Optimize Map/Set.prototype.forEach

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index 4d895db43323dd06b6dd7fe77dd106d069e42e25..aaf8b1838cf9d93f26bb96ab32e1c895efe8b333 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -1610,6 +1610,31 @@ RUNTIME_FUNCTION(Runtime_SetIteratorNext) {
 }
 
 
+RUNTIME_FUNCTION(Runtime_SetIteratorCurrentKey) {
+  SealHandleScope shs(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSSetIterator, holder, 0);

[adamk, 2014/06/16 22:13:57]

This should just be CONVERT_ARG_CHECKED() (no "HANDLE") now.

+  return holder->CurrentKey();
+}
+
+
+RUNTIME_FUNCTION(Runtime_SetIteratorHasMore) {
+  HandleScope scope(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSSetIterator, holder, 0);
+  return isolate->heap()->ToBoolean(JSSetIterator::HasMore(holder));
+}
+
+
+RUNTIME_FUNCTION(Runtime_SetIteratorMoveNext) {
+  SealHandleScope shs(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSSetIterator, holder, 0);
+  holder->MoveNext();
+  return isolate->heap()->undefined_value();
+}
+
+
 RUNTIME_FUNCTION(Runtime_MapInitialize) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 1);
@@ -1714,6 +1739,39 @@ RUNTIME_FUNCTION(Runtime_MapIteratorNext) {
 }
 
 
+RUNTIME_FUNCTION(Runtime_MapIteratorCurrentKey) {
+  SealHandleScope shs(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSMapIterator, holder, 0);

[adamk, 2014/06/16 22:13:57]

ditto, and lots more below.

Basically, SealHandleScope should be paired with CONVERT_ARG_CHECKED(), while
HandleScope should be paired with CONVERT_ARG_HANDLE_CHECKED(). Similarly, if
your Runtime function uses Handles at all, it should have a HandleScope, not a
SealHandleScope.

V8 folks, please correct me if I'm providing poor advice here. My understanding
is that V8's not abandoning raw pointers altogether, only in those cases that
previously required MaybeObjects.

+  return holder->CurrentKey();
+}
+
+
+RUNTIME_FUNCTION(Runtime_MapIteratorCurrentValue) {
+  SealHandleScope shs(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSMapIterator, holder, 0);
+  return holder->CurrentValue();
+}
+
+
+RUNTIME_FUNCTION(Runtime_MapIteratorHasMore) {
+  HandleScope scope(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSMapIterator, holder, 0);
+  return isolate->heap()->ToBoolean(JSMapIterator::HasMore(holder));
+}
+
+
+RUNTIME_FUNCTION(Runtime_MapIteratorMoveNext) {
+  SealHandleScope shs(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSMapIterator, holder, 0);
+  holder->MoveNext();
+  return isolate->heap()->undefined_value();
+}
+
+
 static Handle<JSWeakCollection> WeakCollectionInitialize(
     Isolate* isolate,
     Handle<JSWeakCollection> weak_collection) {