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cpython PyObject 继承机制的实现

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(lldb) call PyUnicode_FromWideChar(L"算法符合", -1)
(_object *) $16 = 0x000001fd3a9e0a50
(lldb) p *$16
(_object) $17 = {
  ob_refcnt = 1
  ob_type = 0x00007fff35396140
}
(lldb) p *(PyASCIIObject *)$16
(PyASCIIObject) $18 = {
  ob_base = {
    ob_refcnt = 1
    ob_type = 0x00007fff35396140
  }
  length = 4
  hash = -1
  state = (interned = 0, kind = 2, compact = 1, ascii = 0, ready = 1)
  wstr = 0x000001fd3a9e0a98 L"算法符合"
}
(lldb) p *(PyCompactUnicodeObject *)$16
(PyCompactUnicodeObject) $20 = {
  _base = {
    ob_base = {
      ob_refcnt = 1
      ob_type = 0x00007fff35396140
    }
    length = 4
    hash = -1
    state = (interned = 0, kind = 2, compact = 1, ascii = 0, ready = 1)
    wstr = 0x000001fd3a9e0a98 L"算法符合"
  }
  utf8_length = 0
  utf8 = 0x0000000000000000
  wstr_length = 4
}
(lldb) p *(PyUnicodeObject *)$16
(PyUnicodeObject) $19 = {
  _base = {
    _base = {
      ob_base = {
        ob_refcnt = 1
        ob_type = 0x00007fff35396140
      }
      length = 4
      hash = -1
      state = (interned = 0, kind = 2, compact = 1, ascii = 0, ready = 1)
      wstr = 0x000001fd3a9e0a98 L"算法符合"
    }
    utf8_length = 0
    utf8 = 0x0000000000000000
    wstr_length = 4
  }
  data = (interned = 3, kind = 5, compact = 0, ascii = 0, ready = 1)
}

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PyObject * PyUnicode_FromWideChar(const wchar_t *u, Py_ssize_t size)
PyObject * PyUnicode_New(Py_ssize_t size, Py_UCS4 maxchar)
_PyUnicode_CONVERT_BYTES

    struct_size = sizeof(PyCompactUnicodeObject);
    if (maxchar < 128) {
        kind = PyUnicode_1BYTE_KIND;
        char_size = 1;
        is_ascii = 1;
        struct_size = sizeof(PyASCIIObject);
    }
    
        obj = (PyObject *) PyObject_Malloc(struct_size + (size + 1) * char_size);

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(lldb) p *(PyASCIIObject *)unicode
(PyASCIIObject) $18 = {
  ob_base = {
    ob_refcnt = 1
    ob_type = 0x00007fff35396140
  }
  length = 67
  hash = -1
  state = (interned = 0, kind = 1, compact = 1, ascii = 1, ready = 1)
  wstr = 0x0000000000000000
}

					do {
  unsigned char *_to = (unsigned char *)(((
      Py_UCS1
          *)((void)((!!(PyType_HasFeature((((PyObject *)(unicode))->ob_type),
                                          (1UL << 28)))) ||
                    (_wassert(L"PyUnicode_Check(unicode)", L"_file_name_",
                              (unsigned)(2255)),
                     0)),
             (((PyASCIIObject *)(unicode))->state.compact)
                 ? (((void)((!!(PyType_HasFeature(
                                (((PyObject *)(unicode))->ob_type),
                                (1UL << 28)))) ||
                            (_wassert(L"PyUnicode_Check(unicode)",
                                      L"_file_name_", (unsigned)(2255)),
                             0)),
                     (void)((!!((((PyASCIIObject *)unicode)->state.ready))) ||
                            (_wassert(L"PyUnicode_IS_READY(unicode)",
                                      L"_file_name_", (unsigned)(2255)),
                             0)),
                     ((PyASCIIObject *)unicode)->state.ascii)
                        ? ((void *)((PyASCIIObject *)(unicode) + 1))
                        : ((void *)((PyCompactUnicodeObject *)(unicode) + 1)))
                 : ((void)((!!(((PyUnicodeObject *)(unicode))->data.any)) ||
                           (_wassert(L"((PyUnicodeObject*)(unicode))->data.any",
                                     L"_file_name_", (unsigned)(2255)),
                            0)),
                    ((((PyUnicodeObject *)(unicode))->data.any))))));
  const Py_UNICODE *_iter = (const Py_UNICODE *)(u);
  const Py_UNICODE *_end = (const Py_UNICODE *)(u + size);
  Py_ssize_t n = (_end) - (_iter);
  const Py_UNICODE *_unrolled_end = _iter + ((size_t)(n) & ~(size_t)((4) - 1));
  while (_iter < (_unrolled_end)) {
    _to[0] = (unsigned char)_iter[0];
    _to[1] = (unsigned char)_iter[1];
    _to[2] = (unsigned char)_iter[2];
    _to[3] = (unsigned char)_iter[3];
    _iter += 4;
    _to += 4;
  }
  while (_iter < (_end))
    *_to++ = (unsigned char)*_iter++;
} while (0)


(lldb) p ((void *)((PyASCIIObject *)(unicode) + 1))
(void *) $19 = 0x0000021aa88448e0
(lldb) p ((const char *)((PyASCIIObject *)(unicode) + 1))
(const char *) $20 = 0x0000021aa88448e0 "G:\projects\open_source_projects\cpython\PCbuild\amd64\python_d.exe"