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.

  *

  */

 # include "incls/_precompiled.incl"

 # include "incls/_bitMap.cpp.incl"

 BitMap::BitMap(idx_t* map, idx_t size_in_bits) {

   assert(size_in_bits >= 0, "just checking");

   _map = map;

   _size = size_in_bits;

 }

 BitMap::BitMap(idx_t size_in_bits) {

   assert(size_in_bits >= 0, "just checking");

   _size = size_in_bits;

   _map = NEW_RESOURCE_ARRAY(idx_t, size_in_words());

 }

 void BitMap::resize(idx_t size_in_bits) {

   assert(size_in_bits >= 0, "just checking");

   size_t old_size_in_words = size_in_words();

   uintptr_t* old_map = map();

   _size = size_in_bits;

   size_t new_size_in_words = size_in_words();

   _map = NEW_RESOURCE_ARRAY(idx_t, new_size_in_words);

   Copy::disjoint_words((HeapWord*) old_map, (HeapWord*) _map, MIN2(old_size_in_words, new_size_in_words));

   if (new_size_in_words > old_size_in_words) {

     clear_range_of_words(old_size_in_words, size_in_words());

   }

 }

 // Returns a bit mask for a range of bits [beg, end) within a single word.  Each

 // bit in the mask is 0 if the bit is in the range, 1 if not in the range.  The

 // returned mask can be used directly to clear the range, or inverted to set the

 // range.  Note:  end must not be 0.

 inline BitMap::idx_t

 BitMap::inverted_bit_mask_for_range(idx_t beg, idx_t end) const {

   assert(end != 0, "does not work when end == 0");

   assert(beg == end || word_index(beg) == word_index(end - 1),

          "must be a single-word range");

   idx_t mask = bit_mask(beg) - 1;       // low (right) bits

   if (bit_in_word(end) != 0) {

     mask |= ~(bit_mask(end) - 1);       // high (left) bits

   }

   return mask;

 }

 void BitMap::set_range_within_word(idx_t beg, idx_t end) {

   // With a valid range (beg <= end), this test ensures that end != 0, as

   // required by inverted_bit_mask_for_range.  Also avoids an unnecessary write.

   if (beg != end) {

     idx_t mask = inverted_bit_mask_for_range(beg, end);

     *word_addr(beg) |= ~mask;

   }

 }

 void BitMap::clear_range_within_word(idx_t beg, idx_t end) {

   // With a valid range (beg <= end), this test ensures that end != 0, as

   // required by inverted_bit_mask_for_range.  Also avoids an unnecessary write.

   if (beg != end) {

     idx_t mask = inverted_bit_mask_for_range(beg, end);

     *word_addr(beg) &= mask;

   }

 }

 void BitMap::par_put_range_within_word(idx_t beg, idx_t end, bool value) {

   assert(value == 0 || value == 1, "0 for clear, 1 for set");

   // With a valid range (beg <= end), this test ensures that end != 0, as

   // required by inverted_bit_mask_for_range.  Also avoids an unnecessary write.

   if (beg != end) {

     intptr_t* pw  = (intptr_t*)word_addr(beg);

     intptr_t  w   = *pw;

     intptr_t  mr  = (intptr_t)inverted_bit_mask_for_range(beg, end);

     intptr_t  nw  = value ? (w | ~mr) : (w & mr);

     while (true) {

       intptr_t res = Atomic::cmpxchg_ptr(nw, pw, w);

       if (res == w) break;

       w  = *pw;

       nw = value ? (w | ~mr) : (w & mr);

     }

   }

 }

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

   memset(_map + beg, ~(unsigned char)0, (end - beg) * sizeof(uintptr_t));

 }

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

   memset(_map + beg, 0, (end - beg) * sizeof(uintptr_t));

 }

 inline BitMap::idx_t BitMap::word_index_round_up(idx_t bit) const {

   idx_t bit_rounded_up = bit + (BitsPerWord - 1);

   // Check for integer arithmetic overflow.

   return bit_rounded_up > bit ? word_index(bit_rounded_up) : size_in_words();

 }

 void BitMap::set_range(idx_t beg, idx_t end) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   if (beg_full_word < end_full_word) {

     // The range includes at least one full word.

     set_range_within_word(beg, bit_index(beg_full_word));

     set_range_of_words(beg_full_word, end_full_word);

     set_range_within_word(bit_index(end_full_word), end);

   } else {

     // The range spans at most 2 partial words.

     idx_t boundary = MIN2(bit_index(beg_full_word), end);

     set_range_within_word(beg, boundary);

     set_range_within_word(boundary, end);

   }

 }

 void BitMap::clear_range(idx_t beg, idx_t end) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   if (beg_full_word < end_full_word) {

     // The range includes at least one full word.

     clear_range_within_word(beg, bit_index(beg_full_word));

     clear_range_of_words(beg_full_word, end_full_word);

     clear_range_within_word(bit_index(end_full_word), end);

   } else {

     // The range spans at most 2 partial words.

     idx_t boundary = MIN2(bit_index(beg_full_word), end);

     clear_range_within_word(beg, boundary);

     clear_range_within_word(boundary, end);

   }

 }

 void BitMap::set_large_range(idx_t beg, idx_t end) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   assert(end_full_word - beg_full_word >= 32,

          "the range must include at least 32 bytes");

   // The range includes at least one full word.

   set_range_within_word(beg, bit_index(beg_full_word));

   set_large_range_of_words(beg_full_word, end_full_word);

   set_range_within_word(bit_index(end_full_word), end);

 }

 void BitMap::clear_large_range(idx_t beg, idx_t end) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   assert(end_full_word - beg_full_word >= 32,

          "the range must include at least 32 bytes");

   // The range includes at least one full word.

   clear_range_within_word(beg, bit_index(beg_full_word));

   clear_large_range_of_words(beg_full_word, end_full_word);

   clear_range_within_word(bit_index(end_full_word), end);

 }

 void BitMap::at_put(idx_t offset, bool value) {

   if (value) {

     set_bit(offset);

   } else {

     clear_bit(offset);

   }

 }

 // Return true to indicate that this thread changed

 // the bit, false to indicate that someone else did.

 // In either case, the requested bit is in the

 // requested state some time during the period that

 // this thread is executing this call. More importantly,

 // if no other thread is executing an action to

 // change the requested bit to a state other than

 // the one that this thread is trying to set it to,

 // then the the bit is in the expected state

 // at exit from this method. However, rather than

 // make such a strong assertion here, based on

 // assuming such constrained use (which though true

 // today, could change in the future to service some

 // funky parallel algorithm), we encourage callers

 // to do such verification, as and when appropriate.

 bool BitMap::par_at_put(idx_t bit, bool value) {

   return value ? par_set_bit(bit) : par_clear_bit(bit);

 }

 void BitMap::at_put_grow(idx_t offset, bool value) {

   if (offset >= size()) {

     resize(2 * MAX2(size(), offset));

   }

   at_put(offset, value);

 }

 void BitMap::at_put_range(idx_t start_offset, idx_t end_offset, bool value) {

   if (value) {

     set_range(start_offset, end_offset);

   } else {

     clear_range(start_offset, end_offset);

   }

 }

 void BitMap::par_at_put_range(idx_t beg, idx_t end, bool value) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   if (beg_full_word < end_full_word) {

     // The range includes at least one full word.

     par_put_range_within_word(beg, bit_index(beg_full_word), value);

     if (value) {

       set_range_of_words(beg_full_word, end_full_word);

     } else {

       clear_range_of_words(beg_full_word, end_full_word);

     }

     par_put_range_within_word(bit_index(end_full_word), end, value);

   } else {

     // The range spans at most 2 partial words.

     idx_t boundary = MIN2(bit_index(beg_full_word), end);

     par_put_range_within_word(beg, boundary, value);

     par_put_range_within_word(boundary, end, value);

   }

 }

 void BitMap::at_put_large_range(idx_t beg, idx_t end, bool value) {

   if (value) {

     set_large_range(beg, end);

   } else {

     clear_large_range(beg, end);

   }

 }

 void BitMap::par_at_put_large_range(idx_t beg, idx_t end, bool value) {

   verify_range(beg, end);

   idx_t beg_full_word = word_index_round_up(beg);

   idx_t end_full_word = word_index(end);

   assert(end_full_word - beg_full_word >= 32,

          "the range must include at least 32 bytes");

   // The range includes at least one full word.

   par_put_range_within_word(beg, bit_index(beg_full_word), value);

   if (value) {

     set_large_range_of_words(beg_full_word, end_full_word);

   } else {

     clear_large_range_of_words(beg_full_word, end_full_word);

   }

   par_put_range_within_word(bit_index(end_full_word), end, value);

 }

 bool BitMap::contains(const BitMap other) const {

   assert(size() == other.size(), "must have same size");

   uintptr_t* dest_map = map();

   uintptr_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size_in_words(); index++) {

     uintptr_t word_union = dest_map[index] | other_map[index];

     // If this has more bits set than dest_map[index], then other is not a

     // subset.

     if (word_union != dest_map[index]) return false;

   }

   return true;

 }

 bool BitMap::intersects(const BitMap other) const {

   assert(size() == other.size(), "must have same size");

   uintptr_t* dest_map = map();

   uintptr_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size_in_words(); index++) {

     if ((dest_map[index] & other_map[index]) != 0) return true;

   }

   // Otherwise, no intersection.

   return false;

 }

 void BitMap::set_union(BitMap other) {

   assert(size() == other.size(), "must have same size");

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size_in_words(); index++) {

     dest_map[index] = dest_map[index] | other_map[index];

   }

 }

 void BitMap::set_difference(BitMap other) {

   assert(size() == other.size(), "must have same size");

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size_in_words(); index++) {

     dest_map[index] = dest_map[index] & ~(other_map[index]);

   }

 }

 void BitMap::set_intersection(BitMap other) {

   assert(size() == other.size(), "must have same size");

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     dest_map[index]  = dest_map[index] & other_map[index];

   }

 }

 bool BitMap::set_union_with_result(BitMap other) {

   assert(size() == other.size(), "must have same size");

   bool changed = false;

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     idx_t temp = map(index) | other_map[index];

     changed = changed || (temp != map(index));

     map()[index] = temp;

   }

   return changed;

 }

 bool BitMap::set_difference_with_result(BitMap other) {

   assert(size() == other.size(), "must have same size");

   bool changed = false;

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     idx_t temp = dest_map[index] & ~(other_map[index]);

     changed = changed || (temp != dest_map[index]);

     dest_map[index] = temp;

   }

   return changed;

 }

 bool BitMap::set_intersection_with_result(BitMap other) {

   assert(size() == other.size(), "must have same size");

   bool changed = false;

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     idx_t orig = dest_map[index];

     idx_t temp = orig & other_map[index];

     changed = changed || (temp != orig);

     dest_map[index]  = temp;

   }

   return changed;

 }

 void BitMap::set_from(BitMap other) {

   assert(size() == other.size(), "must have same size");

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     dest_map[index] = other_map[index];

   }

 }

 bool BitMap::is_same(BitMap other) {

   assert(size() == other.size(), "must have same size");

   idx_t* dest_map = map();

   idx_t* other_map = other.map();

   idx_t size = size_in_words();

   for (idx_t index = 0; index < size; index++) {

     if (dest_map[index] != other_map[index]) return false;

   }

   return true;

 }

 bool BitMap::is_full() const {

   uintptr_t* word = map();

   idx_t rest = size();

   for (; rest >= (idx_t) BitsPerWord; rest -= BitsPerWord) {

     if (*word != (uintptr_t) AllBits) return false;

     word++;

   }

   return rest == 0 || (*word | ~right_n_bits((int)rest)) == (uintptr_t) AllBits;

 }

 bool BitMap::is_empty() const {

   uintptr_t* word = map();

   idx_t rest = size();

   for (; rest >= (idx_t) BitsPerWord; rest -= BitsPerWord) {

     if (*word != (uintptr_t) NoBits) return false;

     word++;

   }

   return rest == 0 || (*word & right_n_bits((int)rest)) == (uintptr_t) NoBits;

 }

 void BitMap::clear_large() {

   clear_large_range_of_words(0, size_in_words());

 }

 // Note that if the closure itself modifies the bitmap

 // then modifications in and to the left of the _bit_ being

 // currently sampled will not be seen. Note also that the

 // interval [leftOffset, rightOffset) is right open.

 void BitMap::iterate(BitMapClosure* blk, idx_t leftOffset, idx_t rightOffset) {

   verify_range(leftOffset, rightOffset);

   idx_t startIndex = word_index(leftOffset);

   idx_t endIndex   = MIN2(word_index(rightOffset) + 1, size_in_words());

   for (idx_t index = startIndex, offset = leftOffset;

        offset < rightOffset && index < endIndex;

        offset = (++index) << LogBitsPerWord) {

     idx_t rest = map(index) >> (offset & (BitsPerWord - 1));

     for (; offset < rightOffset && rest != (uintptr_t)NoBits; offset++) {

       if (rest & 1) {

         blk->do_bit(offset);

         //  resample at each closure application

         // (see, for instance, CMS bug 4525989)

         rest = map(index) >> (offset & (BitsPerWord -1));

         // XXX debugging: remove

         // The following assertion assumes that closure application

         // doesn't clear bits (may not be true in general, e.g. G1).

         assert(rest & 1,

                "incorrect shift or closure application can clear bits?");

       }

       rest = rest >> 1;

     }

   }

 }

 BitMap::idx_t BitMap::get_next_one_offset(idx_t l_offset,

                                           idx_t r_offset) const {

   assert(l_offset <= size(), "BitMap index out of bounds");

   assert(r_offset <= size(), "BitMap index out of bounds");

   assert(l_offset <= r_offset, "l_offset > r_offset ?");

   if (l_offset == r_offset) {

     return l_offset;

   }

   idx_t   index = word_index(l_offset);

   idx_t r_index = word_index(r_offset-1) + 1;

   idx_t res_offset = l_offset;

   // check bits including and to the _left_ of offset's position

   idx_t pos = bit_in_word(res_offset);

   idx_t res = map(index) >> pos;

   if (res != (uintptr_t)NoBits) {

     // find the position of the 1-bit

     for (; !(res & 1); res_offset++) {

       res = res >> 1;

     }

     assert(res_offset >= l_offset, "just checking");

     return MIN2(res_offset, r_offset);

   }

   // skip over all word length 0-bit runs

   for (index++; index < r_index; index++) {

     res = map(index);

     if (res != (uintptr_t)NoBits) {

       // found a 1, return the offset

       for (res_offset = index << LogBitsPerWord; !(res & 1);

            res_offset++) {

         res = res >> 1;

       }

       assert(res & 1, "tautology; see loop condition");

       assert(res_offset >= l_offset, "just checking");

       return MIN2(res_offset, r_offset);

     }

   }

   return r_offset;

 }

 BitMap::idx_t BitMap::get_next_zero_offset(idx_t l_offset,

                                            idx_t r_offset) const {

   assert(l_offset <= size(), "BitMap index out of bounds");

   assert(r_offset <= size(), "BitMap index out of bounds");

   assert(l_offset <= r_offset, "l_offset > r_offset ?");

   if (l_offset == r_offset) {

     return l_offset;

   }

   idx_t   index = word_index(l_offset);

   idx_t r_index = word_index(r_offset-1) + 1;

   idx_t res_offset = l_offset;

   // check bits including and to the _left_ of offset's position

   idx_t pos = res_offset & (BitsPerWord - 1);

   idx_t res = (map(index) >> pos) | left_n_bits((int)pos);

   if (res != (uintptr_t)AllBits) {

     // find the position of the 0-bit

     for (; res & 1; res_offset++) {

       res = res >> 1;

     }

     assert(res_offset >= l_offset, "just checking");

     return MIN2(res_offset, r_offset);

   }

   // skip over all word length 1-bit runs

   for (index++; index < r_index; index++) {

     res = map(index);

     if (res != (uintptr_t)AllBits) {

       // found a 0, return the offset

       for (res_offset = index << LogBitsPerWord; res & 1;

            res_offset++) {

         res = res >> 1;

       }

       assert(!(res & 1), "tautology; see loop condition");

       assert(res_offset >= l_offset, "just checking");

       return MIN2(res_offset, r_offset);

     }

   }

   return r_offset;

 }

 #ifndef PRODUCT

 void BitMap::print_on(outputStream* st) const {

   tty->print("Bitmap(%d):", size());

   for (idx_t index = 0; index < size(); index++) {

     tty->print("%c", at(index) ? '1' : '0');

   }

   tty->cr();

 }

 #endif

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

   : _bits_per_slot(bits_per_slot)

   , _map(map, size_in_slots * bits_per_slot)

 {

 }

 BitMap2D::BitMap2D(idx_t size_in_slots, idx_t bits_per_slot)

   : _bits_per_slot(bits_per_slot)

   , _map(size_in_slots * bits_per_slot)

 {

 }