1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_STRING_32_H
3#define _ASM_X86_STRING_32_H
4
5#ifdef __KERNEL__
6
7/* Let gcc decide whether to inline or use the out of line functions */
8
9#define __HAVE_ARCH_STRCPY
10extern char *strcpy(char *dest, const char *src);
11
12#define __HAVE_ARCH_STRNCPY
13extern char *strncpy(char *dest, const char *src, size_t count);
14
15#define __HAVE_ARCH_STRCAT
16extern char *strcat(char *dest, const char *src);
17
18#define __HAVE_ARCH_STRNCAT
19extern char *strncat(char *dest, const char *src, size_t count);
20
21#define __HAVE_ARCH_STRCMP
22extern int strcmp(const char *cs, const char *ct);
23
24#define __HAVE_ARCH_STRNCMP
25extern int strncmp(const char *cs, const char *ct, size_t count);
26
27#define __HAVE_ARCH_STRCHR
28extern char *strchr(const char *s, int c);
29
30#define __HAVE_ARCH_STRLEN
31extern size_t strlen(const char *s);
32
33static __always_inline void *__memcpy(void *to, const void *from, size_t n)
34{
35 int d0, d1, d2;
36 asm volatile("rep ; movsl\n\t"
37 "movl %4,%%ecx\n\t"
38 "andl $3,%%ecx\n\t"
39 "jz 1f\n\t"
40 "rep ; movsb\n\t"
41 "1:"
42 : "=&c" (d0), "=&D" (d1), "=&S" (d2)
43 : "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from)
44 : "memory");
45 return to;
46}
47
48/*
49 * This looks ugly, but the compiler can optimize it totally,
50 * as the count is constant.
51 */
52static __always_inline void *__constant_memcpy(void *to, const void *from,
53 size_t n)
54{
55 long esi, edi;
56 if (!n)
57 return to;
58
59 switch (n) {
60 case 1:
61 *(char *)to = *(char *)from;
62 return to;
63 case 2:
64 *(short *)to = *(short *)from;
65 return to;
66 case 4:
67 *(int *)to = *(int *)from;
68 return to;
69 case 3:
70 *(short *)to = *(short *)from;
71 *((char *)to + 2) = *((char *)from + 2);
72 return to;
73 case 5:
74 *(int *)to = *(int *)from;
75 *((char *)to + 4) = *((char *)from + 4);
76 return to;
77 case 6:
78 *(int *)to = *(int *)from;
79 *((short *)to + 2) = *((short *)from + 2);
80 return to;
81 case 8:
82 *(int *)to = *(int *)from;
83 *((int *)to + 1) = *((int *)from + 1);
84 return to;
85 }
86
87 esi = (long)from;
88 edi = (long)to;
89 if (n >= 5 * 4) {
90 /* large block: use rep prefix */
91 int ecx;
92 asm volatile("rep ; movsl"
93 : "=&c" (ecx), "=&D" (edi), "=&S" (esi)
94 : "0" (n / 4), "1" (edi), "2" (esi)
95 : "memory"
96 );
97 } else {
98 /* small block: don't clobber ecx + smaller code */
99 if (n >= 4 * 4)
100 asm volatile("movsl"
101 : "=&D"(edi), "=&S"(esi)
102 : "0"(edi), "1"(esi)
103 : "memory");
104 if (n >= 3 * 4)
105 asm volatile("movsl"
106 : "=&D"(edi), "=&S"(esi)
107 : "0"(edi), "1"(esi)
108 : "memory");
109 if (n >= 2 * 4)
110 asm volatile("movsl"
111 : "=&D"(edi), "=&S"(esi)
112 : "0"(edi), "1"(esi)
113 : "memory");
114 if (n >= 1 * 4)
115 asm volatile("movsl"
116 : "=&D"(edi), "=&S"(esi)
117 : "0"(edi), "1"(esi)
118 : "memory");
119 }
120 switch (n % 4) {
121 /* tail */
122 case 0:
123 return to;
124 case 1:
125 asm volatile("movsb"
126 : "=&D"(edi), "=&S"(esi)
127 : "0"(edi), "1"(esi)
128 : "memory");
129 return to;
130 case 2:
131 asm volatile("movsw"
132 : "=&D"(edi), "=&S"(esi)
133 : "0"(edi), "1"(esi)
134 : "memory");
135 return to;
136 default:
137 asm volatile("movsw\n\tmovsb"
138 : "=&D"(edi), "=&S"(esi)
139 : "0"(edi), "1"(esi)
140 : "memory");
141 return to;
142 }
143}
144
145#define __HAVE_ARCH_MEMCPY
146extern void *memcpy(void *, const void *, size_t);
147
148#ifndef CONFIG_FORTIFY_SOURCE
149#ifdef CONFIG_X86_USE_3DNOW
150
151#include <asm/mmx.h>
152
153/*
154 * This CPU favours 3DNow strongly (eg AMD Athlon)
155 */
156
157static inline void *__constant_memcpy3d(void *to, const void *from, size_t len)
158{
159 if (len < 512)
160 return __constant_memcpy(to, from, len);
161 return _mmx_memcpy(to, from, len);
162}
163
164static inline void *__memcpy3d(void *to, const void *from, size_t len)
165{
166 if (len < 512)
167 return __memcpy(to, from, len);
168 return _mmx_memcpy(to, from, len);
169}
170
171#define memcpy(t, f, n) \
172 (__builtin_constant_p((n)) \
173 ? __constant_memcpy3d((t), (f), (n)) \
174 : __memcpy3d((t), (f), (n)))
175
176#else
177
178/*
179 * No 3D Now!
180 */
181
182#define memcpy(t, f, n) __builtin_memcpy(t, f, n)
183
184#endif
185#endif /* !CONFIG_FORTIFY_SOURCE */
186
187#define __HAVE_ARCH_MEMMOVE
188void *memmove(void *dest, const void *src, size_t n);
189
190extern int memcmp(const void *, const void *, size_t);
191#ifndef CONFIG_FORTIFY_SOURCE
192#define memcmp __builtin_memcmp
193#endif
194
195#define __HAVE_ARCH_MEMCHR
196extern void *memchr(const void *cs, int c, size_t count);
197
198static inline void *__memset_generic(void *s, char c, size_t count)
199{
200 int d0, d1;
201 asm volatile("rep\n\t"
202 "stosb"
203 : "=&c" (d0), "=&D" (d1)
204 : "a" (c), "1" (s), "0" (count)
205 : "memory");
206 return s;
207}
208
209/* we might want to write optimized versions of these later */
210#define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count))
211
212/* Added by Gertjan van Wingerde to make minix and sysv module work */
213#define __HAVE_ARCH_STRNLEN
214extern size_t strnlen(const char *s, size_t count);
215/* end of additional stuff */
216
217#define __HAVE_ARCH_STRSTR
218extern char *strstr(const char *cs, const char *ct);
219
220#define __memset(s, c, count) \
221 (__builtin_constant_p(count) \
222 ? __constant_count_memset((s), (c), (count)) \
223 : __memset_generic((s), (c), (count)))
224
225#define __HAVE_ARCH_MEMSET
226extern void *memset(void *, int, size_t);
227#ifndef CONFIG_FORTIFY_SOURCE
228#define memset(s, c, count) __builtin_memset(s, c, count)
229#endif /* !CONFIG_FORTIFY_SOURCE */
230
231#define __HAVE_ARCH_MEMSET16
232static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
233{
234 int d0, d1;
235 asm volatile("rep\n\t"
236 "stosw"
237 : "=&c" (d0), "=&D" (d1)
238 : "a" (v), "1" (s), "0" (n)
239 : "memory");
240 return s;
241}
242
243#define __HAVE_ARCH_MEMSET32
244static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
245{
246 int d0, d1;
247 asm volatile("rep\n\t"
248 "stosl"
249 : "=&c" (d0), "=&D" (d1)
250 : "a" (v), "1" (s), "0" (n)
251 : "memory");
252 return s;
253}
254
255/*
256 * find the first occurrence of byte 'c', or 1 past the area if none
257 */
258#define __HAVE_ARCH_MEMSCAN
259extern void *memscan(void *addr, int c, size_t size);
260
261#endif /* __KERNEL__ */
262
263#endif /* _ASM_X86_STRING_32_H */
264