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 * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef CPU_ZERO_SMALLREGISTERMAP_ZERO_INLINE_HPP
#define CPU_ZERO_SMALLREGISTERMAP_ZERO_INLINE_HPP

#include "runtime/frame.inline.hpp"
#include "runtime/registerMap.hpp"

// Java frames don't have callee saved registers (except for rfp), so we can use a smaller RegisterMap
class SmallRegisterMap {
  constexpr SmallRegisterMap() = default;
  ~SmallRegisterMap() = default;
  NONCOPYABLE(SmallRegisterMap);

public:
  static const SmallRegisterMap* instance() {
    static constexpr SmallRegisterMap the_instance{};
    return &the_instance;
  }
private:
  static void assert_is_rfp(VMReg r) NOT_DEBUG_RETURN
                                     DEBUG_ONLY({ Unimplemented(); })
public:
  // as_RegisterMap is used when we didn't want to templatize and abstract over RegisterMap type to support SmallRegisterMap
  // Consider enhancing SmallRegisterMap to support those cases
  const RegisterMap* as_RegisterMap() const { return nullptr; }
  RegisterMap* as_RegisterMap() { return nullptr; }

  RegisterMap* copy_to_RegisterMap(RegisterMap* map, intptr_t* sp) const {
    Unimplemented();
    return map;
  }

  inline address location(VMReg reg, intptr_t* sp) const {
    Unimplemented();
    return nullptr;
  }

  inline void set_location(VMReg reg, address loc) { assert_is_rfp(reg); }

  JavaThread* thread() const {
  #ifndef ASSERT
    guarantee (false, "");
  #endif
    return nullptr;
  }

  bool update_map()    const { return false; }
  bool walk_cont()     const { return false; }
  bool include_argument_oops() const { return false; }
  void set_include_argument_oops(bool f)  {}
  bool in_cont()       const { return false; }
  stackChunkHandle stack_chunk() const { return stackChunkHandle(); }

#ifdef ASSERT
  bool should_skip_missing() const  { return false; }
  VMReg find_register_spilled_here(void* p, intptr_t* sp) {
    Unimplemented();
    return nullptr;
  }
  void print() const { print_on(tty); }
  void print_on(outputStream* st) const { st->print_cr("Small register map"); }
#endif
};

#endif // CPU_ZERO_SMALLREGISTERMAP_ZERO_INLINE_HPP