Optimize AOT's switchable calls for the monomorphic case.

runtime/vm/debugger_ia32.cc

 // Copyright (c) 2011, 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_IA32)
 
 #include "vm/debugger.h"
 
 #include "vm/code_patcher.h"
@@ skipping 12 matching lines @@
   return saved_value_;
 }
 
 
 void CodeBreakpoint::PatchCode() {
   ASSERT(!is_enabled_);
   const Code& code = Code::Handle(code_);
   const Instructions& instrs = Instructions::Handle(code.instructions());
   Code& stub_target = Code::Handle();
   {
-    WritableInstructionsScope writable(instrs.EntryPoint(), instrs.size());
+    WritableInstructionsScope writable(instrs.PayloadStart(), instrs.size());
     switch (breakpoint_kind_) {
       case RawPcDescriptors::kIcCall:
       case RawPcDescriptors::kUnoptStaticCall: {
         stub_target = StubCode::ICCallBreakpoint_entry()->code();
         break;
       }
       case RawPcDescriptors::kRuntimeCall: {
         saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
         stub_target = StubCode::RuntimeCallBreakpoint_entry()->code();
         break;
       }
       default:
         UNREACHABLE();
     }
     saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
     CodePatcher::PatchStaticCallAt(pc_, code, stub_target);
   }
   is_enabled_ = true;
 }
 
 
 void CodeBreakpoint::RestoreCode() {
   ASSERT(is_enabled_);
   const Code& code = Code::Handle(code_);
   const Instructions& instrs = Instructions::Handle(code.instructions());
   {
-    WritableInstructionsScope writable(instrs.EntryPoint(), instrs.size());
+    WritableInstructionsScope writable(instrs.PayloadStart(), instrs.size());
     switch (breakpoint_kind_) {
       case RawPcDescriptors::kIcCall:
       case RawPcDescriptors::kUnoptStaticCall:
       case RawPcDescriptors::kRuntimeCall: {
         CodePatcher::PatchStaticCallAt(pc_, code, Code::Handle(saved_value_));
         break;
       }
       default:
         UNREACHABLE();
     }
   }
   is_enabled_ = false;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32