hphp/runtime/vm/jit/type-source.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_TYPE_SOURCE_H_
  18 #define incl_HPHP_JIT_TYPE_SOURCE_H_
  19
  20 #include "hphp/runtime/vm/jit/containers.h"
  21 #include "hphp/util/assertions.h"
  22
  23 #include <string>
  24
  25 namespace HPHP { namespace jit {
  26
  27 struct IRInstruction;
  28 struct SSATmp;
  29
  30 /*
  31  * The source of a local's type. Either the current value or a guard.
  32  *
  33  * Used for guard relaxation, as we're constraining a value, local, or stack
  34  * slot, and we need to know what guards that type came from.
  35  */
  36 struct TypeSource {
  37   enum class Kind : uint8_t {
  38     Value,
  39     Guard,
  40   };
  41
  42   static TypeSource makeValue(SSATmp* value) {
  43     assert(value);
  44     TypeSource src;
  45     src.value = value;
  46     src.kind = Kind::Value;
  47     return src;
  48   }
  49
  50   static TypeSource makeGuard(const IRInstruction* guard) {
  51     assert(guard);
  52     TypeSource src;
  53     src.guard = guard;
  54     src.kind = Kind::Guard;
  55     return src;
  56   }
  57
  58   bool isGuard() const { return kind == Kind::Guard; }
  59   bool isValue() const { return kind == Kind::Value; }
  60
  61   bool operator==(const TypeSource& rhs) const {
  62     return kind == rhs.kind && value == rhs.value;
  63   }
  64   bool operator!=(const TypeSource& rhs) const {
  65     return !operator==(rhs);
  66   }
  67   bool operator<(const TypeSource& rhs) const;
  68
  69   std::string toString() const;
  70
  71   // Members.
  72   union {
  73     SSATmp* value{nullptr};
  74     const IRInstruction* guard;
  75   };
  76
  77   Kind kind;
  78 };
  79
  80 typedef jit::flat_set<TypeSource> TypeSourceSet;
  81
  82 std::string show(const TypeSource&);
  83 std::string show(const TypeSourceSet&);
  84
  85 }}
  86
  87 #endif