diff options
| -rw-r--r-- | absl/base/internal/raw_logging.h | 14 | ||||
| -rw-r--r-- | absl/base/macros.h | 11 | ||||
| -rw-r--r-- | absl/status/internal/statusor_internal.h | 9 | ||||
| -rw-r--r-- | absl/strings/internal/str_split_internal.h | 51 |
4 files changed, 40 insertions, 45 deletions
diff --git a/absl/base/internal/raw_logging.h b/absl/base/internal/raw_logging.h index 2508f3cf..20f4291b 100644 --- a/absl/base/internal/raw_logging.h +++ b/absl/base/internal/raw_logging.h @@ -72,12 +72,14 @@ // // The API is a subset of the above: each macro only takes two arguments. Use // StrCat if you need to build a richer message. -#define ABSL_INTERNAL_LOG(severity, message) \ - do { \ - constexpr const char* absl_raw_logging_internal_filename = __FILE__; \ - ::absl::raw_logging_internal::internal_log_function( \ - ABSL_RAW_LOGGING_INTERNAL_##severity, \ - absl_raw_logging_internal_filename, __LINE__, message); \ +#define ABSL_INTERNAL_LOG(severity, message) \ + do { \ + constexpr const char* absl_raw_logging_internal_filename = __FILE__; \ + ::absl::raw_logging_internal::internal_log_function( \ + ABSL_RAW_LOGGING_INTERNAL_##severity, \ + absl_raw_logging_internal_filename, __LINE__, message); \ + if (ABSL_RAW_LOGGING_INTERNAL_##severity == ::absl::LogSeverity::kFatal) \ + ABSL_INTERNAL_UNREACHABLE; \ } while (0) #define ABSL_INTERNAL_CHECK(condition, message) \ diff --git a/absl/base/macros.h b/absl/base/macros.h index 02dd9ff4..3e085a91 100644 --- a/absl/base/macros.h +++ b/absl/base/macros.h @@ -144,4 +144,15 @@ ABSL_NAMESPACE_END #define ABSL_INTERNAL_RETHROW do {} while (false) #endif // ABSL_HAVE_EXCEPTIONS +// `ABSL_INTERNAL_UNREACHABLE` is an unreachable statement. A program which +// reaches one has undefined behavior, and the compiler may optimize +// accordingly. +#if defined(__GNUC__) || ABSL_HAVE_BUILTIN(__builtin_unreachable) +#define ABSL_INTERNAL_UNREACHABLE __builtin_unreachable() +#elif defined(_MSC_VER) +#define ABSL_INTERNAL_UNREACHABLE __assume(0) +#else +#define ABSL_INTERNAL_UNREACHABLE +#endif + #endif // ABSL_BASE_MACROS_H_ diff --git a/absl/status/internal/statusor_internal.h b/absl/status/internal/statusor_internal.h index 7cc76256..eaac2c0b 100644 --- a/absl/status/internal/statusor_internal.h +++ b/absl/status/internal/statusor_internal.h @@ -17,6 +17,7 @@ #include <type_traits> #include <utility> +#include "absl/base/attributes.h" #include "absl/meta/type_traits.h" #include "absl/status/status.h" #include "absl/utility/utility.h" @@ -135,18 +136,14 @@ class Helper { public: // Move type-agnostic error handling to the .cc. static void HandleInvalidStatusCtorArg(Status*); - static void Crash(const absl::Status& status); + ABSL_ATTRIBUTE_NORETURN static void Crash(const absl::Status& status); }; // Construct an instance of T in `p` through placement new, passing Args... to // the constructor. // This abstraction is here mostly for the gcc performance fix. template <typename T, typename... Args> -void PlacementNew(void* p, Args&&... args) { -#if defined(__GNUC__) && !defined(__clang__) - // Teach gcc that 'p' cannot be null, fixing code size issues. - if (p == nullptr) __builtin_unreachable(); -#endif +ABSL_ATTRIBUTE_NONNULL(1) void PlacementNew(void* p, Args&&... args) { new (p) T(std::forward<Args>(args)...); } diff --git a/absl/strings/internal/str_split_internal.h b/absl/strings/internal/str_split_internal.h index 76924771..49ec5392 100644 --- a/absl/strings/internal/str_split_internal.h +++ b/absl/strings/internal/str_split_internal.h @@ -66,56 +66,41 @@ class ConvertibleToStringView { // Matches rvalue strings and moves their data to a member. ConvertibleToStringView(std::string&& s) // NOLINT(runtime/explicit) - : copy_(std::move(s)), value_(copy_), self_referential_(true) {} + : copy_(std::move(s)), value_(copy_) {} ConvertibleToStringView(const ConvertibleToStringView& other) - : value_(other.value_), self_referential_(other.self_referential_) { - if (other.self_referential_) { - new (©_) std::string(other.copy_); - value_ = copy_; - } - } + : copy_(other.copy_), + value_(other.IsSelfReferential() ? copy_ : other.value_) {} - ConvertibleToStringView(ConvertibleToStringView&& other) - : value_(other.value_), self_referential_(other.self_referential_) { - if (other.self_referential_) { - new (©_) std::string(std::move(other.copy_)); - value_ = copy_; - } + ConvertibleToStringView(ConvertibleToStringView&& other) { + StealMembers(std::move(other)); } ConvertibleToStringView& operator=(ConvertibleToStringView other) { - this->~ConvertibleToStringView(); - new (this) ConvertibleToStringView(std::move(other)); + StealMembers(std::move(other)); return *this; } absl::string_view value() const { return value_; } - ~ConvertibleToStringView() { MaybeReleaseCopy(); } - private: - void MaybeReleaseCopy() { - if (self_referential_) { - // An explicit destructor call cannot be a qualified name such as - // std::string. The "using" declaration works around this - // issue by creating an unqualified name for the destructor. - using string_type = std::string; - copy_.~string_type(); + // Returns true if ctsp's value refers to its internal copy_ member. + bool IsSelfReferential() const { return value_.data() == copy_.data(); } + + void StealMembers(ConvertibleToStringView&& other) { + if (other.IsSelfReferential()) { + copy_ = std::move(other.copy_); + value_ = copy_; + other.value_ = other.copy_; + } else { + value_ = other.value_; } } - struct Unused { // MSVC disallows unions with only 1 member. - }; + // Holds the data moved from temporary std::string arguments. Declared first // so that 'value' can refer to 'copy_'. - union { - std::string copy_; - Unused unused_; - }; - + std::string copy_; absl::string_view value_; - // true if value_ refers to the internal copy_ member. - bool self_referential_ = false; }; // An iterator that enumerates the parts of a string from a Splitter. The text |