86 lines
2.9 KiB
C++
86 lines
2.9 KiB
C++
// 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
|
|
//
|
|
// https://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.
|
|
//
|
|
// Provides the internal API for hashtable_debug.h.
|
|
|
|
#ifndef ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
|
|
#define ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
|
|
|
|
#include <cstddef>
|
|
|
|
#include <algorithm>
|
|
#include <type_traits>
|
|
#include <vector>
|
|
|
|
#include "absl/base/config.h"
|
|
|
|
namespace absl {
|
|
ABSL_NAMESPACE_BEGIN
|
|
namespace container_internal {
|
|
namespace hashtable_debug_internal {
|
|
|
|
// If it is a map, call get<0>().
|
|
using std::get;
|
|
template <typename T, typename = typename T::mapped_type>
|
|
auto GetKey(const typename T::value_type& pair, int) -> decltype(get<0>(pair)) {
|
|
return get<0>(pair);
|
|
}
|
|
|
|
// If it is not a map, return the value directly.
|
|
template <typename T>
|
|
const typename T::key_type& GetKey(const typename T::key_type& key, char) {
|
|
return key;
|
|
}
|
|
|
|
// Containers should specialize this to provide debug information for that
|
|
// container.
|
|
template <class Container, typename Enabler = void>
|
|
struct HashtableDebugAccess {
|
|
// Returns the number of probes required to find `key` in `c`. The "number of
|
|
// probes" is a concept that can vary by container. Implementations should
|
|
// return 0 when `key` was found in the minimum number of operations and
|
|
// should increment the result for each non-trivial operation required to find
|
|
// `key`.
|
|
//
|
|
// The default implementation uses the bucket api from the standard and thus
|
|
// works for `std::unordered_*` containers.
|
|
static size_t GetNumProbes(const Container& c,
|
|
const typename Container::key_type& key) {
|
|
if (!c.bucket_count()) return {};
|
|
size_t num_probes = 0;
|
|
size_t bucket = c.bucket(key);
|
|
for (auto it = c.begin(bucket), e = c.end(bucket);; ++it, ++num_probes) {
|
|
if (it == e) return num_probes;
|
|
if (c.key_eq()(key, GetKey<Container>(*it, 0))) return num_probes;
|
|
}
|
|
}
|
|
|
|
// Returns the number of bytes requested from the allocator by the container
|
|
// and not freed.
|
|
//
|
|
// static size_t AllocatedByteSize(const Container& c);
|
|
|
|
// Returns a tight lower bound for AllocatedByteSize(c) where `c` is of type
|
|
// `Container` and `c.size()` is equal to `num_elements`.
|
|
//
|
|
// static size_t LowerBoundAllocatedByteSize(size_t num_elements);
|
|
};
|
|
|
|
} // namespace hashtable_debug_internal
|
|
} // namespace container_internal
|
|
ABSL_NAMESPACE_END
|
|
} // namespace absl
|
|
|
|
#endif // ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
|