#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;
}
};
class NativeCallFrameTracerWithRestore {
public:
ALWAYS_INLINE NativeCallFrameTracerWithRestore(VM* vm, EntryFrame* EntryFrame, CallFrame* callFrame)
: m_vm(vm)
{
ASSERT(vm);
ASSERT(callFrame);
assertStackPointerIsAligned();
m_savedTopEntryFrame = vm->topEntryFrame;
m_savedTopCallFrame = vm->topCallFrame;
vm->topEntryFrame = EntryFrame;
vm->topCallFrame = callFrame;
}
ALWAYS_INLINE ~NativeCallFrameTracerWithRestore()
{
m_vm->topEntryFrame = m_savedTopEntryFrame;
m_vm->topCallFrame = m_savedTopCallFrame;
}
private:
VM* m_vm;
EntryFrame* m_savedTopEntryFrame;
CallFrame* m_savedTopCallFrame;
};
}