qv4instr_moth_p.h

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant
 
#ifndef QV4INSTR_MOTH_P_H
#define QV4INSTR_MOTH_P_H
 
//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
 
#include <private/qv4staticvalue_p.h>
#include <private/qv4compileddata_p.h> // for CompiledData::CodeOffsetToLine used by the dumper
#include <qendian.h>
 
QT_BEGIN_NAMESPACE
 
#define INSTRUCTION(op, name, nargs, ...)
    op##_INSTRUCTION(name, nargs, __VA_ARGS__)
 
/* for all jump instructions, the offset has to come last, to simplify the job of the bytecode generator */
#define INSTR_Nop(op) INSTRUCTION(op, Nop, 0)
#define INSTR_Ret(op) INSTRUCTION(op, Ret, 0)
#define INSTR_Debug(op) INSTRUCTION(op, Debug, 0)
#define INSTR_LoadConst(op) INSTRUCTION(op, LoadConst, 1, index)
#define INSTR_LoadZero(op) INSTRUCTION(op, LoadZero, 0)
#define INSTR_LoadTrue(op) INSTRUCTION(op, LoadTrue, 0)
#define INSTR_LoadFalse(op) INSTRUCTION(op, LoadFalse, 0)
#define INSTR_LoadNull(op) INSTRUCTION(op, LoadNull, 0)
#define INSTR_LoadUndefined(op) INSTRUCTION(op, LoadUndefined, 0)
#define INSTR_LoadInt(op) INSTRUCTION(op, LoadInt, 1, value)
#define INSTR_MoveConst(op) INSTRUCTION(op, MoveConst, 2, constIndex, destTemp)
#define INSTR_LoadReg(op) INSTRUCTION(op, LoadReg, 1, reg)
#define INSTR_StoreReg(op) INSTRUCTION(op, StoreReg, 1, reg)
#define INSTR_MoveReg(op) INSTRUCTION(op, MoveReg, 2, srcReg, destReg)
#define INSTR_LoadImport(op) INSTRUCTION(op, LoadImport, 1, index)
#define INSTR_LoadLocal(op) INSTRUCTION(op, LoadLocal, 1, index)
#define INSTR_StoreLocal(op) INSTRUCTION(op, StoreLocal, 1, index)
#define INSTR_LoadScopedLocal(op) INSTRUCTION(op, LoadScopedLocal, 2, scope, index)
#define INSTR_StoreScopedLocal(op) INSTRUCTION(op, StoreScopedLocal, 2, scope, index)
#define INSTR_LoadRuntimeString(op) INSTRUCTION(op, LoadRuntimeString, 1, stringId)
#define INSTR_MoveRegExp(op) INSTRUCTION(op, MoveRegExp, 2, regExpId, destReg)
#define INSTR_LoadClosure(op) INSTRUCTION(op, LoadClosure, 1, value)
#define INSTR_LoadName(op) INSTRUCTION(op, LoadName, 1, name)
#define INSTR_LoadGlobalLookup(op) INSTRUCTION(op, LoadGlobalLookup, 1, index)
#define INSTR_LoadQmlContextPropertyLookup(op) INSTRUCTION(op, LoadQmlContextPropertyLookup, 1, index)
#define INSTR_StoreNameSloppy(op) INSTRUCTION(op, StoreNameSloppy, 1, name)
#define INSTR_StoreNameStrict(op) INSTRUCTION(op, StoreNameStrict, 1, name)
#define INSTR_LoadProperty(op) INSTRUCTION(op, LoadProperty, 1, name)
#define INSTR_LoadOptionalProperty(op) INSTRUCTION(op, LoadOptionalProperty, 2, name, offset)
#define INSTR_GetLookup(op) INSTRUCTION(op, GetLookup, 1, index)
#define INSTR_GetOptionalLookup(op) INSTRUCTION(op, GetOptionalLookup, 2, index, offset)
#define INSTR_Yield(op) INSTRUCTION(op, Yield, 0)
#define INSTR_YieldStar(op) INSTRUCTION(op, YieldStar, 0)
#define INSTR_Resume(op) INSTRUCTION(op, Resume, 1, offset)
#define INSTR_IteratorNextForYieldStar(op) INSTRUCTION(op, IteratorNextForYieldStar, 3, iterator, object, offset)
#define INSTR_StoreProperty(op) INSTRUCTION(op, StoreProperty, 2, name, base)
#define INSTR_SetLookup(op) INSTRUCTION(op, SetLookup, 2, index, base)
#define INSTR_LoadSuperProperty(op) INSTRUCTION(op, LoadSuperProperty, 1, property)
#define INSTR_StoreSuperProperty(op) INSTRUCTION(op, StoreSuperProperty, 1, property)
#define INSTR_LoadElement(op) INSTRUCTION(op, LoadElement, 1, base)
#define INSTR_StoreElement(op) INSTRUCTION(op, StoreElement, 2, base, index)
#define INSTR_CallValue(op) INSTRUCTION(op, CallValue, 3, name, argc, argv)
#define INSTR_CallWithReceiver(op) INSTRUCTION(op, CallWithReceiver, 4, name, thisObject, argc, argv)
#define INSTR_CallProperty(op) INSTRUCTION(op, CallProperty, 4, name, base, argc, argv)
#define INSTR_CallPropertyLookup(op) INSTRUCTION(op, CallPropertyLookup, 4, lookupIndex, base, argc, argv)
#define INSTR_CallName(op) INSTRUCTION(op, CallName, 3, name, argc, argv)
#define INSTR_CallPossiblyDirectEval(op) INSTRUCTION(op, CallPossiblyDirectEval, 2, argc, argv)
#define INSTR_CallGlobalLookup(op) INSTRUCTION(op, CallGlobalLookup, 3, index, argc, argv)
#define INSTR_CallQmlContextPropertyLookup(op) INSTRUCTION(op, CallQmlContextPropertyLookup, 3, index, argc, argv)
#define INSTR_CallWithSpread(op) INSTRUCTION(op, CallWithSpread, 4, func, thisObject, argc, argv)
#define INSTR_Construct(op) INSTRUCTION(op, Construct, 3, func, argc, argv)
#define INSTR_ConstructWithSpread(op) INSTRUCTION(op, ConstructWithSpread, 3, func, argc, argv)
#define INSTR_SetUnwindHandler(op) INSTRUCTION(op, SetUnwindHandler, 1, offset)
#define INSTR_UnwindDispatch(op) INSTRUCTION(op, UnwindDispatch, 0)
#define INSTR_UnwindToLabel(op) INSTRUCTION(op, UnwindToLabel, 2, level, offset)
#define INSTR_DeadTemporalZoneCheck(op) INSTRUCTION(op, DeadTemporalZoneCheck, 1, name)
#define INSTR_ThrowException(op) INSTRUCTION(op, ThrowException, 0)
#define INSTR_GetException(op) INSTRUCTION(op, GetException, 0)
#define INSTR_SetException(op) INSTRUCTION(op, SetException, 0)
#define INSTR_CreateCallContext(op) INSTRUCTION(op, CreateCallContext, 0)
#define INSTR_PushCatchContext(op) INSTRUCTION(op, PushCatchContext, 2, index, name)
#define INSTR_PushWithContext(op) INSTRUCTION(op, PushWithContext, 0)
#define INSTR_PushBlockContext(op) INSTRUCTION(op, PushBlockContext, 1, index)
#define INSTR_CloneBlockContext(op) INSTRUCTION(op, CloneBlockContext, 0)
#define INSTR_PushScriptContext(op) INSTRUCTION(op, PushScriptContext, 1, index)
#define INSTR_PopScriptContext(op) INSTRUCTION(op, PopScriptContext, 0)
#define INSTR_PopContext(op) INSTRUCTION(op, PopContext, 0)
#define INSTR_GetIterator(op) INSTRUCTION(op, GetIterator, 1, iterator)
#define INSTR_IteratorNext(op) INSTRUCTION(op, IteratorNext, 2, value, offset)
#define INSTR_IteratorClose(op) INSTRUCTION(op, IteratorClose, 0)
#define INSTR_DestructureRestElement(op) INSTRUCTION(op, DestructureRestElement, 0)
#define INSTR_DeleteProperty(op) INSTRUCTION(op, DeleteProperty, 2, base, index)
#define INSTR_DeleteName(op) INSTRUCTION(op, DeleteName, 1, name)
#define INSTR_TypeofName(op) INSTRUCTION(op, TypeofName, 1, name)
#define INSTR_TypeofValue(op) INSTRUCTION(op, TypeofValue, 0)
#define INSTR_DeclareVar(op) INSTRUCTION(op, DeclareVar, 2, varName, isDeletable)
#define INSTR_DefineArray(op) INSTRUCTION(op, DefineArray, 2, argc, args)
#define INSTR_DefineObjectLiteral(op) INSTRUCTION(op, DefineObjectLiteral, 3, internalClassId, argc, args)
#define INSTR_CreateClass(op) INSTRUCTION(op, CreateClass, 3, classIndex, heritage, computedNames)
#define INSTR_CreateMappedArgumentsObject(op) INSTRUCTION(op, CreateMappedArgumentsObject, 0)
#define INSTR_CreateUnmappedArgumentsObject(op) INSTRUCTION(op, CreateUnmappedArgumentsObject, 0)
#define INSTR_CreateRestParameter(op) INSTRUCTION(op, CreateRestParameter, 1, argIndex)
#define INSTR_ConvertThisToObject(op) INSTRUCTION(op, ConvertThisToObject, 0)
#define INSTR_LoadSuperConstructor(op) INSTRUCTION(op, LoadSuperConstructor, 0)
#define INSTR_ToObject(op) INSTRUCTION(op, ToObject, 0)
#define INSTR_Jump(op) INSTRUCTION(op, Jump, 1, offset)
#define INSTR_JumpTrue(op) INSTRUCTION(op, JumpTrue, 1, offset)
#define INSTR_JumpFalse(op) INSTRUCTION(op, JumpFalse, 1, offset)
#define INSTR_JumpNotUndefined(op) INSTRUCTION(op, JumpNotUndefined, 1, offset)
#define INSTR_JumpNoException(op) INSTRUCTION(op, JumpNoException, 1, offset)
#define INSTR_CheckException(op) INSTRUCTION(op, CheckException, 0)
#define INSTR_CmpEqNull(op) INSTRUCTION(op, CmpEqNull, 0)
#define INSTR_CmpNeNull(op) INSTRUCTION(op, CmpNeNull, 0)
#define INSTR_CmpEqInt(op) INSTRUCTION(op, CmpEqInt, 1, lhs)
#define INSTR_CmpNeInt(op) INSTRUCTION(op, CmpNeInt, 1, lhs)
#define INSTR_CmpEq(op) INSTRUCTION(op, CmpEq, 1, lhs)
#define INSTR_CmpNe(op) INSTRUCTION(op, CmpNe, 1, lhs)
#define INSTR_CmpGt(op) INSTRUCTION(op, CmpGt, 1, lhs)
#define INSTR_CmpGe(op) INSTRUCTION(op, CmpGe, 1, lhs)
#define INSTR_CmpLt(op) INSTRUCTION(op, CmpLt, 1, lhs)
#define INSTR_CmpLe(op) INSTRUCTION(op, CmpLe, 1, lhs)
#define INSTR_CmpStrictEqual(op) INSTRUCTION(op, CmpStrictEqual, 1, lhs)
#define INSTR_CmpStrictNotEqual(op) INSTRUCTION(op, CmpStrictNotEqual, 1, lhs)
#define INSTR_CmpIn(op) INSTRUCTION(op, CmpIn, 1, lhs)
#define INSTR_CmpInstanceOf(op) INSTRUCTION(op, CmpInstanceOf, 1, lhs)
#define INSTR_UNot(op) INSTRUCTION(op, UNot, 0)
#define INSTR_UPlus(op) INSTRUCTION(op, UPlus, 0)
#define INSTR_UMinus(op) INSTRUCTION(op, UMinus, 0)
#define INSTR_UCompl(op) INSTRUCTION(op, UCompl, 0)
#define INSTR_Increment(op) INSTRUCTION(op, Increment, 0)
#define INSTR_Decrement(op) INSTRUCTION(op, Decrement, 0)
#define INSTR_Add(op) INSTRUCTION(op, Add, 1, lhs)
#define INSTR_BitAnd(op) INSTRUCTION(op, BitAnd, 1, lhs)
#define INSTR_BitOr(op) INSTRUCTION(op, BitOr, 1, lhs)
#define INSTR_BitXor(op) INSTRUCTION(op, BitXor, 1, lhs)
#define INSTR_UShr(op) INSTRUCTION(op, UShr, 1, lhs)
#define INSTR_Shr(op) INSTRUCTION(op, Shr, 1, lhs)
#define INSTR_Shl(op) INSTRUCTION(op, Shl, 1, lhs)
#define INSTR_BitAndConst(op) INSTRUCTION(op, BitAndConst, 1, rhs)
#define INSTR_BitOrConst(op) INSTRUCTION(op, BitOrConst, 1, rhs)
#define INSTR_BitXorConst(op) INSTRUCTION(op, BitXorConst, 1, rhs)
#define INSTR_UShrConst(op) INSTRUCTION(op, UShrConst, 1, rhs)
#define INSTR_ShrConst(op) INSTRUCTION(op, ShrConst, 1, rhs)
#define INSTR_ShlConst(op) INSTRUCTION(op, ShlConst, 1, rhs)
#define INSTR_Exp(op) INSTRUCTION(op, Exp, 1, lhs)
#define INSTR_Mul(op) INSTRUCTION(op, Mul, 1, lhs)
#define INSTR_Div(op) INSTRUCTION(op, Div, 1, lhs)
#define INSTR_Mod(op) INSTRUCTION(op, Mod, 1, lhs)
#define INSTR_Sub(op) INSTRUCTION(op, Sub, 1, lhs)
#define INSTR_As(op) INSTRUCTION(op, As, 1, lhs)
#define INSTR_InitializeBlockDeadTemporalZone(op) INSTRUCTION(op, InitializeBlockDeadTemporalZone, 2, firstReg, count)
#define INSTR_ThrowOnNullOrUndefined(op) INSTRUCTION(op, ThrowOnNullOrUndefined, 0)
#define INSTR_GetTemplateObject(op) INSTRUCTION(op, GetTemplateObject, 1, index)
#define INSTR_TailCall(op) INSTRUCTION(op, TailCall, 4, func, thisObject, argc, argv)
 
#define FOR_EACH_MOTH_INSTR_ALL(F)
    F(Nop)
    FOR_EACH_MOTH_INSTR(F)
 
#define FOR_EACH_MOTH_INSTR(F)
    F(Ret)
    F(LoadConst)
    F(LoadZero)
    F(LoadTrue)
    F(LoadFalse)
    F(LoadNull)
    F(LoadUndefined)
    F(LoadInt)
    F(LoadRuntimeString)
    F(MoveConst)
    F(LoadReg)
    F(StoreReg)
    F(MoveReg)
    F(LoadImport)
    F(LoadLocal)
    F(StoreLocal)
    F(LoadScopedLocal)
    F(StoreScopedLocal)
    F(MoveRegExp)
    F(LoadClosure)
    F(LoadName)
    F(LoadGlobalLookup)
    F(LoadQmlContextPropertyLookup)
    F(StoreNameSloppy)
    F(StoreNameStrict)
    F(LoadElement)
    F(StoreElement)
    F(LoadProperty)
    F(LoadOptionalProperty)
    F(GetLookup)
    F(GetOptionalLookup)
    F(StoreProperty)
    F(SetLookup)
    F(LoadSuperProperty)
    F(StoreSuperProperty)
    F(ConvertThisToObject)
    F(ToObject)
    F(Jump)
    F(JumpTrue)
    F(JumpFalse)
    F(JumpNoException)
    F(JumpNotUndefined)
    F(CheckException)
    F(CmpEqNull)
    F(CmpNeNull)
    F(CmpEqInt)
    F(CmpNeInt)
    F(CmpEq)
    F(CmpNe)
    F(CmpGt)
    F(CmpGe)
    F(CmpLt)
    F(CmpLe)
    F(CmpStrictEqual)
    F(CmpStrictNotEqual)
    F(CmpIn)
    F(CmpInstanceOf)
    F(UNot)
    F(UPlus)
    F(UMinus)
    F(UCompl)
    F(Increment)
    F(Decrement)
    F(Add)
    F(BitAnd)
    F(BitOr)
    F(BitXor)
    F(UShr)
    F(Shr)
    F(Shl)
    F(BitAndConst)
    F(BitOrConst)
    F(BitXorConst)
    F(UShrConst)
    F(ShrConst)
    F(ShlConst)
    F(Exp)
    F(Mul)
    F(Div)
    F(Mod)
    F(Sub)
    F(As)
    F(CallValue)
    F(CallWithReceiver)
    F(CallProperty)
    F(CallPropertyLookup)
    F(CallName)
    F(CallPossiblyDirectEval)
    F(CallGlobalLookup)
    F(CallQmlContextPropertyLookup)
    F(CallWithSpread)
    F(Construct)
    F(ConstructWithSpread)
    F(SetUnwindHandler)
    F(UnwindDispatch)
    F(UnwindToLabel)
    F(DeadTemporalZoneCheck)
    F(ThrowException)
    F(GetException)
    F(SetException)
    F(CreateCallContext)
    F(PushCatchContext)
    F(PushWithContext)
    F(PushBlockContext)
    F(CloneBlockContext)
    F(PopContext)
    F(GetIterator)
    F(IteratorNext)
    F(IteratorClose)
    F(DestructureRestElement)
    F(DeleteProperty)
    F(DeleteName)
    F(TypeofName)
    F(TypeofValue)
    F(DeclareVar)
    F(DefineArray)
    F(DefineObjectLiteral)
    F(CreateMappedArgumentsObject)
    F(CreateUnmappedArgumentsObject)
    F(CreateRestParameter)
    F(Yield)
    F(YieldStar)
    F(Resume)
    F(IteratorNextForYieldStar)
    F(CreateClass)
    F(LoadSuperConstructor)
    F(PushScriptContext)
    F(PopScriptContext)
    F(InitializeBlockDeadTemporalZone)
    F(ThrowOnNullOrUndefined)
    F(GetTemplateObject)
    F(TailCall)
    F(Debug)
 
#define MOTH_NUM_INSTRUCTIONS() (static_cast<int>(Moth::Instr::Type::Debug_Wide) + 1)
 
#if defined(Q_CC_GNU)
#if defined(Q_OS_WASM) && !defined(__asmjs)
// Upstream llvm does not support computed goto for the wasm target, unlike the 'fastcomp' llvm fork
// shipped with the emscripten SDK. Disable computed goto usage for non-fastcomp llvm on Wasm.
#else
#  define MOTH_COMPUTED_GOTO
#endif
#endif
 
#define MOTH_INSTR_ALIGN_MASK (alignof(QV4::Moth::Instr) - 1)
 
#define MOTH_INSTR_ENUM(I)  I, I##_Wide,
#define MOTH_INSTR_SIZE(I) (sizeof(QV4::Moth::Instr::instr_##I))
 
#define MOTH_EXPAND_FOR_MSVC(x) x
#define MOTH_DEFINE_ARGS(nargs, ...)
    MOTH_EXPAND_FOR_MSVC(MOTH_DEFINE_ARGS##nargs(__VA_ARGS__))
 
#define MOTH_DEFINE_ARGS0()
#define MOTH_DEFINE_ARGS1(arg)
    int arg;
#define MOTH_DEFINE_ARGS2(arg1, arg2)
    int arg1;
    int arg2;
#define MOTH_DEFINE_ARGS3(arg1, arg2, arg3)
    int arg1;
    int arg2;
    int arg3;
#define MOTH_DEFINE_ARGS4(arg1, arg2, arg3, arg4)
    int arg1;
    int arg2;
    int arg3;
    int arg4;
#define MOTH_DEFINE_ARGS5(arg1, arg2, arg3, arg4, arg5)
    int arg1;
    int arg2;
    int arg3;
    int arg4;
    int arg5;
 
#define MOTH_COLLECT_ENUMS(instr)
    INSTR_##instr(MOTH_GET_ENUM)
#define MOTH_GET_ENUM_INSTRUCTION(name, ...)
    name,
 
#define MOTH_EMIT_STRUCTS(instr)
    INSTR_##instr(MOTH_EMIT_STRUCT)
#define MOTH_EMIT_STRUCT_INSTRUCTION(name, nargs, ...)
    struct instr_##name {
        MOTH_DEFINE_ARGS(nargs, __VA_ARGS__)
    };
 
#define MOTH_EMIT_INSTR_MEMBERS(instr)
    INSTR_##instr(MOTH_EMIT_INSTR_MEMBER)
#define MOTH_EMIT_INSTR_MEMBER_INSTRUCTION(name, nargs, ...)
    instr_##name name;
 
#define MOTH_COLLECT_NARGS(instr)
    INSTR_##instr(MOTH_COLLECT_ARG_COUNT)
#define MOTH_COLLECT_ARG_COUNT_INSTRUCTION(name, nargs, ...)
    nargs, nargs,
 
#define MOTH_DECODE_ARG(arg, type, nargs, offset)
    arg = qFromLittleEndian<type>(qFromUnaligned<type>(reinterpret_cast<const type *>(code) - nargs + offset));
#define MOTH_ADJUST_CODE(type, nargs)
    code += static_cast<quintptr>(nargs*sizeof(type) + 1)
 
#define MOTH_DECODE_INSTRUCTION(name, nargs, ...)
        MOTH_DEFINE_ARGS(nargs, __VA_ARGS__)
    op_int_##name:
        MOTH_ADJUST_CODE(int, nargs);
        MOTH_DECODE_ARGS(name, int, nargs, __VA_ARGS__)
        goto op_main_##name;
    op_byte_##name:
        MOTH_ADJUST_CODE(qint8, nargs);
        MOTH_DECODE_ARGS(name, qint8, nargs, __VA_ARGS__)
    op_main_##name:
        ;
 
#define MOTH_DECODE_WITH_BASE_INSTRUCTION(name, nargs, ...)
        MOTH_DEFINE_ARGS(nargs, __VA_ARGS__)
        const char *base_ptr;
    op_int_##name:
        base_ptr = code;
        MOTH_ADJUST_CODE(int, nargs);
        MOTH_DECODE_ARGS(name, int, nargs, __VA_ARGS__)
        goto op_main_##name;
    op_byte_##name:
        base_ptr = code;
        MOTH_ADJUST_CODE(qint8, nargs);
        MOTH_DECODE_ARGS(name, qint8, nargs, __VA_ARGS__)
    op_main_##name:
        ;
 
#define MOTH_DECODE_ARGS(name, type, nargs, ...)
    MOTH_EXPAND_FOR_MSVC(MOTH_DECODE_ARGS##nargs(name, type, nargs, __VA_ARGS__))
 
#define MOTH_DECODE_ARGS0(name, type, nargs, dummy)
#define MOTH_DECODE_ARGS1(name, type, nargs, arg)
        MOTH_DECODE_ARG(arg, type, nargs, 0);
#define MOTH_DECODE_ARGS2(name, type, nargs, arg1, arg2)
        MOTH_DECODE_ARGS1(name, type, nargs, arg1);
        MOTH_DECODE_ARG(arg2, type, nargs, 1);
#define MOTH_DECODE_ARGS3(name, type, nargs, arg1, arg2, arg3)
        MOTH_DECODE_ARGS2(name, type, nargs, arg1, arg2);
        MOTH_DECODE_ARG(arg3, type, nargs, 2);
#define MOTH_DECODE_ARGS4(name, type, nargs, arg1, arg2, arg3, arg4)
        MOTH_DECODE_ARGS3(name, type, nargs, arg1, arg2, arg3);
        MOTH_DECODE_ARG(arg4, type, nargs, 3);
#define MOTH_DECODE_ARGS5(name, type, nargs, arg1, arg2, arg3, arg4, arg5)
        MOTH_DECODE_ARGS4(name, type, nargs, arg1, arg2, arg3, arg4);
        MOTH_DECODE_ARG(arg5, type, nargs, 4);
 
#ifdef MOTH_COMPUTED_GOTO
/* collect jump labels */
#define COLLECT_LABELS(instr)
    INSTR_##instr(GET_LABEL)
    INSTR_##instr(GET_LABEL_WIDE)
#define GET_LABEL_INSTRUCTION(name, ...)
    &&op_byte_##name,
#define GET_LABEL_WIDE_INSTRUCTION(name, ...)
    &&op_int_##name,
 
#define MOTH_JUMP_TABLE
    static const void *jumpTable[] = {
        FOR_EACH_MOTH_INSTR_ALL(COLLECT_LABELS)
    };
 
#define MOTH_DISPATCH_SINGLE()
    goto *jumpTable[*reinterpret_cast<const uchar *>(code)];
 
#define MOTH_DISPATCH()
    MOTH_DISPATCH_SINGLE()
    op_byte_Nop:
        ++code;
        MOTH_DISPATCH_SINGLE()
    op_int_Nop: /* wide prefix */
        ++code;
        goto *jumpTable[0x100 | *reinterpret_cast<const uchar *>(code)];
#else
#define MOTH_JUMP_TABLE
 
#define MOTH_INSTR_CASE_AND_JUMP(instr)
    INSTR_##instr(GET_CASE_AND_JUMP)
    INSTR_##instr(GET_CASE_AND_JUMP_WIDE)
#define GET_CASE_AND_JUMP_INSTRUCTION(name, ...)
    case Instr::Type::name: goto op_byte_##name;
#define GET_CASE_AND_JUMP_WIDE_INSTRUCTION(name, ...)
    case Instr::Type::name##_Wide: goto op_int_##name;
 
#define MOTH_DISPATCH()
    Instr::Type type = Instr::Type(static_cast<uchar>(*code));
  dispatch:
    switch (type) {
        case Instr::Type::Nop:
            ++code;
            type = Instr::Type(static_cast<uchar>(*code));
            goto dispatch;
        case Instr::Type::Nop_Wide: /* wide prefix */
            ++code;
            type = Instr::Type(0x100 | static_cast<uchar>(*code));
            goto dispatch;
        FOR_EACH_MOTH_INSTR(MOTH_INSTR_CASE_AND_JUMP)
    }
#endif
 
namespace QV4 {
 
namespace CompiledData {
struct CodeOffsetToLineAndStatement;
}
 
namespace Moth {
 
class StackSlot {
    int index;
 
public:
    static StackSlot createRegister(int index) {
        Q_ASSERT(index >= 0);
        StackSlot t;
        t.index = index;
        return t;
    }
 
    int stackSlot() const { return index; }
    operator int() const { return index; }
};
 
inline bool operator==(const StackSlot &l, const StackSlot &r) { return l.stackSlot() == r.stackSlot(); }
inline bool operator!=(const StackSlot &l, const StackSlot &r) { return l.stackSlot() != r.stackSlot(); }
 
// When making changes to the instructions, make sure to bump QV4_DATA_STRUCTURE_VERSION in qv4compileddata_p.h
 
Q_QML_EXPORT
QString dumpBytecode(
        const char *bytecode, int len, int nLocals, int nFormals, int beginOffset, int endOffset,
        const QList<CompiledData::CodeOffsetToLineAndStatement> &lineAndStatementNumberMapping =
                QList<CompiledData::CodeOffsetToLineAndStatement>());
QString dumpBytecode(
        const char *bytecode, int len, int nLocals, int nFormals, int startLine = 1,
        const QList<CompiledData::CodeOffsetToLineAndStatement> &lineAndStatementNumberMapping =
                QList<CompiledData::CodeOffsetToLineAndStatement>());
inline QString dumpBytecode(
        const QByteArray &bytecode, int nLocals, int nFormals, int startLine = 1,
        const QList<CompiledData::CodeOffsetToLineAndStatement> &lineAndStatementNumberMapping =
                QList<CompiledData::CodeOffsetToLineAndStatement>())
{
    return dumpBytecode(bytecode.constData(), bytecode.size(), nLocals, nFormals, startLine,
                        lineAndStatementNumberMapping);
}
 
union Instr
{
    enum class Type {
        FOR_EACH_MOTH_INSTR_ALL(MOTH_INSTR_ENUM)
    };
 
    static Type wideInstructionType(Type t) { return Type(int(t) | 1); }
    static Type narrowInstructionType(Type t) { return Type(int(t) & ~1); }
    static bool isWide(Type t) { return int(t) & 1; }
    static bool isNarrow(Type t) { return !(int(t) & 1); }
    static int encodedLength(Type t) { return int(t) >= 256 ? 2 : 1; }
 
    /*!
     * \internal
     *
     * Bytecode format:
     *
     * Instructions are compacted in the bytecode to save space. Every instruction gets compacted
     * independently. There are many possible layouts coming in 4 main varieties based on two
     * factors:
     *
     * If the instruction's Type <= 255, the OP code is encoded using only one byte.
     * Otherwise, the first byte is 0x1 and the second byte is Type & 0xff.
     *
     * If the instruction takes arguments and they each fit in one byte, encode them this way.
     * Otherwise, each argument is encoded using 4 bytes in little endian. In both cases, only
     * the arguments actually needed by the instruction are encoded.
     * Each instruction type receives two consecutive values in Instr::Type. The even variant has
     * narrow arguments and the odd one has wide arguments and gets the suffix "_Wide".
     *
     * The 4 main formats with arg counts ranging from 0 to 4 (x: OP code bits, abcd: argument bits):
     * 1. 00000001 xxxxxxx0 aaaaaaaa bbbbbbbb cccccccc dddddddd
     * 2. 00000001 xxxxxxx1 aaaaaaaa aaaaaaaa aaaaaaaa aaaaaaaa bbbbbbbb bbbbbbbb bbbbbbbb bbbbbbbb cccccccc cccccccc cccccccc cccccccc dddddddd dddddddd dddddddd dddddddd
     * 3. xxxxxxx0 aaaaaaaa bbbbbbbb cccccccc dddddddd
     * 4. xxxxxxx1 aaaaaaaa aaaaaaaa aaaaaaaa aaaaaaaa bbbbbbbb bbbbbbbb bbbbbbbb bbbbbbbb cccccccc cccccccc cccccccc cccccccc dddddddd dddddddd dddddddd dddddddd
     *
     * 1. Wide instruction OP code, Narrow arguments
     * 2. Wide instruction OP code, Wide arguments
     * 3. Narrow instruction OP code, Narrow arguments
     * 4. Narrow instruction OP code, Wide arguments
     *
     *
     * The current design has a few nice properties:
     * -The argument encoding width can be determined by simply checking for the lowest bit of the
     *  instruction Type.
     * -The 127 first instructions (Nop is first and each instruction has a normal and Wide
     *  argument encoding variant) will have their OP code encoded on 1 byte. This is currently the
     *  vast majority of them. All but the rarest or slowest instructions can therefore have a
     *  compact encoding of their OP code.
     *
     *
     * Examples:
     *
     * LoadInt 127:
     *  LoadInt is the 8th instruction added after Nop. Its value in Type is <= 255 so its OP code
     *  is encoded on 1 byte. It takes one argument which can be encoded losslessly in a signed
     *  byte. It therefore uses narrow argument encoding. Its bytecode encoding in HEX is thus:
     *  10 7f
     *  |  |
     *  |  --> ARG1: 127
     *  -----> OP: 8th instruction; each comes in normal and _Wide variant => 2*8=16 or 0x10
     *
     * LoadInt 128:
     *  This time, not all arguments fit in one byte. Wide argument encoding is used.
     *  The bytecode encoding in HEX is thus.
     *  11 80 00 00 00
     *  |  |  |  |  |
     *  |  -----------> ARG1: Little endian representation of 128 (not in two's complement form)
     *  --------------> OP: The instruction became LoadInt_Wide.
     *
     * InitializeBlockDeadTemporalZone r1, 1
     *  This instruction is the 129th instruction added after Nop. Its value is > 255 so its OP
     *  code is encoded on 2 bytes. It takes 2 arguments which each fit in one byte.
     *  The bytecode encoding in HEX is thus:
     *  01 02 07 01
     *  |  |  |  |
     *  |  |  |  --> ARG2
     *  |  |  -----> ARG1
     *  |  --------> OP: 2-byte OP code -> Type value 258 & 0xff = 2
     *  -----------> OP: 2-byte OP code -> 0x1 prefix
     *
     *
     * See also: QV4_SHOW_BYTECODE and dumpBytecode for much easier debugging
     */
    static Type unpack(const uchar *c) { if (c[0] == 0x1) return Type(0x100 + c[1]); return Type(c[0]); }
    static uchar *pack(uchar *c, Type t) {
        if (uint(t) >= 256) {
            c[0] = 0x1;
            c[1] = uint(t) &0xff;
            return c + 2;
        }
        c[0] = uchar(uint(t));
        return c + 1;
    }
 
    FOR_EACH_MOTH_INSTR_ALL(MOTH_EMIT_STRUCTS)
 
    FOR_EACH_MOTH_INSTR_ALL(MOTH_EMIT_INSTR_MEMBERS)
 
    int argumentsAsInts[4];
};
 
struct InstrInfo
{
    static const int argumentCount[];
    static int size(Instr::Type type);
};
 
template<int N>
struct InstrMeta {
};
 
QT_WARNING_PUSH
QT_WARNING_DISABLE_GCC("-Wuninitialized")
QT_WARNING_DISABLE_GCC("-Wmaybe-uninitialized")
#define MOTH_INSTR_META_TEMPLATE(I)
    template<> struct InstrMeta<int(Instr::Type::I)> {
        enum { Size = MOTH_INSTR_SIZE(I) };
        typedef Instr::instr_##I DataType;
        static const DataType &data(const Instr &instr) { return instr.I; }
        static void setData(Instr &instr, const DataType &v)
        { memcpy(reinterpret_cast<char *>(&instr.I),
                 reinterpret_cast<const char *>(&v),
                 Size); }
    };
FOR_EACH_MOTH_INSTR_ALL(MOTH_INSTR_META_TEMPLATE);
#undef MOTH_INSTR_META_TEMPLATE
QT_WARNING_POP
 
template<int InstrType>
class InstrData : public InstrMeta<InstrType>::DataType
{
};
 
struct Instruction {
#define MOTH_INSTR_DATA_TYPEDEF(I) typedef InstrData<int(Instr::Type::I)> I;
FOR_EACH_MOTH_INSTR_ALL(MOTH_INSTR_DATA_TYPEDEF)
#undef MOTH_INSTR_DATA_TYPEDEF
private:
    Instruction();
};
 
} // namespace Moth
} // namespace QV4
 
QT_END_NAMESPACE
 
#endif // QV4INSTR_MOTH_P_H