|tagger||Tom Stellard <firstname.lastname@example.org>||Tue Feb 07 22:44:33 2023 -0800|
|author||Paul Walker <email@example.com>||Wed Jan 18 16:33:42 2023 +0000|
|committer||Tom Stellard <firstname.lastname@example.org>||Tue Feb 07 21:37:09 2023 -0800|
[SVE] Fix incorrect lowering of predicate permute builtins. When lowering predicate permute builtins we incorrectly assume only the typically "active" bits for the specified element type play a role with all other bits zero'd. This is not the case because all bits are significant, with the element type specifying how they are grouped: b8 - permute using a block size of 1 bit b16 - permute using a block size of 2 bits b32 - permute using a block size of 4 bits b64 - permute using a block size of 8 bits The affected builtins are svrev, svtrn1, svtrn2, svuzp1, svuzp2, svzip1 and svzip2. This patch adds new intrinsics to support these operations and changes the builtin lowering code to emit them. The b8 case remains unchanged because for that operation the existing intrinsics work as required and their support for other predicate types has been maintained as useful if only as a way to test the correctness of their matching ISD nodes that code generation relies on. Differential Revision: https://reviews.llvm.org/D142065 (cherry picked from commit 26b79ca3fafc525225090646d42837368b3763c3)
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.
The LLVM Getting Started documentation may be out of date.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:
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_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
For example, to build LLVM, Clang, libcxx, and libcxxabi, use
-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.
make) will build all of LLVM.
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
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
For more information see CMake.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.