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diff --git a/deps/v8/src/compiler/csa-load-elimination.h b/deps/v8/src/compiler/csa-load-elimination.h
new file mode 100644
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+++ b/deps/v8/src/compiler/csa-load-elimination.h
@@ -0,0 +1,118 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_COMPILER_CSA_LOAD_ELIMINATION_H_
+#define V8_COMPILER_CSA_LOAD_ELIMINATION_H_
+
+#include "src/base/compiler-specific.h"
+#include "src/codegen/machine-type.h"
+#include "src/common/globals.h"
+#include "src/compiler/graph-reducer.h"
+#include "src/compiler/js-graph.h"
+#include "src/compiler/node-aux-data.h"
+#include "src/compiler/persistent-map.h"
+#include "src/handles/maybe-handles.h"
+#include "src/zone/zone-handle-set.h"
+
+namespace v8 {
+namespace internal {
+
+namespace compiler {
+
+// Forward declarations.
+class CommonOperatorBuilder;
+struct ObjectAccess;
+class Graph;
+class JSGraph;
+
+class V8_EXPORT_PRIVATE CsaLoadElimination final
+    : public NON_EXPORTED_BASE(AdvancedReducer) {
+ public:
+  CsaLoadElimination(Editor* editor, JSGraph* jsgraph, Zone* zone)
+      : AdvancedReducer(editor),
+        empty_state_(zone),
+        node_states_(jsgraph->graph()->NodeCount(), zone),
+        jsgraph_(jsgraph),
+        zone_(zone) {}
+  ~CsaLoadElimination() final = default;
+
+  const char* reducer_name() const override { return "CsaLoadElimination"; }
+
+  Reduction Reduce(Node* node) final;
+
+ private:
+  struct FieldInfo {
+    FieldInfo() = default;
+    FieldInfo(Node* value, MachineRepresentation representation)
+        : value(value), representation(representation) {}
+
+    bool operator==(const FieldInfo& other) const {
+      return value == other.value && representation == other.representation;
+    }
+
+    bool operator!=(const FieldInfo& other) const { return !(*this == other); }
+
+    bool IsEmpty() const { return value == nullptr; }
+
+    Node* value = nullptr;
+    MachineRepresentation representation = MachineRepresentation::kNone;
+  };
+
+  class AbstractState final : public ZoneObject {
+   public:
+    explicit AbstractState(Zone* zone) : field_infos_(zone) {}
+
+    bool Equals(AbstractState const* that) const {
+      return field_infos_ == that->field_infos_;
+    }
+    void Merge(AbstractState const* that, Zone* zone);
+
+    AbstractState const* KillField(Node* object, Node* offset,
+                                   MachineRepresentation repr,
+                                   Zone* zone) const;
+    AbstractState const* AddField(Node* object, Node* offset, FieldInfo info,
+                                  Zone* zone) const;
+    FieldInfo Lookup(Node* object, Node* offset) const;
+
+    void Print() const;
+
+   private:
+    using Field = std::pair<Node*, Node*>;
+    using FieldInfos = PersistentMap<Field, FieldInfo>;
+    FieldInfos field_infos_;
+  };
+
+  Reduction ReduceLoadFromObject(Node* node, ObjectAccess const& access);
+  Reduction ReduceStoreToObject(Node* node, ObjectAccess const& access);
+  Reduction ReduceEffectPhi(Node* node);
+  Reduction ReduceStart(Node* node);
+  Reduction ReduceCall(Node* node);
+  Reduction ReduceOtherNode(Node* node);
+
+  Reduction UpdateState(Node* node, AbstractState const* state);
+  Reduction PropagateInputState(Node* node);
+
+  AbstractState const* ComputeLoopState(Node* node,
+                                        AbstractState const* state) const;
+
+  CommonOperatorBuilder* common() const;
+  Isolate* isolate() const;
+  Graph* graph() const;
+  JSGraph* jsgraph() const { return jsgraph_; }
+  Zone* zone() const { return zone_; }
+  AbstractState const* empty_state() const { return &empty_state_; }
+
+  AbstractState const empty_state_;
+  NodeAuxData<AbstractState const*> node_states_;
+  JSGraph* const jsgraph_;
+  Zone* zone_;
+
+  DISALLOW_COPY_AND_ASSIGN(CsaLoadElimination);
+};
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_COMPILER_CSA_LOAD_ELIMINATION_H_