chromium/third_party/perfetto/include/perfetto/base/compiler.h

/*
 * Copyright (C) 2019 The Android Open Source Project
 *
 * 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
 *
 *      http://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.
 */

#ifndef INCLUDE_PERFETTO_BASE_COMPILER_H_
#define INCLUDE_PERFETTO_BASE_COMPILER_H_

#include <stddef.h>
#include <type_traits>

#include "perfetto/public/compiler.h"

// __has_attribute is supported only by clang and recent versions of GCC.
// Add a layer to wrap the __has_attribute macro.
#if defined(__has_attribute)
#define PERFETTO_HAS_ATTRIBUTE(x) …
#else
#define PERFETTO_HAS_ATTRIBUTE …
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_WARN_UNUSED_RESULT …
#else
#define PERFETTO_WARN_UNUSED_RESULT
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_UNUSED …
#else
#define PERFETTO_UNUSED
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_NORETURN …
#else
#define PERFETTO_NORETURN …
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_DEBUG_FUNCTION_IDENTIFIER() …
#elif defined(_MSC_VER)
#define PERFETTO_DEBUG_FUNCTION_IDENTIFIER …
#else
#define PERFETTO_DEBUG_FUNCTION_IDENTIFIER …
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_PRINTF_FORMAT(x, y) …
#else
#define PERFETTO_PRINTF_FORMAT …
#endif

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_POPCOUNT(x) …
#else
#include <intrin.h>
#define PERFETTO_POPCOUNT …
#endif

#if defined(__clang__)
#if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__)
extern "C" void __asan_poison_memory_region(void const volatile*, size_t);
extern "C" void __asan_unpoison_memory_region(void const volatile*, size_t);
#define PERFETTO_ASAN_POISON …
#define PERFETTO_ASAN_UNPOISON …
#else
#define PERFETTO_ASAN_POISON(addr, size) …
#define PERFETTO_ASAN_UNPOISON(addr, size) …
#endif  // __has_feature(address_sanitizer)
#else
#define PERFETTO_ASAN_POISON …
#define PERFETTO_ASAN_UNPOISON …
#endif  // __clang__

#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_IS_LITTLE_ENDIAN() …
#else
// Assume all MSVC targets are little endian.
#define PERFETTO_IS_LITTLE_ENDIAN …
#endif

// This is used for exporting xxxMain() symbols (e.g., PerfettoCmdMain,
// ProbesMain) from libperfetto.so when the GN arg monolithic_binaries = false.
#if defined(__GNUC__) || defined(__clang__)
#define PERFETTO_EXPORT_ENTRYPOINT …
#else
// TODO(primiano): on Windows this should be a pair of dllexport/dllimport. But
// that requires a -DXXX_IMPLEMENTATION depending on whether we are on the
// impl-site or call-site. Right now it's not worth the trouble as we
// force-export the xxxMain() symbols only on Android, where we pack all the
// code for N binaries into one .so to save binary size. On Windows we support
// only monolithic binaries, as they are easier to deal with.
#define PERFETTO_EXPORT_ENTRYPOINT
#endif

// Disables thread safety analysis for functions where the compiler can't
// accurate figure out which locks are being held.
#if defined(__clang__)
#define PERFETTO_NO_THREAD_SAFETY_ANALYSIS …
#else
#define PERFETTO_NO_THREAD_SAFETY_ANALYSIS
#endif

// Disables undefined behavior analysis for a function.
#if defined(__clang__)
#define PERFETTO_NO_SANITIZE_UNDEFINED …
#else
#define PERFETTO_NO_SANITIZE_UNDEFINED
#endif

// Avoid calling the exit-time destructor on an object with static lifetime.
#if PERFETTO_HAS_ATTRIBUTE(no_destroy)
#define PERFETTO_HAS_NO_DESTROY() …
#define PERFETTO_NO_DESTROY …
#else
#define PERFETTO_HAS_NO_DESTROY …
#define PERFETTO_NO_DESTROY
#endif

// Macro for telling -Wimplicit-fallthrough that a fallthrough is intentional.
#define PERFETTO_FALLTHROUGH …

namespace perfetto {
namespace base {

template <typename... T>
inline void ignore_result(const T&...) { … }

}  // namespace base
}  // namespace perfetto

#endif  // INCLUDE_PERFETTO_BASE_COMPILER_H_