Learn_ASM/program_01_aaron.s at master · JAT117/Learn_ASM · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
.text
.global _main

main:
	@ load in a,b,c
	LDR r3, =a
	LDR r3,[r3]
	LDR r4, =b
	LDR r4, [r4]
	LDR r5, =c
	LDR r5, [r5]

	CMP r3, r4 @compare a and b
	BGE  a_greater_b
	BLT  b_greater_a
	B error

	a_greater_b:
	CMP r3,r5  @compare a and c
	BGE a_greater_all
	BLT c_greater_all
	B error

	b_greater_a:
	CMP r4, r5  @compare c and b
	BGE b_greater_all
	BLT c_greater_all
	B error

	a_greater_all:
	LDR r1, =MessageA @load MessageA
	B EXIT

	b_greater_all: @ load MessageB
	LDR r1, =MessageB
	B EXIT

	c_greater_all: @load MessageC
	LDR r1, =MessageC
	B EXIT

	error:
	LDR r1, =MessageError @ load MessageError
	B EXIT

	EXIT:
	@ print out result
	MOV r0, #1
	SWI 0x69
	SWI 0x11

.data
	MessageA: .asciz "message_A: A > B and A > C"
	MessageB: .asciz "message_B: B > C and B > A"
	MessageC: .asciz "message_C: C > B and C > A"
	MessageError: .asciz "error"
	a:	.word 12
	b: 	.word 13
	c:	.word 115