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-rw-r--r--absl/base/config.h22
-rw-r--r--absl/flags/flag.h21
-rw-r--r--absl/flags/internal/registry.cc80
-rw-r--r--absl/flags/internal/registry.h3
-rw-r--r--absl/random/internal/salted_seed_seq.h63
5 files changed, 67 insertions, 122 deletions
diff --git a/absl/base/config.h b/absl/base/config.h
index 406a931f..692738e3 100644
--- a/absl/base/config.h
+++ b/absl/base/config.h
@@ -370,16 +370,20 @@
#error "absl endian detection needs to be set up for your compiler"
#endif
-// MacOS 10.13 doesn't let you use <any>, <optional>, or <variant> even though
-// the headers exist and are publicly noted to work. See
+// MacOS 10.13 and iOS 10.11 don't let you use <any>, <optional>, or <variant>
+// even though the headers exist and are publicly noted to work. See
// https://github.com/abseil/abseil-cpp/issues/207 and
// https://developer.apple.com/documentation/xcode_release_notes/xcode_10_release_notes
+// libc++ spells out the availability requirements in the file
+// llvm-project/libcxx/include/__config.
#if defined(__APPLE__) && defined(_LIBCPP_VERSION) && \
- defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
- __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101400
-#define ABSL_INTERNAL_MACOS_CXX17_TYPES_UNAVAILABLE 1
+ ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
+ __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101400) || \
+ (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) && \
+ __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 101200))
+#define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 1
#else
-#define ABSL_INTERNAL_MACOS_CXX17_TYPES_UNAVAILABLE 0
+#define ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE 0
#endif
// ABSL_HAVE_STD_ANY
@@ -391,7 +395,7 @@
#ifdef __has_include
#if __has_include(<any>) && __cplusplus >= 201703L && \
- !ABSL_INTERNAL_MACOS_CXX17_TYPES_UNAVAILABLE
+ !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
#define ABSL_HAVE_STD_ANY 1
#endif
#endif
@@ -405,7 +409,7 @@
#ifdef __has_include
#if __has_include(<optional>) && __cplusplus >= 201703L && \
- !ABSL_INTERNAL_MACOS_CXX17_TYPES_UNAVAILABLE
+ !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
#define ABSL_HAVE_STD_OPTIONAL 1
#endif
#endif
@@ -419,7 +423,7 @@
#ifdef __has_include
#if __has_include(<variant>) && __cplusplus >= 201703L && \
- !ABSL_INTERNAL_MACOS_CXX17_TYPES_UNAVAILABLE
+ !ABSL_INTERNAL_APPLE_CXX17_TYPES_UNAVAILABLE
#define ABSL_HAVE_STD_VARIANT 1
#endif
#endif
diff --git a/absl/flags/flag.h b/absl/flags/flag.h
index c70023ab..6c9f4876 100644
--- a/absl/flags/flag.h
+++ b/absl/flags/flag.h
@@ -216,17 +216,16 @@ void SetFlag(absl::Flag<T>* flag, const V& v) {
// Note: Name of registrar object is not arbitrary. It is used to "grab"
// global name for FLAGS_no<flag_name> symbol, thus preventing the possibility
// of defining two flags with names foo and nofoo.
-#define ABSL_FLAG_IMPL(Type, name, default_value, help) \
- namespace absl {} \
- ABSL_FLAG_IMPL_DECLARE_DEF_VAL_WRAPPER(name, Type, default_value) \
- ABSL_FLAG_IMPL_DECLARE_HELP_WRAPPER(name, help) \
- absl::Flag<Type> FLAGS_##name( \
- ABSL_FLAG_IMPL_FLAGNAME(#name), \
- &AbslFlagsWrapHelp##name, \
- ABSL_FLAG_IMPL_FILENAME(), \
- &absl::flags_internal::FlagMarshallingOps<Type>, \
- &AbslFlagsInitFlag##name); \
- extern bool FLAGS_no##name; \
+#define ABSL_FLAG_IMPL(Type, name, default_value, help) \
+ namespace absl {} \
+ ABSL_FLAG_IMPL_DECLARE_DEF_VAL_WRAPPER(name, Type, default_value) \
+ ABSL_FLAG_IMPL_DECLARE_HELP_WRAPPER(name, help) \
+ ABSL_CONST_INIT absl::Flag<Type> FLAGS_##name( \
+ ABSL_FLAG_IMPL_FLAGNAME(#name), &AbslFlagsWrapHelp##name, \
+ ABSL_FLAG_IMPL_FILENAME(), \
+ &absl::flags_internal::FlagMarshallingOps<Type>, \
+ &AbslFlagsInitFlag##name); \
+ extern bool FLAGS_no##name; \
bool FLAGS_no##name = ABSL_FLAG_IMPL_REGISTRAR(Type, FLAGS_##name)
// ABSL_RETIRED_FLAG
diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc
index f37871c9..4e5d1106 100644
--- a/absl/flags/internal/registry.cc
+++ b/absl/flags/internal/registry.cc
@@ -54,53 +54,6 @@ void DestroyFlag(CommandLineFlag* flag) NO_THREAD_SAFETY_ANALYSIS {
// the function will acquire it itself if needed.
// --------------------------------------------------------------------
-// A map from flag pointer to CommandLineFlag*. Used when registering
-// validators.
-class FlagPtrMap {
- public:
- void Register(CommandLineFlag* flag) {
- auto& vec = buckets_[BucketForFlag(flag->cur)];
- if (vec.size() == vec.capacity()) {
- // Bypass default 2x growth factor with 1.25 so we have fuller vectors.
- // This saves 4% memory compared to default growth.
- vec.reserve(vec.size() * 1.25 + 0.5);
- }
- vec.push_back(flag);
- }
-
- CommandLineFlag* FindByPtr(const void* flag_ptr) {
- const auto& flag_vector = buckets_[BucketForFlag(flag_ptr)];
- for (CommandLineFlag* entry : flag_vector) {
- if (entry->cur == flag_ptr) {
- return entry;
- }
- }
- return nullptr;
- }
-
- private:
- // Instead of std::map, we use a custom hash table where each bucket stores
- // flags in a vector. This reduces memory usage 40% of the memory that would
- // have been used by std::map.
- //
- // kNumBuckets was picked as a large enough prime. As of writing this code, a
- // typical large binary has ~8k (old-style) flags, and this would gives
- // buckets with roughly 50 elements each.
- //
- // Note that reads to this hash table are rare: exactly as many as we have
- // flags with validators. As of writing, a typical binary only registers 52
- // validated flags.
- static constexpr size_t kNumBuckets = 163;
- std::vector<CommandLineFlag*> buckets_[kNumBuckets];
-
- static int BucketForFlag(const void* ptr) {
- // Modulo a prime is good enough here. On a real program, bucket size stddev
- // after registering 8k flags is ~5 (mean size at 51).
- return reinterpret_cast<uintptr_t>(ptr) % kNumBuckets;
- }
-};
-constexpr size_t FlagPtrMap::kNumBuckets;
-
class FlagRegistry {
public:
FlagRegistry() = default;
@@ -111,9 +64,7 @@ class FlagRegistry {
}
// Store a flag in this registry. Takes ownership of *flag.
- // If ptr is non-null, the flag can later be found by calling
- // FindFlagViaPtrLocked(ptr).
- void RegisterFlag(CommandLineFlag* flag, const void* ptr);
+ void RegisterFlag(CommandLineFlag* flag);
void Lock() EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); }
void Unlock() UNLOCK_FUNCTION(lock_) { lock_.Unlock(); }
@@ -126,9 +77,6 @@ class FlagRegistry {
// found or not retired. Does not emit a warning.
CommandLineFlag* FindRetiredFlagLocked(absl::string_view name);
- // Returns the flag object whose current-value is stored at flag_ptr.
- CommandLineFlag* FindFlagViaPtrLocked(const void* flag_ptr);
-
static FlagRegistry* GlobalRegistry(); // returns a singleton registry
private:
@@ -142,8 +90,6 @@ class FlagRegistry {
using FlagConstIterator = FlagMap::const_iterator;
FlagMap flags_;
- FlagPtrMap flag_ptr_map_;
-
absl::Mutex lock_;
// Disallow
@@ -169,7 +115,7 @@ class FlagRegistryLock {
} // namespace
-void FlagRegistry::RegisterFlag(CommandLineFlag* flag, const void* ptr) {
+void FlagRegistry::RegisterFlag(CommandLineFlag* flag) {
FlagRegistryLock registry_lock(this);
std::pair<FlagIterator, bool> ins =
flags_.insert(FlagMap::value_type(flag->Name(), flag));
@@ -217,11 +163,6 @@ void FlagRegistry::RegisterFlag(CommandLineFlag* flag, const void* ptr) {
// All cases above are fatal, except for the retired flags.
std::exit(1);
}
-
- if (ptr != nullptr) {
- // This must be the first time we're seeing this flag.
- flag_ptr_map_.Register(flag);
- }
}
CommandLineFlag* FlagRegistry::FindFlagLocked(absl::string_view name) {
@@ -247,10 +188,6 @@ CommandLineFlag* FlagRegistry::FindRetiredFlagLocked(absl::string_view name) {
return i->second;
}
-CommandLineFlag* FlagRegistry::FindFlagViaPtrLocked(const void* flag_ptr) {
- return flag_ptr_map_.FindByPtr(flag_ptr);
-}
-
// --------------------------------------------------------------------
// FlagSaver
// FlagSaverImpl
@@ -430,13 +367,6 @@ CommandLineFlag* FindCommandLineFlag(absl::string_view name) {
return registry->FindFlagLocked(name);
}
-CommandLineFlag* FindCommandLineV1Flag(const void* flag_ptr) {
- FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
- FlagRegistryLock frl(registry);
-
- return registry->FindFlagViaPtrLocked(flag_ptr);
-}
-
CommandLineFlag* FindRetiredFlag(absl::string_view name) {
FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
FlagRegistryLock frl(registry);
@@ -477,8 +407,8 @@ void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT) {
// --------------------------------------------------------------------
-bool RegisterCommandLineFlag(CommandLineFlag* flag, const void* ptr) {
- FlagRegistry::GlobalRegistry()->RegisterFlag(flag, ptr);
+bool RegisterCommandLineFlag(CommandLineFlag* flag) {
+ FlagRegistry::GlobalRegistry()->RegisterFlag(flag);
return true;
}
@@ -492,7 +422,7 @@ bool Retire(FlagOpFn ops, FlagMarshallingOpFn marshalling_ops,
/*filename_arg=*/"RETIRED", ops, marshalling_ops,
/*initial_value_gen=*/nullptr,
/*retired_arg=*/true, nullptr, nullptr);
- FlagRegistry::GlobalRegistry()->RegisterFlag(flag, nullptr);
+ FlagRegistry::GlobalRegistry()->RegisterFlag(flag);
return true;
}
diff --git a/absl/flags/internal/registry.h b/absl/flags/internal/registry.h
index bd141e1e..27566fbf 100644
--- a/absl/flags/internal/registry.h
+++ b/absl/flags/internal/registry.h
@@ -57,7 +57,6 @@ void FillCommandLineFlagInfo(CommandLineFlag* flag,
//-----------------------------------------------------------------------------
CommandLineFlag* FindCommandLineFlag(absl::string_view name);
-CommandLineFlag* FindCommandLineV1Flag(const void* flag_ptr);
CommandLineFlag* FindRetiredFlag(absl::string_view name);
// Executes specified visitor for each non-retired flag in the registry.
@@ -74,7 +73,7 @@ void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT);
//-----------------------------------------------------------------------------
-bool RegisterCommandLineFlag(CommandLineFlag*, const void* ptr = nullptr);
+bool RegisterCommandLineFlag(CommandLineFlag*);
//-----------------------------------------------------------------------------
// Retired registrations:
diff --git a/absl/random/internal/salted_seed_seq.h b/absl/random/internal/salted_seed_seq.h
index 3d16cf97..e160f79e 100644
--- a/absl/random/internal/salted_seed_seq.h
+++ b/absl/random/internal/salted_seed_seq.h
@@ -64,10 +64,15 @@ class SaltedSeedSeq {
template <typename RandomAccessIterator>
void generate(RandomAccessIterator begin, RandomAccessIterator end) {
+ // The common case is that generate is called with ContiguousIterators
+ // to uint arrays. Such contiguous memory regions may be optimized,
+ // which we detect here.
+ using tag = absl::conditional_t<
+ (std::is_pointer<RandomAccessIterator>::value &&
+ std::is_same<absl::decay_t<decltype(*begin)>, uint32_t>::value),
+ ContiguousAndUint32Tag, DefaultTag>;
if (begin != end) {
- generate_impl(
- std::integral_constant<bool, sizeof(*begin) == sizeof(uint32_t)>{},
- begin, end);
+ generate_impl(begin, end, tag{});
}
}
@@ -79,19 +84,12 @@ class SaltedSeedSeq {
size_t size() const { return seq_->size(); }
private:
- // The common case for generate is that it is called with iterators over a
- // 32-bit value buffer. These can be reinterpreted to a uint32_t and we can
- // operate on them as such.
- template <typename RandomAccessIterator>
- void generate_impl(std::integral_constant<bool, true> /*is_32bit*/,
- RandomAccessIterator begin, RandomAccessIterator end) {
- seq_->generate(begin, end);
- const uint32_t salt = absl::random_internal::GetSaltMaterial().value_or(0);
- auto buffer = absl::MakeSpan(begin, end);
- MixIntoSeedMaterial(
- absl::MakeConstSpan(&salt, 1),
- absl::MakeSpan(reinterpret_cast<uint32_t*>(buffer.data()),
- buffer.size()));
+ struct ContiguousAndUint32Tag {};
+ struct DefaultTag {};
+
+ // Generate which requires the iterators are contiguous pointers to uint32_t.
+ void generate_impl(uint32_t* begin, uint32_t* end, ContiguousAndUint32Tag) {
+ generate_contiguous(absl::MakeSpan(begin, end));
}
// The uncommon case for generate is that it is called with iterators over
@@ -99,17 +97,32 @@ class SaltedSeedSeq {
// case we allocate a temporary 32-bit buffer and then copy-assign back
// to the initial inputs.
template <typename RandomAccessIterator>
- void generate_impl(std::integral_constant<bool, false> /*is_32bit*/,
- RandomAccessIterator begin, RandomAccessIterator end) {
- // Allocate a temporary buffer, seed, and then copy.
- absl::InlinedVector<uint32_t, 8> data(std::distance(begin, end), 0);
- generate_impl(std::integral_constant<bool, true>{}, data.begin(),
- data.end());
- std::copy(data.begin(), data.end(), begin);
+ void generate_impl(RandomAccessIterator begin, RandomAccessIterator end,
+ DefaultTag) {
+ return generate_and_copy(std::distance(begin, end), begin);
+ }
+
+ // Fills the initial seed buffer the underlying SSeq::generate() call,
+ // mixing in the salt material.
+ void generate_contiguous(absl::Span<uint32_t> buffer) {
+ seq_->generate(buffer.begin(), buffer.end());
+ const uint32_t salt = absl::random_internal::GetSaltMaterial().value_or(0);
+ MixIntoSeedMaterial(absl::MakeConstSpan(&salt, 1), buffer);
+ }
+
+ // Allocates a seed buffer of `n` elements, generates the seed, then
+ // copies the result into the `out` iterator.
+ template <typename Iterator>
+ void generate_and_copy(size_t n, Iterator out) {
+ // Allocate a temporary buffer, generate, and then copy.
+ absl::InlinedVector<uint32_t, 8> data(n, 0);
+ generate_contiguous(absl::MakeSpan(data.data(), data.size()));
+ std::copy(data.begin(), data.end(), out);
}
- // Because [rand.req.seedseq] is not copy-constructible, copy-assignable nor
- // movable so we wrap it with unique pointer to be able to move SaltedSeedSeq.
+ // Because [rand.req.seedseq] is not required to be copy-constructible,
+ // copy-assignable nor movable, we wrap it with unique pointer to be able
+ // to move SaltedSeedSeq.
std::unique_ptr<SSeq> seq_;
};
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 20:32:32 +0000