ARM, ARM64: Optimize array copy

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index e3b85bee07f95fa7ff8359518f243ba7dea24b86..6086e23f687de3390e0575ec8e2dfb7587743152 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -2173,6 +2173,18 @@ LInstruction* LChunkBuilder::DoLoadKeyedGeneric(HLoadKeyedGeneric* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoFillElements(HFillElements* instr) {
+  UNIMPLEMENTED();
+  return NULL;
+}
+
+
+LInstruction* LChunkBuilder::DoCopyElements(HCopyElements* instr) {
+  UNIMPLEMENTED();
+  return NULL;
+}
+
+
 LInstruction* LChunkBuilder::DoStoreKeyed(HStoreKeyed* instr) {
   ElementsKind elements_kind = instr->elements_kind();