[builtins] Port Map.p.delete to CSA.

Bug: v8:5717
Change-Id: Iff5b71b9e27b3e4a790118cbd4877b4460d07b1d
Reviewed-on: https://chromium-review.googlesource.com/582810
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46839}

src/bootstrapper.cc

@@ -3028,6 +3028,10 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
         SimpleInstallFunction(prototype, "has", Builtins::kMapHas, 1, true);
     native_context()->set_map_has(*map_has);
 
+    Handle<JSFunction> map_delete = SimpleInstallFunction(
+        prototype, "delete", Builtins::kMapDelete, 1, true);
+    native_context()->set_map_delete(*map_delete);
+
     SimpleInstallFunction(prototype, "clear", Builtins::kMapClear, 0, true);
     Handle<JSFunction> entries = SimpleInstallFunction(
         prototype, "entries", Builtins::kMapPrototypeEntries, 0, true);

src/builtins/builtins-collections-gen.cc

@@ -966,6 +966,64 @@ void CollectionsBuiltinsAssembler::StoreOrderedHashMapNewEntry(
                                  SmiAdd(number_of_elements, SmiConstant(1)));
 }
 
+TF_BUILTIN(MapDelete, CollectionsBuiltinsAssembler) {
+  Node* const receiver = Parameter(Descriptor::kReceiver);
+  Node* key = Parameter(Descriptor::kKey);
+  Node* const context = Parameter(Descriptor::kContext);
+
+  ThrowIfNotInstanceType(context, receiver, JS_MAP_TYPE,
+                         "Map.prototype.delete");
+
+  Node* const table = LoadObjectField(receiver, JSMap::kTableOffset);
+
+  VARIABLE(entry_start_position_or_hash, MachineType::PointerRepresentation(),
+           IntPtrConstant(0));
+  Label entry_found(this), not_found(this);
+
+  TryLookupOrderedHashMapIndex(table, key, context,
+                               &entry_start_position_or_hash, &entry_found,
+                               &not_found);
+
+  BIND(&not_found);
+  Return(FalseConstant());
+
+  BIND(&entry_found);
+  // If we found the entry, mark the entry as deleted.
+  StoreFixedArrayElement(table, entry_start_position_or_hash.value(),
+                         TheHoleConstant(), UPDATE_WRITE_BARRIER,
+                         kPointerSize * OrderedHashMap::kHashTableStartIndex);
+  StoreFixedArrayElement(table, entry_start_position_or_hash.value(),
+                         TheHoleConstant(), UPDATE_WRITE_BARRIER,
+                         kPointerSize * (OrderedHashMap::kHashTableStartIndex +
+                                         OrderedHashMap::kValueOffset));
+
+  // Decrement the number of elements, increment the number of deleted elements.
+  Node* const number_of_elements =
+      SmiSub(LoadObjectField(table, OrderedHashMap::kNumberOfElementsOffset),
+             SmiConstant(1));
+  StoreObjectFieldNoWriteBarrier(table, OrderedHashMap::kNumberOfElementsOffset,
+                                 number_of_elements);
+  Node* const number_of_deleted = SmiAdd(
+      LoadObjectField(table, OrderedHashMap::kNumberOfDeletedElementsOffset),
+      SmiConstant(1));
+  StoreObjectFieldNoWriteBarrier(
+      table, OrderedHashMap::kNumberOfDeletedElementsOffset, number_of_deleted);
+
+  Node* const number_of_buckets =
+      LoadFixedArrayElement(table, OrderedHashMap::kNumberOfBucketsIndex);
+
+  // If there fewer elements than #buckets / 2, shrink the table.
+  Label shrink(this);
+  GotoIf(SmiLessThan(SmiAdd(number_of_elements, number_of_elements),
+                     number_of_buckets),
+         &shrink);
+  Return(TrueConstant());
+
+  BIND(&shrink);
+  CallRuntime(Runtime::kMapShrink, context, receiver);
+  Return(TrueConstant());
+}
+
 TF_BUILTIN(MapPrototypeEntries, CollectionsBuiltinsAssembler) {
   Node* const receiver = Parameter(Descriptor::kReceiver);
   Node* const context = Parameter(Descriptor::kContext);

src/builtins/builtins-definitions.h

@@ -578,6 +578,7 @@ namespace internal {
   TFS(MapLookupHashIndex, kTable, kKey)                                        \
   TFJ(MapConstructor, SharedFunctionInfo::kDontAdaptArgumentsSentinel)         \
   TFJ(MapSet, 2, kKey, kValue)                                                 \
+  TFJ(MapDelete, 1, kKey)                                                      \
   TFJ(MapGet, 1, kKey)                                                         \
   TFJ(MapHas, 1, kKey)                                                         \
   CPP(MapClear)                                                                \

src/js/collection.js

@@ -186,41 +186,10 @@ DEFINE_METHODS(
   }
 );
 
-// Harmony Map
-
-//Set up the non-enumerable functions on the Map prototype object.
-DEFINE_METHODS(
-  GlobalMap.prototype,
-  {
-    delete(key) {
-      if (!IS_MAP(this)) {
-        throw %make_type_error(kIncompatibleMethodReceiver,
-                            'Map.prototype.delete', this);
-      }
-      var table = %_JSCollectionGetTable(this);
-      var numBuckets = ORDERED_HASH_TABLE_BUCKET_COUNT(table);
-      var hash = GetHash(key);
-      var entry = MapFindEntry(table, numBuckets, key, hash);
-      if (entry === NOT_FOUND) return false;
-
-      var nof = ORDERED_HASH_TABLE_ELEMENT_COUNT(table) - 1;
-      var nod = ORDERED_HASH_TABLE_DELETED_COUNT(table) + 1;
-      var index = ORDERED_HASH_MAP_ENTRY_TO_INDEX(entry, numBuckets);
-      FIXED_ARRAY_SET(table, index, %_TheHole());
-      FIXED_ARRAY_SET(table, index + 1, %_TheHole());
-      ORDERED_HASH_TABLE_SET_ELEMENT_COUNT(table, nof);
-      ORDERED_HASH_TABLE_SET_DELETED_COUNT(table, nod);
-      if (nof < (numBuckets >>> 1)) %MapShrink(this);
-      return true;
-    }
-  }
-);
-
 // -----------------------------------------------------------------------
 // Exports
 
 %InstallToContext([
-  "map_delete", GlobalMap.prototype.delete,
   "set_add", GlobalSet.prototype.add,
   "set_delete", GlobalSet.prototype.delete,
 ]);