private void processBlock(PsiSwitchBlock block) {
        List<PsiExpression> branches = extractBranches(block);
        if (branches == null) return;
        PsiExpression[] diffs = findDiffs(block, branches);
        if (diffs.length != 0) {
          holder.registerProblem(block.getFirstChild(),
                                 InspectionGadgetsBundle.message("inspection.common.subexpression.in.switch.display.name"),
                                 new PushDownSwitchExpressionFix());
        }
      }
private void processBlock(PsiSwitchBlock block)