| commit | 4d8268fbf4cd30d39530622b7f1dc487122b4f3c | [log] [tgz] |
|---|---|---|
| author | Mark de Wever <[email protected]> | Sun Oct 03 11:11:53 2021 |
| committer | Mark de Wever <[email protected]> | Wed May 18 18:11:36 2022 |
| tree | d792a0db11e3b879e7f787107f914c7eec080a6e | |
| parent | f0e61029506fd63bb300f2dbbd65ba792e4ef3a2 [diff] |
[libc++][format] Improve format-arg-store. This optimizes the __format_arg_store type to allow a more efficient storage of the basic_format_args. It stores the data in two arrays: - A struct with the tag of the exposition only variant's type and the offset of the element in the data array. Since this array only depends on the type information it's calculated at compile time and can be shared by different instances of this class. - The arguments converted to the types used in the exposition only variant of basic_format_arg. This means the packed data can be directly copied to an element of this variant. The new code uses rvalue reference arguments in preparation for P2418. The handle class also has some changes to prepare for P2418. The real changed for P2418 will be done separately, but these parts make it easier to implement that paper. Some parts of existing test code are removed since they were no longer valid after the changes, but new tests have been added. Implements parts of: - P2418 Add support for std::generator-like types to std::format Completes: - LWG3473 Normative encouragement in non-normative note Depends on D121138 Reviewed By: #libc, vitaut, Mordante Differential Revision: https://reviews.llvm.org/D121514
This directory and its sub-directories contain the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The README briefly describes how to get started with building LLVM. For more information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Taken from here.
Welcome to the LLVM project!
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer. It also contains basic regression tests.
C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
The LLVM Getting Started documentation may be out of date. The Clang Getting Started page might have more accurate information.
This is an example work-flow and configuration to get and build the LLVM source:
Checkout LLVM (including related sub-projects like Clang):
git clone https://github.com/llvm/llvm-project.git
Or, on windows, git clone --config core.autocrlf=false https://github.com/llvm/llvm-project.git
Configure and build LLVM and Clang:
cd llvm-project
cmake -S llvm -B build -G <generator> [options]
Some common build system generators are:
Ninja --- for generating Ninja build files. Most llvm developers use Ninja.Unix Makefiles --- for generating make-compatible parallel makefiles.Visual Studio --- for generating Visual Studio projects and solutions.Xcode --- for generating Xcode projects.Some common options:
-DLLVM_ENABLE_PROJECTS='...' and -DLLVM_ENABLE_RUNTIMES='...' --- semicolon-separated list of the LLVM sub-projects and runtimes you'd like to additionally build. LLVM_ENABLE_PROJECTS can include any of: clang, clang-tools-extra, cross-project-tests, flang, libc, libclc, lld, lldb, mlir, openmp, polly, or pstl. LLVM_ENABLE_RUNTIMES can include any of libcxx, libcxxabi, libunwind, compiler-rt, libc or openmp. Some runtime projects can be specified either in LLVM_ENABLE_PROJECTS or in LLVM_ENABLE_RUNTIMES.
For example, to build LLVM, Clang, libcxx, and libcxxabi, use -DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi".
-DCMAKE_INSTALL_PREFIX=directory --- Specify for directory the full path name of where you want the LLVM tools and libraries to be installed (default /usr/local). Be careful if you install runtime libraries: if your system uses those provided by LLVM (like libc++ or libc++abi), you must not overwrite your system's copy of those libraries, since that could render your system unusable. In general, using something like /usr is not advised, but /usr/local is fine.
-DCMAKE_BUILD_TYPE=type --- Valid options for type are Debug, Release, RelWithDebInfo, and MinSizeRel. Default is Debug.
-DLLVM_ENABLE_ASSERTIONS=On --- Compile with assertion checks enabled (default is Yes for Debug builds, No for all other build types).
cmake --build build [-- [options] <target>] or your build system specified above directly.
The default target (i.e. ninja or make) will build all of LLVM.
The check-all target (i.e. ninja check-all) will run the regression tests to ensure everything is in working order.
CMake will generate targets for each tool and library, and most LLVM sub-projects generate their own check-<project> target.
Running a serial build will be slow. To improve speed, try running a parallel build. That's done by default in Ninja; for make, use the option -j NNN, where NNN is the number of parallel jobs to run. In most cases, you get the best performance if you specify the number of CPU threads you have. On some Unix systems, you can specify this with -j$(nproc).
For more information see CMake.
Consult the Getting Started with LLVM page for detailed information on configuring and compiling LLVM. You can visit Directory Layout to learn about the layout of the source code tree.
Join LLVM Discourse forums, discord chat or #llvm IRC channel on OFTC.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.