user: 下面的汇编指令对应的C源代码是什么：

```asm
<merge_sort>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  mov    %rdi,%rbp
  push   %rbx
  sub    $0x28,%rsp
  cmp    $0x1,%esi
  jg     L14
  add    $0x28,%rsp
  mov    %rdi,%rax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax)
L14:
  mov    %esi,%r12d
  mov    %esi,%ebx
  sar    %r12d
  movslq %r12d,%rax
  lea    (%rdi,%rax,8),%r13
  cmp    $0x1,%r12d
  jne    L17
  sub    %r12d,%ebx
  cmp    $0x1,%ebx
  jg     L43
L65:
  add    $0x28,%rsp
  mov    %ebx,%ecx
  mov    %r12d,%edx
  mov    %r13,%rsi
  pop    %rbx
  mov    %rbp,%rdi
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  jmp    1050 <merge@plt>
  nop
L17:
  mov    %esi,%r14d
  sar    $0x2,%r14d
  movslq %r14d,%rax
  lea    (%rdi,%rax,8),%r15
  cmp    $0x1,%r14d
  je     L63
  mov    %esi,%edx
  sar    $0x3,%edx
  movslq %edx,%rax
  mov    %edx,%esi
  mov    %edx,0x8(%rsp)
  lea    (%rdi,%rax,8),%r8
  mov    %r8,0x10(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%edx
  mov    %r14d,%ecx
  mov    0x10(%rsp),%rdi
  mov    %rax,%rbp
  sub    %edx,%ecx
  mov    %edx,0xc(%rsp)
  mov    %ecx,%esi
  mov    %ecx,0x8(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%ecx
  mov    0xc(%rsp),%edx
  mov    %rbp,%rdi
  mov    %rax,%rsi
  call   <merge@plt>
  mov    %rax,%rbp
L63:
  mov    %r12d,%r8d
  sub    %r14d,%r8d
  cmp    $0x1,%r8d
  jle    L34
  mov    %r8d,%edx
  mov    %r15,%rdi
  mov    %r8d,0xc(%rsp)
  sar    %edx
  movslq %edx,%rax
  mov    %edx,%esi
  mov    %edx,0x8(%rsp)
  lea    (%r15,%rax,8),%r9
  mov    %r9,0x18(%rsp)
  call   <merge_sort>
  mov    0xc(%rsp),%r8d
  mov    0x8(%rsp),%edx
  mov    0x18(%rsp),%rdi
  mov    %rax,%r15
  mov    %r8d,%ecx
  mov    %r8d,0x10(%rsp)
  sub    %edx,%ecx
  mov    %edx,0xc(%rsp)
  mov    %ecx,%esi
  mov    %ecx,0x8(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%ecx
  mov    0xc(%rsp),%edx
  mov    %r15,%rdi
  mov    %rax,%rsi
  call   <merge@plt>
  mov    0x10(%rsp),%r8d
  mov    %rax,%r15
L34:
  mov    %rbp,%rdi
  mov    %r8d,%ecx
  mov    %r14d,%edx
  mov    %r15,%rsi
  call   <merge@plt>
  sub    %r12d,%ebx
  mov    %rax,%rbp
  cmp    $0x1,%ebx
  jle    L65
L43:
  mov    %ebx,%r14d
  sar    %r14d
  movslq %r14d,%rax
  lea    0x0(%r13,%rax,8),%r15
  cmp    $0x1,%r14d
  je     L72
  mov    %ebx,%edx
  mov    %r13,%rdi
  sar    $0x2,%edx
  movslq %edx,%rax
  mov    %edx,%esi
  mov    %edx,0x8(%rsp)
  lea    0x0(%r13,%rax,8),%r8
  mov    %r8,0x10(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%edx
  mov    %r14d,%ecx
  mov    0x10(%rsp),%rdi
  mov    %rax,%r13
  sub    %edx,%ecx
  mov    %edx,0xc(%rsp)
  mov    %ecx,%esi
  mov    %ecx,0x8(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%ecx
  mov    0xc(%rsp),%edx
  mov    %r13,%rdi
  mov    %rax,%rsi
  call   <merge@plt>
  mov    %rax,%r13
L72:
  mov    %ebx,%r8d
  sub    %r14d,%r8d
  cmp    $0x1,%r8d
  jle    L45
  mov    %r8d,%edx
  mov    %r15,%rdi
  mov    %r8d,0xc(%rsp)
  sar    %edx
  movslq %edx,%rax
  mov    %edx,%esi
  mov    %edx,0x8(%rsp)
  lea    (%r15,%rax,8),%r9
  mov    %r9,0x18(%rsp)
  call   <merge_sort>
  mov    0xc(%rsp),%r8d
  mov    0x8(%rsp),%edx
  mov    0x18(%rsp),%rdi
  mov    %rax,%r15
  mov    %r8d,%ecx
  mov    %r8d,0x10(%rsp)
  sub    %edx,%ecx
  mov    %edx,0xc(%rsp)
  mov    %ecx,%esi
  mov    %ecx,0x8(%rsp)
  call   <merge_sort>
  mov    0x8(%rsp),%ecx
  mov    0xc(%rsp),%edx
  mov    %r15,%rdi
  mov    %rax,%rsi
  call   <merge@plt>
  mov    0x10(%rsp),%r8d
  mov    %rax,%r15
L45:
  mov    %r13,%rdi
  mov    %r8d,%ecx
  mov    %r14d,%edx
  mov    %r15,%rsi
  call   <merge@plt>
  mov    %rax,%r13
  jmp    L65
```

assistant: ```c
long long *merge_sort(long long *arr, int size) {
  if (size > 1) {
    int middle = size / 2, i;
    long long *left, *right;
    left = arr;
    right = arr + middle;
    left = merge_sort(left, middle);
    right = merge_sort(right, size - middle);
    return merge(left, right, middle, size - middle);
  } else {
    return arr;
  }
}
```