#include "pocketpy/interpreter/ceval.hpp"

namespace pkpy{

#define PREDICT_INT_OP(op)                          \
    if(is_int(_0) && is_int(_1)){                   \
        TOP() = VAR(_0.as<i64>() op _1.as<i64>());  \
        DISPATCH()                                  \
    }

#define PREDICT_INT_DIV_OP(op)                      \
    if(is_int(_0) && is_int(_1)){                   \
        i64 divisor = _1.as<i64>();                 \
        if(divisor == 0) ZeroDivisionError();       \
        TOP() = VAR(_0.as<i64>() op divisor);       \
        DISPATCH()                                  \
    }

#define BINARY_F_COMPARE(func, op, rfunc)                           \
        PyVar ret;                                                  \
        const PyTypeInfo* _ti = _tp_info(_0);                       \
        if(_ti->m##func){                                           \
            ret = _ti->m##func(this, _0, _1);                       \
        }else{                                                      \
            PyVar self;                                                         \
            PyVar _2 = get_unbound_method(_0, func, &self, false);              \
            if(_2 != nullptr) ret = call_method(self, _2, _1);                  \
            else ret = NotImplemented;                                          \
        }                                                                       \
        if(is_not_implemented(ret)){                                            \
            PyVar self;                                                         \
            PyVar _2 = get_unbound_method(_1, rfunc, &self, false);             \
            if(_2 != nullptr) ret = call_method(self, _2, _0);                  \
            else BinaryOptError(op, _0, _1);                                    \
            if(is_not_implemented(ret)) BinaryOptError(op, _0, _1);             \
        }


void VM::__op_unpack_sequence(uint16_t arg){
    PyVar _0 = POPX();
    if(is_type(_0, VM::tp_tuple)){
        // fast path for tuple
        Tuple& tuple = PK_OBJ_GET(Tuple, _0);
        if(tuple.size() == arg){
            for(PyVar obj: tuple) PUSH(obj);
        }else{
            ValueError(_S("expected ", (int)arg, " values to unpack, got ", (int)tuple.size()));
        }
    }else{
        auto _lock = heap.gc_scope_lock();  // lock the gc via RAII!!
        _0 = py_iter(_0);
        const PyTypeInfo* ti = _tp_info(_0);
        for(int i=0; i<arg; i++){
            PyVar _1 = _py_next(ti, _0);
            if(_1 == StopIteration) ValueError("not enough values to unpack");
            PUSH(_1);
        }
        if(_py_next(ti, _0) != StopIteration) ValueError("too many values to unpack");
    }
}

bool VM::py_lt(PyVar _0, PyVar _1){
    BINARY_F_COMPARE(__lt__, "<", __gt__);
    return ret == True;
}

bool VM::py_le(PyVar _0, PyVar _1){
    BINARY_F_COMPARE(__le__, "<=", __ge__);
    return ret == True;
}

bool VM::py_gt(PyVar _0, PyVar _1){
    BINARY_F_COMPARE(__gt__, ">", __lt__);
    return ret == True;
}

bool VM::py_ge(PyVar _0, PyVar _1){
    BINARY_F_COMPARE(__ge__, ">=", __le__);
    return ret == True;
}

#undef BINARY_F_COMPARE

#if PK_ENABLE_PROFILER
#define CEVAL_STEP_CALLBACK()                                           \
    if(_ceval_on_step) _ceval_on_step(this, frame, byte);               \
    if(_profiler) _profiler->_step(callstack.size(), frame);            \
    if(!_next_breakpoint.empty()) { _next_breakpoint._step(this); }
#else
#define CEVAL_STEP_CALLBACK()   \
    if(_ceval_on_step && _ceval_on_step){         \
        if(_ceval_on_step) \
        if(_ceval_on_step) _ceval_on_step(this, frame, byte);   \
    }
#endif

#define DISPATCH() { frame->_ip++; goto __NEXT_STEP; }
#define DISPATCH_JUMP(__offset) { frame->_ip+=__offset; goto __NEXT_STEP; }
#define DISPATCH_JUMP_ABSOLUTE(__target) { frame->_ip=&frame->co->codes[__target]; goto __NEXT_STEP; }

PyVar VM::__run_top_frame(){
    Frame* frame = &callstack.top();
    const Frame* base_frame = frame;
    InternalException __internal_exception;

    while(true){
        try{
/**********************************************************************/
{
__NEXT_FRAME:
    Bytecode byte;

    if(__internal_exception.type == InternalExceptionType::Null){
        // None
        frame->_ip++;
    }else if(__internal_exception.type == InternalExceptionType::Handled){
        // HandledException + continue
        frame->_ip = &frame->co->codes[__internal_exception.arg];
        __internal_exception = {};
    }else{
        // UnhandledException + continue (need_raise = true)
        // ToBeRaisedException + continue (need_raise = true)
        __internal_exception = {};
        __raise_exc();      // no return
    }

__NEXT_STEP:
    byte = *frame->_ip;
    CEVAL_STEP_CALLBACK()

#if PK_DEBUG_CEVAL_STEP
    __log_s_data();
#endif
    switch ((Opcode)byte.op)
    {
    case OP_NO_OP: DISPATCH()
    /*****************************************/
    case OP_POP_TOP: POP(); DISPATCH()
    case OP_DUP_TOP: PUSH(TOP()); DISPATCH()
    case OP_DUP_TOP_TWO:
        // [a, b]
        PUSH(SECOND()); // [a, b, a]
        PUSH(SECOND()); // [a, b, a, b]
        DISPATCH()
    case OP_ROT_TWO: std::swap(TOP(), SECOND()); DISPATCH()
    case OP_ROT_THREE:{
        // [a, b, c] -> [c, a, b]
        PyVar _0 = TOP();
        TOP() = SECOND();
        SECOND() = THIRD();
        THIRD() = _0;
    } DISPATCH()
    case OP_PRINT_EXPR:
        if(TOP() != None) stdout_write(py_repr(TOP()) + "\n");
        POP();
        DISPATCH()
    /*****************************************/
    case OP_LOAD_CONST:
        PUSH(frame->co->consts[byte.arg]);
        DISPATCH()
    case OP_LOAD_NONE:       PUSH(None); DISPATCH()
    case OP_LOAD_TRUE:       PUSH(True); DISPATCH()
    case OP_LOAD_FALSE:      PUSH(False); DISPATCH()
    /*****************************************/
    case OP_LOAD_SMALL_INT:
        s_data.emplace(tp_int, (i64)(int16_t)byte.arg);
        DISPATCH()
    /*****************************************/
    case OP_LOAD_ELLIPSIS:   PUSH(Ellipsis); DISPATCH()
    case OP_LOAD_FUNCTION: {
        const FuncDecl_& decl = frame->co->func_decls[byte.arg];
        PyVar obj;
        if(decl->nested){
            NameDict_ captured = frame->_locals.to_namedict();
            obj = VAR(Function(decl, frame->_module, nullptr, captured));
            captured->set(decl->code->name, obj);
        }else{
            obj = VAR(Function(decl, frame->_module, nullptr, nullptr));
        }
        PUSH(obj);
    } DISPATCH()
    case OP_LOAD_NULL: PUSH(PY_NULL); DISPATCH()
    /*****************************************/
    case OP_LOAD_FAST: {
        PyVar _0 = frame->_locals[byte.arg];
        if(_0 == PY_NULL) vm->UnboundLocalError(frame->co->varnames[byte.arg]);
        PUSH(_0);
    } DISPATCH()
    case OP_LOAD_NAME: {
        StrName _name(byte.arg);
        PyVar* slot = frame->_locals.try_get_name(_name);
        if(slot != nullptr) {
            if(*slot == PY_NULL) vm->UnboundLocalError(_name);
            PUSH(*slot);
            DISPATCH()
        }
        PyVar* _0 = frame->f_closure_try_get(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        _0 = frame->f_globals().try_get_2_likely_found(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        _0 = vm->builtins->attr().try_get_2_likely_found(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        vm->NameError(_name);
    } DISPATCH()
    case OP_LOAD_NONLOCAL: {
        StrName _name(byte.arg);
        PyVar* _0 = frame->f_closure_try_get(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        _0 = frame->f_globals().try_get_2_likely_found(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        _0 = vm->builtins->attr().try_get_2_likely_found(_name);
        if(_0 != nullptr) { PUSH(*_0); DISPATCH() }
        vm->NameError(_name);
    } DISPATCH()
    case OP_LOAD_GLOBAL:{
        StrName _name(byte.arg);
        PyVar _0 = frame->f_globals().try_get_likely_found(_name);
        if(_0 != nullptr) { PUSH(_0); DISPATCH() }
        _0 = vm->builtins->attr().try_get_likely_found(_name);
        if(_0 != nullptr) { PUSH(_0); DISPATCH() }
        vm->NameError(_name);
    } DISPATCH()
    case OP_LOAD_ATTR:{
        TOP() = getattr(TOP(), StrName(byte.arg));
    } DISPATCH()
    case OP_LOAD_CLASS_GLOBAL:{
        assert(__curr_class != nullptr);
        StrName _name(byte.arg);
        PyVar _0 = getattr(__curr_class, _name, false);
        if(_0 != nullptr) { PUSH(_0); DISPATCH() }
        // load global if attribute not found
        _0 = frame->f_globals().try_get_likely_found(_name);
        if(_0 != nullptr) { PUSH(_0); DISPATCH() }
        _0 = vm->builtins->attr().try_get_likely_found(_name);
        if(_0 != nullptr) { PUSH(_0); DISPATCH() }
        vm->NameError(_name);
    } DISPATCH()
    case OP_LOAD_METHOD:{
        PyVar _0;
        TOP() = get_unbound_method(TOP(), StrName(byte.arg), &_0, true, true);
        PUSH(_0);
    }DISPATCH()
    case OP_LOAD_SUBSCR:{
        PyVar _1 = POPX();    // b
        PyVar _0 = TOP();     // a
        auto _ti = _tp_info(_0);
        if(_ti->m__getitem__){
            TOP() = _ti->m__getitem__(this, _0, _1);
        }else{
            TOP() = call_method(_0, __getitem__, _1);
        }
    } DISPATCH()
    case OP_LOAD_SUBSCR_FAST:{
        PyVar _1 = frame->_locals[byte.arg];
        if(_1 == PY_NULL) vm->UnboundLocalError(frame->co->varnames[byte.arg]);
        PyVar _0 = TOP();     // a
        auto _ti = _tp_info(_0);
        if(_ti->m__getitem__){
            TOP() = _ti->m__getitem__(this, _0, _1);
        }else{
            TOP() = call_method(_0, __getitem__, _1);
        }
    } DISPATCH()
    case OP_LOAD_SUBSCR_SMALL_INT:{
        PyVar _1 = VAR((int16_t)byte.arg);
        PyVar _0 = TOP();     // a
        auto _ti = _tp_info(_0);
        if(_ti->m__getitem__){
            TOP() = _ti->m__getitem__(this, _0, _1);
        }else{
            TOP() = call_method(_0, __getitem__, _1);
        }
    } DISPATCH()
    case OP_STORE_FAST:
        frame->_locals[byte.arg] = POPX();
        DISPATCH()
    case OP_STORE_NAME:{
        StrName _name(byte.arg);
        PyVar _0 = POPX();
        if(frame->_callable != nullptr){
            PyVar* slot = frame->_locals.try_get_name(_name);
            if(slot != nullptr){
                *slot = _0;     // store in locals if possible
            }else{
                Function& func = frame->_callable->as<Function>();
                if(func.decl == __dynamic_func_decl){
                    assert(func._closure != nullptr);
                    func._closure->set(_name, _0);
                }else{
                    vm->NameError(_name);
                }
            }
        }else{
            frame->f_globals().set(_name, _0);
        }
    } DISPATCH()
    case OP_STORE_GLOBAL:
        frame->f_globals().set(StrName(byte.arg), POPX());
        DISPATCH()
    case OP_STORE_ATTR: {
        PyVar _0 = TOP();         // a
        PyVar _1 = SECOND();      // val
        setattr(_0, StrName(byte.arg), _1);
        STACK_SHRINK(2);
    } DISPATCH()
    case OP_STORE_SUBSCR:{
        PyVar _2 = POPX();        // b
        PyVar _1 = POPX();        // a
        PyVar _0 = POPX();        // val
        auto _ti = _tp_info(_1);
        if(_ti->m__setitem__){
            _ti->m__setitem__(this, _1, _2, _0);
        }else{
            call_method(_1, __setitem__, _2, _0);
        }
    }DISPATCH()
    case OP_STORE_SUBSCR_FAST:{
        PyVar _2 = frame->_locals[byte.arg];    // b
        if(_2 == PY_NULL) vm->UnboundLocalError(frame->co->varnames[byte.arg]);
        PyVar _1 = POPX();        // a
        PyVar _0 = POPX();        // val
        auto _ti = _tp_info(_1);
        if(_ti->m__setitem__){
            _ti->m__setitem__(this, _1, _2, _0);
        }else{
            call_method(_1, __setitem__, _2, _0);
        }
    }DISPATCH()
    case OP_DELETE_FAST:{
        PyVar _0 = frame->_locals[byte.arg];
        if(_0 == PY_NULL) vm->UnboundLocalError(frame->co->varnames[byte.arg]);
        frame->_locals[byte.arg].set_null();
    }DISPATCH()
    case OP_DELETE_NAME:{
        StrName _name(byte.arg);
        if(frame->_callable != nullptr){
            PyVar* slot = frame->_locals.try_get_name(_name);
            if(slot != nullptr){
                slot->set_null();
            }else{
                Function& func = frame->_callable->as<Function>();
                if(func.decl == __dynamic_func_decl){
                    assert(func._closure != nullptr);
                    bool ok = func._closure->del(_name);
                    if(!ok) vm->NameError(_name);
                }else{
                    vm->NameError(_name);
                }
            }
        }else{
            if(!frame->f_globals().del(_name)) vm->NameError(_name);
        }
    } DISPATCH()
    case OP_DELETE_GLOBAL:{
        StrName _name(byte.arg);
        if(!frame->f_globals().del(_name)) vm->NameError(_name);
    }DISPATCH()
    case OP_DELETE_ATTR:{
        PyVar _0 = POPX();
        delattr(_0, StrName(byte.arg));
    } DISPATCH()
    case OP_DELETE_SUBSCR:{
        PyVar _1 = POPX();
        PyVar _0 = POPX();
        auto _ti = _tp_info(_0);
        if(_ti->m__delitem__){
            _ti->m__delitem__(this, _0, _1);
        }else{
            call_method(_0, __delitem__, _1);
        }
    }DISPATCH()
    /*****************************************/
    case OP_BUILD_LONG: {
        PyVar _0 = builtins->attr().try_get_likely_found(pk_id_long);
        if(_0 == nullptr) AttributeError(builtins, pk_id_long);
        TOP() = call(_0, TOP());
    } DISPATCH()
    case OP_BUILD_IMAG: {
        PyVar _0 = builtins->attr().try_get_likely_found(pk_id_complex);
        if(_0 == nullptr) AttributeError(builtins, pk_id_long);
        TOP() = call(_0, VAR(0), TOP());
    } DISPATCH()
    case OP_BUILD_BYTES: {
        const Str& s = CAST(Str&, TOP());
        unsigned char* p = (unsigned char*)std::malloc(s.size);
        std::memcpy(p, s.data, s.size);
        TOP() = VAR(Bytes(p, s.size));
    } DISPATCH()
    case OP_BUILD_TUPLE:{
        PyVar _0 = VAR(STACK_VIEW(byte.arg).to_tuple());
        STACK_SHRINK(byte.arg);
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_LIST:{
        PyVar _0 = VAR(STACK_VIEW(byte.arg).to_list());
        STACK_SHRINK(byte.arg);
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_DICT:{
        if(byte.arg == 0){
            PUSH(VAR(Dict()));
            DISPATCH()
        }
        PyVar _0 = VAR(STACK_VIEW(byte.arg).to_list());
        _0 = call(_t(tp_dict), _0);
        STACK_SHRINK(byte.arg);
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_SET:{
        PyVar _0 = VAR(STACK_VIEW(byte.arg).to_list());
        _0 = call(builtins->attr(pk_id_set), _0);
        STACK_SHRINK(byte.arg);
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_SLICE:{
        PyVar _2 = POPX();    // step
        PyVar _1 = POPX();    // stop
        PyVar _0 = POPX();    // start
        PUSH(VAR(Slice(_0, _1, _2)));
    } DISPATCH()
    case OP_BUILD_STRING: {
        SStream ss;
        ArgsView view = STACK_VIEW(byte.arg);
        for(PyVar obj : view) ss << py_str(obj);
        STACK_SHRINK(byte.arg);
        PUSH(VAR(ss.str()));
    } DISPATCH()
    /*****************************************/
    case OP_BUILD_TUPLE_UNPACK: {
        List list;
        __unpack_as_list(STACK_VIEW(byte.arg), list);
        STACK_SHRINK(byte.arg);
        PyVar _0 = VAR(list.to_tuple());
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_LIST_UNPACK: {
        List list;
        __unpack_as_list(STACK_VIEW(byte.arg), list);
        STACK_SHRINK(byte.arg);
        PyVar _0 = VAR(std::move(list));
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_DICT_UNPACK: {
        Dict dict;
        __unpack_as_dict(STACK_VIEW(byte.arg), dict);
        STACK_SHRINK(byte.arg);
        PyVar _0 = VAR(std::move(dict));
        PUSH(_0);
    } DISPATCH()
    case OP_BUILD_SET_UNPACK: {
        List list;
        __unpack_as_list(STACK_VIEW(byte.arg), list);
        STACK_SHRINK(byte.arg);
        PyVar _0 = VAR(std::move(list));
        _0 = call(builtins->attr(pk_id_set), _0);
        PUSH(_0);
    } DISPATCH()
    /*****************************************/
#define BINARY_OP_SPECIAL(func)                         \
        _ti = _tp_info(_0);                             \
        if(_ti->m##func){                               \
            TOP() = _ti->m##func(this, _0, _1);         \
        }else{                                          \
            PyVar self;                                             \
            PyVar _2 = get_unbound_method(_0, func, &self, false);  \
            if(_2 != nullptr) TOP() = call_method(self, _2, _1);    \
            else TOP() = NotImplemented;                            \
        }

#define BINARY_OP_RSPECIAL(op, func)                                    \
        if(is_not_implemented(TOP())){                                  \
            PyVar self;                                                 \
            PyVar _2 = get_unbound_method(_1, func, &self, false);      \
            if(_2 != nullptr) TOP() = call_method(self, _2, _0);        \
            else BinaryOptError(op, _0, _1);                            \
            if(is_not_implemented(TOP())) BinaryOptError(op, _0, _1);   \
        }

    case OP_BINARY_TRUEDIV:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__truediv__);
        if(is_not_implemented(TOP())) BinaryOptError("/", _0, _1);
    } DISPATCH()
    case OP_BINARY_POW:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__pow__);
        if(is_not_implemented(TOP())) BinaryOptError("**", _0, _1);
    } DISPATCH()
    case OP_BINARY_ADD:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(+)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__add__);
        BINARY_OP_RSPECIAL("+", __radd__);
    } DISPATCH()
    case OP_BINARY_SUB:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(-)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__sub__);
        BINARY_OP_RSPECIAL("-", __rsub__);
    } DISPATCH()
    case OP_BINARY_MUL:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(*)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__mul__);
        BINARY_OP_RSPECIAL("*", __rmul__);
    } DISPATCH()
    case OP_BINARY_FLOORDIV:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_DIV_OP(/)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__floordiv__);
        if(is_not_implemented(TOP())) BinaryOptError("//", _0, _1);
    } DISPATCH()
    case OP_BINARY_MOD:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_DIV_OP(%)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__mod__);
        if(is_not_implemented(TOP())) BinaryOptError("%", _0, _1);
    } DISPATCH()
    case OP_COMPARE_LT:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(<)
        TOP() = VAR(py_lt(_0, _1));
    } DISPATCH()
    case OP_COMPARE_LE:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(<=)
        TOP() = VAR(py_le(_0, _1));
    } DISPATCH()
    case OP_COMPARE_EQ:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        TOP() = VAR(py_eq(_0, _1));
    } DISPATCH()
    case OP_COMPARE_NE:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        TOP() = VAR(py_ne(_0, _1));
    } DISPATCH()
    case OP_COMPARE_GT:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(>)
        TOP() = VAR(py_gt(_0, _1));
    } DISPATCH()
    case OP_COMPARE_GE:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(>=)
        TOP() = VAR(py_ge(_0, _1));
    } DISPATCH()
    case OP_BITWISE_LSHIFT:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(<<)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__lshift__);
        if(is_not_implemented(TOP())) BinaryOptError("<<", _0, _1);
    } DISPATCH()
    case OP_BITWISE_RSHIFT:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(>>)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__rshift__);
        if(is_not_implemented(TOP())) BinaryOptError(">>", _0, _1);
    } DISPATCH()
    case OP_BITWISE_AND:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(&)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__and__);
        if(is_not_implemented(TOP())) BinaryOptError("&", _0, _1);
    } DISPATCH()
    case OP_BITWISE_OR:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(|)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__or__);
        if(is_not_implemented(TOP())) BinaryOptError("|", _0, _1);
    } DISPATCH()
    case OP_BITWISE_XOR:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        PREDICT_INT_OP(^)
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__xor__);
        if(is_not_implemented(TOP())) BinaryOptError("^", _0, _1);
    } DISPATCH()
    case OP_BINARY_MATMUL:{
        PyVar _1 = POPX();
        PyVar _0 = TOP();
        const PyTypeInfo* _ti;
        BINARY_OP_SPECIAL(__matmul__);
        if(is_not_implemented(TOP())) BinaryOptError("@", _0, _1);
    } DISPATCH()

#undef BINARY_OP_SPECIAL
#undef BINARY_OP_RSPECIAL
#undef PREDICT_INT_OP

    case OP_IS_OP:{
        PyVar _1 = POPX();    // rhs
        PyVar _0 = TOP();     // lhs
        TOP() = _0 == _1 ? True : False;
    } DISPATCH()
    case OP_IS_NOT_OP:{
        PyVar _1 = POPX();    // rhs
        PyVar _0 = TOP();     // lhs
        TOP() = _0 != _1 ? True : False;
    } DISPATCH()
    case OP_CONTAINS_OP:{
        // a in b -> b __contains__ a
        auto _ti = _tp_info(TOP());
        PyVar _0;
        if(_ti->m__contains__){
            _0 = _ti->m__contains__(this, TOP(), SECOND());
        }else{
            _0 = call_method(TOP(), __contains__, SECOND());
        }
        POP();
        TOP() = VAR(static_cast<bool>((int)CAST(bool, _0) ^ byte.arg));
    } DISPATCH()
    /*****************************************/
    case OP_JUMP_FORWARD:
        DISPATCH_JUMP((int16_t)byte.arg)
    case OP_POP_JUMP_IF_FALSE:
        if(!py_bool(POPX())) DISPATCH_JUMP((int16_t)byte.arg)
        DISPATCH()
    case OP_POP_JUMP_IF_TRUE:
        if(py_bool(POPX())) DISPATCH_JUMP((int16_t)byte.arg)
        DISPATCH()
    case OP_JUMP_IF_TRUE_OR_POP:
        if(py_bool(TOP())){
            DISPATCH_JUMP((int16_t)byte.arg)
        }else{
            POP();
            DISPATCH()
        }
    case OP_JUMP_IF_FALSE_OR_POP:
        if(!py_bool(TOP())){
            DISPATCH_JUMP((int16_t)byte.arg)
        }else{
            POP();
            DISPATCH()
        }
    case OP_SHORTCUT_IF_FALSE_OR_POP:
        if(!py_bool(TOP())){                // [b, False]
            STACK_SHRINK(2);                // []
            PUSH(vm->False);                // [False]
            DISPATCH_JUMP((int16_t)byte.arg)
        } else{
            POP();                          // [b]
            DISPATCH()
        }
    case OP_LOOP_CONTINUE:
        // just an alias of OP_JUMP_FORWARD
        DISPATCH_JUMP((int16_t)byte.arg)
    case OP_LOOP_BREAK: {
        frame->prepare_jump_break(&s_data, frame->ip()+byte.arg);
        DISPATCH_JUMP((int16_t)byte.arg)
    }
    case OP_JUMP_ABSOLUTE_TOP:
        DISPATCH_JUMP_ABSOLUTE(_CAST(int, POPX()))
    case OP_GOTO: {
        StrName _name(byte.arg);
        int target = frame->co->labels.try_get_likely_found(_name);
        if(target < 0) RuntimeError(_S("label ", _name.escape(), " not found"));
        frame->prepare_jump_break(&s_data, target);
        DISPATCH_JUMP_ABSOLUTE(target)
    }
    /*****************************************/
    case OP_FSTRING_EVAL:{
        PyVar _0 = frame->co->consts[byte.arg];
        std::string_view string = CAST(Str&, _0).sv();
        auto it = __cached_codes.find(string);
        CodeObject_ code;
        if(it == __cached_codes.end()){
            code = vm->compile(string, "<eval>", EVAL_MODE, true);
            __cached_codes[string] = code;
        }else{
            code = it->second;
        }
        _0 = vm->_exec(code.get(), frame->_module, frame->_callable, frame->_locals);
        PUSH(_0);
    } DISPATCH()
    case OP_REPR:
        TOP() = VAR(py_repr(TOP()));
        DISPATCH()
    case OP_CALL:{
        if(heap._should_auto_collect()) heap._auto_collect();
        PyVar _0 = vectorcall(
            byte.arg & 0xFF,          // ARGC
            (byte.arg>>8) & 0xFF,     // KWARGC
            true
        );
        if(_0 == PY_OP_CALL){
            frame = &callstack.top();
            goto __NEXT_FRAME;
        }
        PUSH(_0);
    } DISPATCH()
    case OP_CALL_TP:{
        if(heap._should_auto_collect()) heap._auto_collect();
        PyVar _0;
        PyVar _1;
        PyVar _2;
        // [callable, <self>, args: tuple, kwargs: dict | NULL]
        if(byte.arg){
            _2 = POPX();
            _1 = POPX();
            for(PyVar obj: _CAST(Tuple&, _1)) PUSH(obj);
            _CAST(Dict&, _2).apply([this](PyVar k, PyVar v){
                PUSH(VAR(StrName(CAST(Str&, k)).index));
                PUSH(v);
            });
            _0 = vectorcall(
                _CAST(Tuple&, _1).size(),   // ARGC
                _CAST(Dict&, _2).size(),    // KWARGC
                true
            );
        }else{
            // no **kwargs
            _1 = POPX();
            for(PyVar obj: _CAST(Tuple&, _1)) PUSH(obj);
            _0 = vectorcall(
                _CAST(Tuple&, _1).size(),   // ARGC
                0,                          // KWARGC
                true
            );
        }
        if(_0 == PY_OP_CALL){
            frame = &callstack.top();
            goto __NEXT_FRAME;
        }
        PUSH(_0);
    } DISPATCH()
    case OP_RETURN_VALUE:{
        PyVar _0 = byte.arg == BC_NOARG ? POPX() : None;
        __pop_frame();
        if(frame == base_frame){       // [ frameBase<- ]
            return _0;
        }else{
            frame = &callstack.top();
            PUSH(_0);
            goto __NEXT_FRAME;
        }
    } DISPATCH()
    case OP_YIELD_VALUE: return PY_OP_YIELD;
    /*****************************************/
    case OP_LIST_APPEND:{
        PyVar _0 = POPX();
        PK_OBJ_GET(List, SECOND()).push_back(_0);
    } DISPATCH()
    case OP_DICT_ADD: {
        PyVar _0 = POPX();
        const Tuple& t = PK_OBJ_GET(Tuple, _0);
        PK_OBJ_GET(Dict, SECOND()).set(this, t[0], t[1]);
    } DISPATCH()
    case OP_SET_ADD:{
        PyVar _0 = POPX();
        call_method(SECOND(), pk_id_add, _0);
    } DISPATCH()
    /*****************************************/
    case OP_UNARY_NEGATIVE:
        TOP() = py_negate(TOP());
        DISPATCH()
    case OP_UNARY_NOT:{
        PyVar _0 = TOP();
        if(_0==True) TOP()=False;
        else if(_0==False) TOP()=True;
        else TOP() = VAR(!py_bool(_0));
    } DISPATCH()
    case OP_UNARY_STAR:
        TOP() = VAR(StarWrapper(byte.arg, TOP()));
        DISPATCH()
    case OP_UNARY_INVERT:{
        PyVar _0;
        auto _ti = _tp_info(TOP());
        if(_ti->m__invert__) _0 = _ti->m__invert__(this, TOP());
        else _0 = call_method(TOP(), __invert__);
        TOP() = _0;
    } DISPATCH()
    /*****************************************/
    case OP_GET_ITER:
        TOP() = py_iter(TOP());
        DISPATCH()
    case OP_GET_ITER_NEW: {
        // This opcode always creates a temporary iterator object
        const PyTypeInfo* _ti = _tp_info(TOP());
        if(_ti->op__iter__){
            PyVar _0 = POPX();
            _ti->op__iter__(this, _0);
        }else{
            TOP() = py_iter(TOP());
        }
        DISPATCH()
    }
    case OP_FOR_ITER:{
        PyVar _0 = py_next(TOP());
        if(_0 == StopIteration){
            int target = frame->prepare_loop_break(&s_data);
            DISPATCH_JUMP_ABSOLUTE(target)
        } else{
            PUSH(_0);
            DISPATCH()
        }
    } 
    case OP_FOR_ITER_STORE_FAST:{
        PyVar _0 = py_next(TOP());
        if(_0 == StopIteration){
            int target = frame->prepare_loop_break(&s_data);
            DISPATCH_JUMP_ABSOLUTE(target)
        }else{
            frame->_locals[byte.arg] = _0;
            DISPATCH()
        }
    }
    case OP_FOR_ITER_STORE_GLOBAL:{
        PyVar _0 = py_next(TOP());
        if(_0 == StopIteration){
            int target = frame->prepare_loop_break(&s_data);
            DISPATCH_JUMP_ABSOLUTE(target)
        }else{
            frame->f_globals().set(StrName(byte.arg), _0);
            DISPATCH()
        }
    }
    case OP_FOR_ITER_YIELD_VALUE:{
        PyVar _0 = py_next(TOP());
        if(_0 == StopIteration){
            int target = frame->prepare_loop_break(&s_data);
            DISPATCH_JUMP_ABSOLUTE(target)
        }else{
            PUSH(_0);
            return PY_OP_YIELD;
        }
    }
    case OP_FOR_ITER_UNPACK:{
        PyVar _0 = TOP();
        const PyTypeInfo* _ti = _tp_info(_0);
        if(_ti->op__next__){
            unsigned n = _ti->op__next__(this, _0);
            if(n == 0){
                // StopIteration
                int target = frame->prepare_loop_break(&s_data);
                DISPATCH_JUMP_ABSOLUTE(target)
            }else if(n == 1){
                // UNPACK_SEQUENCE
                __op_unpack_sequence(byte.arg);
            }else{
                if(n != byte.arg){
                    ValueError(_S("expected ", (int)byte.arg, " values to unpack, got ", (int)n));
                }
            }
        }else{
            // FOR_ITER
            _0 = call_method(_0, __next__);
            if(_0 != StopIteration){
                PUSH(_0);
                // UNPACK_SEQUENCE
                __op_unpack_sequence(byte.arg);
            }else{
                int target = frame->prepare_loop_break(&s_data);
                DISPATCH_JUMP_ABSOLUTE(target)
            }
        }
    } DISPATCH()
    /*****************************************/
    case OP_IMPORT_PATH:{
        PyVar _0 = frame->co->consts[byte.arg];
        PUSH(py_import(CAST(Str&, _0)));
    } DISPATCH()
    case OP_POP_IMPORT_STAR: {
        PyVar _0 = POPX();        // pop the module
        PyVar _1 = _0->attr().try_get(__all__);
        StrName _name;
        if(_1 != nullptr){
            for(PyVar key: CAST(List&, _1)){
                _name = StrName::get(CAST(Str&, key).sv());
                PyVar value = _0->attr().try_get_likely_found(_name);
                if(value == nullptr){
                    ImportError(_S("cannot import name ", _name.escape()));
                }else{
                    frame->f_globals().set(_name, value);
                }
            }
        }else{
            for(auto& [name, value]: _0->attr().items()){
                std::string_view s = name.sv();
                if(s.empty() || s[0] == '_') continue;
                frame->f_globals().set(name, value);
            }
        }
    } DISPATCH()
    /*****************************************/
    case OP_UNPACK_SEQUENCE:{
        __op_unpack_sequence(byte.arg);
    } DISPATCH()
    case OP_UNPACK_EX: {
        auto _lock = heap.gc_scope_lock();  // lock the gc via RAII!!
        PyVar _0 = py_iter(POPX());
        const PyTypeInfo* _ti = _tp_info(_0);
        PyVar _1;
        for(int i=0; i<byte.arg; i++){
            _1 = _py_next(_ti, _0);
            if(_1 == StopIteration) ValueError("not enough values to unpack");
            PUSH(_1);
        }
        List extras;
        while(true){
            _1 = _py_next(_ti, _0);
            if(_1 == StopIteration) break;
            extras.push_back(_1);
        }
        PUSH(VAR(std::move(extras)));
    } DISPATCH()
    /*****************************************/
    case OP_BEGIN_CLASS:{
        StrName _name(byte.arg);
        PyVar _0 = POPX();   // super
        if(_0 == None) _0 = _t(tp_object);
        check_type(_0, tp_type);
        __curr_class = new_type_object(frame->_module, _name, PK_OBJ_GET(Type, _0), true);
    } DISPATCH()
    case OP_END_CLASS: {
        assert(__curr_class != nullptr);
        StrName _name(byte.arg);
        frame->_module->attr().set(_name, __curr_class);
        // call on_end_subclass
        PyTypeInfo* ti = &_all_types[__curr_class->as<Type>()];
        if(ti->base != tp_object){
            PyTypeInfo* base_ti = &_all_types[ti->base];
            if(base_ti->on_end_subclass) base_ti->on_end_subclass(this, ti);
        }
        __curr_class = nullptr;
    } DISPATCH()
    case OP_STORE_CLASS_ATTR:{
        assert(__curr_class != nullptr);
        StrName _name(byte.arg);
        PyVar _0 = POPX();
        if(is_type(_0, tp_function)){
            PK_OBJ_GET(Function, _0)._class = __curr_class;
        }
        __curr_class->attr().set(_name, _0);
    } DISPATCH()
    case OP_BEGIN_CLASS_DECORATION:{
        PUSH(__curr_class);
    } DISPATCH()
    case OP_END_CLASS_DECORATION:{
        __curr_class = POPX().get();
    } DISPATCH()
    case OP_ADD_CLASS_ANNOTATION: {
        assert(__curr_class != nullptr);
        StrName _name(byte.arg);
        Type type = __curr_class->as<Type>();
        _all_types[type].annotated_fields.push_back(_name);
    } DISPATCH()
    /*****************************************/
    case OP_WITH_ENTER:
        PUSH(call_method(TOP(), __enter__));
        DISPATCH()
    case OP_WITH_EXIT:
        call_method(TOP(), __exit__);
        POP();
        DISPATCH()
    /*****************************************/
    case OP_TRY_ENTER: {
        frame->set_unwind_target(s_data._sp);
        DISPATCH()
    }
    case OP_EXCEPTION_MATCH: {
        PyVar assumed_type = POPX();
        check_type(assumed_type, tp_type);
        PyVar e_obj = TOP();
        bool ok = isinstance(e_obj, PK_OBJ_GET(Type, assumed_type));
        PUSH(VAR(ok));
    } DISPATCH()
    case OP_RAISE: {
        if(is_type(TOP(), tp_type)){
            TOP() = call(TOP());
        }
        if(!isinstance(TOP(), tp_exception)){
            TypeError("exceptions must derive from Exception");
        }
        _error(POPX());
    } DISPATCH()
    case OP_RAISE_ASSERT:
        if(byte.arg){
            Str msg = py_str(TOP());
            POP();
            AssertionError(msg);
        }else{
            AssertionError();
        }
        DISPATCH()
    case OP_RE_RAISE: __raise_exc(true); DISPATCH()
    case OP_POP_EXCEPTION: __last_exception = POPX().get(); DISPATCH()
    /*****************************************/
    case OP_FORMAT_STRING: {
        PyVar _0 = POPX();
        const Str& spec = CAST(Str&, frame->co->consts[byte.arg]);
        PUSH(__format_object(_0, spec));
    } DISPATCH()
    /*****************************************/
    case OP_INC_FAST:{
        PyVar* p = &frame->_locals[byte.arg];
        if(*p == PY_NULL) vm->NameError(frame->co->varnames[byte.arg]);
        *p = VAR(CAST(i64, *p) + 1);
    } DISPATCH()
    case OP_DEC_FAST:{
        PyVar* p = &frame->_locals[byte.arg];
        if(*p == PY_NULL) vm->NameError(frame->co->varnames[byte.arg]);
        *p = VAR(CAST(i64, *p) - 1);
    } DISPATCH()
    case OP_INC_GLOBAL:{
        StrName _name(byte.arg);
        PyVar* p = frame->f_globals().try_get_2_likely_found(_name);
        if(p == nullptr) vm->NameError(_name);
        *p = VAR(CAST(i64, *p) + 1);
    } DISPATCH()
    case OP_DEC_GLOBAL:{
        StrName _name(byte.arg);
        PyVar* p = frame->f_globals().try_get_2_likely_found(_name);
        if(p == nullptr) vm->NameError(_name);
        *p = VAR(CAST(i64, *p) - 1);
    } DISPATCH()
    /*****************************************/
    default: PK_UNREACHABLE();
    }
}
/**********************************************************************/
            PK_UNREACHABLE();
        }catch(InternalException internal){
            __internal_exception = internal;
            if(internal.type == InternalExceptionType::Unhandled){
                __last_exception = POPX().get();
                Exception& _e = __last_exception->as<Exception>();
                bool is_base_frame_to_be_popped = frame == base_frame;
                __pop_frame();
                if(callstack.empty()){
                    // propagate to the top level
                    throw TopLevelException(this, &_e);
                }
                frame = &callstack.top();
                PUSH(__last_exception);
                if(is_base_frame_to_be_popped){
                    throw InternalException(InternalExceptionType::ToBeRaised);
                }
            }
        }
    }
}

#undef TOP
#undef SECOND
#undef THIRD
#undef STACK_SHRINK
#undef PUSH
#undef POP
#undef POPX
#undef STACK_VIEW

#undef DISPATCH
#undef DISPATCH_JUMP
#undef CEVAL_STEP_CALLBACK

} // namespace pkpy