Introduce a class to carry around a deoptimization reason.

src/deoptimizer.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_DEOPTIMIZER_H_
 #define V8_DEOPTIMIZER_H_
 
 #include "src/v8.h"
 
 #include "src/allocation.h"
@@ skipping 83 matching lines @@
     EAGER,
     LAZY,
     SOFT,
     // This last bailout type is not really a bailout, but used by the
     // debugger to deoptimize stack frames to allow inspection.
     DEBUGGER
   };
 
   static const int kBailoutTypesWithCodeEntry = SOFT + 1;
 
+  struct Reason {
+    Reason(const char* m, const char* d) : mnemonic(m), detail(d) {}
+    const char* mnemonic;
+    const char* detail;
+  };
+
   struct JumpTableEntry : public ZoneObject {
-    inline JumpTableEntry(Address entry, const char* the_mnemonic,
-                          const char* the_reason, Deoptimizer::BailoutType type,
-                          bool frame)
+    inline JumpTableEntry(Address entry, const Reason& the_reason,
+                          Deoptimizer::BailoutType type, bool frame)
         : label(),
           address(entry),
-          mnemonic(the_mnemonic),
           reason(the_reason),
           bailout_type(type),
           needs_frame(frame) {}
     Label label;
     Address address;
-    const char* mnemonic;
-    const char* reason;
+    Reason reason;
     Deoptimizer::BailoutType bailout_type;
     bool needs_frame;
   };
 
   static bool TraceEnabledFor(BailoutType deopt_type,
                               StackFrame::Type frame_type);
   static const char* MessageFor(BailoutType type);
 
   int output_count() const { return output_count_; }
 
@@ skipping 832 matching lines @@
   Object** parameters_;
   Object** expression_stack_;
   int source_position_;
 
   friend class Deoptimizer;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_DEOPTIMIZER_H_