First simplistic implementation of escape analysis.

src/hydrogen-escape-analysis.h

Index: src/hydrogen-escape-analysis.h
diff --git a/src/vm-state.h b/src/hydrogen-escape-analysis.h
similarity index 75%
copy from src/vm-state.h
copy to src/hydrogen-escape-analysis.h
index 765b5701595b7f9637da05b0783662d603506463..1d31f3dce7e789320c7fdd8439a9f11e1bb35236 100644
--- a/src/vm-state.h
+++ b/src/hydrogen-escape-analysis.h
@@ -1,4 +1,4 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -25,37 +25,33 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifndef V8_VM_STATE_H_
-#define V8_VM_STATE_H_
+#ifndef V8_HYDROGEN_ESCAPE_ANALYSIS_H_
+#define V8_HYDROGEN_ESCAPE_ANALYSIS_H_
 
 #include "allocation.h"
-#include "isolate.h"
+#include "hydrogen.h"
 
 namespace v8 {
 namespace internal {
 
-template <StateTag Tag>
-class VMState BASE_EMBEDDED {
- public:
-  explicit inline VMState(Isolate* isolate);
-  inline ~VMState();
 
- private:
-  Isolate* isolate_;
-  StateTag previous_tag_;
-};
+class HEscapeAnalysis BASE_EMBEDDED {
+ public:
+  explicit HEscapeAnalysis(HGraph* graph)
+      : graph_(graph), zone_(graph->zone()), captured_(0, zone_) { }
 
+  void Analyze();
 
-class ExternalCallbackScope BASE_EMBEDDED {
- public:
-  inline ExternalCallbackScope(Isolate* isolate, Address callback);
-  inline ~ExternalCallbackScope();
  private:
-  Isolate* isolate_;
-  Address previous_callback_;
+  void CollectCapturedValues();
+  void CollectIfNoEscapingUses(HInstruction* instr);
+
+  HGraph* graph_;
+  Zone* zone_;
+  ZoneList<HValue*> captured_;
 };
 
-} }  // namespace v8::internal
 
+} }  // namespace v8::internal
 
-#endif  // V8_VM_STATE_H_
+#endif  // V8_HYDROGEN_ESCAPE_ANALYSIS_H_