/*
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "wtf/BitVector.h"

#include "wtf/LeakAnnotations.h"
#include "wtf/PrintStream.h"
#include "wtf/allocator/PartitionAlloc.h"
#include "wtf/allocator/Partitions.h"
#include <algorithm>
#include <string.h>

namespace WTF {

void BitVector::setSlow(const BitVector& other) {
  uintptr_t newBitsOrPointer;
  if (other.isInline()) {
    newBitsOrPointer = other.m_bitsOrPointer;
  } else {
    OutOfLineBits* newOutOfLineBits = OutOfLineBits::create(other.size());
    memcpy(newOutOfLineBits->bits(), other.bits(), byteCount(other.size()));
    newBitsOrPointer = bitwiseCast<uintptr_t>(newOutOfLineBits) >> 1;
  }
  if (!isInline())
    OutOfLineBits::destroy(outOfLineBits());
  m_bitsOrPointer = newBitsOrPointer;
}

void BitVector::resize(size_t numBits) {
  if (numBits <= maxInlineBits()) {
    if (isInline())
      return;

    OutOfLineBits* myOutOfLineBits = outOfLineBits();
    m_bitsOrPointer = makeInlineBits(*myOutOfLineBits->bits());
    OutOfLineBits::destroy(myOutOfLineBits);
    return;
  }

  resizeOutOfLine(numBits);
}

void BitVector::clearAll() {
  if (isInline())
    m_bitsOrPointer = makeInlineBits(0);
  else
    memset(outOfLineBits()->bits(), 0, byteCount(size()));
}

BitVector::OutOfLineBits* BitVector::OutOfLineBits::create(size_t numBits) {
  // Because of the way BitVector stores the pointer, memory tools
  // will erroneously report a leak here.
  WTF_INTERNAL_LEAK_SANITIZER_DISABLED_SCOPE;
  numBits = (numBits + bitsInPointer() - 1) &
            ~(bitsInPointer() - static_cast<size_t>(1));
  size_t size =
      sizeof(OutOfLineBits) + sizeof(uintptr_t) * (numBits / bitsInPointer());
  void* allocation = Partitions::bufferMalloc(
      size, WTF_HEAP_PROFILER_TYPE_NAME(OutOfLineBits));
  OutOfLineBits* result = new (NotNull, allocation) OutOfLineBits(numBits);
  return result;
}

void BitVector::OutOfLineBits::destroy(OutOfLineBits* outOfLineBits) {
  Partitions::bufferFree(outOfLineBits);
}

void BitVector::resizeOutOfLine(size_t numBits) {
  ASSERT(numBits > maxInlineBits());
  OutOfLineBits* newOutOfLineBits = OutOfLineBits::create(numBits);
  size_t newNumWords = newOutOfLineBits->numWords();
  if (isInline()) {
    // Make sure that all of the bits are zero in case we do a no-op resize.
    *newOutOfLineBits->bits() =
        m_bitsOrPointer & ~(static_cast<uintptr_t>(1) << maxInlineBits());
    memset(newOutOfLineBits->bits() + 1, 0, (newNumWords - 1) * sizeof(void*));
  } else {
    if (numBits > size()) {
      size_t oldNumWords = outOfLineBits()->numWords();
      memcpy(newOutOfLineBits->bits(), outOfLineBits()->bits(),
             oldNumWords * sizeof(void*));
      memset(newOutOfLineBits->bits() + oldNumWords, 0,
             (newNumWords - oldNumWords) * sizeof(void*));
    } else {
      memcpy(newOutOfLineBits->bits(), outOfLineBits()->bits(),
             newOutOfLineBits->numWords() * sizeof(void*));
    }
    OutOfLineBits::destroy(outOfLineBits());
  }
  m_bitsOrPointer = bitwiseCast<uintptr_t>(newOutOfLineBits) >> 1;
}

void BitVector::dump(PrintStream& out) {
  for (size_t i = 0; i < size(); ++i) {
    if (get(i))
      out.printf("1");
    else
      out.printf("-");
  }
}

}  // namespace WTF