Export of internal Abseil changes

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2e894f3c2fadc789abf9011222526d5da1e0433e by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 267557172

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535be36d401a556156223ecc1aabd73a271f0f05 by Abseil Team <absl-team@google.com>:

Internal change.

PiperOrigin-RevId: 267456795
GitOrigin-RevId: 2e894f3c2fadc789abf9011222526d5da1e0433e
Change-Id: I95d29cbde5cd8342ae71b77728baa61b7cf6d440
This commit is contained in:
Abseil Team 2019-09-06 02:25:12 -07:00 committed by Gennadiy Rozental
parent 83c1d65c90
commit 325fd7b042
4 changed files with 23 additions and 30 deletions

View file

@ -261,13 +261,6 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
return true;
}
void CommandLineFlag::StoreAtomic(size_t size) {
int64_t t = 0;
assert(size <= sizeof(int64_t));
memcpy(&t, cur_, size);
atomic_.store(t, std::memory_order_release);
}
void CommandLineFlag::CheckDefaultValueParsingRoundtrip() const {
std::string v = DefaultValue();
@ -305,8 +298,6 @@ bool CommandLineFlag::ValidateInputValue(absl::string_view value) const {
return result;
}
const int64_t CommandLineFlag::kAtomicInit;
void CommandLineFlag::Read(void* dst,
const flags_internal::FlagOpFn dst_op) const {
absl::ReaderMutexLock l(InitFlagIfNecessary());
@ -369,7 +360,7 @@ std::string HelpText::GetHelpText() const {
void UpdateCopy(CommandLineFlag* flag) {
#define STORE_ATOMIC(T) \
else if (flag->IsOfType<T>()) { \
flag->StoreAtomic(sizeof(T)); \
flag->StoreAtomic(); \
}
if (false) {

View file

@ -207,7 +207,6 @@ class CommandLineFlag {
def_(def),
cur_(cur),
counter_(0),
atomic_(kAtomicInit),
locks_(nullptr) {}
// Virtual destructor
@ -235,6 +234,10 @@ class CommandLineFlag {
std::string DefaultValue() const;
std::string CurrentValue() const;
// Interface to store the value in atomic if one used. This is short term
// interface. To be reworked once cur_ is moved.
virtual void StoreAtomic() {}
// Interfaces to operate on validators.
virtual bool HasValidatorFn() const { return false; }
virtual bool InvokeValidator(const void* /*value*/) const { return true; }
@ -276,8 +279,6 @@ class CommandLineFlag {
flags_internal::FlagSettingMode set_mode,
flags_internal::ValueSource source, std::string* error);
void StoreAtomic(size_t size);
void CheckDefaultValueParsingRoundtrip() const;
// Constant configuration for a particular flag.
@ -300,11 +301,6 @@ class CommandLineFlag {
void* cur_; // Lazily initialized pointer to current value
int64_t counter_; // Mutation counter
// For some types, a copy of the current value is kept in an atomically
// accessible field.
static const int64_t kAtomicInit = 0xababababababababll;
std::atomic<int64_t> atomic_;
// Lazily initialized mutexes for this flag value. We cannot inline a
// SpinLock or Mutex here because those have non-constexpr constructors and
// so would prevent constant initialization of this type.

View file

@ -16,12 +16,16 @@
#ifndef ABSL_FLAGS_INTERNAL_FLAG_H_
#define ABSL_FLAGS_INTERNAL_FLAG_H_
#include <cstring>
#include "absl/flags/internal/commandlineflag.h"
#include "absl/flags/internal/registry.h"
namespace absl {
namespace flags_internal {
constexpr int64_t AtomicInit() { return 0xababababababababll; }
// Signature for the mutation callback used by watched Flags
// The callback is noexcept.
// TODO(rogeeff): add noexcept after C++17 support is added.
@ -44,6 +48,7 @@ class Flag final : public flags_internal::CommandLineFlag {
initial_value_gen,
/*def=*/nullptr,
/*cur=*/nullptr),
atomic_(flags_internal::AtomicInit()),
callback_(nullptr) {}
T Get() const {
@ -76,8 +81,8 @@ class Flag final : public flags_internal::CommandLineFlag {
bool AtomicGet(T* v) const {
const int64_t r = atomic_.load(std::memory_order_acquire);
if (r != flags_internal::CommandLineFlag::kAtomicInit) {
memcpy(v, &r, sizeof(T));
if (r != flags_internal::AtomicInit()) {
std::memcpy(v, &r, sizeof(T));
return true;
}
@ -108,7 +113,18 @@ class Flag final : public flags_internal::CommandLineFlag {
delete locks_;
}
void StoreAtomic() override {
if (sizeof(T) <= sizeof(int64_t)) {
int64_t t = 0;
std::memcpy(&t, cur_, (std::min)(sizeof(T), sizeof(int64_t)));
atomic_.store(t, std::memory_order_release);
}
}
// Flag's data
// For some types, a copy of the current value is kept in an atomically
// accessible field.
std::atomic<int64_t> atomic_;
FlagCallback callback_; // Mutation callback
};

View file

@ -34,16 +34,6 @@ config_setting(
### libraries
cc_library(
name = "includes",
textual_hdrs = [
"include/cctz/civil_time.h",
"include/cctz/civil_time_detail.h",
"include/cctz/time_zone.h",
],
visibility = ["//absl/time:__pkg__"],
)
cc_library(
name = "civil_time",
srcs = ["src/civil_time_detail.cc"],