Tier 2 cleanups and tweaks (#115534)

* Rename `_testinternalcapi.get_{uop,counter}_optimizer` to `new_*_optimizer`
* Use `_PyUOpName()` instead of` _PyOpcode_uop_name[]`
* Add `target` to executor iterator items -- `list(ex)` now returns `(opcode, oparg, target, operand)` quadruples
* Add executor methods `get_opcode()` and `get_oparg()` to get `vmdata.opcode`, `vmdata.oparg`
* Define a helper for printing uops, and unify various places where they are printed
* Add a hack to summarize_stats.py to fix legacy uop names (e.g. `POP_TOP` -> `_POP_TOP`)
* Define helpers in `test_opt.py` for accessing the set or list of opnames of an executor

Tools/scripts/summarize_stats.py

@@ -102,6 +102,10 @@ def load_raw_data(input: Path) -> RawData:
                             file=sys.stderr,
                         )
                         continue
+                    # Hack to handle older data files where some uops
+                    # are missing an underscore prefix in their name
+                    if key.startswith("uops[") and key[5:6] != "_":
+                        key = "uops[_" + key[5:]
                     stats[key.strip()] += int(value)
             stats["__nfiles__"] += 1