[compiler] Drop the CompareNilIC.

src/arm64/interface-descriptors-arm64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/arm64/interface-descriptors-arm64.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/interface-descriptors.h"
 
@@ skipping 328 matching lines @@
 
 void CompareDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // x1: left operand
   // x0: right operand
   Register registers[] = {x1, x0};
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
 
-void CompareNilDescriptor::InitializePlatformSpecific(
-    CallInterfaceDescriptorData* data) {
-  // x0: value to compare
-  Register registers[] = {x0};
-  data->InitializePlatformSpecific(arraysize(registers), registers);
-}
-
-
 void ToBooleanDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // x0: value
   Register registers[] = {x0};
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
 
 void BinaryOpDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
@@ skipping 148 matching lines @@
       x1    // the runtime function to call
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64