user: 提供的汇编代码用C语言表示会是什么样子:

```asm
<tc2fr>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x18(%rsp)
  xor    %eax,%eax
  test   %rdi,%rdi
  je     L161
  mov    %rdi,%rbx
  movb   $0x0,0x15(%rsp)
  movb   $0x0,0x16(%rsp)
  movb   $0x0,0x17(%rsp)
  jmp    L208
L252:
  add    $0x1,%rbx
L208:
  movsbl (%rbx),%edi
  call   <isspace@plt>
  mov    %rax,%r12
  test   %rax,%rax
  jne    L252
  mov    $0x0,%ebp
  lea    0x15(%rsp),%r14
  jmp    L151
L28:
  cmpb   $0x3a,0x1(%rbx)
  jne    L101
  mov    $0x1,%eax
  mov    $0x0,%r13d
  jmp    L34
L101:
  mov    $0x1,%eax
  jmp    L76
L209:
  mov    $0x0,%eax
L76:
  test   %eax,%eax
  jne    L156
  lea    -0x1(%rbp),%eax
  mov    $0x1,%r13d
L119:
  test   %r13d,%r13d
  jne    L14
  lea    0x1(%rax),%ebp
  cmp    $0x2,%ebp
  jg     L19
  test   %ebp,%ebp
  jle    L151
  cmpb   $0x3a,(%rbx)
  jne    L14
  add    $0x1,%rbx
L151:
  movsbl (%rbx),%edi
  call   <isdigit@plt>
  test   %rax,%rax
  je     L209
  movzbl (%rbx),%eax
  mov    %al,0x15(%rsp)
  movsbl 0x1(%rbx),%edi
  call   <isdigit@plt>
  test   %rax,%rax
  je     L28
  movzbl 0x1(%rbx),%eax
  mov    %al,0x16(%rsp)
  mov    $0x2,%eax
  mov    $0x0,%r13d
L34:
  movslq %eax,%r15
  movb   $0x0,0x15(%rsp,%r15,1)
  mov    %r14,%rdi
  call   <atoi@plt>
  mov    %eax,%edx
  movslq %ebp,%rax
  mov    %edx,0x8(%rsp,%rax,4)
  add    %r15,%rbx
  mov    %ebp,%eax
  jmp    L119
L156:
  mov    $0x1,%r13d
  jmp    L34
L19:
  mov    %ebp,%eax
L14:
  cmp    $0x3,%eax
  je     L163
  cmp    $0x1,%eax
  je     L228
  cmp    $0x2,%eax
  je     L163
  test   %eax,%eax
  jne    L196
  mov    0x8(%rsp),%ecx
  mov    %eax,%edx
L27:
  imul   $0x3c,%eax,%eax
  add    %edx,%eax
  imul   $0x4b,%eax,%eax
  add    %ecx,%eax
  movslq %eax,%r12
  cmp    $0x3b,%edx
  jg     L36
  cmp    $0x4a,%ecx
  jg     L36
L196:
  mov    0x18(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L98
  mov    %r12,%rax
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L228:
  mov    0x8(%rsp),%edx
  mov    0xc(%rsp),%ecx
  mov    $0x0,%eax
  jmp    L27
L163:
  mov    0x8(%rsp),%eax
  mov    0xc(%rsp),%edx
  mov    0x10(%rsp),%ecx
  jmp    L27
L36:
  mov    $0xffffffffffffffff,%r12
  jmp    L196
L161:
  mov    $0xffffffffffffffff,%r12
  jmp    L196
L98:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
long tc2fr(const char *tc) {
  int minutes = 0;
  int seconds = 0;
  int frames = 0;
  long totalframes = 0;
  char tmp[2 + 1];
  int nums[3];
  int n = 0;
  int i = 0;
  int last_was_colon = 0;
  int stop = 0;
  if (tc == NULL)
    return -1;
  for (i = 0; i <= 2; i++)
    tmp[i] = '\0';
  while (isspace(*tc))
    tc++;
  for (n = 0; n < 3; n++) {
    if (n > 0) {
      if (tc[0] != ':') {
        --n;
        break;
      } else
        tc++;
    }
    for (i = 0; i < 2; i++) {
      if (isdigit(tc[i])) {
        tmp[i] = tc[i];
        last_was_colon = 0;
      } else if (tc[i] == ':') {
        if (i == 0)
          stop = 1;
        break;
      } else {
        stop = 1;
        break;
      }
    }
    if (i != 0) {
      tmp[i] = '\0';
      nums[n] = atoi(tmp);
      tc = &tc[i];
    } else
      --n;
    if (stop)
      break;
  }
  if (n == 3)
    --n;
  frames = seconds = minutes = 0;
  switch (n) {
  case 0:
    frames = nums[0];
    break;
  case 1:
    seconds = nums[0];
    frames = nums[1];
    break;
  case 2:
    minutes = nums[0];
    seconds = nums[1];
    frames = nums[2];
    break;
  }
  totalframes = ((60 * minutes) + seconds) * 75 + frames;
  if (seconds > 59 || frames > 74)
    return -1;
  return totalframes;
}
```