diff options
Diffstat (limited to 'sys/lib/libkern/arch/i386/memchr.S')
| -rw-r--r-- | sys/lib/libkern/arch/i386/memchr.S | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/sys/lib/libkern/arch/i386/memchr.S b/sys/lib/libkern/arch/i386/memchr.S new file mode 100644 index 00000000000..43f7a91e0a1 --- /dev/null +++ b/sys/lib/libkern/arch/i386/memchr.S @@ -0,0 +1,27 @@ +/* $OpenBSD: memchr.S,v 1.1 1997/11/04 19:08:06 chuck Exp $ */ + +/* + * Written by J.T. Conklin <jtc@netbsd.org>. + * Public domain. + */ + +#include <machine/asm.h> + +ENTRY(memchr) + pushl %edi + movl 8(%esp),%edi /* string address */ + movl 12(%esp),%eax /* set character to search for */ + movl 16(%esp),%ecx /* set length of search */ + testl %ecx,%ecx /* test for len == 0 */ + jz L1 + cld /* set search forward */ + repne /* search! */ + scasb + jne L1 /* scan failed, return null */ + leal -1(%edi),%eax /* adjust result of scan */ + popl %edi + ret + .align 2,0x90 +L1: xorl %eax,%eax + popl %edi + ret |