ExecutableAllocator.cpp [plain text]
#include "config.h"
#include "ExecutableAllocator.h"
#if ENABLE(ASSEMBLER)
namespace JSC {
size_t ExecutableAllocator::pageSize = 0;
#if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
void ExecutableAllocator::intializePageSize()
{
#if OS(SYMBIAN) && CPU(ARMV5_OR_LOWER)
ExecutableAllocator::pageSize = 256 * 1024;
#else
ExecutableAllocator::pageSize = WTF::pageSize();
#endif
}
ExecutablePool::Allocation ExecutablePool::systemAlloc(size_t size)
{
PageAllocation allocation = PageAllocation::allocate(size, OSAllocator::JSJITCodePages, EXECUTABLE_POOL_WRITABLE, true);
if (!allocation)
CRASH();
return allocation;
}
void ExecutablePool::systemRelease(ExecutablePool::Allocation& allocation)
{
allocation.deallocate();
}
bool ExecutableAllocator::isValid() const
{
return true;
}
bool ExecutableAllocator::underMemoryPressure()
{
return false;
}
size_t ExecutableAllocator::committedByteCount()
{
return 0;
}
#endif
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
#if OS(WINDOWS) || OS(SYMBIAN)
#error "ASSEMBLER_WX_EXCLUSIVE not yet suported on this platform."
#endif
void ExecutableAllocator::reprotectRegion(void* start, size_t size, ProtectionSetting setting)
{
if (!pageSize)
intializePageSize();
intptr_t startPtr = reinterpret_cast<intptr_t>(start);
intptr_t pageStartPtr = startPtr & ~(pageSize - 1);
void* pageStart = reinterpret_cast<void*>(pageStartPtr);
size += (startPtr - pageStartPtr);
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)