Tighten specialization guards and add send_none fastpath by youknowone · Pull Request #7359 · RustPython/RustPython

- Implement specialization_eval_frame_active to check vm.use_tracing
  so specializations are skipped when tracing/profiling is active
- Add send_none fastpath in SendGen handler for the common None case

…7359)

* vm: align specialization guards with CPython patterns

* vm: tighten call specialization runtime guards

* vm: add send_none fastpath for generator specialization

* vm: restrict method-descriptor specialization to methods

* vm: deopt call specializations on guard misses

* vm: match CPython send/for-iter closed-frame guards

* vm: restrict len/isinstance specialization to builtins

* vm: use exact-type guards for call specializations

* vm: align class-call specialization flow with CPython

* vm: prefer FAST call opcodes for positional builtin calls

* vm: add callable identity guard to CALL_LIST_APPEND

* vm: make CALL_LIST_APPEND runtime guard pointer-based

* vm: align call guard cache and fallback behavior with CPython

* vm: use base vectorcall fallback for EXIT-style call misses

* vm: simplify CALL_LEN/CALL_ISINSTANCE runtime guards

* vm: infer call-convention flags for CPython-style CALL specialization

* vm: check use_tracing in eval_frame_active, add SendGen send_none

- Implement specialization_eval_frame_active to check vm.use_tracing
  so specializations are skipped when tracing/profiling is active
- Add send_none fastpath in SendGen handler for the common None case