user: Translate the below assembly code into C programming language:

```asm
<gendifferentialtime>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x18(%rbp)
  mov    %rsi,-0x20(%rbp)
  mov    %edx,-0x24(%rbp)
  mov    -0x20(%rbp),%rax
  add    $0xb,%rax
  movzbl (%rax),%eax
  shr    $0x4,%al
  movzbl %al,%eax
  imul   $0x64,%eax,%ecx
  mov    -0x20(%rbp),%rax
  add    $0xb,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  and    $0xf,%eax
  mov    %eax,%edx
  mov    %edx,%eax
  shl    $0x2,%eax
  add    %edx,%eax
  add    %eax,%eax
  lea    (%rcx,%rax,1),%edx
  mov    -0x20(%rbp),%rax
  add    $0xa,%rax
  movzbl (%rax),%eax
  shr    $0x4,%al
  movzbl %al,%eax
  add    %edx,%eax
  mov    %eax,-0x8(%rbp)
  mov    -0x20(%rbp),%rax
  add    $0xa,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  and    $0xf,%eax
  imul   $0x2710,%eax,%edx
  mov    -0x20(%rbp),%rax
  add    $0x9,%rax
  movzbl (%rax),%eax
  shr    $0x4,%al
  movzbl %al,%eax
  imul   $0x3e8,%eax,%eax
  add    %eax,%edx
  mov    -0x20(%rbp),%rax
  add    $0x9,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  and    $0xf,%eax
  imul   $0x64,%eax,%eax
  lea    (%rdx,%rax,1),%ecx
  mov    -0x20(%rbp),%rax
  add    $0x8,%rax
  movzbl (%rax),%eax
  shr    $0x4,%al
  movzbl %al,%edx
  mov    %edx,%eax
  shl    $0x2,%eax
  add    %edx,%eax
  add    %eax,%eax
  lea    (%rcx,%rax,1),%edx
  mov    -0x20(%rbp),%rax
  add    $0x8,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  and    $0xf,%eax
  add    %edx,%eax
  mov    %eax,-0x4(%rbp)
  mov    -0x24(%rbp),%eax
  add    %eax,-0x4(%rbp)
  cmpl   $0x0,-0x4(%rbp)
  jns    L20
  addl   $0x15180,-0x4(%rbp)
  subl   $0x1,-0x8(%rbp)
  cmpl   $0x0,-0x8(%rbp)
  jns    L31
  addl   $0x3e8,-0x8(%rbp)
  jmp    L31
L20:
  cmpl   $0x1517f,-0x4(%rbp)
  jle    L31
  subl   $0x15180,-0x4(%rbp)
  addl   $0x1,-0x8(%rbp)
  cmpl   $0x3e7,-0x8(%rbp)
  jle    L31
  subl   $0x3e8,-0x8(%rbp)
L31:
  mov    -0x4(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%esi
  sar    $0x1f,%esi
  sub    %esi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    %ecx,%edx
  mov    -0x18(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x4(%rbp)
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%esi
  mov    -0x4(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%edi
  sar    $0x1f,%edi
  sub    %edi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x4,%eax
  lea    (%rsi,%rax,1),%edx
  mov    -0x18(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x4(%rbp)
  mov    -0x4(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%esi
  sar    $0x1f,%esi
  sub    %esi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x4(%rbp)
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%esi
  mov    -0x4(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%edi
  sar    $0x1f,%edi
  sub    %edi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x4,%eax
  mov    %eax,%edx
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  add    %esi,%edx
  mov    %dl,(%rax)
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x4(%rbp)
  mov    -0x4(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%esi
  sar    $0x1f,%esi
  sub    %esi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    -0x18(%rbp),%rax
  add    $0x2,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x18(%rbp),%rax
  add    $0x2,%rax
  movzbl (%rax),%esi
  mov    -0x8(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%edi
  sar    $0x1f,%edi
  sub    %edi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x4,%eax
  mov    %eax,%edx
  mov    -0x18(%rbp),%rax
  add    $0x2,%rax
  add    %esi,%edx
  mov    %dl,(%rax)
  mov    -0x8(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x8(%rbp)
  mov    -0x8(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%esi
  sar    $0x1f,%esi
  sub    %esi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    -0x18(%rbp),%rax
  add    $0x3,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x8(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    $0x2,%edx
  sar    $0x1f,%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  sub    %ecx,%eax
  mov    %eax,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  add    $0x3,%rax
  movzbl (%rax),%esi
  mov    -0x8(%rbp),%edx
  movslq %edx,%rax
  imul   $0x66666667,%rax,%rax
  shr    $0x20,%rax
  sar    $0x2,%eax
  mov    %edx,%edi
  sar    $0x1f,%edi
  sub    %edi,%eax
  mov    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x2,%eax
  add    %ecx,%eax
  add    %eax,%eax
  mov    %edx,%ecx
  sub    %eax,%ecx
  mov    %ecx,%eax
  shl    $0x4,%eax
  mov    %eax,%edx
  mov    -0x18(%rbp),%rax
  add    $0x3,%rax
  add    %esi,%edx
  mov    %dl,(%rax)
  nop
  pop    %rbp
  ret
```

assistant: ```c
void gendifferentialtime(unsigned char timebytes[4], const unsigned char *cur, int dt) {
  int newday;
  int newsec;
  newday = (cur[11] >> 4) * 100 + (cur[11] & 0x0F) * 10 + (cur[10] >> 4);
  newsec = (cur[10] & 0x0F) * 10000 + (cur[9] >> 4) * 1000 + (cur[9] & 0x0F) * 100 + (cur[8] >> 4) * 10 + (cur[8] & 0x0F);
  newsec += dt;
  if (newsec < 0) {
    newsec += 86400;
    --newday;
    if (newday < 0) {
      newday += 1000;
    }
  } else if (newsec >= 86400) {
    newsec -= 86400;
    ++newday;
    if (newday >= 1000) {
      newday -= 1000;
    }
  }
  timebytes[0] = newsec % 10;
  newsec /= 10;
  timebytes[0] += (newsec % 10) << 4;
  newsec /= 10;
  timebytes[1] = newsec % 10;
  newsec /= 10;
  timebytes[1] += (newsec % 10) << 4;
  newsec /= 10;
  timebytes[2] = newsec % 10;
  timebytes[2] += (newday % 10) << 4;
  newday /= 10;
  timebytes[3] = newday % 10;
  newday /= 10;
  timebytes[3] += (newday % 10) << 4;
}
```