Emit comment with instruction+reason before deopt calls.

src/x87/lithium-codegen-x87.h

 // 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.
 
 #ifndef V8_X87_LITHIUM_CODEGEN_X87_H_
 #define V8_X87_LITHIUM_CODEGEN_X87_H_
 
 #include "src/x87/lithium-x87.h"
 
 #include "src/base/logging.h"
@@ skipping 216 matching lines @@
                          int formal_parameter_count,
                          int arity,
                          LInstruction* instr,
                          EDIState edi_state);
 
   void RecordSafepointWithLazyDeopt(LInstruction* instr,
                                     SafepointMode safepoint_mode);
 
   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
                                             Safepoint::DeoptMode mode);
+  void DeoptimizeIf(Condition cc, LInstruction* instr, const char* reason,
+                    Deoptimizer::BailoutType bailout_type);
   void DeoptimizeIf(Condition cc, LInstruction* instr,
-                    Deoptimizer::BailoutType bailout_type);
-  void DeoptimizeIf(Condition cc, LInstruction* instr);
+                    const char* reason = NULL);
 
   bool DeoptEveryNTimes() {
     return FLAG_deopt_every_n_times != 0 && !info()->IsStub();
   }
 
   void AddToTranslation(LEnvironment* environment,
                         Translation* translation,
                         LOperand* op,
                         bool is_tagged,
                         bool is_uint32,
@@ skipping 242 matching lines @@
   Label exit_;
   Label* external_exit_;
   Label done_;
   int instruction_index_;
   LCodeGen::X87Stack x87_stack_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X87_LITHIUM_CODEGEN_X87_H_