Matthias Krüger 05748c66a0 Rollup merge of #107271 - Zeegomo:drop-rmw, r=oli-obk ... Treat Drop as a rmw operation Previously, a Drop terminator was considered a move in MIR. This commit changes the behavior to only treat Drop as a mutable access to the dropped place. In order for this change to be correct, we need to guarantee that 1. A dropped value won't be used again 2. Places that appear in a drop won't be used again before a subsequent initialization. We can ensure this to be correct at MIR construction because Drop will only be emitted when a variable goes out of scope, thus having: * (1) as there is no way of reaching the old value. drop-elaboration will also remove any uninitialized drop. * (2) as the place can't be named following the end of the scope. However, the initialization status, previously tracked by moves, should also be tied to the execution of a Drop, hence the additional logic in the dataflow analyses. From discussion in [this thread](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/.60DROP.60.20to.20.60DROP_IF.60.20compiler-team.23558), originating from https://github.com/rust-lang/compiler-team/issues/558. See also https://github.com/rust-lang/rust/pull/104488#discussion_r1085556010		2023-02-08 18:32:41 +01:00
..
src	Rollup merge of #107271 - Zeegomo:drop-rmw, r=oli-obk	2023-02-08 18:32:41 +01:00
Cargo.toml	remove unused imports	2023-02-06 17:40:18 +03:00