xref: /linux/arch/xtensa/include/asm/string.h (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1 /*
2  * include/asm-xtensa/string.h
3  *
4  * These trivial string functions are considered part of the public domain.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  *
10  * Copyright (C) 2001 - 2005 Tensilica Inc.
11  */
12 
13 /* We should optimize these. See arch/xtensa/lib/strncpy_user.S */
14 
15 #ifndef _XTENSA_STRING_H
16 #define _XTENSA_STRING_H
17 
18 #define __HAVE_ARCH_STRCPY
19 static inline char *strcpy(char *__dest, const char *__src)
20 {
21 	register char *__xdest = __dest;
22 	unsigned long __dummy;
23 
24 	__asm__ __volatile__("1:\n\t"
25 		"l8ui	%2, %1, 0\n\t"
26 		"s8i	%2, %0, 0\n\t"
27 		"addi	%1, %1, 1\n\t"
28 		"addi	%0, %0, 1\n\t"
29 		"bnez	%2, 1b\n\t"
30 		: "=r" (__dest), "=r" (__src), "=&r" (__dummy)
31 		: "0" (__dest), "1" (__src)
32 		: "memory");
33 
34 	return __xdest;
35 }
36 
37 #define __HAVE_ARCH_STRNCPY
38 static inline char *strncpy(char *__dest, const char *__src, size_t __n)
39 {
40 	register char *__xdest = __dest;
41 	unsigned long __dummy;
42 
43 	if (__n == 0)
44 		return __xdest;
45 
46 	__asm__ __volatile__(
47 		"1:\n\t"
48 		"l8ui	%2, %1, 0\n\t"
49 		"s8i	%2, %0, 0\n\t"
50 		"addi	%1, %1, 1\n\t"
51 		"addi	%0, %0, 1\n\t"
52 		"beqz	%2, 2f\n\t"
53 		"bne	%1, %5, 1b\n"
54 		"2:"
55 		: "=r" (__dest), "=r" (__src), "=&r" (__dummy)
56 		: "0" (__dest), "1" (__src), "r" ((uintptr_t)__src+__n)
57 		: "memory");
58 
59 	return __xdest;
60 }
61 
62 #define __HAVE_ARCH_STRCMP
63 static inline int strcmp(const char *__cs, const char *__ct)
64 {
65 	register int __res;
66 	unsigned long __dummy;
67 
68 	__asm__ __volatile__(
69 		"1:\n\t"
70 		"l8ui	%3, %1, 0\n\t"
71 		"addi	%1, %1, 1\n\t"
72 		"l8ui	%2, %0, 0\n\t"
73 		"addi	%0, %0, 1\n\t"
74 		"beqz	%2, 2f\n\t"
75 		"beq	%2, %3, 1b\n"
76 		"2:\n\t"
77 		"sub	%2, %2, %3"
78 		: "=r" (__cs), "=r" (__ct), "=&r" (__res), "=&r" (__dummy)
79 		: "0" (__cs), "1" (__ct));
80 
81 	return __res;
82 }
83 
84 #define __HAVE_ARCH_STRNCMP
85 static inline int strncmp(const char *__cs, const char *__ct, size_t __n)
86 {
87 	register int __res;
88 	unsigned long __dummy;
89 
90 	__asm__ __volatile__(
91 		"mov	%2, %3\n"
92 		"1:\n\t"
93 		"beq	%0, %6, 2f\n\t"
94 		"l8ui	%3, %1, 0\n\t"
95 		"addi	%1, %1, 1\n\t"
96 		"l8ui	%2, %0, 0\n\t"
97 		"addi	%0, %0, 1\n\t"
98 		"beqz	%2, 2f\n\t"
99 		"beqz	%3, 2f\n\t"
100 		"beq	%2, %3, 1b\n"
101 		"2:\n\t"
102 		"sub	%2, %2, %3"
103 		: "=r" (__cs), "=r" (__ct), "=&r" (__res), "=&r" (__dummy)
104 		: "0" (__cs), "1" (__ct), "r" ((uintptr_t)__cs+__n));
105 
106 	return __res;
107 }
108 
109 #define __HAVE_ARCH_MEMSET
110 extern void *memset(void *__s, int __c, size_t __count);
111 extern void *__memset(void *__s, int __c, size_t __count);
112 
113 #define __HAVE_ARCH_MEMCPY
114 extern void *memcpy(void *__to, __const__ void *__from, size_t __n);
115 extern void *__memcpy(void *__to, __const__ void *__from, size_t __n);
116 
117 #define __HAVE_ARCH_MEMMOVE
118 extern void *memmove(void *__dest, __const__ void *__src, size_t __n);
119 extern void *__memmove(void *__dest, __const__ void *__src, size_t __n);
120 
121 #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
122 
123 /*
124  * For files that are not instrumented (e.g. mm/slub.c) we
125  * should use not instrumented version of mem* functions.
126  */
127 
128 #define memcpy(dst, src, len) __memcpy(dst, src, len)
129 #define memmove(dst, src, len) __memmove(dst, src, len)
130 #define memset(s, c, n) __memset(s, c, n)
131 
132 #ifndef __NO_FORTIFY
133 #define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
134 #endif
135 #endif
136 
137 #endif	/* _XTENSA_STRING_H */
138