hphp/runtime/vm/jit/state-vector.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2014 Facebook, Inc. (http://www.facebook.com)     |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef incl_HPHP_JIT_STATE_VECTOR_H_
  18 #define incl_HPHP_JIT_STATE_VECTOR_H_
  19
  20 #include <type_traits>
  21
  22 #include "hphp/runtime/vm/jit/containers.h"
  23 #include "hphp/runtime/vm/jit/ir-unit.h"
  24
  25 namespace HPHP { namespace jit {
  26
  27 //////////////////////////////////////////////////////////////////////
  28
  29 /*
  30  * Utility to keep a vector of state about each key, indexed by
  31  * key->id(), where key can be an IRInstruction, Block, or SSATmp.
  32  *
  33  * Takes an `init' element, which everything is defaulted to.
  34  */
  35 template<class Key, class Info>
  36 struct StateVector {
  37   using InfoVector      = jit::vector<Info>;
  38   using iterator        = typename InfoVector::iterator;
  39   using const_iterator  = typename InfoVector::const_iterator;
  40   using reference       = typename InfoVector::reference;
  41   using const_reference = typename InfoVector::const_reference;
  42
  43   static_assert(
  44     std::is_same<Key,Block>::value ||
  45     std::is_same<Key,IRInstruction>::value ||
  46     std::is_same<Key,SSATmp>::value,
  47     "StateVector can only be used with Block, IRInstruction, or SSATmp"
  48   );
  49
  50   StateVector(const IRUnit& unit, Info init)
  51     : m_unit(&unit)
  52     , m_init(std::move(init))
  53     , m_info(unit.numIds(nullKey), m_init)
  54   {}
  55
  56   StateVector(const StateVector&) = default;
  57   StateVector(StateVector&&) = default;
  58   StateVector& operator=(const StateVector&) = delete;
  59   StateVector& operator=(StateVector&&) = default;
  60
  61   reference operator[](uint32_t id) {
  62     if (id >= m_info.size()) grow();
  63     return m_info[id];
  64   }
  65
  66   const_reference operator[](uint32_t id) const {
  67     assertx(id < m_unit->numIds(nullKey));
  68     return id < m_info.size() ? m_info[id] : m_init;
  69   }
  70
  71   reference operator[](const Key& k) { return (*this)[k.id()]; }
  72   reference operator[](const Key* k) { return (*this)[k->id()]; }
  73
  74   const_reference operator[](const Key& k) const { return (*this)[k.id()]; }
  75   const_reference operator[](const Key* k) const { return (*this)[k->id()]; }
  76
  77   iterator begin()              { return m_info.begin(); }
  78   iterator end()                { return m_info.end(); }
  79   const_iterator begin()  const { return m_info.begin(); }
  80   const_iterator end()    const { return m_info.end(); }
  81   const_iterator cbegin() const { return m_info.cbegin(); }
  82   const_iterator cend()   const { return m_info.cend(); }
  83
  84 private:
  85   void grow() {
  86     m_info.resize(m_unit->numIds(nullKey), m_init);
  87   }
  88
  89 private:
  90   static constexpr Key* nullKey { nullptr };
  91   const IRUnit* m_unit;
  92   Info m_init;
  93   InfoVector m_info;
  94 };
  95
  96 //////////////////////////////////////////////////////////////////////
  97
  98 }}
  99
 100 #endif