| commit | 85fdf501461e8ee00401f06ee6c7d21ac6622484 | [log] [tgz] |
|---|---|---|
| author | Victor Campos <victor.campos@arm.com> | Wed Jan 15 10:11:39 2025 +0000 |
| committer | GitHub <noreply@github.com> | Wed Jan 15 10:11:39 2025 +0000 |
| tree | b7433b5ccc1596daee74f0d17e6f132ee7af8520 | |
| parent | bd768246da23ad141d3e9303cf43fd4363a6d4f4 [diff] |
[Multilib] Custom flags YAML parsing (#122903) This patch is the first step to extend the current multilib system to support the selection of library variants which do not correspond to existing command-line options. Proposal can be found in https://discourse.llvm.org/t/rfc-multilib-custom-flags/81058 The multilib mechanism supports libraries that target code generation or language options such as `--target`, `-mcpu`, `-mfpu`, `-mbranch-protection`. However, some library variants are particular to features that do not correspond to any command-line options. Examples include variants for multithreading and semihosting. This work introduces a way to instruct the multilib system to consider these features in library selection. This particular patch comprises a new section in `multilib.yaml` to declare flags for which no option exists. Henceforth this sort of flag will be called `custom flag` for clarity. The `multilib.yaml` file will have a new section called Flags which contains the declarations of the target’s custom flags: ```yaml Flags: - Name: multithreaded Values: - Name: no-multithreaded MacroDefines: [__SINGLE_THREAD__] - Name: multithreaded Default: no-multithreaded - Name: io Values: - Name: io-none - Name: io-semihosting MacroDefines: [SEMIHOSTING] - Name: io-linux-syscalls MacroDefines: [LINUX_SYSCALLS, HOSTED=1] Default: io-none ``` - Name: the name to categorize a flag. - Values: a list of possible values. - Default: it specifies which value this flag should take if not specified in the command-line invocation. It must be one value from the Values field. Each flag Value follows this description: - Name (required): the name of the custom flag value (string). This is the string to be used in `-fmultilib-flag=<string>`. - MacroDefines (optional): a list of strings to be used as macro definitions. Each string is fed into the driver as ``-D<string>``. A Default value is useful to save users from specifying custom flags that have a most commonly used value. The namespace of flag values is common across all flags. This means that flag values must be unique.
Welcome to the LLVM project!
This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
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.
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.
Consult the Getting Started with LLVM page for information on building and running LLVM.
For information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Join the LLVM Discourse forums, Discord chat, LLVM Office Hours or Regular sync-ups.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.