5cca622310
Refactor the logic on CompilerInstance::loadModule and a couple of surrounding methods in order to clarify what's going on. - Rename ModuleLoader::loadModuleFromSource to compileModuleFromSource and fix its documentation, since it never loads a module. It just creates/compiles one. - Rename one of the overloads of compileModuleImpl to compileModule, making it more obvious which one calls the other. - Rename compileAndLoadModule to compileModuleAndReadAST. This clarifies the relationship between this helper and its caller, CompilerInstance::loadModule (the old name implied the opposite relationship). It also (correctly) indicates that more needs to be done to load the module than this function is responsible for. - Split findOrCompileModuleAndReadAST out of loadModule. Besides reducing nesting for this code thanks to early returns and the like, this refactor clarifies the logic in loadModule, particularly around calls to ModuleMap::cacheModuleLoad and ModuleMap::getCachedModuleLoad. findOrCompileModuleAndReadAST also breaks early if the initial ReadAST call returns Missing or OutOfDate, allowing the last ditch call to compileModuleAndReadAST to come at the end of the function body. - Additionally split out selectModuleSource, clarifying the logic due to early returns. - Add ModuleLoadResult::isNormal and OtherUncachedFailure, so that loadModule knows whether to cache the result. OtherUncachedFailure was added to keep this patch NFC, but there's a chance that these cases were uncached by accident, through copy/paste/modify failures. These should be audited as a follow-up (maybe we can eliminate this case). - Do *not* lift the setting of `ModuleLoadFailed = true` to loadModule because there isn't a clear pattern for when it's set. This should be reconsidered in a follow-up, in case it would be correct to set `ModuleLoadFailed` whenever no module is returned and the result is either Normal or OtherUncachedFailure. - Add some header documentation where it was missing, and fix it where it was wrong. This should have no functionality change. https://reviews.llvm.org/D70556 |
||
---|---|---|
clang | ||
clang-tools-extra | ||
compiler-rt | ||
debuginfo-tests | ||
libc | ||
libclc | ||
libcxx | ||
libcxxabi | ||
libunwind | ||
lld | ||
lldb | ||
llgo | ||
llvm | ||
openmp | ||
parallel-libs | ||
polly | ||
pstl | ||
.arcconfig | ||
.clang-format | ||
.clang-tidy | ||
.git-blame-ignore-revs | ||
.gitignore | ||
README.md |
README.md
The LLVM Compiler Infrastructure
This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments.
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 workflow and configuration to get and build the LLVM source:
-
Checkout LLVM (including related subprojects 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 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 subprojects 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 pathname 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).
-
Run your build tool of choice!
-
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 build 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
, usemake -j NNN
(NNN is the number of parallel jobs, use e.g. 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.