Revert "Revert "Reland 21774: Generate KeyedLoadGeneric with Hydrogen""

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 1ae91c28f164cfc44afd32d8749f95da1d69f69d..f8a6506c89b4a1cf633d9fa33fbdcc6fbdccb7d5 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -119,6 +119,16 @@ void RegExpConstructResultStub::InitializeInterfaceDescriptor(
 }
 
 
+void KeyedLoadGenericElementStub::InitializeInterfaceDescriptor(
+    CodeStubInterfaceDescriptor* descriptor) {
+  static Register registers[] = { rdx, rax };
+  descriptor->register_param_count_ = 2;
+  descriptor->register_params_ = registers;
+  descriptor->deoptimization_handler_ =
+      Runtime::FunctionForId(Runtime::kKeyedGetProperty)->entry;
+}
+
+
 void LoadFieldStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   static Register registers[] = { rax };