Expose SIMD.Float32x4 type to Javascript.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index f272aa501015889098573bf79142de6dd9a1e7c7..d38023c7af37afd63463e5a1a784b081e21f20c7 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -81,6 +81,8 @@ MaybeHandle<JSReceiver> Object::ToObject(Isolate* isolate,
     constructor = handle(native_context->string_function(), isolate);
   } else if (object->IsSymbol()) {
     constructor = handle(native_context->symbol_function(), isolate);
+  } else if (object->IsFloat32x4()) {
+    constructor = handle(native_context->float32x4_function(), isolate);
   } else {
     return MaybeHandle<JSReceiver>();
   }
@@ -610,7 +612,7 @@ Map* Object::GetRootMap(Isolate* isolate) {
 
   HeapObject* heap_object = HeapObject::cast(this);
 
-  // The object is either a number, a string, a boolean,
+  // The object is either a number, a string, a symbol, a boolean, a SIMD value,
   // a real JS object, or a Harmony proxy.
   if (heap_object->IsJSReceiver()) {
     return heap_object->map();
@@ -629,6 +631,9 @@ Map* Object::GetRootMap(Isolate* isolate) {
   if (heap_object->IsBoolean()) {
     return context->boolean_function()->initial_map();
   }
+  if (heap_object->IsFloat32x4()) {
+    return context->float32x4_function()->initial_map();
+  }
   return isolate->heap()->null_value()->map();
 }
 
@@ -1530,8 +1535,12 @@ void HeapNumber::HeapNumberPrint(std::ostream& os) {  // NOLINT
 
 
 void Float32x4::Float32x4Print(std::ostream& os) {  // NOLINT
-  os << get_lane(0) << ", " << get_lane(1) << ", " << get_lane(2) << ", "
-     << get_lane(3);
+  char arr[100];
+  Vector<char> buffer(arr, arraysize(arr));
+  os << std::string(DoubleToCString(get_lane(0), buffer)) << ", "
+     << std::string(DoubleToCString(get_lane(1), buffer)) << ", "
+     << std::string(DoubleToCString(get_lane(2), buffer)) << ", "
+     << std::string(DoubleToCString(get_lane(3), buffer));
 }