/*

 * Copyright (c) 1997, 2005, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#define ARENA_ALIGN_M1 (((size_t)(ARENA_AMALLOC_ALIGNMENT)) - 1)

#define ARENA_ALIGN_MASK (~((size_t)ARENA_ALIGN_M1))

#define ARENA_ALIGN(x) ((((size_t)(x)) + ARENA_ALIGN_M1) & ARENA_ALIGN_MASK)

// All classes in the virtual machine must be subclassed

// by one of the following allocation classes:

//

// For objects allocated in the resource area (see resourceArea.hpp).

// - ResourceObj

//

// For objects allocated in the C-heap (managed by: free & malloc).

// - CHeapObj

//

// For objects allocated on the stack.

// - StackObj

//

// For embedded objects.

// - ValueObj

//

// For classes used as name spaces.

// - AllStatic

//

// The printable subclasses are used for debugging and define virtual

// member functions for printing. Classes that avoid allocating the

// vtbl entries in the objects should therefore not be the printable

// subclasses.

//

// The following macros and function should be used to allocate memory

// directly in the resource area or in the C-heap:

//

//   NEW_RESOURCE_ARRAY(type,size)

//   NEW_RESOURCE_OBJ(type)

//   NEW_C_HEAP_ARRAY(type,size)

//   NEW_C_HEAP_OBJ(type)

//   char* AllocateHeap(size_t size, const char* name);

//   void  FreeHeap(void* p);

//

// C-heap allocation can be traced using +PrintHeapAllocation.

// malloc and free should therefore never called directly.

// Base class for objects allocated in the C-heap.

// In non product mode we introduce a super class for all allocation classes

// that supports printing.

// We avoid the superclass in product mode since some C++ compilers add

// a word overhead for empty super classes.

#ifdef PRODUCT

#define ALLOCATION_SUPER_CLASS_SPEC

#else

#define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj

class AllocatedObj {

 public:

  // Printing support

  void print() const;

  void print_value() const;

  virtual void print_on(outputStream* st) const;

  virtual void print_value_on(outputStream* st) const;

};

#endif

class CHeapObj ALLOCATION_SUPER_CLASS_SPEC {

 public:

  void* operator new(size_t size);

  void  operator delete(void* p);

  void* new_array(size_t size);

};

// Base class for objects allocated on the stack only.

// Calling new or delete will result in fatal error.

class StackObj ALLOCATION_SUPER_CLASS_SPEC {

 public:

  void* operator new(size_t size);

  void  operator delete(void* p);

};

// Base class for objects used as value objects.

// Calling new or delete will result in fatal error.

//

// Portability note: Certain compilers (e.g. gcc) will

// always make classes bigger if it has a superclass, even

// if the superclass does not have any virtual methods or

// instance fields. The HotSpot implementation relies on this

// not to happen. So never make a ValueObj class a direct subclass

// of this object, but use the VALUE_OBJ_CLASS_SPEC class instead, e.g.,

// like this:

//

//   class A VALUE_OBJ_CLASS_SPEC {

//     ...

//   }

//

// With gcc and possible other compilers the VALUE_OBJ_CLASS_SPEC can

// be defined as a an empty string "".

//

class _ValueObj {

 public:

  void* operator new(size_t size);

  void operator delete(void* p);

};

// Base class for classes that constitute name spaces.

class AllStatic {

 public:

  AllStatic()  { ShouldNotCallThis(); }

  ~AllStatic() { ShouldNotCallThis(); }

};

//------------------------------Chunk------------------------------------------

// Linked list of raw memory chunks

class Chunk: public CHeapObj {

 protected:

  Chunk*       _next;     // Next Chunk in list

  const size_t _len;      // Size of this Chunk

 public:

  void* operator new(size_t size, size_t length);

  void  operator delete(void* p);

  Chunk(size_t length);

  enum {

    // default sizes; make them slightly smaller than 2**k to guard against

    // buddy-system style malloc implementations

#ifdef _LP64

    slack      = 40,            // [RGV] Not sure if this is right, but make it

                                //       a multiple of 8.

#else

    slack      = 20,            // suspected sizeof(Chunk) + internal malloc headers

#endif

    init_size  =  1*K  - slack, // Size of first chunk

    medium_size= 10*K  - slack, // Size of medium-sized chunk

    size       = 32*K  - slack, // Default size of an Arena chunk (following the first)

    non_pool_size = init_size + 32 // An initial size which is not one of above

  };

  void chop();                  // Chop this chunk

  void next_chop();             // Chop next chunk

  static size_t aligned_overhead_size(void) { return ARENA_ALIGN(sizeof(Chunk)); }

  size_t length() const         { return _len;  }

  Chunk* next() const           { return _next;  }

  void set_next(Chunk* n)       { _next = n;  }

  // Boundaries of data area (possibly unused)

  char* bottom() const          { return ((char*) this) + aligned_overhead_size();  }

  char* top()    const          { return bottom() + _len; }

  bool contains(char* p) const  { return bottom() <= p && p <= top(); }

  // Start the chunk_pool cleaner task

  static void start_chunk_pool_cleaner_task();

  static void clean_chunk_pool();

};

//------------------------------Arena------------------------------------------

// Fast allocation of memory

class Arena: public CHeapObj {

protected:

  friend class ResourceMark;

  friend class HandleMark;

  friend class NoHandleMark;

  Chunk *_first;                // First chunk

  Chunk *_chunk;                // current chunk

  char *_hwm, *_max;            // High water mark and max in current chunk

  void* grow(size_t x);         // Get a new Chunk of at least size x

  NOT_PRODUCT(size_t _size_in_bytes;) // Size of arena (used for memory usage tracing)

  NOT_PRODUCT(static size_t _bytes_allocated;) // total #bytes allocated since start

  friend class AllocStats;

  debug_only(void* malloc(size_t size);)

  debug_only(void* internal_malloc_4(size_t x);)

 public:

  Arena();

  Arena(size_t init_size);

  Arena(Arena *old);

  ~Arena();

  void  destruct_contents();

  char* hwm() const             { return _hwm; }

  // Fast allocate in the arena.  Common case is: pointer test + increment.

  void* Amalloc(size_t x) {

    assert(is_power_of_2(ARENA_AMALLOC_ALIGNMENT) , "should be a power of 2");

    x = ARENA_ALIGN(x);

    debug_only(if (UseMallocOnly) return malloc(x);)

    NOT_PRODUCT(_bytes_allocated += x);

    if (_hwm + x > _max) {

      return grow(x);

    } else {

      char *old = _hwm;

      _hwm += x;

      return old;

    }

  }

  // Further assume size is padded out to words

  void *Amalloc_4(size_t x) {

    assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );

    debug_only(if (UseMallocOnly) return malloc(x);)

    NOT_PRODUCT(_bytes_allocated += x);

    if (_hwm + x > _max) {

      return grow(x);

    } else {

      char *old = _hwm;

      _hwm += x;

      return old;

    }

  }

  // Allocate with 'double' alignment. It is 8 bytes on sparc.

  // In other cases Amalloc_D() should be the same as Amalloc_4().

  void* Amalloc_D(size_t x) {

    assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );

    debug_only(if (UseMallocOnly) return malloc(x);)

#if defined(SPARC) && !defined(_LP64)

#define DALIGN_M1 7

    size_t delta = (((size_t)_hwm + DALIGN_M1) & ~DALIGN_M1) - (size_t)_hwm;

    x += delta;

#endif

    NOT_PRODUCT(_bytes_allocated += x);

    if (_hwm + x > _max) {

      return grow(x); // grow() returns a result aligned >= 8 bytes.

    } else {

      char *old = _hwm;

      _hwm += x;

#if defined(SPARC) && !defined(_LP64)

      old += delta; // align to 8-bytes

#endif

      return old;

    }

  }

  // Fast delete in area.  Common case is: NOP (except for storage reclaimed)

  void Afree(void *ptr, size_t size) {

#ifdef ASSERT

    if (ZapResourceArea) memset(ptr, badResourceValue, size); // zap freed memory

    if (UseMallocOnly) return;

#endif

    if (((char*)ptr) + size == _hwm) _hwm = (char*)ptr;

  }

  void *Arealloc( void *old_ptr, size_t old_size, size_t new_size );

  // Move contents of this arena into an empty arena

  Arena *move_contents(Arena *empty_arena);

  // Determine if pointer belongs to this Arena or not.

  bool contains( const void *ptr ) const;

  // Total of all chunks in use (not thread-safe)

  size_t used() const;

  // Total # of bytes used

  size_t size_in_bytes() const         NOT_PRODUCT({  return _size_in_bytes; }) PRODUCT_RETURN0;

  void set_size_in_bytes(size_t size)  NOT_PRODUCT({ _size_in_bytes = size;  }) PRODUCT_RETURN;

  static void free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2)  PRODUCT_RETURN;

  static void free_all(char** start, char** end)                                     PRODUCT_RETURN;

private:

  // Reset this Arena to empty, access will trigger grow if necessary

  void   reset(void) {

    _first = _chunk = NULL;

    _hwm = _max = NULL;

  }

};

// One of the following macros must be used when allocating

// an array or object from an arena

  NEW_ARENA_ARRAY(arena, type, 1)

//%note allocation_1

extern char* resource_allocate_bytes(size_t size);

extern char* resource_allocate_bytes(Thread* thread, size_t size);

extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size);

extern void resource_free_bytes( char *old, size_t size );

//----------------------------------------------------------------------

// Base class for objects allocated in the resource area per default.

// Optionally, objects may be allocated on the C heap with

// new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena)

// ResourceObj's can be allocated within other objects, but don't use

// new or delete (allocation_type is unknown).  If new is used to allocate,

// use delete to deallocate.

class ResourceObj ALLOCATION_SUPER_CLASS_SPEC {

 public:

  enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 };

  static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN;

#ifdef ASSERT

 private:

  // When this object is allocated on stack the new() operator is not

  // called but garbage on stack may look like a valid allocation_type.

  // Store negated 'this' pointer when new() is called to distinguish cases.

  uintptr_t _allocation;

 public:

  allocation_type get_allocation_type() const;

  bool allocated_on_stack()    const { return get_allocation_type() == STACK_OR_EMBEDDED; }

  bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; }

  bool allocated_on_C_heap()   const { return get_allocation_type() == C_HEAP; }

  bool allocated_on_arena()    const { return get_allocation_type() == ARENA; }

  ResourceObj(); // default construtor

  ResourceObj(const ResourceObj& r); // default copy construtor

  ResourceObj& operator=(const ResourceObj& r); // default copy assignment

  ~ResourceObj();

#endif // ASSERT

 public:

  void* operator new(size_t size, allocation_type type);

  void* operator new(size_t size, Arena *arena) {

      address res = (address)arena->Amalloc(size);

      DEBUG_ONLY(set_allocation_type(res, ARENA);)

      return res;

  }

  void* operator new(size_t size) {

      address res = (address)resource_allocate_bytes(size);

      DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)

      return res;

  }

  void  operator delete(void* p);

};

// One of the following macros must be used when allocating an array

// or object to determine whether it should reside in the C heap on in

// the resource area.

#define NEW_RESOURCE_ARRAY(type, size)\

  (type*) resource_allocate_bytes((size) * sizeof(type))

#define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\

  (type*) resource_allocate_bytes(thread, (size) * sizeof(type))

#define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\

  (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) )

#define FREE_RESOURCE_ARRAY(type, old, size)\

  resource_free_bytes((char*)(old), (size) * sizeof(type))

#define FREE_FAST(old)\

    /* nop */

#define NEW_RESOURCE_OBJ(type)\

  NEW_RESOURCE_ARRAY(type, 1)

#define NEW_C_HEAP_ARRAY(type, size)\

  (type*) (AllocateHeap((size) * sizeof(type), XSTR(type) " in " __FILE__))

#define REALLOC_C_HEAP_ARRAY(type, old, size)\

  (type*) (ReallocateHeap((char*)old, (size) * sizeof(type), XSTR(type) " in " __FILE__))

#define FREE_C_HEAP_ARRAY(type,old) \

  FreeHeap((char*)(old))

#define NEW_C_HEAP_OBJ(type)\

  NEW_C_HEAP_ARRAY(type, 1)

extern bool warn_new_operator;

// for statistics

#ifndef PRODUCT

class AllocStats : StackObj {

  int    start_mallocs, start_frees;

  size_t start_malloc_bytes, start_res_bytes;

 public:

  AllocStats();

  int    num_mallocs();    // since creation of receiver

  size_t alloc_bytes();

  size_t resource_bytes();

  int    num_frees();

  void   print();

};

#endif

//------------------------------ReallocMark---------------------------------

// Code which uses REALLOC_RESOURCE_ARRAY should check an associated

// ReallocMark, which is declared in the same scope as the reallocated

// pointer.  Any operation that could __potentially__ cause a reallocation

// should check the ReallocMark.

class ReallocMark: public StackObj {

protected:

  NOT_PRODUCT(int _nesting;)

public:

  ReallocMark()   PRODUCT_RETURN;

  void check()    PRODUCT_RETURN;

};