1/* $NetBSD: memcmp.S,v 1.3 2003/10/14 07:51:45 scw Exp $ */
2
3/*
4 * Copyright 2003 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Steve C. Woodford for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37/*
38 * Copyright (c) 2002 ARM Ltd
39 * All rights reserved.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 * notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 * notice, this list of conditions and the following disclaimer in the
48 * documentation and/or other materials provided with the distribution.
49 * 3. The name of the company may not be used to endorse or promote
50 * products derived from this software without specific prior written
51 * permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
54 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
55 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
56 * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
57 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
58 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
59 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
60 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
61 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
62 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
63 */
64
65#include <machine/asm.h>
66
| 1/* $NetBSD: memcmp.S,v 1.3 2003/10/14 07:51:45 scw Exp $ */
2
3/*
4 * Copyright 2003 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Steve C. Woodford for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37/*
38 * Copyright (c) 2002 ARM Ltd
39 * All rights reserved.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 * notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 * notice, this list of conditions and the following disclaimer in the
48 * documentation and/or other materials provided with the distribution.
49 * 3. The name of the company may not be used to endorse or promote
50 * products derived from this software without specific prior written
51 * permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
54 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
55 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
56 * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
57 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
58 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
59 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
60 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
61 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
62 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
63 */
64
65#include <machine/asm.h>
66
|
68
69ENTRY(memcmp)
70 mov ip, r0
71#if defined(_KERNEL) && !defined(_STANDALONE)
72 cmp r2, #0x06
73 beq .Lmemcmp_6bytes
74#endif
75 mov r0, #0x00
76
77 /* Are both addresses aligned the same way? */
78 cmp r2, #0x00
79 eornes r3, ip, r1
80 RETeq /* len == 0, or same addresses! */
81 tst r3, #0x03
82 subne r2, r2, #0x01
83 bne .Lmemcmp_bytewise2 /* Badly aligned. Do it the slow way */
84
85 /* Word-align the addresses, if necessary */
86 sub r3, r1, #0x05
87 ands r3, r3, #0x03
88 add r3, r3, r3, lsl #1
89 addne pc, pc, r3, lsl #3
90 nop
91
92 /* Compare up to 3 bytes */
93 ldrb r0, [ip], #0x01
94 ldrb r3, [r1], #0x01
95 subs r0, r0, r3
96 RETne
97 subs r2, r2, #0x01
98 RETeq
99
100 /* Compare up to 2 bytes */
101 ldrb r0, [ip], #0x01
102 ldrb r3, [r1], #0x01
103 subs r0, r0, r3
104 RETne
105 subs r2, r2, #0x01
106 RETeq
107
108 /* Compare 1 byte */
109 ldrb r0, [ip], #0x01
110 ldrb r3, [r1], #0x01
111 subs r0, r0, r3
112 RETne
113 subs r2, r2, #0x01
114 RETeq
115
116 /* Compare 4 bytes at a time, if possible */
117 subs r2, r2, #0x04
118 bcc .Lmemcmp_bytewise
119.Lmemcmp_word_aligned:
120 ldr r0, [ip], #0x04
121 ldr r3, [r1], #0x04
122 subs r2, r2, #0x04
123 cmpcs r0, r3
124 beq .Lmemcmp_word_aligned
125 sub r0, r0, r3
126
127 /* Correct for extra subtraction, and check if done */
128 adds r2, r2, #0x04
129 cmpeq r0, #0x00 /* If done, did all bytes match? */
130 RETeq /* Yup. Just return */
131
132 /* Re-do the final word byte-wise */
133 sub ip, ip, #0x04
134 sub r1, r1, #0x04
135
136.Lmemcmp_bytewise:
137 add r2, r2, #0x03
138.Lmemcmp_bytewise2:
139 ldrb r0, [ip], #0x01
140 ldrb r3, [r1], #0x01
141 subs r2, r2, #0x01
142 cmpcs r0, r3
143 beq .Lmemcmp_bytewise2
144 sub r0, r0, r3
145 RET
146
147#if defined(_KERNEL) && !defined(_STANDALONE)
148 /*
149 * 6 byte compares are very common, thanks to the network stack.
150 * This code is hand-scheduled to reduce the number of stalls for
151 * load results. Everything else being equal, this will be ~32%
152 * faster than a byte-wise memcmp.
153 */
154 .align 5
155.Lmemcmp_6bytes:
156 ldrb r3, [r1, #0x00] /* r3 = b2#0 */
157 ldrb r0, [ip, #0x00] /* r0 = b1#0 */
158 ldrb r2, [r1, #0x01] /* r2 = b2#1 */
159 subs r0, r0, r3 /* r0 = b1#0 - b2#0 */
160 ldreqb r3, [ip, #0x01] /* r3 = b1#1 */
161 RETne /* Return if mismatch on #0 */
162 subs r0, r3, r2 /* r0 = b1#1 - b2#1 */
163 ldreqb r3, [r1, #0x02] /* r3 = b2#2 */
164 ldreqb r0, [ip, #0x02] /* r0 = b1#2 */
165 RETne /* Return if mismatch on #1 */
166 ldrb r2, [r1, #0x03] /* r2 = b2#3 */
167 subs r0, r0, r3 /* r0 = b1#2 - b2#2 */
168 ldreqb r3, [ip, #0x03] /* r3 = b1#3 */
169 RETne /* Return if mismatch on #2 */
170 subs r0, r3, r2 /* r0 = b1#3 - b2#3 */
171 ldreqb r3, [r1, #0x04] /* r3 = b2#4 */
172 ldreqb r0, [ip, #0x04] /* r0 = b1#4 */
173 RETne /* Return if mismatch on #3 */
174 ldrb r2, [r1, #0x05] /* r2 = b2#5 */
175 subs r0, r0, r3 /* r0 = b1#4 - b2#4 */
176 ldreqb r3, [ip, #0x05] /* r3 = b1#5 */
177 RETne /* Return if mismatch on #4 */
178 sub r0, r3, r2 /* r0 = b1#5 - b2#5 */
179 RET
180#endif
| 68
69ENTRY(memcmp)
70 mov ip, r0
71#if defined(_KERNEL) && !defined(_STANDALONE)
72 cmp r2, #0x06
73 beq .Lmemcmp_6bytes
74#endif
75 mov r0, #0x00
76
77 /* Are both addresses aligned the same way? */
78 cmp r2, #0x00
79 eornes r3, ip, r1
80 RETeq /* len == 0, or same addresses! */
81 tst r3, #0x03
82 subne r2, r2, #0x01
83 bne .Lmemcmp_bytewise2 /* Badly aligned. Do it the slow way */
84
85 /* Word-align the addresses, if necessary */
86 sub r3, r1, #0x05
87 ands r3, r3, #0x03
88 add r3, r3, r3, lsl #1
89 addne pc, pc, r3, lsl #3
90 nop
91
92 /* Compare up to 3 bytes */
93 ldrb r0, [ip], #0x01
94 ldrb r3, [r1], #0x01
95 subs r0, r0, r3
96 RETne
97 subs r2, r2, #0x01
98 RETeq
99
100 /* Compare up to 2 bytes */
101 ldrb r0, [ip], #0x01
102 ldrb r3, [r1], #0x01
103 subs r0, r0, r3
104 RETne
105 subs r2, r2, #0x01
106 RETeq
107
108 /* Compare 1 byte */
109 ldrb r0, [ip], #0x01
110 ldrb r3, [r1], #0x01
111 subs r0, r0, r3
112 RETne
113 subs r2, r2, #0x01
114 RETeq
115
116 /* Compare 4 bytes at a time, if possible */
117 subs r2, r2, #0x04
118 bcc .Lmemcmp_bytewise
119.Lmemcmp_word_aligned:
120 ldr r0, [ip], #0x04
121 ldr r3, [r1], #0x04
122 subs r2, r2, #0x04
123 cmpcs r0, r3
124 beq .Lmemcmp_word_aligned
125 sub r0, r0, r3
126
127 /* Correct for extra subtraction, and check if done */
128 adds r2, r2, #0x04
129 cmpeq r0, #0x00 /* If done, did all bytes match? */
130 RETeq /* Yup. Just return */
131
132 /* Re-do the final word byte-wise */
133 sub ip, ip, #0x04
134 sub r1, r1, #0x04
135
136.Lmemcmp_bytewise:
137 add r2, r2, #0x03
138.Lmemcmp_bytewise2:
139 ldrb r0, [ip], #0x01
140 ldrb r3, [r1], #0x01
141 subs r2, r2, #0x01
142 cmpcs r0, r3
143 beq .Lmemcmp_bytewise2
144 sub r0, r0, r3
145 RET
146
147#if defined(_KERNEL) && !defined(_STANDALONE)
148 /*
149 * 6 byte compares are very common, thanks to the network stack.
150 * This code is hand-scheduled to reduce the number of stalls for
151 * load results. Everything else being equal, this will be ~32%
152 * faster than a byte-wise memcmp.
153 */
154 .align 5
155.Lmemcmp_6bytes:
156 ldrb r3, [r1, #0x00] /* r3 = b2#0 */
157 ldrb r0, [ip, #0x00] /* r0 = b1#0 */
158 ldrb r2, [r1, #0x01] /* r2 = b2#1 */
159 subs r0, r0, r3 /* r0 = b1#0 - b2#0 */
160 ldreqb r3, [ip, #0x01] /* r3 = b1#1 */
161 RETne /* Return if mismatch on #0 */
162 subs r0, r3, r2 /* r0 = b1#1 - b2#1 */
163 ldreqb r3, [r1, #0x02] /* r3 = b2#2 */
164 ldreqb r0, [ip, #0x02] /* r0 = b1#2 */
165 RETne /* Return if mismatch on #1 */
166 ldrb r2, [r1, #0x03] /* r2 = b2#3 */
167 subs r0, r0, r3 /* r0 = b1#2 - b2#2 */
168 ldreqb r3, [ip, #0x03] /* r3 = b1#3 */
169 RETne /* Return if mismatch on #2 */
170 subs r0, r3, r2 /* r0 = b1#3 - b2#3 */
171 ldreqb r3, [r1, #0x04] /* r3 = b2#4 */
172 ldreqb r0, [ip, #0x04] /* r0 = b1#4 */
173 RETne /* Return if mismatch on #3 */
174 ldrb r2, [r1, #0x05] /* r2 = b2#5 */
175 subs r0, r0, r3 /* r0 = b1#4 - b2#4 */
176 ldreqb r3, [ip, #0x05] /* r3 = b1#5 */
177 RETne /* Return if mismatch on #4 */
178 sub r0, r3, r2 /* r0 = b1#5 - b2#5 */
179 RET
180#endif
|