137 строки
2.7 KiB
ArmAsm
137 строки
2.7 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
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.global __sdivsi3
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.global __sdivsi3_1
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.global __sdivsi3_2
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.section .text..SHmedia32,"ax"
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.align 2
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/* inputs: r4,r5 */
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/* clobbered: r1,r18,r19,r20,r21,r25,tr0 */
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/* result in r0 */
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__sdivsi3:
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__sdivsi3_1:
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ptb __div_table,tr0
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gettr tr0,r20
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__sdivsi3_2:
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nsb r5, r1
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shlld r5, r1, r25 /* normalize; [-2 ..1, 1..2) in s2.62 */
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shari r25, 58, r21 /* extract 5(6) bit index (s2.4 with hole -1..1) */
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/* bubble */
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ldx.ub r20, r21, r19 /* u0.8 */
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shari r25, 32, r25 /* normalize to s2.30 */
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shlli r21, 1, r21
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muls.l r25, r19, r19 /* s2.38 */
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ldx.w r20, r21, r21 /* s2.14 */
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ptabs r18, tr0
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shari r19, 24, r19 /* truncate to s2.14 */
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sub r21, r19, r19 /* some 11 bit inverse in s1.14 */
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muls.l r19, r19, r21 /* u0.28 */
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sub r63, r1, r1
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addi r1, 92, r1
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muls.l r25, r21, r18 /* s2.58 */
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shlli r19, 45, r19 /* multiply by two and convert to s2.58 */
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/* bubble */
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sub r19, r18, r18
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shari r18, 28, r18 /* some 22 bit inverse in s1.30 */
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muls.l r18, r25, r0 /* s2.60 */
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muls.l r18, r4, r25 /* s32.30 */
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/* bubble */
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shari r0, 16, r19 /* s-16.44 */
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muls.l r19, r18, r19 /* s-16.74 */
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shari r25, 63, r0
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shari r4, 14, r18 /* s19.-14 */
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shari r19, 30, r19 /* s-16.44 */
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muls.l r19, r18, r19 /* s15.30 */
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xor r21, r0, r21 /* You could also use the constant 1 << 27. */
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add r21, r25, r21
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sub r21, r19, r21
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shard r21, r1, r21
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sub r21, r0, r0
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blink tr0, r63
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/* This table has been generated by divtab.c .
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Defects for bias -330:
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Max defect: 6.081536e-07 at -1.000000e+00
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Min defect: 2.849516e-08 at 1.030651e+00
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Max 2nd step defect: 9.606539e-12 at -1.000000e+00
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Min 2nd step defect: 0.000000e+00 at 0.000000e+00
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Defect at 1: 1.238659e-07
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Defect at -2: 1.061708e-07 */
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.balign 2
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.type __div_table,@object
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.size __div_table,128
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/* negative division constants */
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.word -16638
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.word -17135
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.word -17737
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.word -18433
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.word -19103
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.word -19751
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.word -20583
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.word -21383
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.word -22343
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.word -23353
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.word -24407
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.word -25582
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.word -26863
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.word -28382
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.word -29965
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.word -31800
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/* negative division factors */
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.byte 66
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.byte 70
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.byte 75
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.byte 81
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.byte 87
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.byte 93
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.byte 101
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.byte 109
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.byte 119
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.byte 130
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.byte 142
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.byte 156
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.byte 172
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.byte 192
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.byte 214
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.byte 241
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.skip 16
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.global __div_table
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__div_table:
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.skip 16
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/* positive division factors */
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.byte 241
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.byte 214
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.byte 192
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.byte 172
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.byte 156
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.byte 142
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.byte 130
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.byte 119
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.byte 109
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.byte 101
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.byte 93
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.byte 87
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.byte 81
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.byte 75
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.byte 70
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.byte 66
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/* positive division constants */
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.word 31801
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.word 29966
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.word 28383
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.word 26864
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.word 25583
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.word 24408
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.word 23354
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.word 22344
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.word 21384
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.word 20584
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.word 19752
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.word 19104
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.word 18434
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.word 17738
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.word 17136
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.word 16639
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