src/share/vm/utilities/bitMap.inline.hpp

Thu, 27 Jan 2011 16:11:27 -0800

author
coleenp
date
Thu, 27 Jan 2011 16:11:27 -0800
changeset 2497
3582bf76420e
parent 2314
f95d63e2154a
child 3454
2e966d967c5c
permissions
-rw-r--r--

6990754: Use native memory and reference counting to implement SymbolTable
Summary: move symbols from permgen into C heap and reference count them
Reviewed-by: never, acorn, jmasa, stefank

     1 /*
     2  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #ifndef SHARE_VM_UTILITIES_BITMAP_INLINE_HPP
    26 #define SHARE_VM_UTILITIES_BITMAP_INLINE_HPP
    28 #include "runtime/atomic.hpp"
    29 #include "utilities/bitMap.hpp"
    31 #ifdef ASSERT
    32 inline void BitMap::verify_index(idx_t index) const {
    33   assert(index < _size, "BitMap index out of bounds");
    34 }
    36 inline void BitMap::verify_range(idx_t beg_index, idx_t end_index) const {
    37   assert(beg_index <= end_index, "BitMap range error");
    38   // Note that [0,0) and [size,size) are both valid ranges.
    39   if (end_index != _size) verify_index(end_index);
    40 }
    41 #endif // #ifdef ASSERT
    43 inline void BitMap::set_bit(idx_t bit) {
    44   verify_index(bit);
    45   *word_addr(bit) |= bit_mask(bit);
    46 }
    48 inline void BitMap::clear_bit(idx_t bit) {
    49   verify_index(bit);
    50   *word_addr(bit) &= ~bit_mask(bit);
    51 }
    53 inline bool BitMap::par_set_bit(idx_t bit) {
    54   verify_index(bit);
    55   volatile idx_t* const addr = word_addr(bit);
    56   const idx_t mask = bit_mask(bit);
    57   idx_t old_val = *addr;
    59   do {
    60     const idx_t new_val = old_val | mask;
    61     if (new_val == old_val) {
    62       return false;     // Someone else beat us to it.
    63     }
    64     const idx_t cur_val = (idx_t) Atomic::cmpxchg_ptr((void*) new_val,
    65                                                       (volatile void*) addr,
    66                                                       (void*) old_val);
    67     if (cur_val == old_val) {
    68       return true;      // Success.
    69     }
    70     old_val = cur_val;  // The value changed, try again.
    71   } while (true);
    72 }
    74 inline bool BitMap::par_clear_bit(idx_t bit) {
    75   verify_index(bit);
    76   volatile idx_t* const addr = word_addr(bit);
    77   const idx_t mask = ~bit_mask(bit);
    78   idx_t old_val = *addr;
    80   do {
    81     const idx_t new_val = old_val & mask;
    82     if (new_val == old_val) {
    83       return false;     // Someone else beat us to it.
    84     }
    85     const idx_t cur_val = (idx_t) Atomic::cmpxchg_ptr((void*) new_val,
    86                                                       (volatile void*) addr,
    87                                                       (void*) old_val);
    88     if (cur_val == old_val) {
    89       return true;      // Success.
    90     }
    91     old_val = cur_val;  // The value changed, try again.
    92   } while (true);
    93 }
    95 inline void BitMap::set_range(idx_t beg, idx_t end, RangeSizeHint hint) {
    96   if (hint == small_range && end - beg == 1) {
    97     set_bit(beg);
    98   } else {
    99     if (hint == large_range) {
   100       set_large_range(beg, end);
   101     } else {
   102       set_range(beg, end);
   103     }
   104   }
   105 }
   107 inline void BitMap::clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {
   108   if (hint == small_range && end - beg == 1) {
   109     clear_bit(beg);
   110   } else {
   111     if (hint == large_range) {
   112       clear_large_range(beg, end);
   113     } else {
   114       clear_range(beg, end);
   115     }
   116   }
   117 }
   119 inline void BitMap::par_set_range(idx_t beg, idx_t end, RangeSizeHint hint) {
   120   if (hint == small_range && end - beg == 1) {
   121     par_at_put(beg, true);
   122   } else {
   123     if (hint == large_range) {
   124       par_at_put_large_range(beg, end, true);
   125     } else {
   126       par_at_put_range(beg, end, true);
   127     }
   128   }
   129 }
   131 inline void BitMap::set_range_of_words(idx_t beg, idx_t end) {
   132   bm_word_t* map = _map;
   133   for (idx_t i = beg; i < end; ++i) map[i] = ~(uintptr_t)0;
   134 }
   137 inline void BitMap::clear_range_of_words(idx_t beg, idx_t end) {
   138   bm_word_t* map = _map;
   139   for (idx_t i = beg; i < end; ++i) map[i] = 0;
   140 }
   143 inline void BitMap::clear() {
   144   clear_range_of_words(0, size_in_words());
   145 }
   148 inline void BitMap::par_clear_range(idx_t beg, idx_t end, RangeSizeHint hint) {
   149   if (hint == small_range && end - beg == 1) {
   150     par_at_put(beg, false);
   151   } else {
   152     if (hint == large_range) {
   153       par_at_put_large_range(beg, end, false);
   154     } else {
   155       par_at_put_range(beg, end, false);
   156     }
   157   }
   158 }
   160 inline BitMap::idx_t
   161 BitMap::get_next_one_offset_inline(idx_t l_offset, idx_t r_offset) const {
   162   assert(l_offset <= size(), "BitMap index out of bounds");
   163   assert(r_offset <= size(), "BitMap index out of bounds");
   164   assert(l_offset <= r_offset, "l_offset > r_offset ?");
   166   if (l_offset == r_offset) {
   167     return l_offset;
   168   }
   169   idx_t   index = word_index(l_offset);
   170   idx_t r_index = word_index(r_offset-1) + 1;
   171   idx_t res_offset = l_offset;
   173   // check bits including and to the _left_ of offset's position
   174   idx_t pos = bit_in_word(res_offset);
   175   idx_t res = map(index) >> pos;
   176   if (res != (uintptr_t)NoBits) {
   177     // find the position of the 1-bit
   178     for (; !(res & 1); res_offset++) {
   179       res = res >> 1;
   180     }
   181     assert(res_offset >= l_offset &&
   182            res_offset < r_offset, "just checking");
   183     return MIN2(res_offset, r_offset);
   184   }
   185   // skip over all word length 0-bit runs
   186   for (index++; index < r_index; index++) {
   187     res = map(index);
   188     if (res != (uintptr_t)NoBits) {
   189       // found a 1, return the offset
   190       for (res_offset = bit_index(index); !(res & 1); res_offset++) {
   191         res = res >> 1;
   192       }
   193       assert(res & 1, "tautology; see loop condition");
   194       assert(res_offset >= l_offset, "just checking");
   195       return MIN2(res_offset, r_offset);
   196     }
   197   }
   198   return r_offset;
   199 }
   201 inline BitMap::idx_t
   202 BitMap::get_next_zero_offset_inline(idx_t l_offset, idx_t r_offset) const {
   203   assert(l_offset <= size(), "BitMap index out of bounds");
   204   assert(r_offset <= size(), "BitMap index out of bounds");
   205   assert(l_offset <= r_offset, "l_offset > r_offset ?");
   207   if (l_offset == r_offset) {
   208     return l_offset;
   209   }
   210   idx_t   index = word_index(l_offset);
   211   idx_t r_index = word_index(r_offset-1) + 1;
   212   idx_t res_offset = l_offset;
   214   // check bits including and to the _left_ of offset's position
   215   idx_t pos = res_offset & (BitsPerWord - 1);
   216   idx_t res = (map(index) >> pos) | left_n_bits((int)pos);
   218   if (res != (uintptr_t)AllBits) {
   219     // find the position of the 0-bit
   220     for (; res & 1; res_offset++) {
   221       res = res >> 1;
   222     }
   223     assert(res_offset >= l_offset, "just checking");
   224     return MIN2(res_offset, r_offset);
   225   }
   226   // skip over all word length 1-bit runs
   227   for (index++; index < r_index; index++) {
   228     res = map(index);
   229     if (res != (uintptr_t)AllBits) {
   230       // found a 0, return the offset
   231       for (res_offset = index << LogBitsPerWord; res & 1;
   232            res_offset++) {
   233         res = res >> 1;
   234       }
   235       assert(!(res & 1), "tautology; see loop condition");
   236       assert(res_offset >= l_offset, "just checking");
   237       return MIN2(res_offset, r_offset);
   238     }
   239   }
   240   return r_offset;
   241 }
   243 inline BitMap::idx_t
   244 BitMap::get_next_one_offset_inline_aligned_right(idx_t l_offset,
   245                                                  idx_t r_offset) const
   246 {
   247   verify_range(l_offset, r_offset);
   248   assert(bit_in_word(r_offset) == 0, "r_offset not word-aligned");
   250   if (l_offset == r_offset) {
   251     return l_offset;
   252   }
   253   idx_t   index = word_index(l_offset);
   254   idx_t r_index = word_index(r_offset);
   255   idx_t res_offset = l_offset;
   257   // check bits including and to the _left_ of offset's position
   258   idx_t res = map(index) >> bit_in_word(res_offset);
   259   if (res != (uintptr_t)NoBits) {
   260     // find the position of the 1-bit
   261     for (; !(res & 1); res_offset++) {
   262       res = res >> 1;
   263     }
   264     assert(res_offset >= l_offset &&
   265            res_offset < r_offset, "just checking");
   266     return res_offset;
   267   }
   268   // skip over all word length 0-bit runs
   269   for (index++; index < r_index; index++) {
   270     res = map(index);
   271     if (res != (uintptr_t)NoBits) {
   272       // found a 1, return the offset
   273       for (res_offset = bit_index(index); !(res & 1); res_offset++) {
   274         res = res >> 1;
   275       }
   276       assert(res & 1, "tautology; see loop condition");
   277       assert(res_offset >= l_offset && res_offset < r_offset, "just checking");
   278       return res_offset;
   279     }
   280   }
   281   return r_offset;
   282 }
   285 // Returns a bit mask for a range of bits [beg, end) within a single word.  Each
   286 // bit in the mask is 0 if the bit is in the range, 1 if not in the range.  The
   287 // returned mask can be used directly to clear the range, or inverted to set the
   288 // range.  Note:  end must not be 0.
   289 inline BitMap::bm_word_t
   290 BitMap::inverted_bit_mask_for_range(idx_t beg, idx_t end) const {
   291   assert(end != 0, "does not work when end == 0");
   292   assert(beg == end || word_index(beg) == word_index(end - 1),
   293          "must be a single-word range");
   294   bm_word_t mask = bit_mask(beg) - 1;   // low (right) bits
   295   if (bit_in_word(end) != 0) {
   296     mask |= ~(bit_mask(end) - 1);       // high (left) bits
   297   }
   298   return mask;
   299 }
   301 inline void BitMap::set_large_range_of_words(idx_t beg, idx_t end) {
   302   memset(_map + beg, ~(unsigned char)0, (end - beg) * sizeof(uintptr_t));
   303 }
   305 inline void BitMap::clear_large_range_of_words(idx_t beg, idx_t end) {
   306   memset(_map + beg, 0, (end - beg) * sizeof(uintptr_t));
   307 }
   309 inline BitMap::idx_t BitMap::word_index_round_up(idx_t bit) const {
   310   idx_t bit_rounded_up = bit + (BitsPerWord - 1);
   311   // Check for integer arithmetic overflow.
   312   return bit_rounded_up > bit ? word_index(bit_rounded_up) : size_in_words();
   313 }
   315 inline BitMap::idx_t BitMap::get_next_one_offset(idx_t l_offset,
   316                                           idx_t r_offset) const {
   317   return get_next_one_offset_inline(l_offset, r_offset);
   318 }
   320 inline BitMap::idx_t BitMap::get_next_zero_offset(idx_t l_offset,
   321                                            idx_t r_offset) const {
   322   return get_next_zero_offset_inline(l_offset, r_offset);
   323 }
   325 inline void BitMap2D::clear() {
   326   _map.clear();
   327 }
   329 #endif // SHARE_VM_UTILITIES_BITMAP_INLINE_HPP

mercurial