also for COMPARE_OP_INT

Author: Fidget-Spinner

Include/internal/pycore_opcode_metadata.h

@@ -1646,6 +1646,7 @@ def testfunc(n):
         self.assertNotIn("_COMPARE_OP", uops)
         self.assertNotIn("_POP_TWO_LOAD_CONST_INLINE_BORROW", uops)
 
+    @unittest.skip("TODO (gh-142764): Re-enable after we get back automatic constant propagation.")
     def test_compare_op_int_pop_two_load_const_inline_borrow(self):
         def testfunc(n):
             x = 0
@@ -2065,8 +2066,9 @@ def testfunc(n):
         uops = get_opnames(ex)
         self.assertIn("_CALL_TUPLE_1", uops)
         self.assertIn("_UNPACK_SEQUENCE_TWO_TUPLE", uops)
-        self.assertNotIn("_COMPARE_OP_INT", uops)
-        self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
+        # TODO (gh-142764): Re-enable after we get back automatic constant propagation.
+        # self.assertNotIn("_COMPARE_OP_INT", uops)
+        # self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
 
     def test_call_len(self):
         def testfunc(n):
@@ -2131,8 +2133,9 @@ class C:
         # length allows us to optimize more code, such as conditionals
         # in this case
         self.assertIn("_CALL_LEN", uops)
-        self.assertNotIn("_COMPARE_OP_INT", uops)
-        self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
+        # TODO (gh-142764): Re-enable after we get back automatic constant propagation.
+        # self.assertNotIn("_COMPARE_OP_INT", uops)
+        # self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
 
     def test_call_builtin_o(self):
         def testfunc(n):
@@ -2207,8 +2210,9 @@ def testfunc(n):
         self.assertIsNotNone(ex)
         uops = get_opnames(ex)
         self.assertIn("_BINARY_OP_SUBSCR_TUPLE_INT", uops)
-        self.assertNotIn("_COMPARE_OP_INT", uops)
-        self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
+        # TODO (gh-142764): Re-enable after we get back automatic constant propagation.
+        # self.assertNotIn("_COMPARE_OP_INT", uops)
+        # self.assertNotIn("_GUARD_IS_TRUE_POP", uops)
 
     def test_call_isinstance_guards_removed(self):
         def testfunc(n):
@@ -2514,6 +2518,21 @@ def testfunc(n):
         self.assertIn("_POP_TOP_NOP", uops)
         self.assertNotIn("_POP_TOP", uops)
 
+    def test_int_cmp_op_refcount_elimination(self):
+        def testfunc(n):
+            c = 1
+            res = 0
+            for _ in range(n):
+                res = c == c
+            return res
+
+        res, ex = self._run_with_optimizer(testfunc, TIER2_THRESHOLD)
+        self.assertIsNotNone(ex)
+        uops = get_opnames(ex)
+        self.assertIn("_COMPARE_OP_INT", uops)
+        self.assertIn("_POP_TOP_NOP", uops)
+        self.assertNotIn("_POP_TOP", uops)
+
     def test_remove_guard_for_slice_list(self):
         def f(n):
             for i in range(n):

Include/internal/pycore_uop_ids.h

@@ -2701,7 +2701,7 @@ dummy_func(
             _GUARD_TOS_FLOAT + _GUARD_NOS_FLOAT + unused/1 + _COMPARE_OP_FLOAT;
 
         macro(COMPARE_OP_INT) =
-            _GUARD_TOS_INT + _GUARD_NOS_INT + unused/1 + _COMPARE_OP_INT;
+            _GUARD_TOS_INT + _GUARD_NOS_INT + unused/1 + _COMPARE_OP_INT + _POP_TOP_INT + _POP_TOP_INT;
 
         macro(COMPARE_OP_STR) =
             _GUARD_TOS_UNICODE + _GUARD_NOS_UNICODE + unused/1 + _COMPARE_OP_STR;
@@ -2724,7 +2724,7 @@ dummy_func(
         }
 
         // Similar to COMPARE_OP_FLOAT
-        op(_COMPARE_OP_INT, (left, right -- res)) {
+        op(_COMPARE_OP_INT, (left, right -- res, l, r)) {
             PyObject *left_o = PyStackRef_AsPyObjectBorrow(left);
             PyObject *right_o = PyStackRef_AsPyObjectBorrow(right);
 
@@ -2737,9 +2737,9 @@ dummy_func(
             Py_ssize_t iright = _PyLong_CompactValue((PyLongObject *)right_o);
             // 2 if <, 4 if >, 8 if ==; this matches the low 4 bits of the oparg
             int sign_ish = COMPARISON_BIT(ileft, iright);
-            PyStackRef_CLOSE_SPECIALIZED(left, _PyLong_ExactDealloc);
+            l = left;
+            r = right;
             DEAD(left);
-            PyStackRef_CLOSE_SPECIALIZED(right, _PyLong_ExactDealloc);
             DEAD(right);
             res =  (sign_ish & oparg) ? PyStackRef_True : PyStackRef_False;
             // It's always a bool, so we don't care about oparg & 16.

Include/internal/pycore_uop_metadata.h

@@ -446,9 +446,10 @@ dummy_func(void) {
         }
     }
 
-    op(_COMPARE_OP_INT, (left, right -- res)) {
-        REPLACE_OPCODE_IF_EVALUATES_PURE(left, right);
+    op(_COMPARE_OP_INT, (left, right -- res, l, r)) {
         res = sym_new_type(ctx, &PyBool_Type);
+        l = left;
+        r = right;
     }
 
     op(_COMPARE_OP_FLOAT, (left, right -- res)) {