// outlives this object.
  explicit AddCustomAggregationOp(MLIRContext *context,
                                  const CalibrationOptions &calib_opts)
      : RewritePattern(MatchAnyOpTypeTag(), /*benefit=*/1, context),
        calib_opts_(calib_opts) {}

  LogicalResult matchAndRewrite(Operation *op,
                                PatternRewriter &rewriter) const override {

// identifying `erf` ops and validate the structure around them.
class OutlineGELU : public RewritePattern {
 public:
  explicit OutlineGELU(MLIRContext* context)
      : RewritePattern(MatchAnyOpTypeTag(), /*benefit=*/1, context) {}

  LogicalResult matchAndRewrite(Operation* op,
                                PatternRewriter& rewriter) const override {
    if (!MatchERF(op)) return failure();
    // `add 1`

  }
};

class ConvertGeneralOp : public ConversionPattern {
 public:
  ConvertGeneralOp(MLIRContext *context,
                   const DenseSet<StringRef> &func_symbols)
      : ConversionPattern(MatchAnyOpTypeTag(), PatternBenefit(1), context),
        func_symbols_(func_symbols) {}

  LogicalResult matchAndRewrite(
      Operation *op, llvm::ArrayRef<Value> operands,
      ConversionPatternRewriter &rewriter) const final {

// the debug model creation.
class RemoveDebugAttrPattern : public RewritePattern {
 public:
  explicit RemoveDebugAttrPattern(MLIRContext* context)
      : RewritePattern(MatchAnyOpTypeTag(), /*benefit=*/1, context) {}
  LogicalResult matchAndRewrite(Operation* op,
                                PatternRewriter& rewriter) const override;
};