// 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_
#include <stddef.h>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#ifdef __cplusplus
#include "absl/base/macros.h"
#endif
// TODO(rogeeff): Remove after the backward compatibility period.
#include "absl/base/internal/dynamic_annotations.h" // IWYU pragma: export
// -------------------------------------------------------------------------
// Decide which features are enabled.
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 0
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED 1
#else
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 0
// 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. When running in opt-mode, GCC
// will issue a warning, if these attributes are compiled. Only include them
// when compiling using Clang.
#if defined(__clang__)
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 1
#if !defined(SWIG)
#define ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED 1
#endif
#else
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 0
#endif
// Read/write annotations are enabled in Annotalysis mode; disabled otherwise.
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED \
ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#endif // ABSL_HAVE_THREAD_SANITIZER
#ifdef __cplusplus
#define ABSL_INTERNAL_BEGIN_EXTERN_C extern "C" {
#define ABSL_INTERNAL_END_EXTERN_C } // extern "C"
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) ::F
#define ABSL_INTERNAL_STATIC_INLINE inline
#else
#define ABSL_INTERNAL_BEGIN_EXTERN_C // empty
#define ABSL_INTERNAL_END_EXTERN_C // empty
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) F
#define ABSL_INTERNAL_STATIC_INLINE static inline
#endif
// -------------------------------------------------------------------------
// Define race annotations.
#if ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED == 1
// -------------------------------------------------------------
// 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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateEnableRaceDetection) \
(__FILE__, __LINE__, enable)
// -------------------------------------------------------------
// Annotations useful for debugging.
// Report the current thread `name` to a race detector.
#define ABSL_ANNOTATE_THREAD_NAME(name) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateThreadName)(__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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreate)(__FILE__, __LINE__, lock)
// Report that a linker initialized lock has been created at address `lock`.
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreateStatic) \
(__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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockDestroy)(__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) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockAcquired) \
(__FILE__, __LINE__, lock, is_w)
// Report that the lock at address `lock` is about to be released.
// `is_w`=1 for writer lock, `is_w`=0 for reader lock.
#define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockReleased) \
(__FILE__, __LINE__, lock, is_w)
// Apply ABSL_ANNOTATE_BENIGN_RACE_SIZED to a static variable `static_var`.
#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
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateRWLockCreate(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockCreateStatic(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockDestroy(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockAcquired(const char* file, int line,
const volatile void* lock, long is_w); // NOLINT
void AnnotateRWLockReleased(const char* file, int line,
const volatile void* lock, long is_w); // NOLINT
void AnnotateBenignRace(const char* file, int line,
const volatile void* address, const char* description);
void AnnotateBenignRaceSized(const char* file, int line,
const volatile void* address, size_t size,
const char* description);
void AnnotateThreadName(const char* file, int line, const char* name);
void AnnotateEnableRaceDetection(const char* file, int line, int enable);
ABSL_INTERNAL_END_EXTERN_C
#else // ABSL_INTERNAL_RACE_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
#define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description) // empty
#endif // ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
// -------------------------------------------------------------------------
// Define memory annotations.
#ifdef ABSL_HAVE_MEMORY_SANITIZER
#include <sanitizer/msan_interface.h>
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
__msan_unpoison(address, size)
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
__msan_allocated_memory(address, size)
#else // !defined(ABSL_HAVE_MEMORY_SANITIZER)
// TODO(rogeeff): remove this branch
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#else
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) // empty
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) // empty
#endif
#endif // ABSL_HAVE_MEMORY_SANITIZER
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END attributes.
#if defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE \
__attribute((exclusive_lock_function("*")))
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE \
__attribute((unlock_function("*")))
#else // !defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE // empty
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE // empty
#endif // defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END annotations.
#if ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED == 1
// 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() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsBegin)(__FILE__, __LINE__)
// Stop ignoring reads.
#define ABSL_ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsEnd)(__FILE__, __LINE__)
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateIgnoreReadsBegin(const char* file, int line)
ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE;
void AnnotateIgnoreReadsEnd(const char* file,
int line) ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE;
ABSL_INTERNAL_END_EXTERN_C
#elif defined(ABSL_INTERNAL_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.
#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AbslInternalAnnotateIgnoreReadsBegin)()
#define ABSL_ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AbslInternalAnnotateIgnoreReadsEnd)()
ABSL_INTERNAL_STATIC_INLINE void AbslInternalAnnotateIgnoreReadsBegin()
ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE {}
ABSL_INTERNAL_STATIC_INLINE void AbslInternalAnnotateIgnoreReadsEnd()
ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE {}
#else
#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_READS_END() // empty
#endif
// -------------------------------------------------------------------------
// Define IGNORE_WRITES_BEGIN/_END annotations.
#if ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED == 1
// Similar to ABSL_ANNOTATE_IGNORE_READS_BEGIN, but ignore writes instead.
#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesBegin)(__FILE__, __LINE__)
// Stop ignoring writes.
#define ABSL_ANNOTATE_IGNORE_WRITES_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesEnd)(__FILE__, __LINE__)
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateIgnoreWritesBegin(const char* file, int line);
void AnnotateIgnoreWritesEnd(const char* file, int line);
ABSL_INTERNAL_END_EXTERN_C
#else
#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_WRITES_END() // empty
#endif
// -------------------------------------------------------------------------
// Define the ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_* annotations using the more
// primitive annotations defined above.
//
// Instead of doing
// ABSL_ANNOTATE_IGNORE_READS_BEGIN();
// ... = x;
// ABSL_ANNOTATE_IGNORE_READS_END();
// one can use
// ... = ABSL_ANNOTATE_UNPROTECTED_READ(x);
#if defined(ABSL_INTERNAL_READS_WRITES_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)
#ifdef __cplusplus
// ABSL_ANNOTATE_UNPROTECTED_READ is the preferred way to annotate racey reads.
#define ABSL_ANNOTATE_UNPROTECTED_READ(x) \
absl::base_internal::AnnotateUnprotectedRead(x)
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
template <typename T>
inline T AnnotateUnprotectedRead(const volatile T& x) { // NOLINT
ABSL_ANNOTATE_IGNORE_READS_BEGIN();
T res = x;
ABSL_ANNOTATE_IGNORE_READS_END();
return res;
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif
#else
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END() // empty
#define ABSL_ANNOTATE_UNPROTECTED_READ(x) (x)
#endif
#ifdef __cplusplus
#ifdef ABSL_HAVE_THREAD_SANITIZER
ABSL_INTERNAL_BEGIN_EXTERN_C
int RunningOnValgrind();
double ValgrindSlowdown();
ABSL_INTERNAL_END_EXTERN_C
#else
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
ABSL_DEPRECATED(
"Don't use this interface. It is misleading and is being deleted.")
ABSL_ATTRIBUTE_ALWAYS_INLINE inline int RunningOnValgrind() { return 0; }
ABSL_DEPRECATED(
"Don't use this interface. It is misleading and is being deleted.")
ABSL_ATTRIBUTE_ALWAYS_INLINE inline double ValgrindSlowdown() { return 1.0; }
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
using absl::base_internal::RunningOnValgrind;
using absl::base_internal::ValgrindSlowdown;
#endif
#endif
// -------------------------------------------------------------------------
// Address sanitizer annotations
#ifdef ABSL_HAVE_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) // empty
#define ABSL_ADDRESS_SANITIZER_REDZONE(name) static_assert(true, "")
#endif // ABSL_HAVE_ADDRESS_SANITIZER
// -------------------------------------------------------------------------
// Undefine the macros intended only for this file.
#undef ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#undef ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_BEGIN_EXTERN_C
#undef ABSL_INTERNAL_END_EXTERN_C
#undef ABSL_INTERNAL_STATIC_INLINE
#endif // ABSL_BASE_DYNAMIC_ANNOTATIONS_H_
