anchor.diff:      show FieldAnalysisData, JFieldAnalysis;
   import '../js_backend/backend.dart' show CodegenInputs;
   import '../js_backend/native_data.dart' show NativeData;
  -import '../js_backend/runtime_types_codegen.dart';
   import '../js_model/type_recipe.dart'
       show
           TypeRecipe,
  
positive.code:             closedWorld.commonElements, closedWorld, log),
          // After type propagation, more instructions can be
          // simplified.
          new SsaInstructionSimplifier(
              globalInferenceResults,
              _options,
              codegen.rtiSubstitutions,
              closedWorld,
              typeRecipeDomain,
              registry,
              log),
          new SsaInstructionSimplifier(
              globalInferenceResults,
              _options,
              codegen.rtiSubstitutions,
              closedWorld,
              typeRecipeDomain,
              registry,
              log),
          new SsaTypePropagator(globalInferenceResults,
              closedWorld.commonElements, closedWorld, log),
          // Run a dead code eliminator before LICM because dead
  
negative.code:           new SsaGlobalValueNumberer(closedWorld.abstractValueDomain),
            new SsaCodeMotion(closedWorld.abstractValueDomain),
            new SsaValueRangeAnalyzer(closedWorld, this),
            new SsaInstructionSimplifier(globalInferenceResults, _options,
                closedWorld, typeRecipeDomain, registry, log),
            new SsaSimplifyInterceptors(closedWorld, member.enclosingClass),
            new SsaDeadCodeEliminator(closedWorld, this),
          ];
  