Revert "gh-133395: add option for extension modules to specialize BINARY_OP/SUBSCR, apply to arrays (#133396)"

Include/cpython/object.h

@@ -143,11 +143,6 @@ typedef struct {
  * backwards-compatibility */
 typedef Py_ssize_t printfunc;
 
-/* Specialize a binary op by setting the descriptor pointer */
-struct _PyBinopSpecializationDescr;
-typedef int (*binop_specialize_func)(PyObject *v, PyObject *w, int oparg,
-                                    struct _PyBinopSpecializationDescr **descr);
-
 // If this structure is modified, Doc/includes/typestruct.h should be updated
 // as well.
 struct _typeobject {
@@ -238,13 +233,6 @@ struct _typeobject {
     /* bitset of which type-watchers care about this type */
     unsigned char tp_watched;
 
-    /* callback that may specialize BINARY_OP
-     * this is an experimental API based on the ideas in the paper
-     * Cross Module Quickening - The Curious Case of C Extensions
-     * by Felix Berlakovich and Stefan Brunthaler.
-     */
-    binop_specialize_func tp_binop_specialize;
-
     /* Number of tp_version_tag values used.
      * Set to _Py_ATTR_CACHE_UNUSED if the attribute cache is
      * disabled for this type (e.g. due to custom MRO entries).

Include/internal/pycore_code.h

@@ -480,18 +480,13 @@ adaptive_counter_backoff(_Py_BackoffCounter counter) {
 /* Specialization Extensions */
 
 /* callbacks for an external specialization */
-
-struct _PyBinopSpecializationDescr;
-
 typedef int (*binaryopguardfunc)(PyObject *lhs, PyObject *rhs);
-typedef PyObject* (*binaryopactionfunc)(PyObject *lhs, PyObject *rhs);
-typedef void (*binaryopfreefunc)(struct _PyBinopSpecializationDescr *descr);
+typedef PyObject *(*binaryopactionfunc)(PyObject *lhs, PyObject *rhs);
 
-typedef struct _PyBinopSpecializationDescr {
+typedef struct {
     int oparg;
     binaryopguardfunc guard;
     binaryopactionfunc action;
-    binaryopfreefunc free;
 } _PyBinaryOpSpecializationDescr;
 
 /* Comparison bit masks. */

Include/typeslots.h

@@ -93,5 +93,4 @@
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030E0000
 /* New in 3.14 */
 #define Py_tp_token 83
-#define Py_tp_binop_specialize 84
 #endif

Lib/test/test_sys.py

@@ -1776,7 +1776,7 @@ def delx(self): del self.__x
         check((1,2,3), vsize('') + self.P + 3*self.P)
         # type
         # static type: PyTypeObject
-        fmt = 'P2nPI13Pl4Pn9Pn12PI3Pc'
+        fmt = 'P2nPI13Pl4Pn9Pn12PIPc'
         s = vsize(fmt)
         check(int, s)
         typeid = 'n' if support.Py_GIL_DISABLED else ''

Modules/arraymodule.c

@@ -14,8 +14,6 @@
 #include "pycore_modsupport.h"    // _PyArg_NoKeywords()
 #include "pycore_moduleobject.h"  // _PyModule_GetState()
 
-#include "opcode.h"               // binary op opargs (NB_*)
-
 #include <stddef.h>               // offsetof()
 #include <stdbool.h>
 
@@ -850,10 +848,6 @@ array_richcompare(PyObject *v, PyObject *w, int op)
     return res;
 }
 
-static int
-array_binop_specialize(PyObject *v, PyObject *w, int oparg,
-                       _PyBinaryOpSpecializationDescr **descr);
-
 static Py_ssize_t
 array_length(PyObject *op)
 {
@@ -2969,8 +2963,6 @@ static PyType_Slot array_slots[] = {
     {Py_tp_alloc, PyType_GenericAlloc},
     {Py_tp_new, array_new},
     {Py_tp_traverse, array_tp_traverse},
-    {Py_tp_token, Py_TP_USE_SPEC},
-    {Py_tp_binop_specialize, array_binop_specialize},
 
     /* as sequence */
     {Py_sq_length, array_length},
@@ -3003,70 +2995,6 @@ static PyType_Spec array_spec = {
     .slots = array_slots,
 };
 
-static inline int
-array_subscr_guard(PyObject *lhs, PyObject *rhs)
-{
-    PyObject *exc = PyErr_GetRaisedException();
-    int ret = PyType_GetBaseByToken(Py_TYPE(lhs), &array_spec, NULL);
-    if (ret < 0) {
-        if (PyErr_ExceptionMatches(PyExc_TypeError)) {
-            PyErr_Clear();
-            ret = 0;
-        }
-    }
-    _PyErr_ChainExceptions1(exc);
-    return ret;
-}
-
-static PyObject *
-array_subscr_action(PyObject *lhs, PyObject *rhs)
-{
-    return array_subscr(lhs, rhs);
-}
-
-static void
-array_subscr_free(_PyBinaryOpSpecializationDescr* descr)
-{
-    if (descr != NULL) {
-        PyMem_Free(descr);
-    }
-}
-
-static int
-array_binop_specialize(PyObject *v, PyObject *w, int oparg,
-                       _PyBinaryOpSpecializationDescr **descr)
-{
-    array_state *state = find_array_state_by_type(Py_TYPE(v));
-
-    if (!array_Check(v, state)) {
-        return 0;
-    }
-
-    *descr = NULL;
-    switch(oparg) {
-        case NB_SUBSCR:
-            if (array_subscr_guard(v, w)) {
-                *descr = (_PyBinaryOpSpecializationDescr*)PyMem_Malloc(
-                             sizeof(_PyBinaryOpSpecializationDescr));
-                if (*descr == NULL) {
-                    PyErr_NoMemory();
-                    return -1;
-                }
-                **descr = (_PyBinaryOpSpecializationDescr) {
-                    .oparg = oparg,
-                    .guard = array_subscr_guard,
-                    .action = array_subscr_action,
-                    .free = array_subscr_free,
-                };
-                return 1;
-            }
-            break;
-    }
-
-    return 0;
-}
-
-
 /*********************** Array Iterator **************************/
 
 /*[clinic input]

Python/bytecodes.c

@@ -801,19 +801,9 @@ dummy_func(
             PyObject *right_o = PyStackRef_AsPyObjectBorrow(right);
             _PyBinaryOpSpecializationDescr *d = (_PyBinaryOpSpecializationDescr*)descr;
             assert(INLINE_CACHE_ENTRIES_BINARY_OP == 5);
-            assert(d);
-            assert(d->guard);
+            assert(d && d->guard);
             int res = d->guard(left_o, right_o);
-            ERROR_IF(res < 0);
-            if (res == 0) {
-                if (d->free) {
-                    d->free(d);
-                }
-                _PyBinaryOpCache *cache = (_PyBinaryOpCache *)(this_instr+1);
-                write_ptr(cache->external_cache, NULL);
-                this_instr->op.code = BINARY_OP;
-                DEOPT_IF(true);
-            }
+            DEOPT_IF(!res);
         }
 
         pure op(_BINARY_OP_EXTEND, (descr/4, left, right -- res)) {
@@ -826,7 +816,6 @@ dummy_func(
 
             PyObject *res_o = d->action(left_o, right_o);
             DECREF_INPUTS();
-            ERROR_IF(res_o == NULL);
             res = PyStackRef_FromPyObjectSteal(res_o);
         }
 

Python/specialize.c

@@ -2534,7 +2534,7 @@ LONG_FLOAT_ACTION(compactlong_float_multiply, *)
 LONG_FLOAT_ACTION(compactlong_float_true_div, /)
 #undef LONG_FLOAT_ACTION
 
-static const _PyBinaryOpSpecializationDescr binaryop_extend_builtins[] = {
+static _PyBinaryOpSpecializationDescr binaryop_extend_descrs[] = {
     /* long-long arithmetic */
     {NB_OR, compactlongs_guard, compactlongs_or},
     {NB_AND, compactlongs_guard, compactlongs_and},
@@ -2560,41 +2560,14 @@ static int
 binary_op_extended_specialization(PyObject *lhs, PyObject *rhs, int oparg,
                                   _PyBinaryOpSpecializationDescr **descr)
 {
-    /* We are currently using this only for NB_SUBSCR, which is not
-     * commutative. Will need to revisit this function when we use
-     * this for operators which are.
-     */
-
-    typedef _PyBinaryOpSpecializationDescr descr_type;
-    size_t size = Py_ARRAY_LENGTH(binaryop_extend_builtins);
-    for (size_t i = 0; i < size; i++) {
-        descr_type *d = (descr_type *)&binaryop_extend_builtins[i];
-        assert(d != NULL);
-        assert(d->guard != NULL);
+    size_t n = sizeof(binaryop_extend_descrs)/sizeof(_PyBinaryOpSpecializationDescr);
+    for (size_t i = 0; i < n; i++) {
+        _PyBinaryOpSpecializationDescr *d = &binaryop_extend_descrs[i];
         if (d->oparg == oparg && d->guard(lhs, rhs)) {
             *descr = d;
             return 1;
         }
     }
-
-    PyTypeObject *lhs_type = Py_TYPE(lhs);
-    if (lhs_type->tp_binop_specialize != NULL) {
-        int ret = lhs_type->tp_binop_specialize(lhs, rhs, oparg, descr);
-        if (ret < 0) {
-            return -1;
-        }
-        if (ret == 1) {
-            if (*descr == NULL) {
-                PyErr_Format(
-                    PyExc_ValueError,
-                    "tp_binop_specialize of '%T' returned 1 with *descr == NULL",
-                    lhs);
-                return -1;
-            }
-            (*descr)->oparg = oparg;
-        }
-        return ret;
-    }
     return 0;
 }