mdebray/tvl-depot
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
No description
304 commits 5 branches 0 tags 172 MiB
CSS 33%
Nix 26.8%
Rust 19.3%
Haskell 5.8%
Emacs Lisp 4.5%
Other 10.1%
Find a file
Abseil Team 0dffca4e36 Export of internal Abseil changes. 
--
5804cc13b413412988248835459b90cd15ec43d9 by Abseil Team <absl-team@google.com>:

Mark raw_hash_set::clear() with the ABSL_ATTRIBUTE_REINITIALIZES attribute.

This prevents false positives in the clang-tidy check bugprone-use-after-move;
it allows reset() to be called on a moved-from raw_hash_set without any
warnings, and the raw_hash_set will thereafter be regarded as initialized again.

PiperOrigin-RevId: 230717196

--
ff5961a5600ae19b69a9cba6912126cdf2858f38 by CJ Johnson <johnsoncj@google.com>:

Swaps DisableIfIntegral<> for EnableIfInputIterator<> for Iterator member functions of InlinedVector

PiperOrigin-RevId: 230559521

--
3f9754ccbeecbd40f235c6f2465279e045ff51d9 by Derek Mauro <dmauro@google.com>:

Import GitHub PR 254
https://github.com/abseil/abseil-cpp/pull/254

Fixes warnings from -Wclass-memaccess (base_internal::ThreadIdentity?
with no trivial copy-assignment).

PiperOrigin-RevId: 230536048

--
8af03a654ce9a4a7f55384bc7eb1ed64878ac2ec by Chris Kennelly <ckennelly@google.com>:

absl: cap SpinLock backoff to 4ms

The current backoff logic has 3 problems:
1. It can produce too high values (up to 256ms), which can negatively
affect tail latency. The value was chosen long time ago and now it's
a good idea to reconsider it.
2. It does not have low bound, so on any iteration it can produce
a very small value that will lead to unnecessary cpu consumption.
3. It does not increase low bound with the number of iterations.
So if the SpinLock is actually somehow locked for a very prolonged time,
a waiter can still wake periodically.

Rework the logic to solve these problems.
Add lower bound of 128us, no code should rely on absence of episodic
delays in this range as they can occur everywhere.
Lower upper bound to 4ms. A thread sleeping for 4ms does not consume
significant cpu time (see below).
Grow lower bound with the number of iterations.

This is cpu consumption of a process doing usleep(x) in a loop
(sampled with ps):

    64us -> 4.0%
   128us -> 2.7%
   256us -> 3.5%
   512us -> 2.8%
  1024us -> 1.6%
  2048us -> 0.6%
  4096us -> 0.3%
  8192us -> 0.0%

Few millisecond sleeps do not consume significant time.

PiperOrigin-RevId: 230534015

--
37ebba92289ca556cb2412cd8b3cb4c1ead3def7 by Samuel Benzaquen <sbenza@google.com>:

Add override and dispose hooks to the hashtable sampler.

PiperOrigin-RevId: 230353438

--
89c8f90175233ce9964eb3412df04e8a3cff0c0f by Andy Getzendanner <durandal@google.com>:

Fix a comment typo.

PiperOrigin-RevId: 229986838
GitOrigin-RevId: 5804cc13b413412988248835459b90cd15ec43d9
Change-Id: Iedb5e2cc9c0b924635c1c87b537780ab6b5b899f
2019-01-24 11:10:30 -05:00
absl Export of internal Abseil changes. 2019-01-24 11:10:30 -05:00
CMake Export of internal Abseil changes. 2018-12-26 12:35:10 -05:00
.clang-format Add Google-style .clang-format file. 2017-10-12 13:01:26 -06:00
.gitignore Export of internal Abseil changes. 2018-12-07 14:40:28 -05:00
ABSEIL_ISSUE_TEMPLATE.md Changes imported from Abseil "staging" branch: 2018-02-01 10:36:37 -05:00
AUTHORS Initial Commit 2017-09-19 16:54:40 -04:00
CMakeLists.txt Export of internal Abseil changes. 2018-12-17 13:22:17 -05:00
conanfile.py Add note at top that this is supported best-effort 2018-12-20 13:51:25 -05:00
CONTRIBUTING.md Export of internal Abseil changes. 2018-10-15 15:32:46 -04:00
LICENSE Export of internal Abseil changes. 2018-12-21 14:43:20 -05:00
LTS.md Export of internal Abseil changes. 2018-12-21 14:43:20 -05:00
README.md Export of internal Abseil changes. 2018-10-22 15:01:16 -04:00
UPGRADES.md Export of internal Abseil changes. 2019-01-07 15:22:43 -05:00
WORKSPACE Export of internal Abseil changes. 2019-01-14 14:09:52 -05:00

README.md

Abseil - C++ Common Libraries

The repository contains the Abseil C++ library code. Abseil is an open-source collection of C++ code (compliant to C++11) designed to augment the C++ standard library.

Table of Contents

About Abseil

Abseil is an open-source collection of C++ library code designed to augment the C++ standard library. The Abseil library code is collected from Google's own C++ code base, has been extensively tested and used in production, and is the same code we depend on in our daily coding lives.

In some cases, Abseil provides pieces missing from the C++ standard; in others, Abseil provides alternatives to the standard for special needs we've found through usage in the Google code base. We denote those cases clearly within the library code we provide you.

Abseil is not meant to be a competitor to the standard library; we've just found that many of these utilities serve a purpose within our code base, and we now want to provide those resources to the C++ community as a whole.

Quickstart

If you want to just get started, make sure you at least run through the Abseil Quickstart. The Quickstart contains information about setting up your development environment, downloading the Abseil code, running tests, and getting a simple binary working.

Building Abseil

Bazel is the official build system for Abseil, which is supported on most major platforms (Linux, Windows, MacOS, for example) and compilers. See the quickstart for more information on building Abseil using the Bazel build system.

If you require CMake support, please check the CMake build instructions.

Codemap

Abseil contains the following C++ library components:

  • base Abseil Fundamentals
    The base library contains initialization code and other code which all other Abseil code depends on. Code within base may not depend on any other code (other than the C++ standard library).
  • algorithm
    The algorithm library contains additions to the C++ <algorithm> library and container-based versions of such algorithms.
  • container
    The container library contains additional STL-style containers, including Abseil's unordered "Swiss table" containers.
  • debugging
    The debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities.
  • hash
    The hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil.
  • memory
    The memory library contains C++11-compatible versions of std::make_unique() and related memory management facilities.
  • meta
    The meta library contains C++11-compatible versions of type checks available within C++14 and C++17 versions of the C++ <type_traits> library.
  • numeric
    The numeric library contains C++11-compatible 128-bit integers.
  • strings
    The strings library contains a variety of strings routines and utilities, including a C++11-compatible version of the C++17 std::string_view type.
  • synchronization
    The synchronization library contains concurrency primitives (Abseil's absl::Mutex class, an alternative to std::mutex) and a variety of synchronization abstractions.
  • time
    The time library contains abstractions for computing with absolute points in time, durations of time, and formatting and parsing time within time zones.
  • types
    The types library contains non-container utility types, like a C++11-compatible version of the C++17 std::optional type.
  • utility
    The utility library contains utility and helper code.

License

The Abseil C++ library is licensed under the terms of the Apache license. See LICENSE for more information.

Links

For more information about Abseil: