Make closures optimizable by Crankshaft compiler.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 5b3f23bb022663860c6019bb6239ef059ebf6c50..33c76042db6c0fba3501080c2c3e8e86659edd48 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -1404,6 +1404,27 @@ void LCodeGen::DoStoreGlobal(LStoreGlobal* instr) {
 }
 
 
+void LCodeGen::DoLoadContextSlot(LLoadContextSlot* instr) {
+#if 0
+  // TODO(antonm): load a context with a separate instruction.
+  Register result = ToRegister(instr->result());
+  HLoadContextSlot* hinstr = instr->hydrogen();
+  Handle<Context> context = hinstr->context();
+  Comment(";;; Load context slot %d out of %p", hinstr->index(), *context);
+  if (Heap::InNewSpace(*context)) {
+    Handle<JSGlobalPropertyCell> cell =
+        Factory::NewJSGlobalPropertyCell(context);
+    __ mov(result, Operand::Cell(cell));
+  } else {
+    __ mov(result, context);
+  }
+  __ mov(result, Operand(result, Context::SlotOffset(hinstr->index())));
+#else
+  Abort("DoLoadContextSlot unimplemented");
+#endif
+}
+
+
 void LCodeGen::DoLoadNamedField(LLoadNamedField* instr) {
   Abort("DoLoadNamedField unimplemented.");
 }