bors [Fri, 14 May 2021 12:58:58 +0000 (12:58 +0000)]
Auto merge of #83640 - bjorn3:shared_metadata_reader, r=nagisa
Use the object crate for metadata reading
This allows sharing the metadata reader between cg_llvm, cg_clif and other codegen backends.
This is not currently useful for rlib reading with cg_spirv ([rust-gpu](https://github.com/EmbarkStudios/rust-gpu/)) as it uses tar rather than ar as .rlib format, but it is useful for dylib reading required for loading proc macros. (cc `@eddyb)`
The object crate is already trusted as dependency of libstd through backtrace. As far as I know it supports reading all object file formats used by targets for which we support rust dylibs with crate metadata, but I am not certain. If this happens to not be the case, I could keep using LLVM for reading dylib metadata.
Marked as WIP for a perf run and as it is based on #83637.
bors [Wed, 12 May 2021 11:05:56 +0000 (11:05 +0000)]
Auto merge of #83813 - cbeuw:remap-std, r=michaelwoerister
Fix `--remap-path-prefix` not correctly remapping `rust-src` component paths and unify handling of path mapping with virtualized paths
This PR fixes #73167 ("Binaries end up containing path to the rust-src component despite `--remap-path-prefix`") by preventing real local filesystem paths from reaching compilation output if the path is supposed to be remapped.
`RealFileName::Named` introduced in #72767 is now renamed as `LocalPath`, because this variant wraps a (most likely) valid local filesystem path.
`RealFileName::Devirtualized` is renamed as `Remapped` to be used for remapped path from a real path via `--remap-path-prefix` argument, as well as real path inferred from a virtualized (during compiler bootstrapping) `/rustc/...` path. The `local_path` field is now an `Option<PathBuf>`, as it will be set to `None` before serialisation, so it never reaches any build output. Attempting to serialise a non-`None` `local_path` will cause an assertion faliure.
When a path is remapped, a `RealFileName::Remapped` variant is created. The original path is preserved in `local_path` field and the remapped path is saved in `virtual_name` field. Previously, the `local_path` is directly modified which goes against its purpose of "suitable for reading from the file system on the local host".
`rustc_span::SourceFile`'s fields `unmapped_path` (introduced by #44940) and `name_was_remapped` (introduced by #41508 when `--remap-path-prefix` feature originally added) are removed, as these two pieces of information can be inferred from the `name` field: if it's anything other than a `FileName::Real(_)`, or if it is a `FileName::Real(RealFileName::LocalPath(_))`, then clearly `name_was_remapped` would've been false and `unmapped_path` would've been `None`. If it is a `FileName::Real(RealFileName::Remapped{local_path, virtual_name})`, then `name_was_remapped` would've been true and `unmapped_path` would've been `Some(local_path)`.
cc `@eddyb` who implemented `/rustc/...` path devirtualisation
Luqman Aden [Thu, 25 Mar 2021 04:45:09 +0000 (21:45 -0700)]
Implement RFC 2951: Native link modifiers
This commit implements both the native linking modifiers infrastructure
as well as an initial attempt at the individual modifiers from the RFC.
It also introduces a feature flag for the general syntax along with
individual feature flags for each modifier.
Jubilee Young [Wed, 14 Apr 2021 22:07:36 +0000 (15:07 -0700)]
Add more SIMD math.h intrinsics
LLVM supports many functions from math.h in its IR. Many of these have
single-instruction variants on various platforms. So, let's add them so
std::arch can use them.
Yes, exact comparison is intentional: rounding must always return a
valid integer-equal value, except for inf/NAN.
bjorn3 [Wed, 31 Mar 2021 09:39:03 +0000 (11:39 +0200)]
Build with `-Cpanic=unwind` by default
This doesn't enable unwinding as cg_clif doesn't support it yet. It does
allow for linking to a cg_llvm compiled libstd.so, which uses
`-Cpanic=unwind`.