Initial support for loongarch64-unknown-linux-gnu
Hi, We hope to add a new port in rust for LoongArch.
LoongArch intro
LoongArch is a RISC style ISA which is independently designed by Loongson
Technology in China. It is divided into two versions, the 32-bit version (LA32)
and the 64-bit version (LA64). LA64 applications have application-level
backward binary compatibility with LA32 applications. LoongArch is composed of
a basic part (Loongson Base) and an expanded part. The expansion part includes
Loongson Binary Translation (LBT), Loongson VirtualiZation (LVZ), Loongson SIMD
EXtension (LSX) and Loongson Advanced SIMD EXtension(LASX).
Currently the LA464 processor core supports LoongArch ISA and the Loongson
3A5000 processor integrates 4 64-bit LA464 cores. LA464 is a four-issue 64-bit
high-performance processor core. It can be used as a single core for high-end
embedded and desktop applications, or as a basic processor core to form an
on-chip multi-core system for server and high-performance machine applications.
Documentations:
ISA:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html
ABI:
https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html
More docs can be found at:
https://loongson.github.io/LoongArch-Documentation/README-EN.html
Since last year, we have locally adapted two versions of rust, rust1.41 and rust1.57, and completed the test locally.
I'm not sure if I'm submitting all the patches at once, so I split up the patches and here's one of the commits
- Link to more documentation
- Move `changelog-seen` into the "Global Settings" section
- Update incorrect comments on `llvm.link-shared` and
`rust.debug-assertions`
- Use the correct default in the commented-out example more often
- Clarify that `docs` and `compiler-docs` only control the default,
they're not a hard-off switch.
- Document `-vvv` and `local-rebuild`
- Minor improvements to doc-comments in config.toml.example
This also sets `download-rustc = false`; that was already the default,
but it will be helpful in case the default changes
(https://jyn.dev/2023/01/12/Bootstrapping-Rust-in-2023.html).
Add `dist.compression-profile` option to control compression speed
PR #108534 reduced the size of compressed archives, but (as expected) it also resulted in way longer compression times and memory usage during compression.
It's desirable to keep status quo (smaller archives but more CI usage), but it should also be configurable so that downstream users don't have to waste that much time on CI. As a data point, this resulted in doubling the time of Ferrocene's dist jobs, and required us to increase the RAM allocation for one of such jobs.
This PR adds a new `config.toml` setting, `dist.compression-profile`. The values can be:
* `fast`: equivalent to the gzip and xz preset of "1"
* `balanced`: equivalent to the gzip and xz preset of "6" (the CLI defaults as far as I'm aware)
* `best`: equivalent to the gzip present of "9", and our custom xz profile
The default has also been moved back to `balanced`, to try and avoid the compression time regression for downstream users. I don't feel too strongly on the default, and I'm open to changing it.
Also, for the `best` profile the XZ settings do not match the "9" preset used by the CLI, and it might be confusing. Should we create a `custom-rustc-ci`/`ultra` profile for that?
r? ``@Mark-Simulacrum``
