tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1 .global __sdivsi3
2 .section .text..SHmedia32,"ax"
3 .align 2
4
5 /* inputs: r4,r5 */
6 /* clobbered: r1,r18,r19,r20,r21,r25,tr0 */
7 /* result in r0 */
8__sdivsi3:
9 ptb __div_table,tr0
10
11 nsb r5, r1
12 shlld r5, r1, r25 /* normalize; [-2 ..1, 1..2) in s2.62 */
13 shari r25, 58, r21 /* extract 5(6) bit index (s2.4 with hole -1..1) */
14 /* bubble */
15 gettr tr0,r20
16 ldx.ub r20, r21, r19 /* u0.8 */
17 shari r25, 32, r25 /* normalize to s2.30 */
18 shlli r21, 1, r21
19 muls.l r25, r19, r19 /* s2.38 */
20 ldx.w r20, r21, r21 /* s2.14 */
21 ptabs r18, tr0
22 shari r19, 24, r19 /* truncate to s2.14 */
23 sub r21, r19, r19 /* some 11 bit inverse in s1.14 */
24 muls.l r19, r19, r21 /* u0.28 */
25 sub r63, r1, r1
26 addi r1, 92, r1
27 muls.l r25, r21, r18 /* s2.58 */
28 shlli r19, 45, r19 /* multiply by two and convert to s2.58 */
29 /* bubble */
30 sub r19, r18, r18
31 shari r18, 28, r18 /* some 22 bit inverse in s1.30 */
32 muls.l r18, r25, r0 /* s2.60 */
33 muls.l r18, r4, r25 /* s32.30 */
34 /* bubble */
35 shari r0, 16, r19 /* s-16.44 */
36 muls.l r19, r18, r19 /* s-16.74 */
37 shari r25, 63, r0
38 shari r4, 14, r18 /* s19.-14 */
39 shari r19, 30, r19 /* s-16.44 */
40 muls.l r19, r18, r19 /* s15.30 */
41 xor r21, r0, r21 /* You could also use the constant 1 << 27. */
42 add r21, r25, r21
43 sub r21, r19, r21
44 shard r21, r1, r21
45 sub r21, r0, r0
46 blink tr0, r63
47
48/* This table has been generated by divtab.c .
49Defects for bias -330:
50 Max defect: 6.081536e-07 at -1.000000e+00
51 Min defect: 2.849516e-08 at 1.030651e+00
52 Max 2nd step defect: 9.606539e-12 at -1.000000e+00
53 Min 2nd step defect: 0.000000e+00 at 0.000000e+00
54 Defect at 1: 1.238659e-07
55 Defect at -2: 1.061708e-07 */
56
57 .balign 2
58 .type __div_table,@object
59 .size __div_table,128
60/* negative division constants */
61 .word -16638
62 .word -17135
63 .word -17737
64 .word -18433
65 .word -19103
66 .word -19751
67 .word -20583
68 .word -21383
69 .word -22343
70 .word -23353
71 .word -24407
72 .word -25582
73 .word -26863
74 .word -28382
75 .word -29965
76 .word -31800
77/* negative division factors */
78 .byte 66
79 .byte 70
80 .byte 75
81 .byte 81
82 .byte 87
83 .byte 93
84 .byte 101
85 .byte 109
86 .byte 119
87 .byte 130
88 .byte 142
89 .byte 156
90 .byte 172
91 .byte 192
92 .byte 214
93 .byte 241
94 .skip 16
95 .global __div_table
96__div_table:
97 .skip 16
98/* positive division factors */
99 .byte 241
100 .byte 214
101 .byte 192
102 .byte 172
103 .byte 156
104 .byte 142
105 .byte 130
106 .byte 119
107 .byte 109
108 .byte 101
109 .byte 93
110 .byte 87
111 .byte 81
112 .byte 75
113 .byte 70
114 .byte 66
115/* positive division constants */
116 .word 31801
117 .word 29966
118 .word 28383
119 .word 26864
120 .word 25583
121 .word 24408
122 .word 23354
123 .word 22344
124 .word 21384
125 .word 20584
126 .word 19752
127 .word 19104
128 .word 18434
129 .word 17738
130 .word 17136
131 .word 16639