ac49500cd0
This reverts commit 940d0a310dca31ae97080b068cef92eadfee6367, effectively reapplying 84e8257937ec6a332aa0b688f4dce57016516ffd, after working around the compile errors on the bots that I wasn't seeing locally. I removed the `constexpr` from `OptionalStorage<FileEntryRef>` that I had cargo-culted from the generic version, since `FileEntryRef` isn't relevant in `constexpr` contexts anyway. The original commit message follows: Make a few changes to the `FileEntryRef` API in preparation for propagating it enough to remove `FileEntry::getName()`. - Allow `FileEntryRef` to degrade implicitly to `const FileEntry*`. This allows functions currently returning `const FileEntry *` to be updated to return `FileEntryRef` without requiring all callers to be updated in the same patch. This helps avoid both (a) massive patches where many fields and locals are updated simultaneously and (b) noisy incremental patches where the first patch adds `getFileEntry()` at call sites and the second patch removes it. (Once `FileEntryRef` is everywhere, we should remove this API.) - Change `operator==` to compare the underlying `FileEntry*`, ignoring any difference in the spelling of the filename. There were 0 users of the existing function because it's not useful. In case comparing the exact named reference becomes important, add/test `isSameRef`. - Add `==` comparisons between `FileEntryRef` and `const FileEntry *` (compares the `FileEntry*`). - Customize `OptionalStorage<FileEntryRef>` to be pointer-sized. Add a private constructor that initializes with `nullptr` and specialize `OptionalStorage` to use it. This unblocks updating fields in size-sensitive data structures that currently use `const FileEntry *`. - Add `OptionalFileEntryRefDegradesToFileEntryPtr`, a wrapper around `Optional<FileEntryRef>` that degrades to `const FileEntry*`. This facilitates future incremental patches, like the same operator on `FileEntryRef`. (Once `FileEntryRef` is everywhere, we should remove this class.) - Remove the unncessary `const` from the by-value return of `FileEntryRef::getName`. - Delete the unused function `FileEntry::isOpenForTests`. Note that there are still `FileEntry` APIs that aren't wrapped and I plan to deal with these separately / incrementally, as they are needed. Differential Revision: https://reviews.llvm.org/D89834
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:
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Checkout LLVM (including related sub-projects like Clang):
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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
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Configure and build LLVM and Clang:
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cd llvm-project -
mkdir build -
cd build -
cmake -G <generator> [options] ../llvmSome 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:
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-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).
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cmake --build . [-- [options] <target>]or your build system specified above directly.-
The default target (i.e.
ninjaormake) will build all of LLVM. -
The
check-alltarget (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, whereNNNis the number of parallel jobs, e.g. the number of CPUs you have.
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For more information see CMake
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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.