![]() Leverage the method OpenCL uses that adds C intrinsics when the lookup failed. There is no need to define C intrinsics in the header file any more. It could help to avoid the large header file to speed up the compilation of RVV source code. Besides that, only the C intrinsics used by the users will be added into the declaration table. This patch is based on https://reviews.llvm.org/D103228 and inspired by OpenCL implementation. ### Experimental Results #### TL;DR: - Binary size of clang increase ~200k, which is +0.07% for debug build and +0.13% for release build. - Single file compilation speed up ~33x for debug build and ~8.5x for release build - Regression time reduce ~10% (`ninja check-all`, enable all targets) #### Header size change ``` | size | LoC | ------------------------------ Before | 4,434,725 | 69,749 | After | 6,140 | 162 | ``` #### Single File Compilation Time Testcase: ``` #include <riscv_vector.h> vint32m1_t test_vadd_vv_vfloat32m1_t(vint32m1_t op1, vint32m1_t op2, size_t vl) { return vadd(op1, op2, vl); } ``` ##### Debug build: Before: ``` real 0m19.352s user 0m19.252s sys 0m0.092s ``` After: ``` real 0m0.576s user 0m0.552s sys 0m0.024s ``` ~33x speed up for debug build ##### Release build: Before: ``` real 0m0.773s user 0m0.741s sys 0m0.032s ``` After: ``` real 0m0.092s user 0m0.080s sys 0m0.012s ``` ~8.5x speed up for release build #### Regression time Note: the failed case is `tools/llvm-debuginfod-find/debuginfod.test` which is unrelated to this patch. ##### Debug build Before: ``` Testing Time: 1358.38s Skipped : 11 Unsupported : 446 Passed : 75767 Expectedly Failed: 190 Failed : 1 ``` After ``` Testing Time: 1220.29s Skipped : 11 Unsupported : 446 Passed : 75767 Expectedly Failed: 190 Failed : 1 ``` ##### Release build Before: ``` Testing Time: 381.98s Skipped : 12 Unsupported : 1407 Passed : 74765 Expectedly Failed: 176 Failed : 1 ``` After: ``` Testing Time: 346.25s Skipped : 12 Unsupported : 1407 Passed : 74765 Expectedly Failed: 176 Failed : 1 ``` #### Binary size of clang ##### Debug build Before ``` text data bss dec hex filename 335261851 12726004 552812 348540667 14c64efb bin/clang ``` After ``` text data bss dec hex filename 335442803 12798708 552940 348794451 14ca2e53 bin/clang ``` +253K, +0.07% code size ##### Release build Before ``` text data bss dec hex filename 144123975 8374648 483140 152981763 91e5103 bin/clang ``` After ``` text data bss dec hex filename 144255762 8447296 483268 153186326 9217016 bin/clang ``` +204K, +0.13% Authored-by: Kito Cheng <kito.cheng@sifive.com> Co-Authored-by: Hsiangkai Wang <kai.wang@sifive.com> Reviewed By: khchen, aaron.ballman Differential Revision: https://reviews.llvm.org/D111617 |
||
---|---|---|
.github | ||
bolt | ||
clang | ||
clang-tools-extra | ||
cmake | ||
compiler-rt | ||
cross-project-tests | ||
flang | ||
libc | ||
libclc | ||
libcxx | ||
libcxxabi | ||
libunwind | ||
lld | ||
lldb | ||
llvm | ||
llvm-libgcc | ||
mlir | ||
openmp | ||
polly | ||
pstl | ||
runtimes | ||
third-party | ||
utils | ||
.arcconfig | ||
.arclint | ||
.clang-format | ||
.clang-tidy | ||
.git-blame-ignore-revs | ||
.gitignore | ||
.mailmap | ||
CONTRIBUTING.md | ||
README.md | ||
SECURITY.md |
README.md
The LLVM Compiler Infrastructure
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.
Getting Started with the LLVM System
Taken from here.
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 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.
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
-
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 inLLVM_ENABLE_PROJECTS
or inLLVM_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
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 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.
Getting in touch
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.