message: swith to LLVM's opaque ptr syntax
diff: @@ -596,7 +596,8 @@ void FloatType::print(ostream &os) const {
  PtrType::PtrType(unsigned addr_space)
  - : Type(addr_space == 0 ? "*" : "as(" + to_string(addr_space) + ")*"),
  + : Type(addr_space == 0 ? "ptr"
  + : "ptr addrspace(" + to_string(addr_space) + ')'),
  addr_space(addr_space), defined(true) {}
  expr PtrType::ASVar() const {
  @@ -687,10 +688,9 @@ void PtrType::printVal(ostream &os, const State &s, const expr &e) const {
  }
  void PtrType::print(ostream &os) const {
  + os << "ptr";
  if (addr_space != 0)
  - os << "as(" << addr_space << ")*";
  - else
  - os << '*';
  + os << " addrspace(" << addr_space << ')';
  }
  