anchor.diff:      } else {
         up = arg2;
       }
  -    Expect.equals(info.newRange(low, up), -range);
  +    Expect.equals(info.newNormalizedRange(low, up), -range);
     }
   }
   
  
positive.code: Range createSingleLengthRange() => createSingleRange(lengthValue);
  
  Range createIntRange(int lower, int upper) {
    return info.newRange(info.newIntValue(lower), info.newIntValue(upper));
  }
  
  Range createLengthRange(int lower) {
    return info.newRange(info.newIntValue(lower), lengthValue);
  }
  
  Range createInstructionRange(int lower) {
    return info.newRange(info.newIntValue(lower), instructionValue);
  }
  
  Range instruction = createSingleInstructionRange();
  
negative.code:     upper = info.newIntValue(upper);
    }
  
    Expect.equals(info.newNormalizedRange(lower, upper), one - two);
  }
  
  checkNegateRange(Range range, [arg1, arg2]) {
  