user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<is_valid_email_address>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x20,%rsp
  mov    %rdi,-0x18(%rbp)
  cmpq   $0x0,-0x18(%rbp)
  je     L314
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L202
L314:
  mov    $0x0,%eax
  jmp    L132
L202:
  movq   $0x0,-0x8(%rbp)
  mov    -0x18(%rbp),%rax
  mov    %rax,-0x10(%rbp)
  jmp    L142
L320:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x20,%al
  jbe    L342
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x7e,%al
  ja     L342
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x5c,%al
  je     L342
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x27,%al
  je     L342
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x22,%al
  jne    L455
L342:
  mov    $0x0,%eax
  jmp    L132
L455:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  jne    L71
  cmpq   $0x0,-0x8(%rbp)
  je     L398
  mov    $0x0,%eax
  jmp    L132
L398:
  mov    -0x10(%rbp),%rax
  mov    %rax,-0x8(%rbp)
L71:
  addq   $0x1,-0x10(%rbp)
L142:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L320
  cmpq   $0x0,-0x8(%rbp)
  jne    L328
  mov    $0x0,%eax
  jmp    L132
L328:
  mov    -0x8(%rbp),%rax
  cmp    -0x18(%rbp),%rax
  je     L1
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L27
L1:
  mov    $0x0,%eax
  jmp    L132
L27:
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  mov    %rax,-0x10(%rbp)
  jmp    L215
L498:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <isalnum@plt>
  test   %rax,%rax
  jne    L81
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2d,%al
  je     L81
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x5f,%al
  je     L81
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  je     L81
  mov    $0x0,%eax
  jmp    L132
L81:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  jne    L20
  mov    -0x10(%rbp),%rax
  sub    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  je     L131
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L131
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  jne    L20
L131:
  mov    $0x0,%eax
  jmp    L132
L20:
  addq   $0x1,-0x10(%rbp)
L215:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L498
  mov    -0x18(%rbp),%rax
  mov    %rax,-0x10(%rbp)
  jmp    L315
L222:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  jne    L493
  mov    -0x10(%rbp),%rax
  cmp    -0x18(%rbp),%rax
  je     L449
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  je     L449
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  jne    L268
L449:
  mov    $0x0,%eax
  jmp    L132
L493:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <isalnum@plt>
  test   %rax,%rax
  jne    L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x21,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x23,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2b,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2d,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x3d,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x3f,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x5e,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x5f,%al
  je     L268
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x7e,%al
  je     L268
  mov    $0x0,%eax
  jmp    L132
L268:
  addq   $0x1,-0x10(%rbp)
L315:
  mov    -0x10(%rbp),%rax
  cmp    -0x8(%rbp),%rax
  jb     L222
  mov    $0x1,%eax
L132:
  leave
  ret
```

assistant: ```c
int is_valid_email_address(const unsigned char *email_address) {
  if (!email_address || !*email_address)
    return 0;
  const unsigned char *p;
  const unsigned char *at_ptr = 0;
  for (p = email_address; *p; ++p) {
    if (*p <= ' ' || *p >= 127 || *p == '\\' || *p == '\'' || *p == '\"')
      return 0;
    if (*p == '@') {
      if (at_ptr)
        return 0;
      at_ptr = p;
    }
  }
  if (!at_ptr)
    return 0;
  if (at_ptr == email_address || !at_ptr[1])
    return 0;
  for (p = at_ptr + 1; *p; ++p) {
    if (!isalnum(*p) && *p != '-' && *p != '_' && *p != '.')
      return 0;
    if (*p == '.' && (p[-1] == '@' || !p[1] || p[1] == '.'))
      return 0;
  }
  for (p = email_address; p < at_ptr; ++p) {
    if (*p == '.') {
      if (p == email_address || p[1] == '@' || p[1] == '.')
        return 0;
    } else if (isalnum(*p)) {
    } else if (*p == '!' || *p == '#' || *p == '+' || *p == '-' || *p == '/' || *p == '=' || *p == '?' || *p == '^' || *p == '_' || *p == '~') {
    } else {
      return 0;
    }
  }
  return 1;
}
```