Add support for keyed-call on arrays of fast elements

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index 2700dbbe9c505c4e42a667695fe5ea409646c9d9..b826d2a7340736db7572637357049021d603e4b7 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -573,6 +573,45 @@ Handle<Code> KeyedLoadFieldStub::GenerateCode(Isolate* isolate) {
 }
 
 
+template<>
+HValue* CodeStubGraphBuilder<KeyedArrayCallStub>::BuildCodeStub() {
+  info()->SetGlobalScope(new(zone()) Scope(NULL, GLOBAL_SCOPE, zone()));
+  Scope* scope = new(zone()) Scope(
+      info()->global_scope(), FUNCTION_SCOPE, zone());
+  info()->SetScope(scope);
+
+  int argc = casted_stub()->argc() + 1;
+  for (int i = 0; i < argc; i++) {
+    scope->DeclareParameter(isolate()->factory()->empty_string(), VAR);
+  }

[danno, 2013/10/02 08:49:11]

This is a total hack. I am not sure how to do it better, but my intuition is
that it more properly belongs in the the graph or compiler-specific pieces that
calculate the size of the parameter area. Maybe the graph builder needs a
virtual method to compute the parameter count that by default uses the existing
logic and is overridden in this case to look at argc.

[Toon Verwaest, 2013/10/02 16:28:16]

Done.

+
+  HValue* receiver = Add<HParameter>(1);
+
+  // Load the expected array map from the context.
+  HValue* native_context = BuildGetNativeContext();
+  HValue* index = Add<HConstant>(
+      static_cast<int32_t>(Context::JS_ARRAY_MAPS_INDEX));
+  HValue* map_array = Add<HLoadKeyed>(
+      native_context, index, static_cast<HValue*>(NULL), FAST_ELEMENTS);
+  HValue* kind_index = Add<HConstant>(casted_stub()->elements_kind());
+  HValue* map = Add<HLoadKeyed>(
+      map_array, kind_index, static_cast<HValue*>(NULL), FAST_ELEMENTS);

[danno, 2013/10/02 08:49:11]

Please find a way to share this code in some way with
HGraphBuilder::JSArrayBuilder::EmitMapCode. 

[Toon Verwaest, 2013/10/02 16:28:16]

Done.

+
+  HValue* checked_receiver = Add<HCheckMapValue>(receiver, map);
+
+  HValue* function = BuildUncheckedMonomorphicElementAccess(
+      checked_receiver, GetParameter(0),
+      NULL, true, casted_stub()->elements_kind(),
+      false, NEVER_RETURN_HOLE, STANDARD_STORE);
+  return Add<HCallFunction>(function, argc, true);
+}
+
+
+Handle<Code> KeyedArrayCallStub::GenerateCode(Isolate* isolate) {
+  return DoGenerateCode(isolate, this);
+}
+
+
 template <>
 HValue* CodeStubGraphBuilder<KeyedStoreFastElementStub>::BuildCodeStub() {
   BuildUncheckedMonomorphicElementAccess(