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 #  define MOZ_CONSTEXPR constexpr
  17 #endif
  18 /*
  19  * Functions that are used as markers in Gecko code for static analysis. Their
  20  * purpose is to have different AST nodes generated during compile time and to
  21  * match them based on different checkers implemented in build/clang-plugin
  22  */
  23
  24 #ifdef MOZ_CLANG_PLUGIN
  25
  26 #  ifdef __cplusplus
  27 /**
  28  * MOZ_KnownLive - used to opt an argument out of the CanRunScript checker so
  29  * that we don't check it if is a strong ref.
  30  *
  31  * Example:
  32  * canRunScript(MOZ_KnownLive(rawPointer));
  33  */
  34 template <typename T>
  35 static MOZ_ALWAYS_INLINE T* MOZ_KnownLive(T* ptr) {
  36   return ptr;
  37 }
  38
  39 /**
  40  * Ditto, but for references.
  41  */
  42 template <typename T>
  43 static MOZ_ALWAYS_INLINE T& MOZ_KnownLive(T& ref) {
  44   return ref;
  45 }
  46
  47 #  endif
  48
  49 /**
  50  * MOZ_AssertAssignmentTest - used in MOZ_ASSERT in order to test the possible
  51  * presence of assignment instead of logical comparisons.
  52  *
  53  * Example:
  54  * MOZ_ASSERT(retVal = true);
  55  */
  56 static MOZ_ALWAYS_INLINE MOZ_CONSTEXPR bool MOZ_AssertAssignmentTest(
  57     bool exprResult) {
  58   return exprResult;
  59 }
  60
  61 #  define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) MOZ_AssertAssignmentTest(!!(expr))
  62
  63 #else
  64
  65 #  define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) (!!(expr))
  66 #  define MOZ_KnownLive(expr) (expr)
  67
  68 #endif /* MOZ_CLANG_PLUGIN */
  69 #endif /* StaticAnalysisFunctions_h */