aoqi@0: /*
aoqi@0:  * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp"
aoqi@0: #include "memory/freeBlockDictionary.hpp"
aoqi@0: #include "utilities/copy.hpp"
aoqi@0: 
aoqi@0: PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: 
aoqi@0: #define baadbabeHeapWord badHeapWordVal
aoqi@0: #define deadbeefHeapWord 0xdeadbeef
aoqi@0: 
aoqi@0: size_t const FreeChunk::header_size() {
aoqi@0:   return sizeof(FreeChunk)/HeapWordSize;
aoqi@0: }
aoqi@0: 
aoqi@0: void FreeChunk::mangleAllocated(size_t size) {
aoqi@0:   // mangle all but the header of a just-allocated block
aoqi@0:   // of storage
aoqi@0:   assert(size >= MinChunkSize, "smallest size of object");
aoqi@0:   // we can't assert that _size == size because this may be an
aoqi@0:   // allocation out of a linear allocation block
aoqi@0:   assert(sizeof(FreeChunk) % HeapWordSize == 0,
aoqi@0:          "shouldn't write beyond chunk");
aoqi@0:   HeapWord* addr = (HeapWord*)this;
aoqi@0:   size_t hdr = header_size();
aoqi@0:   Copy::fill_to_words(addr + hdr, size - hdr, baadbabeHeapWord);
aoqi@0: }
aoqi@0: 
aoqi@0: void FreeChunk::mangleFreed(size_t sz) {
aoqi@0:   assert(baadbabeHeapWord != deadbeefHeapWord, "Need distinct patterns");
aoqi@0:   // mangle all but the header of a just-freed block of storage
aoqi@0:   // just prior to passing it to the storage dictionary
aoqi@0:   assert(sz >= MinChunkSize, "smallest size of object");
aoqi@0:   assert(sz == size(), "just checking");
aoqi@0:   HeapWord* addr = (HeapWord*)this;
aoqi@0:   size_t hdr = header_size();
aoqi@0:   Copy::fill_to_words(addr + hdr, sz - hdr, deadbeefHeapWord);
aoqi@0: }
aoqi@0: 
aoqi@0: void FreeChunk::verifyList() const {
aoqi@0:   FreeChunk* nextFC = next();
aoqi@0:   if (nextFC != NULL) {
aoqi@0:     assert(this == nextFC->prev(), "broken chain");
aoqi@0:     assert(size() == nextFC->size(), "wrong size");
aoqi@0:     nextFC->verifyList();
aoqi@0:   }
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: void FreeChunk::print_on(outputStream* st) {
aoqi@0:   st->print_cr("Next: " PTR_FORMAT " Prev: " PTR_FORMAT " %s",
aoqi@0:     next(), prev(), cantCoalesce() ? "[can't coalesce]" : "");
aoqi@0: }