Reverting r4703.

src/x64/macro-assembler-x64.h

 // Copyright 2009 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 60 matching lines @@
 
   void LoadRoot(Register destination, Heap::RootListIndex index);
   void CompareRoot(Register with, Heap::RootListIndex index);
   void CompareRoot(Operand with, Heap::RootListIndex index);
   void PushRoot(Heap::RootListIndex index);
   void StoreRoot(Register source, Heap::RootListIndex index);
 
   // ---------------------------------------------------------------------------
   // GC Support
 
-  // For page containing |object| mark region covering |addr| dirty.
-  // RecordWriteHelper only works if the object is not in new
+  // Set the remebered set bit for an address which points into an
+  // object. RecordWriteHelper only works if the object is not in new
   // space.
   void RecordWriteHelper(Register object,
                          Register addr,
                          Register scratch);
 
   // Check if object is in new space. The condition cc can be equal or
   // not_equal. If it is equal a jump will be done if the object is on new
   // space. The register scratch can be object itself, but it will be clobbered.
   void InNewSpace(Register object,
                   Register scratch,
                   Condition cc,
                   Label* branch);
 
-  // For page containing |object| mark region covering [object+offset] dirty.
+  // Set the remembered set bit for [object+offset].
   // object is the object being stored into, value is the object being stored.
   // If offset is zero, then the scratch register contains the array index into
   // the elements array represented as a Smi.
   // All registers are clobbered by the operation.
   void RecordWrite(Register object,
                    int offset,
                    Register value,
                    Register scratch);
 
-  // For page containing |object| mark region covering [object+offset] dirty.
+  // Set the remembered set bit for [object+offset].
   // The value is known to not be a smi.
   // object is the object being stored into, value is the object being stored.
   // If offset is zero, then the scratch register contains the array index into
   // the elements array represented as a Smi.
   // All registers are clobbered by the operation.
   void RecordWriteNonSmi(Register object,
                          int offset,
                          Register value,
                          Register scratch);
 
@@ skipping 96 matching lines @@
 
   // Convert smi to 64-bit integer (sign extended if necessary).
   void SmiToInteger64(Register dst, Register src);
 
   // Multiply a positive smi's integer value by a power of two.
   // Provides result as 64-bit integer value.
   void PositiveSmiTimesPowerOfTwoToInteger64(Register dst,
                                              Register src,
                                              int power);
 
-  // Divide a positive smi's integer value by a power of two.
-  // Provides result as 32-bit integer value.
-  void PositiveSmiDivPowerOfTwoToInteger32(Register dst,
-                                           Register src,
-                                           int power);
-
-
   // Simple comparison of smis.
   void SmiCompare(Register dst, Register src);
   void SmiCompare(Register dst, Smi* src);
   void SmiCompare(Register dst, const Operand& src);
   void SmiCompare(const Operand& dst, Register src);
   void SmiCompare(const Operand& dst, Smi* src);
   // Sets sign and zero flags depending on value of smi in register.
   void SmiTest(Register src);
 
   // Functions performing a check on a known or potential smi. Returns
@@ skipping 643 matching lines @@
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_