Previously, when inserting the entry function, we only checked for
duplicate _definitions_ of `main`. However, it's possible to cause
problems even only having a duplicate _declaration_. For example,
shadowing `main` using an extern block isn't caught by the current
check, and causes an assertion failure down the line in in LLVM code.
Compile some CGUs in parallel at the start of codegen
This brings the compilation time for `syntex_syntax` from 11.542s to 10.453s with 6 threads in non-incremental debug mode. Just compiling `n` CGUs in parallel at the beginning of codegen seems sufficient to get rid of the staircase effect, at least for `syntex_syntax`.
Based on https://github.com/rust-lang/rust/pull/67777.
r? @michaelwoerister
cc @alexcrichton @Mark-Simulacrum
build-std compatible sanitizer support
### Motivation
When using `-Z sanitizer=*` feature it is essential that both user code and
standard library is instrumented. Otherwise the utility of sanitizer will be
limited, or its use will be impractical like in the case of memory sanitizer.
The recently introduced cargo feature build-std makes it possible to rebuild
standard library with arbitrary rustc flags. Unfortunately, those changes alone
do not make it easy to rebuild standard library with sanitizers, since runtimes
are dependencies of std that have to be build in specific environment,
generally not available outside rustbuild process. Additionally rebuilding them
requires presence of llvm-config and compiler-rt sources.
The goal of changes proposed here is to make it possible to avoid rebuilding
sanitizer runtimes when rebuilding the std, thus making it possible to
instrument standard library for use with sanitizer with simple, although
verbose command:
```
env CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUSTFLAGS=-Zsanitizer=thread cargo test -Zbuild-std --target x86_64-unknown-linux-gnu
```
### Implementation
* Sanitizer runtimes are no long packed into crates. Instead, libraries build
from compiler-rt are used as is, after renaming them into `librusc_rt.*`.
* rustc obtains runtimes from target libdir for default sysroot, so that
they are not required in custom build sysroots created with build-std.
* The runtimes are only linked-in into executables to address issue #64629.
(in previous design it was hard to avoid linking runtimes into static
libraries produced by rustc as demonstrated by sanitizer-staticlib-link
test, which still passes despite changes made in #64780).
cc @kennytm, @japaric, @firstyear, @choller
rustc: split FnAbi's into definitions/direct calls ("of_instance") and indirect calls ("of_fn_ptr").
After this PR:
* `InstanceDef::Virtual` is only used for "direct" virtual calls, and shims around those calls use `InstanceDef::ReifyShim` (i.e. for `<dyn Trait as Trait>::f as fn(_)`)
* this could easily be done for intrinsics as well, to allow their reification, but I didn't do it
* `FnAbi::of_instance` is **always** used for declaring/defining an `fn`, and for direct calls to an `fn`
* this is great for e.g. https://github.com/rust-lang/rust/pull/65881 (`#[track_caller]`), which can introduce the "caller location" argument into "codegen signatures" by only changing `FnAbi::of_instance`, after this PR
* `FnAbi::of_fn_ptr` is used primarily for indirect calls, i.e. to `fn` pointers
* *not* virtual calls (which use `FnAbi::of_instance` with `InstanceDef::Virtual`)
* there's also a couple uses where the `rustc_codegen_llvm` needs to declare (i.e. FFI-import) an LLVM function that has no Rust declaration available at all
* at least one of them could probably be a "weak lang item" instead
As there are many steps, this PR is best reviewed commit by commit - some of which arguably should be in their own PRs, I may have gotten carried away a bit.
cc @nagisa @rkruppe @oli-obk @anp
Before this commit, we had an event that would only track the compression step
for proc-macros and Rust dylibs. After the commit we measure the time for
acutally generating the crate metadata bytes.
Remove `InternedString`
This PR removes `InternedString` by converting all occurrences to `Symbol`. There are a handful of places that need to use the symbol chars instead of the symbol index, e.g. for stable sorting; local conversions `LocalInternedString` is used in those places.
r? @eddyb
Add a target setting to allow targets to specify whether the generated
`main` function should be passed `argc` and `argv` arguments. Set it
to false on wasm32-wasi, since WASI's `args::args()` calls into the
WASI APIs itself. This will allow the WASI toolchain to avoid linking
and running command-line argument initialization code when the arguments
aren't actually needed.
SelfProfiler API refactoring and part one of event review
This PR refactors the `SelfProfiler` a little bit so that most profiling methods are RAII-based. The codegen backend code already had something similar, this refactoring pulls this functionality up into `SelfProfiler` itself, for general use.
The second commit of this PR is a review and update of the existing events we are already recording. Names have been made more consistent. CGU names have been removed from event names. They will be added back in when function parameter recording is implemented.
There is still some work to be done for adding new events, especially around trait resolution and the incremental system.
r? @wesleywiser
Remove tx_to_llvm_workers from TyCtxt
This can be kept within the codegen backend crates entirely -- there's no reason for us to create it outside and attempt to hold it in the (global) context.
Changes here aren't really too easily reviewable I suspect -- not sure if they can be cleaned up by splitting into more commits though, it's just hard to reason about `Box<Any>` in general. If there are thoughts though I'd be happy to hear them.
The primary goal of this PR is to get rid of the field on `rustc_interface::Queries`.
This commit converts a field of `Session`, `dependency_formats`, into a
query of `TyCtxt`. This information then also needed to be threaded
through to other remaining portions of the linker, but it's relatively
straightforward. The only change here is that instead of
`HashMap<CrateType, T>` the data structure changed to `Vec<(CrateType,
T)>` to make it easier to deal with in queries.
The old struct tail functions did not deal with `<T as Trait>::A` and `impl
Trait`, at least not explicitly. (We didn't notice this bug before because it
is only exposed when the tail (post deep normalization) is not `Sized`, so it
was a rare case to deal with.)
For post type-checking (i.e. during codegen), there is now
`struct_tail_erasing_lifetimes` and `struct_lockstep_tails_erasing_lifetimes`,
which each take an additional `ParamEnv` argument to drive normalization.
For pre type-checking cases where normalization is not needed, there is
`struct_tail_without_normalization`. (Currently, the only instance of this is
`Expectation::rvalue_hint`.)
All of these new entrypoints work by calling out to common helper routines.
The helpers are parameterized over a closure that handles the normalization.
Mazdak Farrokhzad