GH-131729: Code-gen better liveness analysis (GH-131732)

* Rename 'defined' attribute to 'in_local' to more accurately reflect how it is used

* Make death of variables explicit even for array variables.

* Convert in_memory from boolean to stack offset

* Don't apply liveness analysis to optimizer generated code

* Fix RETURN_VALUE in optimizer

1 files changed, 44 insertions, 90 deletions

diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h
index a2e6c47..493d99d 100644
--- a/Python/generated_cases.c.h
+++ b/Python/generated_cases.c.h
@@ -70,13 +70,13 @@
                 lhs = res;
                 stack_pointer[-2] = lhs;
                 PyStackRef_CLOSE(tmp);
+                tmp = rhs;
+                rhs = PyStackRef_NULL;
+                stack_pointer[-1] = rhs;
+                PyStackRef_CLOSE(tmp);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
                 stack_pointer += -1;
                 assert(WITHIN_STACK_BOUNDS());
-                _PyFrame_SetStackPointer(frame, stack_pointer);
-                PyStackRef_CLOSE(rhs);
-                stack_pointer = _PyFrame_GetStackPointer(frame);
-                stack_pointer[-1] = res;
             }
             DISPATCH();
         }
@@ -708,13 +708,13 @@
             list_st = res;
             stack_pointer[-2] = list_st;
             PyStackRef_CLOSE(tmp);
+            tmp = sub_st;
+            sub_st = PyStackRef_NULL;
+            stack_pointer[-1] = sub_st;
+            PyStackRef_CLOSE(tmp);
             stack_pointer = _PyFrame_GetStackPointer(frame);
             stack_pointer += -1;
             assert(WITHIN_STACK_BOUNDS());
-            _PyFrame_SetStackPointer(frame, stack_pointer);
-            PyStackRef_CLOSE(sub_st);
-            stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer[-1] = res;
             DISPATCH();
         }
 
@@ -834,7 +834,6 @@
             stack_pointer[-1] = tuple_st;
             PyStackRef_CLOSE(tmp);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer[-1] = res;
             DISPATCH();
         }
 
@@ -1125,11 +1124,11 @@
                 }
             }
             if (err) {
+                stack_pointer += -oparg;
+                assert(WITHIN_STACK_BOUNDS());
                 _PyFrame_SetStackPointer(frame, stack_pointer);
                 Py_DECREF(set_o);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
-                stack_pointer += -oparg;
-                assert(WITHIN_STACK_BOUNDS());
                 JUMP_TO_LABEL(error);
             }
             set = PyStackRef_FromPyObjectStealMortal(set_o);
@@ -1271,8 +1270,6 @@
             _PyStackRef *callable;
             _PyStackRef *self_or_null;
             _PyStackRef *args;
-            _PyStackRef *func;
-            _PyStackRef *maybe_self;
             _PyStackRef res;
             // _SPECIALIZE_CALL
             {
@@ -1296,17 +1293,14 @@
             // _MAYBE_EXPAND_METHOD
             {
                 args = &stack_pointer[-oparg];
-                func = &stack_pointer[-2 - oparg];
-                maybe_self = &stack_pointer[-1 - oparg];
-                args = &stack_pointer[-oparg];
                 (void)args;
                 if (PyStackRef_TYPE(callable[0]) == &PyMethod_Type && PyStackRef_IsNull(self_or_null[0])) {
                     PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                     PyObject *self = ((PyMethodObject *)callable_o)->im_self;
-                    maybe_self[0] = PyStackRef_FromPyObjectNew(self);
+                    self_or_null[0] = PyStackRef_FromPyObjectNew(self);
                     PyObject *method = ((PyMethodObject *)callable_o)->im_func;
                     _PyStackRef temp = callable[0];
-                    func[0] = PyStackRef_FromPyObjectNew(method);
+                    callable[0] = PyStackRef_FromPyObjectNew(method);
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(temp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
@@ -1315,8 +1309,6 @@
             // _DO_CALL
             {
                 args = &stack_pointer[-oparg];
-                self_or_null = &stack_pointer[-1 - oparg];
-                callable = &stack_pointer[-2 - oparg];
                 PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                 // oparg counts all of the args, but *not* self:
                 int total_args = oparg;
@@ -1458,7 +1450,7 @@
             INSTRUCTION_STATS(CALL_ALLOC_AND_ENTER_INIT);
             static_assert(INLINE_CACHE_ENTRIES_CALL == 3, "incorrect cache size");
             _PyStackRef *callable;
-            _PyStackRef *null;
+            _PyStackRef *self_or_null;
             _PyStackRef *args;
             _PyStackRef *init;
             _PyStackRef *self;
@@ -1476,15 +1468,12 @@
             // _CHECK_AND_ALLOCATE_OBJECT
             {
                 args = &stack_pointer[-oparg];
-                null = &stack_pointer[-1 - oparg];
+                self_or_null = &stack_pointer[-1 - oparg];
                 callable = &stack_pointer[-2 - oparg];
-                init = &stack_pointer[-2 - oparg];
-                self = &stack_pointer[-1 - oparg];
-                args = &stack_pointer[-oparg];
                 uint32_t type_version = read_u32(&this_instr[2].cache);
                 (void)args;
                 PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
-                if (!PyStackRef_IsNull(null[0])) {
+                if (!PyStackRef_IsNull(self_or_null[0])) {
                     UPDATE_MISS_STATS(CALL);
                     assert(_PyOpcode_Deopt[opcode] == (CALL));
                     JUMP_TO_PREDICTED(CALL);
@@ -1518,18 +1507,17 @@
                 if (self_o == NULL) {
                     JUMP_TO_LABEL(error);
                 }
-                self[0] = PyStackRef_FromPyObjectSteal(self_o);
+                self_or_null[0] = PyStackRef_FromPyObjectSteal(self_o);
                 _PyStackRef temp = callable[0];
-                init[0] = PyStackRef_FromPyObjectNew(init_func);
+                callable[0] = PyStackRef_FromPyObjectNew(init_func);
                 _PyFrame_SetStackPointer(frame, stack_pointer);
                 PyStackRef_CLOSE(temp);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
             }
             // _CREATE_INIT_FRAME
             {
-                args = &stack_pointer[-oparg];
-                self = &stack_pointer[-1 - oparg];
-                init = &stack_pointer[-2 - oparg];
+                self = self_or_null;
+                init = callable;
                 _PyFrame_SetStackPointer(frame, stack_pointer);
                 _PyInterpreterFrame *shim = _PyFrame_PushTrampolineUnchecked(
                     tstate, (PyCodeObject *)&_Py_InitCleanup, 1, frame);
@@ -2547,7 +2535,7 @@
             next_instr += 4;
             INSTRUCTION_STATS(CALL_ISINSTANCE);
             static_assert(INLINE_CACHE_ENTRIES_CALL == 3, "incorrect cache size");
-            _PyStackRef *callable;
+            _PyStackRef callable;
             _PyStackRef *self_or_null;
             _PyStackRef *args;
             _PyStackRef res;
@@ -2555,9 +2543,9 @@
             /* Skip 2 cache entries */
             args = &stack_pointer[-oparg];
             self_or_null = &stack_pointer[-1 - oparg];
-            callable = &stack_pointer[-2 - oparg];
+            callable = stack_pointer[-2 - oparg];
             /* isinstance(o, o2) */
-            PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
+            PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable);
             int total_args = oparg;
             _PyStackRef *arguments = args;
             if (!PyStackRef_IsNull(self_or_null[0])) {
@@ -2587,8 +2575,9 @@
             res = retval ? PyStackRef_True : PyStackRef_False;
             assert((!PyStackRef_IsNull(res)) ^ (_PyErr_Occurred(tstate) != NULL));
             _PyFrame_SetStackPointer(frame, stack_pointer);
-            _PyStackRef tmp = callable[0];
-            callable[0] = res;
+            _PyStackRef tmp = callable;
+            callable = res;
+            stack_pointer[-2 - oparg] = callable;
             PyStackRef_CLOSE(tmp);
             for (int _i = oparg; --_i >= 0;) {
                 tmp = args[_i];
@@ -2599,7 +2588,6 @@
             self_or_null[0] = PyStackRef_NULL;
             PyStackRef_XCLOSE(tmp);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer[-2 - oparg] = res;
             stack_pointer += -1 - oparg;
             assert(WITHIN_STACK_BOUNDS());
             DISPATCH();
@@ -2622,8 +2610,6 @@
             _PyStackRef *args;
             _PyStackRef kwnames;
             _PyStackRef kwnames_in;
-            _PyStackRef *func;
-            _PyStackRef *maybe_self;
             _PyStackRef kwnames_out;
             _PyStackRef res;
             // _SPECIALIZE_CALL_KW
@@ -2649,17 +2635,14 @@
             {
                 kwnames_in = stack_pointer[-1];
                 args = &stack_pointer[-1 - oparg];
-                func = &stack_pointer[-3 - oparg];
-                maybe_self = &stack_pointer[-2 - oparg];
-                args = &stack_pointer[-1 - oparg];
                 (void)args;
                 if (PyStackRef_TYPE(callable[0]) == &PyMethod_Type && PyStackRef_IsNull(self_or_null[0])) {
                     PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                     PyObject *self = ((PyMethodObject *)callable_o)->im_self;
-                    maybe_self[0] = PyStackRef_FromPyObjectNew(self);
+                    self_or_null[0] = PyStackRef_FromPyObjectNew(self);
                     PyObject *method = ((PyMethodObject *)callable_o)->im_func;
                     _PyStackRef temp = callable[0];
-                    func[0] = PyStackRef_FromPyObjectNew(method);
+                    callable[0] = PyStackRef_FromPyObjectNew(method);
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(temp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
@@ -2670,8 +2653,6 @@
             {
                 kwnames = kwnames_out;
                 args = &stack_pointer[-1 - oparg];
-                self_or_null = &stack_pointer[-2 - oparg];
-                callable = &stack_pointer[-3 - oparg];
                 PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                 PyObject *kwnames_o = PyStackRef_AsPyObjectBorrow(kwnames);
                 // oparg counts all of the args, but *not* self:
@@ -2696,14 +2677,12 @@
                         arguments, positional_args, kwnames_o, frame
                     );
                     stack_pointer = _PyFrame_GetStackPointer(frame);
-                    stack_pointer += -1;
+                    stack_pointer += -3 - oparg;
                     assert(WITHIN_STACK_BOUNDS());
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(kwnames);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
                     // Sync stack explicitly since we leave using DISPATCH_INLINED().
-                    stack_pointer += -2 - oparg;
-                    assert(WITHIN_STACK_BOUNDS());
                     // The frame has stolen all the arguments from the stack,
                     // so there is no need to clean them up.
                     if (new_frame == NULL) {
@@ -3958,6 +3937,7 @@
             // _INIT_CALL_PY_EXACT_ARGS
             {
                 args = &stack_pointer[-oparg];
+                self_or_null = &stack_pointer[-1 - oparg];
                 int has_self = !PyStackRef_IsNull(self_or_null[0]);
                 STAT_INC(CALL, hit);
                 new_frame = _PyFrame_PushUnchecked(tstate, callable[0], oparg + has_self, frame);
@@ -6027,10 +6007,8 @@
                     stack_pointer[-1] = iterable;
                     PyStackRef_CLOSE(tmp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
-                    stack_pointer[-1] = iter;
                 }
             }
-            stack_pointer[-1] = iter;
             DISPATCH();
         }
 
@@ -6121,17 +6099,14 @@
                 args = &stack_pointer[-oparg];
                 self_or_null = &stack_pointer[-1 - oparg];
                 callable = &stack_pointer[-2 - oparg];
-                func = &stack_pointer[-2 - oparg];
-                maybe_self = &stack_pointer[-1 - oparg];
-                args = &stack_pointer[-oparg];
                 (void)args;
                 if (PyStackRef_TYPE(callable[0]) == &PyMethod_Type && PyStackRef_IsNull(self_or_null[0])) {
                     PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                     PyObject *self = ((PyMethodObject *)callable_o)->im_self;
-                    maybe_self[0] = PyStackRef_FromPyObjectNew(self);
+                    self_or_null[0] = PyStackRef_FromPyObjectNew(self);
                     PyObject *method = ((PyMethodObject *)callable_o)->im_func;
                     _PyStackRef temp = callable[0];
-                    func[0] = PyStackRef_FromPyObjectNew(method);
+                    callable[0] = PyStackRef_FromPyObjectNew(method);
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(temp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
@@ -6139,9 +6114,8 @@
             }
             // _MONITOR_CALL
             {
-                args = &stack_pointer[-oparg];
-                maybe_self = &stack_pointer[-1 - oparg];
-                func = &stack_pointer[-2 - oparg];
+                maybe_self = self_or_null;
+                func = callable;
                 int is_meth = !PyStackRef_IsNull(maybe_self[0]);
                 PyObject *function = PyStackRef_AsPyObjectBorrow(func[0]);
                 PyObject *arg0;
@@ -6506,8 +6480,6 @@
             _PyStackRef *self_or_null;
             _PyStackRef *args;
             _PyStackRef kwnames_in;
-            _PyStackRef *func;
-            _PyStackRef *maybe_self;
             _PyStackRef kwnames_out;
             _PyStackRef kwnames;
             _PyStackRef res;
@@ -6519,17 +6491,14 @@
                 args = &stack_pointer[-1 - oparg];
                 self_or_null = &stack_pointer[-2 - oparg];
                 callable = &stack_pointer[-3 - oparg];
-                func = &stack_pointer[-3 - oparg];
-                maybe_self = &stack_pointer[-2 - oparg];
-                args = &stack_pointer[-1 - oparg];
                 (void)args;
                 if (PyStackRef_TYPE(callable[0]) == &PyMethod_Type && PyStackRef_IsNull(self_or_null[0])) {
                     PyObject *callable_o = PyStackRef_AsPyObjectBorrow(callable[0]);
                     PyObject *self = ((PyMethodObject *)callable_o)->im_self;
-                    maybe_self[0] = PyStackRef_FromPyObjectNew(self);
+                    self_or_null[0] = PyStackRef_FromPyObjectNew(self);
                     PyObject *method = ((PyMethodObject *)callable_o)->im_func;
                     _PyStackRef temp = callable[0];
-                    func[0] = PyStackRef_FromPyObjectNew(method);
+                    callable[0] = PyStackRef_FromPyObjectNew(method);
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(temp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
@@ -6538,9 +6507,6 @@
             }
             // _MONITOR_CALL_KW
             {
-                args = &stack_pointer[-1 - oparg];
-                self_or_null = &stack_pointer[-2 - oparg];
-                callable = &stack_pointer[-3 - oparg];
                 int is_meth = !PyStackRef_IsNull(self_or_null[0]);
                 PyObject *arg;
                 if (is_meth) {
@@ -6591,14 +6557,12 @@
                         arguments, positional_args, kwnames_o, frame
                     );
                     stack_pointer = _PyFrame_GetStackPointer(frame);
-                    stack_pointer += -1;
+                    stack_pointer += -3 - oparg;
                     assert(WITHIN_STACK_BOUNDS());
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     PyStackRef_CLOSE(kwnames);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
                     // Sync stack explicitly since we leave using DISPATCH_INLINED().
-                    stack_pointer += -2 - oparg;
-                    assert(WITHIN_STACK_BOUNDS());
                     // The frame has stolen all the arguments from the stack,
                     // so there is no need to clean them up.
                     if (new_frame == NULL) {
@@ -7873,7 +7837,6 @@
                 stack_pointer[-1] = owner;
                 PyStackRef_CLOSE(tmp);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
-                stack_pointer[-1] = attr;
             }
             // _PUSH_NULL_CONDITIONAL
             {
@@ -7942,7 +7905,6 @@
                 stack_pointer[-1] = owner;
                 PyStackRef_CLOSE(tmp);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
-                stack_pointer[-1] = attr;
             }
             // _PUSH_NULL_CONDITIONAL
             {
@@ -8603,7 +8565,6 @@
                 stack_pointer[-1] = owner;
                 PyStackRef_CLOSE(tmp);
                 stack_pointer = _PyFrame_GetStackPointer(frame);
-                stack_pointer[-1] = attr;
             }
             /* Skip 5 cache entries */
             // _PUSH_NULL_CONDITIONAL
@@ -9655,13 +9616,12 @@
             global_super_st = self_or_null;
             stack_pointer[-2] = global_super_st;
             PyStackRef_CLOSE(tmp);
+            tmp = class_st;
+            class_st = PyStackRef_NULL;
+            stack_pointer[-1] = class_st;
+            PyStackRef_CLOSE(tmp);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer += -1;
-            assert(WITHIN_STACK_BOUNDS());
-            _PyFrame_SetStackPointer(frame, stack_pointer);
-            PyStackRef_CLOSE(class_st);
-            stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer += -1;
+            stack_pointer += -2;
             assert(WITHIN_STACK_BOUNDS());
             attr = PyStackRef_FromPyObjectSteal(attr_o);
             stack_pointer[0] = attr;
@@ -9992,7 +9952,6 @@
                     stack_pointer[-1] = value;
                     PyStackRef_CLOSE(tmp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
-                    stack_pointer[-1] = b;
                 }
             }
             // _POP_JUMP_IF_TRUE
@@ -10036,7 +9995,6 @@
                     stack_pointer[-1] = value;
                     PyStackRef_CLOSE(tmp);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
-                    stack_pointer[-1] = b;
                 }
             }
             // _POP_JUMP_IF_FALSE
@@ -11611,7 +11569,6 @@
             stack_pointer[-1] = value;
             PyStackRef_CLOSE(tmp);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer[-1] = res;
             DISPATCH();
         }
 
@@ -11880,13 +11837,11 @@
                 *values++ = PyStackRef_FromPyObjectNew(items[i]);
             }
             UNLOCK_OBJECT(seq_o);
-            stack_pointer += -1;
+            stack_pointer += -1 + oparg;
             assert(WITHIN_STACK_BOUNDS());
             _PyFrame_SetStackPointer(frame, stack_pointer);
             PyStackRef_CLOSE(seq);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer += oparg;
-            assert(WITHIN_STACK_BOUNDS());
             DISPATCH();
         }
 
@@ -11922,13 +11877,11 @@
             for (int i = oparg; --i >= 0; ) {
                 *values++ = PyStackRef_FromPyObjectNew(items[i]);
             }
-            stack_pointer += -1;
+            stack_pointer += -1 + oparg;
             assert(WITHIN_STACK_BOUNDS());
             _PyFrame_SetStackPointer(frame, stack_pointer);
             PyStackRef_CLOSE(seq);
             stack_pointer = _PyFrame_GetStackPointer(frame);
-            stack_pointer += oparg;
-            assert(WITHIN_STACK_BOUNDS());
             DISPATCH();
         }
 
@@ -11970,6 +11923,7 @@
             _PyFrame_SetStackPointer(frame, stack_pointer);
             PyStackRef_CLOSE(seq);
             stack_pointer = _PyFrame_GetStackPointer(frame);
+            stack_pointer[-1] = val0;
             DISPATCH();
         }