Initial commit

packages/leann-backend-diskann/third_party/DiskANN/include/abstract_scratch.h

@@ -0,0 +1,35 @@
+#pragma once
+namespace diskann
+{
+
+template <typename data_t> class PQScratch;
+
+// By somewhat more than a coincidence, it seems that both InMemQueryScratch
+// and SSDQueryScratch have the aligned query and PQScratch objects. So we
+// can put them in a neat hierarchy and keep PQScratch as a standalone class.
+template <typename data_t> class AbstractScratch
+{
+  public:
+    AbstractScratch() = default;
+    // This class does not take any responsibilty for memory management of
+    // its members. It is the responsibility of the derived classes to do so.
+    virtual ~AbstractScratch() = default;
+
+    // Scratch objects should not be copied
+    AbstractScratch(const AbstractScratch &) = delete;
+    AbstractScratch &operator=(const AbstractScratch &) = delete;
+
+    data_t *aligned_query_T()
+    {
+        return _aligned_query_T;
+    }
+    PQScratch<data_t> *pq_scratch()
+    {
+        return _pq_scratch;
+    }
+
+  protected:
+    data_t *_aligned_query_T = nullptr;
+    PQScratch<data_t> *_pq_scratch = nullptr;
+};
+} // namespace diskann