[builtins] Move IterableToList to iterator-gen

... So that this can be re-used in the intl code. Also, add a helper
method that loads the iterator if it's not provided.

Bug: v8:5751
Change-Id: Ifc1142a486b2cdf1c33a813c5446b206ad9f81ef
Reviewed-on: https://chromium-review.googlesource.com/1156390
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54819}

src/builtins/builtins-iterator-gen.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "src/builtins/builtins-iterator-gen.h"
+#include "src/builtins/growable-fixed-array-gen.h"
 
 #include "src/heap/factory-inl.h"
 
@@ -11,8 +12,8 @@ namespace internal {
 
 using compiler::Node;
 
-Node* IteratorBuiltinsAssembler::GetIteratorMethod(Node* context,
-                                                   Node* object) {
+TNode<Object> IteratorBuiltinsAssembler::GetIteratorMethod(Node* context,
+                                                           Node* object) {
   return GetProperty(context, object, factory()->iterator_symbol());
 }
 
@@ -194,5 +195,68 @@ void IteratorBuiltinsAssembler::IteratorCloseOnException(
   Unreachable();
 }
 
+TNode<JSArray> IteratorBuiltinsAssembler::IterableToList(
+    TNode<Context> context, TNode<Object> iterable, TNode<Object> iterator_fn) {
+  Label fast_path(this), slow_path(this), done(this);
+
+  TVARIABLE(JSArray, created_list);
+
+  // This is a fast-path for ignoring the iterator.
+  // TODO(petermarshall): Port IterableToListCanBeElided to CSA.
+  Node* elided =
+      CallRuntime(Runtime::kIterableToListCanBeElided, context, iterable);
+  CSA_ASSERT(this, IsBoolean(elided));
+  Branch(IsTrue(elided), &fast_path, &slow_path);
+
+  BIND(&fast_path);
+  {
+    TNode<JSArray> input_array = CAST(iterable);
+    created_list = CAST(CloneFastJSArray(context, input_array));
+    Goto(&done);
+  }
+
+  BIND(&slow_path);
+  {
+    // 1. Let iteratorRecord be ? GetIterator(items, method).
+    IteratorRecord iterator_record =
+        GetIterator(context, iterable, iterator_fn);
+
+    // 2. Let values be a new empty List.
+    GrowableFixedArray values(state());
+
+    Variable* vars[] = {values.var_array(), values.var_length(),
+                        values.var_capacity()};
+    Label loop_start(this, 3, vars), loop_end(this);
+    Goto(&loop_start);
+    // 3. Let next be true.
+    // 4. Repeat, while next is not false
+    BIND(&loop_start);
+    {
+      //  a. Set next to ? IteratorStep(iteratorRecord).
+      TNode<Object> next =
+          CAST(IteratorStep(context, iterator_record, &loop_end));
+      //  b. If next is not false, then
+      //   i. Let nextValue be ? IteratorValue(next).
+      TNode<Object> next_value = CAST(IteratorValue(context, next));
+      //   ii. Append nextValue to the end of the List values.
+      values.Push(next_value);
+      Goto(&loop_start);
+    }
+    BIND(&loop_end);
+
+    created_list = values.ToJSArray(context);
+    Goto(&done);
+  }
+
+  BIND(&done);
+  return created_list.value();
+}
+
+TNode<JSArray> IteratorBuiltinsAssembler::IterableToList(
+    TNode<Context> context, TNode<Object> iterable) {
+  TNode<Object> method = GetIteratorMethod(context, iterable);
+  return IterableToList(context, iterable, method);
+}
+
 }  // namespace internal
 }  // namespace v8

src/builtins/builtins-iterator-gen.h

@@ -18,7 +18,7 @@ class IteratorBuiltinsAssembler : public CodeStubAssembler {
       : CodeStubAssembler(state) {}
 
   // Returns object[Symbol.iterator].
-  Node* GetIteratorMethod(Node* context, Node* object);
+  TNode<Object> GetIteratorMethod(Node* context, Node* object);
 
   // https://tc39.github.io/ecma262/#sec-getiterator --- never used for
   // @@asyncIterator.
@@ -53,6 +53,11 @@ class IteratorBuiltinsAssembler : public CodeStubAssembler {
                                 Label* if_exception, Variable* exception);
   void IteratorCloseOnException(Node* context, const IteratorRecord& iterator,
                                 Variable* exception);
+
+  // /#sec-iterabletolist
+  TNode<JSArray> IterableToList(TNode<Context> context, TNode<Object> iterable,
+                                TNode<Object> iterator_fn);
+  TNode<JSArray> IterableToList(TNode<Context> context, TNode<Object> iterable);
 };
 
 }  // namespace internal

src/builtins/builtins-typed-array-gen.cc

@@ -1647,44 +1647,6 @@ TF_BUILTIN(TypedArrayOf, TypedArrayBuiltinsAssembler) {
                  "%TypedArray%.of");
 }
 
-void TypedArrayBuiltinsAssembler::IterableToListSlowPath(
-    TNode<Context> context, TNode<Object> iterable, TNode<Object> iterator_fn,
-    Variable* created_list) {
-  IteratorBuiltinsAssembler iterator_assembler(state());
-
-  // 1. Let iteratorRecord be ? GetIterator(items, method).
-  IteratorRecord iterator_record =
-      iterator_assembler.GetIterator(context, iterable, iterator_fn);
-
-  // 2. Let values be a new empty List.
-  GrowableFixedArray values(state());
-
-  Variable* vars[] = {values.var_array(), values.var_length(),
-                      values.var_capacity()};
-  Label loop_start(this, 3, vars), loop_end(this);
-  Goto(&loop_start);
-  // 3. Let next be true.
-  // 4. Repeat, while next is not false
-  BIND(&loop_start);
-  {
-    //  a. Set next to ? IteratorStep(iteratorRecord).
-    TNode<Object> next = CAST(
-        iterator_assembler.IteratorStep(context, iterator_record, &loop_end));
-    //  b. If next is not false, then
-    //   i. Let nextValue be ? IteratorValue(next).
-    TNode<Object> next_value =
-        CAST(iterator_assembler.IteratorValue(context, next));
-    //   ii. Append nextValue to the end of the List values.
-    values.Push(next_value);
-    Goto(&loop_start);
-  }
-  BIND(&loop_end);
-
-  // 5. Return values.
-  TNode<JSArray> js_array_values = values.ToJSArray(context);
-  created_list->Bind(js_array_values);
-}
-
 // This builtin always returns a new JSArray and is thus safe to use even in the
 // presence of code that may call back into user-JS.
 TF_BUILTIN(IterableToList, TypedArrayBuiltinsAssembler) {
@@ -1692,33 +1654,8 @@ TF_BUILTIN(IterableToList, TypedArrayBuiltinsAssembler) {
   TNode<Object> iterable = CAST(Parameter(Descriptor::kIterable));
   TNode<Object> iterator_fn = CAST(Parameter(Descriptor::kIteratorFn));
 
-  Label fast_path(this), slow_path(this), done(this);
-
-  TVARIABLE(JSArray, created_list);
-
-  // This is a fast-path for ignoring the iterator.
-  // TODO(petermarshall): Port IterableToListCanBeElided to CSA.
-  Node* elided =
-      CallRuntime(Runtime::kIterableToListCanBeElided, context, iterable);
-  CSA_ASSERT(this, IsBoolean(elided));
-  Branch(IsTrue(elided), &fast_path, &slow_path);
-
-  BIND(&fast_path);
-  {
-    TNode<JSArray> input_array = CAST(iterable);
-    TNode<JSArray> new_array = CAST(CloneFastJSArray(context, input_array));
-    created_list = new_array;
-    Goto(&done);
-  }
-
-  BIND(&slow_path);
-  {
-    IterableToListSlowPath(context, iterable, iterator_fn, &created_list);
-    Goto(&done);
-  }
-
-  BIND(&done);
-  Return(created_list.value());
+  IteratorBuiltinsAssembler iterator_assembler(state());
+  Return(iterator_assembler.IterableToList(context, iterable, iterator_fn));
 }
 
 // ES6 #sec-%typedarray%.from

src/builtins/builtins-typed-array-gen.h

@@ -55,10 +55,6 @@ class TypedArrayBuiltinsAssembler : public BaseBuiltinsFromDSLAssembler {
                     TNode<Map> map, TNode<Smi> length,
                     TNode<Number> byte_offset);
 
-  void IterableToListSlowPath(TNode<Context> context, TNode<Object> iterable,
-                              TNode<Object> iterator_fn,
-                              Variable* created_list);
-
   TNode<Map> LoadMapForType(TNode<JSTypedArray> array);
   TNode<UintPtrT> CalculateExternalPointer(TNode<UintPtrT> backing_store,
                                            TNode<Number> byte_offset);