user: 请显示与下面列出的汇编代码相匹配的C语言实现：

```asm
<strtoxl>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %rdi,0x18(%rsp)
  mov    %rsi,0x10(%rsp)
  mov    %edx,%r14d
  mov    %ecx,%r13d
  lea    0x1(%rdi),%rbp
  movzbl (%rdi),%ebx
  jmp    L262
L307:
  add    $0x1,%rbp
  movzbl -0x1(%rbp),%ebx
L262:
  movsbl %bl,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L307
  cmp    $0x2d,%bl
  je     L299
  cmp    $0x2b,%bl
  je     L81
L61:
  cmp    $0x1,%r14d
  je     L415
  cmp    $0x24,%r14d
  ja     L415
  test   %r14d,%r14d
  jne    L401
  mov    $0xa,%r14d
  cmp    $0x30,%bl
  je     L133
L195:
  mov    D42(%rip),%rax
  mov    (%rax),%eax
  cltd
  idiv   %r14d
  movslq %eax,%r15
  mov    $0x0,%r12d
  movslq %r14d,%rax
  mov    %rax,0x8(%rsp)
  jmp    L408
L299:
  or     $0x2,%r13d
  movzbl 0x0(%rbp),%ebx
  lea    0x1(%rbp),%rbp
  jmp    L61
L81:
  movzbl 0x0(%rbp),%ebx
  lea    0x1(%rbp),%rbp
  jmp    L61
L415:
  mov    $0x0,%r12d
  mov    0x10(%rsp),%rax
  test   %rax,%rax
  je     L261
  mov    0x18(%rsp),%rsi
  mov    %rsi,(%rax)
L261:
  mov    %r12,%rax
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L133:
  movzbl 0x0(%rbp),%eax
  and    $0xffffffdf,%eax
  mov    $0x8,%r14d
  cmp    $0x58,%al
  jne    L195
L20:
  movzbl 0x1(%rbp),%ebx
  lea    0x2(%rbp),%rbp
  mov    $0x10,%r14d
  jmp    L195
L401:
  cmp    $0x10,%r14d
  jne    L195
  cmp    $0x30,%bl
  jne    L195
  movzbl 0x0(%rbp),%eax
  and    $0xffffffdf,%eax
  cmp    $0x58,%al
  jne    L195
  jmp    L20
L230:
  mov    %ebx,%edi
  call   <isalpha@plt>
  test   %rax,%rax
  je     L229
  mov    %ebx,%edi
  call   <toupper@plt>
  movsbl %al,%ebx
  sub    $0x37,%ebx
  jmp    L325
L3:
  mov    %ebx,%ecx
  mov    D42(%rip),%rax
  mov    (%rax),%eax
  cltd
  idiv   %r14d
  movslq %edx,%rdx
  cmp    %rdx,%rcx
  ja     L336
L399:
  or     $0x8,%r13d
  imul   0x8(%rsp),%r12
  mov    %ebx,%ebx
  add    %rbx,%r12
L284:
  add    $0x1,%rbp
  movzbl -0x1(%rbp),%ebx
L408:
  movsbl %bl,%ebx
  mov    %ebx,%edi
  call   <isdigit@plt>
  test   %rax,%rax
  je     L230
  sub    $0x30,%ebx
L325:
  cmp    %ebx,%r14d
  jbe    L229
  cmp    %r15,%r12
  jb     L399
  je     L3
L336:
  or     $0xc,%r13d
  jmp    L284
L229:
  sub    $0x1,%rbp
  test   $0x8,%r13b
  jne    L250
  mov    $0x0,%r12d
  cmpq   $0x0,0x10(%rsp)
  je     L123
L328:
  mov    0x10(%rsp),%rax
  mov    0x18(%rsp),%rsi
  mov    %rsi,(%rax)
L123:
  test   $0x2,%r13b
  je     L261
L420:
  neg    %r12
  jmp    L261
L250:
  test   $0x4,%r13b
  jne    L233
  test   $0x1,%r13b
  jne    L370
  test   $0x2,%r13b
  je     L202
  mov    D41(%rip),%rax
  cmp    %r12,(%rax)
  jbe    L176
L236:
  mov    D79(%rip),%rax
  mov    (%rax),%edx
  mov    D5(%rip),%rax
  mov    %edx,(%rax)
L410:
  test   $0x2,%r13b
  je     L149
  mov    D41(%rip),%rax
  mov    (%rax),%r12
L176:
  mov    %rbp,0x18(%rsp)
  cmpq   $0x0,0x10(%rsp)
  jne    L328
  jmp    L420
L202:
  mov    D100(%rip),%rax
  cmp    %r12,(%rax)
  jb     L236
  jmp    L114
L233:
  mov    D79(%rip),%rax
  mov    (%rax),%edx
  mov    D5(%rip),%rax
  mov    %edx,(%rax)
  test   $0x1,%r13b
  je     L410
  mov    D42(%rip),%rax
  movslq (%rax),%r12
L370:
  cmpq   $0x0,0x10(%rsp)
  je     L123
  mov    %rbp,0x18(%rsp)
  jmp    L328
L149:
  mov    D100(%rip),%rax
  mov    (%rax),%r12
L114:
  mov    %rbp,0x18(%rsp)
  cmpq   $0x0,0x10(%rsp)
  jne    L328
  jmp    L261
```

assistant: ```c
unsigned long strtoxl(const char *nptr, char **endptr, int ibase, int flags) {
  const char *p;
  char c;
  unsigned long number;
  unsigned digval;
  unsigned long maxval;
  p = (const char *)nptr;
  number = 0;
  c = *p++;
  while (isspace(c))
    c = *p++;
  if (c == '-') {
    flags |= 2;
    c = *p++;
  } else if (c == '+') {
    c = *p++;
  }
  if (ibase < 0 || ibase == 1 || ibase > 36) {
    if (endptr)
      *endptr = (char *)nptr;
    return 0L;
  } else if (ibase == 0) {
    if (c != '0') {
      ibase = 10;
    } else if (*p == 'x' || *p == 'X') {
      ibase = 16;
    } else {
      ibase = 8;
    }
  }
  if (ibase == 16) {
    if (c == '0' && (*p == 'x' || *p == 'X')) {
      ++p;
      c = *p++;
    }
  }
  maxval = UINT32_MAX / ibase;
  for (;;) {
    if (isdigit(c)) {
      digval = c - '0';
    } else if (isalpha(c)) {
      digval = toupper(c) - 'A' + 10;
    } else {
      break;
    }
    if (digval >= (unsigned)ibase)
      break;
    flags |= 8;
    if (number < maxval || (number == maxval && (unsigned long)digval <= UINT32_MAX % ibase)) {
      number = number * ibase + digval;
    } else {
      flags |= 4;
    }
    c = *p++;
  }
  --p;
  if (!(flags & 8)) {
    if (endptr)
      p = nptr;
    number = 0;
  } else if ((flags & 4) || (!(flags & 1) && (((flags & 2) && (number < INT32_MIN)) || (!(flags & 2) && (number > INT32_MAX))))) {
    errno = ERANGE;
    if (flags & 1) {
      number = UINT32_MAX;
    } else if (flags & 2) {
      number = INT32_MIN;
    } else {
      number = INT32_MAX;
    }
  }
  if (endptr)
    *endptr = (char *)p;
  if (flags & 2)
    number = (unsigned long)(-(long)number);
  return number;
}
```