jdk8-mips64-public/hotspot: src/share/vm/utilities/bitMap.cpp@faa71d8b8ab5 (annotated)

src/share/vm/utilities/bitMap.cpp@faa71d8b8ab5 (annotated)

src/share/vm/utilities/bitMap.cpp

Tue, 12 Feb 2019 11:58:44 +0100

author: shade
date: Tue, 12 Feb 2019 11:58:44 +0100
changeset 9616: faa71d8b8ab5
parent 6680: 78bbf4d43a14
child 9637: eef07cd490d4
permissions: -rw-r--r--

8211926: Catastrophic size_t underflow in BitMap::*_large methods
Reviewed-by: kbarrett, stuefe

 /*
  * Copyright (c) 1997, 2014, 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.
  *
  */
 #include "precompiled.hpp"
 #include "memory/allocation.inline.hpp"
 #include "utilities/bitMap.inline.hpp"
 #include "utilities/copy.hpp"
 #ifdef TARGET_OS_FAMILY_linux
 # include "os_linux.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_solaris
 # include "os_solaris.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_windows
 # include "os_windows.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_aix
 # include "os_aix.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_bsd
 # include "os_bsd.inline.hpp"
 #endif
 BitMap::BitMap(bm_word_t* map, idx_t size_in_bits) :
   _map(map), _size(size_in_bits), _map_allocator(false)
 {
   assert(sizeof(bm_word_t) == BytesPerWord, "Implementation assumption.");
   assert(size_in_bits >= 0, "just checking");
 }
 BitMap::BitMap(idx_t size_in_bits, bool in_resource_area) :
   _map(NULL), _size(0), _map_allocator(false)
 {
   assert(sizeof(bm_word_t) == BytesPerWord, "Implementation assumption.");
   resize(size_in_bits, in_resource_area);
 }
 void BitMap::resize(idx_t size_in_bits, bool in_resource_area) {
   assert(size_in_bits >= 0, "just checking");
   idx_t old_size_in_words = size_in_words();
   bm_word_t* old_map = map();
   _size = size_in_bits;
   idx_t new_size_in_words = size_in_words();
   if (in_resource_area) {
     _map = NEW_RESOURCE_ARRAY(bm_word_t, new_size_in_words);
   } else {
     if (old_map != NULL) {
       _map_allocator.free();
     }
     _map = _map_allocator.allocate(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());
   }
 }
 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) {
     bm_word_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) {
     bm_word_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  = res;
       nw = value ? (w | ~mr) : (w & mr);
     }
   }
 }
 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);
   }
 }
 bool BitMap::is_small_range_of_words(idx_t beg_full_word, idx_t end_full_word) {
   // There is little point to call large version on small ranges.
   // Need to check carefully, keeping potential idx_t underflow in mind.
   // The threshold should be at least one word.
   STATIC_ASSERT(small_range_words >= 1);
   return (beg_full_word + small_range_words >= end_full_word);
 }
 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);
   if (is_small_range_of_words(beg_full_word, end_full_word)) {
     set_range(beg, end);
     return;
   }
   // 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);
   if (is_small_range_of_words(beg_full_word, end_full_word)) {
     clear_range(beg, end);
     return;
   }
   // 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);
   if (is_small_range_of_words(beg_full_word, end_full_word)) {
     par_at_put_range(beg, end, value);
     return;
   }
   // 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");
   bm_word_t* dest_map = map();
   bm_word_t* other_map = other.map();
   idx_t size = size_in_words();
   for (idx_t index = 0; index < size_in_words(); index++) {
     bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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];
   }
 }
 void BitMap::set_intersection_at_offset(BitMap other, idx_t offset) {
   assert(other.size() >= offset, "offset not in range");
   assert(other.size() - offset >= size(), "other not large enough");
   // XXX Ideally, we would remove this restriction.
   guarantee((offset % (sizeof(bm_word_t) * BitsPerByte)) == 0,
             "Only handle aligned cases so far.");
   bm_word_t* dest_map = map();
   bm_word_t* other_map = other.map();
   idx_t offset_word_ind = word_index(offset);
   idx_t size = size_in_words();
   for (idx_t index = 0; index < size; index++) {
     dest_map[index] = dest_map[index] & other_map[offset_word_ind + index];
   }
 }
 bool BitMap::set_union_with_result(BitMap other) {
   assert(size() == other.size(), "must have same size");
   bool changed = false;
   bm_word_t* dest_map = map();
   bm_word_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;
   bm_word_t* dest_map = map();
   bm_word_t* other_map = other.map();
   idx_t size = size_in_words();
   for (idx_t index = 0; index < size; index++) {
     bm_word_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;
   bm_word_t* dest_map = map();
   bm_word_t* other_map = other.map();
   idx_t size = size_in_words();
   for (idx_t index = 0; index < size; index++) {
     bm_word_t orig = dest_map[index];
     bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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");
   bm_word_t* dest_map = map();
   bm_word_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 {
   bm_word_t* word = map();
   idx_t rest = size();
   for (; rest >= (idx_t) BitsPerWord; rest -= BitsPerWord) {
     if (*word != (bm_word_t) AllBits) return false;
     word++;
   }
   return rest == 0 || (*word | ~right_n_bits((int)rest)) == (bm_word_t) AllBits;
 }
 bool BitMap::is_empty() const {
   bm_word_t* word = map();
   idx_t rest = size();
   for (; rest >= (idx_t) BitsPerWord; rest -= BitsPerWord) {
     if (*word != (bm_word_t) NoBits) return false;
     word++;
   }
   return rest == 0 || (*word & right_n_bits((int)rest)) == (bm_word_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.
 bool 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 != (bm_word_t)NoBits; offset++) {
       if (rest & 1) {
         if (!blk->do_bit(offset)) return false;
         //  resample at each closure application
         // (see, for instance, CMS bug 4525989)
         rest = map(index) >> (offset & (BitsPerWord -1));
       }
       rest = rest >> 1;
     }
   }
   return true;
 }
 BitMap::idx_t* BitMap::_pop_count_table = NULL;
 void BitMap::init_pop_count_table() {
   if (_pop_count_table == NULL) {
     BitMap::idx_t *table = NEW_C_HEAP_ARRAY(idx_t, 256, mtInternal);
     for (uint i = 0; i < 256; i++) {
       table[i] = num_set_bits(i);
     }
     intptr_t res = Atomic::cmpxchg_ptr((intptr_t)  table,
                                        (intptr_t*) &_pop_count_table,
                                        (intptr_t)  NULL_WORD);
     if (res != NULL_WORD) {
       guarantee( _pop_count_table == (void*) res, "invariant" );
       FREE_C_HEAP_ARRAY(bm_word_t, table, mtInternal);
     }
   }
 }
 BitMap::idx_t BitMap::num_set_bits(bm_word_t w) {
   idx_t bits = 0;
   while (w != 0) {
     while ((w & 1) == 0) {
       w >>= 1;
     }
     bits++;
     w >>= 1;
   }
   return bits;
 }
 BitMap::idx_t BitMap::num_set_bits_from_table(unsigned char c) {
   assert(_pop_count_table != NULL, "precondition");
   return _pop_count_table[c];
 }
 BitMap::idx_t BitMap::count_one_bits() const {
   init_pop_count_table(); // If necessary.
   idx_t sum = 0;
   typedef unsigned char uchar;
   for (idx_t i = 0; i < size_in_words(); i++) {
     bm_word_t w = map()[i];
     for (size_t j = 0; j < sizeof(bm_word_t); j++) {
       sum += num_set_bits_from_table(uchar(w & 255));
       w >>= 8;
     }
   }
   return sum;
 }
 void BitMap::print_on_error(outputStream* st, const char* prefix) const {
   st->print_cr("%s[" PTR_FORMAT ", " PTR_FORMAT ")",
       prefix, p2i(map()), p2i((char*)map() + (size() >> LogBitsPerByte)));
 }
 #ifndef PRODUCT
 void BitMap::print_on(outputStream* st) const {
   tty->print("Bitmap(" SIZE_FORMAT "):", size());
   for (idx_t index = 0; index < size(); index++) {
     tty->print("%c", at(index) ? '1' : '0');
   }
   tty->cr();
 }
 #endif
 BitMap2D::BitMap2D(bm_word_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)
 {
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/utilities/bitMap.cpp@faa71d8b8ab5 (annotated)

src/share/vm/utilities/bitMap.cpp