mkgist-created gist

pseudo.txt

void JSString::traceBase(JSTracer* trc) {
  MOZ_ASSERT(hasBase());
  JSString* oldBase = d.s.u3.base;
  if (I am a DependentString) {
    // Handle the case where I am a dependent string of an undependend string,
    // and therefore my chars are actually coming from its base.
    base = my base
    while (my chars do not come from MaybeForwarded(base).chars) {
      if (base.hasBase)
        base = base.base
      else
        break // I might be a dependent string of an inline string or something
    }
    offset = baseOffset();
  }

  // Update the base from a nursery pointer to a tenured pointer, if necessary.
  TraceManuallyBarrieredEdge(trc, &d.s.u3.base, "base");

  // If I updated the base pointer to a deduplicated string, then
  // re-point my chars to the deduplicated string's chars.
  if (oldBase != d.s.u3.base) {
    char* oldBaseChars = oldBase->chars;
    if (mychars is within oldBaseChars..length)
      repoint to d.s.u3.base's chars
  }
}