Victor: "I plan to run a benchmark when all my patches to reduce the stack consumption will be ready."

msg285200 of issue #28870: "I also ran the reliable performance benchmark suite with LTO+PGO. There is no significant performance change on these benchmarks (...)"

less_stack.patch:

-#define _PY_FASTCALL_SMALL_STACK 5
+#define _PY_FASTCALL_SMALL_STACK 3

With the issue #28870, reducing _PY_FASTCALL_SMALL_STACK value is no more needed. Larger _PY_FASTCALL_SMALL_STACK means better performances, so I prefer to keep the value 5 (arguments).

The main change, inline call_function(), was merged, so I close the issue.