| commit | 486f3aef98fd56b4eef84eebe70d53cc02d22874 | [log] [tgz] |
|---|---|---|
| author | David Spickett <david.spickett@linaro.org> | Fri Apr 05 09:03:16 2024 +0100 |
| committer | Copybara-Service <copybara-worker@google.com> | Fri Apr 05 01:10:15 2024 -0700 |
| tree | 95dae8b6b452794e34b9bac4c6a936487e66e1a4 | |
| parent | 8f4c17bf902b42c4c475626d5f3aeb7f0aaa1688 [diff] |
[flang][clang] Add Visibility specific help text for options (#81869) And use it to print the correct default OpenMP version for flang and flang -fc1. This change adds an optional `HelpTextsForVariants` to options. This allows you to change the help text that gets shown in documentation and `--help` based on the program its being generated for. As `OptTable` needs to be constexpr compatible, I have used a std::array of help text variants. Each entry is: (list of visibilities) - > help text string So for the OpenMP version we have (flang, fc1) -> "OpenMP version for flang is...". So you can have multiple visibilities use the same string. The number of entries is currently set to 1, and the number of visibilities per entry is 2, because that's the maximum we need for now. The code is written so we can increase these numbers later, and the unused elements will be initialised. I have not applied this to group descriptions just because I don't know of one that needs changing. It could easily be enabled for those too if needed. There are minor changes to them just to get it all to compile. This approach of storing many help strings per option in the 1 driver library seemed preferable to making a whole new library for Flang (even if that would mostly be including stuff from Clang). GitOrigin-RevId: 7e958f64efea6cb824e96ace51e021afbc150922
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
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To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
Treatment of language extensions is covered in this document.
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