C++ (Cpp) Inst::orderedOps示例

bool Inst::operator<(const Inst &Other) const {
  if (this == &Other)
    return false;

  if (K < Other.K)
    return true;
  if (K > Other.K)
    return false;

  if (Width < Other.Width)
    return true;
  if (Width > Other.Width)
    return false;

  switch (K) {
  case Const:
    return Val.ult(Other.Val);
  case UntypedConst: {
    llvm::APInt Val1 = Val, Val2 = Other.Val;
    if (Val1.getBitWidth() < Val2.getBitWidth())
      Val1 = Val1.sext(Val2.getBitWidth());
    else if (Val1.getBitWidth() > Val2.getBitWidth())
      Val2 = Val2.sext(Val1.getBitWidth());
    return Val1.slt(Val2);
  }
  case Var:
    return Number < Other.Number;
  case Phi:
    if (B->Number < Other.B->Number)
      return true;
    if (B->Number > Other.B->Number)
      return false;
  default:
    break;
  }

  if (Ops.size() < Other.Ops.size())
    return true;
  if (Ops.size() > Other.Ops.size())
    return false;

  const std::vector<Inst *> &OpsA = orderedOps();
  const std::vector<Inst *> &OpsB = Other.orderedOps();

  for (unsigned I = 0; I != OpsA.size(); ++I) {
    if (OpsA[I] == OpsB[I])
      continue;
    return (*OpsA[I] < *OpsB[I]);
  }

  llvm_unreachable("Should have found an unequal operand");
}