Add rlib digest to identify Rust object files
This adds a metadata entry to `rlib` archives that lists which members are Rust object files instead of relying on the filename heuristic in `looks_like_rust_object.file`. I also added a fallback to the old behavior for `rlibs` built by older compilers.
Part of https://github.com/rust-lang/rust/issues/138243.
In cg_gcc ModuleBuffer already only contains a path anyway. And for
moving LTO into -Zlink-only we will need to serialize MaybeLtoModules.
By storing a path cached modules we avoid writing them to the disk a
second time during serialization of MaybeLtoModules.
Add `-Zsanitize=kernel-hwaddress`
The Linux kernel has a config option called `CONFIG_KASAN_SW_TAGS` that enables `-fsanitize=kernel-hwaddress`. This is not supported by Rust.
One slightly awkward detail is that `#[sanitize(address = "off")]` applies to both `-Zsanitize=address` and `-Zsanitize=kernel-address`. Probably it was done this way because both are the same LLVM pass. I replicated this logic here for hwaddress, but it might be undesirable.
Note that `#[sanitize(kernel_hwaddress = "off")]` could be supported as an annotation on statics, but since it's also missing for `#[sanitize(hwaddress = "off")]`, I did not add it.
MCP: https://github.com/rust-lang/compiler-team/issues/975
Tracking issue: https://github.com/rust-lang/rust/issues/154171
cc @rcvalle @maurer @ojeda
Unknown -> Unsupported compression algorithm
Both zstd and zlib are *known* compression algorithms, they just may not be supported by the backend. We shouldn't mislead users into e.g. thinking they made a typo.
cc https://github.com/rust-lang/rust/issues/120953
Rename `target.abi` to `target.cfg_abi` and enum-ify llvm_abiname
See [Zulip](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/De-spaghettifying.20ABI.20controls/with/578893542) for more context. Discussed a bit in https://github.com/rust-lang/rust/pull/153769#discussion_r2934399038 too.
This renames `target.abi` to `target.cfg_abi` to make it less likely that someone will use it to determine things about the actual ccABI, i.e. the calling convention used on the target. `target.abi` does not control that calling convention, it just *sometimes* informs the user about that calling convention (and also about other aspects of the ABI).
Also turn llvm_abiname into an enum to make it more natural to match on.
Cc @workingjubilee @madsmtm
Both zstd and zlib are *known* compression algorithms, they just may not
be supported by the backend. We shouldn't mislead users into e.g.
thinking they made a typo.
As far as I can tell it was introduced to allow fat LTO with
-Clinker-plugin-lto. Later a change was made to automatically disable
ThinLTO summary generation when -Clinker-plugin-lto -Clto=fat is used,
so we can safely remove it.
Add -Z large-data-threshold
This flag allows specifying the threshold size for placing static data in large data sections when using the medium code model on x86-64.
When using -Ccode-model=medium, data smaller than this threshold uses RIP-relative addressing (32-bit offsets), while larger data uses absolute 64-bit addressing. This allows the compiler to generate more efficient code for smaller data while still supporting data larger than 2GB.
This mirrors the -mlarge-data-threshold flag available in GCC and Clang. The default threshold is 65536 bytes (64KB) if not specified, matching LLVM's default behavior.
This flag allows specifying the threshold size for placing static data
in large data sections when using the medium code model on x86-64.
When using -Ccode-model=medium, data smaller than this threshold uses
RIP-relative addressing (32-bit offsets), while larger data uses
absolute 64-bit addressing. This allows the compiler to generate more
efficient code for smaller data while still supporting data larger than
2GB.
This mirrors the -mlarge-data-threshold flag available in GCC and Clang.
The default threshold is 65536 bytes (64KB) if not specified, matching
LLVM's default behavior.
remove llvm_enzyme and enzyme fallbacks from most places
Using dlopen to get symbols has the nice benefit that rustc itself doesn't depend on libenzyme symbols anymore. We can therefore delete most fallback implementations in the backend (independently of whether we enable enzyme or not). When trying to use autodiff on nightly, we will now fail with a nice error if and only if we fail to load libEnzyme-21.so in our backend.
Verified:
Build as nightly, without Enzyme
Build as nightly, with Enzyme
Build as stable (without Enzyme)
With this PR we will now run `tests/ui/autodiff` on nightly, the tests are passing.
r? `@kobzol`
Move shared offload globals and define per-kernel globals once
This PR moves the shared LLVM global variables logic out of the `offload` intrinsic codegen and generates kernel-specific variables only ont he first call of the intrinsic.
r? `@ZuseZ4`
tracking:
- https://github.com/rust-lang/rust/issues/131513
This commit refactors `SourceMap` and most importantly `RealFileName` to
make it self-contained in order to achieve cross-compiler consistency.
This is achieved:
- by making `RealFileName` immutable
- by only having `SourceMap::to_real_filename` create `RealFileName`
- by also making `RealFileName` holds it's working directory,
it's embeddable name and the remapped scopes
- by making most `FileName` and `RealFileName` methods take a scope as
an argument
In order for `SourceMap::to_real_filename` to know which scopes to apply
`FilePathMapping` now takes the current remapping scopes to apply, which
makes `FileNameDisplayPreference` and company useless and are removed.
The scopes type `RemapPathScopeComponents` was moved from
`rustc_session::config` to `rustc_span`.
The previous system for scoping the local/remapped filenames
`RemapFileNameExt::for_scope` is no longer useful as it's replaced by
methods on `FileName` and `RealFileName`.
automate gpu offloading - part 1
Automates step 1 from the rustc-dev-guide offload section:
https://rustc-dev-guide.rust-lang.org/offload/usage.html#compile-instructions
`"clang-offload-packager" "-o" "host.out" "--image=file=device.bc,triple=amdgcn-amd-amdhsa,arch=gfx90a,kind=openmp"`
Verified on an MI 250X
cc `@jhuber6,` `@kevinsala,` `@jdoerfert,` `@Sa4dUs`
r? oli-obk
Jonathan Brouwer