absl/base/dynamic_annotations.h - chromiumos/third_party/webrtc-apm - Git at Google

 /*
  *  Copyright 2017 The Abseil Authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 /* This file defines dynamic annotations for use with dynamic analysis
    tool such as valgrind, PIN, etc.

    Dynamic annotation is a source code annotation that affects
    the generated code (that is, the annotation is not a comment).
    Each such annotation is attached to a particular
    instruction and/or to a particular object (address) in the program.

    The annotations that should be used by users are macros in all upper-case
    (e.g., ABSL_ANNOTATE_THREAD_NAME).

    Actual implementation of these macros may differ depending on the
    dynamic analysis tool being used.

    This file supports the following configurations:
    - Dynamic Annotations enabled (with static thread-safety warnings disabled).
      In this case, macros expand to functions implemented by Thread Sanitizer,
      when building with TSan. When not provided an external implementation,
      dynamic_annotations.cc provides no-op implementations.

    - Static Clang thread-safety warnings enabled.
      When building with a Clang compiler that supports thread-safety warnings,
      a subset of annotations can be statically-checked at compile-time. We
      expand these macros to static-inline functions that can be analyzed for
      thread-safety, but afterwards elided when building the final binary.

    - All annotations are disabled.
      If neither Dynamic Annotations nor Clang thread-safety warnings are
      enabled, then all annotation-macros expand to empty. */

 #ifndef ABSL_BASE_DYNAMIC_ANNOTATIONS_H_
 #define ABSL_BASE_DYNAMIC_ANNOTATIONS_H_

 #ifndef ABSL_DYNAMIC_ANNOTATIONS_ENABLED
 # define ABSL_DYNAMIC_ANNOTATIONS_ENABLED 0
 #endif

 #if ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0

   /* -------------------------------------------------------------
      Annotations that suppress errors.  It is usually better to express the
      program's synchronization using the other annotations, but these can
      be used when all else fails. */

   /* Report that we may have a benign race at "pointer", with size
      "sizeof(*(pointer))". "pointer" must be a non-void* pointer.  Insert at the
      point where "pointer" has been allocated, preferably close to the point
      where the race happens.  See also ABSL_ANNOTATE_BENIGN_RACE_STATIC. */
   #define ABSL_ANNOTATE_BENIGN_RACE(pointer, description) \
     AbslAnnotateBenignRaceSized(__FILE__, __LINE__, pointer, \
                             sizeof(*(pointer)), description)

   /* Same as ABSL_ANNOTATE_BENIGN_RACE(address, description), but applies to
      the memory range [address, address+size). */
   #define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) \
     AbslAnnotateBenignRaceSized(__FILE__, __LINE__, address, size, description)

   /* Enable (enable!=0) or disable (enable==0) race detection for all threads.
      This annotation could be useful if you want to skip expensive race analysis
      during some period of program execution, e.g. during initialization. */
   #define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) \
     AbslAnnotateEnableRaceDetection(__FILE__, __LINE__, enable)

   /* -------------------------------------------------------------
      Annotations useful for debugging. */

   /* Report the current thread name to a race detector. */
   #define ABSL_ANNOTATE_THREAD_NAME(name) \
     AbslAnnotateThreadName(__FILE__, __LINE__, name)

   /* -------------------------------------------------------------
      Annotations useful when implementing locks.  They are not
      normally needed by modules that merely use locks.
      The "lock" argument is a pointer to the lock object. */

   /* Report that a lock has been created at address "lock". */
   #define ABSL_ANNOTATE_RWLOCK_CREATE(lock) \
     AbslAnnotateRWLockCreate(__FILE__, __LINE__, lock)

   /* Report that a linker initialized lock has been created at address "lock".
    */
 #ifdef THREAD_SANITIZER
   #define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
     AbslAnnotateRWLockCreateStatic(__FILE__, __LINE__, lock)
 #else
   #define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) ABSL_ANNOTATE_RWLOCK_CREATE(lock)
 #endif

   /* Report that the lock at address "lock" is about to be destroyed. */
   #define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) \
     AbslAnnotateRWLockDestroy(__FILE__, __LINE__, lock)

   /* Report that the lock at address "lock" has been acquired.
      is_w=1 for writer lock, is_w=0 for reader lock. */
   #define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) \
     AbslAnnotateRWLockAcquired(__FILE__, __LINE__, lock, is_w)

   /* Report that the lock at address "lock" is about to be released. */
   #define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) \
     AbslAnnotateRWLockReleased(__FILE__, __LINE__, lock, is_w)

 #else  /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0 */

   #define ABSL_ANNOTATE_RWLOCK_CREATE(lock) /* empty */
   #define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) /* empty */
   #define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) /* empty */
   #define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) /* empty */
   #define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) /* empty */
   #define ABSL_ANNOTATE_BENIGN_RACE(address, description) /* empty */
   #define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) /* empty */
   #define ABSL_ANNOTATE_THREAD_NAME(name) /* empty */
   #define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) /* empty */

 #endif  /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED */

 /* These annotations are also made available to LLVM's Memory Sanitizer */
 #if ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 1 || defined(MEMORY_SANITIZER)
   #define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
     AbslAnnotateMemoryIsInitialized(__FILE__, __LINE__, address, size)

   #define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
     AbslAnnotateMemoryIsUninitialized(__FILE__, __LINE__, address, size)
 #else
   #define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) /* empty */
   #define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) /* empty */
 #endif  /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED || MEMORY_SANITIZER */

 /* TODO(delesley) -- Replace __CLANG_SUPPORT_DYN_ANNOTATION__ with the
    appropriate feature ID. */
 #if defined(__clang__) && (!defined(SWIG)) \
     && defined(__CLANG_SUPPORT_DYN_ANNOTATION__)

   #if ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0
     #define ABSL_ANNOTALYSIS_ENABLED
   #endif

   /* When running in opt-mode, GCC will issue a warning, if these attributes are
      compiled. Only include them when compiling using Clang. */
   #define ABSL_ATTRIBUTE_IGNORE_READS_BEGIN \
       __attribute((exclusive_lock_function("*")))
   #define ABSL_ATTRIBUTE_IGNORE_READS_END \
       __attribute((unlock_function("*")))
 #else
   #define ABSL_ATTRIBUTE_IGNORE_READS_BEGIN  /* empty */
   #define ABSL_ATTRIBUTE_IGNORE_READS_END  /* empty */
 #endif  /* defined(__clang__) && ... */

 #if (ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0) || defined(ABSL_ANNOTALYSIS_ENABLED)
   #define ABSL_ANNOTATIONS_ENABLED
 #endif

 #if (ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0)

   /* Request the analysis tool to ignore all reads in the current thread
      until ABSL_ANNOTATE_IGNORE_READS_END is called.
      Useful to ignore intentional racey reads, while still checking
      other reads and all writes.
      See also ABSL_ANNOTATE_UNPROTECTED_READ. */
   #define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
     AbslAnnotateIgnoreReadsBegin(__FILE__, __LINE__)

   /* Stop ignoring reads. */
   #define ABSL_ANNOTATE_IGNORE_READS_END() \
     AbslAnnotateIgnoreReadsEnd(__FILE__, __LINE__)

   /* Similar to ABSL_ANNOTATE_IGNORE_READS_BEGIN, but ignore writes instead. */
   #define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
     AbslAnnotateIgnoreWritesBegin(__FILE__, __LINE__)

   /* Stop ignoring writes. */
   #define ABSL_ANNOTATE_IGNORE_WRITES_END() \
     AbslAnnotateIgnoreWritesEnd(__FILE__, __LINE__)

 /* Clang provides limited support for static thread-safety analysis
    through a feature called Annotalysis. We configure macro-definitions
    according to whether Annotalysis support is available. */
 #elif defined(ABSL_ANNOTALYSIS_ENABLED)

   #define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
     AbslStaticAnnotateIgnoreReadsBegin(__FILE__, __LINE__)

   #define ABSL_ANNOTATE_IGNORE_READS_END() \
     AbslStaticAnnotateIgnoreReadsEnd(__FILE__, __LINE__)

   #define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
     AbslStaticAnnotateIgnoreWritesBegin(__FILE__, __LINE__)

   #define ABSL_ANNOTATE_IGNORE_WRITES_END() \
     AbslStaticAnnotateIgnoreWritesEnd(__FILE__, __LINE__)

 #else
   #define ABSL_ANNOTATE_IGNORE_READS_BEGIN()  /* empty */
   #define ABSL_ANNOTATE_IGNORE_READS_END()  /* empty */
   #define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN()  /* empty */
   #define ABSL_ANNOTATE_IGNORE_WRITES_END()  /* empty */
 #endif

 /* Implement the ANNOTATE_IGNORE_READS_AND_WRITES_* annotations using the more
    primitive annotations defined above. */
 #if defined(ABSL_ANNOTATIONS_ENABLED)

   /* Start ignoring all memory accesses (both reads and writes). */
   #define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() \
     do {                                           \
       ABSL_ANNOTATE_IGNORE_READS_BEGIN();               \
       ABSL_ANNOTATE_IGNORE_WRITES_BEGIN();              \
     }while (0)

   /* Stop ignoring both reads and writes. */
   #define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END()   \
     do {                                           \
       ABSL_ANNOTATE_IGNORE_WRITES_END();                \
       ABSL_ANNOTATE_IGNORE_READS_END();                 \
     }while (0)

 #else
   #define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN()  /* empty */
   #define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END()  /* empty */
 #endif

 /* Use the macros above rather than using these functions directly. */
 #include <stddef.h>
 #ifdef __cplusplus
 extern "C" {
 #endif
 void AbslAnnotateRWLockCreate(const char *file, int line,
                           const volatile void *lock);
 void AbslAnnotateRWLockCreateStatic(const char *file, int line,
                           const volatile void *lock);
 void AbslAnnotateRWLockDestroy(const char *file, int line,
                            const volatile void *lock);
 void AbslAnnotateRWLockAcquired(const char *file, int line,
                             const volatile void *lock, long is_w);  /* NOLINT */
 void AbslAnnotateRWLockReleased(const char *file, int line,
                             const volatile void *lock, long is_w);  /* NOLINT */
 void AbslAnnotateBenignRace(const char *file, int line,
                         const volatile void *address,
                         const char *description);
 void AbslAnnotateBenignRaceSized(const char *file, int line,
                         const volatile void *address,
                         size_t size,
                         const char *description);
 void AbslAnnotateThreadName(const char *file, int line,
                         const char *name);
 void AbslAnnotateEnableRaceDetection(const char *file, int line, int enable);
 void AbslAnnotateMemoryIsInitialized(const char *file, int line,
                                  const volatile void *mem, size_t size);
 void AbslAnnotateMemoryIsUninitialized(const char *file, int line,
                                    const volatile void *mem, size_t size);

 /* Annotations expand to these functions, when Dynamic Annotations are enabled.
    These functions are either implemented as no-op calls, if no Sanitizer is
    attached, or provided with externally-linked implementations by a library
    like ThreadSanitizer. */
 void AbslAnnotateIgnoreReadsBegin(const char *file, int line)
     ABSL_ATTRIBUTE_IGNORE_READS_BEGIN;
 void AbslAnnotateIgnoreReadsEnd(const char *file, int line)
     ABSL_ATTRIBUTE_IGNORE_READS_END;
 void AbslAnnotateIgnoreWritesBegin(const char *file, int line);
 void AbslAnnotateIgnoreWritesEnd(const char *file, int line);

 #if defined(ABSL_ANNOTALYSIS_ENABLED)
 /* When Annotalysis is enabled without Dynamic Annotations, the use of
    static-inline functions allows the annotations to be read at compile-time,
    while still letting the compiler elide the functions from the final build.

    TODO(delesley) -- The exclusive lock here ignores writes as well, but
    allows IGNORE_READS_AND_WRITES to work properly. */
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-function"
 static inline void AbslStaticAnnotateIgnoreReadsBegin(const char *file, int line)
     ABSL_ATTRIBUTE_IGNORE_READS_BEGIN { (void)file; (void)line; }
 static inline void AbslStaticAnnotateIgnoreReadsEnd(const char *file, int line)
     ABSL_ATTRIBUTE_IGNORE_READS_END { (void)file; (void)line; }
 static inline void AbslStaticAnnotateIgnoreWritesBegin(
     const char *file, int line) { (void)file; (void)line; }
 static inline void AbslStaticAnnotateIgnoreWritesEnd(
     const char *file, int line) { (void)file; (void)line; }
 #pragma GCC diagnostic pop
 #endif

 /* Return non-zero value if running under valgrind.

   If "valgrind.h" is included into dynamic_annotations.cc,
   the regular valgrind mechanism will be used.
   See http://valgrind.org/docs/manual/manual-core-adv.html about
   RUNNING_ON_VALGRIND and other valgrind "client requests".
   The file "valgrind.h" may be obtained by doing
      svn co svn://svn.valgrind.org/valgrind/trunk/include

   If for some reason you can't use "valgrind.h" or want to fake valgrind,
   there are two ways to make this function return non-zero:
     - Use environment variable: export RUNNING_ON_VALGRIND=1
     - Make your tool intercept the function AbslRunningOnValgrind() and
       change its return value.
  */
 int AbslRunningOnValgrind(void);

 /* AbslValgrindSlowdown returns:
     * 1.0, if (AbslRunningOnValgrind() == 0)
     * 50.0, if (AbslRunningOnValgrind() != 0 && getenv("VALGRIND_SLOWDOWN") == NULL)
     * atof(getenv("VALGRIND_SLOWDOWN")) otherwise
    This function can be used to scale timeout values:
    EXAMPLE:
    for (;;) {
      DoExpensiveBackgroundTask();
      SleepForSeconds(5 * AbslValgrindSlowdown());
    }
  */
 double AbslValgrindSlowdown(void);

 #ifdef __cplusplus
 }
 #endif

 /* ABSL_ANNOTATE_UNPROTECTED_READ is the preferred way to annotate racey reads.

      Instead of doing
         ABSL_ANNOTATE_IGNORE_READS_BEGIN();
         ... = x;
         ABSL_ANNOTATE_IGNORE_READS_END();
      one can use
         ... = ABSL_ANNOTATE_UNPROTECTED_READ(x); */
 #if defined(__cplusplus) && defined(ABSL_ANNOTATIONS_ENABLED)
 template <typename T>
 inline T ABSL_ANNOTATE_UNPROTECTED_READ(const volatile T &x) { /* NOLINT */
   ABSL_ANNOTATE_IGNORE_READS_BEGIN();
   T res = x;
   ABSL_ANNOTATE_IGNORE_READS_END();
   return res;
   }
 #else
   #define ABSL_ANNOTATE_UNPROTECTED_READ(x) (x)
 #endif

 #if ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0 && defined(__cplusplus)
   /* Apply ABSL_ANNOTATE_BENIGN_RACE_SIZED to a static variable. */
   #define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description)        \
     namespace {                                                       \
       class static_var ## _annotator {                                \
        public:                                                        \
         static_var ## _annotator() {                                  \
           ABSL_ANNOTATE_BENIGN_RACE_SIZED(&static_var,                     \
                                       sizeof(static_var),             \
             # static_var ": " description);                           \
         }                                                             \
       };                                                              \
       static static_var ## _annotator the ## static_var ## _annotator;\
     }  // namespace
 #else /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0 */
   #define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description)  /* empty */
 #endif /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED */

 #ifdef ADDRESS_SANITIZER
 /* Describe the current state of a contiguous container such as e.g.
  * std::vector or std::string. For more details see
  * sanitizer/common_interface_defs.h, which is provided by the compiler. */
 #include <sanitizer/common_interface_defs.h>
 #define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid) \
   __sanitizer_annotate_contiguous_container(beg, end, old_mid, new_mid)
 #define ABSL_ADDRESS_SANITIZER_REDZONE(name)         \
   struct { char x[8] __attribute__ ((aligned (8))); } name
 #else
 #define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid)
 #define ABSL_ADDRESS_SANITIZER_REDZONE(name)
 #endif  // ADDRESS_SANITIZER

 /* Undefine the macros intended only in this file. */
 #undef ABSL_ANNOTALYSIS_ENABLED
 #undef ABSL_ANNOTATIONS_ENABLED
 #undef ABSL_ATTRIBUTE_IGNORE_READS_BEGIN
 #undef ABSL_ATTRIBUTE_IGNORE_READS_END

 #endif  /* ABSL_BASE_DYNAMIC_ANNOTATIONS_H_ */
	/*
	* Copyright 2017 The Abseil Authors.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* https://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	/* This file defines dynamic annotations for use with dynamic analysis
	tool such as valgrind, PIN, etc.

	Dynamic annotation is a source code annotation that affects
	the generated code (that is, the annotation is not a comment).
	Each such annotation is attached to a particular
	instruction and/or to a particular object (address) in the program.

	The annotations that should be used by users are macros in all upper-case
	(e.g., ABSL_ANNOTATE_THREAD_NAME).

	Actual implementation of these macros may differ depending on the
	dynamic analysis tool being used.

	This file supports the following configurations:
	- Dynamic Annotations enabled (with static thread-safety warnings disabled).
	In this case, macros expand to functions implemented by Thread Sanitizer,
	when building with TSan. When not provided an external implementation,
	dynamic_annotations.cc provides no-op implementations.

	- Static Clang thread-safety warnings enabled.
	When building with a Clang compiler that supports thread-safety warnings,
	a subset of annotations can be statically-checked at compile-time. We
	expand these macros to static-inline functions that can be analyzed for
	thread-safety, but afterwards elided when building the final binary.

	- All annotations are disabled.
	If neither Dynamic Annotations nor Clang thread-safety warnings are
	enabled, then all annotation-macros expand to empty. */

	#ifndef ABSL_BASE_DYNAMIC_ANNOTATIONS_H_
	#define ABSL_BASE_DYNAMIC_ANNOTATIONS_H_

	#ifndef ABSL_DYNAMIC_ANNOTATIONS_ENABLED
	# define ABSL_DYNAMIC_ANNOTATIONS_ENABLED 0
	#endif

	#if ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0

	/* -------------------------------------------------------------
	Annotations that suppress errors. It is usually better to express the
	program's synchronization using the other annotations, but these can
	be used when all else fails. */

	/* Report that we may have a benign race at "pointer", with size
	"sizeof((pointer))". "pointer" must be a non-void pointer. Insert at the
	point where "pointer" has been allocated, preferably close to the point
	where the race happens. See also ABSL_ANNOTATE_BENIGN_RACE_STATIC. */
	#define ABSL_ANNOTATE_BENIGN_RACE(pointer, description) \
	AbslAnnotateBenignRaceSized(__FILE__, __LINE__, pointer, \
	sizeof(*(pointer)), description)

	/* Same as ABSL_ANNOTATE_BENIGN_RACE(address, description), but applies to
	the memory range [address, address+size). */
	#define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) \
	AbslAnnotateBenignRaceSized(__FILE__, __LINE__, address, size, description)

	/* Enable (enable!=0) or disable (enable==0) race detection for all threads.
	This annotation could be useful if you want to skip expensive race analysis
	during some period of program execution, e.g. during initialization. */
	#define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) \
	AbslAnnotateEnableRaceDetection(__FILE__, __LINE__, enable)

	/* -------------------------------------------------------------
	Annotations useful for debugging. */

	/* Report the current thread name to a race detector. */
	#define ABSL_ANNOTATE_THREAD_NAME(name) \
	AbslAnnotateThreadName(__FILE__, __LINE__, name)

	/* -------------------------------------------------------------
	Annotations useful when implementing locks. They are not
	normally needed by modules that merely use locks.
	The "lock" argument is a pointer to the lock object. */

	/* Report that a lock has been created at address "lock". */
	#define ABSL_ANNOTATE_RWLOCK_CREATE(lock) \
	AbslAnnotateRWLockCreate(__FILE__, __LINE__, lock)

	/* Report that a linker initialized lock has been created at address "lock".
	*/
	#ifdef THREAD_SANITIZER
	#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
	AbslAnnotateRWLockCreateStatic(__FILE__, __LINE__, lock)
	#else
	#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) ABSL_ANNOTATE_RWLOCK_CREATE(lock)
	#endif

	/* Report that the lock at address "lock" is about to be destroyed. */
	#define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) \
	AbslAnnotateRWLockDestroy(__FILE__, __LINE__, lock)

	/* Report that the lock at address "lock" has been acquired.
	is_w=1 for writer lock, is_w=0 for reader lock. */
	#define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) \
	AbslAnnotateRWLockAcquired(__FILE__, __LINE__, lock, is_w)

	/* Report that the lock at address "lock" is about to be released. */
	#define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) \
	AbslAnnotateRWLockReleased(__FILE__, __LINE__, lock, is_w)

	#else /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0 */

	#define ABSL_ANNOTATE_RWLOCK_CREATE(lock) /* empty */
	#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) /* empty */
	#define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) /* empty */
	#define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) /* empty */
	#define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) /* empty */
	#define ABSL_ANNOTATE_BENIGN_RACE(address, description) /* empty */
	#define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) /* empty */
	#define ABSL_ANNOTATE_THREAD_NAME(name) /* empty */
	#define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) /* empty */

	#endif /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED */

	/* These annotations are also made available to LLVM's Memory Sanitizer */
	#if ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 1 \|\| defined(MEMORY_SANITIZER)
	#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
	AbslAnnotateMemoryIsInitialized(__FILE__, __LINE__, address, size)

	#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
	AbslAnnotateMemoryIsUninitialized(__FILE__, __LINE__, address, size)
	#else
	#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) /* empty */
	#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) /* empty */
	#endif /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED \|\| MEMORY_SANITIZER */

	/* TODO(delesley) -- Replace __CLANG_SUPPORT_DYN_ANNOTATION__ with the
	appropriate feature ID. */
	#if defined(__clang__) && (!defined(SWIG)) \
	&& defined(__CLANG_SUPPORT_DYN_ANNOTATION__)

	#if ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0
	#define ABSL_ANNOTALYSIS_ENABLED
	#endif

	/* When running in opt-mode, GCC will issue a warning, if these attributes are
	compiled. Only include them when compiling using Clang. */
	#define ABSL_ATTRIBUTE_IGNORE_READS_BEGIN \
	__attribute((exclusive_lock_function("*")))
	#define ABSL_ATTRIBUTE_IGNORE_READS_END \
	__attribute((unlock_function("*")))
	#else
	#define ABSL_ATTRIBUTE_IGNORE_READS_BEGIN /* empty */
	#define ABSL_ATTRIBUTE_IGNORE_READS_END /* empty */
	#endif /* defined(__clang__) && ... */

	#if (ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0) \|\| defined(ABSL_ANNOTALYSIS_ENABLED)
	#define ABSL_ANNOTATIONS_ENABLED
	#endif

	#if (ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0)

	/* Request the analysis tool to ignore all reads in the current thread
	until ABSL_ANNOTATE_IGNORE_READS_END is called.
	Useful to ignore intentional racey reads, while still checking
	other reads and all writes.
	See also ABSL_ANNOTATE_UNPROTECTED_READ. */
	#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
	AbslAnnotateIgnoreReadsBegin(__FILE__, __LINE__)

	/* Stop ignoring reads. */
	#define ABSL_ANNOTATE_IGNORE_READS_END() \
	AbslAnnotateIgnoreReadsEnd(__FILE__, __LINE__)

	/* Similar to ABSL_ANNOTATE_IGNORE_READS_BEGIN, but ignore writes instead. */
	#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
	AbslAnnotateIgnoreWritesBegin(__FILE__, __LINE__)

	/* Stop ignoring writes. */
	#define ABSL_ANNOTATE_IGNORE_WRITES_END() \
	AbslAnnotateIgnoreWritesEnd(__FILE__, __LINE__)

	/* Clang provides limited support for static thread-safety analysis
	through a feature called Annotalysis. We configure macro-definitions
	according to whether Annotalysis support is available. */
	#elif defined(ABSL_ANNOTALYSIS_ENABLED)

	#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
	AbslStaticAnnotateIgnoreReadsBegin(__FILE__, __LINE__)

	#define ABSL_ANNOTATE_IGNORE_READS_END() \
	AbslStaticAnnotateIgnoreReadsEnd(__FILE__, __LINE__)

	#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
	AbslStaticAnnotateIgnoreWritesBegin(__FILE__, __LINE__)

	#define ABSL_ANNOTATE_IGNORE_WRITES_END() \
	AbslStaticAnnotateIgnoreWritesEnd(__FILE__, __LINE__)

	#else
	#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() /* empty */
	#define ABSL_ANNOTATE_IGNORE_READS_END() /* empty */
	#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() /* empty */
	#define ABSL_ANNOTATE_IGNORE_WRITES_END() /* empty */
	#endif

	/* Implement the ANNOTATE_IGNORE_READS_AND_WRITES_* annotations using the more
	primitive annotations defined above. */
	#if defined(ABSL_ANNOTATIONS_ENABLED)

	/* Start ignoring all memory accesses (both reads and writes). */
	#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() \
	do { \
	ABSL_ANNOTATE_IGNORE_READS_BEGIN(); \
	ABSL_ANNOTATE_IGNORE_WRITES_BEGIN(); \
	}while (0)

	/* Stop ignoring both reads and writes. */
	#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END() \
	do { \
	ABSL_ANNOTATE_IGNORE_WRITES_END(); \
	ABSL_ANNOTATE_IGNORE_READS_END(); \
	}while (0)

	#else
	#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() /* empty */
	#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END() /* empty */
	#endif

	/* Use the macros above rather than using these functions directly. */
	#include <stddef.h>
	#ifdef __cplusplus
	extern "C" {
	#endif
	void AbslAnnotateRWLockCreate(const char *file, int line,
	const volatile void *lock);
	void AbslAnnotateRWLockCreateStatic(const char *file, int line,
	const volatile void *lock);
	void AbslAnnotateRWLockDestroy(const char *file, int line,
	const volatile void *lock);
	void AbslAnnotateRWLockAcquired(const char *file, int line,
	const volatile void lock, long is_w); / NOLINT */
	void AbslAnnotateRWLockReleased(const char *file, int line,
	const volatile void lock, long is_w); / NOLINT */
	void AbslAnnotateBenignRace(const char *file, int line,
	const volatile void *address,
	const char *description);
	void AbslAnnotateBenignRaceSized(const char *file, int line,
	const volatile void *address,
	size_t size,
	const char *description);
	void AbslAnnotateThreadName(const char *file, int line,
	const char *name);
	void AbslAnnotateEnableRaceDetection(const char *file, int line, int enable);
	void AbslAnnotateMemoryIsInitialized(const char *file, int line,
	const volatile void *mem, size_t size);
	void AbslAnnotateMemoryIsUninitialized(const char *file, int line,
	const volatile void *mem, size_t size);

	/* Annotations expand to these functions, when Dynamic Annotations are enabled.
	These functions are either implemented as no-op calls, if no Sanitizer is
	attached, or provided with externally-linked implementations by a library
	like ThreadSanitizer. */
	void AbslAnnotateIgnoreReadsBegin(const char *file, int line)
	ABSL_ATTRIBUTE_IGNORE_READS_BEGIN;
	void AbslAnnotateIgnoreReadsEnd(const char *file, int line)
	ABSL_ATTRIBUTE_IGNORE_READS_END;
	void AbslAnnotateIgnoreWritesBegin(const char *file, int line);
	void AbslAnnotateIgnoreWritesEnd(const char *file, int line);

	#if defined(ABSL_ANNOTALYSIS_ENABLED)
	/* When Annotalysis is enabled without Dynamic Annotations, the use of
	static-inline functions allows the annotations to be read at compile-time,
	while still letting the compiler elide the functions from the final build.

	TODO(delesley) -- The exclusive lock here ignores writes as well, but
	allows IGNORE_READS_AND_WRITES to work properly. */
	#pragma GCC diagnostic push
	#pragma GCC diagnostic ignored "-Wunused-function"
	static inline void AbslStaticAnnotateIgnoreReadsBegin(const char *file, int line)
	ABSL_ATTRIBUTE_IGNORE_READS_BEGIN { (void)file; (void)line; }
	static inline void AbslStaticAnnotateIgnoreReadsEnd(const char *file, int line)
	ABSL_ATTRIBUTE_IGNORE_READS_END { (void)file; (void)line; }
	static inline void AbslStaticAnnotateIgnoreWritesBegin(
	const char *file, int line) { (void)file; (void)line; }
	static inline void AbslStaticAnnotateIgnoreWritesEnd(
	const char *file, int line) { (void)file; (void)line; }
	#pragma GCC diagnostic pop
	#endif

	/* Return non-zero value if running under valgrind.

	If "valgrind.h" is included into dynamic_annotations.cc,
	the regular valgrind mechanism will be used.
	See http://valgrind.org/docs/manual/manual-core-adv.html about
	RUNNING_ON_VALGRIND and other valgrind "client requests".
	The file "valgrind.h" may be obtained by doing
	svn co svn://svn.valgrind.org/valgrind/trunk/include

	If for some reason you can't use "valgrind.h" or want to fake valgrind,
	there are two ways to make this function return non-zero:
	- Use environment variable: export RUNNING_ON_VALGRIND=1
	- Make your tool intercept the function AbslRunningOnValgrind() and
	change its return value.
	*/
	int AbslRunningOnValgrind(void);

	/* AbslValgrindSlowdown returns:
	* 1.0, if (AbslRunningOnValgrind() == 0)
	* 50.0, if (AbslRunningOnValgrind() != 0 && getenv("VALGRIND_SLOWDOWN") == NULL)
	* atof(getenv("VALGRIND_SLOWDOWN")) otherwise
	This function can be used to scale timeout values:
	EXAMPLE:
	for (;;) {
	DoExpensiveBackgroundTask();
	SleepForSeconds(5 * AbslValgrindSlowdown());
	}
	*/
	double AbslValgrindSlowdown(void);

	#ifdef __cplusplus
	}
	#endif

	/* ABSL_ANNOTATE_UNPROTECTED_READ is the preferred way to annotate racey reads.

	Instead of doing
	ABSL_ANNOTATE_IGNORE_READS_BEGIN();
	... = x;
	ABSL_ANNOTATE_IGNORE_READS_END();
	one can use
	... = ABSL_ANNOTATE_UNPROTECTED_READ(x); */
	#if defined(__cplusplus) && defined(ABSL_ANNOTATIONS_ENABLED)
	template <typename T>
	inline T ABSL_ANNOTATE_UNPROTECTED_READ(const volatile T &x) { /* NOLINT */
	ABSL_ANNOTATE_IGNORE_READS_BEGIN();
	T res = x;
	ABSL_ANNOTATE_IGNORE_READS_END();
	return res;
	}
	#else
	#define ABSL_ANNOTATE_UNPROTECTED_READ(x) (x)
	#endif

	#if ABSL_DYNAMIC_ANNOTATIONS_ENABLED != 0 && defined(__cplusplus)
	/* Apply ABSL_ANNOTATE_BENIGN_RACE_SIZED to a static variable. */
	#define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description) \
	namespace { \
	class static_var ## _annotator { \
	public: \
	static_var ## _annotator() { \
	ABSL_ANNOTATE_BENIGN_RACE_SIZED(&static_var, \
	sizeof(static_var), \
	# static_var ": " description); \
	} \
	}; \
	static static_var ## _annotator the ## static_var ## _annotator;\
	} // namespace
	#else /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED == 0 */
	#define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description) /* empty */
	#endif /* ABSL_DYNAMIC_ANNOTATIONS_ENABLED */

	#ifdef ADDRESS_SANITIZER
	/* Describe the current state of a contiguous container such as e.g.
	* std::vector or std::string. For more details see
	* sanitizer/common_interface_defs.h, which is provided by the compiler. */
	#include <sanitizer/common_interface_defs.h>
	#define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid) \
	__sanitizer_annotate_contiguous_container(beg, end, old_mid, new_mid)
	#define ABSL_ADDRESS_SANITIZER_REDZONE(name) \
	struct { char x[8] __attribute__ ((aligned (8))); } name
	#else
	#define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid)
	#define ABSL_ADDRESS_SANITIZER_REDZONE(name)
	#endif // ADDRESS_SANITIZER

	/* Undefine the macros intended only in this file. */
	#undef ABSL_ANNOTALYSIS_ENABLED
	#undef ABSL_ANNOTATIONS_ENABLED
	#undef ABSL_ATTRIBUTE_IGNORE_READS_BEGIN
	#undef ABSL_ATTRIBUTE_IGNORE_READS_END

	#endif /* ABSL_BASE_DYNAMIC_ANNOTATIONS_H_ */