/* * 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(ASSEMBLER) namespace JSC { size_t ExecutableAllocator::pageSize = 0; #if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND) void ExecutableAllocator::intializePageSize() { #if OS(SYMBIAN) && CPU(ARMV5_OR_LOWER) // The moving memory model (as used in ARMv5 and earlier platforms) // on Symbian OS limits the number of chunks for each process to 16. // To mitigate this limitation increase the pagesize to allocate // fewer, larger chunks. Set the page size to 256 Kb to compensate // for moving memory model limitation 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(); // 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)