xref: /OK3568_Linux_fs/kernel/arch/alpha/lib/memset.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun/*
3*4882a593Smuzhiyun * linux/arch/alpha/lib/memset.S
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * This is an efficient (and small) implementation of the C library "memset()"
6*4882a593Smuzhiyun * function for the alpha.
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun *	(C) Copyright 1996 Linus Torvalds
9*4882a593Smuzhiyun *
10*4882a593Smuzhiyun * This routine is "moral-ware": you are free to use it any way you wish, and
11*4882a593Smuzhiyun * the only obligation I put on you is a moral one: if you make any improvements
12*4882a593Smuzhiyun * to the routine, please send me your improvements for me to use similarly.
13*4882a593Smuzhiyun *
14*4882a593Smuzhiyun * The scheduling comments are according to the EV5 documentation (and done by
15*4882a593Smuzhiyun * hand, so they might well be incorrect, please do tell me about it..)
16*4882a593Smuzhiyun */
17*4882a593Smuzhiyun#include <asm/export.h>
18*4882a593Smuzhiyun	.set noat
19*4882a593Smuzhiyun	.set noreorder
20*4882a593Smuzhiyun.text
21*4882a593Smuzhiyun	.globl memset
22*4882a593Smuzhiyun	.globl __memset
23*4882a593Smuzhiyun	.globl ___memset
24*4882a593Smuzhiyun	.globl __memset16
25*4882a593Smuzhiyun	.globl __constant_c_memset
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun	.ent ___memset
28*4882a593Smuzhiyun.align 5
29*4882a593Smuzhiyun___memset:
30*4882a593Smuzhiyun	.frame $30,0,$26,0
31*4882a593Smuzhiyun	.prologue 0
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun	and $17,255,$1		/* E1 */
34*4882a593Smuzhiyun	insbl $17,1,$17		/* .. E0 */
35*4882a593Smuzhiyun	bis $17,$1,$17		/* E0 (p-c latency, next cycle) */
36*4882a593Smuzhiyun	sll $17,16,$1		/* E1 (p-c latency, next cycle) */
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun	bis $17,$1,$17		/* E0 (p-c latency, next cycle) */
39*4882a593Smuzhiyun	sll $17,32,$1		/* E1 (p-c latency, next cycle) */
40*4882a593Smuzhiyun	bis $17,$1,$17		/* E0 (p-c latency, next cycle) */
41*4882a593Smuzhiyun	ldq_u $31,0($30)	/* .. E1 */
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun.align 5
44*4882a593Smuzhiyun__constant_c_memset:
45*4882a593Smuzhiyun	addq $18,$16,$6		/* E0 */
46*4882a593Smuzhiyun	bis $16,$16,$0		/* .. E1 */
47*4882a593Smuzhiyun	xor $16,$6,$1		/* E0 */
48*4882a593Smuzhiyun	ble $18,end		/* .. E1 */
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun	bic $1,7,$1		/* E0 */
51*4882a593Smuzhiyun	beq $1,within_one_quad	/* .. E1 (note EV5 zero-latency forwarding) */
52*4882a593Smuzhiyun	and $16,7,$3		/* E0 */
53*4882a593Smuzhiyun	beq $3,aligned		/* .. E1 (note EV5 zero-latency forwarding) */
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun	ldq_u $4,0($16)		/* E0 */
56*4882a593Smuzhiyun	bis $16,$16,$5		/* .. E1 */
57*4882a593Smuzhiyun	insql $17,$16,$2	/* E0 */
58*4882a593Smuzhiyun	subq $3,8,$3		/* .. E1 */
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun	addq $18,$3,$18		/* E0	$18 is new count ($3 is negative) */
61*4882a593Smuzhiyun	mskql $4,$16,$4		/* .. E1 (and possible load stall) */
62*4882a593Smuzhiyun	subq $16,$3,$16		/* E0 	$16 is new aligned destination */
63*4882a593Smuzhiyun	bis $2,$4,$1		/* .. E1 */
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun	bis $31,$31,$31		/* E0 */
66*4882a593Smuzhiyun	ldq_u $31,0($30)	/* .. E1 */
67*4882a593Smuzhiyun	stq_u $1,0($5)		/* E0 */
68*4882a593Smuzhiyun	bis $31,$31,$31		/* .. E1 */
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun.align 4
71*4882a593Smuzhiyunaligned:
72*4882a593Smuzhiyun	sra $18,3,$3		/* E0 */
73*4882a593Smuzhiyun	and $18,7,$18		/* .. E1 */
74*4882a593Smuzhiyun	bis $16,$16,$5		/* E0 */
75*4882a593Smuzhiyun	beq $3,no_quad		/* .. E1 */
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun.align 3
78*4882a593Smuzhiyunloop:
79*4882a593Smuzhiyun	stq $17,0($5)		/* E0 */
80*4882a593Smuzhiyun	subq $3,1,$3		/* .. E1 */
81*4882a593Smuzhiyun	addq $5,8,$5		/* E0 */
82*4882a593Smuzhiyun	bne $3,loop		/* .. E1 */
83*4882a593Smuzhiyun
84*4882a593Smuzhiyunno_quad:
85*4882a593Smuzhiyun	bis $31,$31,$31		/* E0 */
86*4882a593Smuzhiyun	beq $18,end		/* .. E1 */
87*4882a593Smuzhiyun	ldq $7,0($5)		/* E0 */
88*4882a593Smuzhiyun	mskqh $7,$6,$2		/* .. E1 (and load stall) */
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun	insqh $17,$6,$4		/* E0 */
91*4882a593Smuzhiyun	bis $2,$4,$1		/* .. E1 */
92*4882a593Smuzhiyun	stq $1,0($5)		/* E0 */
93*4882a593Smuzhiyun	ret $31,($26),1		/* .. E1 */
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun.align 3
96*4882a593Smuzhiyunwithin_one_quad:
97*4882a593Smuzhiyun	ldq_u $1,0($16)		/* E0 */
98*4882a593Smuzhiyun	insql $17,$16,$2	/* E1 */
99*4882a593Smuzhiyun	mskql $1,$16,$4		/* E0 (after load stall) */
100*4882a593Smuzhiyun	bis $2,$4,$2		/* E0 */
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun	mskql $2,$6,$4		/* E0 */
103*4882a593Smuzhiyun	mskqh $1,$6,$2		/* .. E1 */
104*4882a593Smuzhiyun	bis $2,$4,$1		/* E0 */
105*4882a593Smuzhiyun	stq_u $1,0($16)		/* E0 */
106*4882a593Smuzhiyun
107*4882a593Smuzhiyunend:
108*4882a593Smuzhiyun	ret $31,($26),1		/* E1 */
109*4882a593Smuzhiyun	.end ___memset
110*4882a593SmuzhiyunEXPORT_SYMBOL(___memset)
111*4882a593SmuzhiyunEXPORT_SYMBOL(__constant_c_memset)
112*4882a593Smuzhiyun
113*4882a593Smuzhiyun	.align 5
114*4882a593Smuzhiyun	.ent __memset16
115*4882a593Smuzhiyun__memset16:
116*4882a593Smuzhiyun	.prologue 0
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun	inswl $17,0,$1		/* E0 */
119*4882a593Smuzhiyun	inswl $17,2,$2		/* E0 */
120*4882a593Smuzhiyun	inswl $17,4,$3		/* E0 */
121*4882a593Smuzhiyun	or $1,$2,$1		/* .. E1 */
122*4882a593Smuzhiyun	inswl $17,6,$4		/* E0 */
123*4882a593Smuzhiyun	or $1,$3,$1		/* .. E1 */
124*4882a593Smuzhiyun	or $1,$4,$17		/* E0 */
125*4882a593Smuzhiyun	br __constant_c_memset	/* .. E1 */
126*4882a593Smuzhiyun
127*4882a593Smuzhiyun	.end __memset16
128*4882a593SmuzhiyunEXPORT_SYMBOL(__memset16)
129*4882a593Smuzhiyun
130*4882a593Smuzhiyunmemset = ___memset
131*4882a593Smuzhiyun__memset = ___memset
132*4882a593Smuzhiyun	EXPORT_SYMBOL(memset)
133*4882a593Smuzhiyun	EXPORT_SYMBOL(__memset)
134