Revert "Inline instance object hash code into object header on 64 bit."

runtime/vm/assembler_x64.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_VM_ASSEMBLER_X64_H_
 #define RUNTIME_VM_ASSEMBLER_X64_H_
 
 #ifndef RUNTIME_VM_ASSEMBLER_H_
 #error Do not include assembler_x64.h directly; use assembler.h instead.
 #endif
@@ skipping 672 matching lines @@
   void j(Condition condition, Label* label, bool near = kFarJump);
 
   void jmp(Register reg);
   void jmp(const Address& address);
   void jmp(Label* label, bool near = kFarJump);
   void jmp(const ExternalLabel* label);
   void jmp(const StubEntry& stub_entry);
 
   void lock();
   void cmpxchgl(const Address& address, Register reg);
+  void lock_cmpxchgl(const Address& address, Register reg) {
+    lock();
+    cmpxchgl(address, reg);
+  }
 
   void cmpxchgq(const Address& address, Register reg);
+  void lock_cmpxchgq(const Address& address, Register reg) {
+    lock();
+    cmpxchgq(address, reg);
+  }
 
   void cpuid();
 
   // Issue memory to memory move through a TMP register.
   // TODO(koda): Assert that these are not used for heap objects.
   void MoveMemoryToMemory(const Address& dst, const Address& src) {
     movq(TMP, src);
     movq(dst, TMP);
   }
 
@@ skipping 81 matching lines @@
   void DoubleNegate(XmmRegister d);
   void FloatNegate(XmmRegister f);
 
   void DoubleAbs(XmmRegister reg);
 
   void LockCmpxchgq(const Address& address, Register reg) {
     lock();
     cmpxchgq(address, reg);
   }
 
-  void LockCmpxchgl(const Address& address, Register reg) {
-    lock();
-    cmpxchgl(address, reg);
-  }
-
   void PushRegisters(intptr_t cpu_register_set, intptr_t xmm_register_set);
   void PopRegisters(intptr_t cpu_register_set, intptr_t xmm_register_set);
 
   void CheckCodePointer();
 
   void EnterFrame(intptr_t frame_space);
   void LeaveFrame();
   void ReserveAlignedFrameSpace(intptr_t frame_space);
 
   // Create a frame for calling into runtime that preserves all volatile
@@ skipping 335 matching lines @@
 }
 
 
 inline void Assembler::EmitOperandSizeOverride() {
   EmitUint8(0x66);
 }
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_ASSEMBLER_X64_H_