SERVER-48228 Move slot-based execution engine and supporting changes into the master branch

This is an initial commit for the slot-based execution engine (SBE) which contains:
   * Implementation of the core slot-based engine.
   * The SBE stage builder, which is responsible for translating a QuerySolution tree
     into an SBE plan.
   * Other changes necessary for integration with the find command.

Co-authored-by: Anton Korshunov <anton.korshunov@mongodb.com>
Co-authored-by: Justin Seyster <justin.seyster@mongodb.com>
Co-authored-by: David Storch <david.storch@mongodb.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/src/mongo/db/query/stage_builder_util.cpp b/src/mongo/db/query/stage_builder_util.cpp
new file mode 100644
index 00000000000..5f7c6c462e3
--- /dev/null
+++ b/src/mongo/db/query/stage_builder_util.cpp
@@ -0,0 +1,78 @@
+/**
+ *    Copyright (C) 2020-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.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/query/stage_builder_util.h"
+
+#include "mongo/db/query/classic_stage_builder.h"
+#include "mongo/db/query/plan_yield_policy.h"
+#include "mongo/db/query/sbe_stage_builder.h"
+
+namespace mongo::stage_builder {
+std::unique_ptr<PlanStage> buildClassicExecutableTree(OperationContext* opCtx,
+                                                      const Collection* collection,
+                                                      const CanonicalQuery& cq,
+                                                      const QuerySolution& solution,
+                                                      WorkingSet* ws) {
+    // Only QuerySolutions derived from queries parsed with context, or QuerySolutions derived from
+    // queries that disallow extensions, can be properly executed. If the query does not have
+    // $text/$where context (and $text/$where are allowed), then no attempt should be made to
+    // execute the query.
+    invariant(!cq.canHaveNoopMatchNodes());
+    invariant(solution.root);
+    invariant(ws);
+    auto builder = std::make_unique<ClassicStageBuilder>(opCtx, collection, cq, solution, ws);
+    return builder->build(solution.root.get());
+}
+
+std::pair<std::unique_ptr<sbe::PlanStage>, stage_builder::PlanStageData>
+buildSlotBasedExecutableTree(OperationContext* opCtx,
+                             const Collection* collection,
+                             const CanonicalQuery& cq,
+                             const QuerySolution& solution,
+                             PlanYieldPolicy* yieldPolicy,
+                             bool needsTrialRunProgressTracker) {
+    // Only QuerySolutions derived from queries parsed with context, or QuerySolutions derived from
+    // queries that disallow extensions, can be properly executed. If the query does not have
+    // $text/$where context (and $text/$where are allowed), then no attempt should be made to
+    // execute the query.
+    invariant(!cq.canHaveNoopMatchNodes());
+    invariant(solution.root);
+
+    auto sbeYieldPolicy = dynamic_cast<PlanYieldPolicySBE*>(yieldPolicy);
+    invariant(sbeYieldPolicy);
+
+    auto builder = std::make_unique<SlotBasedStageBuilder>(
+        opCtx, collection, cq, solution, sbeYieldPolicy, needsTrialRunProgressTracker);
+    auto root = builder->build(solution.root.get());
+    auto data = builder->getPlanStageData();
+    return {std::move(root), std::move(data)};
+}
+}  // namespace mongo::stage_builder