[PATCH] m68k: fix strcmp inline

From: Andreas Schwab
Date: Fri Dec 16 2022 - 11:35:26 EST


The return value of strcmp needs to be computed from the ordering of the
unsigned characters.

Signed-off-by: Andreas Schwab <schwab@xxxxxxxxxxxxxx>
---
arch/m68k/include/asm/string.h | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/m68k/include/asm/string.h b/arch/m68k/include/asm/string.h
index f759d944c449..cdafd67774e0 100644
--- a/arch/m68k/include/asm/string.h
+++ b/arch/m68k/include/asm/string.h
@@ -42,18 +42,19 @@ static inline char *strncpy(char *dest, const char *src, size_t n)
#define __HAVE_ARCH_STRCMP
static inline int strcmp(const char *cs, const char *ct)
{
- char res;
+ int res = 0, tmp = 0;

asm ("\n"
"1: move.b (%0)+,%2\n" /* get *cs */
- " cmp.b (%1)+,%2\n" /* compare a byte */
+ " move.b (%1)+,%3\n" /* get *ct */
+ " cmp.b %3,%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 */
+ "2: sub.l %3,%2\n" /* *cs - *ct */
"3:"
- : "+a" (cs), "+a" (ct), "=d" (res));
+ : "+a" (cs), "+a" (ct), "+d" (res), "+d" (tmp));
return res;
}
#endif /* CONFIG_COLDFIRE */
--
2.39.0


--
Andreas Schwab, schwab@xxxxxxxxxxxxxx
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