1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * memscan.S: Optimized memscan for the Sparc.
  4 *
  5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  6 */
  7
  8#include <asm/export.h>
  9
 10/* In essence, this is just a fancy strlen. */
 11
 12#define LO_MAGIC 0x01010101
 13#define HI_MAGIC 0x80808080
 14
 15	.text
 16	.align	4
 17	.globl	__memscan_zero, __memscan_generic
 18	.globl	memscan
 19EXPORT_SYMBOL(__memscan_zero)
 20EXPORT_SYMBOL(__memscan_generic)
 21__memscan_zero:
 22	/* %o0 = addr, %o1 = size */
 23	cmp	%o1, 0
 24	bne,a	1f
 25	 andcc	%o0, 3, %g0
 26
 27	retl
 28	 nop
 29
 301:
 31	be	mzero_scan_word
 32	 sethi	%hi(HI_MAGIC), %g2
 33
 34	ldsb	[%o0], %g3
 35mzero_still_not_word_aligned:
 36	cmp	%g3, 0
 37	bne	1f
 38	 add	%o0, 1, %o0
 39
 40	retl
 41	 sub	%o0, 1, %o0
 42
 431:
 44	subcc	%o1, 1, %o1
 45	bne,a	1f
 46	 andcc	%o0, 3, %g0
 47
 48	retl
 49	 nop
 50
 511:
 52	bne,a	mzero_still_not_word_aligned
 53	 ldsb	[%o0], %g3
 54
 55	sethi	%hi(HI_MAGIC), %g2
 56mzero_scan_word:
 57	or	%g2, %lo(HI_MAGIC), %o3
 58	sethi	%hi(LO_MAGIC), %g3
 59	or	%g3, %lo(LO_MAGIC), %o2
 60mzero_next_word:
 61	ld	[%o0], %g2
 62mzero_next_word_preloaded:
 63	sub	%g2, %o2, %g2
 64mzero_next_word_preloaded_next:
 65	andcc	%g2, %o3, %g0
 66	bne	mzero_byte_zero
 67	 add	%o0, 4, %o0
 68
 69mzero_check_out_of_fuel:
 70	subcc	%o1, 4, %o1
 71	bg,a	1f
 72	 ld	[%o0], %g2
 73
 74	retl
 75	 nop
 76
 771:
 78	b	mzero_next_word_preloaded_next
 79	 sub	%g2, %o2, %g2
 80
 81	/* Check every byte. */
 82mzero_byte_zero:
 83	ldsb	[%o0 - 4], %g2
 84	cmp	%g2, 0
 85	bne	mzero_byte_one
 86	 sub	%o0, 4, %g3
 87
 88	retl
 89	 mov	%g3, %o0
 90
 91mzero_byte_one:
 92	ldsb	[%o0 - 3], %g2
 93	cmp	%g2, 0
 94	bne,a	mzero_byte_two_and_three
 95	 ldsb	[%o0 - 2], %g2
 96
 97	retl
 98	 sub	%o0, 3, %o0
 99
100mzero_byte_two_and_three:
101	cmp	%g2, 0
102	bne,a	1f
103	 ldsb	[%o0 - 1], %g2
104
105	retl
106	 sub	%o0, 2, %o0
107
1081:
109	cmp	%g2, 0
110	bne,a	mzero_next_word_preloaded
111	 ld	[%o0], %g2
112
113	retl
114	 sub	%o0, 1, %o0
115
116mzero_found_it:
117	retl
118	 sub	%o0, 2, %o0
119
120memscan:
121__memscan_generic:
122	/* %o0 = addr, %o1 = c, %o2 = size */
123	cmp	%o2, 0
124	bne,a	0f
125	 ldub	[%o0], %g2
126
127	b,a	2f
1281:
129	ldub	[%o0], %g2
1300:
131	cmp	%g2, %o1
132	be	2f
133	 addcc	%o2, -1, %o2
134	bne	1b
135	 add	%o0, 1, %o0
1362:
137	retl
138	 nop

 
  1/*
  2 * memscan.S: Optimized memscan for the Sparc.
  3 *
  4 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  5 */
  6
 
 
  7/* In essence, this is just a fancy strlen. */
  8
  9#define LO_MAGIC 0x01010101
 10#define HI_MAGIC 0x80808080
 11
 12	.text
 13	.align	4
 14	.globl	__memscan_zero, __memscan_generic
 15	.globl	memscan
 
 
 16__memscan_zero:
 17	/* %o0 = addr, %o1 = size */
 18	cmp	%o1, 0
 19	bne,a	1f
 20	 andcc	%o0, 3, %g0
 21
 22	retl
 23	 nop
 24
 251:
 26	be	mzero_scan_word
 27	 sethi	%hi(HI_MAGIC), %g2
 28
 29	ldsb	[%o0], %g3
 30mzero_still_not_word_aligned:
 31	cmp	%g3, 0
 32	bne	1f
 33	 add	%o0, 1, %o0
 34
 35	retl
 36	 sub	%o0, 1, %o0
 37
 381:
 39	subcc	%o1, 1, %o1
 40	bne,a	1f
 41	 andcc	%o0, 3, %g0
 42
 43	retl
 44	 nop
 45
 461:
 47	bne,a	mzero_still_not_word_aligned
 48	 ldsb	[%o0], %g3
 49
 50	sethi	%hi(HI_MAGIC), %g2
 51mzero_scan_word:
 52	or	%g2, %lo(HI_MAGIC), %o3
 53	sethi	%hi(LO_MAGIC), %g3
 54	or	%g3, %lo(LO_MAGIC), %o2
 55mzero_next_word:
 56	ld	[%o0], %g2
 57mzero_next_word_preloaded:
 58	sub	%g2, %o2, %g2
 59mzero_next_word_preloaded_next:
 60	andcc	%g2, %o3, %g0
 61	bne	mzero_byte_zero
 62	 add	%o0, 4, %o0
 63
 64mzero_check_out_of_fuel:
 65	subcc	%o1, 4, %o1
 66	bg,a	1f
 67	 ld	[%o0], %g2
 68
 69	retl
 70	 nop
 71
 721:
 73	b	mzero_next_word_preloaded_next
 74	 sub	%g2, %o2, %g2
 75
 76	/* Check every byte. */
 77mzero_byte_zero:
 78	ldsb	[%o0 - 4], %g2
 79	cmp	%g2, 0
 80	bne	mzero_byte_one
 81	 sub	%o0, 4, %g3
 82
 83	retl
 84	 mov	%g3, %o0
 85
 86mzero_byte_one:
 87	ldsb	[%o0 - 3], %g2
 88	cmp	%g2, 0
 89	bne,a	mzero_byte_two_and_three
 90	 ldsb	[%o0 - 2], %g2
 91
 92	retl
 93	 sub	%o0, 3, %o0
 94
 95mzero_byte_two_and_three:
 96	cmp	%g2, 0
 97	bne,a	1f
 98	 ldsb	[%o0 - 1], %g2
 99
100	retl
101	 sub	%o0, 2, %o0
102
1031:
104	cmp	%g2, 0
105	bne,a	mzero_next_word_preloaded
106	 ld	[%o0], %g2
107
108	retl
109	 sub	%o0, 1, %o0
110
111mzero_found_it:
112	retl
113	 sub	%o0, 2, %o0
114
115memscan:
116__memscan_generic:
117	/* %o0 = addr, %o1 = c, %o2 = size */
118	cmp	%o2, 0
119	bne,a	0f
120	 ldub	[%o0], %g2
121
122	b,a	2f
1231:
124	ldub	[%o0], %g2
1250:
126	cmp	%g2, %o1
127	be	2f
128	 addcc	%o2, -1, %o2
129	bne	1b
130	 add	%o0, 1, %o0
1312:
132	retl
133	 nop