Remove saving/restoring of the context at function entry.

runtime/vm/debugger_arm64.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/code_patcher.h"
 #include "vm/cpu.h"
 #include "vm/debugger.h"
 #include "vm/instructions.h"
 #include "vm/stub_code.h"
 
 namespace dart {
 
-RawInstance* ActivationFrame::GetInstanceCallReceiver(
-                 intptr_t num_actual_args) {
-  ASSERT(num_actual_args > 0);  // At minimum we have a receiver on the stack.
-  // Stack pointer points to last argument that was pushed on the stack.
-  const uword receiver_addr = sp() + ((num_actual_args - 1) * kWordSize);
-  const uword receiver = *reinterpret_cast<uword*>(receiver_addr);
-  return reinterpret_cast<RawInstance*>(receiver);
-}
-
-
-RawObject* ActivationFrame::GetClosureObject(intptr_t num_actual_args) {
-  // At a minimum we have the closure object on the stack.
-  ASSERT(num_actual_args > 0);
-  // Stack pointer points to last argument that was pushed on the stack.
-  const uword closure_addr = sp() + ((num_actual_args - 1) * kWordSize);
-  const uword closure = *reinterpret_cast<uword*>(closure_addr);
-  return reinterpret_cast<RawObject*>(closure);
-}
-
-
 uword CodeBreakpoint::OrigStubAddress() const {
   const Code& code = Code::Handle(code_);
   const Array& object_pool = Array::Handle(code.ObjectPool());
   const uword offset = saved_value_;
   ASSERT((offset % kWordSize) == 0);
   const intptr_t index = (offset - Array::data_offset()) / kWordSize;
   const uword stub_address = reinterpret_cast<uword>(object_pool.At(index));
   ASSERT(stub_address % kWordSize == 0);
   return stub_address;
 }
@@ skipping 62 matching lines @@
       default:
         UNREACHABLE();
     }
   }
   is_enabled_ = false;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64