pythongh-123358: Update LOAD_DEREF to use stackref and atomic incref

corona10 · Sep 25, 2024 · d9e018c · d9e018c
1 parent 54dd77f
commit d9e018c
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Showing 6 changed files with 34 additions and 11 deletions.
diff --git a/Include/internal/pycore_cell.h b/Include/internal/pycore_cell.h
@@ -2,6 +2,7 @@
 #define Py_INTERNAL_CELL_H
 
 #include "pycore_critical_section.h"
+#include "pycore_object.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -42,6 +43,31 @@ PyCell_GetRef(PyCellObject *cell)
     return res;
 }
 
+static inline void
+_PyCell_GetStackRef(PyCellObject *cell, _PyStackRef *value_addr)
+{
+    PyObject *value;
+#ifdef Py_GIL_DISABLED
+    value = _Py_atomic_load_ptr(&cell->ob_ref);
+    if (value != NULL) {
+        if (_Py_IsImmortal(value) || _PyObject_HasDeferredRefcount(value)) {
+            *value_addr = (_PyStackRef){ .bits = (uintptr_t)value | Py_TAG_DEFERRED };
+            return;
+        }
+        if (_Py_TryIncrefCompare(&cell->ob_ref, value)) {
+            *value_addr = _PyStackRef_FromPyObjectSteal(value);
+            return;
+        }
+    }
+#endif
+    value = PyCell_GetRef(cell);
+    if (value == NULL) {
+        *value_addr = PyStackRef_NULL;
+        return;
+    }
+    *value_addr = PyStackRef_FromPyObjectSteal(value);
+}
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/Include/internal/pycore_opcode_metadata.h b/Include/internal/pycore_opcode_metadata.h
diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
diff --git a/Python/bytecodes.c b/Python/bytecodes.c
@@ -1649,12 +1649,11 @@ dummy_func(
 
         inst(LOAD_DEREF, ( -- value)) {
             PyCellObject *cell = (PyCellObject *)PyStackRef_AsPyObjectBorrow(GETLOCAL(oparg));
-            PyObject *value_o = PyCell_GetRef(cell);
-            if (value_o == NULL) {
+            _PyCell_GetStackRef(cell, &value);
+            if (PyStackRef_IsNull(value)) {
                 _PyEval_FormatExcUnbound(tstate, _PyFrame_GetCode(frame), oparg);
                 ERROR_IF(true, error);
             }
-            value = PyStackRef_FromPyObjectSteal(value_o);
         }
 
         inst(STORE_DEREF, (v --)) {

diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h