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diff --git a/src/mongo/db/query/optimizer/cascades/physical_rewriter.h b/src/mongo/db/query/optimizer/cascades/physical_rewriter.h
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+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/db/query/optimizer/cascades/logical_rewriter.h"
+#include "mongo/db/query/optimizer/cascades/memo.h"
+#include "mongo/db/query/optimizer/utils/utils.h"
+
+namespace mongo::optimizer::cascades {
+
+class PhysicalRewriter {
+    friend class PropEnforcerVisitor;
+    friend class ImplementationVisitor;
+
+public:
+    struct OptimizeGroupResult {
+        OptimizeGroupResult();
+        OptimizeGroupResult(size_t index, CostType cost);
+
+        OptimizeGroupResult(const OptimizeGroupResult& other) = default;
+        OptimizeGroupResult(OptimizeGroupResult&& other) = default;
+
+        bool _success;
+        size_t _index;
+        CostType _cost;
+    };
+
+    PhysicalRewriter(Memo& memo,
+                     const QueryHints& hints,
+                     const opt::unordered_map<std::string, ProjectionName>& ridProjections,
+                     const CostingInterface& costDerivation,
+                     std::unique_ptr<LogicalRewriter>& logicalRewriter);
+
+    /**
+     * Main entry point for physical optimization.
+     * Optimize a logical plan rooted at a RootNode, and return an index into the winner's circle if
+     * successful.
+     */
+    OptimizeGroupResult optimizeGroup(GroupIdType groupId,
+                                      properties::PhysProps physProps,
+                                      PrefixId prefixId,
+                                      CostType costLimit);
+
+private:
+    void costAndRetainBestNode(ABT node,
+                               ChildPropsType childProps,
+                               NodeCEMap nodeCEMap,
+                               GroupIdType groupId,
+                               const PrefixId& prefixId,
+                               PhysOptimizationResult& bestResult);
+
+    std::pair<bool, CostType> optimizeChildren(CostType nodeCost,
+                                               ChildPropsType childProps,
+                                               const PrefixId& prefixId,
+                                               CostType costLimit);
+
+    // We don't own any of this.
+    Memo& _memo;
+    const CostingInterface& _costDerivation;
+    const QueryHints& _hints;
+    const opt::unordered_map<std::string, ProjectionName>& _ridProjections;
+    // If set, we'll perform logical rewrites as part of OptimizeGroup().
+    std::unique_ptr<LogicalRewriter>& _logicalRewriter;
+};
+
+}  // namespace mongo::optimizer::cascades