| commit | e3626aae549c1ba4594f18e19258b90fce26b55b | [log] [tgz] |
|---|---|---|
| author | Victor Costan <pwnall@chromium.org> | Sat Nov 14 06:42:49 2020 +0000 |
| committer | Copybara-Service <copybara-worker@google.com> | Fri Nov 13 22:52:47 2020 -0800 |
| tree | ccbb5a18cde7273514a09920d8d96b9c214fc7f5 | |
| parent | 57b05d3c2e554abc8367fe6682e3ffbbf1fe3e73 [diff] |
Require SSE3 on x86 platforms. Before this CL, Chrome was built assuming SSE2 support on Windows, Linux, Chrome OS, and Android. This CL raises the assumption to SSE3 on all these platforms. This CL is a no-op for MSVC builds, which don't have a way to explicitly target SSE3. This CL does not impact Mac, where we only support 64-bit builds, which allows us to assume SSSE3 support. (The first 64-bit Intel Mac used the Core 2 microarchitecture.) This CL will not have a usage impact on Chrome OS, which already assumes SSE3 support, and on Android, where we require Lollipop+, which is only used in phones with SSSE3+ support. This CL will have a tiny impact on Windows and Linux usage. The impact has been quantified and deemed acceptable. Impacted users are receiving a notification starting in M87. Confusingly, "SSSE3" is not a typo of "SSE3". It is the next step up after SSE3, and before SSE4. This CL will cause Chrome to require SSE3. Targeting SSSE3 is future work. More details can be found in the design doc linked in the attached bug. Bug: 1123353 Change-Id: If93aa9d37e75f3068b06c42f7412c7c4578f3b9f Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2311044 Reviewed-by: Nico Weber <thakis@chromium.org> Reviewed-by: Greg Thompson <grt@chromium.org> Reviewed-by: Scott Violet <sky@chromium.org> Commit-Queue: Victor Costan <pwnall@chromium.org> Cr-Commit-Position: refs/heads/master@{#827575} GitOrigin-RevId: 5bb2864fdd57e45c84459520234b37a01e7a015a
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.
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.
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.
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.
Abseil contains the following C++ library components:
base Abseil Fundamentals 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 algorithm library contains additions to the C++ <algorithm> library and container-based versions of such algorithms.container container library contains additional STL-style containers, including Abseil's unordered “Swiss table” containers.debugging debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities.hash hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil.memory memory library contains C++11-compatible versions of std::make_unique() and related memory management facilities.meta 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 numeric library contains C++11-compatible 128-bit integers.strings 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 synchronization library contains concurrency primitives (Abseil's absl::Mutex class, an alternative to std::mutex) and a variety of synchronization abstractions.time time library contains abstractions for computing with absolute points in time, durations of time, and formatting and parsing time within time zones.types types library contains non-container utility types, like a C++11-compatible version of the C++17 std::optional type.utility utility library contains utility and helper code.The Abseil C++ library is licensed under the terms of the Apache license. See LICENSE for more information.
For more information about Abseil: