[turbofan] Performance enhancements for escape analysis

src/compiler/escape-analysis.h

 // Copyright 2015 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_ESCAPE_ANALYSIS_H_
 #define V8_COMPILER_ESCAPE_ANALYSIS_H_
 
 #include "src/base/flags.h"
 #include "src/compiler/graph.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Forward declarations.
 class CommonOperatorBuilder;
 class EscapeAnalysis;
 class VirtualState;
 class VirtualObject;
 
 
 // EscapeStatusAnalysis determines for each allocation whether it escapes.
 class EscapeStatusAnalysis {
  public:
   ~EscapeStatusAnalysis();
 
   enum EscapeStatusFlag {
     kUnknown = 0u,
-    kVirtual = 1u << 0,
+    kTracked = 1u << 0,
     kEscaped = 1u << 1,
+    kOnStack = 1u << 2,
+    kVisited = 1u << 3,
   };
-  typedef base::Flags<EscapeStatusFlag> EscapeStatusFlags;
+  typedef base::Flags<EscapeStatusFlag, unsigned char> EscapeStatusFlags;
 
   void Run();
 
   bool IsVirtual(Node* node);
   bool IsEscaped(Node* node);
   bool IsAllocation(Node* node);
 
   void DebugPrint();
 
   friend class EscapeAnalysis;
@@ skipping 17 matching lines @@
   void Resize();
   size_t size();
   bool IsAllocationPhi(Node* node);
 
   Graph* graph() const { return graph_; }
   Zone* zone() const { return zone_; }
 
   EscapeAnalysis* object_analysis_;
   Graph* const graph_;
   Zone* const zone_;
-  ZoneVector<EscapeStatusFlags> info_;
+  ZoneVector<EscapeStatusFlags> status_;
   ZoneDeque<Node*> queue_;
 
   DISALLOW_COPY_AND_ASSIGN(EscapeStatusAnalysis);
 };
 
 
 DEFINE_OPERATORS_FOR_FLAGS(EscapeStatusAnalysis::EscapeStatusFlags)
 
 
 // Forward Declaration.
 class MergeCache;
 
 
 // EscapeObjectAnalysis simulates stores to determine values of loads if
 // an object is virtual and eliminated.
 class EscapeAnalysis {
  public:
+  typedef NodeId Alias;
+
   EscapeAnalysis(Graph* graph, CommonOperatorBuilder* common, Zone* zone);
   ~EscapeAnalysis();
 
   void Run();
 
   Node* GetReplacement(Node* node);
   bool IsVirtual(Node* node);
   bool IsEscaped(Node* node);
   bool CompareVirtualObjects(Node* left, Node* right);
   Node* GetOrCreateObjectState(Node* effect, Node* node);
 
  private:
   void RunObjectAnalysis();
+  void AssignAliases();
   bool Process(Node* node);
   void ProcessLoadField(Node* node);
   void ProcessStoreField(Node* node);
   void ProcessLoadElement(Node* node);
   void ProcessStoreElement(Node* node);
   void ProcessAllocationUsers(Node* node);
   void ProcessAllocation(Node* node);
   void ProcessFinishRegion(Node* node);
   void ProcessCall(Node* node);
   void ProcessStart(Node* node);
@@ skipping 11 matching lines @@
   Node* GetReplacementIfSame(ZoneVector<VirtualObject*>& objs);
 
   bool SetEscaped(Node* node);
   Node* replacement(NodeId id);
   Node* replacement(Node* node);
   Node* ResolveReplacement(Node* node);
   Node* GetReplacement(NodeId id);
   bool SetReplacement(Node* node, Node* rep);
   bool UpdateReplacement(VirtualState* state, Node* node, Node* rep);
 
+  VirtualObject* GetVirtualObject(VirtualState* state, Node* node);
+
   void DebugPrint();
   void DebugPrintState(VirtualState* state);
-  void DebugPrintObject(VirtualObject* state, NodeId id);
+  void DebugPrintObject(VirtualObject* state, Alias id);
+
+  Alias NextAlias() { return next_free_alias_++; }
+  Alias AliasCount() const { return next_free_alias_; }
 
   Graph* graph() const { return graph_; }
   CommonOperatorBuilder* common() const { return common_; }
   Zone* zone() const { return zone_; }
 
+  static const Alias kNotReachable;
+  static const Alias kUntrackable;
   Graph* const graph_;
   CommonOperatorBuilder* const common_;
   Zone* const zone_;
   ZoneVector<VirtualState*> virtual_states_;
   ZoneVector<Node*> replacements_;
   EscapeStatusAnalysis escape_status_;
   MergeCache* cache_;
+  ZoneVector<Alias> aliases_;
+  Alias next_free_alias_;
 
   DISALLOW_COPY_AND_ASSIGN(EscapeAnalysis);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_ESCAPE_ANALYSIS_H_