rust/tests/mir-opt/slice_drop_shim.rs

// compile-flags: -Zmir-opt-level=0


// EMIT_MIR core.ptr-drop_in_place.[String].AddMovesForPackedDrops.before.mir
fn main() {
    let _fn = std::ptr::drop_in_place::<[String]> as unsafe fn(_);
}
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular). 2019-10-17 10:46:51 +00:00			`// compile-flags: -Zmir-opt-level=0`

Remove unnecessary `EMIT_MIR_FOR_EACH_BITWIDTH 2022-09-05 05:35:47 +00:00
pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. 2020-09-02 07:40:56 +00:00			`// EMIT_MIR core.ptr-drop_in_place.[String].AddMovesForPackedDrops.before.mir`
Add test for slice drop shims 2019-03-30 17:18:54 +00:00			`fn main() {`
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular). 2019-10-17 10:46:51 +00:00			`let _fn = std::ptr::drop_in_place::<[String]> as unsafe fn(_);`
Add test for slice drop shims 2019-03-30 17:18:54 +00:00			`}`