hphp/php7/lvalue.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010- 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_PHP7_LVALUE_H
  18 #define incl_HPHP_PHP7_LVALUE_H
  19
  20 #include "hphp/runtime/vm/hhbc.h"
  21 #include "hphp/php7/zend/zend.h"
  22 #include "hphp/php7/bytecode.h"
  23 #include "hphp/php7/cfg.h"
  24
  25 namespace HPHP { namespace php7 {
  26
  27 /* This is a value that we can take a base pointer to--different from Lvalue
  28  * since PHP has values that can be indexed but not assigned to: namely, array
  29  * expressions
  30  */
  31 struct BaseValue {
  32   virtual ~BaseValue() = default;
  33
  34   struct MinstrSeq;
  35   virtual CFG getB(MinstrSeq& seq) = 0;
  36 };
  37
  38 /* This is a PHP value that acts like an lvalue--that is, it can be both read
  39  * from or assigned to. Mostly this corresponds to locals, but other lvalues
  40  * are object properties or elements of an array
  41  */
  42 struct Lvalue : BaseValue {
  43   /* Get an lvalue for an expression--if the expression is not an lvalue,
  44    * returns nullptr; */
  45   static std::unique_ptr<Lvalue> getLvalue(const zend_ast* ast);
  46
  47   virtual CFG getC() = 0;
  48   virtual CFG getV() = 0;
  49   virtual CFG getF(uint32_t slot) = 0;
  50   virtual CFG assign(const zend_ast* rhs) = 0;
  51   virtual CFG bind(const zend_ast* rhs) = 0;
  52   virtual CFG assignOp(SetOpOp op, const zend_ast* rhs) = 0;
  53   virtual CFG incDec(IncDecOp op) = 0;
  54 };
  55
  56 }} // HPHP::php7
  57
  58 #endif // incl_HPHP_PHP7_LVALUE_H