Implement Table#length and Table#get

src/wasm/wasm-js.cc

Index: src/wasm/wasm-js.cc
diff --git a/src/wasm/wasm-js.cc b/src/wasm/wasm-js.cc
index 36f286f73cffcd58a940d74e7d06442ed8fe1f92..8c21ac5e45962a77f78f76ae6bcb5a33a6d03ec4 100644
--- a/src/wasm/wasm-js.cc
+++ b/src/wasm/wasm-js.cc
@@ -482,22 +482,117 @@ void WebAssemblyMemory(const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(Utils::ToLocal(memory_obj));
 }
+
 void WebAssemblyTableGetLength(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(rossberg)
+  v8::Isolate* isolate = args.GetIsolate();
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),

[ahaas, 2016/10/13 09:12:58]

you call Utils::OpenHandle(*args.This()) twice here. Would it be worth storing
the result in a variable?

[rossberg, 2016/10/13 12:02:07]

It's just an accessor, so should be fast enough.

+                  i::Handle<i::Symbol>(i_context->wasm_table_sym()),
+                  "Receiver is not a WebAssembly.Table")) {
+    return;
+  }
+  i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  i::Handle<i::JSObject> receiver =
+      i::Handle<i::JSObject>::cast(Utils::OpenHandle(*args.This()));
+  i::Handle<i::Object> array(receiver->GetInternalField(0), i_isolate);

[ahaas, 2016/10/13 09:12:59]

Can you use a constant here instead of '0'?

[rossberg, 2016/10/13 12:02:07]

Done (also for some other field indices).

+  int length = i::Handle<i::FixedArray>::cast(array)->length();
+  v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
+  return_value.Set(v8::Number::New(isolate, length));
 }
+
 void WebAssemblyTableGrow(const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(rossberg)
+  v8::Isolate* isolate = args.GetIsolate();
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),
+                  i::Handle<i::Symbol>(i_context->wasm_table_sym()),
+                  "Receiver is not a WebAssembly.Table")) {
+    return;
+  }
+  // TODO(rossberg): grow table and update relevant instances.
+  v8::Local<v8::Value> e =
+      v8::Exception::TypeError(v8_str(isolate, "Table#grow unimplemented"));
+  isolate->ThrowException(e);
 }
+
 void WebAssemblyTableGet(const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(rossberg)
+  v8::Isolate* isolate = args.GetIsolate();
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),
+                  i::Handle<i::Symbol>(i_context->wasm_table_sym()),
+                  "Receiver is not a WebAssembly.Table")) {
+    return;
+  }
+  if (args.Length() < 1) {

[ahaas, 2016/10/13 09:12:58]

Does the spec actually say that a TypeError should be thrown if args.Length() <
1?

[rossberg, 2016/10/13 12:02:07]

Changed.

+    v8::Local<v8::Value> e = v8::Exception::TypeError(
+        v8_str(isolate, "Argument 0 must be an index"));
+    isolate->ThrowException(e);
+    return;
+  }
+
+  i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  i::Handle<i::JSObject> receiver =
+      i::Handle<i::JSObject>::cast(Utils::OpenHandle(*args.This()));
+  i::Handle<i::Object> array(receiver->GetInternalField(0), i_isolate);

[ahaas, 2016/10/13 09:12:58]

same here

[rossberg, 2016/10/13 12:02:07]

Done.

+  int i;
+  if (!args[0]->Int32Value(context).To(&i)) return;
+  v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
+  if (i >= 0 && i < i::Handle<i::FixedArray>::cast(array)->length()) {
+    i::Handle<i::Object> value(
+        i::Handle<i::FixedArray>::cast(array)->get(i), i_isolate);
+    return_value.Set(Utils::ToLocal(value));
+  }
 }
+
 void WebAssemblyTableSet(const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(rossberg)
+  v8::Isolate* isolate = args.GetIsolate();
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),
+                  i::Handle<i::Symbol>(i_context->wasm_table_sym()),
+                  "Receiver is not a WebAssembly.Table")) {
+    return;
+  }
+  if (args.Length() < 1) {

[ahaas, 2016/10/13 09:12:59]

This if is not needed, the next if also takes care of it.

[rossberg, 2016/10/13 12:02:07]

Obsolete.

+    v8::Local<v8::Value> e = v8::Exception::TypeError(
+        v8_str(isolate, "Argument 0 must be an index"));
+    isolate->ThrowException(e);
+    return;
+  }
+  if (args.Length() < 2 ||
+      !(args[1]->IsNull() ||
+        (args[1]->IsObject() && v8::Object::Cast(*args[1])->IsCallable()))) {
+    v8::Local<v8::Value> e = v8::Exception::TypeError(
+        v8_str(isolate, "Argument 1 must be a null or a function"));
+    isolate->ThrowException(e);
+    return;
+  }
+
+  // TODO(rossberg): set table element and update relevent instances.
+  v8::Local<v8::Value> e =
+      v8::Exception::TypeError(v8_str(isolate, "Table#set unimplemented"));
+  isolate->ThrowException(e);
 }
+
 void WebAssemblyMemoryGrow(const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(rossberg)
+  v8::Isolate* isolate = args.GetIsolate();
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),
+                  i::Handle<i::Symbol>(i_context->wasm_memory_sym()),
+                  "Receiver is not a WebAssembly.Memory")) {
+    return;
+  }
+
+  // TODO(rossberg): grow memory.
+  v8::Local<v8::Value> e =
+      v8::Exception::TypeError(v8_str(isolate, "Memory#grow unimplemented"));
+  isolate->ThrowException(e);
 }
+
 void WebAssemblyMemoryGetBuffer(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::Isolate* isolate = args.GetIsolate();