面倒見てもらえないのか…

jun@debian /tmp
$ cat tmp.c
int f(int o)
{
  return (o & 6) == 6 && (o & 8) == 0;
}
jun@debian /tmp
$ gcc -O3 -S -o - tmp.c
        .file   "tmp.c"
        .text
        .p2align 4,,15
.globl f
        .type   f, @function
f:
        pushl   %ebp
        movl    %esp, %ebp
        movl    8(%ebp), %edx
        movl    %edx, %eax
        andl    $6, %eax        ; <---
        cmpl    $6, %eax
        je      .L9
.L2:
        popl    %ebp
        xorl    %eax, %eax
        ret
        .p2align 4,,7
.L9:
        testb   $8, %dl         ; <---
        movl    $1, %eax
        jne     .L2