GH-131798: Type-propagate string/list/tuple slices (GH-134671)

2025-06-07 14:08:44 -07:00
parent ac9c3431cc
commit 8fdbbf8b18
4 changed files with 55 additions and 3 deletions
--- a/Python/optimizer_cases.c.h
+++ b/Python/optimizer_cases.c.h
@@ -568,8 +568,19 @@
        }

        case _BINARY_SLICE: {
+            JitOptSymbol *container;
            JitOptSymbol *res;
-            res = sym_new_not_null(ctx);
+            container = stack_pointer[-3];
+            PyTypeObject *type = sym_get_type(container);
+            if (type == &PyUnicode_Type ||
+                type == &PyList_Type ||
+                type == &PyTuple_Type)
+            {
+                res = sym_new_type(ctx, type);
+            }
+            else {
+                res = sym_new_not_null(ctx);
+            }
            stack_pointer[-3] = res;
            stack_pointer += -2;
            assert(WITHIN_STACK_BOUNDS());