user: 这段汇编代码用C语言表示是什么样的:

```asm
<__add__>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r13
  push   %r12
  push   %rbx
  mov    %rdx,%rax
  mov    %ecx,%edx
  mov    %edx,%r12d
  sar    $0x3,%r12d
  mov    $0x0,%ebx
  and    $0x7,%edx
  mov    %edx,%r13d
  jmp    L15
L8:
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
L15:
  mov    %r12d,%edx
  lea    -0x1(%rdx),%r12d
  test   %edx,%edx
  jne    L8
  cmp    $0x7,%r13d
  ja     L1
  mov    %r13d,%edx
  lea    0x0(,%rdx,4),%rcx
  lea    D4(%rip),%rdx
  mov    (%rcx,%rdx,1),%edx
  movslq %edx,%rdx
  lea    D4(%rip),%rcx
  add    %rcx,%rdx
  notrack jmp *%rdx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rax,%rdx
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rdx)
  add    $0x1,%ebx
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdi,%rdx
  movsd  (%rdx),%xmm1
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rsi,%rdx
  movsd  (%rdx),%xmm0
  movslq %ebx,%rdx
  shl    $0x3,%rdx
  add    %rdx,%rax
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%rax)
  add    $0x1,%ebx
L1:
  nop
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %rbp
  ret
```

assistant: ```c
void __add__(dp1, dp2, out, len) register double *dp1, *dp2, *out;
register int len;
{
  register int i;
  register int j, k;
  i = len >> 3;
  j = 0;
  k = len & 7;
  while (i--) {
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
    out[j] = dp1[j] + dp2[j];
    j++;
  }
  switch (k) {
  case 7:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 6:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 5:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 4:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 3:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 2:
    out[j] = dp1[j] + dp2[j];
    j++;
  case 1:
    out[j] = dp1[j] + dp2[j];
    j++;
  }
}
```