Introduce IsUndefined(Isolate*) and IsTheHole(Isolate*)

src/runtime/runtime-strings.cc

 // Copyright 2014 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/regexp/jsregexp-inl.h"
 #include "src/string-builder.h"
 #include "src/string-search.h"
@@ skipping 707 matching lines @@
 
 
 // Copies Latin1 characters to the given fixed array looking up
 // one-char strings in the cache. Gives up on the first char that is
 // not in the cache and fills the remainder with smi zeros. Returns
 // the length of the successfully copied prefix.
 static int CopyCachedOneByteCharsToArray(Heap* heap, const uint8_t* chars,
                                          FixedArray* elements, int length) {
   DisallowHeapAllocation no_gc;
   FixedArray* one_byte_cache = heap->single_character_string_cache();
-  Object* undefined = heap->undefined_value();
   int i;
   WriteBarrierMode mode = elements->GetWriteBarrierMode(no_gc);
   for (i = 0; i < length; ++i) {
     Object* value = one_byte_cache->get(chars[i]);
-    if (value == undefined) break;
+    if (value->IsUndefined(heap->isolate())) break;
     elements->set(i, value, mode);
   }
   if (i < length) {
     DCHECK(Smi::FromInt(0) == 0);
     memset(elements->data_start() + i, 0, kPointerSize * (length - i));
   }
 #ifdef DEBUG
   for (int j = 0; j < length; ++j) {
     Object* element = elements->get(j);
     DCHECK(element == Smi::FromInt(0) ||
@@ skipping 463 matching lines @@
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 2);
   if (!args[0]->IsString()) return isolate->heap()->undefined_value();
   if (!args[1]->IsNumber()) return isolate->heap()->undefined_value();
   if (std::isinf(args.number_at(1))) return isolate->heap()->nan_value();
   return __RT_impl_Runtime_StringCharCodeAtRT(args, isolate);
 }
 
 }  // namespace internal
 }  // namespace v8