diff options
| author |   millert <millert@openbsd.org> | 2000-06-16 19:56:53 +0000 |
|---|---|---|
| committer | millert <millert@openbsd.org> | 2000-06-16 19:56:53 +0000 |
| commit | b15d0beb3ec146d07c53b59363a3dc07c8e027d1 (patch) | |
| tree | 39aaa3d7a6ee32233f9924ead262794279c0cf0d /sys/lib/libkern/arch/i386/memcmp.S | |
| parent | undo latest problem. breaks the sparc. diff is too large, we are not debugging it for you (diff) | |
| download | wireguard-openbsd-b15d0beb3ec146d07c53b59363a3dc07c8e027d1.tar.xz wireguard-openbsd-b15d0beb3ec146d07c53b59363a3dc07c8e027d1.zip | |
Pull memcmp() into libkern. Also, use asm version of memset() on m68k.
Diffstat (limited to 'sys/lib/libkern/arch/i386/memcmp.S')
| -rw-r--r-- | sys/lib/libkern/arch/i386/memcmp.S | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/sys/lib/libkern/arch/i386/memcmp.S b/sys/lib/libkern/arch/i386/memcmp.S new file mode 100644 index 00000000000..4ad4fd46469 --- /dev/null +++ b/sys/lib/libkern/arch/i386/memcmp.S @@ -0,0 +1,44 @@ +/* $OpenBSD: memcmp.S,v 1.1 2000/06/16 19:56:54 millert Exp $ */ + +/* + * Written by J.T. Conklin <jtc@netbsd.org>. + * Public domain. + */ + +#include <machine/asm.h> + +ENTRY(memcmp) + pushl %edi + pushl %esi + movl 12(%esp),%edi + movl 16(%esp),%esi + cld /* set compare direction forward */ + + movl 20(%esp),%ecx /* compare by words */ + shrl $2,%ecx + repe + cmpsl + jne L5 /* do we match so far? */ + + movl 20(%esp),%ecx /* compare remainder by bytes */ + andl $3,%ecx + repe + cmpsb + jne L6 /* do we match? */ + + xorl %eax,%eax /* we match, return zero */ + popl %esi + popl %edi + ret + +L5: movl $4,%ecx /* We know that one of the next */ + subl %ecx,%edi /* four pairs of bytes do not */ + subl %ecx,%esi /* match. */ + repe + cmpsb +L6: movzbl -1(%edi),%eax /* Perform unsigned comparison */ + movzbl -1(%esi),%edx + subl %edx,%eax + popl %esi + popl %edi + ret |