 - DAY 19
OCTOBER 17, 2016

================================================================================

CALLING SCANF IN ARM
--------------------

scanf(format_string, addr-list

	^r0            ^r1, r2

ldr r0, =F873929  @Allows loading large numbers (when #2 doesn't work)

If what follows is a label, then the addr is placed in the register

must save the link register to return after scanf is called!

mov r0, #0 @return 0 if program is successful

Arrays
------

In high level languages, we have several techniques avaliable for constructing
data structures:
	.One dimensional arrays
	.Multi-dimensional arrays
	.Structs
	.Bit Sets
	.Linked lists
	.Trees

At the assembly language level, all of those approaches map onto single
dimension arrays alone.

In order to emulate one of the other structures, we must create a mapping
from the high level

The origin of the array is not always the same:
	.In C, C++ and Java, arrays start wih index 0
	.In BASIC and FORTRAN, arrays start with index 1
	

In ARM, to allocate arrays,

	.data
	.align 2
a: 	.skip 400

To reference any element in an array, we need to have both the starting