Fix crashes when going to natives. Throw an exception instead.

runtime/lib/array.cc

Index: runtime/lib/array.cc
===================================================================
--- runtime/lib/array.cc	(revision 1815)
+++ runtime/lib/array.cc	(working copy)
@@ -16,17 +16,10 @@
 DEFINE_NATIVE_ENTRY(ObjectArray_allocate, 2) {
   const TypeArguments& type_arguments =
       TypeArguments::CheckedHandle(arguments->At(0));
-  const Instance& length_instance = Instance::CheckedHandle(arguments->At(1));
-  if (!length_instance.IsSmi()) {
-    GrowableArray<const Object*> args;
-    args.Add(&length_instance);
-    Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
-  }
-  Smi& length = Smi::Handle();
-  length ^= length_instance.raw();
   ASSERT(type_arguments.IsNull() ||
          (type_arguments.IsInstantiated() && (type_arguments.Length() == 1)));
-  if (length.IsNull() || (length.Value() < 0)) {
+  GET_NATIVE_ARGUMENT(Smi, length, arguments->At(1));
+  if (length.Value() < 0) {
     GrowableArray<const Object*> args;
     args.Add(&length);
     Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
@@ -39,19 +32,7 @@
 
 DEFINE_NATIVE_ENTRY(ObjectArray_getIndexed, 2) {
   const Array& array = Array::CheckedHandle(arguments->At(0));
-  const Instance& index_instance = Instance::CheckedHandle(arguments->At(1));
-  if (!index_instance.IsSmi()) {
-    GrowableArray<const Object*> args;
-    args.Add(&index_instance);
-    Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
-  }
-  Smi& index = Smi::Handle();
-  index ^= index_instance.raw();
-  if (array.IsNull() || index.IsNull()) {
-    // TODO(asiva): Need to handle error cases.
-    UNIMPLEMENTED();
-    return;
-  }
+  GET_NATIVE_ARGUMENT(Smi, index, arguments->At(1));
   if ((index.Value() < 0) || (index.Value() >= array.Length())) {
     GrowableArray<const Object*> arguments;
     arguments.Add(&index);
@@ -64,20 +45,8 @@
 
 DEFINE_NATIVE_ENTRY(ObjectArray_setIndexed, 3) {
   const Array& array = Array::CheckedHandle(arguments->At(0));
-  const Instance& index_instance = Instance::CheckedHandle(arguments->At(1));
-  if (!index_instance.IsSmi()) {
-    GrowableArray<const Object*> args;
-    args.Add(&index_instance);
-    Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
-  }
-  Smi& index = Smi::Handle();
-  index ^= index_instance.raw();
+  GET_NATIVE_ARGUMENT(Smi, index, arguments->At(1));
   const Instance& value = Instance::CheckedHandle(arguments->At(2));
-  if (array.IsNull() || index.IsNull()) {
-    // TODO(asiva): Need to handle error cases.
-    UNIMPLEMENTED();
-    return;
-  }
   if ((index.Value() < 0) || (index.Value() >= array.Length())) {
     GrowableArray<const Object*> arguments;
     arguments.Add(&index);
@@ -89,11 +58,6 @@
 
 DEFINE_NATIVE_ENTRY(ObjectArray_getLength, 1) {
   const Array& array = Array::CheckedHandle(arguments->At(0));
-  if (array.IsNull()) {
-    // TODO(asiva): Need to handle error cases.
-    UNIMPLEMENTED();
-    return;
-  }
   const Smi& length = Smi::Handle(Smi::New(array.Length()));
   arguments->SetReturn(length);
 }
@@ -102,15 +66,10 @@
 // ObjectArray src, int srcStart, int dstStart, int count.
 DEFINE_NATIVE_ENTRY(ObjectArray_copyFromObjectArray, 5) {
   const Array& dest = Array::CheckedHandle(arguments->At(0));
-  const Array& source = Array::CheckedHandle(arguments->At(1));
-  const Smi& src_start = Smi::CheckedHandle(arguments->At(2));
-  const Smi& dst_start = Smi::CheckedHandle(arguments->At(3));
-  const Smi& count = Smi::CheckedHandle(arguments->At(4));
-  if (dest.IsNull() || source.IsNull() || src_start.IsNull() ||
-      dst_start.IsNull() || count.IsNull()) {
-    GrowableArray<const Object*> args;
-    Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
-  }
+  GET_NATIVE_ARGUMENT(Array, source, arguments->At(1));
+  GET_NATIVE_ARGUMENT(Smi, src_start, arguments->At(2));
+  GET_NATIVE_ARGUMENT(Smi, dst_start, arguments->At(3));
+  GET_NATIVE_ARGUMENT(Smi, count, arguments->At(4));
   intptr_t icount = count.Value();
   if (icount < 0) {
     GrowableArray<const Object*> args;