GH-114695: Add sys._clear_internal_caches (GH-115152)

Python/bytecodes.c

@@ -2370,23 +2370,12 @@ dummy_func(
             CHECK_EVAL_BREAKER();
 
             PyCodeObject *code = _PyFrame_GetCode(frame);
-            _PyExecutorObject *executor = code->co_executors->executors[oparg & 255];
-            if (executor->vm_data.valid) {
-                Py_INCREF(executor);
-                current_executor = executor;
-                GOTO_TIER_TWO();
-            }
-            else {
-                /* ENTER_EXECUTOR will be the first code unit of the instruction */
-                assert(oparg < 256);
-                code->co_executors->executors[oparg] = NULL;
-                opcode = this_instr->op.code = executor->vm_data.opcode;
-                this_instr->op.arg = executor->vm_data.oparg;
-                oparg = executor->vm_data.oparg;
-                Py_DECREF(executor);
-                next_instr = this_instr;
-                DISPATCH_GOTO();
-            }
+            current_executor = code->co_executors->executors[oparg & 255];
+            assert(current_executor->vm_data.index == INSTR_OFFSET() - 1);
+            assert(current_executor->vm_data.code == code);
+            assert(current_executor->vm_data.valid);
+            Py_INCREF(current_executor);
+            GOTO_TIER_TWO();
         }
 
         replaced op(_POP_JUMP_IF_FALSE, (cond -- )) {

Python/clinic/sysmodule.c.h

@@ -1131,6 +1131,24 @@ sys__clear_type_cache(PyObject *module, PyObject *Py_UNUSED(ignored))
     return sys__clear_type_cache_impl(module);
 }
 
+PyDoc_STRVAR(sys__clear_internal_caches__doc__,
+"_clear_internal_caches($module, /)\n"
+"--\n"
+"\n"
+"Clear all internal performance-related caches.");
+
+#define SYS__CLEAR_INTERNAL_CACHES_METHODDEF    \
+    {"_clear_internal_caches", (PyCFunction)sys__clear_internal_caches, METH_NOARGS, sys__clear_internal_caches__doc__},
+
+static PyObject *
+sys__clear_internal_caches_impl(PyObject *module);
+
+static PyObject *
+sys__clear_internal_caches(PyObject *module, PyObject *Py_UNUSED(ignored))
+{
+    return sys__clear_internal_caches_impl(module);
+}
+
 PyDoc_STRVAR(sys_is_finalizing__doc__,
 "is_finalizing($module, /)\n"
 "--\n"
@@ -1486,4 +1504,4 @@ exit:
 #ifndef SYS_GETANDROIDAPILEVEL_METHODDEF
     #define SYS_GETANDROIDAPILEVEL_METHODDEF
 #endif /* !defined(SYS_GETANDROIDAPILEVEL_METHODDEF) */
-/*[clinic end generated code: output=3dc3b2cb0ce38ebb input=a9049054013a1b77]*/
+/*[clinic end generated code: output=b8b1c53e04c3b20c input=a9049054013a1b77]*/

Python/generated_cases.c.h

@@ -2363,29 +2363,18 @@
         }
 
         TARGET(ENTER_EXECUTOR) {
-            _Py_CODEUNIT *this_instr = frame->instr_ptr = next_instr;
+            frame->instr_ptr = next_instr;
             next_instr += 1;
             INSTRUCTION_STATS(ENTER_EXECUTOR);
             TIER_ONE_ONLY
             CHECK_EVAL_BREAKER();
             PyCodeObject *code = _PyFrame_GetCode(frame);
-            _PyExecutorObject *executor = code->co_executors->executors[oparg & 255];
-            if (executor->vm_data.valid) {
-                Py_INCREF(executor);
-                current_executor = executor;
-                GOTO_TIER_TWO();
-            }
-            else {
-                /* ENTER_EXECUTOR will be the first code unit of the instruction */
-                assert(oparg < 256);
-                code->co_executors->executors[oparg] = NULL;
-                opcode = this_instr->op.code = executor->vm_data.opcode;
-                this_instr->op.arg = executor->vm_data.oparg;
-                oparg = executor->vm_data.oparg;
-                Py_DECREF(executor);
-                next_instr = this_instr;
-                DISPATCH_GOTO();
-            }
+            current_executor = code->co_executors->executors[oparg & 255];
+            assert(current_executor->vm_data.index == INSTR_OFFSET() - 1);
+            assert(current_executor->vm_data.code == code);
+            assert(current_executor->vm_data.valid);
+            Py_INCREF(current_executor);
+            GOTO_TIER_TWO();
             DISPATCH();
         }
 

Python/optimizer.c

@@ -73,25 +73,21 @@ insert_executor(PyCodeObject *code, _Py_CODEUNIT *instr, int index, _PyExecutorO
     Py_INCREF(executor);
     if (instr->op.code == ENTER_EXECUTOR) {
         assert(index == instr->op.arg);
-        _PyExecutorObject *old = code->co_executors->executors[index];
-        executor->vm_data.opcode = old->vm_data.opcode;
-        executor->vm_data.oparg = old->vm_data.oparg;
-        old->vm_data.opcode = 0;
-        code->co_executors->executors[index] = executor;
-        Py_DECREF(old);
+        _Py_ExecutorClear(code->co_executors->executors[index]);
     }
     else {
         assert(code->co_executors->size == index);
         assert(code->co_executors->capacity > index);
-        executor->vm_data.opcode = instr->op.code;
-        executor->vm_data.oparg = instr->op.arg;
-        code->co_executors->executors[index] = executor;
-        assert(index < MAX_EXECUTORS_SIZE);
-        instr->op.code = ENTER_EXECUTOR;
-        instr->op.arg = index;
         code->co_executors->size++;
     }
-    return;
+    executor->vm_data.opcode = instr->op.code;
+    executor->vm_data.oparg = instr->op.arg;
+    executor->vm_data.code = code;
+    executor->vm_data.index = (int)(instr - _PyCode_CODE(code));
+    code->co_executors->executors[index] = executor;
+    assert(index < MAX_EXECUTORS_SIZE);
+    instr->op.code = ENTER_EXECUTOR;
+    instr->op.arg = index;
 }
 
 int
@@ -1071,7 +1067,7 @@ link_executor(_PyExecutorObject *executor)
         }
         head->vm_data.links.next = executor;
     }
-    executor->vm_data.linked = true;
+    executor->vm_data.valid = true;
     /* executor_list_head must be first in list */
     assert(interp->executor_list_head->vm_data.links.previous == NULL);
 }
@@ -1079,7 +1075,7 @@ link_executor(_PyExecutorObject *executor)
 static void
 unlink_executor(_PyExecutorObject *executor)
 {
-    if (!executor->vm_data.linked) {
+    if (!executor->vm_data.valid) {
         return;
     }
     _PyExecutorLinkListNode *links = &executor->vm_data.links;
@@ -1097,7 +1093,7 @@ unlink_executor(_PyExecutorObject *executor)
         assert(interp->executor_list_head == executor);
         interp->executor_list_head = next;
     }
-    executor->vm_data.linked = false;
+    executor->vm_data.valid = false;
 }
 
 /* This must be called by optimizers before using the executor */
@@ -1116,12 +1112,24 @@ void
 _Py_ExecutorClear(_PyExecutorObject *executor)
 {
     unlink_executor(executor);
+    PyCodeObject *code = executor->vm_data.code;
+    if (code == NULL) {
+        return;
+    }
+    _Py_CODEUNIT *instruction = &_PyCode_CODE(code)[executor->vm_data.index];
+    assert(instruction->op.code == ENTER_EXECUTOR);
+    int index = instruction->op.arg;
+    assert(code->co_executors->executors[index] == executor);
+    instruction->op.code = executor->vm_data.opcode;
+    instruction->op.arg = executor->vm_data.oparg;
+    executor->vm_data.code = NULL;
+    Py_CLEAR(code->co_executors->executors[index]);
 }
 
 void
 _Py_Executor_DependsOn(_PyExecutorObject *executor, void *obj)
 {
-    assert(executor->vm_data.valid = true);
+    assert(executor->vm_data.valid);
     _Py_BloomFilter_Add(&executor->vm_data.bloom, obj);
 }
 
@@ -1140,8 +1148,7 @@ _Py_Executors_InvalidateDependency(PyInterpreterState *interp, void *obj)
         assert(exec->vm_data.valid);
         _PyExecutorObject *next = exec->vm_data.links.next;
         if (bloom_filter_may_contain(&exec->vm_data.bloom, &obj_filter)) {
-            exec->vm_data.valid = false;
-            unlink_executor(exec);
+            _Py_ExecutorClear(exec);
         }
         exec = next;
     }
@@ -1151,15 +1158,14 @@ _Py_Executors_InvalidateDependency(PyInterpreterState *interp, void *obj)
 void
 _Py_Executors_InvalidateAll(PyInterpreterState *interp)
 {
-    /* Walk the list of executors */
-    for (_PyExecutorObject *exec = interp->executor_list_head; exec != NULL;) {
-        assert(exec->vm_data.valid);
-        _PyExecutorObject *next = exec->vm_data.links.next;
-        exec->vm_data.links.next = NULL;
-        exec->vm_data.links.previous = NULL;
-        exec->vm_data.valid = false;
-        exec->vm_data.linked = false;
-        exec = next;
+    while (interp->executor_list_head) {
+        _PyExecutorObject *executor = interp->executor_list_head;
+        if (executor->vm_data.code) {
+            // Clear the entire code object so its co_executors array be freed:
+            _PyCode_Clear_Executors(executor->vm_data.code);
+        }
+        else {
+            _Py_ExecutorClear(executor);
+        }
     }
-    interp->executor_list_head = NULL;
 }

Python/sysmodule.c

@@ -2127,6 +2127,22 @@ sys__clear_type_cache_impl(PyObject *module)
     Py_RETURN_NONE;
 }
 
+/*[clinic input]
+sys._clear_internal_caches
+
+Clear all internal performance-related caches.
+[clinic start generated code]*/
+
+static PyObject *
+sys__clear_internal_caches_impl(PyObject *module)
+/*[clinic end generated code: output=0ee128670a4966d6 input=253e741ca744f6e8]*/
+{
+    PyInterpreterState *interp = _PyInterpreterState_GET();
+    _Py_Executors_InvalidateAll(interp);
+    PyType_ClearCache();
+    Py_RETURN_NONE;
+}
+
 /* Note that, for now, we do not have a per-interpreter equivalent
   for sys.is_finalizing(). */
 
@@ -2461,6 +2477,7 @@ static PyMethodDef sys_methods[] = {
     {"audit", _PyCFunction_CAST(sys_audit), METH_FASTCALL, audit_doc },
     {"breakpointhook", _PyCFunction_CAST(sys_breakpointhook),
      METH_FASTCALL | METH_KEYWORDS, breakpointhook_doc},
+    SYS__CLEAR_INTERNAL_CACHES_METHODDEF
     SYS__CLEAR_TYPE_CACHE_METHODDEF
     SYS__CURRENT_FRAMES_METHODDEF
     SYS__CURRENT_EXCEPTIONS_METHODDEF