Optimize AOT's switchable calls for the monomorphic case.

runtime/vm/assembler_mips.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_ASSEMBLER_MIPS_H_
 #define VM_ASSEMBLER_MIPS_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_mips.h directly; use assembler.h instead.
 #endif
@@ skipping 225 matching lines @@
 
 class Assembler : public ValueObject {
  public:
   explicit Assembler(bool use_far_branches = false)
       : buffer_(),
         prologue_offset_(-1),
         use_far_branches_(use_far_branches),
         delay_slot_available_(false),
         in_delay_slot_(false),
         comments_(),
-        constant_pool_allowed_(true) { }
+        constant_pool_allowed_(true) {
+    MonomorphicCheckedEntry();
+  }
   ~Assembler() { }
 
   void PopRegister(Register r) { Pop(r); }
 
   void Bind(Label* label);
   void Jump(Label* label) { b(label); }
 
   // Misc. functionality
   intptr_t CodeSize() const { return buffer_.Size(); }
   intptr_t prologue_offset() const { return prologue_offset_; }
@@ skipping 16 matching lines @@
 
   void FinalizeInstructions(const MemoryRegion& region) {
     buffer_.FinalizeInstructions(region);
   }
 
   bool use_far_branches() const {
     return FLAG_use_far_branches || use_far_branches_;
   }
 
   void set_use_far_branches(bool b) {
-    ASSERT(buffer_.Size() == 0);
     use_far_branches_ = b;
   }
 
   void EnterFrame();
   void LeaveFrameAndReturn();
 
   // Set up a stub frame so that the stack traversal code can easily identify
   // a stub frame.
   void EnterStubFrame(intptr_t frame_size = 0);
   void LeaveStubFrame();
   // A separate macro for when a Ret immediately follows, so that we can use
   // the branch delay slot.
   void LeaveStubFrameAndReturn(Register ra = RA);
 
+  void NoMonomorphicCheckedEntry();
+  void MonomorphicCheckedEntry();
+
   void UpdateAllocationStats(intptr_t cid,
                              Register temp_reg,
                              Heap::Space space);
 
   void UpdateAllocationStatsWithSize(intptr_t cid,
                                      Register size_reg,
                                      Register temp_reg,
                                      Heap::Space space);
 
 
@@ skipping 1446 matching lines @@
                                   Register value,
                                   Label* no_update);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_MIPS_H_