Implement code stub for object literal creation.

src/code-stubs.h

 // Copyright 2011 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 40 matching lines @@
   V(RegExpExec)                          \
   V(TranscendentalCache)                 \
   V(Instanceof)                          \
   V(ConvertToDouble)                     \
   V(WriteInt32ToHeapNumber)              \
   V(StackCheck)                          \
   V(FastNewClosure)                      \
   V(FastNewContext)                      \
   V(FastNewBlockContext)                 \
   V(FastCloneShallowArray)               \
+  V(FastCloneShallowObject)              \
   V(ToBoolean)                           \
   V(ToNumber)                            \
   V(ArgumentsAccess)                     \
   V(RegExpConstructResult)               \
   V(NumberToString)                      \
   V(CEntry)                              \
   V(JSEntry)                             \
   V(KeyedLoadElement)                    \
   V(KeyedStoreElement)                   \
   V(DebuggerStatement)                   \
@@ skipping 284 matching lines @@
   enum Mode {
     CLONE_ELEMENTS,
     CLONE_DOUBLE_ELEMENTS,
     COPY_ON_WRITE_ELEMENTS,
     CLONE_ANY_ELEMENTS
   };
 
   FastCloneShallowArrayStub(Mode mode, int length)
       : mode_(mode),
         length_((mode == COPY_ON_WRITE_ELEMENTS) ? 0 : length) {
-    ASSERT(length_ >= 0);
-    ASSERT(length_ <= kMaximumClonedLength);
+    ASSERT_GE(length_, 0);
+    ASSERT_LE(length_, kMaximumClonedLength);
   }
 
   void Generate(MacroAssembler* masm);
 
  private:
   Mode mode_;
   int length_;
 
   Major MajorKey() { return FastCloneShallowArray; }
   int MinorKey() {
     ASSERT(mode_ == 0 || mode_ == 1 || mode_ == 2 || mode_ == 3);
     return length_ * 4 +  mode_;
   }
 };
 
 
+class FastCloneShallowObjectStub : public CodeStub {
+ public:
+  // Maximum number of properties in copied object.
+  static const int kMaximumClonedProperties = 6;
+
+  FastCloneShallowObjectStub(int length) : length_(length) {
+    ASSERT_GE(length_, 0);
+    ASSERT_LE(length_, kMaximumClonedProperties);
+  }
+
+  void Generate(MacroAssembler* masm);
+
+ private:
+  int length_;
+
+  Major MajorKey() { return FastCloneShallowObject; }
+  int MinorKey() { return length_; }
+};
+
+
 class InstanceofStub: public CodeStub {
  public:
   enum Flags {
     kNoFlags = 0,
     kArgsInRegisters = 1 << 0,
     kCallSiteInlineCheck = 1 << 1,
     kReturnTrueFalseObject = 1 << 2
   };
 
   explicit InstanceofStub(Flags flags) : flags_(flags) { }
@@ skipping 670 matching lines @@
   int MinorKey() { return 0; }
 
   void Generate(MacroAssembler* masm);
 
   DISALLOW_COPY_AND_ASSIGN(StoreArrayLiteralElementStub);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_