/*

* Copyright (C) 2016 Yusuke Suzuki <utatane.tea@gmail.com>

* Copyright (C) 2016-2023 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 "CachedCall.h"

#include "Exception.h"

#include "FunctionCodeBlock.h"

#include "FunctionExecutable.h"

#include "Instruction.h"

#include "Interpreter.h"

#include "JSCPtrTag.h"

#include "LLIntData.h"

#include "LLIntThunks.h"

#include "ProtoCallFrameInlines.h"

#include "StackAlignment.h"

#include "UnlinkedCodeBlock.h"

#include "VMTrapsInlines.h"

#include <wtf/UnalignedAccess.h>

namespace JSC {

ALWAYS_INLINE VM& Interpreter::vm()

{

return *bitwise_cast<VM*>(bitwise_cast<uint8_t*>(this) - OBJECT_OFFSETOF(VM, interpreter));

}

inline CallFrame* calleeFrameForVarargs(CallFrame* callFrame, unsigned numUsedStackSlots, unsigned argumentCountIncludingThis)

{

// We want the new frame to be allocated on a stack aligned offset with a stack

// aligned size. Align the size here.

argumentCountIncludingThis = WTF::roundUpToMultipleOf(

stackAlignmentRegisters(),

argumentCountIncludingThis + CallFrame::headerSizeInRegisters) - CallFrame::headerSizeInRegisters;

// Align the frame offset here.

unsigned paddedCalleeFrameOffset = WTF::roundUpToMultipleOf(

stackAlignmentRegisters(),

numUsedStackSlots + argumentCountIncludingThis + CallFrame::headerSizeInRegisters);

return CallFrame::create(callFrame->registers() - paddedCalleeFrameOffset);

}

inline Opcode Interpreter::getOpcode(OpcodeID id)

{

return LLInt::getOpcode(id);

}

// This function is only available as a debugging tool for development work.

// It is not currently used except in a RELEASE_ASSERT to ensure that it is

// working properly.

inline OpcodeID Interpreter::getOpcodeID(Opcode opcode)

{

#if ENABLE(COMPUTED_GOTO_OPCODES)

ASSERT(isOpcode(opcode));

#if ENABLE(LLINT_EMBEDDED_OPCODE_ID)

// The OpcodeID is embedded in the int32_t word preceding the location of

// the LLInt code for the opcode (see the EMBED_OPCODE_ID_IF_NEEDED macro

// in LowLevelInterpreter.cpp).

const void* opcodeAddress = removeCodePtrTag(bitwise_cast<const void*>(opcode));

const int32_t* opcodeIDAddress = bitwise_cast<int32_t*>(opcodeAddress) - 1;

OpcodeID opcodeID = static_cast<OpcodeID>(WTF::unalignedLoad<int32_t>(opcodeIDAddress));

ASSERT(opcodeID < NUMBER_OF_BYTECODE_IDS);

return opcodeID;

#else

return opcodeIDTable().get(opcode);

#endif // ENABLE(LLINT_EMBEDDED_OPCODE_ID)

#else // not ENABLE(COMPUTED_GOTO_OPCODES)

return opcode;

#endif

}

ALWAYS_INLINE JSValue Interpreter::executeCachedCall(CachedCall& cachedCall)

{

VM& vm = this->vm();

auto throwScope = DECLARE_THROW_SCOPE(vm);

ASSERT(!vm.isCollectorBusyOnCurrentThread());

ASSERT(vm.currentThreadIsHoldingAPILock());

StackStats::CheckPoint stackCheckPoint;

auto clobberizeValidator = makeScopeExit([&] {

vm.didEnterVM = true;

});

if (UNLIKELY(vm.traps().needHandling(VMTraps::NonDebuggerAsyncEvents))) {

if (vm.hasExceptionsAfterHandlingTraps())

return throwScope.exception();

}

if (UNLIKELY(!cachedCall.m_addressForCall)) {

DeferTraps deferTraps(vm); // We can't jettison this code if we're about to run it.

cachedCall.relink();

RETURN_IF_EXCEPTION(throwScope, throwScope.exception());

}

// Execute the code:

throwScope.release();

return JSValue::decode(vmEntryToJavaScript(cachedCall.m_addressForCall, &vm, &cachedCall.m_protoCallFrame));

}

} // namespace JSC