Enable code generation for array literals.

Introduce macro assembler support for pushing heap-object handles and
for comparing a register to a heap-object handle.

Cleanup: Remove some code that was needlessly commented out.  Added
TODO's for code that was commented out (where we do not hit an
UNIMPLEMENTED). 
Review URL: http://codereview.chromium.org/140060

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2241 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/macro-assembler-x64.cc

@@ -45,6 +45,14 @@ MacroAssembler::MacroAssembler(void* buffer, int size)
 }
 
 
+// TODO(x64): For now, the write barrier is disabled on x64 and we
+// therefore generate no code.  This should be fixed when the write
+// barrier is enabled.
+void MacroAssembler::RecordWrite(Register object, int offset,
+                                 Register value, Register scratch) {
+}
+
+
 void MacroAssembler::Assert(Condition cc, const char* msg) {
   if (FLAG_debug_code) Check(cc, msg);
 }
@@ -301,6 +309,12 @@ void MacroAssembler::Cmp(Register dst, Handle<Object> source) {
 }
 
 
+void MacroAssembler::Push(Handle<Object> source) {
+  Move(kScratchRegister, source);
+  push(kScratchRegister);
+}
+
+
 void MacroAssembler::Jump(ExternalReference ext) {
   movq(kScratchRegister, ext);
   jmp(kScratchRegister);

src/x64/macro-assembler-x64.h

@@ -172,6 +172,7 @@ class MacroAssembler: public Assembler {
   void Move(Register dst, Handle<Object> source);
   void Move(const Operand& dst, Handle<Object> source);
   void Cmp(Register dst, Handle<Object> source);
+  void Push(Handle<Object> source);
 
   // Control Flow
   void Jump(Address destination, RelocInfo::Mode rmode);