ftl/FTLDataSection.cpp

   1 /*
   2  * Copyright (C) 2014 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "FTLDataSection.h"
  28
  29 #if ENABLE(FTL_JIT)
  30
  31 #include <wtf/Assertions.h>
  32 #include <wtf/DataLog.h>
  33 #include <wtf/FastMalloc.h>
  34
  35 namespace JSC { namespace FTL {
  36
  37 DataSection::DataSection(size_t size, unsigned alignment)
  38     : m_size(size)
  39 {
  40     RELEASE_ASSERT(WTF::bitCount(alignment) == 1);
  41
  42     const unsigned nativeAlignment = 8;
  43
  44     alignment = std::max(nativeAlignment, alignment);
  45
  46     size_t allocatedSize = size + alignment - nativeAlignment;
  47     m_allocationBase = fastMalloc(allocatedSize);
  48
  49     m_base = bitwise_cast<void*>(
  50         (bitwise_cast<uintptr_t>(m_allocationBase) + alignment - 1) & ~static_cast<uintptr_t>(alignment - 1));
  51
  52     RELEASE_ASSERT(!(bitwise_cast<uintptr_t>(m_base) & (alignment - 1)));
  53     RELEASE_ASSERT(bitwise_cast<uintptr_t>(m_base) + size <= bitwise_cast<uintptr_t>(m_allocationBase) + allocatedSize);
  54 }
  55
  56 DataSection::~DataSection()
  57 {
  58     fastFree(m_allocationBase);
  59 }
  60
  61 } } // namespace JSC::FTL
  62
  63 #endif // ENABLE(FTL_JIT)
  64