kernel-hacking-2024-linux-s.../arch/s390/include/asm/string.h
Heiko Carstens 535c611ddd s390/string: provide asm lib functions for memcpy and memcmp
Our memcpy and memcmp variants were implemented by calling the corresponding
gcc builtin variants.
However gcc is free to replace a call to __builtin_memcmp with a call to memcmp
which, when called, will result in an endless recursion within memcmp.
So let's provide asm variants and also fix the variants that are used for
uncompressing the kernel image.
In addition remove all other occurences of builtin function calls.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26 15:44:50 +02:00

143 lines
3.6 KiB
C

/*
* S390 version
* Copyright IBM Corp. 1999
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
*/
#ifndef _S390_STRING_H_
#define _S390_STRING_H_
#ifndef _LINUX_TYPES_H
#include <linux/types.h>
#endif
#define __HAVE_ARCH_MEMCHR /* inline & arch function */
#define __HAVE_ARCH_MEMCMP /* arch function */
#define __HAVE_ARCH_MEMCPY /* gcc builtin & arch function */
#define __HAVE_ARCH_MEMSCAN /* inline & arch function */
#define __HAVE_ARCH_MEMSET /* gcc builtin & arch function */
#define __HAVE_ARCH_STRCAT /* inline & arch function */
#define __HAVE_ARCH_STRCMP /* arch function */
#define __HAVE_ARCH_STRCPY /* inline & arch function */
#define __HAVE_ARCH_STRLCAT /* arch function */
#define __HAVE_ARCH_STRLCPY /* arch function */
#define __HAVE_ARCH_STRLEN /* inline & arch function */
#define __HAVE_ARCH_STRNCAT /* arch function */
#define __HAVE_ARCH_STRNCPY /* arch function */
#define __HAVE_ARCH_STRNLEN /* inline & arch function */
#define __HAVE_ARCH_STRRCHR /* arch function */
#define __HAVE_ARCH_STRSTR /* arch function */
/* Prototypes for non-inlined arch strings functions. */
extern int memcmp(const void *, const void *, size_t);
extern void *memcpy(void *, const void *, size_t);
extern void *memset(void *, int, size_t);
extern int strcmp(const char *,const char *);
extern size_t strlcat(char *, const char *, size_t);
extern size_t strlcpy(char *, const char *, size_t);
extern char *strncat(char *, const char *, size_t);
extern char *strncpy(char *, const char *, size_t);
extern char *strrchr(const char *, int);
extern char *strstr(const char *, const char *);
#undef __HAVE_ARCH_MEMMOVE
#undef __HAVE_ARCH_STRCHR
#undef __HAVE_ARCH_STRNCHR
#undef __HAVE_ARCH_STRNCMP
#undef __HAVE_ARCH_STRNICMP
#undef __HAVE_ARCH_STRPBRK
#undef __HAVE_ARCH_STRSEP
#undef __HAVE_ARCH_STRSPN
#if !defined(IN_ARCH_STRING_C)
static inline void *memchr(const void * s, int c, size_t n)
{
register int r0 asm("0") = (char) c;
const void *ret = s + n;
asm volatile(
"0: srst %0,%1\n"
" jo 0b\n"
" jl 1f\n"
" la %0,0\n"
"1:"
: "+a" (ret), "+&a" (s) : "d" (r0) : "cc");
return (void *) ret;
}
static inline void *memscan(void *s, int c, size_t n)
{
register int r0 asm("0") = (char) c;
const void *ret = s + n;
asm volatile(
"0: srst %0,%1\n"
" jo 0b\n"
: "+a" (ret), "+&a" (s) : "d" (r0) : "cc");
return (void *) ret;
}
static inline char *strcat(char *dst, const char *src)
{
register int r0 asm("0") = 0;
unsigned long dummy;
char *ret = dst;
asm volatile(
"0: srst %0,%1\n"
" jo 0b\n"
"1: mvst %0,%2\n"
" jo 1b"
: "=&a" (dummy), "+a" (dst), "+a" (src)
: "d" (r0), "0" (0) : "cc", "memory" );
return ret;
}
static inline char *strcpy(char *dst, const char *src)
{
register int r0 asm("0") = 0;
char *ret = dst;
asm volatile(
"0: mvst %0,%1\n"
" jo 0b"
: "+&a" (dst), "+&a" (src) : "d" (r0)
: "cc", "memory");
return ret;
}
static inline size_t strlen(const char *s)
{
register unsigned long r0 asm("0") = 0;
const char *tmp = s;
asm volatile(
"0: srst %0,%1\n"
" jo 0b"
: "+d" (r0), "+a" (tmp) : : "cc");
return r0 - (unsigned long) s;
}
static inline size_t strnlen(const char * s, size_t n)
{
register int r0 asm("0") = 0;
const char *tmp = s;
const char *end = s + n;
asm volatile(
"0: srst %0,%1\n"
" jo 0b"
: "+a" (end), "+a" (tmp) : "d" (r0) : "cc");
return end - s;
}
#else /* IN_ARCH_STRING_C */
void *memchr(const void * s, int c, size_t n);
void *memscan(void *s, int c, size_t n);
char *strcat(char *dst, const char *src);
char *strcpy(char *dst, const char *src);
size_t strlen(const char *s);
size_t strnlen(const char * s, size_t n);
#endif /* !IN_ARCH_STRING_C */
#endif /* __S390_STRING_H_ */