0N/A

1879N/A#ifndef SHARE_VM_MEMORY_HEAP_HPP

1879N/A#define SHARE_VM_MEMORY_HEAP_HPP

1879N/A

1879N/A#include "memory/allocation.hpp"

1879N/A#include "runtime/virtualspace.hpp"

1879N/A

0N/A

0N/Aclass HeapBlock VALUE_OBJ_CLASS_SPEC {

0N/A friend class VMStructs;

0N/A

0N/A public:

0N/A struct Header {

0N/A size_t _length; // the length in segments

0N/A bool _used; // Used bit

0N/A };

0N/A

0N/A protected:

0N/A union {

0N/A Header _header;

0N/A int64_t _padding[ (sizeof(Header) + sizeof(int64_t)-1) / sizeof(int64_t) ];

0N/A // pad to 0 mod 8

0N/A };

0N/A

0N/A public:

0N/A // Initialization

0N/A void initialize(size_t length) { _header._length = length; set_used(); }

0N/A

0N/A // Accessors

0N/A void* allocated_space() const { return (void*)(this + 1); }

0N/A size_t length() const { return _header._length; }

0N/A

0N/A // Used/free

0N/A void set_used() { _header._used = true; }

0N/A void set_free() { _header._used = false; }

0N/A bool free() { return !_header._used; }

0N/A};

0N/A

0N/Aclass FreeBlock: public HeapBlock {

0N/A friend class VMStructs;

0N/A protected:

0N/A FreeBlock* _link;

0N/A

0N/A public:

0N/A // Initialization

0N/A void initialize(size_t length) { HeapBlock::initialize(length); _link= NULL; }

0N/A

0N/A // Merging

0N/A void set_length(size_t l) { _header._length = l; }

0N/A

0N/A // Accessors

0N/A FreeBlock* link() const { return _link; }

0N/A void set_link(FreeBlock* link) { _link = link; }

0N/A};

0N/A

3863N/Aclass CodeHeap : public CHeapObj<mtCode> {

0N/A friend class VMStructs;

0N/A private:

0N/A VirtualSpace _memory; // the memory holding the blocks

0N/A VirtualSpace _segmap; // the memory holding the segment map

0N/A

0N/A size_t _number_of_committed_segments;

0N/A size_t _number_of_reserved_segments;

0N/A size_t _segment_size;

0N/A int _log2_segment_size;

0N/A

0N/A size_t _next_segment;

0N/A

0N/A FreeBlock* _freelist;

0N/A size_t _free_segments; // No. of segments in freelist

0N/A

0N/A // Helper functions

0N/A size_t number_of_segments(size_t size) const { return (size + _segment_size - 1) >> _log2_segment_size; }

0N/A size_t size(size_t number_of_segments) const { return number_of_segments << _log2_segment_size; }

0N/A

0N/A size_t segment_for(void* p) const { return ((char*)p - _memory.low()) >> _log2_segment_size; }

0N/A HeapBlock* block_at(size_t i) const { return (HeapBlock*)(_memory.low() + (i << _log2_segment_size)); }

0N/A

0N/A void mark_segmap_as_free(size_t beg, size_t end);

0N/A void mark_segmap_as_used(size_t beg, size_t end);

0N/A

0N/A // Freelist management helpers

0N/A FreeBlock* following_block(FreeBlock *b);

0N/A void insert_after(FreeBlock* a, FreeBlock* b);

0N/A void merge_right (FreeBlock* a);

0N/A

0N/A // Toplevel freelist management

0N/A void add_to_freelist(HeapBlock *b);

0N/A FreeBlock* search_freelist(size_t length);

0N/A

0N/A // Iteration helpers

0N/A void* next_free(HeapBlock* b) const;

0N/A HeapBlock* first_block() const;

0N/A HeapBlock* next_block(HeapBlock* b) const;

0N/A HeapBlock* block_start(void* p) const;

0N/A

0N/A // to perform additional actions on creation of executable code

0N/A void on_code_mapping(char* base, size_t size);

0N/A

0N/A public:

0N/A CodeHeap();

0N/A

0N/A // Heap extents

0N/A bool reserve(size_t reserved_size, size_t committed_size, size_t segment_size);

0N/A void release(); // releases all allocated memory

0N/A bool expand_by(size_t size); // expands commited memory by size

0N/A void shrink_by(size_t size); // shrinks commited memory by size

0N/A void clear(); // clears all heap contents

0N/A

0N/A // Memory allocation

0N/A void* allocate (size_t size); // allocates a block of size or returns NULL

0N/A void deallocate(void* p); // deallocates a block

0N/A

0N/A // Attributes

0N/A void* begin() const { return _memory.low (); }

0N/A void* end() const { return _memory.high(); }

0N/A bool contains(void* p) const { return begin() <= p && p < end(); }

0N/A void* find_start(void* p) const; // returns the block containing p or NULL

0N/A size_t alignment_unit() const; // alignment of any block

0N/A size_t alignment_offset() const; // offset of first byte of any block, within the enclosing alignment unit

0N/A static size_t header_size(); // returns the header size for each heap block

0N/A

0N/A // Returns reserved area high and low addresses

0N/A char *low_boundary() const { return _memory.low_boundary (); }

1827N/A char *high() const { return _memory.high(); }

0N/A char *high_boundary() const { return _memory.high_boundary(); }

0N/A

0N/A // Iteration

0N/A

0N/A // returns the first block or NULL

0N/A void* first() const { return next_free(first_block()); }

0N/A // returns the next block given a block p or NULL

0N/A void* next(void* p) const { return next_free(next_block(block_start(p))); }

0N/A

0N/A // Statistics

0N/A size_t capacity() const;

0N/A size_t max_capacity() const;

0N/A size_t allocated_capacity() const;

0N/A size_t unallocated_capacity() const { return max_capacity() - allocated_capacity(); }

1979N/A size_t largest_free_block() const;

0N/A

0N/A // Debugging

0N/A void verify();

0N/A void print() PRODUCT_RETURN;

0N/A};

1879N/A

1879N/A#endif // SHARE_VM_MEMORY_HEAP_HPP