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-rw-r--r--absl/container/BUILD.bazel20
-rw-r--r--absl/container/CMakeLists.txt1
-rw-r--r--absl/container/fixed_array.h154
-rw-r--r--absl/container/fixed_array_test.cc213
-rw-r--r--absl/container/internal/compressed_tuple.h175
-rw-r--r--absl/container/internal/compressed_tuple_test.cc166
-rw-r--r--absl/memory/memory.h56
-rw-r--r--absl/memory/memory_exception_safety_test.cc11
-rw-r--r--absl/memory/memory_test.cc43
-rw-r--r--absl/meta/type_traits.h44
-rw-r--r--absl/meta/type_traits_test.cc81
-rw-r--r--absl/strings/numbers_test.cc7
-rw-r--r--absl/time/duration.cc5
-rw-r--r--absl/time/duration_benchmark.cc78
-rw-r--r--absl/time/duration_test.cc124
-rw-r--r--absl/time/time.h97
-rw-r--r--absl/types/internal/variant.h28
17 files changed, 1066 insertions, 237 deletions
diff --git a/absl/container/BUILD.bazel b/absl/container/BUILD.bazel
index 07df3675..6d5c958f 100644
--- a/absl/container/BUILD.bazel
+++ b/absl/container/BUILD.bazel
@@ -26,10 +26,30 @@ package(default_visibility = ["//visibility:public"])
licenses(["notice"]) # Apache 2.0
cc_library(
+ name = "compressed_tuple",
+ hdrs = ["internal/compressed_tuple.h"],
+ copts = ABSL_DEFAULT_COPTS,
+ deps = [
+ "//absl/utility",
+ ],
+)
+
+cc_test(
+ name = "compressed_tuple_test",
+ srcs = ["internal/compressed_tuple_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ deps = [
+ ":compressed_tuple",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_library(
name = "fixed_array",
hdrs = ["fixed_array.h"],
copts = ABSL_DEFAULT_COPTS,
deps = [
+ ":compressed_tuple",
"//absl/algorithm",
"//absl/base:core_headers",
"//absl/base:dynamic_annotations",
diff --git a/absl/container/CMakeLists.txt b/absl/container/CMakeLists.txt
index d580b489..123e4c48 100644
--- a/absl/container/CMakeLists.txt
+++ b/absl/container/CMakeLists.txt
@@ -52,7 +52,6 @@ absl_library(
${TEST_INSTANCE_TRACKER_LIB_SRC}
PUBLIC_LIBRARIES
absl::container
- DISABLE_INSTALL
)
diff --git a/absl/container/fixed_array.h b/absl/container/fixed_array.h
index 62600df0..f480047a 100644
--- a/absl/container/fixed_array.h
+++ b/absl/container/fixed_array.h
@@ -47,6 +47,7 @@
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/base/port.h"
+#include "absl/container/internal/compressed_tuple.h"
#include "absl/memory/memory.h"
namespace absl {
@@ -76,73 +77,99 @@ constexpr static auto kFixedArrayUseDefault = static_cast<size_t>(-1);
// heap allocation, it will do so with global `::operator new[]()` and
// `::operator delete[]()`, even if T provides class-scope overrides for these
// operators.
-template <typename T, size_t inlined = kFixedArrayUseDefault>
+template <typename T, size_t N = kFixedArrayUseDefault,
+ typename A = std::allocator<T>>
class FixedArray {
static_assert(!std::is_array<T>::value || std::extent<T>::value > 0,
"Arrays with unknown bounds cannot be used with FixedArray.");
+
static constexpr size_t kInlineBytesDefault = 256;
+ using AllocatorTraits = std::allocator_traits<A>;
// std::iterator_traits isn't guaranteed to be SFINAE-friendly until C++17,
// but this seems to be mostly pedantic.
template <typename Iterator>
using EnableIfForwardIterator = absl::enable_if_t<std::is_convertible<
typename std::iterator_traits<Iterator>::iterator_category,
std::forward_iterator_tag>::value>;
+ static constexpr bool NoexceptCopyable() {
+ return std::is_nothrow_copy_constructible<StorageElement>::value &&
+ absl::allocator_is_nothrow<allocator_type>::value;
+ }
+ static constexpr bool NoexceptMovable() {
+ return std::is_nothrow_move_constructible<StorageElement>::value &&
+ absl::allocator_is_nothrow<allocator_type>::value;
+ }
+ static constexpr bool DefaultConstructorIsNonTrivial() {
+ return !absl::is_trivially_default_constructible<StorageElement>::value;
+ }
public:
- using value_type = T;
- using iterator = T*;
- using const_iterator = const T*;
+ using allocator_type = typename AllocatorTraits::allocator_type;
+ using value_type = typename allocator_type::value_type;
+ using pointer = typename allocator_type::pointer;
+ using const_pointer = typename allocator_type::const_pointer;
+ using reference = typename allocator_type::reference;
+ using const_reference = typename allocator_type::const_reference;
+ using size_type = typename allocator_type::size_type;
+ using difference_type = typename allocator_type::difference_type;
+ using iterator = pointer;
+ using const_iterator = const_pointer;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
- using reference = T&;
- using const_reference = const T&;
- using pointer = T*;
- using const_pointer = const T*;
- using difference_type = ptrdiff_t;
- using size_type = size_t;
static constexpr size_type inline_elements =
- inlined == kFixedArrayUseDefault
- ? kInlineBytesDefault / sizeof(value_type)
- : inlined;
+ (N == kFixedArrayUseDefault ? kInlineBytesDefault / sizeof(value_type)
+ : static_cast<size_type>(N));
- FixedArray(const FixedArray& other)
- : FixedArray(other.begin(), other.end()) {}
+ FixedArray(
+ const FixedArray& other,
+ const allocator_type& a = allocator_type()) noexcept(NoexceptCopyable())
+ : FixedArray(other.begin(), other.end(), a) {}
- FixedArray(FixedArray&& other) noexcept(
- absl::conjunction<absl::allocator_is_nothrow<std::allocator<value_type>>,
- std::is_nothrow_move_constructible<value_type>>::value)
+ FixedArray(
+ FixedArray&& other,
+ const allocator_type& a = allocator_type()) noexcept(NoexceptMovable())
: FixedArray(std::make_move_iterator(other.begin()),
- std::make_move_iterator(other.end())) {}
+ std::make_move_iterator(other.end()), a) {}
// Creates an array object that can store `n` elements.
// Note that trivially constructible elements will be uninitialized.
- explicit FixedArray(size_type n) : storage_(n) {
- absl::memory_internal::uninitialized_default_construct_n(storage_.begin(),
- size());
+ explicit FixedArray(size_type n, const allocator_type& a = allocator_type())
+ : storage_(n, a) {
+ if (DefaultConstructorIsNonTrivial()) {
+ memory_internal::ConstructStorage(storage_.alloc(), storage_.begin(),
+ storage_.end());
+ }
}
// Creates an array initialized with `n` copies of `val`.
- FixedArray(size_type n, const value_type& val) : storage_(n) {
- std::uninitialized_fill_n(data(), size(), val);
+ FixedArray(size_type n, const value_type& val,
+ const allocator_type& a = allocator_type())
+ : storage_(n, a) {
+ memory_internal::ConstructStorage(storage_.alloc(), storage_.begin(),
+ storage_.end(), val);
}
+ // Creates an array initialized with the size and contents of `init_list`.
+ FixedArray(std::initializer_list<value_type> init_list,
+ const allocator_type& a = allocator_type())
+ : FixedArray(init_list.begin(), init_list.end(), a) {}
+
// Creates an array initialized with the elements from the input
// range. The array's size will always be `std::distance(first, last)`.
// REQUIRES: Iterator must be a forward_iterator or better.
template <typename Iterator, EnableIfForwardIterator<Iterator>* = nullptr>
- FixedArray(Iterator first, Iterator last)
- : storage_(std::distance(first, last)) {
- std::uninitialized_copy(first, last, data());
+ FixedArray(Iterator first, Iterator last,
+ const allocator_type& a = allocator_type())
+ : storage_(std::distance(first, last), a) {
+ memory_internal::CopyToStorageFromRange(storage_.alloc(), storage_.begin(),
+ first, last);
}
- FixedArray(std::initializer_list<value_type> init_list)
- : FixedArray(init_list.begin(), init_list.end()) {}
-
~FixedArray() noexcept {
- for (const StorageElement& cur : storage_) {
- cur.~StorageElement();
+ for (auto* cur = storage_.begin(); cur != storage_.end(); ++cur) {
+ AllocatorTraits::destroy(*storage_.alloc(), cur);
}
}
@@ -332,7 +359,6 @@ class FixedArray {
friend bool operator>=(const FixedArray& lhs, const FixedArray& rhs) {
return !(lhs < rhs);
}
-
private:
// StorageElement
//
@@ -364,6 +390,8 @@ class FixedArray {
using StorageElement =
absl::conditional_t<std::is_array<value_type>::value,
StorageElementWrapper<value_type>, value_type>;
+ using StorageElementBuffer =
+ absl::aligned_storage_t<sizeof(StorageElement), alignof(StorageElement)>;
static pointer AsValueType(pointer ptr) { return ptr; }
static pointer AsValueType(StorageElementWrapper<value_type>* ptr) {
@@ -374,9 +402,6 @@ class FixedArray {
static_assert(alignof(StorageElement) == alignof(value_type), "");
struct NonEmptyInlinedStorage {
- using StorageElementBuffer =
- absl::aligned_storage_t<sizeof(StorageElement),
- alignof(StorageElement)>;
StorageElement* data() {
return reinterpret_cast<StorageElement*>(inlined_storage_.data());
}
@@ -386,8 +411,8 @@ class FixedArray {
void* RedzoneEnd() { return &redzone_end_ + 1; }
#endif // ADDRESS_SANITIZER
- void AnnotateConstruct(size_t);
- void AnnotateDestruct(size_t);
+ void AnnotateConstruct(size_type);
+ void AnnotateDestruct(size_type);
ADDRESS_SANITIZER_REDZONE(redzone_begin_);
std::array<StorageElementBuffer, inline_elements> inlined_storage_;
@@ -396,8 +421,8 @@ class FixedArray {
struct EmptyInlinedStorage {
StorageElement* data() { return nullptr; }
- void AnnotateConstruct(size_t) {}
- void AnnotateDestruct(size_t) {}
+ void AnnotateConstruct(size_type) {}
+ void AnnotateDestruct(size_type) {}
};
using InlinedStorage =
@@ -414,48 +439,57 @@ class FixedArray {
//
class Storage : public InlinedStorage {
public:
- explicit Storage(size_type n) : data_(CreateStorage(n)), size_(n) {}
+ Storage(size_type n, const allocator_type& a)
+ : size_alloc_(n, a), data_(InitializeData()) {}
+
~Storage() noexcept {
if (UsingInlinedStorage(size())) {
- this->AnnotateDestruct(size());
+ InlinedStorage::AnnotateDestruct(size());
} else {
- std::allocator<StorageElement>().deallocate(begin(), size());
+ AllocatorTraits::deallocate(*alloc(), AsValueType(begin()), size());
}
}
- size_type size() const { return size_; }
+ size_type size() const { return size_alloc_.template get<0>(); }
StorageElement* begin() const { return data_; }
StorageElement* end() const { return begin() + size(); }
+ allocator_type* alloc() {
+ return std::addressof(size_alloc_.template get<1>());
+ }
private:
static bool UsingInlinedStorage(size_type n) {
return n <= inline_elements;
}
- StorageElement* CreateStorage(size_type n) {
- if (UsingInlinedStorage(n)) {
- this->AnnotateConstruct(n);
+ StorageElement* InitializeData() {
+ if (UsingInlinedStorage(size())) {
+ InlinedStorage::AnnotateConstruct(size());
return InlinedStorage::data();
} else {
- return std::allocator<StorageElement>().allocate(n);
+ return reinterpret_cast<StorageElement*>(
+ AllocatorTraits::allocate(*alloc(), size()));
}
}
- StorageElement* const data_;
- const size_type size_;
+ // `CompressedTuple` takes advantage of EBCO for stateless `allocator_type`s
+ container_internal::CompressedTuple<size_type, allocator_type> size_alloc_;
+ StorageElement* data_;
};
- const Storage storage_;
+ Storage storage_;
};
-template <typename T, size_t N>
-constexpr size_t FixedArray<T, N>::inline_elements;
+template <typename T, size_t N, typename A>
+constexpr size_t FixedArray<T, N, A>::kInlineBytesDefault;
-template <typename T, size_t N>
-constexpr size_t FixedArray<T, N>::kInlineBytesDefault;
+template <typename T, size_t N, typename A>
+constexpr typename FixedArray<T, N, A>::size_type
+ FixedArray<T, N, A>::inline_elements;
-template <typename T, size_t N>
-void FixedArray<T, N>::NonEmptyInlinedStorage::AnnotateConstruct(size_t n) {
+template <typename T, size_t N, typename A>
+void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateConstruct(
+ typename FixedArray<T, N, A>::size_type n) {
#ifdef ADDRESS_SANITIZER
if (!n) return;
ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), RedzoneEnd(), data() + n);
@@ -464,8 +498,9 @@ void FixedArray<T, N>::NonEmptyInlinedStorage::AnnotateConstruct(size_t n) {
static_cast<void>(n); // Mark used when not in asan mode
}
-template <typename T, size_t N>
-void FixedArray<T, N>::NonEmptyInlinedStorage::AnnotateDestruct(size_t n) {
+template <typename T, size_t N, typename A>
+void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateDestruct(
+ typename FixedArray<T, N, A>::size_type n) {
#ifdef ADDRESS_SANITIZER
if (!n) return;
ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), data() + n, RedzoneEnd());
@@ -473,6 +508,5 @@ void FixedArray<T, N>::NonEmptyInlinedStorage::AnnotateDestruct(size_t n) {
#endif // ADDRESS_SANITIZER
static_cast<void>(n); // Mark used when not in asan mode
}
-
} // namespace absl
#endif // ABSL_CONTAINER_FIXED_ARRAY_H_
diff --git a/absl/container/fixed_array_test.cc b/absl/container/fixed_array_test.cc
index 2142132d..b07ebcb6 100644
--- a/absl/container/fixed_array_test.cc
+++ b/absl/container/fixed_array_test.cc
@@ -15,9 +15,11 @@
#include "absl/container/fixed_array.h"
#include <stdio.h>
+#include <cstring>
#include <list>
#include <memory>
#include <numeric>
+#include <scoped_allocator>
#include <stdexcept>
#include <string>
#include <vector>
@@ -607,6 +609,216 @@ TEST(FixedArrayTest, Fill) {
empty.fill(fill_val);
}
+// TODO(johnsoncj): Investigate InlinedStorage default initialization in GCC 4.x
+#ifndef __GNUC__
+TEST(FixedArrayTest, DefaultCtorDoesNotValueInit) {
+ using T = char;
+ constexpr auto capacity = 10;
+ using FixedArrType = absl::FixedArray<T, capacity>;
+ using FixedArrBuffType =
+ absl::aligned_storage_t<sizeof(FixedArrType), alignof(FixedArrType)>;
+ constexpr auto scrubbed_bits = 0x95;
+ constexpr auto length = capacity / 2;
+
+ FixedArrBuffType buff;
+ std::memset(std::addressof(buff), scrubbed_bits, sizeof(FixedArrBuffType));
+
+ FixedArrType* arr =
+ ::new (static_cast<void*>(std::addressof(buff))) FixedArrType(length);
+ EXPECT_THAT(*arr, testing::Each(scrubbed_bits));
+ arr->~FixedArrType();
+}
+#endif // __GNUC__
+
+// This is a stateful allocator, but the state lives outside of the
+// allocator (in whatever test is using the allocator). This is odd
+// but helps in tests where the allocator is propagated into nested
+// containers - that chain of allocators uses the same state and is
+// thus easier to query for aggregate allocation information.
+template <typename T>
+class CountingAllocator : public std::allocator<T> {
+ public:
+ using Alloc = std::allocator<T>;
+ using pointer = typename Alloc::pointer;
+ using size_type = typename Alloc::size_type;
+
+ CountingAllocator() : bytes_used_(nullptr), instance_count_(nullptr) {}
+ explicit CountingAllocator(int64_t* b)
+ : bytes_used_(b), instance_count_(nullptr) {}
+ CountingAllocator(int64_t* b, int64_t* a)
+ : bytes_used_(b), instance_count_(a) {}
+
+ template <typename U>
+ explicit CountingAllocator(const CountingAllocator<U>& x)
+ : Alloc(x),
+ bytes_used_(x.bytes_used_),
+ instance_count_(x.instance_count_) {}
+
+ pointer allocate(size_type n, const void* const hint = nullptr) {
+ assert(bytes_used_ != nullptr);
+ *bytes_used_ += n * sizeof(T);
+ return Alloc::allocate(n, hint);
+ }
+
+ void deallocate(pointer p, size_type n) {
+ Alloc::deallocate(p, n);
+ assert(bytes_used_ != nullptr);
+ *bytes_used_ -= n * sizeof(T);
+ }
+
+ template <typename... Args>
+ void construct(pointer p, Args&&... args) {
+ Alloc::construct(p, absl::forward<Args>(args)...);
+ if (instance_count_) {
+ *instance_count_ += 1;
+ }
+ }
+
+ void destroy(pointer p) {
+ Alloc::destroy(p);
+ if (instance_count_) {
+ *instance_count_ -= 1;
+ }
+ }
+
+ template <typename U>
+ class rebind {
+ public:
+ using other = CountingAllocator<U>;
+ };
+
+ int64_t* bytes_used_;
+ int64_t* instance_count_;
+};
+
+TEST(AllocatorSupportTest, CountInlineAllocations) {
+ constexpr size_t inlined_size = 4;
+ using Alloc = CountingAllocator<int>;
+ using AllocFxdArr = absl::FixedArray<int, inlined_size, Alloc>;
+
+ int64_t allocated = 0;
+ int64_t active_instances = 0;
+
+ {
+ const int ia[] = {0, 1, 2, 3, 4, 5, 6, 7};
+
+ Alloc alloc(&allocated, &active_instances);
+
+ AllocFxdArr arr(ia, ia + inlined_size, alloc);
+ static_cast<void>(arr);
+ }
+
+ EXPECT_EQ(allocated, 0);
+ EXPECT_EQ(active_instances, 0);
+}
+
+TEST(AllocatorSupportTest, CountOutoflineAllocations) {
+ constexpr size_t inlined_size = 4;
+ using Alloc = CountingAllocator<int>;
+ using AllocFxdArr = absl::FixedArray<int, inlined_size, Alloc>;
+
+ int64_t allocated = 0;
+ int64_t active_instances = 0;
+
+ {
+ const int ia[] = {0, 1, 2, 3, 4, 5, 6, 7};
+ Alloc alloc(&allocated, &active_instances);
+
+ AllocFxdArr arr(ia, ia + ABSL_ARRAYSIZE(ia), alloc);
+
+ EXPECT_EQ(allocated, arr.size() * sizeof(int));
+ static_cast<void>(arr);
+ }
+
+ EXPECT_EQ(active_instances, 0);
+}
+
+TEST(AllocatorSupportTest, CountCopyInlineAllocations) {
+ constexpr size_t inlined_size = 4;
+ using Alloc = CountingAllocator<int>;
+ using AllocFxdArr = absl::FixedArray<int, inlined_size, Alloc>;
+
+ int64_t allocated1 = 0;
+ int64_t allocated2 = 0;
+ int64_t active_instances = 0;
+ Alloc alloc(&allocated1, &active_instances);
+ Alloc alloc2(&allocated2, &active_instances);
+
+ {
+ int initial_value = 1;
+
+ AllocFxdArr arr1(inlined_size / 2, initial_value, alloc);
+
+ EXPECT_EQ(allocated1, 0);
+
+ AllocFxdArr arr2(arr1, alloc2);
+
+ EXPECT_EQ(allocated2, 0);
+ static_cast<void>(arr1);
+ static_cast<void>(arr2);
+ }
+
+ EXPECT_EQ(active_instances, 0);
+}
+
+TEST(AllocatorSupportTest, CountCopyOutoflineAllocations) {
+ constexpr size_t inlined_size = 4;
+ using Alloc = CountingAllocator<int>;
+ using AllocFxdArr = absl::FixedArray<int, inlined_size, Alloc>;
+
+ int64_t allocated1 = 0;
+ int64_t allocated2 = 0;
+ int64_t active_instances = 0;
+ Alloc alloc(&allocated1, &active_instances);
+ Alloc alloc2(&allocated2, &active_instances);
+
+ {
+ int initial_value = 1;
+
+ AllocFxdArr arr1(inlined_size * 2, initial_value, alloc);
+
+ EXPECT_EQ(allocated1, arr1.size() * sizeof(int));
+
+ AllocFxdArr arr2(arr1, alloc2);
+
+ EXPECT_EQ(allocated2, inlined_size * 2 * sizeof(int));
+ static_cast<void>(arr1);
+ static_cast<void>(arr2);
+ }
+
+ EXPECT_EQ(active_instances, 0);
+}
+
+TEST(AllocatorSupportTest, SizeValAllocConstructor) {
+ using testing::AllOf;
+ using testing::Each;
+ using testing::SizeIs;
+
+ constexpr size_t inlined_size = 4;
+ using Alloc = CountingAllocator<int>;
+ using AllocFxdArr = absl::FixedArray<int, inlined_size, Alloc>;
+
+ {
+ auto len = inlined_size / 2;
+ auto val = 0;
+ int64_t allocated = 0;
+ AllocFxdArr arr(len, val, Alloc(&allocated));
+
+ EXPECT_EQ(allocated, 0);
+ EXPECT_THAT(arr, AllOf(SizeIs(len), Each(0)));
+ }
+
+ {
+ auto len = inlined_size * 2;
+ auto val = 0;
+ int64_t allocated = 0;
+ AllocFxdArr arr(len, val, Alloc(&allocated));
+
+ EXPECT_EQ(allocated, len * sizeof(int));
+ EXPECT_THAT(arr, AllOf(SizeIs(len), Each(0)));
+ }
+}
+
#ifdef ADDRESS_SANITIZER
TEST(FixedArrayTest, AddressSanitizerAnnotations1) {
absl::FixedArray<int, 32> a(10);
@@ -655,5 +867,4 @@ TEST(FixedArrayTest, AddressSanitizerAnnotations4) {
EXPECT_DEATH(raw[21] = ThreeInts(), "container-overflow");
}
#endif // ADDRESS_SANITIZER
-
} // namespace
diff --git a/absl/container/internal/compressed_tuple.h b/absl/container/internal/compressed_tuple.h
new file mode 100644
index 00000000..cc52614f
--- /dev/null
+++ b/absl/container/internal/compressed_tuple.h
@@ -0,0 +1,175 @@
+// Copyright 2018 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
+//
+// 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.
+//
+// Helper class to perform the Empty Base Optimization.
+// Ts can contain classes and non-classes, empty or not. For the ones that
+// are empty classes, we perform the optimization. If all types in Ts are empty
+// classes, then CompressedTuple<Ts...> is itself an empty class.
+//
+// To access the members, use member get<N>() function.
+//
+// Eg:
+// absl::container_internal::CompressedTuple<int, T1, T2, T3> value(7, t1, t2,
+// t3);
+// assert(value.get<0>() == 7);
+// T1& t1 = value.get<1>();
+// const T2& t2 = value.get<2>();
+// ...
+//
+// http://en.cppreference.com/w/cpp/language/ebo
+
+#ifndef ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_
+#define ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_
+
+#include <tuple>
+#include <type_traits>
+#include <utility>
+
+#include "absl/utility/utility.h"
+
+#ifdef _MSC_VER
+// We need to mark these classes with this declspec to ensure that
+// CompressedTuple happens.
+#define ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC __declspec(empty_bases)
+#else // _MSC_VER
+#define ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
+#endif // _MSC_VER
+
+namespace absl {
+namespace container_internal {
+
+template <typename... Ts>
+class CompressedTuple;
+
+namespace internal_compressed_tuple {
+
+template <typename D, size_t I>
+struct Elem;
+template <typename... B, size_t I>
+struct Elem<CompressedTuple<B...>, I>
+ : std::tuple_element<I, std::tuple<B...>> {};
+template <typename D, size_t I>
+using ElemT = typename Elem<D, I>::type;
+
+// Use the __is_final intrinsic if available. Where it's not available, classes
+// declared with the 'final' specifier cannot be used as CompressedTuple
+// elements.
+// TODO(sbenza): Replace this with std::is_final in C++14.
+template <typename T>
+constexpr bool IsFinal() {
+#if defined(__clang__) || defined(__GNUC__)
+ return __is_final(T);
+#else
+ return false;
+#endif
+}
+
+template <typename T>
+constexpr bool ShouldUseBase() {
+ return std::is_class<T>::value && std::is_empty<T>::value && !IsFinal<T>();
+}
+
+// The storage class provides two specializations:
+// - For empty classes, it stores T as a base class.
+// - For everything else, it stores T as a member.
+template <typename D, size_t I, bool = ShouldUseBase<ElemT<D, I>>()>
+struct Storage {
+ using T = ElemT<D, I>;
+ T value;
+ constexpr Storage() = default;
+ explicit constexpr Storage(T&& v) : value(absl::forward<T>(v)) {}
+ constexpr const T& get() const { return value; }
+ T& get() { return value; }
+};
+
+template <typename D, size_t I>
+struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC Storage<D, I, true>
+ : ElemT<D, I> {
+ using T = internal_compressed_tuple::ElemT<D, I>;
+ constexpr Storage() = default;
+ explicit constexpr Storage(T&& v) : T(absl::forward<T>(v)) {}
+ constexpr const T& get() const { return *this; }
+ T& get() { return *this; }
+};
+
+template <typename D, typename I>
+struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl;
+
+template <typename... Ts, size_t... I>
+struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
+ CompressedTupleImpl<CompressedTuple<Ts...>, absl::index_sequence<I...>>
+ // We use the dummy identity function through std::integral_constant to
+ // convince MSVC of accepting and expanding I in that context. Without it
+ // you would get:
+ // error C3548: 'I': parameter pack cannot be used in this context
+ : Storage<CompressedTuple<Ts...>,
+ std::integral_constant<size_t, I>::value>... {
+ constexpr CompressedTupleImpl() = default;
+ explicit constexpr CompressedTupleImpl(Ts&&... args)
+ : Storage<CompressedTuple<Ts...>, I>(absl::forward<Ts>(args))... {}
+};
+
+} // namespace internal_compressed_tuple
+
+// Helper class to perform the Empty Base Class Optimization.
+// Ts can contain classes and non-classes, empty or not. For the ones that
+// are empty classes, we perform the CompressedTuple. If all types in Ts are
+// empty classes, then CompressedTuple<Ts...> is itself an empty class.
+//
+// To access the members, use member .get<N>() function.
+//
+// Eg:
+// absl::container_internal::CompressedTuple<int, T1, T2, T3> value(7, t1, t2,
+// t3);
+// assert(value.get<0>() == 7);
+// T1& t1 = value.get<1>();
+// const T2& t2 = value.get<2>();
+// ...
+//
+// http://en.cppreference.com/w/cpp/language/ebo
+template <typename... Ts>
+class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple
+ : private internal_compressed_tuple::CompressedTupleImpl<
+ CompressedTuple<Ts...>, absl::index_sequence_for<Ts...>> {
+ private:
+ template <int I>
+ using ElemT = internal_compressed_tuple::ElemT<CompressedTuple, I>;
+
+ public:
+ constexpr CompressedTuple() = default;
+ explicit constexpr CompressedTuple(Ts... base)
+ : CompressedTuple::CompressedTupleImpl(absl::forward<Ts>(base)...) {}
+
+ template <int I>
+ ElemT<I>& get() {
+ return internal_compressed_tuple::Storage<CompressedTuple, I>::get();
+ }
+
+ template <int I>
+ constexpr const ElemT<I>& get() const {
+ return internal_compressed_tuple::Storage<CompressedTuple, I>::get();
+ }
+};
+
+// Explicit specialization for a zero-element tuple
+// (needed to avoid ambiguous overloads for the default constructor).
+template <>
+class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple<> {};
+
+} // namespace container_internal
+} // namespace absl
+
+#undef ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
+
+#endif // ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_
diff --git a/absl/container/internal/compressed_tuple_test.cc b/absl/container/internal/compressed_tuple_test.cc
new file mode 100644
index 00000000..45030c67
--- /dev/null
+++ b/absl/container/internal/compressed_tuple_test.cc
@@ -0,0 +1,166 @@
+// Copyright 2018 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
+//
+// 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.
+
+#include "absl/container/internal/compressed_tuple.h"
+
+#include <string>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace absl {
+namespace container_internal {
+namespace {
+
+template <int>
+struct Empty {};
+
+template <typename T>
+struct NotEmpty {
+ T value;
+};
+
+template <typename T, typename U>
+struct TwoValues {
+ T value1;
+ U value2;
+};
+
+TEST(CompressedTupleTest, Sizeof) {
+ EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int>));
+ EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int, Empty<0>>));
+ EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int, Empty<0>, Empty<1>>));
+ EXPECT_EQ(sizeof(int),
+ sizeof(CompressedTuple<int, Empty<0>, Empty<1>, Empty<2>>));
+
+ EXPECT_EQ(sizeof(TwoValues<int, double>),
+ sizeof(CompressedTuple<int, NotEmpty<double>>));
+ EXPECT_EQ(sizeof(TwoValues<int, double>),
+ sizeof(CompressedTuple<int, Empty<0>, NotEmpty<double>>));
+ EXPECT_EQ(sizeof(TwoValues<int, double>),
+ sizeof(CompressedTuple<int, Empty<0>, NotEmpty<double>, Empty<1>>));
+}
+
+TEST(CompressedTupleTest, Access) {
+ struct S {
+ std::string x;
+ };
+ CompressedTuple<int, Empty<0>, S> x(7, {}, S{"ABC"});
+ EXPECT_EQ(sizeof(x), sizeof(TwoValues<int, S>));
+ EXPECT_EQ(7, x.get<0>());
+ EXPECT_EQ("ABC", x.get<2>().x);
+}
+
+TEST(CompressedTupleTest, NonClasses) {
+ CompressedTuple<int, const char*> x(7, "ABC");
+ EXPECT_EQ(7, x.get<0>());
+ EXPECT_STREQ("ABC", x.get<1>());
+}
+
+TEST(CompressedTupleTest, MixClassAndNonClass) {
+ CompressedTuple<int, const char*, Empty<0>, NotEmpty<double>> x(7, "ABC", {},
+ {1.25});
+ struct Mock {
+ int v;
+ const char* p;
+ double d;
+ };
+ EXPECT_EQ(sizeof(x), sizeof(Mock));
+ EXPECT_EQ(7, x.get<0>());
+ EXPECT_STREQ("ABC", x.get<1>());
+ EXPECT_EQ(1.25, x.get<3>().value);
+}
+
+TEST(CompressedTupleTest, Nested) {
+ CompressedTuple<int, CompressedTuple<int>,
+ CompressedTuple<int, CompressedTuple<int>>>
+ x(1, CompressedTuple<int>(2),
+ CompressedTuple<int, CompressedTuple<int>>(3, CompressedTuple<int>(4)));
+ EXPECT_EQ(1, x.get<0>());
+ EXPECT_EQ(2, x.get<1>().get<0>());
+ EXPECT_EQ(3, x.get<2>().get<0>());
+ EXPECT_EQ(4, x.get<2>().get<1>().get<0>());
+
+ CompressedTuple<Empty<0>, Empty<0>,
+ CompressedTuple<Empty<0>, CompressedTuple<Empty<0>>>>
+ y;
+ std::set<Empty<0>*> empties{&y.get<0>(), &y.get<1>(), &y.get<2>().get<0>(),
+ &y.get<2>().get<1>().get<0>()};
+#ifdef _MSC_VER
+ // MSVC has a bug where many instances of the same base class are layed out in
+ // the same address when using __declspec(empty_bases).
+ // This will be fixed in a future version of MSVC.
+ int expected = 1;
+#else
+ int expected = 4;
+#endif
+ EXPECT_EQ(expected, sizeof(y));
+ EXPECT_EQ(expected, empties.size());
+ EXPECT_EQ(sizeof(y), sizeof(Empty<0>) * empties.size());
+
+ EXPECT_EQ(4 * sizeof(char),
+ sizeof(CompressedTuple<CompressedTuple<char, char>,
+ CompressedTuple<char, char>>));
+ EXPECT_TRUE(
+ (std::is_empty<CompressedTuple<CompressedTuple<Empty<0>>,
+ CompressedTuple<Empty<1>>>>::value));
+}
+
+TEST(CompressedTupleTest, Reference) {
+ int i = 7;
+ std::string s = "Very long std::string that goes in the heap";
+ CompressedTuple<int, int&, std::string, std::string&> x(i, i, s, s);
+
+ // Sanity check. We should have not moved from `s`
+ EXPECT_EQ(s, "Very long std::string that goes in the heap");
+
+ EXPECT_EQ(x.get<0>(), x.get<1>());
+ EXPECT_NE(&x.get<0>(), &x.get<1>());
+ EXPECT_EQ(&x.get<1>(), &i);
+
+ EXPECT_EQ(x.get<2>(), x.get<3>());
+ EXPECT_NE(&x.get<2>(), &x.get<3>());
+ EXPECT_EQ(&x.get<3>(), &s);
+}
+
+TEST(CompressedTupleTest, NoElements) {
+ CompressedTuple<> x;
+ static_cast<void>(x); // Silence -Wunused-variable.
+ EXPECT_TRUE(std::is_empty<CompressedTuple<>>::value);
+}
+
+TEST(CompressedTupleTest, Constexpr) {
+ constexpr CompressedTuple<int, double, CompressedTuple<int>> x(
+ 7, 1.25, CompressedTuple<int>(5));
+ constexpr int x0 = x.get<0>();
+ constexpr double x1 = x.get<1>();
+ constexpr int x2 = x.get<2>().get<0>();
+ EXPECT_EQ(x0, 7);
+ EXPECT_EQ(x1, 1.25);
+ EXPECT_EQ(x2, 5);
+}
+
+#if defined(__clang__) || defined(__GNUC__)
+TEST(CompressedTupleTest, EmptyFinalClass) {
+ struct S final {
+ int f() const { return 5; }
+ };
+ CompressedTuple<S> x;
+ EXPECT_EQ(x.get<0>().f(), 5);
+}
+#endif
+
+} // namespace
+} // namespace container_internal
+} // namespace absl
diff --git a/absl/memory/memory.h b/absl/memory/memory.h
index f207169a..c7caf8b9 100644
--- a/absl/memory/memory.h
+++ b/absl/memory/memory.h
@@ -641,38 +641,56 @@ struct default_allocator_is_nothrow : std::false_type {};
#endif
namespace memory_internal {
-// TODO(b110200014): Implement proper backports
-template <typename ForwardIt>
-void DefaultConstruct(ForwardIt it) {
- using value_type = typename std::iterator_traits<ForwardIt>::value_type;
- ::new (static_cast<void*>(std::addressof(*it))) value_type;
-} // namespace memory_internal
-
#ifdef ABSL_HAVE_EXCEPTIONS
-template <typename ForwardIt, typename Size>
-void uninitialized_default_construct_n(ForwardIt first, Size size) {
- for (ForwardIt cur = first; size > 0; static_cast<void>(++cur), --size) {
+template <typename Allocator, typename StorageElement, typename... Args>
+void ConstructStorage(Allocator* alloc, StorageElement* first,
+ StorageElement* last, const Args&... args) {
+ for (StorageElement* cur = first; cur != last; ++cur) {
+ try {
+ std::allocator_traits<Allocator>::construct(*alloc, cur, args...);
+ } catch (...) {
+ while (cur != first) {
+ --cur;
+ std::allocator_traits<Allocator>::destroy(*alloc, cur);
+ }
+ throw;
+ }
+ }
+}
+template <typename Allocator, typename StorageElement, typename Iterator>
+void CopyToStorageFromRange(Allocator* alloc, StorageElement* destination,
+ Iterator first, Iterator last) {
+ for (StorageElement* cur = destination; first != last;
+ static_cast<void>(++cur), static_cast<void>(++first)) {
try {
- absl::memory_internal::DefaultConstruct(cur);
+ std::allocator_traits<Allocator>::construct(*alloc, cur, *first);
} catch (...) {
- using value_type = typename std::iterator_traits<ForwardIt>::value_type;
- for (; first != cur; ++first) {
- first->~value_type();
+ while (cur != destination) {
+ --cur;
+ std::allocator_traits<Allocator>::destroy(*alloc, cur);
}
throw;
}
}
}
#else // ABSL_HAVE_EXCEPTIONS
-template <typename ForwardIt, typename Size>
-void uninitialized_default_construct_n(ForwardIt first, Size size) {
- for (; size > 0; static_cast<void>(++first), --size) {
- absl::memory_internal::DefaultConstruct(first);
+template <typename Allocator, typename StorageElement, typename... Args>
+void ConstructStorage(Allocator* alloc, StorageElement* first,
+ StorageElement* last, const Args&... args) {
+ for (; first != last; ++first) {
+ std::allocator_traits<Allocator>::construct(*alloc, first, args...);
+ }
+}
+template <typename Allocator, typename StorageElement, typename Iterator>
+void CopyToStorageFromRange(Allocator* alloc, StorageElement* destination,
+ Iterator first, Iterator last) {
+ for (; first != last;
+ static_cast<void>(++destination), static_cast<void>(++first)) {
+ std::allocator_traits<Allocator>::construct(*alloc, destination, *first);
}
}
#endif // ABSL_HAVE_EXCEPTIONS
} // namespace memory_internal
-
} // namespace absl
#endif // ABSL_MEMORY_MEMORY_H_
diff --git a/absl/memory/memory_exception_safety_test.cc b/absl/memory/memory_exception_safety_test.cc
index fb8b561d..d1f6e84f 100644
--- a/absl/memory/memory_exception_safety_test.cc
+++ b/absl/memory/memory_exception_safety_test.cc
@@ -48,16 +48,5 @@ TEST(MakeUnique, CheckForLeaks) {
}));
}
-TEST(MemoryInternal, UninitDefaultConstructNNonTrivial) {
- EXPECT_TRUE(testing::MakeExceptionSafetyTester()
- .WithInitialValue(ThrowerList{})
- .WithOperation([&](ThrowerList* list_ptr) {
- absl::memory_internal::uninitialized_default_construct_n(
- list_ptr->data(), kLength);
- })
- .WithInvariants([&](...) { return true; })
- .Test());
-}
-
} // namespace
} // namespace absl
diff --git a/absl/memory/memory_test.cc b/absl/memory/memory_test.cc
index 8ff1945d..dee9b486 100644
--- a/absl/memory/memory_test.cc
+++ b/absl/memory/memory_test.cc
@@ -611,47 +611,4 @@ TEST(AllocatorNoThrowTest, CustomAllocator) {
EXPECT_FALSE(absl::allocator_is_nothrow<UnspecifiedAllocator>::value);
}
-TEST(MemoryInternal, UninitDefaultConstructNTrivial) {
- constexpr int kInitialValue = 123;
- constexpr int kExpectedValue = kInitialValue; // Expect no-op behavior
- constexpr int len = 5;
-
- struct TestObj {
- int val;
- };
- static_assert(absl::is_trivially_default_constructible<TestObj>::value, "");
- static_assert(absl::is_trivially_destructible<TestObj>::value, "");
-
- TestObj objs[len];
- for (auto& obj : objs) {
- obj.val = kInitialValue;
- }
-
- absl::memory_internal::uninitialized_default_construct_n(objs, len);
- for (auto& obj : objs) {
- EXPECT_EQ(obj.val, kExpectedValue);
- }
-}
-
-TEST(MemoryInternal, UninitDefaultConstructNNonTrivial) {
- constexpr int kInitialValue = 123;
- constexpr int kExpectedValue = 0; // Expect value-construction behavior
- constexpr int len = 5;
-
- struct TestObj {
- int val{kExpectedValue};
- };
- static_assert(absl::is_trivially_destructible<TestObj>::value, "");
-
- TestObj objs[len];
- for (auto& obj : objs) {
- obj.val = kInitialValue;
- }
-
- absl::memory_internal::uninitialized_default_construct_n(objs, len);
- for (auto& obj : objs) {
- EXPECT_EQ(obj.val, kExpectedValue);
- }
-}
-
} // namespace
diff --git a/absl/meta/type_traits.h b/absl/meta/type_traits.h
index 8d3264f1..457b8908 100644
--- a/absl/meta/type_traits.h
+++ b/absl/meta/type_traits.h
@@ -44,6 +44,7 @@
namespace absl {
namespace type_traits_internal {
+
template <typename... Ts>
struct VoidTImpl {
using type = void;
@@ -61,6 +62,49 @@ struct default_alignment_of_aligned_storage<Len,
static constexpr size_t value = Align;
};
+////////////////////////////////
+// Library Fundamentals V2 TS //
+////////////////////////////////
+
+// NOTE: The `is_detected` family of templates here differ from the library
+// fundamentals specification in that for library fundamentals, `Op<Args...>` is
+// evaluated as soon as the type `is_detected<Op, Args...>` undergoes
+// substitution, regardless of whether or not the `::value` is accessed. That
+// is inconsistent with all other standard traits and prevents lazy evaluation
+// in larger contexts (such as if the `is_detected` check is a trailing argument
+// of a `conjunction`. This implementation opts to instead be lazy in the same
+// way that the standard traits are (this "defect" of the detection idiom
+// specifications has been reported).
+
+template <class Enabler, template <class...> class Op, class... Args>
+struct is_detected_impl {
+ using type = std::false_type;
+};
+
+template <template <class...> class Op, class... Args>
+struct is_detected_impl<typename VoidTImpl<Op<Args...>>::type, Op, Args...> {
+ using type = std::true_type;
+};
+
+template <template <class...> class Op, class... Args>
+struct is_detected : is_detected_impl<void, Op, Args...>::type {};
+
+template <class Enabler, class To, template <class...> class Op, class... Args>
+struct is_detected_convertible_impl {
+ using type = std::false_type;
+};
+
+template <class To, template <class...> class Op, class... Args>
+struct is_detected_convertible_impl<
+ typename std::enable_if<std::is_convertible<Op<Args...>, To>::value>::type,
+ To, Op, Args...> {
+ using type = std::true_type;
+};
+
+template <class To, template <class...> class Op, class... Args>
+struct is_detected_convertible
+ : is_detected_convertible_impl<void, To, Op, Args...>::type {};
+
} // namespace type_traits_internal
// void_t()
diff --git a/absl/meta/type_traits_test.cc b/absl/meta/type_traits_test.cc
index 9dd95429..81b4bd32 100644
--- a/absl/meta/type_traits_test.cc
+++ b/absl/meta/type_traits_test.cc
@@ -34,6 +34,83 @@ struct simple_pair {
struct Dummy {};
+struct ReturnType {};
+struct ConvertibleToReturnType {
+ operator ReturnType() const; // NOLINT
+};
+
+// Unique types used as parameter types for testing the detection idiom.
+struct StructA {};
+struct StructB {};
+struct StructC {};
+
+struct TypeWithBarFunction {
+ template <class T,
+ absl::enable_if_t<std::is_same<T&&, StructA&>::value, int> = 0>
+ ReturnType bar(T&&, const StructB&, StructC&&) &&; // NOLINT
+};
+
+struct TypeWithBarFunctionAndConvertibleReturnType {
+ template <class T,
+ absl::enable_if_t<std::is_same<T&&, StructA&>::value, int> = 0>
+ ConvertibleToReturnType bar(T&&, const StructB&, StructC&&) &&; // NOLINT
+};
+
+template <class Class, class... Ts>
+using BarIsCallableImpl =
+ decltype(std::declval<Class>().bar(std::declval<Ts>()...));
+
+template <class Class, class... T>
+using BarIsCallable =
+ absl::type_traits_internal::is_detected<BarIsCallableImpl, Class, T...>;
+
+template <class Class, class... T>
+using BarIsCallableConv = absl::type_traits_internal::is_detected_convertible<
+ ReturnType, BarIsCallableImpl, Class, T...>;
+
+// NOTE: Test of detail type_traits_internal::is_detected.
+TEST(IsDetectedTest, BasicUsage) {
+ EXPECT_TRUE((BarIsCallable<TypeWithBarFunction, StructA&, const StructB&,
+ StructC>::value));
+ EXPECT_TRUE(
+ (BarIsCallable<TypeWithBarFunction, StructA&, StructB&, StructC>::value));
+ EXPECT_TRUE(
+ (BarIsCallable<TypeWithBarFunction, StructA&, StructB, StructC>::value));
+
+ EXPECT_FALSE((BarIsCallable<int, StructA&, const StructB&, StructC>::value));
+ EXPECT_FALSE((BarIsCallable<TypeWithBarFunction&, StructA&, const StructB&,
+ StructC>::value));
+ EXPECT_FALSE((BarIsCallable<TypeWithBarFunction, StructA, const StructB&,
+ StructC>::value));
+}
+
+// NOTE: Test of detail type_traits_internal::is_detected_convertible.
+TEST(IsDetectedConvertibleTest, BasicUsage) {
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunction, StructA&, const StructB&,
+ StructC>::value));
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunction, StructA&, StructB&,
+ StructC>::value));
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunction, StructA&, StructB,
+ StructC>::value));
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunctionAndConvertibleReturnType,
+ StructA&, const StructB&, StructC>::value));
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunctionAndConvertibleReturnType,
+ StructA&, StructB&, StructC>::value));
+ EXPECT_TRUE((BarIsCallableConv<TypeWithBarFunctionAndConvertibleReturnType,
+ StructA&, StructB, StructC>::value));
+
+ EXPECT_FALSE(
+ (BarIsCallableConv<int, StructA&, const StructB&, StructC>::value));
+ EXPECT_FALSE((BarIsCallableConv<TypeWithBarFunction&, StructA&,
+ const StructB&, StructC>::value));
+ EXPECT_FALSE((BarIsCallableConv<TypeWithBarFunction, StructA, const StructB&,
+ StructC>::value));
+ EXPECT_FALSE((BarIsCallableConv<TypeWithBarFunctionAndConvertibleReturnType&,
+ StructA&, const StructB&, StructC>::value));
+ EXPECT_FALSE((BarIsCallableConv<TypeWithBarFunctionAndConvertibleReturnType,
+ StructA, const StructB&, StructC>::value));
+}
+
TEST(VoidTTest, BasicUsage) {
StaticAssertTypeEq<void, absl::void_t<Dummy>>();
StaticAssertTypeEq<void, absl::void_t<Dummy, Dummy, Dummy>>();
@@ -718,8 +795,8 @@ TEST(TypeTraitsTest, TestDecay) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int[][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int());
- ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(float));
- ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(char, ...));
+ ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(float)); // NOLINT
+ ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(char, ...)); // NOLINT
}
struct TypeA {};
diff --git a/absl/strings/numbers_test.cc b/absl/strings/numbers_test.cc
index 24e7138c..8ebb090e 100644
--- a/absl/strings/numbers_test.cc
+++ b/absl/strings/numbers_test.cc
@@ -56,16 +56,11 @@ using testing::Eq;
using testing::MatchesRegex;
// Number of floats to test with.
-// 10,000,000 is a reasonable default for a test that only takes a few seconds.
+// 5,000,000 is a reasonable default for a test that only takes a few seconds.
// 1,000,000,000+ triggers checking for all possible mantissa values for
// double-precision tests. 2,000,000,000+ triggers checking for every possible
// single-precision float.
-#ifdef _MSC_VER
-// Use a smaller number on MSVC to avoid test time out (1 min)
const int kFloatNumCases = 5000000;
-#else
-const int kFloatNumCases = 10000000;
-#endif
// This is a slow, brute-force routine to compute the exact base-10
// representation of a double-precision floating-point number. It
diff --git a/absl/time/duration.cc b/absl/time/duration.cc
index c13fa79b..f402137b 100644
--- a/absl/time/duration.cc
+++ b/absl/time/duration.cc
@@ -895,13 +895,10 @@ bool ParseDuration(const std::string& dur_string, Duration* d) {
*d = dur;
return true;
}
-
bool ParseFlag(const std::string& text, Duration* dst, std::string* ) {
return ParseDuration(text, dst);
}
-std::string UnparseFlag(Duration d) {
- return FormatDuration(d);
-}
+std::string UnparseFlag(Duration d) { return FormatDuration(d); }
} // namespace absl
diff --git a/absl/time/duration_benchmark.cc b/absl/time/duration_benchmark.cc
index 54f89a1f..d5657bd5 100644
--- a/absl/time/duration_benchmark.cc
+++ b/absl/time/duration_benchmark.cc
@@ -27,47 +27,113 @@ namespace {
//
void BM_Duration_Factory_Nanoseconds(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Nanoseconds(1));
+ benchmark::DoNotOptimize(absl::Nanoseconds(i));
+ i += 314159;
}
}
BENCHMARK(BM_Duration_Factory_Nanoseconds);
void BM_Duration_Factory_Microseconds(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Microseconds(1));
+ benchmark::DoNotOptimize(absl::Microseconds(i));
+ i += 314;
}
}
BENCHMARK(BM_Duration_Factory_Microseconds);
void BM_Duration_Factory_Milliseconds(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Milliseconds(1));
+ benchmark::DoNotOptimize(absl::Milliseconds(i));
+ i += 1;
}
}
BENCHMARK(BM_Duration_Factory_Milliseconds);
void BM_Duration_Factory_Seconds(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Seconds(1));
+ benchmark::DoNotOptimize(absl::Seconds(i));
+ i += 1;
}
}
BENCHMARK(BM_Duration_Factory_Seconds);
void BM_Duration_Factory_Minutes(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Minutes(1));
+ benchmark::DoNotOptimize(absl::Minutes(i));
+ i += 1;
}
}
BENCHMARK(BM_Duration_Factory_Minutes);
void BM_Duration_Factory_Hours(benchmark::State& state) {
+ int64_t i = 0;
while (state.KeepRunning()) {
- benchmark::DoNotOptimize(absl::Hours(1));
+ benchmark::DoNotOptimize(absl::Hours(i));
+ i += 1;
}
}
BENCHMARK(BM_Duration_Factory_Hours);
+void BM_Duration_Factory_DoubleNanoseconds(benchmark::State& state) {
+ double d = 1;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Nanoseconds(d));
+ d = d * 1.00000001 + 1;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleNanoseconds);
+
+void BM_Duration_Factory_DoubleMicroseconds(benchmark::State& state) {
+ double d = 1e-3;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Microseconds(d));
+ d = d * 1.00000001 + 1e-3;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleMicroseconds);
+
+void BM_Duration_Factory_DoubleMilliseconds(benchmark::State& state) {
+ double d = 1e-6;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Milliseconds(d));
+ d = d * 1.00000001 + 1e-6;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleMilliseconds);
+
+void BM_Duration_Factory_DoubleSeconds(benchmark::State& state) {
+ double d = 1e-9;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Seconds(d));
+ d = d * 1.00000001 + 1e-9;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleSeconds);
+
+void BM_Duration_Factory_DoubleMinutes(benchmark::State& state) {
+ double d = 1e-9;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Minutes(d));
+ d = d * 1.00000001 + 1e-9;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleMinutes);
+
+void BM_Duration_Factory_DoubleHours(benchmark::State& state) {
+ double d = 1e-9;
+ while (state.KeepRunning()) {
+ benchmark::DoNotOptimize(absl::Hours(d));
+ d = d * 1.00000001 + 1e-9;
+ }
+}
+BENCHMARK(BM_Duration_Factory_DoubleHours);
+
//
// Arithmetic
//
diff --git a/absl/time/duration_test.cc b/absl/time/duration_test.cc
index 704684ed..7ae25dc6 100644
--- a/absl/time/duration_test.cc
+++ b/absl/time/duration_test.cc
@@ -16,7 +16,9 @@
#include <cmath>
#include <cstdint>
#include <ctime>
+#include <iomanip>
#include <limits>
+#include <random>
#include <string>
#include "gmock/gmock.h"
@@ -105,22 +107,22 @@ TEST(Duration, Factories) {
}
TEST(Duration, ToConversion) {
-#define TEST_DURATION_CONVERSION(UNIT) \
- do { \
- const absl::Duration d = absl::UNIT(1.5); \
- const absl::Duration z = absl::ZeroDuration(); \
- const absl::Duration inf = absl::InfiniteDuration(); \
- const double dbl_inf = std::numeric_limits<double>::infinity(); \
- EXPECT_EQ(kint64min, absl::ToInt64##UNIT(-inf)); \
- EXPECT_EQ(-1, absl::ToInt64##UNIT(-d)); \
- EXPECT_EQ(0, absl::ToInt64##UNIT(z)); \
- EXPECT_EQ(1, absl::ToInt64##UNIT(d)); \
- EXPECT_EQ(kint64max, absl::ToInt64##UNIT(inf)); \
- EXPECT_EQ(-dbl_inf, absl::ToDouble##UNIT(-inf)); \
- EXPECT_EQ(-1.5, absl::ToDouble##UNIT(-d)); \
- EXPECT_EQ(0, absl::ToDouble##UNIT(z)); \
- EXPECT_EQ(1.5, absl::ToDouble##UNIT(d)); \
- EXPECT_EQ(dbl_inf, absl::ToDouble##UNIT(inf)); \
+#define TEST_DURATION_CONVERSION(UNIT) \
+ do { \
+ const absl::Duration d = absl::UNIT(1.5); \
+ constexpr absl::Duration z = absl::ZeroDuration(); \
+ constexpr absl::Duration inf = absl::InfiniteDuration(); \
+ constexpr double dbl_inf = std::numeric_limits<double>::infinity(); \
+ EXPECT_EQ(kint64min, absl::ToInt64##UNIT(-inf)); \
+ EXPECT_EQ(-1, absl::ToInt64##UNIT(-d)); \
+ EXPECT_EQ(0, absl::ToInt64##UNIT(z)); \
+ EXPECT_EQ(1, absl::ToInt64##UNIT(d)); \
+ EXPECT_EQ(kint64max, absl::ToInt64##UNIT(inf)); \
+ EXPECT_EQ(-dbl_inf, absl::ToDouble##UNIT(-inf)); \
+ EXPECT_EQ(-1.5, absl::ToDouble##UNIT(-d)); \
+ EXPECT_EQ(0, absl::ToDouble##UNIT(z)); \
+ EXPECT_EQ(1.5, absl::ToDouble##UNIT(d)); \
+ EXPECT_EQ(dbl_inf, absl::ToDouble##UNIT(inf)); \
} while (0)
TEST_DURATION_CONVERSION(Nanoseconds);
@@ -1284,6 +1286,16 @@ TEST(Duration, SmallConversions) {
EXPECT_EQ(absl::Nanoseconds(1), absl::Seconds(0.875e-9));
EXPECT_EQ(absl::Nanoseconds(1), absl::Seconds(1.000e-9));
+ EXPECT_EQ(absl::ZeroDuration(), absl::Seconds(-0.124999999e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1) / 4, absl::Seconds(-0.125e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1) / 4, absl::Seconds(-0.250e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1) / 2, absl::Seconds(-0.375e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1) / 2, absl::Seconds(-0.500e-9));
+ EXPECT_EQ(-absl::Nanoseconds(3) / 4, absl::Seconds(-0.625e-9));
+ EXPECT_EQ(-absl::Nanoseconds(3) / 4, absl::Seconds(-0.750e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1), absl::Seconds(-0.875e-9));
+ EXPECT_EQ(-absl::Nanoseconds(1), absl::Seconds(-1.000e-9));
+
timespec ts;
ts.tv_sec = 0;
ts.tv_nsec = 0;
@@ -1313,6 +1325,86 @@ TEST(Duration, SmallConversions) {
EXPECT_THAT(ToTimeval(absl::Nanoseconds(2000)), TimevalMatcher(tv));
}
+void VerifySameAsMul(double time_as_seconds, int* const misses) {
+ auto direct_seconds = absl::Seconds(time_as_seconds);
+ auto mul_by_one_second = time_as_seconds * absl::Seconds(1);
+ if (direct_seconds != mul_by_one_second) {
+ if (*misses > 10) return;
+ ASSERT_LE(++(*misses), 10) << "Too many errors, not reporting more.";
+ EXPECT_EQ(direct_seconds, mul_by_one_second)
+ << "given double time_as_seconds = " << std::setprecision(17)
+ << time_as_seconds;
+ }
+}
+
+// For a variety of interesting durations, we find the exact point
+// where one double converts to that duration, and the very next double
+// converts to the next duration. For both of those points, verify that
+// Seconds(point) returns the same duration as point * Seconds(1.0)
+TEST(Duration, ToDoubleSecondsCheckEdgeCases) {
+ constexpr uint32_t kTicksPerSecond = absl::time_internal::kTicksPerSecond;
+ constexpr auto duration_tick = absl::time_internal::MakeDuration(0, 1u);
+ int misses = 0;
+ for (int64_t seconds = 0; seconds < 99; ++seconds) {
+ uint32_t tick_vals[] = {0, +999, +999999, +999999999, kTicksPerSecond - 1,
+ 0, 1000, 1000000, 1000000000, kTicksPerSecond,
+ 1, 1001, 1000001, 1000000001, kTicksPerSecond + 1,
+ 2, 1002, 1000002, 1000000002, kTicksPerSecond + 2,
+ 3, 1003, 1000003, 1000000003, kTicksPerSecond + 3,
+ 4, 1004, 1000004, 1000000004, kTicksPerSecond + 4,
+ 5, 6, 7, 8, 9};
+ for (uint32_t ticks : tick_vals) {
+ absl::Duration s_plus_t = absl::Seconds(seconds) + ticks * duration_tick;
+ for (absl::Duration d : {s_plus_t, -s_plus_t}) {
+ absl::Duration after_d = d + duration_tick;
+ EXPECT_NE(d, after_d);
+ EXPECT_EQ(after_d - d, duration_tick);
+
+ double low_edge = ToDoubleSeconds(d);
+ EXPECT_EQ(d, absl::Seconds(low_edge));
+
+ double high_edge = ToDoubleSeconds(after_d);
+ EXPECT_EQ(after_d, absl::Seconds(high_edge));
+
+ for (;;) {
+ double midpoint = low_edge + (high_edge - low_edge) / 2;
+ if (midpoint == low_edge || midpoint == high_edge) break;
+ absl::Duration mid_duration = absl::Seconds(midpoint);
+ if (mid_duration == d) {
+ low_edge = midpoint;
+ } else {
+ EXPECT_EQ(mid_duration, after_d);
+ high_edge = midpoint;
+ }
+ }
+ // Now low_edge is the highest double that converts to Duration d,
+ // and high_edge is the lowest double that converts to Duration after_d.
+ VerifySameAsMul(low_edge, &misses);
+ VerifySameAsMul(high_edge, &misses);
+ }
+ }
+ }
+}
+
+TEST(Duration, ToDoubleSecondsCheckRandom) {
+ std::random_device rd;
+ std::seed_seq seed({rd(), rd(), rd(), rd(), rd(), rd(), rd(), rd()});
+ std::mt19937_64 gen(seed);
+ // We want doubles distributed from 1/8ns up to 2^63, where
+ // as many values are tested from 1ns to 2ns as from 1sec to 2sec,
+ // so even distribute along a log-scale of those values, and
+ // exponentiate before using them. (9.223377e+18 is just slightly
+ // out of bounds for absl::Duration.)
+ std::uniform_real_distribution<double> uniform(std::log(0.125e-9),
+ std::log(9.223377e+18));
+ int misses = 0;
+ for (int i = 0; i < 1000000; ++i) {
+ double d = std::exp(uniform(gen));
+ VerifySameAsMul(d, &misses);
+ VerifySameAsMul(-d, &misses);
+ }
+}
+
TEST(Duration, ConversionSaturation) {
absl::Duration d;
diff --git a/absl/time/time.h b/absl/time/time.h
index 880fc783..c41cb89c 100644
--- a/absl/time/time.h
+++ b/absl/time/time.h
@@ -81,6 +81,7 @@ constexpr int64_t GetRepHi(Duration d);
constexpr uint32_t GetRepLo(Duration d);
constexpr Duration MakeDuration(int64_t hi, uint32_t lo);
constexpr Duration MakeDuration(int64_t hi, int64_t lo);
+inline Duration MakePosDoubleDuration(double n);
constexpr int64_t kTicksPerNanosecond = 4;
constexpr int64_t kTicksPerSecond = 1000 * 1000 * 1000 * kTicksPerNanosecond;
template <std::intmax_t N>
@@ -295,6 +296,39 @@ Duration Floor(Duration d, Duration unit);
// absl::Duration c = absl::Ceil(d, absl::Microseconds(1)); // 123457us
Duration Ceil(Duration d, Duration unit);
+// InfiniteDuration()
+//
+// Returns an infinite `Duration`. To get a `Duration` representing negative
+// infinity, use `-InfiniteDuration()`.
+//
+// Duration arithmetic overflows to +/- infinity and saturates. In general,
+// arithmetic with `Duration` infinities is similar to IEEE 754 infinities
+// except where IEEE 754 NaN would be involved, in which case +/-
+// `InfiniteDuration()` is used in place of a "nan" Duration.
+//
+// Examples:
+//
+// constexpr absl::Duration inf = absl::InfiniteDuration();
+// const absl::Duration d = ... any finite duration ...
+//
+// inf == inf + inf
+// inf == inf + d
+// inf == inf - inf
+// -inf == d - inf
+//
+// inf == d * 1e100
+// inf == inf / 2
+// 0 == d / inf
+// INT64_MAX == inf / d
+//
+// // Division by zero returns infinity, or INT64_MIN/MAX where appropriate.
+// inf == d / 0
+// INT64_MAX == d / absl::ZeroDuration()
+//
+// The examples involving the `/` operator above also apply to `IDivDuration()`
+// and `FDivDuration()`.
+constexpr Duration InfiniteDuration();
+
// Nanoseconds()
// Microseconds()
// Milliseconds()
@@ -344,7 +378,13 @@ Duration Milliseconds(T n) {
}
template <typename T, time_internal::EnableIfFloat<T> = 0>
Duration Seconds(T n) {
- return n * Seconds(1);
+ if (n >= 0) {
+ if (n >= std::numeric_limits<int64_t>::max()) return InfiniteDuration();
+ return time_internal::MakePosDoubleDuration(n);
+ } else {
+ if (n <= std::numeric_limits<int64_t>::min()) return -InfiniteDuration();
+ return -time_internal::MakePosDoubleDuration(-n);
+ }
}
template <typename T, time_internal::EnableIfFloat<T> = 0>
Duration Minutes(T n) {
@@ -439,39 +479,6 @@ std::chrono::seconds ToChronoSeconds(Duration d);
std::chrono::minutes ToChronoMinutes(Duration d);
std::chrono::hours ToChronoHours(Duration d);
-// InfiniteDuration()
-//
-// Returns an infinite `Duration`. To get a `Duration` representing negative
-// infinity, use `-InfiniteDuration()`.
-//
-// Duration arithmetic overflows to +/- infinity and saturates. In general,
-// arithmetic with `Duration` infinities is similar to IEEE 754 infinities
-// except where IEEE 754 NaN would be involved, in which case +/-
-// `InfiniteDuration()` is used in place of a "nan" Duration.
-//
-// Examples:
-//
-// constexpr absl::Duration inf = absl::InfiniteDuration();
-// const absl::Duration d = ... any finite duration ...
-//
-// inf == inf + inf
-// inf == inf + d
-// inf == inf - inf
-// -inf == d - inf
-//
-// inf == d * 1e100
-// inf == inf / 2
-// 0 == d / inf
-// INT64_MAX == inf / d
-//
-// // Division by zero returns infinity, or INT64_MIN/MAX where appropriate.
-// inf == d / 0
-// INT64_MAX == d / absl::ZeroDuration()
-//
-// The examples involving the `/` operator above also apply to `IDivDuration()`
-// and `FDivDuration()`.
-constexpr Duration InfiniteDuration();
-
// FormatDuration()
//
// Returns a std::string representing the duration in the form "72h3m0.5s".
@@ -492,12 +499,9 @@ inline std::ostream& operator<<(std::ostream& os, Duration d) {
// `ZeroDuration()`. Parses "inf" and "-inf" as +/- `InfiniteDuration()`.
bool ParseDuration(const std::string& dur_string, Duration* d);
-// ParseFlag()
-//
+// Support for flag values of type Duration. Duration flags must be specified
+// in a format that is valid input for absl::ParseDuration().
bool ParseFlag(const std::string& text, Duration* dst, std::string* error);
-
-// UnparseFlag()
-//
std::string UnparseFlag(Duration d);
// Time
@@ -991,9 +995,6 @@ bool ParseTime(const std::string& format, const std::string& input, Time* time,
bool ParseTime(const std::string& format, const std::string& input, TimeZone tz,
Time* time, std::string* err);
-// ParseFlag()
-// UnparseFlag()
-//
// Support for flag values of type Time. Time flags must be specified in a
// format that matches absl::RFC3339_full. For example:
//
@@ -1114,6 +1115,18 @@ constexpr Duration MakeDuration(int64_t hi, int64_t lo) {
return MakeDuration(hi, static_cast<uint32_t>(lo));
}
+// Make a Duration value from a floating-point number, as long as that number
+// is in the range [ 0 .. numeric_limits<int64_t>::max ), that is, as long as
+// it's positive and can be converted to int64_t without risk of UB.
+inline Duration MakePosDoubleDuration(double n) {
+ const int64_t int_secs = static_cast<int64_t>(n);
+ const uint32_t ticks =
+ static_cast<uint32_t>((n - int_secs) * kTicksPerSecond + 0.5);
+ return ticks < kTicksPerSecond
+ ? MakeDuration(int_secs, ticks)
+ : MakeDuration(int_secs + 1, ticks - kTicksPerSecond);
+}
+
// Creates a normalized Duration from an almost-normalized (sec,ticks)
// pair. sec may be positive or negative. ticks must be in the range
// -kTicksPerSecond < *ticks < kTicksPerSecond. If ticks is negative it
diff --git a/absl/types/internal/variant.h b/absl/types/internal/variant.h
index 7db5e053..7708e67c 100644
--- a/absl/types/internal/variant.h
+++ b/absl/types/internal/variant.h
@@ -1062,32 +1062,6 @@ struct OverloadSet<> {
static void Overload(...);
};
-////////////////////////////////
-// Library Fundamentals V2 TS //
-////////////////////////////////
-
-// TODO(calabrese): Consider moving this to absl/meta/type_traits.h
-
-// The following is a rough implementation of parts of the detection idiom.
-// It is used for the comparison operator checks.
-
-template <class Enabler, class To, template <class...> class Op, class... Args>
-struct is_detected_convertible_impl {
- using type = std::false_type;
-};
-
-template <class To, template <class...> class Op, class... Args>
-struct is_detected_convertible_impl<
- absl::enable_if_t<std::is_convertible<Op<Args...>, To>::value>, To, Op,
- Args...> {
- using type = std::true_type;
-};
-
-// NOTE: This differs from library fundamentals by being lazy.
-template <class To, template <class...> class Op, class... Args>
-struct is_detected_convertible
- : is_detected_convertible_impl<void, To, Op, Args...>::type {};
-
template <class T>
using LessThanResult = decltype(std::declval<T>() < std::declval<T>());
@@ -1107,6 +1081,8 @@ using EqualResult = decltype(std::declval<T>() == std::declval<T>());
template <class T>
using NotEqualResult = decltype(std::declval<T>() != std::declval<T>());
+using type_traits_internal::is_detected_convertible;
+
template <class... T>
using RequireAllHaveEqualT = absl::enable_if_t<
absl::conjunction<is_detected_convertible<bool, EqualResult, T>...>::value,