diff --git a/src/contexts-inl.h b/src/contexts-inl.h
index eb164591e5..30058dc8c9 100644
--- a/src/contexts-inl.h
+++ b/src/contexts-inl.h
@@ -208,7 +208,7 @@ Map* Context::GetInitialJSArrayMap(ElementsKind kind) const {
   if (!IsFastElementsKind(kind)) return nullptr;
   DisallowHeapAllocation no_gc;
   Object* const initial_js_array_map = get(Context::ArrayMapIndex(kind));
-  DCHECK(!initial_js_array_map->IsUndefined(GetIsolate()));
+  DCHECK(!initial_js_array_map->IsUndefined());
   return Map::cast(initial_js_array_map);
 }
 
diff --git a/src/contexts.cc b/src/contexts.cc
index 42f694ccc8..d3e73e507d 100644
--- a/src/contexts.cc
+++ b/src/contexts.cc
@@ -407,7 +407,7 @@ Handle<Object> Context::Lookup(Handle<String> name, ContextLookupFlags flags,
 void Context::AddOptimizedCode(Code* code) {
   DCHECK(IsNativeContext());
   DCHECK(code->kind() == Code::OPTIMIZED_FUNCTION);
-  DCHECK(code->next_code_link()->IsUndefined(GetIsolate()));
+  DCHECK(code->next_code_link()->IsUndefined());
   code->set_next_code_link(get(OPTIMIZED_CODE_LIST));
   set(OPTIMIZED_CODE_LIST, code, UPDATE_WEAK_WRITE_BARRIER);
 }
diff --git a/src/elements.cc b/src/elements.cc
index 5f09ed16f7..dd8c5f8216 100644
--- a/src/elements.cc
+++ b/src/elements.cc
@@ -364,7 +364,7 @@ static void CopyPackedSmiToDoubleElements(FixedArrayBase* from_base,
   for (uint32_t from_end = from_start + static_cast<uint32_t>(packed_size);
        from_start < from_end; from_start++, to_start++) {
     Object* smi = from->get(from_start);
-    DCHECK(!smi->IsTheHole(from->GetIsolate()));
+    DCHECK(!smi->IsTheHole());
     to->set(to_start, Smi::ToInt(smi));
   }
 }
@@ -2582,7 +2582,7 @@ class FastElementsAccessor : public ElementsAccessorBase<Subclass, KindTraits> {
     WriteBarrierMode mode = raw_backing_store->GetWriteBarrierMode(no_gc);
     for (uint32_t i = 0; i < copy_size; i++) {
       Object* argument = (*args)[src_index + i];
-      DCHECK(!argument->IsTheHole(raw_backing_store->GetIsolate()));
+      DCHECK(!argument->IsTheHole());
       Subclass::SetImpl(raw_backing_store, dst_index + i, argument, mode);
     }
   }
@@ -3632,10 +3632,10 @@ class SloppyArgumentsElementsAccessor
       // Store context mapped entry.
       DisallowHeapAllocation no_gc;
       Object* probe = elements->get_mapped_entry(entry);
-      DCHECK(!probe->IsTheHole(store->GetIsolate()));
+      DCHECK(!probe->IsTheHole());
       Context* context = elements->context();
       int context_entry = Smi::ToInt(probe);
-      DCHECK(!context->get(context_entry)->IsTheHole(store->GetIsolate()));
+      DCHECK(!context->get(context_entry)->IsTheHole());
       context->set(context_entry, value);
     } else {
       //  Entry is not context mapped defer to arguments.
@@ -3645,7 +3645,7 @@ class SloppyArgumentsElementsAccessor
         AliasedArgumentsEntry* alias = AliasedArgumentsEntry::cast(current);
         Context* context = elements->context();
         int context_entry = alias->aliased_context_slot();
-        DCHECK(!context->get(context_entry)->IsTheHole(store->GetIsolate()));
+        DCHECK(!context->get(context_entry)->IsTheHole());
         context->set(context_entry, value);
       } else {
         ArgumentsAccessor::SetImpl(arguments, entry - length, value);
diff --git a/src/objects-inl.h b/src/objects-inl.h
index a2233ac3ed..6ea996e804 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -214,6 +214,26 @@ bool HeapObject::IsNullOrUndefined(Isolate* isolate) const {
   return this == heap->null_value() || this == heap->undefined_value();
 }
 
+#ifdef DEBUG
+#define IS_TYPE_FUNCTION_DEF(Type, Value)                                  \
+  bool Object::Is##Type() const {                                          \
+    return IsHeapObject() && HeapObject::cast(this)->Is##Type();           \
+  }                                                                        \
+  bool HeapObject::Is##Type() const {                                      \
+    return IsOddball() && Oddball::cast(this)->kind() == Oddball::k##Type; \
+  }
+ODDBALL_LIST(IS_TYPE_FUNCTION_DEF)
+#undef IS_TYPE_FUNCTION_DEF
+
+bool Object::IsNullOrUndefined() const {
+  return this->IsNull() || this->IsUndefined();
+}
+
+bool HeapObject::IsNullOrUndefined() const {
+  return this->IsNull() || this->IsUndefined();
+}
+#endif
+
 bool HeapObject::IsString() const {
   return map()->instance_type() < FIRST_NONSTRING_TYPE;
 }
@@ -2562,7 +2582,7 @@ Context* JSFunction::native_context() { return context()->native_context(); }
 
 
 void JSFunction::set_context(Object* value) {
-  DCHECK(value->IsUndefined(GetIsolate()) || value->IsContext());
+  DCHECK(value->IsUndefined() || value->IsContext());
   WRITE_FIELD(this, kContextOffset, value);
   WRITE_BARRIER(GetHeap(), this, kContextOffset, value);
 }
@@ -3199,8 +3219,7 @@ int SimpleNumberDictionaryShape::GetMapRootIndex() {
 }
 
 bool NameDictionaryShape::IsMatch(Handle<Name> key, Object* other) {
-  DCHECK(other->IsTheHole(key->GetIsolate()) ||
-         Name::cast(other)->IsUniqueName());
+  DCHECK(other->IsTheHole() || Name::cast(other)->IsUniqueName());
   DCHECK(key->IsUniqueName());
   return *key == other;
 }
@@ -3331,7 +3350,7 @@ Object* OrderedHashTableIterator<Derived, TableType>::CurrentKey() {
   TableType* table(TableType::cast(this->table()));
   int index = Smi::ToInt(this->index());
   Object* key = table->KeyAt(index);
-  DCHECK(!key->IsTheHole(table->GetIsolate()));
+  DCHECK(!key->IsTheHole());
   return key;
 }
 
diff --git a/src/objects.cc b/src/objects.cc
index 2cce8bf3be..456f6b5f2c 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -4336,7 +4336,7 @@ void JSObject::MigrateToMap(Handle<JSObject> object, Handle<Map> new_map,
       // Ensure that no transition was inserted for prototype migrations.
       DCHECK_EQ(0, TransitionsAccessor(old_map->GetIsolate(), old_map)
                        .NumberOfTransitions());
-      DCHECK(new_map->GetBackPointer()->IsUndefined(old_map->GetIsolate()));
+      DCHECK(new_map->GetBackPointer()->IsUndefined());
       DCHECK(object->map() != *old_map);
     }
   } else {
@@ -6160,7 +6160,7 @@ Maybe<bool> JSObject::DefineOwnPropertyIgnoreAttributes(
 MaybeHandle<Object> JSObject::SetOwnPropertyIgnoreAttributes(
     Handle<JSObject> object, Handle<Name> name, Handle<Object> value,
     PropertyAttributes attributes) {
-  DCHECK(!value->IsTheHole(object->GetIsolate()));
+  DCHECK(!value->IsTheHole());
   LookupIterator it(object, name, object, LookupIterator::OWN);
   return DefineOwnPropertyIgnoreAttributes(&it, value, attributes);
 }
@@ -13946,7 +13946,7 @@ void SharedFunctionInfo::InitFromFunctionLiteral(
       lit->requires_instance_fields_initializer());
 
   shared_info->set_is_toplevel(is_toplevel);
-  DCHECK(shared_info->outer_scope_info()->IsTheHole(shared_info->GetIsolate()));
+  DCHECK(shared_info->outer_scope_info()->IsTheHole());
   if (!is_toplevel) {
     Scope* outer_scope = lit->scope()->GetOuterScopeWithContext();
     if (outer_scope) {
diff --git a/src/objects.h b/src/objects.h
index f6bad8da4c..ee175675f0 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1241,6 +1241,16 @@ class Object {
 
   INLINE(bool IsNullOrUndefined(Isolate* isolate) const);
 
+// Non-isolate version of oddball check. This is slower than the above check,
+// so it should only be used for DCHECKS.
+#ifdef DEBUG
+#define IS_TYPE_FUNCTION_DECL(Type, Value) INLINE(bool Is##Type() const);
+  ODDBALL_LIST(IS_TYPE_FUNCTION_DECL)
+#undef IS_TYPE_FUNCTION_DECL
+
+  INLINE(bool IsNullOrUndefined() const);
+#endif
+
   // A non-keyed store is of the form a.x = foo or a["x"] = foo whereas
   // a keyed store is of the form a[expression] = foo.
   enum StoreFromKeyed {
@@ -1820,6 +1830,16 @@ class HeapObject: public Object {
 
   INLINE(bool IsNullOrUndefined(Isolate* isolate) const);
 
+// Non-isolate version of oddball check. This is slower than the above check,
+// so it should only be used for DCHECKS.
+#ifdef DEBUG
+#define IS_TYPE_FUNCTION_DECL(Type, Value) INLINE(bool Is##Type() const);
+  ODDBALL_LIST(IS_TYPE_FUNCTION_DECL)
+#undef IS_TYPE_FUNCTION_DECL
+
+  INLINE(bool IsNullOrUndefined() const);
+#endif
+
 #define DECL_STRUCT_PREDICATE(NAME, Name, name) INLINE(bool Is##Name() const);
   STRUCT_LIST(DECL_STRUCT_PREDICATE)
 #undef DECL_STRUCT_PREDICATE
diff --git a/src/objects/fixed-array-inl.h b/src/objects/fixed-array-inl.h
index 19a88dc767..31459e4fdb 100644
--- a/src/objects/fixed-array-inl.h
+++ b/src/objects/fixed-array-inl.h
@@ -335,7 +335,7 @@ void ArrayList::Set(int index, Object* obj, WriteBarrierMode mode) {
 }
 
 void ArrayList::Clear(int index, Object* undefined) {
-  DCHECK(undefined->IsUndefined(GetIsolate()));
+  DCHECK(undefined->IsUndefined());
   FixedArray::cast(this)->set(kFirstIndex + index, undefined,
                               SKIP_WRITE_BARRIER);
 }
@@ -690,7 +690,7 @@ void FixedTypedArray<Traits>::SetValue(uint32_t index, Object* value) {
   } else {
     // Clamp undefined to the default value. All other types have been
     // converted to a number type further up in the call chain.
-    DCHECK(value->IsUndefined(GetIsolate()));
+    DCHECK(value->IsUndefined());
   }
   set(index, cast_value);
 }
diff --git a/src/objects/js-collection-inl.h b/src/objects/js-collection-inl.h
index 12c8bd23f4..12bba94eaa 100644
--- a/src/objects/js-collection-inl.h
+++ b/src/objects/js-collection-inl.h
@@ -31,7 +31,7 @@ Object* JSMapIterator::CurrentValue() {
   OrderedHashMap* table(OrderedHashMap::cast(this->table()));
   int index = Smi::ToInt(this->index());
   Object* value = table->ValueAt(index);
-  DCHECK(!value->IsTheHole(table->GetIsolate()));
+  DCHECK(!value->IsTheHole());
   return value;
 }
 
diff --git a/src/objects/map-inl.h b/src/objects/map-inl.h
index d23d55129d..1d9f880e92 100644
--- a/src/objects/map-inl.h
+++ b/src/objects/map-inl.h
@@ -529,7 +529,7 @@ bool Map::IsJSDataViewMap() const {
 Object* Map::prototype() const { return READ_FIELD(this, kPrototypeOffset); }
 
 void Map::set_prototype(Object* value, WriteBarrierMode mode) {
-  DCHECK(value->IsNull(GetIsolate()) || value->IsJSReceiver());
+  DCHECK(value->IsNull() || value->IsJSReceiver());
   WRITE_FIELD(this, kPrototypeOffset, value);
   CONDITIONAL_WRITE_BARRIER(GetHeap(), this, kPrototypeOffset, value, mode);
 }
@@ -711,7 +711,7 @@ bool Map::IsInobjectSlackTrackingInProgress() const {
 
 void Map::InobjectSlackTrackingStep() {
   // Slack tracking should only be performed on an initial map.
-  DCHECK(GetBackPointer()->IsUndefined(GetIsolate()));
+  DCHECK(GetBackPointer()->IsUndefined());
   if (!IsInobjectSlackTrackingInProgress()) return;
   int counter = construction_counter();
   set_construction_counter(counter - 1);
diff --git a/src/objects/module.cc b/src/objects/module.cc
index 695d2eec55..0d108a141f 100644
--- a/src/objects/module.cc
+++ b/src/objects/module.cc
@@ -274,7 +274,7 @@ void Module::RecordError() {
 Object* Module::GetException() {
   DisallowHeapAllocation no_alloc;
   DCHECK_EQ(status(), Module::kErrored);
-  DCHECK(!exception()->IsTheHole(GetIsolate()));
+  DCHECK(!exception()->IsTheHole());
   return exception();
 }
 
diff --git a/src/objects/shared-function-info-inl.h b/src/objects/shared-function-info-inl.h
index 448cdbf88f..ef60d0081c 100644
--- a/src/objects/shared-function-info-inl.h
+++ b/src/objects/shared-function-info-inl.h
@@ -365,8 +365,8 @@ ScopeInfo* SharedFunctionInfo::GetOuterScopeInfo() const {
 void SharedFunctionInfo::set_outer_scope_info(HeapObject* value,
                                               WriteBarrierMode mode) {
   DCHECK(!is_compiled());
-  DCHECK(raw_outer_scope_info_or_feedback_metadata()->IsTheHole(GetIsolate()));
-  DCHECK(value->IsScopeInfo() || value->IsTheHole(GetIsolate()));
+  DCHECK(raw_outer_scope_info_or_feedback_metadata()->IsTheHole());
+  DCHECK(value->IsScopeInfo() || value->IsTheHole());
   return set_raw_outer_scope_info_or_feedback_metadata(value, mode);
 }
 
@@ -545,13 +545,12 @@ String* SharedFunctionInfo::inferred_name() {
   if (HasInferredName()) {
     return String::cast(function_identifier());
   }
-  DCHECK(function_identifier()->IsUndefined(GetIsolate()) ||
-         HasBuiltinFunctionId());
+  DCHECK(function_identifier()->IsUndefined() || HasBuiltinFunctionId());
   return GetHeap()->empty_string();
 }
 
 void SharedFunctionInfo::set_inferred_name(String* inferred_name) {
-  DCHECK(function_identifier()->IsUndefined(GetIsolate()) || HasInferredName());
+  DCHECK(function_identifier()->IsUndefined() || HasInferredName());
   set_function_identifier(inferred_name);
 }
 
diff --git a/src/snapshot/partial-serializer.cc b/src/snapshot/partial-serializer.cc
index 8b4c9d8d92..f4009eceba 100644
--- a/src/snapshot/partial-serializer.cc
+++ b/src/snapshot/partial-serializer.cc
@@ -37,7 +37,7 @@ void PartialSerializer::Serialize(Context** o, bool include_global_proxy) {
   // explicitly when it's loaded.
   context_->set(Context::NEXT_CONTEXT_LINK,
                 isolate()->heap()->undefined_value());
-  DCHECK(!context_->global_object()->IsUndefined(context_->GetIsolate()));
+  DCHECK(!context_->global_object()->IsUndefined());
   // Reset math random cache to get fresh random numbers.
   context_->set_math_random_index(Smi::kZero);
   context_->set_math_random_cache(isolate()->heap()->undefined_value());
diff --git a/src/wasm/wasm-debug.cc b/src/wasm/wasm-debug.cc
index b00d106e98..7f4b1206f5 100644
--- a/src/wasm/wasm-debug.cc
+++ b/src/wasm/wasm-debug.cc
@@ -544,7 +544,7 @@ wasm::InterpreterHandle* GetOrCreateInterpreterHandle(
 
 wasm::InterpreterHandle* GetInterpreterHandle(WasmDebugInfo* debug_info) {
   Object* handle_obj = debug_info->interpreter_handle();
-  DCHECK(!handle_obj->IsUndefined(debug_info->GetIsolate()));
+  DCHECK(!handle_obj->IsUndefined());
   return Managed<wasm::InterpreterHandle>::cast(handle_obj)->raw();
 }