linux/arch/x86/include/asm/string_32.h

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#ifndef _ASM_X86_STRING_32_H
#define _ASM_X86_STRING_32_H
#ifdef __KERNEL__
/* Let gcc decide whether to inline or use the out of line functions */
#define __HAVE_ARCH_STRCPY
extern char *strcpy(char *dest, const char *src);
#define __HAVE_ARCH_STRNCPY
extern char *strncpy(char *dest, const char *src, size_t count);
#define __HAVE_ARCH_STRCAT
extern char *strcat(char *dest, const char *src);
#define __HAVE_ARCH_STRNCAT
extern char *strncat(char *dest, const char *src, size_t count);
#define __HAVE_ARCH_STRCMP
extern int strcmp(const char *cs, const char *ct);
#define __HAVE_ARCH_STRNCMP
extern int strncmp(const char *cs, const char *ct, size_t count);
#define __HAVE_ARCH_STRCHR
extern char *strchr(const char *s, int c);
#define __HAVE_ARCH_STRLEN
extern size_t strlen(const char *s);
static __always_inline void *__memcpy(void *to, const void *from, size_t n)
{
int d0, d1, d2;
asm volatile("rep ; movsl\n\t"
"movl %4,%%ecx\n\t"
"andl $3,%%ecx\n\t"
"jz 1f\n\t"
"rep ; movsb\n\t"
"1:"
: "=&c" (d0), "=&D" (d1), "=&S" (d2)
: "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from)
: "memory");
return to;
}
/*
* This looks ugly, but the compiler can optimize it totally,
* as the count is constant.
*/
static __always_inline void *__constant_memcpy(void *to, const void *from,
size_t n)
{
long esi, edi;
if (!n)
return to;
switch (n) {
case 1:
*(char *)to = *(char *)from;
return to;
case 2:
*(short *)to = *(short *)from;
return to;
case 4:
*(int *)to = *(int *)from;
return to;
case 3:
*(short *)to = *(short *)from;
*((char *)to + 2) = *((char *)from + 2);
return to;
case 5:
*(int *)to = *(int *)from;
*((char *)to + 4) = *((char *)from + 4);
return to;
case 6:
*(int *)to = *(int *)from;
*((short *)to + 2) = *((short *)from + 2);
return to;
case 8:
*(int *)to = *(int *)from;
*((int *)to + 1) = *((int *)from + 1);
return to;
}
esi = (long)from;
edi = (long)to;
if (n >= 5 * 4) {
/* large block: use rep prefix */
int ecx;
asm volatile("rep ; movsl"
: "=&c" (ecx), "=&D" (edi), "=&S" (esi)
: "0" (n / 4), "1" (edi), "2" (esi)
: "memory"
);
} else {
/* small block: don't clobber ecx + smaller code */
if (n >= 4 * 4)
asm volatile("movsl"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
if (n >= 3 * 4)
asm volatile("movsl"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
if (n >= 2 * 4)
asm volatile("movsl"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
if (n >= 1 * 4)
asm volatile("movsl"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
}
switch (n % 4) {
/* tail */
case 0:
return to;
case 1:
asm volatile("movsb"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
return to;
case 2:
asm volatile("movsw"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
return to;
default:
asm volatile("movsw\n\tmovsb"
: "=&D"(edi), "=&S"(esi)
: "0"(edi), "1"(esi)
: "memory");
return to;
}
}
#define __HAVE_ARCH_MEMCPY
#ifdef CONFIG_X86_USE_3DNOW
#include <asm/mmx.h>
/*
* This CPU favours 3DNow strongly (eg AMD Athlon)
*/
static inline void *__constant_memcpy3d(void *to, const void *from, size_t len)
{
if (len < 512)
return __constant_memcpy(to, from, len);
return _mmx_memcpy(to, from, len);
}
static inline void *__memcpy3d(void *to, const void *from, size_t len)
{
if (len < 512)
return __memcpy(to, from, len);
return _mmx_memcpy(to, from, len);
}
#define memcpy(t, f, n) \
(__builtin_constant_p((n)) \
? __constant_memcpy3d((t), (f), (n)) \
: __memcpy3d((t), (f), (n)))
#else
/*
* No 3D Now!
*/
#ifndef CONFIG_KMEMCHECK
#if (__GNUC__ >= 4)
#define memcpy(t, f, n) __builtin_memcpy(t, f, n)
#else
#define memcpy(t, f, n) \
(__builtin_constant_p((n)) \
? __constant_memcpy((t), (f), (n)) \
: __memcpy((t), (f), (n)))
#endif
#else
/*
* kmemcheck becomes very happy if we use the REP instructions unconditionally,
* because it means that we know both memory operands in advance.
*/
#define memcpy(t, f, n) __memcpy((t), (f), (n))
#endif
#endif
#define __HAVE_ARCH_MEMMOVE
void *memmove(void *dest, const void *src, size_t n);
#define memcmp __builtin_memcmp
#define __HAVE_ARCH_MEMCHR
extern void *memchr(const void *cs, int c, size_t count);
static inline void *__memset_generic(void *s, char c, size_t count)
{
int d0, d1;
asm volatile("rep\n\t"
"stosb"
: "=&c" (d0), "=&D" (d1)
: "a" (c), "1" (s), "0" (count)
: "memory");
return s;
}
/* we might want to write optimized versions of these later */
#define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count))
/*
* memset(x, 0, y) is a reasonably common thing to do, so we want to fill
* things 32 bits at a time even when we don't know the size of the
* area at compile-time..
*/
static __always_inline
void *__constant_c_memset(void *s, unsigned long c, size_t count)
{
int d0, d1;
asm volatile("rep ; stosl\n\t"
"testb $2,%b3\n\t"
"je 1f\n\t"
"stosw\n"
"1:\ttestb $1,%b3\n\t"
"je 2f\n\t"
"stosb\n"
"2:"
: "=&c" (d0), "=&D" (d1)
: "a" (c), "q" (count), "0" (count/4), "1" ((long)s)
: "memory");
return s;
}
/* Added by Gertjan van Wingerde to make minix and sysv module work */
#define __HAVE_ARCH_STRNLEN
extern size_t strnlen(const char *s, size_t count);
/* end of additional stuff */
#define __HAVE_ARCH_STRSTR
extern char *strstr(const char *cs, const char *ct);
/*
* This looks horribly ugly, but the compiler can optimize it totally,
* as we by now know that both pattern and count is constant..
*/
static __always_inline
void *__constant_c_and_count_memset(void *s, unsigned long pattern,
size_t count)
{
switch (count) {
case 0:
return s;
case 1:
*(unsigned char *)s = pattern & 0xff;
return s;
case 2:
*(unsigned short *)s = pattern & 0xffff;
return s;
case 3:
*(unsigned short *)s = pattern & 0xffff;
*((unsigned char *)s + 2) = pattern & 0xff;
return s;
case 4:
*(unsigned long *)s = pattern;
return s;
}
#define COMMON(x) \
asm volatile("rep ; stosl" \
x \
: "=&c" (d0), "=&D" (d1) \
: "a" (eax), "0" (count/4), "1" ((long)s) \
: "memory")
{
int d0, d1;
#if __GNUC__ == 4 && __GNUC_MINOR__ == 0
/* Workaround for broken gcc 4.0 */
register unsigned long eax asm("%eax") = pattern;
#else
unsigned long eax = pattern;
#endif
switch (count % 4) {
case 0:
COMMON("");
return s;
case 1:
COMMON("\n\tstosb");
return s;
case 2:
COMMON("\n\tstosw");
return s;
default:
COMMON("\n\tstosw\n\tstosb");
return s;
}
}
#undef COMMON
}
#define __constant_c_x_memset(s, c, count) \
(__builtin_constant_p(count) \
? __constant_c_and_count_memset((s), (c), (count)) \
: __constant_c_memset((s), (c), (count)))
#define __memset(s, c, count) \
(__builtin_constant_p(count) \
? __constant_count_memset((s), (c), (count)) \
: __memset_generic((s), (c), (count)))
#define __HAVE_ARCH_MEMSET
#if (__GNUC__ >= 4)
#define memset(s, c, count) __builtin_memset(s, c, count)
#else
#define memset(s, c, count) \
(__builtin_constant_p(c) \
? __constant_c_x_memset((s), (0x01010101UL * (unsigned char)(c)), \
(count)) \
: __memset((s), (c), (count)))
#endif
/*
* find the first occurrence of byte 'c', or 1 past the area if none
*/
#define __HAVE_ARCH_MEMSCAN
extern void *memscan(void *addr, int c, size_t size);
#endif /* __KERNEL__ */
#endif /* _ASM_X86_STRING_32_H */