init

include/pocketpy/frame.h

@@ -125,14 +125,43 @@ struct Frame {
     }
 };
 
-using CallstackContainer = small_vector_no_copy_and_move<Frame, 16>;
+struct LinkedFrame{
+    LinkedFrame* f_back;
+    Frame frame;
+    template<typename... Args>
+    LinkedFrame(LinkedFrame* f_back, Args&&... args) : f_back(f_back), frame(std::forward<Args>(args)...) {}
+};
 
-struct FrameId{
+struct CallStack{
-    CallstackContainer* data;
+    static_assert(sizeof(LinkedFrame) <= 64 && std::is_trivially_destructible_v<LinkedFrame>);
-    int index;
+
-    FrameId(CallstackContainer* data, int index) : data(data), index(index) {}
+    LinkedFrame* _tail;
-    Frame* operator->() const { return &data->operator[](index); }
+    int _size;
-    Frame* get() const { return &data->operator[](index); }
+    CallStack(): _tail(nullptr), _size(0) {}
+
+    int size() const { return _size; }
+    bool empty() const { return _size == 0; }
+    void clear(){ while(!empty()) pop(); }
+
+    template<typename... Args>
+    void emplace(Args&&... args){
+        _tail = new(pool64_alloc<LinkedFrame>()) LinkedFrame(_tail, std::forward<Args>(args)...);
+        ++_size;
+    }
+
+    void pop(){
+        LinkedFrame* p = _tail;
+        _tail = p->f_back;
+        pool64_dealloc(p);
+        --_size;
+    }
+
+    Frame& top() const { return _tail->frame; }
+
+    template<typename Func>
+    void apply(Func&& f){
+        for(LinkedFrame* p = _tail; p != nullptr; p = p->f_back) f(p->frame);
+    }
 };
 
 }; // namespace pkpy

include/pocketpy/profiler.h

@@ -14,7 +14,7 @@ struct _LineRecord{
 };
 
 struct _FrameRecord{
-    FrameId frame;
+    LinkedFrame* frame;
     clock_t prev_time;
     _LineRecord* prev_record;
 };
@@ -26,8 +26,8 @@ struct LineProfiler{
     std::set<FuncDecl*> functions;
 
     void begin();
-    void _step(FrameId frame);
+    void _step(LinkedFrame*);
-    void _step_end(FrameId frame, int line);
+    void _step_end(LinkedFrame*, int);
     void end();
     Str stats();
 };

include/pocketpy/vm.h

@@ -94,7 +94,7 @@ class VM {
 public:
     ManagedHeap heap;
     ValueStack s_data;
-    stack_no_copy<Frame, CallstackContainer> callstack;
+    CallStack callstack;
     std::vector<PyTypeInfo> _all_types;
     
     NameDict _modules;                                 // loaded modules
@@ -151,7 +151,7 @@ public:
 
     VM(bool enable_os=true);
 
-    FrameId top_frame();
+    Frame* top_frame();
     void _pop_frame();
 
     PyObject* py_str(PyObject* obj);

src/ceval.cpp

@@ -44,19 +44,12 @@ bool VM::py_ge(PyObject* _0, PyObject* _1){
 
 #undef BINARY_F_COMPARE
 
-// static i64 _py_sint(PyObject* obj) noexcept {
-//     return (i64)(PK_BITS(obj) >> 2);
-// }
-
 PyObject* VM::_run_top_frame(){
-    FrameId frame = top_frame();
+    Frame* frame = top_frame();
-    const int base_id = frame.index;
+    const Frame* base_frame = frame;
     bool need_raise = false;
 
     while(true){
-#if PK_DEBUG_EXTRA_CHECK
-        if(frame.index < base_id) PK_FATAL_ERROR();
-#endif
         try{
             if(need_raise){ need_raise = false; _raise(); }
 /**********************************************************************/
@@ -67,8 +60,8 @@ PyObject* VM::_run_top_frame(){
 {
 
 #define CEVAL_STEP_CALLBACK() \
-    if(_ceval_on_step) _ceval_on_step(this, frame.get(), byte); \
+    if(_ceval_on_step) _ceval_on_step(this, frame, byte); \
-    if(_profiler) _profiler->_step(frame);
+    if(_profiler) _profiler->_step(callstack._tail);
 
 #define DISPATCH_OP_CALL() { frame = top_frame(); goto __NEXT_FRAME; }
 __NEXT_FRAME:
@@ -598,7 +591,7 @@ __NEXT_STEP:;
     TARGET(RETURN_VALUE){
         PyObject* _0 = byte.arg == BC_NOARG ? POPX() : None;
         _pop_frame();
-        if(frame.index == base_id){       // [ frameBase<- ]
+        if(frame == base_frame){       // [ frameBase<- ]
             return _0;
         }else{
             frame = top_frame();
@@ -826,16 +819,12 @@ __NEXT_STEP:;
         }catch(UnhandledException){
             PyObject* e_obj = POPX();
             Exception& _e = PK_OBJ_GET(Exception, e_obj);
+            bool is_base_frame_to_be_popped = frame == base_frame;
             _pop_frame();
-            if(callstack.empty()){
+            if(callstack.empty()) throw _e;   // propagate to the top level
-#if PK_DEBUG_FULL_EXCEPTION
-                std::cerr << _e.summary() << std::endl;
-#endif
-                throw _e;
-            }
             frame = top_frame();
             PUSH(e_obj);
-            if(frame.index < base_id) throw ToBeRaisedException();
+            if(is_base_frame_to_be_popped) throw ToBeRaisedException();
             need_raise = true;
         }catch(ToBeRaisedException){
             need_raise = true;

src/iter.cpp

@@ -48,7 +48,7 @@ namespace pkpy{
         // restore the context
         for(PyObject* obj: s_backup) vm->s_data.push(obj);
         s_backup.clear();
-        vm->callstack.push(std::move(frame));
+        vm->callstack.emplace(std::move(frame));
 
         PyObject* ret;
         try{

src/pocketpy.cpp

@@ -77,7 +77,7 @@ void init_builtins(VM* _vm) {
             class_arg = args[0];
             self_arg = args[1];
         }else if(args.size() == 0){
-            FrameId frame = vm->top_frame();
+            Frame* frame = vm->top_frame();
             if(frame->_callable != nullptr){
                 class_arg = PK_OBJ_GET(Function, frame->_callable)._class;
                 if(frame->_locals.size() > 0) self_arg = frame->_locals[0];
@@ -184,7 +184,7 @@ void init_builtins(VM* _vm) {
         CodeObject_ code = vm->compile(CAST(Str&, args[0]), "<eval>", EVAL_MODE, true);
         PyObject* globals = args[1];
         if(globals == vm->None){
-            FrameId frame = vm->top_frame();
+            Frame* frame = vm->top_frame();
             return vm->_exec(code.get(), frame->_module, frame->_callable, frame->_locals);
         }
         vm->check_non_tagged_type(globals, vm->tp_mappingproxy);
@@ -196,7 +196,7 @@ void init_builtins(VM* _vm) {
         CodeObject_ code = vm->compile(CAST(Str&, args[0]), "<exec>", EXEC_MODE, true);
         PyObject* globals = args[1];
         if(globals == vm->None){
-            FrameId frame = vm->top_frame();
+            Frame* frame = vm->top_frame();
             vm->_exec(code.get(), frame->_module, frame->_callable, frame->_locals);
             return vm->None;
         }

src/profiler.cpp

@@ -18,16 +18,17 @@ void LineProfiler::begin(){
     frames.clear();
 }
 
-void LineProfiler::_step(FrameId frame){
+void LineProfiler::_step(LinkedFrame* linked_frame){
+    Frame* frame = &linked_frame->frame;
     auto line_info = frame->co->lines[frame->_ip];
     if(line_info.is_virtual) return;
     std::string_view filename = frame->co->src->filename.sv();
     int line = line_info.lineno;
 
     if(frames.empty()){
-        frames.push({frame, clock(), nullptr});
+        frames.push({linked_frame, clock(), nullptr});
     }else{
-        _step_end(frame, line);
+        _step_end(linked_frame, line);
     }
 
     auto& file_records = records[filename];
@@ -43,13 +44,19 @@ void LineProfiler::_step(FrameId frame){
     frames.top().prev_record = &file_records.at(line);
 }
 
-void LineProfiler::_step_end(FrameId frame, int line){
+void LineProfiler::_step_end(LinkedFrame* linked_frame, int line){
     clock_t now = clock();
     _FrameRecord& top_frame_record = frames.top();
     _LineRecord* prev_record = top_frame_record.prev_record;
 
-    int id_delta = frame.index - top_frame_record.frame.index;
+    int id_delta;
-    PK_ASSERT(id_delta >= -1 && id_delta <= 1);
+    if(linked_frame == top_frame_record.frame){
+        id_delta = 0;
+    }else if(linked_frame->f_back == top_frame_record.frame){
+        id_delta = 1;
+    }else{
+        id_delta = -1;
+    }
 
     // current line is about to change
     if(prev_record->line != line){
@@ -60,7 +67,7 @@ void LineProfiler::_step_end(FrameId frame, int line){
     }
     
     if(id_delta == 1){
-        frames.push({frame, now, nullptr});
+        frames.push({linked_frame, now, nullptr});
     }else{
         if(id_delta == -1) frames.pop();
     }

src/vm.cpp

@@ -119,16 +119,15 @@ namespace pkpy{
         PK_UNREACHABLE();
     }
 
-    FrameId VM::top_frame(){
+    Frame* VM::top_frame(){
 #if PK_DEBUG_EXTRA_CHECK
         if(callstack.empty()) PK_FATAL_ERROR();
 #endif
-        return FrameId(&callstack.container(), callstack.size()-1);
+        return &callstack.top();
     }
 
     void VM::_pop_frame(){
-        Frame* frame = &callstack.top();
+        s_data.reset(callstack.top()._sp_base);
-        s_data.reset(frame->_sp_base);
         callstack.pop();
     }
 
@@ -652,7 +651,7 @@ void VM::_log_s_data(const char* title) {
         if(f._sp_base == nullptr) PK_FATAL_ERROR();
         sp_bases[f._sp_base] += 1;
     }
-    FrameId frame = top_frame();
+    Frame* frame = top_frame();
     int line = frame->co->lines[frame->_ip];
     ss << frame->co->name << ":" << line << " [";
     for(PyObject** p=s_data.begin(); p!=s_data.end(); p++){
@@ -1238,7 +1237,7 @@ void VM::_error(PyObject* e_obj){
 }
 
 void VM::_raise(bool re_raise){
-    Frame* frame = top_frame().get();
+    Frame* frame = top_frame();
     Exception& e = PK_OBJ_GET(Exception, s_data.top());
     if(!re_raise){
         e._ip_on_error = frame->_ip;
@@ -1259,7 +1258,7 @@ void VM::_raise(bool re_raise){
 
 void ManagedHeap::mark() {
     for(PyObject* obj: _no_gc) PK_OBJ_MARK(obj);
-    for(auto& frame : vm->callstack.container()) frame._gc_mark();
+    vm->callstack.apply([](Frame& frame){ frame._gc_mark(); });
     for(PyObject* obj: vm->s_data) PK_OBJ_MARK(obj);
     for(auto [_, co]: vm->_cached_codes) co->_gc_mark();
     if(vm->_last_exception) PK_OBJ_MARK(vm->_last_exception);