gh-131798: JIT: Propagate the result in `_BINARY_OP_SUBSCR_TUPLE_INT` (GH-133003)

1 files changed, 21 insertions, 0 deletions

diff --git a/Python/optimizer_bytecodes.c b/Python/optimizer_bytecodes.c
index 040e544..f862c9c 100644
--- a/Python/optimizer_bytecodes.c
+++ b/Python/optimizer_bytecodes.c
@@ -370,6 +370,27 @@ dummy_func(void) {
         res = sym_new_type(ctx, &PyUnicode_Type);
     }
 
+    op(_BINARY_OP_SUBSCR_TUPLE_INT, (tuple_st, sub_st -- res)) {
+        assert(sym_matches_type(tuple_st, &PyTuple_Type));
+        if (sym_is_const(ctx, sub_st)) {
+            assert(PyLong_CheckExact(sym_get_const(ctx, sub_st)));
+            long index = PyLong_AsLong(sym_get_const(ctx, sub_st));
+            assert(index >= 0);
+            int tuple_length = sym_tuple_length(tuple_st);
+            if (tuple_length == -1) {
+                // Unknown length
+                res = sym_new_not_null(ctx);
+            }
+            else {
+                assert(index < tuple_length);
+                res = sym_tuple_getitem(ctx, tuple_st, index);
+            }
+        }
+        else {
+            res = sym_new_not_null(ctx);
+        }
+    }
+
     op(_TO_BOOL, (value -- res)) {
         int already_bool = optimize_to_bool(this_instr, ctx, value, &res);
         if (!already_bool) {