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/*
* Copyright (C) 2008 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 "config.h"
#include "ExecutableAllocator.h"
#if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
#include "CodeProfiling.h"
#include <wtf/MetaAllocator.h>
#include <wtf/PageReservation.h>
#include <wtf/VMTags.h>
#endif
#if ENABLE(ASSEMBLER)
using namespace WTF;
namespace JSC {
#if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
class DemandExecutableAllocator : public MetaAllocator {
public:
DemandExecutableAllocator()
: MetaAllocator(32) // round up all allocations to 32 bytes
{
// Don't preallocate any memory here.
}
virtual ~DemandExecutableAllocator()
{
for (unsigned i = 0; i < reservations.size(); ++i)
reservations.at(i).deallocate();
}
protected:
virtual void* allocateNewSpace(size_t& numPages)
{
size_t newNumPages = (((numPages * pageSize() + JIT_ALLOCATOR_LARGE_ALLOC_SIZE - 1) / JIT_ALLOCATOR_LARGE_ALLOC_SIZE * JIT_ALLOCATOR_LARGE_ALLOC_SIZE) + pageSize() - 1) / pageSize();
ASSERT(newNumPages >= numPages);
numPages = newNumPages;
PageReservation reservation = PageReservation::reserve(numPages * pageSize(), OSAllocator::JSJITCodePages, EXECUTABLE_POOL_WRITABLE, true);
if (!reservation)
CRASH();
reservations.append(reservation);
return reservation.base();
}
virtual void notifyNeedPage(void* page)
{
OSAllocator::commit(page, pageSize(), EXECUTABLE_POOL_WRITABLE, true);
}
virtual void notifyPageIsFree(void* page)
{
OSAllocator::decommit(page, pageSize());
}
private:
Vector<PageReservation, 16> reservations;
};
static DemandExecutableAllocator* allocator;
void ExecutableAllocator::initializeAllocator()
{
ASSERT(!allocator);
allocator = new DemandExecutableAllocator();
CodeProfiling::notifyAllocator(allocator);
}
ExecutableAllocator::ExecutableAllocator(JSGlobalData&)
{
ASSERT(allocator);
}
bool ExecutableAllocator::isValid() const
{
return true;
}
bool ExecutableAllocator::underMemoryPressure()
{
return false;
}
PassRefPtr<ExecutableMemoryHandle> ExecutableAllocator::allocate(JSGlobalData&, size_t sizeInBytes, void* ownerUID)
{
RefPtr<ExecutableMemoryHandle> result = allocator->allocate(sizeInBytes, ownerUID);
if (!result)
CRASH();
return result.release();
}
size_t ExecutableAllocator::committedByteCount()
{
return allocator->bytesCommitted();
}
#if ENABLE(META_ALLOCATOR_PROFILE)
void ExecutableAllocator::dumpProfile()
{
allocator->dumpProfile();
}
#endif
#endif // ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
#if OS(WINDOWS)
#error "ASSEMBLER_WX_EXCLUSIVE not yet suported on this platform."
#endif
void ExecutableAllocator::reprotectRegion(void* start, size_t size, ProtectionSetting setting)
{
size_t pageSize = WTF::pageSize();
// Calculate the start of the page containing this region,
// and account for this extra memory within size.
intptr_t startPtr = reinterpret_cast<intptr_t>(start);
intptr_t pageStartPtr = startPtr & ~(pageSize - 1);
void* pageStart = reinterpret_cast<void*>(pageStartPtr);
size += (startPtr - pageStartPtr);
// Round size up
size += (pageSize - 1);
size &= ~(pageSize - 1);
mprotect(pageStart, size, (setting == Writable) ? PROTECTION_FLAGS_RW : PROTECTION_FLAGS_RX);
}
#endif
#if CPU(ARM_TRADITIONAL) && OS(LINUX) && COMPILER(RVCT)
__asm void ExecutableAllocator::cacheFlush(void* code, size_t size)
{
ARM
push {r7}
add r1, r1, r0
mov r7, #0xf0000
add r7, r7, #0x2
mov r2, #0x0
svc #0x0
pop {r7}
bx lr
}
#endif
}
#endif // HAVE(ASSEMBLER)
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