
This removes `WasmTagType`. `WasmTagType` contained an attribute and a signature index: ``` struct WasmTagType { uint8_t Attribute; uint32_t SigIndex; }; ``` Currently the attribute field is not used and reserved for future use, and always 0. And that this class contains `SigIndex` as its property is a little weird in the place, because the tag type's signature index is not an inherent property of a tag but rather a reference to another section that changes after linking. This makes tag handling in the linker also weird that tag-related methods are taking both `WasmTagType` and `WasmSignature` even though `WasmTagType` contains a signature index. This is because the signature index changes in linking so it doesn't have any info at this point. This instead moves `SigIndex` to `struct WasmTag` itself, as we did for `struct WasmFunction` in D111104. In this CL, in lib/MC and lib/Object, this now treats tag types in the same way as function types. Also in YAML, this removes `struct Tag`, because now it only contains the tag index. Also tags set `SigIndex` in `WasmImport` union, as functions do. I think this makes things simpler and makes tag handling more in line with function handling. These two shares similar properties in that both of them have signatures, but they are kind of nominal so having the same signature doesn't mean they are the same element. Also a drive-by fix: the reserved 'attirubute' part's encoding changed from uleb32 to uint8 a while ago. This was fixed in lib/MC and lib/Object but not in YAML. This doesn't change object files because the field's value is always 0 and its encoding is the same for the both encoding. This is effectively NFC; I didn't mark it as such just because it changed YAML test results. Reviewed By: sbc100, tlively Differential Revision: https://reviews.llvm.org/D111086
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 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 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
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Or, on windows,
git clone --config core.autocrlf=false https://github.com/llvm/llvm-project.git
-
-
Configure and build LLVM and Clang:
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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='...'
--- semicolon-separated list of the LLVM sub-projects you'd like to additionally build. Can include any of: clang, clang-tools-extra, compiler-rt,cross-project-tests, flang, libc, libclc, libcxx, libcxxabi, libunwind, lld, lldb, mlir, openmp, parallel-libs, polly, or pstl.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 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.