hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/freeChunk.cpp
author drchase
Fri, 09 May 2014 16:50:54 -0400
changeset 24424 2658d7834c6e
parent 13963 e5b53c306fb5
child 29797 4d360e3ddebf
permissions -rw-r--r--
8037816: Fix for 8036122 breaks build with Xcode5/clang Summary: Repaired or selectively disabled offending formats; future-proofed with additional checking Reviewed-by: kvn, jrose, stefank

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "gc_implementation/concurrentMarkSweep/freeChunk.hpp"
#include "memory/freeBlockDictionary.hpp"
#include "utilities/copy.hpp"

PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC

#ifndef PRODUCT

#define baadbabeHeapWord badHeapWordVal
#define deadbeefHeapWord 0xdeadbeef

size_t const FreeChunk::header_size() {
  return sizeof(FreeChunk)/HeapWordSize;
}

void FreeChunk::mangleAllocated(size_t size) {
  // mangle all but the header of a just-allocated block
  // of storage
  assert(size >= MinChunkSize, "smallest size of object");
  // we can't assert that _size == size because this may be an
  // allocation out of a linear allocation block
  assert(sizeof(FreeChunk) % HeapWordSize == 0,
         "shouldn't write beyond chunk");
  HeapWord* addr = (HeapWord*)this;
  size_t hdr = header_size();
  Copy::fill_to_words(addr + hdr, size - hdr, baadbabeHeapWord);
}

void FreeChunk::mangleFreed(size_t sz) {
  assert(baadbabeHeapWord != deadbeefHeapWord, "Need distinct patterns");
  // mangle all but the header of a just-freed block of storage
  // just prior to passing it to the storage dictionary
  assert(sz >= MinChunkSize, "smallest size of object");
  assert(sz == size(), "just checking");
  HeapWord* addr = (HeapWord*)this;
  size_t hdr = header_size();
  Copy::fill_to_words(addr + hdr, sz - hdr, deadbeefHeapWord);
}

void FreeChunk::verifyList() const {
  FreeChunk* nextFC = next();
  if (nextFC != NULL) {
    assert(this == nextFC->prev(), "broken chain");
    assert(size() == nextFC->size(), "wrong size");
    nextFC->verifyList();
  }
}
#endif

void FreeChunk::print_on(outputStream* st) {
  st->print_cr("Next: " PTR_FORMAT " Prev: " PTR_FORMAT " %s",
    next(), prev(), cantCoalesce() ? "[can't coalesce]" : "");
}