1/*
2 * Copyright (C) 2016-2018 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "CatchScope.h"
29#include "StackAlignment.h"
30#include "VM.h"
31
32namespace JSC {
33
34struct EntryFrame;
35
36class SuspendExceptionScope {
37public:
38 SuspendExceptionScope(VM* vm)
39 : m_vm(vm)
40 {
41 auto scope = DECLARE_CATCH_SCOPE(*vm);
42 oldException = scope.exception();
43 scope.clearException();
44 }
45 ~SuspendExceptionScope()
46 {
47 m_vm->restorePreviousException(oldException);
48 }
49private:
50 Exception* oldException;
51 VM* m_vm;
52};
53
54class TopCallFrameSetter {
55public:
56 TopCallFrameSetter(VM& currentVM, CallFrame* callFrame)
57 : vm(currentVM)
58 , oldCallFrame(currentVM.topCallFrame)
59 {
60 currentVM.topCallFrame = callFrame;
61 }
62
63 ~TopCallFrameSetter()
64 {
65 vm.topCallFrame = oldCallFrame;
66 }
67private:
68 VM& vm;
69 CallFrame* oldCallFrame;
70};
71
72ALWAYS_INLINE static void assertStackPointerIsAligned()
73{
74#ifndef NDEBUG
75#if CPU(X86) && !OS(WINDOWS)
76 uintptr_t stackPointer;
77
78 asm("movl %%esp,%0" : "=r"(stackPointer));
79 ASSERT(!(stackPointer % stackAlignmentBytes()));
80#endif
81#endif
82}
83
84class NativeCallFrameTracer {
85public:
86 ALWAYS_INLINE NativeCallFrameTracer(VM* vm, CallFrame* callFrame)
87 {
88 ASSERT(vm);
89 ASSERT(callFrame);
90 ASSERT(reinterpret_cast<void*>(callFrame) < reinterpret_cast<void*>(vm->topEntryFrame));
91 assertStackPointerIsAligned();
92 vm->topCallFrame = callFrame;
93 }
94};
95
96} // namespace JSC
97