Improve elements validation and object printing

src/objects-printer.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/objects.h"
 
 #include "src/disasm.h"
 #include "src/disassembler.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/objects-inl.h"
@@ skipping 15 matching lines @@
 void Object::Print(std::ostream& os) {  // NOLINT
   if (IsSmi()) {
     Smi::cast(this)->SmiPrint(os);
   } else {
     HeapObject::cast(this)->HeapObjectPrint(os);
   }
 }
 
 
 void HeapObject::PrintHeader(std::ostream& os, const char* id) {  // NOLINT
-  os << reinterpret_cast<void*>(this) << ": [" << id << "]";
+  os << reinterpret_cast<void*>(this) << ": [";
+  if (id != nullptr) {
+    os << id;
+  } else {
+    os << map()->instance_type();
+  }
+  os << "]";
 }
 
 
 void HeapObject::HeapObjectPrint(std::ostream& os) {  // NOLINT
   InstanceType instance_type = map()->instance_type();
 
   HandleScope scope(GetIsolate());
   if (instance_type < FIRST_NONSTRING_TYPE) {
     String::cast(this)->StringPrint(os);
     return;
@@ skipping 43 matching lines @@
 
     TYPED_ARRAYS(PRINT_FIXED_TYPED_ARRAY)
 #undef PRINT_FIXED_TYPED_ARRAY
 
     case FILLER_TYPE:
       os << "filler";
       break;
     case JS_OBJECT_TYPE:  // fall through
     case JS_SPECIAL_API_OBJECT_TYPE:
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
-    case JS_ARRAY_TYPE:
     case JS_GENERATOR_OBJECT_TYPE:
     case JS_PROMISE_TYPE:
       JSObject::cast(this)->JSObjectPrint(os);
       break;
+    case JS_ARRAY_TYPE:
+      JSArray::cast(this)->JSArrayPrint(os);
+      break;
     case JS_REGEXP_TYPE:
       JSRegExp::cast(this)->JSRegExpPrint(os);
       break;
     case ODDBALL_TYPE:
       Oddball::cast(this)->to_string()->Print(os);
       break;
     case JS_MODULE_TYPE:
       JSModule::cast(this)->JSModulePrint(os);
       break;
     case JS_BOUND_FUNCTION_TYPE:
@@ skipping 274 matching lines @@
       break;
   }
 }
 
 
 static void JSObjectPrintHeader(std::ostream& os, JSObject* obj,
                                 const char* id) {  // NOLINT
   obj->PrintHeader(os, id);
   // Don't call GetElementsKind, its validation code can cause the printer to
   // fail when debugging.
-  os << "\n - map = " << reinterpret_cast<void*>(obj->map()) << " ["
+  os << "\n - map = " << reinterpret_cast<void*>(obj->map()) << " [";
+  if (obj->HasFastProperties()) {
+    os << "FastProperties";
+  } else {
+    os << "DictionaryProperties";
+  }
+  PrototypeIterator iter(obj->GetIsolate(), obj);
+  os << "]\n - prototype = " << reinterpret_cast<void*>(iter.GetCurrent());
+  os << "\n - elements = " << Brief(obj->elements()) << " ["
      << ElementsKindToString(obj->map()->elements_kind());
   if (obj->elements()->map() == obj->GetHeap()->fixed_cow_array_map()) {
     os << " (COW)";
   }
-  PrototypeIterator iter(obj->GetIsolate(), obj);
-  os << "]\n - prototype = " << reinterpret_cast<void*>(iter.GetCurrent());
-  if (obj->elements()->length() > 0) {
-    os << "\n - elements = " << Brief(obj->elements());
-  }
+  os << "]";
 }
 
 
 static void JSObjectPrintBody(std::ostream& os, JSObject* obj,  // NOLINT
                               bool print_elements = true) {
   os << "\n {";
   obj->PrintProperties(os);
-  obj->PrintTransitions(os);
   if (print_elements) obj->PrintElements(os);
   os << "\n }\n";
 }
 
 
 void JSObject::JSObjectPrint(std::ostream& os) {  // NOLINT
-  JSObjectPrintHeader(os, this, "JSObject");
+  JSObjectPrintHeader(os, this, nullptr);
   JSObjectPrintBody(os, this);
 }
 
+void JSArray::JSArrayPrint(std::ostream& os) {  // NOLINT
+  JSObjectPrintHeader(os, this, "JSArray");
+  os << "\n - length = " << Brief(this->length());
+  JSObjectPrintBody(os, this);
+}
+
 
 void JSRegExp::JSRegExpPrint(std::ostream& os) {  // NOLINT
   JSObjectPrintHeader(os, this, "JSRegExp");
   os << "\n - data = " << Brief(data());
   JSObjectPrintBody(os, this);
 }
 
 
 void JSModule::JSModulePrint(std::ostream& os) {  // NOLINT
   JSObjectPrintHeader(os, this, "JSModule");
@@ skipping 835 matching lines @@
 
 void TransitionArray::PrintTransitions(std::ostream& os, Object* transitions,
                                        bool print_header) {  // NOLINT
   int num_transitions = NumberOfTransitions(transitions);
   if (print_header) {
     os << "Transition array #" << num_transitions << ":";
   }
   for (int i = 0; i < num_transitions; i++) {
     Name* key = GetKey(transitions, i);
     Map* target = GetTarget(transitions, i);
-    os << "\n   ";
+    os << "\n     ";
 #ifdef OBJECT_PRINT
     key->NamePrint(os);
 #else
     key->ShortPrint(os);
 #endif
     os << ": ";
     Heap* heap = key->GetHeap();
     if (key == heap->nonextensible_symbol()) {
       os << "(transition to non-extensible)";
     } else if (key == heap->sealed_symbol()) {
@@ skipping 29 matching lines @@
 void JSObject::PrintTransitions(std::ostream& os) {  // NOLINT
   Object* transitions = map()->raw_transitions();
   int num_transitions = TransitionArray::NumberOfTransitions(transitions);
   if (num_transitions == 0) return;
   os << "\n - transitions";
   TransitionArray::PrintTransitions(os, transitions, false);
 }
 #endif  // defined(DEBUG) || defined(OBJECT_PRINT)
 }  // namespace internal
 }  // namespace v8