Fix usage of literal cloning for large double arrays.

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 41fc8eaf3e38df11d5413ad0c047275a54990d40..1e35bf406d00a9228bd0d3fa9bb7eb2d66ff3005 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -19,6 +19,7 @@ namespace v8 {
 namespace internal {
 
 // Forward declarations.
+class ArrayLiteral;
 class CodeStubAssembler;
 class ObjectLiteral;
 namespace compiler {
@@ -923,6 +924,11 @@ class FastCloneRegExpStub final : public TurboFanCodeStub {
 
 class FastCloneShallowArrayStub : public TurboFanCodeStub {
  public:
+  // Maximum number of elements in copied array (chosen so that even an array
+  // backed by a double backing store will fit into new-space).
+  static const int kMaximumClonedElements =
+      JSArray::kInitialMaxFastElementArray * kPointerSize / kDoubleSize;
+
   FastCloneShallowArrayStub(Isolate* isolate,
                             AllocationSiteMode allocation_site_mode)
       : TurboFanCodeStub(isolate) {
@@ -936,6 +942,8 @@ class FastCloneShallowArrayStub : public TurboFanCodeStub {
                                   compiler::CodeAssemblerLabel* call_runtime,
                                   AllocationSiteMode allocation_site_mode);
 
+  static bool IsSupported(ArrayLiteral* expr);
+
   AllocationSiteMode allocation_site_mode() const {
     return AllocationSiteModeBits::decode(minor_key_);
   }