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diff --git a/icing/index/embed/embedding-hit.h b/icing/index/embed/embedding-hit.h
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+++ b/icing/index/embed/embedding-hit.h
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+// Copyright (C) 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ICING_INDEX_EMBED_EMBEDDING_HIT_H_
+#define ICING_INDEX_EMBED_EMBEDDING_HIT_H_
+
+#include <cstdint>
+
+#include "icing/index/hit/hit.h"
+
+namespace icing {
+namespace lib {
+
+class EmbeddingHit {
+ public:
+  // Order: basic_hit, location
+  // Value bits layout: 32 basic_hit + 32 location
+  using Value = uint64_t;
+
+  // WARNING: Changing this value will invalidate any pre-existing posting lists
+  // on user devices.
+  //
+  // kInvalidValue contains:
+  // - BasicHit of value 0, which is invalid.
+  // - location of 0 (valid), which is ok because BasicHit is already invalid.
+  static_assert(BasicHit::kInvalidValue == 0);
+  static constexpr Value kInvalidValue = 0;
+
+  explicit EmbeddingHit(BasicHit basic_hit, uint32_t location) {
+    value_ = (static_cast<uint64_t>(basic_hit.value()) << 32) | location;
+  }
+
+  explicit EmbeddingHit(Value value) : value_(value) {}
+
+  // BasicHit contains the document id and the section id.
+  BasicHit basic_hit() const { return BasicHit(value_ >> 32); }
+  // The location of the referred embedding vector in the vector storage.
+  uint32_t location() const { return value_ & 0xFFFFFFFF; };
+
+  bool is_valid() const { return basic_hit().is_valid(); }
+  Value value() const { return value_; }
+
+  bool operator<(const EmbeddingHit& h2) const { return value_ < h2.value_; }
+  bool operator==(const EmbeddingHit& h2) const { return value_ == h2.value_; }
+
+ private:
+  Value value_;
+};
+
+static_assert(sizeof(BasicHit) == 4);
+static_assert(sizeof(EmbeddingHit) == 8);
+
+}  // namespace lib
+}  // namespace icing
+
+#endif  // ICING_INDEX_EMBED_EMBEDDING_HIT_H_