Get entry frame shim working.

Author: markshannon

Include/internal/pycore_code.h

@@ -510,6 +510,9 @@ _PyCode_LineNumberFromArray(PyCodeObject *co, int index)
     }
 }
 
+extern PyCodeObject *
+_Py_MakeTrampoline(const char *code, int codelen, const char *cname);
+
 
 #ifdef __cplusplus
 }

Include/internal/pycore_frame.h

@@ -42,7 +42,8 @@ typedef enum _framestate {
 enum _frameowner {
     FRAME_OWNED_BY_THREAD = 0,
     FRAME_OWNED_BY_GENERATOR = 1,
-    FRAME_OWNED_BY_FRAME_OBJECT = 2
+    FRAME_OWNED_BY_FRAME_OBJECT = 2,
+    FRAME_OWNED_BY_CSTACK = 3,
 };
 
 typedef struct _PyInterpreterFrame {
@@ -60,9 +61,9 @@ typedef struct _PyInterpreterFrame {
     // example, it may be an inline CACHE entry, an instruction we just jumped
     // over, or (in the case of a newly-created frame) a totally invalid value:
     _Py_CODEUNIT *prev_instr;
-    int stacktop;     /* Offset of TOS from localsplus  */
-    bool is_entry;  // Whether this is the "root" frame for the current _PyCFrame.
-    char owner;
+    int stacktop;  /* Offset of TOS from localsplus  */
+    int yield_offset: 28;
+    int owner: 4;
     /* Locals and stack */
     PyObject *localsplus[1];
 } _PyInterpreterFrame;
@@ -109,7 +110,6 @@ _PyFrame_InitializeSpecials(
     frame->stacktop = code->co_nlocalsplus;
     frame->frame_obj = NULL;
     frame->prev_instr = _PyCode_CODE(code) - 1;
-    frame->is_entry = false;
     frame->owner = FRAME_OWNED_BY_THREAD;
 }
 

Include/internal/pycore_interp.h

@@ -175,6 +175,7 @@ struct _is {
     struct ast_state ast;
     struct types_state types;
     struct callable_cache callable_cache;
+    PyCodeObject *interpreter_trampoline;
 
     /* The following fields are here to avoid allocation during init.
        The data is exposed through PyInterpreterState pointer fields.

Include/internal/pycore_opcode.h

@@ -77,7 +77,7 @@ def pseudo_op(name, op, real_ops):
 def_op('CACHE', 0)
 def_op('POP_TOP', 1)
 def_op('PUSH_NULL', 2)
-def_op('INTEPRETER_EXIT', 3)
+def_op('INTERPRETER_EXIT', 3)
 
 def_op('NOP', 9)
 def_op('UNARY_POSITIVE', 10)

Include/opcode.h

@@ -411,6 +411,9 @@ traceback_get_frames(traceback_t *traceback)
         }
 
         _PyInterpreterFrame *back = pyframe->previous;
+        if (back && back->owner == FRAME_OWNED_BY_CSTACK) {
+            back = back->previous;
+        }
         pyframe = back;
     }
 }

Lib/opcode.py

@@ -2221,3 +2221,57 @@ _PyStaticCode_InternStrings(PyCodeObject *co)
     }
     return 0;
 }
+
+PyCodeObject *
+_Py_MakeTrampoline(const char *code, int codelen, const char *cname)
+{
+    PyObject *name = NULL;
+    PyObject *co_code = NULL;
+    PyObject *lines = NULL;
+    PyCodeObject *codeobj = NULL;
+
+    name = _PyUnicode_FromASCII(cname, strlen(cname));
+    if (name == NULL) {
+        goto cleanup;
+    }
+    co_code = PyBytes_FromStringAndSize(code, codelen);
+    if (co_code == NULL) {
+        goto cleanup;
+    }
+    const char loc[2] = { 0x80 | (PY_CODE_LOCATION_INFO_NO_COLUMNS << 3) | 3, 0 };
+    lines = PyBytes_FromStringAndSize(loc, 2);
+    if (lines == NULL) {
+        goto cleanup;
+    }
+    struct _PyCodeConstructor con = {
+        .filename = &_Py_STR(empty),
+        .name = name,
+        .qualname = name,
+        .flags = CO_NEWLOCALS | CO_OPTIMIZED,
+
+        .code = co_code,
+        .firstlineno = 1,
+        .linetable = lines,
+
+        .consts = (PyObject *)&_Py_SINGLETON(tuple_empty),
+        .names = (PyObject *)&_Py_SINGLETON(tuple_empty),
+
+        .localsplusnames = (PyObject *)&_Py_SINGLETON(tuple_empty),
+        .localspluskinds = (PyObject *)&_Py_SINGLETON(bytes_empty),
+
+        .argcount = 0,
+        .posonlyargcount = 0,
+        .kwonlyargcount = 0,
+
+        .stacksize = 2,
+
+        .exceptiontable = (PyObject *)&_Py_SINGLETON(bytes_empty),
+    };
+
+    codeobj = _PyCode_New(&con);
+cleanup:
+    Py_XDECREF(name);
+    Py_XDECREF(co_code);
+    Py_XDECREF(lines);
+    return codeobj;
+}

Modules/_tracemalloc.c

@@ -1339,14 +1339,18 @@ PyFrame_LocalsToFast(PyFrameObject *f, int clear)
     }
 }
 
-
 int _PyFrame_IsEntryFrame(PyFrameObject *frame)
 {
     assert(frame != NULL);
-    return frame->f_frame->is_entry;
+    _PyInterpreterFrame *f = frame->f_frame;
+    assert(f->owner == FRAME_OWNED_BY_FRAME_OBJECT ||
+           f->owner == FRAME_OWNED_BY_GENERATOR);
+    if (f->previous == NULL) {
+        return 0;
+    }
+    return f->previous->owner == FRAME_OWNED_BY_CSTACK;
 }
 
-
 PyCodeObject *
 PyFrame_GetCode(PyFrameObject *frame)
 {

Objects/codeobject.c

@@ -208,6 +208,7 @@ gen_send_ex2(PyGenObject *gen, PyObject *arg, PyObject **presult,
     Py_INCREF(result);
     _PyFrame_StackPush(frame, result);
 
+    _PyInterpreterFrame *prev = tstate->cframe->current_frame;
     frame->previous = tstate->cframe->current_frame;
 
     gen->gi_exc_state.previous_item = tstate->exc_info;
@@ -227,7 +228,7 @@ gen_send_ex2(PyGenObject *gen, PyObject *arg, PyObject **presult,
     tstate->exc_info = gen->gi_exc_state.previous_item;
     gen->gi_exc_state.previous_item = NULL;
 
-    assert(tstate->cframe->current_frame == frame->previous);
+    assert(tstate->cframe->current_frame == prev);
     /* Don't keep the reference to previous any longer than necessary.  It
      * may keep a chain of frames alive or it could create a reference
      * cycle. */
@@ -273,7 +274,6 @@ gen_send_ex2(PyGenObject *gen, PyObject *arg, PyObject **presult,
     _PyErr_ClearExcState(&gen->gi_exc_state);
 
     gen->gi_frame_state = FRAME_CLEARED;
-    _PyFrame_Clear(frame);
     *presult = result;
     return result ? PYGEN_RETURN : PYGEN_ERROR;
 }