user: 下面的汇编指令对应的C源代码是什么：

```asm
<strtol>:
  endbr64
  push   %r14
  push   %r13
  push   %r12
  mov    %rsi,%r12
  push   %rbp
  mov    %rdi,%rbp
  xor    %edi,%edi
  push   %rbx
  test   %rbp,%rbp
  mov    %edx,%ebx
  setne  %dil
  call   <assert@plt>
  mov    %rbp,%rcx
  nopl   (%rax)
L220:
  mov    %rcx,%rdx
  movzbl (%rcx),%esi
  add    $0x1,%rcx
  mov    %esi,%eax
  sub    $0x9,%eax
  cmp    $0x1,%al
  jbe    L220
  cmp    $0x20,%esi
  je     L220
  mov    %ebx,%eax
  and    $0xffffffef,%eax
  cmp    $0x2d,%esi
  je     L9
  cmp    $0x2b,%esi
  je     L237
  movslq %ebx,%r9
  test   %eax,%eax
  je     L157
L193:
  mov    D32(%rip),%rax
  xor    %r8d,%r8d
  mov    (%rax),%r11
  mov    %r11,%rax
  cqto
  idiv   %r9
  mov    %rax,%r10
  mov    D4(%rip),%rax
  mov    (%rax),%r13d
  xor    %eax,%eax
  jmp    L16
  nopl   0x0(%rax,%rax,1)
L182:
  cmp    $0xffffffff,%r8d
  je     L134
  cmp    %rax,%r10
  jl     L0
  cmp    %edi,%edx
  jge    L326
  cmp    %rax,%r10
  jne    L326
L0:
  mov    D38(%rip),%rax
  mov    $0xffffffff,%r8d
  mov    %r13d,(%rax)
  mov    %r11,%rax
L134:
  movzbl (%rcx),%esi
  add    $0x1,%rcx
L16:
  lea    -0x30(%rsi),%edi
  cmp    $0x9,%edi
  jbe    L121
  mov    %esi,%edi
  lea    -0x41(%rsi),%r14d
  and    $0xffffffdf,%edi
  sub    $0x41,%edi
  cmp    $0x19,%edi
  ja     L174
  cmp    $0x1a,%r14d
  mov    %esi,%edi
  sbb    %r14d,%r14d
  and    $0xffffffe0,%r14d
  add    $0x57,%r14d
  sub    %r14d,%edi
L121:
  cmp    %edi,%ebx
  jg     L182
L174:
  test   %r12,%r12
  je     L185
  sub    $0x1,%rcx
  test   %r8d,%r8d
  cmovne %rcx,%rbp
  mov    %rbp,(%r12)
L185:
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  ret
  nopl   0x0(%rax)
L9:
  movsbl 0x1(%rdx),%esi
  lea    0x2(%rdx),%rcx
  movslq %ebx,%r9
  test   %eax,%eax
  jne    L301
  mov    $0x1,%eax
L157:
  cmp    $0x30,%esi
  je     L133
  test   %ebx,%ebx
  jne    L243
  mov    $0xa,%r9d
  mov    $0xa,%ebx
L51:
  test   %eax,%eax
  je     L193
L301:
  mov    D54(%rip),%rax
  mov    (%rax),%r10
  mov    %r10,%rax
  cqto
  idiv   %r9
  mov    %edx,%r11d
  mov    %rax,%rdi
  test   %rdx,%rdx
  jle    L262
  sub    %ebx,%r11d
  add    $0x1,%rdi
L262:
  mov    D4(%rip),%rax
  neg    %r11d
  xor    %r8d,%r8d
  mov    (%rax),%r13d
  xor    %eax,%eax
  jmp    L106
  nopl   0x0(%rax,%rax,1)
L28:
  cmp    $0xffffffff,%r8d
  je     L348
  cmp    %rdi,%rax
  jl     L292
  jne    L88
  cmp    %r11d,%edx
  jle    L88
L292:
  mov    D38(%rip),%rax
  mov    $0xffffffff,%r8d
  mov    %r13d,(%rax)
  mov    %r10,%rax
L348:
  movzbl (%rcx),%esi
  add    $0x1,%rcx
L106:
  lea    -0x30(%rsi),%edx
  cmp    $0x9,%edx
  jbe    L331
  mov    %esi,%edx
  lea    -0x41(%rsi),%r14d
  and    $0xffffffdf,%edx
  sub    $0x41,%edx
  cmp    $0x19,%edx
  ja     L174
  cmp    $0x1a,%r14d
  sbb    %r14d,%r14d
  and    $0xffffffe0,%r14d
  add    $0x57,%r14d
  sub    %r14d,%esi
  mov    %esi,%edx
L331:
  cmp    %ebx,%edx
  jl     L28
  jmp    L174
  xchg   %ax,%ax
L326:
  imul   %r9,%rax
  movslq %edi,%rdi
  mov    $0x1,%r8d
  add    %rdi,%rax
  jmp    L134
  nopl   (%rax)
L237:
  movsbl 0x1(%rdx),%esi
  lea    0x2(%rdx),%rcx
  movslq %ebx,%r9
  test   %eax,%eax
  jne    L193
  jmp    L157
L88:
  imul   %r9,%rax
  movslq %edx,%rdx
  mov    $0x1,%r8d
  sub    %rdx,%rax
  jmp    L348
L133:
  movzbl (%rcx),%edx
  and    $0xffffffdf,%edx
  cmp    $0x58,%dl
  jne    L42
  movsbl 0x1(%rcx),%esi
  mov    $0x10,%r9d
  add    $0x2,%rcx
  mov    $0x10,%ebx
  jmp    L51
L42:
  test   %ebx,%ebx
  jne    L243
  mov    $0x8,%r9d
  mov    $0x8,%ebx
  jmp    L51
L243:
  movslq %ebx,%r9
  jmp    L51
```

assistant: ```c
long int strtol(const char *nptr, char **endptr, int base) {
  const char *s;
  long acc, cutoff;
  int c;
  int neg, any, cutlim;
  assert(nptr != NULL);
  s = nptr;
  do {
    c = (unsigned char)*s++;
  } while (((c == ' ') || (c == '\n') || (c == '\t')));
  if (c == '-') {
    neg = 1;
    c = *s++;
  } else {
    neg = 0;
    if (c == '+')
      c = *s++;
  }
  if ((base == 0 || base == 16) && c == '0' && (*s == 'x' || *s == 'X')) {
    c = s[1];
    s += 2;
    base = 16;
  }
  if (base == 0)
    base = c == '0' ? 8 : 10;
  cutoff = neg ? LONG_MIN : LONG_MAX;
  cutlim = (int)(cutoff % base);
  cutoff /= base;
  if (neg) {
    if (cutlim > 0) {
      cutlim -= base;
      cutoff += 1;
    }
    cutlim = -cutlim;
  }
  for (acc = 0, any = 0;; c = (unsigned char)*s++) {
    if ((c >= '0' && c <= '9'))
      c -= '0';
    else if ((((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'))))
      c -= ((c >= 'A') && (c <= 'Z')) ? 'A' - 10 : 'a' - 10;
    else
      break;
    if (c >= base)
      break;
    if (any < 0)
      continue;
    if (neg) {
      if (acc < cutoff || (acc == cutoff && c > cutlim)) {
        any = -1;
        acc = LONG_MIN;
        errno = ERANGE;
      } else {
        any = 1;
        acc *= base;
        acc -= c;
      }
    } else {
      if (acc > cutoff || (acc == cutoff && c > cutlim)) {
        any = -1;
        acc = LONG_MAX;
        errno = ERANGE;
      } else {
        any = 1;
        acc *= base;
        acc += c;
      }
    }
  }
  if (endptr != 0)
    *endptr = (char *)(any ? s - 1 : nptr);
  return (acc);
}
```