bpo-43693: Add _PyCode_New(). (gh-26375)

This is an internal-only API that helps us manage the many values used to create a code object.

https://bugs.python.org/issue43693

Python/compile.c

@@ -24,6 +24,7 @@
 #include "Python.h"
 #include "pycore_ast.h"           // _PyAST_GetDocString()
 #include "pycore_compile.h"       // _PyFuture_FromAST()
+#include "pycore_code.h"          // _PyCode_New()
 #include "pycore_pymem.h"         // _PyMem_IsPtrFreed()
 #include "pycore_long.h"          // _PyLong_GetZero()
 #include "pycore_symtable.h"      // PySTEntryObject
@@ -7166,16 +7167,16 @@ merge_const_one(struct compiler *c, PyObject **obj)
 }
 
 static PyCodeObject *
-makecode(struct compiler *c, struct assembler *a, PyObject *consts, int maxdepth)
+makecode(struct compiler *c, struct assembler *a, PyObject *constslist,
+         int maxdepth)
 {
     PyCodeObject *co = NULL;
     PyObject *names = NULL;
+    PyObject *consts = NULL;
     PyObject *varnames = NULL;
     PyObject *name = NULL;
     PyObject *freevars = NULL;
     PyObject *cellvars = NULL;
-    Py_ssize_t nlocals;
-    int nlocals_int;
     int flags;
     int posorkeywordargcount, posonlyargcount, kwonlyargcount;
 
@@ -7199,34 +7200,53 @@ makecode(struct compiler *c, struct assembler *a, PyObject *consts, int maxdepth
         goto error;
     }
 
-    nlocals = PyDict_GET_SIZE(c->u->u_varnames);
-    assert(nlocals < INT_MAX);
-    nlocals_int = Py_SAFE_DOWNCAST(nlocals, Py_ssize_t, int);
-
     flags = compute_code_flags(c);
     if (flags < 0)
         goto error;
 
-    consts = PyList_AsTuple(consts); /* PyCode_New requires a tuple */
+    consts = PyList_AsTuple(constslist); /* PyCode_New requires a tuple */
     if (consts == NULL) {
         goto error;
     }
     if (!merge_const_one(c, &consts)) {
-        Py_DECREF(consts);
         goto error;
     }
 
     posonlyargcount = Py_SAFE_DOWNCAST(c->u->u_posonlyargcount, Py_ssize_t, int);
     posorkeywordargcount = Py_SAFE_DOWNCAST(c->u->u_argcount, Py_ssize_t, int);
     kwonlyargcount = Py_SAFE_DOWNCAST(c->u->u_kwonlyargcount, Py_ssize_t, int);
-    co = PyCode_NewWithPosOnlyArgs(posonlyargcount+posorkeywordargcount,
-                                   posonlyargcount, kwonlyargcount, nlocals_int,
-                                   maxdepth, flags, a->a_bytecode, consts, names,
-                                   varnames, freevars, cellvars, c->c_filename,
-                                   c->u->u_name, c->u->u_firstlineno, a->a_lnotab, a->a_except_table);
-    Py_DECREF(consts);
+    struct _PyCodeConstructor con = {
+        .filename = c->c_filename,
+        .name = c->u->u_name,
+        .flags = flags,
+
+        .code = a->a_bytecode,
+        .firstlineno = c->u->u_firstlineno,
+        .linetable = a->a_lnotab,
+
+        .consts = consts,
+        .names = names,
+
+        .varnames = varnames,
+        .cellvars = cellvars,
+        .freevars = freevars,
+
+        .argcount = posonlyargcount + posorkeywordargcount,
+        .posonlyargcount = posonlyargcount,
+        .kwonlyargcount = kwonlyargcount,
+
+        .stacksize = maxdepth,
+
+        .exceptiontable = a->a_except_table,
+    };
+    if (_PyCode_Validate(&con) < 0) {
+        goto error;
+    }
+    co = _PyCode_New(&con);
+
  error:
     Py_XDECREF(names);
+    Py_XDECREF(consts);
     Py_XDECREF(varnames);
     Py_XDECREF(name);
     Py_XDECREF(freevars);

Python/frozen_hello.h

@@ -1,12 +1,12 @@
 /* Auto-generated by Programs/_freeze_importlib.c */
 const unsigned char _Py_M__hello[] = {
-    99,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-    0,2,0,0,0,64,0,0,0,115,16,0,0,0,100,0,
-    90,0,101,1,100,1,131,1,1,0,100,2,83,0,41,3,
-    84,122,12,72,101,108,108,111,32,119,111,114,108,100,33,78,
-    41,2,90,11,105,110,105,116,105,97,108,105,122,101,100,218,
-    5,112,114,105,110,116,169,0,114,1,0,0,0,114,1,0,
-    0,0,122,14,60,102,114,111,122,101,110,32,104,101,108,108,
-    111,62,218,8,60,109,111,100,117,108,101,62,1,0,0,0,
-    115,4,0,0,0,4,0,12,1,243,0,0,0,0,
+    99,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,
+    0,64,0,0,0,115,16,0,0,0,100,0,90,0,101,1,
+    100,1,131,1,1,0,100,2,83,0,41,3,84,122,12,72,
+    101,108,108,111,32,119,111,114,108,100,33,78,41,2,90,11,
+    105,110,105,116,105,97,108,105,122,101,100,218,5,112,114,105,
+    110,116,169,0,114,1,0,0,0,114,1,0,0,0,122,14,
+    60,102,114,111,122,101,110,32,104,101,108,108,111,62,218,8,
+    60,109,111,100,117,108,101,62,1,0,0,0,115,4,0,0,
+    0,4,0,12,1,243,0,0,0,0,
 };

Python/marshal.c

@@ -13,6 +13,7 @@
 #include "code.h"
 #include "marshal.h"
 #include "pycore_hashtable.h"
+#include "pycore_code.h"        // _PyCode_New()
 
 /*[clinic input]
 module marshal
@@ -512,7 +513,6 @@ w_complex_object(PyObject *v, char flag, WFILE *p)
         w_long(co->co_argcount, p);
         w_long(co->co_posonlyargcount, p);
         w_long(co->co_kwonlyargcount, p);
-        w_long(co->co_nlocals, p);
         w_long(co->co_stacksize, p);
         w_long(co->co_flags, p);
         w_object(co->co_code, p);
@@ -1301,7 +1301,6 @@ r_object(RFILE *p)
             int argcount;
             int posonlyargcount;
             int kwonlyargcount;
-            int nlocals;
             int stacksize;
             int flags;
             PyObject *code = NULL;
@@ -1331,9 +1330,6 @@ r_object(RFILE *p)
                 goto code_error;
             }
             kwonlyargcount = (int)r_long(p);
-            if (PyErr_Occurred())
-                goto code_error;
-            nlocals = (int)r_long(p);
             if (PyErr_Occurred())
                 goto code_error;
             stacksize = (int)r_long(p);
@@ -1354,6 +1350,7 @@ r_object(RFILE *p)
             varnames = r_object(p);
             if (varnames == NULL)
                 goto code_error;
+            Py_ssize_t nlocals = PyTuple_GET_SIZE(varnames);
             freevars = r_object(p);
             if (freevars == NULL)
                 goto code_error;
@@ -1376,19 +1373,43 @@ r_object(RFILE *p)
             if (exceptiontable == NULL)
                 goto code_error;
 
-
             if (PySys_Audit("code.__new__", "OOOiiiiii",
                             code, filename, name, argcount, posonlyargcount,
                             kwonlyargcount, nlocals, stacksize, flags) < 0) {
                 goto code_error;
             }
 
-            v = (PyObject *) PyCode_NewWithPosOnlyArgs(
-                            argcount, posonlyargcount, kwonlyargcount,
-                            nlocals, stacksize, flags,
-                            code, consts, names, varnames,
-                            freevars, cellvars, filename, name,
-                            firstlineno, linetable, exceptiontable);
+            struct _PyCodeConstructor con = {
+                .filename = filename,
+                .name = name,
+                .flags = flags,
+
+                .code = code,
+                .firstlineno = firstlineno,
+                .linetable = linetable,
+
+                .consts = consts,
+                .names = names,
+
+                .varnames = varnames,
+                .cellvars = cellvars,
+                .freevars = freevars,
+
+                .argcount = argcount,
+                .posonlyargcount = posonlyargcount,
+                .kwonlyargcount = kwonlyargcount,
+
+                .stacksize = stacksize,
+
+                .exceptiontable = exceptiontable,
+            };
+            if (_PyCode_Validate(&con) < 0) {
+                goto code_error;
+            }
+            v = (PyObject *)_PyCode_New(&con);
+            if (v == NULL) {
+                goto code_error;
+            }
             v = r_ref_insert(v, idx, flag, p);
 
           code_error: