Ensure object literal element boilerplates aren't modified.

src/arm64/full-codegen-arm64.cc

Index: src/arm64/full-codegen-arm64.cc
diff --git a/src/arm64/full-codegen-arm64.cc b/src/arm64/full-codegen-arm64.cc
index 015ec188cd8164f4a2f5d2544f462f11f7d11caa..9feac938b5320c7d3e14b52e47d0f7aae9c5a9cd 100644
--- a/src/arm64/full-codegen-arm64.cc
+++ b/src/arm64/full-codegen-arm64.cc
@@ -1677,23 +1677,13 @@ void FullCodeGenerator::VisitObjectLiteral(ObjectLiteral* expr) {
   __ Ldr(x3, FieldMemOperand(x3, JSFunction::kLiteralsOffset));
   __ Mov(x2, Smi::FromInt(expr->literal_index()));
   __ Mov(x1, Operand(constant_properties));
-  int flags = expr->fast_elements()
-      ? ObjectLiteral::kFastElements
-      : ObjectLiteral::kNoFlags;
-  flags |= expr->has_function()
-      ? ObjectLiteral::kHasFunction
-      : ObjectLiteral::kNoFlags;
+  int flags = expr->ComputeFlags();
   __ Mov(x0, Smi::FromInt(flags));
-  int properties_count = constant_properties->length() / 2;
-  const int max_cloned_properties =
-      FastCloneShallowObjectStub::kMaximumClonedProperties;
-  if (expr->may_store_doubles() || expr->depth() > 1 ||
-      masm()->serializer_enabled() || flags != ObjectLiteral::kFastElements ||
-      properties_count > max_cloned_properties) {
+  if (MustCreateObjectLiteralWithRuntime(expr)) {
     __ Push(x3, x2, x1, x0);
     __ CallRuntime(Runtime::kCreateObjectLiteral, 4);
   } else {
-    FastCloneShallowObjectStub stub(isolate(), properties_count);
+    FastCloneShallowObjectStub stub(isolate(), expr->properties_count());
     __ CallStub(&stub);
   }
   PrepareForBailoutForId(expr->CreateLiteralId(), TOS_REG);
@@ -1885,18 +1875,9 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
   Comment cmnt(masm_, "[ ArrayLiteral");
 
   expr->BuildConstantElements(isolate());
-  int flags = (expr->depth() == 1) ? ArrayLiteral::kShallowElements
-                                   : ArrayLiteral::kNoFlags;
-
-  ZoneList<Expression*>* subexprs = expr->values();
-  int length = subexprs->length();
   Handle<FixedArray> constant_elements = expr->constant_elements();
-  DCHECK_EQ(2, constant_elements->length());
-  ElementsKind constant_elements_kind =
-      static_cast<ElementsKind>(Smi::cast(constant_elements->get(0))->value());
-  bool has_fast_elements = IsFastObjectElementsKind(constant_elements_kind);
-  Handle<FixedArrayBase> constant_elements_values(
-      FixedArrayBase::cast(constant_elements->get(1)));
+  bool has_fast_elements =
+      IsFastObjectElementsKind(expr->constant_elements_kind());
 
   AllocationSiteMode allocation_site_mode = TRACK_ALLOCATION_SITE;
   if (has_fast_elements && !FLAG_allocation_site_pretenuring) {
@@ -1909,8 +1890,8 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
   __ Ldr(x3, FieldMemOperand(x3, JSFunction::kLiteralsOffset));
   __ Mov(x2, Smi::FromInt(expr->literal_index()));
   __ Mov(x1, Operand(constant_elements));
-  if (expr->depth() > 1 || length > JSObject::kInitialMaxFastElementArray) {
-    __ Mov(x0, Smi::FromInt(flags));
+  if (MustCreateArrayLiteralWithRuntime(expr)) {
+    __ Mov(x0, Smi::FromInt(expr->ComputeFlags()));
     __ Push(x3, x2, x1, x0);
     __ CallRuntime(Runtime::kCreateArrayLiteral, 4);
   } else {
@@ -1920,6 +1901,8 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
   PrepareForBailoutForId(expr->CreateLiteralId(), TOS_REG);
 
   bool result_saved = false;  // Is the result saved to the stack?
+  ZoneList<Expression*>* subexprs = expr->values();
+  int length = subexprs->length();
 
   // Emit code to evaluate all the non-constant subexpressions and to store
   // them into the newly cloned array.
@@ -1936,7 +1919,7 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
     }
     VisitForAccumulatorValue(subexpr);
 
-    if (IsFastObjectElementsKind(constant_elements_kind)) {
+    if (has_fast_elements) {
       int offset = FixedArray::kHeaderSize + (i * kPointerSize);
       __ Peek(x6, kPointerSize);  // Copy of array literal.
       __ Ldr(x1, FieldMemOperand(x6, JSObject::kElementsOffset));