Use shorting encoding for mov reg, imm.

src/assembler-ia32.h

Index: src/assembler-ia32.h
diff --git a/src/assembler-ia32.h b/src/assembler-ia32.h
index 579e4c215633e15df632bc4bdf36a9c0109c9332..9647446e7040a80e63021b20be855f4e16f2ac90 100644
--- a/src/assembler-ia32.h
+++ b/src/assembler-ia32.h
@@ -453,8 +453,10 @@ class Assembler : public Malloced {
   void mov_w(const Operand& dst, Register src);
 
   void mov(Register dst, int32_t imm32);
+  void mov(Register dst, const Immediate& x);
   void mov(Register dst, Handle<Object> handle);
   void mov(Register dst, const Operand& src);
+  void mov(Register dst, Register src);
   void mov(const Operand& dst, const Immediate& x);
   void mov(const Operand& dst, Handle<Object> handle);
   void mov(const Operand& dst, Register src);