/* | |
* Copyright (C) 2009 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 MacroAssemblerCodeRef_h | |
#define MacroAssemblerCodeRef_h | |
#include "ExecutableAllocator.h" | |
#include "PassRefPtr.h" | |
#include "RefPtr.h" | |
#include "UnusedParam.h" | |
#if ENABLE(ASSEMBLER) | |
// ASSERT_VALID_CODE_POINTER checks that ptr is a non-null pointer, and that it is a valid | |
// instruction address on the platform (for example, check any alignment requirements). | |
#if CPU(ARM_THUMB2) | |
// ARM/thumb instructions must be 16-bit aligned, but all code pointers to be loaded | |
// into the processor are decorated with the bottom bit set, indicating that this is | |
// thumb code (as oposed to 32-bit traditional ARM). The first test checks for both | |
// decorated and undectorated null, and the second test ensures that the pointer is | |
// decorated. | |
#define ASSERT_VALID_CODE_POINTER(ptr) \ | |
ASSERT(reinterpret_cast<intptr_t>(ptr) & ~1); \ | |
ASSERT(reinterpret_cast<intptr_t>(ptr) & 1) | |
#define ASSERT_VALID_CODE_OFFSET(offset) \ | |
ASSERT(!(offset & 1)) // Must be multiple of 2. | |
#else | |
#define ASSERT_VALID_CODE_POINTER(ptr) \ | |
ASSERT(ptr) | |
#define ASSERT_VALID_CODE_OFFSET(offset) // Anything goes! | |
#endif | |
namespace JSC { | |
// FunctionPtr: | |
// | |
// FunctionPtr should be used to wrap pointers to C/C++ functions in JSC | |
// (particularly, the stub functions). | |
class FunctionPtr { | |
public: | |
FunctionPtr() | |
: m_value(0) | |
{ | |
} | |
template<typename FunctionType> | |
explicit FunctionPtr(FunctionType* value) | |
#if COMPILER(RVCT) | |
// RVTC compiler needs C-style cast as it fails with the following error | |
// Error: #694: reinterpret_cast cannot cast away const or other type qualifiers | |
: m_value((void*)(value)) | |
#else | |
: m_value(reinterpret_cast<void*>(value)) | |
#endif | |
{ | |
ASSERT_VALID_CODE_POINTER(m_value); | |
} | |
void* value() const { return m_value; } | |
void* executableAddress() const { return m_value; } | |
private: | |
void* m_value; | |
}; | |
// ReturnAddressPtr: | |
// | |
// ReturnAddressPtr should be used to wrap return addresses generated by processor | |
// 'call' instructions exectued in JIT code. We use return addresses to look up | |
// exception and optimization information, and to repatch the call instruction | |
// that is the source of the return address. | |
class ReturnAddressPtr { | |
public: | |
ReturnAddressPtr() | |
: m_value(0) | |
{ | |
} | |
explicit ReturnAddressPtr(void* value) | |
: m_value(value) | |
{ | |
ASSERT_VALID_CODE_POINTER(m_value); | |
} | |
explicit ReturnAddressPtr(FunctionPtr function) | |
: m_value(function.value()) | |
{ | |
ASSERT_VALID_CODE_POINTER(m_value); | |
} | |
void* value() const { return m_value; } | |
private: | |
void* m_value; | |
}; | |
// MacroAssemblerCodePtr: | |
// | |
// MacroAssemblerCodePtr should be used to wrap pointers to JIT generated code. | |
class MacroAssemblerCodePtr { | |
public: | |
MacroAssemblerCodePtr() | |
: m_value(0) | |
{ | |
} | |
explicit MacroAssemblerCodePtr(void* value) | |
#if CPU(ARM_THUMB2) | |
// Decorate the pointer as a thumb code pointer. | |
: m_value(reinterpret_cast<char*>(value) + 1) | |
#else | |
: m_value(value) | |
#endif | |
{ | |
ASSERT_VALID_CODE_POINTER(m_value); | |
} | |
explicit MacroAssemblerCodePtr(ReturnAddressPtr ra) | |
: m_value(ra.value()) | |
{ | |
ASSERT_VALID_CODE_POINTER(m_value); | |
} | |
void* executableAddress() const { return m_value; } | |
#if CPU(ARM_THUMB2) | |
// To use this pointer as a data address remove the decoration. | |
void* dataLocation() const { ASSERT_VALID_CODE_POINTER(m_value); return reinterpret_cast<char*>(m_value) - 1; } | |
#else | |
void* dataLocation() const { ASSERT_VALID_CODE_POINTER(m_value); return m_value; } | |
#endif | |
bool operator!() | |
{ | |
return !m_value; | |
} | |
private: | |
void* m_value; | |
}; | |
// MacroAssemblerCodeRef: | |
// | |
// A reference to a section of JIT generated code. A CodeRef consists of a | |
// pointer to the code, and a ref pointer to the pool from within which it | |
// was allocated. | |
class MacroAssemblerCodeRef { | |
public: | |
MacroAssemblerCodeRef() | |
: m_size(0) | |
{ | |
} | |
MacroAssemblerCodeRef(void* code, PassRefPtr<ExecutablePool> executablePool, size_t size) | |
: m_code(code) | |
, m_executablePool(executablePool) | |
, m_size(size) | |
{ | |
} | |
MacroAssemblerCodePtr m_code; | |
RefPtr<ExecutablePool> m_executablePool; | |
size_t m_size; | |
}; | |
} // namespace JSC | |
#endif // ENABLE(ASSEMBLER) | |
#endif // MacroAssemblerCodeRef_h |