[builtins] implement JSBuiltinReducer for ArrayIteratorNext()

src/compiler/access-builder.cc

Index: src/compiler/access-builder.cc
diff --git a/src/compiler/access-builder.cc b/src/compiler/access-builder.cc
index 530143440d52e4726bbceeabc2fe495023c7886e..a92e834d52158cb990eeb2a3139976cbf620ac2c 100644
--- a/src/compiler/access-builder.cc
+++ b/src/compiler/access-builder.cc
@@ -549,6 +549,57 @@ FieldAccess AccessBuilder::ForJSGlobalObjectNativeContext() {
 }
 
 // static
+FieldAccess AccessBuilder::ForJSArrayIteratorObject() {
+  FieldAccess access = {kTaggedBase,
+                        JSArrayIterator::kIteratedObjectOffset,
+                        Handle<Name>(),
+                        Type::Receiver(),

[Benedikt Meurer, 2016/11/08 08:30:00]

Since you store undefined when done, this type must be ReceiverOrUndefined

[caitp, 2016/11/08 17:53:07]

I had originally added a ReceiverOrUndefined definition to types.h, since one
didn't seem to exist yet. I guess I'll add it back

+                        MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForJSArrayIteratorIndex(InstanceType instance_type,
+                                                   ElementsKind elements_kind) {
+  FieldAccess access = {kTaggedBase,
+                        JSArrayIterator::kNextIndexOffset,
+                        Handle<Name>(),
+                        TypeCache::Get().kPositiveSafeInteger,
+                        MachineType::AnyTagged(),
+                        kFullWriteBarrier};
+  if (instance_type == JS_ARRAY_TYPE) {
+    if (IsFastDoubleElementsKind(elements_kind)) {
+      access.type = TypeCache::Get().kFixedDoubleArrayLengthType;
+      access.machine_type = MachineType::TaggedSigned();
+      access.write_barrier_kind = kNoWriteBarrier;
+    } else if (IsFastElementsKind(elements_kind)) {
+      access.type = TypeCache::Get().kFixedArrayLengthType;
+      access.machine_type = MachineType::TaggedSigned();
+      access.write_barrier_kind = kNoWriteBarrier;
+    } else {
+      access.type = TypeCache::Get().kJSArrayLengthType;
+    }
+  } else if (instance_type == JS_TYPED_ARRAY_TYPE) {
+    access.type = TypeCache::Get().kJSTypedArrayLengthType;
+    access.machine_type = MachineType::TaggedSigned();
+    access.write_barrier_kind = kNoWriteBarrier;
+  }
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForJSArrayIteratorObjectMap() {
+  FieldAccess access = {kTaggedBase,
+                        JSArrayIterator::kIteratedObjectMapOffset,
+                        Handle<Name>(),
+                        Type::OtherInternal(),
+                        MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
+  return access;
+}
+
+// static
 FieldAccess AccessBuilder::ForJSStringIteratorString() {
   FieldAccess access = {
       kTaggedBase,    JSStringIterator::kStringOffset, Handle<Name>(),