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path: root/arch/sh/lib64/sdivsi3.S
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/* SPDX-License-Identifier: GPL-2.0 */
	.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