Canonicalize NaNs on store to Fast(Float|Double) arrays

src/hydrogen-instructions.h

 // Copyright 2012 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:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5364 matching lines @@
       // Native code could change the specialized array.
       SetGVNFlag(kDependsOnCalls);
     }
 
     SetFlag(kUseGVN);
   }
 
   bool is_external() const {
     return IsExternalArrayElementsKind(elements_kind());
   }
+
+  bool can_load_hole_nan() const {
+    return elements_kind() == EXTERNAL_FLOAT_ELEMENTS
+      || elements_kind() == EXTERNAL_DOUBLE_ELEMENTS;

[Jakob Kummerow, 2013/03/28 10:17:38]

nit: 4 spaces indentation

+  }
+
   HValue* elements() { return OperandAt(0); }
   HValue* key() { return OperandAt(1); }
   HValue* dependency() {
     ASSERT(HasDependency());
     return OperandAt(2);
   }
   bool HasDependency() const { return OperandAt(0) != OperandAt(2); }
   uint32_t index_offset() { return IndexOffsetField::decode(bit_field_); }
   void SetIndexOffset(uint32_t index_offset) {
     bit_field_ = IndexOffsetField::update(bit_field_, index_offset);
@@ skipping 1065 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_