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
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
.global __sdivsi3
.global __sdivsi3_1
.global __sdivsi3_2
.section .text..SHmedia32,"ax"
.align 2
/* inputs: r4,r5 */
/* clobbered: r1,r18,r19,r20,r21,r25,tr0 */
/* result in r0 */
__sdivsi3:
__sdivsi3_1:
ptb __div_table,tr0
gettr tr0,r20
__sdivsi3_2:
nsb r5, r1
shlld r5, r1, r25 /* normalize; [-2 ..1, 1..2) in s2.62 */
shari r25, 58, r21 /* extract 5(6) bit index (s2.4 with hole -1..1) */
/* bubble */
ldx.ub r20, r21, r19 /* u0.8 */
shari r25, 32, r25 /* normalize to s2.30 */
shlli r21, 1, r21
muls.l r25, r19, r19 /* s2.38 */
ldx.w r20, r21, r21 /* s2.14 */
ptabs r18, tr0
shari r19, 24, r19 /* truncate to s2.14 */
sub r21, r19, r19 /* some 11 bit inverse in s1.14 */
muls.l r19, r19, r21 /* u0.28 */
sub r63, r1, r1
addi r1, 92, r1
muls.l r25, r21, r18 /* s2.58 */
shlli r19, 45, r19 /* multiply by two and convert to s2.58 */
/* bubble */
sub r19, r18, r18
shari r18, 28, r18 /* some 22 bit inverse in s1.30 */
muls.l r18, r25, r0 /* s2.60 */
muls.l r18, r4, r25 /* s32.30 */
/* bubble */
shari r0, 16, r19 /* s-16.44 */
muls.l r19, r18, r19 /* s-16.74 */
shari r25, 63, r0
shari r4, 14, r18 /* s19.-14 */
shari r19, 30, r19 /* s-16.44 */
muls.l r19, r18, r19 /* s15.30 */
xor r21, r0, r21 /* You could also use the constant 1 << 27. */
add r21, r25, r21
sub r21, r19, r21
shard r21, r1, r21
sub r21, r0, r0
blink tr0, r63
/* This table has been generated by divtab.c .
Defects for bias -330:
Max defect: 6.081536e-07 at -1.000000e+00
Min defect: 2.849516e-08 at 1.030651e+00
Max 2nd step defect: 9.606539e-12 at -1.000000e+00
Min 2nd step defect: 0.000000e+00 at 0.000000e+00
Defect at 1: 1.238659e-07
Defect at -2: 1.061708e-07 */
.balign 2
.type __div_table,@object
.size __div_table,128
/* negative division constants */
.word -16638
.word -17135
.word -17737
.word -18433
.word -19103
.word -19751
.word -20583
.word -21383
.word -22343
.word -23353
.word -24407
.word -25582
.word -26863
.word -28382
.word -29965
.word -31800
/* negative division factors */
.byte 66
.byte 70
.byte 75
.byte 81
.byte 87
.byte 93
.byte 101
.byte 109
.byte 119
.byte 130
.byte 142
.byte 156
.byte 172
.byte 192
.byte 214
.byte 241
.skip 16
.global __div_table
__div_table:
.skip 16
/* positive division factors */
.byte 241
.byte 214
.byte 192
.byte 172
.byte 156
.byte 142
.byte 130
.byte 119
.byte 109
.byte 101
.byte 93
.byte 87
.byte 81
.byte 75
.byte 70
.byte 66
/* positive division constants */
.word 31801
.word 29966
.word 28383
.word 26864
.word 25583
.word 24408
.word 23354
.word 22344
.word 21384
.word 20584
.word 19752
.word 19104
.word 18434
.word 17738
.word 17136
.word 16639
|
