[analyzer] CmpRuns.py: Fix error due to statistics differences

[NoQ]

Aha, that probably broke when i added timers for visitors!

clang/utils/analyzer/CmpRuns.py

 
 
 # TODO: compare_results decouples comparison from the output, we should
 #       do it here as well
 def compare_stats(results_old: AnalysisRun, results_new: AnalysisRun):
     stats_old = derive_stats(results_old)
     stats_new = derive_stats(results_new)
 
-    keys = sorted(stats_old.keys())
+    old_keys = set(stats_old.keys())
+    new_keys = set(stats_new.keys())
+    keys = sorted(old_keys & new_keys)
 
-    # FIXME: stats_old and stats_new are not necessarily sharing all of their
-    #        stats and can crash when stats_new doesn't have/removed some
     for key in keys:
         print(key)
 
-        for kkey in stats_old[key]:
-            val_old = float(stats_old[key][kkey])
-            val_new = float(stats_new[key][kkey])
+        nested_keys = sorted(set(stats_old[key]) & set(stats_new[key]))
+
+        for nested_key in nested_keys:
+            val_old = float(stats_old[key][nested_key])
+            val_new = float(stats_new[key][nested_key])
 
             report = f"{val_old:.3f} -> {val_new:.3f}"
 
             # Only apply highlighting when writing to TTY and it's not Windows
             if sys.stdout.isatty() and os.name != 'nt':
                 if val_new != 0:
                     ratio = (val_new - val_old) / val_new
                     if ratio < -0.2:
                         report = Colors.GREEN + report + Colors.CLEAR
                     elif ratio > 0.2:
                         report = Colors.RED + report + Colors.CLEAR
 
-            print(f"\t {kkey} {report}")
+            print(f"\t {nested_key} {report}")
+
+    removed_keys = old_keys - new_keys
+    if removed_keys:
+        print(f"REMOVED statistics: {removed_keys}")
+
+    added_keys = new_keys - old_keys
+    if added_keys:
+        print(f"ADDED statistics: {added_keys}")
+
+    print()
 
 
 def dump_scan_build_results_diff(dir_old: str, dir_new: str,
                                  args: argparse.Namespace,
                                  delete_empty: bool = True,
                                  out: TextIO = sys.stdout):
     # Load the run results.
     results_old = load_results(dir_old, args, args.root_old, delete_empty)