KeyedLoadIC should have same register spec as LoadIC.

src/arm64/code-stubs-arm64.cc

Index: src/arm64/code-stubs-arm64.cc
diff --git a/src/arm64/code-stubs-arm64.cc b/src/arm64/code-stubs-arm64.cc
index 427f82a73f1d44ca14d798bb8ec3cbe0ee53d5df..6dc564da4a9d434a7643b1a3102f5d1dd0cfb6cb 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -1727,26 +1727,15 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
 
 void FunctionPrototypeStub::Generate(MacroAssembler* masm) {
   Label miss;
-  Register receiver;
+  Register receiver = LoadIC::ReceiverRegister();
+  Register name = LoadIC::NameRegister();
+
+  ASSERT(kind() == Code::LOAD_IC ||
+         kind() == Code::KEYED_LOAD_IC);
+
   if (kind() == Code::KEYED_LOAD_IC) {
-    // ----------- S t a t e -------------
-    //  -- lr    : return address
-    //  -- x1    : receiver
-    //  -- x0    : key
-    // -----------------------------------
-    Register key = x0;
-    receiver = x1;
-    __ Cmp(key, Operand(isolate()->factory()->prototype_string()));
+    __ Cmp(name, Operand(isolate()->factory()->prototype_string()));
     __ B(ne, &miss);
-  } else {
-    ASSERT(kind() == Code::LOAD_IC);
-    // ----------- S t a t e -------------
-    //  -- lr    : return address
-    //  -- x2    : name
-    //  -- x0    : receiver
-    //  -- sp[0] : receiver
-    // -----------------------------------
-    receiver = x0;
   }
 
   StubCompiler::GenerateLoadFunctionPrototype(masm, receiver, x10, x11, &miss);