Mercurial > hg > truffle
view src/share/vm/utilities/bitMap.cpp @ 20256:b0b97602393a
8033923: Use BufferingOopClosure for G1 code root scanning
Reviewed-by: mgerdin, brutisso
author | stefank |
---|---|
date | Mon, 10 Feb 2014 12:58:09 +0100 |
parents | 78bbf4d43a14 |
children | 52b4284cb496 |
line wrap: on
line source
/* * 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); } } 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"); 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) { }