text: /*
     +----------------------------------------------------------------------+
     | HipHop for PHP                                                       |
     +----------------------------------------------------------------------+
     | Copyright (c) 2010-2015 Facebook, Inc. (http://www.facebook.com)     |
     +----------------------------------------------------------------------+
     | This source file is subject to version 3.01 of the PHP license,      |
     | that is bundled with this package in the file LICENSE, and is        |
     | available through the world-wide-web at the following url:           |
     | http://www.php.net/license/3_01.txt                                  |
     | If you did not receive a copy of the PHP license and are unable to   |
     | obtain it through the world-wide-web, please send a note to          |
     | license@php.net so we can mail you a copy immediately.               |
     +----------------------------------------------------------------------+
  */
  #ifndef incl_HPHP_DCE_H_
  #define incl_HPHP_DCE_H_
  
  namespace HPHP { namespace jit {
  
  struct IRUnit;
  
  //////////////////////////////////////////////////////////////////////
  
  /*
   * Perform very minimal DCE required to preserve the IR invariant that there
   * are no unreachable blocks in the unit.  All other IR invariants must hold
   * before running this function.
   */
  void mandatoryDCE(IRUnit&);
  
  /*
   * Perform a full DCE pass, which implies the mandatoryDCE as well.
   *
   * All IR invariants must hold before running this pass, except the one
   * restored by mandatoryDCE, which we allow passes to violate and rely on a
   * fullDCE run to fix.
   */
  void fullDCE(IRUnit&);
  
  //////////////////////////////////////////////////////////////////////
  
  }}
  
  #endif
  