diff -r 000000000000 -r 4f2f89ce4247 JavaScriptCore/jit/ExecutableAllocator.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/jit/ExecutableAllocator.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,328 @@
+/*
+ * 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/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+#include <wtf/UnusedParam.h>
+#include <wtf/Vector.h>
+
+#if OS(IPHONE_OS)
+#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 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
+
+#define JIT_ALLOCATOR_PAGE_SIZE (ExecutableAllocator::pageSize)
+#define JIT_ALLOCATOR_LARGE_ALLOC_SIZE (ExecutableAllocator::pageSize * 4)
+
+#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
+#define PROTECTION_FLAGS_RW (PROT_READ | PROT_WRITE)
+#define PROTECTION_FLAGS_RX (PROT_READ | PROT_EXEC)
+#define INITIAL_PROTECTION_FLAGS PROTECTION_FLAGS_RX
+#else
+#define INITIAL_PROTECTION_FLAGS (PROT_READ | PROT_WRITE | PROT_EXEC)
+#endif
+
+namespace JSC {
+
+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> {
+private:
+    struct Allocation {
+        char* pages;
+        size_t size;
+#if OS(SYMBIAN)
+        RChunk* chunk;
+#endif
+    };
+    typedef Vector<Allocation, 2> AllocationList;
+
+public:
+    static PassRefPtr<ExecutablePool> create(size_t n)
+    {
+        return adoptRef(new ExecutablePool(n));
+    }
+
+    void* alloc(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(n);
+    }
+    
+    ~ExecutablePool()
+    {
+        AllocationList::const_iterator end = m_pools.end();
+        for (AllocationList::const_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(const Allocation& alloc);
+
+    ExecutablePool(size_t n);
+
+    void* poolAllocate(size_t n);
+
+    char* m_freePtr;
+    char* m_end;
+    AllocationList m_pools;
+};
+
+class ExecutableAllocator {
+    enum ProtectionSeting { Writable, Executable };
+
+public:
+    static size_t pageSize;
+    ExecutableAllocator()
+    {
+        if (!pageSize)
+            intializePageSize();
+        if (isValid())
+            m_smallAllocationPool = ExecutablePool::create(JIT_ALLOCATOR_LARGE_ALLOC_SIZE);
+#if !ENABLE(INTERPRETER)
+        else
+            CRASH();
+#endif
+    }
+
+    bool isValid() const;
+    
+    PassRefPtr<ExecutablePool> poolForSize(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(n);
+
+        // Create a new allocator
+        RefPtr<ExecutablePool> pool = ExecutablePool::create(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 COMPILER(GCC) && (GCC_VERSION >= 40300)
+#if WTF_MIPS_ISA_REV(2) && (GCC_VERSION < 40403)
+        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(IPHONE_OS)
+    static void cacheFlush(void* code, size_t size)
+    {
+        sys_dcache_flush(code, size);
+        sys_icache_invalidate(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);
+    }
+#else
+    #error "The cacheFlush support is missing on this platform."
+#endif
+
+private:
+
+#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
+    static void reprotectRegion(void*, size_t, ProtectionSeting);
+#endif
+
+    RefPtr<ExecutablePool> m_smallAllocationPool;
+    static void intializePageSize();
+};
+
+inline ExecutablePool::ExecutablePool(size_t n)
+{
+    size_t allocSize = roundUpAllocationSize(n, JIT_ALLOCATOR_PAGE_SIZE);
+    Allocation mem = systemAlloc(allocSize);
+    m_pools.append(mem);
+    m_freePtr = mem.pages;
+    if (!m_freePtr)
+        CRASH(); // Failed to allocate
+    m_end = m_freePtr + allocSize;
+}
+
+inline void* ExecutablePool::poolAllocate(size_t n)
+{
+    size_t allocSize = roundUpAllocationSize(n, JIT_ALLOCATOR_PAGE_SIZE);
+    
+    Allocation result = systemAlloc(allocSize);
+    if (!result.pages)
+        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 = result.pages + n;
+        m_end = result.pages + allocSize;
+    }
+
+    m_pools.append(result);
+    return result.pages;
+}
+
+}
+
+#endif // ENABLE(JIT) && ENABLE(ASSEMBLER)
+
+#endif // !defined(ExecutableAllocator)