Generate TypedArrayInitialize builtin in hydrogen.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 38eabdae06aa5d9968d1479e050e883ff7b707f2..35409539df3bd912baf4034421420f30dc93fc73 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -1255,6 +1255,26 @@ HValue* HBitwise::Canonicalize() {
 }
 
 
+Representation HAdd::RepresentationFromInputs() {
+  Representation left_rep = left()->representation();
+  if (left_rep.IsExternal()) {
+    return Representation::External();
+  }
+  return HArithmeticBinaryOperation::RepresentationFromInputs();
+}
+
+
+Representation HAdd::RequiredInputRepresentation(int index) {
+  if (index == 2) {
+    Representation left_rep = left()->representation();
+    if (left_rep.IsExternal()) {
+      return Representation::Integer32();
+    }
+  }
+  return HArithmeticBinaryOperation::RequiredInputRepresentation(index);
+}
+
+
 static bool IsIdentityOperation(HValue* arg1, HValue* arg2, int32_t identity) {
   return arg1->representation().IsSpecialization() &&
     arg2->EqualsInteger32Constant(identity);
@@ -3749,6 +3769,18 @@ DEFINE_NEW_H_SIMPLE_ARITHMETIC_INSTR(HSub, -)
 #undef DEFINE_NEW_H_SIMPLE_ARITHMETIC_INSTR
 
 
+HAdd* HAdd::NewExternalPointerOffset(Zone* zone,
+                                     HValue* context,
+                                     HValue* base_pointer,
+                                     HValue* offset) {
+  HAdd* result = new(zone) HAdd(context, base_pointer, offset);
+
+  result->set_observed_input_representation(1, Representation::External());
+  result->initialize_output_representation(Representation::External());
+  return result;
+}
+
+
 HInstruction* HStringAdd::New(Zone* zone,
                               HValue* context,
                               HValue* left,