hphp/hhbbc/type-builtins.cpp

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present 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 #include "hphp/hhbbc/type-builtins.h"
  17
  18 #include "hphp/runtime/base/type-string.h"
  19 #include "hphp/runtime/vm/native.h"
  20 #include "hphp/hhbbc/representation.h"
  21
  22 namespace HPHP::HHBBC {
  23
  24 //////////////////////////////////////////////////////////////////////
  25
  26 Type native_function_return_type(const php::Func* f) {
  27   assertx(f->isNative);
  28
  29   // Infer the type from the HNI declaration
  30   auto t = [&]{
  31     auto const hni = f->retTypeConstraint.asSystemlibType();
  32     return hni ? from_DataType(*hni) : TInitCell;
  33   }();
  34
  35   // Non-simple types (ones that are represented by pointers) can always
  36   // possibly be null.
  37   if (t.subtypeOf(BStr | BArrLike | BObj | BRes)) {
  38     t = opt(std::move(t));
  39   } else {
  40     // Otherwise it should be a simple type or possibly everything.
  41     assertx(t == TInitCell || t.subtypeOf(BBool | BInt | BDbl | BNull));
  42   }
  43
  44   t = remove_uninit(std::move(t));
  45   if (!f->hasInOutArgs) return t;
  46
  47   std::vector<Type> types;
  48   types.emplace_back(std::move(t));
  49
  50   for (auto const& p : f->params) {
  51     if (!p.inout) continue;
  52     auto const dt =
  53       Native::builtinOutType(p.typeConstraint, p.userAttributes);
  54     if (!dt) {
  55       types.emplace_back(TInitCell);
  56       continue;
  57     }
  58     auto t = from_DataType(*dt);
  59     if (p.typeConstraint.isNullable()) t = opt(std::move(t));
  60     types.emplace_back(remove_uninit(std::move(t)));
  61   }
  62   std::reverse(types.begin()+1, types.end());
  63
  64   return vec(std::move(types));
  65 }
  66
  67 }