user: 请将这段汇编代码片段转换成等效的C代码:

```asm
<split>:
  endbr64
  push   %rbx
  mov    %rsi,%r9
  movzbl (%rcx),%esi
  mov    %edx,%r8d
  mov    %rdi,%rax
  movzbl (%rdi),%edx
  test   %sil,%sil
  je     L190
  xor    %r10d,%r10d
  test   %dl,%dl
  je     L22
  movzbl 0x1(%rcx),%edi
  test   %dil,%dil
  jne    L180
  mov    %r8d,%ecx
  mov    %rax,(%r9)
  lea    0x8(%r9),%rdi
  sub    $0x1,%ecx
  jne    L489
  jmp    L343
  xchg   %ax,%ax
L230:
  test   %dl,%dl
  je     L473
L489:
  movzbl (%rax),%edx
  add    $0x1,%rax
  cmp    %dl,%sil
  jne    L230
  add    $0x8,%rdi
  movb   $0x0,-0x1(%rax)
  mov    %rax,-0x8(%rdi)
  sub    $0x1,%ecx
  jne    L489
L343:
  mov    %r8d,%r10d
  nopl   0x0(%rax,%rax,1)
L377:
  movzbl (%rax),%edx
  add    $0x1,%rax
  cmp    %dl,%sil
  je     L77
  test   %dl,%dl
  jne    L377
L22:
  mov    %r10d,%eax
  pop    %rbx
  ret
  nopl   0x0(%rax)
L413:
  mov    %rcx,%rax
L190:
  movzbl (%rax),%edx
  lea    0x1(%rax),%rcx
  cmp    $0x9,%dl
  je     L413
  cmp    $0x20,%dl
  je     L413
  xor    %r10d,%r10d
  test   %dl,%dl
  je     L22
  mov    $0x9,%edi
  mov    $0x1,%ebx
  mov    $0x20,%esi
L47:
  mov    %r8d,%r11d
L7:
  add    $0x8,%r9
  mov    %r11d,%r10d
  mov    %rax,%rcx
  sub    $0x1,%r11d
  mov    %rax,-0x8(%r9)
  jmp    L154
  nopl   0x0(%rax)
L435:
  cmp    %sil,%dl
  je     L249
  test   %dl,%dl
  je     L366
L154:
  movzbl (%rcx),%edx
  add    $0x1,%rcx
  cmp    %dil,%dl
  jne    L435
L249:
  test   %r11d,%r11d
  je     L474
  movb   $0x0,-0x1(%rcx)
  mov    %rcx,%rax
L416:
  movzbl (%rax),%edx
  lea    0x1(%rax),%rcx
  cmp    %sil,%dl
  je     L44
  cmp    %dil,%dl
  jne    L7
L44:
  mov    %rcx,%rax
  jmp    L416
  nopl   0x0(%rax,%rax,1)
L473:
  sub    %ecx,%r8d
  pop    %rbx
  mov    %r8d,%r10d
  mov    %r10d,%eax
  ret
  nopl   0x0(%rax,%rax,1)
L366:
  test   %ebx,%ebx
  je     L294
  cmpb   $0x0,(%rax)
  cmove  %r10d,%r11d
L294:
  sub    %r11d,%r8d
  pop    %rbx
  mov    %r8d,%r10d
  mov    %r10d,%eax
  ret
L180:
  cmpb   $0x0,0x2(%rcx)
  je     L18
L274:
  cmp    %r8d,%r10d
  jge    L382
  mov    %rax,(%r9)
  add    $0x8,%r9
L382:
  movzbl (%rax),%edi
  add    $0x1,%r10d
  lea    0x1(%rax),%rsi
  test   %dil,%dil
  je     L22
  nopl   0x0(%rax,%rax,1)
L134:
  mov    %rcx,%rax
L247:
  movzbl (%rax),%edx
  add    $0x1,%rax
  test   %dl,%dl
  je     L262
  cmp    %dil,%dl
  jne    L247
  cmp    %r10d,%r8d
  jle    L85
  movb   $0x0,-0x1(%rsi)
  nopl   0x0(%rax)
L85:
  mov    %rsi,%rax
  movzbl (%rsi),%r11d
  add    $0x1,%rsi
  mov    %rcx,%rdx
L107:
  movzbl (%rdx),%edi
  add    $0x1,%rdx
  test   %dil,%dil
  je     L274
  cmp    %dil,%r11b
  je     L85
  jmp    L107
  nopl   0x0(%rax)
L262:
  movzbl (%rsi),%edi
  add    $0x1,%rsi
  test   %dil,%dil
  jne    L134
  mov    %r10d,%eax
  pop    %rbx
  ret
  nopl   0x0(%rax)
L77:
  add    $0x1,%r10d
  jmp    L377
L474:
  mov    %r8d,%r10d
  test   %dl,%dl
  je     L237
L255:
  movzbl (%rcx),%eax
  lea    0x1(%rcx),%rdx
  cmp    %dil,%al
  je     L369
  cmp    %sil,%al
  je     L369
  add    $0x1,%r10d
  mov    %rdx,%rcx
  test   %al,%al
  je     L237
L15:
  cmp    %sil,%al
  je     L255
  cmp    %dil,%al
  je     L255
  movzbl (%rdx),%eax
  add    $0x1,%rdx
  mov    %rdx,%rcx
  test   %al,%al
  jne    L15
L237:
  sub    $0x1,%rcx
  test   %ebx,%ebx
  je     L22
L176:
  movzbl -0x1(%rcx),%eax
  lea    -0x1(%rcx),%rdx
  cmp    %dil,%al
  je     L160
  cmp    %sil,%al
  je     L160
  cmpb   $0x0,(%rcx)
  je     L22
  add    $0x1,%r8d
  cmp    %r10d,%r8d
  jne    L408
  movb   $0x0,(%rcx)
L408:
  sub    $0x1,%r10d
  jmp    L22
L369:
  mov    %rdx,%rcx
  jmp    L255
L160:
  mov    %rdx,%rcx
  jmp    L176
L18:
  xor    %ebx,%ebx
  jmp    L47
```

assistant: ```c
int split(string, fields, nfields, sep)
char *string;
char *fields[];
int nfields;
char *sep;
{
  char *p = string;
  char c;
  char sepc = sep[0];
  char sepc2;
  int fn;
  char **fp = fields;
  char *sepp;
  int trimtrail;
  if (sepc == '\0') {
    while ((c = *p++) == ' ' || c == '\t')
      continue;
    p--;
    trimtrail = 1;
    sep = (char *)" \t";
    sepc = ' ';
  } else
    trimtrail = 0;
  sepc2 = sep[1];
  if (*p == '\0')
    return (0);
  if (sepc2 == '\0') {
    fn = nfields;
    for (;;) {
      *fp++ = p;
      fn--;
      if (fn == 0)
        break;
      while ((c = *p++) != sepc)
        if (c == '\0')
          return (nfields - fn);
      *(p - 1) = '\0';
    }
    fn = nfields;
    for (;;) {
      while ((c = *p++) != sepc)
        if (c == '\0')
          return (fn);
      fn++;
    }
  }
  if (sep[2] == '\0') {
    fn = nfields;
    for (;;) {
      *fp++ = p;
      fn--;
      while ((c = *p++) != sepc && c != sepc2)
        if (c == '\0') {
          if (trimtrail && **(fp - 1) == '\0')
            fn++;
          return (nfields - fn);
        }
      if (fn == 0)
        break;
      *(p - 1) = '\0';
      while ((c = *p++) == sepc || c == sepc2)
        continue;
      p--;
    }
    fn = nfields;
    while (c != '\0') {
      while ((c = *p++) == sepc || c == sepc2)
        continue;
      p--;
      fn++;
      while ((c = *p++) != '\0' && c != sepc && c != sepc2)
        continue;
    }
    if (trimtrail) {
      p--;
      while ((c = *--p) == sepc || c == sepc2)
        continue;
      p++;
      if (*p != '\0') {
        if (fn == nfields + 1)
          *p = '\0';
        fn--;
      }
    }
    return (fn);
  }
  fn = 0;
  for (;;) {
    if (fn < nfields)
      *fp++ = p;
    fn++;
    for (;;) {
      c = *p++;
      if (c == '\0')
        return (fn);
      sepp = sep;
      while ((sepc = *sepp++) != '\0' && sepc != c)
        continue;
      if (sepc != '\0')
        break;
    }
    if (fn < nfields)
      *(p - 1) = '\0';
    for (;;) {
      c = *p++;
      sepp = sep;
      while ((sepc = *sepp++) != '\0' && sepc != c)
        continue;
      if (sepc == '\0')
        break;
    }
    p--;
  }
}
```