anchor.diff:        } else {
           block.rewriteWithBetterUser(current, existing);
           block.remove(current);
  +        movedCode = true;
         }
       }
     }
  
positive.code: class SsaCodeMotion extends HBaseVisitor implements OptimizationPhase {
    final String name = "SsaCodeMotion";
  
    List<ValueSet> values;
  
    void visitGraph(HGraph graph) {
  
negative.code:     ConstantSystem constantSystem = compiler.backend.constantSystem;
      bool trustPrimitives = compiler.options.trustPrimitives;
      Set<HInstruction> boundsChecked = new Set<HInstruction>();
      SsaCodeMotion codeMotion;
      measure(() {
        List<OptimizationPhase> phases = <OptimizationPhase>[
          // Run trivial instruction simplification first to optimize
  