[V8][Wasm] Wasm throws.

src/runtime/runtime-wasm.cc

Index: src/runtime/runtime-wasm.cc
diff --git a/src/runtime/runtime-wasm.cc b/src/runtime/runtime-wasm.cc
index 02073b77a090cdf1bc382d7d2b1c32f2f297f8cb..6f10db23ad9fb2bcb4d5a28b1e5d509563658562 100644
--- a/src/runtime/runtime-wasm.cc
+++ b/src/runtime/runtime-wasm.cc
@@ -118,5 +118,18 @@ RUNTIME_FUNCTION(Runtime_WasmThrowTypeError) {
   THROW_NEW_ERROR_RETURN_FAILURE(
       isolate, NewTypeError(MessageTemplate::kWasmTrapTypeError));
 }
+
+RUNTIME_FUNCTION(Runtime_WasmThrow) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(2, args.length());
+  Object* upper = args[1];
+  Object* lower = args[0];

[Michael Starzinger, 2016/09/15 12:33:36]

nit: Please use CONVERT_SMI_ARG_CHECKED here.

[John, 2016/09/15 12:42:05]

Done.

+
+  const int32_t thrown_value =
+      (Smi::cast(upper)->value() << 16) | Smi::cast(lower)->value();
+
+  return isolate->Throw(*isolate->factory()->NewNumberFromInt(thrown_value));
+}
+
 }  // namespace internal
 }  // namespace v8