hotspot/src/share/vm/code/codeBlob.hpp - platform/libcore - Git at Google

 /*
  * Copyright 1998-2007 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * 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.
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */

 // CodeBlob - superclass for all entries in the CodeCache.
 //
 // Suptypes are:
 //   nmethod            : Compiled Java methods (include method that calls to native code)
 //   RuntimeStub        : Call to VM runtime methods
 //   DeoptimizationBlob : Used for deoptimizatation
 //   ExceptionBlob      : Used for stack unrolling
 //   SafepointBlob      : Used to handle illegal instruction exceptions
 //
 //
 // Layout:
 //   - header
 //   - relocation
 //   - instruction space
 //   - data space
 class DeoptimizationBlob;

 class CodeBlob VALUE_OBJ_CLASS_SPEC {

   friend class VMStructs;

  private:
   const char* _name;
   int        _size;                              // total size of CodeBlob in bytes
   int        _header_size;                       // size of header (depends on subclass)
   int        _relocation_size;                   // size of relocation
   int        _instructions_offset;               // offset to where instructions region begins
   int        _frame_complete_offset;             // instruction offsets in [0.._frame_complete_offset) have
                                                  // not finished setting up their frame. Beware of pc's in
                                                  // that range. There is a similar range(s) on returns
                                                  // which we don't detect.
   int        _data_offset;                       // offset to where data region begins
   int        _oops_offset;                       // offset to where embedded oop table begins (inside data)
   int        _oops_length;                       // number of embedded oops
   int        _frame_size;                        // size of stack frame
   OopMapSet* _oop_maps;                          // OopMap for this CodeBlob
   CodeComments _comments;

   friend class OopRecorder;

   void fix_oop_relocations(address begin, address end, bool initialize_immediates);
   inline void initialize_immediate_oop(oop* dest, jobject handle);

  public:
   // Returns the space needed for CodeBlob
   static unsigned int allocation_size(CodeBuffer* cb, int header_size);

   // Creation
   // a) simple CodeBlob
   // frame_complete is the offset from the beginning of the instructions
   // to where the frame setup (from stackwalk viewpoint) is complete.
   CodeBlob(const char* name, int header_size, int size, int frame_complete, int locs_size);

   // b) full CodeBlob
   CodeBlob(
     const char* name,
     CodeBuffer* cb,
     int         header_size,
     int         size,
     int         frame_complete,
     int         frame_size,
     OopMapSet*  oop_maps
   );

   // Deletion
   void flush();

   // Typing
   virtual bool is_buffer_blob() const            { return false; }
   virtual bool is_nmethod() const                { return false; }
   virtual bool is_runtime_stub() const           { return false; }
   virtual bool is_deoptimization_stub() const    { return false; }
   virtual bool is_uncommon_trap_stub() const     { return false; }
   virtual bool is_exception_stub() const         { return false; }
   virtual bool is_safepoint_stub() const         { return false; }
   virtual bool is_adapter_blob() const           { return false; }

   virtual bool is_compiled_by_c2() const         { return false; }
   virtual bool is_compiled_by_c1() const         { return false; }

   // Boundaries
   address    header_begin() const                { return (address)    this; }
   address    header_end() const                  { return ((address)   this) + _header_size; };
   relocInfo* relocation_begin() const            { return (relocInfo*) header_end(); };
   relocInfo* relocation_end() const              { return (relocInfo*)(header_end()   + _relocation_size); }
   address    instructions_begin() const          { return (address)    header_begin() + _instructions_offset;  }
   address    instructions_end() const            { return (address)    header_begin() + _data_offset; }
   address    data_begin() const                  { return (address)    header_begin() + _data_offset; }
   address    data_end() const                    { return (address)    header_begin() + _size; }
   oop*       oops_begin() const                  { return (oop*)      (header_begin() + _oops_offset); }
   oop*       oops_end() const                    { return                oops_begin() + _oops_length; }

   // Offsets
   int relocation_offset() const                  { return _header_size; }
   int instructions_offset() const                { return _instructions_offset; }
   int data_offset() const                        { return _data_offset; }
   int oops_offset() const                        { return _oops_offset; }

   // Sizes
   int size() const                               { return _size; }
   int header_size() const                        { return _header_size; }
   int relocation_size() const                    { return (address) relocation_end() - (address) relocation_begin(); }
   int instructions_size() const                  { return instructions_end() - instructions_begin();  }
   int data_size() const                          { return data_end() - data_begin(); }
   int oops_size() const                          { return (address) oops_end() - (address) oops_begin(); }

   // Containment
   bool blob_contains(address addr) const         { return header_begin()       <= addr && addr < data_end(); }
   bool relocation_contains(relocInfo* addr) const{ return relocation_begin()   <= addr && addr < relocation_end(); }
   bool instructions_contains(address addr) const { return instructions_begin() <= addr && addr < instructions_end(); }
   bool data_contains(address addr) const         { return data_begin()         <= addr && addr < data_end(); }
   bool oops_contains(oop* addr) const            { return oops_begin()         <= addr && addr < oops_end(); }
   bool contains(address addr) const              { return instructions_contains(addr); }
   bool is_frame_complete_at(address addr) const  { return instructions_contains(addr) &&
                                                           addr >= instructions_begin() + _frame_complete_offset; }

   // Relocation support
   void fix_oop_relocations(address begin, address end) {
     fix_oop_relocations(begin, end, false);
   }
   void fix_oop_relocations() {
     fix_oop_relocations(NULL, NULL, false);
   }
   relocInfo::relocType reloc_type_for_address(address pc);
   bool is_at_poll_return(address pc);
   bool is_at_poll_or_poll_return(address pc);

   // Support for oops in scopes and relocs:
   // Note: index 0 is reserved for null.
   oop  oop_at(int index) const                   { return index == 0? (oop)NULL: *oop_addr_at(index); }
   oop* oop_addr_at(int index) const{             // for GC
     // relocation indexes are biased by 1 (because 0 is reserved)
     assert(index > 0 && index <= _oops_length, "must be a valid non-zero index");
     return &oops_begin()[index-1];
   }

   void copy_oops(GrowableArray<jobject>* oops);

   // CodeCache support: really only used by the nmethods, but in order to get
   // asserts and certain bookkeeping to work in the CodeCache they are defined
   // virtual here.
   virtual bool is_zombie() const                 { return false; }
   virtual bool is_locked_by_vm() const           { return false; }

   virtual bool is_unloaded() const               { return false; }
   virtual bool is_not_entrant() const            { return false; }

   // GC support
   virtual bool is_alive() const                  = 0;
   virtual void do_unloading(BoolObjectClosure* is_alive,
                             OopClosure* keep_alive,
                             bool unloading_occurred);
   virtual void oops_do(OopClosure* f) = 0;

   // OopMap for frame
   OopMapSet* oop_maps() const                    { return _oop_maps; }
   void set_oop_maps(OopMapSet* p);
   OopMap* oop_map_for_return_address(address return_address);
   virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { ShouldNotReachHere(); }

   // Frame support
   int  frame_size() const                        { return _frame_size; }
   void set_frame_size(int size)                  { _frame_size = size; }

   // Returns true, if the next frame is responsible for GC'ing oops passed as arguments
   virtual bool caller_must_gc_arguments(JavaThread* thread) const { return false; }

   // Naming
   const char* name() const                       { return _name; }
   void set_name(const char* name)                { _name = name; }

   // Debugging
   virtual void verify();
   virtual void print() const                     PRODUCT_RETURN;
   virtual void print_value_on(outputStream* st) const PRODUCT_RETURN;

   // Print the comment associated with offset on stream, if there is one
   void print_block_comment(outputStream* stream, intptr_t offset) {
     _comments.print_block_comment(stream, offset);
   }

   // Transfer ownership of comments to this CodeBlob
   void set_comments(CodeComments& comments) {
     _comments.assign(comments);
   }
 };


 //----------------------------------------------------------------------------------------------------
 // BufferBlob: used to hold non-relocatable machine code such as the interpreter, stubroutines, etc.

 class BufferBlob: public CodeBlob {
   friend class VMStructs;
  private:
   // Creation support
   BufferBlob(const char* name, int size);
   BufferBlob(const char* name, int size, CodeBuffer* cb);

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static BufferBlob* create(const char* name, int buffer_size);
   static BufferBlob* create(const char* name, CodeBuffer* cb);

   static void free(BufferBlob* buf);

   // Typing
   bool is_buffer_blob() const                    { return true; }
   bool is_adapter_blob() const;

   // GC/Verification support
   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
   bool is_alive() const                          { return true; }
   void do_unloading(BoolObjectClosure* is_alive,
                     OopClosure* keep_alive,
                     bool unloading_occurred)     { /* do nothing */ }

   void oops_do(OopClosure* f)                    { /* do nothing*/ }

   void verify();
   void print() const                             PRODUCT_RETURN;
   void print_value_on(outputStream* st) const    PRODUCT_RETURN;
 };


 //----------------------------------------------------------------------------------------------------
 // RuntimeStub: describes stubs used by compiled code to call a (static) C++ runtime routine

 class RuntimeStub: public CodeBlob {
   friend class VMStructs;
  private:
   bool        _caller_must_gc_arguments;

   // Creation support
   RuntimeStub(
     const char* name,
     CodeBuffer* cb,
     int         size,
     int         frame_complete,
     int         frame_size,
     OopMapSet*  oop_maps,
     bool        caller_must_gc_arguments
   );

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static RuntimeStub* new_runtime_stub(
     const char* stub_name,
     CodeBuffer* cb,
     int         frame_complete,
     int         frame_size,
     OopMapSet*  oop_maps,
     bool        caller_must_gc_arguments
   );

   // Typing
   bool is_runtime_stub() const                   { return true; }

   // GC support
   bool caller_must_gc_arguments(JavaThread* thread) const { return _caller_must_gc_arguments; }

   address entry_point()                          { return instructions_begin(); }

   // GC/Verification support
   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
   bool is_alive() const                          { return true; }
   void do_unloading(BoolObjectClosure* is_alive,
                     OopClosure* keep_alive,
                     bool unloading_occurred)     { /* do nothing */ }
   void oops_do(OopClosure* f) { /* do-nothing*/ }

   void verify();
   void print() const                             PRODUCT_RETURN;
   void print_value_on(outputStream* st) const    PRODUCT_RETURN;
 };


 //----------------------------------------------------------------------------------------------------
 // Super-class for all blobs that exist in only one instance. Implements default behaviour.

 class SingletonBlob: public CodeBlob {
   friend class VMStructs;
   public:
    SingletonBlob(
      const char* name,
      CodeBuffer* cb,
      int         header_size,
      int         size,
      int         frame_size,
      OopMapSet*  oop_maps
    )
    : CodeBlob(name, cb, header_size, size, CodeOffsets::frame_never_safe, frame_size, oop_maps)
    {};

    bool is_alive() const                         { return true; }
    void do_unloading(BoolObjectClosure* is_alive,
                      OopClosure* keep_alive,
                      bool unloading_occurred)    { /* do-nothing*/ }

    void verify(); // does nothing
    void print() const                            PRODUCT_RETURN;
    void print_value_on(outputStream* st) const   PRODUCT_RETURN;
 };


 //----------------------------------------------------------------------------------------------------
 // DeoptimizationBlob

 class DeoptimizationBlob: public SingletonBlob {
   friend class VMStructs;
  private:
   int _unpack_offset;
   int _unpack_with_exception;
   int _unpack_with_reexecution;

   int _unpack_with_exception_in_tls;

   // Creation support
   DeoptimizationBlob(
     CodeBuffer* cb,
     int         size,
     OopMapSet*  oop_maps,
     int         unpack_offset,
     int         unpack_with_exception_offset,
     int         unpack_with_reexecution_offset,
     int         frame_size
   );

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static DeoptimizationBlob* create(
     CodeBuffer* cb,
     OopMapSet*  oop_maps,
     int         unpack_offset,
     int         unpack_with_exception_offset,
     int         unpack_with_reexecution_offset,
     int         frame_size
   );

   // Typing
   bool is_deoptimization_stub() const { return true; }
   const DeoptimizationBlob *as_deoptimization_stub() const { return this; }
   bool exception_address_is_unpack_entry(address pc) const {
     address unpack_pc = unpack();
     return (pc == unpack_pc || (pc + frame::pc_return_offset) == unpack_pc);
   }


   // GC for args
   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { /* Nothing to do */ }

   // Iteration
   void oops_do(OopClosure* f) {}

   // Printing
   void print_value_on(outputStream* st) const PRODUCT_RETURN;

   address unpack() const                         { return instructions_begin() + _unpack_offset;           }
   address unpack_with_exception() const          { return instructions_begin() + _unpack_with_exception;   }
   address unpack_with_reexecution() const        { return instructions_begin() + _unpack_with_reexecution; }

   // Alternate entry point for C1 where the exception and issuing pc
   // are in JavaThread::_exception_oop and JavaThread::_exception_pc
   // instead of being in registers.  This is needed because C1 doesn't
   // model exception paths in a way that keeps these registers free so
   // there may be live values in those registers during deopt.
   void set_unpack_with_exception_in_tls_offset(int offset) {
     _unpack_with_exception_in_tls = offset;
     assert(contains(instructions_begin() + _unpack_with_exception_in_tls), "must be PC inside codeblob");
   }
   address unpack_with_exception_in_tls() const   { return instructions_begin() + _unpack_with_exception_in_tls;   }
 };


 //----------------------------------------------------------------------------------------------------
 // UncommonTrapBlob (currently only used by Compiler 2)

 #ifdef COMPILER2

 class UncommonTrapBlob: public SingletonBlob {
   friend class VMStructs;
  private:
   // Creation support
   UncommonTrapBlob(
     CodeBuffer* cb,
     int         size,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static UncommonTrapBlob* create(
     CodeBuffer* cb,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   // GC for args
   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }

   // Typing
   bool is_uncommon_trap_stub() const             { return true; }

   // Iteration
   void oops_do(OopClosure* f) {}
 };


 //----------------------------------------------------------------------------------------------------
 // ExceptionBlob: used for exception unwinding in compiled code (currently only used by Compiler 2)

 class ExceptionBlob: public SingletonBlob {
   friend class VMStructs;
  private:
   // Creation support
   ExceptionBlob(
     CodeBuffer* cb,
     int         size,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static ExceptionBlob* create(
     CodeBuffer* cb,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   // GC for args
   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }

   // Typing
   bool is_exception_stub() const                 { return true; }

   // Iteration
   void oops_do(OopClosure* f) {}
 };
 #endif // COMPILER2


 //----------------------------------------------------------------------------------------------------
 // SafepointBlob: handles illegal_instruction exceptions during a safepoint

 class SafepointBlob: public SingletonBlob {
   friend class VMStructs;
  private:
   // Creation support
   SafepointBlob(
     CodeBuffer* cb,
     int         size,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   void* operator new(size_t s, unsigned size);

  public:
   // Creation
   static SafepointBlob* create(
     CodeBuffer* cb,
     OopMapSet*  oop_maps,
     int         frame_size
   );

   // GC for args
   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }

   // Typing
   bool is_safepoint_stub() const                 { return true; }

   // Iteration
   void oops_do(OopClosure* f) {}
 };
	/*
	* Copyright 1998-2007 Sun Microsystems, Inc. All Rights Reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* 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.
	*
	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
	* CA 95054 USA or visit www.sun.com if you need additional information or
	* have any questions.
	*
	*/

	// CodeBlob - superclass for all entries in the CodeCache.
	//
	// Suptypes are:
	// nmethod : Compiled Java methods (include method that calls to native code)
	// RuntimeStub : Call to VM runtime methods
	// DeoptimizationBlob : Used for deoptimizatation
	// ExceptionBlob : Used for stack unrolling
	// SafepointBlob : Used to handle illegal instruction exceptions
	//
	//
	// Layout:
	// - header
	// - relocation
	// - instruction space
	// - data space
	class DeoptimizationBlob;

	class CodeBlob VALUE_OBJ_CLASS_SPEC {

	friend class VMStructs;

	private:
	const char* _name;
	int _size; // total size of CodeBlob in bytes
	int _header_size; // size of header (depends on subclass)
	int _relocation_size; // size of relocation
	int _instructions_offset; // offset to where instructions region begins
	int _frame_complete_offset; // instruction offsets in [0.._frame_complete_offset) have
	// not finished setting up their frame. Beware of pc's in
	// that range. There is a similar range(s) on returns
	// which we don't detect.
	int _data_offset; // offset to where data region begins
	int _oops_offset; // offset to where embedded oop table begins (inside data)
	int _oops_length; // number of embedded oops
	int _frame_size; // size of stack frame
	OopMapSet* _oop_maps; // OopMap for this CodeBlob
	CodeComments _comments;

	friend class OopRecorder;

	void fix_oop_relocations(address begin, address end, bool initialize_immediates);
	inline void initialize_immediate_oop(oop* dest, jobject handle);

	public:
	// Returns the space needed for CodeBlob
	static unsigned int allocation_size(CodeBuffer* cb, int header_size);

	// Creation
	// a) simple CodeBlob
	// frame_complete is the offset from the beginning of the instructions
	// to where the frame setup (from stackwalk viewpoint) is complete.
	CodeBlob(const char* name, int header_size, int size, int frame_complete, int locs_size);

	// b) full CodeBlob
	CodeBlob(
	const char* name,
	CodeBuffer* cb,
	int header_size,
	int size,
	int frame_complete,
	int frame_size,
	OopMapSet* oop_maps
	);

	// Deletion
	void flush();

	// Typing
	virtual bool is_buffer_blob() const { return false; }
	virtual bool is_nmethod() const { return false; }
	virtual bool is_runtime_stub() const { return false; }
	virtual bool is_deoptimization_stub() const { return false; }
	virtual bool is_uncommon_trap_stub() const { return false; }
	virtual bool is_exception_stub() const { return false; }
	virtual bool is_safepoint_stub() const { return false; }
	virtual bool is_adapter_blob() const { return false; }

	virtual bool is_compiled_by_c2() const { return false; }
	virtual bool is_compiled_by_c1() const { return false; }

	// Boundaries
	address header_begin() const { return (address) this; }
	address header_end() const { return ((address) this) + _header_size; };
	relocInfo* relocation_begin() const { return (relocInfo*) header_end(); };
	relocInfo* relocation_end() const { return (relocInfo*)(header_end() + _relocation_size); }
	address instructions_begin() const { return (address) header_begin() + _instructions_offset; }
	address instructions_end() const { return (address) header_begin() + _data_offset; }
	address data_begin() const { return (address) header_begin() + _data_offset; }
	address data_end() const { return (address) header_begin() + _size; }
	oop* oops_begin() const { return (oop*) (header_begin() + _oops_offset); }
	oop* oops_end() const { return oops_begin() + _oops_length; }

	// Offsets
	int relocation_offset() const { return _header_size; }
	int instructions_offset() const { return _instructions_offset; }
	int data_offset() const { return _data_offset; }
	int oops_offset() const { return _oops_offset; }

	// Sizes
	int size() const { return _size; }
	int header_size() const { return _header_size; }
	int relocation_size() const { return (address) relocation_end() - (address) relocation_begin(); }
	int instructions_size() const { return instructions_end() - instructions_begin(); }
	int data_size() const { return data_end() - data_begin(); }
	int oops_size() const { return (address) oops_end() - (address) oops_begin(); }

	// Containment
	bool blob_contains(address addr) const { return header_begin() <= addr && addr < data_end(); }
	bool relocation_contains(relocInfo* addr) const{ return relocation_begin() <= addr && addr < relocation_end(); }
	bool instructions_contains(address addr) const { return instructions_begin() <= addr && addr < instructions_end(); }
	bool data_contains(address addr) const { return data_begin() <= addr && addr < data_end(); }
	bool oops_contains(oop* addr) const { return oops_begin() <= addr && addr < oops_end(); }
	bool contains(address addr) const { return instructions_contains(addr); }
	bool is_frame_complete_at(address addr) const { return instructions_contains(addr) &&
	addr >= instructions_begin() + _frame_complete_offset; }

	// Relocation support
	void fix_oop_relocations(address begin, address end) {
	fix_oop_relocations(begin, end, false);
	}
	void fix_oop_relocations() {
	fix_oop_relocations(NULL, NULL, false);
	}
	relocInfo::relocType reloc_type_for_address(address pc);
	bool is_at_poll_return(address pc);
	bool is_at_poll_or_poll_return(address pc);

	// Support for oops in scopes and relocs:
	// Note: index 0 is reserved for null.
	oop oop_at(int index) const { return index == 0? (oop)NULL: *oop_addr_at(index); }
	oop* oop_addr_at(int index) const{ // for GC
	// relocation indexes are biased by 1 (because 0 is reserved)
	assert(index > 0 && index <= _oops_length, "must be a valid non-zero index");
	return &oops_begin()[index-1];
	}

	void copy_oops(GrowableArray<jobject>* oops);

	// CodeCache support: really only used by the nmethods, but in order to get
	// asserts and certain bookkeeping to work in the CodeCache they are defined
	// virtual here.
	virtual bool is_zombie() const { return false; }
	virtual bool is_locked_by_vm() const { return false; }

	virtual bool is_unloaded() const { return false; }
	virtual bool is_not_entrant() const { return false; }

	// GC support
	virtual bool is_alive() const = 0;
	virtual void do_unloading(BoolObjectClosure* is_alive,
	OopClosure* keep_alive,
	bool unloading_occurred);
	virtual void oops_do(OopClosure* f) = 0;

	// OopMap for frame
	OopMapSet* oop_maps() const { return _oop_maps; }
	void set_oop_maps(OopMapSet* p);
	OopMap* oop_map_for_return_address(address return_address);
	virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) { ShouldNotReachHere(); }

	// Frame support
	int frame_size() const { return _frame_size; }
	void set_frame_size(int size) { _frame_size = size; }

	// Returns true, if the next frame is responsible for GC'ing oops passed as arguments
	virtual bool caller_must_gc_arguments(JavaThread* thread) const { return false; }

	// Naming
	const char* name() const { return _name; }
	void set_name(const char* name) { _name = name; }

	// Debugging
	virtual void verify();
	virtual void print() const PRODUCT_RETURN;
	virtual void print_value_on(outputStream* st) const PRODUCT_RETURN;

	// Print the comment associated with offset on stream, if there is one
	void print_block_comment(outputStream* stream, intptr_t offset) {
	_comments.print_block_comment(stream, offset);
	}

	// Transfer ownership of comments to this CodeBlob
	void set_comments(CodeComments& comments) {
	_comments.assign(comments);
	}
	};


	//----------------------------------------------------------------------------------------------------
	// BufferBlob: used to hold non-relocatable machine code such as the interpreter, stubroutines, etc.

	class BufferBlob: public CodeBlob {
	friend class VMStructs;
	private:
	// Creation support
	BufferBlob(const char* name, int size);
	BufferBlob(const char* name, int size, CodeBuffer* cb);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static BufferBlob* create(const char* name, int buffer_size);
	static BufferBlob* create(const char* name, CodeBuffer* cb);

	static void free(BufferBlob* buf);

	// Typing
	bool is_buffer_blob() const { return true; }
	bool is_adapter_blob() const;

	// GC/Verification support
	void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) { /* nothing to do */ }
	bool is_alive() const { return true; }
	void do_unloading(BoolObjectClosure* is_alive,
	OopClosure* keep_alive,
	bool unloading_occurred) { /* do nothing */ }

	void oops_do(OopClosure* f) { /* do nothing*/ }

	void verify();
	void print() const PRODUCT_RETURN;
	void print_value_on(outputStream* st) const PRODUCT_RETURN;
	};


	//----------------------------------------------------------------------------------------------------
	// RuntimeStub: describes stubs used by compiled code to call a (static) C++ runtime routine

	class RuntimeStub: public CodeBlob {
	friend class VMStructs;
	private:
	bool _caller_must_gc_arguments;

	// Creation support
	RuntimeStub(
	const char* name,
	CodeBuffer* cb,
	int size,
	int frame_complete,
	int frame_size,
	OopMapSet* oop_maps,
	bool caller_must_gc_arguments
	);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static RuntimeStub* new_runtime_stub(
	const char* stub_name,
	CodeBuffer* cb,
	int frame_complete,
	int frame_size,
	OopMapSet* oop_maps,
	bool caller_must_gc_arguments
	);

	// Typing
	bool is_runtime_stub() const { return true; }

	// GC support
	bool caller_must_gc_arguments(JavaThread* thread) const { return _caller_must_gc_arguments; }

	address entry_point() { return instructions_begin(); }

	// GC/Verification support
	void preserve_callee_argument_oops(frame fr, const RegisterMap reg_map, OopClosure f) { /* nothing to do */ }
	bool is_alive() const { return true; }
	void do_unloading(BoolObjectClosure* is_alive,
	OopClosure* keep_alive,
	bool unloading_occurred) { /* do nothing */ }
	void oops_do(OopClosure* f) { /* do-nothing*/ }

	void verify();
	void print() const PRODUCT_RETURN;
	void print_value_on(outputStream* st) const PRODUCT_RETURN;
	};


	//----------------------------------------------------------------------------------------------------
	// Super-class for all blobs that exist in only one instance. Implements default behaviour.

	class SingletonBlob: public CodeBlob {
	friend class VMStructs;
	public:
	SingletonBlob(
	const char* name,
	CodeBuffer* cb,
	int header_size,
	int size,
	int frame_size,
	OopMapSet* oop_maps
	)
	: CodeBlob(name, cb, header_size, size, CodeOffsets::frame_never_safe, frame_size, oop_maps)
	{};

	bool is_alive() const { return true; }
	void do_unloading(BoolObjectClosure* is_alive,
	OopClosure* keep_alive,
	bool unloading_occurred) { /* do-nothing*/ }

	void verify(); // does nothing
	void print() const PRODUCT_RETURN;
	void print_value_on(outputStream* st) const PRODUCT_RETURN;
	};


	//----------------------------------------------------------------------------------------------------
	// DeoptimizationBlob

	class DeoptimizationBlob: public SingletonBlob {
	friend class VMStructs;
	private:
	int _unpack_offset;
	int _unpack_with_exception;
	int _unpack_with_reexecution;

	int _unpack_with_exception_in_tls;

	// Creation support
	DeoptimizationBlob(
	CodeBuffer* cb,
	int size,
	OopMapSet* oop_maps,
	int unpack_offset,
	int unpack_with_exception_offset,
	int unpack_with_reexecution_offset,
	int frame_size
	);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static DeoptimizationBlob* create(
	CodeBuffer* cb,
	OopMapSet* oop_maps,
	int unpack_offset,
	int unpack_with_exception_offset,
	int unpack_with_reexecution_offset,
	int frame_size
	);

	// Typing
	bool is_deoptimization_stub() const { return true; }
	const DeoptimizationBlob *as_deoptimization_stub() const { return this; }
	bool exception_address_is_unpack_entry(address pc) const {
	address unpack_pc = unpack();
	return (pc == unpack_pc \|\| (pc + frame::pc_return_offset) == unpack_pc);
	}




	// GC for args
	void preserve_callee_argument_oops(frame fr, const RegisterMap reg_map, OopClosure f) { /* Nothing to do */ }

	// Iteration
	void oops_do(OopClosure* f) {}

	// Printing
	void print_value_on(outputStream* st) const PRODUCT_RETURN;

	address unpack() const { return instructions_begin() + _unpack_offset; }
	address unpack_with_exception() const { return instructions_begin() + _unpack_with_exception; }
	address unpack_with_reexecution() const { return instructions_begin() + _unpack_with_reexecution; }

	// Alternate entry point for C1 where the exception and issuing pc
	// are in JavaThread::_exception_oop and JavaThread::_exception_pc
	// instead of being in registers. This is needed because C1 doesn't
	// model exception paths in a way that keeps these registers free so
	// there may be live values in those registers during deopt.
	void set_unpack_with_exception_in_tls_offset(int offset) {
	_unpack_with_exception_in_tls = offset;
	assert(contains(instructions_begin() + _unpack_with_exception_in_tls), "must be PC inside codeblob");
	}
	address unpack_with_exception_in_tls() const { return instructions_begin() + _unpack_with_exception_in_tls; }
	};


	//----------------------------------------------------------------------------------------------------
	// UncommonTrapBlob (currently only used by Compiler 2)

	#ifdef COMPILER2

	class UncommonTrapBlob: public SingletonBlob {
	friend class VMStructs;
	private:
	// Creation support
	UncommonTrapBlob(
	CodeBuffer* cb,
	int size,
	OopMapSet* oop_maps,
	int frame_size
	);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static UncommonTrapBlob* create(
	CodeBuffer* cb,
	OopMapSet* oop_maps,
	int frame_size
	);

	// GC for args
	void preserve_callee_argument_oops(frame fr, const RegisterMap reg_map, OopClosure f) { /* nothing to do */ }

	// Typing
	bool is_uncommon_trap_stub() const { return true; }

	// Iteration
	void oops_do(OopClosure* f) {}
	};


	//----------------------------------------------------------------------------------------------------
	// ExceptionBlob: used for exception unwinding in compiled code (currently only used by Compiler 2)

	class ExceptionBlob: public SingletonBlob {
	friend class VMStructs;
	private:
	// Creation support
	ExceptionBlob(
	CodeBuffer* cb,
	int size,
	OopMapSet* oop_maps,
	int frame_size
	);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static ExceptionBlob* create(
	CodeBuffer* cb,
	OopMapSet* oop_maps,
	int frame_size
	);

	// GC for args
	void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) { /* nothing to do */ }

	// Typing
	bool is_exception_stub() const { return true; }

	// Iteration
	void oops_do(OopClosure* f) {}
	};
	#endif // COMPILER2


	//----------------------------------------------------------------------------------------------------
	// SafepointBlob: handles illegal_instruction exceptions during a safepoint

	class SafepointBlob: public SingletonBlob {
	friend class VMStructs;
	private:
	// Creation support
	SafepointBlob(
	CodeBuffer* cb,
	int size,
	OopMapSet* oop_maps,
	int frame_size
	);

	void* operator new(size_t s, unsigned size);

	public:
	// Creation
	static SafepointBlob* create(
	CodeBuffer* cb,
	OopMapSet* oop_maps,
	int frame_size
	);

	// GC for args
	void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f) { /* nothing to do */ }

	// Typing
	bool is_safepoint_stub() const { return true; }

	// Iteration
	void oops_do(OopClosure* f) {}
	};