Operation* op, PatternRewriter& rewriter) const {
  rewriter.eraseOp(op);
  return success();
}

// Legalize unidirectional sequence lstm.
struct LegalizeUnidirectionalSequenceLstm : public RewritePattern {
  explicit LegalizeUnidirectionalSequenceLstm(MLIRContext* context)
      : RewritePattern(kUnidirectionalSequenceLstm, 1, context) {}

  LogicalResult matchAndRewrite(Operation* op,