[3.11] gh-93382: Cache result of `PyCode_GetCode` in codeobject (GH-93383) (#93493)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Dennis Sweeney <36520290+sweeneyde@users.noreply.github.com>

Include/cpython/code.h

@@ -89,6 +89,7 @@ typedef uint16_t _Py_CODEUNIT;
     PyObject *co_qualname;        /* unicode (qualname, for reference) */      \
     PyObject *co_linetable;       /* bytes object that holds location info */  \
     PyObject *co_weakreflist;     /* to support weakrefs to code objects */    \
+    PyObject *_co_code;           /* cached co_code object/attribute */        \
     char *_co_linearray;          /* array of line offsets */                  \
     /* Scratch space for extra data relating to the code object.               \
        Type is a void* to keep the format private in codeobject.c to force     \

Misc/NEWS.d/next/Core and Builtins/2022-05-31-16-36-30.gh-issue-93382.Jf6gAj.rst

@@ -0,0 +1,2 @@
+Cache the result of :c:func:`PyCode_GetCode` function to restore the O(1)
+lookup of the :attr:`~types.CodeType.co_code` attribute.

Objects/codeobject.c

@@ -334,6 +334,7 @@ init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
     /* not set */
     co->co_weakreflist = NULL;
     co->co_extra = NULL;
+    co->_co_code = NULL;
 
     co->co_warmup = QUICKENING_INITIAL_WARMUP_VALUE;
     co->_co_linearray_entry_size = 0;
@@ -1421,12 +1422,17 @@ deopt_code(_Py_CODEUNIT *instructions, Py_ssize_t len)
 PyObject *
 _PyCode_GetCode(PyCodeObject *co)
 {
+    if (co->_co_code != NULL) {
+        return Py_NewRef(co->_co_code);
+    }
     PyObject *code = PyBytes_FromStringAndSize((const char *)_PyCode_CODE(co),
                                                _PyCode_NBYTES(co));
     if (code == NULL) {
         return NULL;
     }
     deopt_code((_Py_CODEUNIT *)PyBytes_AS_STRING(code), Py_SIZE(co));
+    assert(co->_co_code == NULL);
+    co->_co_code = Py_NewRef(code);
     return code;
 }
 
@@ -1585,6 +1591,7 @@ code_dealloc(PyCodeObject *co)
     Py_XDECREF(co->co_qualname);
     Py_XDECREF(co->co_linetable);
     Py_XDECREF(co->co_exceptiontable);
+    Py_XDECREF(co->_co_code);
     if (co->co_weakreflist != NULL) {
         PyObject_ClearWeakRefs((PyObject*)co);
     }
@@ -2142,6 +2149,7 @@ _PyStaticCode_Dealloc(PyCodeObject *co)
     deopt_code(_PyCode_CODE(co), Py_SIZE(co));
     co->co_warmup = QUICKENING_INITIAL_WARMUP_VALUE;
     PyMem_Free(co->co_extra);
+    Py_CLEAR(co->_co_code);
     co->co_extra = NULL;
     if (co->co_weakreflist != NULL) {
         PyObject_ClearWeakRefs((PyObject *)co);

Programs/test_frozenmain.h

@@ -1,7 +1,7 @@
 // Auto-generated by Programs/freeze_test_frozenmain.py
 unsigned char M_test_frozenmain[] = {
     227,0,0,0,0,0,0,0,0,0,0,0,0,8,0,0,
-    0,0,0,0,0,115,176,0,0,0,151,0,100,0,100,1,
+    0,0,0,0,0,243,176,0,0,0,151,0,100,0,100,1,
     108,0,90,0,100,0,100,1,108,1,90,1,2,0,101,2,
     100,2,166,1,0,0,171,1,0,0,0,0,0,0,0,0,
     1,0,2,0,101,2,100,3,101,0,106,3,0,0,0,0,
@@ -24,10 +24,10 @@ unsigned char M_test_frozenmain[] = {
     32,122,2,58,32,41,7,218,3,115,121,115,218,17,95,116,
     101,115,116,105,110,116,101,114,110,97,108,99,97,112,105,218,
     5,112,114,105,110,116,218,4,97,114,103,118,218,11,103,101,
-    116,95,99,111,110,102,105,103,115,114,2,0,0,0,218,3,
+    116,95,99,111,110,102,105,103,115,114,3,0,0,0,218,3,
     107,101,121,169,0,243,0,0,0,0,250,18,116,101,115,116,
     95,102,114,111,122,101,110,109,97,105,110,46,112,121,250,8,
-    60,109,111,100,117,108,101,62,114,17,0,0,0,1,0,0,
+    60,109,111,100,117,108,101,62,114,18,0,0,0,1,0,0,
     0,115,152,0,0,0,248,240,6,0,1,11,128,10,128,10,
     128,10,216,0,24,208,0,24,208,0,24,208,0,24,224,0,
     5,128,5,208,6,26,209,0,27,212,0,27,208,0,27,216,
@@ -37,6 +37,6 @@ unsigned char M_test_frozenmain[] = {
     7,1,42,240,0,7,1,42,128,67,240,14,0,5,10,128,
     69,208,10,40,144,67,208,10,40,208,10,40,152,54,160,35,
     156,59,208,10,40,208,10,40,209,4,41,212,4,41,208,4,
-    41,208,4,41,240,15,7,1,42,240,0,7,1,42,114,15,
+    41,208,4,41,240,15,7,1,42,240,0,7,1,42,114,16,
     0,0,0,
 };

Tools/scripts/deepfreeze.py

@@ -279,6 +279,7 @@ class Printer:
             self.write(f".co_name = {co_name},")
             self.write(f".co_qualname = {co_qualname},")
             self.write(f".co_linetable = {co_linetable},")
+            self.write(f"._co_code = NULL,")
             self.write("._co_linearray = NULL,")
             self.write(f".co_code_adaptive = {co_code_adaptive},")
         name_as_code = f"(PyCodeObject *)&{name}"