Make class BitField able to use 32 bits of a uint32....

src/codegen.h

 // Copyright 2006-2008 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 500 matching lines @@
 
 #ifdef DEBUG
   void Print() {
     PrintF("CallFunctionStub (args %d, in_loop %d, flags %d)\n",
            argc_,
            static_cast<int>(in_loop_),
            static_cast<int>(flags_));
   }
 #endif
 
-  // Minor key encoding in 31 bits AAAAAAAAAAAAAAAAAAAAAFI A(rgs)F(lag)I(nloop).
+  // Minor key encoding in 32 bits with Bitfield <Type, shift, size>.
   class InLoopBits: public BitField<InLoopFlag, 0, 1> {};
   class FlagBits: public BitField<CallFunctionFlags, 1, 1> {};
-  class ArgcBits: public BitField<int, 2, 29> {};
+  class ArgcBits: public BitField<int, 2, 32 - 2> {};
 
   Major MajorKey() { return CallFunction; }
   int MinorKey() {
-    // Encode the parameters in a unique 31 bit value.
+    // Encode the parameters in a unique 32 bit value.
     return InLoopBits::encode(in_loop_)
            | FlagBits::encode(flags_)
            | ArgcBits::encode(argc_);
   }
 
   InLoopFlag InLoop() { return in_loop_; }
   bool ReceiverMightBeValue() {
     return (flags_ & RECEIVER_MIGHT_BE_VALUE) != 0;
   }
 
@@ skipping 13 matching lines @@
  private:
   Major MajorKey() { return ToBoolean; }
   int MinorKey() { return 0; }
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODEGEN_H_