Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1997-2006 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.

  *

  */

 // Closure for iterating over BitMaps

 class BitMapClosure VALUE_OBJ_CLASS_SPEC {

  public:

   // Callback when bit in map is set

   virtual void do_bit(size_t offset) = 0;

 };

 // Operations for bitmaps represented as arrays of unsigned 32- or 64-bit

 // integers (uintptr_t).

 //

 // Bit offsets are numbered from 0 to size-1

 class BitMap VALUE_OBJ_CLASS_SPEC {

   friend class BitMap2D;

  public:

   typedef size_t idx_t;         // Type used for bit and word indices.

   // Hints for range sizes.

   typedef enum {

     unknown_range, small_range, large_range

   } RangeSizeHint;

  private:

   idx_t* _map;     // First word in bitmap

   idx_t  _size;    // Size of bitmap (in bits)

   // Puts the given value at the given offset, using resize() to size

   // the bitmap appropriately if needed using factor-of-two expansion.

   void at_put_grow(idx_t index, bool value);

  protected:

   // Return the position of bit within the word that contains it (e.g., if

   // bitmap words are 32 bits, return a number 0 <= n <= 31).

   static idx_t bit_in_word(idx_t bit) { return bit & (BitsPerWord - 1); }

   // Return a mask that will select the specified bit, when applied to the word

   // containing the bit.

   static idx_t bit_mask(idx_t bit)    { return (idx_t)1 << bit_in_word(bit); }

   // Return the index of the word containing the specified bit.

   static idx_t word_index(idx_t bit)  { return bit >> LogBitsPerWord; }

   // Return the bit number of the first bit in the specified word.

   static idx_t bit_index(idx_t word)  { return word << LogBitsPerWord; }

   // Return the array of bitmap words, or a specific word from it.

   idx_t* map() const           { return _map; }

   idx_t  map(idx_t word) const { return _map[word]; }

   // Return a pointer to the word containing the specified bit.

   idx_t* word_addr(idx_t bit) const { return map() + word_index(bit); }

   // Set a word to a specified value or to all ones; clear a word.

   void set_word  (idx_t word, idx_t val) { _map[word] = val; }

   void set_word  (idx_t word)            { set_word(word, ~(uintptr_t)0); }

   void clear_word(idx_t word)            { _map[word] = 0; }

   // Utilities for ranges of bits.  Ranges are half-open [beg, end).

   // Ranges within a single word.

   inline idx_t inverted_bit_mask_for_range(idx_t beg, idx_t end) const;

   inline void  set_range_within_word      (idx_t beg, idx_t end);

   inline void  clear_range_within_word    (idx_t beg, idx_t end);

   inline void  par_put_range_within_word  (idx_t beg, idx_t end, bool value);

   // Ranges spanning entire words.

   inline void      set_range_of_words         (idx_t beg, idx_t end);

   inline void      clear_range_of_words       (idx_t beg, idx_t end);

   inline void      set_large_range_of_words   (idx_t beg, idx_t end);

   inline void      clear_large_range_of_words (idx_t beg, idx_t end);

   // The index of the first full word in a range.

   inline idx_t word_index_round_up(idx_t bit) const;

   // Verification, statistics.

   void verify_index(idx_t index) const {

     assert(index < _size, "BitMap index out of bounds");

   }

   void verify_range(idx_t beg_index, idx_t end_index) const {

 #ifdef ASSERT

     assert(beg_index <= end_index, "BitMap range error");

     // Note that [0,0) and [size,size) are both valid ranges.

     if (end_index != _size)  verify_index(end_index);

 #endif

   }

  public:

   // Constructs a bitmap with no map, and size 0.

   BitMap() : _map(NULL), _size(0) {}

   // Construction

   BitMap(idx_t* map, idx_t size_in_bits);

   // Allocates necessary data structure in resource area

   BitMap(idx_t size_in_bits);

   void set_map(idx_t* map)          { _map = map; }

   void set_size(idx_t size_in_bits) { _size = size_in_bits; }

   // Allocates necessary data structure in resource area.

   // Preserves state currently in bit map by copying data.

   // Zeros any newly-addressable bits.

   // Does not perform any frees (i.e., of current _map).

   void resize(idx_t size_in_bits);

   // Accessing

   idx_t size() const                    { return _size; }

   idx_t size_in_words() const           {

     return word_index(size() + BitsPerWord - 1);

   }

   bool at(idx_t index) const {

     verify_index(index);

     return (*word_addr(index) & bit_mask(index)) != 0;

   }

   // Align bit index up or down to the next bitmap word boundary, or check

   // alignment.

   static idx_t word_align_up(idx_t bit) {

     return align_size_up(bit, BitsPerWord);

   }

   static idx_t word_align_down(idx_t bit) {

     return align_size_down(bit, BitsPerWord);

   }

   static bool is_word_aligned(idx_t bit) {

     return word_align_up(bit) == bit;

   }

   // Set or clear the specified bit.

   inline void set_bit(idx_t bit);

   inline void clear_bit(idx_t bit);

   // Atomically set or clear the specified bit.

   inline bool par_set_bit(idx_t bit);

   inline bool par_clear_bit(idx_t bit);

   // Put the given value at the given offset. The parallel version

   // will CAS the value into the bitmap and is quite a bit slower.

   // The parallel version also returns a value indicating if the

   // calling thread was the one that changed the value of the bit.

   void at_put(idx_t index, bool value);

   bool par_at_put(idx_t index, bool value);

   // Update a range of bits.  Ranges are half-open [beg, end).

   void set_range   (idx_t beg, idx_t end);

   void clear_range (idx_t beg, idx_t end);

   void set_large_range   (idx_t beg, idx_t end);

   void clear_large_range (idx_t beg, idx_t end);

   void at_put_range(idx_t beg, idx_t end, bool value);

   void par_at_put_range(idx_t beg, idx_t end, bool value);

   void at_put_large_range(idx_t beg, idx_t end, bool value);

   void par_at_put_large_range(idx_t beg, idx_t end, bool value);

   // Update a range of bits, using a hint about the size.  Currently only

   // inlines the predominant case of a 1-bit range.  Works best when hint is a

   // compile-time constant.

   inline void set_range(idx_t beg, idx_t end, RangeSizeHint hint);

   inline void clear_range(idx_t beg, idx_t end, RangeSizeHint hint);

   inline void par_set_range(idx_t beg, idx_t end, RangeSizeHint hint);

   inline void par_clear_range  (idx_t beg, idx_t end, RangeSizeHint hint);

   // Clearing

   void clear();

   void clear_large();

   // Iteration support

   void iterate(BitMapClosure* blk, idx_t leftIndex, idx_t rightIndex);

   inline void iterate(BitMapClosure* blk) {

     // call the version that takes an interval

     iterate(blk, 0, size());

   }

   // Looking for 1's and 0's to the "right"

   idx_t get_next_one_offset (idx_t l_index, idx_t r_index) const;

   idx_t get_next_zero_offset(idx_t l_index, idx_t r_index) const;

   idx_t get_next_one_offset(idx_t offset) const {

     return get_next_one_offset(offset, size());

   }

   idx_t get_next_zero_offset(idx_t offset) const {

     return get_next_zero_offset(offset, size());

   }

   // Find the next one bit in the range [beg_bit, end_bit), or return end_bit if

   // no one bit is found.  Equivalent to get_next_one_offset(), but inline for

   // use in performance-critical code.

   inline idx_t find_next_one_bit(idx_t beg_bit, idx_t end_bit) const;

   // Set operations.

   void set_union(BitMap bits);

   void set_difference(BitMap bits);

   void set_intersection(BitMap bits);

   // Returns true iff "this" is a superset of "bits".

   bool contains(const BitMap bits) const;

   // Returns true iff "this and "bits" have a non-empty intersection.

   bool intersects(const BitMap bits) const;

   // Returns result of whether this map changed

   // during the operation

   bool set_union_with_result(BitMap bits);

   bool set_difference_with_result(BitMap bits);

   bool set_intersection_with_result(BitMap bits);

   void set_from(BitMap bits);

   bool is_same(BitMap bits);

   // Test if all bits are set or cleared

   bool is_full() const;

   bool is_empty() const;

 #ifndef PRODUCT

  public:

   // Printing

   void print_on(outputStream* st) const;

 #endif

 };

 inline void BitMap::set_bit(idx_t bit) {

   verify_index(bit);

   *word_addr(bit) |= bit_mask(bit);

 }

 inline void BitMap::clear_bit(idx_t bit) {

   verify_index(bit);

   *word_addr(bit) &= ~bit_mask(bit);

 }

 inline void BitMap::set_range(idx_t beg, idx_t end, RangeSizeHint hint) {

   if (hint == small_range && end - beg == 1) {

     set_bit(beg);

   } else {

     if (hint == large_range) {

       set_large_range(beg, end);

     } else {

       set_range(beg, end);

     }

   }

 }

 inline void BitMap::clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {

   if (hint == small_range && end - beg == 1) {

     clear_bit(beg);

   } else {

     if (hint == large_range) {

       clear_large_range(beg, end);

     } else {

       clear_range(beg, end);

     }

   }

 }

 inline void BitMap::par_set_range(idx_t beg, idx_t end, RangeSizeHint hint) {

   if (hint == small_range && end - beg == 1) {

     par_at_put(beg, true);

   } else {

     if (hint == large_range) {

       par_at_put_large_range(beg, end, true);

     } else {

       par_at_put_range(beg, end, true);

     }

   }

 }

 // Convenience class wrapping BitMap which provides multiple bits per slot.

 class BitMap2D VALUE_OBJ_CLASS_SPEC {

  public:

   typedef size_t idx_t;         // Type used for bit and word indices.

  private:

   BitMap _map;

   idx_t  _bits_per_slot;

   idx_t bit_index(idx_t slot_index, idx_t bit_within_slot_index) const {

     return slot_index * _bits_per_slot + bit_within_slot_index;

   }

   void verify_bit_within_slot_index(idx_t index) const {

     assert(index < _bits_per_slot, "bit_within_slot index out of bounds");

   }

  public:

   // Construction. bits_per_slot must be greater than 0.

   BitMap2D(uintptr_t* map, idx_t size_in_slots, idx_t bits_per_slot);

   // Allocates necessary data structure in resource area. bits_per_slot must be greater than 0.

   BitMap2D(idx_t size_in_slots, idx_t bits_per_slot);

   idx_t size_in_bits() {

     return _map.size();

   }

   // Returns number of full slots that have been allocated

   idx_t size_in_slots() {

     // Round down

     return _map.size() / _bits_per_slot;

   }

   bool is_valid_index(idx_t slot_index, idx_t bit_within_slot_index) {

     verify_bit_within_slot_index(bit_within_slot_index);

     return (bit_index(slot_index, bit_within_slot_index) < size_in_bits());

   }

   bool at(idx_t slot_index, idx_t bit_within_slot_index) const {

     verify_bit_within_slot_index(bit_within_slot_index);

     return _map.at(bit_index(slot_index, bit_within_slot_index));

   }

   void set_bit(idx_t slot_index, idx_t bit_within_slot_index) {

     verify_bit_within_slot_index(bit_within_slot_index);

     _map.set_bit(bit_index(slot_index, bit_within_slot_index));

   }

   void clear_bit(idx_t slot_index, idx_t bit_within_slot_index) {

     verify_bit_within_slot_index(bit_within_slot_index);

     _map.clear_bit(bit_index(slot_index, bit_within_slot_index));

   }

   void at_put(idx_t slot_index, idx_t bit_within_slot_index, bool value) {

     verify_bit_within_slot_index(bit_within_slot_index);

     _map.at_put(bit_index(slot_index, bit_within_slot_index), value);

   }

   void at_put_grow(idx_t slot_index, idx_t bit_within_slot_index, bool value) {

     verify_bit_within_slot_index(bit_within_slot_index);

     _map.at_put_grow(bit_index(slot_index, bit_within_slot_index), value);

   }

   void clear() {

     _map.clear();

   }

 };

 inline void BitMap::set_range_of_words(idx_t beg, idx_t end) {

   uintptr_t* map = _map;

   for (idx_t i = beg; i < end; ++i) map[i] = ~(uintptr_t)0;

 }

 inline void BitMap::clear_range_of_words(idx_t beg, idx_t end) {

   uintptr_t* map = _map;

   for (idx_t i = beg; i < end; ++i) map[i] = 0;

 }

 inline void BitMap::clear() {

   clear_range_of_words(0, size_in_words());

 }

 inline void BitMap::par_clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {

   if (hint == small_range && end - beg == 1) {

     par_at_put(beg, false);

   } else {

     if (hint == large_range) {

       par_at_put_large_range(beg, end, false);

     } else {

       par_at_put_range(beg, end, false);

     }

   }

 }