Export of internal Abseil changes

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291f7ef542f73e4801ab5108014bc02344ef31df by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 437835981
Change-Id: I42fd92e74903894533ac9984d7f622e3ba20f468

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2e8caf1a57c50b518e05b4bca48e4fe1bb19af82 by Andy Getzendanner <durandal@google.com>:

Internal change

PiperOrigin-RevId: 437832673
Change-Id: I61b35089418d01a54cecf161b254b68252bebff3

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b927482ccc399f7e337b60582988b914d9946e4e by Derek Mauro <dmauro@google.com>:

Simplify endian intrinsics for modern compilers

All modern compilers have either __builtin_bswapN (gcc, clang) or
_byteswap_TYPE (MSVC).  The other intrinsic definitions are no longer
necessary.

PiperOrigin-RevId: 437772295
Change-Id: Ifb3d88ba24b9097f87ceb202272b36d2f5e5117f

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b6782a2247a16d5c14706a74ec577c19963d9f97 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 437373174
Change-Id: I0f77e1780dee90d7a3c32a08d96c4aeb624a57b4

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a53e0c724e37b0b01515a99bd25394b8e21ffdfc by Derek Mauro <dmauro@google.com>:

Unify detection of SSE2 and SSSE3 instruction sets and
include the proper headers

Fix the intrinsic implementation of FastHexToBufferZeroPad16 in
numbers.h which only relies on SSSE3, not SSE 4.2.
https://godbolt.org/z/Pf5bn1Yv9

Closes #639

PiperOrigin-RevId: 437286940
Change-Id: Ic97948399b61b91e9c0bccd09313b795b904d714

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f173f597cb2a75ef2a989f45a496334b85e6f40d by Abseil Team <absl-team@google.com>:

Change assertion function to enable clearer error messages.

PiperOrigin-RevId: 437227057
Change-Id: If420d2f63b51feef6648762f344d5be012cd9c85
GitOrigin-RevId: 291f7ef542f73e4801ab5108014bc02344ef31df
12 files changed
tree: 7b9193fc4b720bc8e767912b8a38f82c11e19569
  1. .github/
  2. absl/
  3. ci/
  4. CMake/
  5. .clang-format
  6. .gitignore
  7. ABSEIL_ISSUE_TEMPLATE.md
  8. AUTHORS
  9. BUILD.bazel
  10. CMakeLists.txt
  11. conanfile.py
  12. CONTRIBUTING.md
  13. create_lts.py
  14. FAQ.md
  15. LICENSE
  16. README.md
  17. UPGRADES.md
  18. WORKSPACE
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 and CMake are the official build systems for Abseil.

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 and CMake Quickstart.

Support

Abseil is officially supported on many platforms. See the Abseil platform support guide for details on supported operating systems, compilers, CPUs, etc.

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.
  • cleanup
    The cleanup library contains the control-flow-construct-like type absl::Cleanup which is used for executing a callback on scope exit.
  • 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.
  • profiling
    The profiling library contains utility code for profiling C++ entities. It is currently a private dependency of other Abseil libraries.
  • status
    The status contains abstractions for error handling, specifically absl::Status and absl::StatusOr<T>.
  • 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.

Releases

Abseil recommends users “live-at-head” (update to the latest commit from the master branch as often as possible). However, we realize this philosophy doesn't work for every project, so we also provide Long Term Support Releases to which we backport fixes for severe bugs. See our release management document for more details.

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: