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
62
63
64
65
66
67
68
69
70
71
72
73
74
|
/* SPDX-License-Identifier: ISC OR GPL-2.0-only */
/*
* ldivmod.S: signed 64 bit division (quotient and remainder)
*
* Taken from CrOS EC: third_party/libaeabi-cortexm0/core/cortex-m0/ldivmod.S
*/
#include <arch/asm.h>
@ {long long quotient, long long remainder}
@ __aeabi_ldivmod(long long numerator, long long denominator)
@
@ Divide r1:r0 by r3:r2 and return the quotient in r1:r0 and the remainder in
@ r3:r2 (all signed)
@
ENTRY(__aeabi_ldivmod)
cmp r1, #0
bge L_num_pos
push {r4, lr}
movs r4, #0 @ num = -num
rsbs r0, r0, #0
sbcs r4, r1
mov r1, r4
cmp r3, #0
bge L_neg_both
movs r4, #0 @ den = -den
rsbs r2, r2, #0
sbcs r4, r3
mov r3, r4
bl __aeabi_uldivmod
movs r4, #0 @ rem = -rem
rsbs r2, r2, #0
sbcs r4, r3
mov r3, r4
pop {r4, pc}
L_neg_both:
bl __aeabi_uldivmod
movs r4, #0 @ quot = -quot
rsbs r0, r0, #0
sbcs r4, r1
mov r1, r4
movs r4, #0 @ rem = -rem
rsbs r2, r2, #0
sbcs r4, r3
mov r3, r4
pop {r4, pc}
L_num_pos:
cmp r3, #0
blt L_den_neg
push {r4, lr}
bl __aeabi_uldivmod @ offset too big for b / bge
pop {r4, pc}
L_den_neg:
push {r4, lr}
movs r4, #0 @ den = -den
rsbs r2, r2, #0
sbcs r4, r3
mov r3, r4
bl __aeabi_uldivmod
movs r4, #0 @ quot = -quot
rsbs r0, r0, #0
sbcs r4, r1
mov r1, r4
pop {r4, pc}
|
