rust/compiler/rustc_mir_transform/src/pass_manager.rs, branch automation/bors/try

Introduce `MirDumper` and `MirWriter`.

2025-08-31T23:19:03+00:00

MIR dumping is a mess. There are lots of functions and entry points, e.g. `dump_mir`, `dump_mir_with_options`, `dump_polonius_mir`, `dump_mir_to_writer`. Also, it's crucial that `create_dump_file` is never called without `dump_enabled` first being checked, but there is no mechanism for ensuring this and it's hard to tell if it is satisfied on all paths. (`dump_enabled` is checked twice on some paths, however!) This commit introduces `MirWriter`, which controls the MIR writing, and encapsulates the `extra_data` closure and `options`. Two existing functions are now methods of this type. It sets reasonable defaults, allowing the removal of many `|_, _| Ok(())` closures. The commit also introduces `MirDumper`, which is layered on top of `MirWriter`, and which manages the creation of the dump files, encapsulating pass names, disambiguators, etc. Four existing functions are now methods of this type. - `MirDumper::new` will only succeed if dumps are enabled, and will return `None` otherwise, which makes it impossible to dump when you shouldn't. - It also sets reasonable defaults for various things like disambiguators, which means you no longer need to specify them in many cases. When they do need to be specified, it's now done via setter methods. - It avoids some repetition. E.g. `dump_nll_mir` previously specifed the pass name `"nll"` four times and the disambiguator `&0` three times; now it specifies them just once, to put them in the `MirDumper`. - For Polonius, the `extra_data` closure can now be specified earlier, which avoids having to pass some arguments through some functions.

Use trait object references for closures.

2025-08-31T22:52:34+00:00

The dynamic dispatch cost doesn't matter for MIR dumping, which is perf-insensitive. And it's necessary for the next commit, which will store some `extra_data` closures in a struct.

Inline and remove `dump_mir_for_pass`.

2025-08-31T22:52:33+00:00

The code is more readable without it.

Print regions in `type_name`.

2025-08-14T11:13:06+00:00

Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes #145168.

Disable non-required MIR opts with `optimize(none)`

2025-01-23T17:40:41+00:00

Co-authored-by: Waffle Lapkin

mir_transform: implement forced inlining

2025-01-10T18:37:54+00:00

Adds `#[rustc_force_inline]` which is similar to always inlining but reports an error if the inlining was not possible, and which always attempts to inline annotated items, regardless of optimisation levels. It can only be applied to free functions to guarantee that the MIR inliner will be able to resolve calls.

mir validator: don't store mir phase

2024-12-02T12:38:18+00:00

Rename `PASS_NAMES` to disambiguate

2024-11-12T13:28:05+00:00

Store known passes as an IndexSet

2024-11-12T13:28:05+00:00

Validate and test `-Zmir-enable-passes`

2024-11-12T13:28:05+00:00