Implement local load/store elimination on basic blocks.

src/hydrogen-load-elimination.h

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-#ifndef V8_HYDROGEN_CANONICALIZE_H_
-#define V8_HYDROGEN_CANONICALIZE_H_
+#ifndef V8_HYDROGEN_LOAD_ELIMINATION_H_
+#define V8_HYDROGEN_LOAD_ELIMINATION_H_
 
 #include "hydrogen.h"
 
 namespace v8 {
 namespace internal {
 
-
-class HCanonicalizePhase : public HPhase {
+class HLoadEliminationPhase : public HPhase {
  public:
-  explicit HCanonicalizePhase(HGraph* graph)
-      : HPhase("H_Canonicalize", graph) { }
+  explicit HLoadEliminationPhase(HGraph* graph)
+      : HPhase("H_Load elimination", graph) { }
 
   void Run();
 
  private:
-  DISALLOW_COPY_AND_ASSIGN(HCanonicalizePhase);
+  void EliminateLoads(HBasicBlock* block);
 };
 
 
 } }  // namespace v8::internal
 
-#endif  // V8_HYDROGEN_CANONICALIZE_H_
+#endif  // V8_HYDROGEN_LOAD_ELIMINATION_H_