user: What is the c source code of the assembly code below:

```asm
<rotate>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x28(%rbp)
  mov    %esi,-0x2c(%rbp)
  movl   $0x0,-0x14(%rbp)
  jmp    L19
L31:
  movl   $0x0,-0x10(%rbp)
  jmp    L10
L1:
  mov    -0x14(%rbp),%eax
  mov    %eax,-0xc(%rbp)
  mov    -0x2c(%rbp),%eax
  sub    $0x1,%eax
  sub    -0x14(%rbp),%eax
  mov    %eax,-0x8(%rbp)
  mov    -0xc(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0xc(%rbp),%ecx
  mov    -0x10(%rbp),%eax
  add    %ecx,%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x4(%rbp)
  mov    -0xc(%rbp),%edx
  mov    -0x10(%rbp),%eax
  add    %edx,%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0x8(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    -0xc(%rbp),%edx
  movslq %edx,%rdx
  lea    0x0(,%rdx,8),%rcx
  mov    -0x28(%rbp),%rdx
  add    %rcx,%rdx
  mov    (%rdx),%rcx
  mov    -0xc(%rbp),%esi
  mov    -0x10(%rbp),%edx
  add    %esi,%edx
  movslq %edx,%rdx
  shl    $0x2,%rdx
  add    %rcx,%rdx
  mov    (%rax),%eax
  mov    %eax,(%rdx)
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0x8(%rbp),%eax
  sub    -0x10(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    -0xc(%rbp),%ecx
  mov    -0x10(%rbp),%edx
  add    %ecx,%edx
  movslq %edx,%rdx
  lea    0x0(,%rdx,8),%rcx
  mov    -0x28(%rbp),%rdx
  add    %rcx,%rdx
  mov    (%rdx),%rcx
  mov    -0x8(%rbp),%edx
  movslq %edx,%rdx
  shl    $0x2,%rdx
  add    %rcx,%rdx
  mov    (%rax),%eax
  mov    %eax,(%rdx)
  mov    -0x8(%rbp),%eax
  sub    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0xc(%rbp),%eax
  cltq
  shl    $0x2,%rax
  lea    (%rdx,%rax,1),%rcx
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0x8(%rbp),%eax
  sub    -0x10(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rax,%rdx
  mov    (%rcx),%eax
  mov    %eax,(%rdx)
  mov    -0x8(%rbp),%eax
  sub    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0xc(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rax,%rdx
  mov    -0x4(%rbp),%eax
  mov    %eax,(%rdx)
  addl   $0x1,-0x10(%rbp)
L10:
  mov    -0x2c(%rbp),%eax
  sub    $0x1,%eax
  sub    -0x14(%rbp),%eax
  cmp    %eax,-0x10(%rbp)
  jl     L1
  addl   $0x1,-0x14(%rbp)
L19:
  mov    -0x2c(%rbp),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  cmp    %eax,-0x14(%rbp)
  jl     L31
  nop
  nop
  pop    %rbp
  ret
```

assistant: ```c
void rotate(int **matrix, int n) {
  int layer;
  int first, last, shift;
  int tmp;
  for (layer = 0; layer < n / 2; ++layer) {
    for (shift = 0; shift < n - 1 - layer; ++shift) {
      first = layer;
      last = n - 1 - layer;
      tmp = matrix[first][first + shift];
      matrix[first][first + shift] = matrix[first + shift][last];
      matrix[first + shift][last] = matrix[last][last - shift];
      matrix[last][last - shift] = matrix[last - shift][first];
      matrix[last - shift][first] = tmp;
    }
  }
}
```