9
10#if 0
11 RCSID("$NetBSD: memcmp.S,v 1.2 2003/07/26 19:24:39 salo Exp $")
12#endif
13
14ENTRY(memcmp)
15 cld /* set compare direction forward */
16 movq %rdx,%rcx /* compare by longs */
17 shrq $3,%rcx
18 repe
19 cmpsq
20 jne L5 /* do we match so far? */
21
22 movq %rdx,%rcx /* compare remainder by bytes */
23 andq $7,%rcx
24 repe
25 cmpsb
26 jne L6 /* do we match? */
27
28 xorl %eax,%eax /* we match, return zero */
29 ret
30
31L5: movl $8,%ecx /* We know that one of the next */
32 subq %rcx,%rdi /* eight pairs of bytes do not */
33 subq %rcx,%rsi /* match. */
34 repe
35 cmpsb
36L6: xorl %eax,%eax /* Perform unsigned comparison */
37 movb -1(%rdi),%al
38 xorl %edx,%edx
39 movb -1(%rsi),%dl
40 subl %edx,%eax
41 ret
| 9
10#if 0
11 RCSID("$NetBSD: memcmp.S,v 1.2 2003/07/26 19:24:39 salo Exp $")
12#endif
13
14ENTRY(memcmp)
15 cld /* set compare direction forward */
16 movq %rdx,%rcx /* compare by longs */
17 shrq $3,%rcx
18 repe
19 cmpsq
20 jne L5 /* do we match so far? */
21
22 movq %rdx,%rcx /* compare remainder by bytes */
23 andq $7,%rcx
24 repe
25 cmpsb
26 jne L6 /* do we match? */
27
28 xorl %eax,%eax /* we match, return zero */
29 ret
30
31L5: movl $8,%ecx /* We know that one of the next */
32 subq %rcx,%rdi /* eight pairs of bytes do not */
33 subq %rcx,%rsi /* match. */
34 repe
35 cmpsb
36L6: xorl %eax,%eax /* Perform unsigned comparison */
37 movb -1(%rdi),%al
38 xorl %edx,%edx
39 movb -1(%rsi),%dl
40 subl %edx,%eax
41 ret
|