anchor.diff:    // Supported modes.
     static const List<String> modes = [
       // Cluster options:
  -    'jit-opt-debug-ia32',
  -    'jit-opt-debug-x64',
  -    'jit-opt-debug-arm32',
  -    'jit-opt-debug-arm64',
  -    'jit-opt-debug-dbc',
  -    'jit-opt-debug-dbc64',
  -    'jit-opt-ia32',
  -    'jit-opt-x64',
  -    'jit-opt-arm32',
  -    'jit-opt-arm64',
  -    'jit-opt-dbc',
  -    'jit-opt-dbc64',
       'jit-debug-ia32',
       'jit-debug-x64',
       'jit-debug-arm32',
  
positive.code:     // Random when not set.
      if (mode == null || mode == '') {
        // Pick a mode at random (cluster), different from other.
        int cluster_modes = modes.length - 3;
        Random rand = new Random();
        do {
          mode = modes[rand.nextInt(cluster_modes)];
  
negative.code:     'aot-debug-arm64',
      'aot-arm64',
      // Too many divergences (due to arithmetic):
      'js',
      // https://github.com/dart-lang/sdk/issues/35196
      'jit-opt-debug-ia32',
      'jit-opt-debug-x64',
      'jit-opt-debug-arm32',
      'jit-opt-debug-arm64',
      'jit-opt-debug-dbc',
      'jit-opt-debug-dbc64',
      'jit-opt-ia32',
      'jit-opt-x64',
      'jit-opt-arm32',
      'jit-opt-arm64',
      'jit-opt-dbc',
      'jit-opt-dbc64',
    ];
  }
  
  