![]() Add address space to indirect abi info and use it for kernels. Previously, indirect arguments assumed assumed a stack passed object in the alloca address space using byval. A stack pointer is unsuitable for kernel arguments, which are passed in a separate, constant buffer with a different address space. Start using the new byref for aggregate kernel arguments. Previously these were emitted as raw struct arguments, and turned into loads in the backend. These will lower identically, although with byref you now have the option of applying an explicit alignment. In the future, a reasonable implementation would use byref for all kernel arguments (this would be a practical problem at the moment due to losing things like noalias on pointer arguments). This is mostly to avoid fighting the optimizer's treatment of aggregate load/store. SROA and instcombine both turn aggregate loads and stores into a long sequence of element loads and stores, rather than the optimizable memcpy I would expect in this situation. Now an explicit memcpy will be introduced up-front which is better understood and helps eliminate the alloca in more situations. This skips using byref in the case where HIP kernel pointer arguments in structs are promoted to global pointers. At minimum an additional patch is needed to allow coercion with indirect arguments. This also skips using it for OpenCL due to the current workaround used to support kernels calling kernels. Distinct function bodies would need to be generated up front instead of emitting an illegal call. |
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---|---|---|
clang | ||
clang-tools-extra | ||
compiler-rt | ||
debuginfo-tests | ||
flang | ||
libc | ||
libclc | ||
libcxx | ||
libcxxabi | ||
libunwind | ||
lld | ||
lldb | ||
llvm | ||
mlir | ||
openmp | ||
parallel-libs | ||
polly | ||
pstl | ||
utils/arcanist | ||
.arcconfig | ||
.arclint | ||
.clang-format | ||
.clang-tidy | ||
.git-blame-ignore-revs | ||
.gitignore | ||
CONTRIBUTING.md | ||
README.md |
README.md
The LLVM Compiler Infrastructure
This directory and its sub-directories contain 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.
Getting Started with the LLVM System
Taken from https://llvm.org/docs/GettingStarted.html.
Overview
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 converts it 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 front end. 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.
Getting the Source Code and Building 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:
-
cd llvm-project
-
mkdir build
-
cd build
-
cmake -G <generator> [options] ../llvm
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='...'
--- semicolon-separated list of the LLVM sub-projects you'd like to additionally build. Can include any of: clang, clang-tools-extra, libcxx, libcxxabi, libunwind, lldb, compiler-rt, lld, polly, or debuginfo-tests.For example, to build LLVM, Clang, libcxx, and libcxxabi, use
-DLLVM_ENABLE_PROJECTS="clang;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
). -
-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 . [-- [options] <target>]
or your build system specified above directly.-
The default target (i.e.
ninja
ormake
) 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
, whereNNN
is the number of parallel jobs, e.g. the number of CPUs you have.
-
-
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.