Step next should respect do/while condition block.

src/x64/codegen-x64.h

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 538 matching lines @@
     DONT_KNOW
   };
   ConditionAnalysis AnalyzeCondition(Expression* cond);
 
   // Methods used to indicate which source code is generated for. Source
   // positions are collected by the assembler and emitted with the relocation
   // information.
   void CodeForFunctionPosition(FunctionLiteral* fun);
   void CodeForReturnPosition(FunctionLiteral* fun);
   void CodeForStatementPosition(Statement* node);
+  void CodeForDoWhileConditionPosition(DoWhileStatement* stmt);
   void CodeForSourcePosition(int pos);
 
 #ifdef DEBUG
   // True if the registers are valid for entry to a block.  There should
   // be no frame-external references to (non-reserved) registers.
   bool HasValidEntryRegisters();
 #endif
 
   bool is_eval_;  // Tells whether code is generated for eval.
   Handle<Script> script_;
@@ skipping 166 matching lines @@
   void SetArgsReversed() { args_reversed_ = true; }
   bool HasSmiCodeInStub() { return (flags_ & NO_SMI_CODE_IN_STUB) == 0; }
   bool HasArgumentsInRegisters() { return args_in_registers_; }
   bool HasArgumentsReversed() { return args_reversed_; }
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_CODEGEN_X64_H_