IfConversion.cpp

  for (unsigned i = 0, e = Succs.size(); i != e; ++i) {
    MachineBasicBlock *Succ = Succs[i];
    // Fallthrough edge can't be transferred.
    if (Succ == FallThrough)
      continue;
    FromBBI.BB->removeSuccessor(Succ);
    if (!ToBBI.BB->isSuccessor(Succ))
      ToBBI.BB->addSuccessor(Succ);
  }

  // Now FromBBI always fall through to the next block!
  if (NBB)
    FromBBI.BB->addSuccessor(NBB);

  ToBBI.NonPredSize += FromBBI.NonPredSize;
  FromBBI.NonPredSize = 0;

  ToBBI.ClobbersPred |= FromBBI.ClobbersPred;
  ToBBI.HasFallThrough = FromBBI.HasFallThrough;

  std::copy(FromBBI.Predicate.begin(), FromBBI.Predicate.end(),
            std::back_inserter(ToBBI.Predicate));
  FromBBI.Predicate.clear();

  ToBBI.IsAnalyzed = false;
  FromBBI.IsAnalyzed = false;
}