linux/arch/xtensa/include/asm/string.h
Max Filippov c5a285bb1b xtensa: fix str[n]cmp return value
str[n]cmp functions return negative value if the first string is less
than the second, positive value if the first string is greater than the
second and zero if they are equal. This is important when these
functions are used for sorting/binary search.

With incorrect strcmp return value bsearch was always failing in the
find_symbol_in_section making it impossible to load any module.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2013-02-23 19:22:31 -08:00

122 lines
2.7 KiB
C

/*
* include/asm-xtensa/string.h
*
* These trivial string functions are considered part of the public domain.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
/* We should optimize these. See arch/xtensa/lib/strncpy_user.S */
#ifndef _XTENSA_STRING_H
#define _XTENSA_STRING_H
#define __HAVE_ARCH_STRCPY
static inline char *strcpy(char *__dest, const char *__src)
{
register char *__xdest = __dest;
unsigned long __dummy;
__asm__ __volatile__("1:\n\t"
"l8ui %2, %1, 0\n\t"
"s8i %2, %0, 0\n\t"
"addi %1, %1, 1\n\t"
"addi %0, %0, 1\n\t"
"bnez %2, 1b\n\t"
: "=r" (__dest), "=r" (__src), "=&r" (__dummy)
: "0" (__dest), "1" (__src)
: "memory");
return __xdest;
}
#define __HAVE_ARCH_STRNCPY
static inline char *strncpy(char *__dest, const char *__src, size_t __n)
{
register char *__xdest = __dest;
unsigned long __dummy;
if (__n == 0)
return __xdest;
__asm__ __volatile__(
"1:\n\t"
"l8ui %2, %1, 0\n\t"
"s8i %2, %0, 0\n\t"
"addi %1, %1, 1\n\t"
"addi %0, %0, 1\n\t"
"beqz %2, 2f\n\t"
"bne %1, %5, 1b\n"
"2:"
: "=r" (__dest), "=r" (__src), "=&r" (__dummy)
: "0" (__dest), "1" (__src), "r" (__src+__n)
: "memory");
return __xdest;
}
#define __HAVE_ARCH_STRCMP
static inline int strcmp(const char *__cs, const char *__ct)
{
register int __res;
unsigned long __dummy;
__asm__ __volatile__(
"1:\n\t"
"l8ui %3, %1, 0\n\t"
"addi %1, %1, 1\n\t"
"l8ui %2, %0, 0\n\t"
"addi %0, %0, 1\n\t"
"beqz %2, 2f\n\t"
"beq %2, %3, 1b\n"
"2:\n\t"
"sub %2, %2, %3"
: "=r" (__cs), "=r" (__ct), "=&r" (__res), "=&r" (__dummy)
: "0" (__cs), "1" (__ct));
return __res;
}
#define __HAVE_ARCH_STRNCMP
static inline int strncmp(const char *__cs, const char *__ct, size_t __n)
{
register int __res;
unsigned long __dummy;
__asm__ __volatile__(
"mov %2, %3\n"
"1:\n\t"
"beq %0, %6, 2f\n\t"
"l8ui %3, %1, 0\n\t"
"addi %1, %1, 1\n\t"
"l8ui %2, %0, 0\n\t"
"addi %0, %0, 1\n\t"
"beqz %2, 2f\n\t"
"beqz %3, 2f\n\t"
"beq %2, %3, 1b\n"
"2:\n\t"
"sub %2, %2, %3"
: "=r" (__cs), "=r" (__ct), "=&r" (__res), "=&r" (__dummy)
: "0" (__cs), "1" (__ct), "r" (__cs+__n));
return __res;
}
#define __HAVE_ARCH_MEMSET
extern void *memset(void *__s, int __c, size_t __count);
#define __HAVE_ARCH_MEMCPY
extern void *memcpy(void *__to, __const__ void *__from, size_t __n);
#define __HAVE_ARCH_MEMMOVE
extern void *memmove(void *__dest, __const__ void *__src, size_t __n);
/* Don't build bcopy at all ... */
#define __HAVE_ARCH_BCOPY
#endif /* _XTENSA_STRING_H */