1	CODE32
2
3	EXPORT	|CrcUpdateT4@16|
4
5	AREA	|.text|, CODE, ARM
6
7	MACRO
8	CRC32_STEP_1
9
10	ldrb    r4, [r1], #1
11	subs    r2, r2, #1
12	eor     r4, r4, r0
13	and     r4, r4, #0xFF
14	ldr     r4, [r3, +r4, lsl #2]
15	eor     r0, r4, r0, lsr #8
16
17	MEND
18
19
20	MACRO
21	CRC32_STEP_4 $STREAM_WORD
22
23	eor     r7, r7, r8
24	eor     r7, r7, r9
25	eor     r0, r0, r7
26	eor     r0, r0, $STREAM_WORD
27	ldr     $STREAM_WORD, [r1], #4
28
29	and     r7, r0, #0xFF
30	and     r8, r0, #0xFF00
31	and     r9, r0, #0xFF0000
32	and     r0, r0, #0xFF000000
33
34	ldr     r7, [r6, +r7, lsl #2]
35	ldr     r8, [r5, +r8, lsr #6]
36	ldr     r9, [r4, +r9, lsr #14]
37	ldr     r0, [r3, +r0, lsr #22]
38
39	MEND
40
41
42|CrcUpdateT4@16| PROC
43
44	stmdb   sp!, {r4-r11, lr}
45	cmp     r2, #0
46	beq     |$fin|
47
48|$v1|
49	tst     r1, #7
50	beq     |$v2|
51	CRC32_STEP_1
52	bne     |$v1|
53
54|$v2|
55	cmp     r2, #16
56	blo     |$v3|
57
58	ldr     r10, [r1], #4
59	ldr     r11, [r1], #4
60
61	add     r4, r3, #0x400
62	add     r5, r3, #0x800
63	add     r6, r3, #0xC00
64
65	mov     r7, #0
66	mov     r8, #0
67	mov     r9, #0
68
69	sub     r2, r2, #16
70
71|$loop|
72	; pld     [r1, #0x40]
73
74	CRC32_STEP_4 r10
75	CRC32_STEP_4 r11
76
77	subs    r2, r2, #8
78	bhs     |$loop|
79
80	sub     r1, r1, #8
81	add     r2, r2, #16
82
83	eor     r7, r7, r8
84	eor     r7, r7, r9
85	eor     r0, r0, r7
86
87|$v3|
88	cmp     r2, #0
89	beq     |$fin|
90
91|$v4|
92	CRC32_STEP_1
93	bne     |$v4|
94
95|$fin|
96	ldmia   sp!, {r4-r11, pc}
97
98|CrcUpdateT4@16| ENDP
99
100	END
101