mfbt/StaticAnalysisFunctions.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_StaticAnalysisFunctions_h
   8 #define mozilla_StaticAnalysisFunctions_h
   9
  10 #ifndef __cplusplus
  11 #  ifndef bool
  12 #    include <stdbool.h>
  13 #  endif
  14 #  define MOZ_CONSTEXPR
  15 #else  // __cplusplus
  16 #  include "mozilla/Attributes.h"
  17 #  define MOZ_CONSTEXPR constexpr
  18 #endif
  19 /*
  20  * Functions that are used as markers in Gecko code for static analysis. Their
  21  * purpose is to have different AST nodes generated during compile time and to
  22  * match them based on different checkers implemented in build/clang-plugin
  23  */
  24
  25 #ifdef MOZ_CLANG_PLUGIN
  26
  27 #  ifdef __cplusplus
  28 /**
  29  * MOZ_KnownLive - used to opt an argument out of the CanRunScript checker so
  30  * that we don't check it if is a strong ref.
  31  *
  32  * Example:
  33  * canRunScript(MOZ_KnownLive(rawPointer));
  34  */
  35 template <typename T>
  36 static MOZ_ALWAYS_INLINE T* MOZ_KnownLive(T* ptr) {
  37   return ptr;
  38 }
  39
  40 /**
  41  * Ditto, but for references.
  42  */
  43 template <typename T>
  44 static MOZ_ALWAYS_INLINE T& MOZ_KnownLive(T& ref) {
  45   return ref;
  46 }
  47
  48 #  endif
  49
  50 /**
  51  * MOZ_AssertAssignmentTest - used in MOZ_ASSERT in order to test the possible
  52  * presence of assignment instead of logical comparisons.
  53  *
  54  * Example:
  55  * MOZ_ASSERT(retVal = true);
  56  */
  57 static MOZ_ALWAYS_INLINE MOZ_CONSTEXPR bool MOZ_AssertAssignmentTest(
  58     bool exprResult) {
  59   return exprResult;
  60 }
  61
  62 #  define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) MOZ_AssertAssignmentTest(!!(expr))
  63
  64 #else
  65
  66 #  define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) (!!(expr))
  67 #  define MOZ_KnownLive(expr) (expr)
  68
  69 #endif /* MOZ_CLANG_PLUGIN */
  70 #endif /* StaticAnalysisFunctions_h */