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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.
*/
#ifndef ExecutableAllocator_h
#define ExecutableAllocator_h
#include <stddef.h> // for ptrdiff_t
#include <limits>
#include <wtf/Assertions.h>
#include <wtf/PageAllocation.h>
#include <wtf/PassRefPtr.h>
#include <wtf/RefCounted.h>
#include <wtf/UnusedParam.h>
#include <wtf/Vector.h>
#if OS(IOS)
#include <libkern/OSCacheControl.h>
#include <sys/mman.h>
#endif
#if OS(SYMBIAN)
#include <e32std.h>
#endif
#if CPU(MIPS) && OS(LINUX)
#include <sys/cachectl.h>
#endif
#if CPU(SH4) && OS(LINUX)
#include <asm/cachectl.h>
#include <asm/unistd.h>
#include <sys/syscall.h>
#include <unistd.h>
#endif
#if OS(WINCE)
// From pkfuncs.h (private header file from the Platform Builder)
#define CACHE_SYNC_ALL 0x07F
extern "C" __declspec(dllimport) void CacheRangeFlush(LPVOID pAddr, DWORD dwLength, DWORD dwFlags);
#endif
#if PLATFORM(BREWMP)
#include <AEEIMemCache1.h>
#include <AEEMemCache1.bid>
#include <wtf/brew/RefPtrBrew.h>
#endif
#define JIT_ALLOCATOR_LARGE_ALLOC_SIZE (pageSize() * 4)
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
#define PROTECTION_FLAGS_RW (PROT_READ | PROT_WRITE)
#define PROTECTION_FLAGS_RX (PROT_READ | PROT_EXEC)
#define EXECUTABLE_POOL_WRITABLE false
#else
#define EXECUTABLE_POOL_WRITABLE true
#endif
namespace JSC {
class JSGlobalData;
void releaseExecutableMemory(JSGlobalData&);
inline size_t roundUpAllocationSize(size_t request, size_t granularity)
{
if ((std::numeric_limits<size_t>::max() - granularity) <= request)
CRASH(); // Allocation is too large
// Round up to next page boundary
size_t size = request + (granularity - 1);
size = size & ~(granularity - 1);
ASSERT(size >= request);
return size;
}
}
#if ENABLE(JIT) && ENABLE(ASSEMBLER)
namespace JSC {
class ExecutablePool : public RefCounted<ExecutablePool> {
public:
#if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
typedef PageAllocation Allocation;
#else
class Allocation {
public:
Allocation(void* base, size_t size)
: m_base(base)
, m_size(size)
{
}
void* base() { return m_base; }
size_t size() { return m_size; }
bool operator!() const { return !m_base; }
private:
void* m_base;
size_t m_size;
};
#endif
typedef Vector<Allocation, 2> AllocationList;
static PassRefPtr<ExecutablePool> create(JSGlobalData& globalData, size_t n)
{
return adoptRef(new ExecutablePool(globalData, n));
}
void* alloc(JSGlobalData& globalData, size_t n)
{
ASSERT(m_freePtr <= m_end);
// Round 'n' up to a multiple of word size; if all allocations are of
// word sized quantities, then all subsequent allocations will be aligned.
n = roundUpAllocationSize(n, sizeof(void*));
if (static_cast<ptrdiff_t>(n) < (m_end - m_freePtr)) {
void* result = m_freePtr;
m_freePtr += n;
return result;
}
// Insufficient space to allocate in the existing pool
// so we need allocate into a new pool
return poolAllocate(globalData, n);
}
void tryShrink(void* allocation, size_t oldSize, size_t newSize)
{
if (static_cast<char*>(allocation) + oldSize != m_freePtr)
return;
m_freePtr = static_cast<char*>(allocation) + roundUpAllocationSize(newSize, sizeof(void*));
}
~ExecutablePool()
{
AllocationList::iterator end = m_pools.end();
for (AllocationList::iterator ptr = m_pools.begin(); ptr != end; ++ptr)
ExecutablePool::systemRelease(*ptr);
}
size_t available() const { return (m_pools.size() > 1) ? 0 : m_end - m_freePtr; }
private:
static Allocation systemAlloc(size_t n);
static void systemRelease(Allocation& alloc);
ExecutablePool(JSGlobalData&, size_t n);
void* poolAllocate(JSGlobalData&, size_t n);
char* m_freePtr;
char* m_end;
AllocationList m_pools;
};
class ExecutableAllocator {
enum ProtectionSetting { Writable, Executable };
public:
ExecutableAllocator(JSGlobalData& globalData)
{
if (isValid())
m_smallAllocationPool = ExecutablePool::create(globalData, JIT_ALLOCATOR_LARGE_ALLOC_SIZE);
#if !ENABLE(INTERPRETER)
else
CRASH();
#endif
}
bool isValid() const;
static bool underMemoryPressure();
PassRefPtr<ExecutablePool> poolForSize(JSGlobalData& globalData, size_t n)
{
// Try to fit in the existing small allocator
ASSERT(m_smallAllocationPool);
if (n < m_smallAllocationPool->available())
return m_smallAllocationPool;
// If the request is large, we just provide a unshared allocator
if (n > JIT_ALLOCATOR_LARGE_ALLOC_SIZE)
return ExecutablePool::create(globalData, n);
// Create a new allocator
RefPtr<ExecutablePool> pool = ExecutablePool::create(globalData, JIT_ALLOCATOR_LARGE_ALLOC_SIZE);
// If the new allocator will result in more free space than in
// the current small allocator, then we will use it instead
if ((pool->available() - n) > m_smallAllocationPool->available())
m_smallAllocationPool = pool;
return pool.release();
}
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
static void makeWritable(void* start, size_t size)
{
reprotectRegion(start, size, Writable);
}
static void makeExecutable(void* start, size_t size)
{
reprotectRegion(start, size, Executable);
}
#else
static void makeWritable(void*, size_t) {}
static void makeExecutable(void*, size_t) {}
#endif
#if CPU(X86) || CPU(X86_64)
static void cacheFlush(void*, size_t)
{
}
#elif CPU(MIPS)
static void cacheFlush(void* code, size_t size)
{
#if GCC_VERSION_AT_LEAST(4, 3, 0)
#if WTF_MIPS_ISA_REV(2) && !GCC_VERSION_AT_LEAST(4, 4, 3)
int lineSize;
asm("rdhwr %0, $1" : "=r" (lineSize));
//
// Modify "start" and "end" to avoid GCC 4.3.0-4.4.2 bug in
// mips_expand_synci_loop that may execute synci one more time.
// "start" points to the fisrt byte of the cache line.
// "end" points to the last byte of the line before the last cache line.
// Because size is always a multiple of 4, this is safe to set
// "end" to the last byte.
//
intptr_t start = reinterpret_cast<intptr_t>(code) & (-lineSize);
intptr_t end = ((reinterpret_cast<intptr_t>(code) + size - 1) & (-lineSize)) - 1;
__builtin___clear_cache(reinterpret_cast<char*>(start), reinterpret_cast<char*>(end));
#else
intptr_t end = reinterpret_cast<intptr_t>(code) + size;
__builtin___clear_cache(reinterpret_cast<char*>(code), reinterpret_cast<char*>(end));
#endif
#else
_flush_cache(reinterpret_cast<char*>(code), size, BCACHE);
#endif
}
#elif CPU(ARM_THUMB2) && OS(IOS)
static void cacheFlush(void* code, size_t size)
{
sys_cache_control(kCacheFunctionPrepareForExecution, code, size);
}
#elif CPU(ARM_THUMB2) && OS(LINUX)
static void cacheFlush(void* code, size_t size)
{
asm volatile (
"push {r7}\n"
"mov r0, %0\n"
"mov r1, %1\n"
"movw r7, #0x2\n"
"movt r7, #0xf\n"
"movs r2, #0x0\n"
"svc 0x0\n"
"pop {r7}\n"
:
: "r" (code), "r" (reinterpret_cast<char*>(code) + size)
: "r0", "r1", "r2");
}
#elif OS(SYMBIAN)
static void cacheFlush(void* code, size_t size)
{
User::IMB_Range(code, static_cast<char*>(code) + size);
}
#elif CPU(ARM_TRADITIONAL) && OS(LINUX) && COMPILER(RVCT)
static __asm void cacheFlush(void* code, size_t size);
#elif CPU(ARM_TRADITIONAL) && OS(LINUX) && COMPILER(GCC)
static void cacheFlush(void* code, size_t size)
{
asm volatile (
"push {r7}\n"
"mov r0, %0\n"
"mov r1, %1\n"
"mov r7, #0xf0000\n"
"add r7, r7, #0x2\n"
"mov r2, #0x0\n"
"svc 0x0\n"
"pop {r7}\n"
:
: "r" (code), "r" (reinterpret_cast<char*>(code) + size)
: "r0", "r1", "r2");
}
#elif OS(WINCE)
static void cacheFlush(void* code, size_t size)
{
CacheRangeFlush(code, size, CACHE_SYNC_ALL);
}
#elif PLATFORM(BREWMP)
static void cacheFlush(void* code, size_t size)
{
RefPtr<IMemCache1> memCache = createRefPtrInstance<IMemCache1>(AEECLSID_MemCache1);
IMemCache1_ClearCache(memCache.get(), reinterpret_cast<uint32>(code), size, MEMSPACE_CACHE_FLUSH, MEMSPACE_DATACACHE);
IMemCache1_ClearCache(memCache.get(), reinterpret_cast<uint32>(code), size, MEMSPACE_CACHE_INVALIDATE, MEMSPACE_INSTCACHE);
}
#elif CPU(SH4) && OS(LINUX)
static void cacheFlush(void* code, size_t size)
{
#ifdef CACHEFLUSH_D_L2
syscall(__NR_cacheflush, reinterpret_cast<unsigned>(code), size, CACHEFLUSH_D_WB | CACHEFLUSH_I | CACHEFLUSH_D_L2);
#else
syscall(__NR_cacheflush, reinterpret_cast<unsigned>(code), size, CACHEFLUSH_D_WB | CACHEFLUSH_I);
#endif
}
#else
#error "The cacheFlush support is missing on this platform."
#endif
static size_t committedByteCount();
private:
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
static void reprotectRegion(void*, size_t, ProtectionSetting);
#endif
RefPtr<ExecutablePool> m_smallAllocationPool;
};
inline ExecutablePool::ExecutablePool(JSGlobalData& globalData, size_t n)
{
size_t allocSize = roundUpAllocationSize(n, pageSize());
Allocation mem = systemAlloc(allocSize);
if (!mem.base()) {
releaseExecutableMemory(globalData);
mem = systemAlloc(allocSize);
}
m_pools.append(mem);
m_freePtr = static_cast<char*>(mem.base());
if (!m_freePtr)
CRASH(); // Failed to allocate
m_end = m_freePtr + allocSize;
}
inline void* ExecutablePool::poolAllocate(JSGlobalData& globalData, size_t n)
{
size_t allocSize = roundUpAllocationSize(n, pageSize());
Allocation result = systemAlloc(allocSize);
if (!result.base()) {
releaseExecutableMemory(globalData);
result = systemAlloc(allocSize);
if (!result.base())
CRASH(); // Failed to allocate
}
ASSERT(m_end >= m_freePtr);
if ((allocSize - n) > static_cast<size_t>(m_end - m_freePtr)) {
// Replace allocation pool
m_freePtr = static_cast<char*>(result.base()) + n;
m_end = static_cast<char*>(result.base()) + allocSize;
}
m_pools.append(result);
return result.base();
}
}
#endif // ENABLE(JIT) && ENABLE(ASSEMBLER)
#endif // !defined(ExecutableAllocator)
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