Mark instruction blocks with spills (for frame elision).

src/compiler/instruction.h

 // Copyright 2014 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.
 
 #ifndef V8_COMPILER_INSTRUCTION_H_
 #define V8_COMPILER_INSTRUCTION_H_
 
 #include <deque>
 #include <iosfwd>
 #include <map>
@@ skipping 1034 matching lines @@
 
   int LastLoopInstructionIndex(const InstructionBlock* block) {
     return instruction_blocks_->at(block->loop_end().ToSize() - 1)
         ->last_instruction_index();
   }
 
   const InstructionBlock* InstructionBlockAt(RpoNumber rpo_number) const {
     return instruction_blocks_->at(rpo_number.ToSize());
   }
 
-  const InstructionBlock* GetInstructionBlock(int instruction_index) const;
+  InstructionBlock* GetInstructionBlock(int instruction_index) const;
 
   static MachineType DefaultRepresentation() {
     return kPointerSize == 8 ? kRepWord64 : kRepWord32;
   }
   MachineType GetRepresentation(int virtual_register) const;
   void MarkAsRepresentation(MachineType machine_type, int virtual_register);
 
   bool IsReference(int virtual_register) const {
     return GetRepresentation(virtual_register) == kRepTagged;
   }
@@ skipping 122 matching lines @@
 
 
 std::ostream& operator<<(std::ostream& os,
                          const PrintableInstructionSequence& code);
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_H_