diff options
Diffstat (limited to 'src/3rdparty/masm/wtf/PageAllocationAligned.cpp')
-rw-r--r-- | src/3rdparty/masm/wtf/PageAllocationAligned.cpp | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/src/3rdparty/masm/wtf/PageAllocationAligned.cpp b/src/3rdparty/masm/wtf/PageAllocationAligned.cpp new file mode 100644 index 0000000000..bdb976b1b7 --- /dev/null +++ b/src/3rdparty/masm/wtf/PageAllocationAligned.cpp @@ -0,0 +1,85 @@ +/* + * 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. + */ + +#include "config.h" +#include "PageAllocationAligned.h" + +namespace WTF { + +PageAllocationAligned PageAllocationAligned::allocate(size_t size, size_t alignment, OSAllocator::Usage usage, bool writable) +{ + ASSERT(isPageAligned(size)); + ASSERT(isPageAligned(alignment)); + ASSERT(isPowerOfTwo(alignment)); + ASSERT(size >= alignment); + size_t alignmentMask = alignment - 1; + +#if OS(DARWIN) + int flags = VM_FLAGS_ANYWHERE; + if (usage != OSAllocator::UnknownUsage) + flags |= usage; + int protection = PROT_READ; + if (writable) + protection |= PROT_WRITE; + + vm_address_t address = 0; + vm_map(current_task(), &address, size, alignmentMask, flags, MEMORY_OBJECT_NULL, 0, FALSE, protection, PROT_READ | PROT_WRITE, VM_INHERIT_DEFAULT); + return PageAllocationAligned(reinterpret_cast<void*>(address), size); +#else + size_t alignmentDelta = alignment - pageSize(); + + // Resererve with suffcient additional VM to correctly align. + size_t reservationSize = size + alignmentDelta; + void* reservationBase = OSAllocator::reserveUncommitted(reservationSize, usage, writable, false); + + // Select an aligned region within the reservation and commit. + void* alignedBase = reinterpret_cast<uintptr_t>(reservationBase) & alignmentMask + ? reinterpret_cast<void*>((reinterpret_cast<uintptr_t>(reservationBase) & ~alignmentMask) + alignment) + : reservationBase; + OSAllocator::commit(alignedBase, size, writable, false); + + return PageAllocationAligned(alignedBase, size, reservationBase, reservationSize); +#endif +} + +void PageAllocationAligned::deallocate() +{ + // Clear base & size before calling release; if this is *inside* allocation + // then we won't be able to clear then after deallocating the memory. + PageAllocationAligned tmp; + std::swap(tmp, *this); + + ASSERT(tmp); + ASSERT(!*this); + +#if OS(DARWIN) + vm_deallocate(current_task(), reinterpret_cast<vm_address_t>(tmp.base()), tmp.size()); +#else + ASSERT(tmp.m_reservation.contains(tmp.base(), tmp.size())); + OSAllocator::decommitAndRelease(tmp.m_reservation.base(), tmp.m_reservation.size(), tmp.base(), tmp.size()); +#endif +} + +} // namespace WTF |