Validate constants during `const_eval_raw`
This PR implements the groundwork for https://github.com/rust-lang/rust/issues/72396
* constants are now validated during `const_eval_raw`
* to prevent cycle errors, we do not validate references to statics anymore beyond the fact that they are not dangling
* the `const_eval` query ICEs if used on `static` items
* as a side effect promoteds are now evaluated to `ConstValue::Scalar` again (since they are just a reference to the actual promoted allocation in most cases).
Some promotion cleanup
Based on top of both https://github.com/rust-lang/rust/pull/75502 and https://github.com/rust-lang/rust/pull/75585, this does some cleanup of the promotion code. The last 2 commits are new.
* Remove the remaining cases where `const fn` is treated different from `fn`. This means no longer promoting ptr-to-int casts, raw ptr operations, and union field accesses in `const fn` -- or anywhere, for that matter. These are all unstable in const-context so this should not break any stable code. Fixes https://github.com/rust-lang/rust/issues/75586.
* ~~Promote references to statics even outside statics (i.e., in functions) for consistency.~~
* Promote `&mut []` everywhere, not just in non-`const` functions, for consistency.
* Explain why we do not promote deref's of statics outside statics. ~~(This is the only remaining direct user of `const_kind`.)~~
This can only land once the other two PRs land; I am mostly putting this up already because I couldn't wait ;) and to get some feedback from `@rust-lang/wg-const-eval` .
shim: monomorphic `FnPtrShim`s during construction
Fixes#69925.
This PR adjusts MIR shim construction so that substitutions are applied to function pointer shims during construction, rather than during codegen (as determined by `substs_for_mir_body`).
r? `@eddyb`
Implement a generic Destination Propagation optimization on MIR
This takes the work that was originally started by `@eddyb` in https://github.com/rust-lang/rust/pull/47954, and then explored by me in https://github.com/rust-lang/rust/pull/71003, and implements it in a general (ie. not limited to acyclic CFGs) and dataflow-driven way (so that no additional infrastructure in rustc is needed).
The pass is configured to run at `mir-opt-level=2` and higher only. To enable it by default, some followup work on it is still needed:
* Performance needs to be evaluated. I did some light optimization work and tested against `tuple-stress`, which caused trouble in my last attempt, but didn't go much in depth here.
* We can also enable the pass only at `opt-level=2` and higher, if it is too slow to run in debug mode, but fine when optimizations run anyways.
* Debuginfo needs to be fixed after locals are merged. I did not look into what is required for this.
* Live ranges of locals (aka `StorageLive` and `StorageDead`) are currently deleted. We either need to decide that this is fine, or if not, merge the variable's live ranges (or remove these statements entirely – https://github.com/rust-lang/rust/issues/68622).
Some benchmarks of the pass were done in https://github.com/rust-lang/rust/pull/72635.
give *even better* suggestion when matching a const range
notice that the err already has "constant defined here"
so this is now *exceedingly clear*
extension to #76222
r? @estebank
do not inline black_box when building for Miri
We cannot do the assembly trick in Miri, but let's at least make sure MIR inlining does not circumvent the black_box.
Also use black_box instead of local optimization barriers in a few const tests.
Add test for checking duplicated branch or-patterns
This adds a regression test for checking `or-patterns` in MIR as shown in #75439.
This doesn't introduce a fix as I'm not sure where it would go(I suspect maybe here: src/librustc_mir_build/build/matches/mod.rs), and I'm not particularly able to fix it.
cc: @lzutao
As a side effect, we now represent most promoteds as `ConstValue::Scalar` again. This is useful because all implict promoteds are just references anyway and most explicit promoteds are numeric arguments to `asm!` or SIMD instructions.
Distribute rustc sources as part of `rustc-dev`
They can be used to provide IDE features when working on rustc plugins/backends/etc without having to locate a separate Rust checkout.
r? `@Mark-Simulacrum`
Add host triples to target lists
This PR is primarily intended to fix https://github.com/rust-lang/rustup/issues/2494, which is the second commit. That bug was introduced by #76415, and incompletely fixed by #76639. (#76639 added host triples, which gave us compilers, but missed that we also need documentation and other target-only things). However, it also removes duplicate macOS CI builders.
r? `@pietroalbini`
compare generic constants using `AbstractConst`s
This is a MVP of rust-lang/compiler-team#340. The changes in this PR should only be relevant if `feature(const_evaluatable_checked)` is enabled.
~~currently based on top of #76559, so blocked on that.~~
r? `@oli-obk` cc `@varkor` `@eddyb`
Issue 72408 nested closures exponential
This fixes#72408.
Nested closures were resulting in exponential compilation time.
This PR is enhancing asymptotic complexity, but also increasing the constant, so I would love to see perf run results.
[mir-opt] Disable the `ConsideredEqual` logic in SimplifyBranchSame opt
The logic is currently broken and we need to disable it to fix a beta
regression (see #76803)
r? `@oli-obk`
Mostly to fix ui/issues/issue-37311-type-length-limit/issue-37311.rs.
Most parts of the compiler can handle deeply nested types with a lot
of duplicates just fine, but some parts still attempt to naively
traverse type tree.
Before such problems were caught by type length limit check,
but now these places will have to be changed to handle
duplicated types gracefully.
This fixes#72408.
Nested closures were resulting in exponential compilation time.
As a performance optimization this change introduces MiniSet,
which is a simple small storage optimized set.
