diff --git a/src/ia32/ic-ia32.cc b/src/ia32/ic-ia32.cc
index f7d07972f4..d9dcb7c912 100644
--- a/src/ia32/ic-ia32.cc
+++ b/src/ia32/ic-ia32.cc
@@ -749,12 +749,10 @@ void LoadIC::Generate(MacroAssembler* masm, const ExternalReference& f) {
   // -----------------------------------
 
   __ mov(eax, Operand(esp, kPointerSize));
-
-  // Move the return address below the arguments.
   __ pop(ebx);
-  __ push(eax);
-  __ push(ecx);
-  __ push(ebx);
+  __ push(eax);  // receiver
+  __ push(ecx);  // name
+  __ push(ebx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(f, 2);
@@ -877,12 +875,10 @@ void KeyedLoadIC::Generate(MacroAssembler* masm, const ExternalReference& f) {
 
   __ mov(eax, Operand(esp, kPointerSize));
   __ mov(ecx, Operand(esp, 2 * kPointerSize));
-
-  // Move the return address below the arguments.
   __ pop(ebx);
-  __ push(ecx);
-  __ push(eax);
-  __ push(ebx);
+  __ push(ecx);  // receiver
+  __ push(eax);  // name
+  __ push(ebx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(f, 2);
@@ -917,12 +913,12 @@ void StoreIC::GenerateExtendStorage(MacroAssembler* masm) {
   //  -- esp[4] : receiver
   // -----------------------------------
 
-  // Move the return address below the arguments.
   __ pop(ebx);
-  __ push(Operand(esp, 0));
-  __ push(ecx);
-  __ push(eax);
-  __ push(ebx);
+  __ push(Operand(esp, 0));  // receiver
+  __ push(ecx);  // transition map
+  __ push(eax);  // value
+  __ push(ebx);  // return address
+
   // Perform tail call to the entry.
   __ TailCallRuntime(
       ExternalReference(IC_Utility(kSharedStoreIC_ExtendStorage)), 3);
diff --git a/src/ic.cc b/src/ic.cc
index 090d7a3bb3..1d2a798104 100644
--- a/src/ic.cc
+++ b/src/ic.cc
@@ -978,10 +978,6 @@ Object* StoreIC::Store(State state,
     return *value;
   }
 
-  // TODO(X64): Enable inline cache for StoreIC.
-#ifdef V8_TARGET_ARCH_X64
-  USE(&LookupForWrite);  // The compiler complains otherwise.
-#else
   // Lookup the property locally in the receiver.
   if (FLAG_use_ic && !receiver->IsJSGlobalProxy()) {
     LookupResult lookup;
@@ -989,7 +985,6 @@ Object* StoreIC::Store(State state,
       UpdateCaches(&lookup, state, receiver, name, value);
     }
   }
-#endif
 
   // Set the property.
   return receiver->SetProperty(*name, *value, NONE);
diff --git a/src/x64/ic-x64.cc b/src/x64/ic-x64.cc
index 247e9e6915..ed299e9e52 100644
--- a/src/x64/ic-x64.cc
+++ b/src/x64/ic-x64.cc
@@ -183,12 +183,10 @@ void KeyedLoadIC::Generate(MacroAssembler* masm,
 
   __ movq(rax, Operand(rsp, kPointerSize));
   __ movq(rcx, Operand(rsp, 2 * kPointerSize));
-
-  // Move the return address below the arguments.
   __ pop(rbx);
-  __ push(rcx);
-  __ push(rax);
-  __ push(rbx);
+  __ push(rcx);  // receiver
+  __ push(rax);  // name
+  __ push(rbx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(f, 2);
@@ -369,19 +367,19 @@ void KeyedStoreIC::Generate(MacroAssembler* masm, ExternalReference const& f) {
   //  -- rsp[16] : receiver
   // -----------------------------------
 
-  // Move the return address below the arguments.
   __ pop(rcx);
-  __ push(Operand(rsp, 1 * kPointerSize));
-  __ push(Operand(rsp, 1 * kPointerSize));
-  __ push(rax);
-  __ push(rcx);
+  __ push(Operand(rsp, 1 * kPointerSize));  // receiver
+  __ push(Operand(rsp, 1 * kPointerSize));  // key
+  __ push(rax);  // value
+  __ push(rcx);  // return address
 
   // Do tail-call to runtime routine.
   __ TailCallRuntime(f, 3);
 }
 
 void KeyedStoreIC::GenerateExtendStorage(MacroAssembler* masm) {
-  Generate(masm, ExternalReference(IC_Utility(kKeyedStoreIC_Miss)));
+  __ int3();
+  __ movq(rax, Immediate(0xdead1234));
 }
 
 
@@ -584,11 +582,10 @@ void LoadIC::Generate(MacroAssembler* masm, ExternalReference const& f) {
 
   __ movq(rax, Operand(rsp, kPointerSize));
 
-  // Move the return address below the arguments.
   __ pop(rbx);
-  __ push(rax);
-  __ push(rcx);
-  __ push(rbx);
+  __ push(rax);  // receiver
+  __ push(rcx);  // name
+  __ push(rbx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(f, 2);
@@ -654,19 +651,33 @@ void StoreIC::Generate(MacroAssembler* masm, ExternalReference const& f) {
   //  -- rsp[0] : return address
   //  -- rsp[8] : receiver
   // -----------------------------------
-  // Move the return address below the arguments.
   __ pop(rbx);
-  __ push(Operand(rsp, 0));
-  __ push(rcx);
-  __ push(rax);
-  __ push(rbx);
+  __ push(Operand(rsp, 0));  // receiver
+  __ push(rcx);  // name
+  __ push(rax);  // value
+  __ push(rbx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(f, 3);
 }
 
 void StoreIC::GenerateExtendStorage(MacroAssembler* masm) {
-  Generate(masm, ExternalReference(IC_Utility(kStoreIC_Miss)));
+  // ----------- S t a t e -------------
+  //  -- rax    : value
+  //  -- rcx    : Map (target of map transition)
+  //  -- rsp[0] : return address
+  //  -- rsp[8] : receiver
+  // -----------------------------------
+
+  __ pop(rbx);
+  __ push(Operand(rsp, 0));  // receiver
+  __ push(rcx);  // transition map
+  __ push(rax);  // value
+  __ push(rbx);  // return address
+
+  // Perform tail call to the entry.
+  __ TailCallRuntime(
+      ExternalReference(IC_Utility(kSharedStoreIC_ExtendStorage)), 3);
 }
 
 void StoreIC::GenerateMegamorphic(MacroAssembler* masm) {
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 457011be88..26c8c9bb0c 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -151,6 +151,13 @@ void MacroAssembler::CallRuntime(Runtime::Function* f, int num_arguments) {
 
 void MacroAssembler::TailCallRuntime(ExternalReference const& ext,
                                      int num_arguments) {
+  // ----------- S t a t e -------------
+  //  -- rsp[0] : return address
+  //  -- rsp[8] : argument num_arguments - 1
+  //  ...
+  //  -- rsp[8 * num_arguments] : argument 0 (receiver)
+  // -----------------------------------
+
   // TODO(1236192): Most runtime routines don't need the number of
   // arguments passed in because it is constant. At some point we
   // should remove this need and make the runtime routine entry code
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index ba1399654f..32cbb98719 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -422,8 +422,8 @@ Object* LoadStubCompiler::CompileLoadGlobal(JSObject* object,
 Object* StoreStubCompiler::CompileStoreCallback(JSObject* a,
                                                 AccessorInfo* b,
                                                 String* c) {
-  UNIMPLEMENTED();
-  return NULL;
+  // TODO(X64): Implement a real stub.
+  return Failure::InternalError();
 }
 
 
@@ -463,16 +463,16 @@ Object* StoreStubCompiler::CompileStoreField(JSObject* object,
 
 
 Object* StoreStubCompiler::CompileStoreInterceptor(JSObject* a, String* b) {
-  UNIMPLEMENTED();
-  return NULL;
+  // TODO(X64): Implement a real stub.
+  return Failure::InternalError();
 }
 
 
 Object* StoreStubCompiler::CompileStoreGlobal(GlobalObject* object,
                                               JSGlobalPropertyCell* cell,
                                               String* name) {
-  UNIMPLEMENTED();
-  return NULL;
+  // TODO(X64): Implement a real stub.
+  return Failure::InternalError();
 }