Add pshufw instruction, fix inconsistencies with pextrw instruction.

src/x64/assembler-x64.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 871 matching lines @@
   void clc();
   void cld();
   void cpuid();
   void hlt();
   void int3();
   void nop();
   void ret(int imm16);
   void ud2();
   void setcc(Condition cc, Register reg);
 
+  void pshufw(XMMRegister dst, XMMRegister src, uint8_t shuffle);
+  void pshufw(XMMRegister dst, const Operand& src, uint8_t shuffle);
+
   // Label operations & relative jumps (PPUM Appendix D)
   //
   // Takes a branch opcode (cc) and a label (L) and generates
   // either a backward branch or a forward branch and links it
   // to the label fixup chain. Usage:
   //
   // Label L;    // unbound label
   // j(cc, &L);  // forward branch to unbound label
   // bind(&L);   // bind label to the current pc
   // j(cc, &L);  // backward branch to bound label
@@ skipping 1617 matching lines @@
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_X64_ASSEMBLER_X64_H_