Copy-on-write arrays.

src/arm/full-codegen-arm.cc

Index: src/arm/full-codegen-arm.cc
diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index b58a4a5854a6b77b050797bfa4605a0cc4b58e95..9e5e8e8b5127381b14e4480b298421d2f1dc5577 100644
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -1223,12 +1223,17 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
   __ mov(r2, Operand(Smi::FromInt(expr->literal_index())));
   __ mov(r1, Operand(expr->constant_elements()));
   __ Push(r3, r2, r1);
-  if (expr->depth() > 1) {
+  if (expr->constant_elements()->map() == Heap::fixed_cow_array_map()) {
+    FastCloneShallowArrayStub stub(
+        FastCloneShallowArrayStub::COPY_ON_WRITE_ELEMENTS, length);
+    __ CallStub(&stub);
+  } else if (expr->depth() > 1) {
     __ CallRuntime(Runtime::kCreateArrayLiteral, 3);
-  } else if (length > FastCloneShallowArrayStub::kMaximumLength) {
+  } else if (length > FastCloneShallowArrayStub::kMaximumClonedLength) {
     __ CallRuntime(Runtime::kCreateArrayLiteralShallow, 3);
   } else {
-    FastCloneShallowArrayStub stub(length);
+    FastCloneShallowArrayStub stub(
+        FastCloneShallowArrayStub::CLONE_ELEMENTS, length);
     __ CallStub(&stub);
   }