[PATCH 2/5] m68k: cleanup string functions

From: zippel
Date: Wed Oct 04 2006 - 19:28:11 EST


- cleanup asm of string functions
- deinline strncat()/strncmp()
- provide non-inlined strcpy()

Signed-off-by: Roman Zippel <zippel@xxxxxxxxxxxxxx>

---
arch/m68k/kernel/m68k_ksyms.c | 4
arch/m68k/lib/string.c | 15 +++
include/asm-m68k/string.h | 194 ++++++++++++++++++------------------------
3 files changed, 100 insertions(+), 113 deletions(-)

Index: linux-2.6/arch/m68k/kernel/m68k_ksyms.c
===================================================================
--- linux-2.6.orig/arch/m68k/kernel/m68k_ksyms.c
+++ linux-2.6/arch/m68k/kernel/m68k_ksyms.c
@@ -1,7 +1,6 @@
#include <linux/module.h>
#include <linux/linkage.h>
#include <linux/sched.h>
-#include <linux/string.h>
#include <linux/mm.h>
#include <linux/user.h>
#include <linux/elfcore.h>
@@ -53,9 +52,6 @@ EXPORT_SYMBOL(mach_beep);
#endif
EXPORT_SYMBOL(dump_fpu);
EXPORT_SYMBOL(dump_thread);
-EXPORT_SYMBOL(strnlen);
-EXPORT_SYMBOL(strrchr);
-EXPORT_SYMBOL(strstr);
EXPORT_SYMBOL(kernel_thread);
#ifdef CONFIG_VME
EXPORT_SYMBOL(vme_brdtype);
Index: linux-2.6/arch/m68k/lib/string.c
===================================================================
--- linux-2.6.orig/arch/m68k/lib/string.c
+++ linux-2.6/arch/m68k/lib/string.c
@@ -1,6 +1,19 @@
+/*
+ * 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.
+ */
+
+#define __IN_STRING_C

-#include <linux/types.h>
#include <linux/module.h>
+#include <linux/string.h>
+
+char *strcpy(char *dest, const char *src)
+{
+ return __kernel_strcpy(dest, src);
+}
+EXPORT_SYMBOL(strcpy);

void *memset(void *s, int c, size_t count)
{
Index: linux-2.6/include/asm-m68k/string.h
===================================================================
--- linux-2.6.orig/include/asm-m68k/string.h
+++ linux-2.6/include/asm-m68k/string.h
@@ -1,138 +1,114 @@
#ifndef _M68K_STRING_H_
#define _M68K_STRING_H_

-#include <asm/setup.h>
-#include <asm/page.h>
+#include <linux/types.h>
+#include <linux/compiler.h>

-#define __HAVE_ARCH_STRCPY
-static inline char * strcpy(char * dest,const char *src)
+static inline size_t __kernel_strlen(const char *s)
{
- char *xdest = dest;
+ const char *sc;

- __asm__ __volatile__
- ("1:\tmoveb %1@+,%0@+\n\t"
- "jne 1b"
- : "=a" (dest), "=a" (src)
- : "0" (dest), "1" (src) : "memory");
- return xdest;
+ for (sc = s; *sc++; )
+ ;
+ return sc - s - 1;
}

-#define __HAVE_ARCH_STRNCPY
-static inline char * strncpy(char *dest, const char *src, size_t n)
+static inline char *__kernel_strcpy(char *dest, const char *src)
{
- char *xdest = dest;
+ char *xdest = dest;

- if (n == 0)
- return xdest;
-
- __asm__ __volatile__
- ("1:\tmoveb %1@+,%0@+\n\t"
- "jeq 2f\n\t"
- "subql #1,%2\n\t"
- "jne 1b\n\t"
- "2:"
- : "=a" (dest), "=a" (src), "=d" (n)
- : "0" (dest), "1" (src), "2" (n)
- : "memory");
- return xdest;
+ asm volatile ("\n"
+ "1: move.b (%1)+,(%0)+\n"
+ " jne 1b"
+ : "+a" (dest), "+a" (src)
+ : : "memory");
+ return xdest;
}

-#define __HAVE_ARCH_STRCAT
-static inline char * strcat(char * dest, const char * src)
-{
- char *tmp = dest;
-
- while (*dest)
- dest++;
- while ((*dest++ = *src++))
- ;
+#ifndef __IN_STRING_C

- return tmp;
+#define __HAVE_ARCH_STRLEN
+#define strlen(s) (__builtin_constant_p(s) ? \
+ __builtin_strlen(s) : \
+ __kernel_strlen(s))
+
+#define __HAVE_ARCH_STRNLEN
+static inline size_t strnlen(const char *s, size_t count)
+{
+ const char *sc = s;
+
+ asm volatile ("\n"
+ "1: subq.l #1,%1\n"
+ " jcs 2f\n"
+ " tst.b (%0)+\n"
+ " jne 1b\n"
+ " subq.l #1,%0\n"
+ "2:"
+ : "+a" (sc), "+d" (count));
+ return sc - s;
}

-#define __HAVE_ARCH_STRNCAT
-static inline char * strncat(char *dest, const char *src, size_t count)
-{
- char *tmp = dest;
-
- if (count) {
- while (*dest)
- dest++;
- while ((*dest++ = *src++)) {
- if (--count == 0) {
- *dest++='\0';
- break;
- }
- }
- }
-
- return tmp;
-}
+#define __HAVE_ARCH_STRCPY
+#if __GNUC__ >= 4
+#define strcpy(d, s) (__builtin_constant_p(s) && \
+ __builtin_strlen(s) <= 32 ? \
+ __builtin_strcpy(d, s) : \
+ __kernel_strcpy(d, s))
+#else
+#define strcpy(d, s) __kernel_strcpy(d, s)
+#endif

-#define __HAVE_ARCH_STRCHR
-static inline char * strchr(const char * s, int c)
+#define __HAVE_ARCH_STRNCPY
+static inline char *strncpy(char *dest, const char *src, size_t n)
{
- const char ch = c;
+ char *xdest = dest;

- for(; *s != ch; ++s)
- if (*s == '\0')
- return( NULL );
- return( (char *) s);
+ asm volatile ("\n"
+ " jra 2f\n"
+ "1: move.b (%1),(%0)+\n"
+ " jeq 2f\n"
+ " addq.l #1,%1\n"
+ "2: subq.l #1,%2\n"
+ " jcc 1b\n"
+ : "+a" (dest), "+a" (src), "+d" (n)
+ : : "memory");
+ return xdest;
}

-/* strstr !! */
+#define __HAVE_ARCH_STRCAT
+#define strcat(d, s) ({ \
+ char *__d = (d); \
+ strcpy(__d + strlen(__d), (s)); \
+})

-#define __HAVE_ARCH_STRLEN
-static inline size_t strlen(const char * s)
+#define __HAVE_ARCH_STRCHR
+static inline char *strchr(const char *s, int c)
{
- const char *sc;
- for (sc = s; *sc != '\0'; ++sc) ;
- return(sc - s);
-}
+ char sc, ch = c;

-/* strnlen !! */
+ for (; (sc = *s++) != ch; ) {
+ if (!sc)
+ return NULL;
+ }
+ return (char *)s - 1;
+}

#define __HAVE_ARCH_STRCMP
-static inline int strcmp(const char * cs,const char * ct)
+static inline int strcmp(const char *cs, const char *ct)
{
- char __res;
+ char res;

- __asm__
- ("1:\tmoveb %0@+,%2\n\t" /* get *cs */
- "cmpb %1@+,%2\n\t" /* compare a byte */
- "jne 2f\n\t" /* not equal, break out */
- "tstb %2\n\t" /* at end of cs? */
- "jne 1b\n\t" /* no, keep going */
- "jra 3f\n\t" /* strings are equal */
- "2:\tsubb %1@-,%2\n\t" /* *cs - *ct */
- "3:"
- : "=a" (cs), "=a" (ct), "=d" (__res)
- : "0" (cs), "1" (ct));
- return __res;
-}
-
-#define __HAVE_ARCH_STRNCMP
-static inline int strncmp(const char * cs,const char * ct,size_t count)
-{
- char __res;
-
- if (!count)
- return 0;
- __asm__
- ("1:\tmovb %0@+,%3\n\t" /* get *cs */
- "cmpb %1@+,%3\n\t" /* compare a byte */
- "jne 3f\n\t" /* not equal, break out */
- "tstb %3\n\t" /* at end of cs? */
- "jeq 4f\n\t" /* yes, all done */
- "subql #1,%2\n\t" /* no, adjust count */
- "jne 1b\n\t" /* more to do, keep going */
- "2:\tmoveq #0,%3\n\t" /* strings are equal */
- "jra 4f\n\t"
- "3:\tsubb %1@-,%3\n\t" /* *cs - *ct */
- "4:"
- : "=a" (cs), "=a" (ct), "=d" (count), "=d" (__res)
- : "0" (cs), "1" (ct), "2" (count));
- return __res;
+ asm ("\n"
+ "1: move.b (%0)+,%2\n" /* get *cs */
+ " cmp.b (%1)+,%2\n" /* compare a byte */
+ " jne 2f\n" /* not equal, break out */
+ " tst.b %2\n" /* at end of cs? */
+ " jne 1b\n" /* no, keep going */
+ " jra 3f\n" /* strings are equal */
+ "2: sub.b -(%1),%2\n" /* *cs - *ct */
+ "3:"
+ : "+a" (cs), "+a" (ct), "=d" (res));
+ return res;
}

#define __HAVE_ARCH_MEMSET
@@ -150,4 +126,6 @@ extern void *memmove(void *, const void
extern int memcmp(const void *, const void *, __kernel_size_t);
#define memcmp(d, s, n) __builtin_memcmp(d, s, n)

+#endif
+
#endif /* _M68K_STRING_H_ */

--

-
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