Abseil Common Libraries (C++) (grcp 依赖) https://abseil.io/
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// 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.
#ifndef ABSL_CONTAINER_INTERNAL_CONTAINER_H_
#define ABSL_CONTAINER_INTERNAL_CONTAINER_H_
#include <type_traits>
#include "absl/meta/type_traits.h"
Export of internal Abseil changes. -- 5da9755667df37e38ccaf6938c9f408e294110bb by Shaindel Schwartz <shaindel@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 232942734 -- b6fb275769c66fdd2bd92b119198c59e9a7dd737 by Samuel Benzaquen <sbenza@google.com>: Fix integral underflow when from-arg width is INT_MIN. PiperOrigin-RevId: 232888037 -- 4135dbba4a26c4642277fc2a7e2a833d593daa1c by Abseil Team <absl-team@google.com>: Add the insert_return_type alias to raw_hash_set. PiperOrigin-RevId: 232683892 -- 0b120b7d3693800bbb886f6fc607ae54a9338cb1 by Abseil Team <absl-team@google.com>: Macros to detect and disabled SafeStack https://clang.llvm.org/docs/SafeStack.html PiperOrigin-RevId: 232680114 -- a77b3fb533a9e37966d1d6ef5ccd09c73fff2ca1 by Abseil Team <absl-team@google.com>: Avoid potential red zone clobber Pushing on the stack on x86-64 may clobber local variables held below %rsp in the red zone. Avoid this by using lea on x86-64. PiperOrigin-RevId: 232592478 -- bf326a0eefa92f4e704287563df0c5a5b1873b6d by Eric Fiselier <ericwf@google.com>: Add additional tests for AbslHashValue. PiperOrigin-RevId: 232344325 -- 816e4f98fd7632c944c779db87b7dac4e138afcf by Eric Fiselier <ericwf@google.com>: Avoid upcoming GCC 9.0 warnings about base class init. Currently, in trunk, GCC has a new warning under -Wextra that diagnoses when a derived class fails to explicitly initialize the base class in a constructor initializer list. This patch avoids this warning. PiperOrigin-RevId: 232327626 -- 779c0f44b3c2b7a04d4bdf978641eb8180515bf6 by Eric Fiselier <ericwf@google.com>: Guard against C++2a char8_t change. PiperOrigin-RevId: 232326178 -- 41e5395b85bbbfb5bf418cc21b04ad4ccb15a284 by Eric Fiselier <ericwf@google.com>: Avoid Clang Warning PiperOrigin-RevId: 232138866 GitOrigin-RevId: 5da9755667df37e38ccaf6938c9f408e294110bb Change-Id: I49ee4f58db177b81b039d7d949f671c97c5a7933
6 years ago
#include "absl/types/optional.h"
namespace absl {
namespace container_internal {
template <class, class = void>
struct IsTransparent : std::false_type {};
template <class T>
struct IsTransparent<T, absl::void_t<typename T::is_transparent>>
: std::true_type {};
template <bool is_transparent>
struct KeyArg {
// Transparent. Forward `K`.
template <typename K, typename key_type>
using type = K;
};
template <>
struct KeyArg<false> {
// Not transparent. Always use `key_type`.
template <typename K, typename key_type>
using type = key_type;
};
Export of internal Abseil changes. -- 5da9755667df37e38ccaf6938c9f408e294110bb by Shaindel Schwartz <shaindel@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 232942734 -- b6fb275769c66fdd2bd92b119198c59e9a7dd737 by Samuel Benzaquen <sbenza@google.com>: Fix integral underflow when from-arg width is INT_MIN. PiperOrigin-RevId: 232888037 -- 4135dbba4a26c4642277fc2a7e2a833d593daa1c by Abseil Team <absl-team@google.com>: Add the insert_return_type alias to raw_hash_set. PiperOrigin-RevId: 232683892 -- 0b120b7d3693800bbb886f6fc607ae54a9338cb1 by Abseil Team <absl-team@google.com>: Macros to detect and disabled SafeStack https://clang.llvm.org/docs/SafeStack.html PiperOrigin-RevId: 232680114 -- a77b3fb533a9e37966d1d6ef5ccd09c73fff2ca1 by Abseil Team <absl-team@google.com>: Avoid potential red zone clobber Pushing on the stack on x86-64 may clobber local variables held below %rsp in the red zone. Avoid this by using lea on x86-64. PiperOrigin-RevId: 232592478 -- bf326a0eefa92f4e704287563df0c5a5b1873b6d by Eric Fiselier <ericwf@google.com>: Add additional tests for AbslHashValue. PiperOrigin-RevId: 232344325 -- 816e4f98fd7632c944c779db87b7dac4e138afcf by Eric Fiselier <ericwf@google.com>: Avoid upcoming GCC 9.0 warnings about base class init. Currently, in trunk, GCC has a new warning under -Wextra that diagnoses when a derived class fails to explicitly initialize the base class in a constructor initializer list. This patch avoids this warning. PiperOrigin-RevId: 232327626 -- 779c0f44b3c2b7a04d4bdf978641eb8180515bf6 by Eric Fiselier <ericwf@google.com>: Guard against C++2a char8_t change. PiperOrigin-RevId: 232326178 -- 41e5395b85bbbfb5bf418cc21b04ad4ccb15a284 by Eric Fiselier <ericwf@google.com>: Avoid Clang Warning PiperOrigin-RevId: 232138866 GitOrigin-RevId: 5da9755667df37e38ccaf6938c9f408e294110bb Change-Id: I49ee4f58db177b81b039d7d949f671c97c5a7933
6 years ago
// The node_handle concept from C++17.
// We specialize node_handle for sets and maps. node_handle_base holds the
// common API of both.
template <typename PolicyTraits, typename Alloc>
class node_handle_base {
protected:
using slot_type = typename PolicyTraits::slot_type;
public:
using allocator_type = Alloc;
constexpr node_handle_base() {}
node_handle_base(node_handle_base&& other) noexcept {
*this = std::move(other);
}
~node_handle_base() { destroy(); }
node_handle_base& operator=(node_handle_base&& other) noexcept {
destroy();
if (!other.empty()) {
alloc_ = other.alloc_;
PolicyTraits::transfer(alloc(), slot(), other.slot());
other.reset();
}
return *this;
}
bool empty() const noexcept { return !alloc_; }
explicit operator bool() const noexcept { return !empty(); }
allocator_type get_allocator() const { return *alloc_; }
protected:
friend struct CommonAccess;
node_handle_base(const allocator_type& a, slot_type* s) : alloc_(a) {
PolicyTraits::transfer(alloc(), slot(), s);
}
void destroy() {
if (!empty()) {
PolicyTraits::destroy(alloc(), slot());
reset();
}
}
void reset() {
assert(alloc_.has_value());
alloc_ = absl::nullopt;
}
slot_type* slot() const {
assert(!empty());
return reinterpret_cast<slot_type*>(std::addressof(slot_space_));
}
allocator_type* alloc() { return std::addressof(*alloc_); }
private:
absl::optional<allocator_type> alloc_;
mutable absl::aligned_storage_t<sizeof(slot_type), alignof(slot_type)>
slot_space_;
};
// For sets.
template <typename Policy, typename PolicyTraits, typename Alloc,
typename = void>
class node_handle : public node_handle_base<PolicyTraits, Alloc> {
using Base = typename node_handle::node_handle_base;
public:
using value_type = typename PolicyTraits::value_type;
constexpr node_handle() {}
value_type& value() const { return PolicyTraits::element(this->slot()); }
private:
friend struct CommonAccess;
node_handle(const Alloc& a, typename Base::slot_type* s) : Base(a, s) {}
};
// For maps.
template <typename Policy, typename PolicyTraits, typename Alloc>
class node_handle<Policy, PolicyTraits, Alloc,
absl::void_t<typename Policy::mapped_type>>
: public node_handle_base<PolicyTraits, Alloc> {
using Base = typename node_handle::node_handle_base;
public:
using key_type = typename Policy::key_type;
using mapped_type = typename Policy::mapped_type;
constexpr node_handle() {}
auto key() const -> decltype(PolicyTraits::key(this->slot())) {
return PolicyTraits::key(this->slot());
}
mapped_type& mapped() const {
return PolicyTraits::value(&PolicyTraits::element(this->slot()));
}
private:
friend struct CommonAccess;
node_handle(const Alloc& a, typename Base::slot_type* s) : Base(a, s) {}
};
// Provide access to non-public node-handle functions.
struct CommonAccess {
template <typename Node>
static auto GetSlot(const Node& node) -> decltype(node.slot()) {
return node.slot();
}
template <typename Node>
static void Reset(Node* node) {
node->reset();
}
template <typename T, typename... Args>
static T Make(Args&&... args) {
return T(std::forward<Args>(args)...);
}
};
// Implement the insert_return_type<> concept of C++17.
template <class Iterator, class NodeType>
struct InsertReturnType {
Iterator position;
bool inserted;
NodeType node;
};
} // namespace container_internal
Export of internal Abseil changes. -- 5da9755667df37e38ccaf6938c9f408e294110bb by Shaindel Schwartz <shaindel@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 232942734 -- b6fb275769c66fdd2bd92b119198c59e9a7dd737 by Samuel Benzaquen <sbenza@google.com>: Fix integral underflow when from-arg width is INT_MIN. PiperOrigin-RevId: 232888037 -- 4135dbba4a26c4642277fc2a7e2a833d593daa1c by Abseil Team <absl-team@google.com>: Add the insert_return_type alias to raw_hash_set. PiperOrigin-RevId: 232683892 -- 0b120b7d3693800bbb886f6fc607ae54a9338cb1 by Abseil Team <absl-team@google.com>: Macros to detect and disabled SafeStack https://clang.llvm.org/docs/SafeStack.html PiperOrigin-RevId: 232680114 -- a77b3fb533a9e37966d1d6ef5ccd09c73fff2ca1 by Abseil Team <absl-team@google.com>: Avoid potential red zone clobber Pushing on the stack on x86-64 may clobber local variables held below %rsp in the red zone. Avoid this by using lea on x86-64. PiperOrigin-RevId: 232592478 -- bf326a0eefa92f4e704287563df0c5a5b1873b6d by Eric Fiselier <ericwf@google.com>: Add additional tests for AbslHashValue. PiperOrigin-RevId: 232344325 -- 816e4f98fd7632c944c779db87b7dac4e138afcf by Eric Fiselier <ericwf@google.com>: Avoid upcoming GCC 9.0 warnings about base class init. Currently, in trunk, GCC has a new warning under -Wextra that diagnoses when a derived class fails to explicitly initialize the base class in a constructor initializer list. This patch avoids this warning. PiperOrigin-RevId: 232327626 -- 779c0f44b3c2b7a04d4bdf978641eb8180515bf6 by Eric Fiselier <ericwf@google.com>: Guard against C++2a char8_t change. PiperOrigin-RevId: 232326178 -- 41e5395b85bbbfb5bf418cc21b04ad4ccb15a284 by Eric Fiselier <ericwf@google.com>: Avoid Clang Warning PiperOrigin-RevId: 232138866 GitOrigin-RevId: 5da9755667df37e38ccaf6938c9f408e294110bb Change-Id: I49ee4f58db177b81b039d7d949f671c97c5a7933
6 years ago
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_CONTAINER_H_