[turbofan] escape analysis supports arguments object and rest elements

src/compiler/escape-analysis-reducer.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_REDUCER_H_
 #define V8_COMPILER_ESCAPE_ANALYSIS_REDUCER_H_
 
 #include "src/base/compiler-specific.h"
 #include "src/bit-vector.h"
 #include "src/compiler/escape-analysis.h"
 #include "src/compiler/graph-reducer.h"
 #include "src/globals.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Forward declarations.
 class JSGraph;
 
 class V8_EXPORT_PRIVATE EscapeAnalysisReducer final
     : public NON_EXPORTED_BASE(AdvancedReducer) {
  public:
   EscapeAnalysisReducer(Editor* editor, JSGraph* jsgraph,
                         EscapeAnalysis* escape_analysis, Zone* zone);
 
   Reduction Reduce(Node* node) final;
 
+  void Finalize() override;
+
   // Verifies that all virtual allocation nodes have been dealt with. Run it
   // after this reducer has been applied. Has no effect in release mode.
   void VerifyReplacement() const;
 
   bool compilation_failed() const { return compilation_failed_; }
 
  private:
   Reduction ReduceNode(Node* node);
   Reduction ReduceLoad(Node* node);
   Reduction ReduceStore(Node* node);
@@ skipping 12 matching lines @@
   EscapeAnalysis* escape_analysis() const { return escape_analysis_; }
   Zone* zone() const { return zone_; }
 
   JSGraph* const jsgraph_;
   EscapeAnalysis* escape_analysis_;
   Zone* const zone_;
   // This bit vector marks nodes we already processed (allocs, loads, stores)
   // and nodes that do not need a visit from ReduceDeoptState etc.
   BitVector fully_reduced_;
   bool exists_virtual_allocate_;
+  std::set<Node*> arguments_elements_;

[Tobias Tebbi, 2017/02/15 14:16:05]

This is a small set, at most 2 elements, and only constructed once per
compilation. Is this OK, or does it have to be zone memory?

   bool compilation_failed_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(EscapeAnalysisReducer);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_ESCAPE_ANALYSIS_REDUCER_H_