Root/arch/sh/lib64/sdivsi3.S

Source at commit 0de2b2b3be81048189a32f7a3d3ba0ba9ec817b6 created 11 years 11 months ago.
By Maarten ter Huurne, MIPS: JZ4740: Fixed value for round robin constant.
1    .global __sdivsi3
2    .global __sdivsi3_1
3    .global __sdivsi3_2
4    .section .text..SHmedia32,"ax"
5    .align 2
6
7    /* inputs: r4,r5 */
8    /* clobbered: r1,r18,r19,r20,r21,r25,tr0 */
9    /* result in r0 */
10__sdivsi3:
11__sdivsi3_1:
12    ptb __div_table,tr0
13    gettr tr0,r20
14
15__sdivsi3_2:
16    nsb r5, r1
17    shlld r5, r1, r25 /* normalize; [-2 ..1, 1..2) in s2.62 */
18    shari r25, 58, r21 /* extract 5(6) bit index (s2.4 with hole -1..1) */
19    /* bubble */
20    ldx.ub r20, r21, r19 /* u0.8 */
21    shari r25, 32, r25 /* normalize to s2.30 */
22    shlli r21, 1, r21
23    muls.l r25, r19, r19 /* s2.38 */
24    ldx.w r20, r21, r21 /* s2.14 */
25    ptabs r18, tr0
26    shari r19, 24, r19 /* truncate to s2.14 */
27    sub r21, r19, r19 /* some 11 bit inverse in s1.14 */
28    muls.l r19, r19, r21 /* u0.28 */
29    sub r63, r1, r1
30    addi r1, 92, r1
31    muls.l r25, r21, r18 /* s2.58 */
32    shlli r19, 45, r19 /* multiply by two and convert to s2.58 */
33    /* bubble */
34    sub r19, r18, r18
35    shari r18, 28, r18 /* some 22 bit inverse in s1.30 */
36    muls.l r18, r25, r0 /* s2.60 */
37    muls.l r18, r4, r25 /* s32.30 */
38    /* bubble */
39    shari r0, 16, r19 /* s-16.44 */
40    muls.l r19, r18, r19 /* s-16.74 */
41    shari r25, 63, r0
42    shari r4, 14, r18 /* s19.-14 */
43    shari r19, 30, r19 /* s-16.44 */
44    muls.l r19, r18, r19 /* s15.30 */
45    xor r21, r0, r21 /* You could also use the constant 1 << 27. */
46    add r21, r25, r21
47    sub r21, r19, r21
48    shard r21, r1, r21
49    sub r21, r0, r0
50    blink tr0, r63
51    
52/* This table has been generated by divtab.c .
53Defects for bias -330:
54   Max defect: 6.081536e-07 at -1.000000e+00
55   Min defect: 2.849516e-08 at 1.030651e+00
56   Max 2nd step defect: 9.606539e-12 at -1.000000e+00
57   Min 2nd step defect: 0.000000e+00 at 0.000000e+00
58   Defect at 1: 1.238659e-07
59   Defect at -2: 1.061708e-07 */
60
61    .balign 2
62    .type __div_table,@object
63    .size __div_table,128
64/* negative division constants */
65    .word -16638
66    .word -17135
67    .word -17737
68    .word -18433
69    .word -19103
70    .word -19751
71    .word -20583
72    .word -21383
73    .word -22343
74    .word -23353
75    .word -24407
76    .word -25582
77    .word -26863
78    .word -28382
79    .word -29965
80    .word -31800
81/* negative division factors */
82    .byte 66
83    .byte 70
84    .byte 75
85    .byte 81
86    .byte 87
87    .byte 93
88    .byte 101
89    .byte 109
90    .byte 119
91    .byte 130
92    .byte 142
93    .byte 156
94    .byte 172
95    .byte 192
96    .byte 214
97    .byte 241
98    .skip 16
99    .global __div_table
100__div_table:
101    .skip 16
102/* positive division factors */
103    .byte 241
104    .byte 214
105    .byte 192
106    .byte 172
107    .byte 156
108    .byte 142
109    .byte 130
110    .byte 119
111    .byte 109
112    .byte 101
113    .byte 93
114    .byte 87
115    .byte 81
116    .byte 75
117    .byte 70
118    .byte 66
119/* positive division constants */
120    .word 31801
121    .word 29966
122    .word 28383
123    .word 26864
124    .word 25583
125    .word 24408
126    .word 23354
127    .word 22344
128    .word 21384
129    .word 20584
130    .word 19752
131    .word 19104
132    .word 18434
133    .word 17738
134    .word 17136
135    .word 16639
136

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