/* * Copyright (C) 2016-2018 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. */ #pragma once #include "CatchScope.h" #include "StackAlignment.h" #include "VM.h" namespace JSC { struct EntryFrame; class SuspendExceptionScope { public: SuspendExceptionScope(VM* vm) : m_vm(vm) { auto scope = DECLARE_CATCH_SCOPE(*vm); oldException = scope.exception(); scope.clearException(); } ~SuspendExceptionScope() { m_vm->restorePreviousException(oldException); } private: Exception* oldException; VM* m_vm; }; class TopCallFrameSetter { public: TopCallFrameSetter(VM& currentVM, CallFrame* callFrame) : vm(currentVM) , oldCallFrame(currentVM.topCallFrame) { currentVM.topCallFrame = callFrame; } ~TopCallFrameSetter() { vm.topCallFrame = oldCallFrame; } private: VM& vm; CallFrame* oldCallFrame; }; ALWAYS_INLINE static void assertStackPointerIsAligned() { #ifndef NDEBUG #if CPU(X86) && !OS(WINDOWS) uintptr_t stackPointer; asm("movl %%esp,%0" : "=r"(stackPointer)); ASSERT(!(stackPointer % stackAlignmentBytes())); #endif #endif } class NativeCallFrameTracer { public: ALWAYS_INLINE NativeCallFrameTracer(VM* vm, CallFrame* callFrame) { ASSERT(vm); ASSERT(callFrame); ASSERT(reinterpret_cast<void*>(callFrame) < reinterpret_cast<void*>(vm->topEntryFrame)); assertStackPointerIsAligned(); vm->topCallFrame = callFrame; } }; } // namespace JSC