Move Source/WTF/wtf to Source/wtf

Source/WTF/wtf/OSAllocator.h

-/*
- * Copyright (C) 2010 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. AND ITS CONTRIBUTORS ``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 ITS 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.
- */
-
-#ifndef OSAllocator_h
-#define OSAllocator_h
-
-#include <algorithm>
-#include <wtf/UnusedParam.h>
-#include <wtf/VMTags.h>
-
-namespace WTF {
-
-class OSAllocator {
-public:
-    enum Usage {
-        UnknownUsage = -1,
-        FastMallocPages = VM_TAG_FOR_TCMALLOC_MEMORY,
-        JSGCHeapPages = VM_TAG_FOR_COLLECTOR_MEMORY,
-        JSVMStackPages = VM_TAG_FOR_REGISTERFILE_MEMORY,
-        JSJITCodePages = VM_TAG_FOR_EXECUTABLEALLOCATOR_MEMORY,
-    };
-
-    // These methods are symmetric; reserveUncommitted allocates VM in an uncommitted state,
-    // releaseDecommitted should be called on a region of VM allocated by a single reservation,
-    // the memory must all currently be in a decommitted state.
-    static void* reserveUncommitted(size_t, Usage = UnknownUsage, bool writable = true, bool executable = false, bool includesGuardPages = false);
-    WTF_EXPORT_PRIVATE static void releaseDecommitted(void*, size_t);
-
-    // These methods are symmetric; they commit or decommit a region of VM (uncommitted VM should
-    // never be accessed, since the OS may not have attached physical memory for these regions).
-    // Clients should only call commit on uncommitted regions and decommit on committed regions.
-    static void commit(void*, size_t, bool writable, bool executable);
-    static void decommit(void*, size_t);
-
-    // These methods are symmetric; reserveAndCommit allocates VM in an committed state,
-    // decommitAndRelease should be called on a region of VM allocated by a single reservation,
-    // the memory must all currently be in a committed state.
-    WTF_EXPORT_PRIVATE static void* reserveAndCommit(size_t, Usage = UnknownUsage, bool writable = true, bool executable = false, bool includesGuardPages = false);
-    static void decommitAndRelease(void* base, size_t size);
-
-    // These methods are akin to reserveAndCommit/decommitAndRelease, above - however rather than
-    // committing/decommitting the entire region additional parameters allow a subregion to be
-    // specified.
-    static void* reserveAndCommit(size_t reserveSize, size_t commitSize, Usage = UnknownUsage, bool writable = true, bool executable = false);
-    static void decommitAndRelease(void* releaseBase, size_t releaseSize, void* decommitBase, size_t decommitSize);
-
-    // Reallocate an existing, committed allocation.
-    // The prior allocation must be fully comitted, and the new size will also be fully committed.
-    // This interface is provided since it may be possible to optimize this operation on some platforms.
-    template<typename T>
-    static T* reallocateCommitted(T*, size_t oldSize, size_t newSize, Usage = UnknownUsage, bool writable = true, bool executable = false);
-};
-
-inline void* OSAllocator::reserveAndCommit(size_t reserveSize, size_t commitSize, Usage usage, bool writable, bool executable)
-{
-    void* base = reserveUncommitted(reserveSize, usage, writable, executable);
-    commit(base, commitSize, writable, executable);
-    return base;
-}
-
-inline void OSAllocator::decommitAndRelease(void* releaseBase, size_t releaseSize, void* decommitBase, size_t decommitSize)
-{
-    ASSERT(decommitBase >= releaseBase && (static_cast<char*>(decommitBase) + decommitSize) <= (static_cast<char*>(releaseBase) + releaseSize));
-#if OS(WINCE)
-    // On most platforms we can actually skip this final decommit; releasing the VM will
-    // implicitly decommit any physical memory in the region. This is not true on WINCE.
-    decommit(decommitBase, decommitSize);
-#else
-    UNUSED_PARAM(decommitBase);
-    UNUSED_PARAM(decommitSize);
-#endif
-    releaseDecommitted(releaseBase, releaseSize);
-}
-
-inline void OSAllocator::decommitAndRelease(void* base, size_t size)
-{
-    decommitAndRelease(base, size, base, size);
-}
-
-template<typename T>
-inline T* OSAllocator::reallocateCommitted(T* oldBase, size_t oldSize, size_t newSize, Usage usage, bool writable, bool executable)
-{
-    void* newBase = reserveAndCommit(newSize, usage, writable, executable);
-    memcpy(newBase, oldBase, std::min(oldSize, newSize));
-    decommitAndRelease(oldBase, oldSize);
-    return static_cast<T*>(newBase);
-}
-
-} // namespace WTF
-
-using WTF::OSAllocator;
-
-#endif // OSAllocator_h