GH-126222: Fix _PyUop_num_popped

Lib/test/test_capi/test_opt.py

@@ -1486,6 +1486,14 @@ def fn(a):
 
         fn(A())
 
+    def test_jit_error_pops(self):
+        """
+        Tests that the correct number of pops are inserted into the
+        exit stub
+        """
+        items = 17 * [None] + [[]]
+        with self.assertRaises(TypeError):
+            {item for item in items}
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Core_and_Builtins/2024-11-06-16-34-11.gh-issue-126222.9NBfTn.rst

@@ -0,0 +1,3 @@
+Do not include count of "peek" items in ``_PyUop_num_popped``. This ensures
+that the correct number of items are popped from the stack when a micro-op
+exits with an error.

Tools/cases_generator/uop_metadata_generator.py

@@ -51,6 +51,8 @@ def generate_names_and_flags(analysis: Analysis, out: CWriter) -> None:
         if uop.is_viable() and uop.properties.tier != 1:
             stack = Stack()
             for var in reversed(uop.stack.inputs):
+                if var.peek:
+                    break
                 stack.pop(var)
             popped = (-stack.base_offset).to_c()
             out.emit(f"case {uop.name}:\n")