maurice/snix
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Export of internal Abseil changes.

Browse source 
--
fd86c60bac6c41f1629ce1ab7dc1c8edff398a59 by Alex Strelnikov <strel@google.com>:

Import PR: https://github.com/abseil/abseil-cpp/pull/243
Fix Windows ARM64 intrinsic use.

PiperOrigin-RevId: 228535649

--
a0ca663f606a3b31493683e405be2b1cff450894 by CJ Johnson <johnsoncj@google.com>:

Fixes issue of mixed signedness comparison

PiperOrigin-RevId: 228535623

--
d71aaa1705d7303b43fe02088fe07b153e647796 by Shaindel Schwartz <shaindel@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 228534365

--
c1b49d361aa880198e071f93997724bddbcd4760 by Samuel Benzaquen <sbenza@google.com>:

Internal cleanup

PiperOrigin-RevId: 228406627

--
0c4b1c2bed107698e209055b3431771d7a1bdba1 by Dave Walker <dawalker@google.com>:

Add comments about the purpose of container_internal::slot_type.

PiperOrigin-RevId: 228264537

--
060aa6077d2f3a0a129149e0644d19f2f521b241 by Abseil Team <absl-team@google.com>:

#include <cmath> in hashtablez_sampler.cc

Expected to fix the android build.

PiperOrigin-RevId: 228222550
GitOrigin-RevId: fd86c60bac6c41f1629ce1ab7dc1c8edff398a59
Change-Id: I26339fd4548c1a81b037cb52c26910d1bd850ea8
This commit is contained in:
Abseil Team 2019-01-09 09:55:36 -08:00 • committed by Shaindel Schwartz
parent 9449ae9439
commit 018b4db1d7
11 changed files with 105 additions and 33 deletions
Download patch file Download diff file Expand all files Collapse all files

27
absl/container/internal/container_memory.h
View file

@ -286,11 +286,30 @@ struct IsLayoutCompatible {
} // namespace memory_internal
// If kMutableKeys is false, only the value member is accessed.
// The internal storage type for key-value containers like flat_hash_map.
//
// If kMutableKeys is true, key is accessed through all slots while value and
// mutable_value are accessed only via INITIALIZED slots. Slots are created and
// destroyed via mutable_value so that the key can be moved later.
// It is convenient for the value_type of a flat_hash_map<K, V> to be
// pair<const K, V>; the "const K" prevents accidental modification of the key
// when dealing with the reference returned from find() and similar methods.
// However, this creates other problems; we want to be able to emplace(K, V)
// efficiently with move operations, and similarly be able to move a
// pair<K, V> in insert().
//
// The solution is this union, which aliases the const and non-const versions
// of the pair. This also allows flat_hash_map<const K, V> to work, even though
// that has the same efficiency issues with move in emplace() and insert() -
// but people do it anyway.
//
// If kMutableKeys is false, only the value member can be accessed.
//
// If kMutableKeys is true, key can be accessed through all slots while value
// and mutable_value must be accessed only via INITIALIZED slots. Slots are
// created and destroyed via mutable_value so that the key can be moved later.
//
// Accessing one of the union fields while the other is active is safe as
// long as they are layout-compatible, which is guaranteed by the definition of
// kMutableKeys. For C++11, the relevant section of the standard is
// https://timsong-cpp.github.io/cppwp/n3337/class.mem#19 (9.2.19)
template <class K, class V>
union slot_type {
private: