docs: public @CheckForNull
      IsNullValue getDecision(int edgeType) {
          switch (edgeType) {
          case EdgeTypes.IFCMP_EDGE:
              return ifcmpDecision;
          case EdgeTypes.FALL_THROUGH_EDGE:
              return fallThroughDecision;
          default:
              throw new IllegalArgumentException("Bad edge type: " + edgeType);
          }
      }