rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Recognize discriminant reads as no-ops in RemoveNoopLandingPads

Browse Source 
The cleanup blocks often contain read of discriminants. Teach
RemoveNoopLandingPads to recognize them as no-ops to remove
additional no-op landing pads.
This commit is contained in:
Tomasz Miąsko
2020-10-10 00:00:00 +00:00
parent 0e022fc2b8
commit ecd7862dfb
1 changed files with 1 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
compiler/rustc_mir/src/transform/remove_noop_landing_pads.rs
View File

@@ -43,7 +43,7 @@ impl RemoveNoopLandingPads {
// These are all nops in a landing pad // These are all nops in a landing pad
} }
StatementKind::Assign(box (place, Rvalue::Use(_))) => { StatementKind::Assign(box (place, Rvalue::Use(_) | Rvalue::Discriminant(_))) => {
if place.as_local().is_some() { if place.as_local().is_some() {
// Writing to a local (e.g., a drop flag) does not // Writing to a local (e.g., a drop flag) does not
// turn a landing pad to a non-nop // turn a landing pad to a non-nop