Fastpath some spread-call desugaring.

src/parsing/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/parsing/parser.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/ast/ast-expression-rewriter.h"
@@ skipping 3943 matching lines @@
   if (list->length() == 1) {
     // Spread-call with single spread argument produces an InternalArray
     // containing the values from the array.
     //
     // Function is called or constructed with the produced array of arguments
     //
     // EG: Apply(Func, Spread(spread0))
     ZoneList<Expression*>* spread_list =
         new (zone()) ZoneList<Expression*>(0, zone());
     spread_list->Add(list->at(0)->AsSpread()->expression(), zone());
-    args->Add(factory()->NewCallRuntime(Context::SPREAD_ITERABLE_INDEX,
+    args->Add(factory()->NewCallRuntime(Runtime::kSpreadIterablePrepare,
                                         spread_list, kNoSourcePosition),
               zone());
     return args;
   } else {
     // Spread-call with multiple arguments produces array literals for each
     // sequences of unspread arguments, and converts each spread iterable to
     // an Internal array. Finally, all of these produced arrays are flattened
     // into a single InternalArray, containing the arguments for the call.
     //
     // EG: Apply(Func, Flatten([unspread0, unspread1], Spread(spread0),
@@ skipping 1425 matching lines @@
 
   return final_loop;
 }
 
 #undef CHECK_OK
 #undef CHECK_OK_VOID
 #undef CHECK_FAILED
 
 }  // namespace internal
 }  // namespace v8